US3111833A

US3111833A - Draw lock for a sealed cabinet door

Info

Publication number: US3111833A
Application number: US115968A
Authority: US
Inventors: Martin H Dettmer
Original assignee: Chicago Lock Co
Current assignee: Chicago Lock Co
Priority date: 1961-06-09
Filing date: 1961-06-09
Publication date: 1963-11-26
Anticipated expiration: 1980-11-26

Description

Nov. 26, 1963 M. H. DETTMER DRAw Loox EoR A SEALED CABINET DooR 2 Sheets-Sheet 1 Filed June 9, 1961 Nov. 26, 1963 M. H. DETTMER DRAW LOCK FOR A SEALED CABINET DooR Filed June 9, 196i I 2 Sheets-Sheet 2 United States Patent O 3,111,833 DRAW LCK FOR A SEALED CABINET DQR Martin H. Dettmer, Des Plaines, Ill., assignmto Chicago Lock Company, Chicago, lll., a corporation of Illinois Filed June 9, 1961, Ser. No. 115,968 17 Claims. (Cl. 70--14tl) The improved draw lock comprising the present invention has -been designed `for 'use primarily in connection with a coin-operated, refrigerated, vending machine cabinet of the type fwhich is commonly utilized in public places and serves as a medium for `dispensing such products as milk, bottled soft drinks, measured quantities of soft drinks in paper drinking containers, prepared sandlwiches, and the like. The invention may, however, be found useful in connection with a nonrefrigerated vending machine cabinet for `dispensing chewing gum, candy bars and edible products of asimilar nature, or with a vending machine `which is designed to dispense such articles as toothbrushes, combs, handkerchiefs and a wide variety of sundries too numerous to mention. irrespective, however, of the particular use to which the present draw Ilock may be put, the essential features of the invention are at all times preserved.

Vending machine cabinet doors, particularly the doors which are associated with refrigerated cabinets, are heavily gasketed and, upon closure thereof, it is necessary to compress the `gaskets tightly so that there will be no heat losses iaround the door jambs. The degree of pressure which must be exerted by the marginal region of a given door against its sealing gasket to effect the necessary hermetio seal is appreciable, considering the size of the average refrigerated vending machine door, and for this reason, suiiicien-t torque cannot be applied to the usual closure cam through the medium of the key-operated lock cylinder of the door-locking mechanism to move the cam to its operative or locked position, or in the case of a screw-in type of locking element, to draw the door against the sealing gasket with any appreciable degree of force. It has, therefore, long been the practice to divorce or separate either the draw cam or draw screw from any association with the lock cylinder and to employ for torque-applying purposes a deep set hexa-gonal socket which is designed for cooperation with a suitable wrench, the lock cylinder serving merely as a removable accessprevention device for the socket, as well as serving norm-ally to conceal the socket when the lock cylinder is in position within the lock barrel. Door locking mechanisms of this character are possessed of numerous limitations and principal among these is the fact that the service man or other operator, upon removal of the lock cylinder to gain access to the torque-applying socket, must hold in his hand or otherwise keep track of the removed lock cylinder and key therefor or incur the danger off misplacing them. Additionally, the operator, in order to lock and unlock the door, must produce the necessary wrench and, after using it, avoid the danger of misplacing it. In addition, iitting of the wrench into the socket .and subsequent replacement of the `lock cylinder into the lock barrel are time-consuming operations.

The present invention is designed to overcome the above-noted limitations that are attendant upon the construction and use of conventional vending machine doorlocking mechanisms, and toward this end, it contemplates the provision of `a novel assembly of parts including front and rear housings which are capable of assembly upon a refrigerator or similar door from opposite sides thereof respectively so as to assume a position of alignment. The rear housing carries the usual rotatable draw element which may be either a draw screw or a draw cam, lwhile the front housing carries a rotatable operating handle for the draw element. The operating handle and suisse Patented Nov. 26, 1963 ice draw element are provided with interengaging clutch parts respectively. The operating handle has formed therein a cylindrical bore which receives therein the 4lock barrel and cylinder assembly. The operating handle is extensible and retractable out of and into the front housing. When in its retracted position, a key-operated latch plate maintains the handle thus retracted, while at the same time, the clutch parts remain disengaged. When the lock mechanism is operated to cause the latch plate to release the operating handle and the latter is pulled outwards to its fully extended position, the clutch parts become automatically engaged so that, upon turning of the handle, the draw element may likewise be turned. Means are provided for preventing complete removal of the operating handle from the front housing and thus the service man or other operator requires no separate operating tool-s for door-opening or closing movements, nor is he obliged to hold or temporarily to set aside any lock parts during his servicing procedure, an operating key Ifor the lock mechanism being the only adjunct necessary to dooropening `and closing operations.

