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Publication numberUS3550411 A
Publication typeGrant
Publication dateDec 29, 1970
Filing dateJun 13, 1968
Priority dateJun 13, 1968
Publication numberUS 3550411 A, US 3550411A, US-A-3550411, US3550411 A, US3550411A
InventorsNeary Ralph E, Schlage Ernest L
Original AssigneeSchlage Lock Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Lock protecting mechanism
US 3550411 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

DCC. 29, 1970 R, E, NEARY El' AL LOCK PROTECTING MECHAN I SM 4 Sheets-Sheet l Filed June 13, 1968 DeC. 29, 1970 R E, NEARY El' AL 31,550,411

LOCK PROTECTING MECHANISM Filed June 15, 1968 4 weeks-sheet 2 aw WJ# 4r raP/vi/f Dec. 29, 1970 R E, NEARY ET AL 3,550,411

LOCK PROTECTING MECHANISM Filed June l5, 1968 4 Sheets-Sheet 5 Dec. 29, 1970 R, E, NEARY ET AL 3,550,41

LOCK PROTECT ING MECHAN SM Uited States Patent O U.S. Cl. 70-370 2 Claims ABSTRACT OF THE DISCLOSURE A protective lock mechanism includes shells applicable to a door and having portions to overlie and cover lock units installed thereon except for access holes for keys or manual operators, the shells having interior lugs received in extra bores through the door and engaging capped fastening screws disposed in opposite directions.

This application is a continuation-in-part of an application entitled Lock Mechanism led in the name of Ralph E. Neary on Oct. 31, 1966 with Ser. No. 590,564, and now abandoned and assigned ot the assignee hereof.

Our invention generally relates to locking devices and particularly to those portions of a lock mechanism exposed on the side faces of a door panel and carrying the key-receiving portion or other operating or exposed portions of a lock unit.

Some lock units mounted on door panels, for example, project from or are exposed on one or both sides of the panel. This is often the case with high security lock units having pin tumbler lock elements operated by a key and disposed on the outside and the inside of a door panel. Sometimes a thumb turn structure or simply a fastening plate is substituted for a key-actuated device on the interior side of the door if high security is not needed at that location. In certain installations, the pin tumbler unit when mounted either with or without intervening spacers projects quite far from the surface of the door panel. It has been found that vandals equipped with pliers or pipe wrenches or comparable tools can engage the projecting, drum-like or circular cylindrical portion of the lock unit surrounding the pin tumbler mechanism. By imposing a severe torque on the projecting portion, the intruder can so disable the lock set that access to the interior can bei gained.

It is therefore an object of the invention to provide a lock protecting mechanism in which the parts exposed on the side of the door panel are not readily engaged by any of the usual tools and are very difficult to turn or dislodge.

Another object of the invention is to provide a lock protecting mechanism which can be added to lock units presently available so that additional security can be provided.

Another object of the invention is to provide a lock mechanism of this sort which will readily indicate tampering.

Another object of the invention is to provide a lock protecting mechanism which is neat in appearance and which `will blend well with lock mechanisms now generally available.

Another object of the invention is in general to provide an improved lock mechanism having more than the customary security.

A further object of the invention is to provide an improved mounting for a lock unit having a protecting mechanism.

3,550,411 Patented Dec. 29, 1970 ICC An additional object of the invention is to provide an improved support for parts of a lock unit having a protecting mechanism.

Other objects together with the foregoing are attained in the various versions of lock protecting mechanism pursuant to the invention described in the accompanying description and illustrated in the accompanying drawings, in which:

FIG. 1 is an elevation of the outside of a door and frame, portions being broken away, showing the lock protecting mechanism mounted thereon;

FIG. 2 is a cross-section to an enlarged scale, the cross-section being taken on the lines 2 2 of FIG. l;

FIG. 3 is a cross-section taken on a plane indicated by the line 3 3 of FIG. 2;

FIG. 4 is a cross-section taken on a plane indicated by the line 4-4 of FIG. 2;

