JPH0445678B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a vane compressor used in vehicle air conditioners and the like.

(Prior art and its problems) Conventionally, vanes have been fitted into vane grooves formed in the radial direction on the circumferential surface of the rotor so as to be able to move forward and backward, and whose tips can slide against the inner circumferential wall of the cam ring, and the discharge capacity can be varied. Controllable vane compressors are known, for example as disclosed in US Pat. No. 4,050,263.

In such a conventional vane, a locking member is provided at the base end of the vane (end on the rotor center side), and a solenoid provided on the side block is activated as necessary to lock the locking member and lock the vane. By keeping the tip of the cam ring spaced apart from the inner circumferential surface of the cam ring, the discharge volume can be variably controlled.

Therefore, there were problems such as a complicated structure, a large number of parts, and high costs.

(Object of the Invention) The present invention has been made in view of the above circumstances, and has a simple configuration, a small number of parts, easy processing and assembly, and no spring wear or "settling". Furthermore, it is an object of the present invention to provide a vane type compressor which is inexpensive and whose discharge capacity can be easily variably controlled to a desired state.

(Means for Solving the Problem) In order to solve the above-mentioned problem, the present invention responds to the ambient temperature of the vane and forces the vane toward the center of the rotor when the ambient temperature exceeds a predetermined value. fixing one end of a shape-memory alloy spring to the base end of the vane, the spring being moved and held in a state where the tip thereof is spaced apart from the inner circumferential wall of the cam ring;
Further, the other end of the spring is extended along the vane groove toward the center of the rotor and fixed to a member at the center of the rotor.

(Example) Hereinafter, one example of the present invention will be described based on the drawings.

1 in Figures 1 and 2 is the compressor housing;
A cylindrical case 2 with one end open, and a bolt 3 attached to one end of the case 2 so as to close the opening.
It consists of a front head 4 attached at. A gas discharge port 5 as a heat medium is provided on the top surface of the case 2, and a gas suction port 6 is provided on the top surface of the front head 4.

A compressor main body 7 is housed inside the housing 1 . The compressor main body 7 includes a cam ring 8,
A front side block 9 and a rear side block 10 are attached to both open ends of the cam ring 8 so as to close the opening surfaces, a rotor 11 rotatably housed inside the cam ring 8, and the rotor 1.
The main component is a rotating shaft 12 of 1, which is formed by screwing a solid member 12a and a hollow member 12b at substantially intermediate positions, and is provided on the front head 4 and both side blocks 9, 10. It is supported by bearings 13 and 14, respectively. The cam ring 8
The inner peripheral surface of the cam ring 8 has an elliptical shape as shown in FIG.
15 are defined. The rotor 11 is provided with a plurality (for example, four) of vane grooves 16 extending in the radial direction at equal intervals in the circumferential direction, and vanes 17 ₁ , 17 ₂ , 17 ₃ , 17 are installed in these vane grooves 16 . ₄ are fitted so that they can move forward and backward along the radial direction.
A back pressure chamber 18 is defined between the bottom of each vane groove 16 and the base end of the vane 17, respectively.

The tip of the vane 17 can slide against the inner circumferential wall of the cam ring 8. The first to third vanes 17 1 to ₁₇ except for the fourth vane 17 ₄
A predetermined number of pieces (two pieces in this example) are attached to the base end of 17 _3.
One end of a coiled spring 19 made of a shape memory alloy is fixed, and the other end of the spring 19 is connected to the vane groove 1.
6 toward the center of the rotor 11, and is fixed to the peripheral wall of the hollow member 12b of the rotating shaft 12, which is a member at the center of the rotor 11. The spring 19 is sensitive to the ambient temperature of the vanes ₁₁ to ₁₇₃ (temperature of the rotor 11), and when the ambient temperature is below a predetermined value, almost no spring force is applied, and when the ambient temperature is above the predetermined value, When the shape is restored, a spring force acts to forcibly move the vanes 17 ₁ to 17 ₃ toward the center of the rotor 11 and keep their tips spaced apart from the inner circumferential wall of the cam ring 8. It is.

