JP2002349428A - Method for manufacturing variable displacement compressor and tool used in this method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent generation of welding strain in the case of connecting functional parts by welding after a swash plate or a rotor is formed to be divided into the parts classified by the function. SOLUTION: After a swash plate is formed to be divided into a swash plate main unit 28 mounted inclinably movably and slidably relating to a drive shaft and a link member 32 constituting partly a hinge mechanism, the link member 32 is connected to the swash plate main unit 28 by fillet welding. This welding is operated in a condition that a reverse strain amount ΔL1 corresponding to a shrinkage strain amount if given in a reverse direction to a strain direction by shrinkage to be generated to the swash plate main unit 28 after welding.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a variable displacement compressor used in, for example, a vehicle air conditioner.

[0002]

2. Description of the Related Art A variable displacement compressor is disclosed in, for example,
No. 1-264371. FIG. 8 shows a single-headed piston type variable displacement compressor described in the above publication. A swash plate 102 is slidably mounted on a drive shaft 101 which is rotated from a vehicle engine via a clutch in a state where the swash plate 102 is inclined. The rotation of the drive shaft 101 is performed by a rotor 103 fixed to the drive shaft 101. From the swash plate 102 via the hinge mechanism 104. A piston 106 is connected to the swash plate 102 via a shoe 105, and the piston 106 reciprocates in a cylinder bore 107 to suck, compress, and discharge refrigerant gas in the cylinder bore 107. Also, the swash plate 102
Is configured to be able to change the tilt angle while sliding on the drive shaft 101. By changing the tilt angle, the stroke amount of the piston 106 is changed and the discharge capacity is adjusted. The rotor 103 includes a base portion 108 as a fixed function portion with respect to the drive shaft 101 and a hinge mechanism 10.
4 includes a link portion 109 as a hinge function portion for transmitting torque by forming a part of the weight portion 4, and a weight portion 110 for adjusting the weight balance so that the center of gravity coincides with the rotation axis. The hinge mechanism 104 includes a link portion 109 of the rotor 103 and a hinge pin 113 provided on the swash plate 102 and having a spherical head slidably engaged with the link portion 109. The hinge pin 113 of the swash plate 102 is implanted in an arm 112 provided on the swash plate main body 111.

In the above-described variable displacement compressor, for example, the swash plate 102 has an arm portion 112 formed integrally with a swash plate main body 111 by casting. In such a molding method by casting, since it is impossible to form a complicated shape or a thin-walled shape, for example, it is unavoidable that an excess thickness is unavoidable in the vicinity of the protruding and formed arm portion 112, which results in an increase in size and Large weight was caused. This is also true for the rotor 103. That is, the rotor 103 includes the base portion 108, the link portion 109, and the weight portion 110 as a single member, and is formed by casting. Therefore, swash plate 1
The same problem as 02 occurs. Therefore, in order to reduce the weight and cost of the swash plate or the rotor in the variable displacement compressor, the swash plate or the rotor is replaced with, for example, a cold-rolled steel plate or carbon steel for machine structure (S35C, S35C).
There has been proposed a concept in which a functional material is divided from a plate material (plate) such as 45C) by a press, and then the functional components are joined to each other. For example, the swash plate 102 is formed by being divided into a swash plate main body 111 and an arm portion 112 and then joined, and the rotor 103 is formed by being divided into a base portion 108 and a link portion 109 and then joined. For the joining, the simplest method is, for example, welding.

[0004]

However, when a joining structure by welding is employed, so-called welding distortion occurs in which the base material (the swash plate main body 111 and the base portion 108) warps toward the joining surface due to shrinkage during cooling. . This welding distortion has an adverse effect on the stroke amount of the piston and brings about a problem that the top clearance varies. Therefore, there is a problem in that post-processing of strain removal is required after welding.

The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide a variable displacement compressor in which a swash plate or a rotor is divided into functional parts and formed. An object of the present invention is to prevent the occurrence of welding distortion when joining the functional components by welding.

