JPH0442556Y2 - - Google Patents

Description

[Detailed Description of the Invention] <<Industrial Application Field>> This invention relates to a gas compressor, and particularly to a gas compressor with variable compression chamber capacity suitable for car coolers.

<Prior Art> Conventionally, this type of gas compressor has been equipped with a control plate between the side block and the compression chamber, and by rotating this control plate, in order to make the capacity of the compression work chamber variable. The gas in the compression chamber is bypassed to the suction chamber through a bypass hole formed in the control plate surface, and the amount of compression of the compressed gas is adjusted.

This control plate is driven by a mechanism as shown in FIG. Note that this figure is a cross-sectional view of the control plate part of the main body of the gas compressor.
The vertical cross-sectional view is similar to FIG. 1, which is a vertical cross-sectional view of a gas compressor according to the present invention, which will be described later, so the explanation will be given below with reference to FIG. 1 as well.

In the figure, an opening 30 having an inner cylindrical shape is formed in the front head 12, and a drive shaft 31 is slidably fitted into this opening 30.
The tip 31a faces into the suction chamber 22, and is always urged toward the rearward side by the spring pressure of the pressing spring 32.

On the other hand, the space 33 on the rear end 31b side of the drive shaft 31
Inside, lubricating oil in an oil reservoir 27 pressurized by the discharge gas pressure is supplied through the oil distribution path 28 and the communication hole 29, and the hydraulic pressure (hydraulic pressure) of this lubricating oil causes the pressure spring 32 to spring. Drive shaft 31 in the opposite direction to the pressure
is energized. Although not shown in the drawings, a constriction part is formed in the communication hole 29 in the middle thereof, and rapid pressure fluctuations in the discharge gas pressure are directly transferred to the space part 33.
It is designed so that it is not transmitted to

Furthermore, the relationship between the drive shaft 31 and the control plate 19 is such that a drive pin 37 is provided protruding from the side surface of the control plate 19 facing the front head 12, and this drive pin 37 is attached to an arcuate guide formed on the front side block 14. The suction chamber 22 passes through the hole 38.
The tip 37a of the pin faces inside, and the tip 37a of the pin is engaged in a recess 39 formed in the drive shaft 31.

Therefore, the total pressure of the spring pressure of the pressing spring 32 and the suction pressure in the suction chamber 23 is applied to the tip 31a of the drive shaft 31, while the rear end 31b of the drive shaft 31 is subjected to the total pressure in the space 33. The hydraulic pressure of the supplied lubricating oil is applied, and the differential pressure between the total pressure and the hydraulic pressure causes the drive shaft 31 to move backward within the opening 30 and drive the control plate 19 to rotate within a predetermined angle via the drive pin 37. I can do it.

A control valve for adjusting oil pressure (hereinafter referred to as "hydraulic control valve") is provided between the suction chamber 22 and the space 33.
40 are provided. This hydraulic control valve 40 is
A chamber 42 is formed in the middle of a passage 41 communicating with the space 33, and the tip of a rod 44 protruding from the movable end of a bellows 43 disposed within the chamber 42 is contained in the passage 41 when the bellows 43 expands. By pressing the ball 45 against the spring 46, the passage 41 is opened and the hydraulic pressure in the space 33 is released to the suction chamber 22 on the low pressure side.

When a gas compressor equipped with the control plate 19 having such a configuration is used, for example, in a car cooler,
Because it is connected to the output shaft of the engine and driven,
When the engine speed increases, the amount of refrigerant compression per unit time increases, the pressure on the discharge side during gas compression increases, and at the same time the pressure on the suction chamber 22 side decreases. Then, the hydraulic pressure control valve 40 is operated in accordance with the fluctuation of the pressure within the suction chamber 22, and the hydraulic pressure within the space 33 is released to the suction chamber 22 side, and the hydraulic pressure within the space 33 is reduced. As a result, the drive shaft 31 is moved back, the control plate 19 is rotated, the compressed gas is bypassed through the bypass hole 19a provided in the control plate 19, and the capacity of the compression work chamber is automatically adjusted to an appropriate value. The amount of refrigerant compression is adjusted to an appropriate level.

