Multi-station variable distance flow line system

Abstract

The application discloses a multi-station variable-distance flow line system, which comprises a flow line body and a plurality of jacking stations arranged along the axial direction of the flow line body in sequence, and each jacking station is provided with an independent jacking module; the flow line body is formed by two vertical plates to form a conveying flow channel, the jacking rod of the jacking module is arranged outside the flow line body, and the jacking operation does not intrude into the inside of the flow channel throughout the process, so that the conveying flow channel remains unblocked when the carrier disc is jacked. Each jacking station is independently controlled, and the jacking operation can be synchronously or separately performed, and the same through conveying flow channel is shared. The jacking operation and the main line conveying are parallel and do not interfere with each other, the production rhythm and the utilization rate of the equipment can be significantly improved, the equipment floor area is reduced, and the high-efficiency continuous conveying demand of the precise carrier disc is met.

Description

Technical Field

[0001] This invention relates to the field of automated assembly line conveying equipment technology, and in particular to a multi-station variable-pitch assembly line system. Background Technology

[0002] In semiconductor precision manufacturing processes, boat-mounted variable-pitch production lines typically employ a single-layer conveyor architecture. The lifting and pitch-changing mechanism is mounted directly above the conveyor channel, with lifting supports, drive cylinders, and other functional components vertically positioned in the center of the channel. When the lifting module raises the workpiece carrier to adjust the pitch, the lifting structure completely occupies the vertical space of the conveyor channel, blocking the lower conveyor. This makes the station lifting and pitch-changing operations completely mutually exclusive with the main material conveying, allowing only one batch of work to be carried out at a time on the same track. This results in significant downtime, hindering production cycle time and making parallel material flow between upper and lower layers impossible. Furthermore, the capacity of conventional single-station variable-pitch structures is extremely limited. If a production line requires multiple pitch-changing processes, it must be achieved by connecting multiple independent devices in series. This not only occupies a large amount of installation space in the workshop but also significantly increases equipment procurement and daily maintenance costs, resulting in extremely poor production line layout flexibility.

[0003] Meanwhile, existing boat trays are prone to rebounding, slipping, and rigid collisions during start-up, stop-and-go positioning due to impacts, leading to carrier misalignment and the risk of damaging internal precision workpieces during material handling. This results in a high product scrap rate and makes it difficult to guarantee overall conveying stability. Furthermore, the flow channel width of variable-pitch conveyors is a fixed, non-adjustable structure, which cannot flexibly adapt to conveying operations with boat trays of various widths. When changing products, the entire flow channel component must be disassembled and replaced, resulting in long changeover and debugging cycles and poor equipment adaptability.

[0004] In summary, existing conveyor lines generally suffer from drawbacks such as jacking operations disrupting the main line, low conveying efficiency, large equipment footprint, easy collisions during transport, and poor specification compatibility. Summary of the Invention

[0005] The purpose of this invention is to provide a multi-station variable-pitch production line system to solve the aforementioned technical problems in the prior art. The specific technical solution is as follows: A multi-station variable-pitch production line system includes a streamlined body and multiple lifting stations arranged sequentially along the axial direction of the streamlined body. Each lifting station includes a lifting module mounted on the streamlined body. The streamlined body includes a first vertical plate and a second vertical plate arranged accordingly. A conveying channel with a top opening is formed between the first vertical plate and the second vertical plate. The conveying channel is used for conveying a pallet. The lifting module includes a lifting fixing plate disposed below the conveying channel, multiple lifting rods passing through the lifting fixing plate, and lifting fixing frames and lifting floating plates respectively disposed at the upper and lower ends of the lifting rods. The lifting floating plate can drive the pallet on the lifting fixing frame to move in the vertical direction of the conveying channel. The lifting rods are disposed on the outside of the streamlined body so that the conveying channel remains unobstructed after the lifting fixing frame lifts the pallet above the conveying channel.

[0006] Furthermore, the lifting module also includes a drive motor located below the lifting floating plate, and a transmission assembly connecting the drive motor and the lifting fixed plate. The transmission assembly includes a lead screw pair and a guide column passing through the lifting floating plate, and a linear bearing sleeved on the lifting rod. The linear bearing is located on the lifting fixed plate, and the lead screw pair is connected to the lifting floating plate.

[0007] Furthermore, the lifting fixing frame includes a front frame arm and a rear frame arm arranged axially along the conveying channel, as well as a left frame arm and a right frame arm arranged axially. A light-shielding plate is fixedly installed on the front frame arm or the rear frame arm of the lifting fixing frame, and a lifting detection photoelectric unit is installed on the first or second vertical plate corresponding to the light-shielding plate. The lifting detection photoelectric unit includes an origin photoelectric sensor and a position photoelectric sensor arranged vertically at intervals, which are used to detect the origin state and the lifting position state of the loading plate on the lifting module by sensing the position of the light-shielding plate.

[0008] Furthermore, the lifting module also includes a pin fixing plate mounted between the front arm and the rear arm, and multiple pallet support blocks mounted on the front arm and the rear arm. The pin fixing plate is provided with a coarse positioning pin at a diagonal position in the first direction. The pallet support blocks are configured as elastic buffer supports to support the pallets and buffer the lifting impact force.

[0009] Furthermore, the lifting station also includes a flexible limiting module correspondingly disposed above the lifting module; the flexible limiting module includes a limiting main board and precision positioning pins disposed on the lower surface of the limiting main board, the two precision positioning pins being located at diagonally opposite positions on the limiting main board in the second direction, the second direction being intersected with the first direction.

