US2639182A

US2639182A - Latch mechanism

Info

Publication number: US2639182A
Application number: US78576A
Authority: US
Inventors: Edwin B Jacobson
Original assignee: CRAMPTON Manufacturing CO
Current assignee: CRAMPTON Manufacturing CO
Priority date: 1949-02-26
Filing date: 1949-02-26
Publication date: 1953-05-19
Anticipated expiration: 1970-05-19

Description

May 19, 1953 'E. a. .mzosson $2,639,132

LATCH MECHANISM Filed Feb. 26, 1949 .2 Sheets-Sheet 1 n lawman. I Enwm 5. JAcoss'oN" Arroanzv May 19, 1953 E. a. JACOBSON LATCH MECHANISM 2;,Sheets-Sheet '2 Filed Feb. 26, 1949 .ll llll I \NveN'roR Bow: 5. JACOBSON 1a 9 Z g z ATTORNEY Patented May 19, 1953 UNITED STATES PATENT OFFICE LATCH MECHANISM Edwin B. Jacobson, Grand Rapids, Mich., as-

signor to Orampton Manufacturing Company, a corporation of Michigan Application February 26, 1949, Serial No. 78,576

9 Claims.

This invention provides a latch mechanism of the type designed to apply a closing force to a door. In addition to securing the door in closed position, a biasing action is applied thereto n order to force the door against the action of a sealing gasket tightly enough to prevent the passage of air. This type of device has come into general use in connection with the doors of refrigerators and other containers seeking to maintain a temperature differential between the interior and exterior thereof. It is the general practice to provide a refrigerator with a fixed member or keeper having an anchoring point for cooperation with a bolt positioned by a lock mechanism secured to the door. As the door is swung shut, the bolt engages the keeper with the required force to generate the necessary closing action.

The present invention provides for the mounting of the latch mechanism at or near the outer edge of a hollow sheet metal door in the general area where such a door is the strongest and most capable of sustaining the forces encountered during the locking action. The location of the lock mechanism in this general area tends to move the point of application of locking force to the greatest possible radius from the door hinge so that the net closing moment effective upon the door is maximized. With this arrangement, it is also possible to maintain the appearance and space-saving features of a concealed latch While, disposing the latch mechanism at a point where it is possible to run the sealing gasket inside the keeper, if desired. With the bolt and strike cooperating near the outer edge of the door, the strike and keeper can be attached directly to the Wall of the refrigerator without unduly thickening the same or providing heavy cantilever structure to transmit the locking forces to the wall panel. Further, the keeper which is used in connection with the present invention can be so proportioned that it has no large dimension extending outwardly from the surface on which it is mounted. In addition, the bolt positioning system of the present invention and the type of bolt which is used act to generate the required engaging action with a minimum of structure projecting from the door. This freedom from large coupling members removes a source of accident and injury and considerably increases the value of the mechanism.

The features of the present invention also provide a great many factors tending to reduce the cost of the installation of the completed position.

2 mechanism. A latch mechanism embodying the present invention may be designed and constructed so that it is entirely preassembled, including handle, escutcheon plate, and other equipment associated therewith. A hollow door fabricated of sheet material can be prov ded with a cut-out. through which the mechanism is inserted in acompletely assembled condition. Itcan then be fastened in position with the aid of fastening members passing through one of the panels of which the door is formed. V

The actuation of the handle of the latch mechanism embodying the present invention operates to move the bolt to the unlocked position, and suitable trigger means are provided to maintain the bolt in such position until the door is closed. The-preferred form of this trigger system involves the use of an element adapted to move in a path generally perpendicular to the door, such movement being caused by the collision of this element with a striker plate fastened to the refrigerator box. The action of this trigger element permits the strike plate to benothing'more than a flat surface of suitable hardness and wearing characteristics, and the tolerances on the lateral location of the same are of course no problem whatever.

' The preferred manner of applying the locking force under the present invention is for a spring to be so positioned that the entire locking action generated between the keeper and the engaging portion of the bolt is transmitted through the spring to a suitable support means associated with the mechanism housing. The spring thus provides a biasing effect which is not dissipated in friction between moving parts, and is generally independent of the accumulation or wear or manufacturing tolerances inevitable where a number of working parts are involved. If such biasing action were applied at a different point in the bolt-positioning system, these various factors would have to be considered before the action of the spring were finally brought to bear upon the keeper .togenerate the closing force.

