Temperature responsive valve

A temperature responsive valve includes a bimetal disk which snaps in response to changes in temperature, a rod moved by the snapping action of the bimetal disk, a valve member in association with movement of the rod to thereby control the flow of fluid, and an adjustment member threaded through a body to properly adjust the range in movement of the valve member, the adjustment member being secured to the body after adjusting operation of the range of movement of the valve member.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to a temperature responsive valve, and more 
particularly to a temperature responsive valve which controls flow of 
fluid in association with the snapping action of a bimetal disk in 
response to changes in temperature. 
2. Description of the Prior Art 
Conventionally, a temperature responsive valve has been proposed for use in 
an emission control system of vehicles which includes a bimetal disk which 
snaps in response to changes in temperature, a rod moved by the snapping 
action of the bimetal disk, and a valve member in association with 
movement of the rod to thereby control the flow of fluid. Such temperature 
responsive valve further includes an adjustment member which is, for 
example adjustably threaded through a body to thereby adjust the range of 
movement of the valve member. Thus, quantity of flow of fluid may be 
properly adjusted. In such prior temperature responsive valve, however, 
the relative position between the body and the adjustment member is 
changed due to loosening of the threaded portions therebetween caused by 
vibration of the vehicle and the like. In order to overcome this 
disadvantage, the use of a locking plate has been proposed to prevent 
relative rotation between the body and the adjustment member. Thus in the 
prior temperature responsive valve, the number of parts is necessarily 
increased and thus results in high cost of manufacturing. 
SUMMARY OF THE INVENTION 
It is therefore an object of the present invention to provide an improved 
temperature responsive valve which obviates the disadvantages of the prior 
art as mentioned above. 
It is another object of the present invention to provide an improved 
temperature responsive valve which is low in cost and is simple in 
construction. 
According to the present invention, a temperature responsive valve includes 
a bimetal disk which snaps in response to changes in temperature, a rod 
moved by the snapping action of the bimetal disk, a valve member in 
association with movement of the rod to thereby control the flow of fluid, 
and an adjustment member threaded through a body to properly adjust the 
range in movement of the valve member, the adjustment member being secured 
to the body after adjusting operation of the range of movement of the 
valve member.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
In FIG. 1, a temperature responsive valve 1 includes a housing 2 of resin 
material having three ports 4, 5 and 6 and a casing 3 of metal material 
which is secured to housing 2 through an O-ring seal 18. Casing 3 may be 
threaded through the water packet of the engine of the vehicle. A body 7 
of resin material which is positioned within casing 3 has a large diameter 
portion 19 which is secured between housing 2 and casing 3. 
An adjustment member 9 formed of resin material which is the same as body 7 
is positioned within body 7 so that two chambers 11 and 20 are thereby 
defined. Positioned within chamber 20 is a bimetal disk 10 which snaps or 
changes shape from being concave to being convex or vice-versa in response 
to changes in temperature between a first position wherein bimetal 10 is 
curved downwardly and the outer periphery thereof is brought into contact 
with the lower end of body 7, as shown in FIG. 1 and a second position 
wherein bimetal 10 is curved upwardly and the outer periphery thereof is 
spaced from the lower end of body 7. 
Bimetal 10 is continuously upwardly biased by means of a spring 21. A valve 
member 13 is positioned within chamber 11 and is biased by means of a 
spring 12 in a first position where valve member 13 is spaced from a valve 
seat 22 provided on body 7 and is brought into contact with a valve seat 
23 provided on adjustment member 9. Thus, inlet port 4 now communicates 
with outlet port 5 through passage A and is interrupted in communication 
with outlet port 6. 
Valve member 13 is actuated by means of a rod 14 which passes through an 
axial aperture formed in adjustment member 9 with a small gap formed 
therebetween. Namely, the lower end of rod 14 is in contact with bimetal 
10, and an upper end of rod 14 may be spaced from valve member 13 when 
bimetal 10 is in its illustrated initial position. When bimetal 10 snaps 
from the initial position into a second position, valve member 13 is moved 
via rod 14 from its initial position into the second position against 
spring 12. Thus valve member 13 now contacts with seat 22 and is spaced 
from seat 23. Therefore, passage A is now interrupted and inlet port 4 is 
in communication with outlet port 6 via passage B. 
During the above-noted operation, flow of fluid is isolated from chamber 20 
in which bimetal 10 is positioned by means of body 7 and adjustment member 
9 so that bimetal 10 may not be influenced by the temperature of the 
fluid. Thus, bimetal 10 correctly snaps in response to changes in 
temperature, for example, the temperature of engine cooling water, which 
is to be sensed. 
The above-noted adjuster 9 is threaded with bore 8 of body 7. If adjustment 
member 9 is upwardly screwed, the space between seats 22 and 23 will be 
reduced. When adjustment member 9 is loosened, the space between seats 22 
and 23 will be increased. Thus, in response to upwardly screwing and 
loosening of adjustment member 9, the above-noted space will vary and, 
accordingly the range of movement of valve member 13 will be adjustably 
varied. This means that the quantity of fluid flow which is controlled by 
valve member 13 will be properly adjusted. After the above-noted 
adjustment, the lower portions 17 of threaded portions 15 between body 7 
and adjustment member 9 are secured to each other. For example, the 
above-noted lower portions 17 may be welded to each other via a hot or 
burning gas flow which is injected via a nozzle (not shown). Thus, body 7 
and adjustment member 9 are secured after the above-noted adjustment is 
accomplished and adjustment member 9 may be prevented from rotating due to 
vibrations and like circumstances. 
In FIG. 2, showing a second embodiment of the present invention, body 7 has 
a suitable hole 16 which corresponds to or opens into threaded portions 15 
between body 7 and adjustment member 9. Thus, hot or burning gas is 
injected via hole 16 to threaded portions 15, and suitable portions 24 of 
threaded portions 15 may be welded after adjustment which is the same 
procedure as indicated in the previous embodiment. 
Obviously, numerous modifications and variations of the present invention 
are possible in light of the above teachings. It is therefore to be 
understood that within the scope of the appended claims, the invention may 
be practiced otherwise than as specifically described herein.