JP2000283025A - Swash plate type variable displacement compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the rigidity of a swash plate coupling part. SOLUTION: In a swash plate 18 installed by screwing a screw hole 19 to the screw part 16 provided on the outer periphery of the boss 15 of a journal 14, a nut acceptance groove 28 is provided on one side hole edge of the screw hole 19 and one end of a nut 29 threadedly engaged with the screw part 16 enters in the nut acceptance groove 28 and pressingly tightens the swash plate 18 and the effective number of threads of the swash plate 18 for the screw part 16 is obtained as the sum of the number of threads of the screw hole 19 and the number of threads of the nut 19. By increasing a threadedly engaged margin of the swash plate 18 for the screw part 16, the rigidity of the swash plate coupling part is increased.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a swash plate type variable displacement compressor which is interposed in a refrigeration cycle of a vehicle air conditioner or the like and is used for compressing refrigerant gas.

[0002]

2. Description of the Related Art A swash plate type variable displacement compressor is disclosed in, for example, Japanese Patent Application Laid-Open No. 7-103138. The swash plate to be converted is separately molded in consideration of their workability, and a screw portion is formed on the outer periphery of the boss portion of the journal,
A screw hole is formed in the center of the swash plate, and the screw hole is screwed into a screw portion on the outer periphery of the boss portion, whereby the swash plate and the journal are integrally connected and fixed.

[0003]

When the piston is actuated by the swash plate, a large load is applied to the swash plate at the screwed portion with the threaded portion on the outer periphery of the boss of the journal. It is necessary to increase the effective number of screws to increase the margin of the screw hole with respect to the screw portion on the outer periphery of the boss portion, and to increase the resistance of the swash plate connecting portion.

Therefore, the portion of the swash plate in which the screw hole is formed is formed thick to secure an allowance for the screw hole on the screw portion on the outer periphery of the boss portion by the thick portion. In order to form a thick portion at the center of the swash plate, a flat material having a thickness greater than the thick portion is used and cut into a required thickness to form a thick portion at the center. Since the cutting process is performed, not only the number of steps for the cutting process is increased, but also the product yield is poor and the cost is disadvantageous.

A portion of the swash plate where the pair of shoes are in sliding contact with each other with the outer peripheral portion interposed therebetween is polished and surface-finished in order to enhance smoothness. However, a thick portion exists at the center of the swash plate. As a result, there is a step on the side surface of the swash plate, so that the polishing workability is poor and the cost is disadvantageously increased.

In view of the above, the present invention is to increase the screw allowance of the swash plate to the journal boss without increasing the thickness of the swash plate as a whole or forming a thick portion at the center of the swash plate. To provide a swash plate type variable displacement compressor which can increase the rigidity of the swash plate coupling portion.

[0007]

According to the first aspect of the present invention, a thread is formed on the outer periphery of a boss portion of a journal that rotates integrally with a drive shaft, while the rotation of the drive shaft is converted into a linear motion of a piston. A screw hole is formed in the center of the swash plate to be screwed, and the screw hole is screwed into the screw portion of the boss portion to screw the swash plate into the boss portion of the journal. An annular nut receiving groove is formed at the hole edge opposite to the swash plate screwing direction of the hole, and a nut whose one end enters the nut receiving groove is screwed into a screw portion on the outer periphery of the boss portion. The swash plate is clamped by means of.

According to a second aspect of the present invention, the nut according to the first aspect is characterized in that the nut is provided with a flange portion abutting on a side surface of the swash plate.

According to the invention of claim 3, claims 1 and 2
The swash plate described in (1) is characterized by being formed flat with a constant thickness from the outer periphery to the inner periphery.

[0010] In the invention of claim 4, claims 1 to 3 are provided.
A plurality of tool engagement holes penetrating through both side surfaces are provided in the vicinity of the screw holes of the swash plate described in (1).

[0011]

According to the first aspect of the present invention, the swash plate is clamped by the nut having one end inserted into the nut receiving groove at the center of one side of the swash plate, and the threaded portion on the outer periphery of the boss portion of the journal. Is obtained as the sum of the number of screws in the screw holes of the swash plate and the number of screws in the nut with respect to the swash plate. Therefore, the rigidity of the swash plate connecting portion can be increased without increasing the thickness of the swash plate, and the quality and reliability can be improved.

