JPH0338459Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) This invention relates to a swash plate type compressor, particularly a variable capacity compressor in which the compression capacity can be changed by changing the angle of inclination of the swash plate. be.

(Prior art) In a swash plate type compressor in which the rotation of the swash plate causes the swash plate to swing and reciprocate the piston, the angle of the swash plate relative to the drive shaft is changed in order to change the compression capacity. A variable compression capacity compressor in which the compression capacity is controlled by controlling the inclination angle of the swash plate is disclosed in, for example, Japanese Patent Application Laid-Open No.
It is known as disclosed in No. 77578.

The compressor described in JP-A No. 56-77578 is No. 5
As shown in the figure, a guide rod 100 parallel to the drive shaft is provided at a radially outer position of the rocking plate, and a hollow bearing is slidably fitted to this guide rod 100.
A pair of semi-cylindrical sliding metal members 102 that abut the outer surface of the bearing are slidably fitted into guide holes provided on the outer periphery of the rocking plate to prevent rotation.

In addition, in the compressor described in Japanese Patent Application No. 62-36444, as shown in FIG. 6, a columnar block 33 having a vertically divided groove formed in its tip portion is attached so as to be movable in the radial direction; Rotation is prevented by a guide plate 35 whose one side edge is fitted into the vertical groove of the columnar block 33 and whose both ends are rotatably supported by the front end plate and the cylinder block.

(Problem to be solved by the invention) In the rotation prevention mechanism (FIG. 5) for a compressor described in JP-A-56-77578, a hollow bearing 101 is sandwiched between a pair of sliding metal members 102, and The pair of sliding metal members 102 must be fitted into the guide holes of the rocking plate, and the guide rod 100 must be inserted into the width of the hollow bearing 101 to be assembled into the compressor housing while maintaining the assembled state. The metal member 102 is likely to fall out of the guide hole, and there is a risk that the combination of the rotation prevention mechanism may be disrupted, making installation into the compressor housing difficult and extremely complicated.

Furthermore, in the compressor described in Japanese Patent Application No. 62-36444, as shown in FIG. This is a contributing factor.

The purpose of this invention is to have a structure that allows the guide plate to be directly assembled into the housing, and a rotary structure that is easy to assemble, rather than assembling multiple parts that are easy to come apart and then incorporating them into the housing. The present invention provides a variable capacity compressor that is equipped with a blocking mechanism and that enables cost reduction by reducing the number of parts.

(Means for Solving the Problems) According to this invention, there is provided a housing having a cylinder block including a plurality of cylinders, a front end plate facing the cylinder block and supporting a drive shaft, and a cylinder block and a front end plate. a swash plate disposed in a crank chamber formed between the two and connected to the drive shaft so as to be able to change an inclination angle; and the rotation of the swash plate swings and causes the piston to reciprocate within the cylinder. A rocking plate;
A variable capacity compressor comprising a rotation prevention mechanism for preventing rotation of the oscillating plate, and in which the compression capacity is changed by changing the stroke of the piston by changing the inclination angle of the swash plate, The rotation prevention mechanism includes a columnar block inserted at a predetermined position on the outer periphery of the rocking plate and having a vertical groove formed at the tip thereof, and one side edge of the columnar block is fitted into the vertical groove, and A guide plate is provided at both ends of the front end plate and the cylinder block, and is pivotably fitted into a guide plate insertion hole that is narrow in the center and widens as it goes up and down. A variable capacity compressor is obtained.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

Referring to FIG. 1, a housing 10 has a cylinder block 11 at one end. A plurality of cylinders 12 are formed in the cylinder block 11. The other end of the housing 10 is closed by a front end plate 13, and a crank chamber 14 is formed between the front end plate 13 and the cylinder block 11. Further, a cylinder head 18 is provided on the end face of the cylinder block 11 via a valve plate 17 having a suction hole 15 and a discharge hole 16. The cylinder head 18 is connected to the cylinder 12 through the suction hole 15.
a suction chamber 19 selectively connected to the discharge hole 16;
The suction chamber 20 is selectively connected to the cylinder 12 via a suction chamber 20. 21 and 22 indicate the respective suction valves and discharge valves.

The cylinder head 18 includes a suction chamber 19;
A fluid inlet 23 and a fluid outlet 24 are connected to the discharge chamber 20, respectively, and connected to an external fluid circuit (not shown).

