Amusement lift with HDPE curved slide

Abstract

The utility model relates to technical field of combination amusement facilities, concretely relates to a recreation elevator with HDPE curved slide, specifically includes curved slide and short distance vertical lift small two -layer elevator, and the elevator two -layer building export is butt jointed with curved slide entrance, the curved slide export is at elevator one -layer entrance close -range, wherein, the curved slide material for curved way is HDPE material, and the slide base and support adopt stainless steel material, and the slide way is assembled through the buckle and stainless steel frame, and the curved slide entrance is provided with stainless steel guardrail, the elevator adopts the scissor -type lifting platform to realize the rise and fall, utilizes the screw rod mechanical self -locking characteristic and brakes, uses alternating -current electric push -pull rod as the main drive, uses direct -current electric push rod power -assisted drive, and the scissor -type lifting platform rising process mechanical dead zone is assisted to overcome, the utility model discloses a vertical lift elevator and the slide are combined in an organic whole through the improved vertical lift elevator, and the vertical lift elevator is used to ascend to the high place, and the children's physical strength is saved.

Description

Technical Field

[0001] This utility model relates to the field of combined amusement facilities technology, specifically to an amusement elevator equipped with an HDPE curved slide and its collaborative control. Background Technology

[0002] Amusement park elevators and slides are two common facilities in children's playgrounds, fostering children's interest and curiosity. Traditional children's slides require children to climb to a high place and then slide down to the ground. This is extremely unsuitable for young children with insufficient physical strength. Traditional vertical elevators use a traction sheave system, which is relatively complex to manufacture and control, and also has a high cost. They are suitable for high-rise buildings and super-large amusement facilities. Utility Model Content

[0003] The purpose of this invention is to integrate a short-distance vertical lift small two-story elevator with a curved slide into one unit. By combining the vertical lift elevator and the slide into one unit, the vertical lift elevator can be used to reach a high place, saving children's energy. During the children's entertainment process, they can enjoy both the new experience of riding an elevator and the fun of playing on a slide.

[0004] To achieve the above objectives, this utility model provides an amusement elevator equipped with an HDPE curved slide, comprising a curved slide and a short-distance vertical lifting small two-story elevator, with the elevator's second-floor exit connected to the curved slide's entrance; the curved slide's exit is located near the elevator's first-floor entrance.

[0005] The curved slide is made of HDPE material, the slide base and support are made of stainless steel, the slide is assembled with the stainless steel frame by buckles, and a stainless steel guardrail is installed at the entrance of the curved slide.

[0006] The elevator uses a scissor lift platform to achieve ascent and descent, and utilizes the self-locking characteristic of the lead screw for braking.

[0007] Parallel tracks are arranged on both sides of the elevator shaft door opening to allow the elevator door to move up and down along the tracks.

[0008] The elevator's power system employs multiple electric push-pull rods, including AC electric push-pull rods and a pair of symmetrically distributed DC electric push rods. The AC electric push-pull rods are the main drive, driving the scissor lift platform to rise and fall. The pair of symmetrically distributed DC electric push rods on both sides of the open elevator car are the auxiliary drive, assisting in overcoming the mechanical dead zone during the ascent of the scissor lift platform.

[0009] The elevator's drive control system is based on a collaborative mechanism between AC electric push-pull rods and DC electric push-pull rods, constructing a cooperative control system based on spring energy storage adaptive adjustment.

[0010] The vertical elevator uses an open elevator car and vertically sliding elevator doors, which simplifies the design and control of the door system.

[0011] The vertical elevator employs a structure combining a scissor lift platform and an AC electric push-pull rod. The horizontal extension and retraction of the push-pull rod drives the vertical lifting of the scissor lift platform, while braking is achieved through the self-locking characteristic of the lead screw. The advantage of this structure is a smooth and comfortable ascent, eliminating the need for numerous complex starting and braking components. The disadvantage is the existence of a "mechanical dead zone" under horizontal thrust.

[0012] The follower of the scissor lift platform and the lead screw and slider of the AC electric push-pull rod are integrated and slide with the rotation of the lead screw.

[0013] The open-type elevator car has symmetrically arranged compressed gas springs of the same specification and model on both sides as buffer and energy storage components, and three-section DC electric push-pull rods of the same specification and model are arranged below them. The ends of the three-section DC electric push-pull rods are mechanically connected to the ends of the compressed gas springs.

[0014] The three-section DC electric push-pull rod serves as both a power component and an energy conversion device. As a power component, it propels the scissor lift along with the AC / DC electric push rod, helping to overcome the mechanical dead zone during the scissor lift's ascent. As an energy conversion device, it converts electrical energy into kinetic energy, and then converts the kinetic energy into elastic potential energy, which is stored within a compressed gas spring.

[0015] The cylinder of the compressed air spring is equipped with a piezoresistive sensor. A differential pressure detection circuit is constructed by using the piezoresistive sensor built into the cylinder of the compressed air spring and a piezoresistive sensor that senses the external atmospheric pressure.

[0016] The vertical elevator features an open-type elevator car with a footboard mounted on its floor. Four piezoresistive sensors are placed at the four corners of the footboard where they contact the floor. A load detection circuit is constructed using these piezoresistive sensors to sense the load-bearing capacity of the open-type elevator car's floor.

[0017] Among them, the DC electric push-pull rod adopts a direct control method, while the AC electric push-pull rod adopts an indirect control method;

[0018] The DC drive motor for the DC electric linear actuator is a brushless DC motor, directly controlled by PWM speed regulation; the AC drive motor for the AC electric linear actuator is indirectly controlled by a VFD-MH300 frequency converter.

[0019] The differential pressure detection circuit and the load detection circuit are the core sensing components of the drive control system, forming a collaborative control system. Based on spring energy storage adaptive collaborative adjustment, the following control scenarios are implemented:

[0020] The operation and control of the AC motor inside the AC electric linear actuator is extremely complex and must be controlled by a dedicated frequency converter; because the potential energy of the compressed air spring must be continuously replenished during operation, the DC electric linear actuator repeatedly starts and stops; the above factors cause the coordinated control to change with the control scenario.

[0021] Scenario 1: Real-time sensing of operating status during operation requires sensing pressure through the differential pressure detection circuit of the compressed air spring and the load detection circuit of the pedal.

[0022] Scenario 2: As the air pressure of the compressed air spring increases, the compressed air spring generates thrust to counteract various resistances during the upward movement; when the thrust reaches its peak or exceeds the resistance, the control component senses the air pressure difference through the differential pressure detection circuit and starts the AC electric push-pull rod in a timely manner.

[0023] Scenario 3: When the differential pressure rises to the upper limit, the DC drive motor of the DC electric push-pull rod will be stalled. Set the PWM duty cycle to zero in time to make the current approach zero and prevent the drive circuit from burning out. After power is cut off, the upward thrust will remain at the current value due to the elasticity of the spring.

[0024] Scenario 4: As the air pressure of the compressed air spring decreases, when the pressure difference is equal to or lower than the equilibrium point, i.e. the elastic thrust is equal to or close to the upward resistance, the DC drive motor of the DC electric push-pull rod is promptly started with PWM soft start.

[0025] This invention provides a playground elevator equipped with an HDPE curved slide, specifically comprising a curved slide and a short-distance vertical lift small two-story elevator. The elevator's second-floor exit connects to the curved slide's entrance; the curved slide's exit is located near the elevator's first-floor entrance. The curved slide's curve is made of HDPE, while the slide base and supports are made of stainless steel. The slide is assembled with a stainless steel frame using snap-fit ​​mechanisms, and a stainless steel guardrail is installed at the curved slide's entrance. The elevator uses a scissor lift platform for ascent and descent, utilizing the self-locking characteristic of a screw mechanism for braking. It employs an AC electric push-pull rod as the primary drive and a DC electric push rod for auxiliary drive, helping to overcome the mechanical dead zone during the scissor lift platform's ascent. This invention combines an improved vertical lift elevator and slide into one unit, allowing children to reach higher places with the help of the vertical lift elevator, saving their energy. Attached Figure Description

[0026] This utility model relates to the field of combined entertainment facilities technology, to composite drive technology combining and coordinating DC drive systems and AC drive systems, and to collaborative control technology based on intelligent sensing spring energy storage adaptive adjustment.

[0027] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a schematic diagram of the overall structure of an amusement elevator equipped with an HDPE curved slide, according to a specific embodiment of this utility model.

[0029] Figure 2 This is a front view of the elevator section in a specific embodiment of this utility model.

[0030] Figure 3 This is a top view of the elevator section in a specific embodiment of this utility model.

[0031] Figure 4 This is a schematic diagram showing the distribution of the power components of the elevator section on the substrate in a specific embodiment of this utility model.

[0032] Figure 5 This is a schematic diagram showing the integrated structure of the slider of the AC electric push-pull rod and the follower of the scissor lift platform in a specific embodiment of this utility model.

[0033] Figure 6 for Figure 3 A schematic diagram showing the location of the cutting line.

[0034] Figure 7 for Figure 6 A schematic diagram of the structure of section A.

[0035] Figure 8 for Figure 6 A schematic diagram of the structure of section B.

[0036] Figure 9 This is a schematic diagram of the power entity model of the lifting system powered by a three-section DC electric push-pull rod in a specific embodiment of this utility model.

[0037] Figure 10 This is a schematic diagram of a test model for measuring the running time of a lifting system powered by a three-section DC electric push-pull rod, as described in a specific embodiment of this utility model.

[0038] Figure 11 This is a schematic diagram of an ideal operating model of the elevator's upward stroke in a specific embodiment of this utility model (excluding the AC electric push-pull rod).

[0039] Figure 12This is a schematic diagram of an ideal operating model of the elevator's descent stroke in a specific embodiment of this utility model (excluding the AC electric push-pull rod).

[0040] Figure 13 This is a schematic circuit diagram illustrating the principle of PWM control for a brushless DC motor in a specific embodiment of this utility model.

[0041] Figure 14 This is a schematic diagram of a half-bridge circuit constructed using the EG2104 chip in a specific embodiment of this utility model. The low-level signal is a control signal.

[0042] Figure 15 This is a schematic diagram of a half-bridge circuit constructed using the EG2104 chip in a specific embodiment of this utility model. The high-level signal is a control signal.

[0043] Figure 16 The diagram below shows the actual circuit constructed using two EG2104 chips in a specific embodiment of this utility model, employing a full-bridge circuit.

[0044] Figure 17 This is a schematic diagram of the wiring between the microcontroller's I / O port and the DC motor control circuit of a pair of DC electric push-pull rods in a specific embodiment of this utility model.

[0045] Figure 18 This is a schematic diagram of an ideal operating model of the elevator's upward stroke in a specific embodiment of this utility model (including AC electric push-pull rod).

[0046] Figure 19 This is a schematic diagram of an ideal operating model of the elevator's descent stroke in a specific embodiment of this utility model (excluding the AC electric push-pull rod).

[0047] Figure 20 This is a schematic diagram of a frequency converter drive servo system for driving an AC motor in a specific embodiment of this utility model.

[0048] Figure 21 for Figure 2 Diagram showing the location of the cutting line.

[0049] Figure 22 for Figure 21 The diagram shows the C-section structure, where: Top-level button group: Button A - Descend request button, B - Open door request button, C - Call elevator request button, D - Close door request; Top-level button group: Button A - Ascend request button, B - Open door request button, C - Call elevator request button, D - Close door request.

[0050] Figure 23 This is a three-dimensional structural diagram of an open elevator car in a specific embodiment of this utility model.

[0051] Figure 24The following are three views of the pedal in a specific embodiment of this utility model.

[0052] Figure 25 This is a partial cross-sectional structural diagram of the mechanical connection between the pedal, the floor of the open elevator car, and the surface of the scissor lift platform in a specific embodiment of this utility model.

[0053] Figure 26 This is a simplified schematic diagram of a scissor lift in a specific embodiment of this utility model.

[0054] Figure 27 These are two views of the compressed air spring in a specific embodiment of this utility model, namely the front view, the top view, and the cross-sectional view of section D.

[0055] Figure 28 This is a schematic diagram of the structure of the end of the three-section DC electric push-pull rod in a specific embodiment of this utility model.

[0056] Figure 29 This is a partial cross-sectional view of the mechanical connection between the ends of the three electric push-pull rods and the compressed gas spring in a specific embodiment of this utility model.

[0057] Figure 30 This is a characteristic curve of the compressed gas spring in a specific embodiment of this utility model.

[0058] Figure 31 This is a schematic diagram of the circuit system with the No. 1 microcontroller as the core in a specific embodiment of this utility model.

[0059] Figure 32 This is a schematic diagram of the #2 microcontroller collaborative status register in a specific embodiment of this utility model.

[0060] Figure 33 This is a schematic diagram of the microcontroller relay control circuit structure in a specific embodiment of this utility model.

[0061] Figure 34 This is a schematic diagram of the circuit structure for controlling the AC contactor via the IO0 output port of the #1 microcontroller in a specific embodiment of this utility model.

[0062] Figure 35 This is a flowchart illustrating the subroutine for driving a DC motor in a specific embodiment of this utility model.

[0063] Figure 36 This is a schematic diagram showing the distribution of components in the single-acting guide rail cylinder control system and its surrounding area in a specific embodiment of this utility model.

[0064] Figure 37 This is a schematic diagram showing the distribution of relevant components for the single-acting cylinder intake control in a specific embodiment of this utility model.

[0065] Figure 38 This is a schematic diagram showing the distribution of relevant components for the single-acting cylinder exhaust control in a specific embodiment of this utility model.

[0066] Figure 39 This is a schematic diagram showing the connection of the main components of the intelligent detection and control core part of the elevator in a specific embodiment of this utility model.

[0067] Figure 40 This is a schematic diagram of the main program flow of the No. 2 microcontroller in a specific embodiment of this utility model.

[0068] Figure 41 This is a schematic diagram of the peripheral circuit structure of the limit switch and electromagnetic door catcher in a specific embodiment of this utility model.

[0069] Figure 42 This is a schematic diagram illustrating the initial state of the electromagnetic door release process in a specific embodiment of this utility model.

[0070] Figure 43 This is a schematic diagram illustrating the subsequent state of the electromagnetic door release process in a specific embodiment of this utility model.

[0071] Figure 44 This is a simplified structural diagram of a normally closed pilot-operated two-position three-way valve in a specific embodiment of this utility model.

[0072] Figure 45 This is a schematic diagram of the initial state of the normally closed pilot-operated two-position three-way valve control circuit under the action of the "relay delay control signal" in the intake control process of a single-acting cylinder, according to a specific embodiment of this utility model.

[0073] Figure 46 This is a schematic diagram illustrating the subsequent state of the normally closed pilot-operated two-position three-way valve control circuit under the action of the "relay delay control signal" in the intake control process of a single-acting cylinder, according to a specific embodiment of this utility model.

[0074] Figure 47 This is a schematic diagram showing the power supply circuit of the electric bolt lock in an open circuit state in a specific embodiment of this utility model.

[0075] Figure 48 This is a schematic diagram showing the power supply circuit of the electric bolt lock in a continuous state in a specific embodiment of this utility model.

[0076] Figure 49 This is a schematic diagram showing the change of the power supply circuit of the electric bolt lock from a continuous state to an open state in a specific embodiment of this utility model.

[0077] Figure 50 This is a schematic diagram of the circuit state of the elevator door opening control circuit before the preset time in a specific embodiment of this utility model.

[0078] Figure 51This is a schematic diagram of the circuit state of the elevator door opening control circuit after a preset time in a specific embodiment of this utility model.

[0079] Figure 52 This is a schematic diagram showing the interface signals of the elevator door opening and closing control hardware circuit in a specific embodiment of this utility model.

[0080] Figure 53 This is a schematic diagram of the AL2O3 ceramic copper infiltration technology in a specific embodiment of this utility model.

[0081] Figure 54 The image shows two views of the AL2O3 ceramic round cover in a specific embodiment of this utility model.

[0082] Figure 55 This is a schematic diagram of the cylinder piston structure of the compressed air spring in a specific embodiment of this utility model.

[0083] Figure 56 This is a schematic diagram of the temperature compensation circuit in a specific embodiment of the present invention.

[0084] 1-Curved slide, 2-Baseboard, 3-Underground equipment room, 4-Elevator shaft, 5-Three-section DC electric push-pull rod A, 6-Elevator shaft top cover, 7-Open elevator car, 8-Compressed gas spring A, 9-Ultrasonic ranging sensor, 10-Step, 11-Compressed gas spring B, 12-Three-section DC electric push-pull rod B, 13-Scissor lift platform, 14-Single-acting guide rail cylinder control system, 15-Glass window, 16-Button group, 17-Elevator door (up and down sliding door), 18-AC electric push-pull rod, 19-Rotary encoder. Detailed Implementation

[0085] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0086] This utility model provides an amusement elevator equipped with an HDPE curved slide, including a curved slide and a short-distance vertical lifting small two-story elevator, with the elevator's second-floor exit connected to the curved slide's entrance; the curved slide's exit is located near the elevator's first-floor entrance.

[0087] The curved slide is made of HDPE material, the slide base and support are made of stainless steel, the slide is assembled with the stainless steel frame by buckles, and a stainless steel guardrail is installed at the entrance of the curved slide.

[0088] The elevator uses a scissor lift platform to achieve ascent and descent, and utilizes the self-locking characteristic of the lead screw for braking.

[0089] The elevator uses an open elevator car and vertically sliding elevator doors, which simplifies the design and control of the door system.

[0090] The elevator's power system uses multiple electric push-pull rods, including AC electric push-pull rods and DC electric push rods; the AC electric push-pull rods are the main drive, driving the scissor lift platform to rise and fall; a pair of DC electric push rods symmetrically distributed on both sides of the open elevator car are the auxiliary drive, helping to overcome the mechanical dead zone during the ascent of the scissor lift platform.

[0091] The follower of the scissor lift platform and the slider of the AC electric push-pull rod are integrated and slide as the lead screw rotates. The slider and follower of the scissor lift platform are designed and manufactured as a single component. The two sides of this component are cylindrical and mate with the sliding grooves of the scissor lift platform, forming the follower. The central part of this component, which is essentially a slider, slides as the lead screw rotates.

[0092] The open-type elevator car is equipped with compressed gas springs on both sides as cushioning components. The spring deformation compensates for the deviation between the lifting stroke of the scissor lift platform and the extension stroke of the DC electric push rod. The cylinders of the compressed gas springs contain piezoresistive sensors to monitor changes in cylinder air pressure. The DC motor speed is controlled by adjusting the PWM duty cycle. During operation, based on changes in cylinder air pressure and the actual load, the AC motor is started and the DC motor is controlled in a timely manner, thus enabling the DC and AC electric push rods to work in tandem.

[0093] Furthermore, the tail end of the compressed gas spring in this invention is fixed using a common T-joint component. The tail end of the compressed gas spring is lengthened, making it longer than that of a typical compressed spring. The tail end is integrally designed and cast with the cylinder. The purpose of lengthening the tail end is to facilitate the fixing of the compressed gas spring to both sides of an open elevator car. With the tail end lengthened, two T-joints can be used to fix the compressed gas spring to both sides of the open elevator car.

[0094] Parallel guide rails are fixed on both sides of the elevator door. The elevator door is driven to move by a single-acting cylinder. In this utility model, the spring inside the single-acting cylinder is removed, and the pneumatic thrust of the cylinder is enhanced, but it is difficult to automatically recover. Recovery depends on the gravity of the elevator door.

[0095] In this embodiment, the inverter operates in vector control mode. The microcontroller controlling the DC electric actuator is the host computer, i.e., the control core of the collaborative system, while the microcontroller controlling the AC electric actuator is the slave computer.

[0096] An open-plan elevator car has a footboard mounted on its floor. Four piezoresistive sensors are placed at the four corners of the footboard where they contact the floor. A load detection circuit is constructed using these piezoresistive sensors to sense the load-bearing capacity of the open-plan elevator car's floor.

[0097] The function of the load detection circuit is to obtain the current load value and feed it back to the control components so that they can adjust the relevant parameter settings or issue an overload alarm; the current load value is the measured load-bearing value of the floor plate of the open elevator car.

[0098] A piezoresistive sensor is installed inside the cylinder of the compressed air spring. A differential pressure detection circuit is constructed by combining the piezoresistive sensor built into the cylinder of the compressed air spring with a piezoresistive sensor that senses the external atmospheric pressure.

[0099] The function of the differential pressure detection circuit is to obtain the difference between the compressed air spring pressure and the external atmospheric pressure and feed it back to the control components.

[0100] The differential pressure detection circuit and the load detection circuit are the core sensing components of the drive control system, forming a collaborative control system.

[0101] The operation and control of the AC motor inside the AC electric linear actuator is extremely complex and must be controlled by a dedicated frequency converter; because the potential energy of the compressed air spring must be continuously replenished during operation, the DC electric linear actuator repeatedly starts and stops; the above factors lead to different control method settings.

