US3373733A - Oven door hinge - Google Patents

Description

March 19, 1968 R. w. HARRINGTON 'ET AL 3,373,733

OVEN DOOR HINGE Filed Sept. 25, 1966 5 Sheets-Sheet 1 FIG. 2

INVENTORS ROBERT W. HARRINGTON WILLIAM C. COVEY BY GEORGE MAC ARTHUR JR.

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ATTORNEYS March 19, 1968 R. w. HARRINGTON ET AL 3,373,733

OVEN DOOR HINGE Filed Sept. 23, 1966 3 Sheets-Sheet 2 INVENTORS ROBERT W. HARRINGTON WILLIAM C. COVEY BY GEORGE MAC ARTHUR JR.

(WWW fl im m ATTORNEYS FIG. 4

March 19, 1968 Rw, HARRINGTON ET AL- 3,373,733

OVEN DOOR HINGE Filed Sept. 23, 1966 5 SheetsSheet 25 Z I Q I 2 LL] I U I I O. U) M I Z 2 I I d I (I I i I I INVENTORS M ANGLE OF DOOR POSITION BY GEORGE MACARTHUR F|G.9 Co; and M ATTORNEYS 3,373,733 OVEN DOOR HINGE Robert W. Harrington, William C. Covey, and- George McArthur, Jr., Delaware, Ohio, assignors to Sunray Stove Company, Delaware, Ohio Filed Sept. 23, 1966, Ser. No. 581,478 13 Claims. (Cl. 126191) ABSTRACT OF THE DISCLOSURE The invention disclosed in this application relates to an oven door hinge and, more particularly, to a hinge for a lift-ofi door wherein the structure of the hinge permits of the obtaining of all spring forces from a single spring which reaches a valley point of tension at the lift'off point and wherein the spring tension and the spatial relationship among the hinge elements remain substantially constant during removal and replacement of the door. The spring closing force acting on the door at the broil position is opposed not only by gravity but also by a cam surface.

Background Doors of cooking ovens are usually quite heavy, and persons using such doors can experience ditliculty and inconvenience, particularly if they are required to lift the full weight of the door upon closing it. Many mechanisms have been devised to aid in the closing of oven doors, and most comprise springs which function to oppose the weight of the door. In this connection, Stoligrosz et al., in US. Patent No. 3,072,117, and Mills in US. Patent No. 2,539,151 for example, have suggested the use of torsion coil springs in oven door closure mechanisms.

Similarly, the practice has long existed to provide means which allow the door to rest at a preselected equilibrium position between its completely open and completely closed position so that the door can be easily maintained in a desired partially opened position. The equilibrium position is herein denoted the broil position. Prior to our invention, the means for providing a broil stop usually consisted of an extra spring in the hinge mechanism to hold a roller against a cam. The surface of the cam generally had either a raised portion or an indentation. When an oven door which includes such a device is being pushed toward its closed position, the roller rolls into the indentation or rides up on the raised portion. In this manner, the door comes to an equilibrium position where it will remain partially open until it is pushed farther to the fully closed position or until it is pulled back toward the open position.

For one to be able to remove a door from the oven in some facile manner has long been recognized as a desirable convenience for the cleaning of the oven and for other purposes. Many doors; such as that described by Reeves in US. 2,592,333; are subject to removal in any one of several positions. Many doors require the unfastening of a spring, or similar manual procedure, before they can be removed.

Furthermore, many oven doors, when once removed from the oven, are difficult to replace. They often require extensive manipulation to properly position them on the oven, especially when the removal of the door has reatent 3,373,733 Patented Mar. 19, 1968 sulted in a changed tension in a spring or a changed spatial relationship among the elements of the door and hinge. These manipulations have proven difficult for a housewife, especially in those instances where she is required to perform them when holding the weight of the door.

Objects Therefore it is an object of our invention to provide an improved hinge for an oven door.

A further object of our invention is to provide a single torsion spring inside an oven door to simultaneously provide all spring forces necessary.

A further object of our invention is to provide means which will allow easy removal of the door in one selected position while preventing its removal in any other position.

