US2679427A - Latch mechanism - Google Patents

Description

May 1954 R. E. JOHNSON 2,679,427

LATCH MECHANISM Filed Feb. 18, 1952 2 Sheets-Sheet l /24 40\ ig' as IMI/7" IN V EN TOR.

wan/J y 1954 R. E. JOHNSCIJN 2,679,427

LATCH MECHANISM Filed Feb. 18, 1952 2 Sheets-Sheet 2 INZENTOR.

Patented May 25, 1954 UNITED ST TENT OFFICE LATCH MECHANISM Robert E. Johnson, Marne, Mich., assignor to Jervis Corporation, Grandville, Mich., a corporation of Michigan Application February 18, 1952, Serial No. 272,186

4 Claims.

does not close the door with sufiicient force to compress the gasket. It is also desirable, when the latch is released to permit opening of the door, that the latch bolt be toggled or cocked in an open position, from which position it may readily be tripped by a relatively light, properly directed force. This enables the door to be closed with a minimum force.

With such a latch mechanism it is not an uncommon occurrence that the latch bolt is inadvertently tripped from its cocked position while the door is open. Accordingly, it is desirable also that the latch bolt be movable from its keeper engaging position to a keeper by-passing position merely by slamming the door shut. Where this feature is not present, if the latch mechanism becomes uncooked while the door is open it is necessary to operate the latch handle before the door can again be closed.

It is another object of the invention to provide an improved cocking latch mechanism.

It is another object of the invention to provide an improved cocking latch mechanism for mountin on a door and cabinet, for example, which latch mechanism permits the door to be slammed shut even though the latch mechanism may have been tripped from its cocked, position while the door was open.

It is another object of the invention to provide an improved latch mechanism having the features described above and in which the various movements necessary to eifect these features are accompanied by a minimum of friction.

It is another object of the invention to provide an improved latch mechanism havin the various features described above while being simple, reliable and economical to manufacture.

This invention, together with further objects and advantages thereof, will best be understood by reference to the following description taken in connection with the accompanying drawings, and its scope will be pointed out in the appended claims.

In the drawings, in which like parts are desig nated by like reference numerals,

, Fig. 1 is a cross-sectional plan view of a latch mechanism illustratin one embodiment of the invention, the mechanism being shown in connection with a refrigerator door and cabinet;

Fig. 2 is an elevational view of the same latch mechanism, the refrigerator door and cabinet being omitted in the interest of clarity;

Fig. 3 is a cross-sectional View taken along the line 3-3 of Fig. 2 but omitting the refrigerator door and cabinet;

Fig. 4 is a cross-sectional view taken along the line 4-5 of Fig. 2 but showing the latch mechanism in a diiferent operating position; and

Figs. 5 and 6 are views similar to Fig. 4 but showing the latch mechanism in different operating positions.

The latch mechanism disclosed in the drawings is particularly adapted for application to the edge of an otherwise complete door, in which case certain portions of the housing of the latch mechanism are preferably of chrome platedmetal and attractive in contour. It is to be understood, however, that the invention is not limited to such an application but may be employed in a latch mechanism mounted within a door, as is more common in the case of refrigerators.

A supporting frame It is provided having an outer wall I i and an inner wall I 2. It will be noted by reference to Figs. 1 and 3 that a third wall 4 la is also provided which lies alongside the outer wall I l and extends around the right-hand end of the structure and doubles back'to complete the closure. The wall Ila is exposed to view in the illustrated embodiment of the invention, and serves no function other than to provide an ornamental exterior surface. It may be secured to the frame in by any suitable means, not illustrated in the drawing.

The inner wall i2 has portions thereof formed to fit the edge of a refrigerator door since the latch mechanism illustrated in the drawings is intended to be secured to the edge of a door l3. Certain portions of the inner wall It, however, extend outwardly of the refrigerator door to form brackets for supporting various operating parts of the latch mechanism.

The latch mechanism includes a latch bolt l4 preferably channel shaped in cross section over a part of its length in the interest of rigidity and strength. The opposed walls of the latch bolt have matching slots l5 intermediate their ends and extending substantially longitudinally of the latch bolt. A pivot pin is extends through these slots and is secured to the inner and outer walls H and 12 of the supporting frame Hi. This structure permits both a slidin movement and a pivotal movement of the latch bolt with respect to the supporting frame.

