JPH0355674B2 - - Google Patents

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a swash plate type compressor that compresses a flow of refrigerant, for example, and particularly relates to a swash plate type compressor that compresses a flow of refrigerant, and in particular, a method for changing the inclination angle of the swash plate by making the inclination angle of the swash plate variable. The present invention relates to a variable capacity compressor whose compression capacity can be changed by changing the compression capacity.

[Prior art] Conventional variable capacity compressors are
As described in Japanese Patent Publication No. 59-26793, etc., the outer periphery is designed so that the size and distribution of the mass of the rotating member of the rotating swash plate assembly is balanced with the rotational couple generated by the reciprocating motion of the piston, etc. A resistance weight is attached, a balance ring is attached to the tip of the hub portion of the rotating swash plate, and a thrust bearing is used to restrict the axial movement of the oscillating plate toward the cylinder block.

[Problems to be Solved by the Invention] Incidentally, such a variable capacity compressor has a complicated structure, and specifications using thrust bearings increase cost, and it is difficult to miniaturize each compressor. It had the disadvantage of being trapped.

[Means for Solving the Problems] In order to solve the above problems, the present invention provides a drive shaft that extends into a crank chamber adjacent to a cylinder block having a plurality of cylinders, and a variable inclination angle with respect to the drive shaft. and a swash plate connected to the drive shaft so as to rotate together with the drive shaft; a rocking plate set on an inclined surface of the swash plate to be rotatable relative to the swash plate; A rotation prevention mechanism that prevents rotation of the swash plate when the swash plate rotates and causes the swash plate to perform a rocking motion; and a piston that reciprocates within the cylinder, and the stroke of the piston changes according to a change in the inclination angle of the swash plate, and the compression capacity changes. A balance weight for suppressing an increase in the static unbalance and dynamic unbalance of the inertial forces of the swash plate, the oscillating plate, and the piston system due to changes in the inclination angle of the oscillating plate is provided on the surface of the oscillating plate facing the cylinder block. This is characterized in that a sliding contact portion is provided on a portion of the balance weight to restrict the axial movement of the swing plate toward the cylinder block.

[Example] Hereinafter, an example of the present invention will be described with reference to FIGS. 1 and 2.

A cylinder block 3 having a plurality of cylinders (only one shown) 2 is provided at one end of the compressor housing 1, and the other end is closed by a front end plate 4. A crank chamber 5 is formed within the housing between the cylinder block 3 and the front end plate 4. A drive shaft 6 is provided from the outside of the front end plate 4, passing through the front end plate 4, and extending into the crank chamber 5. This drive shaft 6 is rotated by the front end plate 4 and the cylinder block 3. movably supported.

In the crank chamber 5, a rotor 7 is attached to the drive shaft 6 so as to be rotatable together with the drive shaft. A swash plate 8 is hinged to a portion of the rotor 7 in the radial direction by a pin 9. Therefore, the swash plate 8 is rotatable together with the rotor 7,
Moreover, because of the hinge connection, the angle of inclination with respect to the drive shaft 6 is variable.

A rocking plate 29 is mounted on the inclined surface of the swash plate 8 on the side opposite to the rotor 7 via a radial bearing 10 and a thrust bearing 11 so as to be rotatable relative to the swash plate. Reference numeral 12 denotes a guide that engages with a portion of the swing plate 29 to prevent rotation of the swing plate while guiding the swing of the swing plate. Swing plate 29
One end of a plurality of piston rods (only one is shown) 13 is ball-coupled to the end in the system direction at equal angular intervals, and the other end of the piston rod 13 is
It is coupled to a piston 14 within the cylinder 2.

A cylinder head 16 is mounted on the outer surface of the cylinder block 3 via a valve plate 15. The cylinder head 16 is formed with a suction chamber 17 and a discharge chamber 18, and is provided with a suction port 19 and a discharge port 20 communicating with each other. A suction hole 21 and a discharge hole 22 are formed in the valve plate 15 to communicate the cylinder 2 with the suction chamber 17 and the discharge chamber 18, respectively.
The suction hole 21 and the discharge hole 22 are each provided with a suction valve and a discharge valve (both not shown).

A communication hole 23 is formed through the cylinder block 3 and the valve plate 15 to connect the crank chamber 5 and the suction chamber 17. A pressure sensitive chamber 24 is formed in the middle of this communication hole 23, and this pressure sensitive chamber 24
A bellows valve 25 is provided inside to open and close the communication hole 23. That is, when the pressure within the crank chamber 5 exceeds a predetermined pressure, the bellows valve 25 opens the communication hole 23, thereby reducing the pressure within the crank chamber. On the other hand, when the pressure within the crankshaft reaches a predetermined level or lower, the bellows valve 25 closes the communication hole 23.

