US2968506A

US2968506A - Latch mechanism

Info

Publication number: US2968506A
Application number: US761859A
Authority: US
Inventors: Karl H Lade
Original assignee: JOHN M DOESS
Current assignee: JOHN M DOESS
Priority date: 1958-09-18
Filing date: 1958-09-18
Publication date: 1961-01-17
Anticipated expiration: 1978-01-17

Description

Jan. 17, 1961 K. H. LADE LATCH MECHANISM 4 Sheets-Sheet 1 Filed Sept. 18, 1958 "Jill bL| INVENTOR. XAFL H Z/lfif ATTOKA/EX Jan.

Filed Sept. 18, 1958 K. H. LADE LATCH MECHANISM 4 Sheets-Sheet 2 Jan. 17, 1961 K. H. LADE LATCH MECHANISM 4 Sheets-Sheet 3 Filed Sept. 18, 1958 INVENTOR. KAAZ H Z4D 040% Jan. 17, 1961 Filed Sept. 18, 1958 K. H. LADE LATCH MECHANISM 4 Sheets-Sheet 4 flyjd INVENTOR. KAtL H 1/10;

United States Patent The doors of walk-in refrigerators and other enclosures must be kept tightly closed at all times and, for obvious reasons, such doors must be capable of being opened from within the enclosure. A satisfactory latch of this type is shown in Patent No. 1,752,131 issued to G. P. Wild on March 25, 1930.

One object of the invention is to produce an improved latch mechanism of this type.

A further object is to produce an improved latch mechanism of the type set forth which is also capable of being opened from the inside even when the latch mechanism is locked and cannot be opened from the outside.

As far as I am aware, doors of the type referred to have been provided with a single latch mechanism located substantially midway of the height of the door opening. Such an arrangement is satisfactory when used on a relatively small door. But, in the case of a relatively large door, the upper and lower corners of the door were not closed sufficiently tightly and, in time, the door tended to warp. This disadvantage increased with the increase in the vertical dimension of the door opening. Nor is it practical to provide two or more vertically spaced, individually operable, latches because it would be necessary separately to operate each of said latches every time the door is opened and closed. Furthermore, a latch mechanism placed near the upper edge of a relatively large door will be inaccessible from the floor without the use of a stool or ladder which has heretofore made the use of multiple latch mechanisms still more impracticable.

It is therefore a still further object of the invention to produce a multiple latch mechanism which includes an upper unit and a lower unit for acting on the upper and lower portions of the door, with, or without, a unit for acting on an intermediate portion of the door.

A still further object is to produce a latch mechanism which embodies the improvements referred to, but which is durable and easy to make, install and operate and one which is tamper proof.

A still further object of the invention is to produce an improved latch mechanism, the cooperating parts of which can be readily assembled to form a single unit for acting on a single portion of the door and which can also be readily assembled to produce a multiple latch mechanism including two, or three units for acting on the top and bottom portions of the door alone, or on the upper, lower and central portions of the door simultaneously.

The full nature of the invention will be understood from the following specification and the accompanying drawings in which Fig. 1 is a front elevational view of a door provided with one latch mechanism embodying the invention.

Fig. 2 is an enlarged sectional view taken on line 2-2 on Fig. 1.

Fig. 3 is a much enlarged view partly in front elevation and partly in vertical section showing various parts of the latch mechanism.

Fig. 4 is a sectional view taken on line -,4 on Fig. 3. Fig. 5 is a sectional View taken on line 5-5 on Fig. 3. Fig. 6 is a sectional view taken on line 6-6 on Fig. 3. Fig. 7 is a sectional view taken on line 7-7 on Fig. 3. Fig. 8 is a sectional view taken on line 8-8 on Fig. 3. Fig. 9 is a front elevation view of a multiple latch mechanism which also includes upper and lower units which act on the top and bottom corners of the door and which are operated simultaneously with the operation of the unit which acts on the center portion of the door.

Fig. 10 is a sectional view taken on line 10-10 on Fig. 9.

Fig. 11 is a sectional view taken on line 11-11 on Fig. 9.

Fig. 12 is similar to Fig. 3, but shows an embodiment of the invention in which the latch mechanism also acts on the top and bottom portions of the door.

