US3759557A

US3759557A - Locking bars for high security padlocks

Info

Publication number: US3759557A
Application number: US00146711A
Authority: US
Inventors: S Athas
Original assignee: US Department of Army
Current assignee: US Department of Army
Priority date: 1971-05-25
Filing date: 1971-05-25
Publication date: 1973-09-18
Anticipated expiration: 1990-09-18

Abstract

The invention relates to locking bars for use with a type of high security which includes a recess therein to accommodate the shackle and a transverse recess adapted to accommodate part of the locking bars when the shackle is in locking position on the locking bars. The invention comprises providing the locking bars with one or more abutments which serve to prevent improper mounting of the padlock on the locking bars, to prevent swinging of the padlock in relation to the locking bars and to provide support for the padlock during attempts to defeat the padlock by force.

Description

[ Sept. I8, 1973 LOCKING BARS FOR HIGH SECURITY PADLOCKS [75] Inventor: Stanley T. Athas, Lowell, Middlesex,

, Mass.

[73] Assignee: The United States of America as represented by the Secretary of the Army, Washington, DC.

[22] Filed: May 25, I971 [21] Appl.vNo.: 146,711

[52] US. Cl. 292/281, 70/54 [51] Int. Cl. E05c 19/08 [58] Field of Search 70/54, 55, 56, 51, 70/52; 292/281-286 [56] 5 References Cited UNITED STATES PATENTS 3,652,114 3/1972 Cady et al 70/56 X 3,572,064 3/1971 Berry 292/281 FOREIGN PATENTS OR APPLICATIONS 537,560 5/1955 Belgium 292/281 Primary Examiner-Richard E. Moore Attorney-Harry M. Sargovitz, Edward J. Kelly, Herbert Berl and Charles F. Murphy [57] ABSTRACT The invention relates to locking bars for use with a type of high security which includes a recess therein to accommodate the shackle and a transverse recess adapted to accommodate part of the locking bars when the shackle is in locking position on the locking bars. The invention comprises providing the locking bars with one or more abutments which serve to prevent improper mounting of the padlock on the locking bars, to prevent swinging of the padlock in relation to the locking bars and to provide support for the padlock during attempts to defeat the padlock by force.

6 Claims, 3 Drawing Figures PATENTEB SEN 8W8 SHEET 2 BF 2 leave/22 302 5 Tflifzms, av my BACKGROUND OF THE INVENTION The present invention relates to locking bars for use with a particular type of high security padlock of the kind that includes a U-shape shackle which is received in borings or recesses provided in the top of the padlock body which incorporates a locking mechanism for locking the shackle in its closed position and wherein the padlock body is so configurated as to hinder attack on the shackle when it is in the locked position. This type of padlock afiords a very high degree ofv security by further providing a transverse recess in the body thereof to accommodate portions of locking bars which are fixed to and extend from the surface of a door or other item to be secured and by locating the openings in the locking bars which are intended to receive the shackle of the padlock in the portions of the locking bars which are adapted to be received in the transverse recess in the body of the padlock. The combined effect of these features results in the shackle of the padlock being virtually completely protected from attack by saws, chisels and the like by the padlock body and the locking bars.

The present invention is particularly adapted for use with a padlock of the type described wherein thetransverse recess which is adapted to receive a portion of the locking bars is closed at one end by a portion of the padlock body. In the typical application of this type of padlock, the locking bars extend outwardly of a vertical surface such as a door or the like and the padlock is mounted thereon in a vertical plane. One of the primary methods of attacking a padlock of this type is by attempting to defeat the locking mechanism which is accessible at the bottom of the padlock body where the key slot is located. Such attempts through the use of drills or the like are significantly impeded when the padlock is in the vertical plane because of its proximity to the adjacent surface of a door or other member to be secured. On the other hand, swinging of the padlock from the vertical plane toward or to the horizontal plane substantially aids in this type of attack by making the bottom of the padlock more accessible to tools. It is, therefore, a significant aspect of the degree of security afforded by this type of lock configuration to assure that the lock remains in a plane parallel to the adjacent surface of a door or other member being secured, i.e., in the vertical plane in the situation described above.

