US2179042A - Burglar-alarm window guard - Google Patents

Description

Nov. 7, 1939.

H. JACKSON BURGLAR-ALARM WINDOW GUARD Filed Nov. 29, 1937 3 Sheets-Sheet 1 a' myfwm@ ATTORNEYS NOV. 7, 1939. H, JACKSON l 2,179,042

BURGLAR-ALARM WINDOW GUARD Filed Nov. 29, 1937 3 Sheets-Sheet 2 m v lNvENToR i ATTORNEYS Nov. 7, 1939- H. JACKSON BURGLAR-ALARM WINDOW GUARD C5 Sheets-Sheet 5 Filed NOV. 29, 1957 ffl!! l Patented Nov. 7, 1939 UNITED STATES PATENT oFFicE 3 Claims.

This invention relates to burglar alarm window guards of that general type adapted to protect window, door and other openings.

An object of the invention is to provide a lazy tong closure having novel joints for effectively mounting the alarm trip cable within the interior of certain hollow bars of the lazy tong.

A further object is to provide novel switches adapted to be tripped when a surreptitious attempt is made to sever the bars of the lazy tong.

A further object is to provide a lazy tong burglar alarm guard which will be formed of a few strong simple and durable parts, which will be inexpensive to manufacture and which will not easily get out of order.

With the above and other objects in view the invention consists of certain novel details of construction and combinations of parts hereinafter fully described and claimed, it being understood that various modications may be resorted to within the scope of the appended claims without departing from the spirit or sacricing any ofthe advantages of the invention.

In the accompanying drawings forming part of this specification,

Figure 1 isa front elevation with parts in section, of a lazy tong burglar alarm guard constructed in accordance with the invention, in extended position.

Figure 2 is a fragmentary front elevation showing one-half rof the lazy tong structure, shown in Figure l, in collapsed or retracted position.

f Figure 3 is a detail enlarged sectional View taken on the line 3-3 of Figure 2 showing one of the joints and the trip cable and pulley.

Figure 4 is a longitudinal sectional view taken on the line 4-4 of Figure 3.

Figure 5 is an enlarged cross sectional View taken on the line 5-5 of Figure 2 showing alternate flat and hollow bars forming the lazy tong.

Figure 6 is an enlarged cross sectional view taken on the line 6 6 of Figure 2 showing a pivotal connection between a hollow bar and a at bar.

Figure 7 is an enlarged longitudinal sectional View taken on the line I 'l of Figure 1 and showing the switch and burglar trip cable carried by one of the joints at a bottom mounting hinge of the lazy tong.

Figure 8 is a detail longitudinal sectional View taken on the line 8 8 of Figure '7.

Figure 9 is an enlarged detail sectional View taken on the line 9-9 of Figure 1 and showing the yieldable catch for holding the lazy tong eX- tended.

Figure 10 is an enlarged detail sectional View taken on the line IU-I of Figure 1 showing the means for securing one end of the trip cable.

Figure 11 is a longitudinal sectional View taken on the line II--ll of Figure 10.

(Cl. 20D-52) Figure 12 is an enlarged longitudinal sectional i View taken on the line l2-I2 of Figure 1 showing one of the hinges of the lazy tong.

Figure 13 is an enlarged detail sectional View taken on the line lS-IS of Figure l and showing the top hinge to which a padlock may be secured.

Figure 14 is a longitudinal sectional View taken on the line lt-ili of Figure 13.

Figure 15 is an enlarged longitudinal sectional view taken on the line IE5- I5 of Figure l and showing the vertical end bar at the free end or" one section of the lazy tong.

In all forms of the invention the alarm circuit may be closed by tampering with the lazy tong such as for instance when rattling the two secn tions. The current is not being used until such tampering closes the alarm circuit, or until surreptitious severing of a concealed switch trap cable is accomplished. Furthermore, the lazy tong may be formed with alternate bars respectively tubular and lat so that the tubular bars which carry the trip cable are in parallel planes and must be connected together by a novel type of joint.

Referring now to the drawings in which like characters of reference designate similar parts in the various views, I designates a closure to be protected, ior example a window. In carrying out the invention a novel lazy tong is utilized as a guard, the same comprising two sections desig nated in general by the numeral Il. Each section is secLued at one end to a respective anchor bar l2. Each anchor bar is hinged to a respective base plate i3 which is secured to the side of the sash by screws i4, as shown in Figure 12, or other connectors. The free end of each section terminates in a respective vertically dis posed bar i5 which is provided with a grip it for extending and collapsing the section.

In the embodiment of the invention shown in Figure 1 each section of the lazy tong is formed of alternate tubular and flat bars il and 1G respectively, the tubular bars being disposed in parallel planes, as best shown in Figure 5. As also shown in Figure 5 each flat bar is pivotally connected at the center to the center of the tubular bar which crosses it, by means of a pivot bolt l-l which is swivelly mounted on the ilat bar and is provided with a fork 2B which embraces the tribu-- lar bar.

As best shown in Figures 3 and 4, the tubular bars form hosuings for a switch trip cable 2l. The cable is trained over sheaves 22. Each sheave is mounted on a shaft 23, which is journaled in a channeled ring 24 that connects the flattened ends 25 and 2B of two caps 21 and 28 carried by the meeting outer ends of each pair of tubular bars. The ring may be Xed to the flattened end 26 by a pin 28 and the flattened end 25 may swivel in the ring to form a pivot. A spacing Washer 29 may be interposed between the flattened ends 25 and 26. Removable closures 30 and 3l close openings in the sides of the flattened ends 25 and 2B, said openings permitting assembly of the parts.

