JP2017066919A - Compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compressor for enhancing its volumetric efficiency by reducing a clearance between the outer peripheral face of a roller and the inner peripheral face of a cylinder on the suction side.SOLUTION: In the compressor having the cylinder decentered to the suction side with respect to the bearing center of a shaft, part of the outer peripheral face of a roller 41 is shaped so that a distance D2 from a center O3 of the inner peripheral face of the roller 41 is continuously changed with respect to an angle around the center O3. An average value for the distance D2 on the further suction side than a straight L4 extending in the extending direction of a blade 42 is greater than an average value for the distance D2 on the further discharge side than the straight L4.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a compressor for compressing a refrigerant.

  Patent Document 1 discloses a compression provided with a cylinder in which a compression chamber is formed, a roller disposed in the compression chamber of the cylinder, and a partition plate that partitions a space between the cylinder and the roller into a high pressure chamber and a low pressure chamber. A machine is disclosed. The roller is mounted on the eccentric part of the crankshaft, and moves along the peripheral wall surface of the compression chamber as the crankshaft rotates. In such a compressor, when the pressure difference between the high-pressure chamber and the low-pressure chamber increases, refrigerant and lubricating oil from the gap between the outer peripheral surface of the roller and the peripheral wall surface of the compression chamber easily leak.

  In the compressor of Patent Document 1, an eccentric assembly is performed in which the center of the crankshaft is not aligned with the center of the inner diameter (compression chamber) of the cylinder and is positioned on the high-pressure chamber side with respect to the axis of the partition plate. Yes. As a result, when the rotation angle of the crankshaft from the position where the roller is at the top dead center is greater than 180 ° and the pressure difference between the high pressure chamber and the low pressure chamber is relatively large, the outer peripheral surface of the roller and the compression chamber The gap between the peripheral wall and the wall becomes the smallest. Therefore, when the pressure difference between the high pressure chamber and the low pressure chamber becomes relatively large, the amount of refrigerant and lubricating oil leaking from the gap between the outer peripheral surface of the roller and the peripheral wall surface of the compression chamber is reduced, and the volumetric efficiency is increased. Can be increased.

JP 2002-98075 A

  However, when the eccentric assembly as described above is performed, the gap (suction) between the outer peripheral surface of the roller and the peripheral wall surface of the compression chamber from the position where the roller is at the top dead center until the rotation angle of the crankshaft becomes 180 °. The gap on the side increases. At this time, the pressure difference between the high-pressure chamber and the low-pressure chamber is relatively small, but it is desired to further increase the volumetric efficiency of the compressor. Therefore, the clearance on the suction side is reduced to reduce refrigerant and lubrication from the clearance on the suction side. It is also necessary to reduce the amount of oil leakage.

  Therefore, the present invention has been made to solve the above-described problems, and it is possible to reduce the gap between the outer peripheral surface of the roller and the peripheral wall surface of the compression chamber on the suction side, thereby increasing the volume efficiency. It aims at providing the compressor which can be performed.

  A compressor according to a first aspect of the present invention includes a compression chamber and a cylinder having a blade accommodating portion communicating with the compression chamber, a piston disposed inside the compression chamber and the blade accommodating portion, and a drive shaft having an eccentric portion. The piston is disposed in the compression chamber and attached to the eccentric part of the drive shaft, and extends from the outer peripheral surface of the roller and can be advanced and retracted with respect to the blade housing part. The cylinder is eccentric to the suction side with respect to the bearing center of the drive shaft, and at least a part of the outer peripheral surface of the roller is a distance from the center of the inner peripheral surface of the roller Changes continuously with respect to the angle around the center, and the average value of the distance on the suction side from the first straight line extending in the extending direction of the blade is closer to the discharge side than the first straight line. Wherein longer than the average value of the distance that.

  In this compressor, even if an eccentric assembly is performed in which the cylinder is eccentric to the suction side with respect to the bearing center of the drive shaft, the gap between the outer peripheral surface of the roller and the peripheral wall surface of the compression chamber on the suction side is reduced, Volumetric efficiency can be improved.

  A compressor according to a second aspect of the present invention is the compressor according to the first aspect, wherein at least a part of the outer peripheral surface of the roller is laser processed.

  In this compressor, the distance from the center of the inner peripheral surface of the roller to the outer peripheral surface of the roller is continuously changed with respect to the angle around the center by performing laser processing on the outer peripheral surface of the roller and expanding it. Can be processed into such a shape.

  A compressor according to a third invention is the compressor according to the first or second invention, wherein the cross section of the compression chamber of the cylinder in a plane perpendicular to a second straight line extending in the extending direction of the blade housing chamber is The average value of the area on the suction side with respect to the second straight line is smaller than the average value of the area on the discharge side with respect to the second straight line.

  In this compressor, not only the piston side but also the cylinder side has a shape that reduces the gap between the outer peripheral surface of the roller and the peripheral wall surface of the compression chamber on the suction side, thereby reducing the processing amount of each part. Since it can be made smaller, variations in processing can be suppressed.

