US3899783A - Mechanical alarm sounding failure of electrical system - Google Patents

Abstract

A device for sounding an alarm when electric power fails using a first member freely rotatable about an axis; a windup spring connected to the member and wound up when the member is rotated through an arc in one direction; first means responsive to normal flow to rotate the member in said one direction through said arc and to hold the member in said position when said current flows, the means releasing the member when current ceases. The spring unwinds and actuates to sound the alarm.

Description

United States Patent Kuzmar et al.

[451 Aug. 12, 1975 MECHANICAL ALARM SOUNDING FAILURE OF ELECTRICAL SYSTEM Inventors: Edward Kuzmar; Mary Kuzmar,

both of 4407 S. Campbell Ave., Chicago, HI. 60632 Filed: Aug. 15, i973 Appl. No.: 388,627

US. Cl. 340/253 C; 340/248 B Int. Cl. G08B 21/00 Field of Search 340/253 C, 248 B References Cited FOREIGN PATENTS OR APPLICATIONS 12/1926 Germany 340/253 C Primary Examiner-John W. Caldwell Assistant ExaminerDaniel Myer 5 7 ABSTRACT A device for sounding an alarm when electric power fails using a first member freely rotatable about an axis; a windup spring connected to the member and wound up when the member is rotated through an arc in one direction; first means responsive to normal flow to rotate the member in said one direction through said are and to hold the member in said position when said current flows, the means releasing the member when current ceases. The spring unwinds and actuates to sound the alarm.

3 Claims, 1 Drawing Figure MECHANICAL ALARM SOUNDING FAILURE OF ELECTRICAL SYSTEM SUMMARY OF THE INVENTION Our invention is directed toward a device used with an electric clock such as employed in a clock radio to sound an alarm when the electric power fails. The alarm is mechanically rather than electrically operated whereby it is not likely to fail itself.

A flat member, in accordance with our invention, is freely rotatable about an axis. A windup spring is connected to the member and is wound up when the member is rotated through an arc in one direction. First means responsive to normal current flow rotates the member through said are in said direction and holds the member in this position as long as current flows. However, the means releases or ceases to hold the member in said position when the current is interrupted whereby the member rotates in opposite position through said arc, and the spring unwinds. Second means operated by the unwinding spring sounds the desired alarm, thus carrying out the purposes of the invention.

BRIEF DESCRlPTlON OF THE DRAWINGS The accompanying FIGURE shows a preferred embodiment of our invention, shown in the position assumed after current failure,

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS:

When current is supplied to an electric clock 34 via plug and conductors 12, a circuit is completed through winding 14 of a relay and a normally closed contact set 16 thereof. The winding is energized.

A flat oval shaped member 18 is freely rotatable about an axis 20 centered in a centrally disposed cross piece 22 of the member. Piece 22 has an offset prong 24 riding in a longitudinally extending slot 26 with free end of plunger 29. When winding 14 is energized, the plunger 29 is pulled in, and the piece 22 is rotated clockwise.

A windup spring 28 secured to the member 18 at one end is wound up by this clockwise motion. Spring 28 is associated with ratchet pawl 32 and gear 30 to prevent the alarm from being sounded while the spring is wound up. The spring cannot unwind as long as the member is held by magnetic pawl 36 as explained below. As the clock motor 34 is energized by another circuit through the plug at the same time that winding 14 is energized, magnetic pawl 36 is attracted and pivoted toward the motor causing the pawl arm 38 to swing toward member 18 and prong 40 at the end of the arm to engage grooves 42 to hold the member in the clockwise position.

When the current fails, the motor stops, and the pawl 36 is released by pull of spring 48. This action causes prong 40 to be removed from grooves 42. At the same time, winding 14 is deenergized, pushing plunger 29 outward. Plunger 29 then moves prong 24' to swing member 18 into the position shown in the FIGURE.

This winds up the spring. The spring unwinds. The spring rotates gear 30 and gear 35 carrying gear 30. Gear 35 rotates gear 66. Gear 66 causes small arm 68 of L shaped linkage to pivot up and down about pivot point 72 at the intersection of small arm 68 and large arm 44 of the linkage against the pull of loading spring 76. Arm 44 is thus pivoted back and forth as shown with hammer 78 on the free end of arm 44 striking gong 50 on each forward stroke to sound the alarm.

When current is restored, the cycle will again be repeated, with winding 14 energized and member 18 being rotated back to its original position and held in place by prong 40 engaging grooves 42.

While we have described our invention with particular reference to the drawings, such is not to be considered as limiting its actual scope.

Having thus described this invention, what is asserted as new is:

l. A device for sounding an alarm when electrical power fails, said device comprising:

a fiat oval shaped member having a central opening spanned by a cross piece, said member being freely rotatable about an axis extending at right angles through the center of the cross piece, said member having a prong which is parallel to said axis and is secured to said cross piece offset from the center;

an electric relay having a winding energized when said power is present and deenergized when said power fails, and a plunger pulled in when the winding is energized and pushed out when the winding is deenergized, said plunger having a longitudinal slot in its free end, said slot being engaged by said prong, movement of the plunger causing rotation of the member, whereby the member is rotated in one direction to a first position when the plunger is pulled in and is rotated in opposite direction to a second position when the plunger is pushed out; windup spring connected at one end to said member, said spring being wound up when the member is rotated from the first position to the second position and being free to unwind when the member is in the second position, said spring being prevented from unwinding when the member is in the first position; and

means including a gong and hammer, said means being actuated by said spring as it unwinds to cause the hammer to repeatedly strike and move away from the gong to sound the alarm.

2. The device of claim 1 wherein said member has spaced teeth disposed along a portion of the outer periphery and further including additional magnetic means actuated when power is present to engage said teeth and hold the member in the first position and deactuated when power is absent to be disengaged from the teeth and allow said member to rotate.

3. The device of claim 2 wherein the magnetic means includes a magnetic pawl having an arm extending outward therefrom, said arm having an additional prong at its free end movable into and out of engagement with said member teeth.

Claims (3)

1. A device for sounding an alarm when electrical power fails, said device comprising: a flat oval shaped member having a central opening spanned by a cross piece, said member being freely rotatable about an axis extending at right angles through the center of the cross piece, said member having a prong which is parallel to said axis and is secured to said cross piece offset from the center; an electric relay having a winding energized when said power is present and deenergized when said power fails, and a plunger pulled in when the winding is energized and pushed out when the winding is deenergized, said plunger having a longitudinal slot in its free end, said slot being engaged by said prong, movement of the plunger causing rotation of the member, whereby the member is rotated in one direction to a first position when the plunger is pulled in and is rotated in opposite direction to a second position when the plunger is pushed out; a windup spring connected at one end to said member, said spring being wound up when the member is rotated from the first position to the second position and being free to unwind when the member is in the second position, said spring being prevented from unwinding when the member is in the first position; and means including a gong and hammer, said means being actuated by said spring as it unwinds to cause the hammer to repeatedly strike and move away from the gong to sound the alarm.

2. The device of claim 1 wherein said member has spaced teeth disposed along a portion of the outer periphery and further including additional magnetic means actuated when power is present to engage said teeth and hold the member in the first position and deactuated when power is absent to be disengaged from the teeth and allow said member to rotate.

3. The device of claim 2 wherein the magnetic means includes a magnetic pawl having an arm extending outward therefrom, said arm having an additional prong at its free end movable into and out of engagement with said member teeth.

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