Main shaft assembly for scroll compressor and compressor

Abstract

This invention provides a spindle assembly for a scroll compressor and a compressor. The spindle assembly includes a spindle, a balance block, and a swing sleeve. Only a connecting portion is provided at the top of the spindle. The balance block includes an integrally formed spindle mating portion, a balancing portion, an eccentric cylindrical portion, and a stop rib portion. The spindle mating portion and the eccentric cylindrical portion are located on opposite sides of the balance block, and the balance block is connected to the spindle via the connecting portion of the spindle mating portion. The swing sleeve is a ring structure with an inner hole that is not concentric with the outer circle. It is fitted onto the eccentric cylindrical portion of the balance block with a clearance fit. The swing sleeve can rotate around the eccentric cylindrical portion, and the stop rib portion is used to limit the retraction angle of the swing sleeve. This invention integrates the eccentric structure of a traditional spindle onto the balance block, simplifying spindle machining. Through the fixed connection between the balance block and the spindle, it solves the vibration problem caused by the balance block swinging with the swing sleeve during compressor startup or operation with liquid, while also reducing cost and noise.

Description

Technical Field

[0001] This invention relates to the field of refrigeration compressor technology, and more specifically, to a spindle assembly for a scroll compressor and a compressor comprising the spindle assembly. Background Technology

[0002] With the booming development of the new energy vehicle industry, higher demands are being placed on the core component of the vehicle air conditioning system—the electric scroll compressor. Consumers are paying increasing attention to vehicle comfort, which directly requires compressors to have lower vibration and noise levels (NVH performance). Among the many components of the compressor, the mating structure of the main shaft, balance weight, and swing sleeve is one of the key factors affecting its NVH performance.

[0003] In existing technologies, the swing sleeve structure of scroll compressors is typically a non-fixed component. Its original design intent was to reduce the starting load or prevent liquid slugging damage when the compressor encounters harsh operating conditions such as starting difficulties (e.g., high-pressure differential start-up) or liquid-containing operation (liquid refrigerant entering the compression chamber). This is achieved by the swinging of the sleeve, causing the profiles of the moving and stationary scrolls to disengage, thus ensuring normal compressor start-up and operation. However, this movable swing sleeve structure has a significant drawback: during the disengagement process, the compressor balance block connected to or in contact with it swings along with the sleeve. This swinging of the balance block disrupts the original dynamic balance of the rotor-spindle system, causing severe vibration and noise during compressor startup or under specific operating conditions, significantly impacting the user experience.

[0004] Several improvement solutions have been developed to address this issue. For example, the first existing technology employs a double-pin limiting structure, which features an eccentric shaft and a stop pin at the top of the crankshaft. The counterweight is clearance-fitted with the eccentric shaft, and the stop pin is clearance-fitted with the second through hole. While this structure achieves self-alignment and limiting functions, the gap between the counterweight and the eccentric shaft means that undesirable oscillations may still occur during compressor startup or low-speed operation, failing to completely resolve the vibration problem.

[0005] The second existing technology proposes a vibration-damping compressor spindle, which incorporates an elastic annular ring between the spindle and the balance block to absorb axial impact. While this solution provides some vibration damping, it remains essentially a traditional structure, where the balance block is fitted onto the spindle with axial clearance, failing to fundamentally eliminate radial and circumferential oscillations. Furthermore, this solution requires additional machining of annular grooves on the spindle and assembly of the elastic ring, increasing the number of parts and machining steps. The first existing technology's stop pin solution requires separate design and pressing of the stop pin, resulting in numerous parts and complex processes; while the second existing technology necessitates machining additional grooves on the crankshaft for mounting the stop ring.

[0006] Therefore, how to design a spindle fitting structure that can both retain the protective function of the swing sleeve under harsh working conditions and effectively suppress the swing of the balance block caused by it, thereby reducing the overall vibration and noise of the compressor, is a technical problem that urgently needs to be solved by those skilled in the art.

[0007] In view of this, the present invention provides a spindle assembly for a scroll compressor and a compressor. Summary of the Invention

[0008] In view of this, the present invention provides a spindle assembly for a scroll compressor and a compressor to solve the problems of poor vibration level caused by the balance block swinging with the swing sleeve during startup or liquid operation of the scroll compressor in the prior art, as well as the problems of large number of parts, complex processing and high cost in the existing improved solutions.

[0009] This invention provides a spindle assembly for a scroll compressor, comprising: The spindle has only a connecting part at its top end; The balance block includes an integrally formed spindle mating part, a balancing part, an eccentric cylindrical part, and a stop rib part; the spindle mating part and the eccentric cylindrical part are respectively located on both sides of the balance block, and the balance block is connected to the spindle through the spindle mating part and the connecting part of the spindle; The swing sleeve is a ring structure with an inner hole that is not concentric with the outer circle. The swing sleeve is fitted onto the eccentric cylindrical part of the balance block and is clearance-fitted with the eccentric cylindrical part. The swing sleeve can deflect around the eccentric cylindrical part. The stop rib is used to limit the retraction angle of the swing sleeve.

