Rotary connecting structure of liquefied gas spray gun

Abstract

The utility model belongs to the technical field of liquefied gas spray guns, and relates to a rotary connection structure of a liquefied gas spray gun, which comprises a first pipe fitting connected with a pipe joint and a second pipe fitting connected with a metal pipe, the outer wall of the first connecting end is in contact connection with the inner wall of the second connecting end to form a sealing surface, circumferential limiting grooves are formed in the same axial positions of the outer wall of the first connecting end and the inner wall of the second connecting end, and a plurality of balls for axially limiting the first connecting end and the second connecting end are arranged in the limiting grooves. The rotary connection structure of the liquefied gas spray gun has the advantages of being good in sealing performance, flexible in rotation and long in service life.

Description

Technical Field

[0001] The utility model belongs to the technical field of liquefied gas spray guns and relates to a rotary connection structure of a liquefied gas spray gun. Background Art

[0002] The liquefied gas flamethrower is a heating tool that uses liquefied gas as fuel. If used correctly, it can reach a high temperature of 1300°. It has the advantages of low cost, safety, convenience, no pollution, and stable performance. It is widely used in occasions that require flame or heating.

[0003] Chinese utility model patent CN 219473642 U (announcement date 2023.08.04) discloses a handle of a liquefied gas spray gun, the handle comprising a handle shell and a metal connecting pipe inserted in the handle shell, the handle also comprising: a joint, which comprises a rotating part inserted in the handle shell and a connecting part for connecting a liquefied gas supply hose, the rotating part extends along a first axis, the connecting part extends along a second axis, and the first axis and the second axis form an angle greater than 0 and less than 180 degrees; an outer connecting sleeve, which is arranged in the handle shell and has opposite distal and proximal ends, the proximal end of the metal connecting pipe is fixedly connected to the distal end of the outer connecting sleeve, and the rotating part can be rotatably connected to the proximal end of the outer connecting sleeve around the first axis; wherein the tube cavity of the metal connecting pipe and the inner cavity of the joint are connected to each other. In addition, a hollow shaft is arranged in the outer connecting sleeve, one end of the hollow shaft is inserted in the proximal end of the metal connecting pipe and is sealed by a sealing ring, and the other end of the hollow shaft can be relatively rotatably inserted in the rotating part and is sealed by a sealing ring.

[0004] The rotating connection part of the above-mentioned patent is sealed by a sealing ring, which not only has the risk of leakage due to deformation and aging, but also the sealing ring will hinder the rotation of the rotating part. Utility Model Content

[0005] The utility model aims at the deficiencies of the prior art and provides a rotary connection structure of a liquefied gas spray gun, which has the advantages of good sealing performance, flexible rotation and long service life.

[0006] In order to solve the above technical problems, the purpose of the utility model is achieved through the following technical solutions:

[0007] A rotary connection structure for a liquefied gas spray gun comprises a first pipe fitting connected to a pipe joint and a second pipe fitting connected to a metal pipe, wherein a first connection end of the first pipe fitting is rotatably inserted into a second connection end of the second pipe fitting, an outer wall of the first connection end is in contact with and connected to an inner wall of the second connection end to form a sealing surface, an outer wall of the first connection end and an inner wall of the second connection end are provided with circumferential limiting grooves at the same axial position, and a plurality of balls for axially limiting the first connection end and the second connection end are provided in the limiting grooves.

[0008] In the above-mentioned rotary connection structure of a liquefied gas spray gun, the limiting grooves on the outer wall of the first connection end and the inner wall of the second connection end have the same groove depth. Further, the groove depth of the limiting grooves on the first connection end and the second connection end is half of the groove width, and the limiting grooves on the first connection end and the second connection end are assembled to form a combined groove with the same groove depth and width and a square cross-section.

[0009] In the above-mentioned rotary connection structure of a liquefied gas spray gun, the combined groove depth of the limiting groove is the same as the diameter of the ball; the combined groove depth refers to the groove depth of the combined groove formed after the first connecting end and the second connecting end are assembled.

[0010] In the above-mentioned rotating connection structure of a liquefied gas spray gun, a mounting hole connected to the limiting groove is radially arranged on the second pipe fitting, the hole diameter of the mounting hole is larger than the diameter of the ball, and the ball can enter the limiting groove along the mounting hole; the mounting hole can be either a cylindrical hole or a conical hole that is larger at the top and smaller at the bottom.

[0011] In the above-mentioned rotary connection structure of a liquefied gas spray gun, a plug is detachably connected in the mounting hole, and the plug adopts a conventional structure in the art, such as an elastic member with an interference fit, or a threaded bolt.

[0012] In the above-mentioned rotating connection structure of a liquefied gas spray gun, the limiting groove divides the outer wall of the first connecting end and the inner wall of the second connecting end into a proximal metal pipe end and a proximal pipe joint end, and the sealing surface is arranged at the proximal metal pipe end; the proximal pipe joint end does not need to be provided with a sealing surface.

