Information
-
Patent Grant
-
6354509
-
Patent Number
6,354,509
-
Date Filed
Tuesday, November 7, 200023 years ago
-
Date Issued
Tuesday, March 12, 200222 years ago
-
Inventors
-
Original Assignees
-
Examiners
- Doerrler; William
- Ali; Mohammad M
Agents
- Rader, Fishman & Grauer, PLLC
-
CPC
-
US Classifications
Field of Search
US
- 062 225
- 062 527
- 236 92 B
- 236 92 R
-
International Classifications
-
Abstract
A thermal expansion valve 100 has a valve chamber in a valve body 110, and controls the flow rate of refrigerant from a condenser and a receiver, and the refrigerant travels to an evaporator through a passage 132. Refrigerant returning from the evaporator transmits the temperature of refrigerant to a heat sensing shaft connecting to a power element portion 36 while traveling through a passage 34. A cover 200 has a head portion 220 and a tapered portion 210, and is mounted to the top portion of the valve body 110. Tapered outer surfaces 212 of the tapered portion of the cover 200 and tapered surfaces 114 of the valve body 110 form approximately identical surfaces. A concave portion 221 of the head portion 220 covers the power element portion 36, and its peak portion forms a curved surface 222.
Description
FIELD OF THE INVENTION
This invention relates to a thermal expansion valve used in a refrigeration cycle.
DESCRIPTION OF THE RELATED ART
Generally, of the components forming the refrigeration cycle in an air conditioner for vehicles, the evaporator is placed inside the passenger room, and others such as the compressor and the like are placed inside the engine room. The refrigeration cycle is provided with a thermal expansion valve for controlling the amount of refrigerant entering the evaporator.
FIG. 26
is a vertical cross-sectional view showing the state where a box-type expansion valve conventionally used as an expansion valve is placed in the refrigeration cycle of the air conditioner used for a vehicle, and
FIG. 27
is a schematic perspective view of the same. In
FIG. 26
, an expansion valve
10
is formed of a prismatic valve body
30
made from aluminum and the like, a first passage
32
through which refrigerant travels from a condenser
5
via a receiver
6
to an evaporator
8
in a refrigeration cycle
11
, and a second passage
34
through which refrigerant travels from the evaporator
8
to a compressor
4
, both passages being formed on the valve body
30
and placed vertically apart from each other. Also, the expansion valve
10
includes an orifice
32
a
and a valve chamber
35
provided to the first passage
32
, a spherical valve means
32
b
provided to the upstream side of the passage
32
for controlling the amount of refrigerant traveling through the orifice
32
a
, and an adjust screw
39
for a spring
32
d
providing pressure to the valve means
32
b
in the direction toward the orifice
32
a
through a valve member
32
c
. The adjust screw
39
having a screw portion
39
f
is screwed retrievably to a mount hole
30
a
connecting to the valve chamber
35
of the first passage
32
from the lower end surface of the valve body
30
, and an O-ring
39
g
is mounted to the adjust screw
39
so as to secure airtightness of the valve body
30
. The opening of the valve means
32
d
to the orifice
32
a
is adjusted by the adjust screw
39
and the pressure spring
32
d.
Reference number
321
is an entrance port where refrigerant exiting the receiver
6
and traveling toward the evaporator
8
enters. The entrance port
321
is connected to the valve chamber
35
, and reference number
322
is an exit port of the refrigerant flowing into the evaporator
8
. Also, reference number
50
of
FIG. 27
shows bolt holes for mounting the expansion valve, and the lower portion of the valve body
30
is thinned. A small-diameter aperture
37
for opening and closing the orifice
32
a
by providing driving force to the valve means
32
b
corresponding to the exit temperature of the evaporator
8
, and an aperture
38
having a larger diameter than the aperture
37
are provided to the valve body
30
coaxial to the orifice
32
a
. A screw hole
361
for fixing the power element portion
36
as a heat sensing portion is provided to the upper end of the valve body
30
.
