Automatic scanning device for two-dimensional code of indication ticket of automobile production line
By designing an automatic scanning device, the power of the production line boom is used to drive the connecting rod mechanism to automatically scan the QR code on the car body boom, which solves the problem of scanning time delay caused by manual scanning and improves production efficiency and the continuity of the assembly line.
Patent Information
- Application Number
- CN202510649633.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-20
- Publication Date
- 2025-09-05
AI Technical Summary
In the existing technology, manual handheld scanners on automobile production lines scan QR codes on vehicle body booms with unstable scanning distance and range, resulting in delayed scanning time, affecting production efficiency and the continuity of the assembly line.
An automatic scanning device was designed, which uses the force of the mobile boom of the production line to drive the connecting rod mechanism, and transmits power through the pull rope, so that the scanning mechanism automatically moves to the specified position and presses the scanner gun switch to complete the automatic scanning of the QR code.
It realizes automatic QR code scanning without manual operation, improves the stability and efficiency of scanning, reduces labor time waste, and improves the continuity and safety of the production line.
Smart Images
Figure CN120597910A_ABST
Abstract
Description
Technical Field
[0001] The invention discloses an automatic scanning device for a QR code of an instruction ticket on an automobile production line, which is used for automatically scanning instruction tickets on an automobile production line, and relates to the technical field of designing and manufacturing automatic scanning equipment for a QR code of an instruction ticket on an automobile production line. Background Art
[0002] To accurately understand the content and processes required for vehicle installation at each workstation on an automotive production line, existing technology accompanies the process with a technical content instruction sheet with a QR code. Currently, operators typically use dedicated scanning equipment, manually holding a scanner and walking up to the instruction sheet attached to the body boom on the assembly line to scan it. Operators then return to the workbench to obtain the required work tasks and process requirements from the monitor. These tasks include information such as component installation, fixtures, production batches, and process parameters. While industrial-grade barcode scanners or fixed scanners are currently used, some production lines also use OBD-II devices with integrated scanning functions, such as for equipment self-test and fault code reading scenarios. These devices have high-precision recognition capabilities and can adapt to the high-speed scanning needs of the production line. Some also connect scan data through MES (Manufacturing Execution System) or ERP systems to achieve real-time tracking of the production process.
[0003] However, with the development of the modern industrial automated production era, production companies are paying more and more attention to the health of their employees and production efficiency, and their pursuit of production efficiency is constantly improving. In order to achieve better production results, they often propose to find shortcomings, including effective savings, improving the human physical and mental health environment, and strengthening automation, as well as the degree of artificial intelligence production, to avoid waste caused by mistakes and other work requirements.
[0004] Currently, in the automobile manufacturing process, the component differentiation information of different models is recorded on an A3-sized production instruction sheet. In order to accurately implement the process requirements described on the instruction sheet, all work areas with requirements need to scan the QR code on the production instruction to accurately identify vehicle information and assembly requirements. However, on the earlier production lines, due to cost reasons, most QR code readers needed to use conventional scanners to scan the QR code on the instruction sheet. The operator needed to manually pick up the scanner and align it with the QR code on the instruction sheet pasted on the vehicle body boom, and then press the scanner switch to complete the scanning action. However, the body crane is a mobile tooling with a certain height, and the body crane also carries the vehicle that needs to be installed. Due to the different heights of operators, taller ones can scan the QR code more easily, while shorter ones need to stand on tiptoe to work. In addition, since the signal range of the scanner is limited, during operation, regardless of height, there will be a waste of time in the process of finding and scanning the QR code. When the body crane is in a moving state, if the scan cannot be completed for a long time, it will not be able to be well combined with other work positions, resulting in the stop of the assembly line.
[0005] Purpose of the present invention The purpose of the present invention is to solve the problem that the existing technology relies on manual handheld scanning guns to scan the QR code on the moving body hanger, resulting in delays in scanning time due to the instability and uncertainty of the scanning distance and scanning range, as well as extended working hours due to scanning delays. An automatic scanning device for the QR code of the automobile production line instruction ticket is designed, which can automatically scan the automobile production line instruction ticket along with the body hanger.
