Self-lubricating device for slideway hole of coal mine high-pressure pump

Abstract

The utility model provides a coal mine high-pressure pump slideway hole self-lubricating device which comprises a crankcase, three slideway hole bodies are arranged in an inner cavity of the crankcase, three plunger connecting rods are arranged on the left side of the inner cavity of the crankcase, plunger bodies are arranged on the right sides of the plunger connecting rods, a pump head is arranged on the right side of the crankcase, and a mounting plate is fixedly mounted on the left side of the top of the crankcase. A mounting assembly is movably mounted on the left side of an inner cavity of the mounting plate, a lubricating oil tank is detachably mounted at the top of the mounting plate, and limiting plates are fixedly mounted at four corners of the bottom of the lubricating oil tank. Through cooperative use of the lubricating oil tank, the connecting shell, the connecting sleeve and the lubricating assembly, lubricating oil can be automatically added into the high-pressure pump slide way hole, friction of the plunger body in the slide way hole body can be effectively reduced by automatically adding the lubricating oil, and therefore the service life of parts is prolonged, and abrasion is reduced; and the stable operation of the plunger body in the slideway hole body can be ensured by automatically adding the lubricating oil, and the output stability and reliability of the pump are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of slideway holes of high-pressure pumps, in particular to a self-lubricating device for slideway holes of high-pressure pumps in coal mines. Background Art

[0002] The slideway hole of the coal mine high-pressure pump is a key structure inside the high-pressure pump. It is mainly composed of the slideway hole, sliding parts (such as pistons, crankshafts, etc.) and related support and sealing parts. The slideway hole provides a movement track for the sliding parts to ensure that they can move smoothly and stably while reducing friction and wear.

[0003] During long-term use, the existing high-pressure pump slide hole cannot automatically add lubricating oil to the inside of the high-pressure pump slide hole, and the staff needs to add it through a cumbersome process. If the slide hole is not properly lubricated, the friction of the piston or plunger will increase during movement, which may cause premature wear and damage of the components. Lack of lubrication may cause unstable movement of the plunger, affecting the output stability and reliability of the pump.

[0004] Therefore, we made improvements to this and proposed a self-lubricating device for the slideway hole of a coal mine high-pressure pump. Utility Model Content

[0005] The purpose of the utility model is to solve the problem that the existing high-pressure pump slide hole cannot automatically add lubricating oil to the inside of the high-pressure pump slide hole after long-term use, and the staff needs to add it through a cumbersome process. If the slide hole fails to be properly lubricated, the friction of the piston or plunger will increase during movement, which may cause premature wear and damage of the components. Lack of lubrication may cause unstable movement of the plunger, affecting the output stability and reliability of the pump.

[0006] In order to achieve the above-mentioned invention object, the utility model provides the following technical solutions:

[0007] A self-lubricating device for the slideway hole of a coal mine high-pressure pump is used to improve the above problems.

[0008] The specific application is as follows:

[0009] It includes a crankcase, the inner cavity of the crankcase is provided with three slide hole bodies, three plunger connecting rods are provided on the left side of the inner cavity of the crankcase, a plunger body is provided on the right side of the plunger connecting rod, a pump head is provided on the right side of the crankcase, a mounting plate is fixedly installed on the left side of the top of the crankcase, a mounting assembly is movably installed on the left side of the inner cavity of the mounting plate, a lubricating oil tank is detachably installed on the top of the mounting plate, limiting plates are fixedly installed on the four corners of the bottom of the lubricating oil tank, side plates are fixedly installed on the front and rear sides of the top of the mounting plate, a connecting shell is fixedly installed on the right side of the lubricating oil tank, a connecting sleeve is threadedly connected to the right side of the connecting shell, and the right side of the connecting sleeve is connected to the lubrication assembly.

[0010] By using the lubricating oil tank, connecting shell, connecting sleeve and lubrication assembly in coordination, lubricating oil can be automatically added to the inside of the slideway hole of the high-pressure pump. Automatic addition of lubricating oil can effectively reduce the friction of the plunger body in the slideway hole, thereby extending the service life of the components and reducing wear. Automatic addition of lubricating oil can ensure the stable operation of the plunger body in the slideway hole and improve the output stability and reliability of the pump.