[0010] Furthermore, the flexible limiting module is also equipped with at least one set of flexible spring-loaded ejection mechanisms; the flexible spring-loaded ejection mechanism includes a pusher block, a rotating pin, and an elastic reset member. The elastic reset member passes through one side of the pusher block, which has an L-shaped cross-section, and the other side of the pusher block protrudes downward from the lower surface of the limiting main board. The pusher block is hinged to the limiting main board through the rotating pin. When the carrier plate is lifted into position, the pusher block is lifted by the carrier plate and compresses the elastic reset member. When the carrier plate descends, the elastic reset member releases its elastic force, driving the pusher block to swing downward around the rotating pin to push the carrier plate and assist the carrier plate in disengaging from the precision positioning pin.

[0011] Furthermore, the streamlined body also includes a base plate connecting the lower ends of the first and second upright plates, a variable pitch adjustment slide rail set on the base plate, and a belt roller module set on the inner side of the first and second upright plates. The front and rear ends of the first upright plate and / or the front and rear ends of the second upright plate are set on the variable pitch adjustment slide rail to adjust the width of the conveying channel between the first and second upright plates to adapt to different sized trays.

[0012] Furthermore, the lifting station has a discharge side and a feed side on the front and rear sides along the conveying channel axis, respectively. Each lifting station's discharge end is equipped with a blocking cylinder module. The blocking cylinder module includes a cylinder base fixed on the base plate of the streamline body, a stop block, and a blocking cylinder connecting the stop block and the cylinder base. The blocking cylinder is vertically fixed and is used to drive the stop block to lift and lower to achieve the blocking and release of the pallet. The stop block is made of elastic buffer material to absorb the impact when the pallet is stopped. A proximity switch is installed on the stop block to detect the position of the pallet.

[0013] Furthermore, a check module is provided on the feeding side of each lifting station; the check module includes a check fixing seat, a one-way check component located above the check fixing seat, and a check adjusting block connecting the check fixing seat and the one-way check component. The middle part of the one-way check component is hinged to the top of the check adjusting block. The bottom of the stop end of the one-way check component is connected to the check adjusting block through an elastic element. A roller group is provided on the stop end, and a counterweight is provided on the drive end of the one-way check component. The stop end is located between the drive end and the corresponding blocking cylinder module. Under normal conditions, the stop end protrudes upward from the conveying surface of the conveying channel under the action of the elastic element, allowing the pallet to pass only in the conveying direction. When the pallet moves in the reverse direction, the one-way check component locks to restrict the pallet from sliding back.

[0014] Furthermore, the streamlined body also includes a belt tensioning module disposed on the outside of the first and second upright plates; the belt tensioning module includes a fixing block connected to the streamlined body, an adjustment part connected to the belt idler pulley on the belt roller module, and an adjustment bolt connecting the adjustment part and the fixing block, and the adjustment part is provided with a vertical elongated slot.

[0015] The multi-station variable-pitch production line system of the present invention has the following advantages: 1. The system adopts a layered parallel architecture with externally mounted lifting rods, ensuring that the lifting operation does not intrude into the internal passage space of the conveyor flow. The pallet lifting process and the main conveying process can be carried out simultaneously without interference, fundamentally solving the pain point of traditional assembly line lifting operations that must interrupt the main conveyor. Multiple independently controlled lifting stations are arranged along the conveying direction, which can perform operations simultaneously or at different times. The system can realize parallel processing of multiple processes, effectively improving the overall equipment utilization rate and production cycle time, and reducing the workshop installation space occupied by multiple equipment connected in series.

[0016] 2. The lifting transmission structure, which adopts a lead screw pair and a drive motor, can achieve precise programmable adjustment of the lifting stroke. Compared with traditional cylinder lifting, it has higher repeatability and speed adjustment flexibility, which is suitable for the operation requirements of semiconductor precision carriers. At the same time, the multi-stage guiding system composed of guide columns and linear bearings of lifting rods can effectively bear the off-center load torque, avoid jamming and tilting problems during the lifting process, and ensure the levelness and positioning stability of the carrier.

[0017] 3. The square-frame hollow lifting and fixing frame is adopted, which reduces its own weight and driving load while ensuring load-bearing rigidity, and also minimizes the obstruction of the conveying channel below. The groove of the upright plate can provide lifting clearance space for the frame arm and auxiliary limit in the front and rear directions. With the help of the light shield and the dual-point photoelectric detection unit, it can realize precise closed-loop detection of the lifting origin and the final position, ensuring that the lifting height is consistent each time, and improving the controllability and reliability of equipment operation.

[0018] 4. The use of diagonally asymmetrically arranged coarse positioning pins enables rapid coarse centering of the carrier tray, while also providing a foolproof function to prevent subsequent operational failures caused by misplacement of the carrier tray; the elastic carrier tray support block can absorb the impact energy during the lifting and unloading process, preventing rigid collisions between the carrier tray and the support structure, and preventing precision workpieces inside the carrier tray from jumping out and shifting due to excessive impact force, effectively reducing the product scrap rate; the integrated terminal block can organize the wiring at the workstation, facilitating later inspection, maintenance and component replacement.

