US20140147317A1

US20140147317A1 - Compressor with swash plate

Info

Publication number: US20140147317A1
Application number: US14/118,944
Authority: US
Inventors: Oliver Tschismar
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2011-05-23
Filing date: 2012-03-29
Publication date: 2014-05-29
Also published as: WO2012159800A1; CN103547802A; DE102011076251A1

Abstract

A compressor has a swash plate which comprises a friction plate and an inner plate. The friction plate is arranged radially on the outside around the inner plate. The friction plate and the inner plate are connected to one another in a material-to-material manner.

Description

BACKGROUND OF THE INVENTION

The invention relates to a compressor with a swash plate as well as to a method for producing a swash plate of a compressor.
Compressors with swash plate are known from the prior art. Such a compressor is, for example, described in the German patent specification DE 101 60 555 A1. Compressors with swash plate are used, for example, in air conditioning systems as air conditioning compressors for compressing a refrigerant.
During the operation of a compressor provided with a swash plate, friction occurs between the swash plate and piston shoes of pistons of the compressor. In order to optimize the frictional torque that occurs, it is known to form the swash plate from suitable materials or to coat said swash plate with suitable materials. As a result, material and production costs of the swash plate however increase.

SUMMARY OF THE INVENTION

The aim of the present invention is to provide an improved compressor comprising a swash plate. This aim is met by a compressor according to the invention. It is further the aim of the present invention to specify an improved method for producing a swash plate of a compressor. This aim is met by a method according to the invention.
An inventive compressor has a swash plate which comprises a friction plate and an inner plate. The friction plate is thereby arranged radially on the outside around the inner plate. In addition, the friction plate and the inner plate are connected to one another in a material-to-material manner. A compressor comprising such a swash plate can be produced more cost effectively than a conventional compressor comprising a conventional swash plate.
The inner plate preferably consists of steel. Steel advantageously constitutes a cost effective and robust material.
In one embodiment of the compressor, the friction plate consists of steel. The friction plate can also then be simply and cost effectively produced.
In a further embodiment of the compressor, the friction plate consists of a copper alloy. A frictional torque occurring between the friction plate and piston shoes of the compressor can be optimized by using a copper alloy for the friction plate.
In a particularly preferable manner, the friction plate is coated. The surface of the friction plate can then be formed such that a frictional torque occurring between the friction plate and piston shoes of the compressor can advantageously be optimized during the operation of the compressor.
In one embodiment of the compressor, the friction plate is coated with PTFE (polytetrafluroethylene). PTFE advantageously constitutes a suitable and commercially available coating agent.
In a further embodiment of the compressor, the inner plate has a frustoconical outer circumference and the friction plate has a frustoconical inner circumference. As a result, the contact surface is advantageously enlarged between the inner plate and the friction plate which facilitates a robust connection between inner plate and friction plate.
In another embodiment of the compressor, the inner plate has a stepped outer circumference. The inner plate and the friction plate then advantageously abut against one another in an axial region, whereby a larger contact surface is likewise formed between inner plate and friction plate, which facilitates a robust connection between inner plate and friction plate.
In one embodiment of the compressor, said compressor is an air conditioning compressor. The compressor can than be inserted into an air conditioning unit for the purpose of compressing a refrigerant.
A method according to the invention for producing a swash plate of a compressor comprises the following steps: providing an inner plate, providing a friction plate, arranging the friction plate on an outer circumference of the inner plate and connecting the friction plate to the inner plate in a material-to-material manner. Said method advantageously facilitates a simple and cost effective production of the swash plate of the compressor.
In one embodiment of the method, the friction plate and the inner plate are connected to one another by means of friction welding. In this method, a permanent and robust material-to-material connection advantageously results between friction plate and inner plate.
In another embodiment of the method, the friction plate and the inner plate are connected to one another by means of magnetic pulse welding. A material-to-material connection of friction plate and inner plate also advantageously results from this operation.
In a further embodiment of the method, the friction plate and the inner plate are connected to one another by means of spot welding. This advantageously constitutes a variant of the method which is particularly easy to carry out.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be explained in detail with the aid of the attached drawings. In the drawings:

FIG. 1 shows a schematic depiction of a cross-section through a compressor according to a first embodiment; and

FIG. 2 shows a schematic depiction of a cross-section through a compressor according to a second embodiment.

