US2981560A

US2981560A - Latch mechanism

Info

Publication number: US2981560A
Application number: US760368A
Authority: US
Inventors: Wehner Alfred Peter
Original assignee: Individual
Current assignee: Individual
Priority date: 1958-09-11
Filing date: 1958-09-11
Publication date: 1961-04-25
Anticipated expiration: 1978-04-25

Description

April 25, 1961 A. P. wEHNER LATCH MECHANISM Filed sept. 11, 1958 movement between the positions.

.i accompanying drawings inwhich: Y l i top View of oneemblodiment of the present invention; l .j l M .1 1 j Fig.i 2 rsan enlarged c ross-sectien of a latch embodying A zthe present invention, l taken along da line `substantially l corresponding with line` 2j-2.of' Fig. `Lgf; 'A

The present` invention relates to latches for doors, drawers and the like and more particularly to a new mproved latch mechanism of simple, rugged construction and ease of operation and has for an object the provision of a child proof latch readily operated by adults.

Countless accidents occur when children obtain access to drugs, poisons and the like stored in medicine cabinets and closets.

The attempts in the past to keep drugs and dangerous instrumentalities, such as guns, from children have ernployed key operatedV locks and so called secret or hidden fasteners. While such arrangements are for the most part successful they are subject to failure unless the key 2 Fig. 4 is a cross-section of another modification of the present invention; and

Fig. 5 is aperspective view ofa casing employed in the modification of Fig."4.

Referring now to Fig. V1 there is illustrated a latchV mechanism embodying the present invention and shown in a drawer locking relation `with a latching means llldisposedr adjacent drawer 12. The latch 10 is shown secured toja fixed drawer ordoor frame 13 of a cabinet by means of a base portion 14. In accordance with the present invention the latch mechanism may be mounted readily and with the use of the simplest tools to existing furniture withoutthe need for boring holes or otherwise requiring `the services of `a cabinet maker. More particularly the latch 10 is shown secured to the frame `13 by way of wood screws 15;

The latchingmeans 11 isgrotatably moveable out of locking engagement with the drawer 12 by the application of pressure upon the top of a casing or tube 16 to release, as described in detail here-in-after, `the latching means 11 for movement to a position over the base 14 and away from the drawer 12. The area of upper surface of the tube or casing 16 is purposely made small so as to limit the operation of pressure application to` a single tingen For example thediameter of the upper i Y Lsurfacepreferably is no larger than one inch. Whilean is kept out of the hands of the children and `thefoperation of the hidden or secret fastener takes placeunseen by the children.

The problem of preventing small children from openuse of greater sustained force than the child is capable of applying. Y e

In accordance with the` present invention there is employed a release mechanism operable solely by pressure to be exerted by one finger.

More particularly and in accordance with the present` invention there is provided a latch comprising `a Vfirst cylindrical casing having aslot portion of which extends at least in part peripherally of the casing and having a further portion which extends toward the bottom of the casing. A second cylindrical casing isjmounted coaxially with the first casing and thecasings are rotatably moveable relative to each other. A drawer engaging means is secured to one of the casingsjand extends radially outi Wardly from and moveable wtih the casing from a drawer engaging position to` a drawer disengaging position.

means including the slot is provided for locking the engaging means in the positions. The casings are also moveable axially relative to one another against force exerted by a spring to release the engaging means for Forother objects of the present inventionand attendanty advantage thereof reference may be had "to the fol- Y lowing detailed description taken in conjunction with the v VFig. l isa adult is capablevof applying the sustained pressure necessary to release the' latch a small'child is incapable of applying such force with the one finger by which the applicationof pressuremust be exerted. i `Construction details .of the `latch are illustrated in Fig. 2 wherein the lirst casing or tube 16 is shown mounted coaxiallyor concentrically with a second casing 17.

`cooperating ring 19` secured to the base 14, for example by Way of` rivets 20, and having inwardly disposed flange portion 21 for engagement withthe flange 18 of the `casing 17.1`

,The `latching means 11 is shown forming an integral part "of .thefcasing 17.'` Itis to be understood however that the `latching means or drawer engaging arm 11"may be separately formed and secured to` the casing' as by way ofmachine screws (not shown) or `by'welding the Y engaging arm or latching means 11 to the outside surface r of the `casing 1-7. f It is preferred that the latching means 1 22 formed-of rubber or other resilientmaterialand secured iniany desired manner, for example, as by way of machine screw ,23,` to the underside of the armor latchform an integral part ofthe casing for maximum strength -inasmuch as it is` `contemplated that the drawer 12 will be vigorouslyldrawn against thearm or latching `means 11 byA children attempting to open'it. In this regard, in order to prevent the marring of the finish of the drawer 112,` the latching means` may be provided with a cushion The latching means or ann 11V is maintained in `either including a rod 2.4, a `sleeve V25, aslot 26 formed in the casing 164and a projection or pin 27 extending inwardly Fig. 2 with a portion cut away showing features ofzconfrom the1 inner surface ofthe casing 17. Thegrod 24, shown-as ,integral with thefbase` 14, is provided with at least oneand preferably two projections 23 extending into andf otherwise received by. slots 29 formed in the sleeve L `25 depending from thefunderr surface of the" casing 16.

