Piston structure for compressor and rotary compressor
By designing a new piston structure with shaft holes and clamping positions in the piston structure of the rotary compressor, and using the internal support clamp to achieve single-use fine grinding, the problem of difficult to ensure the piston dimensional accuracy is solved and the compressor is improved energy efficiency and sealing.
Patent Information
- Application Number
- CN202420277804.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-02-04
- Publication Date
- 2025-02-14
- Estimated Expiration
- 2034-02-04
AI Technical Summary
In the existing rotary compressors, the dimensional accuracy of the piston and the crankshaft is difficult to ensure, resulting in low energy efficiency of the compressor, and the coaxiality of the inner and outer diameters of the piston is difficult to control, affecting the assembly accuracy of the piston and other components.
A new piston structure is designed, including an axial hole that penetrates the axial direction in the middle of the piston body, and a clamping position is provided at both ends of the piston body. The clamping position is connected to the shaft hole and is passed through an internal support clamp and clamping position. Cooperate to achieve single-use clamping to complete the precision grinding of the piston structure.
Through this method, positioning errors caused by multiple clamping are avoided, the machining accuracy of the piston is improved, the coaxiality of the inner and outer diameters of the piston is ensured, and the energy efficiency and sealing of the compressor are improved.
Smart Images
Figure CN222478949U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of compressors, in particular to a piston structure for a compressor and a rotary compressor. Background Art
[0002] In the current refrigeration industry, rotary compressors are widely used in temperature regulation industries such as air conditioners, refrigerators, heat pumps, etc. due to their excellent comprehensive performance. In the current rotary compressor assembly process, the gap between the inner diameter of the compressor cylinder and the outer diameter of the piston is the largest leakage line in the compression chamber when the compressor is running. The size of this gap directly affects the energy efficiency of the compressor, and the inner diameter size of the compression machine cylinder, the inner and outer diameter sizes of the piston and the dimensional accuracy of the crankshaft are the direct factors affecting the gap. However, in the current processing technology of the industry, the dimensional accuracy of the piston and the crankshaft is the most difficult to guarantee, especially the thickness size of the difference between the inner and outer diameters of the piston and the cumulative error of the crankshaft.
[0003] In the existing rotary compressor structure, the piston is designed as an internal hollow cylinder. Due to the limitation of processing technology, the inner and outer diameter coaxiality of the piston of this structure is difficult to effectively control, resulting in a large difference in the uniformity of the active wall thickness. The processing method of the piston of this structure is: rough processing---heat treatment---fine grinding of the outer circle---fine grinding of the inner circle---double end surface fine grinding---packaging. Its structure is limited by the processing technology, so the processing of the outer circle and the inner circle is step-by-step, which makes it difficult to control the inner and outer diameter coaxiality. The unstable progress of the piston size will affect the assembly accuracy of the piston and other components, so that the energy efficiency of the compressor cannot be improved well. Utility Model Content
[0004] Based on this, it is necessary to provide a piston structure for a compressor and a rotary compressor that can achieve better processing accuracy.
[0005] The utility model provides a piston structure for a compressor, comprising a piston main body, wherein the middle part of the piston main body is provided with an axial hole penetrating along the axial direction, the piston main body is provided with a first end face and a second end face at both ends along the axial direction, the piston main body comprises, from the inside to the outside, a main body inner wall and a main body outer wall surrounding the axial hole, the piston main body is also provided with a clamping position, the clamping position is arranged between the first end face and the second end face, the clamping position is formed by a depression at the main body inner wall toward the main body outer wall, and the clamping position is communicated with the axial hole.
[0006] Preferably, the clamping position includes a step bottom surface and a step side wall that are connected to each other, the step side wall is located between the step bottom surface and the second end surface, the step side wall is closer to the main body outer wall relative to the main body inner wall, the step side wall extends from near the step bottom surface to pass through the second end surface, and the average width of the second end surface is smaller than the average width of the first end surface.
[0007] Preferably, the distance between the bottom surface of the step and the second end surface is smaller than the distance between the bottom surface of the step and the first end surface.
[0008] Preferably, the clamping position is further provided with a tool retreat groove, which is located between the bottom surface of the step and the side wall of the step and is recessed relative to the side wall of the step toward the outer wall of the main body.
[0009] Preferably, the clamping position is arranged around the inner wall of the main body.
[0010] Preferably, a plurality of the clamping positions are provided, and the plurality of clamping positions are arranged at intervals around the inner wall of the piston body.
[0011] Preferably, a first chamfer is connected between the first end surface and the inner wall of the main body, and a second chamfer is connected between the step side wall and the second end surface.