A further object of our invention is to simplify the replacement of the door, when once removed, back onto the oven.

A further object of our invention is to provide a hinge mechanism which will allow the complete oven door and hinge mechanism to be assembled independently of the main manufacturing assembly line.

It is a specific object of the invention to provide a hinge for an oven door which effects a valley point of spring tension at a broil stop position, the door being removable from the oven at only such position and under conditions of a constant spring tension and a constant spatial relationship among hinge elements during removal and replacement of the door.

The foregoing and related objects can be attained in a hinge for the door of an oven for supporting said door as it is opened and closed, and for supporting said door at a broil position intermediate the doors fully open and fully closed positions, said oven having structures fixed thereto for engaging elements of said hinge; said hinge comprising: (1) pivot means upon which said door pivots as it opens and closes; (2) a link member provided with a cam follower, said cam follower being movably secured to said door for circular movement therewith, and for radial movement with respect to said pivot means; (3) a torsion spring cooperative with said door via said link member, said spring adapted to be under tension at all positions of said door, and said tension acting on said door in a direction toward said doors closed position; (4) a cam fixed relative to said pivot means and operable when said door is in said broil position; said cam being positioned to engage said cam follow'er when the door is being moved in a closing direction to said broil position; and operates in a manner to effect outward radial movement of said cam follower as the door moves on through and past the broil position; (5) an outstop arm extending from and fixed to the inner side of said door and adapted for sliding engagement with said oven structures when the door is being moved from non-broil positions (where said structures obstruct the removal of said arm from said oven) to a broil position (where said arm can be lifted free of said structures); and (6) supporting means with a fixed position relative to said pivot means and said cam and adapted to removably engage said oven structures; whereby said door and hinge can be removed from and returned to said oven at only said broil position and when said spring is at a valley point of tension, thus preventing a change in spring tension and a change in spatial relationship between said door, said cam follower, said supporting means, and said cam during such removal and return.

A feature of the hinge of the invention is a provision for (1) elements which are fixed relative to the door and which have a specifically determined permissible vertical translational movement relative to certain oven structures at intermediate positions of the door as the door moves circularly in opening and closing; (2) elements which are fixed relative to said oven structures and require a specific vertical translational movement of the elements fixed relative to the door for disengagement from said elements fixed relative to the oven structures; and (3) a co-acting spring mechanism which permits the maintenance of the spatial relationship among all such elements at the broil position whether said hinge and door are on or off the oven.

Another advantage of our invention is that no spring is located in the hot area around the oven liner. This increases the life of the springs used.

Further objects and features of the invention will be apparent from a consideration of the following description taken together with the accompanying drawings illustrating preferred embodiments of our invention.

In the drawings:

FIG. 1 is a diagrammatic representation of a range and oven which includes the door hinge of the invention;

FIG. 2 is a view in perspective of a hinge constructed according to our invention;

FIG. 3 is also a view in perspective of a hinge constructed according to our invention, FIG. 3 showing the back of the hinge shown in FIG. 2;

FIG. 4 is a plan view, partly in section, showing the preferred cam follower element of our hinge;

FIG. 5 is a diagrammatic View, in side elevation, of a portion of the outstop arm of the invention in its position relative to a locating pin when the oven door is fully open;

FIG. 6 is a view similar to that of FIG. 5 except that the position of the outstop arm is shown when the oven door is fully closed;

FIG. 7 is a view similar to that of FIG. 5 except that the position of the outstop arm is shown when the oven door is in a position intermediate its fully open and its broil positions;

FIG. 8 is a view similar to that of FIG. 5 except that the position of the outstop arm is shown when the oven door is in its broil position; and

FIG. 9 is a graph illustrating the dependence of spring tension on the door position.

Description Referring more particularly to the drawings, we show in FIG. 1 door hinges indicated generally by 12, cooperating with an oven door 14 positioned in the oven portion 16 of a stove or range 18. Hinges 12, one of which is shown in more detail in FIGS. 2 and 3, comprise a pivot rod 20 upon which the door 14 pivots as it is opened and closed. The pivot rod 20 is secured to a supporting arm 22, the latter including two hook portions 24 and 26 and an upwardly-facing cam 28.

