Mining semi-automatic drill jumbo

Abstract

The invention relates to a mining semi-automatic drill jumbo. Comprising a vehicle body, a driving assembly, a vehicle-mounted hydraulic system, a driving module, a multi-stage telescopic arm and a rock drilling mechanism, wherein the driving assembly and the vehicle-mounted hydraulic system are mounted on the vehicle body; the driving module is fixedly arranged on one side of the vehicle body; the multi-stage telescopic arm is detachably mounted on one side of the driving module and controlled by the vehicle-mounted hydraulic system; the working mode that one person drives and one person remotely controls the rock drilling distance and speed is adopted, the two workers are matched, the rock drilling distance and speed are reasonably controlled, deviation in the rock drilling process can be found in time, when a drill bit is cooled, the positioning assembly is inserted into a rock hole, the rock drilling mechanism keeps a stable posture, deviation caused by vibration of equipment is avoided, and the rock drilling efficiency is improved. And the drill bit and the anchor rod can be conveniently inserted into the same rock hole again for continuous operation.

Description

Technical Field

[0001] This invention relates to the field of rock drilling vehicle technology, specifically to a semi-automatic rock drilling rig for mining. Background Technology

[0002] When operating a rock drilling rig by a single person, the operator must simultaneously manage multiple tasks such as equipment operation, rock drilling parameter adjustment, and deviation monitoring. This distraction can easily lead to inaccurate control of the drilling distance, delayed speed adjustment, and difficulty in detecting deviations during the drilling process in real time. Once a borehole deviation occurs, not only must the equipment be readjusted, but the borehole may also be scrapped, severely impacting work efficiency. In the two-person collaborative mode, the two workers must cooperate in the same operating space. Due to the limitations of the equipment operating area, communication and coordination are delayed, making it difficult to achieve precise control of the drilling distance and speed efficiently, and the timeliness of deviation detection and correction is poor.

[0003] Secondly, during rock drilling, the drill bit generates a large amount of heat due to continuous friction with the rock, requiring periodic shutdowns for cooling. Existing rock drilling rigs lack effective attitude stabilization mechanisms during the drill bit cooling phase: vibrations generated by the equipment's operation can easily cause the drilling mechanism to shift, making it difficult for the cooled drill bit to accurately align with the original rock hole. If continued operation is required, the rock hole position must be repositioned, increasing the number of steps and potentially causing anchor bolts to fail to insert smoothly into the original rock hole due to secondary positioning errors, further extending the work cycle and even causing additional damage to the rock structure, affecting the safety and stability of subsequent support operations. Summary of the Invention

[0004] In order to solve the above-mentioned problems in the existing technology, the present invention aims to provide a semi-automatic rock drilling rig for mining.

[0005] The technical solution adopted in this invention is as follows: A semi-automatic rock drilling rig for mining includes a vehicle body, a drive assembly and an on-board hydraulic system mounted on the vehicle body, a driving module fixedly mounted on one side of the vehicle body, a multi-stage telescopic boom detachably mounted on one side of the driving module and controlled by the on-board hydraulic system, and a rock drilling mechanism mounted on the multi-stage telescopic boom. The rock drilling mechanism includes a bearing rail connected to the multi-stage telescopic arm, a mounting base slidably disposed on the bearing rail, a drive motor detachably mounted on the mounting base, an anchor rod connected to the output shaft of the drive motor via a coupling, a drill bit fixedly disposed at the end of the anchor rod away from the drive motor, and a positioning assembly installed between the drill bit and the anchor rod. The positioning assembly includes a movable sleeve sleeved around the anchor bolt, a sliding sleeve slidably disposed inside the movable sleeve, and multiple positioning plates connected to the sliding sleeve via a rotating rod. The sliding sleeve is controlled to slide relative to the movable sleeve by the action of the drill bit being pulled out of the rock hole. After the sliding sleeve drives the positioning plates to converge via the rotating rod, it drives the positioning assembly to insert into the rock hole. When the drill bit cools down, the positioning assembly is used to maintain the rock drilling mechanism in a stable posture and assist the rock drilling mechanism in re-inserting into the rock hole.