At the left-hand end of the latch bolt is a keeper engaging roller I! mounted on a pin l8 which extends through and is secured to both walls of the bolt member. The roller I1 is adapted to engage a keeper l9 which is secured to the side of a cabinet with which the door [3 cooperates.

At the right-hand end of the latch bolt 14 there is another roller 22 rotatably secured to the latch bolt by a pin 23. The roller 22'is'adapted to engage and roll along one surface of a fixed member 24 which forms a part of the supporting frame It. The member 24 maybe struck from the inner wall l2 of the supporting frame but in the illustrated embodiment constitutes a separate plate which is secured at its opposite ends to the supporting. frame walls H and i2;

A bolt actuator 25 is pivotally mounted on the supporting frame Why a pivot pin 26; In the illustrated embodiment the bolt actuator is in the form of a bell crank, the lower end of which is pivotally secured to one end of a spring bar 21 through a pin 28. The other end of thespring bar 21 is engaged in a slot 29 formed in a bracket 30 which is struck from the lower wall 3| of the supporting frame H). A compression spring 32 is wound around the body of the spring bar and is compressed between the bracket 30 and a shoulder 21a near the right-hand end of the spring bar 21.

Thespring 32 being in compression, urges the lower end of the actuator 25 to the right and tends to rotate the entire actuator around the pivot pin 28' in a counterclockwise direction as viewed in Figs 2-6.

A cam roller 33 is rotatably mounted at the left-hand or free end of: the actuator 25 by a pin 34. This cam roller cooperates with a cam pin secured to the latch bolt near its righthand end. The cam pin 35 disclosed in the drawings is also disclosed and is claimed in application Serial No. 58,953, entitled Refrigerator Latch, filed November 8,1948, by Lloyd L. Anderson, and assigned to the same assignee as the present invention.

The actuator 25, like the latch bolt i4, is preferably channel shaped in. cross section over at least a portion of its length, and the opposed wallsv thereof are so spaced that they may lie immediately outwardly of the two walls of the latchbolt, all as best seen in Fig. 3. The pin 34 on which the cam roller 33 ismounted is secured to both walls of the actuator 25 and slots [to are provided in the walls of the latch bolt M for freely receiving the pin,- 34 in order that the cam roller 33 may enter the space between the walls of the latch bolt to the position illustrated in Fig. 6.

With the latch mechanism in the position illustrated in Fig. 6,. the cam roller 33, being pressed downwardly under the influence of the spring 32, exerts a force against the cam pin 33 tending to drive the latch bolt l4 toward the right, the force being greatly magnified through the mechanical advantage provided by the arrangement of the cam roller 33 and the cam pin 35. Also, the pin 34, on which the cam roller 33 is mounted, may engage the bottom of the slots Ma and thereby urge the latch bolt M to rotate in a clockwise or door locking direction. The roller 22 is thereby maintained forcefully against the plate 24.

This is the keeper engaging position of the latch bolt, the roller I! being maintained upwardly, as viewed in Fig. 6, in the recess of the keeper l9, and being urged to the right (by pressure of 33 against pin 35 which latter is mounted on latch bolt I4) whereby the supporting frame of the latch mechanism, and hence the door l3, are urged forcefully to the left with respect to, the keeper 19. This arrangement is particularly desirable in a refrigerator application since this force may be employed to compress a gasket 38 between the facing surfaces of the door l3 and the cabinet 20.

A handle 40 is provided for controlling the latch mechanism, and more particularly for moving the latch mechanism to a cocked or open position. The handle 49 is pivotally mounted on the same; pin 26,. about which the actuator 25 rotates, and the lower end of the handle 40 engages the actuator at a, point M. It will be apparent that when the handle 40 is moved in a clockwisedirection the actuator 25. will also move ina clockwise direction, compressing the spring 32. A spring 42 is wound around the pivot pin 26, one-end engaging a bracket 12a struck from the inner wall l2 of the supporting. frame and the other end of the spring engaging the lower end of the handle 40. The spring 42 thus urges the handle 40' in a counterclockwise direction and exerts a sufficient force to move the handle hack to the position illustrated in Fig. 6 when it has-been released.

