US3573700A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Adjustable thermostat
Assignee: Therm O Disc Inc
•
Filing: 1968-11-29
•
Granted: 1971-04-06
•
Expires: 1988-11-29
Abstract
Abstract Bimetal free disc thermostats are disclosed which provide means for modifying the operating temperature of the disc and means for modifying the operating temperature differential of the disc. The operating temperature of the thermostat is adjusted by applying an adjustable biasing force to the snap disc urging it toward one position of stability. Adjustment of the force changes the temperature of operation without materially altering the displacement characteristics of the disc or the operating differential. The stability of the disc calibration is also improved by the biasing force which dampens the snap action. Operating temperature differential is adjusted by a biasing force applied to the disc only when the switch contacts are open. This latter force causes the disc to operate along one curve when the switch is closed and a displaced curve when the switch is open, thereby adjustably reducing operating temperature differential of the disc. A switch operator is arranged so that the kinetic energy of a mass in motion is available to break any contact welds. Further conventional disc structures may be arranged to operate at higher temperatures with relatively small operating temperature differentials by applying properly selected biasing forces to such conventional discs.
Inventors
- 👤 Donald J Schmitt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 08:59
CPC Classifications
H; H01; H01H; H01H37/00; H01H37/02; H01H37/32; H01H37/52; H01H37/54; H01H37/12; H01H37/18
Claims Analysis
Total Claims: 36
Claim 1
Independent Claim
183 words
An adjustable thermostat comprising body means, a switch on said body means including a fixed contact and a mobile contact movable into and out of engagement with said fixed contact to open and close said switch, a bimetallic substantially smoothly dished snap disc supported at its periphery on said body, said snap disc having a central portion movable between first and second positions determined substantially entirely by the dished shape of said disc with snap action in response to temperature changes, operator means operably connected to said central portion operable to open and close said switch in response to movement of said central portion of said snap disc between said positions after said snap disc is in snap motion, an adjustable load means on said thermostat connected to bias said central portion of said disc toward one position with a force which is adjustable, changes in the force of said load means changing the operating temperature of said disc without materially changing said first and second positions and without materially changing the differential temperature of said thermostat as a result of said adjustment.
Claim 2
Dependent Claim
183 words
An adjustable thermostat comprising body means, a switch on said body means including a fixed contact and a mobile contact movable into and out of engagement with said fixed contact to open and close said switch, a bimetallic substantially smoothly dished snap disc supported at its periphery on said body, said snap disc having a central portion movable between first and second positions determined substantially entirely by the dished shape of said disc with snap action in response to temperature changes, operator means operably connected to said central portion operable to open and close said switch in response to movement of said central portion of said snap disc between said positions after said snap disc is in snap motion, an adjustable load means on said thermostat connected to bias said central portion of said disc toward one position with a force which is adjustable, changes in the force of said load means changing the operating temperature of said disc without materially changing said first and second positions and without materially changing the differential temperature of said thermostat as a result of said adjustment.
Claim 3
Dependent Claim
62 words
An adjustable thermostat as set forth in claim 1 wherein said disc is imperforate, and connecting means includes a bumper engageable at one end with the central portion of said disc and engageable at its other end with said mobile contact, said bumper being sized to provide lost motiOn to insure that said disc is in snap motion when said switch operates.
Claim 4
Dependent Claim
23 words
An adjustable thermostat as set forth in claim 2 wherein said load means biases said bumper toward said disc and maintains contact therebetween.
Claim 5
Dependent Claim
36 words
An adjustable thermostat as set forth in claim 3 wherein said disc is peripherally mounted in said body means with axial clearance, and said load means prevents substantial axial movement of said periphery within said clearance.
Claim 6
Dependent Claim
72 words
An adjustable thermostat as set forth in claim 1 wherein said snap disc has a negative spring rate as it moves between said positions, and said load means includes a load spring with a positive spring rate which has an absolute value substantially less than said negative spring rate so that the force thereof applied to said disc does not produce substantial change in the effective negative spring rate of said disc.
Claim 7
Dependent Claim
53 words
An adjustable thermostat as set forth in claim 1 wherein the kinetic energy of the mass in motion of said disc and operator means before contact opening is substantially larger than the kinetic energy of the mass in motion of said mobile contact when said mobile contact is being moved by said disc.
Claim 8
Dependent Claim
67 words
An adjustable thermostat as set forth in claim 6 wherein said fixed contact is mounted on said body means so that it is fixed against movement when said contacts open, and mobile contact support means are provided which are sufficiently rigid to prevent the absorption of appreciable amounts of kinetic energy when movement of said mobile contact is initiated in a direction away from said fixed contact.