The provision of a locking mechanism of the character briey outlined above being among the principal objects of the present invention, it is a further object to provide such a mechanism wherein the front housing, when installed on theV door, lies `substantially within the confines of the door and has no protruding parts, and wherein the operating handle, -when in its retracted position, lies wholly within the contines of the front housing.

Another object of the invention is to provide such a locking 'mechanism wherein the clutch parts thereof are spring-loaded in such a manner that immediately upon release of the key-operated latch plate, the operating handle is automatically projected to its fully extended position While the clutch parts become automatically engaged, thus making it unnecessary for the operator to resort to manual clutch-engaging operations.

Still another object of the invention is to provide such a lock mechanism |wherein replacement of the operating handle in the front housing after a door-closing operation has been eiiected, may be accomplished by orientation of the handle to either of two angular positions, the latch pin by means of which the handle is maintained retracted being provided with selectively operable cooperating latch Iwear plates, one of which becomes effective when the handle is in one position, and the other of which becomes effective when the handle is in the other position.

The provision of a locking mechanism which may be manufactured and installed as original equipment on a vending machine cabinet door or may be applied to an existing door installation with a minimum of modification; one which is readily adaptable to use in connection with doors of varying thicknesses without requiring structural modification other than a selection of different length spacer sleeves; and one which otherwise is well-adapted to perform the services required of it; are further desiderata which have been borne in mind in the production and development of the present invention.

With these and other objects in View, which will become more readily apparent as the nature of the invention is better understood, the invention consists in the novel construction, combination and arrangement of parts shown in the accompanying two sheets of drawings forming a part of this specification.

In these drawings:

FIG. 1 is a front elevational view of a draw lock assembly constructed in accordance with the principles of the present invention and employing a draw screw for door-closing purposes;

FIG. 2 is a sectional view, partly in elevation, taken substantially centrally, axially and vertically through the draw lock and showing the same operatively applied to a refrigerator door;

FIG. 3 is a sectional View similar to FIG. 3 but showing the lock in its condition of clutch engagement;

FIG. 4 is a sectional view taken on the line 4-4 of FIG. 3 and in the direction indicated by the arrows;

FIG. 5 is a sectional View taken on the line 5-5 of FIG. 3 and in the direction indicated by the arrows;

FIG. 6 is a sectional view taken on the line 6-6 of FIG. 2; and

FIG. 7 is a fragmentary sectional view, partly in elevation, taken substantially centrally, axially and vertically through a slightly modified form of the invention wherein a draw cam is employed for door-closing purposes.

Referring now to the drawings in detail, and in particular to FIGS. 1 to 6, inclusive, the improved draw lock of the present invention has, for exemplary purposes, been illustrated herein as being operatively installed upon a refrigerator door 10 of the horizontally swinging type and having inside and outside

door panels

12 and 14, the space existing between the two panels being substantially lled with suitable insulating material 15. The door 10, when in its closed position, is adapted to be drawn against a flexible rubber or other elastomeric sealing strip or door gasket 16 which is mounted on the door jamb 18 and is adapted to become compressed between the panel 12 and jamb 18. In the form of the invention shown in FIGS. 1 to 6, inclusive, the pressure necessary to draw the door 10 against the gasket 16 is effected under the control of a draw screw 2t) and cooperating cage nut 22, the nut being held in a oating manner within an encompassing cage 24 which is mounted on a iixed bracket 26 in the usual manner of draw screw and nut cooperation. In FIG. 7, the door 10 is drawn against the gasket 16 by a draw carn 28 which cooperates with a shoulder on a fixed bracket, likewise in the usual manner of draw cam and shoulder cooperation. The two forms of the invention which are exemplified in FIGS. 1 to 6, inclusive and FIG. 7, respectively, are identical except for the use in one instance of the draw screw and in the other instance of the draw cam 28.

As best seen in FIG. 2, the door-locking mechanism involves in its general organization a front housing 40 and a rear housing 42. The front housing 40 is mounted within a relatively large opening 44 in the outside door panel 14, while the rear housing 42 is mounted within a smaller opening 46 in the inside door panel 12. The two

housings

40 and 42 are adapted to be drawn into position against their respective panels and within their respective openings by a pair of tie rods 4S in a manner that will be described in detail hereafter.

The front housing 40 is generally of shallow or dished configuration, it being of vertically elongated, rectangular design as viewed in front elevation (see FIG. l). It has an appreciable vertical extent and a small transverse width and is preferably in the form of a casting having a vertically disposed bottom wall 50 from which there extends forwardly a marginal wall 52 having a laterally turned rim flange 54. The rim flange 54 seats against the outside door panel 14 While the marginal wall 52 is shaped conformably to the opening 44 and lits snugly therein.