DETAILED DESCRIPTION

In a slightly schematized depiction, FIG. 1 shows a cross-section through a compressor 10 according to a first embodiment. The compressor 10 can, for example, be an air conditioning compressor of an air conditioning unit and serve to compress a refrigerant of the air conditioning unit. The compressor 10 can, however, also be any other compressor.
The compressor 10 comprises a cylinder block 11 and a front housing 12 attached to the cylinder block 11. The front housing 12 and the cylinder block 11 together form a crankcase 13 of the air conditioning compressor 10.
The cylinder block 11 comprises one or a plurality of cylinders, in which a piston 14 is movably disposed in each case. In FIG. 1, only one cylinder comprising a piston 14 disposed therein is visible. Each of the cylinders comprises intake and exhaust valves that are not specified. The intake valves are provided to deliver a medium to be compressed to the respective cylinder. The medium delivered to the cylinder is compressed by means of the piston 14 disposed in the cylinder and is subsequently let out of said cylinder via the exhaust valve.
A drive shaft 15 is disposed in the crankcase 13 formed by the cylinder block 11 and the front housing 12. The drive shaft 15 can be rotated with respect to the crankcase 13 about the longitudinal axis thereof. A support plate 16 is fixed to the drive shaft 15 in order together with the drive shaft 15 to carry out a rotational movement about the longitudinal axis of said drive shaft 15.
A swash plate 20 is furthermore disposed in the crankcase 13. The swash plate 20 is substantially formed in the shape of a round disc and has a central through-hole, through which the drive shaft 15 extends. The central through-hole of the swash plate 20 is dimensioned such that said swash plate 20 does not have to be exactly perpendicularly oriented to the longitudinal direction of the drive shaft 15 but can be inclined relative to said drive shaft 15.
The swash plate 20 comprises an inner plate 40 and a friction plate 30. The friction plate 30 can also be referred to as an annular plate. The inner plate 40 can also be referred to as a sleeve or a bushing. The inner plate 40 forms a radially inner portion of the swash plate 20 and comprises the central through-hole, through which the drive shaft 15 extends. The friction plate 30 forms a radially outer region of the swash plate 20 and is arranged radially on the outside around the inner plate 40 The friction plate 30 and the inner plate 40 of the swash plate 20 are connected to one another in a material-to-material manner. The inner plate 40 further has a counterweight section 42 which is disposed radially opposite to the hinge 17 and is supported on the support plate 16.
The inner plate 40 of the swash plate 20 is connected via a hinge 17 to the support plate 16. A rotation of the drive shaft 15 about the longitudinal axis of said drive shaft 15 can be transmitted to the swash plate 20 via the support plate 16 and the hinge 17, whereby the swash plate 20 is displaced in a rotation about the longitudinal axis of the drive shaft 15.
A compression spring 18 is wound around the drive shaft 15 between the support plate 16 and the swash plate 20 and pretensions said swash plate 20 in the direction of the cylinder block 11. The incline of the swash plate 20 can be reduced by displacing said swash plate 20 in the direction of the cylinder block 11.
The friction plate 30 of the swash plate 20 is coupled via a pair of piston shoes 21 to the piston 14. The friction plate is also accordingly coupled via further piston shoes 21 to all other pistons 14 of the compressor 10. The friction plate 30 is slidably arranged between the piston shoes 21. One piston shoe of each pair of piston shoes 21 lies on the front side and the other piston shoe 21 of each pair of piston shoes on the rear side of the friction plate 30 of the swash plate 20. A rotational movement of the swash plate 20 about the longitudinal axis of the drive shaft 15 is translated via the friction plate 30 and the piston shoes 21 into a periodic longitudinal movement of the piston 14 in the cylinder of the cylinder block 11. The stroke of the piston 14 can be changed by changing the incline of the swash plate 20 with respect to the drive shaft 15.
In the air conditioning compressor 10 of the first embodiment depicted in FIG. 1, the inner plate 40 of the swash plate 20 has a frustoconical outer circumference 41. The friction plate 30 of the swash plate 20 has a frustoconical inner circumference 31. The outer circumference 41 of the inner plate 40 is therefore not oriented perpendicularly to the plate plane of the swash plate 20 but is inclined relative to a perpendicular orientation. Accordingly the inner circumference 31 of the friction plate 30 is also not oriented perpendicularly to the plate plane of the swash plate 20 but is inclined relative to a perpendicular orientation. The frustoconical outer circumference 41 of the inner plate 40 and the frustoconical inner circumference 31 of the friction plate 30 are dimensioned in such a way that said friction plate 30 can be arranged around the inner plate 40 such that the frustoconical inner circumference 31 of the friction plate 30 planarly rests against the frustoconical outer circumference 41 of the inner plate 40.
The frustoconical outer circumference 41 of the inner plate 40 and the frustoconical inner circumference 31 of the friction plate 30 are connected to one another in a material-to-material manner. The outer circumference 41 of the inner plate 40 and the inner circumference 31 of the friction plate 30 are preferably connected to one another by means of a welding process. In a particularly preferable manner, the inner plate 40 and the friction plate 30 are connected to one another by means of friction welding. It is, however, also possible to connect the inner plate 40 and the friction plate 30 to one another by means of magnetic pulse welding or by means of spot welding.
The inner plate 40 can, for example, consist of steel. The friction plate 30 of the swash plate 20 can, for example, consist of a copper alloy. The friction between the friction plate 30 and the piston shoes 21 can advantageously be optimized by using a copper alloy for the friction plate 30 of the swash plate 20. The friction plate 30 of the swash plate 20 can, however, alternatively consist of the same material as the inner plate 40, for example of steel. In this case, the friction plate 30 of the swash plate 20 is preferably coated with a material which provides for optimized friction between the friction plate 30 and the piston shoes 21. The friction plate 30 of the swash plate 20 can, for example, be coated with a copper alloy. The friction plate 30 can also alternatively be coated with PTFE (polytetrafluroethylene; also known under the trade name Teflon).
In a slightly schematized depiction, FIG. 2 shows a cross-section through a compressor 110 according to a second embodiment. The second compressor 110 can likewise be an air conditioning compressor for compressing a refrigerant in an air conditioning unit. The compressor 110 of the second embodiment can, however, be any other compressor. The design of the compressor 110 pursuant to the second embodiment, which is depicted in FIG. 2, corresponds to a great extent to the compressor 10 of the first embodiment which is depicted in FIG. 1. The same reference numerals were therefore used in FIGS. 1 and 2 for identical components or components which function in the same way. These components as well as the general operations of the compressor 110 are not once again explained.
In contrast to the compressor 10 of the FIG. 1, the compressor 110 of FIG. 2 has an altered swash plate 120. The swash plate 120 comprises an inner plate 140 and a friction plate 130. The friction plate 130 is substantially designed annularly and is arranged around the inner plate 140 in a radially circumferential manner.
The inner plate 140 of the swash plate 120 has a stepped outer circumference 142. In an axial direction, the inner plate 140 therefore comprises a first section having a first diameter and a second section having a second diameter which is greater than the first diameter. A perpendicular step running in a radial direction extends between the two sections. The friction plate 130 of the swash plate 120 has a cylindrical inner circumference 131, the diameter of which approximately corresponds to the diameter of the first section of the outer circumference 141 of the inner plate 140. The friction plate 130 is arranged around the inner plate 140 such that the cylindrical inner circumference 131 of the friction plate 130 planarly rests against the first section of the stepped outer circumference 141 of the inner plate 140, i.e. against the section of the stepped outer circumference 141 which has the smallest diameter. In addition, the friction plate 130 of the swash plate 120 is supported on the step in the stepped outer circumference 141 of the inner plate 140. This results in an axial contact region between the cylindrical inner circumference 131 of the friction plate 130 and the first section of the stepped outer circumference 141 of the inner plate 140 as well as a radial contact region between a front side of the friction plate 130 and the step of the stepped outer circumference 141 of the inner plate 140.
The friction plate 130 and the inner plate 140 are in turn connected to one another in a material-to-material connection. The friction plate 130 and the inner plate 140 can be connected to one another by means of friction welding, magnetic pulse welding or spot welding. The use of another welding process is also possible.
The friction plate 130 and the inner plate 140 of the swash plate 120 can consist of the same material or of different materials. The inner plate can, for example, consist of steel. The friction plate 130 can, for example, consist of a copper alloy or of steel coated with a copper alloy. The friction plate 130 can, however, also consist of another material or be coated with another material.

