US2779618A - Refrigerator door latch - Google Patents

Description

Jan. 29, 1957 w, R. JEWELL REFRIGERATOR DOOR LATCH Filed Dec. 6, 1954 2 Sheets-Sheet l INVENTORL WILLIAM R. JEWELL Hi5 ATTORNEY Jan. 29, 1957 w. R. JEWELL 2,

REFRIGERATOR DOOR LATCH Filed Dec. 6, 1954 2 Sheets-Sheet 2 G3 INVENTOR. WILLIAM R. JEWELL HIS ATTORNEY REFRIGERATOR noon LATCH William R. Eewell, Lyndon, Ky., assignor to General Electric Company, a corporation of New York Ap cat D mb 1954, Ser al 3, 6

3 Claims. or, 292-332 My invention relates to door latches and more particularly to door latches for cabinets such as household refrigerators having relatively heavy doors.

A gasket of rubber or other resilient material is usually employed on refrigerator doors for sealing purposes. in order to obtain an adequate seal it is desirable that pressure be maintained on the gasket, and customarily this pressure is provided by means of the door latch. Heretofore rather heavy gaskets requiring a considerable compressive pressure or force have been employed, and in order to produce the needed compressive force the door latches have included a strong spring mechanism. Further, they have ordinarily included some means which insures that the door remains locked in the closed position against the compressed gasket. For example, in many latches a toggle mechanism is employed both to help close the door against the gasket and also firmly to lock the door in the closed position.

Because of the action of the toggle mechanism or other means which are used for this purpose it has been impossible or nearly impossible to open these latches by pushing the door from inside the refrigerator. Rather they can be opened only by means of the handle positioned on the outside of the door. As a result whenever a child has become accidentally locked in a refrigerator he has been unable to get cut. He cannot overcome the locking action of the latch by pushing from inside the refrigerator and hence unless released by some person outside the refrigerator may very well be asphyxiated. Recently, however, softer gaskets have been developed which do not require the large compressive force or the strong locking action neededwith the earlier types of gaskets. Accordingly, it is no longer necessary that latches providing a heavy closing force and a rigid locking action be used in all refrigerator cabinets.

It is thus a primary object of my invention to provide an improved refrigerator latch which may be opened by pushing the door from inside therefrigera'tor.

It is another object of my invention to provide a refrigerator latch including an improved, simplified arrangement for maintaining the latch in both its latching and its retracted positions.

It is a further object of my invention to provide a refrigerator latch including improved means for operating the latch from its latching position to its retracted position and vice versa.

In carrying out my invention I provide a door latch which is adapted to cooperate with a strike for latching a refrigerator door in a closed position. The latch comprises a supporting structure and a latch bolt which is pivoted on this structure to be movable between a latching position and a retracted position. The latch bolt includes a latching arm adapted to engage thestrike in its latching position and a control arm which is effective to move the latch between itspositions. The latch iurther includes an over-center mechanism which is etfective y s e i y t old bolt bot T ts tchin nd re States Patent" E 2,779,618

Patented Jan. 29, 1951 tracted positions. The over-center mechanism comprises a spring and a single link, which is connected between the bolt and the supporting structure, and the mechanism and the bolt are so constructed and arranged that the bolt may be moved to its retracted position and the door opened by pushing the door from inside the refrigerator. For normally opening the door from the outside, actuating means are provided which engage the control arm of the bolt. Upon the operation of the actuating means a force is applied to the control arm effective to overcome the force of the over-center mechanism and move the bolt from its latching to its retracted position. Upon the closing of the door the strike directly engages the control arm to snap the bolt from its retracted position back to its latching position.

The novel features which I believe to be characteristic of my invention are set forth with particularity in the appended claims. My invention, however, both as to its organization and method of operation, may be best understood by reference to the following description taken in conjunction with the accompanying drawings in which:

Fig. l is a horizontal sectional view of a door latching mechanism embodying my invention, the latching mechanism being applied to a refrigerator cabinet and shown in its latching position;

Fig. 2 is a vertical sectional view taken along the line 1-2 of Fig. l and showing the latching mechanism from the side;

Fig. 3 is a sectional view similar to Fig. l but showing the latching mechanism in its retracted position;

Fig. 4 is a horizontal sectional view of an alternate embodiment of my door latching mechanism, the mechanism being shown in its latching position;

Fig. 5 is a side view of the latching mechanism of Fig. a d

Fig. 6 is a sectional view similar to Fig. 4 but showing the latching mechanism thereof in its retracted position.