The rear housing 42 likewise is preferably in the form of a casting of dished configuration and includes a circular bottom wall 56 and a cylindrical side wall 58. When mounted within the opening 46, the bottom wall 56 lies in a vertical plane while the cylindrical side wall 58 extends forwardly in the direction of the front housing 40. The rear side of the housing 42 is formed with a pair of oppositely extending attachment ears 60 (see FIG. 6), and the previously-mentioned tie rods 48 are in the form of elongated stove bolts which project through the ears 6G and also holes 64 in the inside door panel 12. The forward ends of the tie rods are screw-threaded as at 66 into a pair of oppositely directed, radial attachment lugs 67 which are formed on a circular boss 68 on the rear side of the bottom wall 50 of the front housing 40. Reinforcing gusset webs 70 are formed on the front housing 40 between the lugs 67 and the bottom wall 50. Spacer sleeves 72 are interposed between the attachment ears 60 and the inside panel 12, the length of such sleeves being determined by the over-all thickness of the door 10. When the two tie rods 48 are drawn tight, the front and

rear castings

40 and 42 are securely drawn against the

panels

14 and 12, respectively, the former directly and the latter through the medium of the spacer sleeves 72, and the lock assembly as a whole is thus held in position on the door 10.

The vertical bottom` wall 50 of the front housing 40 is formed with a central axial bore 80 within which there is rotatably and slida'bly received the cylindrical hub portion V8.2 of a rotatable torque-applying operating handle 84. The front housing 40 thus constitutes a bea-ring member `for the hub portion 82. r[The handle includes a pair of oppositely extending lever `arms 86 which are arranged in alignment on lopposite sides of the hub 82. As shown in the drawings, the handle 84 is slidable horizontally and axially between a retracted position wherein it `is shown in -FIG. 2 and an extended position wherein it is shown in FIG. 3. In its retracted position, the lever `arms 86 which collectively may be regarded as constituting the handle proper are maint-ained substantially wholly within the confines of the shallow recess 87 which is delined lby the bottom wall S0` :and fthe marginal wall 52 of the front housing 40a In the extended position of the handle, the lever arms 86 are disposed an appreciable distance forwardly of the vertical plane of the outside panel 14.

rl`he rear end of the hub portion 82 orf the handle 84 is Iformed with `a -reduced threaded extension 818 which receives thereover one end of @a hardened steel clutch sleeve 90", the sleeve projecting rearwardly of the hub portion 812 of the handle y814 so as to constitute, in effect, an extension of the hub and being formed at its rear end with a clutch socket 92 of hexagonal conliguration. An external radial ange 94 -is formed on the sleeve 90 in the medial region thereof and functions as a limit stop to determine the fully extended or forward position of lthe handle 84.

The clutch socket 92 is designed for cooperation with a clutch head 96 which is formed on the front end of a rotatable draw shaft i100 and is hexagonal in shape. The draw shaft 100' extends horizon-tally through a bore 102 in the vertical bottom Iwall 56 of the rear housing 42, is rotatable therein, and h-as its medial regions centered Within an opening between a radial rear flange i104 and -a snap ring 106 in an :annu-lar groove 108' in the shaft 100. The housing 42 thus constitutes a bearing member for the draw shaft 100. The portion of the shaft 100 which projects rearwardly of the groove 1018 constitutes the previously-mentioned draw screw 20'. Normally, in the retracted position of the handle 84, the forward region of the shaft 100 projects through the clutch `socket 92 and` is telescopically received wit-hin the sleeve 901 so that the clutch head 96 assumes the disengaged position wherein it is shown in FIG. 2 well within the contines of the sleeve. A compression spring 1 10 surrounds the sleeve 94]'` and the shaft 100 and yieldingly urges the sleeve 9@l -and its attached handle 84 toward their extended vor forward position.

When the refrigerator cabinet lis not being serviced, the y,door ltlv is normally maintained -in its closed position and the handle 84 is maintained in its retracted position wherein the lever arms 86 are nested within the confines of the dished front housing 40, as shown in FIG. 2, while the clutch head 96 is maintained disengaged from the clutch socket 92. These parts are thus maintained retracted and disengaged by means of a latch plate 112 (see FIGS. 2 and 5) which is operable under the control of a lock `assembly 1'14 as will be described presently. The latch plate 112 is slidable within a transverse guideway -116 in rthe hub portion .68 of the operating handle 84 yand it .is spring-pressed as at 11S so that the head portion I120 thereof its normally projected radially outwardly beyond lthe confines of the tguideway 116. The rrear end region of the circular boss `68 of the front housing 40 is slotted as at 122 to provide clearance voids for the head portion 120 of the latch plate 112 and a pair of hardened steel wear plates 124 are aixed by means of fastening screws 126 to the bottom faces of the slotted regions of the hub portion 68 and are designed for selective engagement with the latch plate 120, depending upon the particular position of the handle proper when it is received within the front housing 40. In FIG. 2, the latch plate .112 is shown as being in registry with the upper wear plate 124, but it will be understood that in la situation wherein the position of the handle 84 -is reversed or turned throughout an angle of 180, lche latch plate 120 will be in registry with the lower wear plate 124.