[0012] The utility model also provides a rotary compressor, including a compressor pump body, the compressor pump body including a crankshaft structure, a piston structure, a sliding vane, a cylinder and a main bearing, the piston structure is the piston structure for the above-mentioned compressor, the crankshaft structure, the piston and the cylinder are arranged in sequence from the inside to the outside, and the crankshaft is installed in the axial hole of the piston.
[0013] Preferably, the outer wall of the crankshaft abuts against the inner wall of the main body, and there is a gap between the outer wall of the crankshaft and the side wall of the step.
[0014] The new piston structure in this patent can realize the fine grinding of the main body outer wall, main body inner wall and one of the end faces of the inner piston structure under the premise of one-time clamping, avoiding the positioning error caused by multiple clamping and making the piston processing accuracy better. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The above and other purposes, features and advantages of the present invention will become clearer through a more specific description of the preferred embodiments of the present invention shown in the accompanying drawings. The same reference numerals indicate the same parts in all the accompanying drawings, and the accompanying drawings are not deliberately scaled to the actual size, but the focus is on illustrating the main purpose of the present invention.
[0016] Figure 1 This is a schematic diagram of the three-dimensional structure of the piston provided in the first embodiment of the utility model.
[0017] Figure 2 This is a schematic diagram of the cross-sectional structure of a piston provided in the first embodiment of the utility model.
[0018] Figure 3 This is a schematic diagram of the three-dimensional structure of the piston provided in the second embodiment of the utility model.
[0019] Figure 4 This is a schematic diagram of the top view of the piston provided in the second embodiment of the utility model.
[0020] Figure 5 This is a schematic diagram of the matching structure of the piston and the inner support clamp provided by the utility model.
[0021] Figure 6 This is a schematic diagram of the structure of the pump body assembly provided by the utility model.
[0022] Figure 7 for Figure 6 Enlarged schematic diagram of part "A" in the figure.
[0023] 1-crankshaft structure, 2-piston structure, 21-clamping position, 211-step bottom surface, 212-step side wall, 213 backing groove, 22-second end surface, 23-first end surface, 24-shaft hole, 25-main body outer wall, 26-main body inner wall, 3-cylinder, 4-main bearing, 5-inner support fixture, 51-inner support. DETAILED DESCRIPTION
[0024] In order to facilitate the understanding of the present invention, a more comprehensive description of the present invention will be given below with reference to the relevant drawings.
[0025] It should be noted that when an element is considered to be "connected" to another element, it may be directly connected to another element and integrated therewith, or there may be an intermediate element at the same time. The terms "installed", "one end", "the other end" and similar expressions used herein are for illustrative purposes only.
[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art. The terms used in the specification herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.
[0027] refer to Figure 1-5 The utility model provides a piston structure 2 for a compressor, including a piston body, a shaft hole 24 penetrating axially in the middle of the piston body, a first end face 23 and a second end face 22 are arranged at both ends of the piston body along the axial direction, and the piston body includes a main body inner wall 26 and a main body outer wall 25 that surround the shaft hole 24 from the inside to the outside. The piston body is also provided with a clamping position 21, and the clamping position 21 is arranged between the first end face 23 and the second end face 22. The clamping position 21 is formed by a depression at the main body inner wall 26 toward the main body outer wall 25, and the clamping position 21 is communicated with the shaft hole 24.
[0028] In the existing rotary compressor structure, the piston is designed as an internal hollow cylinder. Due to the limitation of the processing technology, the coaxiality of the inner and outer diameters of the piston of this structure is difficult to effectively control, resulting in a large difference in the uniformity of the wall thickness. In the existing piston processing, the fine grinding of the outer circle (outer wall of the main body), the inner circle (inner wall of the main body) and the end face is carried out in steps, which requires multiple clamping, resulting in the difficulty in effectively controlling the coaxiality of the inner and outer diameters of the piston.
[0029] The piston structure 2 for the compressor provided by the utility model can realize the fine grinding of the main body outer wall 25, the main body inner wall 26 and one of the end faces of the inner piston structure 2 under the premise of one-time clamping through the clamping position 21. It avoids the positioning error caused by multiple clamping, so that the inner and outer diameter dimensional accuracy of the piston structure 2 is better controlled, ensuring that the coaxiality difference between the inner and outer circles of the piston structure 2 is relatively small, so that the matching of the crankshaft and the piston structure 2 can be better guaranteed, reducing the cumulative error, and further ensuring the tightness of the matching tangent surface between the inner diameter of the compressor cylinder and the outer diameter of the piston 2 when the compressor is assembled, avoiding leakage, and improving the energy efficiency of the compressor.
