Mechanical hand transmission protection device and protection method

Abstract

The application discloses a mechanical hand transmission protection device and method in the field of punch manufacturing, which comprises a main power station, the main power station is matched with an auxiliary power station, the main power station is connected with the auxiliary power station through a transmission assembly, the main power station and the auxiliary power station are connected with a pneumatic system, and the transmission assembly is connected with an arm seat of the mechanical hand. The pneumatic system provides gas source power for the main power station and the auxiliary power station, the main power station is connected with the auxiliary power station through the transmission assembly, when it is necessary to protect the mechanical hand, the main power station and the auxiliary power station cooperate with each other, the equipment is prevented from being impacted and malfunctioning through the pneumatic force, and the purpose of protecting the mechanical hand is achieved.

Description

Technical Field

[0001] This invention relates to a limit protection device in the field of stamping manufacturing. Background Technology

[0002] In the stamping manufacturing industry, robotic arms have replaced traditional manual handling due to their advantages such as high precision, high efficiency, and compact structure. However, this has also brought a series of problems such as equipment maintenance and safety hazards. Currently, most robotic arms in existing technology use gear and rack meshing to transmit power, forming a highly rigid transmission system. When an emergency occurs, due to the loss of power to the servo motor, the transfer component will continue to move due to inertia, colliding with the braked press, causing equipment damage or even safety accidents. Summary of the Invention

[0003] The purpose of this invention is to provide a protective device and method for the transmission of a robotic arm, which can ensure the high-precision operation of the robotic arm transmission system while avoiding equipment failures or even safety accidents caused by emergency situations.

[0004] To achieve the above objectives, the present invention provides a transmission protection device for a robotic arm, including an active power station and an auxiliary power station, the active power station being connected to the auxiliary power station via a transmission assembly, both the active power station and the auxiliary power station being connected to a pneumatic system, and the transmission assembly being connected to the arm base of the robotic arm.

[0005] Compared with the prior art, the beneficial effect of the present invention is that the pneumatic system provides air power to the main power station and the auxiliary power station. The main power station is connected to the auxiliary power station through the transmission component. When it is necessary to protect the robot, the main power station and the auxiliary power station cooperate with each other to avoid the equipment from being impacted and malfunctioning through pneumatic power, thereby achieving the purpose of protecting the robot.

[0006] As a further improvement of the present invention, the main power station includes a first load-bearing frame, which is horizontally fixed to the ground. A power unit base is vertically mounted on the first load-bearing frame, and a power component is vertically mounted on the power unit base. The power component includes a servo motor, which is connected to a reducer. The reducer meshes with a rack at the bottom of a movable slide via gears. The movable slide can be driven by the power component to move laterally. A longitudinal fixing plate is provided at the end of the movable slide, and a working cylinder is mounted on the longitudinal fixing plate. The working cylinder is parallel to the end of the movable slide and is a double-acting cylinder. The front end of the piston rod of the working cylinder is connected to a rod connecting block, and a magnetic switch is provided at the bottom of the working cylinder.

[0007] By controlling the servo motor to power on, the robotic arm transmission system is connected. The main power station controls the transmission components: the servo motor rotates, which drives the gear to rotate, and then drives the moving slide through the rack meshing with the gear. The moving slide drives the working cylinder, and the working cylinder drives the auxiliary power station components to slide laterally back and forth through the transmission components.

[0008] As a further improvement of the present invention, the auxiliary power station includes a second support frame, which is placed horizontally on the ground and horizontally fixed to the punch press column. A cylinder rear fixing plate and a cylinder front fixing plate are provided on the second support frame. A safety cylinder is provided between the cylinder rear fixing plate and the cylinder front fixing plate. The safety cylinder is a double-acting cylinder, and the front end of the piston rod of the safety cylinder is connected to the stroke limit frame.

[0009] This working cylinder causes the transmission component to slide laterally back and forth within the stroke limit frame. The stroke limit frame is dragged by the transmission component to the maximum displacement stroke and then stops to reduce transmission resistance.

[0010] As a further improvement of the present invention, the travel limit frame is a U-shaped structure with hollow parallel grooves machined on both sides. The length of the hollow parallel grooves matches the transfer stroke of the robot arm. A collision protection frame is provided on the second load-bearing frame. The collision protection frame is installed directly below the end of the hollow parallel groove of the travel limit frame, with a gap left at the top. A polyurethane block is provided in the groove on the back of the collision protection frame.

