Supporting and leveling mechanism for self-moving tail

Abstract

The utility model relates to the technical field of mining equipment, in particular to a self-moving tail supporting and leveling mechanism which comprises a mounting seat, a telescopic adjusting assembly and a track wheel set, the mounting seat is fixedly connected with a self-moving tail, the mounting seat is provided with a containing cavity, and the lower end of the mounting seat is provided with an opening; one end of the telescopic adjusting assembly is rotationally connected with the mounting base through a horizontal connecting sleeve, and the other end of the telescopic adjusting assembly is rotationally connected with the rail wheel set through a knuckle bearing. The upper end of the rail wheel set is arranged in the containing cavity in a sliding mode in the vertical direction. When the self-moving machine tail is lifted, the telescopic adjusting assembly retracts into the containing cavity. When the self-moving machine tail is put down to the designated height, the telescopic adjusting assembly extends and controls the rail wheel set to abut against the guide rail. Through the structural design, the horizontal state of the machine tail can be maintained when the sliding rail inclines, manpower and material resources are saved, and the working efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of mining equipment, in particular to a self-moving tail support and leveling mechanism. Background Art

[0002] The walking self-moving tail is an auxiliary equipment commonly used in mining excavation working faces. It can move forward with the advancement of the tunnel boring machine while the excavation working face is working normally. When the self-moving tail is working, it is necessary to lift the slide rail off the ground, and then control the slide rail to move forward a unit stroke. Further, the friction between the slide rail and the ground is used to make the self-moving tail move forward a unit stroke along the slide rail. Continuous circulation can make the tail frame move in steps. For the uneven terrain environment of the tunnel ground, the traditional self-moving tail will tilt when placed, which is difficult to install and requires manual leveling of the ground, which is time-consuming and labor-intensive, and seriously reduces work efficiency. Utility Model Content

[0003] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, the utility model proposes a self-moving tail support leveling mechanism, which can maintain the tail in a horizontal state when the slide rail is tilted, saving manpower and material resources and improving work efficiency.

[0004] A self-moving tail support and leveling mechanism according to an embodiment of the utility model includes:

[0005] A mounting seat, wherein the mounting seat is provided with a receiving cavity, and the lower end of the mounting seat is open;

[0006] A telescopic adjustment component, wherein the telescopic adjustment component is provided with a horizontal connecting sleeve, and connecting shafts are respectively provided on both sides of the horizontal connecting sleeve, the upper end of the telescopic adjustment component is rotatably connected to the mounting seat through the connecting shaft, and the lower end of the telescopic adjustment component is provided with a joint bearing;

[0007] A track wheel set, the upper end of which is slidably arranged in the accommodating cavity along a vertical direction; the track wheel set is rotatably connected to the lower end of the telescopic adjustment component.

[0008] According to some embodiments of the utility model, the telescopic adjustment assembly includes a hydraulic cylinder, a hydraulic shaft and a piston; the hydraulic cylinder includes an inner cylinder body and an outer cylinder body, the inner cylinder body divides the outer cylinder body into a first hydraulic chamber and a second hydraulic chamber, and the piston is slidably arranged in the second hydraulic chamber; one end of the hydraulic shaft is fixedly connected to the piston, and the other end of the hydraulic shaft is fixedly connected to the joint bearing.

[0009] According to some embodiments of the utility model, the telescopic adjustment assembly also includes a first pipeline, a second pipeline and a suction sleeve; one end of the first pipeline is connected to the first hydraulic chamber, and the other end is connected to the second pipeline, and a first one-way stop valve is arranged on the first pipeline; the second pipeline is connected to the second hydraulic chamber, and the other end is connected to the suction sleeve, and a second one-way stop valve is arranged on the second pipeline; a plunger is arranged in the suction sleeve.

[0010] According to some embodiments of the present invention, the telescopic adjustment assembly further includes a third pipeline, one end of the third pipeline is connected to the first hydraulic chamber, and the other end is connected to the second hydraulic chamber, and a third one-way stop valve is arranged on the third pipeline.

