Valves and valve actuation – Electrically actuated valve – Rotary electric actuator
Reexamination Certificate
1999-08-27
2001-07-03
Shaver, Kevin (Department: 3754)
Valves and valve actuation
Electrically actuated valve
Rotary electric actuator
C137S015010, C137S382000
Reexamination Certificate
active
06254059
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to an electrically operated flow control valve for controlling the flow of liquid, such as a refrigerant used in a refrigeration cycle of an air conditioner and the like, and particularly, to a flow control valve suited for controlling the flow of CO
2
refrigerant, and the like, used under high pressure.
DESCRIPTION OF THE RELATED ART
a priorly known electrically operated flow control valve to be used in a refrigeration cycle is shown in FIG.
12
. An electrically operated flow control valve
10
shown in the drawing comprises a first passage
22
and a second passage
23
communicated on a valve chamber
21
, a valve body
20
including a valve seat
24
formed to the side of the second passage
23
, a valve shaft
30
having a needle valve
31
mounted so as contact to and separate from the valve seat
24
, a seal case
42
having a lower cover
41
welded onto the upper portion of the valve body
20
and a cylindrical can
40
, and a motor
50
, such as a stepping motor and the like, having a stator portion
52
with a stator coil
51
mounted on the exterior of the seal case
42
and a rotor portion
53
placed inside said seal case
42
.
The rotor portion
53
comprises a magnet
54
surrounding the outer periphery thereof, and includes a sleeve
55
having a cylindrical bush
55
b
, on the inner periphery of which is formed a female screw portion
55
a
engaging to a male screw portion
25
a
of a fixing guide
25
vertically positioned inside the valve body
20
. The sleeve
55
is equipped with a limiting protrusion
56
for contacting a stopper
43
so as to limit the full-open position of the valve, and a limiting protrusion
57
for contacting a stopper
26
placed on the side of the valve body
20
so as to limit the full-close position of the valve. Further, the valve shaft
30
is connected to the upper end of the sleeve
55
by an E-ring
33
.
When the stator coil
51
of the stator portion
52
is excited by a pulse signal received from the outside, the rotor portion
53
is rotated for a predetermined amount based on the pulse signal. Such rotation moves the valve shaft
30
connected to the sleeve
55
of the rotor portion
53
in a vertical direction. Thereby, the space between the needle valve portion
31
and the valve seat
24
is adjusted, and the flow of the refrigerant traveling through said space may be controlled.
SUMMARY OF THE INVENTION
The electrically operated flow control valve
10
of the prior art explained above is designed to control the flow of refrigerant, such as flon, which is normally used under low pressure of approximately 30 kg/cm
2
. When using such conventional flow control valve
10
for controlling the flow of refrigerant, such as CO
2
, and the like, used as an alternate refrigerant, since such refrigerant is used under high pressure of approximately 150-250 kg/cm
2
, a crack may occur in the portion of the lower cover
41
welded and fixed to the upper portion of the valve body
20
. When such cracking occurs, a problem may occur in which the refrigerant, such as CO
2
, and the like, leaks to the exterior.
Therefore, the present invention is aimed at solving such problem, and the object of the invention is to provide an electrically operated flow control valve capable of performing the flow control of refrigerants, such as CO
2
and the like, used under high pressure, by forming a firm connection between the can and the valve body.
In order to achieve the above object, the electrically operated flow control valve according to the present invention comprises a valve body, a cylindrical can fixed to the upper portion of said valve body, and a motor including a rotor disposed within the interior of said can and a stator disposed on the exterior of said can, as the basic means. Further, the present invention includes means for fixing said can to said valve body including an outwardly extended flange portion formed on the opening of said can, a weld joint connecting said flange portion and said valve body, a screw portion formed on said valve body, and a box nut fit on said flange portion of said can and engaged with said screw portion of said valve body.
Further, means for fixing said can to said valve body includes a weld joint connecting said can and said valve body, a ring groove or plurality of concave portions formed on said valve body, and a caulking portion formed from the exterior of said can toward the inward direction so as to contact said ring groove or said concave portions of said valve body.
Even further, means for fixing said can to said valve body includes a screw portion formed to said valve body, a box nut being engaged to said screw portion, and a wedge-like ring member inserted between said valve body and said can so as to receive pressure from said box nut.
Moreover, means for fixing said can to said valve body includes a flange member welded to the opening of said can, and a plural number of bolts for fixing said flange member to said valve body.
Further, means for fixing said can to said valve body includes an outwardly extended step portion formed on the opening of said can, a flange member having a rim portion so as to interfit with said step portion of the can, and a plural number of bolts for fixing said flange member to said valve body.
Moreover, the electrically operated flow control valve according to another aspect of the present invention comprises a valve body, a cylindrical can fixed to the upper portion of said valve body, and a motor including a rotor disposed within interior of said can and a stator disposed on the exterior of said can, wherein a thickened portion is formed around an opening of said can, and said can is fixed to said valve body by said thickened portion being screwed onto said valve body and the contact portion between said can and said valve body being welded together.
According to the electrically operated flow control valve of the present invention having the above-mentioned structure, the can and the valve body are connected to each other through welding, and at the same time, the can and the valve body are fixed either through a box nut, or by caulking the can to the valve body. This enables the flow control valve to endure a long-term active pressure while maintaining the sealed state and preventing the can and the valve body from separating, thereby improving the reliability of the valve.
Moreover, according to another aspect of the invention, the fixture of the can and the valve body is performed by use of a wedge-shaped ring inserted therebetween, so the sealed state may be maintained and the reliability of the valve is improved even without forming a welded portion.
According to another aspect of the invention, the flange portion welded onto the opening of the can is further fixed to the valve body by bolts, so that a sealed state is created between the can and the valve body, and the can and the valve body is securely prevented from separating.
In yet another aspect of the invention, a step portion is formed about the opening of the can, and a flange portion being interfit to the step portion is fixed to the valve body through bolts. Even when the pressure inside the can is increased by refrigerants used under high pressure, such as CO
2
, the connection between the can and the valve body may be maintained firmly, and the sealed state may be retained.
REFERENCES:
patent: 1652038 (1927-12-01), Meyer
patent: 4584902 (1986-04-01), Fry
patent: 4763874 (1988-08-01), Ogawa
patent: 4930746 (1990-06-01), Reinickie et al.
patent: 5179977 (1993-01-01), Iwata et al.
patent: 5240227 (1993-08-01), Sich
patent: 5597009 (1997-01-01), Scherrer et al.
patent: 5680880 (1997-10-01), Miyake et al.
patent: 0191377 (1983-11-01), None
Inoue Yasushi
Kurosawa Naoya
Umezawa Hitoshi
Armstrong Westerman Hattori McLeland & Naughton LLP
Bonderer David
Fujikoki Corporation
Shaver Kevin
LandOfFree
Electrically operated flow control valve does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Electrically operated flow control valve, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Electrically operated flow control valve will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2561290