JP4116371B2 - Electric expansion valve - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electric expansion valve used in a refrigeration cycle of an air conditioner.
[0002]
[Prior art]
In a refrigeration cycle such as an air conditioner, when a refrigerant pressure higher than a predetermined level is generated on an intervening expansion valve due to output fluctuation of the compressor, the expansion valve may be damaged. Conventionally, the means for dealing with this high refrigerant pressure has not always been sufficient.
[0003]
[Problems to be solved by the invention]
An object of the present invention is to eliminate the above-mentioned problems of the prior art, and in an electric expansion valve used in a refrigerating cycle or the like of an air conditioner, when a refrigerant pressure higher than a predetermined level is generated, the refrigerant immediately below the predetermined pressure is generated. An object of the present invention is to provide an electric expansion valve that can be returned to pressure.
[0004]
[Means for Solving the Problems]
In order to solve the above problems, the present invention employs the following means. That is,
The electric expansion valve according to claim 1 is provided with two inlets and outlets in which fluid can flow in both forward and reverse directions in the block main body, and the valve is formed at the bottom of the valve chamber formed in the fluid passage between both the inlets and outlets. A seat mounting hole is formed, a valve seat is provided in the valve seat mounting hole, and a valve body that opens and closes the fluid passage by being separated from and contacting the valve seat by an electric valve body driving unit is provided. The valve seat is elastically pressed to the valve seat side by an upper spring provided on the body, and the valve seat is mounted on the valve seat that is formed at the upper end of the valve seat hole that penetrates the central portion of the valve seat. More than the diameter of the first fluid pressure receiving portion formed through a first fluid pressure receiving portion having an outer diameter that can be inserted into the hole and a flat surface located opposite to the inclined portion at the lower portion of the first fluid pressure receiving portion. A large second fluid pressure receiving portion, and the valve seat is provided below the valve seat. Are repression at a predetermined pressure to the valve seat mounting bore by the lower springs, when the fluid pressure above a predetermined pressure to the fluid passageway acts, for the fluid pressure in the first direction, the valve seat under the spring The valve body moves against the fluid pressure in the second direction, and the valve body moves against the upper spring to increase the flow rate. ]
According to a second aspect of the present invention, there is provided an electric expansion valve having two inlets and outlets in which fluid can flow in both forward and reverse directions in the block body, and a valve at the bottom of a valve chamber formed in a fluid passage between both the inlets and outlets. A valve seat that forms a seat mounting hole, provides a valve seat in the valve seat mounting hole, and opens and closes the fluid passage by being electrically connected to the valve seat by an electric valve body driving unit, and a bypass that bypasses between the inlet and outlet provided the sub-valve body and the hole, at a position facing the bypass hole, the valve body is repression at a predetermined pressure to the valve seat side by the spring on which is provided in the valve body, the sub-valve element is conical A first fluid pressure receiving portion that is inserted into the bypass hole in a shape, a shoulder portion provided at a lower portion of the first fluid pressure receiving portion, and a large diameter provided via a flat surface opposed to the lower portion of the shoulder portion second fluid pressure receiving portion Toka Rannahli consisting parts, sub-valve body is in the lower part of the sub-valve body When the lower spring provided is elastically pressed to the bypass hole with a predetermined pressure, and the fluid pressure higher than the predetermined pressure acts on the fluid passage , the sub-valve element is moved to the lower spring against the fluid pressure in the first direction. The valve body moves against the upper spring to rapidly increase the flow rate, and the valve body moves against the upper spring to increase the flow rate against the fluid pressure in the second direction.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
[Example 1]
Example 1 will be described below. 1 is a longitudinal cross-sectional view of the first embodiment, FIG. 2A is a plan view of the main part of the first embodiment, FIG. 2B is a cross-sectional view taken along the line DD of FIG. C) is a side view of the main part.
[0009]
The electric expansion valve according to the first embodiment includes a block main body 1 and a valve body driving unit 20 attached to the block main body 1. First, the block main body 1 will be described.
As shown in FIG. 1, the block main body 1 is composed of a block body made of an aluminum alloy or the like having a substantially L-shape in front view and a predetermined front and rear width, and a valve main body mounting hole 2 is formed on the upper surface 1a. In addition, a first inlet / outlet 3 is provided on the left side surface 1d, a first passage 4 is horizontally drilled in communication with the first inlet / outlet 3, and an end thereof forms a valve chamber 8. ing. Further, a strainer 5 for filtering the refrigerant is disposed in the first passage 4.