The supporting arm hook portions 24 and 26, as shown in FIG. 3, for example, are hooked over vertically spaced locating pins 30 and 32 which are secured to the oven wall just inside the door opening.

A torsion spring 34 is positioned around the pivot rod 20, one end of the spring 34 being secured to a sleeve 36 which can be secured to the pivot rod 20 by means of a set screw 38. The other end of the spring 34 is secured to a spring link member 40 by inserting the end of the spring 34 through a hole 42 in the link member 40, or in any suitable manner.

A hinge panel 44 is secured to the door 14 and is provided with a substantially circular hole 46 near its bottom end, the pivot rod 20 being positioned for rotation of the hole 46 for pivotal motion of the panel 44 about the rod 20.

The hinge panel 44 is also provided with a slot 48 through which is inserted a bolt 50, the latter securing the upper end of the spring link member 40 for simultaneous movement therewith.

An outstop arm 52 extends outwardly from the panel 44 (but inwardly with respect to the oven 16). The outstop arm 52 has an upturned hook portion 54 at its end which is adapted to hook onto the upper pin 30 when the door is in its fully open position (see FIG. 5). The outstop arm 52, as shown, has a unique shape, the upper and lower arcs, defining the upper and lower edges thereof, being shaped such that as the door 14 is opened or closed there is a change in the distance (indicated by the distance X in FIGS. 7 and 8) between the upper edge of the outstop arm 52 and the upper pin 30. The distance X is the distance the outstop arm 52 can be lifted in vertical translational movement without being obstructed by the upper locating pin 30. The distance Y represents the distance which the hook 24 must be raised over the pin 30 to effect its clearance when the door is being removed. At all positions of the door, except at the doors broil position, the distance X is smaller than the distance Y (see FIGS. 5, 6, and 7) and the outstop arm 52 cannot be raised high enough to permit clearance of the hook 24 over the pin 30 or clearance of the hook 26 over the pin 32. Actually, at the doors fully open position (FIG. 5) and at the doors fully closed position (FIG. 6), the distance X is substantially zero. At the doors broil position, however, the distance X is greater than the distance Y and the outstop arm 52 can be lifted vertically high enough to permit the hooks 24 and 26 to clear their respective locating pins 30 and 32.

FIGURE 4 shows the preferred cam follower. Other types, including non-rolling types, could be used. As shown in FIG. 4, a roller 56 is secured to bolt 50 which is inserted through slot 48 in panel 44. A nut 50a is provided for bolt 50. A rivet may be used instead of a bolt. The roller 56 is adapted to ride on the cam 28 as the door 14 passes through and past its broil position in a closing direction. A flange (or nut) 58 on the bolt 50 se4rves to hold the roller 56 in position against the panel 4 It may be noted that door 14, outstop arm 52, supporting arm 22, cam 28, and pivot rod 20 are all fixed relative to each other insofar as vertical translational movement is concerned, although the elements 14 and 52 may rotate relative to elements 22 and 28.

Operation When the door 1 4 is first positioned on the oven 16,- a suitable tension is placed on the torsion spring 34 by rotating the sleeve 36. A suitable tension is one which nearly oifsets the weight of the door at the fully open position and which can force the door to its broil position from an intermediate position between the broil position and the fully open position. This tension, as will appear hereinafter, will not cause roller 56 to ride up cam 28.

When a desired tension is attained, the sleeve 36 is secured to the pivot rod 20 by means of the set screw 38.

If the door is fully open, as shown in FIG. 1, the gravity pull or weight of the door overbalances the tension of the spring and releasably holds the door open at the same time, the book 54 of outstop arm 52 is hooked on the upper locating pin 30 (FIG. 5) and the bolt 50, with roller 56, is at the bottom of the slot 48, the bottom of the slot being the end toward the pivot rod 20. As the door moves from its fully open position toward the broil position, tension on the spring 34 reduces, bolt 50 remains at the bottom of the slot 48, and outstop arm 52 rides inwardly between locating pins 30 and 32, resting on lower pin 32.

