US2679425A - Latch - Google Patents

Description

May 25, 1954 R. E. JOHNSON LATCH 3 Sheets-Sheet 1 Original Filed March 23 1950 INVENTORS Rosem- E. OHNSON BY y 044/ A'rwoanu's LATCH May 25, 1954 Original Filed March 23 1950 3 Sheets-Sheet 2 '\=\a-. 3. 18 luveu'roas A'rroausvs l) 5 R. E. JOHNSON 2,679,425

LATCH Original Filed Match 23 1950 3 Sheets-Sheet 3 luveu'roa Rdsem' E.JoHNsoN 3 a xwm Patented May 25, 1954 LATCH Robert E. Johnson, Marne, Mich, assignor to Jervis Corporation, Grand-ville, Mich, a corporation of Michigan Continuation of abandoned application Serial No.

0. This application Feb- ISIAG-I, March 23',

ruary- 6, 1952, SerialN 9 Claims.

This application is a continuation of application Serial No. 151,461, entitled Latch, and filed March 23, 1950, by Lloyd L. Anderson and Robert E. Johnson, said application having subsequently been changed to a sole application of Robert E. Johnson and later abandoned.

This invention relates to latches and: it is an object of the invention to provide an improved latch structure.

A latch constructed in accordance with the invention is simple, economical and practical. It has been developed primarily for use in conjunction with refrigerators but is not limited to such application. Preferably the latch is mount e'd adjacent the free vertical edge of a hingedly mounted refrigerator door which is used to close the entrance opening of a refrigerator casing. In practice such a latch is normally concealed between the inner and outer sides of the door and only the operating handle, which is used to release the latch to open the door, appears on the outer side of the door.

It is another object of the invention to provide a simple, and inexpensive latch mechanism which is suitable for use with the relatively heavy refrigerator doors now in use and which is effective in compressing a sealing gasket between a refrigerator door and casing with sufficient force to insure a proper seal.

It is another object of the invention to provide an improved latch which may be released with a minimum of force on the operating handle.

It is another object of the invention to provide an improved latch mechanism having the characteristics referred to above while at the same time being simpler and more durable than latch structures heretofore known.

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 designated by like reference numerals,

Fig. 1 is a horizontal section through a fragmentary portion of a refrigerator door and the adjacent refrigerator casing, with the latch of the invention shown in plan;

Fig. 2 is a horizontal section through the latch substantially on the plane of line 2-2 of Fig. 3, showing the latch in its cocked position;

Fig. 3 is a vertical section substantially on the plane of broken line 3-3 of Fig.

Fig. 4 is a horizontal section throughtbe' latch 2 substantially on' the plane of line 4-4 of Fig. 3 and showing the latch in a keeper by-passing position; and

Fig. 5 is a horizontal section like Fig. 2 but showing the" position of the latch parts when the door is completely closed, and the latch is engaged with its keeper.

In the drawings a latch mechanism illustrating one embodiment of the invention is shown applied to a refrigerator, but it is to be understood that the invention is not limited tosuch an application. A portion of a refrigerator casing l is shown in Fig. l, a latch keeper or strike 2 being secured thereto. Preferably, the keeper is adjustable in its position with respect to the casing l in order that it may readily be positioned for proper cooperation with the latch mechanism. A portion of a refrigerator door 3 may also be seen in Fig. 1, the door preferably being hinged at one side, opposite the side portion shown, and serving to close the entrance opening of the refrigerator casing.

A resiliently compressible sealing gasket 4' is preferably employed to provide a substantially airtight seal between the door 3 and the casing l. Customarily the gasket 4 is mounted on the door as illustrated in Fig. 1 and is arranged to cooperate with a substantially planar surface of the refrigerator casing I. A plate 5 is secured to the inner wall of the door 3 and is shaped as illustrated in Fig. 1 to form a recess within the door 3 for receiving thekeeper 2. The plate 5 is slotted in its right-hand portion to permit access thereto of one end of a latch bolt for cooperation with the keeper 2.

At the outer side of the door a handle 8 is arranged for operating the latch mechanism, the handle 6 being pivotally mounted on any suitable support which is preferably covered by a housing 1. A push rod or pin 8 is arranged to be forced inwardly by the handle 6 when the latter is manually pivoted outwardly to release the latch. A base member including portions 9, It and H is secured to the door 3 in the position shown in Fig. 1 by any suitable fasteningmeans, and is arranged to support the latch mechanism which constitutes the present invention.

