JPH05106576A - Multi-cylinder sealed type rotary compressor - Google Patents

Abstract

PURPOSE:To reduce the load on a drive shaft when a compressor is to be started by furnishing a blade spring on one of a plurality of blades to be in slide contact with a plurality of rollers, and performing the compressing motion only with the cylinder provided with blade spring at the time of starting. CONSTITUTION:A drive shaft 2 has a plurality of eccentric parts 2a-2c fitted with respective cylinders 4a-4c, between which middle plates 51, 52 are interposed. A compressing element 3 is formed by forming these cylinders 4a-4c in a single piece construction wherein they are held pinched by a front head 31 and a rear head 32, and is accommodated in an enclosed casing 21. The cylinders 4a-4c accommodate rollers 33, with which a plurality of blades 6a-6c slidable in the radial direction are put in slide contact. In this compressor, a blade spring 7 is installed on only one of the blades 6a-6c, for example the one 6b, and at the time of starting, the compressing motion shall be performed only with its corresponding cylinder 4b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION A drive shaft having a plurality of eccentric parts in an axial direction in a closed casing, a plurality of cylinders in which these eccentric parts are located, and a middle plate interposed between the cylinders. The present invention relates to a multi-cylinder hermetic rotary compressor having a compression element having a front head and a rear head that sandwich each cylinder.

[0002]

2. Description of the Related Art Conventionally, in this type of multi-cylinder hermetic rotary compressor, as shown in FIG. 8, a plurality of cylinders S are laminated with a middle plate M interposed therebetween. A compression element CP, which is formed by arranging a front head F and a rear head R so as to sandwich each of these cylinders S, is housed inside a closed casing C.
A plurality of eccentric parts P formed on the drive shaft K are respectively installed in the cylinder chambers S1 of the cylinders S of P through the rollers G, and the cylinder chambers S1 of the cylinders S are arranged on the suction side and the discharge side. Blades B for partitioning into and are respectively slidably provided, and a blade chamber A for accommodating a blade spring BS is formed on the back side of each blade B, and the tip end portion of the blade B is moved by the blade spring BS. It was done like pressing G.

[0003]

However, in the conventional multi-cylinder hermetic rotary compressor, since the blade springs BS are arranged on the back side of each blade B,
When the compressor is started, each blade B is pressed against the roller G by the blade spring BS, so that the eccentric rotation of the roller G caused by the rotation of the drive shaft K causes the cylinder chambers S1 and C3 to rotate. Since the gas refrigerant sucked into S1 is compressed, there is a problem that the starting torque received by the drive shaft K becomes very large.

Further, conventionally, there is known a multi-cylinder hermetic rotary compressor of this type in which the capacity is controlled by controlling the compression operation of at least one of the plurality of cylinders. .. That is, this compressor is described in, for example, Japanese Utility Model Laid-Open No. 1-144492, and
As shown in FIG. 9, of the blades B, a protrusion D is formed on one side in the axial direction of the blade chamber A side end of one blade B, and the front side of the protrusion D is inside the casing C. Of the blade chamber A and the back side of the blade chamber A are connected to a low pressure region via a pressure adjusting passage E having a pressure adjusting valve F. The pressure adjusting valve F is opened, By connecting the back side of the blade chamber A to the low pressure region, the blade B is held in the retracted position by the action of high pressure acting on the front side of the protrusion D, and the roller is rotated by the rotation of the drive shaft K. The capacity is controlled so that G does not come into contact with the blade B, that is, it does not exert a compression action.

However, although the capacity can be controlled by the conventional compressor as described above, at the time of starting the compressor, the inside of the casing C is in a low pressure state, so the pressure adjusting valve F is opened. Since there is no pressure difference between the back side of the blade chamber A and the front side of the protrusion D even when the back side of the blade chamber A is communicated with the low pressure region, the blade B cannot be held in the retracted position. The blade spring BS is moved forward by the urging force of the blade spring BS to come into contact with the roller G, and the compression operation is performed in the cylinder chamber S1. Therefore, even if the capacity can be controlled as described above, there is a problem that the capacity cannot be controlled at the time of startup and the load at the time of startup cannot be reduced. There is a problem that the pressure must be constantly controlled by the pressure regulating valve F.

The present invention has been made in view of the above problems, and an object thereof is to provide a multi-cylinder hermetic rotary compressor capable of reducing the starting torque of the drive shaft at the time of starting the compressor. It is in. In addition, the vertical multi-cylinder hermetic rotary compressor that enables capacity control operation while enabling capacity control not only at startup but also during operation to reduce drive shaft startup torque is also provided. Especially.