[0030] refer to Figure 1-5 The precision grinding method of the piston structure 2 provided by the utility model is: S1, match the inner support clamp 5 with the clamping position 21, specifically: extend the inner support 51 of the inner support clamp 5 into the clamping position 21 of the piston 2, drive the inner support 51 to move and expand through components such as pull rods, and match with the clamping position 21 set by the inner diameter of the piston 2, clamp and fix the piston 2, and use the clamping position 21 as the clamping reference to perform precision grinding or semi-precision grinding on the main body outer wall 25, the main body inner wall 26 and the first end face 23; S2, use the processed first end face 23 as the reference to perform precision grinding on the second end face 22. The novel piston 2 structure provided by the utility model enables the fine grinding of the main body outer wall 25, the main body inner wall 26 and one of the end faces of the inner piston 2 to be completed under the premise of one-time clamping. Because the working surfaces of the main body outer wall 25 and the main body inner wall 26 of the piston structure 2 are completed by one-time clamping, the problem of large difference in coaxiality of the inner and outer circles of the piston 2 and uneven wall thickness caused by secondary or multiple clamping positioning errors is avoided, and the wall thickness accuracy of the piston 2 is controlled within the tolerance range of ±0.002MMw.
[0031] In a preferred embodiment, the piston 2 further includes the steps of rough machining and heat treatment before the fine grinding.
[0032] refer to Figure 1-5In a preferred embodiment, in step S1, the main body outer wall 25, the main body inner wall 26 and the first end face 23 are all finely ground. In another preferred embodiment, step S1 specifically includes: the inner support fixture 5 is matched with the clamping position 21, and the clamping position 21 is used as the clamping reference, and the main body outer wall 25 and the first end face 23 are finely ground to the finished product value, and the main body inner wall 26 is finely ground with a margin of 0.01-0.05mm; after step S2, it also includes the step of hinged truss, and the step of hinged truss is: the finely machined first end face 23 and the main body outer wall 25 are clamped to the floating plate as the reference, and the inner circle after semi-fine grinding is used as the positioning surface to perform hinged truss fine grinding on the inner circle.
[0033] refer to Figure 1-5 In a preferred embodiment, the preparation method of the piston 2 is:
[0034] (1) Rough machining: The blank is turned into a workpiece with a certain margin, especially the inner diameter of the piston 2 in the new structure is fine-turned to obtain a relatively uniform and stable size.
[0035] (2) Heat treatment: Use existing general technology to enhance the strength of the piston 2.
[0036] (3) Fine grinding of the main body outer wall 25 (outer circle) / semi-fine grinding of the main body inner wall 26 (inner circle) / fine grinding of the first end face 23: the inner support 51 of the inner support clamp 5 is extended into the clamping position 21 of the piston 2, and the inner support 51 is driven by components such as a pull rod to move and expand, and cooperates with the clamping position 21 set by the inner diameter of the piston 2 to clamp and fix the piston 2. With the clamping position 21 as the clamping reference, the outer wall 25 and the first end face 23 of the piston 2 are finely ground and processed to the finished product value, and then the inner wall 26 of the main body is semi-finished with a margin of 0.01-0.05mm. In this process step, the processing of three working surfaces is achieved through one-time clamping, thereby avoiding excessive coaxiality between the inner hole and the outer circle caused by secondary clamping, and at the same time, the verticality of the inner / outer circle of the piston 2 and the processed end is guaranteed.
[0037] (4) Fine grinding of the second end face 22: The second end face 22 on the side of the clamping position 21 is finely ground to a set size based on the finely ground first end face 23. Since the finely ground working surface is used as the positioning and clamping reference, it is ensured that the end face processed in this step can be perpendicular to the inner hole / outer circle of the piston 2 within the designed range.
[0038] (5) Hinge truss: The first end face 23 after fine machining and the outer wall 25 of the main body are clamped to the floating plate as the reference, and the inner wall 26 of the main body after semi-fine grinding is used as the positioning surface to perform fine grinding on the inner wall 26 of the main body. Due to the adaptive characteristics of the grinding rod and the floating chuck of the hinge truss, the coaxiality of the inner circle after the grinding of the truss with respect to the outer circle and the perpendicularity to the two end faces are guaranteed.
[0039] (6) Packaging: Anti-collision compartment packaging.
[0040] refer to Figure 1-5 In a preferred embodiment, the clamping position 21 includes a step bottom surface 211 and a step side wall 212 connected to each other. The step side wall 212 is located between the step bottom surface 211 and the second end surface 22. The step side wall 212 is closer to the main body outer wall 25 than the main body inner wall 26. The step side wall 212 extends from the step bottom surface 211 to the second end surface 22 upward, so that the width of the second end surface at the clamping position is thinned. The second end surface width of the piston structure 2 provided in this embodiment is narrowed at the clamping position, so that the average width of the second end surface 22 is smaller than the average width of the first end surface 23. The internal support clamp 5 can easily extend from the second end surface 22 into the clamping position for clamping and fixing.
