CN101737325B - Rotary compressor - Google Patents

Abstract

The present invention provides a rotary compressor that achieves downsizing while ensuring performance and reliability in an air conditioner. The compression mechanism part (5) of the air conditioner (1) has: a cylinder (51), which has a cylinder chamber (51a), and a blade storage part (51b) extending radially outward from the cylinder chamber (51a). And the spring insertion hole (51c) extending radially inward from the outer peripheral surface; the roller (52), which is driven to rotate by the eccentric portion (4a) of the crankshaft (4); the blocking parts (53, 54), which block the working cylinder chamber (51a) is configured; the blade (55) is housed in the blade storage portion (51c) and its front end is in contact with the outer peripheral surface of the roller (52), and moves corresponding to the eccentric movement of the roller; the coil-shaped The spring (56) is disposed in the spring insertion hole (51c) and presses the blade (55) against the roller (52). The bottom of the spring insertion hole (51c) is configured such that the portion facing the front end of the spring (56) is actually the deepest.

Description

rotary compressor

technical field

The present invention relates to a rotary compressor, and is particularly suitable for a rotary compressor provided with a spring pressing a vane in a spring insertion hole of a cylinder.

Background technique

As a conventional rotary compressor, the technique disclosed in Unexamined-Japanese-Patent No. 2003-278679 (patent document 1) is known.

This rotary compressor has the following structures in an airtight container: an electric motor; a crankshaft driven by the electric motor and having an eccentric portion; and a compression mechanism portion driven by the eccentric portion. The compression mechanism includes a cylinder, a roller, a closing member, vanes, and a spring.

Further, the cylinder of the compression mechanism unit has a cylinder chamber provided at the center, a vane housing portion extending radially outward from the cylinder chamber, and a spring insertion hole extending radially inward from the outer peripheral surface. The roller is arranged in the cylinder chamber and driven to rotate by the eccentric portion of the crankshaft. The closing members are arranged on both axial sides of the cylinder so as to close the cylinder chamber. The vane is accommodated in the vane accommodation portion, and its tip abuts against the outer peripheral surface of the roller, and moves within the vane accommodation portion in response to the eccentric movement of the roller. The spring is arranged in the spring insertion hole of the cylinder, and is constituted by a coiled spring that presses the vane against the roller. The spring insertion hole has a bottom shape protruding radially inward. That is, the processing of the spring insertion hole is usually performed by a drill, and the front end is maintained at an angle of approximately 90 to 120 degrees so that the bottom of the spring insertion hole is formed into a conical shape.

[Patent Document 1]: Japanese Unexamined Patent Publication No. 2003-278679.

In recent years, as the importance of environmental protection has increased and the use of resources has become more important, downsizing of rotary compressors has been strongly desired. It has been found that there are the following problems in downsizing the rotary compressor.

When reducing the size of the rotary compressor, if similar reduction is carried out, the cylinder chamber will also be reduced, and the discharge amount per revolution will be reduced, resulting in a decrease in performance. As described above, there are restrictions on the dimensions of the cylinders, rollers, blades, etc. forming the compressor, making it impossible to easily reduce the size of the compressor. Therefore, in order to downsize the rotary compressor, it is necessary to reduce the size of components around the cylinder chamber while ensuring the size of the cylinder chamber, specifically, to reduce the outer diameter of the cylinder.

In this case, in the conventional rotary compressor, since the bottom of the spring insertion hole is conically recessed, the length dimension of the seal (in other words, the sealing area) between the spring insertion hole and the cylinder chamber may be reduced, And the performance is degraded due to leakage between the working cylinder chamber and the spring insertion hole. On the other hand, if the spring insertion hole and the spring are shortened in order to ensure the sealing length between the spring insertion hole and the cylinder chamber, the reliability may decrease because sufficient spring performance is not obtained.

In addition, when designing a rotary compressor in which the ratio of the inner diameter size to the outer diameter size of the cylinder is 0.4 or more as a structure to achieve miniaturization and ensure the pressure removal amount (pressure removal amount), in order to ensure sufficient pressure If the amount of eccentricity of the crankshaft is increased by reducing the amount, the radial length of the vane housing must be shortened. Therefore, the sliding area between the vane and the vane receiving portion in the state where it protrudes most from the vane receiving portion decreases during operation of the compressor, and it may be difficult to ensure reliability. In particular, there is a problem in achieving miniaturization while achieving large capacity. Furthermore, during operation, due to the gas force generated by the pressure difference between the two surfaces of the vane in the cylinder chamber, the vane tilts from the high-pressure side to the low-pressure side in the vane housing and slides to damage the cylinder, which may cause Reduced reliability.

