JP2001254680A - Method of manufacturing compressor piston - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a compressor piston capable of high-efficiently manufacturing the piston by preventing relative rotation between the piston and the support part of a supporting device during machining of the piston. SOLUTION: The neck parts of two piston materials 55 are interconnected in a direction of an axis S to mold a material 56 in an integrally formed shape. The material 56 is formed such that protrusion parts 59 each consisting of a supported part 57 and whirl-stops 58 are formed at the two end parts of the material 56. The whirl-stops 58 are symmetrically formed on both sides of the supported part 57 and a center hole 60 is formed at the central part of each protrusion part 59. During machining of the material 56, by inserting a center 61, serving as the support part of the supporting device, in the center hole 60, the material 56 is supported at the supporting device. Further, an engaging part 62 situated in the vicinity of the center 61 and the whirl-stop 58 are engaged with each other, resulting in prevention of relative rotation between the material 56 and the center 61.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing a piston of a compressor applied to, for example, a vehicle air conditioner.

[0002]

2. Description of the Related Art Compressors applied to vehicle air conditioners include:
There is a single-headed piston type variable displacement compressor as shown in FIG.

The front housing 11 is fixedly joined to a front end of a cylinder block 12 as a center housing. The rear housing 13 is joined and fixed to the rear end of the cylinder block 12 via a valve forming body 14.

[0004] The crank chamber 15 is provided in the front housing 1.
1 and a cylinder block 12. The drive shaft 16 is rotatably supported between the front housing 11 and the cylinder block 12 so as to pass through the crank chamber 15. Although not shown, drive shaft 1
Numeral 6 is operatively connected to a vehicle engine as an external drive source via a clutch mechanism such as an electromagnetic clutch.

[0005] The rotary support 17 is fixed to the drive shaft 16 in the crank chamber 15. The swash plate 18 as a cam plate is supported by the drive shaft 16 so as to be tiltable.
The swash plate 18 can rotate integrally with the drive shaft 16 via a hinge mechanism 19 and can tilt with respect to the drive shaft 16.

A plurality of cylinder bores 12a are formed around the axis L of the drive shaft 16 in the cylinder block 12 (only one is shown in the drawing). A plurality of single-headed pistons 20 are housed in each cylinder bore 12a. The piston 20 is moored to the swash plate 18 via a shoe 21. Therefore, the rotational motion of the drive shaft 16 is converted into a reciprocating motion of the piston 20 in the cylinder bore 12a via the swash plate 18 and the shoe 21.

[0007] The suction chamber 27 and the discharge chamber 28 are separately formed in the rear housing 13. Suction port 2
9, the suction valve 30, the discharge port 31, and the discharge valve 32 are formed on the valve forming body 14, respectively. The refrigerant gas in the suction chamber 27 is supplied to the cylinder bore 12 a through the suction port 29 and the suction valve 30 by the reciprocating operation of the piston 20.
Inhaled. The refrigerant gas sucked into the cylinder bore 12a is compressed to a predetermined pressure by the forward movement of the piston 20, and is discharged to the discharge chamber 28 via the discharge port 31 and the discharge valve 32.

The supply passage 33 is provided between the discharge chamber 28 and the crank chamber 1.
5 is connected. The bleed passage 34 connects the crank chamber 15 and the suction chamber 27. The capacity control valve 35 is provided in the air supply passage 33. The pressure-sensitive passage 36 connects the suction chamber 27 and the capacity control valve 35.

The displacement control valve 35 changes the opening of the air supply passage 33 by opening and closing the valve body 35b when the diaphragm 35a responds to the suction pressure introduced through the pressure sensing passage 36. When the degree of opening of the air supply passage 33 is changed, the amount of refrigerant gas discharged into the crank chamber 15 is changed, and the amount of refrigerant gas discharged to the suction chamber 27 via the bleed passage 34 is reduced. The pressure in the chamber 15 is changed. Therefore, the difference between the pressure in the crank chamber 15 and the pressure in the cylinder bore 12a via the piston 20 is changed, and the inclination angle of the swash plate 18 is changed. As a result, the stroke amount of the piston 20 is changed, and the discharge capacity is adjusted.