Further, the swash plate can be fixed by a double nut system by screwing the swash plate itself and a nut to a threaded portion on the outer periphery of the boss portion so that the swash plate can be securely mounted without loosening. It can be performed.

According to the second aspect of the present invention, the first aspect is provided.
In addition to the effects of the invention, the flange of the nut abuts against the side surface of the swash plate, and the holding area of the joint portion of the swash plate can be increased, so that the swash plate's falling rigidity can be increased.

According to the third aspect of the present invention, in addition to the effects of the first and second aspects of the present invention, the swash plate has a flat structure with no change in plate thickness, so that the formability of the swash plate is improved. At the same time, surface finishing by polishing is also facilitated, so that cost can be advantageously obtained.

According to the invention described in claim 4, according to claim 1 of the present invention,
In addition to the effects of the third to third aspects, in addition to the screw holes of the swash plate, a plurality of tool engagement holes for attaching and detaching the swash plate are provided through both side surfaces of the swash plate. The hole functions as an oil reservoir, and the oil contained in the mist in the refrigerant and adhering to the side surface of the swash plate can be caught and stored in the tool engagement hole. The oil stored in this tool engagement hole can be supplied to the shoe sliding contact surface of the outer peripheral portion on both sides of the swash plate by force, and the oil replenishing property to the sliding contact with the shoe is improved and lubrication Performance can be improved.

[0016]

Embodiments of the present invention will be described below in detail with reference to the drawings.

1 and 2, reference numeral 1 denotes a compressor housing, a cylinder block 2 having a plurality of cylinder bores 3.
A front housing 4 that is arranged on the front side of the cylinder block 2 to form a crank chamber 5 with the cylinder block 2, and that is arranged on the rear side of the cylinder block 2 with a valve plate 9 interposed therebetween. And a rear housing 6 forming a refrigerant suction chamber and a refrigerant discharge chamber 8.

A drive shaft 10 is provided in the crank chamber 5.
, A journal 14 connected to a sleeve 12 slidably fitted on a drive shaft 10 by a pin 13 so as to be swingable, and a thread formed on the outer periphery of a boss 15 of the journal 14. 16 and a swash plate 18 in which a screw hole 19 is screwed and fixed.

The journal 14 has its hinge arm 20 connected to the hinge arm 21 of the drive plate 11 via an arc-shaped long hole 22 and a pin 23 of the hinge arm 21, and the swing is regulated by the long hole 22. It is supposed to be.

A piston 24 disposed in each cylinder bore 3
Is connected to the swash plate 18 via a pair of shoes 25 sandwiching the swash plate 18.

The swash plate 18 is provided, for example, in the rear housing 6.
The tilt angle is controlled by the pressure in the crank chamber 5 which is adjusted by controlling the flow rate of the refrigerant flowing into the refrigerant suction chamber by the pressure control valve mechanism 26 provided in the swash plate 18. The displacement of the refrigerant is changed by changing the stroke.

The swash plate 18 is formed flat with a constant thickness from the outer periphery to the inner periphery, and an annular spacer 27 is provided between one side surface and the flange portion 17 of the journal 14. The screwing position is regulated by the spacer 27.

An annular nut receiving groove 28 is formed at the edge of the screw hole 19 of the swash plate 18 opposite to the swash plate screwing direction.

Numeral 29 denotes a nut screwed into the threaded portion 16 on the outer periphery of the boss of the journal 14. One end of the nut is inserted into the nut receiving groove 28 of the swash plate 18 and is brought into contact with the groove bottom. The swash plate 18 is pressed.

In this embodiment, a flange 29 is integrally formed on the periphery of the nut 29, and the flange 30 is brought into contact with the side surface of the swash plate 18, so that the end of the nut 29 and the flange 30 are joined together. The swash plate 18 is clamped.

Further, a position near the screw hole 19 of the swash plate 18,
Specifically, a plurality of tool engagement holes 31 are provided on both sides of the nut 29 at positions separated from the flange portion 30 and the spacer 27 on the opposite side.

The number of the tool engaging holes 31 is a multiple of the number of engaging claws of a swash plate tightening tool (not shown). For example, if there are three engaging claws, the number of tool engaging holes 31 is six, and The tool engagement hole 31
Is formed in an arc-shaped long hole so that the engaging claw is easily captured and engaged.

