JP4929686B2 - Machining method of annular piston for rotary fluid machine - Google Patents

Description

  The present invention relates to a method for processing an annular piston for a rotary fluid machine, in which an annular piston main body is integrally erected on a piston side end plate, and a cylindrical recess is provided in a part of the annular piston main body. .

  Conventionally, there has been known a rotary fluid machine in which a cylinder having an annular cylinder chamber and an annular piston disposed in the cylinder chamber are relatively eccentrically rotated (see, for example, Patent Document 1). In this rotary fluid machine, an annular cylinder chamber is divided into an inner cylinder chamber and an outer cylinder chamber by an annular piston, and each is a fluid chamber for compressing or expanding fluid. Such a rotary fluid machine is used as, for example, a compressor that compresses refrigerant flowing through a refrigerant circuit.

  The cylinder includes an outer cylinder portion, an inner cylinder portion, and a cylinder side end plate connecting both cylinder portions, and the cylinder side end plate is provided on one end side in the axial direction of the cylinder chamber, and the outer cylinder portion and the inner cylinder portion The cylinder chamber is formed between the two.

  The annular piston substantially touches the inner peripheral surface of the outer cylinder part at one point on the outer peripheral surface ("substantially contact" means that there is a fine gap that can form an oil film. Eccentric rotational motion while maintaining a state where one point of the inner peripheral surface is substantially in contact with the outer peripheral surface of the inner cylinder at a position 180 degrees out of phase with the refrigerant leakage in the gap. An annular piston main body configured to perform this operation, and a piston side end plate integrated with the annular piston main body, and the piston side end plate is spaced from the cylinder side end plate on the other end side in the axial direction of the cylinder chamber. They are arranged so as to face each other. An outer cylinder chamber is formed outside the annular piston and an inner cylinder chamber is formed inside the annular piston between the cylinder side end plate and the piston side end plate.

As this type of fluid machine, there is a fluid machine that includes a blade that divides a cylinder chamber into a high pressure side and a low pressure side, and the blade and an annular piston are connected so as to be able to swing (see, for example, Patent Document 2). In the fluid machine of Patent Document 2, a swing bush is provided as a member for swingably connecting the blade and the annular piston. This oscillating bush is a member arranged on both sides of the blade, and is slidable in the surface direction of the blade with respect to the blade, while the outer peripheral surface has a cylindrical shape. The annular piston is configured to be swingable with respect to the center. The swing bush is mounted in a swing bush holding recess (cylindrical recess) formed in the annular piston.
Japanese Utility Model Publication No. 60-90580 Japanese Utility Model Publication No. 51-23371

  By the way, in order to cut the inner peripheral surface and the outer peripheral surface of the annular piston, for example, it is possible to use a processing tool having a relatively large diameter (for example, an end mill). Since the diameter is smaller than the diameter of the outer peripheral surface and inner peripheral surface of the annular piston, it has been necessary to perform processing using a processing tool having a small diameter.

  In that case, after processing the inner peripheral side and the outer peripheral side of the annular piston body, the processing tool is retracted from the annular piston as the workpiece, and the processing tool is for processing the inner peripheral surface and outer peripheral surface of the annular piston. Therefore, it is necessary to replace the swing bushing holding recess with the one for processing the recess, and the processing process becomes complicated.

  This invention is made | formed in view of this point, The objective is to prevent that the manufacturing process of the internal peripheral surface of a cyclic | annular piston, an outer peripheral surface, and a rocking | fluctuation bush holding | maintenance recessed part becomes complicated.

The first invention comprises an annular piston (45) having a piston side end plate (45b) and an annular piston main body (45a), and a cylinder (40) having an outer cylinder part (40a) and an inner cylinder part (40b). Provided, the outer peripheral surface of the annular piston main body (45a) is smaller in diameter than the inner peripheral surface of the outer cylinder (40a), and the inner peripheral surface of the annular piston main body (45a) is smaller than the outer peripheral surface of the inner cylinder (40b). Is formed with a large diameter, and the annular piston (45) and the cylinder (40) are relatively eccentrically rotated. The base end of the annular piston body (45a) is connected to the piston side end plate (45b) to integrally form the annular piston (45), and the center of the annular piston body (45a) A cylindrical recess (45 c) is formed so that the cylindrical recess (45c) partially cuts off the wall surface of the annular piston body (45a), and the annular piston body (45a) is partially cut off from the ring. The processing method of the said annular piston (45) formed in C shape is a premise.

In the processing method of the first invention, the diameter 2r is smaller than the minimum width b of the cylindrical recess (45c) and the diameter 2R of the inner peripheral surface (45j) of the cylindrical recess (45c). A first machining step (P1) for machining one of the inner circumferential surface (45d) and the outer circumferential surface (45e) of the annular piston body (45a) using a machining tool (60) having a small diameter 2r, and a cylindrical recess The second machining step (P2) for machining the inner circumferential surface (45j) of (45c) and the third machining for machining the other of the inner circumferential surface (45d) or the outer circumferential surface (45e) of the annular piston main body (45a). Step (P3) is performed in order, and when the first processing step (P1), the second processing step (P2), and the third processing step (P3) are performed, the axial position of the processing tool (60) is set as an annular piston. (45) As a state fixed to the piston side end plate (45b), the annular piston body (45a) side plane (45g) (45h) (45i) Characterized in that processing to the annular piston body inner peripheral side of the portion (45 g), the outer peripheral portion of (45a) (45h), and a cylindrical recess (45 c) in part of (45i) is flush It is said.

