US2721532A - Prowler alarm - Google Patents

Description

Oct. 25, 1955 F. A. HICKERNELL PROWLER ALARM Filed March 4, 1954 FRED A. HICKERNELL United States Patent PROWLER ALARM Fred A. Hickernell, Phoenix, Ariz.

Application March 4, 1954, Serial No. 414,059

3 Claims. (Cl. 116-94) This invention pertains to prowler alarms.

One of the objects of the invention is to provide a prowler alarm which can be easily and cheaply made and easily installed on a door frame of any common door;

Another object is to provide such an alarm which is composed of parts which are not apt to get out of adjustment;

Another object is to provide such an alarm which has a very simple and expedient mechanism for releasing the alarm and giving a loud audible signal; said setting and releasing mechanism being constructed so that any tampering with, opening, closing, or partial opening or closing of the door adjacent to which the alarm is fixed will cause the signal to be given; further, the alarm is arranged so that if any attachment means between it and the door is tampered with and an attempt made to render it inoperative, the signal will be given.

Other objects will appear hereinafter.

I attain the foregoing objects by means of the construction, and devices, and combination of parts illustrated in the accompanying drawings, in which Figure 1 is a front elevational view of the alarm as installed on the top frame of a door;

Figure 2 is a side elevation thereof with the door frame and door sectioned off along line 2--2 of Figure 1; and

Figure 3 is a view of the alarm body with portions of the case sectioned off along line 3-3 of Figure 2, drawn on a somewhat enlarged scale.

Similar numerals refer to similar parts in the several views.

In the drawing numeral 2 indicates the base body of the alarm. This is attached to door frame 4 by screws driven through brackets 3 in the lower part of the body 2.

A shaft 6 extends outward from the center of body 2 and a cup-shaped case 5 having a cylindrical rim is mounted on shaft 6 to turn freely thereon.

Two arms 7 and 8 are attached to the rim of case 5 and extend radially outward thereon. These arms each carry clappers 9 on resilient spring-like stems 10.

Within case 5 there is a spiral spring 18. The inner end of this spring is attached to shaft 6 at 19 and the outer end of the spring is attached to the rim of the case by rivet 20. A spiral spring gong 21 is attached to a boss 22 positioned within the upper portion of body 2. This gong is so disposed that clappers 9 will strike it when case 5 and arms 7 and 8 are rotated around shaft 6. A latch 24 is pivoted at 25 to the lower right-hand side of body 2. This has a hook 26 at its outer end which is adapted to engage above either one of arms 7 or 8 in order to secure them in position after spring 18 has been wound.

In order to set the alarm the arms 7 and 8 are turned, together with case 5', to wind up spring 18. After this is done a setting thimble 28, which has an axial opening sufiicient to receive the end portion of either one of arms 7 and 8, is slipped on to one of these arms. A ring 29 is provided at the outer end of this setting thimble which is connected by a fine wire or thread 30 to a moving part of door 32 by a bracket 33.

2,721,532 Patented Oct. 25, 1955 With the spring 18 wound and with one of the arms engaged, and the thimble 28 attached to the door 32, it will be understood that any movement of the door will pull the thimble from the end of the arm 8 (or 7) and free the arms from restraint, whereupon they will rotate about the shaft 6 and clappers 9 will contact gong 21. This produces considerable noise for a duration of time dependent upon the length and size of spring 18. A sudden disturbance such as is made by gong 21 is usually sufficient to scare away the ordinary prowler type of thief, and give the owner of the premises notice that the door has been disturbed. It is to be observed that any motion of the door whether inward or outward will be sufiicient to dislodge thimble 28, as shown in Figure 2, from its position on the end of either of the arms. Furthermore it will be noticed that in case wire or thread 30 is broken or disconnected from bracket 33 the tension of spring 18 will cause the arms to rotate and the thimble will be thrown off the arm on which it was placed and the alarm will be given. In addition to this, it will also be understood that should the door be shaken, to any considerable extent, the thimble will likewise be dislodged from the arm on which it is placed and the arms allowed to rotate and give the signal.

Where it is desired to wind the spring and leave the case and arms in wound condition but not in set condi tion the latch 24 may be swung up to the latched position, as shown by dotted outline in Figure 3. The arms and case 5 will then be securely held from unwinding spring 18. In this condition the thimble is of course not used and it may be allowed to hang from bracket 33 or attached to any convenient hook or peg on the door 32.

As hereinabove described the case together with the radially extending arms 7 and 8 with their appending clappers may be termed a spring energized rotary member. It is noted that the rotary member is journaled on base 2 so that the clappers of the rotary member contact the gong 21. Obviously any type of bell or other noise-making device may be substituted for the gong shown.

I claim:

1. A prowler alarm for installatiotn on door frames including doors, composed of a base mounted on said door frame, a gong attached thereto, a shaft extending outwardly therefrom, a case journaled on said shaft having radially extending arms carrying clappers disposed to strike said gong when said case is rotated, a spiral spring having its inner end attached to said shaft and its outer end attached to said case operating between said shaft and said case, a thimble having a recess fitting loosely over the ends of one of said arms carrying a fine flexible substantially tangentially extending wire attached to the door detaining said arm on which said thimble is fitted and case from rotating, and releasing said arm and case for rotation when said wire is pulled, by movement of said door.

2. A prowler alarm for installation on door frames including doors, composed of a base mounted on said door frame, a gong attached thereto, a shaft extending outwardly therefrom, a case journaled on said shaft having radially extending arms carrying clappers disposed to strike said gong when said case is rotated, a spiral spring having its inner end attached to said shaft and its outer end attached to said case operating between said shaft and said case, a thimble having a recess fitting loosely over the ends of any one of said arms carrying a fine flexible substantially tangentially extending wire attached to said door detaining the arm on which said thimble is fitted and case from rotating, and releasing said arm and case for rotation when said wire is pulled, by movement of said door, and a catch pivotally attached to said base and manually movable to a position engaging any one of said arms to detain it from rotation, and movable to an unengaged position releasing said radially extending arms for free rotaliOD.

3. A prowler alarm including a base for attaching to a portion of a building, .a gong attached to said base, a stationary's'haftextending outward from said base, a cupshapedcase h'a'ving'a circlilar'bottom and a rim extending toward said 'al'armbase 'journ'alled onsafd shaft having radial arms, carrying clappers on flexible .istems disposed to st'rikesaid gong when said case isrotated, a spiral spring within the rim of saidcasehaving an inner end attached to said shaft'and an cuteriend 'attachedto said case rim and operating between said shaft and said case, and adapted to be Wound'by rotation of said case and to rotate said case when 'released from said winding, a movable latch for detaining said casefrom rotation'by said spring wlren'wou'nd, 'and athimbleloosely fitting over the end of any one of said arms provided with a securing thread for attachment to a part of saidbuilding, and extending substantially tangentially from said case, so that said thimble and thread will normally detain the arm on which said thimble is fitted and said case from rotation and will release the arm on which said thimble is fitted when disturbed.

References Citedin the file of this patent UNITED STATES PATENTS 314,450 Jacobi Mar. 24, 1885 556,208 Quick Mar. 10, 1896 2,600,609 Barton June 17, 1952 2,614,519 Paladino Oct. 21, 1952

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