[0011] According to some embodiments of the utility model, a quick reflux pipe and a trigger rod are provided on the outer cylinder, the trigger rod is passed through the quick reflux pipe and is threadedly connected to the quick reflux pipe, and one end of the trigger rod can abut the third one-way stop valve and control its opening.

[0012] According to some embodiments of the present invention, the first pipeline is connected to the first hydraulic chamber at a side close to the spherical bearing.

[0013] According to some embodiments of the present invention, the second pipeline is connected to the second hydraulic chamber at the end of the stroke of the piston.

[0014] According to some embodiments of the utility model, clamping plates are respectively provided on both sides of the mounting seat, and the connecting shaft is rotatably connected to the mounting seat through the clamping plates.

[0015] According to some embodiments of the present invention, ribs are respectively provided on both sides of the mounting seat, mounting holes are provided on the ribs, and fastening bolts are provided on the mounting holes.

[0016] According to some embodiments of the utility model, a positioning pin is also provided on the mounting seat.

[0017] A self-moving tail support leveling mechanism according to an embodiment of the utility model has at least the following beneficial effects:

[0018] According to the solution of the utility model, the support and leveling mechanism of the self-moving tail includes a mounting seat, a telescopic adjustment component and a track wheel group, wherein the mounting seat is fixedly connected to the self-moving tail, the mounting seat is provided with a accommodating cavity and the lower end is open; one end of the telescopic adjustment component is rotatably connected to the mounting seat through a horizontal connecting sleeve, and the other end of the telescopic adjustment component is rotatably connected to the track wheel group through a joint bearing. The upper end of the track wheel group is slidably arranged in the accommodating cavity along the vertical direction; when the self-moving tail is lifted, the telescopic adjustment component is retracted into the accommodating cavity; when the self-moving tail is lowered to a specified height, the telescopic adjustment component is extended and controls the track wheel group to abut against the guide rail. Through the design of this structure, when the track wheel group abuts against the guide rail, the telescopic adjustment component can provide a movable margin, which plays a role in protecting the telescopic adjustment component and increasing the service life of the telescopic adjustment component. Moreover, it can maintain the horizontal state of the tail when the slide rail is tilted, saving manpower and material resources and improving work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A structural schematic diagram of the utility model;

[0020] Figure 2 It is a schematic diagram of a cross-sectional structure of the utility model.

[0021] Figure 3 It is a cross-sectional structural schematic diagram of the telescopic adjustment component of the utility model;

[0022] Figure 4 For the utility model Figure 3 Schematic diagram of the enlarged local structure at A.

[0023] In the figure:

[0024] 100-mounting seat, 101-accommodating cavity, 110-cage, 120-rib plate, 121-mounting hole, 130-fastening bolt, 140-locating pin;

[0025] 200- telescopic adjustment assembly, 201- first pipeline, 202- second pipeline, 203- suction sleeve, 204- first one-way check valve, 205- second one-way check valve, 206- plunger, 207- third pipeline, 208- third one-way check valve, 210- horizontal connecting sleeve, 211- connecting shaft, 220- joint bearing, 230- hydraulic cylinder, 231- inner cylinder, 232- outer cylinder, 233- first hydraulic chamber, 234- second hydraulic chamber, 240- hydraulic shaft, 250- piston, 260- fast reflux pipeline, 261- trigger rod;

[0026] 300-track wheel set;

[0027] 400-Guide rails. DETAILED DESCRIPTION

[0028] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0029] In the description of the present invention, it should be understood that the descriptions involving orientation, such as the orientation or positional relationship indicated as up, down, etc., are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0030] In the description of the present utility model, "a plurality" means more than two. If there is a description of "first" or "second", it is only for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0031] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0032] Reference Figures 1 to 4 As shown, the utility model discloses a self-moving tail support leveling mechanism, including a mounting seat 100, a telescopic adjustment assembly 200 and a track wheel assembly 300. The mounting seat 100 is provided with a receiving cavity 101, and the lower end of the mounting seat 100 is provided with an opening; the telescopic adjustment assembly 200 is provided with a horizontal connecting sleeve 210, and connecting shafts 211 are respectively provided on both sides of the horizontal connecting sleeve 210. The upper end of the telescopic adjustment assembly 200 is rotatably connected to the mounting seat 100 through the connecting shaft 211, and the lower end of the telescopic adjustment assembly 200 is provided with a joint bearing 220; the upper end of the track wheel assembly 300 is slidably arranged in the receiving cavity 101 along the vertical direction; the track wheel assembly 300 and the lower end of the telescopic adjustment assembly 200 are rotatably connected.