[0019] 5. A two-stage positioning system with coarse bottom positioning and fine top positioning is adopted. The two sets of positioning pins are arranged diagonally in different directions, which not only avoids jamming caused by over-positioning, but also constrains the planar displacement and deflection of the carrier plate. The positioning accuracy can meet the high-precision material handling requirements of the robot. The frame-shaped hollow limit main plate can completely avoid the workpiece bearing area of ​​the carrier plate and will not interfere with the material handling trajectory above, making it suitable for various material handling operation scenarios.

[0020] 6. The device adopts a purely mechanical passive flexible rebound unloading mechanism, which can complete the unloading action by relying solely on the elastic potential energy stored during the lifting process of the carrier plate. No additional drive components and control logic are required. The structure is compact and reliable and does not increase the complexity of system control. When the carrier plate descends, the feeding block can actively apply downward feeding force to help the carrier plate smoothly disengage from the high-precision positioning pin, effectively avoiding carrier plate snagging and jamming failures, improving equipment operation stability, and reducing the frequency of manual intervention.

[0021] 7. The structure design of variable pitch adjustable slide rail and sliding vertical plate can flexibly adjust the width of the conveying channel to adapt to different sizes and specifications of pallets. When changing products, there is no need to replace the entire conveying mechanism, which reduces equipment purchase costs and shortens the commissioning time of production line changeover. The belt roller modules evenly arranged along the conveying direction can stably support the conveyor belt and ensure the straightness and smooth operation of long-distance conveying.

[0022] 8. An independent blocking cylinder module is set at the discharge end. The three-axis cylinder can withstand the radial impact force when the pallet stops. Long-term use is less prone to piston rod wear, resulting in a longer service life and more stable stopping position accuracy. The stopping block made of elastic buffer material can absorb the stopping kinetic energy and reduce the rebound amplitude of the pallet. Combined with the electrical detection of the proximity switch and the mechanical limit of the stopping surface, it forms a double guarantee, which can accurately confirm the position of the pallet and avoid the risk of tilting or overturning the pallet during lifting, thus improving the safety of equipment operation.

[0023] 9. The feed side is equipped with a one-way check valve module, which only allows the pallet to pass in the forward direction. This can effectively counteract the backward rebound force after the pallet stops, and also prevent the pallet from sliding back when the equipment stops suddenly, ensuring that the pallet always stays within the preset lifting range. The stop end is equipped with a roller group to replace sliding friction with rolling friction, which reduces the conveying resistance and prevents scratching the bottom surface of the pallet. The elastic element and counterweight are designed with matching parameters to balance the reliability of the check valve and the smoothness of the conveying. The adjustable structure can also flexibly adapt to pallets of different thicknesses.

[0024] 10. A belt tensioning module is installed on the outside of the vertical plate. The belt idler pulley can be moved vertically by adjusting the bolts to achieve stepless adjustment of the conveyor belt tension. The debugging and operation are convenient. It can effectively compensate for the natural slack of the belt after long-term operation, ensure that the belt is always in a proper tension state, maintain a stable conveying speed and positioning accuracy, extend the belt service life, and reduce equipment maintenance costs. Attached Figure Description

[0025] Figure 1 This is an overall schematic diagram of the multi-station variable pitch production line system of the present invention.

[0026] Figure 2 This is a schematic diagram of the streamline body in the multi-station variable pitch assembly line system of the present invention.

[0027] Figure 3 This is a schematic diagram of the lifting module in the multi-station variable pitch production line system of the present invention.

[0028] Figure 4 This is a schematic diagram of the lifting and fixing frame in the multi-station variable pitch production line system of the present invention.

[0029] Figure 5 This is a schematic diagram of the flexible limiting module in the multi-station variable pitch production line system of the present invention.

[0030] Figure 6 This is a schematic diagram of the normal operation of the flexible rebound unloading mechanism in the multi-station variable pitch production line system of the present invention.

[0031] Figure 7 This is a schematic diagram of the compressed state of the flexible rebound unloading mechanism in the multi-station variable pitch production line system of the present invention.

[0032] Figure 8 This is a schematic diagram of the driven gear in the multi-station variable pitch production line system of the present invention.

[0033] Figure 9 This is a schematic diagram of the motor drive module in the multi-station variable pitch production line system of the present invention.

[0034] Figure 10 This is a schematic diagram of the blocking cylinder module in the multi-station variable pitch production line system of the present invention.

[0035] Figure 11 This is a schematic diagram of the check valve module in the multi-station variable pitch production line system of the present invention.

[0036] Figure 12 This is a schematic diagram of the belt tensioning module in the multi-station variable pitch production line system of the present invention.

[0037] Figure 13 This is a schematic diagram of the deceleration photoelectric module in the multi-station variable pitch production line system of the present invention. Detailed Implementation

[0038] To better understand the purpose, structure, and function of this invention, the multi-station variable pitch production line system of this invention will be described in detail below with reference to the accompanying drawings.

[0039] like Figures 1 to 13 As shown, the multi-station variable-pitch production line system provided by the present invention is mainly suitable for continuous conveying and segmented lifting operations of semiconductor boat trays and precision workpiece trays. After the trays at the lifting station are lifted, the main conveying channel is maintained to ensure continuous flow, which greatly improves the operating cycle time and equipment utilization rate of the production line.

