US2861625A

US2861625A - Folding chair

Info

Publication number: US2861625A
Application number: US570769A
Authority: US
Inventors: Frederick E Walton
Original assignee: RUSH STAMPING Co
Current assignee: RUSH STAMPING Co
Priority date: 1956-03-12
Filing date: 1956-03-12
Publication date: 1958-11-25
Anticipated expiration: 1975-11-25

Description

Nov. 25, 1958 F, E, WALTON 2,861,625

FOLDING CHAIB- Filed March 12, 1956 INVENTOR.

Freder/ck E War/(0n Affomey United States Patent FOLDING CHAIR Frederick E. Walton, Owosso, Mich., assignor to The Rush Stamping Company, Toledo, Ohio, a corporation of Ohio Application March 12, 1956, Serial No. 570,769

3 Claims.- 7 (Cl. 155-142) This invention relates to the construction of folding chairs, and particularly to a type in which front and rear leg'systems are each pivotally connected to a seat on axes of rotation which remain fixed with respect to the seat. In the erected position of the chair, the upper end of the rear leg enters into a solid' abutting relationship with the front leg, and a rigid triangular structure results which includes (11) the portion of the seat between the pivot connections to the front and rear legs, (b) the portion of the front leg structure between the seat and the point of. engagement of the rear leg, and (c) the portion of the'rear leg between the pivot connection tov the seatand its point of conjunction with the front leg. In this relationship, the load applied to the forward portion of" the seat serves to force the upper portion of the rear leg more securely into solid engagement with the front leg, and the chair remains stable under'all normal conditions of use regardless. of theposition of the applied load. When load is applied to the rear portion of the seat, it passes to a greater extent directly through the rear leg, and the particular proportions of the chair will have a considerable effect on the distributions of the loading. Regardless of these proportions, however, this type of chair has proven to be one of the most stable types of folding chair structure, providing that an arrangement is included in the structure for limiting the tendency of the upper portion of the rear legto slide along the front leg when load is applied to the chair. The problem of positioning the upperend of the. rear leg with respect to the front leg is complicated by the fact that the folding movement of the chain involves a movement of the upper part of the rear leg in a downward direction (with respect to the normal attitude of the chair) away from its point of v engagement with the front leg in the erected condition.

Several different arrangements have been provided by previous inventors. for accommodating the relative movement of'the front leg and rear leg in this type of a folding chair mechanism while maintaining the relative position of the legs in the erected condition. The patent to Burnham, No. 2,568,269,,illustrates the use, of an auxiliary linkage pivoted at one end to the front leg and at its opposite end to the rear leg for accommodating this movement, and the Patents Nos. 1,789,295 and 2,596,424 show an arrangement'for maintaining the engagement of the upper portion of the rear leg with the front leg and involving the movement of. an extension of the rear leg within. a slotin the front leg to accommodate the folding movementof' the chair.

This invention provides for the folding movement of the rear leg with respect to the front by the use of a telescoping coupling member preferably mounted within a hollow rear leg structure, the upper end of the telescoping member remaining in engagement with the front leg at one point, and establishing what amounts to a pivotal connection with the front leg at that point. During the folding movement of the chair, the upper portion of the rear leg moves away from the front leg, leaving the 2,861,625 Patented Nov. 25, 1953 The several features of the invention will be discussed in detail through an analysis of the particular embodiments illustrated in the accompanying drawing. In the drawing: Figure 1 presents a perspective elevation of a chair embodying this'invention, with the chair in the erected condition.

Figure 2 is an enlarged view of a fragmentary portion of the chair in the folded position.

Figure 3 is a fragmentary exterior side elevation on an enlarged scale, and showing the relationship between the front and rear legs and the seat, with the chair in the erected condition.

Figure 4 shows a sectional side elevation on an enlarged scale, showing. the interior of the principal components of the chair when in the erected condition.

Figure 5 is a section taken from the plane 55 of Figure 2.

Figure 6 is a section taken on the plane 6-6 of Figure 2.

Referring to the drawing, a folding chair is illustrated which includes the seat 10, the back Til, the front leg system 12 including the. legs E20 and 1212 connected by the cross-tie 13, and the rear leg system 14 including the legs 14a and Mb. connected by the cross-tie 15. The front leg. system 12 is pivotally connected to the seat 10 as indicated at its on an axis which is at an intermediate position on the seat proceeding from front to rear. The rear leg system is pivotallyconnected to the seat as shown at 17 at a point to the rear of the connection 16. The back 11 of the chair may be considered as fixed with respect to the front leg system 312 as a result of being secured to continuationsof the member forming the legs 132a and 12b. Preferably, the legs and the section to which theback if is secured is formed as shown out of onecontinuous piece.

Preferably, all of the legs are of tubular steel construction formed to the illustrated cross section from fiat strips stock, and are provided with the rubber feet 18 through 21, inclusive, to avoid marring a floor surface on which the chair rests.