A detailed analysis of the features of the present invention will be made by a discussion of the particular embodyments which are illustratedin the accompanying drawings. In these drawings,

Figure 1 illustrates a section through a mechanism taken on a horizontal plane, with the components of the mechanismin the locked Figure 2 is an exterior elevation of the com ponents of the lock mechanism shown in Figure 1.

Figure 3 is a section taken on a horizontal plane of the same mechanism shown in Figure 1, with the components in the unlocked position, and showing the door as it approaches the closed position.

Figure 4 is a perspective view showing the bolt utilized in the mechanism shown in Figures 1 and 3.

Figure 5 shows a perspective view of the crank shown in Figures 1 and 3.

Figure 6 shows a perspective of the trigger member utilized in the mechanism shown in Figures 1 and 3.

Figure 7 shows a section on a horizontal plane of a mechanism operating upon the same general principles as that shown in Figure l, but differing somewhat in detail design.

Referring to Figurel of thedrawings, the body portion of a refrigerator is generally indicated at l and the door at H. The latch mechanism indicated at E2 is provided with a handle 13 formed so that it can be conveniently grasped by the hand. Between the door H and the body [0, .the gasket 14 is placed in position shown to secure a seal preventing the passage of air into the box when the door is in locked position.

The keeper plate l'is attached directly to the wall of the refrigeratorby the fastenings i8, and providesan anchoring point ll adapted to cooperate with the bolt carried by the door of the refrigerator. The door I I is provided with a cutout 18 in the outer panel [9 through which the assembled latch mechanism [2 is inserted. inner panel $20 of the door H is also provided with a cut-out 2| through which the bolt and trigger mechanismof the latch project for cooperation with the keeper [5. The auxiliary cover plate 22 is provided with a recess to obtain the necessary clearance for the outer portion of the keeper [5. The latch mechanism 'is secured in the position shown by the fastenings 23 which pass through the innerpanel 20 and are received within suitable threaded holes 'in the housing 24 of the latch mechanism [2. To accommodate .small changes in the dimensions 'of the door II,

it is preferable to provide shims as noted-at 25 to assure the proper .fit between the escutcheon plate portion '28 of the housing 24 and the surface of the panel I9.

Referring to Figure 3,the bolt 27 is provided with the engaging portion comprising the roller 28 rotatably supported upon the positioning portion 29 of the bolt. The construction of the bolt '27 is best shown inlFigure 4, and it is ssentially a box-like structure of sheet metal having a hollow interior. At a point approximately midway between the ends of *the bolt, the slots 39 and 3| are provided for cooperation with the fulcrum pin 32. The spring 33 is interposed between the end of the bolt and the fulcrum pin 32, giving a net biasing action away from the pin and toward the pivotal connection-34 between the bolt 2'! and the crank 35. Crank 35 is rotatably supported upon the pivot '36 which also forms the pivot mounting for the handle l3. The spring 31 operates directly upon the handle to return the same to a fixed position regardless of the position of the latch mechanism.

An examination of the relative positions of the components in Figures 1 and 3 will indicate that the position of the pivotal connection 34 with respect to the line of centers 38 drawn between the pivot 36 and the pin 32 determines The i 4 whether the biasing action of the spring 33 will force the mechanism to open or closed position. As the handle 13 is actuated, the operating surface 39 develops pressure against the rear portion of the crank 35 and induces a clockwise rotation of the same about the pivot 35. Such rotation causesthe pivotalconnection. to move from the position shown in Figure :1 to that in Figure 3, and to cock the toggle system in the unlocked position. Due to the action of the stop 40, the mechanism is completely stable in this position and will remain so until one of the components of the toggle system are forceably ,move'd'in the opposite direction. This movement the outward movement of the bolt 27.