[0006]

In order to achieve the above object, a method of manufacturing a variable displacement compressor according to the present invention has a configuration as described in each of the claims. In the method for manufacturing a variable displacement compressor according to the first aspect, a step of forming a swash plate body that is attached to be tiltable with respect to a drive shaft and a link member that constitutes a part of a hinge mechanism. Joining the link member to the swash plate body by welding to obtain a swash plate, wherein the welding reduces the amount of shrinkage strain in a direction opposite to a strain direction due to shrinkage generated after welding to the swash plate body. This is performed in a state where a corresponding amount of reverse distortion is given. As a result, the shrinkage strain due to cooling after welding and the reverse strain of the amount given corresponding to the amount of shrinkage strain are offset, and as a result, the occurrence of shrinkage strain of the swash plate body is suppressed. be able to. That is, according to the first aspect of the present invention, it is possible to provide a swash plate free of shrinkage distortion in a variable displacement compressor.

According to a second aspect of the present invention, there is provided a method for manufacturing a variable displacement compressor, comprising: a base member fixed to a drive shaft;
Forming a link member constituting a part of the hinge mechanism, and a step of obtaining a rotor by joining the link member to a base member by welding, wherein the welding is performed by welding to the base member. The configuration is such that the reverse distortion is applied in the direction opposite to the direction of the distortion caused by the contraction that occurs later, in a direction corresponding to the contraction distortion amount. As a result, the shrinkage strain due to cooling after welding and the reverse strain of the amount given corresponding to the amount of shrinkage strain are offset, and as a result, the occurrence of shrinkage strain of the base member is suppressed. Can be. That is, according to the second aspect of the present invention, it is possible to provide a rotor having no shrinkage distortion in the variable displacement compressor. In the welding process according to claims 1 and 2, the reverse strain applied to the swash plate main body or the base member is in the form of elastic reverse strain, that is, within the range of elastic deformation of the swash plate main body or the base member. And plastic deformation, that is, the plastic deformation of the swash plate main body or the base member by an amount corresponding to the contraction strain in advance.

In the method for manufacturing a variable displacement compressor according to the third aspect, in the welding step, the reverse strain applied to the swash plate main body or the base member is elastic reverse strain, and the elastic reverse strain is determined by welding. It is added before starting work,
It is configured to be released after welding is completed. When such a configuration is adopted, the residual stress of the swash plate main body or the base member after welding can be reduced or avoided.

The jig used in the method for manufacturing a variable displacement compressor according to the present invention is a jig for imparting an elastic reverse strain to a swash plate main body or a base member in a welding process, wherein the swash plate main body or the base is provided. A first pressing member that applies an external force to the center of the member in the axial direction; and a second pressing unit that applies an external force to the outer peripheral side of the swash plate body or the base member in a direction opposite to the direction in which the first pressing member applies the external force. And a pressure member. According to such a configuration, reverse distortion can be effectively applied to the swash plate main body or the base member.

[0010]

FIG. 1 is a block diagram showing an embodiment of the present invention.
This will be described with reference to FIG. As shown in FIG. 1, the front housing 1 is joined to a front end surface of a cylinder block 2. The rear housing 3 is joined to a rear end surface of the cylinder block 2 via a valve plate 4. The front housing 1, the cylinder block 2, and the rear housing 3 constitute a housing of the compressor. The crank chamber 5 is formed so as to be surrounded by the front housing 1 and the cylinder block 2. The drive shaft 6 is
It is supported rotatably between the front housing 1 and the cylinder block 2 and penetrates through the crank chamber 5. The drive shaft 6 is connected to a vehicle engine (not shown) as an external drive source via a clutch mechanism such as an electromagnetic clutch. Therefore, the drive shaft 6 is rotationally driven by the connection of the clutch mechanism when the vehicle engine is started.

A rotor 7 is fixedly secured to the drive shaft 6 so as to be integrally rotatable in the crank chamber 5. The swash plate 8
The drive shaft 6 is housed in the crank chamber 5 in a state where the drive shaft 6 is inserted through an insertion hole 8 a penetrating through the center. Rotor 7
And a swash plate 8, a hinge mechanism 20 is interposed,
Both are connected. The hinge mechanism 20 includes a link member 23 provided on the rotor 7, a link member 32 provided on the swash plate 8, and a hinge pin 33 connecting the two link members 23, 32.

