JPH0442682Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a refrigeration mechanism that can reliably cool a compressor and improve its performance.

[Prior Art] A conventional example will be explained with reference to FIG. FIG. 4 is a diagram showing a conventional refrigeration mechanism, and reference numeral 1 in the figure indicates a compressor. A condenser 2 is connected to the discharge side of the compressor 1, and a throttle mechanism 3 and an evaporator 4 are connected to the discharge side of the compressor 1.
are connected sequentially. The evaporator 4 is connected to the suction side of the compressor 1. A bypass pipe 5 is disposed between the condenser 2 and throttle mechanism 3, and the evaporator 4 and compressor 1.
This bypass piping 5 has a capillary reach tube 6.
is inserted.

According to the above configuration, the high temperature and high pressure refrigerant compressed by the compressor 1 flows in the direction shown by the arrow in the figure.
It flows into the condenser 2. After being condensed in the condenser 2, it is throttled by the throttle mechanism 3 and flows into the evaporator 4. After being evaporated in the evaporator 4, it is returned to the compressor 1 and compressed again.

On the other hand, a part of the refrigerant flows into the capillary reach tube 6 via the bypass pipe 5, is throttled, flows into the suction side of the compressor 1, and is used to cool the compressor 1.

[Problems to be solved by the invention] In the above configuration, when the displacement amount (piston area x process x revolutions per minute) of the compressor 1 is used with a large change, for example, the refrigeration mechanism of an inverter air conditioner When the capillary reach tube 6 is designed based on one design point of the displacement of the compressor 1, if the displacement differs greatly from the design point, The flow rate of refrigerant flowing through the capillary reach tube 6 is relatively larger than the flow rate of refrigerant flowing through the throttle mechanism 3. Therefore, there is a problem in that more refrigerant than is necessary for cooling the compressor 1 flows through the capillary reach tube 6, resulting in a reduction in the original cooling capacity. At the same time, there was a problem in that the refrigerant returned to the compressor 1 through the capillary reach tube 6 more intensely, reducing the durability of the compressor 1.

This invention was made based on the above points,
The purpose is to provide a refrigeration mechanism that can improve performance while maintaining the cooling function of the compressor.

[Means for Solving the Problems] That is, the refrigeration mechanism according to the present invention is a refrigeration mechanism in which a bypass circuit having a capillary reach tube connects a high-pressure liquid line of a refrigerant circuit and a suction side of a compressor. , P1, the compressor suction refrigerant pressure acting on one side of the bellows having a spring force F between the capillary reach tube provided in the bypass circuit and the connection part to the high pressure liquid line of the bypass circuit. P2 is the high pressure liquid refrigerant pressure that acts to push up the valve body provided on the other side of the bellows, P3 is the pressure in the bypass circuit that acts on the other side of the bellows through the capillary reach tube, and P2 is the pressure above. The present invention is characterized in that a pressure on/off valve is installed which opens under the condition of P1+F<a・P2+P3, where a is the effective cross-sectional area of the valve body receiving the pressure.

[Function] In other words, when the displacement of the compressor increases, that is, when the calorific value of the compressor increases, the differential pressure between the high-pressure liquid refrigerant pressure and the compressor suction refrigerant pressure increases, causing the pressure opening/closing valve to open. A portion of the refrigerant is supplied to the compressor via a bypass circuit to cool the compressor.

[Effect of the invention] Therefore, instead of a part of the refrigerant always being supplied to the compressor as in the past, the refrigerant is only supplied when the displacement of the compressor increases and the amount of heat generated increases. Part of the refrigerant can be supplied to the compressor via the bypass circuit, which not only ensures the cooling function of the compressor, but also stops the supply of unnecessary refrigerant.
Performance can be effectively improved. In particular, according to the present invention, the pressure opening/closing valve is configured to open directly according to the detected differential pressure.
It does not require any special power supply means or control system, has a simple configuration, and can be expected to operate with high reliability.
In addition, since the pressure on/off valve is opened directly by differential pressure, the response speed is faster compared to, for example, a system in which the temperature of the compressor is detected and then the solenoid valve is indirectly controlled. Accurate valve opening operation can be performed without time delay.