With the mechanism in the unlocked position, the return of the bolt to the locking position shown in Figure 1 is left to the control of the trigger element ll. This element is pivotally connected to the crank '35 at the point 42 and is slideably retained within the housing 24 so that it is free to more in response to force generated at the contact point 43 as the door of the refrigerator is swung shut. Just previous to the point where the door reaches the fully closed position, the contact point :23 collides with the strike surface 4 causing the trigger element M to move downwardly as seen in Figure 3. Such movement induces a counter-clockwise rotation of the crank 35, causing the pivotal connection 34 to move across 'the lineof centers 38. Shortly after the pivotal connection 34 passes this line of'centers, the mechanism becomes unstable under the action of the'biasing spring 33 and the toggle system snaps to the position shown in Figure 1 in which further rotation is limited by the engagement of the roller23 withthe anchoring point ll of the keeper 15. If the position of the anchoring point '11 is-not fanenough'away from the door to completely stop the action of the biasing spring .33, the bolt will be limited in its rotation by the surrounding structure of the latch mechanism. To develop the required locking force, however, it is preferable that the bolt shall be restrained in its movement by the :osition of the anchoring point l1. With the bolt in this position, the force of spring 33 is applied directly to the bolt and is transmitted through the engaging roller and the keeper plate to provide a net closing eifect upon the door H. The eiiect of the crank 35 is principally to determine the attitude of the bolt, although it may be noted that a component of force is generated at the pivotal connection 34 tending to reduce the eifectof the biasing spring 33 as creating a locking force. Due to the angle at which the forces are applied at the connection 34, the amount of this component is small and leaves the principal part of the force contributed by spring .33 to perform the locking action.

Referring to Figure 5, a view is shown of the construction of the crank 35. This member comprises the

side plates

45 and 45 in whichtheholes 41 and 41a (not shown) are'provided to act as bearings cooperating with the pivot 36. The

holes

48 and 49 are provided to act "as bearings cooperating with the pivot 42. "The edges 50 and form the surfaces cooperating withthe operating surface 39 of the crank I 3;

operates upon the same general principles as those described in connection withithe previous figures; but the location of the trigger, position of biasing spring, and other minor details are changed in some degree.- The biasing spring 53 is shown surrounding thepositioning portion of the bolt 54 which is supported (in generally the same manner as the bolt shown in Figures 1 and 3) upon the fulcrum pin- 55. In Figure '7, the trigger'element 56 is formed as a U-shaped memher having a slot in each side similar to the slot in'the positioning portion of the bolt 54. The fulcrum pin 55 engages both the slots in the trigger and the slot in the 'solid positioning portion 51 of the bolt in the same manner as shown in Figures 1 and 3. The trigger 56 is pivotally connected to the crank 58 at the point 59. The operating characteristics of the mechanism shown in Figure 7 are substantially identical to those described in connection with the previous Figures.

The particular embodiments of the present invention which have been shown in the accompanying drawing's'and have beendescrib'ed herein, are for illustrativepurposes only, and are not to be considered as limitations upon the scope of the appended claims. In these claims it is the intent of the inventor to claim the entire invention to the extent he is entitled in view of the prior art.

I claim:

1. A lock mechanism for cooperation with a keeper to secure a door in closed position, comprising: bolt means having an engaging portion, said engaging portion being adapted to engage and disengage said keeper through lateral move-1 ment, and a positioning portion; fulcrum means slideably supporting said bolt means on said positioning portion for rotation generating said lateral movement; crank means pivotally connected to said positioning portion at a point remote from said fulcrum; pivot means rotatably supporting said crank means for rotation on an axis parallel to the axis of rotation of said bolt, said pivotal connection being between said fulcrum means and said pivot means and adjacent to a line joining said fulcrum means and said pivot means; biasing means having a component of force urging said bolt toward said pivotal connection; releasing means inducing rotation of said bolt means about said fulcrum in a disengaging direction in response to the movement of a handle; trigger means cooperating with said crank and comprising a contact portion adapted to bear against a surface substantially parallel to said (1001 as said door is closed; support means for said trigger means permitting sliding movement of said contact portion in a direction substantially perpendicular to said door, said sliding movement generating rotation of said crank in a direction to move said bolt to engaging position .6 and carry said pivotal connection across the plane containing the axis of said fulcrum means and said pivotmeans. 5 7