The latch mechanism itself includes a frame work comprising two substantially parallel sides l2 connected by a cross member l3, the latter being turned outwardly to form an ear It which may be secured to the base member portion H. The two side pieces l2 are turned outwardly of each other to form ears l5 which may be secured to the frame member portions ID as shown.-

Two pins or rods I6 and H are secured to the opposite side pieces l2 and extend therebetween, these pins serving to pivotally support certain operating parts of the latch mechanism. On the pin IS an actuating member is pivotally mounted, this actuating member or actuator having spaced sides l8 integrally connected by cross members It and 20. The cross member I9 is so positioned that it may be engaged by the rod 8 to turn the actuator in a clockwise direction about its pivot pin |6 when the handle 6 is pivoted outwardly. A cam element is arranged on the actuator comprising a shaft 22 secured to and extending between the sides It of the actuator, and a cam roller 2| rotatably mounted on the shaft 22. A relatively heavy torsion spring 23 is arranged around the pivot pin l5, one end of the spring bearing against the cross member 28 of the actuator and the other engaging one end of a slot in the cross member |3 of the latch frame. The spring 23 urges the actuator in a counterclockwise direction at all times.

A latch bolt is provided having two spaced walls 24 connected by a cross member 25 best seen in Figs. 2 and 5, the cross member being extended to form a trip foot 26, the operation of which is subsequently described.

The actuator is arranged between the spaced sides |2 of the latch frame, and the latch bolt is arranged between the sides N3 of the actuating member, all as best seen in Fig. 3. The latch frame, the actuator, and the latch bolt are all substantially boxlike in form, this resulting in the very strong and rigid construction.

The actuator is slotted at 2'! and at 28 through both walls 24 thereof, the pin extending through the slots 21 and the shaft 22 of the cam roller 2| extending through the slots 28. The latch bolt also includes arms 29 which form extensions of the sides 24, and between the free ends of the arms 29 there extends a pin or shaft 3| rotatably supporting a latch bolt roller 30. A relatively light torsion spring 32 is arranged around the pin one end of the spring engaging the cross member l3 of the latch frame and the other end bearing against-a lug 33 bent laterally from one side wall 24' of the latch bolt. It may readily be seen by reference to the drawings that the spring 32 urges the latch bolt to pivot in a clockwise direction about the pin I1 and urges the latch bolt in such a direction as to retain the pin H at the right-hand ends of the slots 21.

A cam pin 34 having flattened sides 35 is secured to and extends between the sides 24 of the latch bolt, the ends of this pin extending outwardly beyond the walls 24 of the latch bolt whereby they are in position to engage the edges of the walls 18 of the actuator, all as best seen in Fig. 3. The cam pin 34 with at least one flattened surface is disclosed and 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 application.

The latch bolt is pivotable about the pin between a keeper engaging position illustrated in Figs. 1 and and a cooked or open position illustrated in Fig. 2. When the latch bolt is in either of these positions the pin I1 is located at the right-hand ends of the slots 21.

In the keeper engaging position of the latch bolt, the bolt roller 30 contacts the inner edge or surface of the keeper as shown in Figs. 1 and 5. Under these conditions the actuator is in its counterclockwise position such that the cam roller mechanism is cocked, that is,

2| is arranged above the cam pin 34 as seen in Fig. 5. The downward force exerted by the cam roller 2| on the cam pin 34 urges the latch bolt toward its keeper engaging position. This downward force may readily be seen to be directed along a line disposed at nearly degrees to the path of the cam roller 2 Accordingly a wedging action is obtained which results in the force applied to the cam pin 34 being much greater than the force urging the cam roller 2| to the left in Fig. 5. The large, door-closing force thereby obtained serves to compress the gasket 4 and to hold the door firmly closed.

When the door is to be opened the handle 6 is manually pivoted away from the door 3 whereupon the rod 8 is forced inwardly against the cross member IQ of the actuator. This force pivots the actuator in a clockwise direction and moves the shaft 22, on which the cam roller 2| is mounted, to the right-hand ends of the slots 28 in the latch bolt. The latch bolt is thereby moved in a clockwise direction to its open or cocked position illustrated in Fig. 2 wherein the cam roller 2| engages the right-hand flattened surface 35 of the cam pin 34.

This clockwise rotation of the latch bolt is caused or may be caused by any one of three forces, all of which may act in concert. The manual force applied to the handle 6, necessary to pivot the handle outwardly, also serves to draw the door in an opening direction. This in turn applies a clockwise torque to the latch bolt. The relatively light spring 32 also urges the latch bolt in a clockwise direction. These two forces acting alone or in concert serve to move the latch bolt in a clockwise direction as rapidly as the removal of the cam roller 2| from the path of the cam pin 34 will permit. Also the shape of the slots 28 in the side walls 24 of the latch bolt requires that the latch bolt move to its cocked or open position as the actuator is rotated in a clockwise direction.