[0007]

According to the multi-cylinder hermetic rotary compressor of claim 1, the hermetic casing 1 is provided with a drive shaft 2 having a plurality of eccentric portions 2a, 2b, 2c in the axial direction.
And a plurality of cylinders 4a, 4b, 4c in which the eccentric portions 2a, 2b, 2c are located, and the cylinders 4a, 4c.
In a multi-cylinder hermetic rotary compressor in which middle plates 51 and 52 interposed between b and 4c and a compression element 3 including a front head 31 and a rear head 32 that sandwich each of the cylinders 4a, 4b and 4c are installed. A discharge pipe 15 for discharging the compressed gas in the casing 1 to the outside is connected to the closed casing 1, and the cylinders 4a, 4b, 4 are connected.
A plurality of blades 6 that come into contact with a plurality of rollers 33, ...
The blade spring 7 is provided in one of the blades a, 6b, 6c, and the back side of each blade 6a, 6b, 6c is opened in the casing 1.

Further, in the multi-cylinder hermetic rotary compressor according to claim 1, a discharge pipe 15 connected to the hermetic casing 1 is provided.
In addition, it is preferable to provide a pressure adjusting valve P that opens when the pressure inside the casing 1 rises to a predetermined pressure and allows the discharge pipe 15 to flow.

Further, in the multi-cylinder hermetic rotary compressor according to claim 1, the blade spring 7 is provided with a rear surface of the blade 6b in the cylinder 4b located at the axial center of the plurality of cylinders 4a, 4b, 4c. It may be arranged on the side.

Further, in the multi-cylinder hermetic rotary compressor according to the second aspect of the present invention, the hermetic casing 1 has a drive shaft 2 having a plurality of eccentric portions 2a, 2b, 2c in the axial direction.
And a plurality of cylinders 4a, 4b, 4c in which the eccentric portions 2a, 2b, 2c are located, and the cylinders 4a, 4c.
In a multi-cylinder hermetic rotary compressor having middle plates 51, 52 interposed between b and 4c, and a compression element 3 having a front head 31 and a rear head 32 for sandwiching the cylinders 4a, 4b, 4c, The drive shaft 2 and the compression element 3 are arranged in the vertical direction, and each cylinder 4a, 4
By contacting a plurality of rollers 33, ...
The freon head in which the blade spring 7 is disposed on one of the plurality of blades 6a, 6b, 6c that slides as the rollers 33 ... Rotate, while the other blades 6a, 6b face each other. 31 or the middle plate 51
Is provided with hooks 8 which are reciprocally movable with respect to the blades 6a and 6b.
The hooks 8 and 8 are formed with hook locking portions 82 and 82 which can be locked at the retracted positions of the blades 6a and 6b, and the back side of the hooks 8 and 8 is formed in the cylinder 4c having the blade spring 7. It communicated with the low-pressure gas region.

A multi-cylinder hermetic rotary compressor according to a fourth aspect of the present invention is a cylinder 4 having the blade spring 7.
It is preferable to provide the solenoid valve 10 in the communication passage 9 that communicates the region of the low pressure gas in c with the back side of the hooks 8, 8.

[0012]

As described above, in the multi-cylinder hermetic rotary compressor according to the present invention, in the first invention according to claim 1, since the inside of the hermetic casing 1 is in a low pressure state at the time of starting, each blade is The pressure on the back side of 6a, 6b, 6c is low, and at the time of starting, each eccentric portion 2a, 2 of the drive shaft 2 is
By the eccentric rotation of b and 2c, each of the blades 6a and 6c
b and 6c start to slide, and only the blade 6b having the blade spring 7 is biased by the blade spring 7 and repeatedly slides in conjunction with the eccentric rotation of the eccentric portion 2b. Cylinder 4b with
Since the refrigerant gas is compressed only inside, the blade springs 7 are not provided on the back side of the other blades 6a and 6c, so that the springs 7 are not biased by the springs. And the blades 6a, 6
Since the pressure on the back side of c is low, the rollers 33, 33 once slide to the retracted position with the eccentric rotation and stop at this retracted position. Therefore, the eccentric parts 2a and 2c run idle and no compression action occurs, and the compression of the refrigerant gas is performed only by the cylinder 4b having the blade spring 7. By doing so, when the compressor is started, the compression operation is performed only in the cylinder 4b having the blade spring 7, the load of the drive shaft 2 at the time of start is reduced, and the starting torque of the drive shaft 2 is reduced accordingly. Is done.

When the pressure inside the casing 1 rises due to the operation of the compressor, the blades 6a and 6c are pushed by the back pressure toward the rollers 33 and 33 and start to slide toward the center of the shaft, and the rollers 6a and 6c start sliding. Since it reciprocates following the eccentric rotation of 33, compression operation with a capacity of 100% is performed. Further, despite the multi-cylinder, each blade 6
The blade spring 7 is attached to one of a, 6b and 6c.
Since the number of parts is reduced, the number of assembling steps is reduced, and in the blades 6a and 6c in which the blade spring 7 is eliminated, the friction between the tip of the blade and the roller 33 is reduced. The efficiency is improved accordingly.

Further, as described in claim 2, the discharge pipe 15 connected to the closed casing 1 is opened when the pressure in the casing 1 rises to a predetermined pressure,
By providing the pressure adjusting valve P that allows the discharge pipe 15 to flow, the discharge pipe 15 can be closed at the time of starting the compressor to make the inside of the casing 1 in a sealed state, and the compressor can be started. Even if only one cylinder is started at a time, the inside of the closed casing 1 is hermetically sealed, so that the pressure in the casing 1 rises faster, and the start-up becomes faster despite the start of one cylinder.

