US3812306A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Switching mechanism
Assignee: Deltrol Corp
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Filing: 1972-08-23
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Granted: 1974-05-21
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Expires: 1992-08-23
Abstract
Abstract Protection against refrigeration compressor burnout by short cycling is provided by a time delay switching mechanism having a motor and a solenoid controlled by a room thermostat. The motor runs continuously and the solenoid stops and starts the timer by stalling or releasing the timer gear. The timer gear has teeth omitted at the stalling points to allow the motor to run free. A starter cam follower bearing on a starter cam serves to start the timer gear when released by the solenoid. The solenoid operates the stalling and switch control mechanism through a compound leverage and camming system compensating for the non-linear pull curve of the solenoid. The device also includes a combination cam and latch operated switch in which one switch blade carries a follower lifting another blade which is then held by the latch when the follower drops to close the switch. A manual operator is provided for closing the switch independently of the timing mechanism. This manual operator is released automatically by the solenoid dropping out when the thermostat becomes satisfied. The timer also includes an arrangement for locking the compressor switch closed for a period of time when it first closes to allow the system to settle down and thus avoid short cycling.
Inventors
- 👤 J Harris
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 10:06
CPC Classifications
H; H01; H01H; H01H50/00; H01H50/64; H01H50/643; H01H50/644; H01H43/00; H01H43/02; H01H43/026; H01H43/028
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
173 words
In a timing device, the combination of, a cam, a first switch blade having one end anchored and the other end free, a second switch blade having one end anchored and the other end free, said first blade being located between the cam and said second blade and both blades being biased toward the cam, cooperating electrical contact surfaces carried by said blades, a cam follower carried by and attached to said second blade, said cam follower extending past the first blade and riding the cam, said cam follower being constructed and arranged to lift both blades against their bias with the contact surfaces disengaged, said cam having a lobe arranged to lift the cam follower and then lower it whereby both blades are raised and the second blade is lowered, a latch constructed and arranged to hold the first blade in lifted position whereby the contact surfaces engage when the second blade is lowered by the cam, and means for releasing said latch from the first blade to separate said contact surfaces.
Claim 2
Dependent Claim
173 words
In a timing device, the combination of, a cam, a first switch blade having one end anchored and the other end free, a second switch blade having one end anchored and the other end free, said first blade being located between the cam and said second blade and both blades being biased toward the cam, cooperating electrical contact surfaces carried by said blades, a cam follower carried by and attached to said second blade, said cam follower extending past the first blade and riding the cam, said cam follower being constructed and arranged to lift both blades against their bias with the contact surfaces disengaged, said cam having a lobe arranged to lift the cam follower and then lower it whereby both blades are raised and the second blade is lowered, a latch constructed and arranged to hold the first blade in lifted position whereby the contact surfaces engage when the second blade is lowered by the cam, and means for releasing said latch from the first blade to separate said contact surfaces.
Claim 3
Dependent Claim
190 words
In a timing device, the combination of, a cam, a first switch blade having one end anchored and the other end free, a second switch blade having one end anchored and the other end free, said first blade being located between the cam and said second blade and both blades being biased toward the cam, cooperating electrical contact surfaces carried by said blades, cam follower means for lifting the blades, said cam and cam follower means being constructed and arranged to first lift the blades against their bias with the contact surfaces separated and then lower the blades, latch means constructed and arranged to hold the first blade in lifted position for engaging the contact surfaces when the second blade is lowered by the cam, means for releasing the latch means from the first blade to separate the contact surfaces, manual operator means constructed and arranged to engage the contact surfaces independently of the cam, said manual operator means being arranged to lift the first blade sufficiently to engage said surfaces and to hold this blade in lifted position and means for releasing the manual operator means from holding position.
Claim 4
Dependent Claim
190 words
In a timing device, the combination of, a cam, a first switch blade having one end anchored and the other end free, a second switch blade having one end anchored and the other end free, said first blade being located between the cam and said second blade and both blades being biased toward the cam, cooperating electrical contact surfaces carried by said blades, cam follower means for lifting the blades, said cam and cam follower means being constructed and arranged to first lift the blades against their bias with the contact surfaces separated and then lower the blades, latch means constructed and arranged to hold the first blade in lifted position for engaging the contact surfaces when the second blade is lowered by the cam, means for releasing the latch means from the first blade to separate the contact surfaces, manual operator means constructed and arranged to engage the contact surfaces independently of the cam, said manual operator means being arranged to lift the first blade sufficiently to engage said surfaces and to hold this blade in lifted position and means for releasing the manual operator means from holding position.