[0033] Specifically, in the present embodiment, the self-moving tail support and leveling mechanism includes a mounting seat 100, a telescopic adjustment assembly 200 and a track wheel assembly 300, wherein the mounting seat 100 is fixedly connected to the self-moving tail, the mounting seat 100 is provided with a accommodating cavity 101 and an opening is provided at the lower end; one end of the telescopic adjustment assembly 200 is rotatably connected to the mounting seat 100 through a horizontal connecting sleeve 210, and the other end of the telescopic adjustment assembly 200 is rotatably connected to the track wheel assembly 300 through a joint bearing 220. The upper end of the track wheel set 300 is slidably arranged in the accommodating cavity 101 along the vertical direction; in this embodiment, the upper end of the track wheel set 300 and the accommodating cavity 101 are clearance-matched, and the upper end of the track wheel set 300 has an adjustable margin when entering the accommodating cavity 101 through the design of this structure; when the self-moving tail is lifted, the telescopic adjustment component 200 shrinks and enters the accommodating cavity 101; when the self-moving tail is lowered to a specified height, the telescopic adjustment component 200 extends and controls the track wheel set 300 to abut against the guide rail 400. When abutting against the guide rail 400, if the guide rail 400 is tilted due to uneven ground, the telescopic adjustment component 200 can control the distance between the mounting seat 100 and the track wheel set 300, so that the track wheel set 300 can abut against the guide rail 400 stably while maintaining the balance of the self-moving tail. Since the track wheel set 300 usually has a plurality of track wheels distributed along the length direction of the track, the contact mode between the track wheel set 300 and the guide rail 400 is surface contact. When the guide rail 400 is tilted, if the track wheel set 300 still abuts the guide rail 400 in a horizontal manner, the track wheel set 300 will be unevenly stressed, thereby causing the reaction force on the telescopic adjustment assembly 200 to be too large and causing damage to it. In this embodiment, the upper end of the telescopic adjustment assembly 200 is rotatably connected to the mounting seat 100 through the connecting shaft 211, and the axis of the connecting shaft 211 is horizontally arranged. Through the design of this structure, the telescopic adjustment assembly 200 can rotate in a small range around the horizontal axis, and the range of rotation is that one side of the track wheel set 300 abuts against the mounting seat 100. Through the design of this structure, the inclination direction of the track wheel set 300 and the guide rail 400 can be adjusted to be consistent. Moreover, in the present embodiment, by providing a joint bearing 220 at the lower end of the telescopic adjustment assembly 200, the joint bearing 220 can control the track wheel assembly 300 to make a small range of adjustment in the space area to match the placement form of different guide rails 400. It can be understood that, in the present embodiment, the telescopic adjustment assembly 200 can be a linear drive mechanism that can be extended or shortened, such as a hydraulic cylinder, a pneumatic cylinder or an electric cylinder. Through the design of this structure, when the track wheel assembly 300 abuts against the guide rail 400, the telescopic adjustment assembly 200 can provide a margin of movement, which plays a role in protecting the telescopic adjustment assembly 200 and improving the service life of the telescopic adjustment assembly 200. Moreover, when the slide rail is tilted, the tail can be maintained in a horizontal state, which saves manpower and material resources and improves work efficiency.

[0034] In some embodiments of the utility model, the telescopic adjustment assembly 200 includes a hydraulic cylinder 230, a hydraulic shaft 240 and a piston 250; the hydraulic cylinder 230 includes an inner cylinder body 231 and an outer cylinder body 232, the inner cylinder body 231 divides the outer cylinder body 232 into a first hydraulic chamber 233 and a second hydraulic chamber 234, and the piston 250 is slidably arranged in the second hydraulic chamber 234; one end of the hydraulic shaft 240 is fixedly connected to the piston 250, and the other end of the hydraulic shaft 240 is fixedly connected to the joint bearing 220.