[0013] In the above-mentioned rotating connection structure of a liquefied gas spray gun, the outer wall of the first connection end and the inner wall of the second connection end are heat treated and then finely ground to form a sealing surface; the fine grinding adopts conventional abrasives or grinding compositions used for fine grinding of sealing surfaces in the art, and the fine grinding method adopts manual grinding or grinding with a grinder; preferably, the outer wall of the first connection end and the inner wall of the second connection end can be finely ground synchronously.

[0014] In the above-mentioned rotary connection structure of a liquefied gas spray gun, the pipe joint is detachably connected to the first pipe member, and the axis of the pipe joint forms an angle with the axis of the first pipe member.

[0015] Alternatively, in the above-mentioned rotary connection structure of a liquefied gas spray gun, the pipe joint and the first pipe member are integrally formed, and the axis of the pipe joint is coaxially arranged with the axis of the first pipe member.

[0016] Compared with the prior art, the utility model has the following beneficial effects:

[0017] The utility model provides a rotary connection structure of a liquefied gas spray gun, which no longer uses a conventional sealing ring sealing structure, but uses a matching sealing surface to be set on the outer wall of the first connection end and the inner wall of the second connection end for sealing, thereby having a better sealing effect and not causing leakage due to deformation or aging. At the same time, the utility model uses a limit groove and a plurality of balls to form an axial limit structure, which can ensure more flexible rotation between the first pipe fitting and the second pipe fitting while limiting the axial position. Therefore, the utility model has the advantages of good sealing, flexible rotation and long service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a three-dimensional diagram of embodiment 1 of the utility model;

[0019] Figure 2 is an axial cross-sectional view of Embodiment 1 of the present utility model;

[0020] Figure 3 It is a stereogram of Embodiment 2 of the present utility model;

[0021] Figure 4 It is an axial cross-sectional view of Embodiment 2 of the present utility model;

[0022] Figure numerals: 1, pipe joint; 2, first pipe fitting; 3, second pipe fitting; 4, first connecting end; 5, second connecting end; 6, limiting groove; 7, ball bearing; 8, mounting hole. DETAILED DESCRIPTION

[0023] The present invention will be further described below with reference to the accompanying drawings. Figure 1-4 :

[0024] Example 1

[0025] Compare with Figure 1 and attached Figure 2 A rotary connection structure of a liquefied gas spray gun comprises a first pipe fitting 2 connected to a pipe joint 1 and a second pipe fitting 3 connected to a metal pipe, a first connection end 4 of the first pipe fitting 2 being rotatably inserted into a second connection end 5 of the second pipe fitting 3, an outer wall of the first connection end 4 being in contact with an inner wall of the second connection end 5 and forming a sealing surface, an outer wall of the first connection end 4 and an inner wall of the second connection end 5 being provided with a circumferential limiting groove 6 at the same axial position, a plurality of balls 7 for axially limiting the first connection end 4 and the second connection end 5 being provided in the limiting groove 6.

[0026] When in use, the pipe joint 1 is connected to the hose of the air supply device, and the liquefied gas is transported through the pipe joint 1, the first pipe fitting 2, the second pipe fitting 3 and the inner cavity of the metal pipe in sequence; the first connecting end 4 of the first pipe fitting 2 and the second connecting end 5 of the second pipe fitting 3 can rotate relatively, thereby reducing the restriction of the hose on the use angle of the spray gun and reducing the torsion of the hose; during the transportation process, the outer wall of the first connecting end 4 and the inner wall of the second connecting end 5 form a sealing surface, which can avoid leakage of liquefied gas, and the use of a surface sealing method can also enhance the sealing effect; after assembly, the ball 7 is rolled and arranged in a combined limiting groove formed by the limiting groove 6 on the outer wall of the first connecting end 4 and the limiting groove 6 on the inner wall of the second connecting end 5, the outermost end of the ball 7 exceeds the surface where the inner wall of the second connecting end 5 is located, and the innermost end exceeds the surface where the outer wall of the first connecting end 4 is located, so an axial limiting structure can be formed to prevent the first connecting end 4 and the second connecting end 5 from being separated, and the rolling of the ball 7 can also make the first connecting end 4 and the second connecting end 5 rotate flexibly.

[0027] Compare with Figure 2 In this embodiment, the limiting grooves 6 on the outer wall of the first connection end 4 and the inner wall of the second connection end 5 have the same groove depth. Further, the groove depth of the limiting grooves 6 on the first connection end 4 and the second connection end 5 is half of the groove width, and the limiting grooves 6 on the first connection end 4 and the second connection end 5 are assembled to form a combined groove with the same groove depth and width and a square cross section.

[0028] In order to better match with the ball 7 , the combined groove depth of the limiting groove 6 is the same as the diameter of the ball 7 .

