JPH10159976A - Bellows structure body and pump device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a part between both bellows as a heat insulating structure, and reduce a heat loss by heat conduction between the inside and outside of bellows by sealing and fixing both end parts of inside bellows and outside bellows, and holding a part between the outside bellows and the inside bellows in a vaccum condition or a condition close to a vacuum. SOLUTION: In a bellows structure body A, since a part between outside bellows 6 and inside bellows 7 is held in a vacuum or a condition close to this, a sufficient heat insulating effect is presented, and therefore, fluid flowing in the inside bellows 7 is hardly influenced by an outside air temperature. As a result, when this bellows structure body is used for a pump of the fluid, a temperature of this fluid can be always kept constant without being influenced by an external enenvironment. In the bellows structure body A, Since its constitutive part is completely sealed by stainless steel, liquid leakage is not caused, and it can endure even a very low temperature fluid, and therefore, pump efficiency can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bellows structure and a pump device used for transporting a fluid such as a liquid or a gas while maintaining a constant temperature.

[0002]

2. Description of the Related Art Conventionally, a fluid is accommodated in a single thin metal bellows, and the metal bellows is subjected to amplitude (expansion and contraction).
A pump device that generates a flow in the fluid by operating it, sucks fluid from the outside into the metal bellows through a suction valve, and discharges the fluid in the metal bellows to the outside through a discharge valve. Widely provided.

[0003]

However, in such a conventional pump device, since the bellows itself is formed of a single thin metal plate, a fluid or gas passing through the metal bellows, for example, The temperature of the refrigerant used in the freezing cycle of the freezer cannot be kept constant due to the outside air, that is, the outside air temperature is transmitted to the metal bellows to affect the temperature of the refrigerant flowing inside, thereby causing heat loss. There were problems such as a decrease in refrigeration efficiency.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems. By providing a bellows body with a heat insulating structure in which an outer bellows and an inner bellows are interposed through a gap, heat conduction between the inside and the outside is achieved. It is an object of the present invention to provide a bellows structure capable of greatly reducing heat loss due to the bellows.

Further, the present invention provides a pump device capable of sucking a fluid having a constant temperature from the outside by using the bellows structure, and discharging the internal fluid to the outside while maintaining the constant temperature. The purpose is to:

[0006]

According to a first aspect of the present invention, there is provided a bellows structure comprising an outer bellows and an inner bellows disposed inside the outer bellows. Further, both ends of the outer bellows are hermetically sealed and fixed so that a space between the outer bellows and the inner bellows is maintained in a vacuum state or a state close to a vacuum.

A bellows structure according to a second aspect of the present invention comprises an extendable bellows, a base plate for sealingly fixing one end of the bellows, and a sealing plate for closing the other end of the bellows. , An outer bellows and an inner bellows arranged inside the outer bellows.

A bellows structure according to a third aspect of the present invention is characterized in that the base plate is provided with a vacuum evacuation hole which communicates between the outer bellows and the inner bellows and has a stopper which is removably sealed. is there.

A pump device according to a fourth aspect of the present invention comprises a telescopic bellows, a base plate for fixing one end of the bellows, and a sealing plate for closing the other end of the bellows. It is composed of an outer bellows and an inner bellows arranged inside the outer bellows, and both ends of the inner bellows and the outer bellows are hermetically sealed to a base plate and a sealing plate, so that a gap between the outer bellows and the inner bellows is provided. A bellows structure maintained in a vacuum state or a state close to a vacuum, and a fluid passage formed in the base plate, wherein when the bellows structure is extended, an external fluid is sucked into the inner bellows and contracted. A valve body for discharging the fluid in the inner bellows to the outside during operation.

In the pump device according to the present invention, the bellows structure and the valve body are made of stainless steel.

According to a sixth aspect of the present invention, in the pump apparatus, the bellows structure alternately repeats the expansion and contraction operations in accordance with the movement of the eccentric cam driven by the motor. Things.

Further, in the pump device according to the present invention, the bellows structure is provided with a spring which constantly urges the bellows structure in the extending direction.