In the cylinder block 2, a plurality of cylinder bores 2a are formed at predetermined intervals around the axis L of the drive shaft 6, and the tip of the single-headed piston 11 is
Is housed in The rear end of the piston 11 is moored to the outer periphery of the swash plate 8 via a pair of shoes 12. Therefore, the rotational motion of the drive shaft 6 is transmitted through the rotor 7, the hinge mechanism 20, the swash plate 8 and the shoe 12 to the piston 11.
The piston 11 reciprocates in the cylinder bore 2a as the swash plate 8 rotates.

The suction chamber 3a and the discharge chamber 3b are separately arranged in the rear housing 3. Suction port 4
a, the suction valve 4b, the discharge port 4c, and the discharge valve 4d are formed on the valve plate 4, respectively. The refrigerant gas in the suction chamber 3a is sucked into the cylinder bore 2a via the suction port 4a and the suction valve 4b by moving from the top dead center side of the piston 11 to the bottom dead center side. Cylinder bore 2
The refrigerant gas sucked into a is compressed to a predetermined pressure by moving from the bottom dead center side of the piston 11 to the top dead center side, and is discharged to the discharge chamber 3b through the discharge port 4c and the discharge valve 4d. Is done.

The bleed passage 15 includes a crank chamber 5 and a suction chamber 3a.
And connect. The air supply passage 16 connects the discharge chamber 3 b and the crank chamber 5. The capacity control valve 17 which is an electromagnetic valve is interposed on the air supply passage 16. The opening degree of the air supply passage 16 is adjusted by the capacity control valve 17, the pressure of the crank chamber 5 is changed, and the crank chamber 5 acting before and after the piston 11 is changed.
And the pressure of the cylinder bore 2a is adjusted.
As a result, the inclination angle of the swash plate 8 is changed, the stroke amount of the piston 11 is changed, and the discharge capacity is adjusted.

Next, the rotor 7 will be described with reference to FIGS. The rotor 7 is formed separately for each functional component. That is, the base member 22 is fixed to the drive shaft 6 as a fixed function part, and the link member 23 is formed as a hinge function part constituting a part of the hinge mechanism. The base member 22 has a disk shape having a through hole 22a at the center, and is fixedly fixed to the drive shaft 6 inserted through the through hole 22a so as to be integrally rotatable. The through-hole 22a is formed in a boss 22b that extends the base member 22 rearward along the drive shaft 6.

A thrust bearing 25 is interposed between the front surface of the base member 22 and the front housing 1. The thrust bearing 25 surrounds the drive shaft 6, and a roller 25 a as a rolling member directly contacts the front surface of the base member 22. The compression reaction force (load in the thrust direction) generated by the reciprocating operation of the piston 11 is received by the front housing 1 via the piston 11, the shoe 12, the swash plate 8, the hinge mechanism 20, and the thrust bearing 25.

A link member 23 constituting one of the hinge mechanisms 20 is formed separately from the base member 22, and a top dead center of the swash plate 8 for defining a top clearance of the piston 11 is provided on an upper rear surface of the base member 22. It is provided at a site corresponding to the corresponding position D. The link member 23 includes a horizontally long mounting plate 23a having a through hole 23c at the center, and a link portion 23b that is raised substantially at a right angle by bending the upper end of both ends of the mounting plate 23a to the rear side (in plan view). ) Is formed in a substantially U-shape. Left and right link parts 23
b has a long hole 26 that extends obliquely downward. The link member 23 formed as described above is attached to the upper portion of the rear surface of the base member 22 such that the left and right link portions 23b are arranged on both left and right sides across the axis L of the drive shaft 6, as shown in FIG. . That is, welding is performed in a state where the through-hole 23c of the mounting plate 23a is fitted to the boss portion 22b of the base member 22.

At the lower portion of the rear surface of the base member 22, a weight 2 is provided.
4 are integrally formed. As mentioned above, rotor 7
By providing the link member 23 on the upper side of the rear surface, the center of gravity of the rotor 7 is eccentric from the axis L of the drive shaft 6 which is the center of rotation. In order to eliminate this bias, the weight portion 24 is provided at the lower end of the rear surface of the rotor 7 opposite to the link member 23 when viewed from the axis L of the drive shaft 6 which is the center of rotation. The center of gravity of 7 is adjusted to coincide with the rotation axis (the axis L of the drive shaft 6).