[0102] DC electric push-pull rods use a direct control method, while AC electric push-pull rods use an indirect control method.

[0103] The DC drive motor for the DC electric linear actuator is a brushless DC motor, directly controlled by PWM speed regulation; the AC drive motor for the AC electric linear actuator is indirectly controlled by a VFD-MH300 frequency converter.

[0104] The following control scenarios are based on spring energy storage adaptive coordinated regulation:

[0105] Scenario 1: Real-time sensing of operating status during operation requires sensing pressure through the differential pressure detection circuit of the compressed air spring and the load detection circuit of the pedal.

[0106] Scenario 2: As the air pressure of the compressed air spring increases, the compressed air spring generates thrust to counteract various resistances during the upward movement; when the thrust reaches its peak or exceeds the resistance, the control component senses the air pressure difference through the differential pressure detection circuit and starts the AC electric push-pull rod in a timely manner.

[0107] Scenario 3: When the differential pressure rises to the upper limit, the DC drive motor of the DC electric push-pull rod will be stalled. Set the PWM duty cycle to zero in time to make the current approach zero and prevent the drive circuit from burning out. After power is cut off, the upward thrust will remain at the current value due to the elasticity of the spring.

[0108] Scenario 4: As the air pressure of the compressed air spring decreases, when the pressure difference is equal to or lower than the equilibrium point, i.e. the elastic thrust is equal to or close to the upward resistance, the DC drive motor of the DC electric push-pull rod is promptly started with PWM soft start.

[0109] This invention employs a software-triggered synchronization design only for the startup time of the drive system; the overall product adopts an adaptive and cooperative design. In a real system containing multiple drive components, the coordination between the AC and DC drive components relies on the adaptability of the relevant components and the adaptive design of the related control system.

[0110] The entire elevator system comprises an inseparable electromechanical component and an intelligent detection and control component. The core of the intelligent detection and control component consists of five microcontrollers. Microcontroller #1 and #2 control the DC drive system and AC drive system respectively; microcontroller #1 is the control core of the entire drive system, and microcontroller #2 is a slave of microcontroller #1. Microcontrollers #4 and #5 are the control cores of the first-floor and second-floor elevator door systems respectively, referred to as the sub-controllers. Microcontroller #3 is the master control microcontroller, serving as the host computer for all microcontrollers and the control core of the entire system.

[0111] Please see Figures 1 to 56 The present invention will be further described below with reference to specific embodiments:

[0112] Figure 1 This is a schematic diagram of the overall composition of this utility model. A small, two-story elevator with short-distance vertical lifting and a curved slide are integrated into one unit. The elevator section adopts an axisymmetric design. The curved slide uses multiple curved paths to meet the following two conditions: the elevator's second-floor exit connects with the slide's curved entrance; and the slide's curved exit is located close to the elevator's first-floor entrance.

[0113] The curved slide is made of HDPE material, while the base and support are made of stainless steel. The slide is assembled with the stainless steel frame using clips, and a stainless steel guardrail is installed at the entrance of the curved slide.

[0114] The curved slide employs a slow-speed design to ensure the safety of young children, while increasing the length of the curve to enhance the sliding experience. As the curve length increases, the slope decreases, leading to a higher coefficient of friction. To reduce this coefficient of friction, polyethylene wax is added during the HDPE material processing. This technology reduces surface friction and improves the material's high-temperature resistance.

[0115] Figure 2 This is a front view of the elevator portion of this utility model, specifically a front view of a small two-story elevator with short-distance vertical lifting, in which the elevator is in operation.

[0116] Figure 3 This is a top view of the elevator portion of this utility model, specifically a top view of a small, two-story elevator with short-distance vertical lifting. The outer dashed frame represents the base plate 2, buried underground, upon which numerous power components are fixed. The inner dashed frame represents the underground equipment room 3, fixed to the base plate 2 and buried underground. The solid frame represents the location of the elevator shaft 4, fixed to the base plate 2 and exposed above ground.

[0117] Figure 4 This is a schematic diagram showing the distribution of power components on the base plate 2. The dashed box on the left indicates the location of the underground equipment room 3, and the dashed box on the right indicates the location of the elevator shaft 4. The three-section DC electric push-pull rod A 5 and the three-section DC electric push-pull rod B 12 are located on both sides of the scissor lift platform 13, and are distributed symmetrically along the axis.

[0118] The scissor lift platform 13 has four threaded holes on its surface for securing the open elevator car 7, which will be described later. An AC electric push-pull rod 18 operates on the scissor lift platform 13. A rotary encoder 19 is used to measure the AC motor speed of the AC electric push-pull rod 18.

[0119] Figure 5 This is a schematic diagram of the mechanical connection between the AC electric push-pull rod 18 and the scissor lift platform 13. The AC electric push-pull rod 18 consists of an AC drive motor, a lead screw, and a slider, among other accessories. A rotary encoder 19 is used to measure the speed of the AC drive motor. The AC drive motor drives the lead screw to rotate, and the lead screw drives the slider to move back and forth linearly. The scissor lift platform 13 has a pair of scissor arms, one of which is fixed to a fixed shaft, and the other is fixed to a sliding shaft, i.e., a follower. The sliding shaft, i.e., the follower, is embedded in a sliding groove. The mechanical connection between the AC electric push-pull rod 18 and the scissor lift platform 13 is shown in dashed boxes, with the slider in the middle and the followers on both sides. The ends of the followers are cylindrical, and the slider and the followers on both sides are designed as a whole. This integrated design is used to improve rigidity. When the AC drive motor rotates, the lead screw converts the rotational motion into the linear motion of the slider, which in turn drives the follower to move back and forth linearly within the sliding groove, causing the scissor lift platform 13 to rise and fall.

[0120] Figure 6 for Figure 3 A schematic diagram of the cutting line position, for Figure 1 The top view of the elevator section of the structure shown is... Figure 3 The sections were cut, and the specific locations of section A and section B were marked. Figure 1 The elevator section shown is a symmetrical structure, requiring that the symmetrically distributed components have identical parameters and specifications, and that the drive components on both sides of the axis of symmetry operate in complete synchronization. The relevant elevator structure is further clarified through section planes A and B.

[0121] Figure 7 As shown Figure 6A schematic diagram of section A is shown. In this diagram, three dashed frames are used. The component in the left dashed frame is a three-section DC electric push-pull rod A5, the component in the middle dashed frame is a scissor lift platform 13, and the component in the right dashed frame is a three-section DC electric push-pull rod B12. This schematic diagram shows the open elevator car 7 fixed together with the scissor lift platform 13. Compressed gas springs A8 and B11 are fixed to both sides of the open elevator car 7. The bases of the three-section DC electric push-pull rods A5 and B12 are fixed to the base plate 2. Compressed gas spring A8 is mechanically connected to the three-section DC electric push-pull rod A5 using a U-shaped connector. Compressed gas spring B11 is mechanically connected to the three-section DC electric push-pull rod B12 using a U-shaped connector. AC electric push-pull rod 18 (see...) Figure 4 The AC electric push-pull rod 18, the three-section DC electric push-pull rod A 5, and the three-section DC electric push-pull rod B 12 all act on the compressed gas spring B 11. The AC electric push-pull rod 18, the three-section DC electric push-pull rod A 5, and the three-section DC electric push-pull rod B 11 extend and retract simultaneously. The pedal 10 is placed on the floor of the open elevator car 7. The four pads at the bottom of the pedal 10 are piezoresistive sensors (see...). Figure 24 ), the load-bearing capacity of the floor plate of the sensor-operated open elevator car 7.

[0122] Figure 7 The three-section DC electric push-pull rods A5 and B12 shown are long-stroke DC electric push-pull rods with integrated limit switches (such as micro switches or magnetic switches). When the push-pull rod moves to a set position (usually the start or end point), the nut or stop block triggers the switch, cutting off the power to stop the motor. When the three-section DC electric push-pull rod extends or retracts to the end of its stroke, the power is automatically cut off to stop the motor. The push-pull rod uses a T-type toothed screw with a self-locking coefficient of less than or equal to 0.25, and is custom-manufactured with a relevant manufacturer to meet unidirectional self-locking requirements. This technology is existing technology, and it is one of the technical combinations adopted in this utility model design. The DC motor of the three-section DC electric push-pull rod is a brushless DC servo motor (BLDC).

[0123] Figure 8 As shown Figure 6 A schematic diagram of the structure of section B. Figure 8 The equipment shown within the dashed frame is a scissor lift platform 13. This schematic diagram illustrates the power structure of the scissor lift platform and the location of the components of the elevator doors and windows. It consists of the scissor lift platform 13, AC electric push-pull rod 18, rotary encoder 19, underground equipment room 3, elevator shaft 4, open elevator car 7, ultrasonic ranging sensor 9, pedals 10, single-acting guide rail cylinder control system 14, glass window 15, button group 16, and sliding door (elevator door) 17. The specific composition and control method of the single-acting guide rail cylinder control system 14 are described below. Figure 36 , Figure 37 and Figure 38 Detailed description. The scissor lift platform is powered by an AC electric push-pull rod 18.

[0124] Figure 8 This embodiment demonstrates the core structure of a short-distance vertical lifting mini two-story elevator. The main components of the short-distance vertical lifting mini two-story elevator are as follows: a door system controlled by a single-acting guide rail cylinder, a lifting system powered by an electric push-pull rod, and various auxiliary devices including an elevator shaft 4 and an underground equipment room 3. The elevator shaft 4 prevents the equipment from being exposed to the outside world and is equipped with a machine room opening and door / window openings. The elevator doors and windows use new heat-insulating float glass, which can block 90% of infrared light transmission; the elevator door frame is made of lightweight stainless steel. The single-acting guide rail cylinder control system 14 is mainly used to control the translation of the vertical sliding door, i.e., the elevator door 17.

[0125] Figure 8 The AC electric push-pull rod 18 and the single-acting guide rail cylinder control system 14 shown are two drive components. The specific composition and control method of the single-acting guide rail cylinder control system 14 will be discussed later. Figure 36 , Figure 37 and Figure 38 Detailed description. The scissor lift platform is powered by an AC electric push-pull rod 18. The AC electric push-pull rod 18 is composed of an AC drive motor, a lead screw, and a slider, among other parts. The slider and the follower of the scissor lift platform 13 are integrated into a single unit. The extension and retraction of the AC electric push-pull rod 18 generates thrust or pull force, causing the scissor lift platform 13 to rise or fall. A rotary encoder 19 is used to measure the speed of the AC drive motor.

[0126] Figure 8 The AC electric push-pull rod 18 shown uses a trapezoidal lead screw with an isosceles trapezoidal thread profile, a standard tooth angle of 30 degrees, and equidistant 15-degree angles on both sides. This ensures symmetrical force distribution during bidirectional transmission, resulting in more even wear. When paired with a standard nut, it provides a reliable bidirectional self-locking function. This design does not employ a braking device; braking is achieved entirely through the lead screw's self-locking function.

[0127] Figure 8The extended shaft of the asynchronous AC motor shown can be connected to the rotary encoder 19 via a coupling, or a detachable handwheel can be installed. The underground equipment room 3 is detachable, and the DC motor electrodes of the three-section DC electric push-pull rod A 5 and the three-section DC electric push-pull rod B 12 can be externally connected to a new power supply for debugging. When a fault occurs, the open-type elevator car 7 is suspended in mid-air. The motor drive power supply is turned off, the 5V power supply continues to work, and the sensor display circuit works normally. The ground is lifted, the underground equipment room 3 and the rotary encoder 19 are removed, the detachable handwheel is installed, and the shaft of the asynchronous AC motor is manually rotated to lower the open-type elevator car 7 to the ground. The operation process is as follows: the DC motor electrodes are reversed to a 24V DC power supply (this power supply is a new power supply for debugging), causing it to reverse. A resistor with a suitable resistance value is connected in series in the circuit, the compressed air spring is stretched, the differential pressure detection circuit display value is observed, and the power supply to the DC motor is stopped in time to avoid damage to the compressed air spring. The shaft of the asynchronous AC motor is manually rotated to lower the open-type elevator car 7, and the spring returns to its original state. This process is repeated until the open-type elevator car 7 descends to the ground. The above describes the convenience of maintenance provided by mounting a detachable handwheel on the extended shaft of the asynchronous AC motor. The detachable handwheel is existing technology. This existing technology is one of the technical combinations adopted in this utility model design.

[0128] Figure 9 The diagram shows a physical model of a lifting system powered by an electric push-pull rod. The purpose of establishing this model is to determine the power consumption caused by the rated load and frictional forces. The scissor lift platform 13 (powered by an AC electric push-pull rod 18), along with three-section DC electric push-pull rods A5 and B12, employ an adaptive cooperative design. All three extend and retract simultaneously, causing the open-type elevator car 7 to rise and fall. The three-section DC electric push-pull rods A5 and B12 are of the same specifications. The compressed air springs A8 and B11 are of the same specifications. The U-shaped connector at the end of the three-section DC electric push-pull rod A5 and the compressed air spring A8 (see...) Figure 29 ) is connected by mechanical parts such as bolts and nuts, in Figure 9 The dynamic solid model shown uses long bolts for mechanical connections. The end of the three-section DC electric push-pull rod B12 connects to the U-shaped joint of the compressed gas spring B11 (see...). Figure 29 ) is connected by mechanical parts such as bolts and nuts, in Figure 9 The dynamic solid model shown uses long bolts for mechanical connection. The ultrasonic ranging sensor 9 moves above the end of the long bolt, and the actual extension and retraction of the end of the three-section DC electric push-pull rod B12 is obtained by measuring the change in the position of the bolt end. By changing the weight of the load on the open elevator car 7 and measuring the extension speed of the end of the three-section DC electric push-pull rod B12, the relationship between load and extension speed is obtained. Figure 9The thick dashed line shown indicates the original position of the ultrasonic ranging sensor 9, which has now moved to the top of the end of the long bolt.

[0129] To test the full-load speed, the AC electric push-pull rod 18 should be removed, and the power should come entirely from the three-section DC electric push-pull rod A 5 and the three-section DC electric push-pull rod B 12. The full-load speed is an important parameter of the three-section DC electric push-pull rods, provided by the manufacturer. The voltage of the DC drive motor loaded on the three-section DC electric push-pull rods is the rated voltage of 24V. By continuously changing the weight of the load on the open elevator car 7, when the average upward speed of the end of the three-section DC electric push-pull rod B 12 is exactly the full-load speed provided by the manufacturer, the load on the open elevator car 7 is the rated load. The load on the open elevator car 7 in the following text refers to the rated load, which is determined by this method. During the measurement process, the power components of the same specification and model are symmetrically distributed on both sides of the scissor lift platform 13, and the upward speed of the end of the three-section DC electric push-pull rod B 12 is equal to the upward speed of the end of the three-section DC electric push-pull rod A 5.

[0130] To test power consumption, the AC electric push-pull rod 18 should be removed, and the power should come entirely from the three-section DC electric push-pull rod A 5 and the three-section DC electric push-pull rod B 12. The open-type elevator car 7 is unloaded (zero load). The DC power supply is used to measure power consumption using a power meter. The elevator is started and stopped immediately when the power meter reaches one watt. The current displacement s is obtained using an ultrasonic ranging sensor, and the motor is simultaneously reversed to begin the return journey. Once back to the starting point, the useful work done is zero. The total energy consumed is obtained as w using the power meter. The inherent friction force f is calculated using the formula w = 2fs.

[0131] Figure 10 The diagram shows a test model for measuring the running time of a lifting system powered by a three-section DC electric push-pull rod. The purpose of establishing this dynamic test model is to determine the average speed of the follower of the scissor lift platform 13. This model is structurally similar to the dynamic solid model, but its load remains constant at the rated load. To ensure the AC drive system output power is zero, the AC electric push-pull rod 18 is removed. With zero AC drive system output power, the open elevator car 7 rises and falls under the action of the DC drive system, and the follower of the scissor lift platform 13 moves at varying speeds. This model is used to test the speed of the follower of the scissor lift platform 13. An ultrasonic ranging sensor 9 is located above the open elevator car 7, monitoring the movement process and time of the elevator car 7 from the starting point to the ending point. In this model, the compressed air spring A 8 and compressed air spring B 11 cylinders are dynamically balanced under the rated load. This model measures the time of the follower of the scissor lift platform 13 from the starting point to the ending point. Since the starting and ending points are fixed, the average speed of the follower of the scissor lift platform 13 can be obtained through calculation.

[0132] An ideal model is abstracted based on the test model. In the ideal model, the follower moves at a constant speed, equal to the average speed of the follower in the test model. The ideal model removes the AC electric push-pull rod 18, while maintaining its rated load. It moves from the starting point to the ending point. The test model realistically reflects the actual test conditions; the ideal model, however, is abstracted and simplified, idealizing the actual variable-speed motion as uniform motion. The test model and the ideal model complete the same stroke within the same time. The speed of the follower's uniform motion in the ideal operating models for the upward and downward strokes, as described later, is based on the average speed of the follower measured in the test model. The purpose of establishing the ideal model is to provide initial values ​​for setting the relevant parameters of the AC drive motor.

[0133] Figure 11 The diagram illustrates an ideal operating model for the ascent of a small, two-story elevator with short-distance vertical lifting. It assumes the follower of the scissor lift platform 13 is in uniform motion. According to Newton's first law, an object in uniform motion experiences zero force or a net force. The follower is only acted upon by the AC electric push-pull rod 18; therefore, the assumption is satisfied only when the force exerted by the AC electric push-pull rod 18 is zero and its output power is zero. For clarity, the AC electric push-pull rod 18 is removed, and only the follower and its slide of the scissor lift platform 13 are partially shown. The scissor lift platform 13 itself is hidden, and components such as the three-section DC electric push-pull rod A 5 and the three-section DC electric push-pull rod B 12 are not displayed. The open-type elevator car 7 is located on the first floor, in the initial stage of its ascent, and carries its rated load. Under the combined propulsion of three-section DC electric push-pull rod A5 and three-section DC electric push-pull rod B12, the follower of the scissor lift platform 13 moves at a constant speed from X1 to X2, and the open elevator car 7 rises from the bottom floor (coordinate Y1) to the top floor (coordinate Y2). The solid circle represents the start point of the follower, and the hollow circle represents the end point. The uniform motion state set in the ideal model is difficult to achieve in reality; in actual measurement, only the travel time from the start point to the end point can be obtained. Using... Figure 10 The test entity model of the lifting system powered by a three-section DC electric push-pull rod is shown to test the average running speed v1 of the follower of the scissor lift platform 13. Using an ultrasonic ranging device, the starting time t0 of the open elevator car 7 corresponds to the car coordinate Y1, and the time t1 corresponding to the open elevator car 7 rising to Y2 is recorded. The measured speed v1 = (X2 - X1) / (t1 - t0). Assuming v1 is... Figure 11 The ideal operating model shown has a uniform operating speed of v1, meaning the servo moves at a constant speed of v1. The theoretical result obtained is the same as the actual result, that is, the starting point reaches the ending point in the same amount of time.

[0134] Microcontroller #1 controls the start and stop of the DC motor of the DC electric push-pull rod through a DC drive control circuit, and uses PWM speed regulation technology to control its speed. Microcontroller #2 detects the longitudinal coordinate position of the open elevator car 7 through an ultrasonic ranging circuit, records the start time t0 when the open elevator car 7 is at coordinate Y1, and records the end time t1 when the open elevator car 7 is at coordinate Y2. Figure 11 The DC drive control circuit shown consists of Figure 13 , Figure 14 , Figure 15 , Figure 16 and Figure 17 Detailed description.

[0135] Figure 12 The diagram illustrates an ideal operating model for the descent of a small, two-story elevator with short-distance vertical lifting. It assumes the follower of the scissor lift platform 13 is in uniform motion. According to Newton's first law, an object in uniform motion experiences zero force or a net force. The follower is only acted upon by the AC electric push-pull rod 18; therefore, the assumption is satisfied only when the force exerted by the AC electric push-pull rod 18 is zero and its output power is zero. For clarity, the AC electric push-pull rod 18 is removed, and only the follower and its slide of the scissor lift platform 13 are partially shown. The scissor lift platform 13 itself is hidden, and components such as the three-section DC electric push-pull rod A 5 and the three-section DC electric push-pull rod B 12 are not displayed. The open-type elevator car 7 is located on the second floor, in the initial stage of its descent, and carries its rated load. When the three-section DC electric push-pull rod A5 and the three-section DC electric push-pull rod B12 retract simultaneously, the follower of the scissor lift platform 13 moves at a constant speed from X2 to X1, and the open elevator car 7 descends from the top floor (coordinate Y2) to the bottom floor (coordinate Y1). The solid circle represents the start point of the follower, and the hollow circle represents the end point. The uniform motion state set in the ideal model is difficult to achieve in reality; in actual measurements, only the travel time from the start point to the end point can be obtained. Using... Figure 10 The test entity model of the lifting system powered by a three-section DC electric push-pull rod is shown to test the average running speed v2 of the servo of the scissor lift platform 13. Using an ultrasonic ranging device, the starting time t3 of the open elevator car 7 corresponds to the car coordinate Y2, and the time t4 corresponding to the descent of the open elevator car 7 to Y1 is recorded. The measured speed v2 = (X2 - X1) / (t4 - t3). Assume v2 is... Figure 11 The ideal operating model shown has a uniform operating speed of v2, meaning the servo moves at a constant speed of v2. The theoretical result obtained is the same as the actual result, that is, the starting point reaches the ending point in the same amount of time.