In the pump device according to the present invention, the fluid is a refrigerant used in a refrigeration cycle.

Further, the pump device according to the ninth aspect of the present invention is such that the base plate is provided with a vacuum evacuation hole which communicates between the outer bellows and the inner bellows and has a stopper which is removably sealed.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing a bellows structure of the present invention and a pump device having the bellows structure. In FIG. 1, reference numeral 1 denotes a stainless steel base plate, and the base plate has two passages as passages. The holes 2 and 3 are formed so as to penetrate, and one is used as a fluid suction passage and the other is used as a fluid discharge passage.

4 is disposed in a recess 5 formed on one side surface of the base plate 1, and the through holes 2, 3
A flap-shaped reed valve made of stainless steel is provided at each of the corresponding portions so as to be openable and closable. Are configured to be opened when the fluid is discharged. The details of the reed valve as the valve element 4 will be described later.

Reference numeral 6 denotes a stainless steel outer bellows as a metal bellows, and reference numeral 7 denotes a stainless steel inner bellows disposed inside the outer bellows 6 with a gap G therebetween. It is hermetically fixed to the other side surface of the base plate 1 by welding or the like so as to surround the holes 2 and 3.

Reference numeral 8 denotes a stainless steel sealing plate which is hermetically fixed to the other end of the outer bellows 6 and the inner bellows 7 by welding or the like, and a guide projection 9 is integrally provided at the center of the inner surface thereof. One end of a stainless steel spring 10 that constantly urges the bellows 6 and 7 in the extension direction is inserted into the guide projection 9 and is in contact with the inner surface of the sealing plate 8.

The other end of the spring 10 is fitted and supported in a recess 1a formed on the other side of the base plate 1. Thus, the spring 10 urges the sealing plate 8 in a direction opposite to the base plate 1 side.

Reference numeral 11 denotes an eccentric roller as an eccentric cam, which is attached to a drive shaft 13 of a motor 12, and the outer peripheral surface of the eccentric roller 11 is in contact with the outside of the sealing plate 8. Therefore, the rotation of the eccentric roller 11 causes the sealing plate 8 to repeatedly approach and separate from the base plate 1 with a predetermined stroke, and the inner and outer bellows 6 and 7 also expand and contract correspondingly.

Reference numerals 14 and 15 denote vacuum evacuation holes formed in the outer peripheral portion of the base plate 1 at right angles.
These inner ends communicate with each other and the thicker vacuum evacuation hole 14
A vacuum pull plug 17 is screwed into the outer end of the device through a sealing material 16. The outer end of the narrower vacuum evacuation hole 15 is open to a gap G held in a vacuum or substantially a vacuum (for example, -750 mmHg) between the outer bellows 6 and the inner bellows 7.

Next, the operation will be described. First, when the motor 12 is driven, the sealing plate 8 reciprocates in the axial direction of the base plate 1 by the eccentric rotation of the eccentric roller 11, and at the same time, a bellows structure A including the outer bellows 6 and the inner bellows 7 is formed. Telescopic operation.

Therefore, the sealing plate 8 is moved by the expansion and contraction movement.
Moves forward against the spring 10, the pressure of the fluid stored up to now in the inner bellows 7 increases, so that the fluid flows from the through hole 3 to the corresponding valve element 4
Is discharged to the outside through the reed valve.

Subsequently, the eccentric roller 11
When the sealing plate 8 moves backward due to the resilient force of the spring 10 due to the eccentric rotation of, the pressure of the fluid in the inner bellows 7 decreases, so that the fluid from the outside Is sucked into the inner bellows 7 through the reed valve.

The suction of the fluid into the inner bellows 7 and the discharge of the fluid from the inner bellows 7 by the expansion and contraction operation of the bellows structure A are repeated, so that the fluid can be continuously transported. it can.

FIG. 2 shows the pump device more specifically. Here, an outer bellows 6 and an inner bellows 7 of a bellows structure A are provided in a case 21 together with a sealing plate 8.