2, A latch mechanism fora container door, said mechanism comprising: housing means adapted for attachment to said door; an elongated bolt having a keeper-engaging portion at one end, saidbolt being slideably and pivotally mounted at an intermediate point thereon in said housing means; crank means pivotally mounted in said housing means on an axis parallel to the axis'of the pivotal mountingof said bolt, said crank pivotally engaging said belt at the opposite end thereof from said keeper-engaging portion; biasing means urgingsaid bolttoward said crank; stop means limiting the movement of the point of pivotal engagement between said bolt and crank at points on opposite sides of the plane containing the axes of said pivotal mountings; handle means adapted to rotate said crank; and trigger means slideably mounted insaid housing for movement in a direction perpendicular to said door, said triggerv means at one end engaging said crank at a point remote from the pivotal mounting thereof, and the opposite end of said trigger means being disposed to contaet said container on the closing of said door, thereby urging said point of pivotal engagement of said bolt and crank across the planecontaining the axes of said pivotal mountings. I I 4 3. A latch mechanism for a door, said mechanism comprising? housing meansadapted for attachment to said door; an elongated hollow bolt having a keeper-engaging'portion at'one end, said bolt being slideably and pivotally mounted at an intermediate point thereon in said housing means at a pin secured to said housing means; crank means pivotally mounted in said housing means on an axis parallel to the axis of said pin, said axes being in a plane substantially perpendicular to said door, and said crank pivotally engaging said bolt at the opposite end thereof from said keeper-engaging portion; biasing means urging said bolt toward said crank, said biasing means including a compression spring disposed within said hollow bolt and acting between said bolt and said pin; stop means limiting the movement of the point of pivotal engagement between said bolt and crank at points on opposite sides of the plane containing the axes of said pivotal mountings; and handle means adapted to rotate said crank.

4, A latch mechanism for a door, said mechanism comprising: housing means adapted for attachment to said door; an elongated bolt having a keeper-engaging portion at one end, said bolt being slideably and pivotally mounted at an intermediate point thereon in said housing means; crank means pivotally mounted in said housing means on an axis parallel to the axis of the pivotal mounting of said bolt, said axes being in a plane substantially perpendicular to said door, and said crank pivotally engaging said bolt at the opposite end thereof from said keeperengaging portion; biasing means urging said bolt toward said crank; and handle means adapted to rotate said crank.

5. A latch mechanism, comprising: housing means; an elongated hollow bolt having a keeperengaging portion at one end, said bolt being slideably and pivotally mounted at an intermediate point thereon in said housing means at a pin secured to said housing means; crank means pivotally mounted in said housing means on an axis parallel to the axis of said pin, said crank .7 ,pivotally engagingsaid bolt-at the opposite end thereof from said-keeper-engaging portion; biasing means urging said bolt toward said crank,

said biasing means including a compression spring disposed-within said hollow bolt and acting between said boltand said pin; stop means-limiting the movement; of the point of pivotal engagement between said bolt and crank at points on opposite sides of the plane containing the axes of said pivotal mountings; and handle means adapted to rotate said crank.

6. A latch mechanism, comprising: housing means; an elongated hollow bolt having a keeperengaging portion at one end, said bolt being slideably and pivotally mounted at an intermediate point thereon in-said housing means at a pin secured to said housing means; crank means pivotally mounted in said housing means on an axis parallel to the axis of said pin, said crank pivotally engaging said bolt at the opposite end thereof from said keeper-engaging portion; biasing means urging said bolt toward said crank, said biasing means including a compression spring disposed Within said hollow bolt and acting between said bolt and a point fixed with respect to said housing means; stop means limiting the movement of the point of pivotal engagement between said bolt and crank at points on opposite sides of the plane containing the axes of said pivotal mountings; and handle means adapted to rotate said crank.

7. A latch mechanism, comprising: housing means; an elongated bolt having a keeperengaging portion at one end, said bolt being slideablyand pivotally mounted at an intermediate point thereon in said housing'means; crank means pivotally mounted in said housing means on an axis parallel to the axis of the pivotal 'mounting of said bolt; pin means pivotally connecting said bolt-at th'e oppositeend thereof from said keeper-engaging portion to said crank means; biasing means urging said bolt toward having a flange adjacent the inner panel, the

combination of the following: fixed housing means for securing the parts of said lock mechanisminoperatingrelationship, said cut-out being adapted to-receive said mechanism and housing means; and mounting means securing said mechanism andhousingmeans in said door including fastening means passing through said flange and engaging said housing means. I

9. Incombination with a latch mechanism for securing a-hollow door in closed relationship with a container,-said door comprising oppositely disposed panels in spaced relationship and having a cut-out in an outside panel adjacent the outer edge thereof, the combination of the following: fixed housing means for securing the parts of *said lock mechanism in operating relationship,

said cut-out-being adapted to receive said mechanism and housing means; and mounting means securing said mechanism and housing means in said door including fastening means passing through the inner panel of said door and engaging said housing means.

EDWIN B. JACOBSON.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,744,424 Trudeau Jan. 21, 1930 883,804 Marque Oct. 18, 1932 2,195,542 Shafier et a1 Apr. 2, 1940 2,445,709 'Curtiss, Jr July 20, 1948 2,451,380 Curtiss, Jr Oct. 12, 1948