[0006] The present invention comprises a scanning structure, a wire drawing structure and a scanning mounting platform structure: The scanning structure is composed of a scanning gun sliding sleeve 8, a scanning gun cable pulley 9, a scanning gun cable anchor point 10, a scanning gun 11, a scanning gun travel switch rod 12, a scanning gun mounting frame 13, a scanning gun moving pulley 14, a mounting frame 15, a scanning gun mounting platform 16, and a scanning gun travel wheel 17; The scanning gun 11 is mounted on a scanning gun mounting base 25 , a scanning gun sliding track 28 is provided between the scanning gun 11 and the scanning gun mounting base 25 , and a scanning gun sliding sleeve 8 is provided on the scanning gun sliding track 28 ; A spring 31 is provided at the tail end of the scanner sliding sleeve 8. The spring 31 passes through a spring fulcrum 30 and is hung on a spring hanging arm 29. The spring fulcrum 30 forms a pulling force for the spring 31 to move the scanner sliding sleeve 8 backward. A scanner pressing finger 24 is provided at the front end of the scanner sliding sleeve 8, and a push-type switch 32 of the scanner 11 is provided between the scanner 11 and the scanner sliding rail 28, and the scanner pressing finger 24 is provided so as to face the push-type switch 32 of the scanner 11. Preferably, the push switch 32 of the scanner 11 is in a fixed position and does not move, and the scanner pressing finger 24 moves with the scanner sliding sleeve 8; A scanner wire steering pulley 9 is provided on the scanner mounting base 25, and the scanner wire 91 passes through the scanner wire steering pulley 9 and is anchored at the front end of the scanner sliding sleeve 8; Preferably, the scanning structure is mounted on a scanner mounting frame 13, and the scanner mounting frame 13 is mounted on a scanner mounting platform 16. One end of the scanner mounting platform 16 is connected to a scanner mounting platform cable 71, and the other end is fixedly connected to a scanner shift cable 7. The pull wire structure includes a scanning gun pull wire 91 and a scanning gun shift pull wire 71; The scanner cable 91 passes through the pulley 19, and the tail end is fixed to the scanner switch cable anchor point 18 set in the middle of the scanner travel switch rod 12. The upper end passes through the scanner cable turning pulley 9 and is anchored to the front end of the scanner sliding sleeve 8; The scanner mounting platform cable 71 passes through the pulley 61, the tail end is anchored to the counterweight 26, and the other end is connected to the rear end of the scanner mounting platform 16. The front end of the scanner mounting platform 16 is fixedly connected to the scanner shift cable 7. The scanner shift cable 7 passes through the third cable pulley 6, the second cable pulley 21, and the first cable pulley 22 and is fixed to the lower end of the toggle rod 23. The scanning mounting platform structure includes a mounting frame 15 for the scanning gun 11 and a toggle rod mounting seat 27. The mounting frame 15 is a rectangular frame structure. Two sliding rods 151 are provided on the mounting frame 15. The scanning gun moving pulley 14 is mounted on the sliding rods 151. Preferably, a pulley is provided in the scanner moving trolley 14 , and the pulley carries the scanner moving trolley 14 to slide left and right on the two sliding rods 151 ; A track crossbar 152 is provided on the inner surface of the mounting frame 15, and both ends of the track crossbar 152 are respectively fixed to the connecting rods at both ends of the mounting frame 15; A travel track 20 is provided at the right end of the track crossbar 152 , and a groove is provided in the middle of the travel track 20 ; The wave bar mounting base 27 is a square frame structure, including a toggle bar rotating shaft 5 and a toggle bar 23. The toggle bar rotating shaft 5 is mounted on the upper crossbar of the wave bar mounting base 27, and the toggle bar 23 extends downward through the toggle bar rotating shaft 5. Preferably: a toggle rod connector 3 is provided at the upper end of the toggle rod 23, and an anchor ring of the scanner shift cable 7 is provided at the lowest end of the lower end of the toggle rod 23; Preferably, the mounting frame 15 and the toggle lever mounting base 27 are both fixedly mounted on the workstation floor, with the toggle lever mounting base 27 being in the front, facing the position where the indicator ticket 2 is pasted on the vehicle body boom 1; Preferably, the mounting frame 15 is staggered with the toggle rod mounting seat 27 , wherein the mounting frame 15 is provided with the third pulley 6 and one end of the second pulley 21 aligned with the toggle rod 23 mounted on the toggle rod mounting seat 27 .