[0011] As a preferred embodiment of the self-lubricating device for the slide hole of a coal mine high-pressure pump provided by the utility model, the mounting assembly includes a bidirectional screw rod, which is movably mounted on the left side of the inner cavity of the mounting plate, and a rotating disk is fixedly mounted on the left side of the bidirectional screw rod, and both sides of the surface of the bidirectional screw rod are threadedly connected with fixed blocks, and the front and rear sides of the fixed blocks are fixedly mounted with movable wheels, and the opposite sides of the two movable wheels are movably mounted with inclined blocks, and the opposite sides of the two inclined blocks are fixedly mounted with baffles, and the opposite sides of the two baffles are fixedly mounted with clamping blocks, and the opposite sides of the two baffles are fixedly mounted with two springs, and the side of the spring close to the mounting plate is fixedly connected to the mounting plate.

[0012] As a preferred embodiment of the self-lubricating device for the slideway hole of a coal mine high-pressure pump provided by the utility model, a limiting block is fixedly installed on the bottom of the fixed block, a limiting shell is arranged on the surface of the limiting block, and the limiting shell is fixedly connected to the mounting plate on one side close to the mounting plate.

[0013] As a preferred embodiment of the coal mine high-pressure pump slide hole self-lubricating device provided by the utility model, sliding blocks are fixedly installed on both sides of the baffle, a sliding rod is slidably installed in the inner cavity of the sliding block, and the sliding rod is fixedly connected to the mounting plate on the side close to the mounting plate.

[0014] As a preferred embodiment of the coal mine high-pressure pump slide hole self-lubricating device provided by the utility model, the lubrication assembly includes an oil inlet pipe, the oil inlet pipe is connected to the right side of the connecting sleeve, the right side of the oil inlet pipe is connected to a micro oil pump, the side of the micro oil pump close to the crankcase is fixedly connected to the crankcase, the right side of the micro oil pump is connected to six oil outlet pipes, the bottom of the oil outlet pipe is connected to a connecting pipe, and the opposite sides of the two connecting pipes are connected to nozzles.

[0015] As a preferred embodiment of the coal mine high-pressure pump slide hole self-lubricating device provided by the utility model, two positioning plates are fixedly installed on the front and rear sides of the mounting plate, and the positioning plate is fixedly connected to the crankcase on the side close to the crankcase.

[0016] As a preferred embodiment of the self-lubricating device for the slideway hole of a coal mine high-pressure pump provided by the utility model, a fixing ring is sleeved on the surface of the connecting shell, and a side of the fixing ring close to the lubricating oil tank is fixedly connected to the lubricating oil tank.

[0017] As a preferred embodiment of the self-lubricating device for the slideway hole of a coal mine high-pressure pump provided by the utility model, the surface of the connecting sleeve is provided with screw strips, and the inner cavity of the connecting shell is provided with screw grooves.

[0018] Compared with the prior art, the utility model has the following beneficial effects: through the coordinated use of the lubricating oil tank, the connecting shell, the connecting sleeve and the lubrication assembly, lubricating oil can be automatically added to the inside of the slide hole of the high-pressure pump. The automatic addition of lubricating oil can effectively reduce the friction of the plunger body in the slide hole body, thereby extending the service life of the components and reducing wear. The automatic addition of lubricating oil can ensure the stable operation of the plunger body in the slide hole body, and improve the output stability and reliability of the pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic diagram of the structure of the self-lubricating device for the slideway hole of a high-pressure pump in a coal mine provided in this application;

[0020] Figure 2 This is a schematic diagram of the front and cross-sectional view of the structure of the self-lubricating device for the slideway hole of a coal mine high-pressure pump provided in this application;

[0021] Figure 3 A top view and cross-sectional diagram of a crankcase of a self-lubricating device for a slideway hole of a coal mine high-pressure pump provided in the present application;

[0022] Figure 4 A schematic diagram of a front and cross-sectional view of a mounting plate of a self-lubricating device for a slideway hole of a high-pressure pump in a coal mine provided in the present application;

[0023] Figure 5 A schematic diagram of the main view of the connection shell of the self-lubricating device for the slideway hole of a coal mine high-pressure pump provided in this application;

[0024] Figure 6 A schematic side view of the installation assembly of the self-lubricating device for the slideway hole of a high-pressure pump in a coal mine provided in this application;

[0025] Figure 7 This is a schematic front view of the lubrication assembly of the self-lubricating device for the slideway hole of a coal mine high-pressure pump provided in this application.

