JPS6030477Y2 - variable displacement compressor - Google Patents

Description

[Detailed description of the invention] The present invention relates to a variable displacement compressor for use in refrigeration equipment, specifically, a compression element formed from a cylinder having a front head and a rotor, between the suction side and the discharge side of the cylinder chamber. The present invention relates to a variable displacement compressor which is provided with an intermediate discharge hole and which is opened and closed by an intermediate discharge valve to control the capacity of the compressor in response to fluctuations in negative load.

In general, a modified compressor is provided with an intermediate discharge hole that opens into the cylinder chamber in the side wall of the cylinder, a valve chamber is formed on the back side of the discharge hole with respect to the cylinder chamber, and an intermediate discharge valve is attached to this valve chamber. At the same time, the valve chamber is communicated with the suction side of the compressor or the low-pressure part and the high-pressure part of the refrigeration system through communication introduction pipes, and a flow control means such as an on-off valve is interposed in these communication introduction pipes, When the load is high, high-pressure refrigerant is guided from the high-pressure section to the valve chamber and the intermediate discharge valve is closed, thereby performing high-capacity operation in which the entire amount of suction gas of the compressor is discharged from the discharge port. Sometimes, the valve chamber is communicated with the low-pressure section, the valve chamber is brought to a low pressure, and the intermediate discharge valve is opened to guide refrigerant in the middle of the compression stroke from the intermediate discharge hole to the low-pressure section, and the compressor The amount of gas discharged from the engine is reduced to enable effective low-capacity operation.

However, according to the compressor configured as above, the first
In order to form the valve chamber of the intermediate discharge valve, it is necessary to provide a valve cover on the cylinder side wall via a seal member, and also to provide the introduction pipe to the valve cover via a seal member, and to form the valve chamber of the intermediate discharge valve. It is necessary to separately provide a bypass pipe from the intake side to the suction side, and there is a problem that the number of parts is large and it takes a long time to assemble. However, there was a problem in that the external dimensions of the entire compressor became large.

Further, it is difficult to always reliably seal the high pressure or low control pressure introduced into the valve chamber from the introduction pipe by the sealing member, and there is a problem in that the refrigerant may leak from these sealing members.

The present invention was devised in view of the above-mentioned problems, and the purpose is to reduce the number of parts and simplify assembly without requiring valve covers, bypass pipes, seal members, etc. as in the past. It is an object of the present invention to provide a compressor that is capable of reducing the overall external dimensions and always has reliable sealing performance.

A compressor in which a compression element including a cylinder having a rotor is interposed between a front head and a catcher head is fixed by press-fitting the front head into a housing, and the bottom of the housing is an oil reservoir, The rear head is blindly provided with a valve hole that opens between the suction side and the discharge side of the cylinder chamber, and a finger-type intermediate discharge valve is installed in the valve hole so as to be movable in the vertical direction. A valve seat body having a through hole of a required size and a seat surface is fixed to the opening of the hole to the cylinder chamber, while a control introduction pipe is connected to the front head press-fitting point in the housing, and the control A control pressure introduction passage is formed through the front head, the cylinder, and the rear head to connect the pressure introduction pipe and communicate the control pressure introduction pipe with a rear chamber of the intermediate discharge valve in the valve hole, and , the rear head is characterized in that a bypass passage is formed in the rear head to communicate the valve hole with the suction side of the compressor.

Note that the rotor type in the present invention includes a sliding vane type and a rolling piston type, and the type is not particularly limited.

Further, although the compressor of the present invention is mainly used in a refrigeration system, its capacity control may be performed according to load fluctuations during cooling or heating, or may be performed in response to cooling load and heating load.

In addition, the fluctuation in the load includes an increase or decrease in the number of operating indoor units when the refrigeration system is a so-called multi-type refrigeration system in which multiple indoor units are connected to one outdoor unit, as well as changes in the number of operating indoor units. Regardless of the type, size, or purpose of the refrigeration equipment, such as when it is combined with an indoor unit or one-to-one, load fluctuations between mid-season and summer or winter, or between daytime and nighttime, etc. This includes fluctuations in the load.