  A compressor according to a fourth invention is the compressor according to the third invention, wherein at least a part of a wall surface defining the compression chamber of the cylinder is subjected to laser processing.

  In this compressor, the wall surface defining the compression chamber of the cylinder is subjected to laser processing to be expanded so that the average value of the area on the suction side with respect to the second straight line is easily larger than the area on the discharge side with respect to the second straight line. It can be processed into a shape that is smaller than the average value.

  As described above, according to the present invention, the following effects can be obtained.

  In the first invention, even if the eccentric assembly is performed in which the cylinder is eccentric to the suction side with respect to the bearing center of the drive shaft, the gap between the outer peripheral surface of the roller and the peripheral wall surface of the compression chamber on the suction side is reduced. , Volumetric efficiency can be improved.

  In the second invention, the outer peripheral surface of the roller is subjected to laser processing and expanded so that the distance from the center of the inner peripheral surface of the roller to the outer peripheral surface of the roller is continuous with respect to the angle around the center. It can be processed into a changing shape.

  In the third aspect of the invention, not only the piston side but also the cylinder side has a shape that reduces the gap between the outer peripheral surface of the roller and the peripheral wall surface of the compression chamber on the suction side. Can be reduced, so that variations in processing can be suppressed.

  In the fourth aspect of the invention, the wall surface defining the compression chamber of the cylinder is expanded by applying laser processing so that the average value of the area on the suction side with respect to the second straight line is easily set on the discharge side with respect to the second straight line. It can be processed into a shape that is smaller than the average area.

It is a schematic sectional drawing of the compressor which concerns on embodiment of this invention. It is sectional drawing along the AA line of FIG. 1, Comprising: It is a figure which shows operation | movement of the piston in a cylinder. It is the figure which looked at the front head of the compressor shown in Drawing 1 from the lower part in a figure. It is a figure which shows the positional relationship of the center of the internal peripheral surface of the cylinder of the compressor shown in FIG. 1, and the bearing center of a shaft. It is a figure for demonstrating the shape of the outer peripheral surface of the roller in the piston of the compressor shown in FIG. It is a figure for demonstrating the shape of the internal peripheral surface of the cylinder of the compressor shown in FIG. It is a graph which shows the relationship between the crank angle in the compressor of a prior art example, an Example, and the modification 1 and radial direction clearance gap. It is a graph which shows the relationship between the crank angle and radial direction clearance in the compressor of a prior art example and the modification 2. It is a graph which shows the relationship between the crank angle and radial direction clearance in the compressor of the prior art example and the modification 3. It is a graph which shows the relationship between the crank angle and radial direction clearance in the compressor of a prior art example and the modification 4.

Hereinafter, embodiments of the present invention will be described.
The present embodiment is an example in which the present invention is applied to a one-cylinder rotary compressor.
As shown in FIG. 1, the compressor 1 of the present embodiment includes a sealed casing 2, a compression mechanism 10 and a drive mechanism 6 disposed in the sealed casing 2. In FIG. 1, hatching indicating a cross section of the drive mechanism 6 is omitted. For example, the compressor 1 is used by being incorporated in a refrigeration cycle such as an air conditioner, and compresses a refrigerant (for example, R32) introduced from a suction pipe 3 to be described later and discharges the refrigerant from the discharge pipe 4. The compressor 1 will be described below with the vertical direction in FIG.

  The hermetic casing 2 is a cylindrical container with both ends closed, and an upper portion thereof has a discharge pipe 4 for discharging a compressed refrigerant and a coil of a stator 7b (to be described later) of the drive mechanism 6 as a current. Is provided with a terminal terminal 5. In FIG. 1, the wiring connecting the coil and the terminal terminal 5 is not shown. Also. A suction pipe 3 for introducing a refrigerant into the compressor 1 is provided on the side of the closed casing 2. In addition, a lubricating oil L for smoothing the operation of the sliding portion of the compression mechanism 10 is stored in the lower part of the sealed casing 2. Inside the sealed casing 2, a drive mechanism 6 and a compression mechanism 10 are arranged vertically.

  The drive mechanism 6 is provided to drive the compression mechanism 10 and includes a motor 7 serving as a drive source and a shaft 8 attached to the motor 7.

  The motor 7 includes a substantially annular stator 7b fixed to the inner peripheral surface of the hermetic casing 2, and a rotor 7a disposed on the radially inner side of the stator 7b via an air gap. . The rotor 7a has a magnet (not shown), and the stator 7b has a coil. The motor 7 rotates the rotor 7a by an electromagnetic force generated by passing a current through the coil. Further, the outer peripheral surface of the stator 7b is not in close contact with the inner peripheral surface of the hermetic casing 2 over the entire periphery. The outer peripheral surface of the stator 7b extends in the vertical direction and has a space above and below the motor 7. A plurality of recesses (not shown) to be communicated are formed side by side in the circumferential direction.

