US3801767A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pull-apart safety switch with magnetic means for machines
Assignee: Individual
•
Filing: 1972-12-11
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Granted: 1974-04-02
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Expires: 1992-12-11
Abstract
Abstract Several embodiments of pull-apart safety switches are disclosed that are for use in connection with machines from which the operator may be thrown or which he may leave with the machine remaining in motion. Each switch includes a mount to be secured to the machine and a cover so attached to the mount that it may be pulled therefrom. The mount has leads to be included in the machine circuit that is to be controlled. The cover is provided with a flexible member attachable to the operator and of sufficient length to enable him to make normal movements without pulling the cover from the mount. Each switch also has a conductor and means releasably holding it in a first relationship with the contacts when the cover is attached and a second relationship therewith when the cover is pulled free. In one of the two relationships, the control system is operative to maintain the machine in operation. Except when the control circuit is an ignition system having a magneto, said one relationship is the first relationship and in that case, said one relationship is the second relationship. In most embodiments, the cover is magnetically held in place and in second relationship circuit control, the conductor is within the mount and is held from moving into its circuit-closing position until the cover is pulled free, the conductor then being operatively positioned magnetically, resiliently, or by both such means.
Inventors
- 👤 R Marks
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 17:38
CPC Classifications
H; H01; H01H; H01H36/00; H01H35/00; H01H2036/0086; Y; Y10; Y10S; Y10S200/00; Y10S200/02
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
216 words
A pull-apart safety switch for the control circuit of a machine and operable to prevent its operation if its operator is not at a predetermined station, said switch comprising a mount attachable to the machine and including first and second contacts, each a permanent magnet, to which leads of the control circuit are to be connected that enable the operation of the machine to be controlled, a cover attachable to the mount in a manner enabling it to be pulled therefrom, a conductor on the inside of the cover and secured thereto, means releasably holding said conductor in a first relationship with said contacts when said cover is attached to said mount and providing a second relationship with said contacts when said cover is detached from the mount, in one of said relationships, said conductor being seated against said contacts and in the other of said relationships said conductor being disengaged therefrom, and in one of said relationships said control circuit being operative to maintain the machine in operation and in the other of which its operation is prevented, and a flexible conductor secured to said cover with its free end attachable to the operator, said connector being of such length that normal movements of the operator are permitted without pulling the cover from the mount.
Claim 2
Dependent Claim
216 words
A pull-apart safety switch for the control circuit of a machine and operable to prevent its operation if its operator is not at a predetermined station, said switch comprising a mount attachable to the machine and including first and second contacts, each a permanent magnet, to which leads of the control circuit are to be connected that enable the operation of the machine to be controlled, a cover attachable to the mount in a manner enabling it to be pulled therefrom, a conductor on the inside of the cover and secured thereto, means releasably holding said conductor in a first relationship with said contacts when said cover is attached to said mount and providing a second relationship with said contacts when said cover is detached from the mount, in one of said relationships, said conductor being seated against said contacts and in the other of said relationships said conductor being disengaged therefrom, and in one of said relationships said control circuit being operative to maintain the machine in operation and in the other of which its operation is prevented, and a flexible conductor secured to said cover with its free end attachable to the operator, said connector being of such length that normal movements of the operator are permitted without pulling the cover from the mount.
Claim 3
Dependent Claim
252 words
A pull-apart safety switch for the control circuit of a machine and operable to prevent its operation if its operator is not at a predetermined station, said switch comprisng a mount attachable to the machine and including first and second permanent magnet contacts to which leads of the control circuit are to be connected that enable the operation of the machine to be controlled, a cover attachable to the mount in a manner enabling it to be pulled therefrom, said mount having a pocket underlying said contacts, a conductor within said pocket, said pocket of a depth enabling said conductor to have two positions therein defining first and second relationships with said contacts, in one of said positions, the conductor being bottomed in the pocket, means releasably holding said conductor in a first relationship with said contacts when said cover is attached to said mount and providing a second relationship with said contacts when said cover is detached from the mount, in one of said relationships, said conductor being seated against and held by said contacts and in the other of said relationships said conductor being disengaged therefrom, and in one of said relationships said control circuit being operative to maintain the machine in operation and in the other of which its operation is prevented, and a flexible conductor secured to said cover with its free end attachable to the operator, said connector being of such length that normal movements of the operator are permitted without pulling the cover from the mount.
