US2561201A

US2561201A - Refrigerator latch

Info

Publication number: US2561201A
Authority: US
Inventors: Francis M Hogg
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1947-10-31
Filing date: 1947-10-31
Publication date: 1951-07-17
Anticipated expiration: 1968-07-17

Description

July 17, 1951 F. M. HOGG 2,561,201

REFRIGERATOR LATCH Filed 001;. 31, 1947 25 Inventor: 2/ Francis Mfiogg,

His Attohney.

Patented July 17, 1951 REFRIGERATOR LATCH Francis M. Hogg, Findley Lake, N. General Electric Company, a

New York Y., assignor to corporation of Application October 31, 1947, Serial No. 783,245

11 Claims.

My invention relates to door latches and more particularly to such latches for cabinets such as household refrigerators havin relatively heavy doors.

A gasket of rubber or similar resilient material is usually employed on refrigerator doors for sealing purposes. In order to provide an adequate seal, it is desirable to maintain pressure on the gasket. Secondly, it is desirable to avoid the necessity of slamming the refrigerator door to secure sufllcient force to effect this seal because of the danger of disturbing the contents of the refrigerator. Both of these requirements may be accomplished with latches which are cocked in the open position and which are automatically tripped by relatively small forces to the latched position when the door is closed.

Accordingly, it is an object of my invention to provide an improved latch of the trip type.

It is another object of my invention to provide a latch including an improved arrangement for maintainin the latch in both its latched and its retracted positions.

Further objects and advantages of my invention will become apparent as the following description proceeds, and the features of novelty which characterize my invention will be pointed out with particularity in the claims annexed to and forming part of this specification.

For a better understanding of my invention, reference may be had to the accompanying drawing in which Fig. 1 is a sectional plan view of a door latching mechanism embodying my invention applied to a refrigerator cabinet; Fig. 2 is a vertical sectional view taken along the line 2-2 of Fig. 1; and Fig. 3 is a sectional view similar to Fig. 2 showing the latch in its retracted position.

Briefly, the latching mechanism illustrated in the drawing comprises a latch mounted on the door and arranged to engage a strike mounted on the stationary cabinet structure. The latch bolt is carried by a pair of pivoted links for movement between its latching and its retracted positions. An over-center spring is employed in conjunction with the links for positively holding the latch bolt in either of th above two positions. A trigger or trip member is provided for engaging a strike during the closing movement of the door to move the latch toward its latching position. The latch is constructed so that the latch bolt not only has a generally reciprocating motion substantially parallel to the face of the strike but also a motion in a direction substantially perpendicular to the face of the strike to secure the required gasket pressure.

Referring now to Fig. 1, the latch I is mounted within a refrigerator door 2 near the edge thereof. The door 2 comprises an outer wall 3 and an inner wall 4, the space between the outer and the inner walls being filled with suitable heat insulating material (not shown). A resilient gasket I is provided for sealing the refrigerator cabinet, a flange 6 of the gasket being positioned between the inner and the outer walls of the door. The refrigerator cabinet comprises an outer wall I and an inner wall 8, the space between the walls being filled with suitable heat insulating material (not shown). A breaker strip 9 of heat insulating material is provided for closing the space between the inner and outer walls adjacent the door opening of the refrigerator. The gasket 5 is pressed between the door and the'outerwall of the cabinet in the closed position of the door.

A strike I0 is mounted on the cabinet f r engagement with the latch I. A mounting bracket II is secured between the inner and outer walls of the cabinet, and the strike is supported on the bracket II by a screw I: or any other suitable fastening device. In order to move the latch from its latching position, a handle I! is provided on the door 2. The handle mechanism includes a base plate It which is secured to the outer wall 3 of the refrigerator door by screws l5 and It or by. other suitable fastening devices. The handle is biased to the position shown in Fig. 1 by a spring I! which presses against a cross-piece ll of the handle. The spring I! is coiled about a pin l9 which is mounted on two outwardly extending lugs, one of which is shown at 20; these lugs are secured to or may be integral with the base plate H. When the handle is moved outwardly from the refrigerator door the cross-piece it of the handle engages a plunger 2| and presses the plunger inwardly to actuate the latching mechanism. An escutcheon 22 is provided for concealing the base of the handle and the plunger and for giving a finished appearance to the front of the door. The escutcheon is hooked under the left edge of the base plate II and is snapped under the outwardly extending right edge of the plate It.