[0011] After the travel limit frame is dragged to its maximum displacement stroke by the transmission assembly, only the part of the transmission assembly within the parallel groove continues to slide laterally repeatedly, and its sliding stroke is limited to the length of the parallel groove of the travel limit frame.

[0012] As a further improvement of the present invention, the transmission assembly includes a cylindrical rack, the front end of which is connected to a rack connecting block, and a threaded hole is opened in the shaft at the end of the cylindrical rack. The rack limiting block is locked to the end of the cylindrical rack by bolts. The working cylinder and the safety cylinder are concentric. The rack connecting block is fixedly connected to the rod connecting block. The rack limiting block is installed and restricted in the hollow parallel groove of the stroke limiting frame, with both ends extending out of the hollow parallel groove. The cylindrical rack meshes with the eccentric gear in the arm seat. The cylindrical rack is connected to several arm seats in sequence through the rack connecting block. The transfer rod is placed horizontally on the transverse rolling bearing in the arm seat and can slide laterally in the arm seat. The arm seat is provided with a longitudinal rolling bearing that abuts against the transfer rod.

[0013] In this way, the working cylinder drives the cylindrical rack to make a lateral reciprocating motion. At this time, the rack limit block at the end of the cylindrical rack slides laterally back and forth in the parallel groove of the stroke limit frame. The stroke limit frame is dragged to the maximum displacement stroke by the rack limit block and then stops to reduce transmission resistance. Only the rack limit block in the parallel groove continues to slide laterally repeatedly, and its sliding stroke is limited to the length of the parallel groove of the stroke limit frame.

[0014] As a further improvement of the present invention, the pneumatic system includes a switching valve, which is connected to the air source in the plant and then connected to a triplet. The triplet is connected to a safety valve, which is connected to a check valve. The check valve is connected to an air tank, which is equipped with a pressure relief valve and a pressure switch. The air tank is connected to a cylinder reversing valve, which is a two-position five-way single-control valve. The air inlet P of the cylinder reversing valve is connected to the air tank, and the air outlet B of the cylinder reversing valve is connected to the port A of the safety cylinder. The air outlet A of the cylinder reversing valve is connected in series with a quick exhaust valve and then connected to the port A of the working cylinder.

[0015] When the safety valve is energized, gas flows into the storage tank at a set flow rate. When the pressure in the storage tank reaches the pressure switch threshold, a signal is sent back to the PLC. The PLC then energizes the cylinder reversing valve, allowing air to enter the working cylinder port A. The air supply to the safety cylinder port A is cut off, and the gas flowing into the working cylinder pushes the piston to move towards the bottom of the cylinder. When both the external power and air supply of the robot are cut off, the gas will not be quickly discharged through the safety valve because of the one-way valve at the inlet of the storage tank. The stored gas can ensure the switching between the two cylinders. When the cylinder reversing valve is de-energized, the valve core is reset to the normal position by the spring force, the air supply to the working cylinder port A is cut off, and the piston rod can be dragged by external force.

[0016] To achieve the above objectives, the present invention also provides a method for protecting the transmission of a robotic arm, characterized by the following steps: Step 1, preparation of the pneumatic system; Step 2, interaction between the main power station and the auxiliary power station via the transmission component; Step 3, safety transmission protection.

[0017] Compared with existing technologies, the advantages of this invention lie in its ability to quickly and safely connect or disconnect the robot's transmission components from the power source through a controllable cylinder reversing device, ensuring high-precision transmission while preventing safety accidents. This device has a compact structure, high reliability, and can effectively reduce the failure rate of robot equipment, improve safety levels, and enhance the equipment's market competitiveness.

[0018] As a further improvement to the present invention, the specific content of step 1 is as follows.

[0019] When the robotic arm starts production, after the switch valve is opened, the gas flows through the triplet to the safety valve. After the PLC checks that the safety circuit is closed, it powers on the safety valve. The gas flows into the gas tank at a set flow rate. When the pressure in the gas tank reaches the pressure switch threshold, it sends a signal back to the PLC. The PLC controls the cylinder reversing valve to be energized, and the working cylinder port A is filled with air. The air supply to the safety cylinder port A is cut off. The gas flowing into the working cylinder pushes the piston to move to the bottom of the cylinder. At the same time, the piston rod pulls the cylindrical rack to move to the right. The rack limit block installed at the end of the cylindrical rack moves to the right until it abuts and drags the stroke limit bracket.

