Automobile thermostat

Claim 2

An automobile thermostat comprising valve means including an annular valve seat and a movable valve member cooperating with said valve seat to control a flow of coolant through said valve means; bias means acting on said valve member to force said valve member toward said valve seat; and an operator member acting on said valve member to force said valve member away from said valve seat and being constructed of a material having a temperature-actuated shape memory; said operator member including a coiled spring being disposed upstream of said valve means to sense the temperature of the coolant and having a tightly coiled distorted shape when the coolant temperature is below a predetermined operating temperature and a loosely coiled initial shape when the coolant temperature is above the predetermined operating temperature whereby said operating member undergoes a rapid transition from the distorted shape to the initial shape to overcome said bias means to move said valve member away from said valve seat and open said valve means when the coolant temperature increases above the predetermined operating temperature.

Claim 3

The invention as recited in claim 1 wherein said material is an alloy having a composition of 55 percent nickel by weight with the remainder being essentially titanium.

Claim 4

The invention as recited in claim 1 wherein said valve means includes stationary support means supporting said valve seat and movable support means connected and movable with said valve member, said bias means is mounted between said stationary support means and said valve member, and said operator member is mounted between said stationary support means and said movable support means.

Claim 5

The invention as recited in claim 3 wherein said stationary support means includes a cup-shaped housing, said valve member includes a cylindrical wall disposed Concentrically around said housing, said operator member is disposed within said housing, and said bias means is disposed within said cylindrical wall of said valve member and around said housing.

Claim 6

The invention as recited in claim 4 wherein said housing has an outwardly extending bottom lip, said valve member has a shoulder extending inwardly and transversely from one end of said cylindrical wall, and said bias means is a coil spring mounted in compression between said lip and said shoulder.

Claim 7

An automobile thermostat comprising valve means including stationary support means including a cup-shaped housing having an annular valve seat and an outwardly extending bottom lip, movable support means including a cylindrical wall disposed concentrically around said housing and an annular valve member cooperating with said annular valve seat to control a flow of coolant therethrough, a shoulder extending inwardly and transversely from one end of said cylindrical wall; bias means including a coil spring mounted in compression between the bottom lip on said housing and the shoulder on said cylindrical wall, said coil spring being disposed within said cylindrical wall and around said housing; an operator member acting on said valve member to force said valve member away from said valve seat and being constructed of a material having a temperature-actuated shape memory; said operator member being disposed upstream of said valve means to sense the temperature of the coolant and having a distorted shape when the coolant temperature is below a predetermined operating temperature and an initial shape when the coolant temperature is above the predetermined operating temperature whereby said operating member undergoes a rapid transition from the distorted shape to the initial shape to overcome said bias means to move said valve member away from said valve seat and open said valve means when the coolant temperature increases above the predetermined operating temperature; said movable support means including a first plate attached to the other end of said cylindrical wall and having a central recess aligned with said housing; and said operator member being a coiled spring mounted in compression between the bottom of said housing and the central recess of said first plate, said coiled spring having a loosely coiled initial shape and a tightly coiled distorted shape.

Claim 8

An automobile thermostat comprising valve means including stationary support means including a cup-shaped housing having an annular valve seat and an outwardly extending bottom lip, movable support means including a cylindrical wall disposed concentrically around said housing and an annular valve member cooperating with said annular valve seat to control a flow of coolant therethrough, a shoulder extending inwardly and transversely from one end of said cylindrical wall; bias means including a coil spring mounted in compression between the bottom lip on said housing and the shoulder on said cylindrical wall, said coil spring being disposed within said cylindrical wall and around said housing; an operator member acting on said valve member to force said valve member away from said valve seat and being constructed of a material having a temperature-actuated shape memory; said operator member being disposed upstream of said valve means to sense the temperature of the coolant and having a distorted shape when the coolant temperature is below a predetermined operating temperature and an initial shape when the coolant temperature is above the predetermined operating temperature whereby said operating member undergoes a rapid transition from the distorted shape to the initial shape to overcome said bias means to move said valve member away from said valve seat and open said valve means when the coolant temperature increases above the predetermined operating temperature; said movable support means including a first plate attached to the other end of said cylindrical wall and having a central recess aligned with said housing; and said operator member being a coiled spring mounted in compression between the bottom of said housing and the central recess of said first plate, said coiled spring having a loosely coiled initial shape and a tightly coiled distorted shape.

Claim 9

The invention as recited in claim 6 wherein said stationary support means includes a second plate secured to said bottom lip and having a second lip in parallel spaced relation with said bottom lip, and an annular seal is disposed between said bottom lip and said second lip and contacts said cylindrical wall.

Claim 10

The invention as recited in claim 7 wherein said first plate is attached to the other end of said cylindrical wall by a plurality of equally spaced legs extending from said central recess, said central recess has an aperture in the center thereof, and said valve member has a second cylindrical wall extending from said shoulder and in sliding contact with said housing.

Claim 11

The invention as recited in claim 8 wherein said material is an alloy having a composition of 55 percent nickel by weight with the remainder being essentially titanium.