The connection structure between the piston 20 and the swash plate 18 via the shoes 21 allows the piston 20 to rotate around its own axis S. When the amount of rotation of the piston 20 is large, the vicinity of the neck 23 interferes with the rotating swash plate 18 and generates vibration and noise. For this reason, as shown in FIG. 9, a rotation restricting portion 23a is provided on the neck portion 23 of the piston 20.

As shown by a two-dot chain line in FIG. 9, the rotation of the piston 20 is restricted by the rotation restricting portion 23 a coming into contact with the inner peripheral surface 11 a of the front housing 11.
Further, the outer peripheral surface of the piston 20 and the rotation restricting portion 23a are provided on the outer peripheral surface and the rotation restricting portion 23a in order to suppress wear when sliding in the cylinder bore 12a.
Each has a wear-resistant coating layer.

As a method for manufacturing the above-mentioned single-headed piston, Japanese Unexamined Patent Publication No. 9-256952 discloses a method in which two pistons 40 are connected in the axial direction to form a piston 41 from an integrated material 41 as shown in FIG. A method of making is disclosed.

In this manufacturing method, the raw material 41 is formed by casting or forging, machined, formed with a coating layer covering the surface, polished, and then cut into individual pistons. At both ends of the raw material 41, supported portions 42 (holding portions) for supporting the raw material 41 with a supporting device at the time of machining are projected. The supported portion 42 is removed after machining (cutting) the piston. The coating layer is formed by spray painting.

This publication does not describe a specific method of supporting the raw material 41 during processing. However, generally, when machining a piston, for example, Japanese Patent Application Laid-Open No. 10-28106
As disclosed in Japanese Patent Laid-Open Publication No. 5 (1994), the material is supported at both ends thereof by a pair of support devices such as a center and a chuck.

In the apparatus disclosed in Japanese Patent Application Laid-Open No. H10-281065, a hole or a concave portion serving as a reference hole is provided as a supported portion instead of projecting a supported portion. Then, the material is supported by directly mounting the center of the support device in the hole or the concave portion.

As a method of forming a coating layer on the surface of the piston, there is a transfer method such as roll coating (for example, JP-A-11-201037) in addition to spray coating, and roll coating is superior. The roll coat is
A material is supported by a supporting device, and a surface on which a coating layer is to be formed is pressed against a transfer roll while rotating to form a coating layer.

[0017]

However, in the conventional method for manufacturing a piston, in the step of cutting the outer periphery of the piston, when the supported portions provided at both ends of the material are supported by the supporting device and rotated, If the cutting resistance is large, the material will rotate relative to the support device. As a result, it is not possible to increase the allowance for the outer shape processing, and it is necessary to perform the processing in a plurality of times, and there is a problem that productivity is reduced.

Also, when the coating layer is formed by roll coating, there is a problem that the material relatively rotates with the supporting device due to the resistance of the transfer roll to pressing. The present invention has been made in view of the problems existing in the prior art described above, and has as its object to prevent the relative rotation of the piston with the support portion of the support device during the processing of the piston, thereby efficiently manufacturing the piston. It is an object of the present invention to provide a method of manufacturing a compressor piston that can be used.

[0019]

According to a first aspect of the present invention, there is provided a method of manufacturing a piston of a compressor, comprising forming a material having a detent and a supported portion at at least one end. And supporting the material in a state in which the material is not relatively rotated with respect to the support portion by a support device having a support portion that supports the supported portion and an engaging portion that engages with the detent, and supports the material. And a step of processing while rotating.

According to the present invention, the rotation of the detent engages with the engagement portion, thereby preventing relative rotation between the material and the support portion during the processing of the material. According to a second aspect of the present invention, in the first aspect, the processing is a cutting process including a cutting process of the outer peripheral surface of the piston.

According to the present invention, in addition to the effect of the first aspect of the present invention, the machining allowance can be increased in the cutting process, and the productivity is improved. According to a third aspect of the present invention, in the first aspect, the processing is a coating process in which a coating material is applied to an outer peripheral surface of the piston by a transfer unit.