However, in this hydraulic control valve 40, the passage 4
1 is blocked by ball 45, ball 45
Since the hydraulic pressure from the space 33 is applied to
In order to open the passage 41, the bellows 43 requires a pushing force sufficient to overcome the hydraulic pressure. For this reason, a problem arises in that the force acting on the ball 45 changes due to changes in the pressure in the space 33 due to the opening and closing operations of the hydraulic control valve 40, making it difficult to precisely adjust the amount of refrigerant compression.

As a solution to these problems, the sixth
A hydraulic control valve 50 as shown in the figure has been proposed. That is, this hydraulic control valve 50 has a chamber 52 in the middle of a communication path 51 that communicates with the space 33.
A bellows 53 whose one end is fixed in the chamber 52 and expands and contracts by external pressure, and a spool-shaped bellows 53 that protrudes from the movable end of the bellows 53 and has a through hole 54 in the middle part of a uniform diameter. A housing part 57 in which a guide hole 56 into which the valve element 55 is slidably fitted is formed, and a through hole 54 when the valve element 55 fitted in the guide hole 56 is projected. An oil passage 58 is formed in the housing part 57 and intersects with the housing part 57 at a position and connects one end to the chamber 52 and the other end to the communication passage 51 which is connected to the space 33 on the rear end side of the drive shaft 31. It is constituted by a hydraulic communication path 59 that is connected to the inner end of the guide hole 56 and an oil reservoir 27 on the compression chamber side in which lubricating oil is stored via an oil distribution path 28.

According to this improved hydraulic control valve 50, when the rotational speed of the rotor 18 increases or the cooling load etc. decreases and the pressure in the suction chamber 22 decreases,
When the bellows 53 inside the chamber 52 expands, the valve body 55 at its tip slides through the guide hole 56 formed in the housing part 57, and the through hole 54 of the valve body 55 opens the oil passage 58 formed in the housing part 57. reaching the
When the hydraulic pressure in the space 33 on the rear end side of the drive shaft 31 is released to the suction chamber 22 side via the chamber 52, the drive shaft 31 moves backward and the control plate 19 rotates in a direction to reduce the amount of compression. .

Furthermore, when the pressure in the suction chamber 22 increases, the bellows 53 in the chamber 52 contracts, and the valve body 55 slides in the return direction, closing the oil passage 58 formed in the housing part 57 and closing the drive shaft 31. As the oil pressure in the rear end side space 33 increases, the drive shaft 31 moves forward, and the control plate 19 rotates in a direction that increases the amount of compression.

Moreover, when the valve body 55 slides, the oil reservoir 2 on the compression chamber side is connected to the tip of the valve body 55 via the hydraulic communication passage 59.
Since the oil pressure of 7 is constantly applied, the valve body 5
The bellows 53 corresponds to the amount pressed by the tip of 5.
By adjusting the internal pressure of the air conditioner, it is possible to change the control pressure depending on the cooling load.

By using this improved hydraulic control valve 50, it is possible to eliminate the influence of the primary pressure in the communication passage 51, that is, the pressure in the space 33, on the opening/closing operation, and as a result, the secondary pressure in the communication passage 51 is reduced. That is, the opening and closing operation of the valve can be obtained substantially proportional to the pressure in the suction chamber 22, and the amount of gas compression can be controlled with high precision.

<<Problems to be Solved by the Invention>> However, when using the conventional improved oil pressure regulating valve 50 described above, the valve body 55 is configured to be able to move approximately in proportion to the pressure in the suction chamber; Since the moving distance of the valve body 55, that is, the stroke, and the amount of lubricating oil flowing out are non-linear, there is a problem in that the amount of gas compression cannot be adjusted more precisely.

That is, since the relationship between the stroke of the valve body 55 and the opening area of the through hole 54 for passing lubricating oil is non-linear as shown by the chain line in FIG. When we first started, there was a problem that the stroke of the valve body became larger than necessary.