Contents of the invention

An object of the present invention is to provide a rotary compressor capable of downsizing while ensuring performance and reliability.

In order to achieve the stated purpose, the present invention has the following structures in the airtight container: an electric motor; a crankshaft driven by the electric motor and having an eccentric portion; a compression mechanism portion driven by the eccentric portion, and the compression mechanism portion has: a cylinder having a cylinder chamber provided at the center, a vane receiving portion extending radially outward from the cylinder chamber, and a spring insertion hole extending radially inward from the outer peripheral surface; and a roller disposed in the cylinder chamber and The rotation is driven by the eccentric part; the blocking member is arranged on both axial sides of the cylinder so as to close the cylinder chamber; The outer peripheral surface of the roller contacts and moves corresponding to the eccentric movement of the roller; the coil-shaped spring is arranged in the spring insertion hole and presses the blade against the roller, and the rotary compressor It is characterized in that the bottom of the spring insertion hole is configured such that the part opposite to the front end of the spring is actually the deepest.

Further preferable specific configuration examples of the present invention are as follows.

(1) The ratio of the inner diameter dimension to the outer diameter dimension of the cylinder is 0.4 or more, the diameter dimension of the spring insertion hole is 0.5 or less of the axial length dimension of the cylinder, and the vane in the vane receiving portion The ratio of the gap dimension to the length dimension of the vane sliding surface in the state where the vane protrudes to the maximum is 0.0025 or less.

(2) The bottom of the spring insertion hole avoids the contact of the front end of the inserted spring on the outer peripheral side, and the center side has a depth equal to or less than the outer peripheral side.

(3) The vane is provided with a concave portion for assembling the end portion of the spring, and the axial dimension of the concave portion is 0.6 or less of the height dimension of the spring.

(4) A chamfered inclined surface is provided on the opposite side of the compression chamber of the sliding surface of the vane that slides with the cylinder.

(5) The number of turns of the closely wound portion of the spring is 4 or less.

(6) The closely wound portion of the spring has a substantially smooth shape.

According to the rotary compressor of the present invention, it is possible to achieve downsizing while ensuring performance and reliability.

Description of drawings

Fig. 1 is a longitudinal sectional view of a vertical rotary compressor according to a first embodiment of the present invention.

FIG. 2 is a perspective view in a central section of the cylinder of FIG. 1 .

FIG. 3 is a perspective view of the blade of FIG. 1 .

Fig. 4 is a plan view illustrating a sliding state of vanes of the vertical rotary compressor of Fig. 1 .

5 is a graph showing changes in the amount of wear in the first embodiment with respect to changes in the ratio between the vane gap dimension and the length dimension of the sliding surface in the state where the vanes protrude to the maximum.

6 is a graph showing changes in the amount of wear with respect to changes in the ratio of the height of the T portion to the height of the cylinder in the first embodiment.

7 is a partial sectional view showing a cylinder of a rotary compressor according to a second embodiment of the present invention.

8 is a perspective view showing a blade of a rotary compressor according to a third embodiment of the present invention.

Explanation of symbols: 1-rotary compressor, 2-airtight container, 3-electric motor, 4-crankshaft, 4a-eccentric part, 5-compression mechanism part, 6-lubricating oil, 31-stator, 32-rotor, 51-work Cylinder, 51a-operating cylinder chamber, 51b-vane storage part, 51c-spring insertion hole, 52-roller, 53, 54-blocking member, 55-vane, 55a-spring mounting recess, 56-spring, 57-exhaust valve , 58-fixing bolt, 59-suction pipe, 60-discharge pipe.

Detailed ways

Hereinafter, several embodiments of the present invention will be described using the drawings. The same symbols in the drawings of the respective embodiments represent the same or corresponding structures.

