Single-double-stage adjustable servo motor direct-drive symmetrical scroll compressor

Abstract

A single double-stage adjustable servo motor direct drive symmetric scroll compressor, including double-sided scroll tooth static scroll mechanism and its two sides symmetrically arranged dynamic scroll plate, dynamic scroll plate is placed in double-sided scroll tooth static scroll mechanism and frame, dynamic scroll plate and double-sided scroll tooth static scroll mechanism two sides of scroll are engaged to form a plurality of crescent compression cavity, dynamic scroll plate hub, frame is connected through bearing in the proximal end of motor shaft; The flange plate is arranged between the frame and the motor shell to form a cavity, and a balance block is arranged in the cavity; The motor shaft is provided with an end balance block in the motor end cover; The motor rotor connected on the motor shaft and the motor stator connected on the motor shell constitute a permanent magnet synchronous servo motor; The compressor realizes high efficiency, variable frequency speed regulation and low energy consumption, the double-sided scroll tooth static scroll mechanism can work in parallel type high power one-stage compression or series type high compression ratio two-stage compression mode, and is suitable for more working occasions.

Description

Technical Field

[0001] This invention relates to the field of scroll compressor technology, specifically to a single- or double-stage adjustable servo motor direct-drive symmetrical scroll compressor. Background Technology

[0002] Scroll compressors are a new type of positive displacement fluid machinery, known as the technologically advanced third-generation compressors. Compared to reciprocating, rotary, and screw compressors, they have advantages such as smaller size, fewer parts, higher efficiency, and lower noise. Scroll compressors use an electric motor to drive a scroll plate, converting electrical energy into gas pressure energy to increase gas pressure and transport gases. They are widely used in refrigeration, packaging, machinery, petrochemical, and other fields.

[0003] A scroll compressor contains two scroll plates: a moving scroll plate and a stationary scroll plate. During operation, the helical lines on the moving and stationary scroll plates mesh to form numerous crescent-shaped compression chambers. As the motor drives the eccentric rotation of the moving scroll plate, the crescent-shaped compression chambers continuously move inward from the outside. Simultaneously, the gas within each compression chamber is continuously pushed towards the center. As the volume of the compression chamber decreases, the gas pressure within the chamber continuously increases until it is discharged through the exhaust port of the stationary scroll plate, completing the compression process.

[0004] As scroll compressor technology continues to develop and mature, to meet higher market demands and ensure energy conservation and environmental protection, large displacement, variable frequency speed control, and low energy consumption have become the future development trends for scroll compressors. Currently, large displacement scroll compressors on the market are mainly achieved by increasing the size of the scroll plate, increasing the speed, and connecting multiple units in parallel. These methods inevitably lead to increased overall compressor size, complex structure, and higher failure rates. Furthermore, electric scroll compressors typically use asynchronous motors or DC brushless permanent magnet synchronous motors for drive. Traditional asynchronous motors are inefficient, bulky, and energy-intensive, while DC brushless permanent magnet synchronous motors are unsuitable for high-power applications. Permanent magnet AC servo motors, on the other hand, have advantages such as small size, high performance, and a wide speed range, and are widely used in industrial fields. In addition, improving compressor efficiency and energy consumption levels is mainly achieved through optimizing the compressor's structural design and improving the variable frequency motor. Therefore, developing new scroll compressors that are small in size, simple in structure, high in performance, and low in energy consumption is of great significance.