A bracket 23 is provided for mounting the latch securely within the refrigerator door. This bracket is secured to the inner side of the outer wall of the refrigerator door by the screws II and It. An inwardly extending portion 24 of the mounting bracket 23 is secured to a lug 25 by a screw 26 or other suitable fastening means, and the lug is secured by welding or in any other suitable manner to an inwardly extending flange 2'! of the outer wall of the refrigerator door. In order to prevent the heat insulating material between the inner and outer walls of the door from working into the moving parts of the latch, an enclosure 28 of heat-insulating material is ar ranged to substantially surround the latch.

Referring now to Fig. 2, the latch includes a supporting structure or bracket 29 which is of generally U-shaped cross-section. The bracket 29 is secured to the mounting bracket 23 by screws A second link 35, also U-shaped, is mounted on pin 33 for rotation thereabout. In order to retain the door in its closed position, a latch bolt 36 is carried by the two 31 and 38 respectively, which extend between the two sides of the U-shaped links. The latch bolt 36 is of channel shape, and aroller 39 is mounted at one end of the latch bolt in order to facilitate movement of the latch bolt when in contact with the strike Ill. The latch bolt is moved forcibly to its'latching position and to its retracted position and the bolt is maintained in either of these positions byqan over-center spring 46; The over-center spring 40 further provides force for firmly pressing the latch bolt 36 against the face .of the strike ID in order to maintain the gasket under the required sealing pressure. The over-center spring 46 is supported on a connecting link 4| which retains the spring in its movement. between its tracted positions. One link. is mounted on the fixed pivot pin 32, and the other end is mounted on a movable pin 42 which extends between the two sides of the U-shaped link 35. This end of the connecting link has an elongated slot 43 for providin the necessary lost motion between the connect ing link and the link 35 during theoperation of the latch. One end of.the over-center spring. '40. presses against a shoulder formed on the connecting link 4|, and the other end presses against the pin 42.

The plunger 2| is'mountedjorsliding movement in a tubular conduit 45 which is secured to the supporting structure 29 by welding or in any other suitable manner and extends outward- 13! through the outer wall of the door, as shown in Fig. l. The link 34 includes a flat plate portion or cross-piece 46 which is disposed adjacent theinner end of the plunger 2|. Movement of the plunger thereby may be utilized to cause a rotational movement of the link 34 for actuating the latch in a manner hereinafter to be described. In order to move the latch from its retracted position there is provided a trigger or trip member 41 having a strike-engaging portion 48 disposed adjacent to a front surface 48 of the 'strike I6. 48 of the trigger is disposedadjacent the crosspiece 46 of the link 34, so that movement of the trigger may be utilized to effect rotation of the link 34 and operation of the latch. The opposite end of the trigger is formed with a flat surface 5,0 which is arranged to engage the base of the supporting structure 28 in the retracted position of the latch and thereby limit the movement of the latch under the influence of the over-center spring 40.

The operation of the latch is as follows. The latch is shown in its latching position in Figs. 1 and 2. When it is desired to open the door the handle I3 is moved outwardly from the face of the door causing the cross-piece 18 of the handle to press the plunger inwardly against the crosspiece 46 of the link 34. This causes a clockwise rotation of the link 34 as viewed in Fig. 2, about thepivot pin 32. ,The rotation of the link .34 causes a movement of the latch bolt 36 upwardly

links

34 and 35 by p ns.

latching and its reend of the connecting The strike-engaging portion upwardly toward. the position 25, position shown in Fig.

