US3014744A

US3014744A - Positive cabinet lock

Info

Publication number: US3014744A
Authority: US
Inventors: Darrel W Craik
Original assignee: Individual
Current assignee: Individual
Priority date: 1959-01-20
Filing date: 1959-01-20
Publication date: 1961-12-26
Anticipated expiration: 1978-12-26

Description

Dec. 26, 1961 D. w. CRAIK 3,014,744

POSITIVE CABINET LOCK Filed Jan. 20, 1959 2 Sheets-Sheet 1 Dec. 26, 1961 D. W. cRAlK POSITIVE CABINET LOCK 2 Sheets-Sheet 2 Filed Jan. 20, 1959 R m E V W .Il lilllill\lllllllli\\ iinited States @arent @ffice lijid Patented Dec. 26, il

3,014,744 PSlTlVE CABENET LUCK Darrel W. Qrailk, 6532 N. Hickory, Escondido, Calif. Filed dan. 20, 1959, Ser. No.. 77,966

2 Claims. ttCl. 292--l7} ll`his invention relates to locks or catches for cabinet doors or other closures.

Cabinet doors in moving vehicles, such as trailers, airplanes, boats and the like, often fly open unless special locking devices are employed. Releases for cabinets out of the reach of children may also be desired so that a pull at the lower edge of the cabinet is ineitective to open the cabinet. For various other reasons, positive locks are often desirable.

Known positive locking devices have serious drawbacks. Usually they require manipulations in addition to the simple pull or push at a door pull; if not unsightly, such known devices are expensive or complex.

The primary object of this invention is to provide an improved positive lock for a cabinet door or the like that is simple and inexpensive.

Another' obiect of this invention is to provide an improved positive lock for a cabinet door or the like in which the lock is released by the very action of pulling the door pull and in which the lock is set automatically by closure of the door or the like.

Still another object of this invention is to provide a positive lock the operative parts of which are virtually concealed. This, together with the single manipulation feature, makes the user actually unaware of the fact that a positive lock is operative.

Yet another object of this invention is to provide a positive lock of this character that is easily and efficiently installed.

Yet another object of this invention is to provide a new positive lock which requires for installation no alterations of the cabinet structure except the provision of a simple through bore in one of the cabinet structure parts.

This invention possesses many other advantages, and has other objects which may be made more clearly apparent from a consideration of several embodiments of the invention. For this purpose, there are shown a few forms in the drawings accompanying and forming part of the present specification. These forms will now be described in detail, illustrating the general principles of the invention; but it is to be understood that this detailed description is not to be taken in a limiting sense, since the scope of the invention is best dened by the appended claims.

Referring to the drawings:

FIGURE 1 illustrates a typical cabinet structure incorporating the present invention;

FIG. 2 is an enlarged fragmentary sectional view, taken along the plane indicated by line 2.--2 of FIG. l, and illustrating the lock structure set in locking position and the corresponding cupboard door closed;

FIG. 3 is an enlarged fragmentary sectional view,

taken along the plane indicated by line 3 3 of PEG. 2;

FIG. 4 is a View similar' to FIG. 2, but illustrating the lock released immediately prior to opening of the cabinet door; i

PEG. 5 is a View similar to FiGS. 2 and 4, but iliustrating the parts after opening movement of the cabinet door;

FIG. 6 is a fragmentary view illustrating a moditied form of the present invention; and

FIG. 7 is a longitudinal sectional view, taken along the plane indicated byline 7-7 of FiG. 6.

ln PEG. l, there is iliustrated a cabinet structure it? having doors l2 and 16 and an intermediate shelf TA. The doors l2 and lo are hinged respectively at the left 2 and right so that tieir outer edges meet at the center when the doors are closed. A lock structure is provided for each door. The shelf i4 serves conveniently and conventionally as a support for one of the two elements of each lock structure.

ri`he details of the lock structure are shown clearly in FIG. 2. A ball head screw l of resilient material is mounted upon the support or shelf 1d so that its ball end 2t) projects forwardly of the vertical surface 1S.