[0010] Preferably, the spindle mating part and the spindle are fixedly connected without fasteners.

[0011] Preferably, the arc surface of the stop rib and the swing sleeve is configured such that when the swing sleeve deflects around the center of the eccentric cylindrical part to a preset angle, the outer diameter of the swing sleeve is tangent to the inner diameter of the stop rib, thereby limiting the maximum retraction angle of the swing sleeve.

[0012] Preferably, the balance block further includes a meat reduction groove, which is disposed on the side of the main shaft mating part away from the eccentric cylindrical part.

[0013] Preferably, the stop rib is a continuous arc-shaped rib; or, the stop rib includes a plurality of stop blocks spaced apart along the arc direction.

[0014] Preferably, the balancing portion of the balance block is located on the side away from the eccentric cylindrical portion.

[0015] Preferably, the swing sleeve is provided with an eccentric hole, and the central axis of the eccentric hole is offset from the central axis of the outer circle of the swing sleeve.

[0016] Preferably, the top end of the spindle is provided with a socket for connecting the balance block, and the spindle mating part of the balance block is interference-fitted with the inner wall of the socket.

[0017] Preferably, the top end of the spindle is provided with a socket hole for connecting the balance block, the socket hole is provided with an internal thread, and the outer periphery of the spindle mating part is provided with an external thread that mates with the internal thread. The balance block is fixed to the spindle by a threaded connection.

[0018] The present invention also provides a compressor including the spindle assembly for a scroll compressor as described above.

[0019] The spindle assembly for a scroll compressor of the present invention, and the top end of the spindle in the compressor, are provided with only a connecting part. Unlike the prior art where the eccentric structure is directly machined onto the spindle, the top end of the spindle of the present invention does not have an eccentric pin or eccentric part, thus simplifying the structure and significantly reducing the machining difficulty. With its ingenious structural design, the present invention simultaneously solves multiple technical problems related to manufacturability, vibration control, lightweighting, noise reduction, and cost control, possessing extremely high practical value and broad application prospects. Attached Figure Description

[0020] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0021] Figure 1 This is a perspective view of the spindle assembly for a scroll compressor in the first embodiment of the present invention.

[0022] Figure 2 This is a schematic diagram of the spindle assembly for a scroll compressor in the first embodiment of the present invention.

[0023] Figure 3 This is a top view of the spindle assembly for a scroll compressor in the first embodiment of the present invention.

[0024] Figure 4 This is a schematic diagram of the balance block of the spindle assembly for a scroll compressor in the first embodiment of the present invention.

[0025] Figure 5 This is a top view of the balance block of the spindle assembly for a scroll compressor in the first embodiment of the present invention.

[0026] Figure 6 This is a schematic diagram of the spindle assembly for a scroll compressor in the second embodiment of the present invention.

[0027] Figure Labels

[0028] 1. Spindle

[0029] 11 sockets

[0030] 12 Internal Thread

[0031] 2. Balance blocks

[0032] 21 Spindle mating parts

[0033] 22 Balancing section

[0034] 23. Eccentric cylindrical part

[0035] 24 Stop rib

[0036] 25 Meat Reduction Tank

[0037] 26 External thread

[0038] 3. Set

[0039] 31 Eccentric Hole Detailed Implementation

[0040] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that the invention will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore repeated descriptions of them will be omitted.

[0041] The use of terms such as "first," "second," and similar terms in the specific description does not indicate any order, quantity, or importance, but is merely used to distinguish different components. Furthermore, in the description of this invention, terms such as "upper," "lower," etc., indicate orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings. These are merely for ease of 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 the invention.

[0042] It should be noted that, unless otherwise specified, the embodiments of the present invention and the features in different embodiments can be combined with each other.

[0043] Figure 1 This is a perspective view of the spindle assembly for a scroll compressor in the first embodiment of the present invention. Figure 2This is a schematic diagram of the spindle assembly for a scroll compressor in the first embodiment of the present invention. Figure 3 This is a top view of the spindle assembly for a scroll compressor in the first embodiment of the present invention. Figure 4 This is a schematic diagram of the balance block of the spindle assembly for a scroll compressor in the first embodiment of the present invention. Figure 5 This is a top view of the balance block of the main shaft assembly for a scroll compressor in the first embodiment of the present invention. Figures 1 to 5 As shown, this embodiment provides a spindle assembly for a scroll compressor, the core structure of which includes a spindle 1, a balance block 2, and a swing sleeve 3.

[0044] Specifically, please refer to Figures 1 to 3 The top end of the spindle 1 has only one connecting part, which is preferably a socket hole 11 in this embodiment. No eccentric structure, such as an eccentric pin or eccentric journal, is provided on the spindle 1, which makes the shape of the spindle 1 simple and can be completed using conventional shaft machining processes, significantly reducing the machining difficulty and cost.