The clockwise movement. of the actuator 25 caused by. operation of the handle 40 withdraws the cam. roller 33 from its position to the left of the cam pin 35,,illustrated in Fig. 6, to the positiondllustrated in Fig. 5.. The opening force applied by an operator to the-handle 40 also tends todraw the. refrigerator door to the right, away from the cabinet 23. The latch bolt roller l1, however, remains temporarily engaged with the keeper l9. and hence the latch bolt 14 is drawn to the left withrespect to the remainder of the latch. mechanism such that it assumes the position illustrated in Fig. 5..

The latch bolt M' is alsourged toward the position'. illustrated in Fig. 5 by a relatively light springzM wound around the pin 5. One'end of the spring M engages a bracket (2?), which is struck from the inner wall i2 of the supporting frame 10;, and the other end ofthis spring engagesthe latch bolt l4 as shown. The force exerted by the relatively light spring 44 helps to insure. movement of the latch bolt M from the position illustrated in Fig. 6 to the position illustrated in Fig. 5- when the handle 40 is op erated.

In the position illustrated in Fig. 5 the cam pin 35 lies under the cam roller 33, the latter engaging. a flattened surface 35a at one side of the cam' pin 35. Since the point of contact between thecam roler 33 and the cam pin 35 issubstan- .tially in alignment with the pivotal axes of the roller 22 and the cam roller 33, and since the surface of the member 24 which the roller 22 contactsextends substantially at right angles to a line drawn between these pivotal axes, thelatch bolt tends to remain in the position illustrated in Fig; 5., This is the cooked or open position of the latch mechanism, the bolt roller I! being moved downwardly, in Fig. 5, to a position in which it may clear the nose-of the keeper. The bolt member l4 tends to remain in this position as long as no external forces are applied thereto.

The downward movement of the bolt roller H as the bolt slides to the left results from the Y vention, since the plate fact that the slots l deviate by a substantial angle from the direction of opening and closing movement of the door when the latter is adjacent its closed position. Accordingly, as the latch bolt slides from right to left as in moving from the position of Fig. 6 to the position of Fig. 5, the bolt roller is moved downwardly such that it may clear the keeper l9. In the illustrated embodiment of the invention the slots l 5 also deviate by a substantial angle from the surface of the plate 2A which the roller 22 contacts, with the result that as the latch bolt slides between the positions illustrated in Figs. 5 and 6, it also pivots through a small angle about the axis of the roller 22. This increases the vertical movement of the latch bolt roller I? corresponding to a given length of sliding movement of the latch bolt.

The combined sliding and pivotal movement of the latch bolt between the positions illustrated in Figs. 5 and 6 is an optional feature of the in- 2d might readily be made to extend parallel to the slots whereby a pure sliding movement would be employed for the latch bolt as it moves between the positions illustrated in Figs. 5 and 6. Such a latch bolt would be workable and would still incorporate various features of the invention although it is not the preferred embodiment of the invention.

With the latch bolt in the position illustrated in Fig. 5, it will be apparent that a relatively small force applied to the latch bolt, tending to drive it to the right, will move the cam pin to a position in which the cam roller 33 will forcefully urge the cam pin further to the right, wher upon the latch bolt will be moved into the position illustrated in Fig. 6. Such a tripping force is obtained when the door is moved toward its closed position by virtue of the fact that the latch bolt I4, and more specifically the latch bolt roller [1, strikes a tripping surface lSa on the keeper 19. Accordingly, the latch bolt is readily tripped from its cocked position illustrated in Fig. 5 merely by movement of the door toward its closed position. After the latch mechanism has been tripped the spring 32, acting through the cam elements 33 -;1."

and 35, urges the latch bolt l4 to the right with respect to the main body of the latch mechanism, thereby drawing the door shut and compressing the gasket 38.

As previously indicated, if the latch bolt should be tripped from its cocked position while the door is open, it is desirable that the latch mechanism be so arranged that the door maybe slammed shut. This means that the latch bolt must be movable from its keeper engaging position to a keeper by-passing position as a result of the force exerted thereagainst by the keeper.