When, during the closing of the door 14, the roller 56 engages the cam 28, the bolt 50 is moved in the slot 48 radially outwardly with respect to the pivot rod 20. This latter motion pulls the spring link member 40 radially outwardly and thus tightens the springs 34. In this manner, spring tension, which had been decreasing during the closing of the door, starts to increase at the broil position; that is, when the roller 56 starts to ride up the cam 28. Thus, the spring tension has a valley point of tension at the broil position and the spring resists any effort to displace the door from this position toward the closed position. So, the door is releasably held in the broil position.

As the door continues to be closed, after it has passed the broil position, the roller rides down the rear of the cam (toward the position 49), the bolt 50 returns to the bottom end of the slot 48, the spring link member 40 moves radially inwardly, and the tension on the spring again reduces progressively. However, when the door is fully closed, the gravity pull is reduced to zero and the residual tension of the spring is suflicient to hold the door releasably in the closed position.

When the door is opened from its fully closed position, the foregoing events occur in reverse; the spring tension first increasing, then when the roller rides down the front of the cam 28, decreasing to a valley point of tension; and then when the roller no longer engages the cam, again increasing progressively until the door is fully open.

The operation is graphically illustrated in FIGURE 9. The vertical asis represents relative spring tension and the horizontal axis represents the door angle between the fully open and the fully closed position. The valley point of spring tension is denoted as VP. Movement of the door in either direction from the valley point will require the application of force by the consumer.

As pointed out above; door 14, outstop arm 52, supporting arm 22, cam 28, and pivot rod are fixed relative to each other insofar as vertical translational movement is concerned. Therefore, to remove the door and hinge assembly, it is necessary to raise the hooks 24 and 26 vertically (the distance Y of FIGS. 6, 7, and 8) to clear the locating pins and 32 and, therefore, it is necessary to raise the outstop arm 52 vertically an equal distance. The extent of vertical translational movement permitted the outstop arm 52 depends on the distance (distance X of FIGS. 7 and 8) between its top edge and the upper locating pin 30. As shown in FIG. 8, the distance X is greater than the distance Y at the broil position but at no other position of the door (see FIGS. 5, 6, and 7).

Thus at the broil position, the door and hinge assembly is raised vertically until hooks 24 and 26 clear pins 30 and 32. The assembly is then moved horizontally away from the oven. To replace the door, the door and hinge assembly are repositioned by setting the bottom edge of the outstop arm 52 on the lower pin 32 and, while holding the door at an angle more nearly vertical than the broil position, pushing the assembly horizontally inward until the hooks 24 and 26 pass over the pins 30 and 32. The assembly is then moved vertically downward to its original position.

While the door is being removed and replaced there is no change in tension on the spring and no change in the spatial relationship of the door and hinge elements. Therefore, no adjustment of the spring or any of the hinge elements is required during the removal of the door. This latter advantage is secured 'because of the fact that the door and hinge assembly is removed while the spring is at a tension valley point. If, on removal of the door, the hinge would tend to collapse; that is, cause it to act as if closing; this tendency would be offset by the requirement for energy to move the roller56 up the cam 28. If, to the contrary, the hinge would tend to spread; that is, cause it to act as if opening; this tendency would be offset by the requirement for energy to increase tension on the spring. Therefore, the spring tension remains at equi- 6 librium and constant and the spatial relationship of the door and hinge elements remains constant.

Because the manipulation required to attach the door to the range is so simple, because it is unnecessary to attach any springs to the range, and because no screws or other fasteners are needed to attach the door, the whole door assembly, including the hinge mechanism, may be manufactured independently of the main manufacturing assembly line. The door is merely inserted into the range at the end of the assembly line. A stock of such door assemblies may be manufactured prior to the time intended for their use.

Although not illustrated and not necessary to the opera- 4 tion of our invention, we have found it desirable to attach a retaining panel to the hinge panel 44. The retaining panel is fixed relative to the hinge panel 44 and is positioned so that the supporting arm 22 may pass, in its usual circular motion, between the hinge panel 44 and the retaining panel. The space through which the supporting arm 22 passes is no larger than required to allow this motion. The retaining panel thus prevents any possible separation of binge panel 44 from supporting arm 22 and assures that the cam will engage the cam follower when so desired.