Further, a second entrance / exit 6 is formed in the lower surface 1b of the block body 1, and a second passage 7 is formed in communication with the second entrance / exit 6 toward the upper surface 1a. A portion 7 a is formed and communicates with the valve chamber 8 through the valve seat mounting hole 9.
[0010]
The valve main body 10 is attached to the valve main body attachment hole 2 via a sealing material, for example, a gasket (not shown). A screw cylinder 11 is provided at the center of the upper part. A male screw is formed on the outer periphery of the screw cylinder 11, and a pressure equalizing hole 33 is formed in the lower part thereof to communicate the gap in the screw cylinder 11 with the space above the valve body 10. Further, a stopper 12 is implanted in the valve body 10 adjacent to the screw cylinder 11.
[0011]
Next, the valve body drive part 20 attached to the upper part of the valve main body 10 is demonstrated. The valve body drive unit 20 includes a stator coil 22, a motor housing 21, a rotor 23, a sleeve 24, and the like. The stator coil 22 is wound around a bobbin on the outer surface of a can 29 that is integrally welded to the upper surface of the valve body 10. The rotor 23 and the sleeve 24 integral with the rotor 23 are disposed inside the can 29. A female screw is formed on the inner peripheral surface of the sleeve 24, and the female screw meshes with the male screw on the outer periphery of the screw cylinder 11.
The rotor 23 is pressed against the sleeve 24 from above by a flat spring 25, and the flat spring 25 is integrated with the sleeve 24 by a retaining ring 26. Further, a stopper 28 is provided at the lower portion of the sleeve 24 so as to face downward, and engages with the stopper 12 planted on the valve body 10 side.
[0012]
Further, a valve rod 30 integral with the valve body 34 is inserted into the hole at the center of the sleeve 24, and the upper portion of the valve rod 30 is rotatably fitted to the upper portion of the sleeve 24. Further, a collar 27 is provided at the upper end of the valve stem 30, and the valve stem 30 receiving a spring load downward with respect to the sleeve 24 is integrally formed. Further, in the hole at the center of the sleeve 24, it is between the ring-shaped spring retainer 32 ′ disposed on the inner wall at the upper end of the sleeve 24 and the ring-shaped spring retainer 32 disposed on the step portion of the valve stem 30. An upper spring 31 is interposed to press the valve rod 30 downward with a predetermined pressure. As a result, the upper spring 31 presses the valve body 34 against the sheet material 40 with the predetermined pressure.
[0013]
Next, the valve seat 40 will be described.
As shown in FIG. 2 in particular, the valve seat 40 is formed in a cylindrical shape as a whole, and a valve seat hole 40a is formed at the center thereof. The upper end portion of the valve seat 40 is formed with a first fluid pressure receiving portion 41 having an outer diameter that can be disposed in the valve seat mounting hole 9, and a lower portion thereof is larger than the diameter of the first fluid pressure receiving portion 41. The second fluid pressure receiving portion 42 is formed so that the second fluid pressure receiving portion 42 is in sliding contact with the inner surface of the small diameter portion 7a.
The valve seat 40 is elastically held in the direction of the valve seat mounting hole 9 by a lower spring 43. The lower spring 43 is supported by a lower spring presser 44 disposed in the second passage 7. A through hole 45 is formed in the center of the lower spring retainer 44.
[0014]
When the electric expansion valve is arranged in the refrigeration cycle with the above configuration, the following effects are obtained.
First, when the refrigerant flows in the direction from the first inlet / outlet 3 to the second inlet / outlet 6, the refrigerant passes through the first inlet / outlet 3, the first passage 4, the valve chamber 8, the second passage 7, and the like. The second inlet / outlet 6 will flow sequentially. During this time, the valve rod 30 is moved up to a certain position by energization of the valve body drive unit 20. Due to the upward movement of the valve rod 30, the valve element 34 arranged in the valve chamber 8 is separated from the valve seat 40 by a certain distance, so that the refrigerant expands through this gap, and then the second passage 7. And it flows through the 2nd entrance / exit 6 to an indoor heat exchanger.
[0015]
During this time, when the degree of expansion (in the refrigeration cycle, the strength of cooling) is changed, the rotor 23 and the sleeve 24 integrated therewith are rotated by applying a predetermined pulse current to the valve body drive unit 20, and the sleeve Since the internal thread 24 and the external thread on the outer periphery of the screw cylinder 11 mesh with each other, the sleeve 24 moves up and down with respect to the screw cylinder 11 while rotating. When the sleeve 24 moves up and down, the valve rod 30 is moved up and down to adjust the passage amount of the refrigerant.