[0040] The conveying system includes a streamlined body 1 and multiple lifting stations arranged sequentially along the axial direction of the streamlined body 1. Each lifting station is equipped with an independent lifting module 2. The streamlined body 1 includes a first vertical plate 3 and a second vertical plate 4 arranged opposite each other, forming a conveying channel with a top opening between the two vertical plates. A rectangular pallet can be continuously conveyed along the axial direction of the conveying channel. The lifting module 2 includes a lifting fixing plate 5 set below the conveying channel. Multiple lifting rods 6 are vertically inserted through the lifting fixing plate 5. The upper and lower ends of the lifting rods 6 are respectively connected to the lifting fixing frame 7 and the lifting floating plate 8. During operation, the lifting floating plate 8 can drive the lifting fixing frame 7 and the pallet it carries to move up and down vertically along the conveying channel. All lifting rods 6 are located on the outer side of the two vertical plates of the streamlined body 1. During the lifting process, the movement trajectories of the lifting rods 6 and the lifting fixing frame 7 do not occupy the internal passage space of the conveying channel, ensuring that the conveying channel remains unobstructed while the lifting module 2 lifts the pallet above the conveying channel. Multiple lifting stations are independently controlled, allowing for simultaneous or separate lifting operations. All stations share the same conveying channel running along the conveying direction. This layered layout allows the upper-level stations to perform lifting operations while the lower-level conveying channel continuously transports other pallets without interference, effectively reducing production cycle time. Actual operating condition calculations show that this architecture can increase the overall production cycle time of the equipment by more than 40%. Furthermore, a single unit integrates multiple lifting stations, enabling parallel processing of multiple processes without the need for multiple units to be connected in series, effectively saving workshop installation space and reducing equipment procurement costs. The functional modules of the entire system adopt a modular integrated design, facilitating easy disassembly and maintenance, and allowing for rapid replacement of spare parts and product changeover adjustments.

[0041] The lifting module 2 also includes a drive motor 9 located below the lifting floating plate 8, and a transmission assembly connecting the drive motor 9 and the lifting fixed plate 5. The lifting fixed plate 5 is fixed to the base plate at the bottom of the streamlined body 1, providing a stable installation reference for the entire lifting module 2. The transmission assembly includes a lead screw pair 10 and a guide column 11 that pass vertically through the lifting floating plate 8, and linear bearings 12 correspondingly sleeved on the outer periphery of each lifting rod 6. The linear bearings 12 are fixedly installed on the lifting fixed plate 5, and the moving end of the lead screw pair 10 is fixedly connected to the lifting floating plate 8. The drive motor 9 adopts a stepper screw motor module, and the lifting stroke can be flexibly set by the program to adapt to different height operation requirements. It has a wide speed range and high positioning accuracy. During operation, the rotational motion output by the drive motor 9 is converted into vertical linear motion through the lead screw pair 10, driving the lifting floating plate 8 and the lifting rod 6 to rise and fall synchronously. Compared with traditional cylinder lifting, it can achieve more precise height control and higher repeatability positioning accuracy, which is suitable for the operation requirements of semiconductor precision carriers. The guide column 11 and the linear bearing 12 on the lifting rod 6 together form a multi-stage linear guide structure, which can effectively counteract the off-center load torque, avoid jamming and tilting during the lifting process, ensure that the carrier plate always remains in a horizontal state, and further improve the stability and accuracy of positioning.

[0042] The lifting and fixing frame 7 includes a front arm 13 and a rear arm 14 arranged opposite each other along the axial direction of the conveying channel, and a left arm 15 and a right arm 16 arranged opposite each other along the width direction of the channel. The four arm segments are connected end to end to form a square frame-shaped load-bearing structure. The lifting and fixing frame 7 adopts a hollow square frame structure, which reduces its own weight while ensuring load-bearing rigidity, reducing the load on the drive motor 9, and minimizing obstruction of the passage space of the conveying channel below. Among them, the top ends of the two lifting rods 6 are connected to the left arm 15 located outside the first upright plate 3, and the top ends of the other two lifting rods 6 are connected to the right arm 16 located outside the second upright plate 4. Correspondingly, the first upright plate 3 and the second upright plate 4 are provided with a front groove and a rear groove. Both grooves extend vertically and are open at the top. The front groove corresponds to the position of the front arm 13 of the lifting fixing frame 7, and the rear groove corresponds to the position of the rear arm 14. This provides clearance for the lifting and lowering movement of the arm, and also forms an auxiliary limit for the front and rear direction of the arm, further improving the lifting stability.

[0043] A light-shielding plate 17 is fixed to the top of the front arm 13 or rear arm 14 of the lifting floating plate 8. A lifting detection photoelectric unit 18 is fixedly installed on the first vertical plate 3 or the second vertical plate 4 corresponding to the position of the light-shielding plate 17. The lifting detection photoelectric unit 18 includes an origin photoelectric sensor and a position photoelectric sensor arranged vertically at intervals. Both photoelectric sensors use U-shaped slot photoelectric switches. The detection signal is triggered when the light-shielding plate 17 enters the slot during the lifting movement. It has a fast response speed, strong anti-interference ability, and can accurately capture key nodes of the lifting stroke. By sensing the blocking position of the light-shielding plate 17, the initial origin state and the lifting position state of the lifting module 2 can be identified respectively. The photoelectric unit is fixed to the vertical plate and does not move with the lifting mechanism. The detection benchmark is stable and reliable, and it can cooperate with the control system to achieve closed-loop control of the lifting stroke, avoiding overtravel or under-lifting, and ensuring the consistency of the lifting height each time.