As shown in FIG. 3, the sealing plate 8 is guided along the inner peripheral wall of the case 21 to a ring-shaped support plate 22 attached by welding so as to protrude to the outer periphery of the sealing plate 8. A ring-shaped guide plate 23 having an L-shaped cross section is attached. A small gap H for allowing air to flow is provided between the outer periphery of the guide plate 23 and the inner peripheral wall of the case 21 in order to smooth the expansion and contraction of the bellows structure A.

Further, here, the eccentric roller 11 has a cylindrical support shaft 2 mounted and fixed on the outer periphery of the drive shaft 13 of the motor 12.
It is attached to five ends by fixing screws 26.

Reference numerals 27 and 28 denote a suction pipe and a discharge pipe for the fluid which communicate with the respective through holes 2 and 3 via the valve body 4.

As shown in FIGS. 4 (a) and 4 (b), the valve body 4 has flap-shaped reed valve bodies 34 on both sides of a partition base plate 33 having two through holes 31 and 32.
35, and these reed valve bodies 34, 35
And sealing members 36 and 37 made of Teflon or the like are provided on the seal members 36 and 37.
Small through holes 38 and 39 communicating with the first and second holes 32 and relatively large through holes 40 and 41 are formed.

Therefore, as shown in FIG. 4 (a), only one reed valve element 35 is opened at the time of suction of the fluid, and at the time of discharge, as shown in FIG. 4 (b).
Only 4 operates to open.

In the bellows structure A as described above, since the space between the outer bellows 6 and the inner bellows 7 is maintained in a vacuum or a state close thereto, a sufficient heat insulating effect is exhibited. The fluid flowing through is hardly affected by the outside air temperature.

As a result, when the above-mentioned fluid pump is used for the bellows structure, the temperature of the fluid can be kept constant without being affected by the external environment. This is particularly advantageous for transporting the refrigerant of the refrigeration cycle and for transporting other liquids and gases.

Further, since the bellows structure A has its components completely sealed with stainless steel, liquid leakage does not occur, and the bellows structure A withstands extremely low temperature fluids, so that the pump efficiency is improved.

Further, by coating Teflon on the reed valve bodies 34 and 35, the sealing performance of the valve body 4 against the base plate 1 and other mounting members is further improved.

The bellows structure according to the present invention comprises:
The present invention may be applied not only to a pump device but also to a metal bellows accumulator arranged in a fluid circuit for absorbing a pulsation of a fluid in a hydraulic device, a fuel system of an engine, or the like.

[0037]

As described above, according to the first aspect of the present invention, the outer bellows and the inner bellows disposed inside the outer bellows are provided, and both ends of the inner bellows and the outer bellows are hermetically fixed. Then, since the space between the outer bellows and the inner bellows is maintained in a vacuum state or a state close to a vacuum, the space between the outer bellows and the inner bellows becomes a heat insulating structure, and the inner bellows and the outer bellows are closed. Heat loss due to heat conduction can be greatly reduced.

According to the second aspect of the present invention, the bellows includes an extendable bellows, a base plate for fixing one end of the bellows, and a sealing plate for closing the other end of the bellows. And since it was composed of the inner bellows arranged inside this outer bellows, both ends of the outer bellows and the inner bellows were sealed and fixed,
The space between the outer bellows and the inner bellows can be reliably maintained in a vacuum state or a state close to a vacuum. The effect is obtained that heat loss due to heat conduction between the outside can be greatly reduced.

According to the third and ninth aspects of the present invention,
Since the base plate is provided with a vacuum evacuation hole having a stopper that communicates between the outer bellows and the inner bellows and that is removably sealed, a vacuum state or a state close to vacuum is provided between the outer bellows and the inner bellows. Can be easier.