FIG. 5 is a cross-section like FIG. 2 but showing a modified form of lock protecting mechanism;

FIG. 6 is an elevation of a further modified form of lock protecting mechanism;

FIG. 7 is a cross-section taken on planes indicated by the lines 7-7 of FIG. 6;

FIG. 8 is a fragmentary view in vertical elevation of the obverse face of a door panel and its associated frame and on which another modified form of protecting mechanism is mounted;

FIG. 9 is a view similar to FIG. 8 but showing the reverse face of the structure illustrated in FIG. 8;

FIG. l0 is a cross-section to an enlarged scale, the plane of section being indicated by the line 10*10 of FIG. 8;

FIG. 11 is a cross-section to an enlarged scale, the plane of section being indicated by the line 11-11 of FIG. 9;

FIG. 12 is an end elevation of the structure of FIG. 9 in partially disassembled posiiton; and

FIG. 13 is a view comparable to FIG. 12 but showing a modified form of lock protecting mechanism on the obverse side of the door panel.

In one embodiment, as illustrated in FIGS. 1-4 inelusive, a lock mechanism is mounted on a door panel 4 adapted to lie against a stop 6 forming part of a door frame 7, the panel having appropirate hinge mounts 8 on the frame to permit the panel 4 to swing about a hinge axis parallel to the stop 6. The door panel 4 has a pair of planar, parallel sides 9 and 11, the side 9 being considered as the obverse side or outside and the side 11 being considered as the reverse side or inside. In some instances the installation is substantially identical on the opposite sides so that the nominal distinction between them is arbitrary and merely for convenience.

In the instance illustrated in FIGS. 1-4, the door panel 4 is arranged a lock set including a translating lock bolt 13 designed to project, as shown in FIG. l, and also to retract substantially flush with the edge face 14 of the door panel 4. The bolt 13 when projected lies within a ystrike box 16 forming part of or secured in place by a strike plate 17 secured to the door frame. The bolt 13 is translated to and fro by appropriate mechanism 18, not disclosed in detail.

The mechanism 18 is actuated by operation of a plug 21 rotatable about its own axis within a pin tumbler housing 22 mounted in an actuator unit 23. The unit 23 encompassing the housing 22 is of a circular cylindrical envelope configuration having a slightly projecting peripheral rim 24. The unit 23 terminates in a planar, circular face 26 disposed parallel to the face 9 of the door panel. The end face 27 of the rotatable plug 21 projects slightly beyond the planar face 26. A keyway 28 is formed in the plug 21 so that when a key is introduced therein and is rotated with the plug about the plug axis, a lost motion connection retracts or projects the bolt 13.

In many installations a similar arrangement is provided on the reverse side of the door panel, there being a similar actuator mechanism 33 having a peripheral, circular rim 34 beyond which slightly projects the planar face of a rotatable plug 37 having a keyway 38. A keyactuated, pin tumbler mechanism 39 has a lost motion control of the bolt 13.

As an effective way of mounting and interconnecting the parts so far described, both of the pin tumbler actuators 23 and 33 are pierced axially to receive oppositely directed fasteners 41. One of the threaded fasteners 41 extends from the exterior face of one of the actuators 23 or 433 and engages with a threaded bore in the respective one of a pair of oppositely disposed asymmetrical, axial lugs 43, one extending from each of the mechanisms 23 and 33. The other fastener 41 passes through the other actuator and engages the other lug 43.

When installation is made, it is preferred to provide spacers to hold the units 23 and 33 in appropriate locations with respect to the main bore 46 through the door and at proper distances from the outer faces `9 and 11 of the door panel. Thus, in accordance with the present invention, a spacer 51 is disposed between the end of the actuator 23 and the adjacent door face 9. The spacer is a flat, generally circular plate having a cut-out circular portion 52 and a cut-out radial portion 53 receiving the housing 22 and having a pair of circular notches 54 and 55 for clearing the fastener 41 and lug 43. A similar spacer 56 is interposed between the end of the actuator 33 and the face 11 of the donor panel. When the parts are in position and the fasteners 41 are tightened, the two units 23 and `33 are drawn toward each other. The ends of the actuators 23 and 33 abut the spacers 51 and 56 and press them against the door panel to hold the mechanism tightly in position. Appropriate keys can be introduced into the keyways 28 and 38 to rotate the respective pin tumbler plugs and operate the latch bolt 13.