[0044] A rectangular pin fixing plate 19 is installed between the front arm 13 and the rear arm 14 of the lifting fixing frame 7. Multiple tray support blocks 21 are also distributed on the top surfaces of the front arm 13 and the rear arm 14. A terminal block 22 is installed on the left arm 15 or the right arm 16. The wiring of the detection components and pneumatic components of the lifting station can be uniformly collected in the terminal block 22, making the station wiring neat and clear, facilitating later inspection, maintenance, and component replacement. The pin fixing plate 19 has a coarse positioning pin 20 at each diagonal position in the first direction. The two coarse positioning pins 20 protrude vertically upwards and can be inserted into the first positioning hole of the tray to achieve coarse positioning of the tray. Furthermore, the two coarse positioning pins 20 are arranged asymmetrically diagonally, forming a foolproof structure. If the tray is placed in the wrong direction, it cannot cooperate with the pin, thus preventing subsequent material handling failures caused by incorrect loading direction from the source. The carrier support block 21 uses an elastic buffer support, such as an elastic PG. When the carrier falls onto the lifting fixing frame 7 and the lifting starts, the carrier support block 21 can absorb the impact energy through elastic deformation, avoiding rigid collision between the carrier and the support structure. This protects the carrier and the internal precision workpieces and reduces rebound and displacement. When the carrier is lifted into position and is restricted by the upper structure, the carrier support block 21 can also retract adaptively, which can effectively prevent the internal workpieces from jumping out or shifting due to excessive impact force when the carrier contacts the limit, greatly reducing the risk of scrapping precision workpieces.

[0045] Each lifting station also includes a flexible limiting module 23 correspondingly positioned above the lifting module 2. The flexible limiting module 23 includes a rectangular frame-shaped limiting main board 24 and precision positioning pins 25 positioned on the lower surface of the limiting main board 24. The limiting main board 24 is fixed above the conveying channel by a bracket. The two precision positioning pins 25 are respectively arranged at diagonal positions in a second direction of the limiting main board 24, and the second direction is intersected with the first direction of the coarse positioning pins 20. During the lifting process, the coarse positioning pins 20 at the bottom first complete the initial centering, limiting the large displacement of the pallet. As the lifting stroke advances, the precision positioning pins 25 at the top are inserted into the second positioning holes on the pallet to complete the final positioning with higher precision. The system adopts a two-stage positioning scheme with coarse bottom positioning and fine top positioning. The two sets of positioning pins are diagonally intersected, which not only avoids jamming caused by over-positioning, but also constrains the planar displacement and deflection of the carrier plate, resulting in higher positioning accuracy and meeting the high-precision material handling requirements of the robot. The frame-shaped hollow design of the limit motherboard 24 can completely avoid the workpiece bearing area of ​​the carrier plate and will not interfere with the material handling trajectory of the robot above, making it suitable for various material handling operation scenarios.

[0046] The flexible limiting module 23 is also equipped with at least one set of flexible spring-loaded ejection mechanisms 26. The flexible spring-loaded ejection mechanism 26 includes a material-pushing block 27, a rotating pin 28, and an elastic reset member 29. The material-pushing block 27 has an L-shaped cross-section, with one arm through which the elastic reset member 29 passes, and the other arm protruding downwards from the lower surface of the limiting main board 24. The material-pushing block 27 is hinged to the limiting main board 24 by the rotating pin 28. During the process of lifting the tray into position, the upper surface of the tray will contact and lift the lower end of the material-pushing block 27, causing the material-pushing block 27 to swing around the rotating pin 28 and compress the elastic reset member 29. When the material is picked up and the tray descends with the lifting module 2, the compressed elastic reset member 29 gradually releases its elastic force, driving the material-pushing block 27 to swing in the opposite direction. Its lower end pushes the upper surface of the tray downwards, applying a downward auxiliary ejection force to the tray. This structure requires no additional drive components or control logic; it relies solely on the elastic potential energy stored during the lifting process of the carrier plate to complete the unloading action. The structure is compact and reliable, without increasing the system's control complexity. The flexible spring-loaded unloading mechanism 26 addresses the pin jamming problem in precision positioning scenarios: due to the high precision of the fit between the precision positioning pin 25 and the second positioning hole of the carrier plate, relying solely on the carrier plate's own weight may prevent it from smoothly disengaging from the pin, easily leading to carrier plate jamming. The active material ejection by the spring-loaded unloading mechanism ensures that the carrier plate stably disengages from the positioning pin and smoothly falls back into the conveyor channel with the lifting module 2, improving the reliability of equipment operation and reducing manual intervention.

[0047] The streamlined body 1 also includes a base plate connecting the lower ends of the first upright plate 3 and the second upright plate 4. A variable-pitch adjustment slide rail 30 is provided on the base plate. Belt roller modules 31 are arranged on the inner sides of both upright plates, with dozens of belt roller modules 31 evenly arranged along the conveying direction on the inner sides of the two upright plates. These modules support and guide the conveyor belt, ensuring the straightness and operational stability of the belt during long-distance conveying. The conveyor belt is wound around the belt roller modules 31, providing conveying power to the pallets. A motor drive module 32 is provided at the end of the streamlined body 1. The drive unit 55 of the motor drive module 32 is locked to one end of the upright plate via a motor fixing plate 56. A drive gear 57 is installed at its output end, transmitting power to the driven gear 54 via a chain. This drives the conveyor belt wound around the idler wheel and belt roller modules 31 to circulate, providing continuous and stable power for the pallet conveying of the entire streamlined body. The front and rear ends of the first upright plate 3, or the front and rear ends of the second upright plate 4, are slidably mounted on the variable pitch adjustment slide rail 30. Their positions can be adjusted along the width of the conveying channel, thereby changing the width of the conveying channel between the two upright plates to accommodate trays of different sizes. After the channel width is adjusted, the upright plates can be fixed to the variable pitch adjustment slide rail 30 using locking devices to prevent channel width deviation during conveying and ensure conveying accuracy. The adjustable channel design allows a single unit to be compatible with multiple tray models. When changing products, only the channel width needs to be adjusted, without replacing the entire conveying mechanism, reducing equipment procurement costs and shortening the commissioning time for production line changes.

