JPH09101064A - Stirling refrigerating apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To resolve the possibility of destruction of a joint portion between a heat conducting portion and a heat conducting plate by an excessively large force due to abnormal vibration. SOLUTION: A peripheral end portion 28a of a stationary table 28 of a Stirling engine is inserted in and held by a hollow portion 29a of a rubber vibration isolating member 29 having a cross-sectional shape of U, outer walls 29b of the rubber vibration isolating member 29 are held within a hollow portion 30a of a securing member 30 having a cross-sectional shape of U, and a protrusion 29c of the rubber vibration isolating member 29 is in contact with a bottom 30c of the securing member 30. A mounting portion 30d of the securing member 30 is secured to a bottom angle member 24 by a bolt 31.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a Stirling refrigerating apparatus for realizing an ultra-low temperature state in a freezer box by using a Stirling engine.

[0002]

2. Description of the Related Art A refrigeration system using a Stirling engine is relatively easy to maintain and absorbs heat when the working gas expands to cool the inside of the refrigeration box from about -60 ° C. to an ultra-low temperature of -200 ° C. to freeze blood, chemicals, etc. It is suitable for cooling products to ultra-low temperature and is about to be widely used in various fields.

4 and 5 are partial cross-sectional views showing the inside of a Stirling refrigerating apparatus of this type, which are roughly classified into a Stirling engine 1 and a freezing box 2.
The Stirling engine 1 is arranged on the fixed base 3, and the freezing box 2 is arranged above the Stirling engine 1.

The freezer box 2 has a box-shaped outer box 4 and an inner box 5.
A heat insulating material 6 such as urethane is filled between the inner wall and the inner wall of the inner box 5, and an aluminum plate having good heat conductivity is attached to the side wall as the heat conducting plate 7, while a heat conducting plate 8 is attached to the bottom wall. A refrigerating chamber 9 for accommodating a frozen product as a refrigerating load is formed on the inner side surrounded by the heat conduction plates 7 and 8, and a lid for taking in and out the frozen product is provided in a front portion of the freezing chamber 9. 10
Is provided.

Further, the freezing box 2 has a heat conducting portion 11 which is a cold head for conducting cold heat from the Stirling engine 1 at the lower portion, and one end side of the heat conducting portion 11 is connected to the tip of the expansion cylinder portion 12. The other end side is joined to the bottom surface of the heat conduction plate 8.

The Stirling engine 1 includes an expansion cylinder section 1
2 has a crank mechanism 13 below, and a compression cylinder portion 16 is fitted to the first piston 14 in the horizontal direction to form a compression chamber 17 in the forward direction, and a second piston 15 is fitted to the expansion cylinder portion 12. The expansion chamber 18 is formed on the other side. Further, the Stirling engine 1 includes a motor drive unit 19 as a prime mover that drives the crank mechanism 13, and an oil supply unit 20 that supplies lubricating oil to the crank mechanism 13.

The bottom of the Stirling engine 1 is fixed to a fixed base 3 which is a rectangular plate member by means not shown, and bolts 23 are inserted into bolt holes 22 formed at the four corners of the fixed base 3 as shown in FIG. It is fixed to a bolt hole 25 provided in a bottom angle 24 provided so as to penetrate therethrough and face it. The bottom angle 24 is a rectangular reinforcing frame body corresponding to the fixed base 3, and the caster 26 is attached to the bottom angle 24.
There are four vertical angles (not shown) extending upward from the four corners of the above, and the whole is formed by angles, and the freezing box 2 is fixed to these angles.

With the above structure, when the motor drive unit 19 is driven, the crank mechanism 13 of the Stirling engine 1 causes the first piston 14 and the second piston 15 to reciprocate with a certain phase difference. First, the first piston 14 moves toward the end of the compression cylinder portion 16 to compress the working gas such as helium that fills the compression chamber 17, and the working gas that is compressed and generated heat is radiated by a radiator (not shown) to be illustrated. It is guided to the expansion chamber 18 after being further cooled by the heat regenerator. After that, the working gas in the expansion chamber 18 expands due to the lowering of the second piston 15, the working gas expands to lower the working gas temperature, cools the heat conducting portion 11, and then the second piston The rise of 15 pushes out the low-temperature working gas in the expansion chamber 18 and guides it to the compression chamber 17 while cooling the heat regenerator.

The above steps are repeated in sequence to expand the expansion chamber 18
Of the working gas of the expansion cylinder part 12 at the time of expansion
1, so that the heat conducting portion 11 gradually lowers the temperature of the freezing chamber 9 of the freezing box 2 via the heat conducting plates 7 and 8, and by repeating this, the upper portion of the heat conducting portion 11 of the expansion chamber 18 is increased. Is about −200 ° C. Freezing heat is transmitted from the heat conducting portion 11 via the heat conducting plate 8 to the freezing chamber 9 so that the central portion has a temperature of about −180 ° C. In addition, the freezer room 9
Refrigerating heat is transferred from the heat conducting portion 11 to the inner periphery by the heat conducting plate 7 via the heat conducting plate 8 and is lower than the central portion by about −.
It is set to 190 ° C. As a result, frozen objects such as blood, chemicals and various bacteria can be stored in the freezer compartment 9 at an ultralow temperature.