It is to be understood that the detailed drawings and specific examples given describe preferred embodiments of our invention and are for purposes of illustration only, that the apparatus of the invention is not limited to the precise details and precise conditions disclosed, and that various changes may be made therein without departing from the spirit of the invention which is defined by the following claims.

We claim:

1. A hinge for the door of an oven for supporting said door as it is opened and closed, and for supporting said door at a broil position intermediate the doors fully open and fully closed position, said oven having structures fixed thereto for engaging elements of said hinge; said hinge comprising:

' (1) pivot means upon which said door pivots as it opens and closes;

(2) a link rnem ber provided with a cam follower, said cam follower being movably secured to said door for circular movement therewith, and for radial movement with respect to said pivot means;

(3) a torsion spring cooperative with said door via said link member, said spring adapted to be under tension at all positions of said door, and said tension acting on said door in a direction toward said doors closed position;

(4) a cam fixed relative to said pivot means being operable when said door is passing through said broil position, and being positioned to engage, when said door is closing, said cam follower at said broil position in a manner to effect radial movement of said calm follower;

(5) an outstop arm extending from and fixed to the inner side of said door and adapted for sliding engagement with said oven structures when the door is being moved from non-lbroil positions, where said structures obstruct the rem-oval of said arm from said oven, to a broil position, Where said arm can be lifted free of said structures; and

(6) supporting means with a fixed position relative to said pivot means and said cam and adapted to removably enga'ge said oven structures;

whereby said door and hinge can be removed from and returned to said oven at only said broil position and when said spring is near a valley point of tension, thus preventing a change in spring tension and a change in spatial relationship between said door, said cam follower, said supporting means, and said cam during such removal and return.

2. The hinge according to claim 1 wherein said support ing means is a sup-porting arm fixed to and extend-ing from said pivot means, said arm being provided with hook elements for engaging said oven structure; whereby the vertical translational movement of said supporting arm and hook elements is limited to the extent of simultaneous vertical translational movement of said pivot means, said door, and said outstop arm' 3. The hinge according to claim 2 wherein the extent of vertical translational movement of said outstop arm permitted by said obstructing structures is, in only said broil position, sufficient to effect the lifting of said hook elements free of said structures.

4. The hinge according to claim 1 wherein said pivot means is a rod and wherein said torsion spring is wrapped around said rod.

5. The hinge according to claim 1 wherein said supporting means, said cam, and said pivot means form a unitary rigid structure.

6. The hinge according to claim 1 wherein said link member comprises a portion which is slidedly engaged in a longitudinal slot in a hinge panel of said door so that engagement of said cam follower with said cam, upon the closing of said door, results in an outward radial movement of said portion in said slot.

7. The hinge according to claim 1 wherein said cam follower is a roller.

8. A hinge for the door of an oven for supporting said door as it is opened and closed; for supporting said door at a :broil position intermediate the doors fully open and fully closed positions; and for cooperation with upper and lower vertically spaced locating pins fixedly secured to said oven; said hinge comprising:

(1) a rod pivotally secured to said door and upon which said door pivots as it is opened and closed;

(2) a torsion spring wrapped around said rod and adapted to be under tension at all positions of said door, said tension acting on said door in a direction toward said doors closed position;

(3) a tension link member secured to said spring;

(4) a roller forming a portion of said link member, said roller being secured to said door for circular movement therewith, for radial movement relative to said pivot rod, and for rotational movement about its own axis;

(5) a supporting arm fixed to and extending from said pivot rod, said supporting arm being provided with spaced hook elements adapted to hook over and rest on said pins, and said supporting arm provided with an upwardly facing cam adapted to engage said roller when said door is in its broil position to effect, as said door is closing, an outward radial movement of said roller and thus to effect a change from decreasing tension to increasing tension on said spring; and