[0035] Specifically, in this embodiment, the telescopic adjustment assembly 200 includes a hydraulic cylinder 230, a hydraulic shaft 240 and a piston 250. The hydraulic cylinder 230 includes an inner cylinder 231 and an outer cylinder 232; the inner cylinder 231 divides the outer cylinder 232 into a first hydraulic chamber 233 and a second hydraulic chamber 234. Specifically, the inner cylinder 231 and the outer cylinder 232 are coaxially arranged, and the outer wall diameter of the inner cylinder 231 is smaller than the inner wall diameter of the outer cylinder 232. The first hydraulic chamber 233 and the second hydraulic chamber 234 are filled with hydraulic oil. The piston 250 is arranged in the second hydraulic chamber 234, that is, in the inner cylinder 231. In the process of injecting hydraulic oil from the first hydraulic chamber 233 into the second hydraulic chamber 234, the piston 250 can be pushed to move outward in the inner cylinder 231, thereby driving the hydraulic shaft 240 to move outward along a straight line. On the contrary, when the hydraulic oil is injected from the second hydraulic chamber 234 into the first hydraulic chamber 233, the piston 250 can be pushed to move inward in the inner cylinder 231, thereby driving the hydraulic shaft 240 to move inward along a straight line. In this embodiment, the control of the hydraulic oil can be controlled by a hydraulic pump.

[0036] In some embodiments of the utility model, the telescopic adjustment component 200 also includes a first pipeline 201, a second pipeline 202 and a suction sleeve 203; one end of the first pipeline 201 is connected to the first hydraulic chamber 233, and the other end is connected to the second pipeline 202, and a first one-way stop valve 204 is arranged on the first pipeline 201; the second pipeline 202 is connected to the second hydraulic chamber 234, and the other end is connected to the suction sleeve 203, and a second one-way stop valve 205 is arranged on the second pipeline 202; a plunger 206 is arranged in the suction sleeve 203.

[0037] Specifically, in the present embodiment, the telescopic adjustment assembly 200 includes a hydraulic cylinder 230, a hydraulic shaft 240, a piston 250, a first pipeline 201, a second pipeline 202 and a suction sleeve 203; wherein the hydraulic cylinder 230 includes an inner cylinder body 231 and an outer cylinder body 232, the inner cylinder body 231 divides the outer cylinder body 232 into a first hydraulic chamber 233 and a second hydraulic chamber 234, one end of the first pipeline 201 is connected to the first hydraulic chamber 233, and the other end is connected to the second pipeline 202, and a first one-way stop valve 204 is arranged on the first pipeline 201; the second pipeline 202 is connected to the second hydraulic chamber 234, and the other end is connected to the suction sleeve 203, a second one-way stop valve 205 is arranged on the second pipeline 202, and a plunger 206 is arranged in the suction sleeve 203. When the telescopic adjustment assembly 200 is in the extended state, the piston 206 is driven to reciprocate. Specifically, when the piston 206 is moved outward, the hydraulic oil enters the first pipeline 201 through the first one-way check valve 204 via the first hydraulic chamber 233. When the piston 206 is moved inward, the hydraulic oil enters the second hydraulic chamber 234 through the second one-way valve 202 via the second pipeline, thereby pushing the piston 250 to move linearly. In this embodiment, the contact area between the piston 206 and the hydraulic oil is much smaller than the contact area between the piston 250 and the hydraulic oil. Therefore, according to the Pascal principle that the pressure applied to any part in a closed system will be evenly transmitted to other parts of the entire system. A larger thrust can be provided by applying a smaller force, so that the self-moving tail can be stably supported. It can be understood that during this movement, the hydraulic oil required for the space generated by the movement of the piston 250 can be compensated by an external oil tank.