According to the present invention, in addition to the effect of the first aspect, the coating process can be performed efficiently.
According to a fourth aspect of the present invention, in the method for manufacturing a piston of a compressor in which two parts are joined while being rotated relative to each other, the end of the piston opposite to the joined part of at least one of the two parts is supported. A part and a detent are provided, and a supporting device having a supporting part that supports the supported part and an engaging part that engages with the detent is supported and rotated while the two parts are not relatively rotated. The gist of the present invention is to perform a processing including a welding process for joining the two parts.

According to the present invention, the rotation of the detent is engaged with the engagement portion, thereby preventing relative rotation between the component and the support portion. Therefore, the processing of the component can be performed efficiently.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is embodied in a method for manufacturing a piston of a compressor applied to a vehicle air conditioner will be described below.

(First Embodiment) First, the configuration of the piston 50 will be described in detail. As shown in FIG.
Is a cylindrical head 51 inserted into the cylinder bore.
And a neck 52 disposed outside the cylinder bore are integrally formed. The shoe seat 52 a is recessed inside the neck 52.

A pair of abutting portions 53 are provided at the neck 52 of the piston 50 so as to protrude forward and backward in the rotation direction of the swash plate. The contact surface 53a, which is an arc surface, is formed on the outer peripheral side of each contact portion 53. Each contact surface 53a faces the inner wall surface of the front housing in the crankcase. Both contact surfaces 5
3a is continuous via the connection surface 53b. Both contact surfaces 53a and connection surfaces 53b are present on the same circular arc surface.
The radius of curvature of the contact surface 53a and the connection surface 53b is
Is set to be larger than the radius of curvature of the outer peripheral surface 51a. Although not shown, the outer peripheral surface 51a, the connection surface 53b
Further, a coating layer for improving abrasion resistance is formed on the contact surface 53a.

Next, a method for manufacturing the piston 50 will be described.
As shown in FIG. 1 (a), a material 56 having a shape in which the necks of two piston materials 55 are connected together in the direction of the axis S to form a single body is formed by casting using aluminum or an aluminum alloy. In this case, the heads of the two piston blanks 55 are set to be coaxial with each other. Material 5
As shown in FIG. 1B, as shown in FIG. 1B, a projecting portion 59 forming a supported portion 57 and a detent 58 is formed at both ends of a material 56. The detents 58 are formed symmetrically on both sides of the supported portion 57, and a center hole 60 is formed at the center of each projection 59.

When the material 56 is processed, the center hole 60 is formed.
A center 61 (shown in FIG. 3) as a supporting portion of the supporting device
Is inserted, the material 56 is supported by the supporting device. The relative rotation between the material 56 and the center 61 is prevented by the engagement of the detent 58 with the engaging portion 62 (shown in FIG. 3) provided near the center 61.

First, mechanical processing such as external processing of the material 56 is performed. While rotating the material 56 supported by the support device, the outer peripheral surface 51a of the head of the piston by a lathe,
Mechanical processing is performed on the connection surface 53b, the contact surface 53a, the annular groove 63 as an oil reservoir, and the like.

Next, a coating layer is formed on the surface of the material 56 by roll coating. The material 56 is supported by the support device, and the rotation of the material 56 is prevented by the engagement between the rotation stopper 58 and the engagement portion 62. When the material 56 is urged toward the transfer roll by a spring or the like, the outer peripheral surface 51a, the connection surface 53b, and the contact surface 53a are pressed against the transfer roll. The coating material is transferred and applied to each surface by rotating the material 56 and the transfer roll.

More specifically, as shown in FIG. 3 (a), by using a head transfer roll 64 as the transfer roll, the outer peripheral surface 51a of the piston head 51 in contact therewith.
Only the coating layer is formed.

As shown in FIG. 3 (b), by using the transfer roll 65 for the contact portion as the transfer roll, a coating layer is formed on the connecting surface 53b and the contact surface 53a of the piston which comes into contact therewith. The fact that the arc centers of the connection surface 53b and the contact surface 53a are shifted with respect to the axis S of the piston, that is, the rotation center of the center 61 of the support device, depends on the connection surface 53b and the contact surface 53a. Material 5
6 corresponds to the contact portion transfer roll 65 by being able to follow and move by a spring.