[0136] Microcontroller #1 controls the start and stop of the DC motor of the DC electric push-pull rod through a DC drive control circuit, and uses PWM speed regulation technology to control its speed. Microcontroller #2 detects the longitudinal coordinate position of the open elevator car 7 through an ultrasonic ranging circuit, records the start time t3 when the open elevator car 7 is at coordinate Y2, and records the end time t4 when the open elevator car 7 is at coordinate Y1. Figure 12 The DC drive control circuit shown consists of Figure 13 , Figure 14 , Figure 15 , Figure 16 and Figure 17 Detailed description.

[0137] Figure 13 The circuit diagram shown illustrates the principle of PWM control for a DC motor, employing a full-bridge circuit. The left side represents the forward rotation control circuit. In this circuit, the N-channel power MOSFET in the upper left bridge arm is in a conducting state, with its gate receiving a high-level signal. The N-channel power MOSFET in the lower right bridge arm is controlled by the PWM signal, with the PWM signal input through its gate. The right side represents the reverse rotation control circuit. In this circuit, the N-channel power MOSFET in the upper right bridge arm is in a conducting state, with its gate receiving a high-level signal. The N-channel power MOSFET in the lower left bridge arm is controlled by the PWM signal, with the PWM signal input through its gate. Currently, brushless DC servo motors (BLDC) are commonly used in DC electric push-pull rods, and the PWM control circuit is designed for BLDC motors.

[0138] Figure 14 A half-bridge circuit is constructed using the EG2104 chip, with the low-level signal serving as the control signal. The three pins of NAND gate A are connected: the output pin is connected to the IN pin of the EG2104 chip, the input pin is the input terminal for the PWM signal, and the control pin is a low-level signal provided by the microcontroller's I / O port. Because the low-level signal blocks NAND gate A, the PWM signal cannot be transmitted to its output terminal. The N-channel power MOSFET in the upper arm of the half-bridge is in the ON state, with its gate at a high level; the N-channel power MOSFET in the lower arm of the half-bridge is in the OFF state, with its gate at a low level.

[0139] Figure 15A half-bridge circuit is constructed using the EG2104 chip, with the high-level signal serving as the control signal. The three pins of NAND gate A are connected: the output pin is connected to the IN pin of the EG2104 chip, the input pin is the input terminal for the PWM signal, and the control pin is a high-level signal provided by the microcontroller's I / O port. Since the high-level signal allows the PWM signal to be transmitted to its output terminal via the NAND gate, the N-channel power MOSFETs in the lower arm of the half-bridge are controlled by the PWM signal, with the PWM signal input from their gates. Similarly, the N-channel power MOSFETs in the upper arm of the half-bridge are also controlled by the PWM signal, with the PWM signal inverted by the NAND gate and input from their gates.

[0140] Figure 16 A practical circuit is constructed using two EG2104 chips, employing a full-bridge circuit composed of two half-bridge circuits. The left half-bridge is controlled by the microcontroller's I / O3 port, and the right half-bridge is controlled by the microcontroller's I / O4 port. When I / O3 outputs a low level "0" and I / O4 outputs a high level "1", the DC motor rotates forward; when I / O3 outputs a high level "1" and I / O4 outputs a low level "0", the DC motor rotates in reverse. PWM signals control the motor speed.

[0141] Figure 17 This is a wiring diagram of the I / O ports and control circuit of microcontroller #1. The two dashed boxes in the diagram are simplified schematic diagrams of the drive circuits for the three-section DC electric push-pull rods A5 and B12, respectively. Various components and lines have been hidden in each dashed box, showing only two EG2104 chips. The three-section DC electric push-pull rods A5 and B12 are of the same specification, have the same driving direction, and both use the same full-bridge circuit. I / O3 controls the left half-bridge of both full-bridge circuits simultaneously through NAND gate A; I / O4 controls the right half-bridge of both full-bridge circuits simultaneously through NAND gate B. A timer module of the microcontroller generates a PWM signal and outputs it to NAND gates A and B. I / O ports IO3 and IO4 control the rotation direction of the DC motors of the three-section DC electric push-pull rods A5 and B12. The duty cycle of the PWM signal generated by the timer module controls the speed of the three-section DC electric push-pull rods A5 and B12. IO1 is connected to the drive circuit of the three-section DC electric push-pull rod A5. When IO1 is low, the N-channel power MOSFET is turned off, thus shielding all control signals of the circuit. IO2 is connected to the drive circuit of the three-section DC electric push-pull rod B12. When IO2 is low, the N-channel power MOSFET is turned off, thus shielding all control signals of the circuit.

[0142] Figure 18 An ideal operating model for the extension stroke of an AC electric push-pull rod 18 is provided, which is based on Figure 11 The model shown. (And) Figure 11 The biggest difference, Figure 18An AC electric push-pull rod 18 is added, assuming no friction between the lead screw and slider of the AC electric push-pull rod 18. It should be noted that the slider of the AC electric push-pull rod 18 and the follower of the scissor lift platform 13 are integrated into a single design, and the AC electric push-pull rod 18 must satisfy the condition that its output power is zero. The follower and slider slide uniformly from position X1 to position X2 at a speed v1. The AC electric push-pull rod 18 extends uniformly from position X1 to position X2 at a speed v1; no force is generated between the AC electric push-pull rod 18 and the follower of the scissor lift platform 13, and its output power is zero. It should be noted that the uniform motion of the follower of the scissor lift platform 13 is... Figure 11 The abstract assumptions in the ideal model shown are not the actual situation. After adding the AC electric push-pull rod 18, it is ensured that no force is generated between the AC electric push-pull rod 18 and the follower of the scissor lift platform 13, thus ensuring that the original assumptions still hold.

[0143] The AC electric push-pull rod 18 consists of an AC drive motor, a lead screw, and accessories such as a slider. The slider and the follower of the scissor lift platform 13 are integrated into a single design. The speed of the AC motor driven by the lead screw is multiplied by the pitch of the lead screw, and the result is the theoretical extension speed v1 of the AC push-pull rod 18. The speed of the AC motor driven by the lead screw corresponding to the theoretical extension speed v1 of the AC electric push-pull rod is N1 (rpm). In an ideal state, the output power of the AC motor driven by the lead screw is zero, that is, it is in an unloaded state. According to relevant motor theory, the value of the ideal unloaded speed N1 (rpm) of the AC motor is the same as the value of the AC power supply frequency N1 (Hz) of the AC motor.

[0144] Microcontroller #1 controls the start and stop of the DC motor of the DC electric push-pull rod through a DC drive control circuit, and uses PWM speed regulation technology to control its speed. Microcontroller #2 controls the ultrasonic ranging circuit to detect the specific position of the open elevator car 7. Microcontroller #2 controls the start and stop of the AC motor of the AC electric push-pull rod through a frequency converter drive servo system.

[0145] Figure 19 An ideal operating model for the retraction stroke of an AC electric push-pull rod of 18 strokes is provided. This model is based on Figure 12 The model shown. (And) Figure 12 The biggest difference, Figure 19An AC electric push-pull rod 18 is added, assuming no friction between the lead screw and slider of the AC electric push-pull rod 18. It should be noted that the slider of the AC electric push-pull rod 18 and the follower of the scissor lift platform 13 are integrated into a single design, and the AC electric push-pull rod 18 must satisfy the condition that its output power is zero. The follower and slider slide uniformly from position X2 to position X1 at a speed v2. The AC electric push-pull rod 18 retracts uniformly from position X2 to position X1 at a speed v2; no force is generated between the AC electric push-pull rod 18 and the follower of the scissor lift platform 13, and its output power is zero. It should be noted that the uniform motion of the follower of the scissor lift platform 13 is... Figure 12 The abstract assumptions in the ideal model shown are not the actual situation. After adding the AC electric push-pull rod 18, it is ensured that no force is generated between the AC electric push-pull rod 18 and the follower of the scissor lift platform 13, thus ensuring that the original assumptions still hold.

[0146] The speed of the AC lead screw motor is multiplied by the lead screw pitch, resulting in the theoretical retraction speed v2 of the AC push-pull rod 18. The corresponding AC lead screw motor speed for the theoretical retraction speed v2 is N2 (rpm). Ideally, the AC lead screw motor outputs zero power, i.e., it is in an unloaded state. According to relevant motor theory, the ideal unloaded speed N2 (rpm) of the AC motor is the same as the AC power supply frequency N2 (Hz) of the AC motor.

[0147] Microcontroller #1 controls the start and stop of the DC motor of the DC electric push-pull rod through a DC drive control circuit, and uses PWM speed regulation technology to control its speed. Microcontroller #2 controls the ultrasonic ranging circuit to detect the specific position of the open elevator car 7. Microcontroller #2 controls the start and stop of the AC motor of the AC electric push-pull rod 18 through a frequency converter drive servo system.

[0148] Figure 20 It is a variable frequency drive servo system that drives AC motors. This control system is used to control... Figure 18 and Figure 19 The AC drive motor in the middle drives the lead screw to rotate. Figure 8 The rotary encoder 19 shown is an ABZ phase rotary encoder, which feeds back the actual speed of the AC drive motor to the frequency converter drive servo system via an EMM-PG01L PG card. The #2 microcontroller indirectly controls the AC electric push-pull rod 18 through the frequency converter drive servo system. This system consists of a frequency converter with a PG card slot, a PG card, a rotary encoder, and an AC motor, forming a closed-loop system. The #2 microcontroller's serial port 1 is connected to and communicates with the frequency converter's Modebus bus interface via a MAX485 circuit, sending relevant command information to the frequency converter. The frequency converter controls the AC drive motor of the AC electric push-pull rod 18, thereby controlling the advancement and retraction of the AC electric push-pull rod 18.

[0149] Figure 20 The image shows a typical example of a variable frequency drive servo system. It uses variable frequency technology to convert 50Hz AC power into DC power, and then inverts the DC power back into AC power of any frequency within the 0-50Hz range to output to the AC drive motor. According to... Figure 20 As shown, the 220V AC voltage is converted into three-phase AC output to the frequency converter via a phase-shifting circuit. The frequency converter is a Delta VFD-MH300 with a rated output power of 3.7KW. The AC drive motor has a rated power of 3.5KW, 2 poles, a rated current of 8.8A, a rated speed of 1800 rpm, and its windings are connected in a delta configuration with a rated voltage of 220V. To improve the stiffness of the mechanical characteristic curve of the AC drive motor, an IM FOCPG control mode, i.e., a closed-loop current vector control mode, is adopted. Figure 8 The rotary encoder 19 shown is an ABZ phase rotary encoder. The actual speed of the AC drive motor is fed back to the frequency converter through the EMM-PG01L PG card to form a closed-loop control.

[0150] Figure 20 The servo control system has three modes: speed control, position control, and torque control. Its operation and control settings are as follows: First, restore factory default values. Based on the factory default speed control mode of this inverter model, manually set parameter 3 (00-11) to field-guided vector control. Manually set parameter 1 (00-20), and the frequency of the inverter's output AC signal is written to the relevant control register by the host computer (i.e., microcontroller #2) via the Modebus bus interface. Manually set parameter 2 (00-21), and the motor control commands for forward, reverse, and stop rotation are written to the relevant control register by the host computer (i.e., microcontroller #2) via the Modebus bus interface. The serial communication baud rate uses the factory default value of 9600. Manually set parameter 03 (09-00) to the inverter address code. Manually set parameter 12 (09-04), and the inverter communication format adopts the RTU protocol, with the data format "8, N, 1" consistent with the microcontroller's communication data format. The ABZ encoder's 600 pulses per revolution is the factory default setting. Manually set parameter 10-00 to 1, and select ABZ rotary encoder as the encoder type. Manually set parameter 10-02 to 2, and set phase B to lead phase A by 90 degrees for positive.

[0151] The Delta VFD-MH300 inverter, model "VFD9A0MH43A", has a rated power of 3.7KW and a rated current of 10.5A. It features a "self-learning" capability for AC motors, with the motor in an unloaded state. Manual settings (00-02) are as follows: parameter 9, basic frequency 50Hz; parameter 50, maximum operating frequency 50Hz; parameter 50, rated motor frequency 50Hz; parameter 220V, rated motor voltage 380V. The inverter actually provides 220V, while the AC drive motor uses a delta connection. Parameter 1, manual setting (05-00), dynamic test with the motor disconnected from the load. Parameter 8.8, rated motor current 8.8A; parameter 3.5, rated motor power 3.5KW. Manually set parameter 05-03 to 1800, setting the motor's rated speed to 1800 rpm. Manually set parameter 05-04 to 2, setting the motor's pole count to 2. Manually set parameter 05-05 to 3.8, setting the motor's no-load current to 3.8A ≈ 8.8A * 40%. Manually set parameter 05-00 to 6, executing asynchronous motor self-learning (0500=6), i.e., flux curve self-learning, to obtain parameters such as stator resistance, rotor resistance, mutual inductance, leakage inductance, and no-load current.

[0152] Set the operating power frequency of the AC motor. The setting method is as follows: Set the operating power frequency of the AC motor to N Hz, and write the hexadecimal code of the value 200N into the control register at address 2001H. Assuming N=15, the microcontroller #2 sends the first group of hexadecimal data "03 06", "20 01", "0B B8", and "D5 6A" according to the RTU protocol. "20 01" points to the control word register address 2001H, and "0B B8" is the hexadecimal code of the value 3000, which means 30%, i.e., 50Hz * 30% is 15 Hz. Writing "0B B8" into the control register at address 2001H sets the AC motor operating power frequency to 15 Hz. The "03" in the "03 06" data corresponds to the manual setting of parameter 09-00 to 03, and is the inverter address code; the "06" in the "03 06" data executes the forward rotation command written to the control word register. "D5 6A" is the check code. Microcontroller #2 sends this set of data. After the AC motor starts, it will rotate in the direction set by the control register at address 2000H. The motor's operating power frequency is 15 Hz.

[0153] The AC motor's rotation direction is set to forward. Microcontroller #2 sends the second set of hexadecimal data "03 06", "20 00", "00 12", and "03 E5" according to the RTU protocol. "20 00" points to address 2000H in the control word register, and "00 12" is the AC motor forward rotation command. The "03" in "03 06" corresponds to the inverter address code, which is the manual setting of parameter 09-00 to 03; the "06" in "03 06" executes the forward rotation command and writes it to the control word register. "03 E5" is the checksum. Microcontroller #2 sends this set of data, confirms the AC motor's rotation direction as forward, and starts the motor.

[0154] The AC motor's rotation direction is set to reverse. Microcontroller #2 sends the third set of hexadecimal data "03 06", "20 00", "00 22", and "03 F1" according to the RTU protocol. "20 00" points to address 2000H in the control word register, and "00 22" is the AC motor reverse operation instruction. The "03" in "03 06" corresponds to the manually set parameter 09-00 being 03, representing the inverter address code; the "06" in "03 06" executes the reverse operation instruction and writes it to the control word register. "03 F1" is the checksum. Microcontroller #2 sends this set of data, confirming the AC motor's rotation direction is reverse and starting the motor.

[0155] The AC motor is set to stop. The main control microcontroller sends the fourth set of hexadecimal data "03 06", "20 00", "00 01", and "42 28" according to the RTU protocol. "20 00" points to address 2000H in the control word register, and "00 01" is the AC motor stop command. The "03" in "03 06" corresponds to the inverter address code when the parameter is manually set to 03 (09-00); the "06" in "03 06" executes the stop command and writes it to the control word register. "42 28" is the checksum. Microcontroller #2 sends this set of data, causing the AC motor to stop.

[0156] Figure 21 This is a schematic diagram showing the location of the cutting line. Figure 1 The front view of the elevator section of the structure shown is... Figure 2 The section was cut, and the specific location of section C was marked.

[0157] Figure 22 for Figure 2 The C-section structural diagram shows the distribution of button group 16 on the cross-section. Button group 16 has four buttons on each of the first and second floors (top floors). The four control buttons on the second floor are distributed as follows: Figure 22As shown, their functions are as follows: Button A is the descent request button, Button B is the door open request button, Button C is the elevator call request button, and Button D is the door close request button. Buttons A, B, and C are connected to microcontroller #3, and button D is connected to microcontroller #5. Microcontroller #3 detects the state changes of buttons A, B, and C through its I / O ports. Microcontroller #5 detects the state changes of button D through its I / O port. It should be noted that the distribution diagram of the four control buttons on the first floor is the same as that on the second floor. Figure 22 The layout is similar, with the following four control buttons: Button A is the ascending request button, Button B is the door opening request button, Button C is the elevator call request button, and Button D is the door closing request button. Buttons A, B, and C are connected to microcontroller #3, and button D is connected to microcontroller #4. Microcontroller #3 detects the state changes of buttons A, B, and C through I / O ports. Microcontroller #4 detects the state changes of button D through I / O ports. Microcontroller #3 is the main control microcontroller (see...). Figure 39 ), 4# microcontroller is the single-chip microcontroller for the elevator door control of one floor (see Figure 39 ), 5# microcontroller is a two-story elevator door control microcontroller (see Figure 39 ).

[0158] Figure 23 This is a 3D structural diagram of an open-type elevator car 7. The open-type elevator car 7 has two pairs of threaded holes on each side for fixing compressed gas spring A 8 and compressed gas spring B 11, respectively. Each corner of the floor plate of the open-type elevator car 7 has a circular hole; only two holes are visible in the diagram, the other two are not. The four circular holes correspond to... Figure 4 The scissor lift platform 13 shown has four threaded holes. Four bolts are used to secure the open elevator car 7 to the scissor lift platform 13. The mechanical connection method of the bolts is described in [details omitted]. Figure 25 As shown.

[0159] Figure 24 The diagram shows a three-view drawing of pedal 10, with a circular hole at each corner corresponding to a circular hole at each corner of the open elevator car floor. Pedal 10 has four pads, which are piezoresistive sensors that interact with the floor of the open elevator car 7. Based on the principle of action and reaction, the four pads of pedal 10 are piezoresistive sensors used to measure the load-bearing capacity of the floor of the open elevator car 7. A shock-absorbing device, similar to a spring mattress, may be placed above pedal 10; such accessories are not shown in the accompanying drawings.

[0160] Figure 25This is a partial cross-sectional view of the mechanical connection between the footplate 10, the floor of the open elevator car, and the surface of the scissor lift platform. A round hole at the corner of the footplate fits onto a bolt cap; the inner diameter of the hole is slightly larger than the outer diameter of the bolt cap. Bolts secure the floor of the open elevator car to the surface of the scissor lift platform. There is a gap between the footplate 10 and the floor of the open elevator car.

[0161] Figure 26 A simplified diagram of a scissor lift model, where θ is the angle between the scissor arm and the horizontal line. Following the ideal operating model described earlier, the horizontal velocity Vx is constant. During the upward stroke, Vx is directed to the right, Vx = v1. Corresponding to this velocity value, the ideal no-load speed of the AC motor is N1 (rpm), and the AC electric push-pull rod starts without load. Following the ideal operating model described earlier, the horizontal velocity Vx is constant. During the downward stroke, Vx is directed to the left, Vx = v2. Corresponding to this velocity value, the ideal no-load speed of the AC motor is N2 (rpm), and the AC electric push-pull rod starts without load.

[0162] According to the ideal model described above, the vertical speed Vy is a variable speed motion, Vy = Vxcot(θ). During the upward stroke, the vertical speed Vy is a gradual deceleration process. The AC motor output power is zero, and under the combined force of various forces, the scissor lift platform maintains a constant upward speed of Vxcot(θ), rising in a variable speed manner.

[0163] According to the operation mode of the ideal model mentioned above, the vertical speed Vy is a variable speed motion, Vy=Vxcot(θ). The vertical speed Vy during the descent is a gradual increase process. The output power of the AC motor is zero. Under the combined action of various forces, the scissor lift platform always maintains the descent speed Vxcot(θ) and descends in a variable speed manner.