(first embodiment)

A vertical rotary compressor according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 6 . 1 is a longitudinal sectional view of a vertical rotary compressor according to this embodiment, FIG. 2 is a perspective view of a central section of the cylinder in FIG. 1 , FIG. 3 is a perspective view of a vane in FIG. 1 , and FIG. Fig. 5 is a plan view showing the sliding state of the blades of the vertical rotary compressor. FIG. 5 is a graph showing the change in the amount of wear with respect to the change in the ratio between the blade gap size and the length dimension of the sliding surface in the maximum protruding state of the blades in this embodiment. 6 is a graph showing changes in the amount of wear with respect to changes in the ratio of the height of the T portion to the height of the cylinder in the present embodiment. The rotary compressor of this embodiment is used as a component of a refrigeration cycle such as a refrigerator, an air conditioner, a heat pump water heater, and the like.

The rotary compressor 1 has the following structures in the airtight container 2: a motor 3; a crankshaft 4 driven by the motor 3 and having an eccentric portion 4a; a compression mechanism portion 5 driven by the eccentric portion 4a; and lubricating oil 6. The rotary compressor 1 is characterized in that it is more compact than the conventional art, and in particular, it is smaller in diameter.

The airtight container 2 is formed in a vertically long cylindrical shape, and lubricating oil 6 is stored at the bottom. The oil level of this lubricating oil 6 is stored at a height located in the middle of the cylinder 51 .

The motor 3 has a stator 31 fixed in the airtight container 2 and a rotor 32 rotatably arranged in the stator 31 . The motor 3 is arranged in the upper part of the airtight container 2 .

The upper part of the crankshaft 4 is inserted into the rotor 32 and fixed to the rotor 32 , whereby the crankshaft 4 and the rotor 32 rotate together. The lower part of the crankshaft 4 is inserted into the compression mechanism part 5, and the roller 52 is eccentrically rotated by the eccentric part 4a, and the compression mechanism part 5 is driven.

The compression mechanism unit 5 has the following structures: a cylinder 51 ; a roller 52 ; closing members 53 , 54 , blades 55 , spring 56 , exhaust valve 57 , and fixing bolts 58 . The compression mechanism unit 5 is arranged in the lower part of the airtight container 2 .

The basic shape of the cylinder 51 is a thick cylindrical shape, and it is arranged on the lower surface of the closing member 53 and fixed by a fixing bolt 58 . The cylinder 51 has a cylinder chamber 51a, a blade storage portion 51b, and a spring insertion hole 51c.

The cylinder chamber 51 a is provided at the center of the cylinder 51 and is formed by the circular inner peripheral surface of the cylinder 51 . In the present embodiment, the ratio of the inner diameter (diameter of the cylinder chamber 51a ) d to the outer diameter D of the cylinder 51 shown in FIG. 2 is 0.4 or more, thereby achieving miniaturization while ensuring the ejection amount.

The vane housing portion 51b forms a narrow groove linearly extending radially outward from the cylinder chamber 51a. The spring insertion hole 51c is formed as a circular hole extending radially inward from the outer peripheral surface of the cylinder 51, and is provided so as to have a portion overlapping with the vane housing portion 51b.

The roller 52 is arranged in the cylinder chamber 51 a and driven to rotate by the eccentric portion 4 a of the crankshaft 4 . The space formed by the outer peripheral surface of the roller 52 and the inner peripheral surface of the cylinder 51 is partitioned by the vane 55 , and a suction chamber and a compression chamber are formed on both sides of the vane 55 . Here, the refrigerant gas of the refrigeration cycle is sucked into the suction chamber through the suction pipe 59 . The suction chamber transitions to the compression chamber, and the refrigerant gas compressed in the compression chamber is discharged into the airtight container 2 through the discharge valve 57 . The refrigerant gas discharged into the airtight container 2 is returned to the external refrigeration cycle through the discharge pipe 60 .

The closing members 53 and 54 are arranged on both axial sides of the cylinder 51 so as to close the cylinder chamber 51 a. The closing member 53 is fixed to the airtight container 2 by welding. Then, the cylinder 51 is fixed to the closing member 53 by the fixing bolt 58 , and the closing member 54 is fixed to the cylinder 51 . Therefore, the closing member 53 , the cylinder 51 , and the closing member 54 are sequentially supported with respect to the airtight container 2 . In addition, the closing member 53 constitutes a main bearing of the crankshaft 4 , and the closing member 54 constitutes a subbearing of the crankshaft 4 .