When the cam roller 2| engages the right-hand flattened surface 35 of the cam pin 34, the latch the torque of the spring 23 is ineffective to pivot the actuator and the latch bolt in counterclockwise directions. It will be readily recognized by those skilled in the art that the force applied by the cam roller 2| to the cam pin 34 is normal to the flattened surface 35 when the cam roller engages that flattened surface. The direction of this force will then be along a line passing through the axis of the shaft 22 and the point of contact between the cam roller 2| and the cam pin 34. It will be noted by reference to Fig. 2 that this line when extended to the right passes slightly below the axis of the pin IT and hence slightly below the axis of rotation of the latch bolt. This force then tends to rotate the latch bolt further in a clockwise direction, such further rotation of the latch bolt being limited by the fact that the shaft 22 engages the right-hand ends of the slots 28. The latch bolt and the actuator will therefore remain in this cocked position until disturbed by outside forces.

When the door is moved toward its closed position the trip foot 26, previously mentioned, will strike against the outer end of the keeper 2 whereby the momentum of the door, or a closing force applied thereto, causes the latch bolt to swing in a counterclockwise direction about the pin When this counterclockwise movement of the latch bolt has progressed to the point that the cam roller 2| passes onto the upper arcuate surapplied by the cam roller to the cam pin swings about such that it extends above the axis of the pin il. Under thes circumstance the cam roller 2| urges the latch bolt in a counterclockwise direction with an ever increasing force. As previousiy pointed out when the latch mechanism reaches the posi ion illustrated in Figs. 1 and 5 a wedging action obtained whereby the latch bolt is urged in a counterclockwise direction with a torque greatly exceeding the torque applied to the actuator, whereby the door is held firmly closed and the gasket 4 is forcefully compressed to seal the refrigerator entrance.

It occasionally happens that when the refrigerator door is open the latch mechanism is jarred or a force is otherwise applied thereto which causes the latch mechanism to trip. lhe latch mechanism would then be in the condition illustrated in Figs. 1 and 5 but would not be in engagement with the keeper 2. When this occurs and the door is moved toward its closed position the latch bolt roll-er 3c engages the inclined outer edge of the keeper. If the door is closed with sufficient force the latch bolt will be forced to slide to the right. Under these conditions the pin 5? is moved relatively toward the left-hand ends of the slots 2? in the latch bolt and the actuator is caused to pivot in a clockwise direction against the action of the spring 23' by virtue of the engagement of the shaft 22 with the lefthand ends of the slots 2%.

When the latch bolt roller 38 is about to pass over the nose of the keeper as illustrated in Fig. 4, the pin ll substantially at the left-hand ends of the slots 21'. Further closing movement of the door permits the latch bolt roller 36 to roll along the inner surface of the keeper 2 primarily under the influence of the spring 23 acting through the actuator and partially under the influence of the spring 32.

The latch mechanism disclosed and described herein has various desirable features of latch mechanisms heretofore known. For example, it produces a large closing force at the final stage of the closing movement of the door whereby it may hold the door firmly closed and compress a sealing gasket. Also it cooks in its open or re leased position whereby relatively small closing force is normally required. Still further the latch mechanism permits slamming of the door to its closed position even though the latch mechanism may have become uncooked while the door is open. At the same time the latch mechanism disclosed and described represents a substantial simplification of latch mechanisms heretofore known which have the above described operating features. This latch mechanism is substantially a two-part mechanism comprising an actuator and a latch bolt whereas previously known latch mechanisms, such as that described in Serial No. 58,953 referred to above, employ three principal parts, namely, a latch bolt, an actuator, and a spring bar or spring guide. In addition to this simplification of the latch mechanism construction, a latch mechanism constructed in accordance with the invention is inherently rugged and easy to operate. Furthermore, in the illustrated and described modification of the invention stops for limiting the rotation of both the latch bolt and the actuator in both the clockwise and counterclockwise directions are all incorporated in the simple structure comprising the slot Ed and the cam roller shaft 22.

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 lim ited only by the scope of the appended claims.