This contingency is dealt with on existing locking bars for use with this type of padlock by providing a configuration on the outer end of the locking bars which defines an abutment or beak extending from the end of the locking bars over the tip of the portion of the padlock body which forms the-closed end of the transverse recess therein when the latter is in the locked'position such that an attempt to swing the padlock away from the adjacent surface of a door or the like is prevented when that portion of the top of the padlock body comes in contact with the abutment on the end of thelocking bars. While this arrangement effectively prevents swinging of the padlock away from the adjacent surface, it depends for its effectiveness upon proper mounting of the padlock in the first instance. For example, through ignorance or neglect, the padlock can be mounted on the locking bars in a position substantially perpendicular to the surface of the door or the like being secured, thereby exposing the bottom of the padlock to unimpeded attack.

Another method of attack on this type of padlock involves the driving of a chisel or other tool down into the padlock body at the end of the locking bars. In this method, the ability of the padlock to be swung even to a limited extent toward the adjacent surface improves the effectiveness of the attack by providing better access to the closed end of the transverse recess in the padlock body.

While it is common practice in the art of high security locking devices to make maximum use of high strength materials and of various hardening treatments therefor, manufacturing cost is always a factor. In consideration of the various tools and devices available to attack such locking devices and in recognition of the fact that any type of lock known to the art can be defeated with the proper tools and enough time, the efiectiveness of such locking devices is determined in terms of the time required to defeat the locking device. For this reason, provision is made for the use of two padlocksin some applications since the time required to defeat two padlocks will inevitably be greater than the time required to defeat a single padlock.

SUMMARY OF THE INVENTION The present invention comprises an improvement in locking bars for use with the type of padlock described wherein the locking bars are provided with one or more abutments extending from the sides thereof and adapted to engage portions of the padlock body on either side of the transverse recess therein to prevent the padlock from being improperly mounted on the locking bars and to limit swinging movement of the padlock with respect to the locking bars when the padlock is in the locked position thereon.

It is, therefore, an object of this invention to improve the security effectiveness of the type of padlock described by providing locking bars which will prevent the padlock from being improperly mounted thereon and which will limit swinging movement of the padlock on the locking bars. Another object is to provide this improvement in the locking bars at minimal additional manufacturing and material cost.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded view showing a pair of locking bars in accordance with the present invention, a padlock shackle, a padlock body of the type intended to be used with the locking bars of the present invention and the padlock key. In the embodiment shown, provision is made for the placement of two padlocks on the locking bars.

FIG. 2 is a partial verticalsection showing the manner in which the locking bars of the present invention are mounted on a door or the like and showing a padlock of the type described, partially in section, mounted in locked position on the locking bars. A second padlock is shown in phantom mounted in locked position on the locking bars in the place provided therefor.

FIG. 3 is a front elevation of the locking bars of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1 of the drawing, the locking bars and 11 of the present invention comprise generally

flat plates

12 and 13, respectively, and include means on their inner ends for mounting the bars on the adjacent edges of a pair of doors or the like to be secured thereby, the

outer ends

14 and 15, respectively, of the locking bars extending substantially perpendicularly of the surfaces of the doors 16. The inner ends of the bars may, of course, be of other configurations appropriate to mounting the bars on the items to be secured. As best shown in FIG. 2, the inner ends of the locking bars are secured to the inside of the doors 16 or the like so that the mounting screws 17 are not accessible for.removal when the doors are locked. v

A high security padlock of the type intended for use, with the locking bars of the present invention comprises generally a shackle 18, a padlock body 19 and a key 20. As shown in FIG. 1, the top of the padlock body 19 is provided with a recess 21 adapted to receive the shackle 18 therein and a second recess 22 extending transversely of the shackle receiving recess 21 which is closed at one end by portion 23 of the padlock body. The padlock body 19 also houses conventional key operated locking means (not shown) for engaging and locking the shackle 18 in the recess 21 in the padlock bar. This locking means is operated by key 20 through a key slot (not shown) in the bottom of the padlock body in a conventional manner. The transverse recess 22 in the padlock body is generally rectangular in cross section and is closed at one end by a wall24 which is substantially perpendicular to the bottom 25 of the recess 22.

