A piston with a composite fixed piston pin

Abstract

This utility model discloses a piston with a composite fixed piston pin, including a piston body, a receiving cavity formed within the piston body, two opposing piston pin seats formed on the sidewall of the receiving cavity, a receiving groove formed on each piston pin seat, the opening of the receiving groove located within the receiving cavity, and insertion ends formed at both ends of the piston pin that match the receiving groove, with at least a portion of the insertion ends located within the receiving groove; it also includes a fixing structure for fixing the piston pin. By changing the structure of the piston pin mounting hole, i.e., the cylindrical through hole, and eliminating the end of the hole formed on the outer surface of the piston body, the expansion degree of the guide piston ring towards the inner wall of the piston cylinder becomes more uniform when the guide piston ring expands, making the friction degree of the guide piston ring along the inner wall of the piston cylinder basically consistent, thus improving the life of the guide piston ring.

Description

Technical Field

[0001] This utility model relates to the field of piston technology, specifically to a piston suitable for air compressors, especially for oil-free piston electric air compressors, and having a composite fixed piston pin. Background Technology

[0002] In the existing structure of oil-free reciprocating electric air compressors, a cylindrical through-hole (i.e., piston pin hole) is often provided in the middle section of the piston. The cylindrical piston pin is inserted through this through-hole, and then a fixing screw is radially locked in. A guide piston ring is then wrapped around the middle section of the piston (guide piston ring groove). The guide piston ring undergoes reciprocating frictional motion with the piston's reciprocating motion. During this reciprocating frictional motion, the guide piston ring generates heat and expands. Because there is a certain gap between the guide piston ring and the piston pin at both ends, during expansion, the guide piston ring expands not only towards the piston cylinder wall but also towards the gap. This results in uneven expansion of the guide piston pin towards the piston cylinder wall, leading to severely inconsistent friction along the piston cylinder wall and thus affecting the service life of the guide piston ring. Utility Model Content

[0003] To solve the above-mentioned technical problems, this utility model provides a piston with a composite fixed piston pin, including a piston body, a receiving cavity formed within the piston body, two opposing piston pin seats formed on the sidewall of the receiving cavity, a receiving groove formed on each piston pin seat, the opening of the receiving groove being located within the receiving cavity, and insertion ends formed at both ends of the piston pin that match the receiving groove, with at least a portion of the insertion ends located within the receiving groove; it also includes a fixing structure for fixing the piston pin. By setting the opening of the receiving groove within the receiving cavity, that is, by changing the structure of the piston pin mounting hole, i.e., the cylindrical through hole, the end of the hole is no longer formed on the outer surface of the piston body (within the guide piston ring groove), and when the guide piston ring expands, the degree of expansion pointing towards the inner wall of the piston cylinder becomes more uniform, making the friction of the guide piston ring along the inner wall of the piston cylinder basically consistent, thus improving the life of the guide piston ring and also improving the sealing performance of the guide piston ring.

[0004] In one embodiment, the receiving groove includes at least three planar sidewalls.

[0005] Preferably, the accommodating groove has a U-shaped structure.

[0006] In another embodiment, the receiving groove includes at least one arc-shaped sidewall.

[0007] Preferably, the accommodating groove has a U-shaped structure.

[0008] More preferably, the insertion end is fitted into the receiving groove.

[0009] By defining the receiving groove of the above structure, it is convenient to install the piston pin and to match the insertion end with the receiving groove as much as possible.

[0010] Furthermore, the receiving groove includes at least one arc-shaped sidewall. Preferably, the receiving groove has a U-shaped structure. By setting the arc-shaped structure, the arc surface is connected to the plane, which can avoid the risk of stress concentration caused by the transition (turn) of the plane structure.

[0011] Furthermore, the fixing structure includes a stop member that fits against the insertion end and has a through hole, and a fixing member that fixes the stop member.

[0012] Furthermore, the fixing member is a fixing body with external threads and a through hole, and the side wall of the accommodating cavity forms an internal thread that is adapted to the external threads. After the fixing body is screwed into the internal threads, it fits against the stop member.

[0013] By having the stop and the insertion end fit together, and the fixing body and the stop fit together, the existing structure of fixing the piston pin with fixing screws is changed. By fitting the surfaces together and fixing with threads, the small contact area of ​​the fixing screw in the prior art is avoided, thus avoiding the problem of piston pin failure caused by cracks in the fixing screw due to the small contact area.