When the latch mechanism is in the keeper engaging position illustrated in Fig. 6, it will be apparent that the latch bolt !4 cannot be slid to the left to its cocked position since the cam roller 33 is substantially in direct alignment with the cam pin 35. Movement of the latch bolt M to cocked position must be at least initiated by upward movement of the cam roller 33. Furthermore, when the latch bolt roller ll strikes the keeper it, with the latch bolt in its keeper engaging position and the door being manually moved toward its closed position, the force can erted by the keeper against the latch bolt roller is not properly directed to move the latch bolt toward its cocked position. Accordingly, another movement of the latch bolt must be provided for if the door is to be movable to without recocking the latch mechanism.

its closed position In the illustrated embodiment of the invention the latch bolt I4 is pivotable about the pin Hi from the position illustrated in Fig. 6 to the position illustrated in Fig. 4. This pivotal movement carries the roller 22 away from the plate 24, while the cam roller 33 remains substantially fixed with respect to the cam pin 35. The actuator 25 is thereby pivoted about the pin 26 in a clockwise direction and the spring 32 is compressed. This movement is therefore resisted by the spring 32 but the force required to slam the door shut may be relatively light depending upon the slope of the keeper l9.

It will be apparent that when the latch bolt roller ll has passed over the nose of the keeper, it will enter the keeper slot forcibly under the influence of the spring 32 and the actuator 25.

It has been found that the sliding movement of the latch bolt M from its keeper engaging position to its cocked or open position results in a smooth operation and utilizes the operators pull on the handle to good advantage to move the latch bolt to its cocked position. More specifi cally, when the operator pulls on the handle 40, thereby pivoting the actuator 25 in the clockwise direction, the same pull urges the door 13 toward its open position. As long as the latch bolt roller i1 is still engaged by the keeper l9 this outward pull by the operator urges the latch bolt M to the left with respect to the other portions of the latch mechanism, and more particularly with respect to the cam roller 33. Also when the latch bolt is tripped from its cocked position by striking of the latch bolt roller i3 against the tripping face iiict of the keeper it, the force applied to the latch bolt by the keeper is substantially in alignment with the direction of movement of the latch bolt as it moves from its cocked position to its keeper engaging position. Accordingly, the tripping force is eiiiciently applied to trip the latch bolt.

The roller 22 engaging a single track, namely plate 24, minimizes friction in the movement of the latch bolt between its keeper engaging position and its cocked position.

Still further the pivotal movement of the latch bolt from its keeper engaging position to its keeper by-passing position permits efficient application of the force required to efiect such move ment. More specifically, the force applied by the face of the keeper 5 9 against the latch bolt roller ll may be substantially tangent to the path of the latch bolt roller as it pivots about the pin it fromits keeper engaging position to its by-passing position. Accordingly, the door may be slammed shut, when the latch bolt has inadvertently been tripped while the door is open, with a minimum of force in view of the strength of the spring 32 provided for compressing the gasket 33 and maintaining the door in its closed position.

Incorporation of these features results in a latch mechanism having the basic characteristics of being cockable and of permitting slamming of the door when the latch mechanism has inadvertently been tripped, while being easily operable because of the minimizing of friction and the efficient transformation of operating forces. Such a latch mechanism is also simple in construction and is inherently dependable in operation.

g It will be apparent that the invention may be varied in its physical embodiment without departing from the spirit of the invention, and it is desired, therefore, that the invention be limited only by the scope of the appended claims.

amon

The invention having thus been described, what is claimed and desired to be secured: by Let ters Patent is:

1. A latch mechanism for mounting on a door, movable between open and closed positions with respect to a cabinet and for cooperating with a keeper mounted on such cabinet, said latch mechanism including an elongated bolt member extending generally in the direction of movement of said door, keeper engaging means associated with one end of said bolt member, roller and track means associated with the other end of said bolt member for guiding said other end of said bolt member in linear movement thereof in the general direction of movement of said door, pin and slot means associated with said bolt member intermediate its ends for permitting unrestricted pivotal movement and limited linear movement of said bolt member, the slot of said pin and slot means extending in a direction forming a substantial angle to the direction of movement of said door whereby linear movement of said other end of said bolt member toward said one end thereof causes saidbolt member to pivot about said other end from a keeper engaging position to a disengaged position, an actuator member, a cam element mounted on said actuator, a cam element mounted on said bolt member adjacent sa-id other end thereof, and spring means operating on said actuator to urge said actuator cam element toward said bolt member in a direction substantially perpendicular to said bolt member, said actuator cam element engaging and lying in the path of said bolt member cam element when said engaging position, said bolt member cam element engaging and lying in the path of said actuator cam element when said bolt member is in said disengaged position, said roller and track means restraining said other end of said bolt member against lateral movement by the force of said spring operated actuator acting through said'ca-m elements when said bolt member is in said disengaged position.

