Electronic component waste recycling and crushing device

Abstract

The utility model discloses an electronic component waste recycling and crushing device, and particularly relates to the technical field of crushing devices.The electronic component waste recycling and crushing device comprises a base, a first working box, a second working box, a feeding adjustable assembly and a crushing gas treatment device, the first working box is arranged on the upper end face of the base, and the second working box is arranged in an inner cavity of the first working box; a feeding adjustable assembly is arranged in an inner cavity of the second working box, a smashing gas treatment device is arranged on one side of the feeding adjustable assembly, and a smashing mechanism is arranged on one side of the feeding adjustable assembly. Electronic component waste is fed through the feeding port, the feeding speed is adjusted through the feeding adjustable assembly, the electronic component waste is smashed through the smashing mechanism, and dust fall and gas purification are conducted on powder generated in the smashing process through the smashing gas treatment device in the smashing process; and the situation that secondary pollution is easily caused due to the fact that dust or volatile organic compounds containing heavy metal are possibly generated in the crushing process is avoided.

Description

Technical Field

[0001] This utility model relates to the field of crushing device technology, and more specifically, to a crushing device for recycling electronic component waste. Background Technology

[0002] Electronic component waste recycling and crushing equipment is a type of mechanical equipment specifically designed for processing waste electronic components. Its main function is to break down waste electronic components into smaller particles or fragments through physical crushing, facilitating subsequent separation, sorting, and resource utilization. This equipment plays a crucial role in electronic waste recycling and processing, effectively improving resource recovery rates and reducing environmental pollution.

[0003] For example, application number CN202121430798.5 discloses a waste electronic component recycling crushing and separation device, which solves the problem that "the waste electronic component recycling devices used in the market usually compress waste electronic components into blocks for recycling. Some waste electronic components are still relatively large in size after being compressed into blocks, which is not convenient for recycling. They cannot be crushed into smaller waste materials for centralized processing. Moreover, waste electronic components will generate waste materials of different sizes after crushing, which cannot be separated and centrally processed." However, when crushing waste electronic components, dust containing heavy metals or volatile organic compounds may be generated during the crushing process, which can easily cause secondary pollution.

[0004] Therefore, a waste recycling and crushing device for electronic components is proposed to address the above problems. Utility Model Content

[0005] In order to overcome the above-mentioned defects of the prior art, the present invention provides an electronic component waste recycling and crushing device to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, this utility model provides the following technical solution: an electronic component waste recycling and crushing device, comprising a base, a first working box, a second working box, an adjustable feeding component, and a crushing gas treatment device. The first working box is provided on the upper surface of the base, and the second working box is provided in the inner cavity of the first working box. The adjustable feeding component is provided in the inner cavity of the second working box, and the crushing gas treatment device is provided on one side of the adjustable feeding component. The upper surface of the second working box passes through the first working box and is connected to a feed inlet.

[0007] The pulverized gas treatment device includes a dust suppression mechanism and a gas treatment mechanism. The dust suppression mechanism is installed in the inner cavity of the second working chamber, and the gas treatment mechanism is provided on the side wall of the inner cavity of the second working chamber. The dust suppression mechanism includes a water tank and a water inlet. The water tank is installed in the inner cavity of the second working chamber and is connected to the water inlet. The lower part of the water tank is connected to the input end of a water pump through a water pipe, and the output end of the water pump is connected to a fixed frame through a water pipe. A spray nozzle is provided on the lower end face of the fixed frame.

[0008] Preferably, the gas processing mechanism includes an air inlet and an exhaust outlet, both of which are installed on the side end face of the second working box, with the air inlet specifically installed below the exhaust outlet. An exhaust fan is provided on the inner side of both the air inlet and the exhaust outlet, and a filter screen is provided on both sides of the exhaust fan. A first guide block is provided on one side of the air inlet, and a vent hole is provided transversely through the side end face of the first guide block. A grid plate is provided at the edge of the first guide block, and a filter screen is provided on the upper and lower end faces of the grid plate.

[0009] Preferably, the adjustable feeding component includes a second guide block and a hydraulic telescopic rod. The second guide block is installed in the inner cavity of the second working box, and a hydraulic telescopic rod is provided on the upper end face of the second guide block. A third guide block is provided at the telescopic end of the hydraulic telescopic rod, and a fourth guide block is provided above the third guide block. A groove is provided on the side wall of the inner cavity of the second working box, and a telescopic plate is provided on the bottom end face of the third guide block.

