Safety protection system and method for pusher chain device test bench

Abstract

The present application relates to push chain device test bench technical field, specifically to a kind of push chain device test bench safety protection system and method, system includes push chain device test bench and safety protection system;The safety protection system includes programmable controller, position sensor, tension and pressure sensor and limit switch.The present application is based on a kind of multi-dimension software and hardware combined safety protection system, judges the trigger condition of safety protection from 4 dimensions, judges and realizes the all-round protection of push chain device test bench in combination with software algorithm and hardware circuit control, to extend the service life of push chain device test bench.

Description

Technical Field

[0001] This invention relates to the field of test bench technology for push chain devices, and specifically to a safety protection system and method for a test bench for push chain devices. Background Technology

[0002] Push chain conveyors are widely used in logistics transportation and automated assembly lines due to their high load-bearing capacity, precise positioning control, and compact structure. Most push chain conveyors are used in heavy-load applications, requiring positioning accuracy tests, load-bearing capacity tests, and fatigue tests to obtain reliable performance parameters. Given the high stroke and heavy load characteristics of push chain conveyors, the safety protection system of the test bench is crucial. Comprehensive safety protection can prevent damage to the test bench, extend its service life, and improve its economic efficiency. However, current technologies lack solutions for such safety protection. Summary of the Invention

[0003] This invention provides a safety protection system and method for a push chain device test bench. Based on a multi-dimensional software and hardware combined safety protection system, it judges the trigger conditions for safety protection from four dimensions. By combining software algorithm judgment and hardware circuit control, it realizes all-round protection of the push chain device test bench, thereby extending the service life of the push chain device test bench.

[0004] To achieve the above objectives, the technical solution of the present invention is as follows:

[0005] A safety protection system for a push chain device test bench includes a push chain device test bench and a safety protection system. The push chain device test bench includes four longitudinally arranged columns in a rectangular pattern. Guide rails are provided on the inner sides of each of the four columns. A lifting platform is slidably connected along the four guide rails. A push chain device mounting platform is fixedly installed on the inner side of the four columns below the lifting platform. A push chain device is mounted on the mounting platform. The push chain head output by the push chain device extends longitudinally upward and is fixedly connected to the center of the bottom of the lifting platform. The push chain device is driven by a drive mechanism to move the lifting platform up and down. The safety protection system includes a programmable controller, a position sensor, a tension / compression sensor, and a limit switch.

[0006] Preferably, the four columns are provided with protective netting on their outer sides, and the drive mechanism includes a three-phase asynchronous motor, which is connected to the drive shaft of the push chain device via a universal coupling.

[0007] Preferably, the position sensor is installed at the tail of the output shaft of the three-phase asynchronous motor to detect the number of rotations of the output shaft and to provide the programmable controller with the real-time position of the push chain head; the tension and compression sensor is installed between the push chain head and the lifting platform to detect the load on the push chain; the limit switch includes an upper limit switch and a lower limit switch, which are respectively installed on the column to detect the highest and lowest heights of the lifting platform.

[0008] A control method for a safety protection system of a push chain device test bench, including software protection methods:

[0009] (1) The real-time position Pr of the push chain head is detected by the position sensor, the output torque Mr of the three-phase asynchronous motor is detected by the frequency converter, and the push chain thrust Fr is detected by the tension and compression sensor.

[0010] (2) Through a timer interrupt program, the position Pi of the position sensor is read at intervals T (seconds), and the position is calculated according to the velocity formula. Calculate the speed Vr of the push chain device;

[0011] (3) The first layer of safety protection is to determine whether the safety protection detection value S1 of the push chain device is equal to the set threshold S. 10 Relationship: Based on the motor torque coefficient during the operation of the push chain device Speed ​​coefficient of push chain device Push chain device thrust coefficient Compare and judge these 3 sets of coefficients to obtain the first level of security protection detection value: S1 = Max{M1; V1; F1}, when the first level of security protection detection value S1 ≥ S 10 When this occurs, the programmable controller output Q1.3, i.e., safety protection output one, is triggered, the test bench immediately stops running, and the brake of the three-phase asynchronous motor loses power;

[0012] (4) The second layer of safety protection is to determine whether the safety protection detection value S2 of the push chain device is equal to the set threshold S. 20 Relationship: Based on the real-time position P of the push chain device head r The lower limit P of the push chain device head position r1 and position upper limit P r2 Compare and judge these three values ​​to obtain the second layer of security protection detection value S2 = Max{P r ≥P2; P r ≤P r1 When the second layer of security protection detection value S2 ≥ S 20 When the circuit is activated, the programmable controller output Q1.4, i.e., safety protection output two, is triggered, and the test bench immediately stops running and the brake is de-energized.