  The “processing” referred to in the present invention includes cutting and polishing.

The second invention is a processing method based on the same premise as in the first invention, wherein the diameter 2r is smaller than the minimum width b of the cylindrical recess (45c) and the inner peripheral surface (45j) of the cylindrical recess (45c). The first machining step (P1) for machining one of the inner peripheral surface (45d) and the outer peripheral surface (45e) of the annular piston body (45a) using a processing tool (60) having a diameter 2r smaller than the diameter 2R of And a second machining step (P2) in which the inner peripheral surface (45j) of the cylindrical recess (45c) is divided into a first half and a second half, and the inner peripheral surface (45d) of the annular piston body (45a) or A third machining step (P3) for machining the other outer peripheral surface (45e), a first half of the second machining step, a first machining step, a second half of the second machining step, and a third machining step. In order to perform the first machining step (P1), the second machining step (P2), and the third machining step (P3), the axial position of the machining tool (60) is changed. As the state fixed to the piston (45), the plane (45g) (45h) (45i) on the annular piston body (45a) side of the piston side end plate (45b) is connected to the annular piston body (45a). The inner circumferential portion (45g), the outer circumferential portion (45h), and the portion (45i) in the cylindrical recess (45c) are processed to be in the same plane .

The third invention is a processing method based on the same assumption as the first invention, wherein the diameter 2r is smaller than the minimum width b of the cylindrical recess (45c), and the inner peripheral surface of the cylindrical recess (45c). A first machining step of machining one of the inner circumferential surface (45d) and the outer circumferential surface (45e) of the annular piston body (45a) using a machining tool (60) having a diameter 2r smaller than the diameter 2R of (45j) ( P1), a second machining step (P2) in which the inner circumferential surface (45j) of the cylindrical recess (45c) is divided into the first half and the second half, and the inner circumferential surface (45d) of the annular piston body (45a) ) Or the third processing step (P3) for processing the other of the outer peripheral surface (45e), the first processing step, the first half of the second processing step, the third processing step, and the second processing step. The second half is sequentially performed, and when the first machining step (P1), the second machining step (P2), and the third machining step (P3) are performed, the axial position of the machining tool (60) The plane (45g) (45h) (45i) on the annular piston main body (45a) side of the piston side end plate (45b) is fixed to the annular piston main body (45a). ), The inner peripheral part (45g), the outer peripheral part (45h), and the part (45i) in the cylindrical recess (45c) are processed in the same plane .

In these first to third inventions, since the diameter 2r of the machining tool is smaller than the minimum width b of the cylindrical recess (45c), when moving from the first machining step (P1) to the second machining step (P2) When moving from the second processing step (P2) to the third processing step (P3) (in the second and third inventions, when moving from the second processing step (P2) to the first processing step (P1) In some cases, the third machining step (P3) may move to the second machining step (P2)), and the machining tool (60) is moved to the inner circumferential surface (45d) and outer circumferential surface (45e) of the annular piston body (45a). The above three machining steps (P1, P2, P3) can be performed continuously without escaping in the axial direction. Therefore, when processing the inner peripheral surface (45d) and the outer peripheral surface (45e) of the annular piston main body (45a), there is no need to temporarily retract the processing tool (60) from the annular piston (45). And the operation | work which replaces a processing tool (60) during a manufacturing process becomes unnecessary, and a processing process becomes simple .

In each of the above inventions, the axial position of the machining tool (60) is fixed to the annular piston (45), and the plane (45g) on the annular piston body (45a) side of the piston side end plate (45b) ) (45h) (45i), the inner peripheral part (45g) of the annular piston body (45a), the outer peripheral part (45h), and the part (45i) in the swinging bush holding recess (45c) Are processed so as to be on the same plane.

According to a fourth invention, in any one of the first to third inventions, a machining tool (60) having a diameter 2r larger than the radius R of the cylindrical recess (45c) is used as the machining tool (60). It is a feature.

If the diameter 2r of the machining tool (60) is smaller than the radius R of the cylindrical recess (45c), the uncut portion is generated only by turning the machining tool (60) once in the cylindrical recess (45c). Therefore, it is necessary to turn the machining tool (60) several times while changing the turning radius. In the fourth aspect of the invention , the diameter 2r of the machining tool (60) is larger than the radius R of the cylindrical recess (45c). Since the dimensions are set, the machining of the cylindrical recess (45c) is completed only by rotating the machining tool (60) once in the cylindrical recess (45c).

  Further, when the diameter 2r of the processing tool (60) is made smaller than the radius R of the cylindrical recess (45c), the processing tool (60) becomes thin and the strength becomes weak. However, in the present invention, the machining tool (60) has a diameter 2r larger than the radius R of the cylindrical recess (45c). By doing so, the deflection of the machining tool (60) can be suppressed.

  According to the first to third inventions, since each processing step (P1, P2, P3) can be performed continuously, the inner peripheral surface (45d) and the outer peripheral surface (45e) of the annular piston body (45a) Compared with the method of machining the swinging bush holding recess (45c) with another machining tool (60) having a different diameter, the process can be simplified, and as a result, the machining time can be shortened.