Embodiments of the compressor of the present invention will be described below based on the drawings.

What is shown in the drawing is a high-pressure mood type rotary compressor, in which a motor element A is disposed above and below inside a cylindrical housing 1, and a compression element B is disposed below. Specifically, the stator 8 of the motor element A and the front head 11 of the compression element B are press-fitted and supported, a bottom plate 2 is attached to the bottom of the housing 1, a cover plate 3 is attached to the top, and the housing A suction pipe 4 and a control pressure introduction pipe 5 (to be described later) are mounted on the side wall of 1, and a discharge pipe 6 and an electric wire attachment 7 to the stator 8 are mounted on the cover plate 3.
It is configured by attaching each of them.

Further, the bottom of the housing 1 is made into an oil reservoir like the conventional one.

Further, the motor element A includes the stator 8 and the motor rotor 9.
and a motor shaft 10 fixed to the rotor 9; It consists of a cylinder 14 with a rotor 13 sandwiched between heads 11, 12 and fixed to the motor shaft 10.

The compression element B has each opposing clamping surface polished to serve as a metal seal face, and these clamping surfaces are tightly pressed by a connecting member 15 such as a screw. In this way, the compression element B, which has been made into one body, is press-fitted into the inside of the housing 1 together with the motor element A.

The front head 11 includes a suction passage 11a that communicates with the suction pipe 4, and a suction port 11b that opens into the cylinder chamber 14a of the cylinder 14 and includes a suction valve 11d.
and a discharge passage 11c opening into the housing 1, the cylinder 14 has a suction port 14b communicating with the suction port 11b, and a discharge valve 14e communicating with the cylinder chamber 14a via a communication passage 14d.・・・・・・
A discharge port 14c having a diameter and a communication passage 14f communicating with the discharge passage 11c are provided on the suction side and the discharge side of the cylinder chamber 14a, respectively.

Further, the rotor 13 installed in the cylinder chamber 14a has two
The vanes 15, 15 are slidably supported, and their center portions are passed through the motor shaft 10 and fixed to the motor shaft 10. It rotates to compress the refrigerant sucked in from the suction port 11b and discharge it to the discharge port 14c.

The rotor 13 may be of the sliding vane type as described above or may be of the rolling piston type.

The rear head 12 also includes a communication groove 12a that communicates the suction port 14b and the cylinder chamber 14a, a lubricating oil supply path 12b that opens to the communication groove 12a, and a discharge port 14c that communicates with the communication path 14f. Communication groove 12
c.

Therefore, the feature of the present invention is that a blind valve hole 12d and a bypass passage 12e are formed in the rear head 12, and an intermediate discharge valve 16 is installed inside the valve hole 12d so as to be freely movable in the vertical direction. A through hole 17a of a predetermined size and a seat surface 17b are provided at the opening of the cylinder chamber 12d to the cylinder chamber 14a.
The valve seat body 17 with the valve seat body 17 is fixed, and the control pressure introduction pipe 5 is connected from the back chamber 18 of the intermediate discharge valve 16 in the valve hole 12d.
A control introduction passage 19 is provided to communicate with the control introduction passage 19.

The rear head 12 is made of a third metal by a lost wax casting method.
As shown in the figure, the valve hole 12d is opened at an intermediate position between the suction side and the discharge side of the cylinder chamber 14a, and the opening end of the valve hole 12d is opened so that the lower part becomes blind. A press-fit hole 12f for the valve seat body 17 is formed in the valve hole 12d, and a bypass passage 12e is provided in the middle of the valve hole 12d for communicating with the communication 112a and communicating with the suction side of the cylinder chamber 14a and the suction port 14b. Provided with a valve hole 12
The control pressure introduction passage 1 is L-shaped from the lower end of d, opens at the upper surface of the rear head 12, and communicates with the control pressure introduction pipe 5.
This is done to form 9.