Further, as described in claim 3, the blade spring 7 is provided with a plurality of cylinders 4a, 4b, 4c.
When the drive shaft 2 is arranged on the back side of the blade 6b of the cylinder 4b located at the central portion in the axial direction, a torque is generated in the central cylinder 4b when the drive shaft 2 rotates, and a reaction against the torque is generated. Since the force can be evenly shared by the bearings of the front head 31 and the rear head 32, the reliability of the compressor can be improved.

Further, in the multi-cylinder hermetic rotary compressor of the second aspect of the present invention, when the drive shaft 2 starts to rotate due to the activation of the compressor, the eccentric portion 2a of the drive shaft 2, By the eccentric rotation of 2b and 2c, each blade 6
a, 6b, 6c slide, the blade 6c having the blade spring 7 repeatedly slides in conjunction with the eccentric rotation of the eccentric portion 2c, and compresses the refrigerant gas in the cylinder 4c having the blade 6c. On the other hand, since the inside of the closed casing 1 is in a low pressure state at the time of start-up, there is almost no pressure difference between the tip side and the back side of the hooks 8, 8 and the hooks 8, 8 are When the blades 6a and 6b come into contact with each other and retract, the hooks 8 and 8 drop into the hook locking portions 82 and 82 and are locked, so that the blades 6a and 6b are securely stopped at the retracted position. Of. Therefore, the eccentric portions 2a, 2
There is no compression of refrigerant gas due to idling of b. At this time, the cylinder 4c having the blade spring 7
Is compressed by the reciprocating movement of the blade 6c by the blade spring 7, and this compression is performed only by the cylinder 4c. As a result, at the time of starting the compressor, the compression operation is performed only in the cylinder 4c, so that the load on the drive shaft at the time of starting can be reduced.

When the pressure in the casing 1 rises due to the operation of the compressor, the back sides of the blades 6a and 6b having the hooks 8 and 8 also rise, and the hook 8 communicating with the back side. While the tip side of 8 is high pressure,
Since the back side of the hooks 8, 8 communicates with the low-pressure suction passage 11 and has a low pressure, the pressure difference causes the hooks 8, 8 to be pushed toward the low-pressure side to move, thereby locking the hooks. The blades 6a, 6b slide toward the center in the axial direction due to the high pressure acting on the rear surface, and thereafter follow the eccentric rotation of the roller 33. It reciprocates to perform compression operation with a capacity of 100%.

Further, in the multi-cylinder hermetic rotary compressor according to the second aspect of the present invention, solenoid valves 10, 10 are provided in the communication passage 9, and one or both of these solenoid valves are provided. By operating the hooks 8 and 8 in the closed state, the back side of the hooks 8 and 8 can be made to have a high pressure. It is possible to lower 81 and engage with the hook engaging portions 82, 82. Therefore, the blade 6 is locked by the hooks 8 and 8 being locked.
Since the sliding of a and 6b can be stopped, the capacity can be controlled by opening and closing the solenoid valves 10 and 10.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the multi-cylinder hermetic rotary compressor shown in FIG. 1, a motor M is arranged on the upper side inside the hermetic casing 1, and a compression is rotatably driven by a drive shaft 2 extending from the motor M on the lower side. The element 3 is provided. The drive shaft 2 has an axial direction,
The compression element 3 is provided with a plurality of eccentric parts 2a, 2b, 2c, and the compression element 3 has cylinders 4a, 4b having a plurality of cylinder chambers 41a, 41b, 41c in which the eccentric parts 2a, 2b, 2c are located. , 4c and the cylinders 4a, 4
The cylinder chambers 41a, 41b, 41c are constituted by middle plates 51, 52 interposed between the cylinder chambers b, 4c and front and rear heads 31, 32 arranged at the upper and lower portions of the cylinders 4a, 4b, 4c. A roller 3 into which the eccentric portions 2a, 2b, 2c of the drive shaft 2 are fitted inside the roller 3
3 ..., and the cylinders 4a, 4
blades 6a, 6 which come into contact with the rollers 33, ... And b and 4c and slide by the eccentric rotation of the rollers 33 ,.
.. for accommodating the b, 6c are formed, and the blades 6a, 6b, 6 for accommodating the sliding grooves 71 ,.
The cylinders 41a, 41b, 41c are divided into low pressure side and high pressure side by c, and the gas refrigerant sucked in the cylinder chambers 41a, 41b, 41c by the eccentric rotation of the rollers 33 ,. Is compressed, and the compressed gas refrigerant is discharged from a discharge passage (not shown) formed in the compression element 3 to a discharge space H in the casing 1.

In addition, the cylinders 4a, 4b, 4c are formed with suction passages 11 ... Connecting the suction pipes 14 ... And the suction passages 11 ... Cylinder chamber 4
The low pressure gas refrigerant is sucked into 1a, 41b and 41c, while the casing 1 is connected with a discharge pipe 15 for discharging the compressed gas refrigerant inside the casing 1 to the outside.