[0005] In summary, the current scroll compressors on the market have the following shortcomings: (1) If the compressor power is increased, the size will be larger, the structure will be more complex, and the failure rate will be higher; (2) The compressor is only suitable for a limited range of scenarios, and the compression ratio is fixed and cannot be adjusted; (3) The scroll compressor uses an asynchronous motor which is inefficient, large in size and has high energy consumption, and the DC brushless permanent magnet synchronous motor is difficult to use in high-power scenarios; (4) When the scroll plate speed is high, the eccentric spindle will have a large eccentric torque, which will increase wear and shorten the life. Summary of the Invention

[0006] To overcome the shortcomings of the prior art, the present invention aims to provide a single- or dual-stage adjustable servo motor direct-drive symmetrical scroll compressor. By employing the concept of servo motor direct drive and integrated design, two AC servo motors directly drive two moving scrolls to operate the entire compressor. The use of servo motors and the dual-scroll device simplify compressor power adjustment and achieve a high power-to-volume ratio while doubling the maximum power, thereby meeting the requirements of high compressor efficiency, variable frequency speed control, and low energy consumption. In addition, the specially designed dual-sided scroll tooth stationary scroll mechanism allows for selection of the intake and exhaust channels via internal valves, enabling the compressor to operate in either parallel high-power single-stage compression or series high-compression-ratio two-stage compression mode. The dual-mode switching is applicable to a wider range of working conditions.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] A single- or double-stage adjustable servo motor direct-drive symmetrical scroll compressor includes a double-sided scroll tooth stationary scroll mechanism 13 and symmetrically arranged moving scrolls 12 on both sides thereof. The double-sided scroll tooth stationary scroll mechanism 13 is sealed to one end of the frame 9 on both sides. The moving scrolls 12 are positioned between the double-sided scroll tooth stationary scroll mechanism 13 and the frame 9, and are connected to the frame 9 via a cross-slip ring 14. The moving scrolls 12 and the scrolls on both sides of the double-sided scroll tooth stationary scroll mechanism 13 mesh with each other to form multiple crescent-shaped compression chambers. The hub of the moving scroll 12 and the frame 9 are respectively connected by needle rollers. The self-aligning ball bearing 10 is connected to the near end of the motor spindle 6; the other end of the frame 9 is provided with a flange 8 between the middle of one end of the motor housing 3 and the flange 8, and a cavity is formed in the flange 8. The motor spindle 6 is partially installed with a balance block 7 in the cavity; the other end of the motor housing 3 is connected to the motor end cover 1. The motor end cover 1 is provided with a ball bearing 2 to support the far end of the motor spindle 6, and another end balance block 17 with a larger mass is provided in the motor end cover 1; the motor rotor 5 connected to the motor spindle 6 and the motor stator 4 connected to the motor housing 3 constitute a permanent magnet synchronous servo motor.

[0009] An oil spray port is provided on the flange 8 to facilitate lubrication and heat dissipation.

[0010] The self-aligning ball bearing 10 is coaxially mounted on the frame 9 and fixed by the bearing retaining ring 15 and the shaft elastic retaining ring 16.

[0011] The double-sided scroll tooth static scroll mechanism 13 is bolted to the frame 9, the frame 9 to the flange 8, and the flange 8 to the motor housing 3. The bolt holes on the double-sided scroll tooth static scroll mechanism 13, the frame 9, the flange 8, and the motor housing 3 are arranged symmetrically around the circumference to ensure that the central axis of the motor is coaxial with the central axis of the frame.

[0012] The double-sided scroll toothed stationary scroll mechanism 13 includes two scroll surfaces, left and right, as well as internal air intake and exhaust channels, namely, a right scroll L1 and a left scroll L6. The left scroll L6 is provided with a left air intake port L9 and a left air outlet L7. The right scroll L1 includes two independent first air intake channels L3 and second air intake channels L12, as well as a first exhaust channel L11. A valve for adjusting the air intake and exhaust channels is connected between the left air outlet L7 and the first air intake channel L3. The valve is provided with a second exhaust channel L10 at its bottom. The valve includes a valve stem L4 and an upper valve plug L5 and a lower valve plug L8 connected to it.