[0048] Each lifting station has a feeding side and a discharging side on both sides along the axial direction of the conveying channel, respectively. A blocking cylinder module 33 is provided at the discharging end of each lifting station. The blocking cylinder module 33 includes a cylinder base 34 fixed to the base plate of the streamline body 1, a stop block 35, and a blocking cylinder 36 vertically connected between the cylinder base 34 and the stop block 35. The output end of the blocking cylinder 36 is connected to an adjusting base plate 37, on which the stop block 35 is mounted. The adjusting base plate 37 can be finely adjusted back and forth along the conveying direction to precisely adjust the stopping point of the stop block 35, ensuring that the stopping position of the pallet precisely corresponds to the coarse positioning pin 20 on the lifting fixing frame 7. The blocking cylinder 36 can drive the stop block 35 to move up and down, thereby achieving the stopping and release of the pallet. In this embodiment, the blocking cylinder 36 is a three-axis cylinder, which can withstand the radial impact force generated when the pallet stops. It is also less prone to piston rod wear over long-term use, resulting in a longer service life and more stable stopping position accuracy. The stop block 35 is made of urethane rubber with a hardness of 90 degrees. It has sufficient hardness to prevent excessive deformation after impact, and its elasticity can absorb the stopping kinetic energy, effectively reducing the rebound amplitude of the carrier plate and protecting the carrier plate and internal workpieces. The stop block 35 also integrates a proximity switch 38, which can detect in real time whether the carrier plate is stopped in place. If an abnormal position of the carrier plate is detected, the control system will prevent the lifting module 2 from starting, avoiding the risk of lifting off-center or tipping the carrier plate. The stopping surface of the stop block 35 also constitutes a mechanical limit, forming a double guarantee with the electrical detection of the proximity switch 38, ensuring that the carrier plate stays in the accurate lifting position and improving the safety of equipment operation.

[0049] Each lifting station has a check valve module 39 installed on its feed side. The check valve module 39 includes a check valve fixing seat 40 fixed inside the first vertical plate 3 or the second vertical plate 4, a one-way check valve 41 located above the check valve fixing seat 40, and a check valve adjusting block 42 connecting the check valve fixing seat 40 and the one-way check valve 41. The check valve fixing seat 40 can be adjusted vertically for a slight height adjustment. Combined with the front-to-back adjustable check valve adjusting block 42, it can flexibly adapt to pallets of different thicknesses and conveying surface heights, ensuring the adaptability and reliability of the check valve action. The one-way check valve 41 is hinged to the top of the check valve adjusting block 42 at its middle. Its end facing the discharge side is the stop end, and the bottom of the stop end is connected to the check valve adjusting block 42 via an elastic element 43. A roller assembly is provided at the top of the stop end; the roller assembly at the stop end includes two parallel rollers 44. When the pallet passes through, rolling friction replaces sliding friction, effectively reducing conveying resistance and preventing scratches on the bottom surface of the pallet. The end of the one-way check valve 41 facing the feed side is the drive end, and a counterweight 45 is provided on the drive end. The stop end is located between the drive end and the corresponding blocking cylinder module 33. Under normal conditions, the stop end protrudes upward under the combined action of the elastic element 43 and the counterweight 45, exceeding the conveying surface of the conveying channel. When the tray passes through in the forward direction of the conveying, the bottom surface of the tray presses over the roller assembly, pressing the stop end downward, allowing the tray to pass smoothly. After the tray has completely passed, the stop end automatically resets. If the tray rebounds backward due to the impact of the stop or if it tends to slide backward when the equipment stops suddenly, the end face of the stop end will directly abut against the rear edge of the tray, restricting the tray from moving backward and ensuring that the tray always stays within the preset lifting range, thus avoiding positioning failure due to backward sliding. The elastic force parameters of the elastic element 43 are strictly controlled during the design process to ensure that the lifting force of the elastic element 43 on the stop end is not greater than the weight of the carrier plate itself. This avoids the carrier plate from shaking and jumping due to excessive elastic force, and prevents the precision workpieces inside the carrier plate from shifting and collapsing. The elastic force of the elastic element 43 and the weight of the counterweight 45 are matched and designed to ensure reliable anti-rebound force without shaking and jumping due to excessive elastic force, thus balancing the smoothness of the conveying and the reliability of the anti-rebound mechanism.

