|Publication number||US3530262 A|
|Publication date||Sep 22, 1970|
|Filing date||Jan 25, 1968|
|Priority date||Jan 25, 1968|
|Also published as||DE1902838A1|
|Publication number||US 3530262 A, US 3530262A, US-A-3530262, US3530262 A, US3530262A|
|Inventors||Hawkins Paul Maddison|
|Original Assignee||Gen Alarm Corp|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (1), Referenced by (4), Classifications (11)|
|External Links: USPTO, USPTO Assignment, Espacenet|
Sept. 22, 1970 P. M. HAWKINS LOCK SWITCH DEVICES Filed Jan. 25, 1968 5 Sheets-Sheet l 1 INVENTOR.
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LOCK SWITCH DEVICES Filed Jan. 25, 1968 5 Sheets-Sheet 5 will!!!" 1 v V 1 .111 INVENTOR. /J T Q a W mp/50y Alywmvs United States Patent US. Cl. 20044 13 Claims ABSTRACT OF THE DISCLOSURE Lock-alarm device having anchor plate adaptable to be secured to closure member, a top secured to anchor plate but having relative movement therewith, and electrical alarm having a multiposition switch including spaced apart electrodes completed by a plunger rod.
This invention relates to lock alarm arrangements of the type which respond to jimmying or prying forces to signal an attempted unauthorized intrusion.
The general idea of a combination lock and alarm to produce a signal in response to jimmying forces has long been known. In the past, however, the actual use of such devices has been quite limited. This in part was due to the considerable expense and complexity of these devices. Perhaps even more important, however, was the fact that rather major structural changes had to be made to the room or other area being protected. For example, in some instances, special mortices had to be formed in doors, windows, and their frames to accommodate the locking arrangements.
The present invention is an improvement of the invention described and claimed in my copending application Ser. No. 623,023, filed Mar. 14, 1967. In the latter application there is disclosed an invention which eliminates the difficulties associated with the construction and installation of the apparatus of the class described. According to one aspect of that invention, I provide a lock alarm which includes an anchor plate constructed to be secured to a window or door without any major structural modifications thereto. That lock alarm also includes a top secured to the anchor plate in a manner allowing limited movement of the top up from the plate. A lock bolt is mounted within the top for carrying out the desired locking of the window or door; an electrical alarm generator and speaker are also provided in the top as is an electrical switch for actuating the alarm system, the latter being spring biased to an operational condition. A latch is provided to hold against this spring bias in order to maintain the alarm switch in an inoperative condition. This latch is releasable when the top is partially lifted up from the anchor plate; this latter effect occurring when a window or door member secured by the lock bolt is jolted.
The spring biased switch of the mentioned copending application includes a battery clip constructed to contain one or more batteries for providing electrical power to the alarm system. The positive terminal of the battery is maintained in permanent contact with the alarm system. The negative or ground connection of the battery is connected to the alarm system through the top which is constructed of metal. When the spring biased switch, includ ing the battery clip is held by the latch in the manner noted above, the negative terminal of the battery is held in an open condition away from the top. When the latch is released by the movement of the top, the spring biased battery clip moves forward and is brought into direct contact with the metal top thereby bringing the negative end of the battery into electrical contact with the top and actuating the electrical alarm.
The present invention is directed to a lock alarm device 3,530,262 Patented Sept. 22, 1970 which is similar in some respects to the lock alarm of my copending application discussed above, but includes a novel top as well as a novel electrical switch for actuating the alarm, both of which cooperate to provide an alternate solution to the same problems solved by the aforementioned invention.
ln accordance with one aspect of the present invention, there is provided an anchor plate constructed to be secured to a closure member in a manner similar to that of my copending application. A novel top for the anchor plate is provided which is secured to the anchor plate in a manner allowing limited relative movement therebetween. This top includes means to house the electronic alarm generator and speaker as well as to fixedly mount the batteries which energize the alarm generator. A multiposition alarm switch is provided for completing a serial electrical connection between the electronic alarm generator and its source of power, the batteries; the switch includes spaced-apart switch contacts mounted within the top and serially connecting the alarm generator and the batteries. A plunger rod is also provided within the top near the switch contacts; the rod has a depending latch tab at one end and an electrically insulative surface laterally spaced from an electrically conductive surface at the other end. The end of the plunger rod, which has the electrically conductive and insulative surfaces, is snugly but slidably mounted between the spaced-apart switch contacts such that when shifted to a first position, the electrically conductive surface simultaneously contacts each of the switch contacts, thereby completing the serial connection between the electronic alarm generator and the batteries and thus actuating the alarm; and when shifted to a second position, the electrically insulative surface portion simultaneously contacts each of the switch contacts thereby opening the serial connection and deactivating the alarm.