There is a difficulty in that the projecting actuators, whether or not covered with trim rings, afford good engagement for a heavy pair of pliers or a pipe wrench, for example. A twist of either of the units 23 or 33 about the cross axis S7 can bend and break the fastenings 41 and 43 or otherwise destroy much of the lock unit so that the bolt 13 can be withdrawn.

To obviate this situation, we provide in accordance {with the invention and for installation on one side of the panel l9 a protective shell 61. This is centrally in the form of a frustum of a cone 62 symmetrical about the axis 57. The cone frustum at its larger end merges with an elliptical plate 63 having a generally planar surface 64 designed to abut the side 9 of the door panel. The outer surface 66 of the conical portion of the shell is also a planar surface and partly defines a relatively thin wall 67 overlying at least part of the end face of the unit 23. The wall 64 is preferably cut away but only enough to provide a circular opening 68 slightly larger than and in substantial -registry with the end of the circular plug 21 so that free access can be had to the keyway 28 therein. The wall 67 does not interfere with use of the usual actuating key. Part of the interior of the shell 61 is a circular wall 69 to receive and help support the rim 24 and the rest of the shell interior is a partial cone 71 generated about the axis 57.

Preferably, the angle or slope of the exterior, conical frustum surface 62 is such that pliers or a pipe wrench having the usual parallel jaws or even having special conical jaws will not bite into the material of the cone, but rather will slide toward the smaller end of the cone. This angle or slope is so steep and the coefficient of friction between the engaging tool and the material is such as to make the tool slide off rather than engage the cone. To enhance this effect, the exterior of the conical shell is made smooth, even polished. On many cases it is of a hard material such as armor plate. Engagement by any tool normally available is virtually impossible.

Means are provided for holding the shell in place and for preventing it from rotating, so that the eccentric opening 68 therein always -registers with the end of the plug 21. Integral with the elliptical plate 63 are short lugs 72 and long lugs 73. These lugs are close enough together to merge at their bases. One lug 72 has a socket 74 receiving a fastener 76 threadedly engaging a threaded lug 73 on a similar shell 61, Iwhile the other threaded lug 73 receives a similar fastener 76 extending from a socket 74 in the opposite lug 72. The long lugs 73 overlap (FIG. 3) and are duplicated top and bottom to lie with auxiliary bores 77 and 78 extending through the door panel parallel to the main bore 46. Since the long lugs overlap, they and their fasteners are laterally displaced.

If security is not required on the reverse side of the door panel, the arrangement of FIG. 5 is suitable. In this installation, the door panel 91 has an exterior unit 92 held in position by screws 93 passing through an interior thumb turn unit 96 of a standard kind. An interposed closure plate 98 accommodates fasteners 99 in lugs 102 and 103 but is devoid of a conical central portion. The fasteners 99 engage the lugs 72 and 73 on a shell 61 disposed on the other side of the door panel. As before, the spacing of the lugs is such that separate auxiliary bores 106 and 107 are provided for them. In this fashion the exterior mechanism 92 is secure as previously described In some cases there is no manual control on `the interior of the door panel. In those cases an arrangement as shown in FIGS. 6 and 7 is provided. The exterior shell 108 is as before but the inside shell 109 includes a recessed planar plate 110 having lugs and fasteners identical with those of the shell 98 (FIG. 5), for examd ple, and affords complete protection -to the lock unit. The actuator mechanism 33 is secured in placed by screws engaging a spacer 111.