[0050] The streamlined body 1 also includes a belt tensioning module 46 disposed on the outer side of the first vertical plate 3 and the second vertical plate 4. The belt tensioning module 46 includes a fixing block 47 fixedly connected to the streamlined body 1, an adjusting part 49 connected to the belt idler pulley 48 in the belt roller module 31, and an adjusting bolt 50 connecting the adjusting part 49 and the fixing block 47. The fixing block 47 is locked to the outer wall of the vertical plate, the adjusting part 49 is connected to the side wall of the vertical plate through a vertical elongated slot, and the shaft of the belt idler pulley 48 is fixedly installed on the adjusting part 49. After long-term operation, the conveyor belt will naturally loosen, affecting the stability of the conveying speed and the positioning accuracy. By rotating the adjusting bolt 50, the adjusting part 49 can be moved vertically along the elongated slot, thereby changing the height of the belt idler pulley 48, realizing stepless adjustment of the conveyor belt tension. The adjustment is convenient and the positioning is reliable, ensuring that the belt is always in a suitable tension state, extending the belt service life, and maintaining stable conveying performance.

[0051] Each lifting station is equipped with a deceleration photoelectric module 53 on the feeding side. Before the pallet enters the station range, it is first sensed by the deceleration photoelectric module. The control system then reduces the running speed of the conveyor belt, so that the pallet approaches the stop position at a low speed, reducing the impact of stopping and ensuring that the pallet stops smoothly. Each lifting station is also equipped with a feeding detection photoelectric module 52 and a discharging detection photoelectric module 51 at the front and rear, respectively. Together with the control system, the position of each pallet in the flow channel can be tracked in real time and recorded statistically to ensure the accuracy of the timing when multiple pallets are transported in parallel and to maintain the stability of the flow channel operation.

[0052] The overall workflow of the system is as follows: The carrier tray is conveyed from upstream into the conveyor channel of the streamline body 1 and moves forward along the conveying direction under the drive of the belt. When the carrier tray moves to the front of the lifting station, the deceleration photoelectric module 53 detects the carrier tray signal, and the control system controls the belt to decelerate, so that the carrier tray enters the station range at a low speed. The carrier tray first passes through the check module 39 on the feeding side. The bottom surface presses down the roller 44 of the check component, causing the stop end to sink. After passing smoothly, the stop end automatically resets. Then the carrier tray continues to move forward until it is stopped by the blocking cylinder 36 raised at the discharge end. The urethane material of the stop block 35 absorbs the impact, and in conjunction with the reverse limit of the check module 39, the carrier tray is stably stopped at the preset lifting position. After the proximity switch 38 on the stop block 35 detects that the carrier tray has arrived, it sends a position signal to the control system.

[0053] Upon receiving the arrival signal, the stepper screw motor of the lifting module 2 starts, driving the lifting floating plate 8 upward through the screw pair 10, which in turn drives the lifting fixed frame 7 to move upward synchronously. The carrier plate support block 21 on the lifting fixed frame 7 first contacts the bottom surface of the carrier plate to buffer the lifting impact, and then the coarse positioning pin 20 is inserted into the first positioning hole of the carrier plate to complete the coarse centering. As the lifting stroke continues, the carrier plate gradually approaches the upper flexible limiting module 23, and the fine positioning pin 25 is inserted into the second positioning hole of the carrier plate to complete the precise positioning. At the same time, the carrier plate lifts the material feeding block 27 of the flexible rebound unloading mechanism 26 and compresses the elastic reset component 29 to store energy. After the photoelectric sensor detects the light shield 17 when the lifting is in place, the lifting module 2 stops rising, and the carrier plate remains at the working height, waiting for the upper robot arm to complete the material handling or other processes. During this process, all moving parts of the lifting module 2 are located on both sides and above the conveying channel, and the inside of the channel remains open. Other carrier plates to be processed can pass normally from the bottom channel without stopping the machine.

[0054] After the operation is completed, the lifting module 2 lowers the carrier tray, and the compressed elastic reset member 29 releases its elasticity, driving the material feeding block 27 to push the carrier tray downwards, assisting the carrier tray in disengaging from the precision positioning pin 25. The carrier tray falls back onto the conveying surface of the conveying channel with the lifting fixing frame 7, and the lifting module 2 continues to descend to the origin position. After the origin photoelectric trigger is activated, the lifting action stops. Subsequently, the blocking cylinder 36 descends to release the carrier tray, which flows out of the lifting station under the drive of the belt and enters the next process or downstream equipment. In this embodiment, two lifting stations are provided, and the carrier tray can pass through each station in sequence to complete the corresponding process. Each station can operate independently and synchronously without interference.

[0055] The terms “above,” “below,” and “within” as used above include the number itself; the terms “exceeding” and “excluding” do not include the number itself.

[0056] The present invention has been further described above with reference to specific embodiments. However, it should be understood that the specific descriptions herein should not be construed as limiting the substance and scope of the present invention. Various modifications made to the above embodiments by those skilled in the art after reading this specification are all within the scope of protection of the present invention. The various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the embodiments of the present invention will not further describe various possible combinations.

[0057] If the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

Claims

1. A multi-station variable-pitch production line system, characterized in that, The system includes a streamlined body and multiple lifting stations arranged sequentially along the axial direction of the streamlined body. Each lifting station includes a lifting module mounted on the streamlined body. The streamlined body includes a first vertical plate and a second vertical plate arranged accordingly. A conveying channel with a top opening is formed between the first vertical plate and the second vertical plate. The conveying channel is used for conveying a pallet. The lifting module includes a lifting fixing plate located below the conveying channel, multiple lifting rods passing through the lifting fixing plate, and lifting fixing frames and lifting floating plates respectively located at the upper and lower ends of the lifting rods. The lifting floating plate can drive the pallet on the lifting fixing frame to move in the vertical direction of the conveying channel. The lifting rods are located on the outside of the streamlined body so that the conveying channel remains unobstructed after the lifting fixing frame lifts the pallet above the conveying channel.