The top not only is provided with a locking bolt which functions in a manner similar to that of my aforementioned invention, but also is provided with a resilient bias means for urging the plunger rod containing the depending latch tab to the first position. The anchor plate of the present invention includes an upstanding latch adaptable to engage the depending latch tab of the plunger rod and is positioned on the top surface of the anchor plate so as to engage the depending tab of the rod and to hold against the urging of the resilient bias and maintain the rod in the second position.
When the closure member is pried or jimrnied, the locking bolt tilts the top a slight degree from the anchor plate and thereby causes the plunger rod to be raised up off the latch. As a result, the resilient biasing arrangement causes the plunger rod to move to the mentioned first position and thereby complete the series circuit between the electronic alarm generator and the batteries, and thus causes the production of an acoustical alarm via a speaker housed in the top.
According to another aspect of the present invention, there is provided novel cooperation between the top and the anchor plate. In the present invention the top includes an inner member which houses the electrical alarm system including its power source, the mentioned spaced-apart switch contacts, and the mentioned plunger rod, and an outer cover having a plug bore at one far end for housing the locking bolt and having an upwardly extending cavity in its remaining volume. The cavity is adapted to snugly enclose and surround the inner member. The anchor plate includes an upstanding flange at one end and a horizontally extending fixedly mounted leaf spring at the other end.
The inner member housing the electronic alarm system and .rod is placed over the anchor plate so that the plunger rod is operably engageable with the upstanding latch.
The outer cover housing the locking bolt is placed over the inner member and fixedly mounted at one end to the upstanding flange of anchor plate and at the other end to the horizontally extending leaf spring. The inner member, while not mechanically coupled to either the anchor plate or the outer covering, is responsive to movements of the outer cover since it is captivated in the shell or cavity thereof.
The top cooperates to provide a tam-perproof arrangement. Thus, since the anchor plate is completely covered by the outer cover, the bolts or screws mounting it to the closure member are completely inaccessible. Moreover, since the plunger rod is fixedly mounted in the inner member and biased to its alarm actuation position, any attempt to remove the outer cover from the anchor plate will result in the actuation of the alarm.
In accordance with another aspect of the present invention, the lock alarm is provided with a reset function. This is achieved by the provision of a notch recess having a tapered cam surface in the middle of the lateral side of the locking plug containing the locking bolt; the end of the plunger rod having the depending latch tab, fits perpendicularly into this recess when the rod is in its first or alarm actuating position. When the locking plug is retracted to an unlocked position, the cam surface of the recess acts upon the rod and urges it to the first position Where it is engaged by the latch extending up from the anchor plate. Thus, the lock alarm is readied for alarm actuation again.
There has thus been outlined rather broadly the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject of the claims appended hereto. Those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures for carrying out the several purposes of the invention. It is important, therefore, that the claims be regarded as including such equivalent constructions as do not depart from the spirit and scope of the invention.