In FIG. 1, 32 is a reed valve for opening and closing a discharge port 33 of the valve plate 9, 34 is a reed valve for opening and closing a suction port (not shown) of the valve plate 9, and 35 is a valve that supports the reed valve 32 and has an opening degree. 3 shows a retainer that regulates the pressure.

According to the structure of the above embodiment, the central screw hole 19 is screwed into the screw portion 16 provided on the outer periphery of the boss portion 15 of the journal 14, and the flange portion of the journal 14 is Swash plate 18 fixed by pressing against 17
One end of a nut 29 screwed into the screw portion 16 enters a nut receiving groove 28 provided at the center of the side opposite to the screwing direction of the swash plate 18. The effective screw number of the swash plate 18 with respect to the screw portion 16 is obtained as the sum of the screw number of the screw hole 19 of the swash plate 18 and the screw number of the nut 29. Generation can be increased and therefore
The rigidity of the swash plate connecting portion can be increased without increasing the thickness of the swash plate 18, thereby improving the quality and reliability.

As described above, the swash plate 18 is fixed by a double nut method by screwing the swash plate 18 itself and the nut 29 to the screw portion 16 on the outer periphery of the boss portion 15 as described above. As a result, the swash plate can be securely mounted without loosening.

In particular, in the present embodiment, the nut 29 is provided integrally with the flange 30, and the flange 30 abuts against the side surface of the swash plate 18 to increase the holding area of the joint portion of the swash plate 18. The falling rigidity of the swash plate 18 can be further increased.

Further, since the swash plate 18 has a constant thickness from the outer periphery to the inner periphery and has a flat structure having no thick portion at the center unlike the conventional swash plate,
In addition, the moldability of No. 8 is improved, and surface finishing by polishing is also facilitated, so that it can be advantageously obtained in terms of cost.

Further, a plurality of tool engagement holes 31 for attaching and detaching the swash plate 18 are provided in the vicinity of the screw holes 19 of the swash plate 18 so as to penetrate both sides of the swash plate 18. Since the tool engagement hole 31 functions as an oil reservoir, the oil contained in the refrigerant in the form of mist and adhering to the side surface of the swash plate can be captured and stored in the tool engagement hole. When the machine is started, the oil stored in the tool engagement holes can be supplied to the shoe sliding contact surface side of the outer peripheral portions on both sides of the swash plate by centrifugal force, and the oil replenishing property to the sliding contact portion with the shoe 25 is improved. The lubrication can be improved by improving the lubrication.

[Brief description of the drawings]

FIG. 1 is a sectional view showing one embodiment of the present invention.

FIG. 2 is an enlarged explanatory view showing a main part of the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Drive shaft 14 Journal 15 Boss part 16 Screw part 18 Swash plate 19 Screw hole 24 Piston 28 Nut receiving groove 29 Nut 30 Flange 31 Tool engagement hole

Claims (4)

[Claims] 1. A thread (16) is formed on the outer periphery of a boss (15) of a journal (14) rotating integrally with a drive shaft (10), while a drive shaft (10) is formed.
A screw hole (19) is formed at the center of the swash plate (18) for converting the rotation of the piston into linear motion of the piston (24), and the screw hole (19) is screwed into the screw portion (16) of the boss (15). And screw the swash plate (18) into the boss (1) of the journal (14).
5) In the structure adapted to be screwed into the swash plate (18), an annular nut receiving groove (28) is formed at the hole edge of the screw hole (19) of the swash plate (18) on the side opposite to the swash plate screwing direction. A nut (29), one end of which enters the nut receiving groove (28), is screwed into the screw portion (16) on the outer periphery of the portion (15), and the swash plate (18) is pressed with the nut (29). A swash plate type variable displacement compressor characterized in that: 2. The swash plate type variable displacement compressor according to claim 1, wherein the nut (29) includes a flange portion (30) abutting on a side surface of the swash plate (18). 3. The swash plate type variable displacement compressor according to claim 1, wherein the swash plate (18) is formed flat with a constant thickness from the outer periphery to the inner periphery. 4. The swash plate (18) has a plurality of tool engagement holes (31) penetrating on both sides near the screw holes (19). A swash plate type variable displacement compressor according to any one of the above.