The ball 2@ forms a strike that is releasably held by a keeper or catch 22 mounted upon the door or ciosure i2. The catch 22 is formed as a `generally hollow body, having a recess 23 extending inwardly from one end. The catch is accommodated in a through bore 2li of the cabinet door l2 with its recess 23 facing inwardly. Several exterior thread turns, as at 26, are formed at the outer end of the catch ZZ for engagement with the bore 24, whereby the catch is attached to the door i2 without requiring the catch Z2 to project inwardly beyond the bore 24. The threads have a larger external diameter than the bore 24.

For installation of the catch 22, the end remote from the thread turns is placed in the bore 2.1i until the inner end thread turn engages the edge at the outer side of the door l2. Rotation of the catch 22 now causes the thread turns to form their own channel in the bore 2li of the door i2.

A head 28, adjoining the outer end thread turn, serves as a means for rotating the catch 2?., and as a means for limiting inward movement thereof.

Frictional engagement between the head 28 and the edges about the end of the bore Z4 when the catch is fully inserted restrains angular movement ot the catch ZZ.

The head 2S has a diametric slot whereby it may be engaged by a screwdriver or the like.

The head 2&3 is longitudinally slotted to impart flex-A ibility so that it may be resiliently contracted. It enters the right-hand end of the catch 22. and passes through an opening 3i? that is restricted relative to the head 20 to an area less restricted. Accordingly, the resilience of the head 2d, which resists constriction, causes it to be held at the less restricted area. In the present instance, the relatively restricted lopening and the area of less restriction are provided by a spherical seat 32 in the form of an equatorial Zone that is formed inwardly of the end of the catch bore 2li.

In the present instance, two intersecting slots 3d and 36 divide the head 2t) into quadrants or sections to provide the necessary resilient contraction to pass the restricted opening 3b. When it passes the restricted opening 3d, the head 2t) springs outwardly in order to conform substantially to the spherical seat 32. Desirably the size of the spherical seat 32 is slightly less than the normal size of the head 29. Accordingly, there is a firm. frictional engagement between the parts, and rattles are prevented.

The axial spacing of the head Ztl from the end surface 1S can be adjusted to compensate for the thickness of the door .i2 so that the door is closed when the head 2t? engages the seat 32. lf the door l2 is actually thinner than the length of the catch 22, a counterbore at the shelf may be provided.

To open the door i2, the catch 22 must be separated from the screw strike i8. In order for this to be possible, the head Ztl must be constrieted for passage through the restricted opening Sil. A locking projection or pin 3S normally prevents the constriction of the head 24B so that, until withdrawn, it is impossible to separate the catch 22 v and the strike i8.

A recess 42 is formed centrally of the head 20 (see also FG. 3) prior to the provision of the slots 34- and 356; the recess has a diameter greater than the Width of 3 the slots so that arcs in the inner corners of the quadrant fingers remain. The pin 3S projects into this recess, and ts the four arcs, in order to prevent constriction of the head 20 whenever the pin is in position.

The pin 33 is formed at the end of a plunger that is guided for movement longitudinally in the catch bore recess 23.

The plunger 4G has a reduced stem at that end opposite the pin The plunger passes outwardly through an aperture at the bottom of tho catch bore recess 23, and beyond the catch head A coil spring 52 surrounds the stem 44 in the recess 23 and urges the plunger do toward the inner end of the body L12, and the pin 3S in a direction corre pending to locking relationship with the screw head 20. The bottom Sil of the body recess 23 forms a seat for the spring L12. The limit of inward movement of the plunger' in locked position is determined by engagement of the end surface S6 of the plunger, from which the pin 313 projects, with the end surfaces of the quadrants of the strike head7 as illustrated in FIG. 2.

`The plunger #itl must be retracted against the force ot the spring in order to unlock the catch. A doc-r pull 4 formsthe lock operating member. In' this instance, 'the pull is in the form of a knob mounted upon the projecting end of the plunger 4t?. The knob 54 has a central recess 56 in its base in which thc end of the plunger 40 is received. A set serieul 58, mounted by the base of the knob 54, engages in an annular groove 60 adjacent the end of the plunger 45 to hold the parts togetler. The knob base 55, by engagement with the head 23, limits movement of the plunger 40 under thc inuence of the spring S2 when the catch and strike 'are separated, and prevents separating movement of the plunger fi-0 from the catch body. By pulling the knob 54 outwardly in a direction corresponding to the separating movement of the door l?. and as illustrated in FIG. 4, the pin 38 clears the head recess before the door l2 moves. A continued pull 'Urpn the knob 54 causes the catch 22 to separate from the strike head 2G, as illustrated in FlG. 5.