Claim 4
Dependent Claim
252 words
A pull-apart safety switch for the control circuit of a machine and operable to prevent its operation if its operator is not at a predetermined station, said switch comprisng a mount attachable to the machine and including first and second permanent magnet contacts to which leads of the control circuit are to be connected that enable the operation of the machine to be controlled, a cover attachable to the mount in a manner enabling it to be pulled therefrom, said mount having a pocket underlying said contacts, a conductor within said pocket, said pocket of a depth enabling said conductor to have two positions therein defining first and second relationships with said contacts, in one of said positions, the conductor being bottomed in the pocket, means releasably holding said conductor in a first relationship with said contacts when said cover is attached to said mount and providing a second relationship with said contacts when said cover is detached from the mount, in one of said relationships, said conductor being seated against and held by said contacts and in the other of said relationships said conductor being disengaged therefrom, and in one of said relationships said control circuit being operative to maintain the machine in operation and in the other of which its operation is prevented, and a flexible conductor secured to said cover with its free end attachable to the operator, said connector being of such length that normal movements of the operator are permitted without pulling the cover from the mount.
Claim 5
Dependent Claim
104 words
The pull-apart safety switch of claim 2 in which the means operable to hold the conductor in its bottomed position is a member disposed and dimensioned to extend between the contacts and connected to the conductor and the means operable to effect the engagement of the conductor with said contact portions when the cover is pulled from the mount is a resilient diaphragm Of a material that is a non-conductor of electricity connected to said member and biasing it in a direction in which the conductor engages said contact portions but held by the cover when attached to said mount to prevent such engagement.
Claim 6
Dependent Claim
25 words
The pull-apart safety switch of claim 2 in which the means operable to effect the engagement of the conductor with the contact portions are magnetic.
Claim 7
Dependent Claim
245 words
A pull-apart safety switch for a device having an electrical operating source and first and second control circuits, said switch operable to connect said circuits in the alternative to said source, said switch comprising a mount attachable to the device and including first and second contacts one for each circuit and connectable therein, a third contact between said first named contacts, permanent magnets that are non-conductors of electricity, one magnet between the third contact and each of said first named contacts and having opposed forces magnetically connected thereto, a cover attachable to the mount in a manner enabling it to be pulled therefrom, a magnetically responsive conductor within said cover and secured thereto and for engagement with said three contacts when said cover is attached to said mount and a second conductor connectable to said source and including a portion of a magnetically responsive material and engageable with said third and one of said other contacts but resilient and normally spaced therefrom when the cover is attached to said mount, the first conductor being of a mass so much greater than that of the second conductor that said portion of the second member is not magnetically attracted to said magnet until the cover is separated from the mount, and a flexible connector secured to said cover with its free end attachable to the operator, said connector being of such length that normal movements of the operator are permitted without pulling the cover from the mount.
Claim 8
Dependent Claim
245 words
A pull-apart safety switch for a device having an electrical operating source and first and second control circuits, said switch operable to connect said circuits in the alternative to said source, said switch comprising a mount attachable to the device and including first and second contacts one for each circuit and connectable therein, a third contact between said first named contacts, permanent magnets that are non-conductors of electricity, one magnet between the third contact and each of said first named contacts and having opposed forces magnetically connected thereto, a cover attachable to the mount in a manner enabling it to be pulled therefrom, a magnetically responsive conductor within said cover and secured thereto and for engagement with said three contacts when said cover is attached to said mount and a second conductor connectable to said source and including a portion of a magnetically responsive material and engageable with said third and one of said other contacts but resilient and normally spaced therefrom when the cover is attached to said mount, the first conductor being of a mass so much greater than that of the second conductor that said portion of the second member is not magnetically attracted to said magnet until the cover is separated from the mount, and a flexible connector secured to said cover with its free end attachable to the operator, said connector being of such length that normal movements of the operator are permitted without pulling the cover from the mount.
Claim 9
Dependent Claim
41 words
The pull-apart safety switch of claim 5 in which the mounting means for the second conductor is a resilient arm of a material that is not magnetically responsive and yieldably holds the second conductor spaced from said first and third contacts.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-04-01 | 1977-10-01 | 1978-04-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-01 | 1981-10-01 | 1982-04-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-01 | 1985-10-01 | 1986-04-02 | $7700.00 | Window Closed / Lapsed |