Piston gas circuit sealing structure and air cylinder

Abstract

The utility model discloses a piston gas circuit sealing structure and an air cylinder, a piston is provided with a connecting rod (1), a piston seat (2) and a gland (3), the piston seat (2) is provided with a first boss (21), the gland (3) is provided with a first groove (31), and the first groove (31) is buckled on the first boss (21); a through hole (32) is formed in the groove bottom of the first groove (31), and a first threaded hole (22) is formed in the first boss (21); a first screw penetrates through the through hole (32) and then is connected with the first threaded hole (22); a first annular groove (211) is formed in the top of the first boss (21), and a second sealing ring (5) is placed in the first annular groove (211) and used for sealing the first annular groove (211) and the first groove (31). The first annular groove (211) in the top face of the piston seat (2) is in the state that the opening faces upwards when the piston is assembled, the second sealing ring (5) is placed in the first annular groove (211), and whether the second sealing ring (5) falls off or not and whether the position is accurate or not can be observed easily.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of air compressors, and particularly relates to a piston air path sealing structure and a cylinder. BACKGROUND

[0002] The cylinder in the air compressor has a piston and a cylinder sleeve; when the piston is assembled, usually, the connecting rod is in a vertical state on the work station, the piston seat is located on the work station above the connecting rod, and the gland is located on the work station above the piston seat; the existing sealing ring is arranged in a downward groove on the gland, and the sealing ring is fixed in the groove on the bottom surface of the gland by using over-tight fitting, but there is still a high probability of misplacement or falling off. SUMMARY

[0003] The application discloses a piston air path sealing structure, a piston has a connecting rod, a piston seat arranged at one end of the connecting rod, and a gland detachably connected with the piston seat, a first sealing ring is arranged between the edges of the piston seat and the gland, and the piston seat is bowl-shaped, and the bowl-shaped opening faces the gland.

[0004] The piston seat is bowl-shaped, and the bowl-shaped opening faces the gland;

[0005] One side of the piston seat facing the gland is provided with a first boss, a first groove is arranged on the gland, and the first groove is buckled on the first boss;

[0006] A through hole is formed in the groove bottom of the first groove, and a first threaded hole is formed in the first boss;

[0007] A first screw is connected with the first threaded hole after penetrating through the through hole;

[0008] The top of the first boss is provided with a first annular groove, a second sealing ring is placed in the first annular groove, and the second sealing ring is used for sealing the top surface of the first annular groove and the groove bottom of the first groove.

[0009] Further, the first boss and the first groove are both two;

[0010] The bottom of the first threaded hole is in a closed state.

[0011] Further, a first air hole is arranged on the gland, a second air hole is arranged on the piston seat, and the centers of the first air hole and the second air hole are consistent;

[0012] One side of the gland away from the piston seat is provided with an elastic valve plate, one end of the elastic valve plate is fixed on the gland, and the other end cover is arranged on the first air hole.

[0013] Further, a second groove is formed in the side of the gland facing the piston seat along the edge of the first air hole;

[0014] Along the edge of the second air hole, a second boss is provided on the piston seat on the side facing the gland;

[0015] A third sealing ring is provided between the second boss and the second groove.

[0016] Furthermore, the top of the second boss is provided with a second annular groove, and the third sealing ring is placed in the second annular groove.

[0017] Furthermore, the second and third sealing rings are made of silicone rubber.

[0018] On the other hand, this application proposes a cylinder, including a cylinder liner and a piston having the piston air passage sealing structure of any of the above-mentioned technical solutions.

[0019] The above-mentioned technical solution of this application has at least the following beneficial technical effects:

[0020] In this application, the first annular groove on the top surface of the piston seat is in an upward-facing state during piston assembly. The second sealing ring is placed in the first annular groove, making it easy to observe whether it has fallen off and whether its position is accurate. In addition, the second sealing ring can be further ensured to be in the correct position in the first annular groove by overtight fitting. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application or in the conventional technology, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a front cross-sectional view of an air compressor according to one embodiment of this application.

[0023] Figure 2 This is a partial front cross-sectional view of a piston in one embodiment of this application - A.

[0024] Figure 3 This is a perspective view of the cover in one embodiment of this application.

[0025] Figure 4 This is a perspective view of the piston seat and connecting rod in one embodiment of this application.

[0026] Figure 5 This is a partial cross-sectional view of the piston in one embodiment of this application.

[0027] in, Figures 1 to 5 The correspondence between the reference numerals and component names in the attached drawings is as follows:

[0028] 1. Connecting rod;

[0029] 2. Piston seat; 21. First boss; 211. First annular groove; 212. First limiting groove; 22. First threaded hole; 23. Second vent; 24. Second boss; 241. Second annular groove;

[0030] 3. Pressure cap; 31. First groove; 312. First limiting boss; 32. Through hole; 33. First vent; 34. Second groove; 35. Elastic valve plate;

[0031] 4. First sealing ring; 5. Second sealing ring; 6. Third sealing ring; 7. Cylinder liner. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the various embodiments of this application will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details are presented in the various embodiments of this application to facilitate a better understanding of the application. However, the technical solutions claimed in this application can be implemented even without these technical details and various variations and modifications based on the following embodiments. The division of the various embodiments below is for ease of description and should not constitute any limitation on the specific implementation of this application. The various embodiments can be combined with and referenced by each other without contradiction.