2. A latch mechanism for mounting on a door, movable between open and closed positions with respect to a cabinet, and for cooperating with a keeper mounted on such cabinet, said latch mechanism including an elongated bolt member I extending generally in the direction of movement of said door, keeper engaging means associated with one end of said bolt member, roller and track means associated with the other end of said bolt member for guiding said other end of said bolt member in linear movement thereof in the general direction of movement of said door, pin and slot means associated with said bolt member intermediate its ends for permitting unrestricted pivotal movement and limited linear movement of said bolt member, the slot of said pin and slot means extending in a direction forming a substantial angle to the direction of movement of said door whereby linear movement of said other end of said bolt member toward said one end thereof causes said bolt member to pivot about said other end from a keeper engaging position to a disengaged position, an actuator member, a cam element mounted on said actuator, a cam element mounted on said bolt member adjacent said other end thereof, and spring means operating on said actuator to urge said actuator cam element toward said bolt member in a direction substantially perpendicular to said bolt member, said actuator cam element engaging and lying in the path of said bolt membolt member is in said keeper ber cam element when said bolt member is in said keeper engagin position, said bolt member cam element engaging and lying in the path of said actuator cam element when said bolt member is in said disengaged position, said roller and track means restraining said other end of said bolt member against lateral movement by the force of said spring operated actuator acting through said cam elements when said bolt member is in said disengaged position, one of said cam elements comprising a cam roller, the other of said cam elements having a flattened surface extending substantially in the direction of movement of said door and being engaged by the said cam roller when said bolt member is in said disengaged position.

3. A latch mechanism for mounting on a door, movable between open and closed positions with respect to a cabinet, and for cooperating with a keeper mounted on such cabinet, said latch mechanism including an elongated bolt member extending generally in the direction of movement of said door, keeper engaging means associated with one end of said bolt member, roller and track means associated with the other end ofsaid bolt member for guiding said other end of said bolt member in linear movement thereof in the general direction of movement of said door, pin and slot means associated with said bolt member intermediate its ends for permitting unrestricted pivotal movement and limited linear movement of said bolt member, the slot of said pin and slot means extending in a direction forming a substantial angle to the direction of movement of said door whereby linear movement of said other end of said bolt member toward said one end thereof causes said bolt member to pivot about said other end from a keeper engaging position to a disengaged position, an actuator member, a cam element mounted on said actuator, a cam element mounted on said bolt member adjacent said other end thereof, and spring means operating on said actuator tourge said actuator cam element toward said bolt member in a direction substantially perpendicular to said bolt member, said actuator cam element engaging and lying in the path of said bolt member cam element when said bolt member is in said keeper engaging position, said bolt member cam element engaging and lying in the path of said actuator camelement when said bolt member is insaid disengaged position, said roller and track means restraining said other end of said bolt member against lateral movement by the force of said spring operated actuator acting through said. cam elements when said bolt member is in said disengaged position, one of said cam elements comprising a cam roller, the other of said cam elements being a pin having a flattened surface extending substantially in the direction of movement of said door and being engaged by the said cam roller when said bolt member is in said disengaged position.

4'. A latch mechanism for mounting on a door, movable between open and closed positions with respect to a cabinet and for cooperating with a keeper mounted on such cabinet, said latch mechanism including an elongated bolt member extending generally in the direction of movement of said door, keeper engaging means associated with one end of said bolt member, roller and track means associated with the other end oi said bolt member for guiding said other end 01 said bolt member in linear movement thereoi in the general direction of movement of salt ber to pivot about said other end from akeeper 0 engaging position to a disengaged position, an actuator member, a cam element mounted on said actuator, a cam element mounted on said bolt member adjacent said other end thereof, and spring means operating on said actuator to urge said actuator cam element toward said bolt member in a direction substantially perpendicular to said bolt member, said actuator cam element engaging and lying in the path of said bolt member cam element when said bolt member is 20 in said keeper engaging position, said bolt member cam element engaging and lying in the path of said actuator cam element when said bolt member is in said disengaged position, said roller and track means restraining said other end of said bolt member against lateral movement by the force of said spring operated actuator acting through said cam elements when said bolt member is in said disengaged position, said actuator member comprising a bell crank pivotally mounted near its center, said actuator cam element being mounted on one arm of said bell crank, and said spring means extending alongside said bolt member and operating against the other arm of said bell crank.

References Cited in the file of this patent UNITED STATES PATENTS

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