In the multi-cylinder hermetic rotary compressor described above, however, the plurality of rollers 33, ... Installed in the cylinders 4a, 4b, 4c are brought into contact with the rollers 33 ,.
... A plurality of blades 6a, 6 that slide with the rotational drive of
The blade spring 7 is disposed in one of the cylinders b and 6c, and in the embodiment shown in FIG. 1, the blade in the cylinder 4b of the plurality of cylinders 4a, 4b and 4c located at the central portion in the axial direction. The blade spring 7 is provided only on the back side of 6b. At this time, the back surface side of each of the blades 6a, 6b, 6c housed in each of the sliding grooves 71 is open to the discharge space H, and each of the back surfaces increases with the gas pressure in the discharge space H. I am doing it as it is urged.

Moreover, the discharge pipe 15 is provided with a pressure adjusting valve P which opens when the pressure in the casing 1 reaches a predetermined pressure and allows the discharge pipe 15 to flow. That is, when the compressor is in a low pressure state at startup, the discharge pipe 15 is closed and the compression element 3 is closed.
The discharge gas discharged from is prevented from flowing out.

Thus, according to the above-mentioned multi-cylinder hermetic rotary compressor, since the inside of the hermetic casing 1 is in a low pressure state at the time of starting, at the time of starting, the blades 6a, 6b, The pressure on the back side of 6c is low, and when the drive shaft 2 starts to rotate due to the start of the compressor, the eccentric rotation of the eccentric portions 2a, 2b, 2c of the drive shaft 2 causes
The blades 6a, 6b, 6c start sliding, and the central blade 6b having the blade spring 7 is
Since the blade spring 7 is biased, the sliding is repeated in conjunction with the eccentric rotation of the eccentric portion 2b to compress the refrigerant gas in the central cylinder 4b.
On the other hand, since the blade spring 7 is not disposed on the back side of each of the upper and lower blades 6a, 6c, the blades 7 are not biased by the springs 7 and the back surfaces of the blades 6a, 6c are not affected. Since the pressure on the side is low, the rollers 33, 33 once slide to the retracted position with the eccentric rotation of the rollers 33, and stop at this retracted position. Therefore, the eccentric portions 2a and 2c run idle and no compression action occurs, and the compression of the refrigerant gas is performed only by the central cylinder 4b. By doing so, at the time of starting the compressor, the compression operation is performed only in the central cylinder 4b.
The load on the drive shaft 2 at the time of start-up can be reduced, and that much drive shaft 2
The starting torque of can be reduced.

When the pressure in the casing 1 rises due to the operation of the compressor, the blades 6a, 6c
Since the back side of the blade communicates with the high pressure discharge space H in the casing 1, a high pressure acts on the back side of the blade, and the blades 6a and 6c are pushed by the back pressure to the rollers 33 and 33 side. 6a and 6c slide toward the shaft center and thereafter reciprocate following the eccentric rotation of the roller 33 to perform a compression operation with a capacity of 100%.

Further, in the above-mentioned embodiment, the pressure adjusting valve P is provided in the discharge pipe 15, and the pressure adjusting valve P is provided in the discharge pipe 15, and the rear side of the valve body P1. Spring P2 is attached to the discharge pipe 1
5 is attached to the mounting portion P3 formed in
When the internal pressure reaches a predetermined pressure, the spring P2 is pressed by the compressed gas so as to contract, and the valve body P1 is seated when the inside of the discharge pipe 15 is in a low pressure state lower than the predetermined pressure. By forming the valve seat P4 in the discharge pipe 15 and closing the discharge pipe 15 at the time of starting the compressor to make the inside of the casing 1 in a hermetically closed state, only one cylinder at the time of starting the compressor. Even if it is started, the sealed casing 1 is sealed, so that the pressure in the casing 1 can be increased faster, and the start-up can be made faster in spite of the start of one cylinder.

The blade spring 7 may be provided in any cylinder, but as shown in FIG. 1, the central portion of the front head 31 and the rear head 32, which is an intermediate position with respect to each bearing portion, is provided. By disposing it in the cylinder 4b, a torque is generated in the central cylinder 4b when the drive shaft 2 rotates, and a reaction force against this torque is evenly shared by the bearings of the front head 31 and the rear head 32. Therefore, the reliability of the compressor can be improved. In addition, the multi-cylinder hermetic rotary compressor described above requires only the blade spring 7 to be arranged on one of the blades 6a, 6b, and 6c in spite of having three cylinders. With respect to the blades 6a and 6c without the blade spring 7, the friction between the tip end of the blade and the roller 33 can be reduced, and the efficiency can be improved accordingly.

Although the vertical compressor has been described in the above embodiment, the present invention can be applied to a horizontal compressor.