Specific embodiments of the invention have been chosen for purposes of illustration and description, and are shown in the accompanying drawings forming a part of the specification wherein:
FIG. 1 is a perspective view illustrating a window arrangement incorporating the lock alarm of the present in- Mention;
FIG. 2 is an exploded view of the lock alarm of FIG. 1;
FIG. 3 is an enlarged fragmentary perspective showing the cooperation of the plug bore and locking plug of the lock alarm of FIG. 1;
FIG. 4 is a section view taken along line 4-4 of FIG. 1 showing the internal switch configuration;
FIG. 5 is a front view, partially broken away of the lock arm of FIG. 1;
FIG. 6 is a section view taken along line 66 of FIG. 1 showing the electrical switch arrangement in protracted or triggered condition;
FIG. 7 is a section view also taken along line 66 of FIG. 1 but showing the switch arrangement in its alarm actuating condition;
FIG. 8 is a side view, partially broken away, of the lock alarm of FIG. 1;
FIG. 9 is also a side view, partially broken away, of the lock alarm of FIG. 1 when the window is subject to prying or jimmying action;
FIG. 10 is a perspective view illustrating a door arrangement incorporating the lock alarm of the present invention;
FIG. 11 is an enlarged fragmentary view, partially broken away, showing the cooperation of the locking plug and the door striker plate; and
FIG. 12 is a section view taken along line 1212 of FIG. 11.
Referring now to the drawings in detail, and more specifically to FIG. 1, there is shown a window installation arrangement incorporating the lock alarm of the present invention. Thus, a lock alarm unit depicted generally at 20 is mounted on the top surface 21 of a lower window sash 22 in close positional relationship to a slide or edging member 24 of an upper window sash 26. The lock alarm unit 20 includes an anchor plate 28, which is fastened to the lower sash 22, and a top 30, which fits over the anchor plate 28. Toward one end of the top 30, there is provided a horizontally extending plug bore 32 which houses a locking plug 34. Toward the other end of the top 30, but on the roof thereof, grill structure 36 is provided to allow acoustical output from the locally generated alarm within the top 30. As shown in FIGS. 1 and 4-9, the anchor plate 28 and the top 30, are dimensioned so that When they are nested together, their outer surfaces are contiguous so as to provide the appearance of a single compact .rectangular block which may neatly fit on the top surface 21 of the lower sash 22. Of course, top may include other features and designs which will render the lock alarm 20 esthetically pleasing and less conspicuous when in place.
The exploded view provided in FIG. 2 shows in greater detail the general construction of the lock alarm unit 20. The lock alarm device 20 is essentially made up of the anchor plate 28, a top 30 having an inner member 38 and outer cover 39, a plunger rod 40, and a spring 41.
The anchor plate 28 is generally rectangularly shaped and includes an integrally formed upstanding section 42 which defines both lip structure 44 along a substantial portion of the outer peripheral edges of the anchor plate 28, as well as recess 46 in some surface portions of anchor plate 28. Lip structure 44 cooperates with the depending walls of the outer cover 39 so that the side surfaces of both the anchor plate 28 and the outer cover 39 form substantially a continuous surface and so that each of said members are laterally fixed in relation to each other. Recess 46 functions in part to provide an area to partially house the batteries 74 which depend from the inner member 38 and thereby provides a snug and compact fit between the interface surfaces of the anchor plate 28 and the inner member 38. An L-shaped flange 48 having a threaded bore 50, is provided on upstanding section 42 at one end of the anchor plate 28; flange 48 is preferably recessed and fastened to section 42 by rivet 52 in a well-known manner. A latch 54 extends up from the bottom surface of anchor plate 28 and is securely fastened to leaf spring 56 which is recessed in the bottom surface of anchor plate 28 and secured thereto by rivet 58. The latch 54 is part of a multiposition switch mechanism to be described hereinafter. A rectangularly-shaped leaf spring 60 is also secured on the top surface of the anchor plate 28 near the end opposite flange member 48 by rivet 62 and wedge 64.
As shown in FIG. 2, anchor plate 28 also includes mounting holes 66ad through which screws or bolts 68 ad may pass to secure the anchor plate 28 against the top surface 21 of the window frame 22.
The inner member 38 of the top 30 has a generally rectangularly-shaped outer configuration except for recesses 70 and 72 which are defined by the integrally formed wall 76. A battery clip 77 is provided on the remaining two but oppositely facing side walls defining recesses 70 and 72 to hold and provide a buss electrode for the batteries 74. The Wall 76 has a keyhole-shaped slot 78 extending horizontally therethrough as well as an oblong bore 79 which extends lengthwise in the wall from the side of the inner member 38 (FIG. 5). Bores 80 and 82 are countersunk in the bore 79. The bore 80 extends parallel to the wall 76 from the bottom of the oblong bore 79 to the keyhole-shaped slot 78, and bore 82 also extends parallel to the wall 76 but directly below the bore 80 and terminates with dead end in the wall 76.