[0010]

By the way, in the Stirling refrigerating apparatus shown in FIGS. 4 to 6, the Stirling engine 1 is fixed to the fixed base 3 and the heat conducting portion 11 is attached to the heat conducting plate 8 of the freezing box 2, for example. Are joined with bolts,
There was a possibility that the joint between the heat conducting portion 11 and the heat conducting plate 8 would be broken due to the abnormal vibration of the Stirling engine 1.

That is, in order to efficiently transfer the cold heat from the Stirling engine 1 to the freezing box 2, the heat conducting portion 11 must be in close contact with the bottom surface of the heat conducting plate 8. On the other hand, the Stirling is required. As shown in FIG. 6, the engine 1 itself is fixed to the fixed base 3, and the fixed base 3 is firmly fixed to the bottom angle 24 by the bolt 23.

Due to this structure, when abnormal vibration occurs due to the driving of the crank mechanism 13 of the Stirling engine 1, this abnormal vibration is transmitted to the joint between the heat conducting portion 11 and the heat conducting plate 8 and heat is generated by the resonance phenomenon. There is a risk of breaking the joint between the heat conducting plate 11 and the heat conducting plate 8 and also a noise source.

Therefore, an object of the present invention is to provide a Stirling refrigeration system which prevents the occurrence of abnormal vibrations and prevents the destruction of each part in the Stirling refrigeration system due to the abnormal vibrations.

[0014]

According to a first aspect of the present invention, an expansion stroke of a working gas introduced from a compression chamber formed in a front portion of a compression cylinder portion to an expansion chamber formed in a front portion of an expansion cylinder portion is controlled. A heat conduction part for fixing the Stirling engine, which generates cold heat by a cycle process including at least, to the bottom frame via a fixing base, and a heat conduction plate provided on the bottom of the freezing chamber for conducting the cold heat generated in the expansion chamber. In the Stirling refrigerating device that is joined to the Stirling refrigerating device that connects the refrigerating box that cools the refrigerating load in the freezing chamber by conducting cold heat to the heat conducting plate and fixing it to the side frame, the fixing base is a vibration-proof rubber member. It is arranged so as to be fixed to the bottom frame by a fixing member. With the above configuration, even if the Stirling engine causes an abnormal vibration, the vibration of the fixing base is absorbed by the vibration isolating rubber member, the resonance state is avoided, and the joint between the heat conducting portion and the heat conducting plate is destroyed by an excessive force. It can eliminate the risk of

According to a second aspect of the present invention, in the Stirling refrigerating apparatus according to the first aspect, the fixing base is made of a material having a good thermal conductivity and radiates the heat generated by the Stirling engine to the outside. With the above configuration, the heat of the Stirling engine is released from the fixed base, and the thermal efficiency can be improved.

According to a third aspect of the present invention, a predetermined gap is formed in the concave portion of the fixing member with which the horizontal end of the anti-vibration rubber member abuts so that the fixing position of the fixing base can be moved in the horizontal direction. This is to ensure the joining of the heat conducting plate and the heat conducting portion. With the above configuration, the heat conductive plate and the heat conductive portion are securely bonded to each other, so that the bonded portion is strong and cold heat can be efficiently conducted.

[0017]

1 and 2 are partial cross-sectional views of a Stirling refrigerating apparatus showing an embodiment of the present invention, in which the same reference numerals as those in FIGS. The Stirling engine 1 is fixed on a fixed base 28, and the heat conducting section 11 at the upper part of the Stirling engine 1 and the bottom surface of the heat conducting plate 8 of the freezing box 2 are joined to each other. The heat conduction plate 8 is configured to be able to conduct cold heat.

The freezing box 2 is a box-shaped outer box 4 and an inner box 5.
A heat insulating material 6 such as urethane is filled between the outer wall and the outer wall of the outer box 4, and a plate having good heat conduction is attached to the side wall as the heat conductive plate 7 while a heat conductive plate 8 is attached to the bottom wall. A refrigerating chamber 9 for accommodating a frozen product as a refrigerating load is formed on the inner side surrounded by the heat conduction plates 7 and 8, and a lid for taking in and out the frozen product is provided in a front portion of the freezing chamber 9. 10 are provided.

The fixed base 28 of the Stirling engine 1 is a rectangular plate member that covers the bottom surface of the Stirling engine 1 and supports the Stirling engine 1. The edge portions 28a on both sides shown in FIG. 1 among the edge portions are fixed to the bottom angle 24 by a fixing member 30 with a vibration-proof rubber member 29 interposed. Specifically, as shown in FIG. 3, the edge 28a of the fixed base 28 is
Is sandwiched by the recesses 29a of the anti-vibration rubber member 29 having a U-shaped cross section, and the outer wall 29b of the anti-vibration rubber member 29 is formed in the opposing recessed portion 3 of the U-shaped fixing member 30.
The protrusion 29c of the anti-vibration rubber member 29 abuts on the bottom 30c of the fixed member 30. The attachment portion 30d of the fixing member 30 is attached to the bottom angle 24 by the bolt 31.