Next, the swash plate 8 will be described with reference to FIGS. The swash plate 8 is formed for each functional component similarly to the rotor 7. That is, the swash plate 8 includes a swash plate main body 28 as a piston pressurizing function component slidably attached to the drive shaft 6 in an inclined state, and a link member 32 as a hinge function component constituting the other of the hinge mechanism 20. It is formed separately. The swash plate main body 28 is formed in a substantially disk shape having a boss 28a projecting to the front side at the center,
The drive shaft 6 is inserted into a through hole 8a formed in the boss 28a so as to be tiltable.

The link member 32 has a mounting plate 32a having a through hole 32c at the center, and a link portion 32 which is raised substantially at a right angle by bending both ends of the mounting plate 32a to the front side.
and b are formed in a substantially U-shape in plan view (top view). At the upper end of the left and right link portions 32b, a mounting hole 32d for the hinge pin 33 is provided. Link member 32
Is attached to the front side of the swash plate main body 28. That is,
The boss 28a of the swash plate main body 28 has a through hole 3 formed in the mounting plate 32a.
It is joined by welding with the 2c fitted. Link member 3
2 are arranged such that the left and right link portions 32b overlap the inside of the left and right link portions 23b of the link member 23 on the rotor 7 side, and are connected by hinge pins 33. The hinge pin 33 penetrates through the mounting hole 32d of the link member 32 on the swash plate 8 side and is slidably engaged with the long hole 26 of the link member 23 on the rotor 7 side. Therefore, the swash plate 8
Due to the slide guide relationship with the elongated hole 26 of the link member 23 and the slide support action of the drive shaft 6 through the insertion hole 8a, the slide member can be slid with respect to the drive shaft 6 while tilting in the direction of the axis L thereof. The maximum inclination angle of the swash plate 8 at the time of the maximum capacity is determined by the abutment surface 32 formed on the lower front surface of the link portion 32b of the link member 32 on the swash plate 8 side.
e is the mounting plate 23 of the link member 23 on the rotor 7 side.
It is regulated by abutting the rear surface of a.

The swash plate 8 configured as described above is manufactured by being divided into a swash plate main body 28 and a link member 32 and then joined by welding. Hereinafter, a method of manufacturing the swash plate 8 will be described with reference to FIGS. As shown in FIG. 3, the swash plate main body 28 and the link member 32 are punched, punched, bent, and drawn from a plate material such as a cold-rolled steel plate or carbon steel for machine structure (S35C, S45C). By performing such processes as described above, each is individually formed into a predetermined shape. Next, the link member 32 is joined to the swash plate main body 28 by fillet welding in a T-shaped joint mode.
In this case, in the case of welding in a normal mode, as shown in FIG. 7, after welding, the swash plate main body 28 is warped to the joining surface side of the link member 32 due to shrinkage during cooling and solidification. ΔL (indicated by the dotted line) occurs.

Therefore, in the present embodiment, in order to eliminate the above-described shrinkage distortion, the direction of the shrinkage caused by the shrinkage generated after welding to the swash plate main body 28 using the jig 50 before welding is performed. In the opposite direction, an amount of elastic reverse strain corresponding to the amount of contraction strain is applied. As shown in FIGS. 4 and 5, the jig 50 includes a welding table 51 on which the swash plate main body 28 is placed and a pressing arm 52 for applying an external force to the swash plate main body 28 from above.
And a liner 53 inserted between the upper surface of the welding table 51 and the swash plate main body 28. A predetermined external force is applied by a pressing arm 52 from the upper part on the outer peripheral side of the swash plate main body 28 placed on the liner 53 with the boss 28a facing upward, thereby bending the swash plate main body 28 as shown in the drawing to cause contraction distortion. A reverse distortion of the amount ΔL1 corresponding to the amount is given. The reverse strain in this case is a strain given within the elastic deformation range, that is, an elastic reverse strain. The liner 53 corresponds to a first pressing member according to the present invention, and the pressing arm 52 corresponds to a second pressing member according to the present invention.