[0045] Balance block 2 is a complex part integrally formed using processes such as casting or powder metallurgy. Please refer to... Figure 3 and Figure 4 The balance block 2 specifically includes a main shaft mating part 21, a balancing part 22, an eccentric cylindrical part 23, and a stop rib part 24. Structurally, the main shaft mating part 21 and the eccentric cylindrical part 23 are located approximately on both sides of the balance block 2. The main shaft mating part 21 is used to mate with and fix the connecting part (sleeve hole 11) at the top of the main shaft 1. The eccentric cylindrical part 23 is an offset cylindrical boss with a preset eccentricity between its axis and the rotation center of the main shaft 1. This eccentricity determines the revolution radius of the moving scroll during compressor operation. The balancing part 22 is the part on the balance block 2 used to generate counterweight mass; its shape and size are designed according to the overall mechanical balancing requirements. The stop rib part 24 is an arc-shaped structure protruding from the body of the balance block 2, and its function is to limit the excessive oscillation of the swing sleeve 3.

[0046] The swivel sleeve 3 is a part with a greatly simplified structure. For example... Figure 1 , 3As shown in Figure 5, the swing sleeve 3 is a ring structure with an inner hole that is not concentric with its outer circle. In other words, the center of the outer circle of the swing sleeve 3 does not coincide with the center of its inner hole (i.e., the eccentric hole 31), and there is a designed eccentricity between them. The swing sleeve 3 is fitted onto the eccentric cylindrical part 23 of the balance block 2 with a clearance fit. This means that the inner diameter of the swing sleeve 3 is slightly larger than the outer diameter of the eccentric cylindrical part 23, allowing the swing sleeve 3 to smoothly deflect or rotate freely around the axis of the eccentric cylindrical part 23. When the compressor encounters severe operating conditions such as liquid accumulation or difficulty in starting, this deflection capability of the swing sleeve 3 allows the moving scroll to produce a slight "yield" or "alignment" movement relative to the stationary scroll, thereby protecting the compressor scroll from liquid slugging damage and reducing starting torque. The stop rib 24 blocks the swing sleeve 3 when it deflects to its limit position, preventing excessive deflection that could cause interference or disengagement with other parts.

[0047] This embodiment simplifies the manufacturing process of the main shaft 1 by integrating the eccentric structure onto the balance block 2; it also simplifies the swing sleeve 3 into an independent ring, making its function singular; and the fixed connection between the balance block 2 and the main shaft 1 ensures that the balance block 2 always rotates stably with the main shaft 1 under various operating conditions of the compressor, providing constant dynamic balance compensation and fundamentally avoiding the problem of increased vibration caused by the swing of the balance block. At the same time, the integrated stop rib 24 effectively controls the range of motion of the swing sleeve 3, ensuring the safe operation of the compressor.

[0048] In a preferred embodiment, the socket 11 at the top of the spindle 1 and the spindle mating part 21 of the counterweight 2 are fitted with an interference fit (or press-fit). During assembly, the spindle mating part 21 of the counterweight 2 is pressed into the socket 11 of the spindle 1 using a press-fitting machine. The elastic deformation of the material itself generates a large bonding force, achieving a secure connection between the two. This connection method does not require any additional fasteners such as screws, bolts, pins, or retaining rings. In another variation not shown, the two can also be fixedly connected using methods such as bonding or welding, which also do not require separate fasteners.

[0049] This embodiment further reduces the total number of parts in the spindle assembly by employing fastener-free connection methods such as interference fits, simplifying the bill of materials and inventory management. Simultaneously, it avoids secondary machining such as drilling and tapping on the spindle 1 or balance block 2, reducing processing costs and eliminating stress concentration and structural strength weakening issues that might result from machining threaded holes or pin holes. Furthermore, the fastener-free connection method makes the assembly process simpler and faster, suitable for mass automated production, improving production efficiency and reducing assembly costs.

[0050] In a preferred embodiment, the stop rib 24 on the balance block 2 has an inner arc surface. This inner arc surface and the outer cylindrical surface of the swing sleeve 3 are geometrically configured to have a special "tangential limiting" relationship. Specifically, when the scroll compressor is in normal operating condition, the swing sleeve 3 is in a stable position under the action of centrifugal force and gas force. At this time, a small gap is maintained between the outer cylindrical surface of the swing sleeve 3 and the inner arc surface of the stop rib 24, and the two do not contact each other. When the compressor enters abnormal operating conditions such as liquid-containing operation or difficulty in starting, the swing sleeve 3 will deflect around the center of the eccentric cylindrical part 23. This deflection causes the outer cylindrical surface of the swing sleeve 3 to gradually approach the inner arc surface of the stop rib 24. When the deflection angle of the swing sleeve 3 reaches the maximum value allowed by the design (preset angle), the outer cylindrical surface of the swing sleeve 3 is exactly tangent to the inner arc surface of the stop rib 24. Due to the geometric tangential relationship, the swing sleeve 3 cannot continue to deflect in the same direction, thus its maximum retraction angle is precisely limited.