The bottom angle 24 has a bent portion 32a formed at the lower end of an angle 32 extending upward, and the four angles 32 as reinforcing frames from the bottom angle 24 surround the entire apparatus. A frame is formed, and the exterior panel 33 and the freezer box 2 are attached to the angle 32.

With the above construction, when the Stirling engine 1 vibrates due to the drive of the crank mechanism 13 of the Stirling engine 1, the vibration is transmitted to the fixed base 28 for fixing the Stirling engine 1. In this case, the vertical vibration causes the fixed base 28
The vibration-proof rubber member 29 interposed in the end edge portion 28 a of the fixing base 28 absorbs the horizontal vibration, and the vibration-proof rubber member 29 interposed in the end edge portion 28 a of the fixed base 28 absorbs the horizontal vibration. A gap between the protrusion 29c of the anti-vibration rubber member 29 and the bottom 30c of the fixing member 30 is provided to facilitate positioning when the fixing base 28 is attached.

As a result, even if the Stirling engine 1 itself undergoes abnormal vibration, the resonance state is avoided, and no excessive force acts on the joint between the heat conducting portion 11 and the heat conducting plate 8 of the Stirling engine 1. Therefore, the possibility that the joint between the heat conducting portion 11 and the heat conducting plate 8 is destroyed due to the abnormal vibration of the Stirling engine 1 is eliminated. If the fixing base 21 is made of a material having good thermal conductivity, for example, aluminum, the fixing base 2
Heat can be dissipated from below 8 toward the bottom, improving energy efficiency.

[0023]

As described above, according to the first aspect of the invention, since the fixing base is fixed to the bottom frame by the fixing member with the vibration isolating rubber member interposed, the Stirling engine causes abnormal vibration. However, the vibration-proof rubber member can absorb the vibration of the fixed base, the resonance state can be avoided, and the risk that the joint portion between the heat conducting portion and the heat conducting plate is destroyed by an excessive force can be eliminated.

According to the second aspect of the present invention, the heat generated by the Stirling engine is discharged to the outside by using a material having good heat conduction for the fixing table, so that the heat generated by the Stirling engine is discharged from the fixing table, and the heat efficiency is improved. Can be improved.

According to the third aspect of the present invention, since the fixing position of the fixing base can be moved in the horizontal direction to ensure the joint between the heat conducting plate and the heat conducting portion, the joint portion becomes strong, and the cold heat Can be efficiently conducted.

[Brief description of the drawings]

FIG. 1 is a partial front sectional view of a Stirling refrigerating apparatus showing an embodiment of the present invention.

FIG. 2 is a side partial cross-sectional view of the Stirling refrigerating apparatus of FIG.

FIG. 3 is an enlarged partial sectional view showing a main part of the Stirling refrigerating apparatus of FIG.

FIG. 4 is a partial front sectional view corresponding to FIG. 1, showing a conventional Stirling refrigerating apparatus.

5 is a side partial cross-sectional view of the Stirling refrigerating apparatus of FIG.

FIG. 6 is an enlarged partial cross-sectional view showing how the fixed base and the bottom angle of FIG. 4 are attached.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Stirling engine 2 Freezing box 4 Outer box 5 Inner box 7,8 Heat conduction plate 9 Freezing room 11 Heat conduction part 12 Expansion cylinder part 13 Crank mechanism 14 First piston 15 Second piston 16 Compression cylinder part 17 Compression chamber 18 Expansion chamber 19 Motor Drive Part 24 Bottom Angle 28 Fixing Base 28a End Edge 29 Anti-Vibration Rubber Member 29a Recess 29b Outer Wall 29c Projection 30 Fixing Member 30a Recess 30c Bottom 30d Attachment 31 Bolt 32 Angle 32a Bending

Claims (3)

[Claims] Claim: What is claimed is: 1. A Stirling engine that produces cold heat by a cycle stroke including at least an expansion stroke of a working gas guided from a compression chamber formed in a front portion of a compression cylinder portion to an expansion chamber formed in a front portion of an expansion cylinder portion. Is fixed to the bottom frame through a fixing base for fixing the heat conduction plate provided on the bottom surface of the freezing chamber to the heat conduction part for conducting the cold heat generated in the expansion chamber, and the cold heat is transmitted to the heat conduction plate. In a Stirling refrigerating device that fixes a freezing box that conducts to and cools a refrigerating load in a freezing chamber to a side frame that is connected to the bottom frame, the fixed base is a bottom frame with a vibration-proof rubber member interposed. A Stirling refrigerating apparatus which is fixed by a fixing member. 2. The Stirling refrigerating apparatus according to claim 1, wherein the fixing table is made of a material having a good thermal conductivity and radiates heat generated by the Stirling engine to the outside. 3. The heat generated by horizontally moving the fixing position of the fixing base by forming a predetermined gap in the concave portion of the fixing member with which the horizontal end of the vibration isolating rubber member abuts. The Stirling refrigerating apparatus according to claim 1 or 2, characterized in that the conduction plate and the heat conduction portion are securely joined together.