A wobble piston assembly and an oil-free wobble piston air compressor

Abstract

The utility model discloses a kind of swing piston assemblies, including integrated piston part and connecting rod part, the side wall of the piston part forms annular groove;Still including the wear ring of leather cup type sealing of PEEK material, the wear ring of leather cup type sealing is formed on the piston part by injection molding, by changing the fixed mode of wear ring of leather cup type sealing, it is changed to integrally formed structure after injection molding by the fixed connection mode of bolt and pressing plate, the gap caused by wear ring of leather cup type sealing pulling deformation between wear ring of leather cup type sealing and piston head is avoided, to avoid the phenomenon that the connecting place between bottom ring and side ring is collided due to gap. The utility model also discloses oil-free swing piston type air compressor using the above-mentioned swing piston assembly.

Description

Technical Field

[0001] This utility model relates to the field of piston technology, specifically to a rocking piston assembly and an oil-free rocking piston air compressor. Background Technology

[0002] Oil-free rotary piston air compressors are frequently used in vehicle-mounted air pumps, small medical oil-free air compressors, and indoor silent oil-free air compressors due to their simple structure and low cost.

[0003] Currently, the most common oil-free swing piston air compressors on the market use a cup-shaped structure as a sealing wear ring to compress gas. The cup-shaped sealing wear ring is generally made of PTFE material. It is formed into a "cup" shape by bending or stamping the original sheet or plate shape, and then fixed to the swing piston by metal pressure plate and fixing bolts.

[0004] Due to material properties and molding process, the cup-type wear-resistant sealing rings made of PTFE material have uniform thickness. However, because they are fixed by pressing the bottom ring with a pressure plate, micro-gaps are formed between the cup-type wear-resistant sealing ring, the pressure plate, and the swing piston at the periphery of the pressure plate during the movement of the ring following the swing piston. These gaps cause repeated impacts between the cup-type wear-resistant sealing ring and the pressure plate and swing piston, which can easily lead to tearing at the root (the connection between the bottom ring and the side ring). This results in the failure of the cup-type wear-resistant sealing ring's sealing function, ultimately causing the entire air compressor to fail. Utility Model Content

[0005] To solve the above-mentioned technical problems, this utility model provides a rocker piston assembly, including an integral piston part and a connecting rod part, wherein the side wall of the piston part forms an annular groove; it also includes a PEEK cup-type sealing wear-resistant ring, which is formed on the piston part by injection molding. The cup-type sealing wear-resistant ring includes a bottom ring and a side ring connected to the bottom ring. The bottom ring is located in the annular groove, and the side ring is formed around the piston head of the piston part; the thickness of the bottom ring is greater than the thickness of the side ring, and the thickness at the connection between the bottom ring and the side ring gradually decreases from the bottom ring to the side ring. By changing the fixing method of the cup-type seal wear ring from bolt and pressure plate to an injection-molded integrated structure, gaps caused by the tensile deformation of the cup-type seal wear ring between the wear ring and the piston head are avoided. This prevents collisions at the connection between the bottom ring and the side ring due to gaps. Furthermore, by designing the thickness of the bottom ring to be greater than that of the side ring, and the thickness of the connection between the bottom ring and the side ring gradually thinning from the bottom ring to the side ring, the cup-type seal wear ring deforms mostly at the connection due to the tensile stress caused by the movement of the piston, greatly reducing tearing at the connection. This reduces or avoids the failure of the cup-type seal wear ring's sealing function, thus ensuring the effective use of the air compressor.

[0006] Furthermore, the thickness of the alternating compression portion on the side ring of the cup-type sealing wear-resistant ring is greater than the thickness of other portions.

[0007] Specifically, the alternating compression portion is symmetrical about the midpoint A of the piston portion and the connecting rod portion, and the thickness of the alternating compression portion gradually decreases from the midpoint of the symmetrical surface to both sides.

[0008] During the operation of the rocking piston, the piston section will tilt in two fixed directions. Specifically, these two directions are the directions in which the connecting rod section points during its rocking motion. In these two directions, the cup-type seal wear ring must not only ensure an overall seal, but also withstand the compressive force of the connecting rod section in these two directions. By setting the thickness of the alternately compressed part to be greater than the thickness of other parts, the wear of that part can be reduced indirectly, ensuring the overall effectiveness of the cup-type seal wear ring, improving the service life of the cup-type seal wear ring, and ensuring the effective operation of the air compressor.

[0009] Furthermore, multiple air intake channels are formed on the piston section, and an annular muffler block is provided at the upper end of the piston head for each air intake channel. The annular muffler block is made of PEEK material.

[0010] Furthermore, the annular muffler block is formed on the piston head by injection molding.

[0011] Furthermore, a fixing hole is formed at the upper end of the piston head; it also includes an intake valve plate adapted to the intake passage and a fixing bolt adapted to the fixing hole and the intake valve plate.

[0012] By changing the material of the intake passage located at the upper end of the piston head, even during the periodic opening and closing of the intake valve plate during the operation of the rocking piston, the sound of the intake valve plate striking the annular silencer block made of PEEK material is much less than the sound of the intake valve plate striking the piston head (made of metal), thus reducing noise. Furthermore, the annular silencer block is injection molded onto the piston head, reducing fixed parts and simplifying the equipment and its installation.

[0013] This utility model also discloses an oil-free swing piston air compressor, which includes the aforementioned swing piston assembly, thereby ensuring the overall effectiveness of the oil-free swing piston air compressor and reducing noise during use. Attached Figure Description

[0014] 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.