Next, another embodiment will be described with reference to the drawings. The multi-cylinder hermetic rotary compressor shown in FIG. 2 is a vertical compressor, and has a hermetic casing 1 similar to the above embodiment.
The motor M is disposed on the upper side of the inside of the
A compression element 3 is provided which is rotatably driven by a drive shaft 2 extending from. The drive shaft 2 has a plurality of eccentric parts 2 in the axial direction.
a, 2b, 2c, and the compression element 3
Is a cylinder 4 having a plurality of cylinder chambers 41a, 41b, 41c in which the eccentric portions 2a, 2b, 2c are located.
a, 4b, 4c, middle plates 51, 52 interposed between the cylinders 4a, 4b, 4c, and front and rear heads 31, 32 arranged at upper and lower portions of the cylinders 4a, 4b, 4c. The cylinders 41a, 41b, 41c are internally provided with rollers 33, ... Into which the eccentric portions 2a, 2b, 2c of the drive shaft 2 are inserted, and the cylinders 4a, 4b ,. 4c is formed with sliding grooves 71 ... For accommodating the blades 6a, 6b, 6c which come into contact with the rollers 33, ... And slide by the eccentric rotation of the rollers 33. Each of the cylinder chambers 41a, 41b, 41c is divided into a low pressure side and a high pressure side by the blades 6a, 6b, 6c, and the eccentric rotation of the rollers 33, ... At 41c Compressing the incoming refrigerant, so that ejected to the discharge space H in the casing 1 from the discharge passage to form the compressed refrigerant into said compression element 3 (not shown).

The upper and lower cylinders 4a,
The suction passages 11, 11 connecting the suction pipes are formed in 4c, and the suction passages 1 are formed in the middle plates 51, 52, respectively.
Guide passages 13 and 13 for guiding the gas refrigerants 1 and 11 to the suction port 12 of the central cylinder 4b are formed so that the suction passages 11 and 11 and the suction port 12 lead to the cylinder chambers 41a, 41b and 41c. The low-pressure gas refrigerant is drawn in.

Thus, in the vertical multi-cylinder hermetic rotary compressor described above, the plurality of blades 6a,
Of the blades 6b and 6c, the blade spring 7 is disposed on the lower blade 6c, while the other front and center blades 6a and 6b face the front head 31 and the middle plate 51, and the blades 6a and 6b. Reciprocally movable hooks 8 and 8 are provided, and the hooks 8 and 8 are attached to the blades 6a and 6b.
Hook locking portions 82, 8 that can be locked at the retracted positions of a and 6b
2 is formed so that the back side of the hooks 8 and 8 is communicated with the low pressure gas region in the cylinder 4c having the blade spring 7 through the communication passage 9.

That is, the blade spring 7 is provided on the blade 6c provided in the lower cylinder 4c,
The blade 6c is always urged to contact the roller 33, and the front head 31 and the middle plate 51 are opposed to the upper surfaces 61a and 61b of the blades 6a and 6b installed in the other cylinders 4a and 4b. , Fig. 3
The pin-shaped hooks 8 and 8 shown in FIG. 11 form sliding holes 81 and 81 that can reciprocate in the vertical direction, and the blades 6a and 6b are provided on the upper surfaces 61a and 61b. The hooks 8 and 8 provided in the sliding holes 81 and 81 at the positions retracted by the maximum amount due to the eccentric rotation of
The hook locking portion 82 for locking the hook by moving the
82 is formed. Incidentally, each of the blades 6a, 6
Both back sides of b and 6c are opened to the high pressure discharge space H in the casing 1. Further, the hook 8 may have a flat bottom surface as shown in FIG. 3, or may have an inclined surface at its tip as shown in FIG. Also,
Hook engaging portions 82 formed on the blades 6a, 6b,
The hook 82 is formed to have a width larger than that of the hook 8 so that the hook 8 can be accommodated in the hook engaging portion 82.
As shown in FIG. 5, an inclined surface may be formed on the bottom to facilitate the detachment of the hook 8 from the hook engaging portion 82. Further, the hook engaging portion 82 may be formed in a concave shape as shown in FIG. 5, or may be formed as a groove having an inclined surface and extending in the width direction as shown in FIG.

The hooks 8, 8 and the hook engaging portion 8
The upper cylinder 4 shown in FIG.
Describing based on the blade 6a of a, the hook 8
When the blade 6a is located at the maximum forward position shown by the chain double-dashed line in FIG. 7, the tip of the hook 8 contacts the upper surface 61a of the blade 6a, and the blade 6a is shown by the solid line in FIG. When the hook 8 is located at the maximum retracted position shown, the hook 8 is provided so as to be able to be engaged with the hook engaging portion 82, and when the lower end portion of the hook 8 is formed into a flat surface, the movement of the blade 6a. (A), the width of the hook 8 (b), the length from the maximum retracted position of the back surface of the blade 6a to the rear end of the hook 8 (c), the maximum back surface of the blade 6a. Assuming that the length from the retracted position to the front end of the hook 8 is (d),
(D) When the blade 6a advances by the maximum amount, the lower end advancement side of the hook 8 contacts at the end of the upper surface 61a of the blade 6a so that the hook 8 does not fall out of the sliding hole 81. And set to
The length of (b) is subtracted from (d), that is, the length of (c) is set so that the hook 8 is locked to the hook locking portion 82 when the blade 6a is retracted by the maximum amount. To do.