[0026] Indicated in the figure:

[0027] 1. Crankcase; 2. Slideway hole; 3. Plunger connecting rod; 4. Plunger body; 5. Pump head; 6. Mounting plate; 7. Mounting assembly; 701. Bidirectional screw; 702. Rotating plate; 703. Fixed block; 704. Movable wheel; 705. Inclined block; 706. Baffle; 707. Block; 708. Spring; 709. Limit block; 710. Limit shell; 711. Sliding block; 712. Sliding rod; 8. Lubricating oil tank; 9. Limit plate; 10. Side plate; 11. Connecting shell; 12. Connecting sleeve; 13. Lubricating assembly; 1301. Oil inlet pipe; 1302. Micro oil pump; 1303. Oil outlet pipe; 1304. Connecting pipe; 1305. Spray nozzle; 14. Positioning plate; 15. Fixed ring; 16. Screw strip; 17. Screw groove. DETAILED DESCRIPTION

[0028] To make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be described clearly and completely in conjunction with the accompanying drawings. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments.

[0029] Therefore, the following detailed description of the embodiments of the present invention is not intended to limit the scope of the present invention to be protected, but merely represents some embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features and technical solutions in the embodiments may be combined with each other.

[0031] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0032] In the description of the present utility model, it should be noted that the orientation or position relationship indicated by the terms "upper", "lower", etc. is based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the invention product is usually placed when in use, or the orientation or position relationship commonly understood by those skilled in the art. Such terms are only for the convenience of describing the present utility model and simplifying the description, and do not indicate or imply 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 utility model. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0033] As described in the background technology, the existing high-pressure pump slide hole cannot automatically add lubricating oil to the inside of the high-pressure pump slide hole after long-term use, and the staff needs to add it through a cumbersome process. If the slide hole is not properly lubricated, the friction of the piston or plunger will increase during movement, which may cause premature wear and damage of the components. Lack of lubrication may cause unstable movement of the plunger, affecting the output stability and reliability of the pump.

[0034] In order to solve this technical problem, the utility model provides a self-lubricating device for a slideway hole of a high-pressure pump in a coal mine.

[0035] Specifically, please refer to Figure 1-7 The self-lubricating device of the slide hole of the coal mine high-pressure pump specifically includes: a crankcase 1, an inner cavity of the crankcase 1 is provided with three slide hole bodies 2, three plunger connecting rods 3 are provided on the left side of the inner cavity of the crankcase 1, a plunger body 4 is provided on the right side of the plunger connecting rod 3, a pump head 5 is provided on the right side of the crankcase 1, a mounting plate 6 is fixedly installed on the left side of the top of the crankcase 1, a mounting assembly 7 is movably installed on the left side of the inner cavity of the mounting plate 6, a lubricating oil tank 8 is detachably installed on the top of the mounting plate 6, limiting plates 9 are fixedly installed on the four corners of the bottom of the lubricating oil tank 8, side plates 10 are fixedly installed on the front and rear sides of the top of the mounting plate 6, a connecting shell 11 is fixedly installed on the right side of the lubricating oil tank 8, a connecting sleeve 12 is threadedly connected to the right side of the connecting shell 11, and a lubricating assembly 13 is connected to the right side of the connecting sleeve 12.

[0036] By using the lubricating oil tank 8, the connecting shell 11, the connecting sleeve 12 and the lubricating assembly 13 in coordination, lubricating oil can be automatically added to the inside of the slide hole of the high-pressure pump. Automatic addition of lubricating oil can effectively reduce the friction of the plunger body 4 in the slide hole body 2, thereby extending the service life of the components and reducing wear. Automatic addition of lubricating oil can ensure the stable operation of the plunger body 4 in the slide hole body 2, thereby improving the output stability and reliability of the pump.

