JPS62223576A - Reverse stirling cycle refrigerator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to improvements in reverse Stirling cycle refrigerators.

(Prior Art) Conventionally, there is a mechanism that connects a reverse Stirling cycle component to a buffer 7 tank that communicates with the crankcase via a filter when the motor that drives the crankshaft stops driving.

FIG. 3 shows a case where such a conventional mechanism is applied to a refrigerator consisting of two inverted Stirling cycle components operating with a phase difference of 180 degrees and using a diaphragm 24 as an oil sealing mechanism.

A working space consisting of an expansion space 18.18', a regenerator 19.19', a heat exchanger 20.20'' and a compressed air 17!121.21' communicates with the buffer tank 23 via an on-off valve 22.22'. When the motor drive is stopped, the above-mentioned valves 22 and 22' are opened, and the buffer tank 23 becomes a dead volume of the working space, so the driving force for reverse rotation is reduced and reverse rotation is prevented. Incidentally, as is well known, the crankshaft 25 is rotationally driven by a motor 26.

(Problem to be solved by the invention) In the case of a conventional reverse Stirling cycle refrigerator, in order for the reverse rotation prevention device to work reliably and effectively, the dead volume must be sufficiently large and the output of the Stirling cycle must be reduced. It is necessary to.

Another necessary condition is that the pressure in the buffer tank 7 rises at the same time as the on-off valve opens, creating a pressure difference between the top and bottom of the diaphragm, so the pressure limit in the buffer tank must be suppressed to protect the diaphragm. It is. In order to meet these conditions, it is necessary to make the buffer tank larger.

It is an object of the present invention to provide a reverse Stirling cycle refrigerator that does not have the above-mentioned problems and can more reliably prevent reverse rotation.

[Structure of the Invention] (Means for Solving the Problems) The reverse Stirling cycle refrigerator of the present invention includes at least two reverse Stirling cycle components having reciprocating members that operate with a predetermined phase difference, and the plurality of reverse Stirling cycle components. Drive the reverse Stirling cycle component! a common drive source that communicates the plurality of reverse Stirling cycle components;
It is characterized by comprising at least one on-off valve member disposed on the communication path and an actuating member that opens and closes the on-off valve member in conjunction with control by the drive source.

The present invention is characterized by a configuration in which at least two reverse Stirling cycle components that operate with a phase difference of, for example, 180 degrees are communicated with each other via at least one on-off valve. In other words, by configuring the on-off valve to open when the motor drive is stopped, when the on-off valve is open, the volume of both reverse Stirling cycle components changes with a phase difference of 180 degrees, so the overall volume There is no fluctuation, and therefore the formation of a Stirling cycle after the motor is stopped, that is, the occurrence of reverse rotation, can be reliably prevented.

Here, the predetermined phase difference means that in the case of a two-stroke Stirling engine, each expansion piston in each working space (or cylinder) reciprocates with a phase difference of 180 degrees, and in the case of a four-stroke engine, the expansion pistons in each working space (or cylinder) reciprocate with a phase difference of 180 degrees. This means that the relationship is such that two phase differences are superimposed.

The reciprocating member refers to at least one set of expansion or compression pistons. A phase difference of, for example, 180 degrees is provided between each pair of expansion pistons or compression pistons in this way, and the pistons are configured to perform forward movement 411+ with this phase difference.

The reverse Stirling cycle component is a Stirling engine whose constituent units are an expansion space, a compression space, a regenerator, a heat exchanger, an expansion piston, and a compression piston.

A working gas space is a plant or space of variable volume in which high-pressure or low-pressure gas accumulates.

A communication path is a gas transfer path that allows both working gas spaces to communicate with each other in order to allow working gas such as helium or neon to move freely from one working gas space to the other working gas space. It is.

The term "opening valve member" refers to a valve or a valve that is opened and closed by hydraulic or electric means.

The operating member of the opening/closing valve member is a member that opens and closes the valve in conjunction with control of the crankshaft drive motor, and may be of either a hydraulic type or an electric type.

(Operation) Driven by the motor that is the drive source, the compression piston moves up and down with a phase delay of about 90 degrees from the expansion piston, the working gas space forms a reverse Stirling cycle, and refrigeration occurs in the expansion space. Note that the expansion pistons move up and down with a phase difference of 180 degrees. Both working gas spaces are connected to each other by a valve through a communication path, and the valve is electrically closed and opened when the motor drive is stopped. As a result, after conduction, there is no change in the overall volume, so a Stirling cycle is not formed, and therefore, reverse rotation can be prevented.