The drive shaft 25 extends from the outside of the front end plate 13 into the crank chamber 14, and is rotatably supported by the front end plate 13 and the cylinder block 11.

Further, a rotor 26 is fixed to the drive shaft 25 and is rotatable together with the drive shaft 25.

A swash plate 27 is hingedly connected to the rotor 26 by a pin 28 . Therefore, the swash plate 27 is rotatable together with the drive shaft 25 as the drive shaft 25 rotates, and since the swash plate 27 is hinged, the angle of inclination with respect to the drive shaft 25 is variable.

A swing plate 29 is rotatably mounted on the end face of the swash plate 27 facing the cylinder block 11. One end of a piston rod 30 is ball-coupled to the outer periphery of the swing plate 29.

A piston 31, which is slidably fitted into the cylinder 12, is ball-coupled to the other end of the piston rod 30.

A radial hole 32 is formed at a lower position on the outer periphery of the rocking plate 29, and a cylindrical block 33 is arranged in the hole 32 so as to be movable in the radial direction of the rocking plate 29. ing.

Referring to FIG. 2, a vertical groove 34 is formed in the cylindrical block 33 in the axial direction from the lower end surface.

3 and 4, a guide plate 3 is provided in the lower part of the crank chamber 14 in parallel with the drive shaft 25.
5 is arranged, and the vertical groove 34 of the cylindrical block 33 is fitted from the upper edge of this guide plate 35. The upper edge of the guide plate 35 has a downwardly convex arc shape 36 as shown in the figure.

Further, both ends of the guide plate 35 are loosely fitted into guide plate insertion holes 37 and 38 formed in the front end plate 13 and the cylinder block 11, respectively, so that the guide plate 35 can swing.

That is, as shown in detail in FIG. 4, the guide plate insertion holes 37 and 38 are formed on opposing surfaces of the cylinder block 11 and the front end plate 13, respectively, so that the width W at the center is slightly larger than the thickness t of the guide plate 35. It is wide and formed into a vertically elongated shape that expands in the vertical direction.

Therefore, the guide plate 35 is inserted into the guide plate insertion hole 3.
It is designed to be able to swing by a predetermined angle using the center portions of 7 and 38 as rotational fulcrums.

In addition, at the bottom of the guide plate insertion holes 37 and 38,
Protrusions 39 and 40 are provided, respectively, and are adjusted so that there is no play (backlash) in the horizontal direction of the guide plate 35 supported between the cylinder block 11 and the front end plate 13.

The cylinder block 11 and the valve plate 1
A communication hole 41 for communicating the crank chamber 14 and the suction chamber 19 is formed in 7 .

A pressure sensitive chamber 42 is formed in the middle of this communication hole 41, and a bellows valve 4 is provided in this pressure sensitive chamber 42.
3 is provided.

The bellows valve 43 opens the valve when the crank chamber pressure introduced into the pressure sensitive chamber 42 becomes higher than a predetermined value (bellows inner pressure).
This is to lower the pressure inside the crank chamber 14.

Note that when the internal pressure of the crank chamber 14 is high, the bottom dead center position of the piston 31 shifts toward the top dead center, and the stroke of the piston 31 becomes small.

That is, the angle of inclination of the swash plate 27 and the swing plate 29 with respect to the drive shaft 25 becomes small (close to a right angle), and the compression capacity becomes small. Conversely, when the internal pressure of the crank chamber 14 is low, the back pressure of the piston 31 is small, so the stroke of the piston 31 becomes large for the opposite reason to the above, and the angle of inclination of the swash plate 27 and the rocking plate 29 becomes large. Therefore, the compression capacity increases. However, the variable capacity compressor described here is just one example, and it goes without saying that the present invention is applicable not only to the scope of the mechanism described above.

Next, the operation of the apparatus shown in the example will be explained.

When the drive shaft 25 is rotated by an external drive source (not shown), the rotor 26 and the swash plate 27 rotate together. However, the swing plate 29 is set to be rotatable relative to the swash plate 27, and
Since the cylindrical block 33 provided on the rocking plate 29 is fitted to the guide plate 35, the rocking plate 29 is prevented from rotating, and therefore only swings by following the slope of the rotating swash plate 27. .

Therefore, the piston rod 30 reciprocates in the axial direction, and the piston 31 reciprocates within the cylinder 12.

