JPS642797B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a rotary compressor whose compression capacity can be controlled in two stages. Sixth, the purpose of simplifying the mechanism by sharing the capacity control passage, which is an element, is to prevent chattering of the control valve provided in relation to both the passages.

(Prior art) In rotary compressors used in refrigeration equipment, etc.
Compressors that have capacity control ports and injection ports opened at predetermined positions facing the closed space during the compression process in the cylinder chamber, and whose compression capacity can be controlled in two stages, have recently come into widespread use. .

Refrigeration equipment is a device that undergoes severe load fluctuations, so
When the load is large, intermediate-pressure gas refrigerant is sent into the cylinder chamber from the injection port to increase the compressor output by increasing the density of the compressed gas, while when the load is small, the capacity control port is injected into the cylinder chamber. By forming a circuit that communicates the space in the cylinder chamber during the compression process with the suction side for a certain period of time, the compression start time is delayed and the compressor output is reduced. The capacity control mechanism can be roughly divided into a common port type in which both ports are common, an individual passage type in which the injection gas passage and a capacity control passage are each independent systems, and a common type in which both passages are shared. There are three types of passageways.

(Problems to be Solved by the Invention) The first common port system uses a compressor having the structure shown in FIGS. 1 and 2 as an element, in which the piston valve 16' of the control valve 14' By supplying gas, the common port 20 is operated to close it, and intermediate pressure gas is injected from the common port 20 through the hole 21 penetrating the piston valve 16' to increase the output. By cutting off the supply of pressure gas and moving the piston valve 16' away from the common port 20 by elastic force, the bypass passage 12' and the common port 20 are communicated with each other to reduce the output. There is.

In this common port method, since one port is shared, it is impossible to set the hole diameter and position to optimize both the increase and decrease of capacity, and the control performance of one of them will be sacrificed. There were flaws.

The second individual passage system uses a compressor with the structure shown in Figure 3 as an element, and since each passage is an independent passage type, it can be designed to exhibit control performance suitable for increasing and decreasing output. However, a piping system 22 for opening and closing the control valve 14' interposed between the bypass passage 12' and the capacity control port 9', and a piping system 23 and 2 for sending intermediate pressure gas to the injection port 10'. This requires system piping, which has the disadvantage of increasing the number of parts and increasing manufacturing costs.

The third common passage system, as shown in Figs. 4 and 5, has an injection port 10' connected to the passage 24 to which intermediate pressure is applied when the output increases and suction pressure is applied when the output decreases, and a valve. The compressor has a structure in which a capacity control port 9' is connected to a chamber 26 connected to the passage 24 through a passage 25, and the structure is simplified in that it has a common passage. However, when operating under reduced capacity, every time the cylinder chamber communicating with the injection port 10' is switched from suction to compression, compressed gas flows back into the injection port 10'. The disadvantage is that the valve 25 which is open is pushed, causing the valve 25 to chatter and generate vibration noise, which is inconvenient and leads to noise.

Further, when the operation is performed under increased output in which intermediate pressure gas is injected from the injection port 10', the capacity control port 9' remains open, so that refrigerant gas flows into the chamber 26 and the space 27 of the valve seat. There is also the problem that when the air flows in, the space becomes a dead space, which reduces compression capacity and efficiency.

In this way, in order to deal with the fact that each type of conventional rotary compressor has its advantages and disadvantages,
The present invention has been made to provide a rotary compressor capable of eliminating the above-mentioned defects, and in particular, a capacity control port, an injection port, and a control port for supplying intermediate pressure gas for control to the compressor. By adopting a configuration in which a control valve is provided in connection with the passage and the bypass passage that communicates with the suction passage, the capacity control port can be opened and closed reliably, and the device can be simplified and compression capacity maintained efficiently. It is intended to

(Means for Solving the Problems) As is clear from the embodiments of the attached drawings, the present invention provides a capacity control port 9 facing the closed space where the pressure increases during the compression process of the cylinder chamber 1a.
In a rotary compressor, an injection gas passage 11 communicating with the injection port 10 and a bypass passage 12 communicating with the suction passage 5 have a pressure lower than the discharge pressure and higher than the suction pressure. A piston valve 16 is slidably housed in a cylindrical chamber 15 having one end communicating with a control passage 13 through which intermediate pressure gas is supplied when increasing the capacity of the compressor and the capacity control port 9. , a control valve in which elastic force is applied to the piston valve 16 in a direction away from the capacity control port 9, and the capacity is increased by separating the piston valve 16 from the capacity control port 9 due to the elastic force. A control valve 14 is provided which opens the control port 9 and closes the capacity control port 9 by contacting the capacity control port 9 against elastic force, while the bypass passage 12 is connected to a piston valve 16
When separated from the capacity control port 9, it is connected to the front chamber part, which is a space formed on the side of the capacity control port 9 in the cylinder chamber 15, and communicated with the capacity control port 9 at the time of separation, The control passage 13 is connected to the piston valve 1 in the cylinder chamber 15 at the time of separation.
6 is connected to a constant rear chamber which is a space existing on the rear chamber side which is opposite to the capacity control port 9, and furthermore, the injection gas passage 11 is connected to the constant pressure gas to the rear chamber. When the piston valve 16 is slid against the elastic force to the capacity control port 9 and brought into contact with the capacity control port 9, the piston valve 16 is continuously formed on the rear chamber side and always continuous with the rear chamber part. It is characterized in that it is connected to the rear chamber section where the passages 11 and 13 are brought into communication with each other when they come into contact with each other.