[0033] Currently, during piston assembly, connecting rod 1 is in a vertical position at the work station, piston seat 2 is located above connecting rod 1 at the work station, and pressure cap 3 is located above piston seat 2 at the work station; the existing sealing ring is located in the downward-facing groove on pressure cap 3, and the sealing ring is fixed in the groove on the bottom surface of pressure cap 3 by using an overtight fit, but there is still a high probability of misalignment or falling off.

[0034] To solve the above problems, such as Figure 1 and 2 As shown, one embodiment of this application discloses a piston gas passage sealing structure applied to a piston. The piston has a connecting rod 1, a piston seat 2, and a pressure cap 3. A first sealing ring 4 is sandwiched between the edges of the piston seat 2 and the pressure cap 3. The connecting rod 1 is fixedly connected to one side of the piston seat 2, and the pressure cap 3 is detachably connected to the other side of the piston seat 2. The first sealing ring 4 is mainly used for dynamic sealing between the piston and the matching cylinder liner 7, and also seals the edges of the piston seat 2 and the pressure cap 3. The piston gas passage sealing structure specifically includes:

[0035] The piston seat 2 is bowl-shaped, with the bowl-shaped opening facing the pressure cap 3; the pressure cap 3 can be one end face sealed to the top surface of the bowl-shaped opening through the first sealing ring 4, or the outer peripheral surface of the pressure cap 3 can be sealed to the inner surface of the bowl-shaped opening through the first sealing ring 4.

[0036] The piston seat 2 has a first boss 21 on the side facing the pressure cap 3, the pressure cap 3 has a first groove 31, the bottom of the first groove 31 has a through hole 32, and the first boss 21 has a first threaded hole 22.

[0037] After the first groove 31 is engaged with the first boss 21, the two do not directly contact each other; the first screw passes through the through hole 32 and connects with the first threaded hole 22, thereby fixing the cover 3 and the connecting rod 1 relative to each other, and pressing the first sealing ring 4 to seal the edge of the cover 3 and the piston seat 2.

[0038] The top of the first protrusion 21 is provided with a first annular groove 211, and a second sealing ring 5 is placed in the first annular groove 211. The second sealing ring 5 seals the top surface of the first annular groove 211 and the bottom of the first groove 31, thereby ensuring that the gas on the side of the pressure cap 3 will not pass through the through hole 32 and the first threaded hole 22, and the gas will not flow through the gap between the pressure cap 3 and the piston seat 2, thus ensuring the airtightness of the piston. Furthermore, since the first annular groove 211 on the top surface of the piston seat 2 of this application is in an open-facing state during piston assembly, the second sealing ring 5 is placed in the first annular groove 211, making it easy to observe whether it has fallen off and whether its position is accurate. In addition, the second sealing ring 5 can be further ensured to be in the correct position in the first annular groove 211 by using an overtight fit.

[0039] In one embodiment, there are two first bosses 21 and two first grooves 31, each with identical through holes, threaded holes, screws, etc. Preferably, the first bosses 21 and the first threaded holes 22 are located at the connection between the connecting rod 1 and the piston seat 2. This location can utilize a larger solid volume, allowing the first threaded holes 22 to pass through the piston seat 2 into the connecting rod 1. The bottom of the first threaded holes 22 is closed, preventing gas from flowing through the first threaded holes 22 when they are in a through-hole state.

[0040] In one embodiment, such as Figure 3 and Figure 4 As shown, on the pressure cap 3, along the edge of the through hole 32, a first limiting boss 312 extends from the bottom of the first groove 31 toward the piston seat 2. The first limiting boss 312 is annular. On the piston seat 2, along the center of the first threaded hole 22, a first limiting groove 212 is provided on the top of the first boss 21.

[0041] The first limiting boss 312 can be pre-embedded in the first limiting groove 212. The first limiting boss 312 and the first limiting groove 212 do not contact each other, which prevents the second sealing ring 5 from being misaligned and falling off. In an optional embodiment, the first limiting top surface of the first limiting boss 312 abuts against the second limiting top surface of the first limiting groove 212 to axially limit the pressure cap 3; the first limiting outer peripheral surface of the first limiting boss 312 abuts against the second limiting outer peripheral surface of the first limiting groove 212 to radially limit the pressure cap 3.

[0042] In one embodiment, the pressure cap 3 is provided with a first vent 33, and the piston seat 2 is provided with a second vent 23, with the first vent 33 and the second vent 23 aligned at their centers. An elastic valve plate 35 is provided on the side of the pressure cap 3 facing away from the piston seat 2, with one end fixed to the pressure cap 3 and the other end covering the first vent 33. The elastic valve plate 35 isolates or allows the gas on the upper side of the pressure cap 3 to flow with the gas on the lower side of the piston seat 2 by closing or opening the first vent 33.