The power element portion
36
constitutes a diaphragm
36
a
made of stainless steel and the like, and an upper pressure working chamber
36
b
and a lower pressure working chamber
36
c
formed coherent to each other by welding while interposing the diaphragm
36
a
, forming two airtight heat sensing chambers above and below the diaphragm
36
a
. The power element portion
36
is equipped with an upper lid
36
d
and a lower lid
36
h
made of stainless steel and the like, and a plug body
36
k
for enclosing predetermined refrigerant acting as a diaphragm driving fluid to the upper pressure working chamber
36
b
, and the lower lid
36
h
is screwed into a screw hole
361
through a packing
40
. The lower pressure working chamber
36
c
is connected to the second passage
34
through an equalizing hole
36
e
formed concentric with the center line of the orifice
32
a
. Refrigerant from the evaporator
8
travels through the second passage
34
, and the passage
34
becomes the passage for vapor refrigerant, and the pressure of the refrigerant is loaded to the lower pressure working chamber
36
c
through the pressure equalizing hole
36
e
. Reference number
342
is an entrance port where refrigerant exiting the evaporator
8
enters, and
341
is an exit port where refrigerant discharged to the compressor
4
exits.
Also, a peak portion
312
formed in a large-diameter saucer which comes into contact with the central portion of the lower surface of the diaphragm
36
a
is provided inside the lower pressure working chamber
36
c
. The power element portion
36
is further comprised of a heat sensing shaft
36
f
made of aluminum which pierces through the second passage
34
and is arranged slidably inside the large-diameter aperture
38
to transmit the temperature at the refrigerant exit of the evaporator
8
to the lower pressure working chamber
36
c
and which provides driving force by sliding inside the large-diameter aperture
38
corresponding to the displacement of the diaphragm
36
a
based on the difference in pressure between the upper pressure working chamber
36
b
and the lower pressure working chamber
36
c
, and a working shaft
37
f
made of stainless steel and having a smaller diameter than the heat sensing shaft
36
f
which is arranged slidably inside the small-diameter aperture
37
to provide pressure to the valve means
32
b
resisting to the elastic force of the spring means
32
d
corresponding to the displacement of the heat sensing shaft
36
f
. The upper end portion of the heat sensing shaft
36
f
is composed from a peak portion
312
as a receiving portion of the diaphragm
36
a
and a large-diameter portion
314
sliding inside the lower pressure working chamber
36
c
, and the lower end portion of the heat sensing shaft
36
f
comes into contact with the upper end portion of the working shaft
37
f
, the lower end portion of the working shaft
37
f
comes into contact with the valve means
32
b
, so that the heat sensing shaft
36
f
and the working shaft
37
f
constitute altogether the valve means driving shaft
318
. The peak portion
312
and the large-diameter portion
314
may be formed as one member.
That is, the valve means driving shaft
318
extending from the lower surface of the diaphragm
36
a
to the orifice
32
a
of the first passage
32
is concentrically arranged in the equalizing hole
36
e
. The portion
37
e
of the working shaft
37
f
having in a diameter smaller than the inner diameter of the orifice
32
a
pierces through the orifice
32
a
, and the refrigerant passes inside the orifice
32
a
. Also, an O-ring
36
g
is provided to the heat sensing shaft
36
f
in order to secure airtightness of the first passage
32
and the second passage
34
.
A known diaphragm driving fluid is filled inside the upper pressure working chamber
36
b
of the pressure working housing
36
d
, and the heat of the refrigerant at the refrigerant exit of the evaporator
8
traveling inside the second passage
34
is transmitted to the diaphragm driving fluid through the diaphragm
36
a
and the valve means driving shaft
318
exposed to the second passage
34
or the equalizing hole
36
e
connected to the second passage
34
.
The diaphragm driving liquid inside the upper pressure working chamber
36
b
turns into gas corresponding to the above-mentioned transmitted heat, and loads pressure to the upper surface of the diaphragm
36
a
. The diaphragm
36
a
is displaced vertically by the difference in the above-mentioned pressure of the diaphragm driving gas loaded to the upper surface and the pressure loaded to the lower side of the diaphragm
36
a.
The vertical displacement of the central portion of the diaphragm
36
a
is transmitted to the valve means
32
b
through the valve means driving shaft, and moves the valve means
32
b
closer to or away from the valve seat of the orifice
32
a
. As a result, the flow rate of the refrigerant is controlled.