In the material 56 on which the coating layer is formed, the outer peripheral surface 51a, the connection surface 53b and the contact surface 53a of the material 56 are polished in order to make the coating layer a predetermined thickness.

After the polishing process, the spherical surface of the shoe seat 52a is processed. Then, the material 56 is composed of two piston materials 5
5, the projection 59 is cut off, and the end face of the head 51 or the neck 52 of the piston material 55 is polished.

The present embodiment having the above configuration has the following effects. (1) The material 56 is supported by the center 61 of the support device, and the relative rotation is prevented by the engagement of the engaging portion 62 of the support device and the detent 58. Accordingly, it is possible to reliably prevent the blank 56 from idling with respect to the center 61 during processing.

(2) From the above effects, the machining allowance can be increased during cutting. In addition, roughing and finishing can be performed in a single process, thereby improving productivity.

(3) When the coating layer is formed by roll coating, the material 56 can be prevented from slipping on the transfer roll, and the thickness of the coating layer can be made uniform. (4) Since the detents 58 are provided at both ends of the material 56, the relative rotation (idling) between the material 56 and the center 61 of the support device is reliably prevented.

(5) Since the rotation stopper 58 is provided on the end face of the material 56, the structure of the engaging portion 62 on the supporting device side is simplified. (Second Embodiment) Next, a second embodiment will be described with reference to FIG. This embodiment is significantly different from the piston of the above embodiment in that the piston 70 is formed of two parts and the head is formed hollow. The same portions are denoted by the same reference numerals and description thereof will be omitted.

The piston 70 comprises a head part 71 and a neck part 72 housed in a cylinder bore. The head-side component 71 has a bottomed cylindrical shape with the bottom on the back side of the cylinder bore (on the valve / port forming body side). Neck part 7
2 is a lid 73 for closing the opening of the head-side component 71, and a lid 7
3 and a continuous neck portion 74.

The head of the piston comprises a bottomed cylindrical head body 75 and a lid 73. The two parts 71, 72
The supported portion 77 and the detent 78 are provided on the end surface opposite to the joining surface.
Are formed.

The lid 73 is formed in a disk shape centered on the axis S, and a ring-shaped fitting ridge 80 is provided at a joint with the head main body 75 so that the fitting ridge 80 has a head. The main body 75 is fitted to the inner peripheral surface 75b. The outer peripheral surface 73a of the lid 73 is formed to have substantially the same diameter as the outer peripheral surface 75a of the head main body.
Both parts 71 and 72 are formed of aluminum or aluminum alloy, respectively.

In this embodiment, both parts 71, 72
Are fixed to each other by friction welding. Both parts 7
The supporting members 1 and 72 are supported by the supporting device in a state where their axes S coincide with each other, and welding is performed while being rotated by the supporting device. At this time, the relative rotation is regulated by the engagement between the engaging portion 62 provided near the center 61 and the rotation stopper 78.

For both parts 71 and 72 in contact,
A pressure is applied by the center 61 to make a pressure contact state, and this pressure contact state is continued for a predetermined time. The two components 71 and 72 which relatively rotate in the pressure contact state generate heat at a high temperature due to sliding between the joint end faces thereof. After the relative rotation in the pressure-contact state is continued for a predetermined time, the relative rotation of the two parts 71 and 72 is stopped, and a stronger pressure is applied to both parts to press the two parts 71 and 72 together. As a result, the joint end surfaces of the two components 71 and 72 are welded and fixed. After that, similarly to the first embodiment, machining including outer shape cutting, formation of a coating layer, polishing of the coating layer, and cutting of the projection 79 are performed.

The present embodiment also provides the same effects as (1) of the first embodiment. The embodiment is not limited to the above-described configuration, and may be configured as follows, for example.

As shown in FIG. 5, the material 56 does not necessarily have a shape in which a plurality of piston materials 55 are connected,
The pistons may be formed one by one from the piston material 55 for one piston.

The material 56 is not limited to the shape in which the necks are connected to each other, and may be a shape in which the heads are connected to each other or the head and the neck are connected. Further, a shape in which three or more piston materials 55 are continuous may be used.