The vane 55 is accommodated in the vane housing portion 51b, and its tip portion abuts on the outer peripheral surface of the roller 52, and moves radially within the vane housing portion 51b in response to the eccentric movement of the roller 52.

The spring 56 is formed of a coil spring, and is arranged in the spring insertion hole 51c so as to press the blade 55 against the roller 52 . The spring 56 has a closely wound portion (not shown), and the number of turns of the closely wound portion is 4 or less, for example, 3 turns. In order to provide the spring member in a limited size, the length of the closely wound portion irrespective of the elastic force is set to 4 turns or less, whereby the seal between the spring insertion hole 51c and the cylinder chamber 51a can be ensured in a limited size. The length dimension (in other words, the sealing area) can increase the effective number of turns of the spring element, thereby improving the degree of freedom in the design of the spring element, and simultaneously realizing the fixing of the spring 56 in the spring insertion hole 51c. In addition, by making the shape of the closely wound portion substantially smooth, even a short closely wound portion can reduce the influence of inclination at the time of insertion.

The above-mentioned spring insertion hole 51c is formed by end milling, and the bottom thereof constitutes a flat surface, thereby constituting the actual deepest part of the spring insertion hole 51c in the vicinity of the front end portion of the insertion side of the spring 56, which corresponds to the inner side of the spring 56. The spring insertion hole 51c may be configured to have the same depth as the above-mentioned front end portion, or may have a shallower structure as long as it has a shape that does not interfere with the spring. With the above-mentioned simple structure, even if the outer diameter of the cylinder 51 is reduced, the sealing length between the spring insertion hole 51c and the cylinder chamber 51a can be sufficiently ensured, thereby reducing the leakage of the sealing portion and suppressing the leakage. Performance degradation due to leakage, and the function of the spring 56 can be fully exhibited, thereby ensuring reliability.

For the compressor in operation, the sealing portion is a part that separates and seals off the low-temperature and low-pressure region of the suction pressure region in the cylinder chamber 51a, the pressure region during compression, and the high-temperature and high-pressure region of the output pressure region in the container. . When a leak occurs in the sealing portion, high-temperature and high-pressure gas flows into the compression chamber region, causing heating and pressure rise of the suction gas, thereby degrading the performance.

In this embodiment, the diameter dimension a of the spring insertion hole 51c shown in FIG. In this way, by reducing the diameter dimension a of the spring insertion hole 51c, the height dimension of the T portion (in other words, the sealing area) that is the sealing surface of the vane housing portion 51b located in the vertical direction of the spring insertion hole 51c can be increased (in other words, the sealing area) can be enlarged. The surface pressure at the T portion of the blade 55 is suppressed low. Various experiments have been conducted, and it has been found that as the ratio of the height dimension of the T portion of the vane housing portion 51b to the height dimension H of the cylinder 51 decreases, the amount of wear of the vane sliding portion increases. As shown in FIG. 6, if the When the ratio is less than 0.5, the wear amount of the vane sliding portion rapidly increases. In other words, it can be seen that when the ratio is 0.5 or more, a region where the amount of wear is stable can be obtained.

Furthermore, if the vane 55 inclines excessively into the vane housing portion 51b of the cylinder 51 during operation of the compressor, the possibility of the contact form between the cylinder 51 and the vane 55 approaching a state of line contact or point contact from a surface contact state increases. high. As shown in FIG. 4 , the vane gap dimension of the vane housing portion 51b is represented by ΔV, and the length dimension of the vane sliding surface in the state where the vane 55 protrudes to the roller side to the maximum is represented by E. Here, it can be seen that as ΔV/E increases, the wear amount of the vane sliding portion increases, and in particular, when ΔV/E exceeds 0.0025, the wear amount of the vane sliding portion rapidly increases. In other words, when ΔV/E is 0.0025 or less, a wear amount stable region can be obtained.

In addition, it is preferable that the height b of the spring mounting recess 55a of the vane 55 shown in FIG. Thereby, it is possible to have the same relationship as the relationship shown in FIG. 6 . As shown in FIG. 3 , when the mounting recess is tapered, even if a part near the end is 0.6 or less, the same effect can be obtained by arranging the main range of 0.5 or less.