. i j. i 70` of amodication ofkthe With the "construction thus"?fardescribed and with the A ing the ring to the base.

may be employed or the ring may be welded to the base.

V14 and that its motion is limited to an axial movement relative to the casing 17 against the force of a spring 30. With the projection 27 engaging the walls of the slot 126 theV latching means 11 will belocked in a drawer engaging position until such Vtime as the casing'16 is moved 'axially against-the force of the spring 30 to release and otherwise allow rotation of the latching means 11 to a drawer disengaging position and in a manner now to be described. Y

Referring now to Fig. 3 the slot 26 is shown comprised of at least three portions; a vertical portion 31 extending from the bottom of the casing 16, a horizontal portion 32 and a second vertical portion 33 at the opposite end of kthe horizontal portion 32. The latching means is released when the casing 16, Fig. 2, is lowered to a position wherein the horizontal portion 32 of the slot 26 is opposite lprojection 27. At thatV time the latching means 11 may be rotated freely with the projection 277 riding in thehorizontal slot 32 to a position adjacent the slot 33.

-Now upon release of pressure from the top of the casing 16 the spring 30 Vwill move the casing upwardly and the projection 27 will ride in the slot 33 to the lower portion thereof to lock the latching means 11 in drawer disengaging position.

lthe latching means to proper locking relation with the :drawer at which time the projection 27 will enter slot-31.

Under inuence o-f spring 3i) thev projection 27 is guided relative to casing 17 and along slot 31 to lock the latch- V ing means in a drawer engaging position.

With the latching means 11 in drawer engaging position the upward movement of casing 16, as caused byspring 39, is limited by ,means'rincluding a shoulder 34 Vat least in part peripherally formed about the bottom portion of the casing 16 and a sleeve 35 threadably mounted on the casing 17 and having an inwardly disposed flange ,36 engaging the shoulder 24.

While the ring 19 mounting the casing 17 to the base 14 has been described as riveted to the base Vit will be understood that other means can be employed for secur- For example machine screws ln a preferred embodiment-the ring 19 isforrned in two pieces in order to facilitate assembly ofthe latching"Y mechanism.

A wide choice of materials known to those skilledl in the art are available for construction of the latch mechanism of the present invention. The spring should be of durable spring-steel having, when formed, a compliance which will defy compression of the spring by small children seeking'to release the latch. The latch of the present invention, as above described, will provide a latching means of small size and of simple operation yetV will be n effective to keep materials harmful to children readily accessible for considered use by adults and out of the Yhands of children,V

Now that one embodiment has been fully described otherembOdimentS', all within the 'scope of the'present 12.,."111 Fig. 3a there is illustrated a y*modification in which the depression'of the casing 16 automatically will rotate'the' latching means into and, out of engagement -with the vdrawer 12 thus providing one-finger operation fof the latch', More particularly Ysuch operation is provided by providing a slot' 0in a form of helixhavingan open f end at the bottom of a casing 16ifand having a'vertically rdepending lslotted -portion M4-'The' portion 41 functions in a manner similar to the slotted portion 33 of Fig. 3 in order to provide a locking of the latching means in a drawer disengaging position. The locking of the latching means in a drawer engaging position is provided by a short portion 42 of the slot 4t) being substantially vertical such that the casing 16a will have to be moved a short vertical distance before rotationof the latching means commences. In operation the depression of the casing 16a will cause the walls of slot 40 to apply a force to the projection 27, Fig. 2, which force will be translated into a rotation of the latching means as the projection 27 continues to ride along the walls of slot 40. .j

Yet another modification of the present invention /is illustrated in Fig. V4 wherein a latching means 11b is shown forming an integral part of the first or outer casing 16b `and in which the slots, which cooperate with arprojection to provide the locking of the latch means in drawer engaging and drawer disengaging position, are formed` provide a rough surface for ease of transmitting rotational motion from the finger to the casing.

One arrangement of slots suitable for use in the modification in Fig. 4 is illustrated in perspective .in Fig. 5. The slots include a first vertical portion Sib, a horizontal portion 32h and, at an opposite end of the horizontal portion, a substantially vertical depending portion 3.3i). These slotted portions cooperate in the same Vmanner as the portions 31-33 of Fig. 3 to provide in part a'means forlocking, releasing and for moving the latching means between two selected positions. shorter slot portion 31b locks the latching means in a drawer 'disengaging position while the longer slotted portion 3319 locks the latching means in a drawer engaging position. While both the slot 31b and 33h may be of the same size it is preferred to make the slot 33h deeper in order to require a sustained Vforce of relatively long duration for releasing the latching means from a drawer engag-Y ing position. Thus while a child mayhave sufficient strength to begin release of the` latch he will be unable to sustain the pressure required to complete the release vided for the ready assembly ofthe component parts of the latching mechanism. In such assembly the upper or outer casing leb is mountedoverthe casing 17h w1th theextension 27h within the slot 47. Pressure is applied i to the top of the casing 16h and against the force of the spring Stib to move the extension or extending portion 27b along the slots 47, i6 and 45 to a position where the extending portion is received by the slot 3J). Y