[0037] In order to enable those skilled in the art to better understand the solution of the utility model, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the accompanying drawings.

[0038] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features and technical solutions in the embodiments may be combined with each other.

[0039] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0040] Example 1

[0041] Please refer to Figure 1-7 A self-lubricating device for a slide hole of a high-pressure pump in a coal mine comprises a crankcase 1, an inner cavity of the crankcase 1 is provided with three slide hole bodies 2, three plunger connecting rods 3 are provided on the left side of the inner cavity of the crankcase 1, a plunger body 4 is provided on the right side of the plunger connecting rod 3, a pump head 5 is provided on the right side of the crankcase 1, a mounting plate 6 is fixedly installed on the left side of the top of the crankcase 1, a mounting assembly 7 is movably installed on the left side of the inner cavity of the mounting plate 6, a lubricating oil tank 8 is detachably installed on the top of the mounting plate 6, limiting plates 9 are fixedly installed on the four corners of the bottom of the lubricating oil tank 8, side plates 10 are fixedly installed on the front and rear sides of the top of the mounting plate 6, a connecting shell 11 is fixedly installed on the right side of the lubricating oil tank 8, a connecting sleeve 12 is threadedly connected to the right side of the connecting shell 11, and a lubricating assembly 13 is connected to the right side of the connecting sleeve 12. The mounting assembly 7 includes a bidirectional screw rod 701, which is movably mounted on the left side of the inner cavity of the mounting plate 6, a rotating disk 702 is fixedly mounted on the left side of the bidirectional screw rod 701, and a fixed block 703 is threadedly connected to both sides of the surface of the bidirectional screw rod 701, and a movable wheel 704 is fixedly mounted on the front and rear sides of the fixed block 703, and an inclined block 705 is movably mounted on the opposite side of the two movable wheels 704, and a baffle 706 is fixedly mounted on the opposite side of the two inclined blocks 705, and a clamping block 707 is fixedly mounted on the opposite side of the two baffles 706, and two springs 708 are fixedly mounted on the opposite side of the two baffles 706, and the side of the spring 708 close to the mounting plate 6 is fixedly connected to the mounting plate 6. A limit block 709 is fixedly mounted on the bottom of the fixed block 703, and a limit shell 710 is arranged on the surface of the limit block 709, and the limit shell 710 is fixedly connected to the mounting plate 6 on the side close to the mounting plate 6. Sliding blocks 711 are fixedly installed on both sides of the baffle 706 , and a sliding rod 712 is slidably installed in the inner cavity of the sliding block 711 . The sliding rod 712 is fixedly connected to the mounting plate 6 on one side close to the mounting plate 6 .

[0042] During the implementation process, the lubricating oil tank 8 is placed on the top of the mounting plate 6, and the limit plate 9 enters the interior of the mounting plate 6 through the top of the mounting plate 6. By rotating the rotating disk 702, the rotating disk 702 will drive the bidirectional screw rod 701 to rotate when it rotates, and the bidirectional screw rod 701 will drive the two fixed blocks 703 to approach each other when it rotates. When the fixed block 703 moves, it will push the inclined block 705 to move through the movable wheel 704. When the inclined block 705 moves, it will drive the baffle plate 706 to move. When the baffle plate 706 moves, it will drive the card block 707 to move, and the card block 707 will be moved. When the baffle plate 706 moves, it will squeeze the spring 708. When it needs to be disassembled, the rotating disk 702 is rotated in the opposite direction to move the movable wheel 704 to its original position. The spring 708 rebounds and drives the inclined block 705, the baffle plate 706 and the card block 707 to reset, so that the card block 707 is moved out of the limit plate 9. The limit plate 9 can be disassembled. The lubricating oil tank 8 is installed on the limit plate 9 and will be installed and disassembled with the limit plate 9. It is more convenient to install and disassemble the lubricating oil tank 8 when it needs to be installed and disassembled.