According to the present embodiment, even if the rotary compressor 1 is downsized, the sealing length between the cylinder 51 and the vane 55 can be ensured, and a good sliding state between the vane 55 and the cylinder 51 can be ensured. Accordingly, low-cost and highly reliable rotary compressor 1 can be realized. As the size of the rotary compressor 1 is reduced, the size of the assembled product can also be reduced, and thus it can contribute to resource saving in manufacturing, reduction of transportation load, and the like.

(second embodiment)

Next, a rotary compressor according to a second embodiment of the present invention will be described using FIG. 7 . 7 is a partial sectional view showing a cylinder of a rotary compressor according to a second embodiment of the present invention. This second embodiment is different from the first embodiment in the points described next, and is basically the same as the first embodiment in other points, so redundant descriptions will be omitted.

In the second embodiment, the bottom portion provided on the front end side of the spring insertion hole 51c of the cylinder 51 is composed of an outer peripheral portion 51c1 to which the end portion of the spring 56 is assembled and a central portion 51c2 protruding inwardly from the end portion of the spring 56. . According to this second embodiment, in addition to improving the sealing performance, there is also an effect of increasing the contact area between the vane 55 and the cylinder 51, and contributes to an improvement in reliability. The effect of the second embodiment becomes more pronounced as the degree of downsizing of the compressor progresses and size constraints become larger.

(third embodiment)

Next, a rotary compressor according to a third embodiment of the present invention will be described using FIG. 8 . 8 is a perspective view showing a blade of a rotary compressor according to a third embodiment of the present invention. This third embodiment is different from the first embodiment in the points described next, and is basically the same as the first embodiment in other points, so redundant descriptions will be omitted.

In this third embodiment, a tapered inclined surface is provided at the end portion of the vane 55 on the side opposite to the compression chamber of the sliding surface that slides with the cylinder 51 . As a result, even when the vane 55 slides in the vane housing portion 51b in an inclined state, an increase in the surface pressure of the vane sliding portion can be suppressed, and a sliding method close to surface contact can be realized. In addition, even if the angle of the tapered shape is small, it is effective, but it is preferable to exceed the angle at which the blade 55 can incline according to the gap in the blade housing portion 51b.

Claims (7)

1. A rotary compressor, which has in an airtight container: an electric motor; a crankshaft driven by the electric motor and having an eccentric portion; a compression mechanism portion driven by the eccentric portion, The compression mechanism unit includes: a cylinder having a cylinder chamber provided at the center, a vane receiving portion extending radially outward from the cylinder chamber, and a spring insertion hole extending radially inward from the outer peripheral surface; and a roller having Arranged in the working cylinder chamber and driven to rotate by the eccentric portion; a blocking member arranged on both axial sides of the working cylinder so as to close the working cylinder chamber; a vane accommodated in the vane housing and its front end abuts against the outer peripheral surface of the roller, and moves corresponding to the eccentric movement of the roller; a coil-shaped spring is arranged in the spring insertion hole and presses the vane against the roller , The rotary compressor is characterized in that, The bottom of the spring insertion hole is configured such that the part opposite to the front end of the spring is actually the deepest, The ratio of the inner diameter dimension to the outer diameter dimension of the cylinder is 0.4 or more, the diameter dimension of the spring insertion hole is 0.5 or less of the axial length dimension of the cylinder, and the vane gap dimension and The length-dimension ratio of the vane sliding surface in the state where the vane protrudes to the maximum is 0.0025 or less. 2. The rotary compressor of claim 1, wherein: The bottom of the spring insertion hole is formed as a flat surface by end milling. 3. The rotary compressor of claim 1, wherein: The bottom of the spring insertion hole includes: an outer peripheral portion assembled with an end portion of the spring; and a central portion protruding inwardly of the end portion of the spring. 4. The rotary compressor of claim 1, wherein: The blades are provided with recesses that fit into the ends of the springs, An axial dimension of the recess is 0.6 or less of a height dimension of the cylinder. 5. The rotary compressor of claim 1, wherein: A chamfered inclined surface is provided on the opposite side of the compression chamber of the sliding surface of the blade on which the cylinder slides. 6. The rotary compressor of claim 1, wherein: The number of turns of the closely wound portion of the spring is 4 or less. 7. The rotary compressor of claim 6, wherein: The closely wound portion of the spring has a substantially smooth shape.

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