While the various embodiments ofthe present Yinvention have `been illustrated as mounted on a frame adjacent a drawer as by way of base v14 it will be understood that whenthe construction ofthe door ordrawer dictates adapters -may be employed for proper mounting of the latch mechanism. f

Y Nowl that the invention has been described and several modifications set forth it will be apparentthat `stillfurther modifications willsuggest themselvesto those skilled in the art and it is intended to cover such modifications by'the appended claims.:l

What isclairned is:

f A latchfcomprising a first. cylindrical casingwhaving a slot including a portion extending at least in part pe- More particularly the ripherally thereof and having a further slotted portion extending toward the bottom of said casing, a second cylindrical casing mounted coaxially with said first casing and having a first projection extending into said slot, a base for mounting to a xed surface adjacent the edge of a drawer, a vertically extending rod secured to said base and having a second projection intermediate its ends extending outwardly, a sleeve depending from one of said casings for receiving said rod, said sleeve having at least one vertical slot into which said second projection extends for locking said one of said casings against rotation relative to said base, the other of said casings being rotatably mounted to said base, drawer engaging means secured to said other of said casings and extending radially outward from and moveable with said other of said casings between a drawer engaging position and a drawer disengaging position, means including said rstmentioned slot and said rst projection extending into said further slotted portion for locking said drawer engaging means in said positions, said casings being axially moveable relative to one another to position said iirst projection into said peripheral portion of said slot for releasing said drawer engaging means for movement between said positions, and a spring for normally urging said casings apart.

2. A latch as in claim l in which said one of said casings is provided with a shoulder portion extending at least in part around circumference thereof and in which said other of said casings is provided with an inwardly disposed flange for engagement with said shoulder portion to limit the axial movement of said one of said casings in a direction away from said base.

3. The latch of claim 1 in which said one of said casings is provided with a top surface to which force may be applied to move said one of said casings downwardly to release said drawer engaging means for movement be tween said positions.

4. A latch mechanism for a drawer and adapted for mounting on a surface adjacent to and fixed relative to the drawer comprising a base for mounting to the surface, an outer cylindrical casing, an inner cylindrical casing mounted in telescoping relation with said first casing and having an end extending `above said rst casing, one of said casings being mounted at one end thereof to said base, a drawer-front engaging arm mounted on and intermediate the ends of said outer casing, said arm being moveable about said inner casing between a drawer-engaging position and a drawer-disengaging position, means on said inner casing for locking said arm in either of said positions, and means at the top of one of said casings for moving said one of said casings downward to release said arm for movement between said positions.

5. A latch assembly for a drawer and adapted for mounting on a surface adjacent to and fixed relative to the drawer comprising a base for mounting to the surface, an outer cylindrical casing mounted at one end thereof on said base, an inner cylindrical casing mounted in telescoping relation with said outer casing and having an end extending above said outer casing, a drawerfront engaging arm mounted on said outer casing and normally positioned intermediate the ends of the assembly, said arm being moveable about said inner casing between a drawer-engaging position and a drawer-disengaging position, means on said inner casing for locking said arm in either of said positions, and means at -the top of said inner casing for moving said inner casing downward to release said arm for movement between said positions.

6. A latch comprising an inner cylindrical casing having a slot including a portion extending at least in part peripherally thereof and having a further slotted portion extending toward one end of said inner casing, an outer cylindrical casing mounted coaxially with said inner casing and having a projection extending into said slot, a base mounted to one end of one of said casings for securing the latch to a xed surface adjacent a surface moveable with respect thereto, said casings being rotatably moveable relative to each other, means for engaging the moveable surface and secured to said outer casing, said engaging means being moveable with said outer casing from a moveable surface engaging position to a moveable surface disengaging position, means including said slot and said projection extending into said further slotted portion lfor locking said engaging means in said surface engaging position, said casings being axially moveable relative to one another to position said projection in said peripheral portion of said slot for releasing said engaging means for movement between said positions, and means normally urging said casings axially apart.

7. A latch as in claim 6 in which said slot is in part a helix and with said projection extending into said helix rotates said outer casing to move said engaging means between said positions as said inner casing is moved axially of said outer casing.

8. A latch as in claim 6 in which said outside vcasing is rotatably mounted to said base.

9. A latch as in claim 8 in which a helical spring within said casings provides said urging means to move said inner casing away from said base to lock said engaging means in said moveable surface engaging position.

References Cited in the tile of this patent UNITED STATES PATENTS 521,341 Gardner June 12, 1894 776,178 Guedeney et al Nov. 29, 1904 948,119 Wettig Feb. 1, 1910 2,051,132 Dart Aug. 1S, 1936 42,276,915 Axe et al Mar. 17, 1942 FOREIGN PATENTS 729.751 France May 2, 1932.