A horizontally projecting switch contact 90 extends from a battery buss 77 in each of the recesses 70 and 72 to the keyhole-shaped slot 78; each of the contacts 90 includes a V-shaped portion 91 which extends into the slot 78 and thus forms therein a pair of centrally located spaced-apart contacts. The contacts 90 complete a serial connection with the electronic alarm generator 86 and the batteries 74 and are part of a multiposition switch mechanism to be more particularly described hereinafter.
As shown in FIGS. 2 and 4., inner member 38 also includes portion 84 defining a hollow 85 which extends up from the bottom surface and which houses the electronic alarm generator 86 and the speaker 87. Portion 84 also includes a rectangularly cut slot 88 extending up from the bottom and from one side thereof through to the hollow 85.
As best shown in FIG. 2, plunger rod 40 has a depending latch tab 92 at one end, and at the other end, an electrically insulative surface 94 laterally spaced from an electrically conductive surface 96. In the preferred embodiment, the desired laterally-spaced insulative and conductive surfaces are provided by forming the end of the rod 40 of an electrically conductive metal and applying an electrically insulative material circumferentially about a selected portion thereof. Obviously, other methods may be utilized.
The end of the plunger rod 40 having the electrically conductive and insulative portions is adaptable to snugly but slidably fit between the V-shaped portions 91 of the spaced-apart contacts 90 such that when slid in a first position, the electrically conductive surface portion simultaneously contacts each of the contacts 90 and completes an electrical path therebetween, and when slid in a second position, the electrically insulative surface portion simultaneously contacts each of the contacts and opens the electrical path therebetween. Plunger rod 40 is also part of the multiposition switch mechanism to be described hereinafter.
As shown in FIGS. 2 and 4, outer cover 39 is shaped like an inverted rectangular box except for solid portion 98. The solid portion 98 is provided with a plug bore 32 extending from one side of the outer cover 39 to the other and adaptable to receive a plug 34 having a locking bolt 100. As best shown in FIG. 3, the bottom portion of the plug bore 32 is provided with two slots 102, each extending inwardly from a side of the outer cover 39. A small guide screw 104 passes through the slot 102 and is threaded into the plug 34. The head of the guide screw 104 thus moves back and forth along the slot 102 as the plug 34 moves back and forth within its bore 32. It will be appreciated that the guide screw 104 thus limits both the rotational as well as longitudinal movement which the plug 34 may undergo within the housing 98. As shown in FIGS. 2, 8 and 9, outer cover 39 also includes two inwardly projecting flanges 105 which extend horizontally from opposite sides of the outer cover 39 at points directly below the solid portion 98. The function of the flanges will become more apparent hereinafter.
Returning to FIG. 3, it will be seen that the locking plug 34 includes a cylinder lock 106 having a depending latch member 108 which is adaptable to engage slot 110 provided in the outer cover 39, a projecting locking bolt 100, and notched recesses 112 each having a tapered cam surface 114.
The above described parts are assembled as follows. First, the anchor member 28 is mounted on the top surface 21 of sash 22 by the screws 68ad. Next inner member 38, having plunger rod 40 and spring 41 inserted in the countersunk bores 80 and 82, is placed directly over and above the anchor plate 28 with its slot 87 surrounding the flange 48 extending upwardly from the anchor plate and with the plunger rod engageable with the latch 54 also extending upwardly from the anchor plate. The outer cover 39 is then placed directly over the inner member 38 with its solid portion 98 fitting over and aligning behind the side wall of the inner member at the end provided with the bores and 82. The outer cover 39 is then fastened at one end to the flange 48 of anchor plate 28 by a bolt 116 through an opening 118 provided in the outer cover 39. At the other end, leaf spring 60 which is fixedly mounted to the anchor plate engages and rests upon the upper surfaces of the flange members 105 extending horizontally from the outer cover and thus secures the outer cover 39 to the anchor plate 28 in a manner allowing limited relative movement therebetween. Thus, it will also be seen that the inner member 38 is captivated and controlled by the outer cover 39 while at the same time also is subject to some relative movement with the anchor plate.
