Valve repsonsive to temperature changes over a limited range

Claim 2

A thermally responsive valve comprising: a. a valve casing having a first coefficient of linear thermal expansion, b. means defining a bore extending longitudinally of said casing, c. a valve core having a coefficient of linear thermal expansion appreciably different than that of said casing slidably received in said bore, d. abutment means positioned in said bore adjacent one end thereof, e. abutment engaging means on said valve core positioned in opposition to said abutment means for engagement therewith upon temperature change, f. stop means positioned adjacent an opposite end of said bore, g. stop engaging means of said valve core positioned in opposition to said stop means, and h. means for urging said stop engaging means into engagement with said stop means.

Claim 3

The valve of claim 1 wherein: a. said stop means comprises an enlarged portion of said bore defining an outwardly projecting shoulder.

Claim 4

The valve of claim 2 wherein: a. said means for urging said stop engaging means into contact with said stop means comprises a spring member mounted in said enlarged portion of said bore and pushing said stop engaging means toward said stop means.

Claim 5

The valve of claim 3 further comprising: a. a retainer extending inwardly of said enlarged portion of said bore in spaced relation to said stop means and in engagement with said spring member, and b. means defining a pocket formed in said core and receiving said spring member.

Claim 6

The valve of claim 1 wherein: a. said stop engaging means comprises an outwardly projecting head formed on one end of said core in overlying relationship to said stop means.

Claim 7

The valve of claim 5 wherein: a. said means urging said head into engagement with said stop means comprises a spring member, and b. a retainer is mounted in said bore in engagement with said spring member and in spaced relationship to said stop means to retain said spring in contact with said core.

Claim 8

The valve of claim 6 further comprising: a. means defining a pocket in said one end of said core receiving said spring member.

Claim 9

A thermally responsive valve comprising: a. a valve casing having a longitudinally extending bore, b. means defining an abutment adjacent one end of said bore and a stop adjacent an opposite end of said bore, c. a valve core slidably received in said bore and having portions adapted to engage said abutment and stop defining means, d. the length and coefficient of linear thermal expansion of said core with respect to the length of said bore and the coefficient of linear thermal expansion of said casing being such that: i. said abutment and stop engaging means engage said abutment and stop, respectively, at a first temperature, ii. said abutment engaging means is spaced from said abutment and said stop engaging means engages said stop at a second temperature lower than said first temperature, and iii. said abutment engaging means engages said abutment and said stop engaging means is spaced from said stop at a third temperature higher than said first temperature.

Claim 10

A thermally responsive valve comprising: a. a valve casing having a longitudinally extending bore, b. means defining an abutment adjacent one end of said bore and a stop adjacent an opposite end of said bore, c. a valve core slidably received in said bore and having portions adapted to engage said abutment and stop defining means, d. the length and coefficient of linear thermal expansion of said core with respect to the length of said bore and the coefficient of linear thermal expansion of said casing being such that: i. said abutment and stop engaging means engage said abutment and stop, respectively, at a first temperature, ii. said abutment engaging means is spaced from said abutment and said stop engaging means engages said stop at a second temperature lower than said first temperature, and iii. said abutment engaging means engages said abutment and said stop engaging means is spaced from said stop at a third temperature higher than said first temperature.

Claim 11

The valve of claim 8 further comprising: a. means defining a flow port, and b. means fixing said valve casing with respect to said flow port with a portion of said valve core positioned in said port, c. said valve core being operative to vary the effective open area of said flow port over a first tempErature range and relatively inoperative to vary said effective open area over a second temperature range.

Claim 12

The valve of claim 8 further comprising: a. a portion of said bore adjacent one end thereof being of reduced cross section, forming an inwardly projecting shoulder defining said abutment, b. a second portion of said bore adjacent an opposite end thereof being of enlarged cross section, forming an outwardly projecting shoulder defining said stop, c. a portion of said core adjacent said one end of said bore defining an outwardly projecting shoulder disposed in opposition to and for engagement with said inwardly projecting shoulder of said bore upon expansion of said core, d. a portion of said core adjacent said opposite end of said bore being of enlarged cross section and defining a head positioned for engagement with said outwardly projecting shoulder of said bore upon contraction of said core, and e. spring means resiliently urging said head into engagement with said outwardly projecting shoulder.

Claim 13

The valve of claim 4 wherein: a. said valve casing has a relatively low coefficient of linear thermal expansion, and b. said valve core has a relatively high coefficient of linear thermal expansion compared to said valve casing.

Claim 14

The valve of claim 7 wherein: a. said valve casing has a relatively low coefficient of linear thermal expansion, and b. said valve core has a relatively high coefficient of linear thermal expansion compared to said valve casing.

Claim 15

The valve of claim 10 wherein: a. said valve casing has a first coefficient of linear thermal expansion, and b. said valve core a coefficient of linear thermal expansion appreciably different than the coefficient of linear thermal expansion of said valve casing.

Claim 16

The valve of claim 13 wherein: a. said valve core has a coefficient of linear thermal expansion substantially greater than the coefficient of linear thermal expansion of said valve casing.