<Means for Solving the Problems> This invention was made to solve the above problems, and consists of a cylinder block whose inner circumference is approximately elliptical, and front cylinders attached to both sides of the cylinder block. and a rear side block, a rotor that is rotatably suspended horizontally in a cylinder chamber formed by the cylinder block and both side blocks and has a plurality of vanes that can move forward and backward in the radial direction, and an inner surface of the front side block. a substantially disk-shaped control plate that is provided on the holder and is rotatable within a predetermined angle, and is connected to a drive pin that protrudes from the outer surface of the control plate;
and a drive shaft arranged such that its tip faces into the suction chamber formed between the front side block and a front head provided outside the front side block; a pressure spring that biases the drive shaft in the backward direction; a supply path that supplies lubricating oil from an oil reservoir pressurized by discharged gas or discharged gas pressure to a space on the rear end side of the drive shaft; and the space. and a control valve that is provided in a communication passage that communicates between the suction chamber and the suction chamber, and that opens the communication passage when the pressure in the suction chamber decreases, a chamber that is open to the suction chamber side; a spool-shaped valve body having a small diameter stepped portion formed in the intermediate portion of a uniform diameter and protruding from the movable end of the expandable body, and the valve body is slidable. a housing portion formed with a guide hole that is fitted into the housing portion; an oil passage provided in the housing portion, one end of which is connected to a communicating path that communicates with the space portion, and the other end of which is connected midway through the guide hole; an oil passage chamber that is formed at a connecting portion between the guide hole and the oil passage and communicates with the inside of the chamber through a gap between the small-diameter stepped portion of the valve body and the guide hole when the valve body moves forward; It is characterized by comprising a control valve.

《Operation》 When the rotational speed of the rotor increases or the pressure in the suction chamber decreases due to a decrease in the cooling load, the expandable element in the chamber expands according to the pressure, and the valve element at the tip of the expandable element expands into the housing. It slides through the guide hole formed in the.

As a result, the oil passage chamber communicates with the inside of the chamber through the gap between the small-diameter stepped portion of the valve body and the guide hole. At this time, the opening area of the oil spill path from the space to the chamber increases linearly in proportion to the movement stroke of the valve body, and the amount of lubricating oil flowing from the space to the chamber also increases linearly. do.

On the other hand, when the pressure in the suction chamber increases, the valve body operates in the opposite manner to the above. At this time, the opening area of the oil outflow path as described above naturally decreases linearly in proportion to the movement stroke of the valve body.

Therefore, the drive shaft is driven by the hydraulic pressure in the space adjusted by the hydraulic control valve having the valve body, and the control plate is rotated.

<<Example>> Hereinafter, preferred embodiments of the gas compressor according to the present invention will be described based on the drawings.

FIG. 1 is a vertical cross-sectional view showing the overall configuration of a gas compressor according to this invention, and FIG.
FIG.

The gas compressor shown in these figures includes a compressor main body 10, a casing 11 with an open end that airtightly surrounds the main body 10, and a front head 12 attached to the open end surface of the casing 11. There is.

The gas compressor main body 10 includes a cylinder block 13 having a substantially elliptical inner circumference, and a cylinder block 13 having a substantially elliptical inner circumference.
front side blocks 14 attached to both sides of
and a rear side block 15, and within the generally elliptical cylinder chamber a formed by these, five vanes 17 that are integral with the rotor shaft 16 and are retractable in the radial direction are arranged around the rotor shaft 16. The attached rotor 18, which has a solid cylindrical shape, is horizontally suspended so as to be freely rotatable.

Further, a substantially disc-shaped control plate 19 is rotatably fitted into a boss portion 14a protruding from the inner surface of the front side block 14 via a thrust bearing 20.

Regarding the structure and operation of the mechanism that drives the control plate 19, the same reference numerals are given to the common parts explained in the prior art shown in FIG. The description will be omitted and new parts will be given different symbols.

Characteristic parts of the present invention reside in the housing portion 57 and the valve body 55 of the hydraulic control valve 50. That is, a small-diameter stepped portion 60 is formed approximately in the center of the spool-shaped valve body 55 in the longitudinal direction, and the length of the small-diameter stepped portion 60 is such that the length of the small-diameter stepped portion 60 extends between the oil passage 58 provided in the housing portion 57 and the chamber 52. It is formed to have a communicating length.

In addition, an oil passage chamber 58a is formed in the housing 57 at a connecting portion between the guide hole 56 and the oil passage 58, and this oil passage chamber 58a is opened by the forward movement of the valve body 55 to form a small diameter step of the valve body 55. It is configured to communicate with the inside of the chamber 52 through the space between the portion 60 and the guide hole 56. The size of the oil passage chamber 58a is set to have a larger diameter than the large diameter portion of the valve body 55 and a width slightly larger than the cross-sectional diameter of the oil passage 58.