Claim 9
Dependent Claim
38 words
An adjustable thermostat as set forth in claim 1 wherein second load means are provided to urge said mobile contact toward said fixed contact with a force which is substantially constant in all positions of said mobile contact.
Claim 10
Dependent Claim
80 words
An adjustable thermostat as set forth in claim 8 wherein said snap disc has a negative spring rate as it moves between said positions and said second load means includes a spring with a spring rate having an absolute value substantially less than said negative spring rate so that the force thereof applied to said mobile contact does not produce a substantial change in the effective negative spring rate of the system when said disc is moving said mobile contact.
Claim 11
Dependent Claim
48 words
An adjustable thermostat as set forth in claim 9 wherein a cantilever mounted mobile contact support is mounted in said body means and said mobile contact is mounted thereon adjacent to its free end, and said operator means engages said cantilever mounted support adjacent to its free end.
Claim 12
Dependent Claim
50 words
An adjustable thermostat as set forth in claim 9 wherein the kinetic energy of the mass in motion of said disc and operator means is substantially larger than the kinetic energy of the mass in motion of said mobile contact when said mobile contact is being moved by said disc.
Claim 13
Dependent Claim
78 words
An adjustable thermostat as set forth in claim 9 wherein said operator means is a bumper engageable at one end with the central portion of said disc and engageable at its other end with said mobile contact, said bumper being proportioned to engage said mobile contact and initiate movement thereof in a direction away from said fixed contact when said snap disc is moving toward a switch open position and is substantially midway between its two said positions.
Claim 14
Dependent Claim
76 words
An adjustable thermostat as set forth in claim 1 wherein said load means is a leaf spring supported in said body at one location and is operatively connected to said operator means at a second location spaced from said one location, and adjusting means are provided at a third location spaced from the other locations to change the force of said load spring on said operator means and thereby change the operating temperature of said thermostat.
Claim 15
Dependent Claim
36 words
An adjustable thermostat as set forth in claim 13 wherein said operator means is connected to said leaf spring intermediate its ends, and said adjustment means is provided adjacent to one end of said leaf spring.
Claim 16
Dependent Claim
66 words
An adjustable thermostat as set forth in claim 1 wherein said body means includes an elongated extension assembly, said disc is mounted on the end of said extension assembly remote from said switch, and said operating means is a rodlike assembly extending the length of said extension, said extension assembly providing means to laterally position said disc and at least an end of said rodlike assembly.
Claim 17
Dependent Claim
27 words
An adjustable thermostat as set forth in claim 1 wherein the force of said adjustable load means on said disc is substantially constant during said snap movement.
Claim 18
Dependent Claim
235 words
An adjustable thermostat comprising body means, a switch on said body including a first fixed contact and a mobile contact movable into and out of engagement with said fixed contact to open and close said switch, a generally circular imperforate bimetal snap disc peripherally mounted on said body means having a central portion movable with snap action between first and second positions in response to temperature changes, bumper means on said body having one end engageable with said central portion of said disc and the other end engageable with said mobile contact, said bumper means being proportioned so that it initiates movement of said mobile contact in a direction away from said fixed contact when said disc is moving toward said second position and is substantially midway between said first and second positions, and adjustable spring means on said thermostat connected to apply an adjustable force to said mobile contact urging it toward said fixed contact whereby adjustment of the force of said spring means changes the temperature differential of disc operation, said spring means having a sufficiently low spring rate so that the force thereon applied to said mobile contact is substantially constant in all positions of said mobile contact, a mobile contact support cantilever mounted on said body means and supporting said mobile contact adjacent to its free end, said bumper being engageable with said mobile contact support adjacent to its free end.
Claim 19
Dependent Claim
235 words
An adjustable thermostat comprising body means, a switch on said body including a first fixed contact and a mobile contact movable into and out of engagement with said fixed contact to open and close said switch, a generally circular imperforate bimetal snap disc peripherally mounted on said body means having a central portion movable with snap action between first and second positions in response to temperature changes, bumper means on said body having one end engageable with said central portion of said disc and the other end engageable with said mobile contact, said bumper means being proportioned so that it initiates movement of said mobile contact in a direction away from said fixed contact when said disc is moving toward said second position and is substantially midway between said first and second positions, and adjustable spring means on said thermostat connected to apply an adjustable force to said mobile contact urging it toward said fixed contact whereby adjustment of the force of said spring means changes the temperature differential of disc operation, said spring means having a sufficiently low spring rate so that the force thereon applied to said mobile contact is substantially constant in all positions of said mobile contact, a mobile contact support cantilever mounted on said body means and supporting said mobile contact adjacent to its free end, said bumper being engageable with said mobile contact support adjacent to its free end.