According to the fourth aspect of the present invention, the bellows includes a telescopic bellows, a base plate for fixing one end of the bellows, and a sealing plate for closing the other end of the bellows. And inner bellows arranged inside the outer bellows, and both ends of the inner bellows and the outer bellows are hermetically sealed to a base plate and a sealing plate, and a vacuum is applied between the outer bellows and the inner bellows. It has a bellows structure maintained in a state or a state close to vacuum, and by a valve body,
When the bellows structure is extended from the fluid passage of the base plate, fluid from the outside is sucked into the inner bellows when the bellows structure is extended, and the fluid in the inner bellows is discharged to the outside when the bellows structure is contracted. By using this, it is possible to obtain an effect that a fluid having a constant temperature can be sucked in from the outside, and an internal fluid can be discharged to the outside while maintaining the constant temperature.

According to the fifth aspect of the present invention, since the bellows structure and the valve body are made of stainless steel, leakage of fluid from the valve body can be prevented, and pump efficiency can be improved.

According to the sixth aspect of the present invention, the bellows structure is configured to alternately extend and contract in accordance with the movement of the eccentric cam driven by the motor. Since it is completely sealed, the pump operation can be smoothly performed even if the bellows structure has a double structure.

According to the seventh aspect of the present invention, since the bellows structure is provided with a spring which constantly urges the bellows structure in the extending direction, the extending operation of the bellows structure can be speeded up and the pump speed can be increased. The effect that it can be obtained is obtained.

Further, according to the invention of claim 8, since the fluid is a refrigerant used in a refrigeration cycle, the refrigeration effect of the refrigerant can be further enhanced.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a pump device according to an embodiment of the present invention.

FIG. 2 is a sectional view showing details of a pump device in FIG. 1;

FIG. 3 is an enlarged sectional view showing the vicinity of a sealing plate in FIG. 2;

FIGS. 4A and 4B are cross-sectional views showing details of the valve body in FIGS. 1 and 2, and are shown in FIGS.

[Explanation of symbols]

 G Air gap A Bellows structure 1 Base plate 4 Valve 6 Outer bellows 7 Inner bellows 8 Sealing plate 10 Spring 11 Eccentric roller (Eccentric cam) 34, 35 Reed valve (Reed valve)

Claims (9)

[Claims] An outer bellows and an inner bellows disposed inside the outer bellows, and both ends of the inner bellows and the outer bellows are hermetically fixed,
A bellows structure wherein a space between the outer bellows and the inner bellows is maintained in a vacuum state or a state close to a vacuum. 2. A bellows, which comprises a telescopic bellows, a base plate for sealing and fixing one end of the bellows, and a sealing plate for closing the other end of the bellows, wherein the bellows is arranged inside the outer bellows and the outer bellows. The bellows structure according to claim 1, wherein the bellows structure is constituted by a formed inner bellows. 3. The bellows according to claim 2, wherein the base plate is provided with a vacuum evacuation hole which communicates between the outer bellows and the inner bellows and has a stopper which is removably sealed. Structure. 4. A bellows comprising: a telescopic bellows; a base plate for fixing one end of the bellows; and a sealing plate for closing the other end of the bellows. The bellows is disposed inside the outer bellows and the outer bellows. The inner bellows and the outer bellows have both ends
A bellows structure that is hermetically fixed to a base plate and a sealing plate and that maintains a vacuum state or a state close to a vacuum between the outer bellows and the inner bellows; and a bellows provided in a fluid passage formed in the base plate. A pump device, comprising: a valve body that draws fluid from the outside into the inner bellows when the structure is extended, and discharges the fluid inside the inner bellows to the outside when the structure is contracted. 5. The pump device according to claim 4, wherein the bellows structure and the valve body are made of stainless steel. 6. The pump device according to claim 4, wherein the bellows structure alternately repeats expansion and contraction in accordance with the movement of an eccentric cam driven by a motor. 7. The pump device according to claim 4, wherein the bellows structure is provided with a spring that constantly urges the bellows structure in an extending direction. 8. The pump device according to claim 4, wherein the fluid is a refrigerant used in a refrigeration cycle. 9. The pump device according to claim 4, wherein the base plate is provided with a vacuum evacuation hole that communicates between the outer bellows and the inner bellows and has a stopper that is removably sealed. .