  The shaft 8 is provided to transmit the driving force of the motor 7 to the compression mechanism 10, is fixed to the inner peripheral surface of the rotor 7a, and rotates integrally with the rotor 7a. The shaft 8 has an eccentric portion 8a at a position in the compression chamber 31 described later. The eccentric portion 8 a is formed in a columnar shape, and its axis is eccentric from the rotation center of the shaft 8. A roller 41 (to be described later) of the compression mechanism 10 is mounted on the eccentric portion 8a.

  An oil supply passage 8b extending in the vertical direction is formed inside the lower half of the shaft 8. A spiral blade-shaped pump member (not shown) for sucking the lubricating oil L into the oil supply passage 8b as the shaft 8 rotates is inserted into the lower end portion of the oil supply passage 8b. Further, the shaft 8 is formed with a plurality of discharge holes 8 c for discharging the lubricating oil L in the oil supply passage 8 b to the outside of the shaft 8.

  The compression mechanism 10 includes a front head 20 that is fixed to the inner peripheral surface of the hermetic casing 2, a muffler 11 that is disposed above the front head 20, a cylinder 30 that is disposed below the front head 20, and a cylinder 30. Is provided with a piston 40 and a rear head 50 disposed below the cylinder 30. Although details will be described later, as shown in FIG. 2, the cylinder 30 is a substantially annular member, and a compression chamber 31 is formed at the center thereof. The cylinder 30 is fixed to the lower side of the front head 20 together with the rear head 50 by bolts. In FIG. 2, bolt holes formed in the cylinder 30 are omitted.

  As shown in FIGS. 1 and 3, the front head 20 is a substantially annular member, and a bearing hole 21 into which the shaft 8 is rotatably inserted is formed at the center thereof. The outer peripheral surface of the front head 20 is fixed to the inner peripheral surface of the sealed casing 2 by spot welding or the like. The lower surface of the front head 20 closes the upper end of the compression chamber 31 of the cylinder 30. The front head 20 has a discharge hole 22 for discharging the refrigerant compressed in the compression chamber 31. The discharge hole 22 is formed in the vicinity of a blade accommodating portion 33 (described later) of the cylinder 30 when viewed from the up-down direction. Although not shown, a valve mechanism that opens and closes the discharge hole 22 according to the pressure in the compression chamber 31 is attached to the upper surface of the front head 20. In addition, a plurality of oil return holes 23 are formed in the circumferential direction in the radially outer portion of the front head 20 than the cylinder 30. The front head 20 is made of a metal material.

  The rear head 50 is a substantially annular member, and a bearing hole 51 through which the shaft 8 is rotatably inserted is formed at the center thereof. The bearing hole 51 of the rear head 50 is formed at a position aligned with the bearing hole 21 of the front head 20 in the vertical direction. The upper end surface of the rear head 50 closes the lower end of the compression chamber 31 of the cylinder 30. The rear head 50 is made of a metal material.

  The muffler 11 is provided to reduce noise when the refrigerant is discharged from the discharge hole 22 of the front head 20. The muffler 11 is attached to the upper surface of the front head 20 with bolts, and forms a muffler space M between the front head 20 and the muffler 11. Although not shown, the muffler 11 is formed with a muffler discharge hole for discharging the refrigerant in the muffler space M.

  As shown in FIGS. 1 and 2, the cylinder 30 is formed with the above-described compression chamber 31, a suction hole 32 for introducing a refrigerant into the compression chamber 31, and a blade accommodating portion 33. The cylinder 30 is made of a ferrous metal material. 2 is a cross-sectional view taken along the line AA in FIG. 1, and the discharge holes 22 of the front head 20 are not originally shown, but are shown for convenience of explanation.

  The suction hole 32 extends in the radial direction of the cylinder 30. One end of the suction hole 32 is a suction port 32 a that is opened in the peripheral wall surface of the compression chamber 31. The tip of the suction pipe 3 is fitted into the end of the suction hole 32 opposite to the suction port 32a.

  The blade accommodating portion 33 penetrates the cylinder 30 in the vertical direction and communicates with the compression chamber 31. The blade accommodating portion 33 extends in the radial direction of the compression chamber 31. The blade accommodating portion 33 is formed at a position between the suction hole 32 and the discharge hole 22 of the front head 20 when viewed from the vertical direction. A pair of bushes 34 is disposed in the blade accommodating portion 33. The pair of bushes 34 is formed in a shape in which a substantially cylindrical member is divided into half. A blade 42 that is a part of the piston 40 is disposed between the pair of bushes 34. The pair of bushes 34 can swing in the circumferential direction in the blade housing portion 33 with the blade 42 disposed therebetween.