(Function) When controlling the capacity of the compressor to reduce the capacity, for example, by closing the valve provided in the control passage 13 so as not to send intermediate pressure refrigerant gas into the control passage 13, the cylinder The pressure in the rear chamber inside the chamber 15 decreases, and the elastic force causes the piston valve 16 to move away from the displacement control port 9, thereby closing the displacement control port 9.
is opened, and the bypass passage 12 and the volume control port are communicated via the front chamber.

Therefore, until the roller 4 passes through the capacity control port 9, the sealed space within the cylinder chamber 1a is communicated with the suction side, and a portion of the compressed refrigerant gas is returned to the suction side, resulting in a reduction in output. It is.

On the other hand, when controlling the capacity to increase the capacity, if intermediate pressure refrigerant gas is supplied to the control passage 13,
As a result, the rear chamber part of the cylinder chamber 15 is always in the intermediate pressure region.
The piston valve 16 is reliably brought into contact with the capacity control port 9 against the elastic force, and the capacity control port 9 is closed, and the injection gas passage 11 and the control passage 13 are always connected to the rear chamber. The intermediate pressure gas passes through the injection gas passage 11, is ejected from the injection port 10, and is sent to the cylinder chamber 1a in the compression process, resulting in an increase in output. .

In this way, capacity control is possible simply by intermittent supply of intermediate pressure refrigerant gas to the control passage 13.

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

In Fig. 6, a cylinder 1 has a cylinder chamber 1a having a circular horizontal cross section in the center, and the cylinder is press-fitted into a cylindrical casing 2 and fixed by welding at key points. .

A circular roller 4 eccentrically attached to the rotating shaft 3 is housed in the cylinder chamber 1a, and is provided so as to be able to rotate while slidingly contacting the peripheral wall of the cylinder chamber 1a.

The cylinder 1 is provided with a suction passage 5 that opens into the cylinder chamber 1a and a blade chamber 6, and a blade 7 that is slidably fitted into the blade chamber 6 is attached to the circumferential surface of the roller 4. It faces into the cylinder chamber 1a so as to be able to touch it, and although not shown, a bullet is interposed on the back side of the blade 7, and
By introducing discharge pressure into the blade chamber 6, a high-pressure region similar to the atmosphere inside the casing 1 is created, so that the tip of the blade 7 is kept in elastic contact with the roller 4. The blade 7 divides the cylinder chamber 1a into two chambers: a low pressure chamber communicating with the suction passage 5 and a high pressure chamber communicating with a discharge passage provided in a front head (not shown).

The configuration described above is a well-known structure related to a general rolling piston type rotary compressor, but the rear head 8 attached to the lower surface of the cylinder 1 has a capacity control port as shown in an enlarged view in FIG. 9 and
An injection port 10, an injection gas passage 11, a bypass passage 12 communicating with the suction passage 5, a control passage 13, and a control valve 14 are provided, respectively;
The cylinder 1 is hermetically penetrated through the casing 2.
A passage 18 that opens to the outside and communicates with the control passage 13 is provided.

The capacity control port 9 and the injection port 10 are arranged such that the capacity control port 9 is located on the upper side close to the suction passage 5 with respect to the direction of revolution of the roller 4, and the capacity control port 9 is located on the upper side close to the suction passage 5. Then, openings are made at predetermined positions on the surface forming the wall of the cylinder chamber 1a. Note that the front-to-back relationship between the ports 9 and 10 is not necessarily limited to the above-mentioned arrangement, and the front and back may be reversed depending on design conditions.

The injection gas passage 11 is connected to the injection port 10 and the control valve 1.
4 and is a passageway for communicating with rear head 8.
However, this is formed into a considerably narrower passage than the bypass passage 12.