As best seen in FIG. 1, the recess 21 provided in the padlock body 19 to receive the shackle 18 intersects the transverse recess 22 and as best seen in FIG. 2 is sufficiently deep to receive the entire shackle within the padlock body in the locked condition.

In the embodiment shown, the outer ends 14 and of the locking bars are provided with two sets of aligned

openings

26 and 27, respectively, which are spaced respectively from the lower and

upper comers

28 and 29, respectively, of the outer ends of the locking bars as well as spaced a predetermined distance from each other for a purpose to be described. The thickness of the outer ends of the locking bars is selected to permit the lower an upper corners of the outer ends to be received in the transverse recess 22 of the type of padlock described to substantially fill this recess when the padlock is positioned on such lower or upper comers with the shackle 18 of the padlock through the respective aligned

openings

26 or 27 in the locking bars and locked in place in the padlock body 19. It is noted that in this position, proper spacing of the aligned

openings

26 and 27 in the locking bars in relation to the respective corners of the locking bars as shown in FIG. 2 will serve to substantially limit swinging movement of the padlock in relation to the locking bars due to the interaction of the

respective comers

28 and 29 of the locking bars and the end wall 24 and bottom wall 25 of the transverse recess 22 in the padlock body.

In order to prevent the padlock from being placed on the lower corners 28 ,of the locking bars in a horizontal position, rather than in the vertical position shown in FIG. 2, a small flap 30 is struck outwardly of the side of each locking bar at the outer end 31 thereof just above the portion of the locking bar which is received in transverse recess 22 of the padlock body 19. These flaps or offset portions 30 add to the width of the locking bars at this point as best seen in FIG. 3 such that the distance between the outer extremities of the offset portions 30 exceeds the width of the transverse recess 22 is the padlock body and provide an abutment which prevents the padlock body from being placed on the lower corners of the locking bars to the extent necessary to lockably engage the shackle 18. These same offset portions 30 will obviously also provide an abutment which will limit swinging movement of the padlock away from the surface of the door 16 by engaging the top surface of the padlock body on either side of the transverse recess 22.

A second set of opposed ofiset portions 32 is provided on the locking bars, struck from the lower edges 33 thereof and spaced inwardly of the lower comers 28 of the locking bars just beyond the portion thereof which is received in transverse recess 22 in the padlock body. These offset portions 32 are similary conformed to provide a total thickness of the locking bars at this point which is greater than the width of the transverse recess 22 in the padlock body and thereby provide abutment means to engage the edges of transverse recess on the sides of the padlock body to limit swinging movement padlock toward the surface of door 16 and to also provide support to the edges of the transverse recess which tends to prevent spreading of the recess and subsequent failure of the padlock body when the force of blows is applied to the padlock body during attempts to defeat the padlock.

As noted above, the embodiment of the invention shown in the drawing provides for the useof two padlocks which is desirable in certain high security applications. It will be readily apparent from FIG. 2 that the position of the second padlock 19' is somewhat inconsistent with the objects of the invention in that it is mounted in the horizontal position with respect to the surface of door 16 thereby exposing the bottom of the padlock body to convenient attack. However, despite this weakness, the presence of the second padlock will significantly add to the degree of protection attained since, although more easily attacked, the second padlock must be defeated before an attack may be made on the first padlock 19, thereby requiring additional time to defeat the combination.

The second. padlock 19' also has a proper position on the locking bars in that a vertical mounting on the upper comers of the locking bars would expose the key slot in the bottom of the second padlock to the elements and to contamination by dirt or other foreign materials. Accordingly, a third set of opposed offset portions 34 is provided in the upper edges 35 of the locking bars spaced from the upper comers 29 just beyond the portion thereof which is received in the transverse recess of the second padlock 19'. As with the offset portions previously described, offset portions 34 increase the effective width of the locking bars at this point to a distance greater than the width of the transverse recess of the second padlock to thereby provide abutment meanswhich prevent the body of the second padlock from engaging the upper comers 29 of the locking bars sufiiciently to lockably engage the shackle in openings 27 if an attempt is made to mount the padlock in the vertical position- Also, when the second padlock is properly positioned as shown in FIG. 2, cpposed ofiset portions 34 will engage the top of the body of the second padlock on either side of the transverse recess therein to limit swinging movement of the sec- 0nd padlock from the horizontal position shown in FIG.