[0164] In actual operation, the output power of an AC motor is not zero; the higher the output power, the better. In the ideal model of the rising stroke, the AC motor frequency parameter is set to N1, and in the ideal model of the falling stroke, the AC motor frequency parameter is set to N2. When the AC motor frequency exceeds the rated frequency by 50Hz, its output power decreases with increasing frequency. Therefore, the AC motor frequency parameter in the rising stroke should be relatively large, but in practice, the AC motor frequency parameter cannot exceed N1 and N2, and must be lower than the rated frequency of 50Hz. In reality, the lower the AC motor frequency, the lower its output torque. However, in vector control mode, when the Delta inverter is set to a low frequency, the three-phase motor can still output a large torque. According to relevant technical data, in vector control mode, when the heavy-load starting frequency of the Delta inverter is set to 0.5Hz, it can provide 200% of the starting torque. The AC motor frequency parameter in the rising stroke is tuned in the range (0, N1), taking the largest reasonable value possible to achieve a larger rising speed. The AC motor frequency parameter in the falling stroke is tuned in the range (0, N2).

[0165] Figure 26 The drive structure of the scissor lift model consists of three parts. The AC electric push-pull rod 18 and the scissor lift platform 13 form a complete lifting drive system, with the open elevator car 7 fixed on top. The extension and retraction of the AC electric push-pull rod 18 is completely synchronized with the lifting and lowering of the scissor lift platform 13. Three DC electric push-pull rods are positioned on both sides of the scissor lift platform 13, acting via gas springs on both sides of the open elevator car 7. The extension and retraction of these three DC electric push-pull rods are in the same direction as the lifting and lowering of the scissor lift platform 13, but not necessarily synchronously. The AC electric push-pull rod is the central core drive component, while the three DC electric push-pull rods are auxiliary drive components, one of their functions being to help the AC electric push-pull rod overcome mechanical dead zones.

[0166] The scissor lift platform 13 has a dead zone; when the angle θ is zero, it is in a mechanical dead zone state. To overcome this state, the initial position angle of θ cannot be zero. During operation, the smaller the angle θ of the AC motor, the closer it is to the dead zone, resulting in lower output torque and a higher risk of stalling. Conversely, the larger the angle θ, the further it is from the dead zone, and the higher the output torque. In ideal operating conditions, the entire load is borne by the DC motor drive system, while the AC motor is in an unloaded state, hence the term "no-load start." In actual operation, generally, the DC drive system provides driving force exceeding the actual load during startup to assist the AC motor in starting; however, if the load is too heavy, the DC drive system outputs its maximum force to reduce the load borne by the AC motor drive system, achieving a light-load start. In summary, the AC drive system has three starting methods in actual operation: assisted start, light-load start, and no-load start, avoiding heavy-load starts. In cases of severe overload, starting should be avoided until the load is less than the rated load. The ideal operating mode discussed above refers to a no-load start.

[0167] The thrust of the open-type elevator car 7 originates from the horizontal AC electric push-pull rod and the vertical three-section DC electric push-pull rod, thus there is a problem of cooperative operation between the power systems. Based on the previous Figure 10 test model for measuring the operation time of the lifting system powered by the three-section DC electric push-pull rod, under the condition of carrying a rated load, the actual measured time is obtained, and the average speed v1 is calculated by dividing the displacement by the time. The speed v1 is the average speed of the follower of the scissor lifting platform 13 under the action of the vertical three-section DC electric push-pull rod. Then the AC motor frequency of the AC electric push-pull rod 18 is set to N1, that is, the ideal no-load rotational speed N1 (r / s) of the AC motor of the AC electric push-pull rod 18. The operation of the scissor lifting platform 13 cannot be in an ideal state, and the output power of the AC electric push-pull rod 18 cannot remain zero but keeps changing. In order to make the AC electric push-pull rod 18 output the maximum thrust as much as possible during the ascending stroke, the actually tuned AC motor frequency parameter is not greater than N1. The lifting of the scissor lifting platform cannot be a regular and predictable change process, but a complex variable speed process. In this case, the horizontal AC electric push-pull rod and the vertical three-section DC electric push-pull rod can only maintain synchronization at a certain moment, that is, the starting moment, and it is difficult to maintain synchronization throughout the whole process. During the whole operation process of the ascending stroke, the ascending speed of the scissor lifting platform shall be ensured by setting the working power supply frequency parameter of the AC motor to a relatively large value Z1 (10<Z1<N1). In order to make the AC electric push-pull rod 18 output greater thrust to push a heavier load and further realize starting, the working power supply frequency parameter of the AC motor is set to a relatively small value Z0 (10≤Z0<Z1). In principle, the working power supply frequency parameter of the AC motor cannot exceed the rated frequency, because after the working power supply frequency parameter of the AC motor exceeds the rated frequency, its output power will decrease. During the whole operation process of the descending stroke, that is, the whole operation process of the contraction stroke of the three-section DC electric push-pull rod, it is ensured that at any moment, the actual stroke of the third section push rod of the three-section DC electric push-pull rod is greater than the actual stroke of the scissor lifting platform 13, and it is ensured that the pressure difference between the cylinder air pressure of the compressed gas spring and the external atmospheric pressure during the whole stroke is not greater than the specified positive pressure value. The so-called specified positive pressure value refers to the initial value of the pressure difference between the cylinder air pressure of the compressed gas spring and the external atmospheric pressure before the operation of the ascending stroke and before the DC motor acts. During the whole operation process of the descending stroke, the AC motor frequency parameter is tuned to the Z2 value and the Z3 value, the Z2 value is a downward float of the N2 value, and the Z3 value is tuned in the interval (0, 10). The Z2 value and the Z3 value allow floating within a certain range according to the actual tuning situation.

[0168] Figure 26The relevant parameters are derived from an ideal model under ideal no-load conditions. For example, the operating power frequency parameter of the AC motor is set to N1 during the upward stroke. The operating power frequency parameter of the AC motor must be adjusted according to the actual operating conditions during the upward stroke. The AC motor starts at zero speed, and after several seconds or tens of seconds, the speed stabilizes (the speed changes slowly or remains constant). The difference between the speed (rpm) and the set value (Hz) of the AC motor's operating power frequency parameter is the slip, and the ratio of the slip to the set value is the slip ratio. At the beginning of the upward stroke, the AC motor frequency parameter is set to N1. After placing a load less than half the rated load in the elevator car, the elevator is started and the slip ratio is measured. After the measurement is completed, the operation is stopped. This process is repeated, but with an appropriate increase in weight each time. When the slip ratio approaches the critical slip ratio, before repeating the operation again, the set value of the AC motor's operating power frequency parameter is reduced to ensure that the slip ratio is below the critical slip ratio after the next repetition. When the weight of the object placed in the elevator car reaches twice the rated load, and the slip rate is below the critical slip rate after operation, the current AC motor operating power frequency parameter setting value is Z1. Generally, the designer has determined the maximum load (i.e., the rated load), and the above operation is repeated until the weight of the object placed in the elevator car reaches the maximum load (i.e., the rated load), and the slip rate is below the critical slip rate after operation. Then, the current AC motor operating power frequency parameter setting value is Z0. If the designer has not determined the maximum load (i.e., the rated load), the AC motor operating power frequency parameter setting value is 10, i.e., Z0 = 10. At the beginning of the upward stroke, the AC motor operating power frequency parameter is set to 10. After placing a weight twice the rated load in the elevator car, the elevator is started and the slip rate is measured. After the measurement is completed, operation is stopped. This operation is repeated, but an appropriate weight is added before each repetition. When the slip rate approaches the critical slip rate, the weight addition is stopped. At this point, the weight carried in the elevator car is the maximum load, i.e., the rated load, and the corresponding AC motor operating power supply frequency parameter Z0 = 10. According to relevant technical data, Delta inverters, in vector control mode, can provide 200% starting torque when the heavy-load starting frequency is set to 0.5Hz. In engineering applications, the output frequency of the Delta inverter, i.e., the AC motor operating power supply frequency parameter, is set to 0.5Hz to meet the requirements of heavy-load starting applications; however, considering that the scissor lift platform's lifting speed is too slow when the AC motor operating power supply frequency parameter is set to 0.5Hz, while taking efficiency into account, the AC motor operating power supply frequency parameter is set to 10, or a value greater than 10. If the designer determines the maximum load, the maximum load cannot exceed the rated load when the AC motor operating power supply frequency parameter is set to 10. In summary, the above is the process and method for setting the AC motor operating power supply frequency parameters Z0 and Z1.Z1 is the set value for the AC motor's operating power frequency when the load does not exceed twice the rated load, and Z0 is the set value for the AC motor's operating power frequency when the load reaches the maximum load. In principle, the load should not exceed the maximum load, i.e., the approved load, as this can easily lead to AC motor malfunction or abnormal operation.

[0169] During the descent stroke, the operating power frequency parameter of the AC motor is set to N2. The operating power frequency parameter of the AC motor must be adjusted according to the actual operating conditions. The descent stroke is divided into three stages: the first stage is from the starting point to the point where the distance to the end point is approximately L, where L is a specific distance. The specific distance L is maintained to avoid excessive compression of the air spring, and this specific distance L is specifically defined later; the second stage is a 10-second pause; the third stage continues descent until the end point. It should be noted that: during the descent stroke, the scissor lift platform 13 must always maintain a lagging state. When the DC electric push-pull rod retracts to the end point, the distance between the scissor lift platform and the end point is the specific distance L or approximately equal to the specific distance L; throughout the process, the cylinder of the air spring should be kept under negative pressure as much as possible. If positive pressure occurs during operation, the pressure difference must be ensured not to exceed the agreed positive pressure value to avoid coordination abnormalities. There are two main ways to avoid positive pressure during operation: first, by increasing the theoretical working stroke of the air spring; second, by reasonably setting the AC motor frequency parameter setting value. Once the compression gas spring is designed and manufactured, its specifications and parameters cannot be changed, nor can its working stroke. After the descent stroke begins, microcontroller #1 first drives the DC motor to reverse, the three-section DC electric push-pull rod retracts, and the cylinder pressure of the compression gas spring changes from positive to negative. Once microcontroller #1 detects that the current pressure difference is equal to or lower than the negative pressure lower limit, it sends a coordination signal to microcontroller #2 and calls the DC motor drive subroutine (see program flowchart). Figure 35 The #2 microcontroller enters the main program, sets the AC motor's operating power frequency parameter to N2, and starts the AC motor in reverse. If the relevant conditions are met—that is, during the retraction of the three-section DC electric push-pull rod, the actual stroke of the scissor lift platform 13 always lags behind the retraction stroke of the DC electric push-pull rod and operates normally—and the set value of the operating power frequency parameter Z2 is equal to N2, the test stops. If the conditions are not met, the test stops and proceeds to the next test. During the next test, initialization is performed, the AC motor's operating power frequency parameter is reduced, and the previous operation is repeated. If the conditions are not met, the test stops and proceeds to the next test, further reducing the AC motor's operating power frequency parameter. This process is repeated until the conditions are met, and the currently set AC motor operating power frequency parameter is the set value Z2. In summary, the above describes the process and method for setting the AC motor's operating power frequency parameter Z2.

[0170] During the third stage of the descent stroke, the AC motor's operating power frequency parameter Z3 can be directly set to 0.5 Hz. According to relevant technical data, Delta inverters, in vector control mode, can provide 200% starting torque when the heavy-load starting frequency is set to 0.5 Hz. This setting is used to generate strong torque during heavy-load starts and is also applicable to the design of this utility model. The torque acts on the lead screw, and the rotation of the lead screw indirectly acts on the scissor lift platform, causing the scissor lift platform 13 to descend and compress the compressed air spring, increasing the pressure difference between its cylinder and the external atmospheric pressure (pressure differential) to the agreed positive pressure value. If the pressure differential cannot be increased to the agreed positive pressure value, the angle θ between the scissor arm of the scissor lift platform and the horizontal line needs to be adjusted. The AC motor's operating power frequency parameter Z3 can be set to 0.5 or other values. However, regardless of the setting, it must ensure the generation of strong torque. Under heavy-load pushing or pulling conditions, the AC motor's operating power frequency is usually below 10 Hz. In summary, the above is the setting process and method for the AC motor's operating power frequency parameter Z3.

[0171] In actual systems, due to the presence of multiple drive components, coordination between these components is difficult. Completely synchronous operation throughout the entire process is unattainable; synchronization can only be maintained at a specific moment, namely the start-up instant. To ensure synchronous operation of the three-section DC electric push-pull rods (sections A5 and B12) on both sides of the open-type elevator car 7, their drive circuits share the same circuit, and their specifications are ensured to be consistent during manufacturing. Similarly, the two compressed air springs (compressed air spring A8 and B11) are manufactured with consistent parameters. Since the AC drive system and DC drive components are not necessarily completely synchronized throughout the entire operation, their coordination relies on the adaptability of relevant components and the adaptive design of the relevant control system, which will be discussed later.

[0172] When the actual system is in its initial state, the pressure difference between the compressed air spring cylinder and the current atmospheric pressure is the positive pressure convention value. The definition of the positive pressure convention value will be described later. When the system returns to its initial state after the upward and downward strokes, the pressure difference between the compressed air spring cylinder and the current atmospheric pressure returns to the positive pressure convention value. When the open elevator car 7 is unloaded, its weight is at its minimum. Before the downward stroke ends, the compressed air spring must be compressed to its initial state, which cannot be accomplished by the weight of the open elevator car 7 alone. The AC motor reverses to drive the slider, thereby generating tension. When the angle θ is zero, it cannot be converted into pressure to compress the compressed air spring. The initial value of the angle θ is set to a specific value to ensure that the AC motor driving force is converted into pressure and the weight of the open elevator car 7 forms a resultant force to compress the compressed air spring to its initial state, that is, the pressure difference between the compressed air spring cylinder and the current atmospheric pressure returns to the positive pressure convention value. It should be noted that Delta inverters use IM FOCPG control mode, which is a closed-loop current vector control mode. In this mode, even if the AC motor frequency parameter setting value Z3 is close to zero, the AC motor still has a large torque output.

[0173] also, Figure 10 The diagram shows a test model for measuring the running time of a lifting system powered by a three-section DC electric push-pull rod. Under rated load, the measured time is used to calculate the average speed v1 by subtracting time from the position value. During the operation of this test model, the initial state of the compressed gas spring is the cylinder pressure difference, i.e., the difference between the actual cylinder pressure and the current atmospheric pressure, which corresponds to the rated load. When the open elevator car 7 is stationary with the rated load, the current pressure difference, i.e., the difference between the cylinder pressure generated by the compressed gas spring and the atmospheric pressure, corresponds to the rated load. In actual operation, the initial value of the cylinder pressure difference of the compressed gas spring is the positive pressure convention value; however, during the test of the average speed of the scissor lift platform's follower, the initial value of the cylinder pressure difference of the compressed gas spring is the pressure difference corresponding to the rated load. The positive pressure convention value is usually higher than the pressure difference corresponding to the rated load, which will be explained later. The rated load and the positive pressure convention value are shown in the characteristic curve of the compressed gas spring (see...). Figure 30 The calibration is performed on the vertical axis of the coordinate system.

[0174] Figure 26The design idealizes and abstracts the actual motion of the mechanism, particularly neglecting friction. In reality, the push-pull rod uses lead screws or worm gears with T-shaped teeth and small pitch, resulting in significant friction and a self-locking function. When the DC or AC motor stops, the elevator car stops moving due to lack of power. The self-locking function of the electric push-pull rod's transmission nut effectively prevents slippage, avoiding displacement of the elevator car when the motor stops. The related calculations and designs neglected the factor of friction. This neglect of numerous factors leads to parameters in the theoretical derivation that require actual debugging and repeated adjustments.

[0175] Figure 27 The diagram shows the two views of the gas spring: the front view, the top view, and the cross-sectional view at section D. As mentioned earlier, gas spring A8 and gas spring B11 are manufactured with all parameters consistent. The theoretical working stroke of the gas spring should be greater than or significantly greater than the deviation between the lifting stroke of the scissor lift platform and the lifting stroke of the third push rod of the three-section DC electric push rod. The maximum working pressure (commonly known as the maximum working pressure) of the gas spring cylinder should be greater than the actual pressure it generates under the maximum force of the three-section DC electric push rod.

[0176] The compressed gas spring has two T-joints at its tail end, each T-joint having a pair of round holes. The two pairs of round holes of the two T-joints correspond to... Figure 23 Two pairs of threaded holes are shown on one side of the open elevator car. Bolts secure the T-joint to one side of the open elevator car, see... Figure 7 and Figure 9 As shown. The other end of the compressed air spring uses a U-shaped connector. The mechanical connection between the U-shaped connector and the end of the three-section DC electric push-pull rod is shown in the figure. Figure 29 .

[0177] The compressed gas spring consists of a telescopic rod (piston rod), a cylinder, a U-shaped connector, and a T-shaped connector. The cylinder and tail end are integrated into a single design. The cylinder includes a piston and sealing elements, and a built-in piezoresistive sensor is used to measure the internal air pressure. The length shown in the diagram is not related to the actual length; the thick dashed line represents the extension in the length direction. The actual cylinder is longer than the cylinder shown in the diagram, with an extended tail end secured by two T-shaped connectors. A pair of compressed gas springs, namely compressed gas spring A8 and compressed gas spring B11, are fixed to both sides of an open elevator car.

[0178] The primary function of a gas spring is to prevent hard impacts and also to provide slight cushioning against hard drag. The cross-sectional view at section D shows the tail end of the gas spring, which is elongated compared to a standard gas spring. The tail end is integrally designed and cast with the cylinder. The elongated tail end facilitates the fixation of the gas spring to both sides of an open elevator car.

[0179] Elevator operation is divided into two phases: ascending and descending. During the ascending phase, if the travel of the three-section DC electric push-pull rod exceeds the travel of the lifting platform, or during the descending phase, if the travel of the lifting platform exceeds the travel of the three-section DC electric push-pull rod, the compressed gas spring will be excessively compressed, causing a rapid increase in air pressure within its cylinder. When the extension travel of the three-section DC electric push-pull rod during the ascending phase is less than the travel of the lifting platform, or during the descending phase, if the travel of the lifting platform is less than the retraction travel of the three-section DC electric push-pull rod, the compressed gas spring adaptively compensates for the travel deviation through deformation. However, the deformation of the compressed gas spring is limited; when dragging occurs, negative pressure is generated in the compressed gas spring cylinder. The compressed gas spring has relatively low tensile strength, thus preventing excessive dragging.

[0180] Figure 28 This describes the structure at the end of a three-section DC electric push-pull rod. The last section of the three-section electric push-pull rod is machined into a multi-step rotating shaft. The first step shaft is a round shaft, and the second step shaft is a rectangular shaft with a drilled round hole whose diameter is slightly larger than the diameter of the bolt rod. The second step shaft is hinged to the U-shaped joint of the compressed gas spring.

[0181] Figure 29 This is a partial cross-sectional view of the mechanical connection between the end of the three-section electric push-pull rod and the compressed gas spring. The end of the electric push-pull rod is inserted into the U-shaped connector of the compressed gas spring and secured with nuts and bolts. Special note: In... Figure 9 In the power entity model shown, the U-shaped joint between the end of the electric push-pull rod and the compressed gas spring is fastened with a nut and a long bolt, and the position of the ultrasonic ranging sensor 9 is moved to directly above the end of the bolt.

[0182] Figure 30 This is the characteristic curve of a compression gas spring. The pressure difference is the difference between the actual air pressure and the external atmospheric pressure. Normal atmospheric pressure fluctuates between 980 Pa and 1040 Pa. The horizontal axis represents the travel, and the intersection of the horizontal and vertical axes is the origin. The air pressure difference corresponding to the origin is zero, and the load corresponding to the origin is zero, i.e., unloaded. The vertical axis represents the load. The load and air pressure difference are mutually corresponding during the spring's extension and contraction. The "maximum negative pressure" is not the air pressure difference value, but rather the load corresponding to the "maximum negative pressure," and similarly, the "lower limit of negative pressure" is the load corresponding to the "lower limit of negative pressure."

[0183] The maximum force of the push rod is marked on its vertical axis. This maximum force is the maximum output force of the three-section DC electric push rod, and it is required that the maximum force of the three-section DC electric push rod is lower than the ultimate load. The pressure difference between the air pressure generated by the three-section DC electric push rod acting on the compression gas spring at its maximum force and the current external atmospheric pressure is the "upper limit of positive pressure." The "upper limit of positive pressure" is marked on the vertical axis of the compression gas spring's characteristic curve, corresponding to the maximum force of the three-section DC electric push rod. The ultimate load is the maximum load that the compression gas spring can withstand, which is unrelated to the maximum force of the three-section DC electric push rod, but is related to the materials used in the various components of the compression gas spring. In principle, the ultimate load must be greater than the maximum force of the three-section DC electric push rod. When the compression gas spring withstands the ultimate load, the pressure difference between the air pressure generated by its cylinder and the current external atmospheric pressure is the "maximum positive pressure." The "maximum positive pressure" is marked on the vertical axis of the compression gas spring's characteristic curve, corresponding to the ultimate load that the compression gas spring can withstand.