Claims

1. A compressor (10, 110) with a swash plate (20, 120), characterized in that the swash plate (20, 120) comprises a friction plate (30, 130) and an inner plate (40, 140), wherein the friction plate (30, 130) is arranged radially on an outside around the inner plate (40, 140), the friction plate (30, 130) and the inner plate (40, 140) being connected to one another in a material-to-material manner.

2. The compressor (10, 110) according to claim 1, wherein the inner plate (40, 140) consists of steel.

3. The compressor (10, 110) according to claim 1, wherein the friction plate (30, 130) consists of steel.

4. The compressor (10, 110) according to claim 1, wherein the friction plate (30, 130) consists of a copper alloy.

5. The compressor (10, 110) according to claim 3, wherein the friction plate (30, 130) is coated.

6. The compressor (10, 110) according to claim 5, wherein the friction plate (30, 130) is coated with PTFE.

7. The compressor (10) according to claim 1, wherein the inner plate (40) has a frustoconical outer circumference (41) and the friction plate (30) has a frustoconical inner circumference (31).

8. The compressor (110) according to claim 1, wherein the inner plate (140) has a stepped outer circumference (141).

9. The compressor (10, 110) according to claim 1, wherein the compressor (10, 110) is an air conditioning compressor.

10. A method for producing a swash plate (20, 120) of a compressor (10, 110) comprising the following steps:

providing an inner plate (40, 140);

providing a friction plate (30, 130);

arranging the friction plate (30, 130) on an outer circumference (41, 141) of the inner plate (40, 140); and

connecting the friction plate (30, 130) to the inner plate (40, 140) in a material-to-material manner.

11. The method according to claim 10, wherein the friction plate (30, 130) and the inner plate (40, 140) are connected to one another by means of friction welding.

12. The method according to claim 10, wherein the friction plate (30, 130) and the inner plate (40, 140) are connected to one another by means of magnetic pulse welding.

13. The method according to claim 10, wherein the friction plate (30, 130) and the inner plate (40, 140) are connected to one another by means of spot welding.

14. The compressor (10, 110) according to claim 2, wherein the friction plate (30, 130) consists of steel.

15. The compressor (10, 110) according to claim 4, wherein the friction plate (30, 130) is coated.

16. The compressor (10, 110) according to claim 15, wherein the friction plate (30, 130) is coated with PTFE.