and to the right because of the engagement of the 34 with the latch bolt through the pin 31. Since the latch bolt is also in engagement with the link 35 through the pin 38, movement of the link 34 has the additional eflect of causing a corresponding clockwise rotation of the link 35. As the movement of the link 35 proceeds, the pin 42 moves the connecting link 4| shown in Fig. 3, carrying with it the over-center pin 42 ultimately passes beyond a line extending between the fixed pivot points 32 and 33, allowing the spring 48 to pass over-center, that is, shifting the line of force exerted by the spring to the opposite side of the line extending between the pivot points 32, 33. The over-center movement of the spring 46 results in arapid clockwise movement of the link 35 completing the movement of the latch bolt 36 to the retracted position shown in Fig. 3. The overcenter spring thereafter maintains the, latchiin the open or retracted position, and the handle may be released and allowed to 'move back to the 1 under the influence of the spring l'l without any eifect upon the position of the latch mechanism.

During its clockwise rotation the, cross-piece, 46 of the link 34 engages the strike-engaging portion 48 of the trigger and moves the trigger in a clockwise direction about the pivot pin 32.

As the spring 40 moves over-center to the position shown in Fig. 2, the flat surface 56 of the trigger is moved intoengagement with the base of the supporting structure 28 to prevent movement of the latch in the retracted position beyond the position "shownin Fig. 3, and the portion 48 of the trigger is positioned for engaging the strike l6 during the closing of the door.

As the 'dooris moved' toward its closed position, the portion 48 of the trigger 41 comes into contact with the front surface 48v of the strike in. Since the portion 48 of the trigger is in engagement with the cross-piece 46 of the link 34. closing pressure on the door causes the link 34 to be moved in a counterclockwise direction from the position shown in Fig. 3. This causes movement of the latch bolt 36 tothe left, as viewed in Figs. 2 and 3, and the latch bolt carries with it v the link 35, rotating that link in a counterclockwise direction about its pivot point 33. The

counterclockwise rotation of the link 35 causes the pin-42 to shift the connecting link 4| downwardly toward the positionshown in Fig. 2, the

pin 42 moving along the slot 43 in the connecting link. .As this movement continues, the pin 42 ultimately passes below a'line extending between the fixed pivot points 32 and33, shifting the spring 48 over center, that is, shifting the line of force exerted by the spring to the opposite side of the line extending between the pivot points 32, 33. The spring 44, in moving over-' center, causes a rapid further counterclockwise movement of the link 35. This movement of the link 35 is transmitted to the latch bolt 36 cansing a rapid final movement of the latch boltto the closed position independent to any actuation of the link 34 by the trigger 41. The over-center spring thereby maintains the latch bolt in its latching position and by the force transmitted through the link 35 to thelatch bolt, also maintains the proper sealing pressure on the gasket 5.

The maintenance of the proper sealing pressure on the gasket 5 is secured'by the particular construction and arrangement ,of the links 14 and 35'. These links are so constructed that the spring 46. The

length of the arm of the link 34 between its fixed pivot point 32 and its connection to the latch bolt at 31 is greater than the length of the arm of the link 35 between its fixed pivot point 33 and its connection to the latch bolt at 38. By a comparison of Figs. 2 and 3 it can be seen that because of this construction the pin 38 must move through a greater angle than the pin 37. This results in a substantial decrease in the distance between the pin 38 and a base of the supporting structure 29 in moving from the latching position shown in Fig; 2 to the retracted position shown in Fig. 3. The corresponding movement of the longer arm of the link 34 results in a smaller variation in the vertical distance from the pin 31 to the base of the supporting'structure 29. Further, since the link 34 is arranged so that a line through the

points

32 and 31 in the latching position is further to the left of a line through the pin 32 perpendicular to the base of the supporting structure 29 than the line between the

points

32 and 31 is to the right of such perpendicular line in the retracted position, the pin 3'! is actually slightly farther from the base of the supporting structure in the retracted position than in the latching position of the mechanism. On the other hand, since the link 35 must move through a much greater angle because of its shorter arm, a line through the

points

33 and 38 in the retracted position is farther to the right of a line L through the pin 33 perpendicular to the base of the supporting structure than the line through the