In addition, since the machining tool (60) is not moved in the axial direction when the first machining process (P1), the second machining process (P2), and the third machining process (P3) are performed, the piston side end plate ( The flat surface (45g) (45h) (45i) on the annular piston body (45a) side in 45b) has an inner peripheral part (45g) and an outer peripheral part (45h) of the annular piston body (45a). And a step (45i) in the swinging bush holding recess (45c) does not cause a step. If the flat part (45i) in the rocking bush holding recess (45c) is lower than the flat part (45g) (45h) on the inner and outer circumferences of the annular piston body (45a), refrigerant leakage is likely to occur, and conversely high. However, in the present invention, such a problem does not occur.

According to the fourth invention , since the diameter of the machining tool (60) is larger than the radius of the cylindrical recess (45c), the machining of the cylindrical recess (45c) by the machining tool (60) is possible. It becomes easy and the processing accuracy of the cylindrical recess (45c) can be increased.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  First, a rotary fluid machine including an annular piston to which a processing method according to the present invention is applied will be described. The rotary fluid machine shown in FIG. 1 is a rotary compressor (10) that compresses fluid in a cylinder chamber (41, 42). The rotary compressor (10) is provided, for example, in a refrigerant circuit of an air conditioner, and is used to compress the refrigerant sucked from the evaporator and discharge it to the condenser.

  As shown in FIG. 1, the rotary compressor (10) includes a casing (15) which is a vertically long and cylindrical sealed container. Inside the casing (15), the compression mechanism (20) is disposed at a lower position, and the electric motor (30) is disposed at an upper position.

  The casing (15) is provided with a suction pipe (14) penetrating through the trunk and a discharge pipe (13) penetrating through the upper part. The suction pipe (14) is connected to the compression mechanism (20), and the discharge pipe (13) has an inlet opening in a space above the electric motor (30).

  Inside the casing (15), a crankshaft (33) extending in the vertical direction is provided as a rotating shaft. The crankshaft (33) includes a main shaft portion (33a) and an eccentric portion (33b). The eccentric part (33b) is provided at a lower position of the crankshaft (33), and is formed in a cylindrical shape having a larger diameter than the main shaft part (33a). The eccentric portion (33b) has an axis that is eccentric from the axis of the main shaft portion (33a) by a predetermined amount.

  The electric motor (30) includes a stator (31) and a rotor (32). The stator (31) is fixed to the inner peripheral surface of the body portion of the casing (15). The rotor (32) is disposed inside the stator (31) and connected to the main shaft portion (33a) of the crankshaft (33), and is configured to rotate together with the crankshaft (33).

  The compression mechanism (20) is configured in a state in which a rear head (37), a cylinder (40), and a front head (36) are stacked in order from the lower side. As shown in FIG. 2, an annular piston (45), a blade (46), and a swing bush (27) are accommodated in the cylinder (40). In the annular piston (45), the base end (lower end) of the annular piston main body (45a) is connected to the upper surface of the piston side end plate (45b) which is a flat plate portion of the rear head (37).

  The cylinder (40) includes an outer cylinder part (40a) and an inner cylinder part (40b). Both the outer cylinder part (40a) and the inner cylinder part (40b) are formed in an annular shape. The inner peripheral surface of the outer cylinder part (40a) and the outer peripheral surface of the inner cylinder part (40b) are cylindrical surfaces having the same center. An annular cylinder chamber (41, 42) is formed between the inner peripheral surface of the outer cylinder portion (40a) and the outer peripheral surface of the inner cylinder portion (40b).

  The outer cylinder part (40a) and the inner cylinder part (40b) are disposed below the end plate part (36b) of the front head (36) (see FIG. 1). The outer cylinder part (40a) and the inner cylinder part (40b) are coupled together by a cylinder side end plate (47). The cylinder side end plate (47) faces the cylinder chamber (41, 42) on the tip side (upper end side) of the annular piston (45) and faces the tip of the annular piston main body (45a). The rear head (37) faces the cylinder chamber (41, 42) on the tip side (lower side) of the outer cylinder part (40a) and the inner cylinder part (40b). It faces the tip of the cylinder (40b).

  The eccentric part (33b) of the crankshaft (33) is slidably fitted on the inner peripheral surface of the inner cylinder part (40b). In the rotary compressor (10) of the present embodiment, the annular piston (45) is fixed and the cylinder (40) performs an eccentric rotational motion, so that the annular piston (45) and the cylinder (40) are relatively moved. It is comprised so that an eccentric rotational motion may be carried out.

  The annular piston main body (45a) is formed in a C shape in which a part of the annular ring is divided. The annular piston body (45a) has an outer peripheral surface that is smaller in diameter than the inner peripheral surface of the outer cylinder portion (40a), and an inner peripheral surface that is larger in diameter than the outer peripheral surface of the inner cylinder portion (40b). The annular piston (45) is housed in the cylinder chamber (41, 42) in an eccentric state with respect to the cylinder (40), and divides the cylinder chamber (41, 42) into an inner side and an outer side. An outer cylinder chamber (41) is formed between the outer peripheral surface of the annular piston main body (45a) and the inner peripheral surface of the outer cylinder (40a), and the inner peripheral surface and inner side of the annular piston main body (45a) are formed. An inner cylinder chamber (42) is formed between the outer peripheral surface of the cylinder part (40b).

