Expansible chamber devices – Relatively movable working members – Interconnected with common rotatable shaft
Reexamination Certificate
1999-01-04
2001-02-13
Look, Edward K. (Department: 3745)
Expansible chamber devices
Relatively movable working members
Interconnected with common rotatable shaft
C091S505000
Reexamination Certificate
active
06186048
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to variable displacement compressors that are used, for example, in vehicle air conditioners.
Examples of the variable displacement compressors are disclosed in Japanese unexamined patent publication No. 8-311634 and No. 9-60587. A housing of the respective variable displacement compressor defines cylinder bores, each of which receives a piston. The housing rotatably supports a drive shaft, and a rotor is fixed to the drive shaft. Furthermore, a pivotal swash plate, which is connected to the piston, engages and is guided by the drive shaft. The swash plate is often made of aluminum or aluminum alloy material to reduce the weight of the compressor. A hinge mechanism connects the rotor to the swash plate. The swash plate is rotated integrally with the drive shaft through the rotor and the hinge mechanism. The hinge mechanism permits pivotal motion and sliding motion of the swash plate.
The hinge mechanism includes a first hinge part, which extends from the swash plate, and a second hinge part, which extends from the rotor. The hinge mechanism further includes a pair of guide pins. A base end of each guide pin is press fitted into a corresponding mounting hole of the first hinge part. A distal end of each guide pin is slidably received in a corresponding guide hole of the second hinge part. When the swash plate is moved in an axial direction of the drive shaft, the distal end of each guide pin slides in the corresponding guide hole to guide the motion of the swash plate.
Rotation of the drive shaft is converted to reciprocation of each piston through the rotor, the hinge mechanism and the swash plate. During the back stroke of the piston, from top dead center to bottom dead center, the refrigerant gas is drawn into the cylinder bore. Then, during the forward stroke of the piston, from bottom dead center to top dead center, the refrigerant gas is compressed in the cylinder bore and, then, is discharged from the cylinder bore. The displacement of the variable displacement compressor can be adjusted by changing the inclination of the swash plate to change the stroke of the piston.
In the prior art, the first hinge part is integrally formed with the swash plate. That is, the first hinge part is also made of aluminum or aluminum alloy material. Therefore, in comparison to first hinge parts that are integrally formed with an iron-based swash plate, an aluminum-based first hinge part is less rigid. As a result, it is difficult to form an aluminum-based first hinge part that has satisfactory strength. Furthermore, it is difficult to press fit the base end of the guide pin into the mounting hole of an aluminum-based first hinge part in a manner that assures satisfactory strength.
Therefore, when an iron-based swash plate is replaced with an aluminum-based swash plate for reducing the weight of the compressor, the strength and durability of the hinge mechanism are reduced.
SUMMARY OF THE INVENTION
The present invention addresses the above disadvantages. It is an objective of the present invention to provide a variable displacement compressor that has a light weight drive plate and a strong hinge mechanism.
Basically, the variable displacement compressor of this invention has a housing, wherein a cylinder bore is formed in the housing, a piston located in the cylinder bore, a drive shaft rotatably supported by the housing, a rotor mounted on the drive shaft to rotate integrally with the drive shaft, a drive plate, and a hinge mechanism. The drive plate is made of aluminum or aluminum alloy material and is connected to the piston to convert rotation of the drive shaft to reciprocation of the piston. The drive plate inclines and slides axially along the drive shaft, which varies the piston stroke to change the displacement of the compressor. The hinge mechanism is located between the rotor and the drive plate for rotating the drive plate integrally with the rotor and for guiding the motion of the drive plate. The hinge mechanism includes a first hinge part, which is made of iron-based metal material and is connected to the drive plate, and a second hinge part, which extends from the rotor. The first and second hinge parts are coupled to one another to permit both pivoting and sliding motion between the first and second hinge parts.
REFERENCES:
patent: 5057274 (1991-10-01), Futamura et al.
patent: 5785503 (1998-07-01), Ota et al.
patent: 5984643 (1999-11-01), Ota et al.
patent: 8-311634 (1996-11-01), None
patent: 9-60587 (1997-03-01), None
Hirota Suguru
Kato Keiichi
Kayukawa Hiroaki
Kimura Kazuya
Kabushiki Kaisha Toyoda Jidoshokki Seisakusho
Lazo Thomas E.
Look Edward K.
Morgan & Finnegan L.L.P.
LandOfFree
Variable displacement compressor does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Variable displacement compressor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Variable displacement compressor will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2563992