As pointed out above, spaced-apart switch contacts 90, plunger rod 40, spring 41 and the latch tab 54 cooperate to provide a multiposition switch mechanism for activating the electronic alarm system. The operation of this multiposition switch is diagrammatically shown in FIGS. 4-9.
As clearly shown in FIGS. 5 and 7, spring 41 biases the plunger rod 40 to slide it to a first position such that its electrically conductive surface portion 96 simultaneously contacts the V-shaped portions 91 of the spacedapart contacts and thus completes the electrical path beween the contacts thereby actuating the electronic alarm. Latch tab 54 is positioned on the surface of the anchor plate 28 so as to engage the depending tab 92 of the rod 40 and to hold against the bias of the spring 41 and maintain the rod 40 in a second or triggered position. This cooperation is clearly shown in FIGS. 4 and 6. The rod 40, when held in this second or triggered position, is positioned such that its electrically insulative surface portion 94 simultaneously contacts the V-shaped portions 91 of the contacts 90 and thus maintains open the serial electrical path through contacts 90 and between the electrical alarm generator 86 and its energizing source.
The multiposition switch mechanism operates in the following manner. Lock alarm 20 is maintained on the top surface 21 of the lower sash member 22 in its triggered position with the locking bolt 34 engaged in a bolt receiving recess 120 so as to effectively lock the upper and lower sashes 22 and 26 together. Outer cover 39 is responsive through the locking bolt 34 to prying or jimmying force applied to the sashes 22 and 26 and is raised up from the anchor plate 28 and latch 54. As a result, the biasing arrangement produced by the spring 41 causes the rod 40 to move forward to its first position and thereby activate the alarm system in the manner explained above.
While the action of the locking plug 34 and the locking bolt function to lock the closure members 22 and 26, locking plug 34 additionally provides a reset function. This is achieved by the provision of the notches 112 having tapered cam surfaces 114 toward the bolt end thereof. As shown in FIGS. 5 and 7, the rod 40 and its depending flange 92 fit into one of the recesses 112 when the rod 40 is moved forward by the biasing spring 41. When the locking plug 34 is retraced, however, to an unlocked position, as shown in FIGS. 4 and 6, the cam surface 114 of the notch 112 acts upon the rod 40 urging the same back to a position beyond the latch 54. When the plunger rod 40 reaches this position, then the latch 54 under the influence of its lever arm 56 will move upwardly to latch the depending tab 92 of the rod 40 and thereby restore the rod to its first or triggered condition. Thereafter, the window sashes 22 and 26 are again locked together by pushing inwardly the locking plug 34 to cause the bolt 100 to project into the bolt recess and the lock alarm is again positioned for alarm actuation.
While the above describes the lock alarm unit 20in a window arrangement, it should be appreciated that this device may be utilized in other closure arrangements. Thus, for example, as shown in FIGS. 12, the unit may be mounted on the door 210 and engage the striker plate 212 mounted on the side trim 214 adjacent to the door with a locking bolt 216, preferably longer than the locking bolt 34 utilized in the window arrangement described above. The locking bolt 216 cooperates with the lock alarm in substantially a manner similar to locking bolt 34.
Thus, it will be seen from the above that the lock alarm of the present invention eliminates the dilficulties associated with the construction and installation of many lock alarms in the past. These difiiculties are overcome by the provision of a novel anchor plate and top therefor which provides a relatively tamperproof arrangement and by the operation and cooperation of a multiposition alarm actuating switch.
Having thus described my invention with particular reference to the preferred forms thereof, it will be obvious to those skilled in the art to which the invention pertains, after understanding my invention, that various changes and modifications may be made therein without departing from the scope and spirit of my invention, as defined by the claims appended thereto.