[0006] As a preferred embodiment of the present invention, the rock drilling mechanism further includes a fixed pulley rotatably disposed at one end of the bearing rail. The fixed pulley is located on the side of the bearing rail near the mounting base. The mounting base and the fixed pulley are connected by multiple steel cables. The winch is driven to rotate by the vehicle-mounted hydraulic system to control the movement of the mounting base relative to the bearing rail, thereby realizing the feed of the anchor rod during the rock drilling process.

[0007] As a preferred embodiment of the present invention, a fixed frame is fixedly provided at the end of the bearing rail away from the fixed pulley, the sliding seat is connected to the bearing rail through a control cylinder, the fixed frame and the sliding seat are used to support the anchor rod, and a wire harness clamp is fixedly provided on one side of the bearing rail.

[0008] As a preferred embodiment of the present invention, the positioning assembly further includes a fixing plate fixedly connected to the fixing frame, and a positioning cylinder is provided on the side of the fixing plate away from the fixing frame. The cylinder barrel of the positioning cylinder is fixedly connected to the fixing plate, and the piston rod of the positioning cylinder is connected to the movable sleeve.

[0009] As a preferred embodiment of the present invention, the positioning plate includes an insertion hole portion and a clamping portion integrally formed, and a connecting rod fixedly disposed at one end of the clamping portion and hinged to one end of the rotating rod. The insertion hole portion is used to insert into the rock hole, and the clamping portion is used to clamp the drill bit. The insertion hole portion and the clamping portion realize the positioning of the drill bit after it is separated from the rock hole.

[0010] As a preferred embodiment of the present invention, the movable sleeve includes a sleeve body sleeved around the anchor rod, a mounting flange fixedly disposed at one end of the sleeve body and connected to the piston rod of the positioning cylinder, and a sliding groove formed on the periphery of the sleeve body for supporting the sliding of the sliding sleeve.

[0011] As a preferred embodiment of the present invention, the movable sleeve further includes a fixing rod fixedly disposed at the end of the sleeve body away from the mounting flange, a fixing ring fixedly disposed at the end of the fixing rod away from the mounting flange, and a through hole disposed on the fixing ring and slidably connected to the connecting rod; the connecting rod passes through the through hole.

[0012] As a preferred embodiment of the present invention, the sliding sleeve includes a plurality of snap-fit ​​portions slidably connected to the sliding groove, a connecting portion for connecting the plurality of snap-fit ​​portions and located inside the sleeve body, and an extension portion fixedly disposed on the snap-fit ​​portions and hinged to the end of the rotating rod away from the connecting rod.

[0013] As a preferred embodiment of the present invention, a rubber washer is provided inside the sliding sleeve, an alignment groove is provided on the outer side of the rubber washer, an installation groove is provided on the inner wall of the sliding sleeve, a retaining ring is provided between the installation groove and the alignment groove, the installation groove, the alignment groove and the retaining ring cooperate, and the inner wall of the rubber washer forms a friction part, the shape of the friction part being adapted to the shape of the drill bit.

[0014] As a preferred embodiment of the present invention, a spring ring is provided on the periphery of the movable sleeve, and a washer is fixed at each end of the spring ring, with the two washer rings respectively abutting against the extension and the mounting flange.

[0015] The beneficial effects of this invention are as follows: This invention is a semi-automatic rock drilling rig for mining. It adopts an operation mode of one person driving and one person remotely controlling. Two workers cooperate to reasonably control the drilling distance and speed, and can detect deviations in the drilling process in a timely manner. In addition, when the drill bit is cooling, the positioning component is inserted into the rock hole to keep the rock drilling mechanism in a stable posture and prevent it from shifting due to equipment vibration. This makes it convenient for the drill bit and anchor rod to be inserted into the same rock hole again to continue the operation. Attached Figure Description

[0016] The present invention will now be described in further detail with reference to the accompanying drawings and specific implementation methods.

[0017] Figure 1 This is a schematic diagram of the structure of the present invention (rock drill not installed); Figure 2 This is the present invention. Figure 1 A schematic diagram of the structure of the rock drilling mechanism in conjunction with the rock drilling machine; Figure 3 This is the present invention. Figure 2 A schematic diagram of the positioning component structure; Figure 4 This is the present invention. Figure 3 A schematic diagram of the exploded structure; Figure 5 This is the present invention. Figure 4 A magnified schematic diagram of part of the structure. Detailed Implementation

[0018] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided below.