Claim 20
Dependent Claim
31 words
An adjustable thermostat as set forth in claim 17 wherein said spring applies its force adjacent to the free end of said mobile contact support on the side opposite said bumper.
Claim 21
Dependent Claim
78 words
An adjustable thermostat as set forth in claim 17 wherein said switch includes a second substantially fixed contact means mounted on the side of said mobile contact opposite said first fixed contact, said second fixed contact means being mounted for limited movement with said mobile contact when engaged thereby and providing a stop limiting movement thereof toward said first fixed contact to a predetermined position so that said mobile contact cannot simultaneously engage both of said fixed contacts.
Claim 22
Dependent Claim
216 words
A thermostat comprising body means, a switch mounted on said body means including a fixed contact and a mobile contact movable into and out of engagement with said fixed contact to open and close said switch, a substantially smoothly dished bimetallic snap disc loosely mounted at its periphery in said body with axial clearance and having a central portion movable between first and second positions determined substantially entirely by the dished shape of said disc with snap action in response to temperature changes, operating means connected to open and close said switch in response to movement of said central portion of said disc between said positions after said disc is in snap motion, and adjustable spring means on said body connected to produce a force in all positions of said disc urging said disc toward one of said positions to adjust the operating temperature of said disc and maintain said disc on one side of said clearance, said snap disc having a negative spring rate as it moves between said positions, said load spring having a spring rate having an absolute value which is less than the absolute value of said negative spring rate of said disc, said thermostat being free of positive restraints for limiting the movement of said central portion of said snap disc.
Claim 23
Dependent Claim
216 words
A thermostat comprising body means, a switch mounted on said body means including a fixed contact and a mobile contact movable into and out of engagement with said fixed contact to open and close said switch, a substantially smoothly dished bimetallic snap disc loosely mounted at its periphery in said body with axial clearance and having a central portion movable between first and second positions determined substantially entirely by the dished shape of said disc with snap action in response to temperature changes, operating means connected to open and close said switch in response to movement of said central portion of said disc between said positions after said disc is in snap motion, and adjustable spring means on said body connected to produce a force in all positions of said disc urging said disc toward one of said positions to adjust the operating temperature of said disc and maintain said disc on one side of said clearance, said snap disc having a negative spring rate as it moves between said positions, said load spring having a spring rate having an absolute value which is less than the absolute value of said negative spring rate of said disc, said thermostat being free of positive restraints for limiting the movement of said central portion of said snap disc.
Claim 24
Dependent Claim
63 words
A thermostat as set forth in claim 20 wherein said disc is shaped so that when it is in its free state and unloaded it snaps on increasing temperature at a first temperature, and said spring means produce sufficient force on said disc so that said disc snaps on decreasing temperature at a second temperature which is substantially higher than said first temperature.
Claim 25
Dependent Claim
41 words
A thermostat as set forth in claim 21 wherein said disc when unloaded has a first operating differential temperature, and when loaded by said spring means has a second operating differential temperature which is less than said first operating differential temperature.
Claim 26
Dependent Claim
31 words
A thermostat as set forth in claim 22 wherein said spring means has a sufficiently high spring rate to produce a substantial reduction in the operating differential temperature of said disc.
Claim 27
Dependent Claim
31 words
A thermostat as set forth in claim 20 wherein said spring means has a sufficiently high spring rate to produce a substantial reduction in the operating differential temperature of said disc.
Claim 28
Dependent Claim
74 words
A thermostat as set forth in claim 20 wherein said disc is shaped so that when it is in its free state and unloaded it snaps on rising temperature at a temperature below 250* F. with an operating temperature differential of at least 25* F., and said spring means is operable to cause said disc to snap on rising temperature at above 300* F. with an operating temperature differential of less than 20* F.
Claim 29
Dependent Claim
47 words
A thermostat as set forth in claim 20 wherein adjustment means are provided to adjust the force of said load spring, said load spring having a sufficiently low spring rate so that the force thereof on said disc is substantially constant in all positions of said disc.
Claim 30
Dependent Claim
33 words
A thermostat as set forth in claim 20 wherein the force produced by said spring means urges said operator means toward said disc and maintains said operator means in contact with said disc.