[0043] Example 2

[0044] The lubrication assembly 13 includes an oil inlet pipe 1301, which is connected to the right side of the connecting sleeve 12. The right side of the oil inlet pipe 1301 is connected to a micro oil pump 1302. The side of the micro oil pump 1302 close to the crankcase 1 is fixedly connected to the crankcase 1. The right side of the micro oil pump 1302 is connected to six oil outlet pipes 1303. The bottom of the oil outlet pipe 1303 is connected to a connecting pipe 1304. The opposite sides of the two connecting pipes 1304 are connected to nozzles 1305.

[0045] During the implementation process, by starting the micro oil pump 1302, the lubricating oil inside the lubricating oil tank 8 is transported to the inside of the connecting pipe 1304 through the oil inlet pipe 1301, the micro oil pump 1302 and the oil outlet pipe 1303, and the lubricating oil inside the connecting pipe 1304 is sprayed to the inside of the slide hole 2 through the nozzle 1305. The automatic addition of lubricating oil can effectively reduce the friction of the plunger body 4 in the slide hole 2, thereby extending the service life of the components and reducing wear. The automatic addition of lubricating oil can ensure the stable operation of the plunger body 4 in the slide hole 2, and improve the output stability and reliability of the pump.

[0046] When in use, the lubricating oil tank 8 is placed on the top of the mounting plate 6, and the limiting plate 9 enters the interior of the mounting plate 6 through the top of the mounting plate 6, and the rotating disk 702 is rotated. When the rotating disk 702 rotates, the bidirectional screw rod 701 is driven to rotate, and when the bidirectional screw rod 701 rotates, it drives the two fixed blocks 703 to approach each other. When the fixed block 703 moves, it pushes the inclined block 705 to move through the movable wheel 704, and when the inclined block 705 moves, it drives the baffle 706 to move, and when the baffle 706 moves, it drives the card block 707 to move, and moves the card block 707 to the groove on the limiting plate 9, so that the limiting plate 9 is fixed and installed, and the baffle 706 also squeezes the spring 708 when moving. When it needs to be disassembled, the rotating disk 702 is rotated in the opposite direction to move the movable wheel 704 to its original position, and the spring 708 rebounds to drive the inclined block 705, the baffle 706 and the card block 707 to reset, so that the card block 707 is moved out The limit plate 9 can be removed inside the limit plate 9. The lubricating oil tank 8 is installed on the limit plate 9 and will be installed and removed along with the limit plate 9. It is more convenient to install and remove the lubricating oil tank 8 when it needs to be installed and removed. The oil inlet pipe 1301 is threadedly connected to the connecting shell 11 through the connecting sleeve 12, which makes it more convenient to remove the oil inlet pipe 1301 from the connecting shell 11. By starting the micro oil pump 1302, the lubricating oil inside the lubricating oil tank 8 is transported to the inside of the connecting pipe 1304 through the oil inlet pipe 1301, the micro oil pump 1302 and the oil outlet pipe 1303. The lubricating oil inside the connecting pipe 1304 is sprayed to the inside of the slideway hole 2 through the nozzle 1305. Automatic addition of lubricating oil can effectively reduce the friction of the plunger body 4 in the slideway hole 2, thereby extending the service life of the components and reducing wear. Automatic addition of lubricating oil can ensure the stable operation of the plunger body 4 in the slideway hole 2 and improve the output stability and reliability of the pump.

[0047] The above embodiments are only used to illustrate the present invention and are not intended to limit the technical solutions described in the present invention. Although the present invention has been described in detail with reference to the above embodiments, the present invention is not limited to the above specific implementation methods. Therefore, any modification or equivalent replacement of the present invention; and all technical solutions and improvements thereof that do not depart from the spirit and scope of the invention are included in the scope of the claims of the present invention.