[0020] As a further improvement to the present invention, the specific content of step 2 is as follows.

[0021] Step 2.1: When the magnetic switch of the working cylinder detects that the piston has moved to the bottom of the cylinder, the magnetic switch will send a signal to the PLC. The PLC determines that the switching of the two cylinders is complete, controls the servo motor to power on, and then issues an action command.

[0022] Step 2.2: If the piston in the working cylinder cannot move to the magnetic switch position, or if the piston disengages from the bottom of the cylinder during the operation of the robot arm, causing the magnetic switch signal to be lost, the PLC will not issue a motor power-on command or brake the motor and will issue an alarm. It is determined that the robot arm transfer component is interfered with by external force, resulting in excessive transmission resistance. The transmission system is protected by stopping the power source.

[0023] Step 2.3: After the servo motor is successfully powered on, the robotic arm transmission system is connected. The transmission components are controlled by the power station: the power component drives the moving slide, the moving slide drives the working cylinder, and the working cylinder drives the cylindrical rack to perform lateral reciprocating motion. At this time, the rack limit block at the end of the cylindrical rack slides laterally back and forth in the parallel groove of the stroke limit frame. The stroke limit frame is dragged to the maximum displacement stroke by the rack limit block and then stops. Only the rack limit block in the parallel groove continues to slide laterally repeatedly. Its sliding stroke is limited to the length of the parallel groove of the stroke limit frame.

[0024] As a further improvement to the present invention, the specific content of step 3 is as follows.

[0025] Step 3.1: When the robot's safety circuit is triggered or de-energized, both the robot's external power supply and air supply are cut off.

[0026] Step 3.2: The cylinder reversing valve is de-energized, and the valve core is reset to the normal position by the spring force. The air source at the working cylinder port A is cut off, so that the piston rod can be dragged by external force.

[0027] Step 3.3: Air enters through port A of the safety cylinder. The gas pushes the piston of the safety cylinder to move towards the bottom of the cylinder. As the stroke limit bracket is rapidly pulled back by the piston rod of the safety cylinder, the inner wall of its parallel groove will adhere to the rack limit block and be pulled back together. The rack limit block will drive the cylindrical rack to be rapidly pulled back together until the root of the stroke limit bracket abuts against the polyurethane block installed above the anti-collision frame. It will be slowly pulled back until the piston in the safety cylinder stops moving. That is, the cylindrical rack drives the arm seat to drive the robot arm transfer rod to retract to the safe position. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the main power station structure of the present invention.

[0029] Figure 2 This is a schematic diagram of the auxiliary power station structure of the present invention.

[0030] Figure 3 This is a schematic diagram showing the connection between the main power station and the auxiliary power station of the present invention.

[0031] Figure 4 This is a schematic diagram showing the connection between the robotic arm transfer component and the transmission component of the present invention.

[0032] Figure 5 This is a schematic diagram of the gas path system of the present invention.

[0033] The components include: 1. Servo motor; 2. Power unit base; 3. Reducer; 4. Moving slide; 5. Longitudinal fixing plate; 6. Magnetic switch; 7. Rod connecting block; 8. Second load-bearing frame; 9. Cylinder rear fixing plate; 10. Cylinder front fixing plate; 11. Anti-collision frame; 12. Polyurethane block; 13. Stroke limit frame; 21. Rack connecting block; 22. Column rack; 23. Rack limit block; 24. Arm seat; 25. Transfer rod; 31. Switch valve; 32. Triple unit; 33. Safety valve; 34. Check valve; 35. Air tank; 36. Pressure relief valve; 37. Pressure switch; 38. Cylinder reversing valve; 39. Quick exhaust valve; 40. Safety cylinder; 41. Working cylinder. Detailed Implementation

[0034] The present invention will be further described below with reference to the accompanying drawings:

[0035] like Figure 1-5 The illustrated robotic arm transmission protection device includes an active power station and an auxiliary power station. The active power station is connected to the auxiliary power station via a transmission assembly. Both the active power station and the auxiliary power station are connected to a pneumatic system. The transmission assembly is connected to the robotic arm base 24.

