JP2002295388A - Pump for sterling thermal equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent seizure of a bearing by keeping an underwater bearing to support a rotary shaft of an impeller of a pump in a consistently immersed condition in cooling water. SOLUTION: The rotary shaft 41 for rotating the impeller 45 is supported by submerged bearings 43 and 44 inside a pump casing 38, and a cooling water circulating piping 50 to connect a rear opening 51 of the pump casing 38 to a suction side pipe 49 connected to a suction port 46 is provided, and the submerged bearings 43 and 44 are constantly immersed in the cooling water while the pump P1 is in operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pump for feeding a liquid, and more particularly to a pump for circulating cooling water for radiating heat in a radiating heat exchanger (high-temperature heat exchanger) such as a Stirling refrigerator.

[0002]

2. Description of the Related Art In recent years, as a refrigeration system that substitutes CFCs for global environmental problems, the operating temperature of the refrigeration system is wider than that of conventional refrigeration systems. , Low-temperature liquid circulators, low-temperature thermostats, thermostats, heat shock testers, freeze dryers, temperature characteristic testers, blood / cell storage devices, cold coolers, and various other types of cooling and heating devices. A Stirling refrigerator has been in the spotlight as a refrigerator that can be applied to cold heat equipment, is compact, has a high coefficient of performance, and has good energy efficiency.

In such a Stirling heat apparatus such as a Stirling refrigerator, a working gas flows between a compression chamber (high-temperature chamber) and an expansion chamber (low-temperature chamber) of a working cylinder, and is disposed along the flow path. The heat-exchanging heat exchanger (low-temperature heat exchanger) and the heat-dissipating heat exchanger (high-temperature heat exchanger) exchange heat with the cold refrigerant and the cooling water, respectively.

[0004]

The radiating heat exchanger is connected to a radiator (radiator) through a cooling water circulation pipe and a cooling water pump, and is configured to circulate the cooling water. . The inside of the main body housing of the cooling water pump is immersed in the cooling water, and the cooling water lubricates and cools the bearing of the rotary shaft of the pump. However, when the amount of cooling water in the main body housing is reduced, the flow of the cooling water is unstable, or a lot of air bubbles are mixed (this is referred to as "air biting"), it hinders lubrication and cooling of the bearing. Therefore, seizure of the bearing occurs.

SUMMARY OF THE INVENTION An object of the present invention is to solve such a conventional problem. A bearing in a cooling water pump is always immersed in cooling water.
An object of the present invention is to prevent a bearing from burning and to obtain a stable and good heat radiation heat exchanger. In addition, this problem does not occur only in the pump for cooling water of the heat exchanger for heat radiation such as a Stirling refrigerator, but is a problem generally occurring in pumps having such a submerged bearing. Issues.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a pump body and a liquid feed section located at a front end of the pump body and having a suction port, an impeller rotation chamber, and a discharge port. A pump comprising: the impeller is attached to a front end of a rotating shaft driven by a motor;
The rotary shaft is supported by a submerged bearing in the pump body, connects a rear opening of the pump body and a suction-side pipe, and is provided with a liquid reflux pipe for refluxing the liquid,
A pump is provided, wherein the submerged bearing is always immersed in the liquid during operation of the pump.

[0007] In order to solve the above-mentioned problems, the present invention is a pump comprising a pump body, and a delivery section located at a front end of the pump body and having a suction port, an impeller rotation chamber, and a discharge port. The impeller is attached to a front end of a rotary shaft driven by a motor, and the rotary shaft is supported by a submerged bearing in the pump body, and an opening at a rear portion of the pump body and a discharge side pipe are provided. A liquid recirculation line for recirculating the liquid is provided.
A pump is provided, wherein the submerged bearing is configured to be constantly immersed in the liquid.

[0008] A throttle is provided in the liquid reflux line.

An accumulator is provided in the liquid reflux line.

An on-off valve is connected to the liquid reflux line.

The liquid is cooling water circulated between the heat radiating heat exchanger and the radiator, and the pump is a cooling water pump for circulating the cooling water. .

The above-mentioned heat-exchanging heat exchanger is a heat-exchanging heat exchanger for working gas of a Stirling refrigerator.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on embodiments with reference to the drawings. FIG. 1 is a diagram illustrating the overall structure of a Stirling refrigerator 1 which is an example of a Stirling heat device according to the present invention. The housing 2 of the Stirling refrigerator 1 is integrally formed of a casting, and the inside thereof is semi-sealed. The interior of the housing 2 is partitioned into a motor chamber 4 and a crank chamber 5 by a partition wall 3.