[0184] The higher the motor speed of a three-section DC electric linear actuator, the lower its thrust. When the three-section DC electric linear actuator outputs its maximum force, its motor speed approaches zero, and the motor's drive current is extremely high, posing a risk of stalling. If stalling occurs, the drive circuit of the three-section DC electric linear actuator motor will burn out. As mentioned earlier, the DC motor drive circuit is directly controlled by the #1 microcontroller using PWM speed regulation. To prevent the drive circuit from burning out due to the extremely high drive current, when the pressure difference between the compressed air spring and the current external atmospheric pressure reaches or approaches the upper limit of positive pressure, the PWM duty cycle is set to zero, causing the current to approach zero. The DC electric linear actuator stops and enters a mechanical self-locking state. Because the current approaches zero, the drive circuit is prevented from burning out. After power is cut off, due to the spring's elasticity, the upward thrust remains at its current value.

[0185] Figure 30 The characteristic curve of a medium-compression gas spring contains a linear region. Springs are typically used for measurement; during measurement, they deform under force. The change in force and the deformation are approximately linear within this region, known as the theoretical working stroke. This linear region is related to the spring material and parameter design, and is also called the design stroke. Within this stroke, the spring's displacement and the applied force are linearly related. The rated load corresponds to a pressure difference value within this linear region, often close to its upper limit. The rated load corresponds to a pressure difference value that is often lower than the agreed-upon positive pressure value. This agreed-upon value is determined by certain specifications or agreements. In this invention, the gas spring is not used for measurement. During the push rod's advancement, the compressed spring is in a compressed state, i.e., it operates in a high-pressure compression region, which is approximately linear. The upper limit of this linear region is the upper limit of the positive pressure, and the lower limit is lower than the agreed-upon positive pressure value, i.e., the minimum preload of the push rod. The agreed-upon positive pressure value is located within the linear region of the high-pressure compression region, and the spring's rated load is located within the linear region of the theoretical working stroke. Therefore, the spring's rated load is usually lower than the agreed-upon positive pressure value.

[0186] The compression spring is an adaptive adjustment element that adjusts itself during propulsion. The DC electric push-pull rod extends faster than the lifting platform's ascent speed, compressing the gas spring and increasing the pressure difference. During operation, the faster push-pull rod bears a greater load. Due to the adaptive nature of the electric push-pull rod, its extension and retraction speed is inversely proportional to the load. If the AC electric push-pull rod bears a heavier load, its propulsion speed decreases, and the lifting platform's ascent speed is slower than the DC electric push-pull rod's extension speed. This causes the gas spring to be further compressed by the DC electric push-pull rod, resulting in a greater force acting on the open elevator car. This directly leads to the adaptive adjustment of the load-sharing ratio by each drive system. Especially for the DC electric push-pull rod, whose control system is open-loop, the output torque increases and the rotational speed decreases when it encounters resistance.

[0187] The scissor lift platform adaptively adjusts during its ascending operation. During ascent, the scissor lift platform's stroke exceeds the stroke of the three-section electric DC push rod. The compression spring is designed to theoretically have a stroke greater than or significantly greater than the deviation between the scissor lift platform's stroke and the stroke of the third section of the three-section electric DC push rod. The compression spring compensates for this difference in stroke through its rebound deformation.

[0188] The scissor lift platform undergoes adaptive adjustment during operation. However, if the scissor lift platform lags behind, its stroke will be less than the stroke of the three-section electric DC push-pull rod. The compressed air spring itself cannot adaptively adjust for this, but this situation will be accompanied by excessive compression or stretching of the spring, causing the pressure difference between the internal air pressure of the spring cylinder and the external atmospheric pressure to exceed the upper limit of positive pressure or fall below the lower limit of negative pressure. The compressed air cylinder has a built-in piezoresistive sensor to measure the internal air pressure; this sensor is part of the differential pressure detection circuit in the DC motor control system. To address this issue, the DC motor control system must be designed with adaptive adjustment capabilities.

[0189] Figure 30 The specific distance L is a design value independent of the characteristics of the gas spring. The gas spring deforms as its cylinder rises from a predetermined positive pressure value to its upper positive pressure limit. The specific distance L is defined as twice or slightly more than twice this deformation. During the descent stroke, the scissor lift platform maintains a lag, meaning its descent stroke is less than the retraction stroke of the three-section electric DC push rod. When the three-section electric DC push rod retracts to its end point, the deviation between its retraction stroke and the descent stroke of the scissor lift platform is a specific distance L or slightly more than a specific distance L, thus ensuring that the gas spring is not over-compressed.

[0190] The vertical axis of the curve is labeled "Spring Rated Load". If the spring rated load matches the rated load of the three-section DC electric actuator, the spring rated load is unique and corresponds to the rated load of the three-section DC electric actuator. When the load on the three-section DC electric actuator is the rated load, its propulsion speed is the full-load speed. Figure 10 The rated load shown is based on this condition, utilizing Figure 9 The rated load measured by the dynamic solid model shown. Figure 10 The rated load shown is actually borne by the floor plate of the open elevator car 7. If the rated load of the spring matches the rated load of the three-section DC electric actuator, the three ( Figure 10 The rated load (rated load of the three-section DC electric actuator, rated load of the spring) shown corresponds one-to-one with the cylinder air pressure generated by the compressed air spring under its rated load. If the rated load of the spring does not match the rated load of the three-section DC electric actuator, the rated load of the spring should be greater than the rated load of the three-section DC electric actuator. Figure 10 The air pressure of the compressed air spring cylinder corresponding to the rated load shown must be within the theoretical working stroke.

[0191] Figure 31 The circuit system is based on microcontroller #1. Microcontroller #3 is the host computer, while microcontrollers #1 and #2 are slave computers of microcontroller #3. Microcontroller #3 communicates with microcontroller #2 to obtain ultrasonic ranging results and thus determine the position of the open-type elevator car. Each microcontroller has an operating status register and a fault status register; microcontroller #2, in addition to its operating and fault status registers, also has a coordination status register and a register for storing ultrasonic ranging results. Microcontroller #3 has a fault status register array composed of several fault status registers. Unit 1 of this array stores the fault status register value of microcontroller #1, unit 2 stores the fault status register value of microcontroller #2, unit 4 stores the fault status register value of microcontroller #4, and unit 5 stores the fault status register value of microcontroller #5. The fault status register array of microcontroller #3 has a special function. The binary value stored in this unit has a special meaning. The first bit of the binary value corresponds to microcontroller #1. If this bit is 0, it means that microcontroller #1 is normal. Otherwise, it is faulty. And so on. The second bit corresponds to microcontroller #2, the third bit corresponds to microcontroller #3, the fourth bit corresponds to microcontroller #4, and the fifth bit corresponds to microcontroller #5.

[0192] Microcontroller #3 acts as the host computer, and the startup command originates from it. Microcontroller #3 sets its own operating status register to "Run" and its travel status to "Up" or "Down". If the open-air elevator car 7 is on the ground floor, the travel status in microcontroller #3's operating status register is set to "Up"; if the open-air elevator car 7 is on the top floor, the travel status in microcontroller #3's operating status register is set to "Down". Microcontroller #3 then broadcasts the set value of its own operating status register to the operating status registers of all other microcontrollers; this is the startup command.

[0193] Microcontroller #3 is the host computer, and the start command originates from microcontroller #3. Microcontroller #3 communicates with microcontroller #2 to obtain the ultrasonic ranging results, and then determines the position 7 of the open elevator car. Microcontrollers #3 and #2 are allowed a certain margin of error in the position of the open elevator car 7. Within this error range, if the open elevator car's position 7 is located on the top or bottom floor, microcontroller #3 can send the start command; this is a necessary condition for sending the start command. Additionally, the elevator door on the top or bottom floor must be closed; otherwise, the start command cannot be sent.

[0194] Figure 31 This is a circuit system with microcontroller #1 as its core. Microcontroller #3 is the host computer, and the termination command originates from microcontroller #3. The running status register of microcontroller #3 is set to "stop" (terminated), and it broadcasts this setting value to the running status registers of all other microcontrollers; this is the termination command. The termination command is sent by the host microcontroller #3 in cases such as the end of the rising stroke, the end of the falling stroke, or a fault (abnormality) during operation. Upon receiving the command, each microcontroller processes it accordingly and then enters a standby state, awaiting the next start command.

[0195] Microcontroller #1 senses the weight of the floor plate of the open elevator car (current load value) through four pads (piezoresistive sensors) under pedal 10. This weight, plus the inherent weight and resistance of the open elevator car and scissor lift platform, constitutes the actual mechanical load. A load detection circuit is constructed using piezoresistive sensors to measure the current load value. The signal from the load detection circuit is one of the input signals for both microcontrollers #1 and #2. A piezoresistive sensor inside the compressed air spring cylinder and a piezoresistive sensor at normal atmospheric pressure are connected to a differential bridge to construct a differential pressure detection circuit, detecting the difference between the air pressure inside the compressed air spring cylinder and normal atmospheric pressure. The signal from the differential pressure detection circuit is one of the input signals for microcontroller #1.

[0196] Microcontroller #1 uses a timer to generate a PWM signal, which is then used by a DC drive control circuit to control the speed of the DC motor and achieve soft start. Microcontroller #1 uses I / O3 and I / O4 ports to control the forward and reverse rotation of the DC motor. Microcontroller #1 uses I / O0 to send a control signal to cut off the power supply between the AC and DC motors.

[0197] Its load detection circuit is used to detect the load before the lifting stroke starts. Microcontroller #1 detects the load and obtains the current load value through this circuit. If the current load value exceeds the maximum load (the verified load), a control signal is sent via I / O0 to cut off the power supply to the AC and DC motors. I / O0 is restored to its initial value during the next microcontroller initialization process. Microcontroller #1 sets the fault status register to overload.

[0198] Microcontroller #1 and Microcontroller #2 work together during operation. Microcontroller #2's collaboration status register stores the current collaboration status value. Microcontroller #1 sends collaboration signals to Microcontroller #2. A level change on Microcontroller #1's IO7 pin triggers a level change on Microcontroller #2's EINT1 pin, causing an interrupt and entering the corresponding interrupt service routine. Microcontroller #2 reads the level status of Microcontroller #1's IO6 pin through IO2; a high level is "1", and a low level is "0". Microcontroller #2 also reads the level status of Microcontroller #1's IO5 pin through IO1; a high level is "1", and a low level is "0".

[0199] The load detection circuit is used to detect the load before the lifting stroke begins. Microcontroller #1 detects the load and obtains the current load value through this circuit. If the current load value exceeds twice the rated load but is less than the maximum load (i.e., the approved load), microcontroller #2 receives the coordination signal from microcontroller #1. During initialization, the motor power supply frequency parameter is set to Z0. (See...) Figure 40 The flowchart of the main program of microcontroller #2 is shown below.

[0200] If the current load is less than twice the rated load, before the #1 microcontroller sends the coordination signal to the #2 microcontroller, the frequency parameter of the motor power supply is set to Z1 during the initialization process. (See...) Figure 40 The flowchart of the main program of microcontroller #2 is shown below.

[0201] After the upward stroke begins, microcontroller #1 detects and performs relevant theoretical calculations through the load detection circuit to obtain the current actual mechanical load. If the load is lower than the load corresponding to the positive pressure convention value, i.e., the minimum preload force of the push rod, the differential pressure detection circuit checks whether the current pressure difference is lower than the positive pressure convention value. If it is, the DC motor is driven to rotate forward to increase pressure until the current pressure difference is not lower than the positive pressure convention value. Once the current pressure difference is detected to be not lower than the positive pressure convention value, the DC motor is immediately driven to rotate forward or started to rotate forward, causing IO5 to output a high level and IO6 to output a low level. The level change of IO7 triggers a level change of the EINT1 pin of microcontroller #2, sending a coordination signal to microcontroller #2. (See program flowchart). Figure 35 Microcontroller #2 enters the interrupt service routine, starts the AC motor to rotate forward, and uses the coordination status register to save the current coordination status between microcontroller #1 and microcontroller #2. The main program of microcontroller #1 continues to run. If it detects that the pressure difference between the cylinder pressure of the compressed air spring and the external atmospheric pressure has risen to the upper limit of positive pressure, it immediately calls the subroutine for driving the DC motor.

[0202] If the load exceeds the minimum preload force of the push rod corresponding to the positive pressure value, the DC motor will immediately be driven to rotate forward and apply pressure. When the pressure difference rises to the upper limit of the positive pressure, IO5 will output a high level, IO6 will output a low level, and the level change of IO7 will trigger a level change of the EINT1 pin of microcontroller #2, sending a coordination signal to microcontroller #2 and calling the subroutine for driving the DC motor (see program flowchart). Figure 35 Microcontroller #2 enters the interrupt service routine, starts the AC motor to rotate forward, and uses the coordination status register to save the current coordination status between microcontrollers #1 and #2. The upper limit of positive pressure corresponds to the maximum force of the DC electric push-pull rod. By outputting the maximum force through the DC electric push-pull rod, efforts are made to ensure that the AC motor can start under light load and avoid stalling.

[0203] After the descent stroke begins, microcontroller #1 detects whether the current differential pressure is higher than the negative pressure lower limit using a differential pressure detection circuit. If it is higher, it drives the DC motor to reverse until the current differential pressure is equal to or lower than the negative pressure lower limit. Once the current differential pressure is detected to be equal to or lower than the negative pressure lower limit, IO5 outputs a low level, IO6 outputs a high level, and the level change of IO7 triggers a level change on the EINT1 pin of microcontroller #2, sending a coordination signal to microcontroller #2 and calling the DC motor drive subroutine (see program flowchart). Figure 35 Microcontroller #2 enters the interrupt service routine, starts the AC motor to reverse, and uses the coordination status register to save the current coordination status between microcontroller #1 and microcontroller #2.

[0204] During the upward stroke, if the differential pressure detection circuit of microcontroller #1 detects that the differential pressure is lower than the maximum negative pressure, it will send a control signal to cut off the power supply to the AC motor and the DC motor via I / O0. I / O0 will be restored to its initial value during the next microcontroller initialization. Simultaneously, microcontroller #1 will immediately output a low level on I / O5 and I / O6. The level change on I / O7 will trigger a level change on the EINT1 pin of microcontroller #2. Microcontroller #2 will enter the interrupt service routine, setting the fault status register to a cooperative exception and clearing the cooperative flag. If a cooperative exception is subsequently detected, but the cooperative flag is cleared and the cooperative status register is set to its initial value of "000", it is considered that the cooperative exception fault has been resolved. If a cooperative exception is encountered again, the operation process remains the same: setting the fault status register to a cooperative exception and clearing the cooperative flag.

[0205] During the descent stroke, if the differential pressure detection circuit of microcontroller #1 detects that the differential pressure exceeds the agreed positive pressure value, it will send a control signal to cut off the power supply to the AC motor and DC motor via IO0. IO0 will be restored to its initial value during the next microcontroller initialization. Simultaneously, microcontroller #1 immediately sets IO5 and IO6 to low level, and the level change of IO7 triggers a level change on the EINT1 pin of microcontroller #2. Microcontroller #2 enters the interrupt service routine, sets the fault status register to a cooperative exception, and clears the cooperative flag. If a cooperative exception is subsequently detected, but the cooperative flag is cleared and the cooperative status register is set to its initial value of "000", it is considered that the cooperative exception fault has been resolved. If a cooperative exception is encountered again, the operation process is the same: the fault status register is set to a cooperative exception, and the cooperative flag is cleared.

[0206] Figure 32This is a schematic diagram of the collaborative status register of microcontroller #2. This register is related to the operation of the DC electric push-pull rod and the AC electric push-pull rod. Microcontroller #3 sets its own operating status register to "Run" and its stroke status to "Upward," and broadcasts the set values ​​of its own operating status register to the operating status registers of all microcontrollers. After receiving the relevant information from microcontroller #3, microcontroller #1 first sets its own operating status register to "Run" and its stroke status to "Upward." The collaborative status register of microcontroller #2 is related to the pressure difference between the cylinder pressure of the compressed air spring and the external atmospheric pressure. During product design, it is ensured that the pressure difference between the cylinder pressure of the compressed air spring and the external atmospheric pressure is maintained at a positive pressure predetermined value at the beginning of the upward stroke and the end of the downward stroke. At the beginning of the upward stroke, the pressure difference between the cylinder pressure of the compressed air spring and the external atmospheric pressure is the positive pressure predetermined value or slightly exceeds the positive pressure predetermined value. If it is lower than the positive pressure predetermined value, the DC motor rotates forward to increase the pressure until the condition is met. When microcontroller #1 detects that the actual load equals the load corresponding to the agreed positive pressure value, it continues to drive the DC motor to rotate forward or immediately starts the DC motor to rotate forward, and sends a coordination signal to microcontroller #2. Microcontroller #2 enters the corresponding interrupt service routine, sets the coordination flag to 1, reads the output value of microcontroller #1's IO6 port through IO2, and reads the output value of microcontroller #1's IO5 port through IO1. During the upward stroke, the motor rotates forward, the output value of microcontroller #1's IO6 port is low ("0"), and the corresponding bit in the coordination status register is "0"; the output value of microcontroller #1's IO5 port is high ("1"), and the corresponding bit in the coordination status register is "1". The status value of the coordination status register is "101", indicating that the DC motor is rotating forward. Clearing the coordination flag, the status value of the coordination status register is "001", indicating that the AC motor immediately starts rotating forward and maintains coordination with the DC motor. The main program of microcontroller #1 continues to run. If it detects that the pressure difference between the cylinder pressure of the compressed air spring and the external atmospheric pressure rises to the upper limit of the positive pressure, it immediately calls the subroutine for driving the DC motor.

[0207] This register is related to the operation of both DC and AC electric push-pull rods. Microcontroller #3 sets its own operating status register to "Run" and its stroke status to "Upward," broadcasting this setting to all other microcontrollers' operating status registers. Upon receiving information from Microcontroller #3, Microcontroller #1 first sets its own operating status register to "Run" and its stroke status to "Upward." Microcontroller #2's collaborative status register is related to the pressure difference between the cylinder pressure of the compressed air spring and the external atmospheric pressure. During product design, it is ensured that the pressure difference between the cylinder pressure of the compressed air spring and the external atmosphere remains at a predetermined positive pressure value at the beginning of the upward stroke and the end of the downward stroke. At the beginning of the upward stroke, the pressure difference between the cylinder pressure of the compressed air spring and the external atmospheric pressure is at or slightly exceeds the predetermined positive pressure value. Microcontroller #1 detects that the actual load exceeds the predetermined positive pressure value and immediately drives the DC motor to rotate forward and apply pressure. When the pressure difference rises to the upper limit of positive pressure, the DC motor is immediately driven to rotate forward and a coordination signal is sent to the No. 2 microcontroller. The subroutine for driving the DC motor is also called (see the program flowchart). Figure 35 The #2 microcontroller enters the corresponding interrupt service routine, sets the coordination flag to 1, and reads the output value of the #1 microcontroller's IO6 port through IO2 and the output value of the #1 microcontroller's IO5 port through IO1. During the upward stroke, the motor rotates forward, the output value of the #1 microcontroller's IO6 port is low ("0"), and the corresponding bit in the coordination status register is "0"; the output value of the #1 microcontroller's IO5 port is high ("1"), and the corresponding bit in the coordination status register is "1". The coordination status register value is "101", indicating that the DC motor is rotating forward. Clearing the coordination flag, the coordination status register value is "001", indicating that the AC motor immediately starts rotating forward and maintains coordination with the DC motor.

[0208] Microcontroller #3 sets its own running status register to "Run" and its stroke status to "Descending," and broadcasts this setting to the running status registers of all other microcontrollers. Upon receiving the information from microcontroller #3, microcontroller #1 first sets its own running status register to "Run" and its stroke status to "Descending." Then, while driving the DC motor in reverse, microcontroller #1 detects the pressure difference between the compressed air spring cylinder and the external atmospheric pressure. If microcontroller #1 detects that the differential pressure is equal to or lower than the negative pressure lower limit, it continues driving or immediately starts the DC motor in reverse, calls the DC motor drive subroutine, and simultaneously sends a coordination signal to microcontroller #2. Microcontroller #2 enters the corresponding interrupt service routine, sets the coordination flag to 1, reads the output value of microcontroller #1's IO6 port through IO2, and reads the output value of microcontroller #1's IO5 port through IO1. During the descent stroke, the motor reverses direction. The output of I / O6 on microcontroller #1 is high ("1"), and the corresponding bit in the coordination status register is also "1". The output of I / O5 on microcontroller #1 is low ("0"), and the corresponding bit in the coordination status register is "0". A coordination status register value of "110" indicates that the DC motor is reversing. Clearing the coordination flag results in a coordination status register value of "010", indicating that the AC motor immediately starts reversing, maintaining coordination with the DC motor.