During such operation, when the refrigerant pressure in the first passage 4 becomes higher than a predetermined pressure, the refrigerant pressure acts on the first fluid pressure receiving portion 41 constituting the bottom portion of the valve chamber 8, When the refrigerant pressure becomes larger than the elasticity value of the lower spring 43, the valve seat 40 moves downward against the lower spring 43.
[0016]
At this time, the refrigerant that has passed through the valve seat mounting hole 9 acts on the second fluid pressure receiving portion 42. However, the pressure receiving area is widened, so that the valve seat 40 is suddenly subjected to a large refrigerant pressure and rapidly decreases downward. Moving. As a result, troubles associated with abnormal refrigerant pressure are avoided. During this time, when the refrigerant pressure of the refrigerant flowing from the first inlet / outlet 3 returns to a predetermined value or less, the valve seat 40 returns to a position below the predetermined pressure as the refrigerant pressure decreases, and performs a predetermined expansion action. It will be.
[0017]
On the other hand, when the refrigerant flows from the second inlet / outlet 6 to the first inlet / outlet 3, the valve body 34 is set in its position, that is, the opening degree by the valve body driving unit 20 via the valve rod 30, and the opening degree In this case, the refrigerant flows.
During this time, when a refrigerant pressure higher than a predetermined value is generated in the refrigerant, the refrigerant pressure acts on the lower end portion of the valve body 34 from the valve seat hole 40a, and the valve body 34 rises against the upper spring 31 by the pressure. As a result, the refrigerant flows from the gap to the first inlet / outlet 3 side. During this time, if the pressure of the refrigerant from the second inlet / outlet 6 decreases, the valve element 34 is restored to the original position by the elastic force of the upper spring 31 and has a predetermined opening.
As described above, according to the first embodiment, in the reversible electric expansion valve, a relief action that operates quickly is applied to a refrigerant pressure higher than a predetermined value regardless of the direction of the refrigerant flow. As a result, a highly safe electric expansion valve can be obtained.
[0018]
[Example 2]
Next, Example 2 will be described.
3 is a longitudinal sectional view of the second embodiment, FIG. 4 (A) is a plan view of the main part of the second embodiment, FIG. 4 (B) is a sectional view taken along the line DD in FIG. 4 (A), and FIG. C) is a side view of the main part. In the second embodiment, the configuration of the valve body driving unit 20 and the configurations of the valve stem 30 and the valve body 34 are the same as those in the first embodiment, and therefore, the description thereof is omitted by attaching the same reference numerals to the drawings.
The electric expansion valve according to the second embodiment includes a block main body 1 ′ and a valve body drive unit 20 attached to the block main body 1 ′.
First, the block body 1 ′ will be described.
As shown in FIG. 3, the block body 1 ′ is composed of a block body made of an aluminum alloy or the like having a substantially L-shape in a front view and a predetermined front and rear width as in the first embodiment. A valve body mounting hole 2 is formed, and a first inlet / outlet 3 is provided on the left side surface 1d ′, and a first passage 4 ′ is horizontally drilled in communication with the first inlet / outlet 3, Its end forms a valve chamber 8. Further, a strainer 5 for filtering the refrigerant is disposed in the first passage 4 '.
Further, a second entrance / exit 6 is formed on the lower surface 1b ′ of the block main body 1 ′, and a second passage 7 ′ is formed in communication with the second entrance / exit 6 toward the upper surface 1a ′. Is formed with a small-diameter portion 7a 'and communicates with the valve chamber 8 through a valve seat mounting hole 9'.
[0019]
In the second embodiment, the valve seat 40 'is formed in a cylindrical shape, and a receiving portion for the valve body 34 is formed on the upper portion thereof. The valve seat 40 'is mounted in the valve seat mounting hole 9' and does not move relative to the block body 1 '.
Further, a bypass hole 51 is formed in the middle of the first passage 4 ′ of the block body 1 ′, and is formed until the control valve hole 52 having a circular cross-sectional shape communicates with the bypass hole 51 and reaches the lower surface 1b ′. A control valve auxiliary hole 57 is formed in the lateral direction from the middle of the control valve hole 52 to join the second passage 7 ', and the right end of the control valve auxiliary hole 57 is the right side of the block main body 1'. While opening in the surface 1 c ′, the opening is closed by a lid 56. The upper portion of the control valve hole 52 is a small diameter portion 52a.