[0019] Combination Figures 1-5 A semi-automatic rock drilling rig for mining includes a vehicle body 11, a drive assembly 12 and an on-board hydraulic system 13 mounted on the vehicle body 11, a driving module 14 fixedly mounted on one side of the vehicle body 11, a multi-stage telescopic boom 15 detachably mounted on one side of the driving module 14 and controlled by the on-board hydraulic system 13, and a rock drilling mechanism 16 mounted on the multi-stage telescopic boom 15. One worker sits in the driving module 14 to drive the vehicle body 11 to the construction area, while another worker carries an operation box and remotely controls the rig from behind a shelter. The two workers cooperate to reasonably control the drilling distance and speed and can promptly detect deviations during the drilling process.

[0020] The rock drilling mechanism 16 includes a support rail 18 connected to the multi-stage telescopic boom 15, a mounting base 20 slidably mounted on the support rail 18, a drive motor 24 detachably mounted on the mounting base 20, an anchor rod 25 connected to the output shaft of the drive motor 24 via a coupling, a drill bit 27 fixedly mounted on the end of the anchor rod 25 away from the drive motor 24, and a positioning assembly 26 mounted between the drill bit 27 and the anchor rod 25. The multi-stage telescopic boom 15 can control the support rail 18 to move to a designated working position by adjusting the extension and angle between its sections. The rock drill includes a rotating part controlled by the drive motor 24, an impact part controlled by a winch, and a side water injection system. The rotating part drives the gearbox to increase torque and reduce the speed of the drill bit by the hydraulic motor. The impact part is responsible for energy conversion, and the output energy is transferred to the rock through the anchor rod and the drill bit to achieve the purpose of breaking the rock. The side water injection system provides cooling and lubrication during the rock drilling process to ensure the efficient operation of the rock drill.

[0021] The positioning component 26 includes a movable sleeve 34 sleeved around the anchor rod 25, a sliding sleeve 33 slidably disposed inside the movable sleeve 34, and multiple positioning plates 32 connected to the sliding sleeve 33 via a rotating rod 28. The sliding sleeve 33 slides relative to the movable sleeve 34 by the action of the drill bit 27 being pulled out of the rock hole. After the sliding sleeve 33 drives the positioning plates 32 to converge via the rotating rod 28, it drives the positioning component 26 to insert into the rock hole. When the drill bit 27 cools down, the positioning component 26 maintains a stable posture for the rock drilling mechanism 16 and assists the rock drilling mechanism 16 in re-inserting into the rock hole. The positioning component 26 inserts into the rock hole when the drill bit 27 cools down, preventing the rock drilling mechanism 16 from shifting due to equipment vibration, improving the accuracy of subsequent operations on the same rock hole, reducing the time spent on repeated positioning, and improving work efficiency.

[0022] Advantageously, the rock drilling mechanism 16 also includes a fixed pulley 21 rotatably disposed at one end of the support rail 18. The fixed pulley 21 is located on the side of the support rail 18 near the mounting base 20. The mounting base 20 and the fixed pulley 21 are connected by a multi-strand steel cable. The winch is driven by the vehicle-mounted hydraulic system 13 to rotate and control the movement of the mounting base 20 relative to the support rail 18, thereby realizing the feed of the anchor bolt 25 during the rock drilling process. The winch can move the mounting base 20 forward and backward by controlling the multi-strand steel cable.

[0023] Advantageously, a fixed frame 17 is fixedly provided at the end of the bearing rail 18 away from the fixed pulley 21, and the sliding seat 23 is connected to the bearing rail 18 through a control cylinder 22. The fixed frame 17 and the sliding seat 23 are used to support the anchor rod 25, and a wire harness clamp 19 is fixedly provided on one side of the bearing rail 18. A bearing ring is provided at the center of both the fixed frame 17 and the sliding seat 23, and the bearing ring allows the anchor rod 25 and the drill bit 27 to rotate and slide relative to the fixed frame 17 and the sliding seat 23.