[0036] The main power station includes a first load-bearing frame, which is horizontally fixed to the ground. A power unit base 2 is vertically mounted on the first load-bearing frame, and a power component is vertically mounted on the power unit base 2. The power component includes a servo motor 1, which is connected to a reducer 3. The reducer 3 meshes with a rack at the bottom of a movable slide 4 via gears. The movable slide 4 can be driven by the power component to move laterally. A longitudinal fixing plate 5 is provided at the end of the movable slide 4, and a working cylinder 41 is mounted on the longitudinal fixing plate 5. The working cylinder 41 is parallel to the end of the movable slide 4. The working cylinder 41 is a double-acting cylinder. The front end of the piston rod of the working cylinder 41 is connected to a rod connecting block 7. A magnetic switch 6 is provided at the bottom of the working cylinder 41.

[0037] The auxiliary power station includes a second support frame 8, which is placed horizontally on the ground and horizontally fixed to the punch press column. A cylinder rear fixing plate 9 and a cylinder front fixing plate 10 are provided on the second support frame 8. A safety cylinder 40 is provided between the cylinder rear fixing plate 9 and the cylinder front fixing plate 10. The safety cylinder 40 is a double-acting cylinder, and the front end of the piston rod of the safety cylinder 40 is connected to the stroke limit frame 13.

[0038] The travel limit frame 13 has a U-shaped structure with hollow parallel grooves machined on both sides. The length of the hollow parallel grooves matches the transfer stroke of the robot arm. A collision protection frame 11 is installed on the second load-bearing frame 8. The collision protection frame 11 is installed directly below the end of the hollow parallel groove of the travel limit frame 13, with a gap at the top. A polyurethane block 12 is installed in the groove on the back of the collision protection frame 11.

[0039] The transmission assembly includes a cylindrical rack 22, the front end of which is connected to a rack connecting block 21. A threaded hole is opened in the shaft at the end of the cylindrical rack 22. A rack limiting block 23 is locked to the end of the cylindrical rack 22 by bolts. The working cylinder 41 and the safety cylinder 40 are concentric. The rack connecting block 21 is fixedly connected to the rod connecting block 7. The rack limiting block 23 is installed and limited in the hollow parallel groove of the stroke limiting frame 13, with both ends extending out of the hollow parallel groove. The cylindrical rack 22 meshes with the eccentric gear in the arm seat 24. The cylindrical rack 22 is connected to several arm seats 24 in sequence through the rack connecting block 21. The transfer rod 25 is placed horizontally on the transverse rolling bearing in the arm seat 24 and can slide laterally in the arm seat 24. The arm seat 24 is provided with a longitudinal rolling bearing that abuts against the transfer rod 25.

[0040] The pneumatic system includes a switching valve 31, which is connected to the air source in the plant and then to a triplet 32. The triplet 32 ​​is connected to a safety valve 33, which is connected to a check valve 34. The check valve 34 is connected to an air tank 35. The air tank 35 is equipped with a pressure relief valve 36 and a pressure switch 37. The air tank 35 is connected to a cylinder reversing valve 38, which is a two-position five-way single-control valve. The air inlet P of the cylinder reversing valve 38 is connected to the air tank 35, and the air outlet B of the cylinder reversing valve 38 is connected to the A port of the safety cylinder 40. The air outlet A of the cylinder reversing valve 38 is connected in series with a quick exhaust valve 39 and then connected to the A port of the working cylinder 41.

[0041] A method for protecting the transmission of a robotic arm includes the following steps:

[0042] Step 1, pneumatic system preparation;

[0043] When the robotic arm starts production, after the switch valve 31 is opened, the gas flows through the triplet 32 ​​to the safety valve 33. After the PLC checks that the safety circuit is closed, it powers on the safety valve 33. The gas flows into the gas storage tank 35 at a set flow rate. When the pressure in the gas storage tank 35 reaches the value of the pressure switch 37 valve 31, it sends a signal to the PLC. The PLC controls the cylinder reversing valve 38 to be energized, and the working cylinder 41 port A is filled with air. The air source of the safety cylinder 40 port A is cut off. The gas flowing into the working cylinder 41 pushes the piston to move to the bottom of the cylinder. At the same time, the piston rod pulls the cylindrical rack 22 to move to the right. The rack limit block 23 installed at the end of the cylindrical rack 22 moves to the right until it touches and drags the stroke limit frame 13.