When the swash plate main body 28 is elastically strained as described above, the link member 32 is set so that the through hole 32c is fitted into the boss portion 28a of the swash plate main body 28. Are joined by fillet welding in the form of a T-shaped joint. In the present embodiment, four locations around the mounting plate 32a are welded, and the weld locations are indicated by reference numeral 40. In addition, MAG welding,
Although MIG welding, TIG welding, and CO ₂ welding can be used, a welding method of a type that does not generate spatter is particularly preferable. Then, after welding, the application of the elastic reverse strain by the jig 50 is released. By performing such an operation, the shrinkage strain due to cooling after welding and the reverse strain of the amount given corresponding to the amount of shrinkage strain are offset, and as a result, the swash plate main body 28 Generation of shrinkage distortion can be suppressed. Therefore, according to the present embodiment, in the variable displacement compressor, the swash plate 8 having no shrinkage distortion is used.
Can be provided.

The amount of shrinkage distortion generated after welding depends on the swash plate body 2
8, the thickness, the material, the size of the welding portion 40, and the like. Therefore, the amount of elastic reverse strain given to the swash plate main body 28 in advance is:
It is determined after confirming by a test so that the amount of shrinkage strain after welding becomes zero. Also, as in the present embodiment, the mounting plate 3
When four places around 2a are intermittently (spot-like) welded, it is preferable to press each with the pressing arm 52 on a straight line extending from the center of the swash plate main body 28 in the direction of the welding place (FIG. 5). reference). In this case, the tip (pressing surface) of the pressing arm 52 is preferably formed in an opening shape (bowl shape) as shown in FIG. 4, in which case the contact area with the swash plate body 28 is reduced, and This is effective in preventing the surface of the swash plate main body 28 from being damaged by the pressure.

It should be noted that the present invention is not limited to the above-described embodiment, and can be implemented with appropriate modifications without departing from the scope of the invention. In the above-described embodiment, as the reverse strain applied to the swash plate main body 28 prior to welding, a description has been given of the case of the reverse strain within the elastic deformation range of the swash plate main body 28, that is, the elastic reverse strain. Reverse strain due to plastic deformation may be applied. That is, in anticipation of the amount of contraction strain after welding, the swash plate main body 28 is plastically deformed (curved) in advance in the direction opposite to the contraction distortion by an amount corresponding to the amount of contraction distortion, and no constraint is applied by the jig 50 ( It is also possible to carry out the embodiment in which welding is performed in a free state.

Although the above-described embodiment is directed to the swash plate 8, it may be applied to a method for manufacturing the rotor 7. That is, as a first step, the prepared working material such as a cold-rolled steel plate or carbon steel for machine structure (S35C, S45C) is subjected to press working so that the drive shaft 6 is pressed.
And a link member 23 that constitutes a part of the hinge mechanism 20 are individually formed. Second
As a step, the link member 23 is joined to the base member 22 by fillet welding in the form of a T-joint. This welding is performed in a state where an amount of reverse strain corresponding to the amount of shrinkage strain is applied to the base member 22 in the direction opposite to the direction of strain caused by shrinkage occurring after welding. As a result, as in the case of the swash plate 8, a rotor without shrinkage distortion can be provided.

Further, the hinge mechanism 20 is configured such that the hinge pin 33 is engaged with the long hole 26 of the left and right link portions 23b of the link member 23 on the rotor 7 side.
The link portion 23b is changed to a long hole 26 to form a vertical cylinder as shown in FIG. 8, and a hinge pin having a spherical head provided on a link member 32 on the swash plate 8 side is provided in the cylindrical hole. You may change to the structure engaged in a vertical sliding direction. Also, the link portion 2 of the link member 23 on the rotor 7 side
3b is formed in a substantially C-shape in plan view, and the C-shape is changed to a configuration in which hinge pins having a spherical head provided on the link member 32 on the swash plate 8 side are respectively engaged in the vertical sliding direction. Is also good.