[0043] Preferably, a second groove 34 is provided on the cap 3 along the edge of the first air hole 33 on the side of the cap 3 facing the piston seat 2; and a second boss 24 is provided on the piston seat 2 along the edge of the second air hole 23 on the side of the piston seat 2 facing the cap 3.

[0044] The second protrusion 24 is embedded in the second groove 34, and a third sealing ring 6 is provided between them. Thus, through the third sealing ring 6, the second sealing ring 5 and the first sealing ring 4, the gap between the pressure cap 3 and the piston seat 2 is kept in a sealed and isolated state from the outside world. This prevents aluminum shavings generated when tightening the first screw or when the pressure cap 3 collides with the piston seat 2 during piston assembly from entering the cylinder through the two air holes. At the same time, it also ensures that the gap between the pressure cap 3 and the piston seat 2 has a stable internal pressure, and prevents the continuous change of air pressure caused by piston movement from affecting the stability of the connection between the pressure cap 3 and the piston seat 2.

[0045] Preferably, the top of the second boss 24 on the piston seat 2 is provided with a second annular groove 241, and a third sealing ring 6 is placed in the second annular groove 241; similarly, the second annular groove 241 faces upward during assembly, and the third sealing ring 6 is not easy to fall off.

[0046] In one embodiment, the second sealing ring 5 and the third sealing ring 6 of this application are made of silicone rubber. Traditional sealing rings are mostly made of nitrile rubber, which has the advantages of being oil-resistant and wear-resistant, but its high and low temperature resistance is poor, making it suitable for sliding seals at low temperatures. The second sealing ring 5 and the third sealing ring 6 of this application, or existing sealing rings, are static seals. When the piston compresses air, the compressed air generates a high temperature of 136°C (theoretical value), making nitrile rubber unsuitable. The silicone rubber second sealing ring 5 and the third sealing ring 6 of this application are more suitable.

[0047] On the other hand, this application proposes a cylinder, including a cylinder liner 7 and a piston having the piston air passage sealing structure of any of the above technical solutions, thus having all the advantages and beneficial effects of the piston air passage sealing structure of any of the above technical solutions, which will not be repeated here.

[0048] Furthermore, this application proposes an air compressor having the cylinder described in the above-mentioned technical solution. The air compressor also includes an electric motor, which drives the cylinder to compress air.

[0049] In the description of this invention, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this invention, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0050] It should be understood that the specific embodiments described above are merely illustrative or explanatory of the principles of this application and do not constitute a limitation thereof. Therefore, any modifications, equivalent substitutions, improvements, etc., made without departing from the spirit and scope of this application should be included within the protection scope of this application. Furthermore, the appended claims are intended to cover all variations and modifications falling within the scope and boundaries of the appended claims, or equivalent forms of such scope and boundaries.

Claims

1. A piston gas passage sealing structure, wherein the piston has a connecting rod (1), a piston seat (2) disposed at one end of the connecting rod (1), and a pressure cap (3) detachably connected to the piston seat (2), wherein a first sealing ring (4) is sandwiched between the edges of the piston seat (2) and the pressure cap (3), characterized in that, include: The piston seat (2) is bowl-shaped, with the bowl-shaped opening facing the pressure cap (3); The piston seat (2) has a first protrusion (21) on the side facing the pressure cap (3), and the pressure cap (3) has a first groove (31) which is engaged with the first protrusion (21). The bottom of the first groove (31) is provided with a through hole (32), and the first boss (21) is provided with a first threaded hole (22); The first screw passes through the through hole (32) and connects to the first threaded hole (22); The top of the first boss (21) is provided with a first annular groove (211), and a second sealing ring (5) is placed in the first annular groove (211). The second sealing ring (5) is used to seal the top surface of the first annular groove (211) and the bottom of the first groove (31).

2. The piston gas passage sealing structure according to claim 1, characterized in that, There are two of the first boss (21) and the first groove (31); The bottom of the first threaded hole (22) is closed.

3. The piston gas passage sealing structure according to claim 1, characterized in that, The pressure cap (3) is provided with a first air hole (33), and the piston seat (2) is provided with a second air hole (23). The first air hole (33) and the second air hole (23) are aligned at the center. An elastic valve plate (35) is provided on the side of the pressure cap (3) facing away from the piston seat (2). One end of the elastic valve plate (35) is fixed on the pressure cap (3), and the other end is covered on the first air hole (33).

4. The piston gas passage sealing structure according to claim 3, characterized in that, Along the edge of the first air hole (33), a second groove (34) is provided on the side of the pressure cap (3) facing the piston seat (2); Along the edge of the second air hole (23), a second boss (24) is provided on the piston seat (2) on the side facing the pressure cap (3); A third sealing ring (6) is provided between the second boss (24) and the second groove (34).

5. The piston gas passage sealing structure according to claim 4, characterized in that, The top of the second boss (24) is provided with a second annular groove (241), and the third sealing ring (6) is placed in the second annular groove (241).

6. The piston gas passage sealing structure according to claim 4, characterized in that, The second sealing ring (5) and the third sealing ring (6) are made of silicone rubber.

7. A cylinder, characterized in that, It includes a cylinder liner (7) and a piston having a piston air passage sealing structure as described in any one of claims 1-6.

Images