T-he lock lassembly by means of which the latch plate 112 may be moved to its retracted position against the action of the spring 118 has been designated 4in its entirety by the reference numeral 130. 'Ihis lock assembly is purely conventional in its design and construction and no claim is m-ade herein to any novelty `associated with the same other than its novel association with the handle 8-4 and the latch plate 112. The assembly 130 includes the usual ygenerally cylindrical, open-ended, outer lock barrel 132, an inner rotatable tumbler-carrying plug or lock cylinder 136i, andan operating key 138 for the cylinder (see PIG. 3). 'Ihc barrel is fixedly mounted in a relatively deep cylindrical socket 140 in the handle 84 and extends well into the hub portion 82 of the latter. The inner end of the socket 140' communicates with the transverse latch plate gu-ideway 116.

As best shown in FIG. 4, the Ibarrel 132 is formed with the usual diametrically disposed tumbler grooves 142 which afford clearance spaces for conventional tumblers 144 in associated relation with the lock cylinder 136. The latter is provided with the usual keyway 146 and the rear end face of the cylinder is provided with an eccentric pin 14Sl (see FIG. 4) which projects into a slot 150 (see FIG. 5) in the latch plate '1112.

From the foregoing description, it will be seen that, upon turning of the lock cylinder 136 in a counterclockwise direction, -as viewed in lFIG. 4 throughout an angle of 90, the eccentric pin .14S will describe a 90 arc, and in so moving, it will ride in the slot .150 and cause the latch plate 11-2 to be moved from its projected position olf registry with one of the wear plates 124 to a retracted position wherein it is wholly withdrawn into the connes of the lock cylinder `136. With the latch plate 112 thus retracted, 4the entire handle yassembly 84 and its contained lock `assembly 130 lmay the slid axially forwardly and bodily as a unit .within the bore 80 in the circular boss `68` of the front housing -40 to move the handle 86 to its extended position, `as shown in FIG. 3, and at the same time, disenga-ge the clutch head 96 from the clutch socket 92.

The forward rim region of the socket St) in the hub portion 82 of the handle 84 is formed with a frustoconical surface 160 having a slant angle substantially equal to the slant angle of the outer end face 162 of the head portion 120 of the latch plate 112 and of small slant height. This frusto-conical surface 160 serves as a cam surface for effecting automatic retraction of the latch plate 112 into the hub portion 82 as the handle 84 and its attached sleeve 9) are slid rearwardly toward the rear housing 42 during restoration of the handle 84 to its nested position within the front housing 411.

In the operation of the preferred form of vending machine locking mechanism, shown in FIGS. l to 6, inclusive, the service operator, carrying the proper key 133, will insert it in the keyway 146 of the lock cylinder 136 and, by turning it, release the latch mechanism which holds the lock assembly 130 in position within the socket 140. Such release is effected by movement of the latch plate out of register with the adjacent wear plate 124 under the iniiuence of the eccentric pin 148 in the slot 150 (see FIG. 5) as previously described. As soon as the outer end of the latch plate 112 moves radially inwardly beyond the inner edge of the wear plate 124, the

handle 84 and its attached clutch sleeve 90 are released, and under the influence of the spring 11), the handle 84 is projected forwardly to its fully extended position as limited by engagement of the flange 94 with the end of the circular boss 68. At the same time, the clutch socket 92 moves into telescopic relationship with respect to the clutch head 96 on the inner end of the clutch shaft 10). The operating handle 84 is thus accessible for manipulation and, thereafter, by manually turning the handle 84 in a counter-clockwise direction as viewed in FIG. l, the torque thus applied to the handle will be transmitted through the sleeve 90, the

clutch parts

92, 96, and the shaft 100 to the draw screw 20 which will, upon continued turning of the handle, become unthreaded from the cage nut 22 on the fixed bracket 26 on the refrigerator cabinet. The refrigerator door 10 may then be swung to its open position for whatever servicing operations may be required. The lock assembly 130 is preferably, but not necessarily, designed according to well-known engineering expediencies so that the key 133 may not be removed from the keyway 146 of the lock cylinder 136 after it has been turned from its normal position in the cylinder 13@ when the latter is in its locked condition. Therefore, by leaving the key thus turned while the refrigerator door 10 is open, there will be no danger of misplacing the key.