In the above-described embodiment, the base member 2
Although the weight portion 24 is formed integrally with the base member 2, the present invention can be applied to a case where the weight portion 24 is formed separately from the base member 22 and is joined by welding. Further, in the embodiment, the case where the number of the welding points 40 is four is shown. However, the number of welding points can be arbitrarily determined, and the periphery may be continuously welded.

[0029]

As described in detail above, according to the present invention,
In a variable capacity compressor, after forming a swash plate or a rotor by dividing it into functional parts, when joining the functional parts by welding, it is possible to join without causing welding distortion, and to remove distortion after welding. Troublesome post-processing is not required.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a variable displacement compressor.

FIG. 2 is a diagram schematically showing a hinge mechanism from above.

FIG. 3 is a diagram illustrating a press-formed swash plate main body and a link member.

FIG. 4 is a view showing a welding process of the link member to the swash plate main body.

FIG. 5 is a view of FIG. 4 as viewed from above.

FIG. 6 is a view showing a swash plate as a finished product after welding.

FIG. 7 is a view showing shrinkage strain after welding.

FIG. 8 is a longitudinal sectional view showing a conventional technique.

[Explanation of symbols]

 Reference Signs List 6 drive shaft 7 rotor 8 swash plate 11 piston 20 hinge mechanism 22 base member 23 rotor side link member 26 long hole 28 swash plate main body 32 swash plate side link member 33 hinge pin 50 jig 51 welding table 52 pressure arm 53 liner

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tomoji Tarutani 2-1-1 Toyota-cho, Kariya-shi, Aichi Prefecture Inside Toyota Industries Corporation (72) Inventor Hirohiko Tanaka 2-1-1 Toyota-cho, Kariya-shi, Aichi F-term in Toyota Industries Corporation (Reference) 3H076 AA06 BB50 CC20 CC99

Claims (4)

[Claims] A drive shaft, a swash plate attached to the drive shaft in an inclined state, a piston coupled to the swash plate so as to reciprocate in a cylinder bore by rotation of the swash plate, A rotor attached to a drive shaft; and a hinge mechanism provided between the rotor and the swash plate, the hinge mechanism connecting the swash plate to the rotor so as to be tiltable and capable of transmitting torque. A method for manufacturing a variable displacement compressor in which the stroke amount of the piston changes according to a change in the inclination angle of the swash plate body, the swash plate body being tiltably and slidably attached to the drive shaft; Forming a link member constituting a part of a hinge mechanism; and joining the link member to the swash plate body by welding to obtain the swash plate, wherein the welding is performed by the swash plate. Board A method of manufacturing a variable displacement compressor, wherein a main body is subjected to an amount of reverse strain corresponding to the amount of shrinkage strain in a direction opposite to a strain direction due to shrinkage generated after welding. 2. A drive shaft, a swash plate attached to the drive shaft in an inclined state, a piston connected to reciprocate in a cylinder bore by rotation of the swash plate with respect to the swash plate, A rotor attached to a drive shaft; and a hinge mechanism provided between the rotor and the swash plate, the hinge mechanism connecting the swash plate to the rotor so as to be tiltable and capable of transmitting torque. A method of manufacturing a variable displacement compressor in which a stroke amount of the piston changes in accordance with a change in the inclination angle of a base member fixed to the drive shaft, and a link member forming a part of the hinge mechanism And a step of welding the link member to the base member by welding to obtain the rotor, wherein the welding is performed after the base member is shrunk after welding. A method for manufacturing a variable displacement compressor, characterized in that the method is performed in a state in which an amount of reverse strain corresponding to the amount of shrinkage strain is applied in a direction opposite to the direction of strain caused by compression. 3. The method of manufacturing a variable displacement compressor according to claim 1, wherein the reverse strain applied to the swash plate body or the base member in the welding step is elastic strain. The method for manufacturing a variable displacement compressor, wherein the elastic strain is added before the welding operation is started and is released after the welding is completed. 4. A jig used in the method for manufacturing a variable displacement compressor according to claim 1.
A first pressing member that applies an external force to the central portion of the swash plate main body or the base member in an axial direction; and an external force applying direction by the first pressing member to an outer peripheral side of the swash plate main body or the base member. And a second pressing member for applying an external force in the opposite direction.