  The cylinder 30 is eccentrically assembled so as to be eccentric to the suction side with respect to the bearing center of the shaft 8. That is, as shown in FIG. 4, the center O1 of the inner peripheral surface that defines the compression chamber 31 of the cylinder 30 is the bearing center O2 (that is, the bearing hole 21 of the front head 20, the bearing hole 51 of the rear head 50, and the shaft 8). Is located on the side (right side in FIG. 4) where the suction hole 32 is formed. More specifically, the center O1 of the inner peripheral surface of the cylinder 30 is a straight line L1 that passes through the center of the blade accommodating portion 33 and extends in the extending direction of the blade accommodating portion 33, and a straight line that is orthogonal to the straight line L1 in plan view. Thus, the compression chamber 31 is located at the intersection with the straight line L2 passing through the widest portion. And the bearing center O2 is located in the side (left side in FIG. 4) in which the discharge hole 22 is formed rather than the straight line L1 on the straight line L2. The distance D1 between the center O1 of the inner peripheral surface of the cylinder 30 and the bearing center O2 is about 10 μm to 30 μm (25 μm in this example).

  The piston 40 is made of an iron-based metal material, and includes an annular roller 41 and a blade 42 that extends radially outward from the outer peripheral surface of the roller 41. As shown in FIG. 2, the roller 41 is mounted on the outer peripheral surface of the eccentric portion 8 a so as to be relatively rotatable, and is disposed in the compression chamber 31. The blade 42 is disposed between the pair of bushes 34 disposed in the blade accommodating portion 33 so as to advance and retreat.

  Further, the outer diameter of the roller 41 is a small gap (hereinafter, this gap is referred to as a radial gap d) between the outer peripheral surface of the roller 41 and the peripheral wall surface of the compression chamber 31 when mounted on the eccentric portion 8a. The size is such that the Therefore, as shown in FIGS. 2B to 2D, when the blade 42 protrudes from the blade accommodating portion 33 toward the compression chamber 31, the outer peripheral surface of the roller 41 and the peripheral wall surface of the compression chamber 31 The space formed between the two is partitioned by the blade 42 into a low pressure chamber 31a and a high pressure chamber 31b.

  Next, the shape of the piston 40 will be described in detail with reference to FIG. The piston 40 of the present embodiment performs laser quenching on the outer peripheral surface of a roller having a conventional shape in which the outer peripheral surface of the roller is equidistant from the center of the inner peripheral surface of the roller. The distance D2 from the center O3 to the outer peripheral surface of the roller 41 is configured to continuously change with respect to the angle around the center O3. Specifically, the suction hole 32 side (the right side in FIG. 5) from the position where the blade 42 is provided on the outer peripheral surface of the roller 41, and the extending direction of the blade 42 from the center O <b> 3 of the inner peripheral surface of the roller 41. Quenching is performed by irradiating a laser beam to a portion where the angle formed by the extending straight line is about 270 °. By irradiating the laser beam to the piston 40 formed of the iron-based metal material to a temperature higher than the recrystallization temperature, the composition of the portion irradiated with the laser beam changes and the volume expands. Since the degree of volume expansion increases as the laser output increases, the distance D2 can be changed steplessly by performing quenching while adjusting the laser output. The average value of the distance D2 on the suction side (right side in FIG. 5) is longer than the average value of the distance D2 on the discharge side (left side in FIG. 5) than the straight line L4 extending in the extending direction of the blade 42.

  Here, a more specific shape of the outer peripheral surface of the roller 41 shown in FIG. 5 will be described. The roller 41 is formed based on a conventional roller having a radius of 12.5 mm on the inner peripheral surface and a radius of 18 mm on the outer peripheral surface. In FIG. 5, the outer peripheral surface of a conventional roller is indicated by a broken line. In FIG. 5, the difference from the conventional shape is emphasized for explanation. Actually, the difference from the conventional shape is about several μm to several tens of μm. The outer peripheral surface of the roller 41 is on a straight line extending radially from the center O3 of the inner peripheral surface of the roller 41, and the distance from the spiral smooth curve C1 around the center O3 shown in FIG. 5 is equal (18 mm in this example). ) Matches the curve connecting the points.

  That is, for example, the straight line extending in the extending direction of the blade 42 from the center O3 of the inner peripheral surface of the roller 41 is 0 °, and the angle θ2 around the center O3 is 10 °, 30 °, 50 °, 70 °, 90 °, When 18 straight lines L5 that are 110 °, 130 °, 150 °, 170 °, 190 °, 210 °, 230 °, 250 ° 270 °, 290 °, 310 °, 330 °, and 350 ° are drawn, θ2 = The 230 ° straight line L5 intersects with the curve C1 at a location where the distance from the center O3 is 0.002 mm, and the outer surface of the roller 41 at a location where the distance from the center O3 is 18.002 mm (= 0.002 mm + 18 mm). Crosses. A straight line L5 of θ2 = 210 ° intersects the curve C1 at a position where the distance from the center O3 is 0.004 mm, and the outer periphery of the roller 41 at a position where the distance from the center O3 is 18.004 mm (= 0.004 mm + 18 mm). Crosses the face. A straight line L5 of θ2 = 190 ° intersects the curve C1 at a position where the distance from the center O3 is 0.006 mm, and the outer periphery of the roller 41 at a position where the distance from the center O3 is 18.006 mm (= 0.006 mm + 18 mm). Crosses the face. Further, the straight line L5 of θ2 = 10 ° intersects the curve C1 at a position where the distance from the center O3 is 0.024 mm, and the roller 41 at a position where the distance from the center O3 is 18.024 mm (= 0.024 mm + 18 mm). It intersects with the outer peripheral surface.