[0014] Furthermore, the fixing body has a groove formed on it to accommodate the deformed structure of the piston body after it has been riveted. By setting the groove, after the fixing body is tightened, the piston end is riveted according to the position of the groove, and the riveted deformed structure is embedded in the groove, which can effectively prevent vibration from loosening it.

[0015] Preferably, the stop member has a stop block formed on it that can extend into the receiving groove and fit against the insertion end. This structure can prevent the stop member from rotating during vibration and maintain the stability of the piston pin. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the specific embodiments of this utility model, the drawings used in the specific embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the piston with a composite fixed piston pin after installation according to this utility model;

[0018] Figure 2 This is a schematic diagram of the piston body of this utility model;

[0019] Figure 3 This is a schematic diagram of the piston pin structure of this utility model;

[0020] Figure 4 This is a structural schematic diagram of the stop component of this utility model;

[0021] Figure 5 This is a structural schematic diagram of the fastener of this utility model;

[0022] The reference numerals in the figure are as follows: 1-accommodating cavity; 2-piston pin seat; 3-accommodating groove; 4-piston pin; 5-insertion end; 6-stop; 7-fixed body; 8-groove; 9-stop block. Detailed Implementation

[0023] The present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Other embodiments derived by those skilled in the art from the embodiments of the present invention without inventive effort are all within the scope of protection of the present invention.

[0024] In the description of this utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0025] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0026] Furthermore, the technical features involved in the different embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.

[0027] Example 1

[0028] This embodiment discloses a piston with a composite fixed piston pin, comprising a piston body, a receiving cavity 1 formed within the piston body, one end of a connecting rod assembly extending into the receiving cavity 1 and connected to a piston pin, and two opposing piston pin seats 2 formed on the side wall of the receiving cavity 1, preferably integrally formed with the piston body, each piston pin seat 2 having a receiving groove 3 formed thereon, the opening of the receiving groove 3 located within the receiving cavity 1, and two ends of the piston pin 4 forming insertion ends 5 that match the receiving groove 3, at least part of the insertion ends 5 located within the receiving groove 3. As for the method of inserting the insertion ends 5 into the receiving groove 3, based on the characteristic that the opening of the receiving groove 3 is located within the receiving cavity 1, the piston pin 4 is inserted into the receiving groove 3 through the receiving cavity 1 along the direction from the opening of the piston body to the piston top; it also includes a fixing structure for fixing the piston pin.

[0029] The above solution is the core solution of this embodiment. It is based on the existing piston body, but changes the structure of the piston pin 4 installed on the piston body, and then changes the structure of the corresponding part of the piston pin 4 accordingly. Other structures are not specifically improved and can be implemented by referring to the existing piston body.

[0030] Specifically, the structure of the piston pin seat 2 is not specifically limited. In this embodiment, it is a structure that protrudes on the side wall of the accommodating cavity 1. The existing piston pin seat shape design can be referenced, and the structure of the piston pin hole can be changed accordingly. At the same time, the swing of the connecting rod can be maintained.

[0031] In one embodiment, the receiving groove 3 includes at least one arc-shaped sidewall. The number of sidewalls is not specifically limited, but it includes at least three sidewalls. In this embodiment, for example... Figure 2 As shown, the sidewalls include four surfaces, specifically one arc-shaped sidewall and three flat sidewalls, with a U-shaped cross-sectional structure. The arc-shaped sidewall is positioned away from the opening of the piston body.

[0032] In one embodiment, the sidewalls of the receiving groove 3 are planar structures. The number of sidewalls is not specifically limited, but at least three planar sidewalls are included. In this embodiment, it includes four planar sidewalls. The cross-sectional structure is U-shaped, or more specifically, it is a flat replacement of the U-shaped structure, that is, the curved sidewalls are replaced with planar sidewalls.

[0033] The main body of the piston pin 4 is generally adapted for connecting rod connections, and existing technologies can be referenced; the structure of the insertion end 5 of the piston pin 4 is not specifically limited, as long as it can ensure that at least part of it is located within the receiving groove 3. Preferably, the insertion end 5 is fitted into the receiving groove 3. Preferably, after the insertion end 5 is placed into the receiving groove 3, there is still a certain amount of free space remaining. In this embodiment, the insertion end 5 matches the structure of the U-shaped receiving groove 3, which is composed of a flat square plane and an arc-shaped surface in the circumferential direction, such as... Figure 3 As shown.

