A pressure-regulated energy-storaged release linear push rod

Abstract

The present application relates to a kind of pressure-regulated energy-storing release linear push rod, including electromagnetic brake mechanism, ball spline linear motion mechanism, energy storage device, the ball spline linear motion mechanism front connection energy storage device, rear connection electromagnetic brake mechanism, through the cooperation of ball spline linear motion mechanism and electromagnetic brake mechanism, realize energy storage-release mode, or non-energy storage-release mode.Compared with the prior art, the present application uses adjustable pneumatic device to store energy, compared with the structure of mechanical device, it is also simple, and has the characteristics of adjustable energy storage.The application object of the present application is also different, and the precision of operation can be ensured to a large extent during movement.Using the present application in robot system, effective energy storage control based on overall servo system can be formed.

Description

Technical Field

[0001] This invention relates to a linear actuator, and more particularly to a linear actuator for energy storage and release. Background Technology

[0002] Based on existing robotics technology, especially biomimetic robotics, the performance parameters such as speed and force of motion are affected by the structure, control components, and signal transmission functions, especially for power components that transmit power at a constant speed and with equal force.

[0003] Based on research into biomimetic robots, the power components for biomimetic human muscles include pneumatic muscles, servo motors, and rotary motors. These components can simulate the movement of human muscles to some extent. However, human muscles can perform complex movements such as variable force movements and instantaneous force exertion, which cannot be achieved by simple electronic control components.

[0004] This paper provides a detailed analysis of the movement characteristics of human muscles. Human muscles can be abstracted as a subactuated, multi-degree-of-freedom system, exhibiting unique and complex movement characteristics such as elastic cushioning, explosive movement, and small-force movement. They can also form compound explosive movements based on specific joints and specific muscles.

[0005] Based on previous inventions and research, biomimetic approaches to muscle systems fall into two main categories: motor-driven and fluid-driven. The main achievement of fluid-driven systems is pneumatic muscles; motor-driven systems primarily utilize servo motors. These two drive systems have their own characteristics. Fluid-driven systems exhibit slow movement speeds and low precision, but offer a wide range of motion, high adjustability, and the ability to transmit extremely large forces. Motor-driven systems can achieve extremely high speeds and higher precision, but are limited to specific force and speed ranges. When achieving extremely high instantaneous acceleration, inertia can damage the electronic control system. Furthermore, both systems are constrained by the control system during high-speed movements. After analyzing these functional shortcomings, and following the innovative design process outlined in "Modern Mechanical Design Methods," these shortcomings were set as the goals of the innovative design.

[0006] In summary, to better simulate the explosive movement of human muscles, we identified functional deficiencies in the muscle systems of modern bionic robots and implemented innovative designs.

[0007] Design a human muscle-inspired dynamic system that combines the characteristics of two control systems. This system should possess the high force transmission capability of a fluid-driven system and the precise control capability of an electronic control system.

[0008] Patent publication number "WO2022188463A1" discloses an "OIL-ELECTRICITY HYBRID INJECTIONMOLDING MACHINE", i.e., an "oil-electric hybrid injection molding machine", such as... Figure 1 As shown, the device includes a base, a loading cylinder, a lead screw, and a power system. The power system includes a motor, an injection unit, a feeding unit, and a hydraulic auxiliary unit. The injection unit includes an injection power assembly, an injection transmission assembly, and a first clutch. The feeding unit includes a feeding power assembly, a feeding transmission assembly, and a second clutch, with the first and second clutches spaced apart on the output shaft. The hydraulic auxiliary unit includes an auxiliary cylinder and an energy accumulator. During injection, the energy accumulator releases energy, and the rodless chamber of the auxiliary cylinder is filled with oil. In this invention, the coaxial arrangement of two clutches allows injection and feeding to share a single motor, reducing the required motor specifications. Furthermore, by using the auxiliary cylinder, especially during injection, the injection pressure, speed, and accuracy under hybrid power are ensured. During backward loosening and backpressure actions, high-precision screw movement can be achieved by controlling the hydraulic pressure.