[0010] Preferably, a crushing mechanism is provided on one side of the adjustable feeding component, and a discharge port is provided below the crushing mechanism. A slider is provided on the side wall of the third guide block, and the third guide block is slidably connected to a groove through the slider on the side end face.

[0011] Preferably, the crushing mechanism includes a driving mechanism, a first crushing roller, and a second crushing roller. The driving mechanism is installed between the first working box and the second working box, and the output end of the driving mechanism is respectively connected to the first crushing roller and the second crushing roller. The driving mechanism includes a stepper motor and a first gear. The output end of the stepper motor is provided with the first gear, and the first gear is connected to a first double gear shaft through a first chain. The first double gear shaft is connected to a second double gear shaft through a second chain, and the second double gear shaft is connected to a second gear through a third chain.

[0012] Preferably, the water tank and the water inlet form a connected structure, the water tank and the spray nozzle are connected to the water pump through a water pipe, and the air inlet forms a connected structure with the exhaust port through the vent hole dug in the inner cavity of the second working box and the side end face of the first guide block.

[0013] Preferably, the feed inlet is connected to the discharge outlet through the first working box and the second working box, the third guide block is connected to the second working box through the slider and the groove, and the third guide block is connected to the second working box through the groove.

[0014] Preferably, the drive mechanism is provided with four sets, with two sets each for the first and second crushing rollers. The first double gear shaft, the second double gear shaft, and the second gear are installed at both ends of the two sets of first crushing rollers and the two sets of second crushing rollers. The outer surfaces of the first and second crushing rollers are respectively equipped with conical teeth and triangular conical teeth. The stepper motor forms a chain drive structure with the first and second crushing rollers through the first gear, the first chain, the first double gear shaft, the second chain, the second double gear shaft, the third chain, and the second gear.

[0015] The technical effects and advantages of this utility model are as follows:

[0016] Compared with existing technologies, this electronic component waste recycling and crushing device is used in which electronic component waste is fed into the feed inlet, the feeding speed is adjusted by the feed adjustable component, and then the electronic component waste is crushed by the crushing mechanism. During the crushing process, the powder generated during the crushing process is dusted and the gas is purified by the crushing gas treatment device, thereby avoiding the situation that "dust containing heavy metals or volatile organic compounds may be generated during the crushing process, which may easily cause secondary pollution".

[0017] Compared with existing technologies, this electronic component waste recycling and crushing device uses a crushing gas treatment device to reduce dust and purify the powder gas generated during the crushing process. A washing liquid is injected into the water tank through the inlet, and a water pump is started. The pump discharges the washing liquid from the spray nozzle through a water pipe. The washing liquid fully contacts the dust-laden gas, washing away the dust particles and purifying the gas. Simultaneously, the gas is discharged through the gas treatment mechanism. An exhaust fan is started, with the exhaust fan inside the inlet and outlet facing opposite directions. This allows the gas to pass through the ventilation holes dug into the side end face of the inlet and the first guide block, and the gas is discharged through the grid plate from the inlet. This facilitates dust reduction and gas purification by assisting the dust reduction mechanism, and also facilitates directional gas discharge, avoiding the situation where "dust containing heavy metals or volatile organic compounds may be generated during the crushing process, which could easily cause secondary pollution."

[0018] Compared with existing technologies, this electronic component waste recycling and crushing device utilizes an adjustable feeding component to regulate the feeding speed at the inlet. It activates a hydraulic telescopic rod, which drives a third guide block to slide up and down along a slider, groove, and recess. The shortest distance between the third and fourth guide blocks gradually decreases from top to bottom. By adjusting this shortest distance, the feeding speed at the inlet is regulated. Simultaneously, as the third guide block moves up and down, the telescopic plate extends and retracts, preventing the electronic component waste from affecting the vertical extension and retraction of the hydraulic telescopic rod. This structure allows for adjustment of the feeding speed, facilitating the crushing of electronic component waste.

