Latch mechanism

June 24, 1969 c. _{H L},_TTLE 3,451,702

LATCH MECHANISM

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June 24, 1969

C. H. LITTLE

3,451,702

LATCH MECHANISM

Filed March 14, 1967

Sheet 2 of 2

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ATTORNEYS

United States Patent Office

3,451,702

Patented June 24, 1969

FIG. 5 is a fragmentary sectional view taken as suggested by line 5—5 of FIG. 2;

FIG. 6 is a disassembled perspective view of the latch mechanism housing portion of the device;

FIG. 7 is a fragmentary front elevational view of a vertically standing cabinet having a horizontally swinging door controlled by a latch mechanism of the present invention; and

FIG. 8 is an enlarged scale fragmentary sectional view taken as indicated by line 8—8 of FIG. 7.

Detailed description

As shown by way of example at FIG. 1 in the drawing herewith, the invention is adapted to be applied to a cabinet structure including a front wall 10; a rear wall 12; and a top cover or lid 14; the lid 14 being hingedly mounted by means of a hinged device 15 to a rear sill portion 16 of the cabinet structure so that when the cover is down in cabinet-closing position its tip surface is flush with the top surfaces of the cabinet members 10, 16 A spring device as indicated at 18 (FIG. 1) is provided to overcome the weight of the cover 14 and to cause it to rise into cabinet-opening position whenever the strike 20 is released from the latch mechanism which is indicated generally at 22. However, it is to be understood that the latch mechanism of the invention may be employed in connection with a large variety of other forms of cabinet and. door-cover structures, as well as in connection with swinging doors or the like as illustrated at ₃₀ FIGS. 7, 8, herein. Also it is to be understood that the spring-opening effect of the cover or door member may be attained through use of any other suitable form of spring or gravity or other power supply device in lieu of the form of spring device 18 of FIG. 1 or of the form 35 of spring device which is shown in FIG. 8 and which will be more fully described hereinafter

As illustrated at FIGS. 1-5, the latch mechanism of the present invention includes, in combination, a special form of strike device which is indicated generally at 20 40 and comprises a base portion 24 adapted to be fastened as by means, of screws or the like to the cover member 14 as shown m FIG. 1. The strike blade is indicated at 26 and terminates in a cam-shaped nose portion 28 formed to include a laterally extending jaw portion 29, and at its opposite side it is formed to include a laterally extending heel portion 30. ^s

The latch mechanism 22 includes a housing portion 32 which is in the form of a box shaped sheet metal stamping having flange portions 34—34 at opposite ends thereof for mounting the housing against the inside wall portion of the cabinet structure 10, as by means of screws or the like as illustrated at 36 herein. As shown in better detail in FIG. 6, the housing member 32 is apertured as indicated at 38 to accommodate passage therethrough of the strike member 20 when the cover member .14 is moving between cabinet-opening and closing positions. Also, the front wall portion of the housing member 32 is die-stamped to project inwardly therefrom a pair of right-angle extending lug portions 39__39 upon which are subsequently slip-fitted a pair of cushion sleeves 40—40 formed of any suitable rubber or plastic material or the like, for purposes to be explained hereinafter.

The latch device per se of the present invention comprises a rocker member 44 which is pivotably mounted upon the side wall portion of the housing by means of a pivot device designated 46. The rocker member 44 includes at one end a laterally extending latch arm portion . terminating in a hook end portion 50 which is so dis70 posed as to be directionally aligned with movements of the nose portion 28 of the strike member as the latter moves in accordance with opening and closing of the

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LATCH MECHANISM

Carl H. Little, Jamestown, N.Y., assignor to Weber-Knapp Company, Jamestown, N.Y. Filed Mar. 14, 1967, Ser. No. 623,033 ITS ^In£^CLE05c 19/10;E05f 1/00

U.S. Cl. 292—99 4 ci_aj_ms

ABSTRACT OF THE DISCLOSURE

An improved automatic latch, for hingedly mounted doors or covers or lids for cabinets or the like. The latch operates automatically to secure the door or cover upon pressing it into closed position, and releases when the door or cover is subsequently pushed against, thus permitting the latter to swing open under the impetus of an auxiliary spring or the like. The invention features an improved mechanism as aforesaid which is mechanically simplified, non-locking in event of mechanical failure· and which provides long-life improved ease and smoothness of operation.

Brief summary and background of the invention

Prior forms of such latches have proven to be somewhat unsatisfactory and unreliable in operation, either because of failure to properly secure the door in closed position or to, freely release it when desired. Also such prior latch constructions are unsatisfactory because of mechanical complications involved in their designs, and because of the costs necessarily involved in the manufacture and assembly of their parts.

. It is an object of the present invention to provide an improved latch of the type aforesaid which is of mechanically simplified form and which may be relatively inexpensively manufactured to provide a smooth-working reliable, automatic latch mechanism.