[0009] Because the hydraulic-electric hybrid injection molding machine uses a complex screw and power system structure, and can only be used in injection molding machines, a voltage-regulating, energy-storing and releasing device is needed to adapt it to a robot system and form an effective energy storage control based on an overall servo system. Summary of the Invention

[0010] Based on the above background technology, the present invention proposes a pressure-regulating linear actuator with energy storage and release. This linear actuator has the power transmission of a fluid drive system, and can simulate the explosive force of human muscles through energy storage and release. At the same time, it meets the function of a high-precision linear actuator and can realize high-precision, high-speed motion based on servo electronic control.

[0011] To achieve the above objectives, the technical solution of the present invention is: a voltage-adjustable linear actuator capable of storing and releasing energy, comprising an electromagnetic braking mechanism, a ball spline linear motion mechanism, and an energy storage device. The ball spline linear motion mechanism is connected to the energy storage device at the front and to the electromagnetic braking mechanism at the rear. Through the coordinated operation of the ball spline linear motion mechanism and the electromagnetic braking mechanism, an energy storage-release mode or a non-energy storage-release mode can be achieved.

[0012] Furthermore, the ball spline linear motion mechanism includes front and rear fixed ends, a ball spline nut, a linear bearing, a ball spline screw, a buffer spring, a guide shaft, a piston head, and a servo motor. The front fixed end serves as a support for the front end of the ball spline screw. The front end of the ball spline screw is connected to the servo motor via a diaphragm coupling 1, and the rear end is fixedly connected to the right fixed end. The right fixed end is connected to the piston head via a floating joint. The front fixed end is connected to the front cover of the sleeve containing the energy storage device via multiple guide shafts and a linear bearing. The front end of the guide shaft is fixed to the front fixed end, and the rear end passes through the linear bearing fixed to the front cover of the sleeve. A buffer spring is sleeved between the rear end face of the linear bearing and the stop nut at the rear end of the guide shaft. The ball spline nut is installed on the ball spline screw between the front fixed end and the front cover of the sleeve.

[0013] Furthermore, an urethane anti-collision block is sleeved on the rear end of the ball spline screw.

[0014] Furthermore, the ball spline screw is provided with a spline guide groove. When no torque is applied to the ball spline screw, the ball spline nut can reciprocate linearly along the spline guide groove on the ball spline screw; when torque is applied to the ball spline screw, the ball spline nut will move helically along the helical groove on the screw, that is, the rotation is converted into a precise linear motion of a specific length.

[0015] Furthermore, the electromagnetic braking mechanism is installed on the front cover of the sleeve and the guide shaft, and includes a locking tube, a snap ring, a locking sleeve, an electromagnetic shaft, a insert-type electromagnetic coil, and a cantilever pin. The locking sleeve is sleeved on the guide shaft through the locking tube, and the locking sleeve is placed inside the front cover of the sleeve. It is connected to the insert-type electromagnetic coil through the electromagnetic shaft. The insert-type electromagnetic coil is installed on the insert-type electromagnetic coil mounting ring, and the insert-type electromagnetic coil mounting ring is connected to the external bracket through the cantilever pin.

[0016] Furthermore, when the insert-type electromagnetic coil is energized in the positive direction, it pulls the electromagnetic shaft to move. The electromagnetic shaft drives the locking sleeve to move, and under the action of the wedge surface, the slotted locking tube hugs the guide shaft, thus achieving the braking effect.

[0017] Furthermore, when the insert-type electromagnetic coil is energized in the reverse direction, it drives the electromagnetic shaft to move in the reverse direction. At this time, the locking sleeve will move in the reverse direction, and under the action of the wedge surface, it will loosen the guide shaft, thus achieving the effect of brake release.

[0018] Furthermore, the energy storage device includes an air bladder, an air bladder interface, an external interface, a rear cover, and quick connectors. The air bladder is placed in a sealed chamber at the front of the sleeve. The front end of the air bladder is connected to the external interface installed in the rear cover of the sleeve through the air bladder interface, and two quick connectors are installed on the external interface.