[0038] In some embodiments of the present utility model, the telescopic adjustment assembly 200 further includes a third pipeline 207, one end of the third pipeline 207 is connected to the first hydraulic chamber 233, and the other end is connected to the second hydraulic chamber 234, and a third one-way check valve 208 is arranged on the third pipeline 207. In this embodiment, under normal conditions, the conduction direction of the third one-way valve is: the first hydraulic chamber 233 is one-way conduction to the second hydraulic chamber 234; when the telescopic adjustment assembly 200 needs to be retracted, the third one-way check valve 208 is controlled to be opened, and through the design of this structure, the hydraulic oil can be quickly returned to the first hydraulic chamber 233 through the second hydraulic chamber 234. The rapid recovery of the telescopic adjustment assembly 200 saves working time.

[0039] In some embodiments of the utility model, a quick return pipe 260 and a trigger rod 261 are provided on the outer cylinder 232. The trigger rod 261 is inserted into the quick return pipe 260 and is threadedly connected to the quick return pipe 260. One end of the trigger rod 261 can abut against the third one-way stop valve 208 and control its opening. Specifically, in this embodiment, by rotating the trigger rod 261, the trigger rod 261 can be controlled to reciprocate along the axial direction of the quick return pipe 260. During the movement, the trigger rod 261 can abut against the third one-way stop valve 208 and control the one-way valve to open. Specifically, in this embodiment, the third one-way valve is provided with a steel ball and a spring. Under normal conditions, the steel ball can close the third pipeline 207 under the action of the elastic potential energy of the spring. In the open state, one end of the trigger rod 261 can abut against the steel ball to offset the elastic potential energy of the spring, thereby opening the third pipeline 207. Through the design of this structure, the hydraulic oil can be quickly returned to the first hydraulic chamber 233 through the second hydraulic chamber 234. The rapid recovery of the telescopic adjustment assembly 200 saves working time.

[0040] In some embodiments of the utility model, the first pipeline 201 is connected to the first hydraulic chamber 233 at a side close to the spherical bearing 220. In this embodiment, the telescopic adjustment assembly 200 is installed on the mounting seat 100 in a vertical manner, and the communication position between the first pipeline 201 and the first hydraulic chamber 233 is set at the lower end of the telescopic adjustment assembly 200. Through the design of this structure, the hydraulic oil in the first hydraulic chamber 233 can be fully introduced into the second hydraulic chamber 234.

[0041] In some embodiments of the present invention, the second pipeline 202 is connected to the second hydraulic chamber 234 at the end of the stroke of the piston 250. In this embodiment, the communication position of the second pipeline 202 and the second hydraulic chamber 234 is set at the end of the stroke of the piston 250. Through the design of this structure, it is possible to avoid the piston 250 covering the second pipeline 202 when moving.

[0042] In some embodiments of the utility model, a clamping plate 110 is provided on both sides of the mounting seat 100, and the connecting shaft 211 is rotatably connected to the mounting seat 100 through the clamping plate 110. In this embodiment, since the mounting seat 100 is relatively large in size, it is relatively difficult to fine-process the mounting seat 100. By providing the clamping plate 110, the processing cost can be saved by fine-processing the clamping plate 110.

[0043] In some embodiments of the utility model, ribs 120 are respectively provided on both sides of the mounting seat 100, mounting holes 121 are provided on the ribs 120, and fastening bolts 130 are provided on the mounting holes 121. In this embodiment, by providing the ribs 120, the structural strength of the mounting seat 100 can be improved, and the mounting seat 100 can be fixed on the tail of the self-propelled machine by the fastening bolts 130. In this embodiment, the ribs can be fixed on the mounting seat 100 by welding.

[0044] In some embodiments of the utility model, a positioning pin 140 is further provided on the mounting seat 100. In this embodiment, the mounting seat 100 needs to be fixedly connected to the self-moving tail, and ribs 120 are respectively provided on both sides of the mounting seat 100, and mounting holes 121 are provided on the ribs 120, and the mounting seat 100 is fixed to the self-moving tail by fastening bolts 130. However, since the weight of the self-moving tail is large, in order to avoid the failure of the fastening bolts 130, by providing the positioning pin 140, the positioning pin 140 can bear part of the weight, thereby increasing the service life of the fastening bolts 130.