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

1. A latch structure comprising, a'support having spaced apart parallel sides integrally connected together at one edge of each of said sides, an actuating member pivotally mounted on and located between the sides of the support, adjacent one end of the actuating member and at the outer portion of the support, said actuating member extending inwardly, said actuating member having parallel sides connected by integral cross members, one of which provides a ledge for turning the actuating member about its pivot, relatively heavy spring means for turning said actuating member in one direction, a roller mounted between the sides of and carried by said actuating member at the inner end thereof, a floating latch bolt comprising two parallel spaced sides integrally connected at one of the edges thereof by a cross member between them, the sides of said bolt each having a slot therein of a generally arcuate form and said roller havin an axle extending through said slots, the roller being 10- cated between the sides of the bolt, said sides of the bolt each having a second slot therein spaced from the first slots, a strike engaging member comprising a roller mounted on and located between the sides of said bolt at the inner end thereof, a rigid pin extending between and secured to the sides of the support passing through the Second-mentioned slots in the sides of the bolt, spring means of lesser strength than the first spring means mounted on said second pin and acting on said bolt to normally turn it in a direction opposite the direction of turning that the first spring means tends to turn the actuating member, and a member extending between and secured at its ends to the sides of the bolt against; which the roller bears and over the surface of which the roller relatively moves from one position in which it engages said member at its inner edge portion to another position in which it ongages a side of the member at a point substantially an arc distance of away therefrom.

2. A structure as defined in claim 1, said member carried by the bolt against which the roller engages comprising, a pin disposed parallel to the axis of said roller and spaced therefrom, said:

pin having a flat surface and adjacent edges of curved form, the axis of said roller, on movement of the actuating member and a traversing of the roller against the said member carried on the bolt with which it engages, to move the roller to engage said flat of said member, being carried across a line between the point of engagement of the roller with the said member and the axis of the rigid pin carried by said support.

3. In a latch mechanism, a supporting frame, a bolt member mounted on said frame, said bolt member being pivotable with respect to said. frame between a keeper engaging position and a cocked position and slidable with respect to said frame between said keeper engaging position and a keeper by-passing position, an actuator member mounted on said frame, said actuator member being pivotable with respect to said frame between a normal position corresponding to said keeper engaging position of said bolt member and an energized position corresponding substantially to' both said cocked position and said keeper by-passing position of said bolt member, the pivotal axes of said members being substantially displaced from each other, a coil spring circling the pivotal axis of said actuator member and urging said actuator member to pivot toward said normal position, and cam means comprising a pair of cooperable cam elements, one of said elements being mounted on said bolt member and one on said actuator member, said actuator member and said spring operating through said cam elements to hold said bolt member in said keeper engaging position and said cocked position and to urge said bolt member toward said keeper engaging position when said bolt member lies substantially intermediate said last-mentioned positions, and said actuator member and said spring operating to urge said bolt member from said keeper by-passing position toward said keeper engaging position.

4. In a latch mechanism, a supporting frame, a bolt member mounted on said frame, said bolt member being pivotable with respect to said frame between a keeper engaging position and a cooked position and slidable with respect to said frame between said keeper engaging position and a keeper by-passing position, an actuator member mounted on said frame, said actuator member being pivotable with respect to said frame between a normal position corresponding to said keeper engaging position of said bolt member and an energized position corresponding substantially to both said cocked position and said keeper by-passing position of said bolt member, the pivotal axes of said members being substantially displaced from each other, a coil spring circling the pivotal axis of said actuator member and urging said actuator member to pivot toward said normal position, and cam means comprising a pair of cooperable cam elements, one of said elements being mounted on said bolt member and one on said actuator member, one of said elements comprising a pin having a flattened surface and the other of said elements comprising a roller, said roller engaging said flattened surface of said pin when said bolt member is in said cocked position and said actuator member is in said energized position, said actuator member and said spring operating through said cam elements to hold said bolt member in said keeper engaging position and said cocked position and to urge said bolt member toward said keeper engaging position when said bolt member lies substantially intermediate said last-mentioned positions, and said actuator member and said spring operating to urge said bolt member from said keeper by-passing position toward said keeper engaging position.

5. In a latch mechanism, a supporting frame, a bolt member pivotably mounted on said frame, an actuator member pivotally mounted on said frame, the pivotal axes of said members being substantially displaced from each other, a coil spring circling the pivotal axis of said actuator member and urging said actuator member to pivot in one direction, and cam means comprising a pair of cooperable cam elements, one of said elements being mounted on said bolt member and one on said actuator member, said cam elements, said actuator member and said spring cooperating to hold said bolt member in a keeper engaging position and a cooked position and to urge said bolt member toward said keeper engaging position when said bolt member lies substantially intermediate said positions, one of said members having an arcuate slot extending through an arc of approximately about the cam element mounted on said one member, the cam element mounted on the other of said members extending through said slot, whereby the ends of said slot may serve as stops to limit the extent of relative movement of said members.