At this time, the guide plate 35 has a cylindrical block 3
Since the vertical grooves 34 provided in the guide plate 3 are fitted, the swing plate 29 reciprocates along a convex arc 36 below the guide plate 35.

Fluid is sucked from the suction chamber 19 through the suction hole 15 by the reciprocating movement of the piston 31 within the cylinder 12, and the fluid is compressed and discharged from the discharge hole 16 into the discharge chamber 20. That is, the fluid is compressed.

During the process of suction and discharge of fluid due to the reciprocating motion of the piston 31, fluid flows into the crank chamber 14 from the gap between the piston 31 and the cylinder 12.
That is, blow-by gas exists in the crank chamber 14, and this blow-by gas causes the crank chamber 14 to
internal pressure increases.

As a result, as described above, the inclination of the swash plate 27 and the rocking plate 29 becomes smaller, and the compression capacity becomes smaller. Thereafter, when the internal pressure of the crank chamber 14 becomes equal to or higher than a certain pressure, the bellows valve 43 opens and the crank chamber 14 opens.
4 and the suction chamber 19 communicate with each other. In this way, the internal pressure of the crank chamber 14 decreases, and as described above, the angle of inclination of the swash plate 27 and the rocking plate 29 increases, so that the compression capacity increases.

When assembling the compressor described above, in particular, the rotation prevention mechanism is assembled by inserting the guide plate 35 into the guide plate insertion hole 37 of the cylinder block 11 so that its tip abuts against the protrusion 39, and inserting the guide plate 35 into the crank chamber 14. The cylindrical block 33 is fitted to the upper part of the guide plate 35, and the swing plate 29 and the swash plate 27
The assembly is inserted into the housing 10 while inserting the head of the cylindrical block 33 into the hole 32 of the rocking plate 29.

Thereafter, other parts are assembled into the housing 10, and the guide plate 35 is attached to the housing 10 so that the other end of the guide plate 35 enters the guide plate insertion hole 38 provided in the front end plate 13.

(Effects of the invention) According to the invention, the rotation prevention mechanism of a variable capacity compressor can be achieved by simply inserting the guide plate into the guide plate insertion hole provided in the cylinder block and front end plate in advance. There is no need for the complicated work of assembling a plurality of parts in a predetermined relationship, and the assembly work can be performed extremely easily and the number of parts can be reduced.

In addition, even if the vertical groove of the cylindrical block is inclined with respect to the guide plate due to an assembly error or a gap, the guide plate is supported so that it can swing, so it will follow the inclination. Move. Therefore, as in the case where the guide plate is rotatably supported, uneven contact between the wall surface of the vertical groove and both wall surfaces of the guide plate can be prevented.
This has the effect of maintaining smooth sliding contact between the guide plate and the cylindrical block.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a variable capacity compressor showing an embodiment of the present invention, Fig. 2 is an exploded perspective view of the rotation prevention mechanism shown in Fig. 1, and Fig. 3 shows the installation state of the guide plate shown in Fig. 1. FIG. 4 is a cross-sectional view taken along the line - - in FIG. 3, and FIGS. 5 and 6 are exploded perspective views of the conventional rotation prevention mechanism. DESCRIPTION OF SYMBOLS 10... Housing, 11... Cylinder block, 12... Cylinder, 13... Front end plate, 14... Crank chamber, 25... Drive shaft, 27... Swash plate, 29... Rocking plate, 31... ... Piston, 33 ... Columnar block, 34 ... Vertical groove, 37, 38 ... Guide plate insertion hole.

Claims (1)

[Scope of utility model registration request] A housing having a cylinder block including a plurality of cylinders, a front end plate facing the cylinder block and supporting a drive shaft, and a crank chamber formed between the cylinder block and the front end plate, a swash plate connected to a shaft so that its inclination angle can be changed; a oscillation plate that swings as the swash plate rotates to cause the piston to reciprocate within the cylinder; and a rotation that prevents the oscillation plate from rotating. In the variable capacity compressor, the rotation prevention mechanism is configured to change the compression capacity by changing the stroke of the piston by changing the inclination angle of the swash plate. A columnar block having a vertical groove formed at its tip is inserted into a predetermined position on the outer periphery of the columnar block, one side edge of the columnar block is fitted into the vertical groove, and both ends are connected to the front end plate, respectively. A variable capacity compressor comprising a cylinder block and a guide plate that is swingably fitted into a guide plate insertion hole that is narrow in the center and expands in the vertical direction.