[0013] Preferably, hardware protection is also included, specifically: A safety protection output one controls the coil of the first auxiliary relay, and the two normally closed contacts of the first auxiliary relay control the first safety relay; when safety protection output one is triggered, the two normally closed contacts of the first auxiliary relay are disconnected, thus disconnecting the input channel of the first safety relay. The programmable controller immediately cuts off the inverter's operating signal, the three-phase asynchronous motor stops running, the brake loses power, and the test bench stops; A safety protection output two controls the coil of the second auxiliary relay, and the two normally closed contacts of the second auxiliary relay control the second safety relay. When safety protection output two is triggered, the two normally closed contacts of the second auxiliary relay are disconnected, thus disconnecting the input channel of the second safety relay. The programmable controller detects that the output signal of the second safety relay is disconnected and immediately cuts off the control power supply of the inverter and the brake power supply, causing the three-phase asynchronous motor to stop running and the test bench to stop, thus achieving safety protection.

[0014] The safety protection system and method for a push chain device test bench of the present invention have the following beneficial effects:

[0015] (1) This safety protection system is designed with multiple safety factors, including the position, speed, thrust and drive motor torque of the push chain device, and multiple safety loops are formed by using multiple parameters, so that the protection is more comprehensive.

[0016] (2) This safety protection system uses software to set safety thresholds, which is flexible and convenient for operators to modify.

[0017] (3) This safety protection system adopts a combination of software algorithm safety output and hardware circuit. When the safety protection is triggered, the alarm can only be cleared after the alarm is triggered and the system is manually reset, which improves the safety protection level of the push chain device test bench.

[0018] (4) After the safety circuit of this safety protection system is disconnected, it must be manually reset before the test bench can be restarted to prevent secondary damage caused by misoperation.

[0019] (5) The dual hardware loop design greatly improves the safety level of the push chain device test bench.

[0020] (6) The safety circuit is controlled by a double contact, which avoids the failure of the safety control circuit due to contact sticking and improves the safety factor.

[0021] (7) Adopting a safety circuit design that combines hardware and software, it achieves more reliable protection with flexible adjustment.

[0022] (8) It can realize unmanned operation of the push chain device test bench, reducing maintenance costs. Attached Figure Description

[0023] Figure 1 For safety control flowchart;

[0024] Figure 2 Three-dimensional structure of the push chain device test bench Figure 1 ;

[0025] Figure 3 Three-dimensional structure of the push chain device test bench Figure 2 ;

[0026] Figure 4 This is the schematic diagram of safety circuit one;

[0027] Figure 5 This is the schematic diagram of safety circuit two.

[0028] The markings in the diagram are: 1. Column; 2. Adjustable limit switch bracket; 3. Lifting platform; 4. Guide rail; 5. Photoelectric sensor; 6. Push chain device mounting platform; 7. Adjustable push chain device mounting base; 8. Tension / compression sensor; 9. Push chain device; 10. Lower limit switch; 11. Motor base; 12. Three-phase asynchronous motor; 13. Position sensor; 14. Motor flange sleeve; 15. Universal coupling; 16. Push chain device flange sleeve; 17. Upper limit switch. Detailed Implementation

[0029] The following description provides a detailed explanation of the embodiments of the present invention in a step-by-step manner. This description is only a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0030] In the description of this invention, it should be noted that the terms "upper," "lower," "left," "right," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or a specific orientational structure and operation. Therefore, they should not be construed as limiting this invention.