A motor 6 capable of normal and reverse rotation is provided in the motor chamber 4.
An opening for maintenance is formed, and a lid 7 for hermetically sealing the opening is fixed by a bolt or the like via a metal seal 8. An opening for a motor power supply is formed in the top wall 9 of the motor chamber 4, the opening is hermetically closed, and the terminal cover 1 to which the power supply mounting terminal 10 is attached.
1 is detachably attached via a metal seal 8.

An opening for a bearing is formed at an end of the crank chamber 5, and a bearing mounting lid 12 provided with a bearing on the inner surface so as to hermetically close the opening is detachably mounted via a metal seal 8. Have been. Further, openings are formed at the bottom of the crank chamber 5 for charging and maintenance of the equipment, and the bottom cover 1 is sealed so as to hermetically seal these openings.
3 is detachably attached via a metal seal 8.

A crankshaft 14, which is driven by a motor 6 and converts the rotation of the motor 6 into reciprocating motion, two connecting rods 15, and two cross guide heads 16 are arranged in the crank chamber 5, and are provided with a Stirling refrigerating machine. The drive mechanism of the machine 1 is configured. The two crank portions 17 and 18 of the crankshaft 14 are formed with a phase difference so that the crank portion 17 moves ahead of the crank portion 18 when the motor 6 rotates forward. As this phase difference, a phase difference of about 90 degrees is generally adopted.

A compression cylinder block 19 is fixed to the upper part of the crank chamber 5 via a metal seal 8 in an airtight manner with respect to the housing 2. The compression cylinder block 19 has an opening 23 for communicating with the expansion cylinder. Further, on the compression cylinder block 19, an expansion cylinder block 20 is hermetically fixed by bolts or the like via a metal seal 8.

The compression cylinder block 19 and the compression cylinder block 20 are used for the compression cylinder 21 and the expansion cylinder 2 which are the working cylinders of the Stirling refrigerator 1, respectively.
2. Compression cylinder 21 and expansion cylinder 2
For example, helium, hydrogen, nitrogen, or the like is sealed as a working gas in the housing 2 and the housing 2. A compression piston 26 reciprocates in the compression cylinder 21. The upper part (compression space) of this space is the high temperature chamber 24, in which the working gas is compressed to a high temperature.

The compression piston rod 25 connects the compression piston 26 and the cross guide head 16 and extends through the compression cylinder 21 and an oil seal 29 in a through hole in the top wall of the crank chamber 5. Since the sliding direction of the reciprocating compression piston 26 is reversed at the top dead center and the bottom dead center, the speed becomes zero, and the speed is slow near the top dead center and the bottom dead center, and the change amount of the volume per unit time is also small. When moving from the bottom dead center to the top dead center and from the top dead center to the bottom dead center, the speed becomes the maximum at each intermediate point, and the compression piston 26 per unit time
The amount of change in volume due to the movement of is also maximum.

The expansion piston rod 27 connects the expansion piston 28 and the cross guide head 16, and the expansion cylinder 22 and an oil seal 29 in a through hole in the top wall of the crank chamber 5.
Extends through. The expansion piston 28 reciprocates and slides in the space of the expansion cylinder block 20, and the upper part (expansion space) of this space is a low-temperature chamber 30, in which the working gas expands to a low temperature. The expansion piston 28 moves ahead of the compression piston 26 by a phase of 90 degrees.

The expansion cylinder block 20 is provided with a manifold 31 through which a working gas flows into and out of the compression space of the compression cylinder 21. The manifold 31 further includes a heat-dissipating heat exchanger (high-temperature-side heat exchanger) 32. A regenerator 33 and a heat exchanger for cooling (low-temperature heat exchanger) 34 are annularly arranged so as to communicate with each other sequentially. Compression cylinder block 19
A communication hole 23 that connects the high temperature chamber 24 and the manifold 31 is formed near the upper end portion of the communication hole 24.

The radiating heat exchanger 32 is connected to the cooling water circulation line 3.
5 and a radiator 36 via a cooling water pump P1 to circulate the cooling water. As the cooling water, water or dilution water obtained by mixing ethylene glycol or polyethylene len glycol with water is used.

In the Stirling refrigerator 1 having such a configuration, the characteristic configuration of the present invention is that the cooling water pump P provided in the cooling water circulation line 35 of the heat exchanger for heat radiation is used.
1 is provided so that the above-described air biting does not occur.

FIG. 2 is a diagram showing a configuration of a cooling water pump P1 body used in the present invention. Pump P1 for cooling water
Has a pump body 38 and a casing 38 '.
A motor stator 39 is provided in the pump body 38, and a rotor can 43 is fixedly provided inside the stator 39. A rotor 40 of the motor is mounted in the rotor can 43 so as to be rotatable about a rotation shaft 41. The rotary shaft 41 is supported by submerged bearings (usually referred to as “submerged bearings” and using carbon bearings or the like) 44 before and after the pump body 38.