[0029] The installation structure of the ball 7 in this embodiment is: a mounting hole 8 connected to the limiting groove 6 is radially arranged on the second pipe 3, the hole diameter of the mounting hole 8 is larger than the diameter of the ball 7, and the ball 7 can enter the limiting groove 6 along the mounting hole 8; the mounting hole 8 can be either a cylindrical hole or a conical hole that is larger at the top and smaller at the bottom.

[0030] A plug (not shown in the drawings) is detachably connected to the mounting hole 8 . After all the balls 7 are installed in the limiting grooves 6 , the plug can be installed to prevent the balls 7 from falling out of the mounting hole 8 .

[0031] For the convenience of processing, the limiting groove 6 divides the outer wall of the first connecting end 4 and the inner wall of the second connecting end 5 into a metal pipe end and a pipe joint end. The sealing surface is arranged at the metal pipe end; the pipe joint end does not need to be provided with a sealing surface.

[0032] In this embodiment, the sealing surface is processed in the following manner: the outer wall of the first connection end 4 and the inner wall of the second connection end 5 are heat treated and then finely ground to form a sealing surface. In this embodiment, the outer wall of the first connection end 4 and the inner wall of the second connection end 5 are first heat treated to increase the hardness of the outer wall and the inner wall of the second connection end 5 to improve the wear resistance, and then fine grinding is performed to reduce the surface roughness to form a sealing surface; the fine grinding adopts conventional abrasives or abrasive compositions used for fine grinding of sealing surfaces in the art, and the fine grinding method adopts manual grinding or grinding with a grinder; preferably, the outer wall of the first connection end 4 and the inner wall of the second connection end 5 can be finely ground synchronously.

[0033] Compare with Figure 2 The pipe joint 1 is detachably connected to the first pipe fitting 2, and the axis of the pipe joint 1 forms an angle with the axis of the first pipe fitting 2.

[0034] Example 2

[0035] Compare with Figure 3 and attached Figure 4 The structure in Example 2 is substantially the same as that in Example 1, except that the connection structure between the pipe joint 1 and the first pipe fitting 2 is as follows: the pipe joint 1 and the first pipe fitting 2 are integrally formed, and the axis of the pipe joint 1 is coaxially arranged with the axis of the first pipe fitting 2.

[0036] Through Example 1 and Example 2, it is explained that the connection structure of the utility model can be adapted to liquefied gas spray guns of various specifications.

[0037] The above embodiments are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A rotary connection structure for a liquefied gas spray gun, comprising a first pipe member (2) connected to a pipe joint (1) and a second pipe member (3) connected to a metal pipe, wherein a first connection end (4) of the first pipe member (2) is rotatably inserted into a second connection end (5) of the second pipe member (3), characterized in that: The outer wall of the first connecting end (4) is in contact with the inner wall of the second connecting end (5) to form a sealing surface. The outer wall of the first connecting end (4) and the inner wall of the second connecting end (5) are respectively provided with circumferential limiting grooves (6) at the same axial position. A plurality of balls (7) for axially limiting the first connecting end (4) and the second connecting end (5) are provided in the limiting grooves (6).

2. The rotary connection structure of a liquefied gas spray gun according to claim 1, characterized in that: The limiting groove (6) on the outer wall of the first connecting end (4) and the inner wall of the second connecting end (5) have the same groove depth.

3. The rotary connection structure of a liquefied gas spray gun according to claim 1, characterized in that: The combined groove depth of the limiting groove (6) is the same as the diameter of the ball (7).

4. The rotary connection structure of a liquefied gas spray gun according to claim 1, characterized in that: The second pipe member (3) is provided with a mounting hole (8) in radial direction and connected with the limiting groove (6); the diameter of the mounting hole (8) is larger than the diameter of the ball (7); and the ball (7) can enter the limiting groove (6) along the mounting hole (8).

5. The rotary connection structure of a liquefied gas spray gun according to claim 4, characterized in that: The mounting hole (8) is detachably connected with a plug.

6. The rotary connection structure of a liquefied gas spray gun according to claim 1, characterized in that: The limiting groove (6) divides the outer wall of the first connecting end (4) and the inner wall of the second connecting end (5) into an end near the metal pipe and an end near the pipe joint, and the sealing surface is arranged at the end near the metal pipe.

7. The rotary connection structure of a liquefied gas spray gun according to claim 1, characterized in that: The outer wall of the first connecting end (4) and the inner wall of the second connecting end (5) are heat treated and then finely ground to form a sealing surface.

8. The rotary connection structure of a liquefied gas spray gun according to claim 1, characterized in that: The pipe joint (1) is detachably connected to the first pipe member (2), and the axis of the pipe joint (1) forms an angle with the axis of the first pipe member (2).

9. The rotary connection structure of a liquefied gas spray gun according to claim 1, characterized in that: The pipe joint (1) and the first pipe member (2) are integrally formed, and the axis of the pipe joint (1) is coaxially arranged with the axis of the first pipe member (2).

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