point

33 and 38 is to the left of such perpendicular line in the latching position. Consequently, the pin 38 is closer to the base of the supporting structure in the retracted position than in the latching position. Because of the above-described construction and arrangement of the

links

34 and 35, the latch bolt in the retracted position is inclined upwardly so that the roller or strike-engaging end of the latch bolt is located at a substantially greater distance from the base of the supporting structure 29 in a retracted position shown in Fig. 3 than in the latching position shown in Fig. 2. Thus, as viewed in Figs. 2 and 3, the roller or strike-engaging end of the latch bolt 33 moves downwardly in shifting from the retracted to the latching position and thereby presses against the face 5| of the strike to cause pressure .to be applied to the gasket 5. As a further contributing factor toward securing a proper gasket pressure the link 34 is so arranged on its pivot 32 that, during the I final closing movement of the latch, the pin 31 by which the link is connected to the latch bolt is moving downwardly from the high position it occupies when the line through the

points

32 and 31 extends in a direction perpendicular to the base of the supporting structure 29. This assists in imparting a component of motion to the latch bolt 35 in a direction perpendicular to the face 5| of the strike l0 and thereby assists in applying the proper pressure to the gasket 5. A further factor in securing the proper pressure on the gasket is the construction of the latch engaging face 5| of the strike. This face is inclined downwardly to the right as viewed in Figs. 2 and 3, so that the latch bolt, in moving to the left toward its latching position, must ride up this inclined surface thereby exerting an increasing pressure against the face of the strike.

While I have shown and described a specific form of my invention applied to a refrigerator, I do not desire my invention to be limited to the particular construction shown and I intend by the appended claims to cover all modifications other of said links, and means for actuating said one of said links to move said latch bolt toward its retracted position, said other of said links being actuated through said latch bolt in-re sponse to the actuation of said one of said links to shift said other end of said spring to one side of a line extending between the pivot points of said links for moving the line of force of said spring over center with respect to a line extending between said pivot points of said links tov retain said latch bolt in its retracted position.

2. A door latch comprising a supporting structure, a pair of spaced links pivotally mounted on said structure, a latch bolt carried by both of said links, an elongated over-center spring having one end disposed at the pivot point of one of said links and the other end engaging the other of said links, means for actuating said one of said links to move said latch bolt toward its retracted position, and means for actuating said one of said links to move said latch bolt toward its latching position, said other of said links being actuated through said latch bolt in response to the actuation of said one of said links to shift said other end of said spring to either side of a line extending between the pivot points of said links for moving the line of force of said spring over center with respect to a line extending between said pivot points of said links to retain said latch bolt in its retracted and its latching positions.

3. A door latch comprising a supporting structure, a pair of spaced links pivotally mounted on said structure, a latch bolt carried by both of said links, means for actuating one of said links to move said latch bolt toward its retracted position, means for moving said latch bolt toward its latching position, and an elongated over-center spring having one end disposed at the pivot point of one of said links and the other end engaging the other of said links, said other of said links being actuated through said latch bolt in response to the actuation of said one of said links to shift said other end of said spring to either side of a line extending between the pivot points of said links for moving the line of force of said spring over center with respect to said line extending through said pivot points of said links to hold said latch bolt in both its retracted and its atching positions.

4. A door latch comprising a supporting structure, a pair of spaced links pivotally mounted on I said structure, a latch bolt carried by both of said links, means for actuating one of said links to move said latch bolt toward its retracted position, means for actuating said one of said links to move said latch bolt toward its latching position, and an elongated over-center spring having one end disposed at the pivot point of one of said links and the other end engaging the other of said links, said other of said links being actuated through said latch bolt in response to the actuation of said one of said links to shift said other end of said spring to either side of a line extending between the pivot points of said links for moving the line of force of said spring over center pivot points of said links to hold said latch bolt I in both its retracted and its latching positions.