[0013] When valve stem L4 is downward, lower valve plug L8 blocks the second exhaust passage L10. The compressed gas from the left scroll plate is discharged from the left outlet L7 and then enters the right scroll compressor through the first intake pipe L3 for secondary compression. The compressed gas is discharged from the first exhaust pipe L11. At this time, the compressor is in a series high compression ratio two-stage compression mode. When valve stem L4 is pulled up, upper valve plug L5 blocks the first intake pipe L3. At this time, the gas discharged from the left scroll compressor is directly discharged from the second exhaust passage L10. The right scroll plate intake port cover L13 is opened, and the right scroll device takes in air from the second intake passage L12. The compressed gas is discharged from the first exhaust passage L11. Thus, the left and right scroll compressors work simultaneously to achieve high-power air compression. At this time, the compressor is in a parallel high-power single-stage compression mode.

[0014] The rotor system of the compressor is composed of the internal rotating parts of the single- or double-stage adjustable servo motor direct-drive symmetrical scroll compressor. The compressor main shaft is an eccentric main shaft, which together with the moving scroll plate 12, balance block 7, self-aligning ball bearing 10, needle roller bearing 11, ball bearing 2, and end balance block 17 constitutes the rotor system on one side of the compressor.

[0015] The moving scroll plate 12 includes a first material removal portion D1, a second material removal portion D2 on the chassis, and two grooves for locking the cross slip ring, namely the first cross slip ring groove D3 and the second cross slip ring groove D4. The removal portion and the scroll teeth form a center of mass balance design, so that its center of mass is located on the same axis as the needle roller bearing 11, achieving local static balance. The balance block 7 and the end balance block 17 ensure force balance and torque balance of the main shaft inside the compressor as much as possible, and maximize the static and dynamic balance of the rotor system inside the compressor.

[0016] The vortex head of the vortex disk 12 uses double circular arcs plus straight line correction near the base circle H1 of the vortex line. The inner side H3 of the vortex tooth has an inner circular arc correction starting point H2, and the outer side H4 of the vortex tooth has an outer circular arc correction starting point H5. The middle part between the inner circular arc correction starting point H2 and the outer circular arc correction starting point H5 is double circular arc plus straight line correction.

[0017] The exhaust port of the static vortex disk mechanism 13 with double-sided spiral toothed teeth uses a combination of arc and straight line shapes to increase the exhaust area and reduce gas velocity and gas flow pulsation.

[0018] Compared to existing scroll compressors, the present invention has the following advantages:

[0019] (1) The present invention selects the intake and exhaust channels by adjusting the valve position, thereby enabling the selection of the compressor working mode. It can work in parallel high-power first-stage compression mode or in series high-compression ratio second-stage compression mode, which can adapt to more working scenarios.

[0020] (2) The present invention uses two symmetrically arranged permanent magnet synchronous motors as power sources, which have advantages such as small size, low energy consumption and wide speed range. In addition, the motor spindle is used directly as the power shaft of the compressor, reducing the transmission mechanism and making the compressor structure simpler, with higher working efficiency and more stable operation.

[0021] (3) The eccentric spindle used in this invention ensures the balance of the rotor system to the greatest extent by setting balance blocks and improving the bottom structure of the moving scroll plate, thereby reducing bearing vibration and wear and improving the service life of the compressor.

[0022] (4) The present invention uses double circular arcs plus straight lines to correct the head of the vortex tooth near the base circle, which makes the machining of the vortex tooth easier and improves the strength and rigidity at the tooth head position. The exhaust hole is corrected by a combination of circular arcs and straight lines, which increases the exhaust area, reduces the gas velocity and gas flow pulsation, and makes the compressor working state more stable. Attached Figure Description

[0023] Figure 1 This is an assembly cross-sectional view of the present invention.

[0024] Figure 2 This is a cross-sectional view of the double-sided spiral tooth static spiral disk mechanism of the present invention.

[0025] Figure 3 This is a diagram of the dynamic vortex disk for the balanced center of mass design of this invention.

[0026] Figure 4 This is a schematic diagram of the correction of the vortex line of the moving vortex disk of the present invention.