The transformation temperatures (this determines the temperature at which the shape is restored) of these springs 19 are set to be different from each other. That is, the first to third vanes 17
The transformation temperatures of springs 19 ₁ to 17 ₃ are set higher in order.

A back pressure communication groove 20 is provided on the sliding surface of the front side block 9 and the rear side block 10 with respect to the rotor 11.
is in communication with the back pressure chamber 18. The front side block 9 is provided with suction holes 21, 21 located on the outer peripheral side of the back pressure communication grooves 20, 20. A suction chamber 2 between the front head 4 and the front side block 9 is inserted through these suction holes 21.
2 and the compression chamber 15 are in communication with each other. Discharge holes 23, 23 are bored in both peripheral walls of the cam ring 8, and a discharge chamber 24 inside the case 2 and the compression chamber 15 communicate with each other via these discharge holes 23. A discharge valve 25 and a discharge valve stop 25a are provided in these discharge holes 23, 23, respectively. The side blocks 9 and 10 are provided with passages 26 and 27 for shaft lubrication, one end of which opens into bearings 13 and 14, and the other end of which opens into the outer peripheral surfaces of both side blocks 9 and 10, respectively. still,
12a in FIG. 1 is a shaft seal member.

(Function) Next, the function of the vane compressor having the above structure will be explained with reference to the discharge capacity characteristic diagram shown in FIG. When the rotating shaft 12 is rotated in relation to the engine of the vehicle and _the rotor ₁₁ rotates in the direction of the arrow in FIG. Due to back pressure and centrifugal force caused by leakage from the vane groove 16, the vane protrudes radially from the groove 16, and its tip surface slides against the inner circumferential surface of the cam ring 8, rotating while maintaining airtightness between the compression chambers 15 and 15. Gas, which is a heat medium, is sucked into the compression chamber 15 through the suction port 6, suction chamber 22, and suction hole 21 in the suction stroke to expand the volume of the compression chamber 15, and the gas is sucked in the compression stroke to reduce the volume of the compression chamber 15. The compressed gas is compressed, and in the discharge stroke at the end of the compression stroke, the compressed gas is delivered to the discharge hole 23, the discharge valve 25, the discharge chamber 24, and the discharge port 5.
The heat exchanger circuit of the air conditioner (not shown) is sequentially supplied to the heat exchange circuit of the air conditioner (not shown).

As the rotation of the rotor 11 increases, the vane ambient temperature (temperature of the rotor 11) increases proportionally, and when the ambient temperature reaches the transformation temperature of the spring 19 of the first vane ₁₇₁ , the vane ambient temperature increases proportionally. Since only the spring 19 recovers its shape, its spring force causes the first
Vane 17 ₁ of rotor 1 resists centrifugal force and back pressure.
The cam ring 8 is forcibly moved toward the center of the cam ring 8, and its tip is held apart from the inner circumferential surface of the cam ring 8. In this state, during one rotation of the rotor 11, the distance between the second vane 17 ₂ and the third vane 17 ₃ and between the third vane 17 ₃ and the fourth vane 17 ₄
Only the two space portions between the second vane 17 _and the second vane constitute a sealed space and the compressor action is performed.
The space between the rear side in the rotational direction and the front side in the rotational direction of the fourth vane ₁₇₄ is not partitioned by the first vane ₁₇₁ and is in a state of direct communication.
Since the suction hole 21 or the discharge hole 23 always communicates with the space, a closed space is not formed, and therefore no compression action is performed. That is, the compression action is performed only during 1/2 of one revolution of the rotor 11, and no compression action is performed during the remaining 1/2 revolution (point a in FIG. 3).

Next, when the rotation of the rotor 11 further increases and its temperature rises to reach the transformation temperature of the second vane 17 ₂ , the second vane 17 ₂ changes as in the case of the first vane 17 ₁ . The cam ring 8 is forcibly moved toward the center of the rotor 11, and its tip is held apart from the inner circumferential surface of the cam ring 8. In this state,
During one rotation of the rotor 11, only the space between the third vane 17 ₃ and the fourth vane 17 ₄ constitutes a closed space and a compression action is performed, but the rotation of the third vane 17 ₃ The space between the rear side in the rotational direction and the front side in the rotational direction of the fourth vane 17 ₄ is not divided by the first and second vanes 17 ₁ and 17 ₂ and is in direct communication with the suction hole 21 at all times.
Alternatively, since the discharge holes 22 communicate with each other, a closed space is not formed and therefore no compression action is performed. That is, the compression action is performed only during approximately 1/4 of one revolution of the rotor 11, and no compression action is performed during the remaining approximately 3/4 revolution (point b in FIG. 3).

