Patent US3887909A successfully refreshed from Google Patents.
US3887909A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Alarm device
Assignee: National Presto Industries Inc
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Filing: 1972-04-27
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Granted: 1975-06-03
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Expires: 1992-04-27
Abstract
Abstract An alarm device having an extendible cord control element the outer end of which is attached to an object, such as a window or door, to place the cord in predetermined tension with the cord acting directly on a switch arm to effect an alarm signal upon a change in tension of the cord resulting from breaking or pulling thereof.
Inventors
- 👤 John L Beiswenger
- 👤 Leland Devon Jorgensen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 23:25
CPC Classifications
G; G08; G08B; G08B13/00; G08B13/02; G08B13/08; G08B17/00; G08B17/06
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
279 words
An alarm device for use in detecting movement of an object, comprising, in combination, housing means, electrically operated alarm generating means supported by said housing means, a source of electrical energy supported by said housing means, circuit means selectively electrically connecting said alarm generating means to said source of electrical energy, said circuit means including switch means having a pair of spaced fixed contacts and a movable contact arm therebetween and biasing means urging the movable contact arm to one and away from the other of said fixed contacts, said movable contact arm and fixed contacts being connected in said circuit such that said circuit means is closed when said contact arm is contacting either of said fixed contacts and open when said contact arm is disposed intermediate said fixed contacts, a rotatable reel member, means including a length of cord wound about said rotatable reel member, and releasable clutch means for resisting rotation of said reel member, said cord means acting directly on said movable contact arm and having its free end adapted to be secured to the object, said clutch means being releasable to permit unwinding of said cord means from said reel member to facilitate attachment of said cord means to the object and to take up slack in said cord means to place said cord means under tension of an amount sufficient to resist the force of the biasing means and hold said contact arm intermediate and out of engagement with said fixed contacts, whereby when said cord means is pulled, broken or otherwise disturbed said contact arm will be caused to contact one of said fixed contacts and to energize said alarm gEnerating means.
Claim 2
Dependent Claim
279 words
An alarm device for use in detecting movement of an object, comprising, in combination, housing means, electrically operated alarm generating means supported by said housing means, a source of electrical energy supported by said housing means, circuit means selectively electrically connecting said alarm generating means to said source of electrical energy, said circuit means including switch means having a pair of spaced fixed contacts and a movable contact arm therebetween and biasing means urging the movable contact arm to one and away from the other of said fixed contacts, said movable contact arm and fixed contacts being connected in said circuit such that said circuit means is closed when said contact arm is contacting either of said fixed contacts and open when said contact arm is disposed intermediate said fixed contacts, a rotatable reel member, means including a length of cord wound about said rotatable reel member, and releasable clutch means for resisting rotation of said reel member, said cord means acting directly on said movable contact arm and having its free end adapted to be secured to the object, said clutch means being releasable to permit unwinding of said cord means from said reel member to facilitate attachment of said cord means to the object and to take up slack in said cord means to place said cord means under tension of an amount sufficient to resist the force of the biasing means and hold said contact arm intermediate and out of engagement with said fixed contacts, whereby when said cord means is pulled, broken or otherwise disturbed said contact arm will be caused to contact one of said fixed contacts and to energize said alarm gEnerating means.
Claim 3
Dependent Claim
279 words
An alarm device for use in detecting movement of an object, comprising, in combination, housing means, electrically operated alarm generating means supported by said housing means, a source of electrical energy supported by said housing means, circuit means selectively electrically connecting said alarm generating means to said source of electrical energy, said circuit means including switch means having a pair of spaced fixed contacts and a movable contact arm therebetween and biasing means urging the movable contact arm to one and away from the other of said fixed contacts, said movable contact arm and fixed contacts being connected in said circuit such that said circuit means is closed when said contact arm is contacting either of said fixed contacts and open when said contact arm is disposed intermediate said fixed contacts, a rotatable reel member, means including a length of cord wound about said rotatable reel member, and releasable clutch means for resisting rotation of said reel member, said cord means acting directly on said movable contact arm and having its free end adapted to be secured to the object, said clutch means being releasable to permit unwinding of said cord means from said reel member to facilitate attachment of said cord means to the object and to take up slack in said cord means to place said cord means under tension of an amount sufficient to resist the force of the biasing means and hold said contact arm intermediate and out of engagement with said fixed contacts, whereby when said cord means is pulled, broken or otherwise disturbed said contact arm will be caused to contact one of said fixed contacts and to energize said alarm gEnerating means.