The abutting surface 22 at the uppermost portion of the rear leg is in solid engagement with the rear surface 213 of the, front leg when the chair is in the erected condition, as shownin Figures 1, 3, and 4. Folding movement from the position shown in Figure 4 to that shown in Figure 2 involves the movement of the abutting surface 22 away from its position of contact with the front leg, and. some arrangement must he provided to not only maintainthe upperportion of the front leg against a tendency toslide along the rear face of the front leg (in the erected condition), but also to guide the rear leg into the, proper position as the chair is erected. To provide this action, a telescoping member 24 is slideably mounted Within the tubular rear leg in the illustrated preferred form of the invention. The telescoping member has a hook portion 25 which engages a slot 26 in the rear face of the front leg, with the laterally-extending flanges 27 and 28 (refer to Figure 5) preventing withdrawal of the hook-shaped portion 25 from engagement with the front leg. The front leg is preferably formed of sheet material stamped or rolled into the illustrated cross sectional configuration, with the seam being disposed along the center of the rear surface 23. The hook portion may be assembled to the front leg with the flanges 27 and 28 inside the hollow front leg either prior to the time of finally closing the front leg cross section, or by prying it open a sufficient amount to admit the flanges 27 and 28. Alternatively, the two sections of the telescoping member to which the flanges 27 and 28 are respectively secured may be engaged individually with the slot 26 before inserting them within the rear leg.

The (normally) lower portion of the telescoping member 24 is provided with a slot 29 which embraces the shaft 30 providing the pivotal connection between the seat and the rear leg system. In the illustrated modification of the invention, the shaft 30 is notched as shown at 31 (refer to Figure 6) within the interior of the hollow rear leg where it is engaged by the telescoping member 24. This member is therefore laterally positioned by the combined effect of the sides of the slot 31 and a tendency to ecntralize itself within the arcuate portion 32 of the rear leg cross section. The shaft 30 is headed over or riveted as shown at 33 on the outside of the rear legs to maintain the assembled relationship of the components. On the assembly of the shaft 30 to the position shown in the drawings (preceded by the assembly of the portion 25, as discussed above), the assembled relationship of the legs, seat, and coupling members is permanently established.

It is preferred that the front legs be reinforced by the channel-shaped member 34 which extends on either side of the shaft 35 establishing the pivotal connection shown at 16 in Figure 1.

The particular embodiments of the present invention which have been illustrated and discussed herein are for illustrative purposes only and are not to be considered as a limitation upon the scope of the appended claims. In these claims, it is my intent to claim the entire invention disclosed herein, except as I am limited by the prior art.

I claim:

1. A folding chair, comprising: a seat; tubular front leg means having opposite slots in the rear face thereof normally above said seat and pivotally connected to the sides of said seat, respectively, at an intermediate position from front to rear; a back fixed with respect to said front leg means; tubular rear leg means, said rear leg means having a bearing surface adjacent the normally uppermost end thereof formed to conform to the rear surface of said front leg means with said chair in the erected condition; shaft means extending laterally with respect to said seat on an axis to the rear with respect to said seat of the pivotal connection of the said front leg means thereto, said shaft means traversing the width of said seat and also traversing said rear leg means, and said shaft having a notch in the side thereof adjacent a side of and Within said leg means, respectively; and a coupling member slideably mounted with respect to each of said rear leg means, respectively, for movement parallel to the axis of said rear leg means, said coupling member being disposed within said rear leg means, and having a hook-shaped end projecting beyond the said bearing surface, and having a slot engaging said notch, said hookshaped end normally engaging said slot in the rear face of said front leg means, and having flange means preventing the withdrawal thereof from said slot, said coupling 4 member having a length suflicient to remain in engagement with said rear leg means throughout the movement of said chair from erect to folded condition.

2. A folding chair, comprising: a seat; tubular front leg means having opposite slots in the rear face thereof normally above said seat and pivotally connected to the sides of said seat, respectively, at an intermediate position from front to rear; tubular rear leg means, said rear leg means having a bearing surface adjacent the normally uppermost end thereof formed to engage the rear surface of saidfront leg means with said chair in the erected condition; shaft means extending laterally with respect to said seat on an axis to the rear with respect to said seat of the pivotal connection of the said front leg means thereto, said shaft means traversing the width of said seat and also traversing said rear leg means; and a coupling member including a pair of similarly formed sections each slideably mounted with respect to said rear leg means, respectively, for movement parallel to the axis of said rear leg means, said coupling member being disposed within said rear leg means, and each of said sections having a hook-shaped end projecting beyond the said bearing surface, and having a slot engaging said shaft, said hook-shaped ends normally engaging said slot "n the rear face of said front leg means, and each of said coupling member sections having flange means preventing the withdrawal thereof from said slot, said flange means on one of said sections extending in the opposite direction from said flange means on the other of said sections, said coupling member having a length sufficient to remain in engagement with said rear leg means throughout the movement of said chair from erect to folded condition.

3. A folding chair, comprising: a seat; tubular front leg means having opposite slots in the rear face thereof normally above said seat and pivotally connected to the sides of said seat, respectively, at an intermediate position from front to rear; tubular rear leg means, said rear leg means having a bearing surface adjacent the normally uppermost end thereof formed to engage the rear surface of said front leg means with said chair in the erected condition; shaft means extending laterally with respect to said seat on an axis to the rear with respect to said seat of the pivotal connection of the said front leg means thereto, said shaft means traversing the width of said seat and also traversing said rear leg means; and a coupling member slideably mounted with respect to each of said rear leg means, respectively, for movement parallel to the axis of said rear leg means, said coupling member being disposed within said rear leg means, and having a hook-shaped end projecting beyond the said bearing surface, and having a slot engaging said shaft, said hook-shaped end normally engaging said slot in the rear face of said front leg means, and having flange means preventing the withdrawal thereof from said slot, said coupling member having a length sufficient to remain in engagement with said rear leg means throughout the movement of said chair from erect to folded condition.

References Cited in the file of this patent UNITED STATES PATENTS 2,555,113 Burnham May 29, 1951 2,568,269 Burnham et al. Sept. 18, 1951 2,596,424 Morse May 13, 1952 2,757,715 Hendrickson Aug. 7, 1956