[0209] During normal upward stroke operation, the pressure difference between the cylinder air pressure and the external atmospheric pressure of a gas spring should not fall below the lower negative pressure limit before reaching the end point. This is a requirement that the product must ultimately meet after design, debugging, and parameter tuning. Since the lower negative pressure limit is difficult to control, it is best to maintain positive pressure. If negative pressure occurs during operation, the pressure difference must be ensured not to fall below the lower negative pressure limit. Avoiding negative pressure during operation is mainly achieved by increasing the theoretical working stroke of the gas spring. If the cylinder air pressure does not exceed the lower negative pressure limit during the upward stroke, it is considered a coordination anomaly.

[0210] During normal descent, the pressure difference between the cylinder air pressure of the compressed air spring and the external atmospheric pressure should not exceed the agreed positive pressure value before reaching a specific distance L from the end point. This is the final requirement after the product has been designed, debugged, and its relevant parameters have been adjusted. The AC motor frequency parameter is set to Z2, which is a downward fluctuation of N2 to ensure the above requirements are met. It should be noted that during the descent stroke, the scissor lift platform should maintain a lag state. When the DC electric push-pull rod retracts to the end point, the distance from the end point of the scissor lift platform should be L or slightly greater than the specified distance L. The cylinder of the compressed air spring should be kept under negative pressure as much as possible. If positive pressure occurs during operation, the pressure difference must not exceed the agreed positive pressure value. There are two main methods to avoid positive pressure during operation: first, by increasing the theoretical working stroke of the compressed air spring; second, by setting the AC motor frequency parameter to a reasonable Z2 value. If the cylinder air pressure is not lower than the agreed positive pressure value during the descent stroke, it is considered a coordination anomaly.

[0211] During the product design process, it is required that no coordination anomalies occur under normal and fault-free operation of the AC drive system and DC drive system. However, coordination anomalies are allowed when the ascending and descending strokes are about to reach their ends. There are two ways to end the program: one is that the program ends naturally upon reaching the end point; the other is that the program ends due to a fault caused by the coordination anomaly. Taking the descending stroke as an example, these two program end methods are described. When the descending stroke is near its end, the DC electric push-pull rod has reached its position. The limit switch of the ordinary push-pull rod is triggered, the power is cut off, and it stops running. The AC electric push-pull rod pulls the scissor lift platform down, which in turn compresses, increasing the cylinder pressure of the compression air spring. Before the descending stroke reaches its end point, two situations may occur: First, the pressure difference between the cylinder pressure of the compression air spring and the external atmospheric pressure does not exceed the positive pressure convention value. When the #2 microcontroller detects that the scissor lift platform has descended to its end point, it ends the program; at this time, the pressure difference between the cylinder pressure of the compression air spring and the external atmospheric pressure is relatively close to the positive pressure convention value. In the second scenario, the pressure difference between the cylinder pressure of the compressed air spring and the external atmospheric pressure exceeds the agreed positive pressure value. Consequently, microcontroller #1 sends a coordination abnormality signal to microcontroller #2. At this time, the open elevator car is approaching its destination, and the program terminates due to the coordination abnormality causing a malfunction.

[0212] During the ascent process, if the differential pressure detection circuit of microcontroller #1 detects that the differential pressure exceeds the lower limit of negative pressure, it determines that the AC motor and DC motor cannot maintain coordination. During the descent process, if the differential pressure detection circuit of microcontroller #1 detects that the differential pressure exceeds the agreed positive pressure value, it also determines that the AC motor and DC motor cannot maintain coordination. The level change of the IO7 port of microcontroller #1 triggers the level change of the EINT1 pin of microcontroller #2, causing microcontroller #2 to enter the corresponding interrupt service routine and set the coordination flag to 1. The IO5 and IO6 ports of microcontroller #1 output a low level "0". Microcontroller #2 reads the corresponding level signal value through the IO1 and IO2 ports and sets the corresponding bit in the coordination status register to zero. Since both bits are zero, a coordination abnormality is determined, and the corresponding fault parameters are stored in the fault status register.

[0213] The value for a coordination anomaly is "100", where "1" represents the coordination flag. After clearing the coordination flag, the coordination status register returns to its initial value of "000". If a coordination anomaly is subsequently detected, but the coordination flag is cleared and the coordination status register returns to its initial value of "000", it indicates that the coordination anomaly fault has been resolved. A coordination anomaly is a fault warning, and its resolution relies on the self-checks of microcontrollers #1 and #2. If the self-checks of microcontrollers #1 and #2 do not detect a fault, then the coordination anomaly fault does not exist.

[0214] Figure 33 This is a schematic diagram of a microcontroller relay control circuit. This invention uses a relay device to isolate high-voltage and low-voltage circuits. A low-level signal at a certain I / O port of the microcontroller cuts off the transistor, resulting in no current in the relay coil. A high-level signal at another I / O port turns on the transistor, causing current in the relay coil and generating an electromagnetic induction magnetic field, which actuates the armature, closing the normally open contact and opening the normally closed contact. The delay contact, fixed to the piston rod, does not immediately actuate due to air damping within the piston, resulting in an action delay. Delay contacts can have either energization delay or de-energization delay. De-energization delay is a technique that delays the duration of power supply action; this invention does not employ this technique. This invention uses energization delay technology.

[0215] Figure 34 This diagram illustrates the circuit structure for controlling an AC contactor via the I / O0 output port of microcontroller #1. Microcontroller #3 is the master microcontroller, also known as the main control microcontroller; microcontrollers #1 and #2 are slave microcontrollers. Microcontroller #1 drives a DC motor, and microcontroller #2 drives an AC motor. The DC motor drive circuit is powered by a 24V DC power supply, and the AC motor drive circuit is powered by a 220V AC power supply.

[0216] A low-level signal at port IO0 cuts off the transistor, resulting in no current flowing through the relay coil. The three main contacts of the AC contactor are normally open. Two of the three main contacts are connected to the two ends of a 220V AC power supply; the other main contact is connected to one end of a 24V DC power supply. Because the main contacts are in their initial, normally open state, the 220V AC power supply cannot supply power to the AC motor drive circuit through the main contacts of the AC contactor; similarly, the 24V DC power supply cannot supply power to the DC motor drive circuit through the other main contact of the AC contactor.

[0217] Microcontroller #3 sets its own running status register to "Run" and its travel status to "Up" or "Down". Microcontroller #3 then broadcasts its own running status register value to all other microcontrollers' running status registers; this is the start command. Upon receiving the start command, microcontroller #1 first matches its running status register value with that of microcontroller #3. Next, microcontroller #1 uses a load detection circuit to obtain the current load value. If the actual load value exceeds the maximum load (the rated load), it sends a control signal to cut off the power supply to the AC and DC motors using I / O0. I / O0 is restored to its initial value during the next microcontroller initialization. Microcontroller #1 sets its fault status register to "Overload". If the load value does not exceed the maximum load (the rated load), I / O0 remains high, the transistor conducts, and current flows through the relay coil, attracting the armature. The three normally open main contacts of the AC contactor close. The 220V AC power supply supplies power to the AC motor drive circuit through the main contacts of the AC contactor; the 24V DC power supply supplies power to the DC motor drive circuit through the other main contact of the AC contactor.

[0218] Microcontroller #3 sets its own running status register to "Stop" (End), while maintaining its travel status unchanged. Microcontroller #3 then broadcasts its set running status register value to all other microcontrollers' running status registers; this is the "End Command." Upon receiving the End Command, Microcontroller #1 first aligns its running status register value with that of Microcontroller #3. Then, Microcontroller #1 outputs a low-level signal from its I / O0 port, cutting off the transistor and de-energizing the relay coil. The armature returns to its initial position under spring pressure, all normally open contacts of the AC contactor open, disconnecting the AC motor drive circuit from the AC power supply and the DC motor drive circuit from the DC power supply. Both the AC and DC motor drive circuits are now de-energized.

[0219] During the upward stroke, if the differential pressure detection circuit of microcontroller #1 detects that the differential pressure is lower than the negative pressure lower limit, it will send a low-level signal through port IO0 to cut off the transistor and de-energize the relay coil. The armature will return to its initial position under the action of the spring, all normally open contacts of the AC contactor will open, disconnecting the AC motor drive circuit from the AC power supply and the DC motor drive circuit from the DC power supply. Simultaneously, microcontroller #1 sends a coordination error signal to microcontroller #2 through port IO7. A change in the level of port IO7 of microcontroller #1 triggers a change in the level of pin EINT1 of microcontroller #2. Microcontroller #2 enters the interrupt service routine. The levels of ports IO5 and IO6 of microcontroller #1 are both low ("0"). Microcontroller #2 reads the levels of ports IO5 and IO6 through ports IO1 and IO2 respectively. The corresponding position in the coordination status register of microcontroller #2 is set to zero, indicating a coordination error.

[0220] During the descent stroke, if the differential pressure detection circuit of microcontroller #1 detects that the differential pressure exceeds the agreed positive pressure value, it will send a low-level signal through IO0 to cut off the transistor and de-energize the relay coil. The armature will return to its initial position under the action of the spring, all normally open contacts of the AC contactor will open, disconnecting the AC motor drive circuit from the AC power supply and the DC motor drive circuit from the DC power supply. Simultaneously, microcontroller #1 sends a coordination error signal to microcontroller #2 through its IO port. A change in the level of IO7 on microcontroller #1 triggers a change in the level of the EINT1 pin on microcontroller #2. Microcontroller #2 enters the interrupt service routine. The levels of IO5 and IO6 on microcontroller #1 are both low ("0"). Microcontroller #2 reads the levels of IO5 and IO6 through IO1 and IO2 respectively. The corresponding position in the coordination status register of microcontroller #2 is set to zero, indicating a coordination error.

[0221] Figure 35 The flowchart illustrates the execution of the DC motor drive subroutine, which is called during the execution of the main program of microcontroller #1. During the execution of the main program of microcontroller #1, the differential pressure detection circuit monitors the pressure difference between the cylinder pressure of the compressed air spring and the external atmospheric pressure. When the detected pressure difference approaches or reaches the upper limit of positive pressure or the lower limit of negative pressure, the main program will not stop the currently executing or about-to-be-executed program, but will promptly call the DC motor drive subroutine to implement relevant protection measures.

[0222] During the main program execution of microcontroller #1, a coordination signal is sent to microcontroller #2. After sending the coordination signal, this subroutine is executed. This subroutine is executed under the following two conditions: First, microcontroller #1 sends a coordination signal to microcontroller #2, its IO5 port outputs a high level, causing IO6 to output a low level, thus initiating forward motor rotation. Second, microcontroller #1 sends a coordination signal to microcontroller #2, its IO5 port outputs a low level, causing IO6 to output a high level, thus initiating reverse motor rotation. This subroutine terminates in two ways: First, the program terminates by checking the running status register; second, it checks for coordination anomalies, generates fault parameters, saves them to the fault status register, and exits the program. From a system design perspective, under normal operating conditions, the pressure difference between the cylinder pressure of the air spring and the external atmospheric pressure must be greater than the lower negative pressure limit before the upward stroke reaches its end. If the pressure difference is less than or equal to the lower negative pressure limit, a coordination anomaly occurs. From a system design perspective, under normal operating conditions, the pressure difference between the compressed air spring cylinder pressure and the external atmospheric pressure is less than the predetermined positive pressure value before the descent stroke reaches its end. If the pressure difference is greater than or equal to the predetermined positive pressure value, it indicates a coordination anomaly. The system design also ensures that before the system ascends and before the motor actuates, the initial pressure difference between the compressed air spring cylinder pressure and the external atmospheric pressure is close to or equal to the predetermined positive pressure value. At the end of the descent stroke, the pressure difference between the compressed air spring cylinder pressure and the external atmospheric pressure returns to the predetermined positive pressure value. Throughout the entire operation, the pressure difference between the compressed air spring cylinder pressure and the external atmospheric pressure varies within a certain range. This range is maintained between the upper limit of positive pressure and the lower limit of negative pressure. If this range is exceeded, the PWM signal duty cycle is zero, causing the DC motor to lose power.

[0223] Frequent hard starts during the rising and falling strokes can easily damage the DC motor; therefore, soft starts are used. During the rising stroke, the differential pressure is monitored. When the differential pressure is lower than the positive pressure balance value, PWM soft start is initiated. During the falling stroke, the differential pressure is monitored. When the differential pressure is higher than the negative pressure lower limit, PWM soft start is initiated.

[0224] Figure 35 This subroutine has an adaptive adjustment function, which effectively prevents excessive positive deviation between the DC electric push-pull rod stroke and the scissor lift platform stroke, and also effectively prevents the DC motor from being subjected to hard compression and hard dragging, thereby protecting the compressed air spring and DC motor.

[0225] The subroutine's termination is related to the existence of a positive pressure convention. During the product design process of this utility model, it was determined that at the start of the upward stroke of the open elevator car 7, when the DC drive motor begins to start, the pressure difference between the compressed air spring cylinder and the external atmospheric pressure is the positive pressure convention. Therefore, it is required that after the open elevator car 7 completes both the upward and downward strokes, the pressure difference between the compressed air spring cylinder and the external atmospheric pressure returns to the positive pressure convention. Due to the characteristics of the compressed air spring, there are errors such as hysteresis and repeatability, allowing a certain deviation between the actual pressure difference and the positive pressure convention. If the subroutine detects a negative actual pressure difference before the end of the upward stroke, it further checks; if the actual pressure difference is less than or equal to the lower limit of negative pressure, the subroutine returns in the form of a coordinated anomaly fault; otherwise, it waits for the host computer's termination instruction before returning. Before the end of the downward stroke, the subroutine continuously checks whether the actual pressure difference reaches or exceeds the positive pressure convention. Once it reaches or exceeds the positive pressure convention, the subroutine returns in the form of a coordinated anomaly fault; otherwise, it waits for the host computer's termination instruction before returning. The host computer, i.e., microcontroller #3, maintains communication with all microcontrollers, including microcontroller #2. Upon detecting a fault, it broadcasts a termination command, which is then stored in the operating status register of each microcontroller. Microcontroller #3 communicates with microcontroller #2 to obtain ultrasonic ranging results, thereby determining the position of the open-type elevator car. When the open-type elevator car reaches its travel end point, microcontroller #3 broadcasts a termination command, which is then stored in the operating status register of each microcontroller. During the execution of the DC motor drive subroutine, microcontroller #1 continuously checks the status register to see if it indicates termination; if so, the subroutine returns.

[0226] Regarding the definition and description of the agreed-upon value for positive pressure, a agreed-upon value is an indeterminate value; if it could be determined, it would not be called an agreed-upon value. Figure 30The characteristic curve of the gas spring shown illustrates the change in pressure difference (the difference between cylinder air pressure and external atmospheric pressure) with the extension stroke of the three-section DC electric push-pull rod. The curve exhibits a relatively long stroke where the pressure difference increases slowly with increasing stroke, showing an approximately linear relationship between stroke and pressure difference; this stroke is called the "theoretical working stroke." Conversely, there is a shorter stroke where the pressure difference increases relatively rapidly with increasing stroke, also showing an approximately linear relationship between stroke and pressure difference; this stroke is called the "high-pressure compression zone." The upper limit of the high-pressure compression zone is the upper limit of the positive pressure, and the lower limit of this linear zone is lower than the agreed-upon positive pressure value. Once the gas spring is designed and manufactured, the agreed-upon positive pressure value is essentially determined. This value is close to the lower limit of the high-pressure compression zone and higher than the air pressure difference value corresponding to the rated load, because the air pressure difference value corresponding to the rated load falls within the "theoretical working stroke." During the extension of the three-section DC electric push-pull rod, the compressed gas spring can only transmit the thrust of the three-section DC electric push-pull rod to the open elevator car if it remains compressed. The so-called "compression state" means that the pressure difference (the difference between the cylinder air pressure and the external atmospheric pressure) remains at a certain value, and these values ​​do not exceed the range of the "high-pressure compression zone". The positive pressure convention value is an objectively existing air pressure difference, which is the actual air pressure difference between the compressed gas spring cylinder pressure and the external atmospheric pressure before the electric push rod is activated. In terms of working principle, after activation, after one working cycle (the upward and downward strokes of the scissor lift platform), the actual air pressure difference between the compressed gas spring cylinder pressure and the external atmospheric pressure returns to the positive pressure convention value. Whether it can return to the positive pressure convention value depends on the pressure acting on the compressed gas spring during the descent of the scissor lift platform and the weight of the scissor lift platform and its load. Under no-load conditions, the weight of the scissor lift platform itself is limited, and the pressure needs to be increased to restore the compressed gas spring to its initial state. During descent, the pressure acting on the gas spring is generated by the conversion of the tension acting on the scissor lift platform. The pressure on the gas spring depends not only on the magnitude of the tension of the scissor lift platform but also on the initial value of the angle θ between the scissor arm and the horizontal line. When angle θ is zero, it is in a mechanical dead zone and cannot exert pressure on the gas spring. Only when angle θ is a specific value, i.e., the part of the elevator below ground level remains at a certain depth, can sufficient pressure be generated during the retraction of the AC electric push rod, acting together with the weight of the scissor lift platform, to act on the gas spring, allowing the gas spring cylinder pressure to return to its initial state when the elevator is unloaded. To ensure sufficient pressure, the tension of the AC electric push rod acting on the scissor lift platform is maximized, i.e., the output torque of the AC motor inside the AC electric push rod is maximized. The setting of the AC motor's operating power frequency parameter Z3 is related to the magnitude of the AC motor's output torque. The AC motor's operating power frequency parameter is the output frequency of the frequency converter. In vector control mode, the rule that a larger AC motor operating power frequency parameter setting results in a larger output torque is no longer followed.According to relevant technical data, Delta inverters, in vector control mode, can provide 200% of the starting torque when the heavy-load starting frequency is set to 0.5Hz. This means that under heavy load conditions, the inverter can provide sufficient torque at low frequencies to ensure equipment operation. Setting the operating power supply frequency parameter Z3 of the AC motor for the AC electric push-pull rod to a suitable value ensures the maximum output torque of the AC motor, but parameter Z3 cannot be set to zero. In short, the agreed-upon positive pressure value is primarily related to the inherent characteristic curve of the compressed air spring, secondly to the initial value of the angle θ between the scissor arm and the horizontal line, and also to the setting of the AC motor's operating power supply frequency Z3. In layman's terms: the agreed-upon value is a value with a certain degree of uncertainty, constrained by various factors (or agreed upon by multiple parties). It is obtained through repeated design and modification, continuous adjustment and testing until it meets the design requirements, ultimately becoming a real value. From a product design perspective, any periodic operating mechanism must ensure that after one or several cycles of operation, it returns to the starting point, i.e., the initial value. The air pressure value of the compressed air spring cylinder recovers to the pre-operation air pressure value after one cycle of operation in the system. The initial value of the difference between this air pressure value and atmospheric pressure is the positive pressure convention value.

[0227] Figure 35 This is a subroutine for executing the DC motor drive. This program involves the definition and description of the theoretical value of positive pressure balance. Balance refers to force equilibrium; according to Newton's first law, when the external force is zero (i.e., the thrust of the DC electric actuator equals its resistance), the actuator remains stationary or moves at a constant speed. The resistance of the DC electric actuator is the actual mechanical load described earlier. Assuming the compression spring cylinder can withstand infinite gas pressure, under the above conditions, its cylinder pressure value is the theoretical value of positive pressure balance. The calculation process is as follows: First, the pedal 10 has four pads, which are piezoresistive sensors used to measure the weight borne by the base plate of the open elevator car 7. During the assembly process of the scissor lift platform 13 and the open elevator car 7, the weight of each component is measured. The inherent frictional resistance of the scissor lift platform 13 during its ascent is calculated through the power consumption during the round trip under no-load conditions. The combined force of these three factors (the load-bearing capacity of the base plate, the inherent gravity of the scissor lift platform 13 and the open elevator car 7, and the inherent frictional resistance of the scissor lift platform 13 during its ascent) is tested or calculated using various methods. Second, the combined force of these three factors is divided by the cross-sectional area of ​​the cylinder gas passage to obtain a theoretical value, which is the theoretical value of positive pressure balance. The theoretical value of positive pressure balance varies with the load; under extremely high load conditions, this value may exceed the upper limit of positive pressure. During the ascent stroke, the pressure difference value (the difference between the cylinder pressure of the compressed air spring and atmospheric pressure) is monitored. When the pressure difference value is lower than the positive pressure balance value, PWM soft start is initiated. The above process is a purely theoretical process, which does not consider the effect of AC electric push-pull rods. The measurement of inherent frictional resistance is achieved through... Figure 9The power consumption of the dynamic physical model shown is measured, and then relevant calculations are performed.