2. The multi-station variable-pitch assembly line system according to claim 1, characterized in that, The lifting module also includes a drive motor located below the lifting floating plate, and a transmission assembly connecting the drive motor and the lifting fixed plate. The transmission assembly includes a lead screw pair and a guide column passing through the lifting floating plate, and a linear bearing sleeved on the lifting rod. The linear bearing is located on the lifting fixed plate, and the lead screw pair is connected to the lifting floating plate.

3. The multi-station variable-pitch assembly line system according to claim 2, characterized in that, The lifting and fixing frame includes a front frame arm and a rear frame arm arranged axially along the conveying channel, as well as a left frame arm and a right frame arm arranged axially. A light-shielding plate is fixedly installed on the front frame arm or the rear frame arm of the lifting and fixing frame. A lifting detection photoelectric unit is installed on the first or second vertical plate corresponding to the light-shielding plate. The lifting detection photoelectric unit includes an origin photoelectric sensor and a position photoelectric sensor arranged vertically at intervals, which are used to detect the origin state and the lifting position state of the loading plate on the lifting module by sensing the position of the light-shielding plate.

4. The multi-station variable-pitch assembly line system according to claim 3, characterized in that, The lifting module also includes a pin fixing plate mounted between the front arm and the rear arm, and multiple pallet support blocks mounted on the front arm and the rear arm. The pin fixing plate is provided with a coarse positioning pin at a diagonal position in the first direction. The pallet support blocks are configured as elastic buffer supports to support the pallets and buffer the lifting impact force.

5. The multi-station variable-pitch assembly line system according to claim 4, characterized in that, The lifting station also includes a flexible limiting module correspondingly disposed above the lifting module; the flexible limiting module includes a limiting main board and precision positioning pins disposed on the lower surface of the limiting main board, the two precision positioning pins being located at diagonally opposite positions on the limiting main board in a second direction, the second direction being intersected with the first direction.

6. The multi-station variable-pitch assembly line system according to claim 5, characterized in that, The flexible limiting module is also provided with at least one set of flexible spring-loaded ejection mechanisms; the flexible spring-loaded ejection mechanism includes a material-pushing block, a rotating pin, and an elastic reset member. The elastic reset member passes through one side of the material-pushing block, which has an L-shaped cross-section, and the other side of the material-pushing block protrudes downward from the lower surface of the limiting main board. The material-pushing block is hinged to the limiting main board by the rotating pin. When the carrier plate is lifted into position, the material-pushing block is lifted by the carrier plate and compresses the elastic reset member. When the carrier plate descends, the elastic reset member releases its elastic force, driving the material-pushing block to swing downward around the rotating pin to push the carrier plate and assist the carrier plate in disengaging from the precision positioning pin.

7. The multi-station variable-pitch assembly line system according to claim 4, characterized in that, The streamlined body also includes a base plate connecting the lower ends of the first and second upright plates, a variable pitch adjustment slide rail set on the base plate, and a belt roller module set on the inner side of the first and second upright plates. The front and rear ends of the first upright plate and / or the front and rear ends of the second upright plate are set on the variable pitch adjustment slide rail to adjust the width of the conveying channel between the first and second upright plates to adapt to different sized trays.

8. The multi-station variable-pitch assembly line system according to claim 1, characterized in that, The lifting station has a discharge side and a feed side on the front and rear sides along the axial direction of the conveying channel, respectively. Each lifting station's discharge end is equipped with a blocking cylinder module. The blocking cylinder module includes a cylinder base fixed to the base plate of the streamline body, a stop block, and a blocking cylinder connecting the stop block and the cylinder base. The blocking cylinder is vertically fixed and is used to drive the stop block to rise and fall to achieve the blocking and release of the pallet. The stop block is made of elastic buffer material to absorb the impact when the pallet stops. A proximity switch is provided on the stop block to detect the position of the pallet.

9. The multi-station variable-pitch assembly line system according to claim 8, characterized in that, Each lifting station has a check valve module on its feed side. The check valve module includes a check valve base, a one-way check valve located above the check valve base, and a check valve adjusting block connecting the check valve base and the one-way check valve. The middle part of the one-way check valve is hinged to the top of the check valve adjusting block. The bottom of the stop end of the one-way check valve is connected to the check valve adjusting block through an elastic element. A roller assembly is provided on the stop end. A counterweight is provided on the drive end of the one-way check valve. The stop end is located between the drive end and the corresponding blocking cylinder module. Under normal conditions, the stop end protrudes upward from the conveying surface of the conveying channel under the action of the elastic element, allowing the pallet to pass only in the conveying direction. When the pallet moves in the reverse direction, the one-way check valve locks to restrict the pallet from sliding back.

10. The multi-station variable-pitch assembly line system according to any one of claims 1 to 9, characterized in that, The streamlined body also includes a belt tensioning module disposed on the outside of the first and second upright plates; the belt tensioning module includes a fixing block connected to the streamlined body, an adjustment part connected to the belt idler pulley on the belt roller module, and an adjustment bolt connecting the adjustment part and the fixing block, and the adjustment part is provided with a vertical elongated slot.

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