[0044] Step 2: The main power station interacts with the auxiliary power station via the transmission components;

[0045] Step 2.1: When the magnetic switch 6 of the working cylinder 41 detects that the piston has moved to the bottom of the cylinder, the magnetic switch 6 will send a signal to the PLC. The PLC determines that the switching of the two cylinders is complete, controls the servo motor 1 to power on, and then issues an action command.

[0046] Step 2.2: If the piston in the working cylinder 41 cannot move to the position of the magnetic switch 6, or if the piston disengages from the bottom of the cylinder during the operation of the robot arm, causing the signal of the magnetic switch 6 to be lost, the PLC will not issue a motor power-on command or brake the motor and issue an alarm. It is determined that the robot arm transfer component is interfered with by external force, resulting in excessive transmission resistance. The transmission system is protected by stopping the power source.

[0047] Step 2.3: After the servo motor 1 is successfully powered on, the robotic arm transmission system is connected and the transmission components are controlled by the power station: the power component drives the movable slide 4, the movable slide 4 drives the working cylinder 41, and the working cylinder 41 drives the cylindrical rack 22 to perform lateral reciprocating motion. At this time, the rack limit block 23 at the end of the cylindrical rack 22 slides laterally and reciprocally in the parallel groove of the stroke limit frame 13. The stroke limit frame 13 is dragged to the maximum displacement stroke by the rack limit block 23 and then stops. Only the rack limit block 23 in the parallel groove continues to slide laterally repeatedly. Its sliding stroke is limited to the length of the parallel groove of the stroke limit frame 13.

[0048] Step 3, safety transmission protection.

[0049] Step 3.1: When the robot's safety circuit is triggered or de-energized, both the robot's external power supply and air supply are cut off.

[0050] Step 3.2: The cylinder reversing valve 38 is de-energized, and the valve core is reset to the normal position by the spring force. The air source at port A of the working cylinder 41 is cut off, so that the piston rod can be dragged by external force.

[0051] Step 3.3: Air enters through port A of safety cylinder 40. The gas pushes the piston of safety cylinder 40 to move towards the bottom of the cylinder. During the process of the stroke limit frame 13 being quickly pulled back by the piston rod of safety cylinder 40, the inner wall of its parallel groove will adhere to the rack limit block 23 and be pulled back together. The rack limit block 23 drives the cylindrical rack 22 to be quickly pulled back together until the root of the stroke limit frame 13 abuts against the polyurethane block 12 installed above the anti-collision frame 11. It is slowly pulled back until the piston in safety cylinder 40 stops moving. That is, the cylindrical rack 22 drives the arm seat 24 to drive the robot arm transfer rod 25 to retract to the safe position.

[0052] In this invention, the first load-bearing frame is horizontally fixed to the ground, the power unit base 2 is vertically installed on the first load-bearing frame, the power assembly is vertically installed on the power unit base 2, the power assembly is meshed with the bottom of the movable slide 4 through a gear and rack, the movable slide 4 can be driven by the power assembly to move laterally, the working cylinder 41 is vertically fixed to the longitudinal fixing plate 5 by bolts and installed parallel to the end of the movable slide 4, the working cylinder 41 is defined as a double-acting cylinder, the piston rod front end has an external thread, which is screwed into the rod connecting block 7 through the thread, the bottom of the working cylinder 41 is provided with a longitudinal fixing plate 5 to detect the position of the piston inside the cylinder.

[0053] The second support frame 8 is placed horizontally on the ground and fixed laterally to the punch press column. The cylinder rear fixing plate 9 and the cylinder front fixing plate 10 horizontally fix the safety cylinder 40 on the second support frame 8. The safety cylinder 40 is a double-acting cylinder with an external thread at the front end of the piston rod. The stroke limit frame 13 is screwed onto the front end of the cylinder piston rod by the thread. The stroke limit frame 13 has a U-shaped structure with open sides. The length of the open parallel groove is limited according to the transfer stroke of the robot arm. The anti-collision frame 11 is fixed on the second support frame 8 and is installed directly below the end of the parallel groove of the stroke limit frame 13, with a certain gap at the top. The polyurethane block 12 is placed in the groove on the back of the anti-collision frame 11 as a buffer. The stroke limit frame 13 moves laterally within the stroke of the safety cylinder 40, following the extension and retraction of the piston rod, and is equipped with a buffer.