  The annular piston (45) and the cylinder (40) are in a state where the outer peripheral surface of the annular piston main body (45a) and the inner peripheral surface of the outer cylinder (40a) are substantially in contact at one point (strictly in the micron order) In a state where the leakage of refrigerant in the gap is not a problem), the inner peripheral surface of the annular piston body (45a) and the inner cylinder (40b) Are substantially in contact with each other at one point.

  The blade (46) is inserted through the part where the annular piston (45) is divided, and the radial direction of the cylinder chamber (41, 42) from the inner peripheral surface of the outer cylinder portion (40a) to the outer peripheral surface of the inner cylinder portion (40b). It is provided so that it may extend. The blade (46) is fixed to the inner peripheral surface of the outer cylinder portion (40a) and the outer peripheral surface of the inner cylinder portion (40b). Thus, the blade (46) divides the cylinder chambers (41, 42) into a high pressure chamber (compression chamber) (41a, 42a) and a low pressure chamber (suction chamber) (41b, 42b).

  The oscillating bush (27) is formed in the oscillating bush holding recess (cylindrical recess: C-shaped opening from which a part of the ring is extracted) (45c) of the annular piston (45). The blade (46) is movably connected to each other. The cylindrical recess (45c) is a recess that cuts off a part of the wall surface of the annular piston body (45a), and is provided on a center line parallel to the center line of the annular piston body (45a). The swing bush (27) is disposed on the discharge side bush (27a) located on the high pressure chamber (41a, 42a) side with respect to the blade (46), and on the low pressure chamber (41b, 42b) side with respect to the blade (46). It is comprised from the suction side bush (27b) located. The discharge-side bush (27a) and the suction-side bush (27b) are both substantially semicircular in cross section and formed in the same shape, and are arranged so that the flat surfaces face each other. A space between the opposing flat surfaces of both bushes (27a, 27b) constitutes a blade groove (28). The blade (46) is inserted into the blade groove (28).

  The flat surfaces of the swing bushes (27a, 27b) (both side surfaces of the blade groove (28)) are substantially in surface contact with the blade (46). The arcuate outer peripheral surface of the swing bush (27a, 27b) is substantially in surface contact with the annular piston (45). The swing bush (27a, 27b) is configured such that the blade (46) advances and retreats in the blade groove (28) in the surface direction with the blade (46) sandwiched between the blade groove (28). . At the same time, the swing bushes (27a, 27b) are configured to swing integrally with the blade (46) with respect to the annular piston (45). Therefore, the swing bush (27) is configured such that the blade (46) and the annular piston (45) can swing relative to each other with the center point of the swing bush (27) as the swing center, and the blade (46) Is configured to be able to advance and retreat in the surface direction of the blade (46) with respect to the annular piston (45).

  In this embodiment, an example in which both bushes (27a, 27b) are separated from each other has been described. However, both bushes (27a, 27b) may be integrated with each other.

  A suction space (5) is formed outside the outer cylinder part (40a). In the suction space (5), the outlet end of the suction pipe (14) is opened. The outer cylinder portion (40a) is formed with a through hole (43) that communicates the suction space (5) and the low pressure chamber (41b) of the outer cylinder chamber (41), and the annular piston (45) has an outer cylinder chamber ( A through hole (44) is formed to communicate the low pressure chamber (41b) of 41) and the low pressure chamber (42b) of the inner cylinder chamber (42). These through holes (43, 44) constitute a suction port. Thus, the suction space (5) communicates with the low pressure chamber (41b) of the outer cylinder chamber (41) and also communicates with the low pressure chamber (42b) of the inner cylinder chamber (42).

  The rear head (37) is formed with an outer discharge passage (51) and an inner discharge passage (52). The outer discharge passage (51) has an inlet end that opens to the high-pressure chamber (41a) of the outer cylinder chamber (41), and an outlet end that opens to a discharge space (53) described later. The inner discharge passage (52) has an inlet end opened to the high pressure chamber (42a) of the inner cylinder chamber (42) and an outlet end opened to the discharge space (53). A reed valve (not shown) for opening and closing the outlet end of each discharge passage (51, 52) is provided on the lower surface of the rear head (37).

  A muffler (23) is attached to the lower side of the rear head (37). A discharge space (53) is formed between the rear head (37) and the muffler (23). A connection passage (57) that connects the discharge space (53) and the upper space of the compression mechanism (20) is formed at the outer edge of the front head (36) and the rear head (37).

  Bearing parts (36a, 37a) for supporting the crankshaft (33) are formed on the front head (36) and the rear head (37), respectively. The crankshaft (33) penetrates the compression mechanism (20) in the vertical direction and is held by the casing (15) via the front head (36) and the rear head (37).

  An oil supply pump (34) is provided at the lower end of the crankshaft (33). The oil supply pump (34) is connected to an oil supply path (not shown) extending along the axis of the crankshaft (33) and communicating with the compression mechanism (20). The oil supply pump (34) is configured to supply the lubricating oil stored at the bottom in the casing (15) to the sliding portion of the compression mechanism (20) through the oil supply passage.

  In the above configuration, when the operation of the rotary compressor (10) is started and the crankshaft (33) is rotated, the outer cylinder portion (40a) and the inner cylinder portion (40b) are oriented in the direction of the blade groove (28). While moving forwards and backwards (in the radial direction of the cylinder chamber (41, 42)), it swings with the center point of the swing bush (27) as the swing center. By this swinging motion, the cylinder (40) rotates (revolves) while being eccentric with respect to the crankshaft (33) (see FIGS. 3A to 3D).