Claim 31
Dependent Claim
238 words
A thermostat comprising body means, a switch mounted on said body means including a fixed contact and a mobile contact movable into and out of engagement with said fixed contact to open and close said switch a substantially smoothly dished bimetallic snap disc loosely mounted at its periphery in said body with axial clearance and having a central portion movable between first and second positions determined substantially entirely by the dished shape of said disc with snap action in response to temperature changes, operating means connected to open and close said switch in response to movement of said central portion of said disc between said positions after said disc is in snap motion, a fixed contact support mounted on said body, said fixed contact being mounted on said fixed contact support, and spring means extending between said fixed contact support and said operating means producing a force in all positions of said disc urging said disc toward one of said positions to modify the operating temperature of said disc and maintain said disc on one side of said clearance, said snap disc having a negative spring rate as it moves between said positions, said spring means having a spring rate having an absolute value which is less than the absolute value of said negative spring rate of said disc, said thermostat being free of positive restraints for limiting the movement of said central portion of said snap disc.
Claim 32
Dependent Claim
238 words
A thermostat comprising body means, a switch mounted on said body means including a fixed contact and a mobile contact movable into and out of engagement with said fixed contact to open and close said switch a substantially smoothly dished bimetallic snap disc loosely mounted at its periphery in said body with axial clearance and having a central portion movable between first and second positions determined substantially entirely by the dished shape of said disc with snap action in response to temperature changes, operating means connected to open and close said switch in response to movement of said central portion of said disc between said positions after said disc is in snap motion, a fixed contact support mounted on said body, said fixed contact being mounted on said fixed contact support, and spring means extending between said fixed contact support and said operating means producing a force in all positions of said disc urging said disc toward one of said positions to modify the operating temperature of said disc and maintain said disc on one side of said clearance, said snap disc having a negative spring rate as it moves between said positions, said spring means having a spring rate having an absolute value which is less than the absolute value of said negative spring rate of said disc, said thermostat being free of positive restraints for limiting the movement of said central portion of said snap disc.
Claim 33
Dependent Claim
57 words
A thermostat as set forth in claim 28 wherein said fixed contact support is formed with an aperture, said operating means is provided with an elongated portion extending through said aperture and a radially extending surface spaced from said fixed contact support, and said spring means extends between said radially extending surface and said fixed contact support.
Claim 34
Dependent Claim
190 words
A thermostat comprising body means, a switch mounted on said body means including a fixed contact and a mobile contact movable into and out of engagement with said fixed contact to open and close said switch, a smoothly dished bimetallic sNap disc mounted on said body means having a central portion movable with snap action between two positions of stability in response to temperature changes, said disc having a negative spring rate as it moves between said positions, operator means connected to open and close said switch in response to movement of said central portion of said disc between said positions after said disc is in snap motion, and adjustable spring means on said body with a positive spring rate having an absolute value which is less than the absolute value of said negative spring rate of said disc applying a force to said central portion in all positions of said disc urging said central portion toward one of said positions, said spring means reducing the differential temperature of said disc, said thermostat being free of positive restraints for limiting the movement of said central portion of said snap disc.
Claim 35
Dependent Claim
190 words
A thermostat comprising body means, a switch mounted on said body means including a fixed contact and a mobile contact movable into and out of engagement with said fixed contact to open and close said switch, a smoothly dished bimetallic sNap disc mounted on said body means having a central portion movable with snap action between two positions of stability in response to temperature changes, said disc having a negative spring rate as it moves between said positions, operator means connected to open and close said switch in response to movement of said central portion of said disc between said positions after said disc is in snap motion, and adjustable spring means on said body with a positive spring rate having an absolute value which is less than the absolute value of said negative spring rate of said disc applying a force to said central portion in all positions of said disc urging said central portion toward one of said positions, said spring means reducing the differential temperature of said disc, said thermostat being free of positive restraints for limiting the movement of said central portion of said snap disc.
Claim 36
Dependent Claim
21 words
A thermostat as set forth in claim 30 wherein adjustment of said spring means changes the operating temperature of said thermostat.
References Cited (Backward Citations)
US1845997A
Cited
US2015545A
Cited
US1958594A
Cited
US1972832A
Cited
US2066162A
Cited
US2039358A
Cited
US2111609A
Cited
US2153297A
Cited
US2331408A
Cited
US3355563A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-04-05 | 1974-10-05 | 1975-04-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-04-05 | 1978-10-05 | 1979-04-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-04-05 | 1982-10-05 | 1983-04-06 | $7700.00 | Window Closed / Lapsed |