[0007] Beneficial technical effects: 1. Make an automatic scanning mechanism. With the force of the production line moving the boom forward, it drives the connecting rod mechanism, transmits power through the pull rope, drives the scanning mechanism to the specified position, and then touches the travel switch through the mechanism, causing the push-type finger switch to move forward, pressing and completing the action of automatically pressing the scanner switch; 2. The push-type finger switch is made of discarded rubber material, so it is extensible and can avoid damage to the scanner due to travel error; 3. By adjusting the range of motion of the mechanism through the combination of pulleys, the size of the force can be converted, and the large thrust and large stroke of the boom movement can be converted into the action of pressing the push-type finger switch.
[0008] 4. The structure of the present invention replaces the manual operation of the scanner gun. When a vehicle enters the scanning area, the invention mechanism automatically moves to the QR code scanning position. Then, the limit switch drives the push-type finger switch mechanism to move, and automatically presses the scanner gun switch to complete the ticket scanning operation; 5. The mechanism has low material cost, is automated, requires no manual operation, is safe and practical, operates smoothly, and has a low failure rate. It can be used in a wide range of production lines. BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Figure 1 A schematic diagram of the structure of the present invention in a preparation state; Figure 2 This is a schematic diagram of the structure of the present invention when scanning; Figure 3 For the present invention Figure 1 The middle circle A is an enlarged side structural diagram; Figure 4 For the present invention Figure 1 Side view of circle A in the middle.
[0010] In the picture: Car body boom-1, instruction ticket-2, toggle lever connector-3, QR code-4, toggle lever rotation axis-5, third cable pulley-6, pulley-61, scanner shift cable-7, scanner slide sleeve-8, scanner cable steering pulley-9, scanner cable-91, scanner cable anchor-10, scanner-11, scanner travel switch rod-12, scanner mounting frame-13, scanner moving pulley-14, mounting frame-15, sliding rod-151, track crossbar-152, Scanner gun mounting platform-16, scanner gun travel wheel-17, scanner gun switch cable anchor-18, scanner gun cable pulley-19, scanner gun cable-91, travel track-20, second cable pulley 21, first cable pulley-22, toggle lever-23, scanner gun press finger-24, scanner gun mounting base-25, counterweight block-26, toggle lever mounting base-27, scanner gun sliding track-28, spring hanging arm-29, spring fulcrum-30, spring-31, push-type finger switch-32.
[0011] Example In order to further illustrate the structure and implementation of the present invention, embodiments of the present invention are given below in conjunction with the accompanying drawings. It should be noted that the drawings provided by the present invention are line-type structural diagrams, and the actual object is a structure composed of metal rods, which is understandable to ordinary technicians in this field.
[0012] Example 1: Structure and connection relationship, function and effect of the present invention See attached Figure 1-4 The specific driving principle is as follows: the present invention produces an automatic scanning mechanism, which mainly uses the force of the vehicle body boom 1 moving forward on the production line to push the toggle rod connector 3, driving the connecting rod mechanism to move. The movement of the connecting rod mechanism is mainly driven by the power transmitted by the pull rope, driving the scanning mechanism to the specified position, and then the scanning gun pressing finger 24 is used to move the scanning gun pressing finger 24 forward, pressing and completing the action of automatically pressing the scanning gun switch; The structure of the present invention includes: a scanning structure, a wire drawing structure and a scanning mounting platform structure. The scanning structure is composed of a scanning gun sliding sleeve 8, a scanning gun cable pulley 9, a scanning gun cable anchor point 10, a scanning gun 11, a scanning gun travel switch rod 12, a scanning gun mounting frame 13, a scanning gun moving pulley 14, a mounting frame 15, a scanning gun mounting platform 16, and a scanning gun travel wheel 17; the scanning gun 11 is installed on a scanning gun mounting base 25, a scanning gun sliding track 28 is provided between the scanning gun 11 and the scanning gun mounting base 25, and a scanning gun sliding sleeve 8 is provided on the scanning gun sliding track 28; a spring 31 is provided at the tail end of the scanning gun sliding sleeve 8, and the spring 31 is hung on the spring hanging arm 29 after passing through the spring fulcrum 30. The spring fulcrum 30 forms a spring 31 to exert a pulling force on the scanner slide sleeve 8 to move backward. A scanner press finger 24 is provided at the front end of the scanner slide sleeve 8. A push switch 32 for the scanner 11 is provided between the scanner 11 and the scanner slide rail 28. The scanner press finger 24 is arranged to face the push switch 32 of the scanner 11. The push switch 32 of the scanner 11 is in a fixed position and does not move. The scanner press finger 24 