[0034] As for the fixing structure of the piston pin 4, no specific limitations are imposed, as long as it can fix the piston pin 4 after the insertion end 5 is placed into the receiving groove 3. The fixing structure can refer to existing fixing screws or other fixing structures for the piston pin 4. In this embodiment, the fixing structure includes a stop 6 that fits against the insertion end 5 and has a through hole, and a fixing member for fixing the stop 6. The through hole of the stop 6 should preferably not affect the swing of the connecting rod, as specifically referred to Figure 4 The stop 6 is fitted with the insertion end 5. Specifically, the stop 6 is pushed along the direction from the opening of the piston body to the piston top to the piston pin seat 2 to fit with the insertion end 5. This fitting structure is determined according to the structure of the insertion end 5 at the receiving groove 3. In this embodiment, a stop block 9 is formed on the stop 6 that can extend into the receiving groove 3. The stop block 9 fits with the insertion end 5. As for the fitting surface, there is no specific limitation, but a plane is preferred. The automatic component 6, excluding the part of the stop block 9, has a clearance fit with the piston pin seat 2 to avoid machining errors that cause the stop block 9 to be unstable or unable to fit with the insertion end 5. More preferably, after the stop block 9 extends into the receiving groove 3, in addition to fitting with the insertion end 5, it at least partially fits with the receiving groove 3.

[0035] As for the fastener, there is no specific limitation, as long as it can secure the stop 6. In this embodiment, the fastener is a fixing body 7 with external threads and a through hole. The external threads are not shown in the figure, and their location is... Figure 5 In part A, the through hole of the fixing body 7 should be designed so as not to affect the swing of the connecting rod. See reference [link / reference needed] for details. Figure 5 Simultaneously, the accommodating cavity 1 forms an internal thread adapted to the external thread, which is not shown in the diagram, and its location is... Figure 2 In part B, the fixing body 7 is screwed into the internal thread and fitted to the stop 6. Furthermore, a groove 8 is formed on the fixing body 7, and the piston body is riveted at the position of the groove 8. The deformed structure after riveting is embedded in the groove 8. The number of grooves 8 is not specifically limited. In this embodiment, two symmetrically arranged grooves are preferred.

[0036] The assembly process of this utility model is as follows: the stop 6 and the fixing body 7 are fitted onto the connecting rod, then the piston pin 4 is installed on the connecting rod, and then the end of the connecting rod with the piston pin 4 installed is inserted into the receiving cavity 1 of the piston body, so that the insertion end 5 of the piston pin 4 is inserted into the receiving groove 3. The stop 6 is pushed until the stop block 9 is inserted into the receiving groove 3 and fits against the insertion end 5. The fixing body 7 is pushed to the internal thread and the fixing body 7 is tightened. The corresponding position of the piston body is punched and riveted so that the deformed structure is embedded in the groove 8.

[0037] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A piston with a composite fixed piston pin, characterized in that, The device includes a piston body, a receiving cavity formed within the piston body, two opposing piston pin seats formed on the sidewall of the receiving cavity, a receiving groove formed on each piston pin seat, the opening of the receiving groove being located within the receiving cavity, and two ends of the piston pin forming insertion ends that match the receiving groove, at least a portion of the insertion ends being located within the receiving groove; it also includes a fixing structure for fixing the piston pin.

2. The piston with a composite fixed piston pin of claim 1, wherein, The receiving groove includes at least three planar sidewalls.

3. The piston with a composite fixed piston pin of claim 2, wherein, The accommodating groove has a U-shaped structure.

4. The piston with a composite fixed piston pin of claim 1, wherein, The receiving groove includes at least one arc-shaped sidewall.

5. The piston with a composite fixed piston pin of claim 4, wherein, The accommodating groove has a U-shaped structure.

6. The piston with a composite fixed piston pin according to any one of claims 1-5, characterized in that, The insertion end is fitted into the receiving groove.

7. The piston with a composite fixed piston pin according to any one of claims 1-5, characterized in that, The fixing structure includes a stop member that fits against the insertion end and has a through hole, and a fixing member that fixes the stop member.

8. The piston with a composite fixed piston pin of claim 7, wherein, The fixing member is a fixing body with external threads and a through hole. The side wall of the accommodating cavity forms an internal thread that matches the external threads. After the fixing body is screwed into the internal threads, it fits against the stop member.

9. The piston with a composite fixed piston pin of claim 8, wherein, The fixing body has grooves formed on it to accommodate the deformed structure of the piston body after it has been punched and riveted.

10. The piston with a composite fixed piston pin of claim 7, wherein, The stop member has a stop block formed on it that can extend into the receiving groove and fit against the insertion end.

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