On the other hand, the back side of each of the hooks 8 and 8,
That is, communication passages 9 and 9 respectively communicating with the suction passage 11 in the cylinder 4c having the blade spring 7 are continuously formed at the upper end portions of the slide holes 81 and 81, and the communication passages 9 are also formed. , 9 to the suction passage 11
An electromagnetic valve 10 is provided which opens and closes the communication between the hook and the back side of the hooks 8 to control the capacity. That is, the back side of the hooks 8, 8 can be brought to a low pressure state by opening the solenoid valve 10, so that the load operation can be performed during operation, and the hook 8 can be closed by closing the solenoid valve 10. Since the back side of 8 can be in a high pressure state,
The hooks 8, 8 are locked to the hook locking portions 82, 82 so that the capacity can be controlled.

Next, the operation of the compressor described above will be described. At startup, the closed casing 1
Since the inside is in a low pressure state, at the time of starting, there is no pressure difference between the tip side and the back side of the hooks 8, 8.
Therefore, the hooks 8 and 8 are in contact with the blades 6a and 6b by their own weight. On the other hand, when the drive shaft 2 starts to rotate due to the activation of the compressor, the blades 6a, 6b, 6c slide due to the eccentric rotation of the eccentric portions 2a, 2b, 2c of the drive shaft 2, and the blades 6a, 6b, 6c slide. The lower blade 6c having the spring 7 repeatedly slides in conjunction with the eccentric rotation of the eccentric portion 2c to compress the refrigerant gas in the lower cylinder 4c, while the upper and central blades 6a are provided. , 6b, in the retracted position, the hooks 8 and 8 fall into the hook locking portions 82 and 82 and are locked, and the blades 6a and 6b stand still in the retracted position. Therefore, the eccentric portion 2
Since a and 2b run idle and no compression action occurs,
The compression of the refrigerant gas is performed only by the lower cylinder 4c. By doing so, when the compressor is started, the compression operation is performed only in the lower cylinder 4c, and the capacity can be reduced to ⅓. The load on the can be reduced.

When the pressure in the casing 1 rises due to the operation of the compressor, the blades 6a, 6b
Of the hooks 8 and 8 communicating with the back side through a gap has a high pressure, while the back side of the hooks 8 and 8 communicate with the low pressure suction passage 11. Since the pressure is low, the pressure difference causes the hooks 8 and 8 to be pushed to the low pressure side to move upward, and to be disengaged from the hook engaging portions 82 and 82. By this disengagement, the hooks 8 and 8 at the upper side and the central portion Since the back surfaces of the blades 6a and 6b communicate with the high-pressure discharge space H in the casing 1, the blades 6a and 6b are exposed to the high pressure acting on the back surface thereof.
a and 6b slide toward the center in the axial direction, and thereafter reciprocate following the eccentric rotation of the roller 33, and the capacity 100
% Compression operation is performed.

Moreover, the solenoid valves 10, 10 are provided in the communication passage 9.
By providing one or both of these solenoid valves in a closed state, the back side of the hooks 8, 8 can be made to have a high pressure, so that there is no pressure difference between the back side and the tip side, The hooks 8 and 8 are moved by their own weight so that the sliding holes 81 and
It is possible to lower 81 and engage with the hook engaging portions 82, 82. Therefore, the hooks 8, 8
The sliding of the blades 6a and 6b can be stopped by locking the blades 6a and 6b.
By opening and closing 0, the capacity can be controlled to 33% or 66%.

Also in the second embodiment, as in the first embodiment, the discharge pipe may be provided with a pressure adjusting valve which operates at a predetermined pressure, and by doing so, the compressor is started. Even if only one cylinder is activated at a time, the sealed casing 1 is hermetically sealed, so that the pressure in the casing 1 can be increased faster, and the start-up can be accelerated in spite of the activation of one cylinder.

In the second embodiment, the communication passage 9 formed on the back side of the hook 8 is provided with the suction passage 11 in the cylinder 4c having the blade spring 7.
However, the communication passage 9 may be communicated with an accumulator (not shown) that communicates with each suction passage 11 of the compression element 3.

[0039]