[0019] Furthermore, the sealed chamber is divided into two sealed parts by an air storage bladder, with the outer cavity outside the air storage bladder and the inner cavity inside the air storage bladder.

[0020] Furthermore, the pressure in the outer cavity and the pressure in the inner cavity constitute the energy stored in the energy storage device; the pipeline connecting the inner cavity to the outside is equipped with a one-way valve, a reversing solenoid valve, a digital barometer, and a servo variable pump system, which are used to change the pressure of the energy storage device by increasing or decreasing the air pressure in the inner cavity.

[0021] The beneficial effects of this invention are:

[0022] This invention, in its design process, follows the innovative design flow in "Modern Mechanical Design Methods," identifying functional shortcomings from the kinematic characteristics of the muscle systems in modern humanoid robots. Then, based on the innovative design methods in "Modern Mechanical Design Methods," it employs the "heterogeneous object combination method" within the solid element combination innovation approach, combining a pneumatic energy storage device for fluid power with an electrically powered control motor to compensate for their respective shortcomings. This innovative design conforms to current mechanical design principles. 。

[0023] Compared to existing technologies, this invention uses an adjustable pneumatic device for energy storage, which is simpler in structure than mechanical devices and also features adjustable energy storage. This invention is also applicable to different objects, ensuring greater operational accuracy during movement.

[0024] Applying this invention to robot systems can create effective energy storage control based on an overall servo system.

[0025] This invention is a linear actuator with energy storage and release function, which combines the advantages of fluid drive and electronic control drive. It can be used as a drive system for biomimetic muscle tissue and can simulate the explosive force of human muscles.

[0026] The energy storage device of the present invention is an adjustable energy storage-release system. Through a servo pneumatic system, it can realize the combined energy storage and release of multiple push rods. It can also accurately calculate energy, adjust it and then release it. Compared with general energy storage systems, it is more compatible and intelligent.

[0027] The electromagnetic braking mechanism in this invention is a wedge-shaped braking mechanism that acts on the moving pair, while the motor's holding brake is a braking mechanism that acts on the rotating pair. In comparison, this invention is a new solution that can be used as a braking module in vertically placed axial protection, and has a wide range of applications. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of an existing hybrid injection molding machine.

[0029] Figure 2This is a layout diagram of the three parts of the linear push rod of the present invention;

[0030] Figure 3 This is a cross-sectional view of the linear push rod structure of the present invention;

[0031] Figure 4 This is a three-dimensional schematic diagram of the internal structure of the linear push rod of the present invention;

[0032] Figure 5 Schematic diagram of a ball spline linear motion mechanism;

[0033] Figure 6 This is a magnified view of a ball spline linear motion mechanism.

[0034] Figure 7 A three-dimensional schematic diagram of the electromagnetic brake mechanism;

[0035] Figure 8 This is a cross-sectional view of the electromagnetic braking mechanism.

[0036] Figure 9 This is a partial enlarged view of the electromagnetic brake mechanism structure;

[0037] Figure 10 This is a cross-sectional view of the energy storage device structure;

[0038] Figure 11 for Figure 10 Top sectional view;

[0039] In the diagram: 1-Electromagnetic brake mechanism, 2-Ball spline linear motion mechanism, 3-Energy storage device, 1.1-Locking tube, 1.2-Snap ring, 1.3-Locking sleeve, 1.4-Electromagnetic shaft, 1.5-Plug-in electromagnetic coil, 1.6-Cantilever pin, 1.7-Guide shaft, 2.1-Front fixed end, 2.2-Ball spline nut, 2.3-Linear bearing, 2.4-Ball spline screw, 2.5-Buffer spring, 2.6-Guide shaft, 2.7-Uri-rubber anti-collision block, 2.8-Floating joint, 2.9-Piston head, 2.10-Right fixed end, 2.11-Diaphragm coupling, 2.12-Servo motor, 3.1-Air reservoir, 3.2-Air reservoir interface, 3.3-External interface, 3.4-Rear cover, 3.5-Quick connector A, 3.6-Quick connector B, 3.7-Sealing O-ring. Detailed Implementation

[0040] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0041] like Figures 2 to 4As shown, the present invention mainly consists of three parts: an electromagnetic braking mechanism 1, a ball spline linear motion mechanism 2, and an energy storage device 3. The ball spline linear motion mechanism 2 is connected to the energy storage device 3 at the front and to the electromagnetic braking mechanism 1 at the rear. Through the coordinated operation of the ball spline linear motion mechanism 2 and the electromagnetic braking mechanism 1, an energy storage-release mode or a non-energy storage-release mode can be realized.

