US 3273922 A
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Description (OCR text may contain errors)
p 0, 1966 J. c. RASOR 3,273,922
FURNITURE CONSTRUCTION Filed Sept. 21, 1964 FIG. 1. 7
INVENTOR JOHN C. RAsoR ATTORNEY United States Patent 3,273,922 FURNITURE CONSTRUCTION John C. Rasor, Youngstown, Ohio, assiguor to The General Fireproofing Company, Youngstown, Ohio, a corporation of Ohio Filed Sept. 21, 1964, Ser. No. 397,727 1 Claim. (Cl. 287-54) This invention relates generally to furniture construction and more specifically to a joint connection for rod stock having reinforcing means such as will be particularly suitable for use in the construction of tables, chairs, and other articles of furniture intended to support considerable loads.
The utilization of metal stock of very small diameter for the frame, legs and cross members of furniture articles is becoming increasingly popular in the present day field of furniture construction. Manufacturers are plagued with several problems in connection with their efforts to meet the current public trend towards furniture construction based upon this slender rod-type construction. Heretofore the limits to which the rod stock could be reduced in diameter has been dictated by two factors; namely, the strength and weight of the stock material employed.
For many years aluminum has been one of the principal materials used in the construction of furniture legs, frames and cross members in the metal furniture field in view of its relative inexpensiveness, workability and the almost limitlessness number of finishes which may be applied thereto, particularly by anodizing. However, when aluminum rod stock is used having a diameter of, for example, one half inch in the construction of a chair, it will be realized that there will be an excessive amount of flexing of the framework on the application of even a light load upon the chair and even more importantly, there will be a decided weakness in the joint between the horizontal seat rail of the chair at its juncture with one of the vertically disposed chair legs.
Attempts have been made in the past to eliminate the foregoing problem by merely substituting for the aluminum stock a far stronger material such as steel and although it is true that a much smaller diameter stock may be used when substituting steel for a lighter weight material nevertheless it will be understood that the actual contact area formed within the joint between the two rod members disposed normal to one another is relatively small and in the case of a table or chair for instance, any weight brought to bear upon the horizontal supporting rails of the article will be transmitted to the ends thereof as a shearing force at the joint formed with the vertically disposed leg members.
In order to provide the proper safety factor and to insure against the accidental separation of rod joints as above described, a new and improved joint construction has been devised which may be readily assembled during the manufacture of the present type of furniture aritcles without materially increasing the cost of producing same.
Accordingly, one of the primary objects of the present invention is to provide an improved rod joint particularly adapted for use in furniture construction.
Another object of the present invention is to provide a furniture joint construction particularly adapted to reinforce two rod members disposed normal to one another and to which a substantial shear force is to be applied.
Still another object of the present invention is to provide reinforcing means in a rod joint adapted to increase the shear resistance of the joint.
A further object of the present invention is to provide a joint construction for two rod members disposed normal to one another and including reinforcing means 3,273,922 Patented Sept. 20, 1966 within the joint axially disposed with respect to one of the members together with stiffening means axially disposed with respect to the other of the members.
With these and other objects in view which will more readily appear as the nature of the invention is better understood, the invention consists in the novel construction, combination, and arrangement of parts, hereinafter more fully described, illustrated and claimed.
A preferred and practical embodiment of the invention is shown in the accompanying drawing in which:
FIGURE 1 is a perspective view of an article of furniture illustrating the invention.
FIGURE 2 is an enlarged partial elevation of the furniture construction of FIGURE 1 more clearly showing the invention.
FIGURE 3 is a partial transverse sectional view of the rod joint comprising the invention and taken along the line 3-3 of FIGURE 2.
Similar reference characters designate corresponding parts throughout the several figures of the drawing.
Merely to illustrate one adaptation of the present invention, the subject joint construction is shown as applied to the horizontal rails supporting the seat structure in a chair, generally designated C. In this type of construction a framework formed entirely of cylindrical or tubular rod stock is fabricated to provide the usual four legs 1-4 and horizontally disposed seat rails 5 and 6. The seat S which may be contour molded of any suitable material such as compressed Wood product, glass fibers, etc., is suitably attached to the top of the seat r-ails 5 and 6. Likewise, a similarly constructed back rest 7 is attached by any suitable means to the upper portion of the framework as shown in FIGURE 1.