After servicing operations have been completed, the door lil may be closed and locked by a reversal of the unlocking operations described above. Initially, the door 10 will be moved toward its closed position until such time as the end of the draw screw 2t) moves into register and engagement with the cage nut 22, after which the handle will be turned in a clockwise direction to transmit torque to the draw screw through the medium of the engaged

clutch parts

92 and 96, as shown in FIG. 3. During such turning movement of the handle 84, the spring will serve to maintain the clutch parts in operative engagement without requiring any attention on the part of the operator. After the door has been drawn against the gasket 15 with the necessary degree of pressure to effect the desired seal, and as ascertained by the sense of feel of the experienced operator, the handle S4 may be given the slight additional turn required to bring either lever arm 86 into registry with one side of the shallow recess 87 of the front housing 4t), after which the handle may be forced rearwardly and into the recess to disengage the

clutch parts

92 and 96 and restore the various operating instrumentalities of the locking mechanism to the position wherein it is illustrated in FIG. 2. During such rearward movement of the handle 84, the inclined outer end surface 162 of the latch plate 112 will engage the frusto-conical surface 160 at the rim of the socket 80 in the circular boss 68 of the front housing 40, and by a camming action, the latch plate 112 will be retracted into the confines of the hub portion 82 whereupon it will slide rearwardly on the wall of the bore S0 until such time as it clears the rear rim of the bore, after which it will snap into its extended position immediately behind one or the other of the two wear plates 124, thus eHectively locking the handle in its retracted position and maintaining the clutch parts $2 and 96 out of operative engagement with each other.

In order to render the lock assembly interchangeable with other similar assemblies, the hub portion 82 of the handle 84 is provided with a radially disposed set screw 170, the inner end of which is designed for registry with a small depression 172 in the side of the lock barrel 132. The depression 172 not only cooperates with the inner end of the set screw 170 in maintaining the barrel, and, consequently, the lock assembly, in position in the socket 140 of the hub portion 82, but also it serves as a locating socket for assuring proper installation of the barrel in the socket and proper orientation of the lock cylinder 136 with respect to the transverse slot 150 in the latch plate 112.

It is to be noted that when the handle 84 is in its retracted position the set screw 170 is inaccessible and cannot be removed. When the handle S4 is in its extended position as shown in FIG. 3, the set screw 711 is uncovered for removal or release purposes.

Whereas in the form of the invention illustrated in FIGS. 1 to 6, inclusive, the refrigerator door 10 is drawn into sealing engagement with the sealing gasket 16 under the influence of a cooperating draw screw 20 and cage nut 22, in the form illustrated in FIG. 7, the seal is made effective by means of the previously-mentioned draw cam 28. This draw cam cooperates with a ange 180 on a suitable bracket 182 which is fixedly mounted on a stationary part of the refrigerator housing or framework. The draw shaft 134, the rear housing 186, and the numerous other instrumentalities in associated relation with the locking mechanism of FIG. 7 remain substantially the same as in the previously-described form of the invention and require no description herein. The draw cam 28 is provided with the usual cam surface 185 and is affixed to the draw shaft 184 by means of a nut 187 on the rear end of the shaft 184. A washer 188 is interposed between the nut 187 and a rearwardly facing annular shoulder 190 formed on the draw shaft 184.

It is to be noted at this point that, in either form of the invention disclosed herein, i.e., the form shown in FIGS. 1 to 6, inclusive, wherein the draw shaft 100 carries the draw screw 20 for drawing the cabinet door against the sealing gasket 16, or the form shown in FIG. 7 wherein the draw shaft 184 carries the draw cam 28 for accomplishing the same purpose, the common operating medium for effecting the door-drawing operation operates upon a cam principle. In the case of the 4draw cam 28, the cam surface 185 thereof effects the actual drawing operation when the cam is swung about the axis of the draw shaft 184. In the case of the draw screw 20, the direction of the screw helix affords a continuous elongated cam surface which cooperates with the interengaging internal screw thereof, the cage nut 22 to draw the door 1@ to its closed position in sealing engagement with the elastomeric sealing gasket 16. By these tokens, in the accompanying claims, reference to cam means for effecting the drawing operation may be construed as being applicable to either form of the invention illustrated and described herein.