Namely, the temperature of the low-pressure vapor refrigerant at the exit side of the evaporator
8
, that is, refrigerant exiting the evaporator, is transmitted to the upper pressure working chamber
36
b
, so that the pressure within the upper pressure working chamber
36
b
changes corresponding to the transmitted temperature, and the exit temperature of the evaporator
8
rises. When the heat load of the evaporator increases, the pressure within the upper pressure working chamber
86
b
increases, and the heat sensing shaft
36
f
, that is the valve means driving shaft, is driven downward moving the valve body
32
b
downwards, so that the opening of the orifice
32
a
increases. With such movement, the supply of refrigerant to the evaporator
8
increases, and lowers the temperature of the evaporator
8
. On the contrary, when the temperature of the refrigerant exiting the evaporator
8
drops, that is, when the heat load of the evaporator decreases, the valve means
32
b
is driven in the opposite direction, decreasing the opening of the orifice
32
a
, decreasing the supply of the refrigerant to the evaporator, so that the temperature of the evaporator
8
rises.
In such conventional thermal expansion valve, the heat sensing shaft
36
f
is a member having relatively large diameter, and such member and the working shaft constitute the valve means driving shaft. However, there is a conventional thermal expansion valve constituting the above-mentioned valve means driving shaft with a rod member, and such conventional thermal expansion valve
10
′ using the rod member is shown in FIG.
28
. The operation of the expansion valve shown in
FIG. 28
is the same as the expansion valve shown in
FIG. 26
or
27
, and the same reference numbers with
FIG. 26
or
27
indicate the same or equal portions.
A heat sensing portion
318
having a heat sensing mechanism operates as the heat sensing shaft
361
f
, comprising a large-diameter stopper
312
to the surface of which the diaphragm
36
a
contacts and acts as a receiving portion of the diaphragm
36
a
, a large-diameter portion
314
having one end surface adjoining the rear surface of the stopper
312
and having the central portion of the other end constituted as a projection
315
which is inserted slidably inside the lower pressure working chamber
36
c
, and a rodmember
316
of continuous integral composition with one end surface of which embedded to the interior of the projection
315
of the large-diameter portion
314
and the other end connected to the valve means
32
b
through a portion
371
corresponding to the working shaft. The heat sensing shaft
361
f
constituting the rod member
316
is exposed inside the second passage and the heat from the refrigerant vapor is transmitted thereto.
The rod member
361
which is a heat sensing shaft
361
f
is driven to move back and forth across the passage
34
corresponding to the displacement of the diaphragm
36
a
of the power element portion
36
, so that a clearance connecting the passage
32
and the passage
34
is formed along the rod portion
316
. In order to prevent formation of such clearance, an O-ring
42
fitted tightly to the outer circumference of the rod portion
316
is placed inside the large-diameter aperture
38
′ so that the O-ring exists between the passages. Moreover, in order to prevent the O-ring
42
from moving by the force operating in the longitudinal direction (the direction towards the power element portion
36
) provided by the coil spring
32
d
and the refrigerant pressure of the passage
321
, a push nut
41
as a self-locking nut is mounted to the rod portion
316
, positioned inside the large-diameter aperture
38
′ and contacting the O-ring
42
.
Such positioning and supporting structure of the conventional thermal expansion valve has been variously proposed. That is, a composition where an opening is provided on the division separating the engine room and the passenger room, and placing the thermal expansion valve to the passenger room side of the opening, connecting the refrigerant piping providing the refrigerant to the evaporator to the thermal expansion valve through a block-like connector, and supporting the above-mentioned connector through a packing material to the above-mentioned opening (for example, gazette of Japanese Patent Laid-Open 223427/95 and Japanese Utility Model Laid-Open 37729/95) has been proposed.
Also, a structure where the thermal expansion valve itself is supported to the opening through the packing material (for example, refer to the gazette of Japanese Patent Laid-Open 215047/95) has been proposed.