. It is another object of the invention to provide an improved latch mechanism as aforesaid wherein the parts are so arranged that in the event of mechanical failure of any part or parts the mechanism will not remain in locked condition.

Still another object is to provide a mechanism as aforesaid wherein the slide-bearing relatively moving parts are of materials providing long-life frictionless operation, whereby smooth working and maintenance-free performance is assured.

Other objects and advantages of the invention will be apparent from the following specification and the accompanying drawing.

In the drawing:

FIG. 1 is a fragmentary vertical sectional view through a cabinet having a vertically swinging cover hingedly 55 mounted thereon, and embodying an automatic latch mechanism of the present invention;

FIG 2 is a fragmentary sectional view taken as indicated by line 2—2 of FIG. 1; illustrating by means of broken lines the positions of the latch parts when the cover is being pressed downwardly toward cabinet closing position; and by means of solid lines showing the parts when in cover-holding position;

FIG. 3 corresponds to FIG. 2 but illustrates coaction between the latch parts when the cover is subsequently further depressed to disengage the latch parts; ⁶⁵

FIG. 4 corresponds to FIG. 3 but illustrates how (when th! ι^^νι!^Γ/·ν^{β8 m res}P°?^{se to the} spring-hinge action) the latch strike resets the latch mechanism to subsequently receive the strike for automatically latching the cover ,, when it is again pressed down into cabinet-closing posi- ⁷

3,451,702 cabinet structure, while permitting it to be slightly depressed for subsequent release and opening of the lid.

FIGS. 7, 8, illustrate application of a modified form of the device of the invention in conjunction with a vertically standing cabinet structure which is indicated generally at 60 and upon which is hingedly connected as indicated at 62—62 a horizontally swinging door panel 64. An automatic latch mechanism of the invention is shown as being mounted in connection therewith to comprise a strike member 20 as described hereinabove and a latch mechanism 22 of generally similar construction. However, in the case of FIG. 8 the housing member 32 is illustrated to include a slidably mounted plunger 66 which is resiliently biased by means of a compression spring 68 to extend forwardly of the edge-view profile of the cabinet structure.

Hence, whenever the door member 64 is pressed further inwardly beyond cabinet closing position as explained hereinabove, the plunger 66 will be thereby depressed against the action of the spring 68 as the rocker member 44 of the latch mechanism operates to engage the strike 20 in holding relation. Then, upon subsequent further manual depression of the door panel 64 against the latch mechanism and release of the strike member as explained hereinabove, the spring 68 operates to give the door an outwardly moving impetus. Thus an alternative to the spring device 18 hereinabove referred to is provided as an integral part of the latch mechanism per se.

It is a particular feature of the present invention that as shown herein the rocker member 44 is preferably made of some material possessing the so-called “self-lubricating” or “frictionless” characteristic, and it is also preferable to make the rocker of some plastic material having the sorms osiuoii ui mt &lt;in- iuv pu.r-.K.v __ called “elastic memory” characteristic. Suitable materials

Ms ^eTn^arried tTthTleft aToss thT^center’ofThTpivot 35 for this purpose are known in the trade for example as xamu — ΤΆ-Ι»-!— ,-,.-.,4 +L-, Τ.ν» TRa n+rilza rviamkar ΉΙ nnrl ³ cover member 14. The hook portion 50 of the rocker member is of rounded external form, so that whenever the nose portion 28 of the strike member 20 comes into bearing relation against the external surface of the latch portion 50 the latter is thereby cammed aside, causing the rocker member 44 to pivot in counter-clockwise direction as viewed in FIGS. 2-4 herewith. A tension spring as indicated at 52 is connected as indicated at 53 to one arm portion of the rocker member 44 and is anchored at its other end as indicated at 54 to the housing member.

The parts are so arranged that when the rocker member 44 is in strike-holding position as shown in FIG. 2, the spring 52 is operating to hold the rocker member in strike holding position. Also, the parts are so arranged that when the rocker member is thus operating in strikeholding position the cover member 14 is disposed so that its upper surface is flush with the top surfaces of the front, side, and back wall portions of the cabinet structure. The relatively movable parts are directionally aligned so that when the cover member 14 is subsequently further depressed beyond the cabinet-closing position referred to, the nose portion 28 of the strike member bears inwardly against an abutment portion 56 of the rocker member 44 which is eccentrically displaced from the axis of the pivotal connection device 46.

Therefore, assuming the mechanism to have been previously shifted to cover-holding position as shown in FIG. 2 herewith, upon subsequent further depression of the cover member as illustrated by FIG. 3, the nose portion 28 of the strike member bears against the abutment portion 56 of the rocker member so as to cam the latter against the action of the spring 52 in counter-clockwise direction and into the attitude illustrated by FIG.. 3. In this position of the parts the pull-line of the spring 52 axis of the device 46; and therefore the rocker member 44 is now held in the attitude shown in FIG. 3, whereby the strike member 20 is fully released from its previous engagement with the hook portion 50 of the rocker memL„. /-- - ' ’“^J swing open under the impetus of the spring device as indicated at 18.