[0051] In this embodiment, the limiting surface of the stop rib 24 is designed as an arc surface tangent to the outer circle of the swing sleeve 3. When the two contact and limit each other, the contact method is surface contact. Compared with the point contact or line contact commonly seen in the prior art (such as the contact between a cylindrical pin and a planar groove wall), surface contact can distribute the impact force more evenly over a larger area, significantly reducing contact stress. This brings several benefits: First, it reduces local wear on the stop rib 24 and the swing sleeve 3 during impact, improving the service life of the parts; second, surface contact provides greater damping and a smoother stopping effect, absorbing impact energy more effectively than point contact, thereby reducing the metal knocking noise caused by impact; finally, this smooth limiting method also avoids the risk of part breakage due to stress concentration, improving the reliability and durability of the overall structure.

[0052] In a preferred embodiment, the balance block 2 further includes a material removal groove 25. This groove 25 is specifically disposed on the spindle mating portion 21 and located on the side opposite to the eccentric cylindrical portion 23. The groove 25 can be one or more recesses, an annular groove, or a through hole, as long as its function is to remove a portion of the material from the balance block 2.

[0053] When designing the balance block 2, a basic shape and mass distribution that meets the dynamic balance requirements are first calculated based on theoretical calculations. Then, to further achieve compressor weight reduction, or to fine-tune the center of mass position of the counterweight to achieve a more precise dynamic balance effect, one or more reduction grooves 25 can be opened in non-critical stress areas (such as the back side of the main shaft mating part 21) without affecting structural strength and function. By changing the depth, area, and position of the reduction grooves 25, the total mass of the balance block 2 and its center of mass coordinates can be precisely adjusted.

[0054] This embodiment achieves meticulous refinement of the balance block 2 by incorporating a material reduction groove 25. Firstly, the most direct effect of the material reduction groove 25 is to reduce the weight of the balance block 2 itself. When the compressor rotates at high speed, the reduced weight of the balance block 2 directly reduces the rotational inertia of the main shaft 1 and the load on the support bearings, which is beneficial for improving the compressor's mechanical efficiency and dynamic response performance. Secondly, the material reduction groove 25 provides a more flexible adjustment method for the dynamic balance design of the balance block 2. Without changing the overall dimensions of the parts, the imbalance can be precisely adjusted through internal material removal, resulting in higher dynamic balance accuracy in the final product. Finally, the reduced weight of the balance block 2 also helps to reduce the overall weight of the entire compressor, aligning with the lightweight development trend in the automotive industry.

[0055] In a preferred embodiment, depending on different design requirements and manufacturing processes, the stop rib 24 can be implemented in the following two main ways.

[0056] In the first implementation, the stop rib 24 is a continuous arc-shaped rib. For example... Figures 3 to 5 As shown, the arc-shaped rib protrudes from the body of the balance block 2, and its inner arc surface completely surrounds the eccentric cylindrical part 23, forming an arc-shaped fence. This continuous structure has the highest overall stiffness and strength, can withstand large impact loads, and is relatively simple to manufacture, for example, it can be directly formed by mold.

[0057] In the second implementation, the stop rib 24 is not a continuous solid, but rather comprises multiple independent stop blocks spaced apart along the arc direction. For example, two, three, or more separate bosses can be set on the designed arc trajectory. The sides of these stop blocks facing the swing sleeve 3 together form a virtual arc surface, which can also achieve the function of tangentially limiting the swing sleeve 3 to its outer circle when it reaches the maximum retraction angle.

[0058] This embodiment provides several optional structures for the stop rib 24. A continuous arc-shaped rib offers a simple structure, high strength, and strong impact resistance, making it suitable for most common applications. Alternatively, using multiple spaced-apart stop blocks can further reduce the material usage of the balance block 2, achieving greater weight reduction. Furthermore, under certain precision casting or machining processes, discrete stop blocks may be easier to manufacture than continuous long ribs, and their dimensional accuracy is easier to guarantee. In addition, the spaced design provides more possibilities for utilizing the internal space of the balance block 2, such as serving as channels for chip removal or lubrication. Designers can flexibly choose the most suitable structural form based on specific performance, weight, and cost objectives.

[0059] In a preferred embodiment, the balancing portion 22 of the balance block 2 is located on the side away from the eccentric cylindrical portion 23. Please refer to... Figure 2 or Figure 4 As can be clearly seen, during operation, the main eccentric mass of the entire spindle assembly comes from the eccentric cylindrical portion 23 itself and the swing sleeve 3 fitted onto it. To balance the centrifugal force generated by this eccentric mass, the balancing portion 22 of the balance block 2 needs to be positioned on the opposite side of the rotation center of the spindle 1. That is, the balancing portion 22 and the eccentric cylindrical portion 23 are distributed at an angle of approximately 180 degrees along the rotation axis of the spindle. The shape of the balancing portion 22 is usually designed as a fan shape, crescent shape, or irregular shape, with its center of mass as far away from the rotation center as possible, so as to generate a large balancing torque with a small mass. In this embodiment, by placing the balancing portion 22 in the most favorable position for balance, that is, on the side away from the eccentric cylindrical portion 23, a "small effort, large result" balancing effect is achieved. This layout allows the balance block 2 to counteract the largest imbalance with the smallest added mass, which is one of the optimal layouts in rotor dynamics design. Its direct effects are: on the one hand, it further reduces the overall weight of the counterweight 2; on the other hand, it also reduces the increase in radial dimension caused by the increase in counterweight, making the structure of the entire spindle assembly more compact, which is conducive to the miniaturization design of the compressor.