-Driving action-
Next, the operation of the rotary compressor (10) will be described with reference to FIG. FIG. 3 is a diagram showing the operation of the compression mechanism (20) as a state change accompanying the rotation of the crankshaft (33).

  When the electric motor (30) is started, the rotation of the rotor (32) is transmitted to the outer cylinder part (40a) and the inner cylinder part (40b) of the compression mechanism (20) via the crankshaft (33). As a result, the blade (46) reciprocates (advances and retracts) between the swing bushes (27a, 27b), and the blade (46) and the swing bushes (27a, 27b) become an integral unit. Oscillates with respect to the annular piston (45). The outer cylinder portion (40a) and the inner cylinder portion (40b) revolve while swinging with respect to the annular piston (45), and the compression mechanism (20) performs a predetermined compression operation.

  Here, in the outer cylinder chamber (41), the cylinder (40) revolves clockwise from the state shown in FIG. 3C (the state where the low pressure chamber (41b) becomes almost the minimum volume), thereby The refrigerant is sucked into the low pressure chamber (41b) from the through hole (43) of the cylinder portion (40a). When the cylinder (40) revolves in the order of (D), (A), and (B) in FIG. 3 and enters the state of (C) in FIG. 3 again, the refrigerant is sucked into the low pressure chamber (41b). Complete.

  Here, the low-pressure chamber (41b) becomes a high-pressure chamber (41a) in which the refrigerant is compressed in the process of shifting from (C) to (D) in FIG. 3, while the new low-pressure chamber (41b) is separated from the blade (46). A chamber (41b) is formed. When the cylinder (40) further rotates in this state, the suction of the refrigerant is repeated in the newly formed low pressure chamber (41b), while the volume of the high pressure chamber (41a) is reduced, and the refrigerant in the high pressure chamber (41a) is reduced. Is compressed. When the pressure in the high pressure chamber (41a) reaches a predetermined value, the reed valve is opened and the high pressure refrigerant compressed in the outer cylinder chamber (41) passes through the outer discharge passage (51) and passes through the discharge space ( 53).

  In the inner cylinder chamber (42), the cylinder (40) revolves clockwise from the state shown in FIG. 3A (the state in which the volume of the low pressure chamber (42b) is substantially minimized), so that the outer cylinder portion The refrigerant is sucked into the low pressure chamber (42b) from the through hole (43) of (40a) and the through hole (44) of the annular piston (45). Then, when the cylinder (40) revolves in the order of (B), (C) and (D) in FIG. 3 and enters the state of FIG. 3 (A) again, the suction of the refrigerant into the low pressure chamber (42b) is completed. To do.

  Here, the low-pressure chamber (42b) becomes a high-pressure chamber (42a) in which the refrigerant is compressed in the process of shifting from (A) to (B) in FIG. 3, while the new low-pressure chamber (42b) is separated from the blade (46). A chamber (42b) is formed. When the cylinder (40) further rotates in this state, the suction of the refrigerant is repeated in the newly formed low pressure chamber (42b), while the volume of the high pressure chamber (42a) is reduced, and the refrigerant in the high pressure chamber (42a) is reduced. Is compressed. When the pressure in the high pressure chamber (42a) reaches a predetermined value, the reed valve is opened and the high pressure refrigerant compressed in the inner cylinder chamber (42) passes through the inner discharge passage (52) and passes through the discharge space ( 53).

  The refrigerant discharged into the discharge space (53) flows through the connection passage (57), flows into the space above the compression mechanism (20), and then core cut (not shown) formed on the outer periphery of the stator (31). ) And the gap between the stator (31) and the rotor (32) flows into the space above the electric motor (30) and is discharged from the discharge pipe (13).

-Machining method of annular piston-
As described above, the annular piston (45) has the piston-side end plate (45b) with the annular piston main body (45a) standing integrally therewith, and the swing piston is held on a part of the annular piston main body (45a). A recess (45c) is provided. Hereinafter, the processing method of this annular piston (45) is demonstrated using FIG.4 and FIG.5.

  FIG. 4A is a plan view showing a state before the annular piston 45 is processed (material state), and FIG. 4B shows a state after the annular piston 45 is processed (finished part state). FIG. 4C is a plan view of FIG. 4B.

  When the material of the annular piston (45) is a casting, the processing method of the present invention is applied after rough processing. In order to leave a rough machining allowance, the material is produced with dimensions that are about 2 to 3 mm larger than the dimensions during finishing. In addition, the material of the annular piston (45) can be a material formed by a near net shape using sintered iron or the like (molded in a shape as close as possible to the shape of the finished part). In some cases, finishing is performed directly without roughing.

  When roughing is performed, locations where machining accuracy is required (for example, the inner peripheral surface (45j) of the swinging bush retaining recess (45c), the bearing hole (37b) of the bearing portion (37a), and the annular piston body (45a) Inner circumferential surface (45d), outer circumferential surface (45e) of annular piston body (45a), tip surface (45f) of annular piston body (45a), annular piston body (45a) on piston side end plate (45b) Since the side flat surface (45g) (45h) (45i), etc.) is finished, cutting is performed so that the finishing allowance (about 0.1 mm) is taken into account from the final dimension. A portion where accuracy is not required (for example, the back surface (45k) of the piston side end plate (45b)) is not subjected to the finishing process, and the processing is finished in the roughing process.