[0054] The front end of the cylindrical rack 22 has an external thread that engages with the rack connecting block 21. The end of the cylindrical rack 22 has a threaded hole. The rack limiting block 23 is locked to the end of the cylindrical rack 22 by bolts. The arm seat 24 is one of the components of the robotic arm and is a cam device that is horizontally fixed to the punch press table. The arm 24 has an eccentric gear that meshes with the cylindrical rack 22. The cylindrical rack 22 is connected to several arm seats 24 in sequence through the rack connecting block 21 to form a transmission device group. The transfer rod 25 is horizontally placed on the transverse rolling bearing in the arm seat 24 and can slide laterally in the arm seat 24. The arm seat 24 has a longitudinal rolling bearing to hold the transfer rod 25 in place. The transfer rod 25 is made to reciprocate longitudinally in the longitudinal arm seat 24 by driving the cylindrical rack 22 at the working cylinder 41.

[0055] The shafts of the working cylinder 41 and the safety cylinder 40 of the auxiliary power station must be concentric. The rack connecting block 21 of the transmission component is fixed to the rod connecting block 7 of the main power station by bolts. The rack limiting block 23 of the transmission component is installed and restricted in the parallel groove of the stroke limiting frame 13. Its length is slightly longer than the width of the stroke limiting frame 13, and it can move laterally back and forth.

[0056] After the switching valve 31 is connected to the plant's air source, it is connected in series with a triplet 32, a safety valve 33, a check valve 34, and an air tank 35. The air tank 35 is equipped with a pressure relief valve 36 and a pressure switch 37 to ensure system pressure. The cylinder reversing valve 38 is limited to a two-position five-way single-control valve. The air source for the air inlet P is connected to the air tank 35. The air outlet B of the cylinder reversing valve 38 is connected to the port A of the safety cylinder 40. The air outlet A of the cylinder reversing valve 38 is connected in series with a quick exhaust valve 39 and then connected to the port A of the working cylinder 41.

[0057] During operation, the robotic arm starts production. When the switch valve 31 is opened, the gas flows through the triplet 32 ​​to the safety valve 33. After the PLC checks that the safety circuit is closed, it powers on the safety valve 33. The gas flows into the gas storage tank 35 at a set flow rate. When the pressure in the gas storage tank 35 reaches the value of the pressure switch 37 valve 31, it sends a signal to the PLC. The PLC controls the cylinder reversing valve 38 to be energized, and the working cylinder 41 port A is filled with air. The air source of the safety cylinder 40 port A is cut off. The gas flowing into the working cylinder 41 pushes the piston to move to the bottom of the cylinder. At the same time, the piston rod pulls the cylindrical rack 22 to move to the right. The rack limit block 23 installed at the end of the cylindrical rack 22 moves to the right until it abuts and drags the stroke limit frame 13.

[0058] When the magnetic switch 6 of the working cylinder 41 detects that the piston has moved to the bottom of the cylinder, the magnetic switch 6 will send a signal to the PLC. The PLC determines that the switching of the two cylinders is complete, controls the servo motor 1 to be powered on, and then issues an action command. If the piston in the working cylinder 41 cannot move to the position of the magnetic switch 6, or if the piston disengages from the bottom of the cylinder during the operation of the robot, causing the signal of the magnetic switch 6 to be lost, the PLC will not issue a motor power-on command or brake the motor and will issue an alarm. It is determined that the robot's transfer component is subject to external interference, resulting in excessive transmission resistance. The PLC will then stop the power source to protect the transmission system.

[0059] After the servo motor 1 is successfully powered on, the transmission system of the robotic arm is connected and the transmission components are controlled by the power station: the power component drives the movable slide 4, the movable slide 4 drives the working cylinder 41, and the working cylinder 41 drives the cylindrical rack 22 to perform lateral reciprocating motion. At this time, the rack limit block 23 at the end of the cylindrical rack 22 slides laterally and reciprocatingly in the parallel groove of the stroke limit frame 13. The stroke limit frame 13 is dragged to the maximum displacement stroke by the rack limit block 23 and then stops to reduce transmission resistance. Only the rack limit block 23 in the parallel groove continues to slide laterally repeatedly, and its sliding stroke is limited to the length of the parallel groove of the stroke limit frame 13.

[0060] In practical applications, each cylindrical rack 22 is driven by the arm seat 24 through gear and rack meshing, so that the transfer rod 25 of the robot can move longitudinally under the action of the working cylinder 41, and can be connected sequentially to the cylindrical racks 22 of several arm seats 24 through the rack connecting block 21 to form a linear transmission device group to realize multi-station transmission.