[0027] Figure 5 This is a schematic diagram of the exhaust port of the double-sided spiral tooth static vortex disk mechanism of the present invention. Detailed Implementation

[0028] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0029] Reference Figure 1A single- or double-stage adjustable servo motor direct-drive symmetrical scroll compressor includes a double-sided scroll tooth stationary scroll mechanism 13 and symmetrically arranged moving scrolls 12 on both sides thereof. The double-sided scroll tooth stationary scroll mechanism 13 is sealed to one end of the frame 9 on both sides. The moving scrolls 12 are positioned between the double-sided scroll tooth stationary scroll mechanism 13 and the frame 9, and are connected to the frame 9 via cross-slip rings 14 to prevent the moving scrolls 12 from rotating. The moving scrolls 12 and the scrolls on both sides of the double-sided scroll tooth stationary scroll mechanism 13 mesh with each other to form multiple crescent-shaped compression chambers. The hub of the moving scrolls 12 and the frame 9 are respectively equipped with needle roller bearings 11. A self-aligning ball bearing 10 is connected to the near end of the motor spindle 6; a flange 8 is provided between the other end of the frame 9 and one end of the motor housing 3, and a cavity is formed in the flange 8. A balance block 7 is installed in part of the cavity of the motor spindle 6. An oil spray port can be opened on the flange 8 for easy lubrication and heat dissipation; the other end of the motor housing 3 is connected to the motor end cover 1. A ball bearing 2 is provided in the motor end cover 1 to support the far end of the motor spindle 6, and another end balance block 17 with a larger mass is provided in the motor end cover 1; the motor rotor 5 connected to the motor spindle 6 and the motor stator 4 connected to the motor housing 3 constitute a permanent magnet synchronous servo motor.

[0030] The self-aligning ball bearing 10 is coaxially mounted on the frame 9 and fixed by the bearing retaining ring 15 and the shaft elastic retaining ring 16.

[0031] The double-sided scroll tooth static scroll mechanism 13 is bolted to the frame 9, the frame 9 to the flange 8, and the flange 8 to the motor housing 3. The bolt holes on the double-sided scroll tooth static scroll mechanism 13, the frame 9, the flange 8, and the motor housing 3 are arranged symmetrically around the circumference to ensure that the central axis of the motor is coaxial with the central axis of the frame. This makes it easy to process and simple to install.

[0032] The motor rotor 5, self-aligning ball bearing 10, balance block 7, needle roller bearing 11, end balance block 17, and ball bearing 2 are all mounted on the motor main shaft 6.

[0033] Reference Figure 2 The dual-sided scroll tooth static scroll mechanism 13 includes two scroll surfaces, left and right, as well as internal air intake and exhaust channels, namely, a right scroll L1 and a left scroll L6. The left scroll L6 is provided with a left air intake port L9 and a left air outlet L7. The right scroll L1 includes two independent first air intake channels L3 and second air intake channels L12, as well as a first exhaust channel L11. A valve for adjusting the air intake and exhaust channels is connected between the left air outlet L7 and the first air intake channel L3. The valve is provided with a second exhaust channel L10 at its bottom. The valve includes a valve stem L4 and an upper valve plug L5 and a lower valve plug L8 connected to it.

[0034] When valve stem L4 is downward, lower valve plug L8 blocks the second exhaust passage L10. The compressed gas from the left scroll plate is discharged from the left outlet L7 and then enters the right scroll compressor through the first intake pipe L3 for secondary compression. The compressed gas is discharged from the first exhaust pipe L11. At this time, the compressor is in a series high compression ratio two-stage compression mode. When valve stem L4 is pulled up, upper valve plug L5 blocks the first intake pipe L3. At this time, the gas discharged from the left scroll compressor is directly discharged from the second exhaust passage L10. The right scroll plate intake port cover L13 is opened, and the right scroll device takes in air from the second intake passage L12. The compressed gas is discharged from the first exhaust passage L11. Thus, the left and right scroll compressors work simultaneously to achieve high-power air compression. At this time, the compressor is in a parallel high-power single-stage compression mode.