[0060] In a preferred embodiment, the swing sleeve 3 is provided with an eccentric hole 31. This eccentric hole 31 is not located at the exact center of the swing sleeve 3; its central axis deviates from the central axis of the outer circle of the swing sleeve 3 by a designed value. The swing sleeve 3 is fitted onto the eccentric cylindrical portion 23 of the balance block 2 through this eccentric hole 31. When the main shaft 1 drives the balance block 2 to rotate, the axis of the eccentric cylindrical portion 23 on the balance block 2 revolves around the axis of the main shaft 1. Since the swing sleeve 3 and the eccentric cylindrical portion 23 are in clearance fit, and the outer circle of the swing sleeve 3 is used to drive the moving scroll, the eccentricity between the eccentric hole 31 and the outer circle of the swing sleeve 3, and the eccentricity of the eccentric cylindrical portion 23, work together to ultimately determine the actual revolution radius of the moving scroll relative to the rotation center of the main shaft 1. By precisely selecting the matching relationship between these two eccentricities, the required compressor displacement can be achieved.

[0061] This embodiment clarifies the eccentric structural features of the pendulum sleeve 3. The eccentric function is integrated into the pendulum sleeve 3 through an eccentric hole 31, making the pendulum sleeve 3 a pure, single-function "self-aligning ring." This design results in a regular geometric shape for the pendulum sleeve 3 (its basic shape is a circular ring), greatly simplifying its manufacturing process. It can be produced using high-precision thin-walled tubing or precision casting and powder metallurgy processes, which helps ensure consistency during mass production and reduces the cost of individual parts.

[0062] In a preferred embodiment, the top end of the spindle 1 is provided with a socket 11 for connecting the balance block 2. The socket 11 is a blind hole or through hole opened along the axial direction of the spindle 1, and its inner wall is a smooth cylindrical surface.

[0063] Accordingly, the main shaft mating part 21 of the balance block 2 is designed as a cylindrical journal that matches the socket 11. The outer diameter of this journal is slightly larger than the inner diameter of the socket 11 during machining, according to design requirements. During assembly, a cold pressing or hot pressing process is used to force the main shaft mating part 21 of the balance block 2 into the socket 11 of the main shaft 1. Due to the interference fit, the wall of the socket 11 undergoes elastic deformation, thereby applying a huge radial pressure to the main shaft mating part 21. This pressure is sufficient to transmit the torque and axial force required for compressor operation.

[0064] The interference fit connection scheme provided in this embodiment is a very mature and efficient mechanical connection technology. Its significant technical advantages include: First, extremely high connection reliability, with no additional connecting parts and no risk of loosening, making it ideal for high-speed rotating machinery such as compressors. Second, simple structure; neither the spindle 1 nor the balance block 2 requires machining of threads, keyways, or pin holes, greatly reducing manufacturing costs. Third, the assembly process can be automated, resulting in high production efficiency. Fourth, due to the keyless connection, stress concentration caused by keyways on the spindle is avoided, improving the fatigue strength of the spindle 1.

[0065] In a preferred embodiment, please refer to Figure 6 The diagram illustrates a second embodiment of the invention, namely a threaded connection scheme. Similar to the first embodiment, a socket hole 11 is also provided at the top end of the spindle 1. Unlike the first embodiment, the inner wall of the socket hole 11 is machined with an internal thread 12.

[0066] Accordingly, the outer periphery of the spindle mating part 21 of the balance block 2 is machined with an external thread 26 that mates with the internal thread 12. During assembly, the balance block 2 is screwed into the sleeve hole 11 of the spindle 1, and the tight connection between the two is ensured by controlling the tightening torque. To further prevent the threaded connection from loosening under frequent start-stop and vibration impact of the compressor, thread-locking adhesive can be applied to the threads, or an anti-loosening washer can be added between the end faces of the balance block 2 and the spindle 1.

[0067] The threaded connection solution provided in this embodiment is a detachable fixed connection method. Compared with the interference fit in Embodiment 8, the main advantage of the threaded connection is its detachability. In the event of compressor maintenance or rework, the balance block 2 can be easily removed from the main shaft 1, facilitating part replacement or individual testing. Furthermore, the tightening force of the threaded connection can be precisely controlled using a torque wrench, resulting in better connection consistency. Although thread machining increases costs slightly, this solution offers greater flexibility for certain applications or product lines requiring detachability.