[0019] Compared with existing technologies, this electronic component waste recycling and crushing device is in use. The electronic component waste is fed into the feed inlet, and the feeding speed is adjusted by the feed adjustable component. Then, the electronic component waste is crushed by the crushing mechanism. The stepper motor in the drive mechanism is started. Since the stepper motor forms a chain drive structure with the first crushing roller and the second crushing roller through the first gear, the first chain, the first double gear shaft, the second chain, the second double gear shaft, the third chain and the second gear, it is convenient to drive the first crushing roller and the second crushing roller to crush the electronic component waste. This makes it easier to obtain electronic component waste with small shape. Finally, the crushed electronic component waste is discharged from the discharge port. Attached Figure Description

[0020] Figure 1 This is a three-dimensional structural diagram of the first working box of this utility model.

[0021] Figure 2 This is a schematic diagram of the cross-sectional structure of the dust suppression mechanism of this utility model.

[0022] Figure 3 This is a schematic diagram of the front section structure of the gas processing mechanism of this utility model.

[0023] Figure 4 This is a top-section structural diagram of the adjustable feeding component of this utility model.

[0024] Figure 5 This is a frontal cross-sectional view of the crushing mechanism of this utility model.

[0025] Figure 6 This is a schematic diagram of the three-dimensional structure of the second crushing roller of this utility model.

[0026] The attached figures are labeled as follows: 1. Base; 2. First working box; 3. Second working box; 4. Adjustable feeding component; 41. Second guide block; 42. Hydraulic telescopic rod; 43. Third guide block; 44. Fourth guide block; 45. Groove; 46. Telescopic plate; 5. Crushing gas treatment device; 51. Dust suppression mechanism; 511. Water tank; 512. Water inlet; 513. Water pump; 514. Fixing frame; 515. Spray nozzle; 52. Gas treatment mechanism; 521. Air inlet; 522. Exhaust outlet. 523. Exhaust fan; 524. First guide block; 525. Vent hole; 526. Grating plate; 6. Feed inlet; 7. Crushing mechanism; 71. Drive mechanism; 711. Stepper motor; 712. First gear; 713. First chain; 714. First double gear shaft; 715. Second chain; 716. Second double gear shaft; 717. Third chain; 718. Second gear; 72. First crushing roller; 73. Second crushing roller; 8. Discharge port; 9. Slider; 10. Slide groove. Detailed Implementation

[0027] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0028] Example

[0029] As attached Figures 1 to 6 The illustrated electronic component waste recycling and crushing device includes a base 1, a first working box 2, a second working box 3, a feeding adjustable component 4, and a crushing gas treatment device 5. The first working box 2 is located on the upper surface of the base 1, and the second working box 3 is located within the inner cavity of the first working box 2. The feeding adjustable component 4 is located within the inner cavity of the second working box 3, allowing for adjustment of the feeding speed. The crushing gas treatment device 5 is located on one side of the feeding adjustable component 4. During the crushing process, the crushing gas treatment device 5 reduces dust and purifies the gas generated during crushing, preventing dust accumulation that may occur during the crushing process. Dust containing heavy metals or volatile organic compounds can easily cause secondary pollution. The upper end of the second working box 3 is connected to the first working box 2 through the inlet 6. Electronic component waste is fed in through the inlet 6. A crushing mechanism 7 is set on one side of the feeding adjustable component 4. The crushing mechanism 7 crushes the electronic component waste. An outlet 8 is set below the crushing mechanism 7. A slider 9 is set on the side wall of the third guide block 43. The third guide block 43 is slidably connected to the slide groove 10 through the slider 9 on the side end face. The inlet 6 is connected to the outlet 8 through the first working box 2 and the second working box 3.

