Wobble plate type compressor

Abstract

The utility model provides a wobble plate type compressor, which comprises a cylinder body, a swing plate, a swing plate and a swing plate, the fixed gear is arranged in the cylinder body, and an inner hole key groove is formed in the inner wall of a center hole of the fixed gear; the gear key comprises a base part embedded into the inner hole key groove and a head part embedded into the cylinder body key groove, and the gear key connects the fixed gear and the cylinder body through the base part and the head part so as to prevent relative rotation; the section profile of the cylinder block key groove comprises at least one side wall which is inclined relative to the radial direction of the fixed gear. Moreover, the head part of the gear key is provided with an inclined side surface matched with the inclined side wall of the cylinder body key groove, so that the inclined side surface of the head part is mainly contacted with the inclined side wall of the cylinder body key groove when the gear key bears torque. Reliability and durability of fixed gear connection are remarkably improved, and the technical problem that in the prior art, a key groove is prone to damage, and consequently performance of a compressor is reduced or fails is solved.

Description

Technical Field

[0001] This utility model relates to air compressors, and more particularly to a swivel-type compressor. Background Technology

[0002] Swing compressors, especially variable displacement or constant displacement swing compressors widely used in automotive air conditioning systems, are favored for their compact structure, stable operation, and high efficiency. Their basic working principle typically involves a rotating main shaft driving a swashplate or swing disk, which in turn drives a piston in a reciprocating motion within the cylinder, completing the refrigerant intake, compression, and discharge processes. In this type of compressor, to achieve specific motion conversion and gas distribution functions, it contains various precisely matched moving and stationary components. For example, the planetary disk assembly (or swing disk) performs complex swinging motion under the drive of the main shaft, while its swing gear meshes with a fixed gear (or fixed gear ring) that remains stationary relative to the cylinder block to achieve the correct motion posture of the planetary disk assembly (e.g., preventing it from rotating entirely on its own axis, only swinging). Therefore, reliably fixing the fixed gear to the cylinder block and preventing it from rotating or displacing when subjected to the meshing force from the planetary disk assembly's swing gear is one of the key technologies for ensuring the normal, stable, and long-term operation of the compressor.

[0003] To achieve relative fixation between components or prevent undesirable rotation, various connection or anti-rotation structures are employed in the prior art. For example, Chinese Utility Model Patent Publication CN2782980Y discloses a planetary disk anti-rotation mechanism in a swashplate compressor. This solution aims to address the rotation problem of the planetary disk relative to a fixed disk. The technical solution includes: a fixed anti-rotation ball with a key pin on the fixed disk; correspondingly, a spherical recess corresponding to the anti-rotation ball is formed on the planetary disk, with a pin groove corresponding to the key pin within the recess. The anti-rotation ball's spherical fit with the recess, and the key pin's insertion into the pin groove, effectively constrain the planetary disk's rotation.

[0004] However, analysis of existing technologies reveals limitations in their structural design and connection methods, particularly under conditions of high torque, long-term operation, or specific material combinations, which may lead to reliability issues. Taking CN2782980Y as an example, although its application scenario (between the planetary disk and the fixed disk) differs from the connection between the fixed gear and the cylinder block that this invention focuses on, the "key-pin-groove" connection method used to transmit anti-rotation torque is similar. In this structure, the force preventing the planetary disk from rotating is ultimately transmitted through the key to the sidewall of the pin groove within the spherical recess of the planetary disk. Typically, to ensure strength and wear resistance, the key is made of a high-strength metal material (such as steel). The planetary disk itself, for lightweighting or other design considerations, may be made of a relatively soft material (such as aluminum alloy). When the compressor is running, the planetary disk is subjected to a force that tends to rotate, and this force is concentrated on the sidewall of the pin groove through the key. Because the contact surfaces of the key and the slot are typically simple geometries (such as planes or arc surfaces with small radii of curvature), and the presence of clearance can cause the key to tilt slightly under stress, contact stress easily concentrates near the opening edge or ridge of the slot. For planetary disks made of relatively soft materials, this highly concentrated contact stress can easily lead to plastic deformation, crushing, wear, or even breakage at the edge of the slot. Once the slot is damaged, the clearance between the key and the slot increases, weakening the anti-rotation effect, which may cause planetary disk instability, abnormal noise, and vibration. In severe cases, it may even cause the key to come off or break, resulting in serious malfunctions such as compressor seizure, significantly reducing the compressor's operational reliability and service life. Furthermore, metal debris generated by damaged slots may enter the compressor, contaminating the refrigerant system and accelerating the wear of other moving parts. Therefore, how to optimize this torque-transmitting connection structure, avoid stress concentration, and improve the reliability and durability of the connection, especially in situations where materials of different strengths are used together, is a technical problem that urgently needs to be solved in this field. Utility Model Content