As described above, the multi-cylinder hermetic rotary compressor according to the present invention, in the first invention according to claim 1,
A discharge pipe 15 for discharging the compressed gas in the casing 1 to the outside is connected to the casing 1, and each cylinder 4
One of the plurality of blades 6a, 6b, 6c that comes into contact with the plurality of rollers 33, ... Installed in a, 4b, 4c and slides as the rollers 33 ,. A blade spring 7 is provided and the blades 6a, 6 are
Since the back side of b, 6c is opened inside the casing 1, the inside of the closed casing 1 is in a low pressure state at the time of starting, so that the blades 6a, 6b, 6
The pressure on the back side of c is low, and at the time of startup, the eccentric rotation of the eccentric portions 2a, 2b, 2c of the drive shaft 2 causes the blades 6a, 6b, 6c to start sliding and the blade spring 7 to move. Only the blade 6b that it has receives the bias of the blade spring 7 and repeats sliding in conjunction with the eccentric rotation of the eccentric portion 2b, and the refrigerant gas can be compressed only in the cylinder 4b that has this plate 6b. On the other hand, since the blade spring 7 is not disposed on the back side of each of the other blades 6a and 6c, the blade 7 is not biased by the spring 7 and is on the back side of the blades 6a and 6c. Since the pressure is low, the rollers 33, 33 once slide to the retracted position with the eccentric rotation, and stop at the retracted position. Therefore, the eccentric parts 2a and 2c run idle and no compression action occurs, and the compression of the refrigerant gas is performed only by the cylinder 4b having the blade spring 7. By doing so, when the compressor is started,
Since the compression operation can be performed only in the cylinder 4b having the blade spring 7, the load on the drive shaft 2 at the time of starting can be reduced, and the starting torque of the drive shaft 2 can be reduced accordingly.

When the pressure in the casing 1 rises due to the operation of the compressor, the blades 6a, 6c are pushed by the back pressure toward the rollers 33, 33 and slide toward the center of the shaft, and It is possible to perform reciprocating motion following the eccentric rotation of 33, and to perform compression operation of 100% capacity. Furthermore, in spite of the multi-cylinder, one of the blades 6a, 6b, 6c is used. Since only the blade spring 7 needs to be provided in the above, the number of parts can be reduced and the number of assembling steps can be reduced. Further, regarding the blades 6a and 6c in which the blade spring 7 is eliminated, the tip end of the blade and the roller 33 can be reduced. The friction with and can be reduced, and the efficiency can be improved accordingly.

Further, as described in claim 2, the discharge pipe 15 connected to the closed casing 1 is opened when the pressure in the casing 1 rises to a predetermined pressure,
By providing the pressure regulating valve P that allows the discharge pipe 15 to flow, the discharge pipe 15 can be closed at the time of starting the compressor to make the inside of the casing 1 in a sealed state, and the compressor is started. Even if only one cylinder is activated at a time, the sealed casing 1 is hermetically sealed, so that the pressure in the casing 1 can be increased faster, and the start-up can be accelerated in spite of the activation of one cylinder.

Further, as described in claim 3, the blade spring 7 is provided with a plurality of cylinders 4a, 4b, 4
When the drive shaft 2 is disposed on the back side of the blade 6b of the cylinder 4b located in the central portion of the axial direction c, a torque is generated in the central cylinder 4b when the drive shaft 2 rotates, and a torque corresponding to this torque is generated. Since the reaction force can be evenly shared by the bearings of the front head 31 and the rear head 32, the reliability of the compressor can be improved.

Further, in the multi-cylinder hermetic rotary compressor according to the second aspect of the present invention, the drive shaft 2 and the compression element 3 are arranged in the vertical direction, and the cylinders 4a, 4b,
The blade spring 7 is attached to one of the plurality of blades 6a, 6b, 6c which comes into contact with the plurality of rollers 33, ...
On the other hand, while the other blades 6a and 6b are opposed to the front head 31 or the middle plate 51,
Hooks 8 and 8 which can reciprocate with respect to the blades 6a and 6b are provided, and the hooks 8 and 8 can be hooked to the blades 6a and 6b at the retracted positions of the blades 6a and 6b. , 82 are formed to communicate the back side of the hooks 8, 8 with the region of low pressure gas in the cylinder 4c having the blade springs 7. Therefore, when the compressor is started, the blades 6c having the blade springs 7 are formed. Is repeatedly slid in conjunction with the eccentric rotation of the eccentric portion 2c to compress the refrigerant gas in the cylinder 4c having the blade 6c, while the other blades 6a, 6b are the closed casing 1 at startup. Since the inside is in a low pressure state, each of the hooks 8,
There is no pressure difference between the tip side and the back side of 8, and the hooks 8,
When the blades 6a and 6b are retracted, 8 is dropped and locked by the hook locking portions 82 and 82 by its own weight, and is reliably stopped at the retracted position, so that the eccentric portions 2a and 2b idle. As a result, the refrigerant gas is not compressed, and the compression operation is performed only in the cylinder 4c having the blade spring 7 to reduce the load on the drive shaft at startup.

When the pressure in the casing 1 rises due to the operation of the compressor, the back side of the blades 6a and 6b having the hooks 8 and 8 also rises, and the hook 8 communicating with the back side. While the tip side of 8 is high pressure,
Since the back side of the hooks 8, 8 communicates with the low-pressure suction passage 11 and has a low pressure, the pressure difference causes the hooks 8, 8 to be pushed toward the low-pressure side to move, thereby locking the hooks. The blades 6a and 6b are separated from the portions 82 and 82, and the blades 6a and 6b slide toward the center in the axial direction due to the high pressure acting on the back surface side, so that the compression operation of 100% capacity can be performed.