I 5. A door latch comprising a supporting structure, a pair of spaced links pivotally mounted on said structure, a latch bolt carried by both of said links, a connecting link extending between said pair of links, said connecting link having one end mounted at the-pivot point of one of said spaced links and having an elongated slot at its other end for providing a lost motion connection with the other of said spaced links, an elongated over-center spring surrounding said connecting link, and means for actuating one 01 said pair of links to move said latch bolt toward its retracted position, the other of saidpair of links being actuated in response to the actuation of said one link to shift said other end of said connecting link relative to the pivot point of said other of said spaced links for moving the line of force of said spring over center with re-v spect to a line extending between said pivot points of said links to retain said latch bolt in its retracted position.

6. A door latch adapted to engage a strike and comprising a supporting structure, a pair of spaced links pivotally mounted on said structure, a latch bolt carried'by said links, means for actustrike-engaging position by said one of said links during the actuation of said one of said links for moving said latch bolt toward its retracted posiating one of said links to move said latch bolt toward its retracted position, a trigger adapted to contact the strike during closing movement of the door for actuating said one of said links to move said latch bolt toward its latching position, an elongated over-center spring havin One end disposed at the pivot point of said one of said links and the other end engaging the other of said links, and means for moving said other end of said spring to opposite sides of a line extending through the pivot points of said links to maintain said latch bolt in its retracted and its latching positions.

7. A door latch adapted to engage a strike and comprising a supporting structure, a pair of spaced links pivotally mounted on said structure, a latch bolt carried by bothof said links, an elongated over-center spring having one enddisposed at the pivot point of one of said links and the other end engaging the other of said links, means for actuating one of said links to move said latch bolt toward its retracted posltion.

9. A door latch adapted to engage a strike and 'comprising a supporting structure} a pair of spaced links pivotally mounted on said struc- .ture, a latch bolt carried by said links, means for actuating one of said links to move said latch bolt toward its retracted position, and a trigger adapted to engage the strike to move said latch bolt from its retracted position toward its latching position, said trigger including means for engaging said supporting structure to limit the movement of said latch bolt in its retracted position.

10. A door latch adapted to engage a strike for holding a door closed under pressure, said latch comprising a supporting structure, a pair of spaced links pivotally mounted on said structure, a latch bolt carried by said links and having a component 01 motion along a line generally parallel to theengaging surface of the strike between retracted and latching positions, the length of one of said links between its pivot point and its connection to said latch bolt being greater than the length of the other of said links between its pivot point and its connection to said latch bolt whereby a component of motion in a direction generally perpendicular to the engaging surface of the strike is imparted to said latch bolt v holding a door closed under pressure, said latch tion, movement of said latch bolt by said one of in its retracted position, and a trigger adapted to contact the strike during the closing move ment of the door for actuating said oneof said links to move said bolt toward its latching position, movement of said one of said links being efiective to shift said other of said links for moving said other end of said spring to the opposite side of said line extending between said pivot points of said links to actuate said latch bolt forcibly to its latching position.

8. A door latch adapted to engage a strike and comprising a supporting structure, a pair of spaced links pivotally mounted on said structure, a latch bolt carried by said links, means for actuating one of said links to move said latch bolt toward its retracted position, and a trigger adapted to engage the strike for moving said latch bolt from its retracted position toward its latching position, said trigger being moved to comprising a supporting structure, a pair oi. spaced links pivotally mounted on said structure, one of said links being disposed adjacent the strike and the other of said links being disposed remote trom said strike, and a latch bolt carried by said links and having a portion for engaging the strike, the arm of said adjacent link between its pivot point and its connection to said latch' bolt being longer than the arm of said remote link between its pivot point and its connection to said latch bolt 'whereby during movement of the latch to latching position the end of the latch bolt remote from the strike is raised relative to the end adjacent the strike to press said latch bolt against said strike for maintaining the door closed under pressure.

FRANCIS M. HOGG.

, REFERENCES CITED The following references are of record in the file or this patent:

UNITED STATES PATENTS Number Name Date 1,700,747 Roedding et a1. Feb. 5, 1929 2,016,519 Schmidt Oct. 8, 1935 2,039,873 Andersen et a1. May 5, 1936 2,334,065 Burke Nov. 9, 1943 FOREIGN PATENTS Number Country I Date 110,069 Switzerland Aug. 17, 1924