As best shown in Figure 6 the meeting outer ends of the hat bars of the lazy tong are pivotally connected together by a pivot pin 32 passed through the bars. A spacing washer 33 is disposed on the pivot pin between the bars.

As best shown in Figures 1, l0 and ll the trip cable ZI is terminally anchored to a plug 34 disposed in the lower end of the iinal tubular bar of the series. The end of this bar is provided with a hinge eye 35 which is received between hinge eyes 35 projecting from the bar I5 at the free end of the lazy tong section. A pivot pin 31 is passed through the aligned hinge eyes.

As best shown in Figures 1, 'l and 8 the opposite end of the trip cable is secured to a stem 38 which is slidably mounted in disc guides 39 disposed in the end of the tubular bar I1 which begins the series of tubular bars of the lazy tong. A helical spring 4B is sleeved on the stem and bears against one of the guides and against a collar 4I on the stern` to hold the cable taut. The free end of the stem is formed of insulating material 2 which carries a conical switch contact 43.

When the cable 2| is severed the spring 40 expands and moves. the switch contact 43 to circuit closing position between diverging fingers 44 of a stationary switch contact 45, best shown in Figure 8. The stationary contact is in the form oi a ring which is seated upon a pivot pin 46 which is passed through openings in a hinge eye 4l which closes the end of the tubular bar and which is received between hinge eyes 48 carried by the anchor bar I2, as best shown in Figure 1.

The stationary contact is insulated from the pivot pin and hinge eye respectively by an insulating bushing 49 and a U-shaped bushing 50. Alarm circuit wires 5I and 52, best shown in Figure 8, are connected respectively to the movable switch contact 43 and stationary switch contact 45. v

As best shown in Figures l, 12, 13 and 14, each section ci the lazy tong is hinged on its respective anchor plate I3 so as to be swung out of the way when not in use, as is customary. For this purpose the anchor plate I3 is provided at spaced points with ears 53 having upstanding hinge pintles 54 to receive hinge eyes 55 carried by the bar l2 which supports the lazy tong section.

As best shown in Figures 1, 10 and 14 the uppermost hinge eye 55 is provided with an integral cap 55 in which the uppermost pintle is received. Aligned openings 5l and 58 are formed in the cap and pintle respectively to receive a padlock 55, shown in Figures l and 2 for locking the lazy tong section in either extended or collapsed position.

The upper end of the initial flat bar is provided with a slot 5B, best shown in Figure 14 to permit the bar sliding on the pivot pin SI which secures the bar at the upper end to ears 62 that project from the plate l2. This slot permits folding or the lazy tong section to collapsed position without binding of the parts.

The vertical bars I5 at the free ends of the lazy tong sections are provided with orificed ears 63, best shown in Figure 1, to receive a padlock 64 for locking the sections in extended operative position. Said bars I5 are also provided with spring pressed latches 65 which are received in a keeper 66 imbedded in the sash Ill to yieldably hold the sections in extended position. In addition each section is provided with a gravity operated latch 6l slidably mounted on pins 68 carried by the final folding ilat bar I8 of the section. The latch is receivable in a keeper 69 countersunk in the bottom of the sash. The latches 65 and 5l hold the sections steady against rattling.

What is claimed is:

1. A burglar alarm comprising a lazy tong closure, said lazy tong including crossed bars pivotally connected at their crossing and pivotally connected at their ends, certain of the bars bcing tubular and arranged in such sequence as to form` a continuous passageway, pulleys disposed at the pivoted ends of the bars forming the passageway, a cable trained over said pulleys and secured at one end to the initial tubular bar iorm ing the passageway, a switch contact connected to the opposite end of the cable in the i'lnal bar forming said passageway, and a spring connected to the cable at said contact for maintaining the cable taut and for moving the contact to circuit closing position upon rupture of the cable.

2. A burglar alarm comprising a lazy tong closure, said lazy tong including crossed bars pivotally connected at their crossing and pivotally connected at their ends, certain of the bars be ing tubular and certain of the bars being hat, the tubular bars alternating with the flat bars, the tubular bars being in parallel rows, hollow pivotal connections at the meeting outer ends of the tubular bars forming with the tubular bars a continuous passageway, pulleys in said hollow pivotal connections disposed with their axes of rotation transversely of the hollow pivotal connections, a trip cable trained through said tubular bars and over said pulleys, means anchoring the cable at one end to the initial tubular bar of the lazy tong, a switch Contact connected to the opposite end of the cable in the nal tubular bar of the lazy tong, and a spring asembled with the contact for tensioning the cable and for moving the contact to circuit closing position when the cable is ruptured.

3. A burglar alarm comprising a lazy tong closure, said lazy tong including crossed bars pivotally connected at their crossing and pivotally connected at their ends, certain of the bars being tubular and the other bars being ilat, said tubular bars being arranged in front of the ilat bars to dispose the tubular bars in one row and the ilat bars in a parallel row therewith, links pivotally connecting the outer ends of adjacent tubular bars together, rollers carried by said links, a trip cable trained over said rollers between said links and extending uninterrupted through said tubular bars, means anchoring the cable at one end to one of the tubular bars, a circuit closer connected to the opposite end of the cable, and a spring connected to the cable for tensioning the cable and for moving the circuit closer to circuit closing position when the cable is ruptured.

HARRY JACKSON.

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