  Next, finishing is performed. Here, the inner and outer peripheral surfaces (45d, 45e) of the annular piston body (45a), the swinging bush retaining recess (45c), and the plane (45g) on the annular piston body (45a) side of the piston side end plate (45b) (45h) and (45i) will be described, and the description of the finish processing of the bearing hole (37b) and the tip surface (45f) of the annular piston body (45a) will be omitted.

First, in the processing method of this embodiment, in FIG. 5A, as an end mill (60) as a processing tool, the diameter 2r is smaller than the minimum width b of the swinging bush holding recess (45c), and the swinging bush is used. The holding recess (45c) having a diameter 2r smaller than the diameter 2R of the inner peripheral surface (45j) is used. The diameter 2r of the end mill (60) is larger than the radius R of the swinging bush holding recess (45c). That is, in this embodiment, the relationship between r, R, and b is
2r <b (1)
r <R (2)
2r> R (3)
Use an end mill (60) that satisfies the following relationship.

  Then, a first machining step (P1) for cutting one of the inner circumferential surface (45d) of the annular piston main body (45a) or the outer circumferential surface (45e) of the annular piston main body (45a), and a swinging bush holding recess The second machining step (P2) for cutting the inner circumferential surface (45j) of (45c) and the outer circumferential surface (45e) of the inner circumferential surface (45d) of the annular piston body (45a) or the annular piston body (45a). ) And the third machining step (P3) for cutting the other. In the example shown in FIG. 5B, the inner peripheral side of the annular piston main body (45a) is processed in the first processing step (P1), and the annular piston main body (45a) is processed in the third processing step (P3). The outer peripheral side is processed, but conversely, the outer peripheral side of the annular piston main body (45a) is processed in the first processing step (P1), and the annular piston main body (45a) is processed in the third processing step (P3). You may make it process the inner peripheral side of.

  Moreover, as a process which divides the internal peripheral surface (45j) of a cylindrical recessed part (45c) into a front half part and a latter half part and processes a 2nd process process, the first half part of a 2nd process step, a 1st process step, The second half of the second machining step and the third machining step may be performed in order, or the first machining step, the first half of the second machining step, the third machining step, and the second machining step. The latter half of the above may be performed in order. Note that the “first half” and “second half” of the second machining step may be any step in which the inner peripheral surface (45j) of the cylindrical recess (45c) is machined approximately half by half, and the second machining step is completely completed. There is no need to bisect and process.

  At the time of the above processing, the axial position of the end mill (60) is fixed to the annular piston (45), and the plane (45g) on the annular piston body (45a) side of the piston side end plate (45b) (45h) and (45i) are divided into an inner peripheral part (45g), an outer peripheral part (45h), and a part (45i) in the swinging bush holding recess (45c) of the annular piston body (45a). Cutting to be in the same plane.

  In this case, since the diameter 2r is smaller than the minimum width b of the swinging bush holding recess (45c), when moving from the first machining step (P1) to the second machining step (P2), the second machining step (P2) Without moving the end mill (60) in the axial direction from the machining position of the inner peripheral surface (45d) or outer peripheral surface (45e) of the annular piston main body (45a) when moving from to the third machining step (P3) The above three processing steps can be performed continuously. And the plane (45g) (45h) (45i) on the annular piston body (45a) side of the piston side end plate (45b) is the inner circumferential part (45g) of the annular piston body (45a), the outer circumferential side The portion (45h) and the portion (45i) in the swinging bush holding recess (45c) are finished to be flush with each other.

-Effect of the embodiment-
According to the present embodiment, the first machining step (P1), the second machining step (P2), and the third machining step (P3) can be performed continuously, so that the inner peripheral surface (45d) of the annular piston body (45a) ) And the outer peripheral surface (45e) and the oscillating bush holding recess (45c) can be simplified as compared with a method of processing with another end mill (60) having a different diameter, and as a result, the processing time can be shortened.

  Further, if the diameter 2r of the end mill (60) is smaller than the radius R of the swinging bush holding recess (45c), the end mill (60) is simply turned around in the swinging bush holding recess (45c). Since uncut parts are left, it is necessary to turn the end mill (60) several times while changing the turning radius. In this embodiment, the diameter 2r of the end mill (60) is made larger than the radius R of the swinging bush holding recess (45c). Therefore, the machining of the swinging bush holding recess (45c) is completed only by rotating the end mill (60) once in the swinging bush holding recess (45c).

  Further, when the diameter 2r of the end mill (60) is made smaller than the radius R of the swinging bush holding recess (45c), the strength of the end mill (60) becomes weak, so that the end mill (60) is bent during processing. In this embodiment, the diameter 2r of the end mill (60) is larger than the radius R of the swinging bush holding recess (45c), although the processing accuracy of the swinging bush holding recess (45c) may not be sufficiently obtained. By doing so, it is possible to suppress the bending of the end mill (60) and improve the processing accuracy of the swinging bush holding recess (45c).