[0035] The rotor system of a single- or double-stage adjustable servo motor direct-drive symmetrical scroll compressor consists of internal rotating components. The compressor main shaft is an eccentric shaft, which, together with the moving scroll plate 12, balance block 7, self-aligning ball bearing 10, needle roller bearing 11, ball bearing 2, and end balance block 17, constitutes the rotor system on one side of the compressor. The structure of the moving scroll plate 12 is as follows: Figure 3 As shown, the system includes a first material removal portion D1, a second material removal portion D2 on the chassis, and two grooves for holding the cross-shaped slip ring, namely the first cross-shaped slip ring groove D3 and the second cross-shaped slip ring groove D4. The removal portion and the scroll tooth form a center-of-gravity balance design, so that its center of gravity is located on the same axis as the needle roller bearing 11, achieving local static balance. In addition, the balance block 7 and the end balance block 17 ensure force balance and torque balance of the main shaft inside the compressor as much as possible, thereby maximizing the static and dynamic balance of the rotor system inside the compressor, thereby reducing bearing wear and improving the service life of the compressor.

[0036] The scroll compressor device moving scroll disk 12, as shown Figure 4 As shown, the volute tooth head uses double circular arcs plus straight lines for correction near the base circle H1 of the volute line. The inner side H3 of the volute tooth has an inner circular arc correction starting point H2, and the outer side H4 of the volute tooth has an outer circular arc correction starting point H5. The middle part between the inner circular arc correction starting point H2 and the outer circular arc correction starting point H5 is double circular arcs plus straight lines for correction. This volute line design facilitates the machining of volute teeth and improves the strength and rigidity at the tooth head position.

[0037] Most existing scroll disk exhaust ports are circular. The static scroll disk exhaust port of the double-sided scroll tooth static scroll disk mechanism 13 uses a combination of arc and straight line shapes, such as... Figure 5 As shown, the left and right ends are arcs with r=3, the upper side is an arc with r=10, and the lower side is a straight line. This exhaust hole increases the exhaust area and reduces gas velocity and gas flow pulsation.

Claims

1. A single- or double-stage adjustable servo motor direct-drive symmetrical scroll compressor, characterized in that: The system includes a double-sided scroll tooth stationary scroll mechanism (13) and symmetrically arranged moving scrolls (12) on both sides. The double-sided scroll tooth stationary scroll mechanism (13) is sealed to one end of the frame (9) on both sides. The moving scrolls (12) are placed between the double-sided scroll tooth stationary scroll mechanism (13) and the frame (9) and are connected to the frame (9) through a cross slip ring (14). The scrolls on both sides of the moving scrolls (12) and the double-sided scroll tooth stationary scroll mechanism (13) mesh with each other to form multiple crescent-shaped compression chambers. The hub of the moving scrolls (12) and the frame (9) are connected by needle roller bearings (11) and self-aligning ball bearings (10), respectively. At the near end of the motor spindle (6); a flange (8) is provided between the other end of the frame (9) and one end of the motor housing (3), and a cavity is formed in the flange (8). A balance block (7) is installed in part of the motor spindle (6) in the cavity; the other end of the motor housing (3) is connected to the motor end cover (1). A ball bearing (2) is provided in the motor end cover (1) to support the far end of the motor spindle (6), and another end balance block (17) with a larger mass is provided in the motor end cover (1); the motor rotor (5) connected on the motor spindle (6) and the motor stator (4) connected on the motor housing (3) constitute a permanent magnet synchronous servo motor; The double-sided scroll tooth static scroll mechanism (13) includes two scroll surfaces, left and right, as well as an internal air intake channel and an exhaust channel, namely, a right scroll (L1) and a left scroll (L6). The left scroll (L6) is provided with a left air intake (L9) and a left air outlet (L7). The right scroll (L1) includes two independent first air intake channels (L3) and second air intake channels (L12), as well as a first exhaust channel (L11). A valve for adjusting the air intake and exhaust channels is connected between the left air outlet (L7) and the first air intake channel (L3). A second exhaust channel (L10) is provided at the bottom of the valve. The valve includes a valve stem (L4) and an upper valve plug (L5) and a lower valve plug (L8) connected to it.

