JP2861478B2 - Piston displacement mechanism in oscillating swash plate compressor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a single-headed piston which rotates the swash plate through a displacement mediating member interposed between both sides of a swash plate supported on a rotating shaft and a neck of a single-headed piston. The present invention relates to a piston displacement mechanism in a variable displacement type swash plate type compressor that controls the inclination angle of a swash plate by a difference between a pressure in a crank chamber and a suction pressure through a single-headed piston, while converting the pressure into a reciprocating linear motion. .

[0002]

2. Description of the Related Art In a compressor of this type disclosed in Japanese Patent Application Laid-Open No. 60-175783, a spherical portion of a hemispherical shoe is fitted into and supported by a spherical concave portion of a neck of a single-headed piston. The end face is in contact with the swash plate surface. With such a shoe support structure, the single-headed piston can reciprocate in the rotation axis direction with the rotation of the swash plate. Oscillating swash plate compression system in which a swash plate is rotatably supported on a rotating plate that is tiltable to a rotating shaft and rotatably supported integrally with the rotating shaft, and a swash plate and a single-headed piston are connected by a piston rod. Although a swash plate anti-rotation mechanism is required in the compressor, the swinging swash plate type compressor disclosed in Japanese Patent Application Laid-Open No. Sho 60-177583 does not require a rotating plate and a swash plate anti-rotation mechanism, and the mechanism is significantly simplified.

[0003]

However, the rotation of the swash plate causes the single-headed piston to receive a load from the swash plate to the side via the shoe, thereby causing a one-sided contact between the cylinder bore and the single-headed piston. For this reason, there is a possibility that abrasion may occur at a contact portion between the single-headed piston and the cylinder bore, or seizure may occur.

[0004] It is an object of the present invention to provide a piston displacement mechanism which can reduce a lateral load received by a single-headed piston from a swash plate.

[0005]

According to the present invention, there is provided:
A pair of displacement mediating members are interposed between one surface of the swash plate and the single-headed piston, and an annular support member that supports the first displacement mediating member so as to be relatively displaceable only in the circumferential direction is provided on one surface of the swash plate. Around the single-ended piston, a displacement guide member is provided at the neck of the single-headed piston to guide the second displacement mediating member only in the radial direction of the swash plate so that both displacement mediating members can slide in the radial direction of the swash plate. Mated.

[0006]

With the rotation of the swash plate, the second displacement mediating member moves to the first position.
The load is applied laterally from the swash plate via the displacement mediating member. As a result, the second displacement mediating member is displaced in the radial direction of the swash plate along the displacement guide strip on the single-headed piston side, and the lateral load received by the single-headed piston from the swash plate is reduced in the radial direction of the second displacement mediating member. Is absorbed and relaxed by the displacement to

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, one embodiment of the present invention will be described with reference to the first to first embodiments.
This will be described with reference to FIG. A front housing 2 and a rear housing 3 are joined and fixed to the front and rear of a cylinder block 1 which is a part of a housing of the entire compressor. A rotary shaft 4 is rotatably supported on the cylinder block 1 and the front housing 2. I have. Front housing 2
A rotary support 5 is fixed to the rotary shaft 4 inside, and an elongate hole 5a is provided at the tip side thereof.

[0008] A spherical bush 6 is slidably supported on the rotating shaft 4, and a swash plate 7 is supported on the bush 6 so as to be rotatable in the direction of the rotating shaft 4. A connecting piece 7a is attached to the swash plate 7, and a pin 7 is attached to the tip of the connecting piece 7a.
b is attached. The pin 7b is engaged with the long hole 5a, and the long hole 5a guides the tilt of the swash plate 7 through the pin 7b. Thereby, the swash plate 7 can swing about the bush 6 in the direction of the rotation shaft 4 and can rotate integrally with the rotation shaft 4.
The tilting of the swash plate 7 is guided by the slide guide action of the elongated hole 5a and the pin 7b, the slide action of the bush 6, and the support action of the bush 6.