moves with the scanner slide sleeve 8. A scanner cable steering pulley 9 is provided on the scanner mounting base 25. The scanner cable 19 passes over the scanner cable steering pulley 9 and is anchored at the front end of the scanner slide sleeve 8. Preferably, the scanning structure is mounted on a scanner mounting frame 13, and the scanner mounting frame 13 is mounted on a scanner mounting platform 16. One end of the scanner mounting platform 16 is connected to a scanner mounting platform cable 71, and the other end is fixedly connected to a scanner shift cable 7. The above structure replaces the manual operation of the scanner. When a vehicle enters the scanning area, the mechanism automatically moves to the QR code scanning position, and then drives the push-type finger switch mechanism to move through the travel switch, and automatically presses the scanner switch to complete the scanning operation of the indicated ticket. The cable structure includes a scanner cable 91 and a scanner shift cable 71; the scanner cable 91 passes through the pulley 19, the tail end of which is fixed to the scanner switch cable anchor point 18 set in the middle of the scanner travel switch rod 12, and the upper end passes through the scanner cable diverting pulley 9 and is anchored to the front end of the scanner sliding sleeve 8; the scanner mounting platform cable 71 passes through the pulley 61, the tail end is anchored to the counterweight block 26, and the other end is connected to the rear end of the scanner mounting platform 16. The front end of the scanner mounting platform 16 is fixedly connected to the scanner shift cable 7, and the scanner shift cable 7 passes through the third cable pulley 6, the second cable pulley 21, and the first cable pulley 22 and is fixed to the lower end of the toggle rod 23; The scanning mounting platform structure includes a mounting frame 15 for the scanning gun 11 and a toggle rod mounting seat 27. The mounting frame 15 is a rectangular frame structure. Two sliding rods 151 are provided on the mounting frame 15. The scanning gun moving pulley 14 is installed on the sliding rods 151; a pulley is provided in the scanning gun moving pulley 14, and the pulley carries the scanning gun moving pulley 14 to slide left and right on the two sliding rods 151; a track crossbar 152 is provided on the inner surface of the mounting frame 15, and the two ends of the track crossbar 152 are respectively fixed to the connecting rods at both ends of the mounting frame 15; a travel track 20 is provided at the right end of the track crossbar 152, and a groove is provided in the middle of the travel track 20; the wave rod mounting seat 27 is a square frame structure. The structure includes a toggle rod rotating shaft 5 and a toggle rod 23. The toggle rod rotating shaft 5 is installed on the upper cross bar of the wave rod mounting seat 27, and the toggle rod 23 extends downward through the toggle rod rotating shaft 5; a toggle rod connector 3 is provided at the upper end of the toggle rod 23, and an anchor ring for the scanner gun shift pull wire 7 is provided at the lowest end of the lower end extension of the toggle rod 23; the mounting frame 15 and the toggle rod mounting seat 27 are both fixedly installed on the workstation floor, wherein the toggle rod mounting seat 27 is in front and is installed facing the position where the instruction ticket 2 is pasted on the vehicle body boom 1; the mounting frame 15 and the toggle rod mounting seat 27 are staggered, wherein the mounting frame 15 is provided with a third pull wire pulley 6 and one end of the second pull wire pulley 21, which are aligned in a line with the toggle rod 23 installed on the toggle rod mounting seat 27. Make an automatic scanning mechanism. With the force of the production line moving the boom forward, it drives the connecting rod mechanism, transmits power through the pull rope, drives the scanning mechanism to the specified position, and then touches the travel switch through the mechanism, causing the push-type finger switch to move forward, pressing and completing the action of automatically pressing the scanner switch; Example 2 Description of the working process of the present invention On the production line, when the vehicle body boom 1 carrying the vehicle to be installed moves toward this device, the instruction ticket 2 is attached thereto. When the vehicle body boom 1 moves to the position where the toggle rod mounting seat 27 is provided, since the height of the toggle rod 23 is higher than the lower end surface of the vehicle body boom 1, when the vehicle body boom 1 moves, it will push the toggle rod 23 to move. Under the action of the toggle rod rotating shaft 5, the lower end of the toggle rod 23 moves in the opposite direction and pulls the scanning gun shift cable 7 fixedly connected to the lower end of the toggle rod 23 to move. The scanning gun shift cable 7 passes through the first cable pulley-22 and the third cable pulley 6 and carries the scanning gun mounting platform 16 to The scanner moves right. Since a scanner shift cable is connected to one end of the scanner mounting platform 16, and the scanner shift cable is connected to the counterweight 26 at the lower end through the pulley 61, when the scanner mounting platform 16 moves to the right, the counterweight 26 also moves upward; when the scanner mounting platform 16 moves