[0005] The purpose of this invention is to provide a swivel-type compressor that optimizes the key connection structure between the fixed gear and the cylinder block to solve the problem in the prior art where stress concentration causes easy damage to the keyway, affecting the reliability and durability of the compressor.

[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows: A swivel-type compressor is provided, comprising: a cylinder block with a cylinder block keyway; a fixed gear disposed within the cylinder block, wherein an inner keyway is formed on the inner wall of the central hole of the fixed gear; a gear key comprising a base embedded in the inner keyway and a head embedded in the cylinder block keyway, wherein the gear key connects the fixed gear to the cylinder block through the base and the head to prevent relative rotation; wherein the cross-sectional profile of the cylinder block keyway includes at least one sidewall radially inclined relative to the fixed gear; and the head of the gear key has an inclined side surface adapted to the inclined side wall of the cylinder block keyway, such that when subjected to torque, the inclined side surface of the head mainly contacts the inclined side wall of the cylinder block keyway.

[0007] Preferably, the base of the gear key has a generally rectangular cross-section, and the inner keyway of the fixed gear is a rectangular slot adapted to the rectangular cross-section of the base, the base is embedded in the rectangular slot, and the head of the gear key extends from the base in a direction away from the fixed gear and is embedded in the cylinder block keyway.

[0008] Preferably, the cylinder block is made of aluminum alloy, and the gear key is made of high-strength steel; the cylinder block keyway is formed on the aluminum alloy cylinder block, and the steel head of the gear key is embedded in the aluminum alloy cylinder block keyway.

[0009] Preferably, it also includes a planetary disk component having a oscillating gear configured to mesh with the external teeth of the fixed gear; the fixed gear is connected to the cylinder block via the gear key to resist the tendency of the fixed gear to rotate when the oscillating gear meshes with the fixed gear.

[0010] Preferably, it further includes an adjusting screw, a spring, and a spring seat disposed between the adjusting screw and the spring; the adjusting screw, the spring seat, and the spring are arranged axially, with the adjusting screw adjacent to the spring seat; the gear key has an axial length that extends away from the end of the fixed gear and is axially adjacent to the spring seat or the other end of the spring.

[0011] The beneficial effects of this invention are as follows: By designing the cross-section of the cylinder block keyway to include radially inclined sidewalls, and giving the head of the gear key a matching inclined side surface, when the fixed gear rotates due to the meshing of the planetary disk components and transmits torque through the gear key, the inclined side surface of the gear key head can preferentially and primarily contact the inclined sidewall inside the cylinder block keyway. This structural design cleverly guides the contact stress from the easily damaged opening edges of the traditional rectangular keyway to the thicker, better-supported inclined surface inside the keyway, achieving optimized distribution of contact stress. In particular, when the cylinder block is made of relatively low-strength aluminum alloy and the gear key is made of high-strength steel, this stress optimization mechanism can effectively prevent the softer aluminum alloy keyway from crushing, wearing, or breaking due to stress concentration, thereby significantly improving the load-bearing capacity and durability of the key connection. At the same time, the gear key base and the inner hole keyway of the fixed gear adopt a standard rectangular fit, ensuring the stability and ease of installation, and highlighting the optimization focus on the cylinder block side. Furthermore, this gear key structure can utilize its axial dimension to cooperate with components such as springs, adjusting screws, and spring seats, potentially undertaking secondary functions such as assisting axial positioning or transmitting axial preload, further optimizing the structural or functional integration.