[0030] The device utilizes a pulverizing gas treatment unit 5 to reduce dust and purify the powder gas generated during the pulverizing process. The pulverizing gas treatment unit 5 includes a dust reduction mechanism 51 and a gas treatment mechanism 52. The dust reduction mechanism 51 is installed inside the second working chamber 3, and the gas treatment mechanism 52 is located on the side wall of the inner cavity of the second working chamber 3. The dust reduction mechanism 51 includes a water tank 511 and a water inlet 512. The water tank 511 is installed inside the second working chamber 3 and is connected to the water inlet 512. A washing liquid is poured into the inner cavity of the water tank 511 through the water inlet 512. The lower part of the water tank 511 is connected to a water pipe... The system includes an input terminal for a water pump 513, and an output terminal for the water pump 513 connected to a mounting bracket 514 via a water pipe. A spray nozzle 515 is mounted on the lower end of the mounting bracket 514. A water tank 511 and an inlet 512 form a communication structure. The water tank 511 and the spray nozzle 515 are connected to the water pump 513 via a water pipe. When the water pump 513 is started, it uses the water pipe to discharge the washing liquid from the spray nozzle 515. The washing liquid comes into full contact with the dust-laden gas, washing away dust particles and purifying the gas. The gas treatment mechanism 52 includes an air inlet 521 and an exhaust outlet 522. The air inlets 522 are all installed on the side end face of the second working box 3, and the air inlet 521 is specifically installed below the exhaust outlet 522. Exhaust fans 523 are installed inside both the air inlet 521 and the exhaust outlet 522, and filters are installed on both sides of the exhaust fans 523. A first guide block 524 is installed on one side of the air inlet 521, and a vent hole 525 is transversely provided on the side end face of the first guide block 524. A grille plate 526 is installed at the edge of the first guide block 524, and filters are installed on the upper and lower ends of the grille plate 526. When the exhaust fan 523 is started, the air inlet 521 and the exhaust outlet... The exhaust fan 523 inside 522 blows in the opposite direction. The gas is ventilated through the air inlet 521 and the ventilation hole 525 dug on the side end face of the first guide block 524. The gas is discharged from the air inlet 521 through the grid plate 526. This is conducive to the dust suppression mechanism 51 to perform dust suppression and gas purification, and facilitates the directional discharge of gas. It avoids the situation that "dust containing heavy metals or volatile organic compounds may be generated during the crushing process, which may easily cause secondary pollution". The air inlet 521 forms a communication structure with the exhaust port 522 through the inner cavity of the second working box 3 and the ventilation hole 525 dug on the side end face of the first guide block 524.

[0031] The feeding speed of the feed inlet 6 is adjusted by the adjustable feeding component 4. The adjustable feeding component 4 includes a second guide block 41 and a hydraulic telescopic rod 42. The second guide block 41 is installed in the inner cavity of the second working box 3, and the upper end face of the second guide block 41 is provided with the hydraulic telescopic rod 42. The telescopic end of the hydraulic telescopic rod 42 is provided with a third guide block 43, and a fourth guide block 44 is provided above the third guide block 43. The shortest distance between the third guide block 43 and the fourth guide block 44 gradually shortens from top to bottom. The side wall of the inner cavity of the second working box 3 is provided with a groove 45, and the bottom end face of the third guide block 43 is provided with a telescopic plate 46. When the block 43 moves up and down, the telescopic plate 46 extends and retracts up and down to prevent the waste electronic components from affecting the extension and retraction of the hydraulic telescopic rod 42. The third guide block 43 forms a sliding structure with the second working box 3 through the slider 9 and the slide groove 10. The third guide block 43 forms a sliding structure with the second working box 3 through the groove 45. The feeding speed of the feed port 6 is adjusted by adjusting the shortest distance between the third guide block 43 and the fourth guide block 44. The hydraulic telescopic rod 42 is started, and the hydraulic telescopic rod 42 drives the third guide block 43 to slide up and down along the slider 9, the slide groove 10 and the groove 45 to adjust the feeding speed and facilitate the crushing of the waste electronic components.