to the right, the scanner travel switch rod 12 set at the lower end of the scanner mounting platform 16 will also move together. When the scanner travel switch rod 12 moves to the position of the set travel track 20, under the pulling force of the scanner shift cable 7, the scanner travel switch rod 12 is blocked by the travel track 20 and will change from a vertical state to an inclined state and be pulled to On the travel track 20, when the scanner travel switch rod 12 becomes an inclined state, the scanner gun pull wire 91 connected to the scanner gun travel switch rod 12 will be pulled downward, and the scanner gun pull wire 91 passes through the upper end of the scanner gun pull wire turning pulley 9 and pulls the scanner gun sliding sleeve 8 connected to its front end toward the scanner, and the scanner gun 11 moves. When the scanner gun pressing finger 24 provided on the scanner gun sliding sleeve 8 moves to the push-type finger switch 32 of the scanner gun 11, it presses the push-type finger switch 32 under the tension. When the scanner gun 11 contacts the push-type finger switch 32, the position of the scanner gun 11 on the scanner gun mounting platform 16 just reaches the alignment with the indicated ticket. position, at this time, the push-type finger switch 32 is pressed by the scanner pressing finger 24, and the QR code on the indication ticket is scanned to complete the information collection of the QR code content. In this way, an automatic scanning process is completed. After completion, the vehicle body boom 1 moves past the original working position, the toggle rod-23 loses thrust, and under the action of the counterweight block 26, the scanner shift cable 7 is pulled backward, bringing the scanner 11 back to its original position. In the process of the scanner shift cable 7 being pulled backward and returning to its original position, the set scanner travel switch rod 12 leaves the travel track 20 and becomes a free downward state. This is because the spring 31 set at the tail end of the scanner sliding sleeve 8 is stretched through the turning of the spring fulcrum 30, bringing the scanner sliding sleeve 8 back to its position, completing a scanning task.
[0013] Furthermore: The length and installation position of the pull wire provided in the present invention can be determined through simple calculations or a limited number of experiments. This is common knowledge known to ordinary technicians in this technical field. Therefore, the calculation method of the pull wire length is not introduced in detail in this specification.
Claims
1. The automatic scanning device for the QR code of the automobile production line instruction ticket includes a scanning structure, a wire pulling structure and a scanning mounting platform structure: The scanning structure is composed of a scanning gun sliding sleeve (8), a scanning gun cable pulley (9), a scanning gun cable anchor point (10), a scanning gun (11), a scanning gun travel switch rod (12), a scanning gun mounting frame (13), a scanning gun moving pulley (14), a mounting frame (15), a scanning gun mounting platform (16), and a scanning gun travel wheel (17); The scanning gun (11) is mounted on a scanning gun mounting base (25), a scanning gun sliding track (28) is provided between the scanning gun (11) and the scanning gun mounting base (25), and a scanning gun sliding sleeve (8) is provided on the scanning gun sliding track (28); A spring (31) is provided at the tail end of the scanning gun sliding sleeve (8); A scanning gun pressing finger (24) is provided at the front end of the scanning gun sliding sleeve (8), and a pressing switch (32) of the scanning gun (11) is provided between the scanning gun (11) and the scanning gun sliding track (28); The pulling wire structure includes a scanning gun pulling wire (91) and a scanning gun shifting pulling wire (71); The scanner wire (91) passes through the pulley (19), and the tail end is fixed to the scanner switch wire anchor point (18) set in the middle of the scanner travel switch rod (12), and the upper end passes through the scanner wire steering pulley (9) and is anchored to the front end of the scanner sliding sleeve 8; The scanning gun mounting platform pull wire (71) passes through the pulley (61), the tail end is anchored to the counterweight (26), and the other end is connected to the rear end of the scanning gun mounting platform (16). The front end of the scanning gun mounting platform (16) is fixedly connected to the scanning gun shift pull wire (7), and the scanning gun shift pull wire (7) passes through the third pull wire pulley (6), the second pull wire pulley (21), and the first pull wire pulley (22) and is fixed to the lower end of the toggle rod (23); The scanning mounting platform structure includes a mounting frame (15) for a scanning gun (11) and a toggle rod mounting seat (27), wherein the mounting frame (15) is a rectangular frame structure, and two sliding rods (151) are provided on the mounting frame (15), and a scanning gun moving pulley (14) is mounted on the sliding rods (151); The wave rod mounting seat (27) is a square frame structure, comprising a toggle rod rotating shaft (5) and a toggle rod (23). The toggle rod rotating shaft (5) is mounted on the upper crossbar of the wave rod mounting seat (27), and the toggle rod (23) extends downward through the toggle rod rotating shaft (5).