[0042] The motion process of the three parts—electromagnetic brake mechanism 1 and ball spline linear motion mechanism 2—is as follows: This linear push rod is mainly moved by the ball spline linear motion mechanism. During the motion, energy is stored in the energy storage device, and the stored energy can be released through the electromagnetic brake mechanism. The amount of stored energy can be changed by pressurizing or depressurizing the air storage bladder through an externally connected pneumatic system to alter the energy release.

[0043] This pusher has two modes: energy storage-release mode and non-energy storage-release mode.

[0044] I. The three parts of the energy storage-release mode work together as follows:

[0045] (1) The electromagnetic brake mechanism is released;

[0046] (2) The servo motor drives the ball spline motion;

[0047] (3) The electromagnetic brake mechanism stops after reaching the point;

[0048] (4) The energy storage device has stored energy during the movement;

[0049] (5) The external pressure regulating system adjusts the internal pressure of the air storage bladder and adjusts the stored air pressure energy;

[0050] (6) The electromagnetic brake mechanism is released, and the stored energy is released.

[0051] II. The three parts of the non-energy storage-release mode work together as follows:

[0052] (1) The electromagnetic brake mechanism is released;

[0053] (2) The servo motor drives the ball spline motion;

[0054] (3) The electromagnetic brake mechanism stops after reaching the point;

[0055] (4) The energy storage device is constantly depressurized during the movement;

[0056] The structure of each part is described in detail below.

[0057] (1) Ball spline linear motion mechanism

[0058] The structure of a ball spline linear motion mechanism is as follows: Figure 5As shown in Figure 6, it includes a front fixed end 2.1, a ball spline nut 2.2, a linear bearing 2.3, a ball spline screw 2.4, a buffer spring 2.5, a guide shaft 2.6, a urethane anti-collision block 2.7, a floating joint 2.8, a piston head 2.9, a right fixed end 2.10, a diaphragm coupling 2.11, and a servo motor 2.12.

[0059] The front fixed end 2.1 serves as the front support for the ball spline screw 2.4. The front end of the ball spline screw 2.4 is connected to the servo motor 2.12 via a diaphragm coupling 2.11, and the rear end is fixedly connected to the right fixed end 2.10. The right fixed end 2.10 is connected to the piston head 2.9 via a floating joint 2.8. The front fixed end 2.1 is connected to the front cover of the sleeve containing the energy storage device 3 via multiple guide shafts 2.6 and a linear bearing 2. The front end of the guide shaft 2.6 is fixed to the front fixed end 2.1, and the rear end passes through the linear bearing 2 fixed to the front cover of the sleeve. A buffer spring 2.5 is sleeved between the rear end face of the linear bearing 2 and the stop nut at the rear end of the guide shaft 2.6. A ball spline nut 2.2 is installed on the ball spline screw 2.4 between the front fixed end 2.1 and the front cover of the sleeve. A urethane anti-collision block 2.7 is sleeved on the rear end of the ball spline screw 2.4.

[0060] Like a ball screw module, the ball spline linear motion mechanism adds reciprocating motion to the rotary motion. When no torque is applied to the screw, the ball spline nut can reciprocate linearly along the spline guide groove on the screw. When torque is applied to the screw, the ball spline nut moves helically along the helical groove on the screw, thus converting rotation into precise linear motion of a specific length.

[0061] This feature allows the entire assembly to reciprocate even when the ball spline screw is not rotating, thus achieving the function of a jacking screw pair.