2 toward a vertical position.

The spacing of the sets of aligned

openings

26 and 27 in the locking bars and the spacing between the lower and

upper corners

28 and 29, respectively, of the ends of the locking bars in the embodiment shown is such that the opposed offset portions 30 on the ends 31 of the locking bars are adjacent to the edges of the transverse recess in the side of the second padlock when it is in position on the upper corners 29 of the locking bars. Thus, ofiset portions 30 accomplish the additional fucntion of limiting swinging movement of the second padlock and providing support to the edges of the transverse recess therein in the same manner as laterally offset portions 32 function with respect to the first padlock.

The outer ends 31 of the locking bars are preferably cut away below the offset portions 30 to provide an overhang 36 which serves to impede attack on the closed end of the transverse recess of a padlock on the lower corners of the locking bars. This feature is not part of the present invention and is not necessary to the accomplishment of beneficial results attained through the use of the invention.

While I have described a preferred embodiment of my invention which provides for the use of two padlocks, it will be apparent that the benefits of the invention are equally applicable to locking bars intended for use with only a single padlock which would normally be mounted on the lower corners on the locking bars. In the single padlock embodiment, the upper set of aligned openings 27 in the locking bars and the offset portions 34 on the upper edges 35 thereof would simply be omitted and the configuration of the top of the locking bars including the upper corner would be a matter of choice.

It will be apparent to those skilled in the art that the highly desirable features afforded by the present invention may be provided at minimal manufacturing cost since the several offset portions may be formed with the same dies and in the same operation used to form the remainder of the locking bar thereby requiring no additional manufacturing steps and no additional material.

lt is understood that various changes in the details, materials, and arrangement of parts, which have been herein described and illustrated in order to explain the nature of the invention, may be made by those skilled in the art within the principle and scope of the invention as expressed in the appended claims.

I claim:

1. In a pair of locking bars in combination with a high security padlock of the type having a body provided with a first recess therein to lockably receive a shackle and a transverse recess generally perpendicular to and intersecting said first recess, said transverse recess being adapted to receive a portion of the outer ends of said locking bars therein, said locking bars each comprising a generally flat plate adpated to be mounted on a door or other item to be secured and each having a portion of the outer end thereof adapted to be received in said transverse recess of said padlock body, said portions of each of said locking bars having aligned openings therethrough to receive said shackle, the improvement comprising abutment means extending outwardly of the side of at least one of said locking bars, said abutment means comprising a portion of said generally flat plate which is ofl'set outwardly of the generally flat surface of said plate and being located near the outer end of said locking bar and adjacent to the portion thereof which is adapted to be received in said transverse recess of said padlock Mdy, the combined thickness of said abutment means and said locking bars being greater than the width of said transverse recess in said padlock body whereby said abutment means are adapted to engage the edges of said transverse recess in said padlock body to prevent said padlock from being improperly mounted on said locking bars and to limit swinging movement of the properly mounted padlock.

2. The improvement as in claim 11 wherein each said locking bars is provided with said abutment means, said abutment means on each locking bar being aligned with and opposed to said abutment means on the other locking bar.

3. The improvement as in claim ll wherein each of said locking bars is provided with additional abutment means extending outwardly of one side thereof near the lower edges thereof and spaced from the outer ends thereof, the combined thickness of said additional abutment means and said locking bars being greater than the width of said transverse recess in said padlock body whereby said additional abutment means are adapted to engage the edges of said transverse recess 7 in said padlock body when said padlock is in position a 4., The improvement as in claim 3 wherein said additional abutment means comprise opposed offset portions of the lower edges of said locking bars.