2. The automatic scanning device for the QR code of the automobile production line instruction ticket according to claim 1 is characterized in that: The spring (31) is hung on the spring hanging arm (29) after passing through the spring fulcrum (30), and the spring (31) passes through the spring fulcrum (30) to form a pulling force for the scanning gun sliding sleeve (8) to move backward.
3. The automatic scanning device for the QR code of the automobile production line instruction ticket according to claim 1 is characterized in that: The scanning gun pressing finger (24) and the pressing switch (32) of the scanning gun (11) are in a facing position.
4. The automatic scanning device for the QR code of the automobile production line instruction ticket according to claim 1 is characterized in that: The push switch (32) of the scanning gun (11) is in a fixed position and does not move, and the scanning gun pressing finger (24) moves with the scanning gun sliding sleeve (8).
5. The automatic scanning device for the QR code of the automobile production line instruction ticket according to claim 1 is characterized in that: The scanning structure is mounted on a scanning gun mounting frame (13), and the scanning gun mounting frame (13) is mounted on a scanning gun mounting platform (16). One end of the scanning gun mounting platform (16) is connected to a scanning gun mounting platform pull wire (71), and the other end is fixedly connected to a scanning gun shift pull wire (7).
6. The automatic scanning device for the QR code of the automobile production line instruction ticket according to claim 1 is characterized in that: A scanning gun cable steering pulley (9) is provided on the scanning gun mounting base (25), and the scanning gun cable (91) passes around the scanning gun cable steering pulley (9) and is anchored at the front end of the scanning gun sliding sleeve (8).
7. The automatic scanning device for the QR code of the automobile production line instruction ticket according to claim 1 is characterized in that: A pulley is provided in the scanning gun moving trolley (14), and the pulley carries the scanning gun moving trolley (14) to slide left and right on two sliding rods (151).
8. The automatic scanning device for the QR code of the automobile production line instruction ticket according to claim 1 is characterized in that: A track crossbar (152) is provided on the inner surface of the installation frame (15), and both ends of the track crossbar (152) are respectively fixed to the connecting rods at both ends of the installation frame (15); A travel track (20) is provided at the right end of the track crossbar (152), and a groove is provided in the middle of the travel track (20).
9. The automatic scanning device for the QR code of the automobile production line instruction ticket according to claim 1 is characterized in that: A toggle rod connector (3) is provided at the upper end of the toggle rod (23), and an anchor ring for a scanning gun shift wire (7) is provided at the lowest end extending from the lower end of the toggle rod (23).
10. The automatic scanning device for the QR code of the automobile production line instruction ticket according to claim 1 is characterized in that: The mounting frame (15) and the toggle rod mounting seat (27) are both fixedly mounted on the workstation floor, wherein the toggle rod mounting seat (27) is in front and is mounted facing the position where the instruction ticket (2) is pasted on the vehicle body boom (1). The mounting frame (15) and the toggle rod mounting seat (27) are staggered, wherein the mounting frame (15) is provided with a third pull wire pulley (6) and one end of the second pull wire pulley (21) and the toggle rod (23) mounted on the toggle rod mounting seat (27) are aligned in a line.