Fig. 13 is a sectional view taken on line 13-13 on Fig. 12.

Fig. 14 is a sectional view taken on line 14-14 on Fig. 12.

Fig. 15 is a sectional view taken on line 15-15 on Fig. 12.

Fig. 16 is a sectional view taken on line 16-16 on Fig. 12.

Fig. 17 is a sectional view taken on line 17-17 on Fig. 12.

Fig. 18 is a sectional view taken on line 18-18 on Fig. 9.

The embodiment illustrated in Fig. 1 includes a door frame 10 provided with an opening adapted to be closed by a door 12, mounted on hinges 14.

The door is provided with a substantially centrally located latch mechanism, one part of which is carried by the door frame and the other part of which is carried by the door. The part of the latch mechanism carried by the door frame includes a housing 16 which is suitably secured to the door frame adjacent the free edge of the door and encloses a tongue 18 which is normally biased by a spring 20 to the right, as viewed in Figs. 1, 2 and 4, or into engagement with the edge of the door to prevent opening of the door as hereinafter more fully explained.

The part of the latch mechanism which is carried by the door includes a casting 22 which is suitably secured to the door by screws 23, or the like, and which carries spaced, vertically aligning, pairs of

bosses

24 and 26, and 28 and 30. Also can-ied by casting 22, or by door 12, is an arm 32 which is provided with a flat outer surface 34, which is engaged by tongue 18 when the door is closed, and also with an inner cam surface 38 which rides on the cam surface of tongue 18 during the closing of the door.

Bosses 28 and 30 have registering openings therein for receiving pivot pin 38 on the upper portion of which, as viewed in Figs. 1 and 2, is pivoted the front end 49 of an operating handle 42. Also pivoted on the lower portion of pin 38 is a lever 44, one end of which is provided with a cam surface 46, which coacts with the cam surface of tongue 18 and the other end of which is provided with an upward extension 48 which abuts or is located in the path of movement of, handle 42 as best shown in Figs. 4 and 5. By this arrangement, rotation of handle 42 in clockwise direction, as viewed in Fig. 2, or toward the operator as viewed in Figs. 1 and 3, will rotate lever 44 on pivot pin 38 clockwise direction, as viewed in Fig. 4 to push tongue 18 out of the way, or to the position shown in Fig. 2, in which the door can be opened.

In order to prevent unauthorized opening of the door, a pin 50 is inserted through the openings in the

bosses

24 and 26, and its lower end is engaged by the padlock '52, Fig. 3. In this position, pin 50 will abut the outer surface of handle 42 and will prevent movement thereof in door opening direction, Fig. 2.

In order to prevent tampering, I enclose the parts of the latch mechanism carried by the door with a cover 54; I provide the upper and lower walls of the cover with openings 55 which register with the openings in

bosses

24 and 26, and I pass pin 50 through the openings 55 and through the openings in

bosses

24 and 26 before applying the padlock, as best shown in Figs. 3 and 8. By this arrangement, pin 50 locks cover 54 and prevents movement of handle 42..

In order to permit opening the door from within, I provide pin 56 which passes-through an opening in the door to engage the end 57 of lever 44 and rotate it in door-opening, direction, It will be noted that lever 44 is rotatable independently of handle 42 so that, by means of pin 56, the door can be opened even when padlock 52 is in position and handle 42 is fully immobilized.

The embodiment of Fig, 9 includes top and bottom latch mechanisms which may be used in addition to, or in lieu of, the central latch mechanism of Fig. 1. The top and bottom latch mechanisms are identical and therefore a description of the structure of either of them will sufiice. Also, in describing, the embodiment of Fig, 9, only such parts thereof as are not present in the embodiment of Fig. 1 willv be referred to by new reference numerals. All other parts will be designated by the prime of the numerals. used in describing the embodiment of Fig. 1.

As best shown inFig. 18, each of the top and lower corner latch mechanisms includes a tongue 18' carried by door frame 10" and remotely operable actuating means for pushing tongue 18' out of the way to permit opening of the door. The actuating means referred to includes a pin 60 which is freely slidable in openings formed in bosses 62 and is normally biased away from tongue 18 by a spring 64. Bosses62 are carried by. a casting 22 which corresponds to casting 22.