[0228] According to the program settings, the differential pressure value is maintained between the upper limit of positive pressure and the lower limit of negative pressure. If this range is exceeded, the PWM signal duty cycle becomes zero, causing the DC motor to lose power. After the DC motor loses power, the air pressure value of the compressed air spring continues to be monitored. During the upward stroke, the elevator load is uncertain. The theoretical value of positive pressure balance varies with the load; under extremely high loads, this value may exceed the upper limit of positive pressure. According to the program settings, if the differential pressure value falls below the theoretical value of positive pressure balance after the DC motor loses power, it will restart. Therefore, under heavy elevator loads, the DC motor may experience repeated start-stop cycles. As previously explained, the DC electric push-pull rod uses a brushless DC servo motor (BLDC) with PWM soft start. This utility model design uses a brushless DC servo motor (BLDC) based on its ease of control and repeated soft start capabilities. When the differential pressure approaches the upper limit of the positive pressure, the PWM signal duty cycle is set to zero, thus protecting the DC motor drive circuit and preventing it from burning out due to excessive drive current. Simultaneously, the brushless DC servo motor (BLDC) executes PWM soft-start promptly after power failure to prevent the compressed air spring from losing its elasticity due to cylinder depressurization. The compressed air spring is an energy storage mechanism that stores the mechanical energy of the DC electric actuator, which is released during the advancement of the AC electric actuator. The AC electric actuator completes its advancement with the assistance of the compressed air spring's elasticity, overcoming the mechanical dead zone of the scissor lift mechanism.

[0229] Figure 36 for Figure 8 The diagram shows the distribution of components in the single-acting guide rail cylinder control system 14 and its surrounding area. The microcontroller shown in the diagram, and the microcontroller mentioned later, is either microcontroller #4 or microcontroller #5. Microcontroller #4 controls the opening and closing of the elevator door on the first floor; microcontroller #5 controls the opening and closing of the elevator door on the second floor. The core component of the single-acting guide rail cylinder control system 14 is a single-acting cylinder. Its internal spring has been removed, so it does not have an automatic recovery function and needs to rely on the gravity of the sliding door, i.e., elevator door 17, to recover.

[0230] Figure 36The elevator features the following main components: guide rails, single-acting cylinders, doors, windows, electromagnetic door catches and their peripheral circuits, pyroelectric infrared sensors, upper limit switches, lower limit switches, and electric bolt locks and their peripheral circuits. The main components are distributed as follows: two parallel guide rails are fixed to the outer sides of the elevator door and window openings on both sides. The windows are fixed above the door and window openings and cannot be moved; the doors move up and down along the guide rails, with long-stroke single-acting cylinders on the rails used to push the doors upwards. The doors and windows use new heat-insulating float glass, which blocks 90% of infrared light transmission, allowing visible light to enter the elevator car, which has no lighting system. The door frames are made of lightweight stainless steel. Upper and lower limit switches are installed above and below the guide rails to detect the door's open / closed status. An electric bolt lock and its peripheral circuits are located on one side below the door and window openings.

[0231] The electromagnetic door catcher and its peripheral circuitry are located above the window. When the door frame moves to the top and triggers the upper limit switch, the normally open contact 2 of the upper limit switch closes, energizing the electromagnetic door catcher's power supply circuit. The electromagnetic door catcher then generates a magnetic force to hold the lightweight stainless steel door frame in place. When the control signal from relay 2 causes the normally closed contact of relay 2 to open momentarily, the electromagnetic door catcher's power supply circuit is broken, resulting in a loss of power. The electromagnetic door catcher's magnetic force disappears, and the door moves downwards under gravity. The door frame shifts from its original position, the upper limit switch resets, and its normally open contact opens. Even if the normally closed contact of relay 2 closes again, the electromagnetic door catcher's power supply circuit remains open, the current is zero, and the electromagnetic door catcher generates no induced magnetic field.

[0232] Figure 36 The electric bolt lock employs a power-off unlocking design. The two fixed contacts of the electric bolt lock's power supply circuit are located on the frame below the door / window opening, while the two movable contacts are located on the lower edge of the door frame and move with it. The initial state is characterized by the two fixed contacts and two movable contacts being in close contact, closing the power supply circuit and energizing the elevator door. When the control signal from relay 1 causes the normally closed momentary contact of relay 1 to open, the power supply circuit is disconnected, and the elevator door unlocks after power loss.

[0233] The elevator door has an automatic return-to-initial-state function. When the elevator door is in the offset initial position, the power supply circuit of the electric bolt lock is disconnected because the two fixed contacts and the two moving contacts are separated. The electric bolt lock is in a power-off unlocked state. Under the action of gravity, it moves down along the guide rail. At the moment when the lower edge of the elevator door frame makes close contact with the frame below the door and window opening, the two fixed contacts and the two moving contacts of the electric bolt lock power supply circuit make close contact again. The electric bolt lock power supply circuit is re-established, the electric bolt lock is energized, and the elevator door automatically locks, returning to the initial state.

[0234] Figure 36There are two relay components. Relay 1 is a time-delay relay, and relay 2 is a regular relay without a time-delay function. Adjust the time delay of relay 1 so that it is exactly the time required for the electric bolt lock to open after power failure.

[0235] Figure 37 The diagram shows the distribution of components related to the intake control of a single-acting cylinder. The sub-control microcontroller shown in the diagram, and the sub-control microcontrollers mentioned later, are either microcontroller #4 or #5. Microcontroller #4 controls the opening and closing of the elevator door on the first floor; microcontroller #5 controls the opening and closing of the elevator door on the second floor. The main control microcontroller shown in the diagram is microcontroller #3.

[0236] Because the single-acting cylinder eliminates the need for a spring, the thrust is increased. The functions and roles of each component are described below: Figure 17 The electromagnetic door catcher is essentially a coil; when its power supply circuit is closed and energized, it generates a magnetic force. Figure 17 The middle door frame is made of iron, which makes it susceptible to electromagnetic attraction. Figure 17 The Zhongdian bolt lock adopts a power-off unlocking design; once its power supply circuit is disconnected, it will immediately lose power and unlock. Figure 17 The normally closed pilot-operated two-position three-way valve is used to change the passage of the cylinder, that is, to control the cylinder to be connected to the air source or the outside. When its control terminal is not energized, it is in the normally closed state, that is, the cylinder is connected to the outside but not to the air source. When its control terminal is energized, it is in the open state, that is, the cylinder is connected to the air source but not to the outside. Figure 17 The intermediate relay 1 is a time-delay relay with instantaneous and delayed contacts. It sends instantaneous and delayed control signals simultaneously. The instantaneous control signal controls the power supply circuit of the electric bolt lock to be de-energized, and the delayed control signal controls the control terminal of the pilot-operated two-position three-way valve to be energized. The delay time is exactly the time required for the electric bolt lock to de-energize and unlock.

[0237] The electric bolt lock shown in the diagram must be de-energized and unlocked before the single-acting cylinder receives air. The relay simultaneously sends two control signals: an instantaneous control signal that instantly triggers the electric bolt lock to de-energize and unlock, and a delayed control signal that, after a certain delay, energizes the control coil of the normally closed pilot-operated two-position three-way valve, connecting the single-acting cylinder to the air source and executing the air intake operation.

[0238] Figure 37 The main control microcontroller shown is microcontroller #3, and the sub-controllers are either microcontroller #4 or microcontroller #5. Microcontroller #4 controls the opening and closing of the elevator door on the first floor; microcontroller #5 controls the opening and closing of the elevator door on the second floor.

[0239] The single-acting cylinder's air intake process is implemented as follows: The main control microcontroller sends an opening interruption request signal to the sub-control microcontroller. The sub-control microcontroller's interrupt response control relay 1 simultaneously sends an instantaneous control signal and a delayed control signal. The instantaneous control signal de-energizes the electric bolt lock, causing it to unlock. The delayed control signal delays for a period of time, which is the time required for the electric bolt lock to unlock. After the delay, the control coil of the normally closed pilot-operated two-position three-way valve is energized, causing the valve to operate. This connects the air source to the cylinder, allowing air to enter. The single-acting cylinder pushes the iron door frame upward. The iron door frame touches the upper limit switch, closing the normally open contact 2, directly forming the power supply circuit for the electromagnetic door catcher. The electromagnetic door catcher, energized, generates a magnetic field that attracts the iron door frame.

[0240] Figure 38 The diagram shows the component distribution for the exhaust control of a single-acting cylinder. The main control microcontroller's I / O port is connected to the external interrupt pin EINT1 of the sub-control microcontroller. The sub-control microcontroller shown in the diagram, and the sub-control microcontrollers mentioned later, are either microcontroller #4 or microcontroller #5. Microcontroller #4 controls the opening and closing of the elevator door on the first floor; microcontroller #5 controls the opening and closing of the elevator door on the second floor. The main control microcontroller shown in the diagram is microcontroller #3.

[0241] Figure 38 The main control microcontroller's I / O port is connected to the external interrupt pin EINT1 of the sub-control microcontroller. The main control microcontroller uses the edge generated by the output level change of the I / O port to trigger an external interrupt in the sub-control microcontroller. The sub-control microcontroller performs a door-closing operation during the interrupt service routine. The door-closing process is accompanied by the exhaust process of the single-acting cylinder.

[0242] The diagram shows the connection between the main control microcontroller's I / O ports and the sub-controller's I / O ports. The connection process between ordinary I / O ports is as follows: The main control microcontroller uses its I / O port output to connect with the sub-controller's I / O port input, directly feeding back the elevator car's position status to the sub-controller via the I / O ports. The main control microcontroller continuously detects the elevator car's position using an ultrasonic ranging sensor, feeding back relevant status information to the sub-controller via the corresponding I / O ports. The initial state of the I / O ports is high level "1". A high level "1" indicates the following situations: no detection, the elevator car not stopped at the correct position, not stopped, or not stopped at the floor controlled by the sub-controller. When the sub-controller on one floor detects that the main control microcontroller's I / O port output is low level "0", it means that the main control microcontroller has detected that the elevator car is stopped on the first floor and its position is correct. When the second-floor sub-control microcontroller detects that the main control microcontroller's I / O port output is in a low-level "0" state, it indicates that the main control microcontroller has detected that the elevator car has stopped on the second floor and its position is correct.

[0243] Since the single-acting cylinder removes the spring, the exhaust needs to be achieved with the help of the elevator door's gravity. The implementation process is as follows: The sub-control microcontroller cyclically detects whether the following three situations occur: (1) the main control microcontroller sends a door closing interruption request signal; (2) the sub-control microcontroller detects that the door closing request button, i.e., button D, is pressed; (3) when the sub-control microcontroller detects that the elevator car position status signal is low level "0", and at the same time, the pyroelectric sensor detects that the car is unoccupied. Once the sub-control microcontroller detects the above situations, it uses IO to output a low level signal to relay 1, the relay 1 coil is de-energized, and returns to the initial state; the control signal is sent through relay 2 and kept waiting for a certain period of time, so that the normally closed contact of relay 2 remains open for a short time, the electromagnetic door suction power supply circuit is de-energized, causing the electromagnetic door suction coil to be de-energized, losing the effect of magnetic force, the elevator door gravity acts on the cylinder, the cylinder exhausts the air and moves down, the door frame shifts from its original position, the upper limit switch returns to the initial state, and the upper limit switch normally open contact 2 is opened. Even if the normally closed contact of relay 2 closes again, the power supply circuit is still disconnected. The electromagnetic door loses its current and has no induced magnetic field. Due to the use of lightweight materials, the elevator door's weight is limited; furthermore, due to air damping, the elevator door moves slowly downwards. Under the weight of the elevator door, the gas in the cylinder is expelled. The gas in the cylinder is released to the outside through a two-position three-way valve, and the elevator door eventually returns to its initial position.

[0244] Figure 39 The diagram shows the main component connections of the core part of the elevator intelligent detection and control system, utilizing the serial port 0 of the microcontroller to build a multi-machine communication system. Microcontroller #3 is the master microcontroller, and it communicates with peripheral microcontrollers in two ways: one is via a 485 bus, and the other is via I / O ports. In the 485 bus communication system with microcontroller #3 as the master, microcontroller #3 is also called the master microcontroller, while microcontrollers #1, #2, #4, and #5 are all slaves. Microcontroller #4 primarily uses I / O communication with microcontroller #3, supplemented by serial communication. Microcontroller #5 primarily uses I / O communication with microcontroller #3, supplemented by serial communication. Microcontroller #1 and #2 use unidirectional I / O communication, i.e., microcontroller #1 sends a coordination signal to microcontroller #2. Microcontroller #2, as a slave, uses serial port 0 as the communication interface to communicate with the host microcontroller #3 via the 485 bus. Microcontroller #2 serves as the control host for the Delta frequency converter. It uses serial port 1 as its communication interface, converting the signal to 485 level using a MAX485 chip to achieve one-to-one communication with the Delta frequency converter. Microcontroller #2 indirectly controls the AC motor of the AC electric push-pull rod through the Delta frequency converter. Microcontroller #1 directly controls the DC motor of the DC electric push-pull rod. Microcontroller #4 is the sub-control microcontroller for the first-floor elevator door, and microcontroller #5 is the sub-control microcontroller for the second-floor elevator door. Microcontrollers #4 and #5 are also referred to simply as the sub-control microcontrollers.

[0245] Figure 39The diagram shows the main component connections of the intelligent detection and control core of the elevator, with each microcontroller having a clearly defined function. Microcontroller #4 controls the opening and closing of the elevator doors on the first floor; microcontroller #5 controls the opening and closing of the elevator doors on the second floor; microcontrollers #1 and #2 control the elevator car's lifting and lowering drive system and have automatic fault detection capabilities; microcontroller #2 continuously detects the elevator car's position and position changes using an ultrasonic sensor; microcontroller #3 is the main control microcontroller, communicating with microcontroller #2 to obtain real-time information about the elevator car's position changes, i.e., its lifting and lowering status, which is displayed via indicator lights. When the elevator car reaches a floor, the main control microcontroller notifies the corresponding floor's microcontroller via a low-level I / O port. The microcontrollers control the opening and closing of the elevator doors and detect their opening and closing status using upper and lower limit switches. Once the elevator door closes, the sub-control microcontroller promptly sends the door closure status information back to the main control microcontroller, which then displays the information via indicator lights.

[0246] The hardware and software are designed in a collaborative manner. The main control microcontroller program follows these rules: all elevator doors must be closed during elevator car operation, and pressing any button during elevator operation is ineffective. The main control microcontroller obtains the opening and closing status of the elevator doors through feedback from the sub-control microcontrollers. The main control microcontroller can only drive the electric push-pull lever to perform elevator car operation after the two sub-control microcontrollers have completed the door closing operation. While the electric push-pull lever is being driven by microcontrollers #1 and #2, the main control microcontroller no longer detects the status changes of buttons A, B, and C through the I / O port. Instead, it continuously polls the operating status of microcontrollers #1 and #2, obtains ultrasonic ranging results by maintaining communication with microcontroller #2, and then continuously detects the position of the elevator car.

[0247] Communication between the main control microcontroller and the sub-control microcontrollers is crucial for their collaborative operation. Communication between the main control microcontroller and the sub-control microcontrollers revolves around three scenarios: First, a door closing request signal and feedback; second, elevator car position information; and third, a door opening interruption request signal. In the main control microcontroller's program design, two flags are set corresponding to the first and second floors. Before executing the elevator car lifting / lowering operation, the flags are set to "1," indicating that it is currently unclear whether the elevator doors on the first and second floors are closed. The main control microcontroller's program continuously checks whether all flags are cleared. Only when all flags are cleared does the main control microcontroller issue a start command, and only then do microcontrollers #1 and #2 execute the elevator car lifting / lowering operation. Elevator car lifting / lowering must be performed with both the first-floor and second-floor elevator doors closed.

[0248] Two-way communication is achieved using external interrupts to implement the main control microcontroller's door closing request signal and the sub-control microcontrollers' door closing status feedback. During the main program design of the main control microcontroller, two flag bits are set corresponding to the first and second floors. These flag bits are set to "1" before the elevator car's ascent / descend operation. The main control microcontroller uses an edge generated by an I / O level change to trigger the external interrupt EINT1 of the sub-control microcontrollers on the first and second floors. The sub-control microcontrollers enter their external interrupt service routines, perform the door closing operation, and obtain information about whether the elevator door is closed by checking the status of the lower limit switch. If closure is not detected, the sub-control microcontroller continues to obtain information about whether the elevator door is closed by checking the lower limit switch and repeats the door closing operation until the elevator door is closed. After obtaining the door closing status information for the first floor, the sub-control microcontroller on the first floor triggers the main control microcontroller's external interrupt EINT0 using an edge generated by an I / O level change, causing the main control microcontroller to enter its external interrupt service routine, and the flag bit corresponding to the first floor is cleared. After the second-floor sub-control microcontroller obtains the door closing status information of the elevator on the second floor, it uses the edge generated by the I / O level change to trigger the external interrupt EINT1 of the main control microcontroller, causing the main control microcontroller to enter the external interrupt service routine, and the flag bit corresponding to the second floor is cleared.

[0249] In the second scenario of communication between microcontrollers, the master microcontroller communicates directly with the sub-controller via I / O ports, feeding back elevator car position information. The master microcontroller sets its I / O port output level high to indicate one of four scenarios: 1. The car is not currently moving; 2. The car is not currently stopped at the correct position; 3. The car is not currently stopped at the floor controlled by the sub-controller; 4. The master microcontroller has not detected the elevator car's position. Setting the master microcontroller's I / O port output level low indicates that the car is currently stopped at the floor controlled by the sub-controller and at the correct position. Upon detecting a low-level signal via the I / O port, the sub-controller immediately checks the pyroelectric signal. If no one is detected in the car, it executes the door closing operation.

[0250] In the third scenario of communication between microcontrollers, the master microcontroller sends a door-opening interrupt request signal to the sub-controller. The door-opening interrupt signal is triggered by an edge generated by a change in the output level of a certain I / O port of the master microcontroller, causing an external interrupt in the sub-controller. The relevant interrupt program in the sub-controller executes the operation to control the elevator door opening, accompanied by the air intake process of the single-acting cylinder. The scenarios in which the master microcontroller sends a door-opening interrupt request signal to the sub-controller on the first floor are as follows: First scenario: The elevator car descends from the second floor to the first floor, the descent is complete, the electric push-pull rod motor stops, and the master microcontroller sends a door-opening interrupt request signal to the sub-controller on the first floor; Second scenario: The elevator car stops at the first floor, the call button on the outside of the first floor is pressed, and the master microcontroller sends a door-opening interrupt request signal to the sub-controller on the first floor; Third scenario: The elevator car stops at the first floor, the door-open button on the inside of the first floor is pressed, and the master microcontroller sends a door-opening interrupt request signal to the sub-controller on the first floor. The main control microcontroller sends an open door interruption request signal to the second-floor sub-control microcontroller in the following scenarios: First, when the elevator car rises from the first floor to the second floor, the ascent is complete, the electric push-pull rod motor stops, and the main control microcontroller sends an open door interruption request signal to the second-floor sub-control microcontroller. Second, when the elevator car stops at the second floor, and the call button on the outside of the second floor is pressed, the main control microcontroller sends an open door interruption request signal to the second-floor sub-control microcontroller. Third, when the elevator car stops at the second floor, and the door open button on the inside of the second floor is pressed, the main control microcontroller sends an open door interruption request signal to the second-floor sub-control microcontroller.

[0251] The core of the elevator intelligent detection and control system is essentially a distributed control system in a master-slave mode. The master microcontroller is microcontroller #3. Three buttons are directly connected to microcontroller #3: the call button, the door open request button, and the ascend (or descend) request button. Microcontroller #3 coordinates the opening and closing of the elevator doors and the raising and lowering of the elevator car. The opening and closing of the elevator doors on the first floor is controlled by microcontroller #4, and the opening and closing of the elevator doors on the second floor is controlled by microcontroller #5. Microcontroller #2 indirectly controls the AC electric push-pull rod through a Delta frequency converter. The Delta frequency converter directly controls the extension and retraction of the AC electric push-pull rod, thereby controlling the raising and lowering of the scissor lift platform. Microcontroller #2 obtains the position of the open elevator car 7 through an ultrasonic ranging circuit and saves the result to the relevant registers. Microcontroller #3 maintains communication with microcontroller #2 to obtain the specific location of the open elevator car 7. Microcontroller #1 directly controls the DC electric push rod and coordinates the extension and retraction of the DC and AC electric push rods. In the 485 bus communication system, microcontroller #3 is the master microcontroller, and the other microcontrollers are slaves. Microcontroller #3 issues commands and polls the status of the other microcontrollers through the 485 bus communication system. However, in addition to bus communication, there is also I / O port communication. Communication between microcontroller #3 and microcontroller #4 mainly uses I / O port communication. Communication between microcontroller #3 and microcontroller #4 is mainly bidirectional communication using I / O ports, with bus communication as an auxiliary method. Communication between microcontroller #3 and microcontroller #5 is mainly bidirectional communication using I / O ports, with bus communication as an auxiliary method. In principle, the two slaves (lower-level machines) communicate indirectly through the master, but in this design, microcontroller #1 and microcontroller #2 communicate directly and unidirectionally through I / O ports, sending coordination signals; microcontroller #1 sends information, and microcontroller #2 receives information.