In some instances somewhat less security is adequate and it is desirable to remove less of the door panel. Consequently a comparable but lighter duty arrangement is shown in FIGS. 8-11. Herein the door panel 112 swings, as before, with respect to a frame 113 and carries a locking bolt 114 to engage a strike box 116. Disposed in a main bore 117 through the door is an exterior, keyoperated lock unit 118 connected by fasteners 119 to an interior key-operated lock unit 121. Both lock units are effective upon the bolt 114 in the usual way.

Surrounding each of the lock units 118 and 121 are spacers 122 and 123. These have tubular portions 124 engaging rbeads 126 on the lock units and have planar flanges 127 abutting the adjacent face of the door panel. The lock units are thus properly spaced along the central axis 128.

Adapted to overlie the exterior lock unit 1118 is a protecting shell 131. This has a generally planar face 132 defined by a wall 133 overlying the end of the lock unit except for a circular opening 134 around the rotatable, key-receiving plug 136 of the lock unit. Smoothly merging with the face 132 is a frusto-conical surface 137 extending from the face to the surface of the door panel. This surface is formed on the shell without roughness and at a relatively steep angle so that a tool such as pliers or a `wrench does not ygrip the shell 1but tends to slide off of the surface.

On the interior, the shell 131 has a conical recess 138 opening to the main bore 117 and also has a pair of lugs 139 and 141 passing through cut-outs in the adjacent flange 127 and lying within arcuate channels 142 and 143 cut into the door panel material and constituting offset enlargements of the main bore, which is therefore not circular in entirety. The shell is thus non-rotatable about the axis 128.

The lugs 139 and 141 are internally threaded to re ceive non-removable fasteners 144 rotatably received in an interior shell 146 surrounding the lock unit 121. While the shell 146 is much like the shell 131, it differs in that lugs 147 are relatively short and are in line with channels 148 interrupting the conical surface 149 of the interior shell 146.

The center of gravity of the shell 146 is such that it tends to fall away from the door panel, as shown in FIG. 12, when the fasteners 144 are removed. This affords a visible warning if, as sometimes occurs, an attempt is made surreptitiously to remove the screws pending later tampering.

In some installations only a key is utilized as a knob or handle for moving the door panel. In other instances it is preferred to provide an auxiliary grip so that the panel can more readily be swung. One Way of doing this, as shown in FIG. 13, is to dispose a ring 211 having a toroidal rim 212 on the obverse shell 213 mounted on the door panel 214. All of the surfaces of the ring 211 are surfaces of revolution about the shell axis 216. Since the rim 212 can be engaged by an ordinary tool and so rotated, it is attached to the shell 213 only through a relatively thin web 217 secured by a band 218 of yieldable adhesive. The ring 211 is attached strongly enough for normal pushing and pulling, but any attempt to rotate it strongly enough to budge the shell 213 causes the adhesive band 218 to fail. The lock unit is still protected by the conical shell 213. The interior can be provided with a thumb turn 219 or can be arranged with an interior shell as in FIG. 12.

It is preferred, especially in the FIGS. 1-7 devices, t0 slip protective covers or caps over all of the exposed fastener heads. These are ordinarily small cups frictionally received by the recess walls surrounding the fastener heads. As the last step in an installation, after the fasteners have been tightened, the cups are pressed ush into place at least over the exterior fasteners. The caps are not readily removed and preclude removal of the fasteners by ordinary means. For clarity of disclosure the caps are omitted from the drawings. Wherever desired, non-removable fasteners, as shown in FIG. 9, may be used whether or not caps are used.

What is claimed is:

1. A mechanism for use with a door panel having a main bore extending therethrough and adapted to receive a lock actuator unit and having an auxiliary bore extending therethrough alongside of the parallel to said main bore and adapted to receive lugs therein comprising a continuous integral rst shell on one side of said panel and having a central portion overlying and obstructing said main bore except for an opening smaller than said main bore and disposed eccentrically with respect to said main bore, a rst lug on said shell extending into said auxiliary bore, a second shell on the other side of said panel, a second lug on said second shell extending into said auxiliary bore alongside said rst lug and fasteners extending from the opposite sides of said panel through said first shell and said second shell into said auxiliary bore and into engagement with respective ones of said lugs.