Pin 60 is urged into engagement with tongue 18 by means of a finger 66 which is keyed at 68 to rod 70 whereby rotation of rod 70 in clockwise direction, as viewed in Fig. 18, will rotate finger 66 into engagement with pin 60. Rotation offinger 66 causes pin 60 to push tongue, 18', out of engagement with the door. Rod 70 may be an extension of pivot pin 38 of Fig. 2, or itmay be a separatepiece keyed to pin 38 as at 72, Fig. 15. It is merely necessary that lower rod 70 and its counter part, upper rod 7 4, rotate upon rotation of pivot pin 38 which, in turn, may be moved by handle 42' fromwithout, or by release pin 56 from within the enclosure.

To present unauthorized opening of the upper and lower latches by rotation of

rods

70 and 74 by means of a wrench, or the like I enclose said rods with freely rotating tubes 76 as best shown in Figs. 9 and 15. The other parts of the upper and lower latch mechanisms are protected against tampering by covers 54 and padlocks 52 or otherwise.

Release pins 56 and 56? are provided with lever operating handles 78 and 78' to provide the mechanical advantage needed to overcome inertia and friction.

In both embodiments, levers'44 and 44 are biased to the positions of Figs. and ,13 by springs 80 and 80' respectively.

The operation is as follows:

Rotation-of lever 44, by handle 42 or by release pin 56,

disengages the central latch mechanism, and in the absence of the top and bottom latch mechanisms, the door can be opened.

When the installations include upper and/ or lower latch mechanisms, rotation of lever '44 also rotates upper and/ or lower rod and 74 to rotate fingers 66 and push the corresponding tongues 18 out of engagement with the door.

In order to make the parts interchangeable, lever 44 is keyed to pivot pin 38 so that this sub-assembly can be used interchangeably in both embodiments.

If it is desired to omit the central latch mechanism, it is merely necessary to omit tongue 18, casing 16 and to close end of casing 54 which faces frame 10.

It will thus be seen that I have provided a latch mechanism which can be used to lock the central portion of the door or which, by adding

rods

70 and 74 and the upper and lower latch mechanisms, can be used to lock the door at two or more points and that the upper and lower latch mechanisms are operated from the central latch mechanism which is readily accessible from the floor.

What I claim is:

1. A latch releasing mechanism for a latch carried by the jamb of a door, said latch releasing mechanism comprising a horizontally disposed tongue carried by the vertical frame which defines the door opening, means biasing said tongue to a first position in which it overlaps the adjacent edge of said door to prevent opening of said door and actuating means for moving said tongue to a second position in which it is out of engagement with and permits the opening of said door, said actuating mechanism including a pivot carried by said door near said edge, a horizontally disposed lever carried by said pivot with one end thereof engageable with said tongue and operable upon rotation on said pivot to move said tongue to its second position, a handle having one end thereof carried by said pivot with a portion of said handle located between the other end of said lever and said door, whereby rotation of said handle in one direction about said pivot engages said portion of said handle with said other end of said lever to rotate said lever in a direction to move said tongue to its second position, and means operable from the other side of said door for rotating said lever in said direction independently of said handle.

2. The structure recited in claim 1 and a second tongue mounted adjacent another portion of the edge of the door, said second tongue being substantially identical with said first tongue in structure and in operation, a pin mounted in alignment with said second tongue and movable into and out of engagement with said second tongue, means normally biasing said pin out of engagement with said second tongue, a cam engageable with said pin and operable, upon being rotated to engage said pin with said second tongue to move said second tongue out of engagement with said door, a rod for rotating said cam, means connecting said rod to said pivot, and a sleeve enclosing said rod" and freely rotatable relative thereto to prevent rotation of said rod except by said pivot.

References Cited in the file of this patent UNITED STATES PATENTS 1,637,168 Wild July 26, 1927 2,043,787 Wild June 9, 1936 2,631,052 Jamison Mar. 10, 1953 2,655,395 Groeger Oct. 13, 1953 2,680,638 Groeger June8, 1954 2,855,771 Berkowitz Oct. 14, 1958