  In the present embodiment, the end mill (60) is not moved in the axial direction when performing the first processing step (P1), the second processing step (P2), and the third processing step (P3). The plane (45g) (45h) (45i) on the annular piston main body (45a) side of the piston side end plate (45b) has an inner peripheral portion (45g) of the annular piston main body (45a) and an outer peripheral side. There is no step between the portion (45h) and the portion (45i) in the swinging bush holding recess (45c). If the flat part (45i) in the rocking bush holding recess (45c) is lower than the flat part (45g) (45h) on the inner and outer circumferences of the annular piston body (45a), refrigerant leakage is likely to occur, and conversely high. However, in this embodiment, such a problem does not occur.

  The piston side end plate (45b) has an outer peripheral portion (45h) on the annular piston main body (45a) side that is at least a portion in sliding contact with the outer cylinder portion (40a) and an inner peripheral portion (45g). It only needs to be processed in the same plane as the portion (45i) in the bush holding recess (45c), and the entire outer peripheral portion (45h) is not necessarily divided into the inner peripheral portion (45g) and the swinging bush holding recess (45c). It is not necessary to process it in the same plane as the part (45i) in).

<< Other Embodiments >>
About the said embodiment, it is good also as the following structures.

  For example, in the rotary compressor of the above embodiment, the annular piston (45) is the fixed side and the cylinder (40) is the movable side, but conversely, the cylinder (40) is the fixed side and the annular piston (45) is It is good also as a movable side.

  Further, the rotary fluid machine (10) having the annular piston manufactured by the processing method of the present invention is not limited to the compressor, and may be a pump or an expander.

  Furthermore, in the said embodiment, although the processing method was cutting, it may be a polishing process.

  Further, the diameter 2r of the end mill (60) may be smaller than the radius R of the swinging bush holding recess (45c), but in this case, the end mill (60) is moved to the swinging bush holding recess (45c) as the second processing step. ), The machining of the rocking bush holding recess (45c) is not completed, and it is necessary to make several turns while changing the turning radius. Even in that case, as explained in the above embodiment, the second machining step is divided into the first half and the second half, the first half of the second machining step, the first machining step, the second half of the second machining step, The three processing steps may be performed in order, or the first processing step, the first half of the second processing step, the third processing step, and the second half of the second processing step may be performed in order. May be.

  In addition, the above embodiment is an essentially preferable illustration, Comprising: It does not intend restrict | limiting the range of this invention, its application thing, or its use.

  As described above, in the present invention, the piston-side end plate (45b) is provided with the annular piston main body (45a) so as to be integrally formed, and the swinging bush holding recess (45c) is formed in a part of the annular piston main body (45a). This is useful for the processing method of the annular piston (45) for the rotary fluid machine (10) provided with the (cylindrical recess).

It is a longitudinal section showing an embodiment of a rotary compressor provided with an annular piston to which a processing method concerning the present invention is applied. It is a cross-sectional view of the compression mechanism in the rotary compressor of FIG. 3A to 3D are operation state diagrams of the compression mechanism. 4A is a plan view showing the annular piston before processing, FIG. 4B is a plan view showing the annular piston after processing, and FIG. 4C is a longitudinal sectional view of FIG. 4B. FIG. 5A is a diagram showing a dimensional relationship between the swinging bush holding concave portion of the annular piston and the end mill, and FIG. 5B is a diagram showing a machining process.

10 Rotary fluid machinery
45 Annular piston
45a Annular piston body
45b Piston end plate
45c Cylindrical recess
45d Inner circumferential surface of annular piston body
45e Outer peripheral surface of annular piston body
45g Inner peripheral part of the annular piston body
45h The outer peripheral part of the annular piston body
45i Part in cylindrical recess
45j Inner peripheral surface of cylindrical recess
60 End mill (machining tool)
P1 First machining process
P2 Second machining process
P3 Third machining process

Claims (4)