[0024] Advantageously, the positioning assembly 26 further includes a fixing plate 31 fixedly connected to the fixing frame 17. A positioning cylinder 29 is provided on the side of the fixing plate 31 away from the fixing frame 17. The cylinder barrel of the positioning cylinder 29 is fixedly connected to the fixing plate 31, and the piston rod of the positioning cylinder 29 is connected to the moving sleeve 34. The positioning cylinder 29 is driven by an on-board hydraulic system and can cooperate with a winch to achieve precise linkage with the movement of the anchor bolt 25 during feeding and retraction.

[0025] Advantageously, the positioning plate 32 includes an integrally formed insertion hole portion 37 and a clamping portion 38, and a connecting rod 36 fixedly disposed at one end of the clamping portion 38 and hinged to one end of the rotating rod 28. The insertion hole portion 37 is used to insert into the rock hole, and the clamping portion 38 is used to clamp the drill bit 27. The insertion hole portion 37 and the clamping portion 38 realize the positioning of the drill bit 27 after it is separated from the rock hole. The inner shape of the clamping portion 38 is adapted to the outer wall shape of the drill bit 27, and the inner and outer sides of the insertion hole portion 37 are smooth, which can form a fit with the inner wall of the rock hole.

[0026] Advantageously, the movable sleeve 34 includes a sleeve body 44 sleeved around the anchor rod 25, a mounting flange 43 fixedly disposed at one end of the sleeve body 44 and connected to the piston rod of the positioning cylinder 29, and a groove 42 formed around the sleeve body 44 to support the sliding sleeve 33. The groove 42 is hollowed out in the side wall of the sleeve body 44, and when the movable sleeve 34 and the sliding sleeve 33 are not allowed to slide relative to each other, the positioning cylinder 29 will drive them to move synchronously.

[0027] Advantageously, the movable sleeve 34 further includes a fixing rod 41 fixedly disposed at the end of the sleeve body 44 away from the mounting flange 43, a fixing ring 39 fixedly disposed at the end of the fixing rod 41 away from the mounting flange 43, and a through hole 40 disposed on the fixing ring 39 and slidably connected to the connecting rod 36; the connecting rod 36 passes through the through hole 40. The through hole 40 allows the positioning plate 32 to move only radially.

[0028] Advantageously, the sliding sleeve 33 includes a plurality of snap-fit ​​parts 47 slidably connected to the slide groove 42, a connecting part 45 for connecting the plurality of snap-fit ​​parts 47 and located inside the sleeve body 44, and an extension part 46 fixedly disposed on the snap-fit ​​parts 47 and hinged to the end of the rotating rod 28 away from the connecting rod 36. The connecting part 45 enables the plurality of snap-fit ​​parts 47 to move synchronously, and through the transmission of the rotating rod 28, it can drive the plurality of positioning plates 32 to move synchronously.

[0029] Advantageously, a rubber washer 35 is provided inside the sliding sleeve 33. An alignment groove 49 is provided on the outer side of the rubber washer 35, and an installation groove 48 is provided on the inner wall of the sliding sleeve 33. A retaining ring is provided between the installation groove 48 and the alignment groove 49. The installation groove 48, the alignment groove 49, and the retaining ring cooperate, and the inner wall of the rubber washer 35 forms a friction part 50. The shape of the friction part 50 is adapted to the shape of the drill bit 27. The rubber washer 35 is a consumable and needs to be replaced periodically after a certain period of use. The retaining ring allows the rubber washer 35 to move synchronously within the sliding sleeve 33 after installation, without affecting the rotation of the rubber washer 35 relative to the sliding sleeve 33. The anchor rod 25 and the drill bit 27 have different specifications, materials, and structures. The frictional force generated when the anchor rod 25 and the rubber washer 35 move relative to each other is insufficient to overcome the elastic force of the spring coil 30. Therefore, the positioning plate 32 tends to maintain a stable divergent posture when diverging.

[0030] Advantageously, the movable sleeve 34 is provided with a spring ring 30 around its periphery, and a washer is fixed at each end of the spring ring 30. The two washer rings respectively abut against the extension 46 and the mounting flange 43. The spring ring 30 allows the positioning plate 32 to instantly disperse after leaving the rock hole, and keeps the positioning plate 32 in a dispersed state when the rock drill is working normally, without interfering with the normal operation of the anchor rod 25 and the drill bit 27.