(6) an outstop arm fixed to and extending from the inner side of said door, said outstoparm adapted to move slidingly between said pins as said door is opened and closed, said outstop arm being provided with a hooked end portion adapted to engage one of said locating pins when said door is in its fully open position, said outstop arm being shaped so that the distance between the top edge thereof to the upper pin is, in only said broil position, greater than the distance said supporting arm hooks must be raised in order to lift said hooks clear of said locating pins when said outstop arm is raised upwardly and moved outwardly from said oven;

whereby the engagement of said roller with said cam creates a valley tension point at said broil position; whereby the extent of vertical translational movement of said hook elements is limited to the simultaneous vertical translational movement of said outstop arm; whereby said hinge can be removed from said oven only when the door is in its broil position by raising said door and said outstop arm sufficiently high to permit said supporting arm hooks to be lifted clear of said locating pins and then sliding said outstop arm outwardly from said oven; whereby said door can be returned to said oven by setting said outstop arm on said lower pin and moving, with said door slightly elevated, said outstop arm inwardly between said pins until said supporting arm hook elements hook over said pins; and whereby the tension on said spring and the relative position of said supporting arm, said outstop arm, said cam, and said roller remains substantially constant during such removal and return.

9. The hinge according to claim 8 wherein said tension link member comprises a portion which is slidedly engaged in a longitudinal slot in said door so that engagement of said roller with said cam, upon the closing of said door, results in an outward radial movement of said portion in said slot.

10. A hinge for the door of an oven for supporting said door at a fully open position, at a closed position, at a broil position intermediate the doors. open and closed position, and at intermediate points, said oven having structures fixed thereto for engaging elements of said hinge; said hinge comprising:

(1) pivot means upon which said door pivots as it opens and closes;

(2) a link member provided with a cam follower, said cam follower being movably secured to said door for circular movement therewith and for radial movement with respect to said pivot means;

(3) a cam fixed relative to said pivot means, and, positioned to engage said cam follower at least when the door is adjacent to or at said broil position and being then operable in a manner to effect radial movement of said cam follower;

(4) means for resiliently urging said cam follower in a radial direction opposite the direction effected by said earn;

(5) an outstop arm extending from and fixed to the inner side of said door and adapted for sliding engagement with said oven structure while said door is being moved from non-broil positions, where said oven structures obstruct the removal of said arm from said oven, to a broil position, where said arm can be lifted free of said structures; and

(6) supporting hook means with a fixed position relative to said pivot means and said cam and adapted to removably engage said oven structures;

whereby said door and hinge can be removed from and returned to said oven at only said broil position.

11. The hinge according to claim 10 wherein said cam follower is a roller.

12. A hinge for the door of an oven from supporting said door at the fully open position, at the closed position, at a broil position intermediate the doors fully open and fully closed position and at intermediate positions, said oven having structures fixed thereto for engaging elements of said hinge; said hinge comprising:

(1) pivot means upon which said door pivots as it opens and closes;

(2) a link member provided with a cam follower, said cam follower being movably secured to said door for circular movement therewith, and for radial movement with respect to said pivot means;

(3) a tension spring cooperative with said door and said cam follower via said link member, said spring adapted to be under tension at all Positions of said door, said tension acting on said door in a direction toward said doors closed position and in a direction to urge the cam follower radially relative to said pivot to control resiliently the position of said cam follower;

(4) a cam fixed relative to said pivot means; and being positioned to engage said cam follower at least when the door is moving between the broil position and the closed position, and when the door is in the broil position; and

9 (5) supporting hook means with a fixed position relative to said pivot means and said cam adapted to engage said oven structures; whereby said door may be moved from said open position to said broil position and back and may be moved from said lbroil position to said closed position and back and is held releasably but stably in any of the open, the closed or the lbl'Oil positions.

13. The hinge according to claim 12 wherein said cam follower is a roller.

References Cited UNITED STATES PATENTS 2,539,151 1/1951 Mills 126-194 3,072,117 1/1963 Stoligrosz et a1. 126-191 3,299,879 1/ 1967 Doner 126-194 KENNETH W. SPRAGUE, Primary Examiner.

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