  That is, it can be said that the outer peripheral surface of the roller 41 continuously changes in the distance D2 from the center O3 as the center O3 of the inner peripheral surface of the roller 41. In addition, it can be said that the outer peripheral surface of the roller 41 has a radius that does not change and is a trajectory that is formed when the center follows the trajectory of the curve C1. In order to simplify the description, the straight lines L5 are set at 20 ° intervals for the sake of description, but in practice, a smooth roller outer peripheral surface shape can be obtained by setting the intervals to be finer.

  Next, the shape of the cylinder 30 will be described in detail with reference to FIG. The cylinder 30 of the present embodiment is configured such that the inner peripheral surface of the cylinder 30 is subjected to laser quenching on the inner peripheral surface of the cylinder having a conventional shape in which the inner peripheral surface of the cylinder is equidistant from the center of the inner peripheral surface of the cylinder. The distance D3 from the center O1 of the surface to the outer peripheral surface of the cylinder 30 is continuously changed with respect to the angle around the center O1. Similar to the outer peripheral surface of the roller 41 of the piston 40, the blade accommodating portion from the center O <b> 1 of the inner peripheral surface of the cylinder 30 from the suction hole 32 side (right side in FIG. 6) to the blade accommodating portion 33 in the inner peripheral surface of the cylinder 30. The laser beam is irradiated while adjusting the laser output to a portion where the angle formed by the straight line extending in the extending direction of 33 is about 270 °, and the distance D3 is changed steplessly. The cross section of the compression chamber 31 of the cylinder 30 in the plane orthogonal to the straight line L1 along the extending direction of the blade accommodating portion 33 is from the area (the straight line L1 passes) the area closer to the suction hole 32 (right side in FIG. 6) than the straight line L1. The average value of the area reaching the inner peripheral surface of the cylinder 30 to the right) is the area closer to the discharge hole 22 (left side in FIG. 6) than the straight line L1 (the inner peripheral surface of the cylinder 30 from the position through which the straight line L1 passes). Smaller than the average value of the area of the portion leading to

  Here, a more specific shape of the inner peripheral surface of the cylinder 30 shown in FIG. 6 will be described. The cylinder 30 is assumed to be formed on the basis of a conventional cylinder having an inner peripheral surface radius of 23 mm. In FIG. 6, the inner peripheral surface of the cylinder 30 having a conventional shape is indicated by a broken line. In FIG. 6, for the sake of explanation, the difference from the conventional shape is emphasized. Actually, the difference from the conventional shape is about several μm to several tens of μm. The inner circumferential surface of the cylinder 30 has a distance in a certain direction from the center O1 of the inner circumferential surface of the cylinder 30 with respect to a direction symmetric with respect to a direction from the center O1 from a predetermined distance (23 mm in this example). It corresponds to a curve connecting points that are distances obtained by subtracting the distance to the spiral smooth curve C2 around the center O1 shown.

  That is, for example, a straight line extending from the center O1 of the inner peripheral surface of the cylinder 30 in the extending direction of the blade accommodating portion 33 is 0 °, and the angle θ3 around the center O1 is 10 °, 30 °, 50 °, 70 °, 90 When drawing 18 straight lines L6 that are °, 110 °, 130 °, 150 °, 170 °, 190 °, 210 °, 230 °, 250 ° 270 °, 290 °, 310 °, 330 °, 350 °, On the straight line L6 of θ3 = 50 °, it intersects with the curve C2 at a position where the distance from the center O1 is 0.002 mm, and a straight line of θ3 = 230 ° extending in a point-symmetrical direction with the straight line L6 of θ3 = 50 °. L6 intersects the inner peripheral surface of the cylinder 30 at a position where the distance from the center O1 is 22.998 mm (= 23 mm−0.002 mm). The straight line L6 with θ3 = 30 ° intersects the curve C2 at a position where the distance from the center O1 is 0.004 mm, and the straight line L6 with θ3 = 210 ° extending in a point-symmetrical direction with the straight line L6 with θ3 = 30 °. Is intersected with the inner peripheral surface of the cylinder 30 at a location where the distance from the center O1 is 22.996 mm (= 23 mm−0.004 mm). A straight line L6 with θ3 = 10 ° intersects the curve C2 at a position with a distance of 0.006 mm from the center O1, and a straight line L6 with θ3 = 190 ° extending in a point-symmetrical direction with the straight line L6 with θ3 = 10 °. Is intersected with the inner peripheral surface of the cylinder 30 at a location where the distance from the center O1 is 22.994 mm (= 23 mm−0.006 mm). Further, the straight line L6 of θ3 = 190 ° intersects the curve C2 at a position where the distance from the center O1 is 0.024 mm, and θ3 = 10 ° extending in a point-symmetrical direction with the straight line L6 of θ3 = 190 °. The straight line L6 intersects with the inner peripheral surface of the cylinder 30 at a position where the distance from the center O1 is 22.976 mm (= 23 mm−0.024 mm). In order to simplify the description, the straight line L6 is set at an interval of 20 ° for the sake of description. However, in practice, a smooth cylinder inner peripheral surface shape can be obtained by setting the interval to a finer interval.