[0031] Example 1: A safety protection system for a test bench of a push chain device, such as Figure 2 , 3As shown, the device includes a push chain device test bench and a safety protection system. The push chain device test bench includes four longitudinally arranged rectangular columns 1. Each of the four columns 1 has a guide rail 4 on its inner side. A lifting platform 3 is slidably connected along the four guide rails 4. A push chain device mounting platform 6 is fixedly installed on the inner side of the four columns 1 below the lifting platform 3. A push chain device 9 is installed on the push chain device mounting platform 6. The push chain head output by the push chain device extends longitudinally upward and is fixedly connected to the center of the bottom of the lifting platform 3. The push chain device is driven by a drive mechanism to move the lifting platform 3 up and down. The safety protection system includes a programmable controller, a position sensor 13, a tension / compression sensor 8, and a limit switch 10.

[0032] like Figure 2 , 3 As shown, the four columns 1 are equipped with protective netting (a common structure, not shown in the figure). The drive mechanism includes a three-phase asynchronous motor 12, which is connected to the drive shaft of the push chain device 9 via a universal coupling 15. The push chain device is existing technology, consisting of two interlocking chains forming a push chain, driven by a motor connected to the drive shaft. When the chains are output, they mesh together to form a rigid structure.

[0033] like Figure 3 As shown, the position sensor 13 is installed at the tail of the output shaft of the three-phase asynchronous motor 12 to detect the number of rotations of the output shaft and to provide the programmable controller with the real-time position of the push chain head; the tension and compression sensor 8 is installed between the push chain head and the lifting platform 3 and is used to detect the load of the push chain (i.e., the thrust of the push chain); the limit switch includes an upper limit switch and a lower limit switch, the lower limit switch 10 is installed on the column to detect the minimum height of the lifting platform 3; the upper limit switch 17 is installed on the column to detect the maximum height of the lifting platform 3.

[0034] Example 2: Based on Example 1, this example discloses a control method for a safety protection system of a push chain device test bench, including software protection methods:

[0035] (1) The real-time position Pr of the push chain head is detected by the position sensor, the output torque Mr of the three-phase asynchronous motor is detected by the frequency converter, and the push chain thrust Fr is detected by the tension and compression sensor.

[0036] (2) Through a timer interrupt program, the position Pi of the position sensor is read at intervals T (seconds), and the position is calculated according to the velocity formula. Calculate the speed Vr of the push chain device;

[0037] (3) The first layer of safety protection is to determine whether the safety protection detection value S1 of the push chain device is equal to the set threshold S. 10 Relationship: Based on the motor torque coefficient during the operation of the push chain device Speed ​​coefficient of push chain device Push chain device thrust coefficient Compare and judge these three sets of coefficients to obtain the first level of security protection detection value: S1 = Max{M1; V1; F1}, when the first level of security protection detection value S1 ≥ S 10 When this occurs, the programmable controller output Q1.3, i.e., safety protection output one, is triggered, the test bench immediately stops running, and the brake of the three-phase asynchronous motor is de-energized; see also Figure 4 Schematic diagram of safety circuit 1.

[0038] (4) The second layer of safety protection is to determine whether the safety protection detection value S2 of the push chain device is equal to the set threshold S. 20 Relationship: Based on the real-time position P of the push chain device head r The lower limit P of the push chain device head position r1 and position upper limit P r2 Compare and judge these three values ​​to obtain the second layer of security protection detection value S2 = Max{P r ≥P r2 ;P r ≤P r1 When the second layer of security protection detection value S2 ≥ S 20 When this occurs, the programmable controller output Q1.4, i.e., safety protection output two, is triggered, the test bench immediately stops running, and the brake is de-energized. See [link / reference]. Figure 5 Schematic diagram of safety circuit two.

[0039] Example 3: This also includes hardware protection, specifically: a safety protection output is set to control the coil of the first auxiliary relay R11351. The two normally closed contacts 11-12 and 21-22 of the first auxiliary relay R11351 control the first safety relay K11351. When the safety protection output is triggered, the two normally closed contacts of the first auxiliary relay R11351 are disconnected, and the input channel of the first safety relay K11351 is also disconnected. The programmable controller immediately cuts off the inverter's operating signal, the three-phase asynchronous motor stops running, the brake loses power, and the test bench stops. This safety protection... The second safety protection output controls the coil of the second auxiliary relay R11361. The two normally closed contacts 11-12 and 21-22 of the second auxiliary relay R11361 control the second safety relay K11361. When the second safety protection output is triggered, it cuts off the two sets of normally closed contacts of the second auxiliary relay R11361, and also cuts off the input channel of the second safety relay K11361. The programmable controller detects that the output signal of the second safety relay K11361 is disconnected, and immediately cuts off the control power supply of the frequency converter and the brake power supply. The three-phase asynchronous motor stops running, the test bench stops, and the safety protection is achieved.