5. The improvement as in claim 2 wherein said locking bars are generally rectangular in shape providing substantially right angular corners at the top and bottom of the outer ends thereof and having a first set of aligned openings therein spaced from the bottom corners thereof adapted to receive the shackle of a first padlock when said bottom corner portions of said locking bars are received in the transverse recess in the body of a first padlock and having a second set of aligned openings therein spaced from the top corners thereof adapted to receive the shackle of a second padlock when said top corner portions of said locking bars are received in the transverse recess in the body of said second padlock, additional abutment means extending outwardly of the side of at least one of said locking bars, said additional abutment means being located near the top edge of said locking bar and adjacent to the portion thereof which is adapted to be received in said transverse recess of said second padlock body, the combined thickness of said additional abutment means and said locking bars being greater than the width of said transverse recess of said second padlock body whereby said additional abutment means prevent said second padlock from being improperly mounted on said locking bars, said second set of aligned openings being spaced a predetermined distance from said first set of aligned openings whereby said opposed offset portions near the outer ends of said locking bars are adapted to engage the edges of said transverse recess of said second padlock body when said padlock is in position on the upper corners of said locking bars to limit swingng movement of said second padlock with respect to said locking bars and to provide support for said locking bars is provided with said additional abutsaid edges of said transverse recess during an attempt ment means, said means comprising opposed offset to defeat said second padlock by force. portions of said locking bars.

6. The improvement as in claim wherein each of

Claims

1. In a pair of locking bars in combination with a high security padlock of the type having a body provided with a first recess therein to lockably receive a shackle and a transverse recess generally perpendicular to and intersecting said first recess, said transverse recess being adapted to receive a portion of the outer ends of said locking bars therein, said locking bars each comprising a generally flat plate adpated to be mounted on a door or other item to be secured and each having a portion of the outer end thereof adapted to be received in said transverse recess of said padlock body, said portions of each of said locking bars having aligned openings therethrough to receive said shackle, the improvement comprising abutment means extending outwardly of the side of at least one of said locking bars, said abutment means comprising a portion of said generally flat plate which is offset outwardly of the generally flat surface of said plate and being located near the outer end of said locking bar and adjacent to the portion thereof which is adapted to be received in said transverse recess of said padlock body, the combined thickness of said abutment means and said locking bars being greater than the width of said transverse recess in said padlock body whereby said abutment means are adapted to engage the edges of said transverse recess in said padlock body to prevent said padlock from being improperly mounted on said locking bars and to limit swinging movement of the properly mounted padlock.

2. The improvement as in claim 1 wherein each said locking bars is provided with said abutment means, said abutment means on each locking bar being aligned with and opposed to said abutment means on the other locking bar.

3. The improvement as in claim 1 wherein each of said locking bars is provided with additional abutment means extending outwardly of one side thereof near the lower edges thereof and spaced from the outer ends thereof, the combined thickness of said additional abutment means and said locking bars being greater than the width of said transverse recess in said padlock body whereby said additional abutment means are adapted to engage the edges of said transverse recess in said padlock body when said padlock is in position on said locking bars to limit swinging movement of said padlock with respect to said locking bars and to provide support for said edges during an attempt to defeat said padlock by force.

4. The improvement as in claim 3 wherein said additional abutment means comprise opposed offset portions of the lower edges of said locking bars.

5. The improvement as in claim 2 wherein said locking bars are generally rectangular in shape providing substantiaLly right angular corners at the top and bottom of the outer ends thereof and having a first set of aligned openings therein spaced from the bottom corners thereof adapted to receive the shackle of a first padlock when said bottom corner portions of said locking bars are received in the transverse recess in the body of a first padlock and having a second set of aligned openings therein spaced from the top corners thereof adapted to receive the shackle of a second padlock when said top corner portions of said locking bars are received in the transverse recess in the body of said second padlock, additional abutment means extending outwardly of the side of at least one of said locking bars, said additional abutment means being located near the top edge of said locking bar and adjacent to the portion thereof which is adapted to be received in said transverse recess of said second padlock body, the combined thickness of said additional abutment means and said locking bars being greater than the width of said transverse recess of said second padlock body whereby said additional abutment means prevent said second padlock from being improperly mounted on said locking bars, said second set of aligned openings being spaced a predetermined distance from said first set of aligned openings whereby said opposed offset portions near the outer ends of said locking bars are adapted to engage the edges of said transverse recess of said second padlock body when said padlock is in position on the upper corners of said locking bars to limit swinging movement of said second padlock with respect to said locking bars and to provide support for said edges of said transverse recess during an attempt to defeat said second padlock by force.

6. The improvement as in claim 5 wherein each of said locking bars is provided with said additional abutment means, said means comprising opposed offset portions of said locking bars.