What is claimed as new and desired to be secured by letters patent is:
1. A lock-alarm device comprising an anchor plate constructed to be secured to a closure member, a top for said anchor plate, means securing said top to said anchor plate in a manner allowing limited relative movement therebetween, said securing means including Spring means arranged to resist such movement, electrical alarm means, a multiposition electrical switch cooperable with said anchor plate and top therefor for actuating said electrical alarm means, said switch including spaced-apart switch contacts serially connected to said electrical alarm means and plunger rod means simultaneously contacting each of said switch contacts, said plunger rod completing an electrical circuit between said switch contacts when in a first position and, maintaining an open circuit therebetween when in a second position, resilient bias means for urging said rod to said first position, and latch means for holding against the urging of said resilient bias means to maintain said rod in said second position, said latch means being releasable upon the relative movement of said top and said anchor plate.
2. The lock-alarm device as in claim 1 wherein said rod has an insulative portion laterally spaced from an electrically conductive portion.
3. The lock-alarm device as in claim 1 wherein said rod has a depending latch tab cooperable with said latch means ,at one end and an electrically insulative portion laterally spaced from an electrically conductive portion at the other end.
4. The lock-alarm device as in claim 1 wherein the top is configured to substantially cover said anchor plate means.
5. The lock-alarm device as in claim 1 wherein said switch contacts complete a series connection between an electronic alarm generator and a power source.
S 6. The lock-alarm device as in claim 1 wherein said top includes an inner member housing said multiposition switch and an outer cover enclosing and captivating said inner member.
7. A lock-alarm device comprising an anchor plate constructed to be secured to a closure member, a top therefor for said anchor plate means securing said anchor plate, means securing said top to said anchor plate in a manner allowing limited relative movement therebetween, said securing means including spring means arranged to resist said movement, a locking bolt mounted in said top for moving between retracted and projected positions, said locking bolt constructed to engage with another closure member, electrical alarm means carried by said top, a multiposition electrical switch for actuating said electrical alarm means, said switch including spaced-apart switch contacts serially connected to said electrical alarm means and a plunger rod simultaneously contacting each of said switch contacts, said plunger rod completing an electrical circuit between said switch contacts when in a first position and maintaining an open circuit therebetween when in a second position; resilient bias means carried by said top for urging said rod to said first position, and latch means secured to said anchor plate for holding against the urging of said resilient bias means to maintain said rod in said second position while said top rests against the anchor plate, and to release said rod when said top undergoes said relative movement.
8. A lock-alarm device as in claim 7 wherein said top is configured to substantially fully cover said anchor plate when it is in place on said anchor plate.
9. A lock-alarm device as in claim 7 wherein said locking bolt is provided with cam means engageable with said plunger rod to retract said plunger rod to said second position and to efiect re-engagement of said latching means upon retraction of said locking bolt.
10. The lock-alarm device as in claim 7 wherein said rod has an insulative portion laterally spaced from an electrically conductive portion.
11. The lock-alarm device as in claim 7 wherein said rod has a depending latch tab cooperable with said latch means at one end and an electrically insulative portion laterally spaced from an electrically conductive portion at the other end.
12. The lock-alarm device as in claim 7 wherein said switch contacts complete a series connection between an electronic alarm generator and a power source.
13. The lock-alarm device as in claim 7 wherein said top includes an inner member housing said multiposition switch and an outer cover enclosing and captivating said inner member.
References Cited UNITED STATES PATENTS 2,756,300 7/1956 Thiberville 20061.67
ROBERT K. SCHAEFER, Primary Examiner H. J. HOHAUSER, Assistant Examiner U.S. Cl. X.R.
-90; ZOO-61.67, 61.81; 340-274
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US2756300 *||Nov 30, 1953||Jul 24, 1956||Thiberville Arthur J||Lock controlled switch|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US3755802 *||Sep 30, 1971||Aug 28, 1973||Stanley Works||Alarm bolt|
|US4024526 *||May 19, 1976||May 17, 1977||Joseph Banner||Alarm device for use in combination with window sash|
|US4283718 *||Jul 2, 1979||Aug 11, 1981||Synco National Ltd.||Door alarm device|
|US5311168 *||Sep 10, 1992||May 10, 1994||Pease Industries, Inc.||Lock set with self-contained door alarm and annunciator system|
|U.S. Classification||200/43.8, 200/61.81, 70/90, 340/542, 200/61.67, 340/693.9|
|International Classification||E05B45/00, E05B45/14, E05B45/06|