[0068] This invention also provides a compressor, particularly an automotive electric scroll compressor. The core feature of this compressor is that it internally includes a main shaft assembly for a scroll compressor as described above. In addition to the main shaft assembly defined in this invention, the compressor also includes conventional components such as a housing, a stationary scroll, a moving scroll, a motor stator, a motor rotor, a main bearing, a rear cover, and a controller. The main shaft 1 is rotatably supported within the housing by the main bearing. One end of the main shaft 1 is connected to the motor rotor to receive rotational driving force. The main shaft assembly of this invention (including a counterweight 2 and a swing sleeve 3) is located at the top of the main shaft 1, and the swing sleeve 3 is connected to the moving scroll. When the main shaft 1 rotates, the eccentric cylindrical portion 23 of the counterweight 2 and the eccentric hole 31 of the swing sleeve 3 drive the moving scroll to revolve relative to the stationary scroll, thereby compressing the refrigerant.

[0069] The compressor in this embodiment exhibits significantly improved performance across the entire operating range due to the adoption of the low-vibration spindle assembly of the present invention. Particularly during startup, liquid-loaded operation, or high-load operation, the compressor operates smoothly and reliably, with a significantly reduced vibration acceleration level and noticeably less harsh noise. Furthermore, the reduced number of parts and simplified manufacturing process make the compressor more cost-effective. Therefore, this embodiment provides a scroll compressor that combines high performance, high reliability, low NVH, lightweight design, and low cost, making it particularly suitable for air conditioning systems in new energy vehicles with extremely high requirements for comfort and driving range.

[0070] The specific embodiments of the present invention are as follows: In this preferred embodiment, a low-vibration scroll compressor for an air conditioning system in a new energy vehicle is provided. This compressor includes an optimized spindle assembly. Specifically, the spindle assembly consists of three main metal parts: a spindle 1, a counterweight 2, and a swing sleeve 3. All parts are preferably made of high-strength, wear-resistant alloy steel, such as 20CrMnTi or 40Cr, and are manufactured through precision machining and heat treatment processes.

[0071] Structure and Manufacturing of Spindle 1: Spindle 1 is a slender stepped shaft, with one end connected to the rotor of the motor and the other end (top) being a free end. In this design, the top of spindle 1 has only a single cylindrical socket 11 with high machining precision. Apart from the necessary bearing seats and oil grooves, the overall outer circumference of spindle 1 lacks the complex eccentric bosses or eccentric pin holes found in traditional designs. This simplified design allows spindle 1 to be mass-produced using a high-precision centerless grinder, significantly improving production efficiency and yield while reducing processing costs.

[0072] Integrated Structure of Balance Block 2: As a key functional integrated component, Balance Block 2 has a complex shape. It is recommended to use powder metallurgy for one-piece molding to ensure dimensional accuracy and internal material density. Balance Block 2 comprises the following five functional parts, which form an inseparable whole: Spindle mating part 21: Located at the bottom center of the balance block 2, it is a high-precision cylinder. Its outer diameter is designed to form an interference fit with the sleeve hole 11 at the top of the spindle 1. The specific interference amount is determined based on the torque transmission calculation, and is usually selected between 0.01mm and 0.05mm to ensure the reliability of the connection.

[0073] Eccentric cylindrical portion 23: Located at the top of the balance block 2, and offset from the axis of the main shaft mating portion 21 by a predetermined distance L1. The outer surface of this cylinder needs to be precision ground to ensure the mating clearance with the swing sleeve 3. To facilitate installation and the formation of a lubricating oil film, its surface can be machined with tiny oil grooves or textures.

[0074] Balancing section 22: A fan-shaped or arc-shaped protrusion extending to one side from the main body of the balancing block 2. Its shape, thickness, and angle have been precisely calculated and experimentally verified to balance the centrifugal force system generated by the eccentric cylindrical section 23, the pendulum sleeve 3, and the connected moving vortex disk. Its center of mass is located on the side of the rotation axis of the main shaft 1 away from the eccentric cylindrical section 23.

[0075] Stop rib 24: A continuous arc-shaped raised rib is provided around the root of the eccentric cylindrical part 23. The radius R1 of its inner arc surface is slightly larger than the outer radius R2 of the swing sleeve 3. The center of this inner arc surface coincides with the center of the eccentric cylindrical part 23, and its arc angle range is determined according to the maximum retraction angle α required by the swing sleeve 3. When the deflection angle of the swing sleeve 3 reaches α, the outer circle of the swing sleeve 3 is exactly tangent to the inner arc surface of the stop rib 24.

[0076] Material reduction groove 25: One or more annular or fan-shaped recesses are provided on the back side of the main shaft mating part 21 (i.e., the side opposite to the eccentric cylindrical part 23). The presence of these recesses removes excess material that does not affect the structural strength, thereby reducing the total mass of the balance block 2 by about 5%-10%, and also facilitates stress release and dimensional stability during the sintering process of powder metallurgy parts.