[0061] When the safety circuit of the robot arm is triggered or de-energized, the external power supply and air supply of the robot arm are cut off. Since the air tank 35 is equipped with a one-way valve 34 at the inlet, the gas will not be discharged quickly through the safety valve 33. The stored gas can ensure the switching of the two cylinders. When the cylinder reversing valve 38 is de-energized, the valve core is reset to the normal position by the spring force. The air supply of port A of the working cylinder 41 is cut off. The piston rod can be dragged by external force. That is, the power source of the transmission component and the power station is cut off and is not affected by the braking or inertia of the power component.

[0062] Air enters through port A of safety cylinder 40, pushing the piston of safety cylinder 40 towards the bottom of the cylinder. At this point, regardless of the position of the rack limit block 23, because the stroke limit bracket 13 has limited its maximum reciprocating stroke, the inner wall of the parallel groove of the stroke limit bracket 13 will adhere to the rack limit block 23 and be pulled back together during the rapid retraction process by the piston rod of safety cylinder 40. Since the rack limit block 23 is fixed to the end of the cylindrical rack 22, the rack limit block 23 and the cylindrical rack 22 are thus rapidly pulled back together until the stroke... The base of the limit bracket 13 abuts against the polyurethane block 12 installed above the anti-collision bracket 11 to reduce the impact force. It is slowly pulled back until the piston in the safety cylinder 40 stops moving. That is, the cylindrical rack 22 drives the arm seat 24 to drive the robotic arm transfer rod 25 to retract to the safe position. In this emergency, the transmission component is disconnected from the power source of the main power station. Affected by the auxiliary power station, the safety cylinder 40 drives the transmission component, which drives the peripheral transfer component to retract to the safe position, avoiding the occurrence of safety accidents such as collisions and improving the safety level of the equipment.

[0063] This invention utilizes a controllable cylinder reversing device to quickly and safely connect or disconnect the robot's transmission components from the power source, ensuring high-precision transmission while preventing safety accidents. This device has a compact structure, high reliability, and can effectively reduce the failure rate of robot equipment, improve safety levels, and enhance the equipment's market competitiveness.

[0064] This invention is not limited to the above embodiments. Based on the technical solutions disclosed herein, those skilled in the art can make some substitutions and modifications to some of the technical features without creative effort, and all such substitutions and modifications are within the protection scope of this invention.

Claims

1. A protective device for the transmission of a robotic arm, characterized in that, It includes a main power station, which is matched with an auxiliary power station. The main power station is connected to the auxiliary power station via a transmission component. Both the main power station and the auxiliary power station are connected to the pneumatic system. The transmission component is connected to the arm base of the robotic arm. The main power station includes a first load-bearing frame, which is horizontally fixed to the ground. A power unit base is vertically mounted on the first load-bearing frame, and a power component is vertically mounted on the power unit base. The power component includes a servo motor, which is connected to a reducer. The reducer meshes with a rack at the bottom of the movable slide via gears. The movable slide can be driven by the power component to move laterally. A longitudinal fixing plate is provided at the end of the movable slide, and a working cylinder is mounted on the longitudinal fixing plate. The working cylinder is parallel to the end of the movable slide and is a double-acting cylinder. The front end of the piston rod of the working cylinder is connected to a rod connecting block, and a magnetic switch is provided at the bottom of the working cylinder. The auxiliary power station includes a second support frame, which is placed horizontally on the ground and horizontally fixed to the punch press column. The second support frame is equipped with a cylinder rear fixing plate and a cylinder front fixing plate. A safety cylinder is installed between the cylinder rear fixing plate and the cylinder front fixing plate. The safety cylinder is a double-acting cylinder, and the front end of the piston rod of the safety cylinder is connected to the stroke limit frame. The travel limit frame has a U-shaped structure with hollow parallel grooves machined on both sides. The length of the hollow parallel grooves matches the transfer stroke of the robot arm. A collision protection frame is installed on the second load-bearing frame. The collision protection frame is installed directly below the end of the hollow parallel groove of the travel limit frame, with a gap at the top. A polyurethane block is installed in the groove on the back of the collision protection frame. The transmission assembly includes a cylindrical rack, the front end of which is connected to a rack connecting block, and a threaded hole in the shaft at the end of the cylindrical rack. A rack limiting block is locked to the end of the cylindrical rack by bolts. The working cylinder and the safety cylinder are concentric. The rack connecting block is fixedly connected to the rod connecting block. The rack limiting block is installed and restricted in the hollow parallel groove of the stroke limiting frame, with both ends extending out of the hollow parallel groove. The cylindrical rack meshes with an eccentric gear in the arm seat. The cylindrical rack is connected to several arm seats in sequence through the rack connecting block. The transfer rod is placed horizontally on a transverse rolling bearing in the arm seat and can slide laterally in the arm seat. A longitudinal rolling bearing is provided in the arm seat, which abuts against the transfer rod. The pneumatic system includes a switching valve, which is connected to the air supply in the plant and then to a triplet unit. The triplet unit is connected to a safety valve, which is connected to a check valve. The check valve is connected to an air tank, which is equipped with a pressure relief valve and a pressure switch. The air tank is connected to a cylinder reversing valve, which is a two-position five-way single-control valve. The air inlet P of the cylinder reversing valve is connected to the air tank, and the air outlet B of the cylinder reversing valve is connected to the safety cylinder port A. The air outlet A of the cylinder reversing valve is connected in series with a quick exhaust valve and then connected to the working cylinder port A.