Referring now to Fig. 1 I have shown therein a latch 1 cmbodying'my invention in one form thereof. The latch is mounted within a refrigerator door 2 near one edge thereof. The door 2 includes an outer wall 3 and an inner wall 4 and the space between the outer and inner walls is filled with suitable heat insulating material (not shown). The door is mounted on a refrigerator cabinet 5 by suitable hinge means and a resilient gasket 6 is provided for sealing the door to the cabinet. This gasket is of a soft type requiring only a small compressive force and it is mounted by means of a flange 7 thereof, the fiange being secured between the inner and outer walls of the door. In the closed position of the door the gasket 6 is compressed between the door and the outer wall of the cabinet 5, and thereby effects a substantially air-tight seal therebetween. Although it is not shown, it will be understood that the cabinet 5 is of the type including spaced apart inner and outer walls, the space between which is filled with suitable heat insulating material such as fiber glass.

The latch 1 is adapted to engage a strike 3 mounted on the cabinet 5 in order to compress the gasket and hold the door in the closed position. Since the strike 8 may mounted on the cabinet by any Suitable means, no particular mounting arrangement is shown therefor. The latch itself is supported by means of a generally Ushaped supporting structure or bracket 9 which is affixed to the outer wall 3 of the door by means of a plurality of screws 10. To engage the strike 8 the latch includes a latch bolt 11 which is pivotally mounted on. the supporting structure 9. This latch bolt 11 has two identical, spaced apart, generel y v-sh ped perso a n 1 which are jo o her by twu ss p ece .2 nd t e Fig 2-) latch bolt includes a strike-engaging latching arm 14 and a control arm 15, the latching arms 14 being adapted to engage the strike 8 by means of a roller 17 mounted thereon, and the control arms being used to operate the latch bolt. The manner in which the control arms actuate the bolt will be more fully described hereinafter.

Referring to Figs. 1 and 3 it Willl be seen that only one of the two identical portions 11a and 11b of the latch bolt 11 are shown therein and thus only one latching arm 14 and one control arm 15 are shown. For this reason and also to aiford ease of description and understanding the latch bolt 11 will be spoken of hereinafter as having a single latching arm 14 and a single control arm 15 rather than as having two identical portions each containing such arms. In fact it should be obvious that the latch bolt could comprise a single member including one such latching arm 14 and one such control arm 15 rather than two identical joined together portions including such arms; and therefore as employed here1nafter the terms latching arm and control arm will be understood to refer not only to the illustrated bolt but also to the equivalents thereof.

The latch bolt 3-11 is pivotally mounted on the supporting structure 9 by means of a pivot pin 16 which extends through the arm 14 of the bolt intermediate the ends thereof. It is about the pin 16 that the bolt 11 is moved from its retracted to its latching position. The latching position of the bolt is shown in Fig. 1 and it will be noted that in this position the roller 1'7 mounted at the outer end of the arm 14 engages a ledge 13 at the head of the strike 8 in order to provide the locking action. Although a stationary member rather than a roller could be used to contact the strike, a roller is provided since it minimized friction to a considerable extent.

The bolt 11 is yieldably held in both its latching and its retracted positions by means of an over-center mechanism attached thereto. This over-center mechanism comprises a link 19 connected between the bolt and the supporting structure and a coil spring 20 disposed around the link. The link 19 is pivoted to the supporting struc ture at its lower or outer end (as viewed in Fig. 1) by means of a pivot pin 21, and at its upper or inner end it is connected to the latch bolt 11 adjacent the apex thereof by means of a pin and slot connection. Specifically, to form the pin and slot connection a slot 22 provided in the inner end of the link fits around a pin 23 mounted on the latch bolt adjacent the region where the arms 14 and 15 meet, i. e. adjacent the apex of the bolt. The spring 2t) which is disposed around the link bears at its opposite ends against two plates or washers 24 and 25 which also surround the link. These washers 24 and 25 are movable along the link, their travel being limited respectively by the pins 23 and 21. The action of the spring 20 is always to push against these washers and thus is always to try to force apart the pins 21 and 23. Since the position of the pin 21 is fixed on the supporting means, this means that the spring actually operates on the pin 23 and thus on the apex of the latch bolt itself.