(Embodiments of the Invention) (Actual Flow Example) A schematic diagram of a first embodiment of the reverse Stirling cycle refrigerator of the present invention is shown in FIG.

The expansion space 3.3' formed by the expansion cylinder 1.1- and the expansion piston 2.2' is connected to the compression cylinder 6.6- and the compressor via a regenerator 4.4'', a heat exchanger 5.5- It communicates with a compression space 8.8- formed by the piston 7.7' and forms an inverted Stirling cycle component in each case.

Through the crankshaft 10 by the drive of the motor 9,
The compression piston 7.7' is approximately 9
Moving up and down with a 0 degree phase lag, the reversed Stirling cycle component produces a reversed Stirling cycle and generates refrigeration in the expansion space 3.3'.

The crank positions were determined so that the expansion pistons 2 and 2-, which are reciprocating members, operated with a phase difference of 180 degrees.

Each of the above-mentioned reverse Stirling cycle components has a communication path 1.
1.12, communication was established via a valve 13, which is an on-off valve member. The valve 13 is electrically controlled by an operating member (not shown) and is configured to be opened when the motor 9 stops driving. Note that the valve 13 may be driven hydraulically instead of electrically. When the motor is stopped, when the communication passage 11.12 is brought into conduction by opening the valve 13, no change in volume occurs in the reverse Stirling cycle component as a whole, so the Stirling cycle does not occur. In this way, reverse rotation can be reliably prevented by the action of the single valve 13 without requiring the conventionally required buffer tank.

Furthermore, according to this embodiment, before and after the valve 13 is actuated,
Since no pressure difference occurs between the upper and lower portions of the diaphragm 14, the device of this embodiment can also be applied to a type of refrigerator that uses a diaphragm to seal oil.

(Second Embodiment) FIG. 3 shows a schematic diagram of a second embodiment of the reverse Stirling cycle refrigerator according to the present invention.

In this embodiment, each reverse Stirling cycle component is removed, and valves 15 and 16, which are 17I valve closing members, are placed near each working gas space, and each working gas space is connected to a communication path 17 through these valves. communicated by. According to this system, it is possible to minimize the increase in dead volume due to the addition of a reverse rotation prevention device in the working gas space, so that reverse rotation prevention can be achieved without sacrificing refrigeration performance.

It is clear that it is possible to reduce the starting torque at the time of starting the motor by using the above-mentioned reverse rotation prevention device.

[Effects of the Invention] According to the present invention, when the motor is stopped, problems such as abnormally high pressure, running out of oil in the drive section, and roughening of the surface of the crank bin metal due to reversal of the rotational direction can significantly impair the durability of the refrigerator. Reversal can be easily and reliably prevented with a simple configuration consisting of a combination of a communication path and a valve without requiring a buffer tank at all.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a first embodiment of the present invention, and FIG. 2 is a schematic diagram of a second embodiment of the present invention. FIG. 3 is a schematic diagram showing a conventional reverse rotation prevention device. 1.1'...Expansion cylinder 2.2-...Expansion piston 3.3'...Expansion space 4.4-...Regenerator 5.5-...Heat exchanger 6.6' ... Compression cylinder 7.7'... Compression piston 8.8'... Compression space 9... Motor 10... Crankshaft 11.12.17... Communication passage 13.15.16. ...Valve (opening/closing valve member) Patent applicant Aisin Seiki Co., Ltd. Agent Patent attorney
Hirodo Okawa Patent Attorney Akio Maruyama Figure 7 7? Figure 2

Claims (3)

[Claims] (1) At least two reverse Stirling cycle components having reciprocating members that operate with a predetermined phase difference, a common drive source that drives the plurality of reverse Stirling cycle components, and the plurality of reverse Stirling cycle components An inverted Stirling ring comprising: a communication path that communicates with the communication path; at least one on-off valve member disposed on the communication path; and an actuating member that opens and closes the on-off valve member in conjunction with control by the drive source. cycle refrigerator. (2) The reverse Stirling cycle refrigerator according to claim 1, wherein the predetermined phase difference is 180 degrees. (3) The reverse Stirling cycle refrigerator according to claim 1, wherein the operating member of the opening/closing valve member includes a hydraulic type, electric type, etc. control means.