[0012] In summary, this utility model innovatively designs the geometry of the interface between the gear key and the cylinder block keyway, and adopts a structure that adapts the inclined side to the inclined sidewall. This changes the contact stress distribution pattern during torque transmission, effectively avoiding stress concentration on the fragile keyway edges. Especially when the cylinder block material is relatively soft, it significantly improves the reliability and durability of the fixed gear connection, and solves the technical problem in the prior art where keyway damage easily leads to compressor performance degradation or failure. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of a swivel-type compressor according to one embodiment of the present invention.

[0014] Figure 2 This is a partial schematic diagram showing the fit between the gear key and the cylinder block keyway and inner hole keyway in one embodiment of the present invention.

[0015] Figure 3 This is a comparison diagram showing the effect of a gear key according to an embodiment of the present invention and a gear key in the prior art. Detailed Implementation

[0016] The embodiments of this utility model will now be described in detail with reference to the accompanying drawings. It should be understood that the embodiments described herein are for illustration and explanation only, and are not intended to limit the scope of protection of this utility model.

[0017] Reference Figures 1 to 3This invention provides a rotary compressor. The compressor includes: a cylinder block 11 with a cylinder block keyway 5; a fixed gear 16 disposed within the cylinder block 11, the inner wall of the central hole of the fixed gear 16 having an inner hole keyway 4; and a gear key 17, including a base embedded in the inner hole keyway 4 and a head embedded in the cylinder block keyway 5. The gear key 17 connects the fixed gear 16 to the cylinder block 11 through the base and the head to prevent relative rotation. The key innovation of this invention lies in that the cross-sectional profile of the cylinder block keyway 5 is designed to include at least one sidewall radially inclined relative to the fixed gear 16. Correspondingly, the head of the gear key 17 has an inclined side surface adapted to the inclined sidewall of the cylinder block keyway 5. This structural design allows the inclined side surface of the gear key 17 head to preferentially and primarily contact the inclined sidewall inside the cylinder block keyway 5 when the compressor is running and the fixed gear 16 is subjected to torque. This contact method alters the stress transmission path, effectively guiding the contact stress from the open edges where stress concentration is prone to occur in traditional rectangular keyway structures to the thicker, more support-friendly inclined bearing surface inside the keyway. This optimizes the contact stress distribution and avoids potential damage to the keyway caused by stress concentration.

[0018] In a preferred embodiment, to ensure stable installation of the gear key 17 within the fixed gear 16 and to simplify manufacturing, the base of the gear key 17 can employ a conventional design, for example, having a generally rectangular cross-section. Correspondingly, the inner keyway 4 of the fixed gear 16 is also designed as a rectangular slot adapted to the rectangular cross-section of the base. During assembly, the base is inserted into the rectangular slot, forming a reliable fit. The head of the gear key 17 extends from the base in a direction away from the fixed gear 16 (typically axially) and is inserted into the cylinder block keyway 5, which has specially inclined sidewalls. This design focuses structural optimization on the cylinder block side interface, which bears the main stresses, while the fixed gear side employs a mature standard structure.

[0019] In many practical applications of oscillating compressors, for reasons of lightweighting and cost, the cylinder block 11 is typically made of relatively low-strength materials such as aluminum alloy. However, to ensure sufficient strength and wear resistance, the gear key 17 and the fixed gear 16 bearing the meshing force are typically made of high-strength steel. In a preferred embodiment of this invention, the cylinder block 11 is made of aluminum alloy, while the gear key 17 is made of high-strength steel. With this common material combination, the cylinder block keyway 5 is formed in the relatively soft aluminum alloy material. When the head of the high-strength steel gear key 17 is embedded in the aluminum alloy cylinder block keyway 5 to transmit torque, if a conventional structure is used, stress concentration can easily lead to damage to the aluminum alloy keyway. This invention, through the aforementioned cooperation of the inclined sidewall and inclined side surface, effectively disperses the contact stress, greatly reducing the risk of crushing, wear, or breakage of the softer aluminum alloy cylinder block keyway 5, and significantly improving the reliability and durability of the connection structure.