It is also an essential feature of the mechanism of the invention that the rocker member 44 carries at its opposite end a flange portion 58 which is shaped to cam- 45 wise engage with the heel portion 30 of the strike member 20 whenever the latter moves outwardly of the latch mechanism housing as explained hereinabove. As illustrated by FIG. 4, this camming action of the strike member against the flange portion 58 of the rocker member 50 causes it to pivot in clockwise direction so as to free the strike member totally from engagement with the rocker member, while at the same time disposing the latter so that the line of pull of the spring 52 has been shifted back to the right beyond the axis of the pivot de- 55 vice 46. The parts are so shaped that as the heel 30 of the strike cams the flange portion 58 of the rocker in clockwise direction the hook portion 50 of the rocker comes back against the strike below the level of the jaw wiJivivci.y ------_r- ------ ---Hence, the rocker member will now be pulled back down into the attitude illustrated at FIG. 2 in preparation for a subsequent reception of the strike member in cover holding position as illustrated at FIG. 2. It will of course l____________:. ’ positioned as to appropriately limit the back and forth rocking movements of the member 44 as explained hereinabove.

Whereas FIGS. 1-3 illustrate the cabinet to be of the

Delrin, nylon, and the like. The strike member 20 and the pivot member 46 for the rocker 44 may then be made of steel or any other suitable metal, whereby the rocker 1 in wiiii me ______________ member may be said to be frictionally compatible relabel Therefore,TheTovePmember TTTs nowTeieased’to ⁴θ tive to its pivot connection and to the strike 20. Hence, * ⁵ - - . , · · ύτιΤιλλ +Ιλλ Ιηιτιατ· an/1 z-\+ fka rfrilzo rXAnrc ΖΊ ΖΛΧΤ/ΪΊXT7ΟΓΠIΊ7 1Π when the lower end of the strike bears downwardly in sliding relation against the abutment portion 56 of the rocker as shown in FIG. 3 of the drawing herewith, it slides easily against the rocker abutment and avoids any frictional “seizing” or galling thereof. Also, the rocker freely pivots on the device 46, whereby it will be appreciated that long-life smooth operation of the mechanism is assured. Furthermore, in the event of any abuse of the mechanism such as by slamming of the lid 14 down into closed position or any other action causing inordinate pounding of the strike against the rocker such as may cause momentary plastic deformation of the abutment portion 56, such distortion of the part will be erased by virtue of the elastic memory characteristic of the material. The abutment portion 56 will be immediately restored to its proper cam shape, and hence no permanent deformation or breakage of the parts is experienced.

Also by way of further example, Delrin possesses fric____________________ - tional characteristics such that the static or “starting” Μ, whereby The strike is free to escape from the latch. 60 friction coefficient is virtually the same as the dynamic ’ - - ..... j----- _or “_runnj_ng” friction coefficient. Therefore the latch mechanism of the present invention responds smoothly and in uniform manner to any kind of manually applied ________—___________________ latch-release force, whether it be a deliberate pressure, or be understood that the cushion-stop devices 40-40 are so 65 a sharp blow. This superior performance of the mecha'........ nism continues indefinitely due to the fact that the pivot needs no lubrication, nor do the relatively moving parts 28, 56 and 30, 58, respectively, as they meet in . - __________ ____ sliding contact relation. Alternatively, the strike 20 may “flush” lid type, the cabinet may be of any other styl- 70 be formed of Delrin or the like, while the rocker 44 is ing, such as for’example so that the lid 14 is not recessed .....

relative to the side walls, but extends above or overhangs the side walls when in cabinet-closing position. In any case the latch parts will of course be arranged so as to hold the lid 14 at the desired position relative to the formed of steel or some other metal, whereby the frictionless characteristics hereinabove referred to may be attained. Also, it will of course be appreciated that rollers or the like may be carried by the strike and rocker parts at strategic points of the mechanism if it is preferred to

3,451,702 ⁵ provide for roller bearing contacts instead of slide bearing contacts between the parts.

It will be apparent from examination of the drawing herewith that in event of mechanical failure of any of the parts of the latch mechanism, such as for example failure of the spring 52 or breakage of its connections or of the pivot pin 46 or the like, the parts will automatically fall into strike releasing positions and cannot possibly jam the.strike.against escape from the mechanism. Hence, the cabinet will not become locked in cover-closed position to. the annoyance or other disadvantage to the user.

It will of course be understood that whereas only a few forms of the invention have been illustrated and described hereinabove, various changes may be made therein without departing from the spirit of the invention or 15 the scope of the following claims.