2. A method for protecting the transmission of a robotic arm, characterized in that: Includes the following steps, Step 1, pneumatic system preparation; When the robotic arm starts production, after the switch valve is opened, the gas flows through the triplet to the safety valve. After the PLC checks that the safety circuit is closed, it powers on the safety valve. The gas flows into the gas tank at a set flow rate. When the pressure in the gas tank reaches the pressure switch threshold, it sends a signal back to the PLC. The PLC controls the cylinder reversing valve to be energized, and the working cylinder port A is filled with air. The air supply to the safety cylinder port A is cut off. The gas flowing into the working cylinder pushes the piston to move to the bottom of the cylinder. At the same time, the piston rod pulls the cylindrical rack to move to the right. The rack limit block installed at the end of the cylindrical rack moves to the right until it touches and drags the stroke limit frame. Step 2: The main power station interacts with the auxiliary power station via the transmission components; Step 2.1: When the magnetic switch of the working cylinder detects that the piston has moved to the bottom of the cylinder, the magnetic switch will send a signal to the PLC. The PLC determines that the switching of the two cylinders is complete, controls the servo motor to power on, and then issues an action command. Step 2.2: If the piston in the working cylinder cannot move to the magnetic switch position, or if the piston disengages from the bottom of the cylinder during the operation of the robot arm, causing the magnetic switch signal to be lost, the PLC will not issue a motor power-on command or brake the motor and will issue an alarm. It is determined that the robot arm transfer component is interfered with by external force, resulting in excessive transmission resistance. The transmission system is protected by stopping the power source. Step 2.3: After the servo motor is successfully powered on, the robot's transmission system is connected. The transmission components are controlled by the power station: the power component drives the moving slide, the moving slide drives the working cylinder, and the working cylinder drives the cylindrical rack to perform lateral reciprocating motion. At this time, the rack limit block at the end of the cylindrical rack slides laterally back and forth in the parallel groove of the stroke limit frame. The stroke limit frame is dragged to the maximum displacement stroke by the rack limit block and then stops. Only the rack limit block in the parallel groove continues to slide laterally repeatedly. Its sliding stroke is limited to the length of the parallel groove of the stroke limit frame. Step 3, safety transmission protection; Step 3.1: When the robot's safety circuit is triggered or de-energized, both the robot's external power supply and air supply are cut off. Step 3.2: The cylinder reversing valve is de-energized, and the valve core is reset to the normal position by the spring force. The air source at the working cylinder port A is cut off, so that the piston rod can be dragged by external force. Step 3.3: Air enters through port A of the safety cylinder. The gas pushes the piston of the safety cylinder to move towards the bottom of the cylinder. As the stroke limit bracket is rapidly pulled back by the piston rod of the safety cylinder, the inner wall of its parallel groove will adhere to the rack limit block and be pulled back together. The rack limit block will drive the cylindrical rack to be rapidly pulled back together until the root of the stroke limit bracket abuts against the polyurethane block installed above the anti-collision frame. It will be slowly pulled back until the piston in the safety cylinder stops moving. That is, the cylindrical rack drives the arm seat to drive the robot arm transfer rod to retract to the safe position.

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