An impeller (impeller) is provided at the front end of the rotating shaft 41.
45 is fixed. The casing 38 'is attached to the front end of the pump body 38 in a watertight manner, forms the suction port 46, the impeller rotation chamber 47 and the discharge port 48, and functions as a liquid sending section.

The cooling water is sucked through the suction port 46, flows into the pump P1, and is sent out from the discharge port 48 by the centrifugal force of the impeller 45. The inside of the pump body 38 of the cooling water pump P1 is immersed in cooling water, and the cooling water lubricates and cools the bearing. Therefore, in the conventional cooling water pump, if such cooling water in the pump body 38 is reduced or a large amount of air bubbles are mixed (such a phenomenon is referred to as “air biting”), the bearing is lubricated. As a result, the bearings are burned to prevent cooling.

The cooling water pump according to the present invention is arranged so as to prevent air biting. FIG. 3 (a) shows an embodiment of the present invention, in which a cooling water recirculation pipe for connecting a pump body 38 of the cooling water pump P1 and a suction side pipe 49 connected to the suction port 46 to each other is provided. 50) is provided so that cooling water is constantly circulated and filled in the pump body 38 to prevent the bearing 44 from burning.

As shown in FIG. 3A, the cooling water pump P1 has an opening 51 at the rear of the pump body 38 at the rear of the mounting portion of the bearing 44 at the rear of the cooling water pump P1.
To form The inlet end of the cooling water recirculation pipe 50 is attached to the opening 51 via the throttle 52, and the outlet end of the cooling water recirculation pipe 50 is attached to the suction port 46. The accumulator 55 may be connected to the cooling water recirculation line 50 as necessary to obtain a stable flow in the cooling water recirculation line 50.

FIG. 3B shows a modification of the cooling water pump P1 according to the embodiment of the present invention.
And the opening 51 at the rear of the cooling water pump P1 is connected so as to communicate with the cooling water reflux pipe 50.

FIGS. 4 (a) and 4 (b) show another embodiment of the present invention. In FIGS. 3 (a) and 3 (b), instead of the accumulator 55, cooling water reflux pipes 50 and 53 are provided. , The on-off valve 56 is connected. The capacity up to the on-off valve 56 is appropriately designed, and the on-off valve 56 is closed during the operation of the Stirling refrigerator and serves as a reservoir tank. Use.

The operation of the Stirling refrigerator 1 according to the embodiment having the above-described configuration will be described. The motor 6 rotates the crankshaft 14 in the forward direction, and the crank portions 17 and 18 in the crank chamber 5 rotate with a phase shift of 90 degrees. A cross guide head 16 is connected via a connecting rod 15 rotatably connected to the crank portions 17 and 18.
Reciprocates. A compression piston 26 and an expansion piston 28 connected to the cross guide head 16 via a compression piston rod 25 and an expansion piston rod 27, respectively.
Reciprocate with a phase difference of about 90 degrees from each other.

While the expansion piston 28 moves slowly near the top dead center in advance, the compression piston 26 rapidly moves toward the top dead center near the middle to perform the operation of compressing the working gas. The compressed working gas flows into the heat dissipation heat exchanger 32 through the communication hole 23 and the manifold 31. The working gas radiated to the cooling water by the radiating heat exchanger 32 is supplied to the regenerator 33.
And flows into the low-temperature chamber (expansion space) 30 through the cooling heat exchanger 34, where it expands rapidly and generates cold heat. The head of the expansion cylinder 21, that is, the cold head 53 is cooled to a low temperature.

Then, in the cold head 53, the cold refrigerant in contact with the cooling fins 54 of the cooling heat exchanger 34 is cooled. When the expansion piston 28 moves from the bottom dead center to the top dead center, the compression piston 26 moves from the intermediate position to the bottom dead center, and the working gas passes from the low-temperature chamber 22 through the cooling heat exchanger 34 to the regenerator 33. Into the regenerator 33. The cool heat stored in the regenerator 33 is transferred from the high-temperature chamber 24 to the heat-radiating heat exchanger 3 as described above.
The working gas sent through 2 is recycled for cooling again.

Then, the cold refrigerant cooled in the cold head 53 cools various cold utilization devices. For example, the cold refrigerant is sent to a cold refrigerant pipe in a cold utilization device such as a freezer, and performs freezing or cooling in the cold utilization device. It is circulated back to the cold head 53 and cooled again.

The cooling water having undergone heat exchange in the heat radiating heat exchanger 32 flows from the cooling water circulation line 35 to the radiator 36, where it is cooled by the cooling fan 37 and circulated to the heat radiating heat exchanger 32 again. I do. The cooling water of the heat exchanger 32 for heat radiation is circulated in the cooling water circulation pipe 35 by the pump P1 for cooling water, and is cooled in the heat radiator 36 by the cooling fan 37 of the heat radiator 36. Is sent to the vessel 32 to radiate the working gas.