SUMMARY OF THE INVENTION
However, in such a supporting structure of the thermal expansion valve mentioned above, it is uneconomical in view of component cost and assembly cost to use the connector and the packing. Also, in the case where the thermal expansion valve is supported directly through the packing material, there is a problem that a clearance may be formed between the inner wall of said opening and the thermal expansion valve resulting in insufficient sealing. Moreover, in a conventional thermal expansion valve, the shape for supporting the thermal expansion valve of the air conditioner of an automobile to the opening of said division has never been considered. That is, the upper lid constituting the power element portion of the thermal expansion valve is formed as a dome provided with a cork body projecting from the wall portion of the upper lid so that ability to fit tightly with said inner wall of the opening becomes a problem, and the outer shape of the power element portion has not been considered.
Therefore, the present invention aims at providing a thermal expansion valve that could be tightly fixed to the opening provided to the division dividing the engine room and the passenger room, providing a secure seal.
In order to achieve the above-mentioned object, the thermal expansion valve of the present invention is comprised of a valve body, a power element portion provided to the upper end portion of said valve body which drives a valve means according to the displacement of a diaphragm, and an adjust screw provided to the lower end portion of said valve body which adjusts the pressurizing force of a spring controlling the valve opening of said valve means, wherein said power element portion is provided with a cover embracing the same, and the lower portion of said valve body is formed as a tapered surface.
Also, the thermal expansion valve of the present invention is comprised of a valve body equipped with a first passage through which refrigerant entering an evaporator travels and a second passage through which refrigerant exiting from said evaporator travels, the opening of a valve being controlled both by a valve means arranged opposing an orifice formed partway of said first passage and being biased toward the valve closing direction with a spring, and by a power element operated by sensing the temperature of said refrigerant traveling through said second passage and forcing said valve means toward the valve opening direction through a rod, wherein said power element is provided with a cover embracing the same, and the lower portion of said valve body provided with said spring is formed as a tapered surface.
Moreover, as a preferable embodiment of the thermal expansion valve of the present invention, the cover includes an interior formed with a concave portion and an exterior formed with curvature surfaces and tapered surfaces continuing therefrom, said concave portion storing the power element therein, and said tapered surfaces being substantially continued from the tapered surfaces of said valve body.
Further, as an embodiment of the thermal expansion valve of the present invention, the tapered surfaces of said valve body are formed from substantially the middle of the total height of said valve body.
Also, as an embodiment of the thermal expansion valve of the present invention, the valve body is formed to have an outer shape comprising mutually parallel surfaces starting from the upper surface provided with said power element portion and extended to approximately the middle of the total height of said valve body, and tapered surfaces continued therefrom which is tapered toward a bottom surface provided with an adjust screw.
According to the present invention being formed as explained above, the valve body is formed with parallel surfaces and tapered surfaces, enabling the valve body to fit tightly to the above-mentioned division wall, and improving the fixing capability.
Moreover, it could change the outer shape of the power element portion with the cover provided to the power element portion, and the fitting with the opening of the above-mentioned division wall is improved, and also the sealing ability is improved.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is a front view of the thermal expansion valve of the present invention;
FIG. 2
is a left side view of the thermal expansion valve of the present invention;
FIG. 3
is a right side view of the thermal expansion valve of the present invention;
FIG. 4
is a rear view of the thermal expansion valve of the present invention;
FIG. 5
is a top view of the thermal expansion valve of the present invention;
FIG. 6
is a bottom view of the thermal expansion valve of the present invention;
FIG. 7
is a front view of the thermal expansion valve with a cover;
FIG. 8
is a left side view of the thermal expansion valve with a cover;
FIG. 9
is a right side view of the thermal expansion valve with a cover;
FIG. 10
is a rear view of the thermal expansion valve with a cover;
FIG. 11
is a top view of the thermal expansion valve with a cover;
FIG. 12
is a bottom view of the thermal expansion valve with a cover;
FIG. 13
is a perspective view of the cover of the thermal expansion valve;
FIG. 14
is a side view showing the mounted state of the thermal expansion valve of the present invention;
FIG. 15
is a front view showing the mounted state of the thermal expansion valve of the present invention;
FIG. 16
is a front view of the thermal expansion valve of another embodiment of the present invention.;
FIG. 17
is a left side view of the thermal expansion valve of another embodiment of the present invention;
FIG. 18
is a right side view of the thermal expansion valve of another embodiment of the present invention;
FIG. 19
is a rear view of the thermal expansion valve of another embodiment of the present invention;
FIG. 20
is a top view of the thermal expansion valve of another embodiment of the present invention;
FIG. 21
is a bottom view of the thermal expansion valve of another embodiment of the present invention;
FIG. 22
is a perspective view of the cover of the thermal expansion valve;
FIG. 23
is a perspective view of the cover of the thermal expansion valve;
FIG. 24
is a side view showing the mounted state of the conventional thermal expansion valve;
FIG. 25
is a front view showing the mounted state of the conventional thermal expansion valve;
FIG. 26
is a longitudinal cross-sectional view of the conventional thermal expansion valve;
FIG. 27
is a schematic perspective view of another example of the conventional thermal expansion valve; and
FIG. 28
is a cross-sectional view of another example of the conventional thermal expansion valve.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
FIGS. 1 through 6
are drawings indicating one embodiment of the thermal expansion valve of the present invention, in which
FIG. 1
is a front view,
FIG. 2
is a left side view,
FIG. 3
is a right side view,
FIG. 4
is a rear view,
FIG. 5
is a top view, and
FIG. 6
is a bottom view.