A single-headed piston 8 is accommodated in a cylinder bore 1a provided through the cylinder block 1 so as to connect the crank chamber 2a, the suction chamber 3a and the discharge chamber 3b in the rear housing 3. A swash plate passage groove 9a is provided in the neck portion 9 of the single-headed piston 8, and displacement guide grooves 9b are provided along the radial direction of the swash plate 7 on both end surfaces of the swash plate passage groove 9a. Swash plate 7 passing through swash plate passage groove 9a
The outer periphery side of an annular support rail 7c is formed, the center of radius is set on the axis L ₁ of the rotating shaft 4.

[0010] As shown in FIG.
Are arranged at equal intervals around the rotation shaft 4, and a pair of displacement mediating members 10, 11 are interposed between the neck 9 of each single-headed piston 8 and the annular support rail 7c. As shown in FIG. 3, the first displacement mediating member 10 has a semi-cylindrical shape, and its rectangular end face is slidably fitted and supported on the annular support rail 7c. The second displacement mediating member 11 fits into the displacement guide groove 9b having an arc-shaped cross section, and
Of the displacement mediating member 10 is fitted and supported.

[0011] peripheral surface axis L ₂ of the first displacement-mediated member 10 of the semi-cylindrical shape is set on the center between the front and rear pair of annular support rails 7c, arc center axis of the displacement guide groove 9b of the circular arc cross sectional shape L ₃ is set on the axis L _2. Therefore, the two displacement mediating members 10 and 11 are always fitted and supported without any gap in the swash plate passage groove 9a regardless of the swash plate rotation angle, and the rotation axis of the first displacement mediating member 10 accompanying the rotation of the swash plate 7 is supported. distance variation from L ₁ is allowed by the sliding displacement of the second displacement-mediated member 11 along the displacement guide groove 9b. Therefore, the rotational movement of the swash plate 7 is caused by the two displacement mediating members 10,
11 is converted into a back and forth reciprocation of the single-headed piston 8,
The single-headed piston 8 moves back and forth in the cylinder bore 1a. Thereby, the refrigerant gas sucked into the cylinder bore 1a from the suction chamber 3a is discharged to the discharge chamber 3b while being compressed.
The stroke of the single-headed piston 8 changes according to the pressure difference between the pressure in the crank chamber 2a and the suction pressure in the cylinder bore 1a through the single-headed piston 8, and the inclination angle of the swash plate 7, which affects the compression capacity, changes. The pressure in the crank chamber 2a is controlled by an electromagnetic control valve mechanism 19 in the cylinder block 1.

The rotation axis L of the first displacement mediating member 10₁Or
The one-head piston accompanying the rotation of the swash plate 7
8 has the effect of reducing the lateral load on the neck 9
You. In the graph of FIG. 4, the single-headed piston 8 is received from the swash plate 7.
Chain line C representing the lateral load₁Is a conventional rocking swash plate
Represents the load curve to the side in the compressor of the type shown in FIG.
_TwoRepresents a lateral load curve of the present embodiment. Both curves C_1,C
_TwoAs is clear from FIG.
Is remarkable, and such a large suppression effect is caused by the second displacement.
Obtained by sliding the intermediate member 11 in the swash plate radial direction.
You.

Further, the sliding direction of the second displacement mediating member 11 with respect to the single-headed piston 8 is limited to the radial direction of the swash plate 7, and the sliding direction of the first displacement mediating member 10 is limited to the circumferential direction of the swash plate 7. Swash plate 7
Rolling does not occur with the rotation of. Therefore, there is no interference between the neck 9 of the single-headed piston 8 and the peripheral edge of the swash plate 7, and there is no need to separately provide a rolling prevention mechanism for the single-headed piston 8.