6. In a latch mechanism, a supporting frame, a bolt member pivotably mounted on said frame, an actuator member pivotally mounted on said frame, the pivotal axes of said members being substantially displaced from each other, a coil spring circling the pivotal axis of said actuator member and urging said actuator member to pivot in one direction, and cam means comprising a pair of cooperable cam elements, one of said elements being mounted on said bolt member and one on said actuator member, one of said elements comprising a pin having a flattened surface and the other of said elements comprising a roller and a shaft, said cam elements, said actuator member and said spring cooperating to hold said bolt member in a keeper engaging position and a cocked position and to urge said bolt member toward said keeper engaging position when said bolt member lies substantially intermediate said positions, said cam roller engaging said fiattened surface of said cam pin when said bolt member is in said cocked position, the one of said members having said cam pin mounted thereon having an arcuate slot extending through an arc of approximately 90 about said cam pin, said shaft for said cam roller extending through said slot, whereby the ends of said slot may serve as stops to limit the extent of relative movement of said members.

'1. In a latch mechanism, a supporting frame, a bolt member pivotally mounted on said frame, a spring biased actuator member pivotally mounted on said frame, the pivotal axes of said members being substantially displaced from each other, one of said members having an arcuate closed-ended slot, the other of said members having a portion fixedly positioned with respect thereto and extending through said arcuate slot, the engagement of said portion with the ends of said slot being effective to limit the pivotal movement of both of said members and a pair of cooperable cam elements, one of said elements being mounted on said bolt member and one on said actuator member, said cam elements and said actuator member cooperating to hold said bolt member in a keeper engaging position and in a cocked position and to urge said bolt member toward said keeper engaging member when said bolt member lies substantially intermediate said positions, one of said cam elements comprising a roller and the other of said cam elements comprising a pin having a flattened surface engageable by said roller when said bolt member is in said cocked position.

8. In a latch mechanism, a supporting frame, a bolt member pivotally mounted on said frame, a spring biased actuator member pivotally mounted on said frame, the pivotal axes of said members being substantially displaced from each other, one of said members having a closedended slot, the other of said members having a portion fixedly positioned with respect thereto and extending through said slot, said slot being contoured to permit substantially only simultaneous pivotal movement of said members, the engagement of said portion with the ends of said slot being effective to limit the pivotal movement of both of said members and a pair of cooperable cam elements, one of said elements being mounted on said bolt member and one on said actuator member, said cam elements and said actuator member cooperating to hold said bolt member in a keeper engaging position and in a cocked position and to urge said bolt member toward said keeper engaging member when said bolt member lies substantially intermediate said positions, one of said cam elements comprising a roller and the other of said cam elements comprising a pin having a flattened surface engageable by said roller when said bolt member is in said cocked position.

9. In a latch mechanism, a supporting frame, a bolt member mounted on said frame and pivotable with respect thereto between a keeper engaging position and a cooked position, a bolt actuating member mounted on said frame and pivotable with respect thereto between a normal position corresponding to said keeper engaging position of said bolt member and an energized position corresponding to said cocked position of said bolt member, the pivotal axes of said members being substantially displaced from each other, a main latch spring comprising a coil spring circling the pivotal axis of said actuating member and urging the actuator member toward said normal position, and cam means comprising a pair of cooperable cam elements, said cam elements comprising a cam roller rotatably mounted on one of said members and a cooperative element mounted on the other of said members, said cam elements being movable along arcuate lines which intersect each other substantially perpendicularly as said bolt member moves between said keeper engaging position and said cocked position and as said actuating member moves between said normal position and said energized position, the cam element mounted on said actuator member lying in the path of the cam element mounted on said bolt member and being in engagement therewith when said bolt member is in said keeper engaging position and said actuator member is in its normal position, and the cam element on said bolt member lying in the path of the cam element on said actuator member and being in engagement therewith when said bolt member is in said cocked position and said actuator member is in its energized position, said cooperative element having a substantial flattened area extending substantially parallel to the direction of movement of the cam element mounted on said bolt member and engageable with said cam roller when said bolt member is in said cocked position, whereby said cam roller may roll along said flattened area to permit corresponding movement of said bolt member with no substantial change in the bias of said main latch spring.

References Cited in the file of this patent UNITED STATES PATENTS Number

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