[0020] To better understand the working environment of this utility model, in a preferred embodiment, the oscillating compressor further includes a planetary disk component. The planetary disk component 14 (see...) Figure 1 Driven by the compressor main shaft, the planetary disk assembly 14 oscillates, and is equipped with an oscillating gear. During its movement, the oscillating gear meshes with the external teeth of the fixed gear 16. This meshing generates a reaction torque that causes the fixed gear 16 to rotate. The fixed gear 16 resists this rotational tendency by means of the aforementioned optimized connection with the cylinder block 11 via the gear key 17 (including the fit between the base and the inner bore keyway 4 and the optimized fit between the head and the cylinder block keyway 5), thereby maintaining its fixed position relative to the cylinder block 11 and ensuring the normal operation of the compressor. The planetary disk assembly 14 has a steel ball 15 at its center; these are common configurations in the art.

[0021] Furthermore, in one possible implementation, such as Figure 1As shown, the oscillating compressor also includes components for axial preload or positioning, such as an adjusting screw 19, a spring 18, and a spring seat 10 disposed between the adjusting screw 19 and the spring 18. These components are typically arranged axially along the compressor. The adjusting screw 19 can be rotated to adjust its axial position, thereby acting on the spring seat 10 and changing the compression of the spring 18 to apply or adjust the preload force on the relevant components. In this configuration, the gear key 17 is designed to have a certain axial length, located away from the end (i.e., the rear end face) of the fixed gear 16, and axially adjacent to the spring seat 10 or the other end of the spring 18. This spatial arrangement suggests that the gear key 17, in addition to its primary anti-rotation function, also participates in the axial force transmission path, or that its rear end face can serve as a reference surface for axial positioning, thus undertaking auxiliary axial positioning or force transmission functions.

[0022] Specifically, in this embodiment, refer to Figure 1 This image shows a partial cross-sectional view of a rotary compressor. The compressor mainly includes a cylinder block 11, typically made of aluminum alloy, which serves as the primary structural support. A fixed gear 16, usually made of high-strength steel (such as 65Mn or 20CrMn), is housed inside the cylinder block 11 and needs to remain stationary relative to the cylinder block 11. An inner keyway 4, which in this embodiment is a standard rectangular groove, is formed on the inner wall of the central bore of the fixed gear 16. A cylinder block keyway 5 is also formed on the cylinder block 11 at the position corresponding to the inner keyway 4. The key component connecting the fixed gear 16 and the cylinder block 11 is a gear key 17, which is also typically made of high-strength steel. (See reference...) Figure 2 , Figure 2This is a partial schematic diagram showing the fit between the gear key and the cylinder block keyway and inner bore keyway. The Roman numeral II represents an enlarged partial view including the gear key 17. As shown, the gear key 17 has a base and a head. The base has a rectangular cross-section adapted to fit the inner bore keyway 4, for embedding within it. The head extends from the base and is embedded in the cylinder block keyway 5 of the cylinder block 11. A key feature of this embodiment is the fit shape between the cylinder block keyway 5 and the head of the gear key 17. The cross-sectional profile of the cylinder block keyway 5 is not a simple rectangle, but has at least one inclined sidewall. Correspondingly, the cross-section of the head of the gear key 17 also has an inclined sidewall adapted to it. This special geometric fit is the core of this invention. When the compressor is running, the oscillating gear on the planetary disk component driven by the main shaft swashplate assembly meshes with the fixed gear 16, generating a torque that attempts to rotate the fixed gear 16. This torque is transmitted to the gear key 17 through the fixed gear 16, and then to the cylinder block 11 through the gear key 17. Because there is a clearance between the head of gear key 17 and the keyway 5 in the cylinder block, gear key 17 will tilt slightly under stress. At this time, thanks to the design of the tilted side and tilted sidewall, the contact force will preferentially act on the tilted bearing surface inside the keyway 5 in the cylinder block, rather than being concentrated on the weaker edge of the keyway opening as in traditional rectangular keys (see reference...). Figure 3 (Illustrative comparison). This optimized stress distribution is particularly important for the cylinder block 11, which is made of a softer aluminum alloy. It effectively prevents crushing, wear, or breakage of the keyway 5 edges, reducing the generation of metal debris. This ensures that the fixed gear 16 is reliably fixed within the cylinder block 11 for a long period, avoiding problems such as gear skipping caused by key connection failure, and significantly improving the overall reliability and durability of the compressor. Furthermore, as... Figure 1 As shown, the compressor also includes an adjusting screw 19 and a spring 18, as well as a spring seat 10, which together form an axial adjustment / preload mechanism. The rear end face of the gear key 17 is axially adjacent to the spring seat 10, indicating that the gear key 17, in addition to its anti-rotation function, also participates in the transmission or positioning of axial forces.