The force necessary to release the pin 38 is quite slight, especially in comparison to the force necessary to cause constriction of the ball end of the strike 18. The user actually does not recognize that his pull is effective in two steps to accomplish the two functions in sequence.

To cause the lock to be operative, it is only necessary to close the door by any means, such as by a push anywhere on the door. It is unnecessary to manipulate the knob 54. The strike head 29 is partially constricted and has partially entered the restricted opening 30 before the pin is engaged. It is vital that this be the case; otherwise, necessary further constriction of the head would be precluded, and the lock would jam. Advance constriction of the head accomplishes this result, for now the opening 42 is restricted and the pin 38 cannot enter. Accordingly, the pin 3S and plunger 40 are pushed in advance of the head 20 until the recess 4.2 enlarges sufciently to permit the pin to enter therein. This occurs only when the head 20 expands to engage the seat 32. Accordingly, locking occurs automatically after the catch and strike are engaged.

ln FIGS. 6 and 7, there is illustrated an alternate door pull arrangement utilizing a handle 7G. The handle has one end alixed to the door, as by a screw 72. The other end of the handle has a bifurcated end 74 which fits within the annular groove oil of the plunger stem 454. To release the lock, two or three vlingers enter behind the i andle and an outward pull causes the pin first to be removed from locking position, and then the catch and door move in unison away from the strike.

ln any event, the positive lock structure is inconspicuous. lt is substantially hidden behind the door pull 54 in the form illustrated in FlGS. 1 to 5 or the handle 7) in the form illustrated in FIGS. 6 and 7. The door pull attached to the plunger 40 lies about as close to the door proper as a conventional pull. These factors, plus the virtual single manipulation, combine to produce an effective positive lock of which the user is unaware. The installation of the catch body Z2 is no more diicult than the installation of a conventional door pull; since the present structure substitutes for the usual door'pull, no additional installation time is required.

Of course, vibrations and other forces exerted upon the door 12 will not be effective to retract the pin 33; hence, the door cannot be opened except by pulling the knob 54. It is possible to utilize this device in a cabinet the doors of which are hinged on non-vertical axes, or on closures guided for other than horizontal movement.

The inventor claims:

1. In a positive lock structure: a hollow body adapted to project into a through bore in a first cabinet structure, and having an inner end and an outer end; said hollow body having screw-threaded provisions for attachment to a through bore in the cabinet structure, including a head at the outer end providing a shoulder for engaging the edges about the bore; said body having a substantially cylindrical recess extending from the inner end of the body, and an aperture extending through the bottom of the recess at the outer end of the body; the body having an interior groove adjacent the inner end thereof; a round-head screw of resilient material adapted to be mounted on a second cabinet part, the head of the screw being slotted to impart flexibility to head sections thus formed; the screw head being entrance into the recess at the inner end of said body for cooperation with said interior groove; a plunger guided by the body in the recess, and having a stem projecting through said aperture; said plunger having a projection capable of entrance between the screw head sections to prevent exure thereof adequate to permit disengagement from said body; a coil spring in the bottom of the body recess and urging the plunger toward the inner end of the body; and a lock operating member detachably affixed to the outer end of the stem and engageable with the body head to prevent separating movement of the plunger from the body.

2. The combination as set forth in claim l, in which said attachment provisions of the body comprise peripherally formed wood screw threads adjacent the body head, whereby the inner end of the body need not project beyond the edge of the cabinet Structure.

References Cited in the le of this patent UNITED STATES PATENTS 289,666 Lee Dec. 4, 1883 661,460 Tefft et al. Nov. 6, 1900 861,526 Little July 30, 1907 1,300,579 Carr Apr. 15, 1919 1,647,780 Carr Nov. 1, 1927 1,866,326 Stevens July 5, 1932 2,480,662 Mclinzie Aug. 30, 1949 2,807,489 Adams Sept. 24, 1957 FORETGN PATENTS 677,438 Germany June 26, 1939 capable by flexure of-