The rear head 12 formed in this manner has the valve hole 1
The intermediate discharge valve 16 is installed inside the 2d sum, and the press-fit hole 12
After the valve seat body 17 is press-fitted into the valve seat f, the upper surface of the head 12 facing the cylinder 14 and the upper surface of the valve seat body 17 are simultaneously polished and finished flush to form the face surface for the metal seal described above. .

The intermediate discharge valve 16 installed in the valve hole 12d of the rear head 12 is mainly made of synthetic resin such as Polyflon, and extends into the through hole 17a of the valve seat body 17. a head 16a that closes the valve, a valve portion 16b that contacts the seat surface 17b of the valve seat body 17, and a cylindrical main body 1 having a smaller diameter than the inner diameter of the valve hole 12d.
6c and an annular protrusion 16d that contacts the inner circumferential surface of the valve hole 12d at the rear end of the main body 16c, and between the protrusion 16d and a step provided in the middle of the valve hole 12d. A spring 20 is interposed to constantly bias the discharge valve 16 so that the through hole 17a of the valve seat body 17 is opened.

21 is a coil spring, and an annular recess 1 is provided in the protrusion 16d.
6e is provided and placed inside the recess 16e, and the diameter of the protrusion 16d is expanded outward to seal the gap between the protrusion 16d and the valve stem 12e.

The control pressure introduction pipe 5 is supported so as to protrude into the front head 11 where it is press-fitted into the housing 1, and the distal end of the passage 19 is connected to the distal opening of the introduction pipe 5, and the passage 19 is connected to the front head 11. The control pressure is communicated with the rear chamber 18 through the cylinder 14 and an L-shaped passage 19 provided in the rear head 12, and the control pressure is introduced into the back pressure chamber 18 from the introduction pipe 5 through the communication passage 19. It is.

This control pressure is set to a pressure value lower than the pressing force of the spring 20 when the compressor load is low and the compressor is operated at a low capacity. By opening the through hole 17a, the refrigerant in the middle of the pressure stroke is forced to bypass from the through hole 17a to the suction side of the cylinder chamber 14a via the bypass passage 12c. When performing capacity operation, a pressure value higher than the pressing force of the spring 20 is applied, and this pressure causes the intermediate discharge valve 16 to resist the spring 20 and close the through hole 17a.

Since the intermediate discharge valve 16, the bypass passage 12e, and other structural parts for variable capacity are provided in the rear head 12, there is no need to provide a special space for the structural parts.
The space existing below the compression element B can be used effectively, and the height of the nosing 1 in the vertical direction can be made sufficiently low.

Moreover, the valve hole 12d provided in the rear head 12 is blind on the lower side, and after the intermediate discharge valve 16 is inserted into the valve hole 12d, the valve seat body 17 is press-fitted into the opening to support it. Since the control pressure introduction passage 19 communicating with the control pressure introduction pipe 5 is communicated with the rear chamber 18 through the space between the rear heads 12, the rear chamber of the intermediate discharge valve 16 is formed as in the conventional case. In addition to not requiring a valve cover and sealing member for the
There is no need for a special seal structure for communication between the two or bypass pipes, the number of parts can be reduced and assembly is easy, and there are no connecting parts so there is no need to worry about sealing. It is possible to provide reliable sealing performance.

The valve seat body 17 and its through hole 17a are formed in a size that corresponds to the capacity value W of low capacity operation to be described later, which is performed when the compressor load is low, and the size of the through hole 17a is changed. By preparing a wide variety of valve seat bodies 17, the present invention can be easily applied to models having different capacitance values W.

That is, by attaching to the rear head 12 a through hole 17a shaped to a size suitable for different capacitance values, the rear head 12 can be used as a common component.