Further, in the second aspect of the invention, as described in claim 5, the electromagnetic communication is provided in the communication passage 9 which communicates the low pressure gas region in the cylinder 4c having the blade spring 7 and the back side of each of the hooks 8 and 8. By providing the valve 10, by operating one or both of the solenoid valves 10 in the closed state, the back side of the hooks 8, 8 can be made to have a high pressure, so that the pressure between the back side and the tip side. There is no difference, and the hooks 8 are self-weighted so that the sliding holes 8
1, 81 are lowered to be locked by the hook locking portions 82, 82, and the sliding of the blades 6a, 6b can be stopped by this locking. Therefore, the capacity control can be performed by opening / closing the solenoid valve 10. It can be done.

[0046]

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing a first embodiment of a multi-cylinder hermetic rotary compressor of the present invention.

FIG. 2 is a partially cutaway sectional view showing a second embodiment of the multi-cylinder hermetic rotary compressor of the present invention.

FIG. 3 is an example of a hook used in the multi-cylinder hermetic rotary compressor of the second example.

FIG. 4 is another embodiment of the hook used in the multi-cylinder hermetic rotary compressor of the second embodiment.

FIG. 5 is an embodiment of a blade used in the multi-cylinder hermetic rotary compressor of the second embodiment.

FIG. 6 is another embodiment of the blade used in the multi-cylinder hermetic rotary compressor of the second embodiment.

FIG. 7 is an operation explanatory view of blades of the multi-cylinder hermetic rotary compressor of the second embodiment.

FIG. 8 is an explanatory view showing a conventional multi-cylinder hermetic rotary compressor.

FIG. 9 is an explanatory view showing another conventional multi-cylinder hermetic rotary compressor.

[Explanation of symbols]

 1 Closed casing 15 Discharge pipe 2 Drive shafts 2a, 2b, 2c Eccentric part 3 Compression elements 4a, 4b, 4c Cylinder 51, 52 Middle plate 31 Front head 32 Rear head 33 Roller 6a, 6b, 6c Blade 7 Blade spring P Pressure regulating valve 8 Hook 82 Hook locking part 9 Communication passage 10 Solenoid valve

Claims (5)

[Claims] 1. A drive shaft 2 having a plurality of eccentric portions 2a, 2b, 2c in an axial direction in a closed casing 1, and a plurality of cylinders 4 in which the eccentric portions 2a, 2b, 2c are located.
a, 4b, 4c and middle plates 51, 52 interposed between the cylinders 4a, 4b, 4c, and the cylinders 4
A multi-cylinder hermetic rotary compressor in which a compression element 3 including a front head 31 and a rear head 32 for sandwiching a, 4b, 4c is internally housed, and the compressed gas in the casing 1 is discharged to the outside of the hermetic casing 1. A plurality of blades connected to the discharge pipe 15 and contacting a plurality of rollers 33 ... Installed in each of the cylinders 4a, 4b, 4c, and sliding as the rollers 33 ... 6a, 6b, 6c
A multi-cylinder rotary compressor, characterized in that a blade spring 7 is arranged in one of the blade springs, and the back side of each of the blades 6a, 6b, 6c is opened in the casing 1. 2. A discharge pipe 15 connected to the closed casing 1.
The multi-cylinder hermetic rotary compressor according to claim 1, further comprising a pressure adjusting valve P that opens when the pressure in the casing 1 reaches a predetermined pressure and allows the discharge pipe 15 to flow. .. 3. The multi-cylinder hermetic seal according to claim 1, wherein the blade spring 7 is arranged on the back side of the blade 6b of the cylinder 4b located in the axial center of the plurality of cylinders 4a, 4b, 4c. Type rotary compressor. 4. A drive shaft 2 having a plurality of eccentric portions 2a, 2b, 2c in the axial direction in a closed casing 1, and a plurality of cylinders 4 in which the eccentric portions 2a, 2b, 2c are located.
a, 4b, 4c and middle plates 51, 52 interposed between the cylinders 4a, 4b, 4c, and the cylinders 4
A multi-cylinder hermetic rotary compressor having a compression element 3 having a front head 31 and a rear head 32 for sandwiching a, 4b, 4c, the drive shaft 2 and the compression element 3
Are arranged in the vertical direction and come into contact with a plurality of rollers 33 ... Installed in the cylinders 4a, 4b, 4c, and the rollers 33 ...
..A plurality of blades 6a, 6 sliding with the rotational drive of
The blade spring 7 is disposed on one of the blades 6b and 6c, and reciprocally movable with respect to the blades 6a and 6b on the front head 31 or the middle plate 51 on which the other blades 6a and 6b face each other. Hook 8, 8
And hooks 8 and 8 are formed on the blades 6a and 6b so that the hooks 8 and 8 can be locked at the retracted positions of the blades 6a and 6b.
The multi-cylinder hermetic rotary compressor is characterized in that the back side thereof is communicated with the low-pressure gas region in the cylinder 4c having the blade spring 7. 5. A cylinder 4 having a blade spring 7.
The multi-cylinder hermetic rotary compressor according to claim 4, wherein an electromagnetic valve 10 is provided in a communication passage 9 that communicates the low-pressure gas region in c with the back side of each of the hooks 8, 8.