Claim 4
Dependent Claim
279 words
An alarm device for use in detecting movement of an object, comprising, in combination, housing means, electrically operated alarm generating means supported by said housing means, a source of electrical energy supported by said housing means, circuit means selectively electrically connecting said alarm generating means to said source of electrical energy, said circuit means including switch means having a pair of spaced fixed contacts and a movable contact arm therebetween and biasing means urging the movable contact arm to one and away from the other of said fixed contacts, said movable contact arm and fixed contacts being connected in said circuit such that said circuit means is closed when said contact arm is contacting either of said fixed contacts and open when said contact arm is disposed intermediate said fixed contacts, a rotatable reel member, means including a length of cord wound about said rotatable reel member, and releasable clutch means for resisting rotation of said reel member, said cord means acting directly on said movable contact arm and having its free end adapted to be secured to the object, said clutch means being releasable to permit unwinding of said cord means from said reel member to facilitate attachment of said cord means to the object and to take up slack in said cord means to place said cord means under tension of an amount sufficient to resist the force of the biasing means and hold said contact arm intermediate and out of engagement with said fixed contacts, whereby when said cord means is pulled, broken or otherwise disturbed said contact arm will be caused to contact one of said fixed contacts and to energize said alarm gEnerating means.
Claim 5
Dependent Claim
49 words
An alarm device as defined in claim 1 wherein said movable contact arm has an opening therein, and wherein said cord means passes through said opening and acts upon said contact arm to effect movement thereof when the tension in said cord is varied from said tension placed thereon.
Claim 6
Dependent Claim
45 words
An alarm device as defined in claim 1 wherein said reel member is mounted within said housing and includes a flange portion extending outwardly of said housing to allow said reel member to be rotated through movement of said flange portion externally of said housing.
Claim 7
Dependent Claim
63 words
An alarm device as defined in claim 1 wherein said source of electrical energy comprises a pair of DC batteries normally connected in series, said circuit means having a pair of separable contacts normally connecting said batteries in series, and including means adapted to be inserted between said last mentioned contacts to separate the same and open said series connection between said batteries.
Claim 8
Dependent Claim
46 words
An alarm device as defined in claim 1 wherein said reel member is mounted within said housing for rotation about its longitudinal axis, and wherein said movable contact arm of said switch means is mounted for pivotal movement about the axis of rotation of said reel.
Claim 9
Dependent Claim
212 words
An alarm device comprising, in combination, housing means, electrically operated alarm generating means supported by said housing means, a source of electrical energy supported by said housing means, circuit means selectively electrically connecting said alarm generating means to said electrical energy source, said circuit means including switch means comprising a pair of fixed contacts and a movable contact arm swingable therebetween, and biasing means urging the movable contact arm to one of said fixed contacts and away from the other, a rotatable reel having a length of cord wound thereabout and spring-biased, releasable clutch means for resisting rotation of said reel, said cord passing through a provided opening in one end of said contact arm and having its free end adapted for attachment to an object, said clutch means being releasable to permit unwinding of the cord therefrom to facilitate attachment of said cord to such object and to take up slack in the cord sufficiently to place the cord under tension and hold the contact arm out of engagement with the fixed contacts and against the force of the biasing means whereby when the cord is pulled, broken or otherwise disturbed the contact arm will be caused to contact one of the fixed contacts and to energize the alarm generating means.
Claim 10
Dependent Claim
212 words
An alarm device comprising, in combination, housing means, electrically operated alarm generating means supported by said housing means, a source of electrical energy supported by said housing means, circuit means selectively electrically connecting said alarm generating means to said electrical energy source, said circuit means including switch means comprising a pair of fixed contacts and a movable contact arm swingable therebetween, and biasing means urging the movable contact arm to one of said fixed contacts and away from the other, a rotatable reel having a length of cord wound thereabout and spring-biased, releasable clutch means for resisting rotation of said reel, said cord passing through a provided opening in one end of said contact arm and having its free end adapted for attachment to an object, said clutch means being releasable to permit unwinding of the cord therefrom to facilitate attachment of said cord to such object and to take up slack in the cord sufficiently to place the cord under tension and hold the contact arm out of engagement with the fixed contacts and against the force of the biasing means whereby when the cord is pulled, broken or otherwise disturbed the contact arm will be caused to contact one of the fixed contacts and to energize the alarm generating means.
Claim 11
Dependent Claim
20 words
An alarm device as defined in claim 6 wherein said free end of the cord has a magnet attached thereto.
Claim 12
Dependent Claim
47 words
An alarm device as defined in claim 6 wherein the circuit means includes a pair of separable contacts aligned with an opening in the housing through which a removable electrical insulating member is insertable to separate the contacts and open the circuits to disable the alarm device.
Claim 13
Dependent Claim
104 words
An alarm device as defined in claim 6 wherein the reel and movable contact arm are mounted to independently turn on a common axis located to one side of and spaced from the opening in the contact arm through which the cord passes, said housing having a further opening therein spaced from and to the opposite side of said opening in the contact arm through which the cord is also threaded, said opening being so related that the reel may be rotated on its axis to take up slack in the cord and thereby to center the contact arm spaced between the fixed contacts.
Claim 14
Dependent Claim
47 words
An alarm device as defined in claim 6 including thermostat means supported by said housing means and connected in circuit with said circuit means, said thermostat means being adapted to effect energizing of said alarm generating means when a predetermined temperature surrounding said thermostat means is reached.
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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) | 1978-06-02 | 1978-12-02 | 1979-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-02 | 1982-12-02 | 1983-06-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-02 | 1986-12-02 | 1987-06-03 | $7700.00 | Window Closed / Lapsed |