[0062] (2) Electromagnetic braking mechanism

[0063] The electromagnetic braking mechanism is the innovation of this invention. Due to the characteristics of the ball spline helical pair, when there is no torque input, the helical pair will be blocked, leaving only the moving pair. Therefore, the braking mechanism is needed to restrict the moving pair to prevent the energy storage device from releasing too early.

[0064] An electromagnetic brake mechanism is a type of brake mechanism that acts on a moving pair. Its main principle is wedge motion, which causes the bushing to bite the guide shaft, thereby increasing friction and achieving the braking effect.

[0065] The electromagnetic brake mechanism is mounted on the front end of the movable sleeve and on the guide shaft 2.6, such as... Figure 7As shown in Figures 8 and 9, the device includes a locking tube 1.1, a snap ring 1.2, a locking sleeve 1.3, an electromagnetic shaft 1.4, a insert-type electromagnetic coil 1.5, and a cantilever pin 1.6.

[0066] The locking sleeve 1.3 is fitted onto the guide shaft 2.6 through the locking tube 1.1, and the locking sleeve 1.3 is placed inside the front cover of the sleeve. It is connected to the insert type electromagnetic coil 1.5 through the electromagnetic shaft 1.4. The insert type electromagnetic coil 1.5 is installed on the insert type electromagnetic coil mounting ring, and the insert type electromagnetic coil mounting ring is connected to the external bracket through the cantilever pin 1.6.

[0067] The relative movements of this electromagnetic brake mechanism are as follows: The cantilever pin serves to fix the mounting ring of the insert-type electromagnetic coil to the external bracket. When the insert-type electromagnetic coil is energized in the positive direction, it will pull the electromagnetic shaft to move. The electromagnetic shaft will drive the locking sleeve to move. Under the action of the wedge surface, the slotted locking tube will hug the guide shaft to achieve the braking effect.

[0068] When the insert-type electromagnetic coil is energized in the reverse direction, it will drive the electromagnetic shaft to move in the reverse direction. At this time, the locking sleeve will move in the reverse direction, and under the action of the wedge surface, it will release the guide shaft, thus achieving the effect of brake release.

[0069] (3) Energy storage device

[0070] The energy storage device is the innovation of this invention. The function of the energy storage device is to store the pressure changes caused by the spatial changes in the rear half of the linear push rod, thereby achieving the function of energy storage.

[0071] The structure of energy storage devices, such as Figure 10 As shown in Figure 11, the device includes an air reservoir 3.1, an air reservoir interface 3.2, an external interface 3.3, a rear cover 3.4, quick connector A 3.5, quick connector B 3.6, and a sealing O-ring 3.7. The air reservoir 3.1 is placed in the outer cavity of the front part of the sleeve. The front end of the air reservoir 3.1 is connected to the external interface 3.3 installed in the rear cover 3.4 of the sleeve through the air reservoir interface 3.2, and quick connectors A 3.5 and B 3.6 are installed on the external interface 3.3.

[0072] The energy storage device is housed in a sealed chamber, divided into two sealed parts by a gas storage bladder. The area outside the gas storage bladder is defined as the outer cavity, and the area inside is defined as the inner cavity. During movement, the overall volume of the cavity decreases, the outer cavity is pressurized, and this pressure acts on the inner cavity, thus pressurizing the gas inside.

[0073] The pressure in the outer cavity and the pressure in the inner cavity together constitute the energy stored in the energy storage device at this time. Since the inner cavity is connected to the outside, pressure control components such as check valves, reversing solenoid valves, digital barometers, and servo variable pump systems are installed on the pipeline connected to the outside to change the pressure of the energy storage device by increasing or decreasing the pressure in the inner cavity.

[0074] When increased energy storage is needed, the inner cavity can be pressurized; when decreased energy storage is needed, the inner cavity can be depressurized. An electromagnetic braking device is required during the release and energy storage process of the push rod.