[0252] Figure 40This is the flowchart of the main program for microcontroller #2, which uses a branching design. Microcontroller #2 is the master microcontroller and the slave of microcontroller #3. The program checks the running status register to determine whether it's an ascending or descending stroke. If it's a descending stroke, the descending stroke-related program is executed. If it's an ascending stroke, microcontroller #2 uses the load detection circuit to obtain the current load value. If the current load value exceeds the maximum load (the rated load), microcontroller #2 sets the fault status register to overload and stops operation; otherwise, it executes the ascending stroke-related program. Ultrasonic ranging is initiated to determine if the car position is correct. During the ascending stroke, the car is at the bottom; during the descending stroke, it's at the top. A certain degree of deviation is allowed when determining the car position. If the position is incorrect, the machine needs to be stopped for maintenance. Incorrect car position can be caused by various reasons, such as mechanical system failure. If the position is correct, inverter fault detection is initiated. If there is no fault signal from the inverter, the operating power frequency of the AC motor of the AC electric push-pull rod is set, and the ascending stroke is set to the parameter setting value Z1 or Z0. Before the upward stroke begins, the execution program initializes, setting the AC motor's operating power frequency based on the current load value. If the current load value is less than twice the rated load, the AC motor's operating power frequency is set to Z1; otherwise, it is set to Z0. During program initialization, the value N0 is set to the number of loop iterations the program waits for, variable N is assigned a value of zero, and the fault status register is restored to its initial value. The program executes a loop, waiting for the correct coordination signal from microcontroller #1. If variable N > N0, meaning that microcontroller #1 does not send a signal or does not send a correct coordination signal within the waiting time, the DC motor drive system malfunctions, and microcontroller #2 sets the value of the fault status register to DC motor fault and stops operation. If microcontroller #1 sends a correct coordination signal, the AC motor starts.

[0253] During AC motor operation, continuous fault detection and ultrasonic ranging are performed. Three types of faults may occur during operation: first, a coordinated abnormality fault; second, a frequency converter fault signal; and third, a stalled rotor. For the first type of fault, the system design rationally designs the theoretical working stroke of the compressed air spring; during debugging, the AC motor's operating power frequency parameters are rationally adjusted to ensure that this fault avoids occurrence during operation under normal conditions, allowing it to occur only at the end of the stroke or beyond. During the descent stroke, the AC motor's operating power frequency parameter Z2 is crucial for avoiding coordinated abnormality faults during operation. As previously discussed, coordinated abnormality is a fault warning, and its troubleshooting relies on the self-checks of microcontrollers #1 and #2. If the self-checks of microcontrollers #1 and #2 do not detect a fault, then the coordinated abnormality fault does not exist. After design, debugging, and relevant parameter adjustments, the product ensures that the first type of coordinated abnormality fault can only occur at the end of the stroke or beyond the stroke under normal operation. For the second type of fault, only shutdown and repair are possible. The second type of fault detection is achieved through the frequency converter's self-check function. The second type of fault requires shutdown and repair. The third type of fault is caused by overloading and is prone to occur during the startup phase.

[0254] During the AC motor startup phase, two scenarios can occur under overload conditions. Scenario 1: Before starting, the DC motor, due to overload, outputs maximum force and then loses power to prevent excessive current from burning out the circuit. Due to the self-locking function of the DC electric push-pull rod, the pressure of the compressed air spring cylinder is maintained at the upper positive pressure limit, and the scissor lift platform receives maximum force. The AC electric push-pull rod initially acts on the scissor lift platform; if pushed, the pressure of the compressed air spring cylinder decreases. When it decreases to a certain value, the DC motor soft-starts, and the DC electric push-pull rod moves together with the AC electric push-pull rod. Scenario 2: Before starting, the DC motor, due to overload, outputs maximum force and then loses power to prevent excessive current from burning out the circuit. Due to the self-locking function of the DC electric push-pull rod, the pressure of the compressed air spring cylinder is maintained at the upper positive pressure limit, and the scissor lift platform receives maximum force. The AC electric push-pull lever initially applied to the scissor lift platform but was difficult to move. Ultrasonic ranging was activated, and it was found that the scissor lift platform's position had not changed significantly. An alarm was triggered, the coordination flag was cleared, fault parameters were generated and stored in the fault status register, and operation ceased. The #3 microcontroller, acting as the host computer, issued a termination command via broadcast upon receiving relevant fault information.

[0255] During the descent, ultrasonic ranging and fault detection are continuously activated to continuously determine whether the distance to the endpoint is less than a specific distance L. When the distance to the endpoint is less than the specific distance L, the AC motor stops for 10 seconds. Then, it is re-initialized, changing the operating power frequency of the AC motor of the AC electric push-pull rod from Z2 to Z3, and the AC motor is started in reverse.

[0256] The program includes settings for the AC motor's operating power frequency. During the upward stroke, the AC motor's operating power frequency is set to Z1 or Z0, and during the downward stroke, it is set to Z2. When the distance to the endpoint is less than a specific distance L, the AC motor stops for 10 seconds, and the operating power frequency is changed from Z2 to Z3. The AC motor's operating power frequency setting to Z3 is related to the positive pressure convention. The Delta inverter uses the IM FOCPG control mode, i.e., closed-loop current vector control mode. In this mode, even if the AC motor frequency parameter setting value Z3 is close to zero, the AC motor still has a large torque output. The AC motor frequency parameter is set in the range of (0, 10), and the Z3 value is set to maximize the pulling force of the AC electric push-pull rod. A lower AC motor frequency parameter results in slower speed and higher output torque.

[0257] The program includes setting the operating power frequency of the AC motor. Setting the AC motor's operating power frequency to the Z3 value maximizes the output pulling force of the AC electric push-pull rod. This value is related to the final determination of the positive pressure constraint value. Essentially, the positive pressure constraint value is related to the spring design. Once the spring is designed and manufactured, its characteristic curve is determined, and thus the positive pressure constraint value is determined. The positive pressure constraint value is thus initially determined. The positive pressure constraint value cannot be lower than the lower limit of the high-pressure compression zone, and the positive pressure constraint value corresponds to a load that is exactly equal to the resultant force of the external forces. One of the resultant forces is the AC electric push-pull rod's pulling force acting on the scissor lift platform, which is converted into pressure and acts on the compressed gas spring at the end of its descent stroke; the other resultant force is the minimum weight of the scissor lift platform and its auxiliary mechanisms. The lower limit of the θ angle is thus initially determined. By adjusting the AC motor frequency parameters, the AC electric push-pull rod outputs maximum pulling force. After the pulling force is converted into pressure by the scissor lift platform, the lower limit of the θ angle is further fine-tuned. As long as the design angle θ is greater than its lower limit, at the end of the descent stroke, the AC electric push-pull rod overcomes the elastic force of the compressed gas spring and pulls the scissor lift platform back to its initial position of the ascending stroke.

[0258] During program initialization and before program termination, fault detection is performed to promptly detect whether there are any faults in the motor and their states. If a fault is found, fault parameters are generated and saved to the fault status register, and then the program terminates. Not only does the main program of microcontroller #2 perform fault self-checks during program initialization and before program termination, but the main programs of other microcontrollers must also perform fault self-checks during program initialization and before program termination. Microcontroller #3 performs fault self-checks during program initialization and before program termination. As the host computer, microcontroller #3 must maintain communication with all other microcontrollers, promptly detect and save fault information from each microcontroller during operation, and issue termination commands and alarms. At program termination, microcontroller #3, as the host computer, must poll the fault status registers of each microcontroller, save the relevant fault information, and upon the next startup, poll the fault self-check status of each microcontroller to update the fault status information promptly.

[0259] Figure 41 The source shown is Figure 36 The circuit shown is a schematic diagram of the peripheral circuit structure of the limit switch and electromagnetic door catcher. This utility model uses a limit switch device to detect the opening and closing status of the elevator door. The specific structure of the limit switch detection circuit is as follows: one end of the normally open contact of the limit switch is connected to the 5V power supply of the microcontroller, and the other end is connected to the microcontroller's I / O port. A 10K pull-down resistor is connected to the microcontroller's I / O port to form the limit switch detection circuit. The closing of the upper limit switch contact indicates that the door is open, and the closing of the lower limit switch contact indicates that the door is closed. A low potential at node f in the upper limit switch circuit indicates that the elevator door is not open, and a high potential at node f in the upper limit switch circuit indicates that the elevator door is open; a low potential at node h in the lower limit switch circuit indicates that the elevator door is not closed, and a high potential at node h in the lower limit switch circuit indicates that the elevator door is closed. This utility model uses electromagnetic door catcher technology, with sufficient power, and the generated electromagnetic attraction force is much greater than the weight of the sliding door, i.e., the elevator door itself. The electromagnetic door suction coil power supply circuit consists of the electromagnetic door suction coil, the normally open contact 2 of the upper limit switch, a 24V DC power supply, and the normally closed contact of relay 2 connected in series.

[0260] Figure 42 The circuit shown originates from Figure 36 The circuit shown illustrates the initial state of the electromagnetic door catch release process. The diagram shows the microcontroller acting on the electromagnetic door catch circuit via a relay. The microcontroller controls relay 2 through its I / O port, causing the normally closed contact of relay 2 to open, disconnecting the power supply to the electromagnetic door catch coil. The electromagnetic door catch loses power, the elevator door loses its electromagnetic force, and the elevator door begins to descend under gravity.

[0261] Figure 43 The circuit shown originates from Figure 36The circuit shown illustrates the subsequent states of the electromagnetic door release process. After the normally closed contact of relay 2 opens, the electromagnetic door release is de-energized, releasing the elevator door. Under gravity, the elevator door descends, causing both normally open contacts 1 and 2 of the upper limit switch to open. Even if the normally closed contact of relay 2 closes, the power supply circuit for the electromagnetic door release coil remains disconnected. The elevator door, losing its electromagnetic force, continues to descend under gravity, performing the closing operation.

[0262] Figure 44 This is a simplified structural diagram of a normally closed pilot-operated two-position three-way valve, which includes two states: one is the energized state, and the other is the de-energized state.

[0263] Figure 45 This is a normally closed, pilot-operated, two-position, three-way valve control circuit, with the working port connected to the exhaust port. The single-acting cylinder communicates with the outside environment through the exhaust port of this valve. The delay contact shown in the diagram is not closed, which could be due to two scenarios: first, the relevant relay has not activated; second, the relay has activated, but the delay time has not elapsed, hence the delay contact is not closed.

[0264] Figure 46 This is a normally closed, pilot-operated, two-position, three-way valve control circuit. The valve is energized and activated when the delayed contact closes, connecting the working port to the air source inlet. The air source passes through this valve and connects to a single-acting cylinder, actuating the cylinder piston.

[0265] Figure 47 The circuit shown originates from Figure 36 The circuit shown illustrates the operation of an electric bolt lock. The elevator door in the diagram is descending but has not yet reached the bottom. The power supply circuit for the electric bolt lock is open, and moving contacts I and J are fixed to the lower side of the metal frame of the moving elevator door. The electric bolt lock is de-energized; however, it employs a power-off unlocking design, therefore it is in the unlocked state.

[0266] Figure 48 The circuit shown originates from Figure 36 The circuit shown illustrates the operation of an electric bolt lock. In the diagram, the electric bolt lock's power supply circuit is open. The elevator door falls freely under gravity, with moving contact I in close contact with fixed contact X, and moving contact J in close contact with fixed contact Y. The electric bolt lock's power supply circuit is closed, and the electric bolt lock is energized. Since the electric bolt lock uses an energized locking design, it is in the locked state.

[0267] Figure 49 The circuit shown originates from Figure 36 The circuit shown illustrates the operation of an electric bolt lock. When the power supply circuit of the electric bolt lock changes from a continuous state to an open state, the normally closed momentary contact of relay 1 actuates, the power supply circuit of the electric bolt lock changes from a continuous state to an open state, the electric bolt lock changes from a energized state to a de-energized state, and the electric bolt lock unlocks.

[0268] Figure 50 This invention relates to an elevator door opening control circuit that employs a power-on delay technique. The circuit state is shown before the preset time. Before the elevator door can open, the electric bolt lock must be unlocked. Due to the lag in mechanical action, a delay is required. This invention combines power-on delay technology with a single-acting cylinder to push the elevator door upwards, thus opening the door. The single-acting cylinder is connected to the outside environment or an air source via a normally closed pilot-operated two-position three-way valve. The normally open delay contact of relay 1 is connected to the control circuit of the normally closed pilot-operated two-position three-way valve. The normally closed instantaneous contact of relay 1 is connected to the power supply circuit of the electric bolt lock. Before relay 1 is activated, the single-acting cylinder is connected to the outside environment through the exhaust port of the normally closed pilot-operated two-position three-way valve. The microcontroller activates relay 1 through a certain I / O port. The normally closed instantaneous contact of relay 1 actuates, the power supply circuit of the electric bolt lock changes from a continuous state to an open state, the electric bolt lock changes from an energized state to a de-energized state, and the electric bolt lock unlocks. It should be noted that the preset time of the normally open delay contact of relay 1 is longer than the unlocking time of the electric bolt lock.

[0269] Figure 51 The elevator door opening control circuit employs a power-on delay technique, and the diagram shows the circuit state after a preset time. The microcontroller activates relay 1 via a specific I / O port. Related actuators perform a series of operations to open the elevator door: First, the normally closed instantaneous contact of relay 1 opens, disconnecting the power supply circuit to the electric bolt lock, causing it to unlock. Due to the lag in mechanical action, a delay time needs to be set to ensure the electric bolt lock completes the unlocking operation. After the preset time, the electric bolt lock completes the unlocking operation, the normally open delayed contact of relay 1 closes, the normally closed pilot-operated two-position three-way valve is energized, the single-acting cylinder is connected to the air source, and the elevator door is pushed upwards to open.

[0270] Figure 52 for Figure 39 The diagram illustrates the hardware circuit interface for elevator door opening and closing control. The microcontroller uses two I / O ports to send control signals and two other I / O ports to receive feedback signals. The microcontroller receives external commands and information and executes elevator door opening and closing operations accordingly: It energizes relay 1 and de-energizes relay 2 via relevant I / O ports, triggering related circuits and actuators to perform the door opening operation; it also energizes relay 2 and de-energizes relay 1 via relevant I / O ports, triggering related circuits and actuators to perform the door closing operation; the upper limit switch and its circuit detect the elevator door's open state and provide feedback to the microcontroller's relevant I / O ports, and the lower limit switch and its circuit detect the elevator door's closed state and provide feedback to the microcontroller's relevant I / O ports; the control and feedback loops together form a closed-loop control system.

[0271] Figure 53The diagram illustrates the copper infiltration technology for Al2O3 ceramics. Before firing, Al2O3 powder is evenly distributed, and a certain amount of copper powder is infiltrated into specific areas (indicated by the black dots), which are then pressed into circular end faces. After firing, the copper powder melts and infiltrates into the gaps between the Al2O3 ceramic particles, making the areas indicated by the black dots conductive.

[0272] Figure 54 The image shows two views of an AL2O3 ceramic dome. Piezoresistive strain gauges are attached to the end face of the ceramic dome, and the lead wires are attached to the copper-impregnated area.

[0273] Figure 55 The diagram shows the cylinder piston structure of the compressed air spring. The detection circuit is fixed inside the piston rod, which is a hollow rod. The signal line of the detection circuit is shown as a dashed line and is connected to the copper-impregnated area on the back of the AL2O3 ceramic round cover.

[0274] Figure 56 The diagram shows a temperature compensation circuit. A thermistor is connected in series to compensate for the deviation of the piezoresistive strain gauge caused by temperature changes. If the piezoresistive strain gauge has a positive temperature coefficient, the thermistor connected in series has a negative temperature coefficient; if the piezoresistive strain gauge has a negative temperature coefficient, the thermistor connected in series has a positive temperature coefficient.

[0275] In summary, the elevator operation in this invention is divided into two scenarios: the ascending stroke and the descending stroke. During the ascending stroke, the travel of the three-section DC electric push-pull rod exceeds the travel of the lifting platform, or during the descending stroke, the travel of the lifting platform exceeds the travel of the three-section DC electric push-pull rod. In this case, the compressed gas spring will be excessively compressed, causing a rapid increase in air pressure within its cylinder. When the extension stroke of the three-section DC electric push-pull rod during the ascending stroke is less than the travel of the lifting platform, or during the descending stroke, the travel of the lifting platform is less than the retraction stroke of the three-section DC electric push-pull rod, the compressed gas spring adaptively compensates for the stroke deviation through deformation. However, the deformation of the compressed gas spring is limited; when dragging occurs, negative pressure is generated in the compressed gas spring cylinder. The compressed gas spring has relatively low tensile strength, thus preventing excessive dragging.

[0276] A differential pressure detection circuit is constructed by combining the piezoresistive sensor of the compressed air spring with a piezoresistive sensor that senses the external atmospheric pressure. This differential pressure detection circuit, along with the load detection circuit, forms the core sensing element of the drive control system.

[0277] Using microcontroller #1 as the core of the adaptive control system, we designed related adaptive control and protection software and hardware to achieve the coordinated operation between the DC drive system controlled by microcontroller #1 and the AC drive system controlled by microcontroller #2.

[0278] Since the actual system contains multiple driving components, the coordination between AC driving components and DC driving components relies on the adaptiveness of related components and the adaptive design of related control systems.

[0279] The compressed gas spring serves as both a buffer and an energy storage component. As a buffer, it prevents hard collisions or dragging between the AC and DC drive components. As an energy storage component, it converts and stores the mechanical energy of the three-section DC electric push-pull rod into elastic potential energy, which is then adaptively released through the rotation of the lead screw of the AC electric push-pull rod.

[0280] The above description discloses only one or more preferred embodiments of the present utility model, and should not be construed as limiting the scope of the present utility model. Those skilled in the art can understand that implementing all or part of the above embodiments and making equivalent changes in accordance with the claims of the present utility model are still within the scope of the utility model.

Claims

1. A playground elevator equipped with an HDPE curved slide, characterized in that, It includes a curved slide and a small two-story elevator with short vertical lift. The elevator's second-floor exit connects to the curved slide's entrance. The curved slide's exit is located near the elevator's first-floor entrance. The curved slide is made of HDPE material, the slide base and support are made of stainless steel, the slide is assembled with the stainless steel frame by buckles, and a stainless steel guardrail is installed at the entrance of the curved slide. The elevator adopts a structure combining a scissor lift platform and an AC electric push-pull rod. The horizontal extension and retraction of the push-pull rod drives the vertical lifting of the scissor lift platform, and the braking is achieved by relying on the mechanical self-locking characteristic of the screw. The elevator adopts an open elevator car. The floor of the open elevator car is equipped with a step. Four piezoresistive sensors are placed at the four corners of the step where they contact the floor. The load detection circuit is constructed using the piezoresistive sensors to sense the load-bearing capacity of the floor of the open elevator car. Parallel tracks are arranged on both sides of the elevator shaft door opening to allow the elevator door to move up and down along the tracks. The open-type elevator car is symmetrically equipped with compressed air springs of the same specification and model on both sides as buffer components and energy storage components. Below them are three-section DC electric push-pull rods of the same specification and model. The ends of the three-section DC electric push-pull rods are mechanically connected to the ends of the compressed air springs. The three-section DC electric push-pull rods help the open-type elevator car to rise. A piezoresistive sensor is installed inside the cylinder of the compressed air spring. A differential pressure detection circuit is constructed by using the built-in piezoresistive sensor of the compressed air spring cylinder and an external piezoresistive sensor that senses the external atmospheric pressure.

2. The amusement elevator equipped with an HDPE curved slide as described in claim 1, characterized in that, The follower of the scissor lift platform and the lead screw and slider of the AC electric push-pull rod are integrated and slide with the rotation of the lead screw.

3. The amusement elevator equipped with an HDPE curved slide as described in claim 1, characterized in that, The compressed gas spring serves as both a buffer component and an energy storage component; The compressed air spring serves as a buffer component to prevent the three-section DC electric push-pull rod from acting directly on the open elevator car, thereby preventing hard collisions or dragging between the AC drive component and the DC drive component. The compressed gas spring, as an energy storage component, works in conjunction with the three-section DC electric push-pull rod to convert electrical energy into mechanical energy, and then convert the mechanical energy into elastic potential energy and store it. The release of the elastic potential energy is adaptively controlled by the rotation of the lead screw of the AC electric push-pull rod.

4. The amusement elevator equipped with an HDPE curved slide as described in claim 1, characterized in that, DC electric push-pull rods use a direct control method, while AC electric push-pull rods use an indirect control method. The DC drive motor for the DC electric linear actuator is a brushless DC motor, directly controlled by PWM speed regulation; the AC drive motor for the AC electric linear actuator is indirectly controlled by a VFD-MH300 frequency converter.

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