[0015] Figure 1 This is a schematic diagram of the structure of the rocking piston assembly of this utility model;

[0016] Figure 2 This is a cross-sectional structural schematic diagram of the rocking piston assembly of this utility model;

[0017] Figure 3 This utility model relates to a leather cup-type sealing wear-resistant ring;

[0018] Figure 4 This is a schematic diagram of the structure of the rocking piston assembly (including the intake valve plate) of this utility model;

[0019] Figure 5 This is a schematic diagram of the structure of the rocking piston assembly of this utility model located inside the cylinder;

[0020] The reference numerals in the figure are as follows: 1-Piston section; 2-Connecting rod section; 3-Annular groove; 4-Wear-resistant ring with a cup seal; 6-Bottom ring; 5-Piston head; 7-Side ring; 8-Alternating compression part; 9-Intake passage; 10-Annular muffler block; 11-Fixing hole; 12-Intake valve plate; 13-Fixing bolt; 14-Cylinder block; 15-Valve plate; 16-Exhaust valve; 17-Cylinder head. Detailed Implementation

[0021] 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.

[0022] 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.

[0023] 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.

[0024] 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.

[0025] Example 1

[0026] like Figure 1-4 As shown, this embodiment discloses a rocker piston assembly, which includes an integral piston portion 1 and a connecting rod portion 2. An annular groove 3 is formed on the side wall of the piston portion 1. It also includes a PEEK cup-type wear-resistant sealing ring 4, which is formed on the piston portion 1 by injection molding. Specifically, the cup-type wear-resistant sealing ring 4 includes a bottom ring 6 and a side ring 7 connected to the bottom ring 6. The shapes of the bottom ring 6 and the side ring 7 can be formed with reference to the structure of existing cup-type wear-resistant sealing rings. In this embodiment, the thickness of the bottom ring 6 is greater than the thickness of the side ring 7. Moreover, the thickness at the connection between the bottom ring 6 and the side ring 7 is not uniform but varies. Specifically, from the bottom ring 6 to the side ring 7, the thickness at the connection gradually decreases, that is, the thickness of the bottom ring 6 gradually transitions to the thickness of the side ring 7. During injection molding, the bottom ring 6 is formed in the annular groove 3, and the side ring 7 is formed around the piston head 5 of the piston portion 1, but does not fit tightly against the piston head 5, having a certain gap.

[0027] Furthermore, the thickness of the alternating compression portion 8 on the side ring 7 of the cup-type seal wear ring 4 is greater than the thickness of other portions. The alternating compression portion 8 is the part where the connecting rod 2, during its oscillation process, pushes the cup-type seal wear ring 4 against the cylinder sidewall, and there are two symmetrical alternating compression portions 8 according to the oscillation direction of the connecting rod 2. More specifically, the alternating compression portion 8 is located at the midpoint A between the piston portion 1 and the connecting rod portion 2 (see...). Figure 2 The thickness of each alternately compressed part 8 gradually decreases from the plane of symmetry to both sides until the thickness of the side ring 7 is reached.

[0028] Multiple air intake channels 9 are formed on the piston section 1. An annular muffler block 10 is provided at the upper end of the air intake channel 9 and the annular muffler block 10 is made of PEEK material. Further, the annular muffler block 10 is formed on the piston head 5 by injection molding. A fixing hole 11 is also formed at the upper end of the piston head 5. The fixing hole 11 is a threaded hole and includes an air intake valve plate 12 adapted to the air intake channel 9 and a fixing bolt 13 adapted to the fixing hole 11 and the air intake valve plate 12. In this embodiment, there are 4 air intake channels 9 arranged in a cross shape, and the air intake valve plate 12 is also arranged in a cross shape. The air intake valve plate 12 is fixed by screwing the fixing bolt 13 into the fixing hole 11.

[0029] Example 2

[0030] This embodiment discloses an oil-free swing piston air compressor, which includes the swing piston assembly described in Embodiment 1, with reference to... Figure 5 The rocker piston assembly is installed inside the cylinder 14, wherein the wear-resistant ring 4 of the cup seal is fitted with the inner wall of the cylinder 14 to achieve a seal. A valve plate 15 and an exhaust valve 16 are arranged on the valve plate 15 above the cylinder 14, and the cylinder head 17 is arranged above the valve plate 15 to form an exhaust passage.

[0031] 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 rocking piston assembly, characterized in that, The device includes an integral piston and connecting rod, with the sidewall of the piston forming an annular groove. It also includes a PEEK cup-type wear-resistant sealing ring, which is injection molded onto the piston. The cup-type wear-resistant sealing ring includes a bottom ring and a side ring connected to the bottom ring. The bottom ring is located in the annular groove, and the side ring is formed around the piston head of the piston. The thickness of the bottom ring is greater than the thickness of the side ring, and the thickness at the connection between the bottom ring and the side ring gradually decreases from the bottom ring to the side ring.

2. The rocking piston assembly according to claim 1, characterized in that, The thickness of the alternating compression portion on the side ring of the cup-type sealing wear-resistant ring is greater than the thickness of other portions.

3. The rocking piston assembly according to claim 2, characterized in that, The alternating compression section is symmetrical about the midpoint A between the piston section and the connecting rod section, and the thickness of the alternating compression section gradually decreases from the midpoint of the symmetrical surface to both sides.

4. The rocking piston assembly according to claim 1, characterized in that, Multiple air intake channels are formed on the piston section, and an annular muffler block is provided at the upper end of the piston head for each air intake channel. The annular muffler block is made of PEEK material.

5. The rocking piston assembly according to claim 4, characterized in that, The annular silencing block is formed on the piston head by injection molding.

6. The rocking piston assembly according to claim 4, characterized in that, A fixing hole is formed at the upper end of the piston head; it also includes an intake valve plate adapted to the intake passage and a fixing bolt adapted to the fixing hole and the intake valve plate.

7. An oil-free swing piston air compressor, characterized in that, It includes the rocking piston assembly as described in any one of claims 1-6.

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