  Here, the size of the radial gap d between the peripheral wall surface of the compression chamber 31 (the inner peripheral surface of the cylinder 30) and the outer peripheral surface of the roller 41 will be described with reference to FIG. In the graph shown by a solid line in FIG. 7, the cylinder and the roller have the conventional shapes, that is, the inner peripheral surface of the cylinder is equidistant from the center of the inner peripheral surface of the cylinder, and the outer peripheral surface of the roller is the inner peripheral surface of the roller. The radial gap d is shown when it is equidistant from the center. As described above, since the cylinder is eccentrically assembled so as to be eccentric to the suction side with respect to the bearing center of the shaft, the size of the radial gap d increases as the roller is displaced as the shaft rotates. Change. Specifically, when the cylinder and roller are conventional shapes, the radial clearance d is determined by the crank angle θ1 (the rotation angle of the shaft when the state where the piston is at top dead center is 0 °). Is the largest at about 0.06 mm at the portion where the angle is 90 °, and then gradually decreases, and is the smallest at about 0.01 mm at the portion where the crank angle θ1 is 270 °. By performing the eccentric assembly, it is possible to reduce the radial gap d in the vicinity of the portion where the pressure difference between the high pressure chamber 31b and the low pressure chamber 31a is the largest (the portion where the crank angle θ1 is 270 °). On the other hand, when the shape of the cylinder and the roller is a conventional shape, the maximum value of the radial gap d is as large as about 0.06 mm.

  5 and 6, the radial gap d between the peripheral wall surface of the compression chamber 31 and the outer peripheral surface of the roller 41 in this embodiment is a broken line in FIG. As shown in the figure, as in the case where the cylinders and rollers have a conventional shape, the portion where the crank angle θ1 is 270 ° is the smallest and is about 0.01 mm. The radial gap d is the largest in the vicinity where the crank angle θ1 is 120 °, and is about 0.03 mm. That is, the maximum value of the radial gap d in the present embodiment is sufficiently smaller than the maximum value (0.06 mm) of the radial gap d when the cylinder and the roller have the conventional shape.

  However, the radial gap d is measured as a gap between the peripheral wall surface of the compression chamber 31 and the outer peripheral surface of the roller 41 when the compression mechanism 10 is assembled, and during operation of the compressor 1, It decreases from the time of assembly due to the oil film thickness of the bearing portion that changes depending on operating conditions such as pressure conditions, centrifugal force acting on the piston 40, and thermal expansion. However, the tendency of the change in the radial gap d with respect to the crank angle θ1 is as shown in FIG.

Next, operation | movement of the compression mechanism 10 is demonstrated with reference to Fig.2 (a)-FIG.2 (d).
FIG. 2A shows a state where the piston 40 is at the top dead center, and FIG. 2B shows a state when the compression of the refrigerant is started. 2 (c) and 2 (d) show a state in which the shaft 8 has rotated 180 ° (bottom dead center) and 270 °, respectively, from the state of FIG. 2 (a).

  When the shaft 8 is rotated by driving the motor 7 while supplying the refrigerant from the suction pipe 3 to the compression chamber 31 through the suction hole 32, as shown in FIGS. 2 (a) to 2 (d), the eccentric portion The roller 41 attached to 8 a moves along the peripheral wall surface of the compression chamber 31. Thereby, the refrigerant is compressed in the compression chamber 31. Hereinafter, the process of compressing the refrigerant will be described in detail.

  The eccentric portion 8a rotates in the direction of the arrow in the figure from the state of FIG. 2A, and as shown in FIG. 2B, the outer peripheral surface of the roller 41 is on the downstream side in the moving direction of the roller 41 in the suction hole 32. When the end portion (that is, the end portion on the peripheral wall surface of the compression chamber 31 on the downstream side of the suction port 32a (the portion indicated by E1 in the figure)) is closest, the outer peripheral surface of the roller 41 and the periphery of the compression chamber 31 A space formed by the wall surface is partitioned into a low pressure chamber 31a and a high pressure chamber 31b. Thereafter, when the eccentric portion 8a further rotates, as shown in FIGS. 2C and 2D, the volume of the low-pressure chamber 31a increases, so that the inside of the low-pressure chamber 31a passes through the suction pipe 3 through the suction hole 32. The refrigerant is sucked in. At the same time, since the volume of the high pressure chamber 31b is reduced, the refrigerant is compressed in the high pressure chamber 31b.