While there have been shown, described, and pointed out the fundamental novel features of the invention as applied to a preferred embodiment of the invention and to an alternative embodiment, it will be understood that various omissions, substitutions, and changes in the form and details of the mechanism illustrated, as well as in its operation, may be made by those skilled in the art without departing from the spirit or scope of the invention. It is the intention, therefore, to be limited only as indicated bythe scope of the following claims.

Having thus described the invention what I claim as new and desire to secure by Letters Patent is:

1. In a draw lock for a sealed cabinet door, in combination, a front bearing member adapted to be installed in a door lock opening through the outside face of the door, a rear bearing member adapted to be installed in said opening through the inside face of the door, an operating handle positioned forwardly of the front bearing member and having a hub portion projecting through the front bearing member and rotatable and slidable axially therein, a draw shaft projecting through the rear bearing member in axial alignment with said hub portion, means preventing endwise axial shifting of the draw shaft with respect to the rear bearing member, a draw cam on said draw shaft rearwardly of the rear bearing member and designed for camming engagement with a xed shoulder on a cabinet to which the door is applied, said operating handle and hub portion being movable bodily as a unit between a retracted position wherein the handle assumes a position in close proximity to the front bearing member and an extended position wherein the handle is projected forwardly of the front bearing member, a rst clutch element on said draw shaft forwardly of the rear bearing member, and a second clutch element on said hub portion rearwardly of the front bearing member and movable bodily with the hub portion and operating handle, said second clutch element being disposed rearwardly of the first clutch element when the handle is in its retracted position and being movable forwardly into cooperating engagement with the first clutch element as the handle is moved forwardly to its extended position.

2. In a draw lock for a sealed cabinet door, the cornbination set forth in claim l and wherein the front bearing member is provided with a recess in the forward side thereof within which the operating handle is nested when the latter is in its retracted position and from which it is projected when the handle moves toward its extended position.

3. In a draw lock for a sealed cabinet door, the combination set forth in claim 1 and wherein said operating handle includes a pair of oppositely directed, elongated, lever arms which project radially outwardly from the hub portion at right angles thereto, said front bearing member being provided with a forwardly extending, marginal flange having a contour conformable to the contour of said lever arms and within the confines of which flange the lever arms are nested when the operating handle is in its retracted position.

4. In a draw lock for a sealed cabinet door, the combination set forth in claim l and wherein the hub portion of the handle is provided with a hollow tubular extension on the rear end thereof and into which extension the forward end of the draw shaftprojects, said rst clutch element being in the form of a noncircular head on the forward end of the draw shaft and said second clutch element being in the form of a noncircular socket conformable in shape to the contour of the noncircular head and disposed at the rear rim of said hollow tubular extension.

5. In a draw lock for a sealed cabinet door, the combination set forth in claim 1 and wherein said hub portion of the handle is provided with a reduced threaded rear end region, a clutch sleeve having one end threadedly received on said threaded region of the hub portion, the forward end region of said draw shaft projecting into said clutch sleeve through the rear end thereof, the forward end of the draw shaft being formed with a polygonal clutch head constituting the rst clutch element, the rear end of the clutch sleeve being formed with a polygonal clutch socket constituting the second clutch element.

6. In a draw lock for a sealed cabinet door, in combination, a front bearing member adapted to be installed in a door lock opening through the outside face of the door, a rear bearing member adapted to be installed in said opening through the inside face of the door, an operating 4handle positioned forwardly of the front bearing member and having a hub portion projecting through the front bearing member and rotatable and slidable axially therein, a draw shaft projecting through the rear bearing member in axial alignment with said hub portion, means preventing endwise axial shifting of the draw shaft, a draw cam on said -draw shaft rearwardly of the rear bearing member and `designed for camming engagement with a fixed .shoulder on a cabinet to which the door is applied, said opening handle and hub portion being movable bodily as a uni-t between a retracted position wherein the handle assumes a position in close proximity to the front bearing mem'ber and an extended position wherein the handle is projected forwardly of the front bearing member, a first clutch element on said draw shaft forwardly of the rear bearing member, a second clutch element on said hub portion rearwardly of the front bearing member, said second clutch element being disposed rearwardly of the first clutch element when the handle is in its retracted position and being movable forwardly into `cooperating engagement with the first clutch element as the handle is moved forwardly to its extended position, cooperating latch means on said front bearing mem-ber and hub portion for releasably maintaining said operating handle in its retracted position, and key-operated means for disabling said latch means.