An annular piston main body comprising an annular piston (45) having a piston side end plate (45b) and an annular piston main body (45a), and a cylinder (40) having an outer cylinder (40a) and an inner cylinder (40b). The outer peripheral surface of (45a) is smaller in diameter than the inner peripheral surface of the outer cylinder portion (40a), and the inner peripheral surface of the annular piston main body portion (45a) is formed in a larger diameter than the outer peripheral surface of the inner cylinder portion (40b). , A method of processing the annular piston (45) for the rotary fluid machine (10) in which the annular piston (45) and the cylinder (40) are relatively eccentrically rotated.
And,
The base end of the annular piston body (45a) is connected to the piston side end plate (45b) to integrally form the annular piston (45), and a center line is formed on a part of the annular piston body (45a). Forms a cylindrical recess (45c) positioned parallel to the center line of the annular piston body (45a) so that the cylindrical recess (45c) partially cuts off the wall surface of the annular piston body (45a) The method for processing the annular piston (45), wherein the annular piston main body (45a) is formed into a C-shape with a part of the annular ring divided,
A machining tool (60) having a diameter 2r smaller than the minimum width b of the cylindrical recess (45c) and a diameter 2r smaller than the diameter 2R of the inner peripheral surface (45j) of the cylindrical recess (45c) is used.
A first machining step (P1) for machining one of the inner circumferential surface (45d) and the outer circumferential surface (45e) of the annular piston body (45a);
A second machining step (P2) for machining the inner peripheral surface (45j) of the cylindrical recess (45c);
A third machining step (P3) for machining the other of the inner circumferential surface (45d) or the outer circumferential surface (45e) of the annular piston body (45a),
When the first machining step (P1), the second machining step (P2), and the third machining step (P3) are performed, the axial position of the machining tool (60) is fixed to the annular piston (45). The plane (45g) (45h) (45i) on the annular piston body (45a) side of the piston side end plate (45b) is connected to the inner circumferential part (45g) of the annular piston body (45a), The processing method of the annular piston (45) for the rotary fluid machine (10), wherein the processing is performed so that the portion (45h) and the portion (45i) in the cylindrical recess (45c) are flush with each other. An annular piston main body comprising an annular piston (45) having a piston side end plate (45b) and an annular piston main body (45a), and a cylinder (40) having an outer cylinder (40a) and an inner cylinder (40b). The outer peripheral surface of (45a) is smaller in diameter than the inner peripheral surface of the outer cylinder portion (40a), and the inner peripheral surface of the annular piston main body portion (45a) is formed in a larger diameter than the outer peripheral surface of the inner cylinder portion (40b). , A method of processing the annular piston (45) for the rotary fluid machine (10) in which the annular piston (45) and the cylinder (40) are relatively eccentrically rotated.
And,
The base end of the annular piston body (45a) is connected to the piston side end plate (45b) to integrally form the annular piston (45), and a center line is formed on a part of the annular piston body (45a). Forms a cylindrical recess (45c) positioned parallel to the center line of the annular piston body (45a) so that the cylindrical recess (45c) partially cuts off the wall surface of the annular piston body (45a) The method for processing the annular piston (45), wherein the annular piston main body (45a) is formed into a C-shape with a part of the annular ring divided,
A machining tool (60) having a diameter 2r smaller than the minimum width b of the cylindrical recess (45c) and a diameter 2r smaller than the diameter 2R of the inner peripheral surface (45j) of the cylindrical recess (45c) is used.
A first machining step (P1) for machining one of the inner circumferential surface (45d) and the outer circumferential surface (45e) of the annular piston body (45a);
A second machining step (P2) in which the inner peripheral surface (45j) of the cylindrical recess (45c) is divided into a first half and a second half;
A third machining step (P3) for machining the other of the inner circumferential surface (45d) and the outer circumferential surface (45e) of the annular piston body (45a),
The first half of the second machining step, the first machining step, the second half of the second machining step, and the third machining step are sequentially performed.
When the first machining step (P1), the second machining step (P2), and the third machining step (P3) are performed, the axial position of the machining tool (60) is fixed to the annular piston (45). The plane (45g) (45h) (45i) on the annular piston body (45a) side of the piston side end plate (45b) is connected to the inner circumferential part (45g) of the annular piston body (45a), The processing method of the annular piston (45) for the rotary fluid machine (10), wherein the processing is performed so that the portion (45h) and the portion (45i) in the cylindrical recess (45c) are flush with each other. An annular piston main body comprising an annular piston (45) having a piston side end plate (45b) and an annular piston main body (45a), and a cylinder (40) having an outer cylinder (40a) and an inner cylinder (40b). The outer peripheral surface of (45a) is smaller in diameter than the inner peripheral surface of the outer cylinder portion (40a), and the inner peripheral surface of the annular piston main body portion (45a) is formed in a larger diameter than the outer peripheral surface of the inner cylinder portion (40b). , A method of processing the annular piston (45) for the rotary fluid machine (10) in which the annular piston (45) and the cylinder (40) are relatively eccentrically rotated.
And,
The base end of the annular piston body (45a) is connected to the piston side end plate (45b) to integrally form the annular piston (45), and a center line is formed on a part of the annular piston body (45a). Forms a cylindrical recess (45c) positioned parallel to the center line of the annular piston body (45a) so that the cylindrical recess (45c) partially cuts off the wall surface of the annular piston body (45a) The method for processing the annular piston (45), wherein the annular piston main body (45a) is formed into a C-shape with a part of the annular ring divided,
A machining tool (60) having a diameter 2r smaller than the minimum width b of the cylindrical recess (45c) and a diameter 2r smaller than the diameter 2R of the inner peripheral surface (45j) of the cylindrical recess (45c) is used.
A first machining step (P1) for machining one of the inner circumferential surface (45d) and the outer circumferential surface (45e) of the annular piston body (45a);
A second machining step (P2) in which the inner peripheral surface (45j) of the cylindrical recess (45c) is divided into a first half and a second half;
A third machining step (P3) for machining the other of the inner circumferential surface (45d) and the outer circumferential surface (45e) of the annular piston body (45a),
The first machining step, the first half of the second machining step, the third machining step, and the second half of the second machining step are performed in order,
When the first machining step (P1), the second machining step (P2), and the third machining step (P3) are performed, the axial position of the machining tool (60) is fixed to the annular piston (45). The plane (45g) (45h) (45i) on the annular piston body (45a) side of the piston side end plate (45b) is connected to the inner circumferential part (45g) of the annular piston body (45a), The processing method of the annular piston (45) for the rotary fluid machine (10), wherein the processing is performed so that the portion (45h) and the portion (45i) in the cylindrical recess (45c) are flush with each other. In any one of Claims 1-3,
Machining of an annular piston (45) for a rotary fluid machine (10) using a machining tool (60) having a diameter 2r larger than the radius R of the cylindrical recess (45c) as the machining tool (60) Method.

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