The present invention provides the identical function as the conventional thermal expansion valve, and differs from the conventional thermal expansion valve only in the outer shape of the valve body. Therefore, the same reference numbers will be provided to the identical portions, and explanations on portions explained in the explanation of conventional valve are omitted.
The thermal expansion valve shown as a whole by reference number
100
has a valve body
110
made from aluminum alloy and the like. A power element portion
36
explained above is mounted to the peak portion of the valve body
110
, and the diaphragm inside the power element portion
36
operates a heat sensing shaft
361
f.
To one side near a bottom
116
of the valve body
110
is provided an entrance port
321
of a first passage
32
of the refrigerant supplied through a condenser and a receiver. The refrigerant thus introduced travels to an evaporator from an exit port
322
provided to the other side of the valve body through an orifice, the opening of which is adjusted by the heat sensing shaft
361
f.
The refrigerant exiting the evaporator travels through a second passage
34
provided to a power element portion
36
side of the valve body
110
. During the course, the temperature of the refrigerant is transmitted to the diaphragm through the heat sensing shaft
361
f.
The valve body
110
is provided with two perforation holes
50
in parallel to the axis of the second passage
34
. The perforation holes are used to pierce rods and the like to fasten the body to other members. Also, to the other side of the valve body
110
, a screw hole
152
is provided with a bottom in parallel to the perforation hole
50
, and a screwing bolt and the like is screwed thereto.
Sides
112
in parallel to the axis of a refrigerant passage
140
of the valve body
110
are construed of surfaces in parallel with each other from the top surface mounted with the power element portion
36
towards the bottom surface
116
until approximately the middle of the total height of the valve body
110
. From the middle of the body to the bottom surface
116
, the sides are formed as tapered surfaces
114
continuing from the parallel surfaces.
To the bottom surface
116
of the valve body
110
is mounted a nut member
39
for sealing the valve chamber explained before.
With the thermal expansion valve of the present invention, the valve body is comprised of parallel surfaces and tapered surfaces continuing from the parallel surfaces, so that it is easily fitted tightly to the division mentioned above, and the mounting ability is improved.
Next, an embodiment of the present invention where the thermal expansion valve of the present invention is mounted to said division will be explained.
FIG. 7
is a front view of the thermal expansion valve indicating the state where the cover is mounted to the outer side of the valve body of the thermal expansion valve shown in the embodiment of
FIGS. 1 through 6
,
FIG. 8
is a left side view,
FIG. 9
is a right side view,
FIG. 10
is a rear view,
FIG. 11
is a top view, and
FIG. 12
is a bottom view, each corresponding to
FIGS. 1 through 6
.
A cover shown as a whole by reference number
200
in the figure is formed from plastic resin and the like.