[0023] Based on this, please refer to Figure 3 , Figure 3 The structural relationship between the prior art gear key (rectangular as shown in the figure) and the gear key 17 of this embodiment and the cylinder block keyway 5 inner hole keyway 4 after assembly is listed and illustrated side by side. It can be seen that the contact point 8 between the prior art gear key and the cylinder block keyway or inner hole keyway is in the middle of the gear key, while the contact point 7 of this embodiment is at the innermost side of the cylinder block keyway 5.

[0024] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this utility model shall still fall within the protection scope of this utility model.

Claims

1. A swing plate compressor characterized by, Comprise: a cylinder block (11) having a cylinder block keyway (5) formed therein; a fixed gear (16) disposed within the cylinder block (11), the fixed gear (16) having an inner hole keyway (4) formed in the inner hole wall of the center hole of the fixed gear (16); a gear key (17) having a base portion embedded in the inner hole keyway (4) and a head portion embedded in the cylinder block keyway (5), the gear key (17) connecting the fixed gear (16) and the cylinder block (11) through the base portion and the head portion to prevent relative rotation; wherein the cross-sectional profile of the cylinder block keyway (5) comprises at least one radially inclined side wall relative to the fixed gear (16); and the head portion of the gear key (17) has an inclined side surface that matches the inclined side wall of the cylinder block keyway (5), so that when torque is applied, the inclined side surface of the head portion mainly contacts the inclined side wall of the cylinder block keyway (5).

2. The swing plate compressor as set forth in claim 1, wherein The base portion of the gear key (17) has a substantially rectangular cross-section, and the inner hole keyway (4) of the fixed gear (16) is a rectangular notch that matches the rectangular cross-section of the base portion, the base portion is embedded in the rectangular notch, and the head portion of the gear key (17) extends from the base portion in a direction away from the fixed gear (16) and is embedded in the cylinder block keyway (5).

3. The swing plate compressor as set forth in claim 2, wherein The cylinder block (11) is made of an aluminum alloy material, and the gear key (17) is made of a high-strength steel material; the cylinder block keyway (5) is formed in the aluminum alloy cylinder block (11), and the steel head portion of the gear key (17) is embedded in the aluminum alloy cylinder block keyway (5).

4. The swing plate compressor as set forth in claim 3, wherein Further comprising a planetary disc component having a swing gear arranged to mesh with the external teeth of the fixed gear (16); the connection of the fixed gear (16) to the cylinder block (11) through the gear key (17) resists the tendency of the fixed gear (16) to rotate caused by the meshing of the swing gear and the fixed gear (16).

5. The swing plate compressor as set forth in claim 4, wherein Further comprising an adjusting screw (19), a spring (18), and a spring seat (10) disposed between the adjusting screw (19) and the spring (18); the adjusting screw (19), the spring seat (10), and the spring (18) are arranged in an axial direction, and the adjusting screw (19) is adjacent to the spring seat (10); the gear key (17) has an axial length, and the end portion thereof away from the fixed gear (16) is axially adjacent to the other end of the spring seat (10) or the spring (18).

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