The dead center position of the over-center mechanism formed by the link 19 and the spring 20 is that position where the pins 1.6, 21 and 23 all lie in a straight line. Whenever the pin 23 is moved slightly inwardly of this imaginary line through movement of bolt 11, the overcenter mechanism snaps the pin inwardly or upwardly as viewed in Fig. 1 and thereby moves the latch bolt to its latching position. Conversely, whenever by movement of the bolt it, the pin 23 is moved outwardly or below this imaginary line as viewed in Fig. 1, the spring forces the pin 23 to move still further downwardly and thereby carries the latch bolt to its retracted position. It will be noted that this outward or downward movement of the bolt is limited by a stop member 26 which is mounted on the supporting structure 9. This member 26 engages the latching arm 11.4 as shown in Fig. 3, so as to stop the outward travel of the bolt and determine its retracted position.

As shown in Figs. 1 and 3 and as indicated above, the over-center mechanism is effective to move the latch bolt to both its latching and retracted positions and to hold it therein. Specifically, in the latching position of the bolt the over-center mechanism is etfective to supply closing force to the door to compress the gasket 6. However, even though the latch bolt, as actuated by the overcenter mechanism supplies this compressive force, nonetheless the bolt and the over-center mechanism are so arranged that a child trapped within the refrigerator will be able to open the door by pushing from the inside. If a child trapped Within the refrigerator pushes against the door, a force is applied to the roller 17 tending to cause the pivoting of the latch bolt around the pin 16. In other words, when the child pushes against the door, a component of force is set up causing the latch bolt to move around the pivot 16 from its latching position to ward its retracted position. The spring 20 is of such strength that this component of force is etfective to overcome it, and thus as the child continues to push, the apex of the latch bolt, i. e. theportion in which pin 23 is mounted, moves outwardly. The outward movement proceeds under the childs force until pin 23 reaches it dead center position on the imaginary line between pins 16 and 21, or alternately stated, until the dead center position of the over-center mechanism is reached. At that point the over-center mechanism snaps over-center in the opposite direction moving the latch completely to its retracted position and freeing the child from the refrigerator.

For opening the door 2 under normal conditions, I have provided an improved means for cocking the latch, i. e. moving the latch bolt 11 from its latching to its retracted position. As shown in Figs. 1 and 3 this cocking mechanism includes a handle 27 which is pivoted on a flange 28 of the outer wall 3 of the door by means of a pin 29. The handle 27 at its one end bears against a latch cocking push rod 30 which is slidably mounted for in and out movement in a sleeve or bearing 31. The sleeve 31 is mounted in the wall 3 of the door adjacent the lower end of the control arm 15 of the latch bolt, and the push rod 30 extends completely through the sleeve and the wall and is provided with a flanged head 32 at its inner end. This flanged head 32, by my invention, bears against a pin or roller 33 which is mounted in and extends between curved slots 34 provided in the opposite walls of the supporting structure 9. The pin 33 in turn engages the control arm 15 of the latch bolt 11 adjacent the outer edge thereof and serves as the direct means whereby the bolt is actuated from its latching to its r tracted position.

When the handle 27 is actuated so as to move the push rod 30 inwardly, the head 32 bearing against the pin or roller 33 forces it to move inwardly in its slots 34. As the roller moves in its slots, it forces the arm 15 inwardly and thereby causes the bolt 11 to pivot on its mounting pin 16. This movement of the latch bolt continues as the roller 33 moves further upwardly in the slots until the latch bolt reaches the dead center position of the over-center mechanism. At that point the over center mechanism snaps the latch bolt to its retracted position shown in Fig. 3.