The cover
200
is provided with a head portion
220
having a concave portion
221
formed therein for storing the power element portion
36
, and a tapered portion
210
covering the outer side of the parallel sides of the thermal expansion valve
110
. The concave portion
221
stores the power element portion
36
, and contacts the outer peripheral of the power element portion
36
. Therefore, with the cover
200
, the outer shape of the power element portion
36
is adjusted. Outer sides
212
of the tapered portion
210
are formed as tapered surfaces forming approximately identical planes with the tapered surfaces
114
of the valve body
110
of the thermal expansion valve. Inner sides
214
of the tapered portion
210
are embedded to the parallel surface of the valve body
110
.
Outer surfaces
222
of the head portion
220
of the cover
200
are composed of curved surfaces.
Therefore, the thermal expansion valve mounted with the cover
200
has the side shape as is indicated in
FIGS. 8 and 9
.
Also, end surface
224
of the head portion
220
as seen from the front projects from the expansion valve body, and covers the entire power element portion
36
. The end surface
224
contacts with the expansion valve body with surface
226
orthogonal to the end surface
224
. As seen from above, the thermal expansion valve of the present invention is construed so as to have an outer shape formed from outer surfaces of the curved surfaces and the tapered surfaces, and the fitting of the thermal expansion valve and the mounting portion is improved.
FIG. 13
is a cross-sectional view of the cover
200
. The cover
200
is, for example divided into two parts, and is mounted to the thermal expansion valve. The divided surfaces are fixed with proper methods such as adhesive or fastener and the like. With the cover
200
, the power element is inserted to its concave portion and the outer peripheral of the power element is contacted thereto, so the sealing ability of the cover and the thermal expansion valve is improved, and also the mounting ability is improved.
FIG. 14
is a side view showing the condition where the thermal expansion valve of the present invention is mounted, for example, to an opening
501
formed at a division
500
dividing the engine room and the passenger room of an automobile, and
FIG. 15
is a front view.
The thermal expansion valve
100
with the cover
200
is held to the opening
501
which is the mounting portion formed to the division
500
made from metal board through a seal member
510
which is a packing member. Pipings
600
,
610
of the refrigerant are connected to the body of the thermal expansion valve with brackets
620
.
The front shape of the thermal expansion valve mounted with the cover
200
has a shape substantially covered with the tapered surfaces and the curved surfaces, so that fitting of the seal member
510
to the opening which is a mounting portion is improved, and the opening is sealed effectively.
Therefore, the engine room and the passenger room are sealed completely.
The above explanations were given regarding cases where the cover
400
is divided and mounted to the thermal expansion valve
100
. However, the present invention is not limited to such case, and could be applied to cases where the cover formed as a single body from plastic resin and the like is mounted to the thermal expansion valve.
FIGS. 16 through 23
show another embodiment of the present invention for such case, wherein the composition of the thermal expansion valve is the same as that shown in
FIGS. 1 through 6
, and so identical portions are provided with identical reference numbers and explanations thereof are omitted.
That is,
FIG. 16
is a front view of the thermal expansion valve showing the embodiment where the cover is mounted to the thermal expansion valve
100
,
FIG. 17
is a left side view,
FIG. 18
is a right side view,
FIG. 19
is a rear view,
FIG. 20
is a top view,
FIG. 21
is a bottom view,
FIG. 22
is a perspective view of the cover, and
FIG. 23
is a perspective view of the cover observed from the direction of arrow R in FIG.
22
.
In the figures, the cover indicated as a whole by reference number
400
is formed as a single body from plastic resin and the like.
A body
410
of the cover
400
has double side portions
412
and a head portion
422
, wherein the outer surface of the double side portions
412
are formed as tapered surface and the inner surfaces thereof are formed as plane surfaces
414
contacting the body of the thermal expansion valve
100
. The outer surface of the head portion
422
is formed as a curved surface, and concave portions
424
,
426
for storing the power element portion
36
of the thermal expansion valve are formed to the interior thereof. The power element portion
36
is inserted along the concave portions
424
and
426
, and the cover
400
is mounted to the thermal expansion valve
100
.
The depth size of the concave portions
424
and
426
are selected considering the position for storing the power element portion
36
when the cover
400
is mounted over the power element portion
36
.
A plurality of projecting portions
416
is formed at the rear end of the inner surface
414
of the double side portion
412
of the cover body
410
. When the cover
400
is mounted to the thermal expansion valve
100
, the expansion valve body
110
is stopped against the projecting portions
416
and is positioned thereto.