[0041] refer to Figure 1-5 In a preferred embodiment, the distance between the step bottom surface 211 and the second end surface 22 is smaller than the distance between the step bottom surface 211 and the first end surface 23 .
[0042] refer to Figure 2 In a preferred embodiment, the clamping position 21 is further provided with a tool retreat groove 213 , which is located between the step bottom surface 211 and the step side wall 212 , and is recessed relative to the step side wall 212 toward the main body outer wall 25 .
[0043] refer to Figure 1-5 In a preferred embodiment, the ratio of the average width of the step bottom surface 211 to the average width of the first end surface 23 is 1:(1.2-2).
[0044] refer to Figure 1-2 In a preferred embodiment, the clamping position 21 is arranged around the inner wall 26 of the main body.
[0045] refer to Figure 3-4 There are multiple clamping positions 21, and the multiple clamping positions 21 are arranged at intervals around the inner wall 26 of the piston body.
[0046] refer to Figure 1-5 In a preferred embodiment, a first chamfer is connected between the first end face 23 and the inner wall 26 of the main body, and a second chamfer is connected between the step side wall 212 and the second end face 22 .
[0047] The utility model also provides a rotary compressor, including a compressor pump body, the compressor pump body including a crankshaft structure 1, a piston structure 2, a sliding vane 9, a cylinder 3 and a main bearing 4, the piston structure 2 is the piston structure 2 mentioned in any of the above embodiments, the crankshaft structure 1, the piston 2 and the cylinder 3 are arranged in sequence from the inside to the outside, the crankshaft structure 1 is installed in the shaft hole 24 of the piston structure 2,
[0048] When the compressor provided by the utility model is in operation, the piston is eccentrically driven by the crankshaft 1 so that the outer diameter of the piston 2 and the inner diameter of the cylinder 3 are rolling tangent, and the suction chamber 91 and the compression chamber 92 are alternately and independently operated in combination with the separation of the sliding vane 9. The compressor provided by the utility model reduces the error of assembly control, so that the inner diameter of the cylinder 3 and the tangent surface C of the piston 2 have better sealing performance, and the gap of the tangent surface C is reduced to ensure that the compression chamber leaks less to the suction chamber, which greatly improves the energy efficiency of the compressor.
[0049] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.
[0050] In the description of this specification, the description with reference to the terms "preferred embodiment", "further embodiment", "other embodiments" or "specific example" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.
[0051] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.
Claims
1. A piston structure for a compressor, characterized in that: It includes a piston body, the middle part of which has an axial hole passing through it axially, and the two ends of the piston body along the axial direction are provided with a first end face and a second end face, and the piston body includes, from the inside to the outside, a main body inner wall and a main body outer wall that surround the axial hole, and the piston body is also provided with a clamping position, which is arranged between the first end face and the second end face, and the clamping position is formed by a depression on the inner wall of the main body toward the outer wall of the main body, and the clamping position is communicated with the axial hole.
2. The piston structure for a compressor according to claim 1, characterized in that: The clamping position includes a step bottom surface and a step side wall that are interconnected, the step side wall being located between the step bottom surface and the second end surface, the step side wall being closer to the main body outer wall than the main body inner wall, the step side wall extending from near the step bottom surface to passing through the second end surface, and the average width of the second end surface being smaller than the average width of the first end surface.
3. The piston structure for a compressor according to claim 2, characterized in that: The distance between the bottom surface of the step and the second end surface is smaller than the distance between the bottom surface of the step and the first end surface.
4. The piston structure for a compressor according to claim 2, characterized in that: The clamping position is further provided with a tool retreat groove, which is located between the bottom surface of the step and the side wall of the step and is recessed relative to the side wall of the step toward the outer wall of the main body.
5. The piston structure for a compressor according to claim 1, characterized in that: The clamping position is arranged around the inner wall of the main body.
6. The piston structure for a compressor according to claim 1, characterized in that: There are a plurality of clamping positions, and the plurality of clamping positions are arranged at intervals around the inner wall of the piston body.
7. The piston structure for a compressor according to claim 1, characterized in that: The clamping position includes a step bottom surface and a step side wall connected to each other, a first chamfer is connected between the first end surface and the inner wall of the main body, and a second chamfer is connected between the step side wall and the second end surface.
8. A rotary compressor, characterized in that: It comprises a compressor pump body, which comprises a crankshaft structure, a piston structure, a vane, a cylinder and a main bearing. The piston structure is the piston structure for a compressor as described in any one of claims 1 to 7. The crankshaft structure, the piston and the cylinder are arranged in sequence from the inside to the outside, and the crankshaft is installed in the axial hole of the piston.
9. The rotary compressor according to claim 8, characterized in that The outer wall of the crankshaft abuts against the inner wall of the main body, and a gap is provided between the outer wall of the crankshaft and the step side wall.