Claims

1. A safety protection system for a push chain device test bench, characterized in that: it includes a push chain device test bench and a safety protection system; the push chain device test bench includes four longitudinally arranged columns in a rectangular pattern; each of the four columns has a guide rail on its inner side; a lifting platform is slidably connected along the four guide rails; a push chain device mounting platform is fixedly installed on the inner side of the four columns below the lifting platform; a push chain device is installed on the mounting platform; the push chain head output by the push chain device extends longitudinally upward and is fixedly connected to the center of the bottom of the lifting platform; the push chain device is driven by a drive mechanism to move the lifting platform up and down; the safety protection system includes a programmable controller, a position sensor, a tension / compression sensor, and a limit switch. The control methods of this security protection system include software protection methods: (1) The real-time position Pr of the push chain head is detected by the position sensor, the output torque Mr of the three-phase asynchronous motor is detected by the frequency converter, and the push chain thrust Fr is detected by the tension and compression sensor. (2) The position Pi of the position sensor is read at intervals T (seconds) by a timer interrupt program, and the position is calculated according to the velocity formula. Calculate the speed Vr of the push chain device; (3) The first layer of safety protection is to determine the safety protection detection value of the push chain device. With the set threshold S 10 Relationship: Based on the motor torque coefficient during the operation of the push chain device Speed ​​coefficient of push chain device Thrust coefficient of push chain device By comparing and judging these three sets of coefficients, the first level of security protection detection value is obtained: When the first layer of security protection detection value When this occurs, the programmable controller output Q1.3, i.e., safety protection output one, is triggered, the test bench immediately stops running, and the brake of the three-phase asynchronous motor loses power; (4) The second layer of safety protection is to determine the safety protection detection value of the push chain device. With set threshold Relationship: Based on the real-time position of the push chain device head Lower limit of the head position of the push chain device and position limit The second layer of security protection detection value is obtained by comparing and judging these three values. When the second layer of security protection detection value When this occurs, the programmable controller output Q1.4, i.e., safety protection output two, is triggered, the test bench immediately stops running, and the brake is de-energized; It also includes hardware protection methods, specifically: Safety protection output one controls the coil of the first auxiliary relay, and the two normally closed contacts of the first auxiliary relay control the first safety relay; when safety protection output one is triggered, it disconnects the two normally closed contacts of the first auxiliary relay, also disconnecting the input channel of the first safety relay. The programmable controller immediately cuts off the inverter's running signal, the three-phase asynchronous motor stops running, the brake loses power, and the test bench stops. Safety protection output two controls the coil of the second auxiliary relay, and the two normally closed contacts of the second auxiliary relay control the second safety relay. When safety protection output two is triggered, it disconnects the two normally closed contacts of the second auxiliary relay, also disconnecting the input channel of the second safety relay. The programmable controller detects the disconnection of the second safety relay's output signal and immediately cuts off the inverter's control power and the brake's power, causing the three-phase asynchronous motor to stop running and the test bench to stop, thus achieving safety protection.

2. The safety protection system of the push chain device test bench as described in claim 1, characterized in that: a protective net is provided on the outside of the four columns, and the drive mechanism includes a three-phase asynchronous motor, wherein the three-phase asynchronous motor is connected to the drive shaft of the push chain device through a universal coupling.

3. The safety protection system for a push chain device test bench as described in claim 2, characterized in that: The position sensor is installed at the tail of the output shaft of the three-phase asynchronous motor to detect the number of rotations of the output shaft and to provide the programmable controller with the real-time position of the push chain head; the tension and compression sensor is installed between the push chain head and the lifting platform to detect the load on the push chain; the limit switch includes an upper limit switch and a lower limit switch, which are respectively installed on the column to detect the minimum and maximum height of the lifting platform.

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