As described above, the valve seat body 17 allows various valve seat bodies 17 having different sizes of through holes 17a to be attached to a common rear head 12. As shown in Figures 1 and 2, the valve seat body 17 has a cylindrical shape, its outer diameter is the same regardless of the size of the through hole 17a, and the rear head 12 has a constant diameter corresponding to the outer diameter of the valve seat body 17. A press-fitting hole 12f of the same size is provided, and each of the various valve seat bodies 17 can be press-fitted into the press-fitting hole 12f so that it can be held in hand.

When the compressor load is low and low capacity operation is performed,
For a compressor that requires low capacity operation at a desired low capacity value W, a compressor incorporating a valve seat body 17 whose through hole 17b has a size commensurate with the low capacity value W is used. Then, when the low control pressure is introduced into the back chamber 1B, the intermediate discharge valve 16 opens the through hole 17a, and out of the refrigerant amount Q1 that has reached the through hole 17a from the suction side of the cylinder chamber 14a, the low volume Only a predetermined amount Q2 of refrigerant corresponding to the value W is directly sent to the discharge side and compressed, and the remaining predetermined amount Q1-Q2 of refrigerant returns to the suction side from the through hole 17a via the bypass passage 12c and is discharged. By using the predetermined amount 92 of refrigerant, the desired low capacity operation can be performed.

Therefore, it is possible to manufacture a wide variety of models with different capacity values W during low capacity operation when the compressor load is low by using common parts except for the valve seat body 17, and the number of parts can be reduced. There are few parts, easy to manage, and easy to manufacture.

The compressor of the present invention, constructed as described above, can be applied to a refrigeration system as shown in FIGS. 4 and 5, and the amount of refrigerant circulated can be controlled in accordance with the load.

4 and 5, 31 is a four-way switching valve, 32 is an outdoor coil that becomes a condenser during cooling and an evaporator during heating, and 3
3 is a liquid receiver, 34 is an expansion mechanism, 35 is an indoor coil that becomes an evaporator during cooling and becomes an evaporator during heating, and 36 is an accumulator, in which refrigerant is discharged from the compressor by switching the four-way switching valve 31. Cooling can be achieved by circulating the air as shown by solid arrows, and heating can be achieved by circulating it as shown by dotted arrows.

In the system shown in FIG. 4, the opening and closing of the intermediate discharge valve 16 is controlled according to the load fluctuations in the above-mentioned air-conditioning operation. It is connected via a switching valve 37,
In addition, the one shown in FIG. 5 is such that the opening and closing of the intermediate discharge valve 16 is controlled by switching between the cooling operation and the heating operation, so that the control introduction pipe 5 has a high pressure during heating and a low pressure during cooling. It is connected to the low pressure gas pipe 38.

4, when the load is above a predetermined value, the three-way switching valve 37 is switched as shown by the solid line in FIG. Since it is introduced into the rear chamber 18 through the pressure introduction passage 19, the intermediate discharge valve 16 moves against the spring 20, closing the through hole 17a as described above.

By closing this through hole 17a, the suction pipe 4 and the suction passage 11
The low-pressure gas refrigerant introduced into the suction side of the cylinder chamber 14a through the a1 suction port 14b1 communication groove 12a is compressed by the rotation of the rotor 13, and is then transferred to the discharge port 14c.
, communication groove 12c, communication path 14f from discharge passage 11c
The entire amount is discharged from the discharge pipe 6 through the inside of the housing 1, and heating and cooling can be performed by high-capacity operation.

Further, when the load decreases below a predetermined value, the three-way switching valve 37 is switched as shown by the dotted line in Figure 4, and by this switching, the back chamber 18 is connected to the suction pipe 4.
As a result, the intermediate discharge valve 16 is opened by the action of the spring 20, and the through hole 17a is opened.

Due to this opening, it is introduced into the suction side of the cylinder chamber 14a,
Due to the rotation of the rotor 13, a predetermined amount Q□-Q2 of the refrigerant amount q during the compression stroke is transferred to the through hole 17a.
The refrigerant returns to the suction side via the bypass passage 12e, and only the remaining predetermined amount Q2 of the refrigerant is compressed in the process from the through hole 17a to the discharge side, and is discharged through the above-mentioned path. The low capacity operation is controlled at a capacity value W that corresponds to the capacity value W.