Claims

1. A self-lubricating device for a slideway hole of a high-pressure pump in a coal mine, comprising a crankcase (1), characterized in that: The inner cavity of the crankcase (1) is provided with three slideway holes (2), the left side of the inner cavity of the crankcase (1) is provided with three plunger connecting rods (3), the right side of the plunger connecting rods (3) is provided with a plunger body (4), the right side of the crankcase (1) is provided with a pump head (5), the left side of the top of the crankcase (1) is fixedly mounted with a mounting plate (6), the left side of the inner cavity of the mounting plate (6) is movably mounted with a mounting assembly (7), the top of the mounting plate (6) is detachably mounted with a lubricating oil tank (8), the four corners of the bottom of the lubricating oil tank (8) are fixedly mounted with limit plates (9), the front side and the rear side of the top of the mounting plate (6) are fixedly mounted with side plates (10), the right side of the lubricating oil tank (8) is fixedly mounted with a connecting shell (11), the right side of the connecting shell (11) is threadedly connected with a connecting sleeve (12), and the right side of the connecting sleeve (12) is connected with a lubricating assembly (13).

2. The self-lubricating device for the slideway hole of a coal mine high-pressure pump according to claim 1, characterized in that: The mounting assembly (7) comprises a bidirectional screw (701), wherein the bidirectional screw (701) is movably mounted on the left side of the inner cavity of the mounting plate (6), a rotating disk (702) is fixedly mounted on the left side of the bidirectional screw (701), both sides of the surface of the bidirectional screw (701) are threadedly connected with fixed blocks (703), the front side and the rear side of the fixed block (703) are fixedly mounted with movable wheels (704), the opposite sides of the two movable wheels (704) are movably mounted with inclined blocks (705), the opposite sides of the two inclined blocks (705) are fixedly mounted with baffles (706), the opposite sides of the two baffles (706) are fixedly mounted with clamping blocks (707), and the opposite sides of the two baffles (706) are fixedly mounted with two springs (708), and the side of the spring (708) close to the mounting plate (6) is fixedly connected to the mounting plate (6).

3. The self-lubricating device for the slideway hole of a coal mine high-pressure pump according to claim 2, characterized in that: A limiting block (709) is fixedly mounted on the bottom of the fixing block (703), a limiting shell (710) is provided on the surface of the limiting block (709), and a side of the limiting shell (710) close to the mounting plate (6) is fixedly connected to the mounting plate (6).

4. The self-lubricating device for slideway holes of a high-pressure pump in a coal mine according to claim 2, characterized in that: Sliding blocks (711) are fixedly mounted on both sides of the baffle (706), a sliding rod (712) is slidably mounted in the inner cavity of the sliding block (711), and the sliding rod (712) is fixedly connected to the mounting plate (6) on a side close to the mounting plate (6).

5. The self-lubricating device for slideway holes of a coal mine high-pressure pump according to claim 1, characterized in that: The lubrication assembly (13) comprises an oil inlet pipe (1301), the oil inlet pipe (1301) being connected to the right side of the connecting sleeve (12), the right side of the oil inlet pipe (1301) being connected to a micro oil pump (1302), the side of the micro oil pump (1302) close to the crankcase (1) being fixedly connected to the crankcase (1), the right side of the micro oil pump (1302) being connected to six oil outlet pipes (1303), the bottom of the oil outlet pipe (1303) being connected to a connecting pipe (1304), and the two connecting pipes (1304) being connected to nozzles (1305) on opposite sides thereof.

6. The self-lubricating device for slideway holes of a coal mine high-pressure pump according to claim 1, characterized in that: Two positioning plates (14) are fixedly mounted on the front and rear sides of the mounting plate (6); the side of the positioning plate (14) close to the crankcase (1) is fixedly connected to the crankcase (1).

7. The self-lubricating device for slideway holes of a high-pressure pump in a coal mine according to claim 1, characterized in that: A fixing ring (15) is sleeved on the surface of the connection shell (11), and a side of the fixing ring (15) close to the lubricating oil tank (8) is fixedly connected to the lubricating oil tank (8).

8. The self-lubricating device for slideway holes of a coal mine high-pressure pump according to claim 1, characterized in that: The surface of the connecting sleeve (12) is provided with a screw thread (16), and the inner cavity of the connecting shell (11) is provided with a screw thread groove (17).

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