  Then, when the pressure in the high pressure chamber 31b becomes equal to or higher than a predetermined pressure, the valve mechanism provided in the front head 20 opens, and the refrigerant in the high pressure chamber 31b passes through the discharge hole 22 and the muffler space M Discharged. Thereafter, the state returns to the state of FIG. 2A, and the discharge of the refrigerant from the high pressure chamber 31b is completed. By repeating this process, the refrigerant supplied from the suction pipe 3 to the compression chamber 31 is continuously compressed and discharged. The refrigerant discharged into the muffler space M is discharged out of the compression mechanism 10 through a muffler discharge hole (not shown) of the muffler 11.

  The refrigerant discharged from the compression mechanism 10 as described above passes through an air gap between the stator 7b and the rotor 7a and is finally discharged out of the sealed casing 2 from the discharge pipe 4. . At this time, a part of the lubricating oil L supplied into the compression chamber 31 from the discharge hole 8c of the shaft 8 is discharged into the muffler space M from the discharge hole 22 together with the refrigerant, and then the muffler discharge hole (not shown) of the muffler 11. ) To the outside of the compression mechanism 10. A part of the lubricating oil L discharged to the outside of the compression mechanism 10 is returned to the storage portion at the lower part of the sealed casing 2 through the oil return hole 23 of the front head 20. Further, another part of the lubricating oil L discharged to the outside of the compression mechanism 10 is formed on the outer peripheral surface of the stator 7b after passing through the air gap between the stator 7b and the rotor 7a together with the refrigerant. Between the recessed portion (not shown) and the inner peripheral surface of the sealed casing 2, and through the oil return hole 23 of the front head 20, is returned to the storage section at the lower portion of the sealed casing 2.

  As described above, in the compressor 1 of the present embodiment, the cylinder 30 is eccentric to the suction side with respect to the bearing center of the shaft 8, and a part of the outer peripheral surface of the roller 41 is the center O3 of the inner peripheral surface of the roller 41. The distance D2 from the center continuously changes with respect to the angle around the center O3. The average value of the distance D2 on the suction side with respect to the straight line L4 extending in the extending direction of the blade 42 is longer than the average value of the distance D2 on the discharge side with respect to the straight line L4. Therefore, even if an eccentric assembly is performed in which the cylinder 30 is eccentric to the suction side with respect to the bearing center of the shaft 8, the radial direction between the outer peripheral surface of the roller 41 and the peripheral wall surface of the compression chamber 31 of the cylinder 30 on the suction side. The gap d can be reduced and the volumetric efficiency can be improved.

  In the compressor 1 of the present embodiment, laser processing is performed on a part of the outer peripheral surface of the roller 41. Therefore, the distance D2 from the center O3 of the inner peripheral surface of the roller 41 to the outer peripheral surface of the roller 41 is easily continuous with respect to the angle around the center O3 by performing laser processing on the outer peripheral surface of the roller 41 and expanding it. Can be processed into a shape that changes with time.

  Further, in the compressor 1 of the present embodiment, the cross-section of the compression chamber 31 of the cylinder 30 in the plane orthogonal to the straight line L1 extending in the extending direction of the blade accommodating portion 33 has an average value of the area on the suction side from the straight line L1. , Smaller than the average value of the area on the discharge side than the straight line L1. Therefore, not only the piston 40 side but also the cylinder 30 side is shaped so as to reduce the radial gap d between the outer peripheral surface of the roller 41 and the peripheral wall surface of the compression chamber 31 on the suction side. Since the amount of machining can be reduced, variations in machining can be suppressed.

  Furthermore, in the compressor 1 of the present embodiment, laser processing is performed on a part of the wall surface that defines the compression chamber 31 of the cylinder 30. Therefore, the wall surface defining the compression chamber 31 of the cylinder 30 is subjected to laser processing and expanded so that the average value of the area on the suction side with respect to the straight line L1 is easily the average value of the area on the discharge side with respect to the straight line L1. It can be processed into a shape that becomes smaller.

  As mentioned above, although embodiment of this invention was described based on drawing, it should be thought that a specific structure is not limited to these embodiment. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and further includes all modifications within the meaning and scope equivalent to the scope of claims for patent.