[0020]
A fluid pressure control valve 50 is disposed in the control valve hole 52. As the fluid pressure control valve 50, a sub-valve element 53 is disposed at a position facing the bypass hole 51, and the sub-valve element 53 is elastically pressed upward by the lower spring 54, that is, in a direction to close the bypass hole 51. Has been. The lower part of the lower spring 54 is supported by a lower spring retainer 55, and the lower opening of the control valve hole 52 is closed by a lid 58.
The sub-valve body 53 is formed with a first fluid pressure receiving portion 53a that contacts the bypass hole 51 and a second fluid pressure receiving portion 53c having a large diameter portion, and a shoulder portion 53b is formed at an intermediate portion thereof.
[0021]
The operation of the second embodiment will be described. In the second embodiment, when the refrigerant flows from the first inlet / outlet 3 to the second inlet / outlet 6, the refrigerant is the first inlet / outlet 3, the first passage 4 ′, the valve chamber 8, and the valve seat hole 40 a ′. While passing through the second passage 7 'and the second inlet / outlet 6, the valve body drive unit 20 sets the position (opening) of the valve body 34 with respect to the valve seat 40' during this time, and a predetermined expansion action is performed. Is done.
[0022]
During this time, when the refrigerant pressure in the first passage 4 ′ becomes equal to or higher than a predetermined value, the first fluid pressure receiving portion 53 a in the bypass hole 51 is pressed downward by the pressure of the refrigerant, and the refrigerant pressure is further reduced to the shoulder portion 53 b and the second pressure. By acting on the fluid pressure receiving portion 53c, a bypass circuit is formed at once, and the high-pressure refrigerant flows out from the second inlet / outlet 6 through the bypass hole 51, the control valve hole 52, the control valve auxiliary hole 57, and the second passage 7 ′. To do.
Then, when the refrigerant pressure in the first passage 4 ′ is reduced, the bypass hole 51 is closed by the subvalve body 53, and the normal state, that is, the valve seat 8 ′ is passed through the valve seat 40 ′ to perform the expansion action. .
[0023]
Conversely, when the high-pressure refrigerant flows in the direction from the second inlet / outlet 6 to the first inlet / outlet 3, the refrigerant is throttled by the valve seat 40 ′ and the valve body 34, as in the first embodiment, and the first passage. It flows out from the 1st entrance / exit 3 via 4 '. During this time, when the refrigerant pressure in the second passage 7 ′ becomes equal to or higher than a predetermined value, the refrigerant pressure acts on the valve body 34, so the refrigerant pressure lifts the valve rod 30 upward, and the valve body The clearance between the valve 34 and the valve seat 40 'becomes large, and the refrigerant flows out rapidly. During this time, the sub valve body 53 is strongly pressed against the bypass hole 51, so that the bypass hole 51 is not "open".
[0024]
As described above, also in the second embodiment, the block main body 1 ′ is provided with the two inlets 3 and 6 that allow the refrigerant to flow in both forward and reverse directions, and is formed in the refrigerant passage between both the inlets and outlets 3 and 6. A valve seat mounting hole 9 ′ is formed at the bottom of the valve chamber 8, the valve seat 40 ′ is provided in the valve seat mounting hole 9 ′, and the valve seat 40 is driven by the electric valve body driving unit 20. A valve element 34 that opens and closes the fluid passage is opened and closed, and when a refrigerant pressure higher than a predetermined pressure is applied to the fluid passage, the load of the refrigerant pressure is applied regardless of whether the refrigerant flows in the forward or reverse direction. To increase the flow rate, that is, the bypass hole 51 is provided in communication with the first passage 4 ′, and the bypass hole 51 is attached to the refrigerant pressure higher than a predetermined pressure in the first direction. The fluid pressure control valve 50 allows the refrigerant to flow out quickly and below a predetermined value. It can be the refrigerant pressure.
[0025]
【The invention's effect】
According to the present invention, in the reversible electric expansion valve having the above-described configuration, an abnormal high pressure in the cycle is avoided by flowing a large amount of refrigerant with a relief function for a refrigerant pressure exceeding a predetermined value in any direction in the refrigerant flow. can do. And since the refrigerant | coolant of the fluid pressure was discharged rapidly, the function of a refrigerating cycle can be made still smoother.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a first embodiment according to the present invention.
FIG. 2 is a plan view (A) of a main part of the first embodiment, a cross-sectional view taken along a line DD in FIG. 2 (A), and a side view (C) of the main part.