[0031] Working principle of this invention: The multi-stage telescopic boom 15 is started using the vehicle-mounted hydraulic system 13, the rock drilling mechanism 16 is adjusted to a suitable construction position, and the remote-controlled drive motor 24 is started. The output shaft of the drive motor 24 controls the rotation of the anchor rod 25 and the drill bit 27. At the same time, the vehicle-mounted hydraulic system 13 controls the winch to wind the steel cable, causing the mounting base 20 and the drive motor 24 to slide along the bearing rail 18, controlling the feed of the anchor rod 25 and the drill bit 27. After the drill bit 27 contacts the rock, rock drilling begins. During this process, the control cylinder 22 controls the sliding seat 23 to move adaptively, keeping the sliding seat 23 at the midpoint of the part of the anchor rod 25 exposed outside the rock.

[0032] After the drill bit 27 has been working for a certain period of time, the operation is paused. The vehicle-mounted hydraulic system 13 controls the winch to wind the steel rope, causing the mounting base 20 and the drive motor 24 to slide along the bearing rail 18, so that the drill bit 27 and the anchor rod 25 retract. The drill bit 27 retracts to the position of the fixed frame 17 for cooling. The cooling method can be water cooling or other common cooling methods.

[0033] During the retraction of the drill bit 27, the anchor rod 25 and the drill bit 27 slide against the positioning component 26. The anchor rod 25 and the drill bit 27 pass by the rubber washer 35 one after the other. The friction between the anchor rod 25 and the rubber washer 35 is small and does not change the state of the positioning component 26. When the drill bit 27 passes the rubber washer 35, the friction causes the drill bit 27 to move along with the rubber washer 35. The sliding sleeve 33 moves along with the rubber washer 35 and slides relative to the moving sleeve 34. The spring ring 30 is compressed. The sliding sleeve 33 drives the multiple positioning plates 32 to gather together through the rotating rod 28. After the multiple positioning plates 32 gather to the clamping part 38 to clamp the drill bit 27, they cannot continue to gather together. The drill bit 27 continues to retract. At this time, the positioning cylinder 29 is ready. When the drill bit 27 leaves the rock hole, the positioning cylinder 29 controls its piston rod to extend, driving the moving sleeve 34 and the gathered positioning plates 32 to be pushed out to the insertion part 37 and inserted into the rock hole.

[0034] The drill bit 27 retracts between the fixed plate 31 and the mounting flange 43 for cooling. At this time, the positioning plate 32 is inserted into the rock hole, and the rock drilling mechanism 16 will not shift due to equipment vibration.

[0035] When drill bit 27 resumes operation, the on-board hydraulic system 13 controls the winch to wind the steel rope, causing the mounting base 20 and drive motor 24 to slide along the bearing rail 18, thus feeding the anchor bolt 25 and drill bit 27. During this process, because the positioning plate 32 is constrained by the inner wall of the rock hole, the movement of drill bit 27 cannot change the state of positioning assembly 26. When drill bit 27 inserts into the rock hole, positioning cylinder 29 is activated to control its piston rod to reset, driving the moving sleeve 34 and the converged positioning plate 32 to be pulled out. When the positioning plate 32 leaves the rock hole, under the action of spring coil 30, spring coil 30 resets, causing the sliding sleeve 33 to move relative to the moving sleeve 34, causing the multiple positioning plates 32 to disperse and maintain this state. At this time, drive motor 24 is activated, allowing anchor bolt 25 and drill bit 27 to rotate normally again for rock drilling operations.