[0045] The embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in the relevant technical field without departing from the purpose of the present invention.

Claims

1. A self-moving tail support leveling mechanism, characterized in that: include: A mounting seat (100), wherein the mounting seat (100) is provided with a receiving cavity (101), and the lower end of the mounting seat (100) is open; A telescopic adjustment component (200), wherein the telescopic adjustment component (200) is provided with a horizontal connection sleeve (210), and connecting shafts (211) are respectively provided on both sides of the horizontal connection sleeve (210); the upper end of the telescopic adjustment component (200) is rotatably connected to the mounting seat (100) via the connecting shaft (211), and the lower end of the telescopic adjustment component (200) is provided with a joint bearing (220); A track wheel assembly (300), the upper end of which is slidably disposed in the accommodating cavity (101) along a vertical direction; and the track wheel assembly (300) and the lower end of the telescopic adjustment assembly (200) are rotatably connected.

2. The self-moving tail support and leveling mechanism according to claim 1, characterized in that: The telescopic adjustment assembly (200) comprises a hydraulic cylinder (230), a hydraulic shaft (240) and a piston (250); the hydraulic cylinder (230) comprises an inner cylinder (231) and an outer cylinder (232); the inner cylinder (231) divides the outer cylinder (232) into a first hydraulic chamber (233) and a second hydraulic chamber (234); the piston (250) is slidably arranged in the second hydraulic chamber (234); one end of the hydraulic shaft (240) is fixedly connected to the piston (250), and the other end of the hydraulic shaft (240) is fixedly connected to the joint bearing (220).

3. The self-moving tail support and leveling mechanism according to claim 2, characterized in that: The telescopic adjustment assembly (200) further comprises a first pipeline (201), a second pipeline (202) and a suction sleeve (203); one end of the first pipeline (201) is connected to the first hydraulic chamber (233), and the other end is connected to the second pipeline (202); a first one-way check valve (204) is provided on the first pipeline (201); The second pipeline (202) is in communication with the second hydraulic chamber (234), and the other end is in communication with the suction sleeve (203); a second one-way check valve (205) is provided on the second pipeline (202); and a plunger (206) is provided in the suction sleeve (203).

4. The self-moving tail support and leveling mechanism according to claim 3, characterized in that: The telescopic adjustment assembly (200) further comprises a third pipeline (207), one end of the third pipeline (207) being connected to the first hydraulic chamber (233), and the other end of the third pipeline (207) being connected to the second hydraulic chamber (234), and a third one-way stop valve (208) being arranged on the third pipeline (207).

5. The self-moving tail support and leveling mechanism according to claim 4, characterized in that: The outer cylinder (232) is provided with a fast reflux pipe (260) and a trigger rod (261); the trigger rod (261) is inserted into the fast reflux pipe (260) and is threadedly connected to the fast reflux pipe (260); one end of the trigger rod (261) can abut against the third one-way stop valve (208) and control the opening thereof.

6. The self-moving tail support and leveling mechanism according to claim 3, characterized in that: The first pipeline (201) is connected to the first hydraulic chamber (233) at a side close to the spherical bearing (220).

7. The self-moving tail support and leveling mechanism according to claim 3, characterized in that: The second pipeline (202) is connected to the second hydraulic chamber (234) at the end of the stroke of the piston (250).

8. The self-moving tail support and leveling mechanism according to claim 7, characterized in that: Clamping plates (110) are respectively provided on both sides of the mounting seat (100), and the connecting shaft (211) is rotatably connected to the mounting seat (100) via the clamping plates (110).

9. The self-moving tail support and leveling mechanism according to claim 1, characterized in that: Ribs (120) are respectively provided on both sides of the mounting seat (100), mounting holes (121) are provided on the ribs (120), and fastening bolts (130) are provided on the mounting holes (121).

10. The self-moving tail support and leveling mechanism according to claim 1, characterized in that: The mounting seat (100) is also provided with a positioning pin (140).

Images