The bypass passage 12 is a hollow passage formed in an arc shape in the rear head 8, and is a hollow passage formed in the cylinder chamber 1.
The end opening facing a is connected to the suction passage 5 at a position close to it, and the other end is connected to the control valve 1.
Connected to 4.

The control passage 13 is a passage for communicating the passage 18 and the control valve 14, and is formed within the rear head 8.

Next, the control valve 14 has a piston valve 16 slidably housed in a cylindrical chamber 15 whose one end communicates with the capacity control port 9, and a coil spring 17.
This applies elastic force to the piston valve 16 in the direction away from the capacity control port 9, and the elastic force of the piston valve 16 causes the capacity control port 9 to
opening the capacity control port 9 by separating it from the
The capacity control port 9 is closed by contacting the capacity control port against the elastic force.

Further, the bypass passage 12 is connected to the piston valve 1.
6 is separated from the capacity control port 9,
The control passage 13 is connected to the front chamber, which is a space formed on the side of the capacity control port 9 in the cylinder chamber 15, to communicate with the capacity control port 9 at the time of separation, and the control passage 13 is connected to the front chamber, which is a space formed on the side of the capacity control port 9 in the cylinder chamber 15. Always connected to the rear chamber part, which is a space existing on the rear chamber side opposite to the capacity control port 9 with respect to the piston valve 16 inside,
Further, the injection gas passage 11 is connected to the displacement control port 9 by constantly supplying intermediate pressure gas to the rear chamber and sliding the piston valve 16 against the elastic force to the displacement control port 9. When brought into contact, the passages 11 and 13 are connected to the rear chamber section which is always formed continuously with the rear chamber section on the rear chamber side, and the two passages 11 and 13 are communicated with each other at the time of this contact.

Further, the injection gas passage 11 is connected to open to the side wall of the intermediate portion of the cylinder chamber 15, and the passage 11 is switched to communicate with the front chamber or the rear chamber of the cylinder chamber 15 depending on the position of the piston valve 16. That's what I do.

That is, by setting the connection position of the injection gas passage 11 to a predetermined position, the piston valve 1
When the vehicle moves backward, the passage 11 communicates with the front chamber, and when the vehicle moves forward, the passage 11 communicates with the rear chamber, and it is important that such switching communication is performed.

The mode of capacity control operation of the compressor configured as described above will be explained next. When the load of the refrigeration system using the compressor as the drive source is light and the capacity control operation is performed, the casing 2 is inserted into the passage 18. The valve 19 connected outside is closed to prevent intermediate pressure gas refrigerant from being fed into the control passage 13.

As a result, the pressure in the rear chamber inside the cylinder chamber 15 is constantly reduced, and the piston valve 16 is pushed up in the direction away from the capacity control port 9 by the elastic force, and as a result, the seventh valve As shown in the figure, the capacity control port 9, the injection port 10, and the bypass passage 12 communicate with each other through the front chamber of the cylinder chamber 15.

Therefore, until the surface of the roller 4 that slides on the rear head 8 passes through the capacity control port 9, the sealed space in the cylinder chamber 1a is connected to the suction side by the bypass passage 12, so that no compression occurs. Since a part of the refrigerant gas is returned to the suction side, control is performed to reduce the capacity.

Note that the surface of the roller 4 in sliding contact with the rear head 8 passes through the injection gas passage 1 after passing through the capacity control port 9 and until it further passes through the injection port 10.
1. The inner space of the cylinder chamber 1a is communicated with the bypass passage 12 by the cylinder chamber 15, but the injection gas passage 11 is narrow and has a large fluid resistance, and the side of the roller 4 that comes into sliding contact with the rear head 8 The cylinder chamber 1 until the surface reaches the injection port 10
The pressure rise in the internal space a is, for example, the suction side pressure 5 kg/
Since it is about 1.0 to 2.0Kg/cm ² per cm ² ,
The amount of gas flowing backward through the injection port 10 is very small;
Therefore, only the capacity control port 9 actually functions to reduce the output, and a predetermined capacity control operation determined by the position of the port 9 and the hole diameter is stably performed.

In this case, the constant rear chamber portion, which serves as a back pressure chamber for the piston valve 16, is only in communication with the sealed control passage 13, so there is no pressure fluctuation, and the piston valve 16 is not affected by the elastic force. Since the piston valve 16 is pushed up to the ultimate position, the piston valve 16 does not vibrate at all during the capacity control operation.
Therefore, there is no possibility that abnormal noise will occur.

On the other hand, when the load on the refrigeration system increases and it becomes necessary to increase the compressor output, the valve 19 is opened and the control passage 13 is supplied with an intermediate pressure of, for example, 12 to 13 kg/cm ^{2 .}
of gas refrigerant.

