Supervision arrangement for smoke detectors
First Claim
1. In a plug-in sensor unit including a detector base and a detector head constructed and arranged for removable mounting on the detector base and to be locked to the detector base with movement of the detector head relative to the detector base to a locking position, the detector head housing a detector having contacts engaging terminals on the detector base when the detector head is assembled together with the detector base and moved to its locking position, the improvement comprisingcontact means mounted on the detector base adjacent to first and second ones of the terminals, said contact means having a mounting portion connected to the first terminal and a contact portion movable between a first position where it engages the second terminal and a second position where it is disengaged from the second terminal, said contact means interconnecting the first and second terminals when its contact portion is at its first position, and actuating means on the detector head engaging said contact means during mounting of the detector head on the detector base to move said contact portion of said contact means from its second position to its first position, means for retaining said contact portion of said contact means at its first position, and release means operated by said actuating means during removal of the detector head from the detector base allowing said contact portion of said contact means to return to its second position.
1 Assignment
0 Petitions
Accused Products
Abstract
A plug-in sensing unit includes a detector base and a detector head constructed and arranged for mounting on the detector base, with contacts of the detector head engaging terminals of the detector base when the detector head is mounted on the detector base for extending power to a sensor housed within the detector head. A cam on the detector head moves a shorting spring to interconnect a pair of terminals on the detector base to complete a circuit path indicative of the presence of a detector head in the detector base, a further cam on the detector head cooperates with a cam on the detector base to enable the contact spring to restore to its rest position when the detector head is removed from the detector base. The shorting spring can be moved to its operating position manually during testing of the loop in which the detector base is connected, the contact spring being restored to its rest position automatically during the initial stage of mounting of a detector head on the detector base.
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Citations
22 Claims
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1. In a plug-in sensor unit including a detector base and a detector head constructed and arranged for removable mounting on the detector base and to be locked to the detector base with movement of the detector head relative to the detector base to a locking position, the detector head housing a detector having contacts engaging terminals on the detector base when the detector head is assembled together with the detector base and moved to its locking position, the improvement comprising
contact means mounted on the detector base adjacent to first and second ones of the terminals, said contact means having a mounting portion connected to the first terminal and a contact portion movable between a first position where it engages the second terminal and a second position where it is disengaged from the second terminal, said contact means interconnecting the first and second terminals when its contact portion is at its first position, and actuating means on the detector head engaging said contact means during mounting of the detector head on the detector base to move said contact portion of said contact means from its second position to its first position, means for retaining said contact portion of said contact means at its first position, and release means operated by said actuating means during removal of the detector head from the detector base allowing said contact portion of said contact means to return to its second position.
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10. A plug-in sensor unit including a detector base and a detector head constructed and arranged for removable mounting on the detector base and to be locked to the detector base with movement of the detector head relative to the detector base to a locking position, the detector head housing a detector having contacts engaging terminals on the detector base when the detector head is assembled together with the detector base and moved to its locking position, the improvement comprising
a shorting spring mounted on the detector base adjacent to first and second ones of the terminals, the shorting spring having a mounting portion connected to said first terminal and a contact portion movable between a first position where it engages the second terminal and a second position where it is disengaged from the second terminal, the shorting spring electrically interconnecting the first and second terminals when its contact portion is at its first position, and actuating means including cam means on the detector head, and release means, said cam means having first means to move said contact portion of said shorting spring from its second position to its first position during mounting of the detector head on the detector base and to retain said contact portion of said shorting spring at its first position, said cam means having second means cooperating with said release means during removal of the detector head from the detector base allowing said contact portion of said shorting spring, allowing it to return to its second position.
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16. In a plug-in sensor unit including a detector base and a detector head constructed and arranged for movable mounting on the detector base, the detector head having a detector with first and second contacts engaging terminals on the detector base when the detector head is assembled together with the detector base, the improvement comprising
a shorting spring mounted on the detector base adjacent to first and second ones of the terminals, said shorting spring having a mounting portion connected to said first terminal and a contact portion movable between a first position where it engages the second terminal and a second position where it is disengaged from the second terminal, said shorting spring electrically interconnecting the first and second terminals when its contact portion is at its first position, and actuating means including first cam means on the detector head defining a first cam surface for engaging said contact portion during mounting of the detector head on the detector base to move said contact portion from its second position to its first position, and retaining means to retain said contact portion of said shorting spring at its first position, and release means cooperating with said first cam means during removal of the detector head from the detector base to allow said contact portion of said shorting spring to return to its second position.
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21. A method of maintaining conductivity along a selected conductor where the conductor enters and exits a base member as a functional unit engages the base member, the method comprising the steps of:
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providing a short circuit between the conductor entrance and exit; engaging the functional unit with the base while sequentially interrupting the short circuit as the functional unit begins to engage the base member; and restoring the short circuit as the functional unit completes engagement with the base member. - View Dependent Claims (22)
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Specification