[Embodiment] A first embodiment of the present invention will be described below with reference to FIGS. 1 and 2. FIG. 1 is a diagram showing a refrigeration mechanism according to this embodiment, and reference numeral 101 in the figure indicates a compressor. A condenser 102 is connected to the discharge side of the compressor 101. Furthermore, this condenser 10
A throttle mechanism 103 and an evaporator 104 are sequentially connected to the compressor 2, and the discharge side of the evaporator 104 is connected to the suction side of the compressor 101. The condenser 102 and throttle mechanism 103, and the evaporator 104
Bypass piping 11 is connected between the compressor 101 and the compressor 101.
1 is arranged, and this bypass piping 111 has an on-off valve 112 and a capillary reach tube 11.
3 are inserted sequentially. The on-off valve 112 has a mechanism that opens and closes based on pressure, and is designated by the reference numeral 114 in the figure.
indicates the pressure introduction piping.

The on-off valve 112 is constructed as shown in FIG. FIG. 2 is a sectional view showing a schematic configuration of the on-off valve 112, and reference numeral 121 in the figure indicates the valve body. A bellows 122 is installed inside the valve body 121, dividing the interior of the valve body 121 into upper and lower halves. The pressure introduction pipe 114 is connected to the upper chamber 123, and the lower chamber 123 is connected to the pressure introduction pipe 114.
4 are connected to an inlet pipe 125 and an outlet pipe 126, respectively. These inlet pipe 125 and outlet pipe 126 are connected to the bypass pipe 111. Further, a ball 128 serving as a valve body is fixed to the center of the lower part of the bellows 122 via a support member 127. On the other hand, a valve seat 129 is fixed to the valve body 121 on the side facing the ball 128. These balls 128 and valve seat 12
9 constitute a valve. Pressure P1 acts on the upper surface of the bellows 122 through the pressure introduction pipe 114, pressure P2 acts on the upper surface of the bellows 122 through the inlet pipe 125, and pressure P2 acts on the upper surface of the bellows 122 through the outlet pipe 126.
Pressure P3 acts on the lower surface side of 2. The on-off valve 112 is opened and closed based on the relationship between these pressures. In this embodiment, it is assumed that the on-off valve 112 closes when P1+F≧a·P2+P3, and opens when P1+F<a·P2+P3.

Note that F is the spring force of the bellows 122, and a is the effective cross-sectional area of the ball valve 128.

The operation will be explained based on the above configuration. First, when the displacement of the compressor 101 is large, the high temperature and high pressure refrigerant compressed by the compressor 101 flows into the condenser 102 as shown by the arrow in the figure and is condensed.
It flows into the evaporator 104 via the throttle mechanism 103. It is evaporated in the evaporator 104, and the compressor 1 is re-evaporated.
01 and is compressed. The same cycle is repeated thereafter. At this time, the pressure loss of the refrigerant throttled by the throttle mechanism 103 is larger than when the displacement amount is small because the displacement amount of the compressor 101 is large. The pressure relationship at that time is P1+F<a.P2+P3, and the on-off valve 112 is opened. When the on-off valve 112 is opened, a part of the refrigerant condensed in the condenser 102 flows through the capillary reach tube 113 via the on-off valve 112 and is supplied to the compressor 101. The supplied refrigerant flows through a refrigerant circuit (not shown) of the compressor 101 to cool the compressor 101.

On the other hand, when the displacement of the compressor 101 is small, the pressure relationship is P1+F≧a·P2+P3, and as a result, the on-off valve 112 is closed. Therefore, no refrigerant is supplied to the refrigerant circuit of the compressor 101.