[0077] Simplified Structure of Swing Sleeve 3: Swing sleeve 3 is an extremely simple annular part. Its outer shape is a cylindrical surface, with an eccentric hole 31 inside. The center of the eccentric hole 31 is offset from the center of the outer circle of swing sleeve 3 by a predetermined distance L2. The sum of L1 and L2 determines the revolution radius of the moving scroll. The inner hole of swing sleeve 3 and the eccentric cylindrical portion 23 of the counterweight 2 are designed with a small clearance fit, for example, a single-sided clearance of 0.01mm-0.03mm, to ensure that swing sleeve 3 can deflect freely and smoothly. The outer circle of swing sleeve 3 has a high surface finish to reduce friction with the moving scroll bearing. Since swing sleeve 3 no longer serves as a counterweight, its overall wall thickness can be designed to be thinner, significantly reducing its weight.

[0078] Assembly process: First, using automated press-fitting equipment, the main shaft mating part 21 of the balance block 2 is precisely pressed into the sleeve hole 11 of the main shaft 1 under constant pressure and displacement control, completing the fixed connection. Then, the swing sleeve 3 is fitted onto the eccentric cylindrical part 23 of the balance block 2 through its eccentric hole 31, forming a clearance fit. Afterward, the entire main shaft assembly is installed into the compressor housing. The outer circle of the swing sleeve 3 is directly or through other transmission structures connected to the moving scroll and drives its movement.

[0079] The specific working process and principles are as follows: When the compressor is operating normally and in good working condition, the main shaft 1 drives the balance block 2 to rotate at high speed. The balancing part 22 fixed on the balance block 2 generates a stable balancing force. Under the combined action of centrifugal force and gas reaction force, the swing sleeve 3 is stably pressed against a specific side of the eccentric cylindrical part 23, driving the moving scroll to perform a zero-slip revolution. At this time, a gap is maintained between the outer circle of the swing sleeve 3 and the stop rib part 24, and they do not contact each other.

[0080] When the compressor draws in liquid refrigerant (operating with liquid) or starts at low temperatures (difficult to start), the incompressible nature of the liquid refrigerant generates a huge liquid slugging force on the moving scroll, attempting to disengage the meshing between the moving and stationary scrolls. This additional force is transmitted to the swing sleeve 3, generating a torque that forces the swing sleeve 3 to deflect around the center of the eccentric cylindrical portion 23. When this torque exceeds the gas torque and centrifugal torque required to maintain the position of the swing sleeve under normal operating conditions, the swing sleeve 3 will deflect in the retracting direction. As the swing sleeve 3 deflects, the profile of the moving scroll partially disengages from the profile of the stationary scroll, forming a pressure relief channel, thereby protecting the scroll from damage. At the same time, due to the deflection of the swing sleeve 3, its contact position with the eccentric cylindrical portion 23 changes, which may cause a brief dynamic balance disturbance. However, since the balance block 2, which undertakes the main dynamic balancing task, is fixedly connected to the main shaft 1, it does not swing with the swing sleeve 3. Therefore, the imbalance of the entire rotor system hardly changes, and the vibration level of the compressor can always be kept within a low range.

[0081] When the adverse operating condition ends and the compressor resumes normal operation, the dynamic force returns to balance, and the swing sleeve 3 automatically returns to its normal operating angle under the action of centrifugal force. Throughout the process, if the deflection of the swing sleeve 3 reaches the maximum allowable angle α, its outer surface will form a smooth surface contact with the inner arc surface of the stop rib 24 on the balance block 2, thus reliably stopping it and preventing other malfunctions that may be caused by excessive deflection. Because the swing sleeve 3 is very lightweight and the limiting mechanism is surface contact, the vibration and noise generated by the impact are minimal.

[0082] Technical Summary: This specific implementation scheme fully embodies the core technical concept of this invention. This scroll compressor successfully resolves the long-standing contradiction between "passability under harsh operating conditions" and "NVH performance under normal operating conditions" in existing technologies. Through creative functional decomposition and re-integration, it achieves simplified spindle machining, lightweight swing sleeve, and fixed balance block, ultimately resulting in excellent comprehensive performance characterized by low manufacturing cost, low operating noise, low vibration level, high start-up reliability, and insensitivity to liquid-laden conditions. This compact spindle assembly structure, with a very small number of parts, makes a significant contribution to the miniaturization and lightweighting of compressors, and is a highly competitive core technology solution for next-generation new energy vehicle air conditioning systems.

[0083] Compared with the prior art, the present invention has the following beneficial effects: Simplified spindle machining and reduced costs: This invention integrates the complex eccentric part or eccentric pin structure on the traditional spindle into the balance block, so that the spindle only needs to be set with a simple connection part (such as a cylindrical surface or connecting hole), which greatly simplifies the structure and significantly reduces the machining difficulty and cost.

[0084] Significantly Improved Vibration Performance: This invention separates the balancing function from the traditional movable swing sleeve and integrates it along with the eccentric structure onto an independent balance block, which is then fixedly connected to the main shaft. This key improvement solves the problem in the prior art where the balance block swings with the swing sleeve during compressor startup or operation with liquid, causing the rotor dynamic balance to be disrupted and the whole machine to vibrate violently. This significantly improves the operating stability of the compressor over a wide range of operating conditions.