  For example, in the above-described embodiment, the cross section of the compression chamber 31 of the cylinder 30 in the plane orthogonal to the straight line L1 extending in the extending direction of the blade accommodating portion 33 has an average value of the area on the suction side from the straight line L1. However, the shape of the cylinder 30 is not limited to this, and the inner peripheral surface of the cylinder 30 is equidistant from the center of the inner peripheral surface of the cylinder 30. It may be a conventional shape. Thus, when the cylinder 30 has a conventional shape and only the shape of the outer peripheral surface of the roller 41 is deformed from the conventional shape to the shape shown in FIG. 5 (Modification 1), the peripheral wall surface of the compression chamber 31 and the roller As shown by a one-dot chain line in FIG. 7, the radial clearance d between the outer peripheral surface 41 and the outer peripheral surface 41 is the largest when the crank angle θ1 is 100 °, and is about 0.045 mm, and the crank angle θ1 is 270 °. It is the smallest in the part which becomes and is about 0.01 mm. That is, the maximum value of the radial gap d in this case is larger than the maximum value (0.03 mm) of the radial gap d in the above-described embodiment, but the cylinders and rollers have the conventional shapes. Is sufficiently smaller than the maximum value (0.06 mm) of the radial gap d.

  Further, by making the processing amount of the outer peripheral surface of the roller 41 larger than that in the above-described embodiment, even if the inner peripheral surface of the cylinder 30 has a conventional shape that is equidistant from the center of the inner peripheral surface of the cylinder 30, It is also possible to obtain a radial gap d similar to that of the embodiment (Modification 2 shown in FIG. 8).

  Further, the crank angle θ1 at which the radial gap d is the smallest is not limited to 270 °. For example, in a setting where the radial gap d is the smallest at 300 °, the same processing as in the embodiment is applied to the outer peripheral surface of the roller 41 and the inner peripheral surface of the cylinder 30 to compare with the conventional shape shown in FIG. Thus, a small radial gap d can be realized at both the crank angle where the differential pressure between the suction side and the discharge side of the compression chamber 31 is large and the crank angle where the differential pressure is small (Modification 3 shown in FIG. 9).

  In the above-described embodiment, a part of the outer peripheral surface of the roller is subjected to laser processing, and the portion of the outer peripheral surface of the roller 41 subjected to laser processing is a distance from the center O3 of the inner peripheral surface of the roller 41. Although the case where D2 continuously changes with respect to the angle around the center O3 has been described, the present invention is not limited to this. That is, the entire outer peripheral surface of the roller 41 is laser processed, and the distance D2 from the center O3 of the inner peripheral surface of the roller 41 is continuous with respect to the angle around the center O3 in the entire outer peripheral surface of the roller 41. (Modification 4 shown in FIG. 10: The alternate long and short dash line in FIG. 10 indicates that the entire outer peripheral surface of the roller 41 is subjected to laser processing, and the inner peripheral surface of the cylinder 30 shows a conventional shape). Further, by performing processing other than laser processing such as cutting, the distance D2 from the center O3 of the inner peripheral surface of the roller 41 to the outer peripheral surface of the roller 41 continuously changes with respect to the angle around the center O3. It is good also as such a shape.

  Further, in the above-described embodiment, the case where laser processing is performed on a part of the wall surface that defines the compression chamber 31 of the cylinder 30 has been described. However, laser processing is performed on the entire wall surface that defines the compression chamber 31. (Modification 4 shown in FIG. 10: The broken line in the figure shows a case where the outer peripheral surface of the roller 41 and the entire wall surface defining the compression chamber 31 of the cylinder 30 are subjected to laser processing). Moreover, processes other than laser processing, such as cutting, may be performed.

  Furthermore, in the above-mentioned embodiment, although applied to the 1-cylinder type rotary compressor, you may apply to a 2-cylinder type rotary compressor.

  If the present invention is used, the gap between the outer peripheral surface of the roller and the peripheral wall surface of the compression chamber on the suction side can be reduced, and the volumetric efficiency can be increased.

1 Compressor 8 Shaft (drive shaft)
8a Eccentric part 30 Cylinder 31 Compression chamber 33 Blade housing part 40 Piston 41 Roller 42 Blade

Claims (4)

A cylinder having a compression chamber and a blade accommodating portion communicating with the compression chamber;
A piston disposed inside the compression chamber and the blade housing;
A drive shaft having an eccentric part,
The piston is disposed in the compression chamber and an annular roller attached to the eccentric portion of the drive shaft, and is disposed so as to extend from the outer peripheral surface of the roller and to advance and retreat with respect to the blade accommodating portion. A blade,
The cylinder is eccentric to the suction side with respect to the bearing center of the drive shaft;
At least a part of the outer peripheral surface of the roller is sucked more than a first straight line extending in the extending direction of the blade, with the distance from the center of the inner peripheral surface of the roller continuously changing with respect to the angle around the center. The compressor is characterized in that an average value of the distance on the side is longer than an average value of the distance on the discharge side than the first straight line.   The compressor according to claim 1, wherein at least a part of the outer peripheral surface of the roller is subjected to laser processing.   The cross section of the compression chamber of the cylinder in a plane perpendicular to the second straight line extending in the extending direction of the blade accommodating chamber is such that the average value of the area on the suction side with respect to the second straight line is higher than that of the second straight line. The compressor according to claim 1, wherein the compressor is smaller than an average value of the area on the side.   The compressor according to claim 3, wherein at least a part of a wall surface defining the compression chamber of the cylinder is subjected to laser processing.

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