The present invention is, of course, not limited to the first embodiment, but may be, for example, the embodiments shown in FIGS. In the embodiment of FIG. 5, the annular support rail 12 has a semicircular cross section, and in the embodiment of FIG. 6, the annular support rail is replaced by an annular support groove 13. In the embodiment shown in FIG. 7, a displacement mediating member 14 in which a pair of displacement mediating members before and after the swash plate 7 in each of the above embodiments is integrated is used.

In the embodiment shown in FIG. 8, an annular support rail 7c is provided outside the area of the swash plate passage groove 9a of the single-headed piston 8, so that the foot 17a of the displacement mediating member 17 of the same type as the displacement mediating member 11 has an annular support rail. The fitting is supported by the rail 7c. This makes it possible to increase the sectional area of the annular support rail 7c,
The load bearing performance is improved. In the embodiment of FIG. 9, the first displacement mediating member 15 has a hemispherical shape, and the second displacement mediating member 1
6 and the first displacement mediating member 15 are spherically fitted. Therefore, the displacement guide groove 9c in the neck 9 of the single-headed piston 8
Any shape may be used as long as the second displacement mediating member 16 can be slid and guided only in the radial direction of the swash plate 7. A guide relationship is unnecessary.

The shape of the second displacement mediating member 16 may be as shown in FIG. In the embodiment shown in FIG. 11, the first displacement mediating member 15 shown in FIGS. 9 and 10 is combined with the type of the second displacement mediating member 11 shown in FIG.

[0017]

As described above in detail, according to the present invention, a pair of displacement mediating members are combined, and one of the displacement mediating members which is connected to the single-headed piston can be slid in the radial direction of the swash plate. The side load that the single-headed piston receives from the swash plate can be considerably partially absorbed by the sliding displacement of one displacement mediating member in the swash plate radial direction,
An excellent effect of preventing wear or seizure between the single-headed piston and the cylinder bore due to a lateral load can be achieved.

[Brief description of the drawings]

FIG. 1 is a side sectional view of the entire compressor.

FIG. 2 is a sectional view taken along line AA of FIG. 1;

FIG. 3 is an exploded perspective view of a main part.

FIG. 4 is a graph of a lateral load.

FIG. 5 is a sectional side view of a main part showing another example.

FIG. 6 is a sectional side view of a main part showing another example.

FIG. 7 is a sectional side view of a main part showing another example.

FIG. 8 is a sectional side view of a main part showing another example.

FIG. 9 is an exploded perspective view of a main part showing another example.

FIG. 10 is an exploded perspective view of a main part showing another example.

FIG. 11 is an exploded perspective view of a main part showing another example.

[Explanation of symbols]

7 swash plate, 7c support rail as annular support strip, 1
2,13 annular support groove, 8 single-ended pistons, 9b, 9c
Displacement guide grooves as displacement guide strips, 10, 14, 15
First displacement mediating member, 11, 16 A second displacement mediating member.

Claims (1)

(57) [Claims] A swash plate is tilted on a rotary shaft in a housing which defines a crank chamber, a suction chamber, a discharge chamber, and a cylinder bore connecting these chambers, and accommodates a single-headed piston in the cylinder bore so as to reciprocate linearly. Swash plate is tiltably linked to the rotating support on the rotating shaft,
The rotary motion of the swash plate is converted into a reciprocating linear motion of the single-head piston via a displacement mediating member interposed between both surfaces of the swash plate and the neck of the single-head piston, and the single-head piston of the pressure in the crank chamber and the suction pressure is converted. In a swinging swash plate type compressor in which the inclination angle of the swash plate is controlled by a difference through the swash plate, a pair of displacement mediating members are interposed between one side of the swash plate and the single-headed piston, and the first surface of the swash plate is An annular support member for supporting the displacement mediating member so as to be relatively displaceable only in the circumferential direction is provided around the rotation axis, and the second displacement mediating member can be displaced and guided only in the radial direction of the swash plate at the neck of the single-ended piston. A displacement guide strip is provided,
A piston displacement mechanism in an oscillating swash plate type compressor in which both displacement mediating members are slidably fitted in a radial direction of a swash plate.