[0032] The device utilizes a crushing mechanism 7 to crush electronic component waste. The crushing mechanism 7 includes a drive mechanism 71, a first crushing roller 72, and a second crushing roller 73. The drive mechanism 71 is installed between the first working box 2 and the second working box 3, and its output end is connected to the first crushing roller 72 and the second crushing roller 73 respectively. The drive mechanism 71 includes a stepper motor 711 and a first gear 712. The first gear 712 is located at the output end of the stepper motor 711, and the first gear 712 is connected to a first double gear shaft 71 via a first chain 713. 4. The first double gear shaft 714 is connected to the second double gear shaft 716 via the second chain 715. The second double gear shaft 716 is connected to the second gear 718 via the third chain 717. The drive mechanism 71 has four sets. The first crushing roller 72 and the second crushing roller 73 each have two sets. The first double gear shaft 714, the second double gear shaft 716, and the second gear 718 are installed at both ends of the two sets of first crushing rollers 72 and the two sets of second crushing rollers 73. The outer surfaces of the first crushing roller 72 and the second crushing roller 73 are respectively equipped with conical teeth and triangular conical teeth. The stepper motor 711 in the drive mechanism 71 is activated. Since the stepper motor 711 forms a chain drive structure with the first crushing roller 72 and the second crushing roller 73 through the first gear 712, the first chain 713, the first double gear shaft 714, the second chain 715, the second double gear shaft 716, the third chain 717, and the second gear 718, it is convenient to drive the first crushing roller using the first gear 712, the first chain 713, the first double gear shaft 714, the second chain 715, the second double gear shaft 716, the third chain 717, and the second gear 718. 72 and the second crushing roller 73 crush the electronic component waste to obtain small-shaped electronic component waste. Finally, the crushed electronic component waste is discharged from the discharge port 8. In this embodiment, the hydraulic telescopic rod 42, water pump 513, spray nozzle 515, exhaust fan 523 and stepper motor 711 are all commercially available equipment known to those skilled in the art. They can be customized or selected according to actual needs. Here we only use them and do not make any structural or functional improvements. We will not go into details here.

[0033] The working process of this utility model is as follows: First, electronic component waste is fed into the feed inlet 6. The feeding speed of the feed inlet 6 is adjusted by the adjustable feeding component 4. The hydraulic telescopic rod 42 is activated, which drives the third guide block 43 to slide up and down along the slider 9, the slide groove 10 and the groove 45. The feeding speed of the feed inlet 6 is adjusted by adjusting the shortest distance between the third guide block 43 and the fourth guide block 44. At the same time, when the third guide block 43 moves up and down, the telescopic plate 46 extends and retracts up and down, and the electronic component waste is crushed by the crushing mechanism 7. The stepper motor 711 in the drive mechanism 71 is activated. Since the stepper motor 711 forms a chain drive structure with the first crushing roller 72 and the second crushing roller 73 through the first gear 712, the first chain 713, the first double gear shaft 714, the second chain 715, the second double gear shaft 716, the third chain 717 and the second gear 718, it facilitates the crushing of the first crushing roller 72 and the second crushing roller 73. The crushing roller 73 rotates to crush electronic component waste. The crushed electronic component waste is discharged from the discharge port 8. The crushing gas treatment device 5 is used to reduce dust and purify the powder gas generated during the crushing process. Washing liquid is injected into the inner cavity of the water tank 511 through the water inlet 512. The water pump 513 is started. The water pump 513 discharges the washing liquid from the spray nozzle 515 through the water pipe. The washing liquid fully contacts the dust-laden gas to wash off the dust particles and purify the gas. At the same time, the gas is discharged through the gas treatment mechanism 52. The exhaust fan 523 is started. The exhaust fan 523 inside the air inlet 521 and the exhaust port 522 has opposite air directions. The gas is ventilated through the air inlet 521 and the ventilation hole 525 dug on the side end face of the first guide block 524. The gas is discharged from the air inlet 521 through the grid plate 526. This is conducive to the dust reduction mechanism 51 to reduce dust and purify the gas, and at the same time, it facilitates the directional discharge of gas.

Claims

1. A waste recycling and crushing device for electronic components, comprising a base (1), a first working box (2), a second working box (3), an adjustable feeding assembly (4), and a crushing gas treatment device (5), characterized in that: The upper surface of the base (1) is provided with a first working box (2), and the inner cavity of the first working box (2) is provided with a second working box (3), and the inner cavity of the second working box (3) is provided with a feeding adjustable component (4). A crushing gas treatment device (5) is provided on one side of the feeding adjustable component (4), and the upper surface of the second working box (3) is connected to the first working box (2) through the feed inlet (6). The pulverized gas treatment device (5) includes a dust suppression mechanism (51) and a gas treatment mechanism (52). The dust suppression mechanism (51) is installed in the inner cavity of the second working box (3), and the gas treatment mechanism (52) is provided on the side wall of the inner cavity of the second working box (3). The dust suppression mechanism (51) includes a water tank (511) and a water inlet (512). The water tank (511) is installed in the inner cavity of the second working box (3), and the water tank (511) is connected to the water inlet (512). The lower part of the water tank (511) is connected to the input end of the water pump (513) through a water pipe, and the output end of the water pump (513) is connected to the fixed frame (514) through a water pipe. The lower end face of the fixed frame (514) is provided with a spray nozzle (515).