I have found that the provision of the roller 33 be tween the head 32 of the push rod and the control ann 15 of the latch bolt causes this cocking action of the latch to be accomplished with no binding and in fact very little friction at all. Due to its engagement with the sides of the curved slots 34 the roller turns or rolls as it moves inwardly and this greatly decreases the friction that would otherwise occur if the head of the push rod bore directly against the control arm i5. As a result a very smooth, even movement of the latch bolt is effected as it moves toward its dead center position. I have found, in fact, that noticeably less force is required from the handle 27 ime-1e 5 to co ck thelatch whenthe roller 33 is included-indie latch than when it is not.

in my improved latch the. control arm 'against which :the roller 33 moves to cock the latch bolt also serves as the means .for returning the latch bolt to its latching position as the door is closed; As may be seen-in'Fig. 3, with the latch bolt 11in its retracted position, the cross pieces 13 mounted at the outer end of the arm 15 are disposed to engage the outer end 35 of the strike 3 as the door is closed. This contact of the cross pieces at the outer end of: the arm 15 or in efi'ectthecontact of the outer end of the arm 15 itself causes. the bolt to move around its pivot 16 toward the latching position; The momentum of the door as it is closed provides sufiicient force to eitect this pivoting. Once the holtundenthe actuation of the control arm 15 reaches the dead center position, the over centermechanism then-snaps it to the latching position. Further, as the latch bolt isso moved or snapped toward its latching position under theforce of spring 23, the roller 17 engages the ledge fthlof the strike andpulls the door toward the cabinetto compress the gasket 6. Thus, it will be seen that thesame control arm 15 which serves as the means for cocking the latch bolt from its latching position to itsretracted position also serves. as the actuating means for returning the latch bolt to its latching positionas the door is closed. This, of. course, provides for a much simpler and less expensive latch than those conventional latches wherein additional linksand pivots aroused to close the latch besides those members needed to open the latch.

Referring now to Figs. 4, 5 and 6 I have shown therein an alternate embodiment of my improved latch. This latch 41 is designed to cooperaterwith a strike 42 to latch a refrigerator door in a closed position. The latch is mounted by means ofa generally U-shapedtsupporting structure whichit attached tothe outer wall 44 of a refrigerator door by means of a plurality of screws 45. The remainder of the refrigerator door other than the wall 44 is not shown since it will be understood that the door is similar to that shown. in Fig. 1. The strike 42 may be mounted on the main refrigerator cabinet (not shown) by any suitable means.

The latch 41 includes a pivoted latch bolt 46 which is movable between a latching position (shown in Fig. 4) and a retracted position (shown in Fig. 6). This latch bolt comprises twoidentical, spacedapart, V-shaped side portions 46a and 46b (see Fig. 5) each. including a control arm 47 and a latching arm 48. These two V- shaped portions 46a and 46b are joined together by means of two cross pieces 49 and St The cross pieces 4-9 connect together the latching arms 48 and cross pieces. 54 connect together the control arms 47. Sincethe two side portions 46a and 46b are identical and since. they both include a control arm and a latching arm, the latch bolt will hereinafter be described ashaving a single control arm 47 and a single latching arm 43. Only one control arm 47 and one latching arm 48 are shown in Figs. 4 and 6, and it is therefore believed that to refer to them in the singular affords both ease of description and increased understanding. Moreover, it will be obvious that the latch bolt could contain single unitary arms 4-7 and 48 rather than spaced apart portions forming such arms; and therefore as employed hereinafter. the terms latching arm and control arm will be understood to refer not only to the illustrated bolt but also to the equivalents thereof.

The means whereby the latch bolt on is supported on the bracket 4-3 comprises a pivot pin 51 which extends between the two sides of the bracket. This pin 51 pivotally supports: the bolt at a point. intermediate the ends of the latching arm 45. and the boltv rotates on the pin between its retracted and its latching, positions. In my improved latch, the bolt is yieldably held in both of these positions by means of an over-center mechanism. The over-center mechanism comprises a generally U-shaped link 5 2 whichis; connected'between the bolt 4.6 and-the supporting structure 43', and a spring 53: which is; also. connected between the bolt and the supporting structure... The link 52 is connected at its one end to the latch bolt 46 adjacent the-apex: thereof by means of a pivot. pin 54- and:

is-connected at its other end to the supporting, structure.

43 by means of apin and slot connection. Specifically, this pin and slot connection comprises slots 55 provided. in the opposite sides of the supporting structure 43 and a pin 56 attached to the link and movably mounted in the slots. The spring 53 is a tension member and is attached respectively at its opposite ends to the pin 51 mounting the latch bolt and the pin 56 forming: a

part of the aforesaid pin and slot connection. Hooked ends. provided on the spring are fitted over the pins to accomplish the mounting.