A plurality of arcuate notches
418
is formed to the lower end of the projecting portion
416
. The notches
418
are provided to avoid the interference of the bolt holes
50
for mounting provided to the thermal expansion valve body
110
.
Moreover, in the cover
400
shown in
FIGS. 22 and 23
, projecting portion of the end side
224
formed in the cover
200
of
FIG. 13
is omitted, and one portion of the power element portion
36
, as is shown in
FIG. 16
, is exposed from the concave portion
426
.
FIG. 24
is a side view showing the state where the thermal expansion valve
100
equipped with the cover
400
is mounted, for example, to an opening formed at a division
500
dividing the engine room and the passenger room of an automobile, and
FIG. 25
is a front view thereof. The composition is the same as that explained for
FIGS. 14 and 15
, therefore identical portions are given identical reference numbers and explanations thereof are omitted.
As seen from above, the present invention enables to adjust the shape of the outer peripheral of the power element portion by covering the thermal expansion valve used in the refrigeration cycle for a car air conditioner and the like with a cover. Therefore, the present invention provides a thermal expansion valve having secure and good seal ability when fixing the thermal expansion valve to the division between the engine room and the passenger room of an automobile and the like.
Claims
- 1. A thermal expansion valve, comprising:a valve body, a lower portion of which has a tapered surface; a power element portion provided to the upper end portion of said valve body which drives a valve means according to the displacement of a diaphragm; an adjust screw, provided to the lower end portion of said valve body, which adjusts the pressurizing force of a spring controlling the valve opening of said valve means; and a cover, embracing the power element portion, and having an exterior formed with a plurality of tapered surfaces.
- 2. A thermal expansion valve, comprising:a valve body, equipped with a first passage through which refrigerant entering an evaporator travels and a second passage through which refrigerant exiting said evaporator travels, and having a lower portion which has a tapered surface; a valve, arranged opposing an orifice formed partway of said first passage and being biased toward a closed direction with a spring; a power element that controls the opening of the valve, operated by sensing the temperature of said refrigerant traveling through said second passage and forcing said valve toward an open direction through a rod; and a cover, embracing the power element portion, and having an exterior formed with a plurality of tapered surfaces.
- 3. A thermal expansion valve according to claim 1 or 2, wherein said cover further includes an interior formed with a concave portion, and said exterior is further formed with a plurality of curvature surfaces with said plurality of tapered surfaces continue therefrom, said concave portion storing said power element therein, and said tapered surfaces being substantially continued from the tapered surfaces of said valve body.
- 4. A thermal expansion valve according to claim 3, wherein said tapered surfaces of said valve body are formed from substantially the middle of the total height of said valve body.
- 5. A thermal expansion valve according to claim 1 or 2, wherein said valve body is formed to have an outer shape comprising mutually parallel surfaces starting from the upper surface provided with said power element portion and extended to approximately the middle of the total height of said valve body, and tapered surfaces continued therefrom which is tapered toward a bottom surface provided with an adjust screw.
- 6. A thermal expansion valve according to claim 1 or 2, wherein said cover is formed as a single body using plastic material.
- 7. A thermal expansion valve according to claim 1 or 2, wherein said cover is formed from two parts using plastic material.
- 8. A cover for a thermal expansion valve, which comprises:a concave interior portion that embraces a power element of said thermal expansion valve; and an exterior portion formed with a plurality of tapered surfaces.
- 9. A cover according to claim 8, wherein said plurality of tapered surfaces are substantially continued from a tapered surface of a lower portion of a valve body of said thermal expansion valve.
- 10. A cover according to claim 8, wherein said cover is formed as a single body using plastic material.
- 11. A cover according to claim 8, wherein said cover is formed from two parts using plastic material.
Priority Claims (2)
Number |
Date |
Country |
Kind |
11-319892 |
Nov 1999 |
JP |
|
11-350701 |
Dec 1999 |
JP |
|
US Referenced Citations (3)
Number |
Name |
Date |
Kind |
4342421 |
Widdowson |
Aug 1982 |
A |
4984735 |
Glennon et al. |
Jan 1991 |
A |
D415564 |
Sendo et al. |
Oct 1999 |
S |