Claims

1. A voltage-adjustable linear actuator capable of storing and releasing energy, characterized in that: The system includes an electromagnetic braking mechanism, a ball spline linear motion mechanism, and an energy storage device. The ball spline linear motion mechanism is connected to the energy storage device at the front and to the electromagnetic braking mechanism at the rear. Through the coordinated operation of the ball spline linear motion mechanism and the electromagnetic braking mechanism, an energy storage-release mode or a non-energy storage-release mode can be achieved. The ball spline linear motion mechanism includes a front fixed end, a rear fixed end, a ball spline nut, a linear bearing, a ball spline screw, a buffer spring, a guide shaft, a piston head, and a servo motor. The front fixed end serves as a support for the front end of the ball spline screw, which is connected to the servo motor via a diaphragm coupling. The rear end is fixedly connected to the right fixed end, which is connected to the piston head via a floating joint. The front fixed end is connected to the front cover of the sleeve housing the energy storage device via multiple guide shafts and linear bearings. The front end of the guide shaft is fixed to the front fixed end, and the rear end passes through the front cover of the sleeve. A linear bearing is provided, with a buffer spring fitted between the rear end face of the linear bearing and the stop nut at the rear end of the guide shaft; a ball spline nut is installed on the ball spline screw between the front fixed end and the front cover of the sleeve; the electromagnetic brake mechanism is installed on the front cover of the sleeve and the guide shaft, including a locking tube, a snap ring, a locking sleeve, an electromagnetic shaft, a insert-type electromagnetic coil, and a cantilever pin. The locking sleeve is fitted onto the guide shaft through the locking tube and is placed inside the front cover of the sleeve. It is connected to the insert-type electromagnetic coil through the electromagnetic shaft. The insert-type electromagnetic coil is installed on the insert-type electromagnetic coil mounting ring, which is connected to the external bracket through the cantilever pin; the energy storage device includes an air bladder, an air bladder interface, an external interface, a rear cover, and quick connectors. The air bladder is placed in a sealed chamber at the front of the sleeve. The front end of the air bladder is connected to the external interface installed in the rear cover of the sleeve through the air bladder interface, and two quick connectors are installed on the external interface.

2. The adjustable-voltage linear actuator with energy storage and release capability according to claim 1, characterized in that: An urethane anti-collision block is sleeved on the rear end of the ball spline screw.

3. The adjustable-voltage linear actuator with energy storage and release capability according to claim 1, characterized in that: The ball spline screw is provided with a spline guide groove. When no torque is applied to the ball spline screw, the ball spline nut can reciprocate linearly along the spline guide groove on the ball spline screw. When torque is applied to the ball spline screw, the ball spline nut will move helically along the helical groove on the screw, that is, the rotation is converted into linear motion.

4. The adjustable-voltage linear actuator with energy storage and release capability according to claim 1, characterized in that: When the insert-type electromagnetic coil is energized in the positive direction, it pulls the electromagnetic shaft to move. The electromagnetic shaft drives the locking sleeve to move. Under the action of the wedge surface, the slotted locking tube hugs the guide shaft, achieving the braking effect.

5. The adjustable-voltage linear actuator with energy storage and release capability according to claim 1, characterized in that: When the insert-type electromagnetic coil is energized in the reverse direction, it drives the electromagnetic shaft to move in the reverse direction. At this time, the locking sleeve will move in the reverse direction, and under the action of the wedge surface, it will loosen the guide shaft, thus achieving the effect of brake release.

6. The adjustable-voltage linear actuator with energy storage and release capability according to claim 1, characterized in that: The sealed chamber is divided into two sealed parts by an air storage bladder, with the outer cavity outside the air storage bladder and the inner cavity inside the air storage bladder.

7. The adjustable-voltage, energy-storing and releasing linear actuator according to claim 6, characterized in that: The pressure in the outer cavity and the pressure in the inner cavity together constitute the energy stored in the energy storage device. The pipeline connecting the inner cavity to the outside is equipped with a one-way valve, a reversing solenoid valve, a digital barometer, and a servo variable pump system, which are used to change the pressure of the energy storage device by increasing or decreasing the air pressure in the inner cavity.

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