7. In a draw lock for a sealed cabinet door, in combination, a front bearing member adapted to be installed in a door lock opening through the outside face of the door, a rear bearing member adapted to be installed in said opening through the inside face of the door, an operating handle positioned forwardly of the front bearing member and having a hub portion projecting through the front bearing member and rotatable and slidable axially therein, a draw shaft projecting through the rear bearing member in axial alignment with said hub portion, means preventing endwise axial shifting of the draw shaft, a draw cam on said draw shaft rearwardly of the rear bearing member and ldesigned for camming engagement with a fixed shoulder on a cabinet to which the door is applied, said operating handle and hub portion being movable bodily as a unit `between a retracted position 'wherein the handle assumes a position in close proximity to the front bearing member and an extended position wherein the handle is projected forwardly of the front bearing member, a first clutch element on said draw shaft forwardly of the rear Ibearing member, a second clutch element on said hub portion rearwardly of the front bearing member, said second clutch element being disposed rearwardly of the first clutch element when the handle is in its retracted position and being movable forwardly into cooperating engagement with the first clutch element as the handle is moved forwardly to its extended position, a l-atch plate slidably disposed in said hub portion rearwardly of the front bearing mem- 'ber when the handle is in its retracted position and movable between an advanced position wherein it projects outwardly beyond the confines of the hub portion for latching engagement with a shoulder on the front bearing member to maintain the handle in i-ts retracted position, and a retracted position wherein it is withdrawn into the confines of the hub portion to release the handle, said handle and hub portion being formed with a forwardly opening, axially extending socket therein, a lock assembly including a lock barrel disposed in said socket, and a lock cylinder rotatable in said barrel, and interengaging means on said cylinder and latch plate for retracting the latch plate upon turning movement of the cylinder in one direction.

8. In a draw lock for a sealed cabinet door, the cornbina-tion set forth in claim 7 and including, additionally, spring means yieldingly urging said latch plate toward its advanced position, said interengaging means operating, when the cylinder is turned in said one direction, to retract the latch plate against the action of said spring means.

9. In a draw lock for a sealed cabinet door, the combination set forth in claim 7 and wherein said hub portion is formed with a threaded radial Ibore therein and which, when the handle is in its retracted position, is disposed between the `front and rear confines of the front bearing member, and a set screw threadedly received within said radial bore and engageable with said lock barrel for releasably maintaining the lock assembly in position within the socket.

10. In a draw lock for a sealed cabinet door, the

10 combination set forth in claim 7 and wherein the front bearing member is provided with a recess in the forward side thereof within which the operating handle is nested when the latter is in its retracted position and from which it is projected when the handle moves toward its extended position.

l1. In a draw lock Ifor a sealed cabinet door, the combination set forth in claim 7 and wherein said operating handle includes a pair of oppositely directed, elongated, lever arms which project radially outwardly from the hub portion at right angles thereto, said front bearing member being provided with a forwardly extending, marginal flange having a contour conformable to the contour of said lever arms and within the yconfines of which flange the lever arms are nested when the operating handle is i-n its retracted position.

l12. In a dra-w lock for a sealed cabinet door, the combination set forth in claim 7 and wherein the huh portion of the handle is provided with a hollow tubular extension on the rear end thereof and into which extension the forward end of the draw shaft projects, said rst clutch element being in the form of a noncircular head on the forward end of the draw shaft and said second clutch element being in the form of a noncircular socket conformable in shape to the contour of the noncircular head and disposed at the rear rim of said hollow tubular` extension.

13. In a draw lock for a sealed cabinet door, the combination set forth in 'claim 7 and wherein said hub portion of the handle is provided with a reduced threaded rear end region, a clutch sleeve having one end threadedly received on said threaded region of the hub portion, the forward end region of said draw shaft projecting into said clutch sleeve through the rear end thereof, the forward `end of the :draw shaft being formed with a polygonal clutch head constituting the first |clutch element, the rear end of the clutch sleeve being formed with a polygon-al clutch socket constituting .the second clutch clement.

14. In a draw lock for a sealed cabinet door, in combination, a front housing .adapted to be installed in a door llock opening through the oultside face of the door, a rear housing adapted to be installed in said opening through the inside .face of the door, an operating handle positioned forwardly on Ithe yfront bearing member and having a hub portion projecting through the front housing and rotatable and slidable axially therein, a draw shaft projecting through the rear housing in axial -alignment with said hub portion, means preventing axial shifting of the draw shaft, a draw cam ion said draw shaft rearwardly of the rear housing [and designed yfor camming engagement with a fixed shoulder on ia cabinet to which the door is applied, said operating handle and hub portion being movable bodily las Ia unit between a retracted position wherein the handle assumes a position in cl-ose proximity to the front housing and an extended position wherein the handle is projected forwardly of the fron-t housing, each of said housings being of cup-shape design and having the open rim portion thereof presented forwardly, said hub portion projecting into the rear housing through the open rim thereof when the handle is in its retracted position, the rear end of said hub portion being provided with a relatively deep cylindrical socket therein into which the forward `end of the draw shaft projects, a polygonal clutch head on the forward end of the draw shaft, the rim portion of said pocket being formed with a cooperating polygonal yclutch surface conformable in conguration to the configuration o-f said clutch head, said clutch surface being movable forwardly into cooperating engagement with the clutch head as the hand-le is moved forwardly to its extended position, a spring disposed within said rear housing, surrounding said hub portion and bearing a-t its opposite ends against the rear housing and hub portion respectively for normally urging said handle toward its extended position, and key-operated releasable latch 11. means for normally maintaining said handle in its retr-acted position.