This over-center mechanism. in addition to yieldably holding the latch bolt 46 in both its retracted and latchingpositions is also effective to snap the latch bolt from one position to the other as it passes through.- the dead center position of the mechanism. The deadcenterposition lies on an imaginary lineconnecting the pivot pins 51 and 56. As the pin 54 at the apex of the latch bolt passes through this imaginaryline it is snapped in one direction or the other depending upon its direction of movement. Thus, if the bolt is being moved from its. latching position to its retracted position, as the pin 54' passes across this imaginary line the latch boltis then, snapped to the retracted position shown in Fig, 6. in,

other words, the spring 53 is effective to pull the latch bolt in that direction as the pin 54 passes dead center. Conversely, if the latch isbeing moved from the re tracted position to the latching position, as the pin 54 passes dead center, the tension spring is effective to pull the latch bolt to the latching position. in other words, as the pin 54-passes dead center the components of force. set upby the spring are changed so that the spring then tends to. move the latch bolt to and hold it in. the reverse position from that in which it was previously held The pin and slot connection, of course, permitsthe movement of the link 52 relative to the sup porting structure 43 necessary to effect this movement of the latch from its one position to the other. The link 52, itself limits the movement of the bolt as it moves tothe retracted position so that no separate stop is needed as in theernoodirnent of Figs. 1-3.

When the latch is in its latching position, the spring 53 provides the necessary force to compress a door gasket (not. shown). In other words, the spring 53 by exerting a force on the latch bolt causes the bolt to pull against the strike 42 so as to compress the gasket. Specifically a roller 57 mounted at the end of the arm 48 or" the latch bolt pulls against a ledge 53 or" the strike to cause this gasket compression. However, according to my invention, this gasket compressing force can be overcome by a child locked within the refrigerator. In other. words, a child; locked within the refrigerator by pushing against the door can release the latch bolt from its latching position; and get out of the refrigerator. When the child pushes against the refrigerator door he, or" course, causes a force to be applied to the roller 57. This force is in a direction to cause the arm 48 to pivot around the pin 51 and move the pin 54 toward the dead center position of the latch, and the spring 53 is of such strength that the childs force is able to overcome it. In other words, a component of force is set up when the child pushes against the door effective to move the latch toward its retracted position against the force of the spring As soon as the pig 54' reaches the dead center position, the latch bolt then snaps over to the retracted position completely releasing the door and allowing the child to walk ut ot t e r trisera et- 1 33131 5 latch s k th t h of Figs. 13 may be used on refrigerators without endangering the safety of any child.

For opening the latch under normal operating conditions, however, I have provided operating means which cock the latch by means of the control arm 47 of the latch bolt. These actuating means comprise a handle 59 which is pivoted to a flange 60 of the door casing 44 by means of a pivot pin 61. This handle at its one end bears against a push rod 62 which is slidably mounted in a sleeve or bearing 63 positioned in the Wall 44 of the door. The push rod 62 extends completely through the bearing and is provided at its inner end with a flanged head 64. In order to operate the latch, this head 64 bears against a pin 65 which is mounted in curved slots 66 provided in the opposite sides of the supporting structure43. This roller 65 in turn engages the outer end of the control arm 47 of the latch bolt.

When the handle 59 is operated it moves the push rod 62 inwardly against the pin 65. The pin 65 is thereby forced inwardly in the slots 66 pushing the arm 47 ahead of it. This movement of the arm 47 causes the latch bolt to pivot on the pin 51 until the pin 54 reaches the dead center position. At that time the spring 53 is effective to snap the latch to the retracted position of Fig. 6.