[0036] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A semi-automatic rock drilling rig for mining, characterized in that: It includes a vehicle body, a drive assembly and an onboard hydraulic system mounted on the vehicle body, a driving module fixedly mounted on one side of the vehicle body, a multi-stage telescopic boom detachably mounted on one side of the driving module and controlled by the onboard hydraulic system, and a rock drilling mechanism mounted on the multi-stage telescopic boom. The rock drilling mechanism includes a bearing rail connected to the multi-stage telescopic arm, a mounting base slidably disposed on the bearing rail, a drive motor detachably mounted on the mounting base, an anchor rod connected to the output shaft of the drive motor via a coupling, a drill bit fixedly disposed at the end of the anchor rod away from the drive motor, and a positioning assembly installed between the drill bit and the anchor rod. The positioning assembly includes a movable sleeve sleeved around the anchor bolt, a sliding sleeve slidably disposed inside the movable sleeve, and multiple positioning plates connected to the sliding sleeve via a rotating rod. The sliding sleeve is controlled to slide relative to the movable sleeve by the action of the drill bit being pulled out of the rock hole. After the sliding sleeve drives the positioning plates to converge via the rotating rod, it drives the positioning assembly to insert into the rock hole. When the drill bit cools down, the positioning assembly is used to maintain the rock drilling mechanism in a stable posture and assist the rock drilling mechanism in re-inserting into the rock hole.

2. The semi-automatic rock drilling rig for mining according to claim 1, characterized in that: The rock drilling mechanism also includes a fixed pulley rotatably mounted at one end of the bearing rail. The fixed pulley is located on the side of the bearing rail near the mounting base. The mounting base and the fixed pulley are connected by multiple steel cables. The winch is driven by the vehicle-mounted hydraulic system to rotate and control the movement of the mounting base relative to the bearing rail, thereby realizing the feed of the anchor rod during the rock drilling process.

3. A semi-automatic rock drilling rig for mining according to claim 2, characterized in that: A fixed frame is fixedly provided at the end of the bearing rail away from the fixed pulley. The sliding seat is connected to the bearing rail through a control cylinder. The fixed frame and the sliding seat are used to support the anchor rod. A wire harness clamp is fixedly provided on one side of the bearing rail.

4. A semi-automatic rock drilling rig for mining according to claim 1, characterized in that: The positioning assembly also includes a fixing plate fixedly connected to the fixing frame. A positioning cylinder is provided on the side of the fixing plate away from the fixing frame. The cylinder barrel of the positioning cylinder is fixedly connected to the fixing plate, and the piston rod of the positioning cylinder is connected to the movable sleeve.

5. A semi-automatic rock drilling rig for mining according to claim 4, characterized in that: The positioning plate includes an integral insertion hole and a clamping part, and a connecting rod fixedly disposed at one end of the clamping part and hinged to one end of the rotating rod. The insertion hole is used to insert into the rock hole, and the clamping part is used to clamp the drill bit. The insertion hole and the clamping part realize the positioning of the drill bit after it is separated from the rock hole.

6. A semi-automatic rock drilling rig for mining according to claim 4, characterized in that: The movable sleeve includes a sleeve body sleeved around the anchor rod, a mounting flange fixedly disposed at one end of the sleeve body and connected to the piston rod of the positioning cylinder, and a sliding groove formed on the periphery of the sleeve body to support the sliding of the sliding sleeve.

7. A semi-automatic rock drilling rig for mining according to claim 6, characterized in that: The movable sleeve further includes a fixed rod fixedly disposed at the end of the sleeve body away from the mounting flange, a fixed ring fixedly disposed at the end of the fixed rod away from the mounting flange, and a through hole disposed on the fixed ring and slidably connected to the connecting rod; the connecting rod passes through the through hole.

8. A semi-automatic rock drilling rig for mining according to claim 6, characterized in that: The sliding sleeve includes multiple snap-fit ​​parts that are slidably connected to the slide groove, a connecting part for connecting the multiple snap-fit ​​parts and located inside the sleeve body, and an extension part that is fixedly disposed on the snap-fit ​​parts and hinged to the end of the rotating rod away from the connecting rod.

9. A semi-automatic rock drilling rig for mining according to claim 4, characterized in that: The sliding sleeve is provided with a rubber washer, the outer side of the rubber washer is provided with an alignment groove, the inner wall of the sliding sleeve is provided with an installation groove, and a retaining ring is provided between the installation groove and the alignment groove. The installation groove, the alignment groove and the retaining ring cooperate, and the inner wall of the rubber washer forms a friction part. The shape of the friction part is adapted to the shape of the drill bit.

10. A semi-automatic rock drilling rig for mining according to claim 8, characterized in that: The movable sleeve is provided with a spring ring on its periphery, and a washer is fixed at each end of the spring ring. The two washer rings abut against the extension and the mounting flange, respectively.

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