Furthermore, when the rotation of the rotor 11 increases and its temperature reaches the transformation temperature of the third vane 17 ₃ , _the third vane 17 3 changes as in the case of the first and second vanes 17 ₁ and 17 ₂ described above. is forcibly moved toward the center of the rotor 11, and its tip is held apart from the inner peripheral surface of the cam ring 8. In this state, only the tip of the fourth vane ₁₇₄ is in sliding contact with the inner circumferential surface of the cam ring 8, so no compression action is performed at all (point c in FIG. 3).

In the above embodiment, a case has been described in which the transformation temperature of the springs 19 of the first to third vanes 17 _{1 to} 17 ₃ is set higher in sequence, but the present invention is not limited to this. The transformation temperature of the spring 19 is made lower than that of the spring 19 of the third vane 17 ₃ , and the transformation temperature of the spring 19 of the third vane 17 ₃ is made lower than that of the spring 19 of the second vane 17 ₂ .
The setting order of the transformation temperature may be arbitrarily changed depending on the desired variable capacitance characteristics, such as setting the transformation temperature smaller than that of No. 9. Furthermore, the present invention is not limited to the type provided with four vanes as shown in the above-mentioned embodiments, but can be implemented as long as it has two or more vanes.

Further, the transformation temperature of each of the springs may be made the same. If this is done, for example, when the ambient temperature of the vane becomes abnormally high (for example, 120°C or higher), each vane will be able to transform the rotor at the same time. In order to move to the center side and quickly bring the load to an unloaded state, it has a safety function to prevent rotor seizure, etc., and is equipped with an abnormal temperature detection switch like the conventional one, so that when the temperature reaches an abnormal temperature, There is no need to provide a safety circuit to shut down the operation by turning off the magnetic switch.

(Effects of the Invention) As detailed above, the vane compressor of the present invention has the following features:
A shape memory alloy that is sensitive to the ambient temperature of the vane and forcibly moves the vane toward the center of the rotor when the ambient temperature exceeds a predetermined value to maintain its tip in a state separated from the inner circumferential wall of the cam ring. One end of a spring made of aluminum is fixed to the base end of the vane, and the other end of the spring is extended along the vane groove toward the center of the rotor and fixed to a member at the center of the rotor. That is.

Therefore, the structure is simple and the number of parts is small, and it is easy to process and assemble, and the spring does not wear out or "sag." Furthermore, it is easy to adjust the discharge capacity to the desired state while being inexpensive. It can be variably controlled.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, FIG. 1 is a longitudinal side view of a vane type compressor, and FIG. 2 is a side view of the vane compressor.
A sectional view taken along the line and FIG. 3 are action explanatory views. 8...Cam ring, 11...Rotor, hollow member (member at the center of the rotor)...12b, 16...
Vane groove, 17 ₁ to 17 ₄ ... Vane, 19 ... Spring.

Claims (1)

[Scope of Claims] 1. A vane type compressor equipped with a vane that is fitted in a vane groove formed in a radial direction on the circumferential surface of a rotor so as to be able to move forward and backward, and whose tip can come into sliding contact with an inner circumferential wall of a cam ring, Shape memory that responds to the ambient temperature of the vane and forcibly moves the vane toward the center of the rotor when the ambient temperature exceeds a predetermined value and maintains its tip in a state separated from the inner circumferential wall of the cam ring. One end of the alloy spring is fixed to the base end of the vane, and the other end of the spring is extended along the vane groove toward the center of the rotor and fixed to a member at the center of the rotor. A vane type compressor featuring: 2 the springs are provided corresponding to the vanes, respectively;
2. A vane compressor according to claim 1, wherein the springs have different transformation temperatures.