2. A mechanism as in claim 1 in which at least portions of said lugs on each of said shells are at and extend in opposite directions alongside each other in said auxiliary bore, and said fasteners are disposed alongside each other.

References Cited UNITED STATES PATENTS 589,021 8/1897 Oefjen et al. 70-56 756,447 4/1904 Von Wobeser 292-337 1,518,996 12/1924 Haunder 70-370 1,814,961 7/1931 Phillips 292-346 1,929,658 10/1933 Solliday 70-156 2,312,643 3/ 1943 Hoettels 70-370 3,260,081 7/1966 Simon 70-370 3,343,386 9/1967 Hall 70-427 1,013,524 1/1912 Voight 70-374 FOREIGN PATENTS 491,116 8/1938 Great Britain 70-381 649,247 1/ 1951 Great Britain 292-347 STEPHEN J. NOVOSAD, Primary Examiner R. L. WOLFE, Assistant Examiner

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3698217 *Jun 22, 1971Oct 17, 1972Roy FernandDoor lock guard
US3768284 *Jun 29, 1972Oct 30, 1973R KentMaximum security lock assemblies
US3821886 *Mar 9, 1972Jul 2, 1974Ladewig WPick-proof locks
US3851508 *Jan 22, 1973Dec 3, 1974Amerock CorpSingle and double cylinder deadlocks
US3899907 *Jun 18, 1973Aug 19, 1975Prahl HermanCylinder lock assembly
US4784252 *Mar 2, 1987Nov 15, 1988Davis Wallace EDouble door front locking newspaper vending machine
US5029460 *Jul 20, 1989Jul 9, 1991George AnastasiouRe-enforcer plate with different patterns of threaded holes for locks
US5125696 *Oct 12, 1990Jun 30, 1992Emhart Inc.Cylindrical lock assembly
US5351513 *Mar 1, 1993Oct 4, 1994Baldwin Hardware CorporationDouble cylinder deadbolt
US5826924 *Jul 25, 1997Oct 27, 1998Taiwan Fu Hsing Industry Co., LtdLock assembly with emergent forcible unlatching from outside
US5845522 *Mar 10, 1997Dec 8, 1998Shen; Mu-LinFastening arrangement for a cylindrical lock
US5906125 *Oct 22, 1997May 25, 1999Shen; Mu-LinAuxiliary lock
US6223572 *Sep 9, 1999May 1, 2001Asa Alfret MarttinenDoor lock furniture
US6279360 *Aug 17, 1999Aug 28, 2001Shen Mu-LinCylindrical lock with simpler positioning assembly
US6434986 *Apr 18, 2000Aug 20, 2002Ncr CorporationLock protection
US6698260 *Feb 6, 2002Mar 2, 2004Frank SuInteriorly reinforced door lock set
US6979029Dec 10, 2003Dec 27, 2005Shen Mu-LinLock with increased torque-resisting capacity
US7219519Dec 27, 2005May 22, 2007I-Tek Metal Mfg. Co. LtdCylinder housing for auxiliary lock
US7377134 *Dec 1, 2005May 27, 2008Mcgard, LlcRingless meter lock
US20130312468 *May 23, 2013Nov 28, 2013Bridgestone Capital, Llc.Single key, interchangeable cylinder lock
EP0281519A2 *Feb 25, 1988Sep 7, 1988Ernst KellerDevice for installing a cylinder lock
EP0370893A1 *Nov 21, 1989May 30, 1990Etablissements CaversProtection device for cylinder locks
EP1688565A1 *Jan 9, 2006Aug 9, 2006Massimo ValenteLock with improved security against tampering
WO1997030253A1 *Feb 7, 1997Aug 21, 1997Papaiz Industria E Comercio Ltda.A protection applied to a lock cylinder and key for application thereof
U.S. Classification70/370, 70/416, 70/417, 70/452
International ClassificationE05B15/00, E05B15/16
Cooperative ClassificationE05B15/1614
European ClassificationE05B15/16B