FIG. 3 is a longitudinal sectional view of a second embodiment according to the present invention.
4 is a plan view (A) of a main part of a second embodiment, a cross-sectional view taken along the line DD of FIG. 4 (B), and a side view (C) of the main part.
[Explanation of symbols]
1, 1 '... Block body 1a, 1a' ... Upper surface 1b, 1b '... Lower surface 1c' ... Right side 1d, 1d '... Left side 2 ... Valve body mounting hole 3 ... No. 1 entrance 4, 4 '... first passage 5 ... strainer 6 ... second entrance 7, 7' ... second passage 7a, 7a '... small diameter portion 8 ..Valve chamber 9, 9 '... Valve seat mounting hole 10 ... Valve body 11 ... Screw cylinder 12 ... Stopper 20 ... Valve drive unit 21 ... Motor housing 22 ... Stator coil 23 ... Rotor 24 · · Sleeve 25 · · Flat spring 26 · · Retaining ring 27 · · Collar 28 · · Stopper 29 · · Can 30 · · Valve stem 31 · · Upper spring 32 · 32 '· · Spring retainer 33 · · Pressure equalizing hole 34 .. Valve body 40, 40 '... Valve seat 40a, 40a' ... Valve seat hole 41 ... First fluid pressure receiving part 42 ... Second Body pressure receiving portion 43 ... lower spring 44 .. under spring retainer 45 ... hole
46a, 46b ... Flat surface 50 ... Fluid pressure control valve 51 ... Bypass hole 52 ... Control valve hole 52a ... Small diameter part 53 ... Sub valve body 53a ... First fluid pressure receiving part 53b ... Shoulder part 53c ..Second fluid pressure receiving part 54..Lower spring 55..Lower spring retainer 56..Cover body 57..Control valve auxiliary hole 58..Cover body
59a, 59b ... Flat surface

Claims (2)

The block body is provided with two inlets / outlets through which fluid can flow in both forward and reverse directions, and a valve seat mounting hole is formed at the bottom of the valve chamber formed in the fluid passage between both the inlets and outlets. Provided with a valve seat in the hole, and provided with a valve body that opens and closes the fluid passage by being separated from the valve seat by an electric valve body drive unit,
The valve body is elastically pressed at a predetermined pressure on the valve seat side by an upper spring provided on the valve body,
The valve seat includes a valve seat hole penetrating through a central portion thereof, a first fluid pressure receiving portion having an outer diameter that can be inserted into the valve seat mounting hole formed at an upper end portion of the valve seat, and a first fluid pressure receiving portion. A second fluid pressure receiving portion larger than the diameter of the first fluid pressure receiving portion formed through a flat surface opposite to the inclined portion at the lower portion of the portion, and the valve seat is provided at the lower portion of the valve seat Is pressed down to the valve seat mounting hole with a predetermined pressure by the lower spring,
If the fluid pressure above a predetermined pressure to the fluid passage is applied, for the fluid pressure in the first direction, the valve seat causes increasing rapidly the flow rate moves against the lower spring, the second An electrical expansion valve, wherein the valve body moves against the upper spring to increase the flow rate against the fluid pressure in the direction. The block body is provided with two inlets / outlets through which fluid can flow in both forward and reverse directions, and a valve seat mounting hole is formed at the bottom of the valve chamber formed in the fluid passage between both the inlets and outlets. A valve seat is provided in the hole, and a valve body that opens and closes the fluid passage by being brought into contact with the valve seat by an electric valve body driving unit, a bypass hole that bypasses between the inlet and the outlet, and a position that faces the bypass hole. A valve body,
The valve body is elastically pressed at a predetermined pressure on the valve seat side by an upper spring provided on the valve body,
The sub-valve has a first fluid pressure receiving portion inserted into the bypass hole in a conical shape, a shoulder portion provided at a lower portion of the first fluid pressure receiving portion, and a flat surface positioned opposite to the lower portion of the shoulder portion second fluid pressure receiving portion Toka Rannahli consisting large diameter portion which is provided via a sub-valve body is repression at a predetermined pressure to the bypass hole by the lower spring provided in the lower portion of the sub-valve body,
When a fluid pressure higher than a predetermined pressure is applied to the fluid passage , the sub-valve element moves against the lower spring to rapidly increase the flow rate against the fluid pressure in the first direction, and the second An electrical expansion valve characterized in that the valve body moves against the upper spring to increase the flow rate against the fluid pressure in the direction of.

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