Therefore, when the load is low, the amount of refrigerant circulation can be reduced.
This allows the compressor power to be reduced.

Furthermore, since the amount of refrigerant circulation can be controlled in accordance with the load, it is possible to prevent liquid from returning to the compressor, which occurs when the cooling load decreases, and from abnormally increasing high pressure, which occurs when the heating load decreases.

In addition, in FIG. 5, when heating operation is performed by switching the four-way primary switching valve 31, high pressure gas flows into the control pressure introduction pipe 5, and the intermediate discharge valve 1
6 is closed to enable high-capacity operation. Also, in the case of cooling operation, low pressure gas flows into the control pressure introduction pipe 5, and the intermediate discharge valve 16 is closed as in the case of low load described above.
is opened, and low capacity operation can be performed at the capacity value W.

Although the refrigeration equipment shown in Figs. 4 and 5 is a heat pump type refrigeration equipment, it can be similarly applied to a refrigeration equipment exclusively for cooling, and two indoor coils 35 can be used to cool and heat two rooms. However, the present invention can also be applied to the case where only one indoor coil 35 is provided.

As described above, in the present invention, structures for variable capacity such as intermediate discharge valves, valve holes, control pressure introduction passages, and bypass passages are provided in the rear head, so it is necessary to provide a special space for the structures. Therefore, although the intermediate discharge valve is freely movable in the rear head, the height of the entire compressor is high. The height is comparable to that of a constant volume tray compressor.

Moreover, there is no need to separately connect and provide a valve hole with a blind bottom side and a bypass passage inside the rear head.
The control pressure introduction passage is formed in a body shape and connects the control pressure introduction pipe to a press-fitting part of the front head in the housing, and communicates the control pressure introduction pipe with the rear chamber. Since it is formed within the member of the compression element, there is no need for the conventionally used sealing member and valve cover for forming the valve chamber, the total number of parts can be reduced, and assembly can be performed easily.

Furthermore, even when manufacturing multiple models with different capacity values W during low-capacity operation, the rear head can be manufactured as a common part by simply preparing a variety of valve seat bodies with different through-hole sizes. , parts management is easy, and all of the various models mentioned above can be manufactured easily.

[Brief explanation of the drawing]

Figures 1 to 3 show an embodiment of the compressor of the present invention, with Figure 1 being a longitudinal sectional view, Figure 2 being a cross sectional view, and Figure 3 showing the main parts before assembly. The explanatory drawings, FIGS. 4 and 5 are refrigeration piping system diagrams of a refrigerant device to which the compressor of the present invention is applied. 11...Front head, 12...Rear head, 12d...Valve hole, 12c...
・Bypass passage, 13... Rotor, 14...
...Cylinder, 16...Intermediate discharge valve, 17.
...Valve seat body, 17a...Through hole, 18.
...Back chamber, 19...Control pressure introduction passage.

Claims (1)

[Scope of utility model registration request] In a compressor, a compression element comprising a cylinder having a rotor interposed between the front head and the catcher head is fixed by press-fitting the front head into a housing, and the bottom of the housing is an oil reservoir, The rear head is blindly provided with a valve hole that opens between the suction side and the discharge side of the cylinder chamber, and a finger-type intermediate discharge valve is installed in the valve hole so as to be movable in the vertical direction. A valve seat body having a through hole of a required size and a seat surface is fixed to the opening of the hole to the cylinder chamber, while a control pressure introduction pipe is connected to the front head press-fitting part in the housing, and A control pressure introduction passage that communicates a control pressure introduction pipe with a rear chamber of the intermediate discharge valve in the valve hole is formed to penetrate through the front head, the cylinder, and the rear head, and the valve hole is formed in the rear head. A variable capacity compressor, characterized in that a bypass passage is formed that communicates with the compression suction side.