As a result, the pressure in the rear chamber part of the cylinder chamber 15 increases at all times, and back pressure that overcomes the elasticity of the coil spring 17 is applied to the piston valve 16. is pushed down and the valve tip closes the capacity control port 9, and the space in the cylinder chamber 1a and the bypass passage 12 are completely cut off, while the injection gas passage 11 is connected to the control passage 13 through the rear chamber. communicate.

Therefore, the intermediate pressure gas refrigerant is pumped from the injection port 10 to the cylinder chamber 1a depending on the pressure difference between the internal space of the cylinder chamber 1a at that time, for example, 0.6 to 7.0 kg/cm ² and the fluid resistance of the gas passage 11. Since the appropriate amount is injected into the refrigerant, the refrigerant gas with a high density is compressed and the output is increased.

In this case, the piston valve 16
Since the compressor is directly closed, there is no dead space that would reduce compression efficiency, resulting in efficient compression operation.

Although the present invention has been explained above using a rolling piston type rotary compressor, the present invention can also be applied to a sliding vane type rotary compressor in the same manner. It can constitute a rotary compressor.

(Effects of the Invention) As is clear from the above description, in the present invention, since the capacity control port 9 and the injection port 10 are provided independently, each hole diameter and position can be set as desired. Optimal design is possible to effectively increase or decrease output.

Furthermore, by providing the capacity control port 9 and the injection port 10 in relation to the control valve 14, it becomes possible to share the passage for bypass and for injection, and therefore the piping for capacity control can be shared. The system is simplified by requiring only the control passage 13, and costs are reduced due to a reduction in the number of parts.

In addition, what acts as back pressure on the piston valve 16 in the control valve 14 is only the intermediate pressure gas used for operation, and the configuration is such that it is not affected by the pressure in the cylinder chamber 1a during capacity control operation. This makes it possible to reliably prevent valve chattering and eliminate noise.

Furthermore, since the displacement control port 9 is directly closed by the piston valve 16, there is no dead space communicating with the cylinder chamber 1a, and compression efficiency can be maintained at a high level.

[Brief explanation of drawings]

Figures 1 and 2 are a plan view of the main parts of a conventional common port type compressor, a front view of the main parts shown in reverse, and Figs.
The figure is a plan view of main parts of a conventional individual passage compressor, FIGS. 4 and 5 are a plan view and front view of main parts of a conventional common passage compressor, and FIG. 6 is a plan view of main parts of a conventional common passage compressor. FIG. 7, which is a plan view of the main part of one example, is a front view of the main part shown in reverse and shows a capacity increasing operation state. FIG. 8, like FIG. 7, is a front view of the main parts shown in reverse, showing a reduced capacity operating state. 1...Cylinder, 1a...Cylinder chamber, 4...
Roller, 5... Suction passage, 6... Blade chamber, 7
... Blade, 8 ... Rear head, 9 ... Capacity control port, 10 ... Injection port, 11 ... Injection gas passage, 12 ... Bypass passage, 13 ... Control passage, 14 ... Control valve, 15 ... ...Cylinder chamber, 16...
piston valve.

Claims (1)

[Claims] 1 In a rotary compressor in which a capacity control port 9 and an injection port 10 are provided facing a closed space where the pressure increases in the compression process of the cylinder chamber 1a, an injection gas passage 11 communicating with the injection port 10; Bypass passage 1 communicating with suction passage 5
2, a control passage 13 through which intermediate pressure gas lower than the discharge pressure and higher than the suction pressure is supplied when increasing the capacity of the compressor, and a cylinder chamber whose one end communicates with the capacity control port 9; A piston valve 16 is slidably housed in the piston valve 15 .
The piston valve 1 is a control valve in which an elastic force is applied in a direction away from the capacity control port 9 to the piston valve 1.
a control valve 14 that opens the capacity control port 9 by separating from the capacity control port 9 due to the elastic force of 6 and closes the capacity control port 9 by contacting the capacity control port 9 against the elastic force; While arranging
When the piston valve 16 is separated from the capacity control port 9, the bypass passage 12 is connected to the cylinder chamber 15.
The control passageway 13
is always connected to the rear chamber, which is a space that exists on the rear chamber side opposite to the capacity control port 9 with respect to the piston valve 16 in the cylinder chamber 15 at the time of separation, and further,
The injection gas passage 11 is used to constantly supply intermediate pressure gas to the rear chamber portion, and the piston valve 16 is slid against the elastic force to the capacity control port 9 and brought into contact with the capacity control port 9. when connected to the rear chamber part that is always formed continuously with the rear chamber part on the rear chamber side,
A rotary compressor characterized in that both the passages 11 and 13 are brought into communication during this contact.