In the above configuration, when the drive shaft 6 is rotated by a driving force from an external drive source (not shown) via an electromagnetic clutch 26, the swash plate 8 is rotated via the rotor 7. At this time, the swing plate 29
Since rotation is prevented by the guide 12, the swash plate 8 swings as the swash plate 8 rotates. As a result, the piston 14 is transferred to the cylinder 2 via the piston rod 13.
reciprocating within. Due to the reciprocating motion of the piston, gas is sucked into the cylinder 2 through the suction port 19, suction chamber 17, and suction hole 21, compressed, and discharged into the discharge chamber 18 through the discharge hole 22, and then externally through the discharge port 20. delivered to the fluid circuit.

During this time, the gas 2 sucked into the cylinder 2 passes through the play between the cylinder inner wall and the piston and blows into the crank chamber 5 as blow-by gas. If the crank chamber pressure is below the setting, the bellows valve 25
closes the communication hole 23 and the pressure inside the crank chamber 5 increases.

When the pressure in the crank chamber 5 increases, the back pressure of the piston 14 increases, so the movement of the piston 14 toward the bottom dead center is restricted. As a result, the swash plate 8
rotates around the pin 9, and the angle of inclination with respect to the drive shaft 6 becomes smaller. As a result, the stroke of the piston becomes smaller and the compression capacity is reduced.

Further, when the pressure inside the crank chamber 5 increases and becomes equal to or higher than a predetermined value, the bellows valve 25 opens the communication hole 23. As a result, the crank chamber 5 communicates with the suction chamber 17, and the pressure within the crank chamber 5 decreases. This reduces the back pressure on the piston 14 and reduces the restriction on the movement of the piston toward the bottom dead center.
The angle of the swash plate 8 with respect to the drive shaft 6 becomes large. Thus, the stroke of the piston is increased and the compression capacity is increased.

In addition, a balancing ring 32 is used at the tip of the hub portion of the rotating swash plate so that the size and distribution of the mass of the rotating member of the rotating swash plate assembly is balanced with the rotation couple generated by the reciprocating motion of the piston, etc. .

The above configuration and operation are basically the same as those of the conventional variable capacity compressor disclosed in the aforementioned Japanese Patent Publication No. 58-4195, Japanese Patent Publication No. 59-26793, etc.

In order to solve the above-mentioned drawbacks of such conventional variable capacity compressors, in this embodiment, a portion is provided on the surface of the balance weight 32 on the front end plate 4 side to make sliding contact with the rocking plate 29. The balance weight swash plate is connected to the balance weight swash plate to restrict movement of the cylinder block of the oscillation plate in the lateral axial direction.

[Effects of the Invention] According to the present invention, it is possible to provide a variable capacity compressor that is small, lightweight, low cost, and has well-balanced rotation.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a variable capacity swash plate compressor according to a positional embodiment of the present invention, and is a diagram also referred to in the description of the conventional example. FIG. 2 is a diagram showing essential parts according to the present invention. 2...Cylinder, 3...Cylinder block, 5
...Crank chamber, 6...Drive shaft, 8...Italic, 9
...Winging plate, 12...Guide (for preventing rotation), 1
4...Piston, 31...Balance weight.

Claims (1)

[Scope of Claims] 1. A drive shaft extending into a crank chamber adjacent to a cylinder block having a plurality of cylinders, and connected to the drive shaft such that the inclination angle with respect to the drive shaft is variable and the drive shaft rotates together with the drive shaft. swash plate,
A rocking plate is provided on an inclined surface of the swash plate so as to be rotatable relative to the swash plate; The swash plate has a rotation prevention mechanism that causes the swash plate to perform a swinging motion, and a piston that is connected to the swash plate and reciprocates within the cylinder due to the swing motion of the swash plate. In a variable capacity compressor in which the stroke of the piston changes as the angle changes, and the compression capacity changes, A balance weight for suppressing an increase in static unbalance and dynamic unbalance of inertial force is provided on a surface of the rocking plate facing the cylinder block and connected to the swash plate, and a part of the balance weight 1. A variable capacity swash plate type compressor, characterized in that a sliding contact portion is provided for regulating the axial movement of the oscillating plate toward the cylinder block.