2. The scroll compressor according to claim 1, characterized in that: An oil spray nozzle is provided on the flange (8) to facilitate lubrication and heat dissipation.

3. The scroll compressor according to claim 1, characterized in that: The self-aligning ball bearing (10) is coaxially mounted on the frame (9) and fixed with a bearing retaining ring (15) and a shaft elastic retaining ring (16).

4. The scroll compressor according to claim 1, characterized in that: The double-sided scroll tooth static scroll mechanism (13) is bolted to the frame (9), the frame (9) is bolted to the flange (8), and the flange (8) is bolted to the motor housing (3). The bolt holes on the double-sided scroll tooth static scroll mechanism (13), the frame (9), the flange (8), and the motor housing (3) are arranged symmetrically in the circumference to ensure that the central axis of the motor is coaxial with the central axis of the frame.

5. The scroll compressor according to claim 1, characterized in that: When the valve stem (L4) is lowered, the lower valve plug (L8) blocks the second exhaust passage (L10). The compressed gas from the left scroll plate is discharged from the left outlet (L7) and then enters the right scroll compressor through the first intake passage (L3) for secondary compression. The compressed gas is discharged from the first exhaust passage (L11). At this time, the compressor is in a series high compression ratio two-stage compression mode. When the valve stem (L4) is pulled up, the upper valve plug (L5) blocks the first intake passage (L3). At this time, the gas discharged from the left scroll compressor is directly discharged from the second exhaust passage (L10). The right scroll plate intake port cover (L13) is opened, and the right scroll compressor takes in air from the second intake passage (L12). The compressed gas is discharged from the first exhaust passage (L11). Thus, the left and right scroll compressors work simultaneously to achieve high-power air compression. At this time, the compressor is in a parallel high-power one-stage compression mode.

6. The scroll compressor according to claim 1, characterized in that: The internal rotating parts of the single- or double-stage adjustable servo motor direct-drive symmetrical scroll compressor together constitute the compressor's rotor system. The compressor's main shaft is an eccentric main shaft, which together with the moving scroll plate (12), balance block (7), self-aligning ball bearing (10), needle roller bearing (11), ball bearing (2), and end balance block (17) constitute the compressor's single-side rotor system.

7. The scroll compressor according to claim 1, characterized in that: The moving scroll plate (12) includes a first material removal part (D1), a second material removal part (D2) on the chassis, and two grooves for locking the cross slip ring, namely the first cross slip ring groove (D3) and the second cross slip ring groove (D4). The removal part and the scroll teeth form a center of mass balance design, so that its center of mass is on the same axis as the needle roller bearing (11) to achieve local static balance. The balance block (7) and the end balance block (17) ensure the force balance and torque balance of the main shaft inside the compressor as much as possible, and maximize the static balance and dynamic balance of the rotor system inside the compressor.

8. The scroll compressor according to claim 1, characterized in that: The moving scroll disk (12) uses double circular arcs plus straight line correction near the base circle (H1) of the scroll tooth head. The inner side (H3) of the scroll tooth has an inner circular arc correction starting point (H2), and the outer side (H4) of the scroll tooth has an outer circular arc correction starting point (H5). The middle part between the inner circular arc correction starting point (H2) and the outer circular arc correction starting point (H5) is double circular arc plus straight line correction.

9. The scroll compressor according to claim 1, characterized in that: The exhaust port of the double-sided spiral tooth static vortex disk mechanism (13) uses a combination of arc and straight line shapes to increase the exhaust area and reduce gas velocity and gas flow pulsation.

Images