[0085] Weight reduction and volume reduction: The material reduction grooves set on the balance block can accurately reduce excess mass while ensuring strength and imbalance requirements, realizing the miniaturization and lightweighting of key compressor components, which meets the urgent need for lightweight components in new energy vehicles.

[0086] Reduced impact noise from the swing sleeve retraction: In this invention, the swing sleeve is simplified into a lightweight circular structure, eliminating the original heavy balancing section and significantly reducing its mass. When the compressor encounters harsh operating conditions that cause the swing sleeve to retract and collide with the stop rib, the reduced mass of the swing sleeve decreases the impact kinetic energy and impact force, thereby effectively reducing impact noise.

[0087] Optimized limiting structure for improved reliability: This invention achieves limiting by tangentially engaging the stop rib integrated on the balance block with the outer circle of the swing sleeve. When the maximum retraction angle is reached, the two are in surface contact, which, compared to point or line contact in existing technologies, results in more uniform force distribution, less impact, reduced localized wear, and improved durability and reliability of the limiting structure.

[0088] Reduced number of parts and assembly steps: This invention integrates the stop structure (stop rib) with the balance block, eliminating the need for separate machining of stop pin holes, installation of stop pins, or separate machining of slots and installation of stop rings, as required by existing technologies. This reduces the types and number of parts, simplifies the assembly process, and lowers material management and manufacturing costs.

[0089] In summary, the spindle assembly and compressor of this invention for a scroll compressor resolve the long-standing contradiction between "accessibility under harsh operating conditions" and "NVH performance under normal operating conditions" in existing technologies. Through innovative functional decomposition and re-integration, it achieves simplified spindle machining, lightweight swing sleeve, and fixed balance block, ultimately resulting in excellent comprehensive performance characterized by low manufacturing cost, low operating noise, low vibration level, high start-up reliability, and insensitivity to liquid-laden conditions. This spindle assembly has a compact structure and a very small number of parts, making a significant contribution to the miniaturization and lightweighting of compressors, and is a highly competitive core technology solution for next-generation new energy vehicle air conditioning systems.

[0090] The above description, in conjunction with specific optional embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. A spindle assembly for a scroll compressor, characterized in that, include: The main shaft (1) has only a connecting part at its top end; The balance block (2) includes an integrally formed main shaft mating part (21), a balancing part (22), an eccentric cylindrical part (23), and a stop rib part (24); the main shaft mating part (21) and the eccentric cylindrical part (23) are respectively located on both sides of the balance block (2), and the balance block (2) is connected to the main shaft (1) through the main shaft mating part (21); The swing sleeve (3) is a ring structure with an inner hole that is not concentric with the outer circle. The swing sleeve (3) is fitted onto the eccentric cylindrical part (23) of the balance block (2) and is in clearance fit with the eccentric cylindrical part (23). The swing sleeve (3) can deflect around the eccentric cylindrical part (23). The stop rib (24) is used to limit the retraction angle of the swing sleeve (3).

2. The spindle assembly for a scroll compressor according to claim 1, characterized in that, The main spindle mating part (21) and the main spindle (1) are fixedly connected without fasteners.

3. The spindle assembly for a scroll compressor according to claim 1, characterized in that, The arc surface of the stop rib (24) and the swing sleeve (3) is configured such that when the swing sleeve (3) deflects around the center of the eccentric cylindrical part (23) to a preset angle, the outer diameter of the swing sleeve (3) is tangent to the inner diameter of the stop rib (24), thereby limiting the maximum retraction angle of the swing sleeve (3).

4. The spindle assembly for a scroll compressor according to claim 1, characterized in that, The balance block (2) also includes a meat reduction groove (25), which is located on the side of the main shaft mating part (21) away from the eccentric cylindrical part (23).

5. The spindle assembly for a scroll compressor according to claim 1, characterized in that, The stop rib (24) is a continuous arc-shaped rib; or, the stop rib (24) includes a plurality of stop blocks spaced apart along the arc direction.

6. The spindle assembly for a scroll compressor according to claim 1, characterized in that, The balancing part (22) of the balance block (2) is located on the side away from the eccentric cylindrical part (23).

7. The spindle assembly for a scroll compressor according to claim 1, characterized in that, The swing sleeve (3) is provided with an eccentric hole (31), and the central axis of the eccentric hole (31) is offset from the central axis of the outer circle of the swing sleeve (3).

8. The spindle assembly for a scroll compressor according to claim 1, characterized in that, The top end of the spindle (1) is provided with a socket (11) for connecting the balance block (2), and the spindle mating part (21) of the balance block (2) is interference-fitted with the inner wall of the socket (11).

9. The spindle assembly for a scroll compressor according to claim 1, characterized in that, The top end of the spindle (1) is provided with a socket (11) for connecting the balance block (2). The socket (11) is provided with an internal thread (12). The outer periphery of the spindle mating part (21) is provided with an external thread (26) that mates with the internal thread (12). The balance block (2) is fixed to the spindle (1) by a threaded connection.

10. A compressor, characterized in that, Includes the spindle assembly for a scroll compressor as described in claim 1.

Images