The present invention is not limited to the single-head type, and may be applied to the manufacture of a double-headed piston as shown in FIG. As shown in FIG. 7A, the detent 58 does not necessarily have to be provided symmetrically with respect to the supported portion, but may be provided on only one side.

○ As shown in FIG.
7 may be configured by directly providing a hole (recess) at the end of the piston. In this case, the amount of material used for the piston material is reduced.

The detent and the supported portion may be formed at positions separated from each other. The shape of the supported portion may be a shape other than the rotating body, and the shape of the support portion may be fitted to the shape to provide a function as a detent. For example, by making the cross section of the hole of the supported portion a shape other than a circle, for example, a polygon, relative rotation with the support portion is prevented.

The relative rotation may be prevented by forming the rotation stopper as a concave portion (hole) and the engaging portion as a convex portion. ○ The detent does not necessarily need to be removed, and may be left on the piston if it does not interfere with the role of the piston, such as the one provided on the neck side.

The detent may be provided only at one end of the piston. ○ A detent may be provided at a place other than the end face of the material. In the piston composed of two parts, the welding method is not limited to friction welding, and another welding method such as welding beam welding may be used.

Next, technical ideas other than those described in the claims which can be grasped from the embodiment will be described below together with their effects. (1) The method of manufacturing a piston according to claim 1, further comprising a step of cutting off the rotation stopper after the processing step. By adding such a step, the weight of the piston can be reduced.

[0053]

According to the present invention having the above-described structure, the piston can be manufactured efficiently by preventing the relative rotation of the piston with the supporting portion of the supporting device during machining.

[Brief description of the drawings]

FIG. 1 (a) is a schematic view of a partially broken material, and FIG. 1 (b) is a side view of the material.

FIG. 2 is a perspective view of a piston.

FIGS. 3A and 3B are schematic diagrams illustrating a coating process of a coating material on a predetermined surface of a material.

FIG. 4 is a sectional view of a two-part piston.

FIG. 5 is a partially cutaway schematic view of a material showing another example.

FIG. 6 is a partially cutaway schematic view of a material showing another example.

FIG. 7A is a side view of a material showing another example,
(B) is a partial sectional view of a material showing another example.

FIG. 8 is a longitudinal sectional view of a single-head piston type variable displacement compressor.

FIG. 9 is a schematic diagram illustrating the operation of the piston rotation restricting structure.

FIG. 10 is a schematic view of a material according to the related art.

[Explanation of symbols]

50 ... piston, 56 ... material, 57 ... supported part, 58 ...
Detent, 59 ... convex part, 60 ... center hole, 61 ... center, 62 ... engaging part, 71 ... head side part constituting piston, 72 ... neck part part constituting piston, 77 ... supported part, 78: detent, 79: convex part.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Shigeo Fukushima 2-1-1 Toyota-cho, Kariya-shi, Aichi F-term in Toyota Industries Corporation (reference) 3H003 AA03 AB07 AC03 AD03 CB00 CE04 3H076 AA06 BB50 CC31 CC34 CC99 4E067 AA05 BG00 DD00 DD02 EA08 EB00 EC06

Claims (4)

[Claims] A step of forming a piston material having a detent and a supported portion at at least one end; and a supporting portion for supporting the supported portion and an engaging portion for engaging the detent. And supporting the raw material in a state in which the raw material is not rotated relative to a supporting portion by a supporting device provided with the raw material, and processing the raw material while rotating the raw material. 2. The method for manufacturing a piston of a compressor according to claim 1, wherein the processing is a cutting processing including a cutting processing of an outer peripheral surface of the piston. 3. The method for manufacturing a piston of a compressor according to claim 1, wherein the processing is a coating process of applying a coating material to an outer peripheral surface of the piston by a transfer unit. 4. A method for manufacturing a piston of a compressor comprising two parts joined while rotating relative to each other, wherein a supported part is provided at an end opposite to a joined part of at least one of the two parts. A supporting device provided with a detent and a supporting part for supporting the supported part and an engaging part for engaging with the detent, supporting the two parts in a state where they are not relatively rotated and rotating the two parts. A method for manufacturing a piston of a compressor, which performs a processing including a welding process for joining parts.