According to the refrigeration mechanism according to this embodiment, the following effects can be achieved.

(1) First, the on-off valve 112 is opened only when the displacement amount of the compressor 101 is large, in other words, when the calorific value of the compressor 101 is large, and refrigerant is supplied to the refrigerant circuit of the compressor 101. This makes it possible to effectively cool the compressor 101.

(2) On the other hand, when the displacement amount of the compressor 101 is small, that is, when the calorific value of the compressor 101 is relatively small, the on-off valve 112 is closed and the refrigerant is transferred to the refrigerant circuit of the compressor 101. Since the refrigerant is not supplied and all of the refrigerant flows in the direction of the evaporator 104, it is possible to effectively perform the cooling function, improve performance, and improve the durability of the compressor 101. It is possible to prevent a decrease in

The second embodiment will be described below with reference to FIG. FIG. 3 is a diagram showing a case where the refrigeration mechanism according to the present invention is applied to a so-called heat pump, and the reference numeral 131 in the figure indicates a compressor. An outdoor heat exchanger 133 is connected to the discharge side of the compressor 131 via a four-way switching valve 132, and a throttle mechanism 134 is connected to the discharge side of the compressor 131.
and an indoor heat exchanger 135 are connected.
The discharge side of this indoor heat exchanger 135 is connected to the four-way switching valve 132.

A branch pipe 136 is provided before and after the throttle mechanism 134.
and 137 are branch-connected. Check valves 138 and 139 are inserted into these branch pipes 136 and 137. These branch pipes 13
6 and 137 are connected to the collecting pipe 140.
The collecting pipe 140 is connected to the four-way switching valve 132, and a branch pipe 141 is branched from the middle thereof and connected to the compressor 131. Further, an on-off valve 142 and a capillary reach tube 143 are sequentially inserted into the collecting pipe 140. The on-off valve 142 is the same as that shown in the first embodiment, and its explanation will be omitted. Note that 1 in the figure
44 indicates a pressure introduction pipe.

The operation of the second embodiment having the above configuration will be explained. First, during cooling operation, the refrigerant is compressed by the compressor 131, and as shown by the solid line arrow in the figure, the refrigerant is compressed by the four-way switching valve 13.
2 into the outdoor heat exchanger 133. The refrigerant that has passed through the outdoor heat exchanger 133 flows into the indoor heat exchanger 135 via the throttle mechanism 134.
Further, the compressor 13
It returns to 1 and is compressed again.

On the other hand, during heating, the compressor 1
The refrigerant compressed at 31 flows into the indoor heat exchanger 135 via the four-way switching valve 132, as shown by the dashed arrow in the figure. The refrigerant that has passed through the indoor heat exchanger 135 flows into the outdoor heat exchanger 133 via the throttle mechanism 134, flows into the compressor 131 via the four-way switching valve 132, and is compressed again.

During the above-mentioned cooling/heating operation, if the refrigerant flow rate is large and the pressure loss is large until it is throttled by the throttle mechanism 134 and evaporated in the indoor heat exchanger 135 or outdoor heat exchanger 133 and sucked, , the pressure on-off valve 142 is opened, and a portion of the refrigerant is supplied to a refrigerant circuit (not shown) of the compressor 131;
The compressor 131 is cooled. On the other hand, when the refrigerant flow rate is small and the pressure loss is small, the pressure on/off valve 142 is closed. Therefore, no refrigerant is supplied to the refrigerant circuit of the compressor 131, improving performance.

As described above, also in the case of this second embodiment, only when the calorific value of the compressor 131 is large, a part of the refrigerant is supplied to the refrigerant circuit of the compressor 131 through the bypass circuit, and It is designed to cool down the air. Therefore, similarly to the first embodiment, the compressor 131 is cooled by cooling the compressor 131.
It is possible to effectively maintain both the health of the system and improve its performance.