As with the embodiment of Figs. 1-3 described above, I have found that the inclusion of a roller, such as the roller 65, in the actuating means provides a much smoother cocking operation of the latch. Due to its engagement with the sides of the slots 66 the roller 65 turns or rolls as it is pushed inwardly in the slots by the push rod, and thereby it moves freely along the arm 47 of the latch bolt as it actuates the bolt. Thi action greatly reduces the friction over what it would be if no roller were present and thereby makes the latch much easier and smoother to cook. In fact, due to the inclusion of the roller in the actuating mechanism less force is required to cook the latch.

in addition to serving as the means for cocking the latch, the control arm 47 of the latch bolt 46 also serves as a means whereby the latch is returned to its latching position when the door is closed. When the door is closed with the latch in its retracted position, the cross pieces 50 at the outer end of the control arm 47 engage the outer end 67 of the strike 42. Or more generally, the outer end of the arm 47 engages the strike. Due to the momentum of the door this contact with the strike causes the latch bolt to pivot around the pin 51 until the dead center position of the latch is reached. At that point the spring 53 snaps the bolt 46 back to its latching position. Moreover, as the latch so snaps back to its latching position, the roller 57 engages the ledge 58 of the strike and thereby pulls the door in so as to compress the gasket. Thus, in this second embodiment as in the first embodiment described above, a single integral arm of the latch bolt serves as a means both for cocking the latch and for returning it to its latching position.

While in accordance With the patent statutes l have described what at present are considered to be the pre' (erred embodiments of my invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from my invention, and i, therefore, aim in the appended claims to cover all such changes and modifications as fall Within the true spirit and scope of my invention.

What 1'. claim as new and desire to secure by Letters Patent of the United States is:

1. A door latch for latching a refrigerator door in a closed position, said latch comprising a supporting structure, a latch bolt pivoted on said structure and movable between a latching position and a retracted position, said bolt having a strike-engaging latching arm and a control arm for moving said bolt between said positions, an overcenter mechanism effective yieldably to hold said bolt in said latching and retracted positions, said mechanism including a spring and a single link connected between said bolt and said structure, actuating means for moving said bolt from said latching position to said retracted position to permit opening of said door, said actuating means including slot means defined in said supporting structure, a roller mounted for rolling movement in said slot means and engaging said control arm, a push rod engaging said roller, and a pivoted handle for operating said push rod whereby said push rod forces said roller to move in said slot means against said control arm and operate said bolt from said latching position to said retracted position, said control arm upon the closing of said door engaging a strike to snap said bolt from said retracted position back to said latching position.

2. A door latch for latching a refrigerator door in a closed position, said latch comprising a supporting struc ture, a latch bolt pivoted on said structure and movable between a latching position and a retracted position, said bolt having a strike-engaging latching arm and a control arm for moving said bolt between said positions, an overcenter mechanism effective yieldably to hold said bolt in said latching and retracted positions, said mechanism including a single link connected between said bolt and said supporting structure and a compression spring disposed around said link, said link being connected at its one end to said latch bolt by a pin and slot connection and being connected at its other end directly to said supporting structure, actuating means for moving said bolt from said latching position to said retracted position to permit opening of said door, said actuating means including slot means defined in said supporting structure,

a roller mounted for rolling movement in said slot means and engaging said control arm, a push rod engaging said roller, and a pivoted handle for operating said push rod whereby said push rod forces said roller to move in said slot means against said control arm and operate said bolt from said latching position to said retracted position, said control arm engaging a strike upon the closing of said door to snap said bolt from said retracted position back to said latching position.

3. A door latch for latching a refrigerator door in a closed position, said latch comprising a supporting structure, a latch bolt pivoted on said structure and movable between a latching position and a retracted position, said bolt having a strike-engaging latching arm and a control arm for moving said bolt between said positions, an overcenter mechanism effective yieldably to hold said bolt in said latching and retracted positions, said mechanism including a single link and a tension spring, said tension spring being attached at its opposite ends to said bolt and said supporting structure and said link being connected at its one end to said supporting structure by a pin and slot connection and being pivoted at its other end directly to said latch bolt, actuating means for moving said bolt from said latching position to said retracted position to permit opening of said door, said actuating means including slot means defined in said supporting structure, a roller mounted for rolling movement in said slot and en gaging said control arm, a push rod engaging said roller, and a pivoted handle for operating said push rod Whereby said push rod forces said roller to move in said slot means against said actuating arm and operate said bolt from said latching position to said retracted position, said control arm engaging a strike on the closing of said door to snap said bolt from said retracted position back to said latching position.

References Cited in the file of this patent UNITED STATES PATENTS Trudeau Jan. 21, 1930

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