15. In a draw lock for a sealed cabinet door, in cornbination, la housing structure adapted to be installed in an opening in the door `and embodying -front and rear internal bearings, yan openating handle positioned forwardly of the housing structure yand having a hub portion projecting rearwardly through the front internal bearing and rotatable and axially `slidafble therein, a draw shaft projecting forwardly through the rear bearing and in axial alignment with sai-d hu-b pontion, means for preventing axial shifting `of the draw shaft with respect to the rear bearing, a draw cam on said draw shaft rearwardlyrof the rear bearing member and designed for camming engagement with a substantially xed shoulder on a cabinet -to which the door is applied, said operating handle Iand hub portion being movable bodily as a unit between a retraoted position wherein the handle assumes a position in close proximity to the Ifront ybearing and an extended position wherein the handle is projected forwardly of the `front bearing, a first clutch element on said draw shaft forwardly of the rrear bearing, and a second clutch element on said hub portion rearwardly or the front bearing and movable :bodily with the hnb portion yand operating handle, said second clutch element being disposed rearwardly of fthe first clutch element when the handle is in its retracted position and being movable forwardly into cooperating engagement with the rst clutch element as the handle is moved forwardly to its extended position.

16. In a draw lock 'for a sealed cabinet door, the combination set forth in claim 15 and including, additionally, spring means normally urging said operating handle t0- ward its extended position.

17. ln `a draw lock #for ,a sealed cabinet door, the com` bination set fonth in claim 15 and including, additionally, `a rim ange at the .front end `of said housing structure adapted to dit against the outer side of the cabinet door and deiining a shallow recess having a contour conformable with the contour of said operating handle and Within the confines `of which the handle is nested when the latter is in its retracted position, spring means normally urging said ioperatingrhandle toward its extended position, and a key-operated lock assembly `disposed within said operating Ihandle and having means associated therewith for holdingV the handle in lits retracted position against the action of said spring means.

l References Cited in the file of this patent UNITED STATES PATENTS 1,668,553 Douglas May 8, 1928 1,776,881 Birdsall Sept. 30, 1930 1,932,048 Robertson Oct. 24, 1933 2,260,785 Miguel Oct. 28, 1941 2,334,012 Koch et al. Nov. 9, 1943

Claims

15. IN A DRAW LOCK FOR A SEALED CABINET DOOR, IN COMBINATION, A HOUSING STRUCTURE ADAPTED TO BE INSTALLED IN AN OPENING IN THE DOOR AND EMBODYING FRONT AND REAR INTERNAL BEARINGS, AN OPERATING HANDLE POSITIONED FORWARDLY OF THE HOUSING STRUCTURE AND HAVING A HUB PORTION PROJECTING REARWARDLY THROUGH THE FRONT INTERNAL BEARING AND ROTATABLE AND AXIALLY SLIDABLE THEREIN, A DRAW SHAFT PROJECTING FORWARDLY THROUGH THE REAR BEARING AND IN AXIAL ALIGNMENT WITH SAID HUB PORTION, MEANS FOR PREVENTING AXIAL SHIFTING OF THE DRAW SHAFT WITH RESPECT TO THE REAR BEARING, A DRAW CAM ON SAID DRAW SHAFT REARWARDLY OF THE REAR BEARING MEMBER AND DESIGNED FOR CAMMING ENGAGEMENT WITH A SUBSTANTIALLY FIXED SHOULDER ON A CABINET TO WHICH THE DOOR IS APPLIED, SAID OPERATING HANDLE AND HUB PORTION BEING MOVABLE BODILY AS A UNIT BETWEEN A RETRACTED POSITION WHEREIN THE HANDLE ASSUMES A POSITION IN CLOSE PROXIMITY TO THE FRONT BEARING AND AN EXTENDED POSITION WHEREIN THE HANDLE IS PROJECTED FORWARDLY OF THE FRONT BEARING, A FIRST CLUTCH ELEMENT ON SAID DRAW SHAFT FORWARDLY OF THE REAR BEARING, AND A SECOND CLUTCH ELEMENT