Valve body 55 and housing portion 57 configured as above
In this case, the valve body 55 is expanded and contracted by the bellows 53.
moves in the direction of the arrow in the figure, and the small diameter stepped portion 6 of the valve body 55
0 is located between the oil passage chamber 58a and the chamber 52, a gap is created between the outer peripheral surface of the small diameter stepped portion 60 and the inner wall surface of the guide hole 56, and an opening 61 is formed. The cross-sectional area of the opening 61 is the product of the stroke of the valve body 55 and the large diameter of the valve body 55, and is therefore proportional to the stroke of the valve body 55, as shown in FIG.

In the gas compressor of this embodiment configured as described above, when the vanes 17 rotate with the rotation of the rotor 18 and gas compression is started, the front Suction chamber 22 sucked in from the intake port 21 provided in the head 12
The gas inside is introduced into an intake passage 24 formed through the cylinder block 13 through an intake hole 23 provided in the front side block 14, and through notches 24a and 24 provided on both sides of this intake passage 24.
It is sucked into the cylinder chamber a from b.

Next, when the vane 17 rotates and enters a compression stroke, the compressed refrigerant gas passes through a discharge port and a discharge valve (not shown), and then passes through a communication hole 25 provided in the rear side block 15 to the rear side block 15.
After the oil is separated there, it reaches the rear space b of the casing 11 as shown by arrow B in FIG. be discharged.

The separated oil, that is, the lubricating oil, is stored in the rear space b.
The oil is stored in the oil reservoir 27 at the lower part of the cylinder block 13 and the vanes 17 through the oil flow path 28 provided in the cylinder block 13 and both side blocks 14 and 15.
The air is supplied to the bottom of the space 33 for lubrication and vane pressure application, and is supplied to the space 33 through the communication hole 29 provided in the front side block 14, that is, through the supply path consisting of these paths and the communication hole. supplied to

Next, the operation of this hydraulic control valve 50 will be explained. That is, when the rotational speed of the rotor 18 increases or the air conditioning load decreases and the pressure in the suction chamber 22 decreases, the bellows 53 in the chamber 52
expands, and the small diameter stepped portion 60 of the valve body 55 at its tip reaches the oil passage chamber 58a formed in the housing 57, and the hydraulic pressure in the space 33 is transferred to the suction chamber 22 side through the opening 61 and the chamber 52. will be opened to At this time, the opening cross-sectional area of the opening 61 is proportional to the stroke of the valve body 55 as shown by the solid line in FIG. can be opened to

As the oil pressure in the space 33 decreases in this way, the drive shaft 31 moves back and the control plate 1
9 rotates in the direction of reducing the compressor.

Also, when the pressure in the suction chamber increases, the chamber 5
As the bellows 53 in 2 shrinks, the valve body 5
5 slides in the return direction, closing the opening 61 and increasing the oil pressure in the space 33, the drive shaft 31
moves forward, and the control plate 19 rotates in a direction that increases the amount of compression.

Next, the gas bypass operation of the control plate 19 will be explained. Bypass holes 19a are provided at the peripheral edge of the control plate 19, facing each other by 180°, and the bypass holes 19a are selectively communicated with the suction holes 23 provided in the front side block 14 and the bypass holes 14a. Ru. As a result, when the pressure in the suction chamber 22 increases during load increase or low-speed operation and the control plate 19 is rotated, the bypass hole 19a of the control plate 19 and the suction hole 23 of the front side block 14 almost coincide with each other. A large amount of refrigerant is supplied from the suction chamber 22 to the cylinder chamber a through the suction hole 23 and the bypass hole 19a, increasing the capacity of the compression working chamber.

On the other hand, when the load is reduced or high-speed operation is performed, the pressure in the suction chamber 23 decreases, and the control plate 19 is rotated in the opposite direction, so that the bypass hole 19a of the control plate 19 and the bypass hole 14a formed in the front side block 14 are rotated. The compressed gas in the cylinder chamber 24 is bypassed into the suction chamber 22 through these bypass holes 19a and 14a, thereby reducing the capacity of the compression working chamber and maintaining the optimum compression amount.