The pump P1 for cooling water according to the present invention
Then, cooling water circulates in the pump body 38 and the bearing 44
Can always be immersed in the cooling water,
Can be prevented from burning.

For the cooling water, the pressure at the suction port 46 is set to Pi
Assuming that n, the pressure at the discharge port 48 is Pout, the pressure at the rear part of the pump body 38 is Pp, and the pressure within the cooling water reflux pipe 50 is Pb, the throttle 52 is provided.
In the case of the configuration shown in (a), Pout>Pp> Pb ≒ P
in, and backflow from the suction side pipe line 49 into the pump P1 through the opening 51 of the cooling water pump P1 is prevented. In the case of the configuration shown in FIG.
≒ Pb>Pp> Pin, and the backflow from the cooling water recirculation pipe 50 into the discharge side pipe 49 ′ is prevented. The rotor 40 of the motor 42 is always connected to the pump body 38.
Is pressed in the rearward direction, and the rotational shaft 41 is not displaced in the longitudinal direction, thereby enabling a stable rotation operation.

Although the embodiments of the present invention have been described based on the embodiments, the present invention is not limited to the above-described embodiments, and various modifications may be made within the scope of the technical matters described in the claims. It goes without saying that there are embodiments.

[0039]

As described above, the Stirling heat apparatus according to the present invention has a structure as described above, so that the bearing portion in the cooling water pump is constantly immersed in the cooling water, and the seizure of the bearing can be prevented. A stable and good radiator can be obtained.

[Brief description of the drawings]

FIG. 1 is an overall view for explaining an entire Stirling refrigerator as an application example of a pump according to the present invention.

FIG. 2 is a diagram illustrating a main body of a cooling water circulation pump for heat radiation used in the present invention.

FIG. 3 is a diagram for explaining an embodiment of a cooling water circulation pump for heat radiation according to the present invention.

FIG. 4 is a view showing another embodiment of the cooling water circulation pump for heat radiation according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Stirling refrigerator 1 2 Housing 3 Motor room 5 Crank room 6 Motor 14 Crankshaft 19 Compression cylinder block 20 Expansion cylinder block 21 Compression cylinder 22 Expansion block 26 Compression piston 28 Expansion piston 29 Oil seal 32 Heat dissipation heat exchanger 33 Regenerator 34 heat exchanger for cooling 35 cooling water circulation line 36 radiator (radiator) 37 cooling fan 38 pump body 38 'casing 42 motor 43 rotor can 44 bearing 45 impeller 46 suction port 47 impeller rotation chamber 48 discharge port 49 suction side pipe 49 '' Discharge side line 50 Cooling water reflux line 51 Opening 52 Restrictor 53 Cold head 54 Cooling fin 55 Accumulator

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Eiji Fukuda 2-5-5 Keihanhondori, Moriguchi-shi, Osaka F-term in Sanyo Electric Co., Ltd. (reference) 3J011 AA09 BA02 3J017 EA01 FA02 GA01

Claims (7)

[Claims] 1. A pump comprising: a pump body; and a liquid sending section located at a front end of the pump body and having a suction port, an impeller rotation chamber, and a discharge port, wherein the impeller is driven by a motor. The rotating shaft is supported by a submerged bearing in the pump body, connects a rear opening of the pump body with a suction side conduit, and circulates the liquid. A pump for providing a liquid recirculation conduit for causing the submerged bearing to be constantly immersed in the liquid during operation of the pump. 2. A pump comprising: a pump body; and a sending section located at a front end of the pump body and having a suction port, an impeller rotation chamber, and a discharge port, wherein the impeller is driven by a motor. The rotating shaft is supported by a submerged bearing in the pump body, connects an opening at a rear portion of the pump body to a discharge side pipeline, and circulates the liquid. A pump for providing a liquid recirculation conduit for causing the submerged bearing to be constantly immersed in the liquid during operation of the pump. 3. The pump according to claim 1, wherein a throttle is provided in the liquid reflux line. 4. The pump according to claim 1, wherein an accumulator is provided in the liquid reflux line. 5. The pump according to claim 1, wherein an on-off valve is connected to the liquid reflux line. 6. The cooling liquid circulated between the heat radiating heat exchanger and the radiator, and the pump is a cooling water pump for circulating the cooling water. The pump according to claim 1, 2, 3, 4, or 5. 7. The pump according to claim 1, wherein the heat radiating heat exchanger is a heat radiating heat exchanger for a working gas of a Stirling refrigerator.