2. The electronic component waste recycling and crushing device according to claim 1, characterized in that: The gas processing mechanism (52) includes an air inlet (521) and an exhaust outlet (522). The air inlet (521) and the exhaust outlet (522) are both installed on the side end face of the second working box (3), and the air inlet (521) is specifically installed below the exhaust outlet (522). An exhaust fan (523) is provided on the inner side of the air inlet (521) and the exhaust outlet (522), and a filter screen is provided on both sides of the exhaust fan (523). A first guide block (524) is provided on one side of the air inlet (521), and a vent hole (525) is provided transversely through the side end face of the first guide block (524). A grid plate (526) is provided at the edge of the first guide block (524), and a filter screen is provided on the upper end face and the lower end face of the grid plate (526).

3. The electronic component waste recycling and crushing device according to claim 1, characterized in that: The adjustable feeding component (4) includes a second guide block (41) and a hydraulic telescopic rod (42). The second guide block (41) is installed in the inner cavity of the second working box (3), and the upper end face of the second guide block (41) is provided with the hydraulic telescopic rod (42). The telescopic end of the hydraulic telescopic rod (42) is provided with a third guide block (43). A fourth guide block (44) is provided above the third guide block (43). The side wall of the inner cavity of the second working box (3) is provided with a groove (45), and the bottom end face of the third guide block (43) is provided with a telescopic plate (46).

4. The electronic component waste recycling and crushing device according to claim 3, characterized in that: The adjustable feeding component (4) is provided with a crushing mechanism (7) on one side, and a discharge port (8) is provided below the crushing mechanism (7). The side wall of the third guide block (43) is provided with a slider (9), and the third guide block (43) is slidably connected to a groove (10) through the slider (9) on the side end face.

5. The electronic component waste recycling and crushing device according to claim 4, characterized in that: The crushing mechanism (7) includes a drive mechanism (71), a first crushing roller (72) and a second crushing roller (73). The drive mechanism (71) is installed between the first working box (2) and the second working box (3), and the output end of the drive mechanism (71) is connected to the first crushing roller (72) and the second crushing roller (73) respectively. The drive mechanism (71) includes a stepper motor (711) and a first gear (712). The output end of the stepper motor (711) is provided with the first gear (712), and the first gear (712) is connected to a first double gear shaft (714) through a first chain (713). The first double gear shaft (714) is connected to a second double gear shaft (716) through a second chain (715). The second double gear shaft (716) is connected to a second gear (718) through a third chain (717).

6. The electronic component waste recycling and crushing device according to claim 2, characterized in that: The water tank (511) and the water inlet (512) form a connected structure. The water tank (511) and the spray nozzle (515) are connected to the water pump (513) through a water pipe. The air inlet (521) is connected to the exhaust port (522) through the vent hole (525) dug in the inner cavity of the second working box (3) and the side end face of the first guide block (524).

7. The electronic component waste recycling and crushing device according to claim 4, characterized in that: The feed inlet (6) is connected to the discharge outlet (8) through the first working box (2) and the second working box (3). The third guide block (43) is connected to the second working box (3) through the slider (9) and the slide groove (10). The third guide block (43) is connected to the second working box (3) through the groove (45).

8. The electronic component waste recycling and crushing device according to claim 5, characterized in that: The drive mechanism (71) is provided with four sets. The first crushing roller (72) and the second crushing roller (73) are each provided with two sets. The first double gear shaft (714), the second double gear shaft (716), and the second gear (718) are installed at both ends of the two sets of first crushing rollers (72) and two sets of second crushing rollers (73). The outer surfaces of the first crushing roller (72) and the second crushing roller (73) are respectively equipped with conical teeth and triangular conical teeth. The stepper motor (711) forms a chain drive structure with the first crushing roller (72) and the second crushing roller (73) through the first gear (712), the first chain (713), the first double gear shaft (714), the second chain (715), the second double gear shaft (716), the third chain (717), and the second gear (718).

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