As is clear from the above description, the gas compressor according to the present invention has a spool-like shape having a small-diameter stepped portion 60 in the hydraulic control valve 50 for adjusting the capacity of the compression work chamber in response to fluctuations in load and rotation speed. valve body 5
5, the opening 6 has an opening cross-sectional area in which the primary side pressure in the communication passage 51, that is, the oil pressure in the space 33, is proportional to the stroke of the valve body 55.
1 to the suction chamber 22, the valve can be opened and closed in proportion to the pressure in the suction chamber 22, and the amount of compression can be controlled with high precision.

In the above embodiment, the bellows 53 is used to generate the power to open and close the valve, but this may be replaced with a diaphragm, a piston, or the like.

<<Effects>> In the gas compressor according to this invention, the hydraulic control valve, which is controlled by the pressure in the suction chamber to adjust the compression amount, is composed of a spool-shaped valve body, and the guide path of the valve body is An oil passage chamber is provided at the connection portion between the valve body and the oil passage, and this oil passage chamber is communicated with the inside of the chamber through the gap between the small diameter stepped portion of the valve body and the guide hole when the valve body moves forward. Because of this structure, the opening area of the oil spill path from the space to the chamber increases linearly in proportion to the movement stroke of the valve body, and the amount of lubricating oil flowing from the space to the chamber also increases linearly. Therefore, the control plate can be operated in proportion to the pressure in the suction chamber, and the amount of compression can be controlled with high precision.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view showing an embodiment of the gas compressor according to this invention, Fig. 2 is a sectional view taken along the - line in Fig. 1, Fig. 3 is an enlarged view of the part A in Fig. 2, and Fig. 4 is FIG. 5 is a sectional view of a conventional example, and FIG. 6 is a sectional view of another conventional example. 10... Gas compressor body, 12... Front head, 13... Cylinder block, 14... Front side block, 15... Rear side block, 17... Vane, 18... Rotor, 19...
Control plate, 19a... Bypass hole, 22...
Suction chamber, 27... Oil reservoir, 28... Oil distribution route,
29... Communication hole (supply path), 30... Opening, 31
... Drive shaft, 32 ... Pressure spring, 33 ... Space, 37 ... Drive pin, 50 ... Hydraulic control valve (control valve), 51 ... Communication path, 52 ... Chamber, 5
3... Bellows, 54... Small diameter stepped portion, 55... Valve body, 56... Guide hole, 57... Housing portion, 5
8...Oil passage, 59...Hydraulic communication path, 60...Small diameter stepped portion, 61...Opening.

Claims (1)

[Claims for Utility Model Registration] A cylinder block with a substantially elliptical inner circumference, front and rear side blocks attached to both sides of the cylinder block, and a rotating cylinder inside the cylinder chamber formed by the cylinder block and both side blocks. a rotor that is freely suspended horizontally and has a plurality of vanes that can move forward and backward in the radial direction;
A substantially disk-shaped control plate is provided on the inner surface of the front side block and is rotatable within a predetermined angle, and the control plate is connected to a drive pin protruding from the outer surface of the control plate, and its tip is connected to the front side block. a drive shaft arranged so as to face into a suction chamber formed between the block and a front head provided on the outside of the front side block;
A pressure spring is arranged at the tip side of the drive shaft and urges the drive shaft in the backward direction, and a space at the rear end side of the drive shaft is used to supply lubricating oil in an oil reservoir pressurized by the discharged gas or discharged gas pressure. In a gas compressor, the gas compressor is equipped with a supply path for supplying the space to the suction chamber, and a control valve that is provided in the communication path that communicates between the space and the suction chamber, and opens the communication path when the pressure in the suction chamber decreases. a chamber that is open to the side; an expandable element provided within the chamber that expands and contracts due to external pressure; and a spool-like spool with a small-diameter stepped portion formed in the intermediate portion of a uniform diameter that protrudes from the movable end of the expandable element. a valve body; a housing portion in which a guide hole into which the valve body is slidably fitted is formed; a communication passage provided in the housing portion, one end of which is connected to the space, and the other end of which is connected to the guide hole; The oil passage is formed in the connecting part between the guide hole and the oil passage, and is formed between the small diameter stepped portion of the valve body and the guide hole by the forward movement of the valve body. A gas compressor comprising: an oil passage chamber communicating with the inside of a chamber; and a control valve.