Claim 5
Dependent Claim
24 words
A device as recited in claim 2 including means actuated with the latch means in releasing the same for releasing the manual operator means.
Claim 6
Dependent Claim
33 words
A device as recited in claim 2 in which the manual operator means is arranged to lift the first blade sufficiently to maintain the contact surfaces engaged for all positions of the cam.
Claim 7
Dependent Claim
54 words
A device as recited in claim 2 in which the latch means is pivoted and the manual operator means consists of a camming member mounted on the same axis as the latch means pivot, the camming member engaging the first blade adjacent the latch means and having a lifting surface and a holding surface.
Claim 8
Dependent Claim
108 words
In an automatic controL device, a control switch having a first position and a second position, automatic means for operating said control switch from its first position to its second position at one time and for operating said switch from the second position back to the first position at another time, manual means separate from said automatic means for operating said switch to its second position independently of the automatic means, said manual means being arranged to hold said switch in the second position without manual effort, and means actuated by the automatic means in returning the switch back to the first position for releasing said manual means.
Claim 9
Dependent Claim
108 words
In an automatic controL device, a control switch having a first position and a second position, automatic means for operating said control switch from its first position to its second position at one time and for operating said switch from the second position back to the first position at another time, manual means separate from said automatic means for operating said switch to its second position independently of the automatic means, said manual means being arranged to hold said switch in the second position without manual effort, and means actuated by the automatic means in returning the switch back to the first position for releasing said manual means.
Claim 10
Dependent Claim
55 words
The combination recited in claim 1 in which the cam follower is attached only to the second blade and is arranged to engage the first blade when being lifted by the cam, said cam follower disengaging the first blade when it is lowered by the cam and the first blade is held by the latch.
Claim 11
Dependent Claim
28 words
The combination recited in claim 1 in which the cam follower is located adjacent the contact surfaces and determines the positions thereof independently of flexure of the blades.
Claim 12
Dependent Claim
167 words
In a timing device, the combination, a cam, a first switch blade having one end anchored and the other end free, a second switch blade having one end anchored and the other end free, said first blade being located between the cam and second blade and both blades being biased toward the cam, cooperating electrical contact surfaces carried by said blades, a cam follower carried by and attached to the second blade, said cam follower being formed of insulative material and riding the cam, said cam follower being constructed and arranged to lift both blades against their bias with the contact surfaces disengaged, said cam having a lobe arranged to lift the cam follower and then lower it whereby both blades are raised and the second blade is lowered, and holding means constructed and arranged to hold the first blade in lifted position whereby the contact surfaces engage when the second blade is lowered by the cam, said holding means being releasable to separate the contact surfaces.
Claim 13
Dependent Claim
167 words
In a timing device, the combination, a cam, a first switch blade having one end anchored and the other end free, a second switch blade having one end anchored and the other end free, said first blade being located between the cam and second blade and both blades being biased toward the cam, cooperating electrical contact surfaces carried by said blades, a cam follower carried by and attached to the second blade, said cam follower being formed of insulative material and riding the cam, said cam follower being constructed and arranged to lift both blades against their bias with the contact surfaces disengaged, said cam having a lobe arranged to lift the cam follower and then lower it whereby both blades are raised and the second blade is lowered, and holding means constructed and arranged to hold the first blade in lifted position whereby the contact surfaces engage when the second blade is lowered by the cam, said holding means being releasable to separate the contact surfaces.
Claim 14
Dependent Claim
42 words
The combination recited in claim 9 in which the first blade is formed with a slot and the cam follower extends freely through the slot and includes a portion extending under the first blade adjacent the slot for lifting said first blade.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-05-20 | 1977-11-19 | 1978-05-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-05-20 | 1981-11-19 | 1982-05-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-05-20 | 1985-11-19 | 1986-05-21 | $7700.00 | Window Closed / Lapsed |