A branch pipe 126 is provided before and after the throttle mechanism 123.
and 127 are branch-connected. Check valves 128 and 129 are inserted into these branch pipes 126 and 127. These branch pipes 12
6 and 127 collectively form 130.
The collecting pipe 130 is connected to the four-way switching valve 122, and a branch pipe 131 is branched from the middle thereof and connected to the compressor 101. Further, an on-off valve 132 and a capillary reach tube 133 are sequentially inserted into the collecting pipe 130. The on-off valve 132 is the same as that shown in the first embodiment, and its explanation will be omitted. Note that the reference numeral 134 in the figure indicates a pressure introduction pipe.

The operation will be explained based on the above configuration. First, during cooling operation, the refrigerant is compressed by the compressor 121, and as shown by the solid line arrow in the figure, the refrigerant is compressed by the four-way switching valve 122.
Flows into the outdoor heat exchanger 123 via. The refrigerant flowing through the outdoor heat exchanger 123 passes through the throttle mechanism 12
4 into the indoor heat exchanger 125, and further returns to the compressor 121 via the four-way switching valve 122, where it is compressed again.

On the other hand, during heating, the compressor 12
The refrigerant compressed in step 1 passes through the four-way switching valve 122 to the indoor heat exchanger 12, as shown by the broken line arrow in the figure.
5. The refrigerant that has passed through the indoor heat exchanger 125 flows into the outdoor heat exchanger 123 via the throttle mechanism 124, flows into the compressor 121 via the four-way switching valve 122, and is compressed again.

During the above-mentioned cooling/heating operation, when the refrigerant flow rate is large and the pressure loss is large until it is throttled by the throttling mechanism 124, evaporated in the indoor heat exchanger 125 or the outdoor heat exchanger 123, and sucked. In this case, the pressure on/off valve 132 is opened and a part of the refrigerant is supplied to a refrigerant circuit (not shown) of the compressor 121,
The compressor 121 is cooled. On the other hand, when the refrigerant flow rate is small and the pressure loss is small, the pressure on/off valve 132 is closed. Yotsute compressor 121
No refrigerant is supplied to the refrigerant circuit, improving performance.

As described above, in the case of the second embodiment as well, only when the amount of heat generated by the compressor 121 is large, a part of the refrigerant bypasses and is supplied to the refrigerant circuit of the compressor 121 to cool the compressor 121. Therefore, as in the first embodiment, it is possible to effectively maintain the health of the compressor 121 by cooling the compressor 121 and improve its performance.

[Brief explanation of the drawing]

1 and 2 are diagrams showing a first embodiment of the present invention, in which FIG. 1 is a diagram showing the configuration of the refrigeration mechanism, FIG. 2 is a cross-sectional view showing the configuration of the on-off valve in detail, and FIG. The figure shows the configuration of the refrigeration mechanism according to the second embodiment,
FIG. 4 is a diagram showing the configuration of a conventional refrigeration mechanism. 101... Compressor, 102... Evaporator, 103
... Throttle mechanism, 104 ... Evaporator, 111 ... Bypass piping, 112 ... Opening/closing valve, 113 ... Capillary reach tube.

Claims (1)

[Scope of Claim for Utility Model Registration] In a refrigeration system in which the high-pressure liquid line of the refrigerant circuit and the suction side of the compressor are connected by a bypass circuit having a capillary reach tube, A compressor suction refrigerant pressure acting on one side of the bellows having a spring force F is connected between the pillar reach tube and the connection part to the high pressure liquid line of the bypass circuit, and a valve body is provided on the other side of the bellows. The pressure of the high-pressure liquid refrigerant that acts to push up is P2, the pressure in the bypass circuit that acts on the other side of the bellows through the capillary reach tube is P3, and the effective cross-sectional area of the valve body that receives the pressure P2 is A refrigeration mechanism characterized in that a pressure opening/closing valve is installed that opens under the following conditions: P1+F<a・P2+P3, where a.