As most clearly seen in FIGURES 2 and 3, the joint connection between the end of the horizontal seat rails 5 and the outer peripheral surface of the adjacent vertically disposed leg 2 is provided with reinforcing means comprising a steel pin 8 passing substantially all the way through the diameter of the leg 2 and extending approximately an equal distance into the end of the seat rail 5.
Heretofore the joint connection in a construction of this type has comprised merely an abutment between the opposed surfaces of the rail 5 and leg 2, which opposed surfaces were then welded or brazed, an operation which always carried with it a certain degree of security risks in view of the substantial loads to which the completed furniture article may be subjected. It will be understood that it would not be uncommon for well over two hundred pounds to be imposed upon the chair seat S and a better part of this Weight would be transmitted through the seat to the horizontal seat rail 5 which in turn would conduct this force as a shear force to the brazed or welded joint.
In the past this brazed or welded type of connection was the only practical means for accomplishing the desired result inasmuch as the slenderness of the seat rail and chair legs precluded any substantial mechanical method of fastening.
In forming the present joint construction the exposed face of the end of the horizontal seat rail 5 is provided with a concave surface 9, the curvature of which conforms to the opposed mating surface of the outer perimeter of the chair leg 2. A pin receiving opening is provided substantially all of the way through the diameter of the leg 2 for the reception of a steel pin 8. Likewise a similar bore is formed through the center axis of the end of the rail 5. One end 812 of the pin 8 is driven into the opening through the leg 2 whereafter the seat rail 5 is assembled with its bore surrounding the exposed end 8a of the pin 8. Preferably the openings formed in the leg and rail are such that a press fit is accomplished as the parts are assembled. Alternatively, suitable other anchoring means may be employed to insure a rigid and operation the exposed edge of the end of the rail 5 mating with the leg 2 may still be welded or brazed which step now would be primarily for the sake of appearance such as to produce an attractive bead or fillet.
To more readily appreciate the solution offered by the present invention it should be realized that the diameter of the rod stock intended to be used in combination with this invention is of a slenderness which precludes any of the more conventional mechanical fastening methods. For example, it is proposed to utilize horizontal rails on the order of inch diameter in combination with vertical leg members of only slightly larger diameter, such as inch. It will be realized that by using a reinforcing steel pin on the order of inch diameter, as above proposed, a rigid rod-type joint is achieved between two members disposed normal to one another which joint will safely endure without failure the application of several times the intended shear stress for which it is designed in the field of furniture construction.
In view of the usual substantial length or height of the legs 14 of the furniture article it is desirable to attach a vertical stiffener 10 to the side of the legs opposite that to which the seat rail is attached. As will be most clearly seen in FIGURE 3, the stiffener 10 comprises a thin bladed member preferably of a thickness less than the diameter of the pin 8 and axially aligned with respect to the leg 2 and diametrically opposed to the rail 5. The stiffener 10 may be attached to the periphery of the leg by any suitable means such as welding, brazing or with an epoxy-type adhesive in order to provide additional rigidity to the length of the leg members. The stiffener member is particularly desirable whenever the leg members of the furniture article are constructed in a normally inclined relationship, however, their inclusion is recommended even when the leg members are perfectly vertically disposed, inasmuch as in the case of a chair for example, it is quite likely that the occupant may tilt back or sit on the edge thereof and place a tremendous lateral stress upon the leg members which stress will not only be transmitted through the point of the rod joint but also have a tendency to deflect the leg members.
It is to be understood that the invention is not limited to the specific features shown, but that the means of con struction herein disclosed comprise the preferred form of several modes of putting the invention into effect and the invention is therefore plain in any of its forms or modifications within the legitimate and valid scope of the appended claim.
In an article of furniture having a plurality of legs and at least one load supporting rail member joined between said legs, said legs and rail member of solid metal rod construction of a diameter no greater than one-half inch, the improvement comprising, a joint formed between an end of said rail member and one of said legs, said rail member disposed normal to and in abutment with said leg, the end face of said rail concaved to mate with the abutting surface of said leg, said leg and the adjacent end of said rail member provided with aligned bores, said leg bore extending substantially throughout the diameter of said leg, a metal pin having one end disposed transversely through said leg bore and having its other end axially disposed within said rail bore and retained Within said bores by a press fit, and a stiffener comprising a thin flat bladed member longitudinallyattached to the surface of said leg and extending above and below said pin.
References Cited by the Examiner UNITED STATES PATENTS 2,166,941 7/ 1939 Corbin.
3,069,192 12/1962 I-Iankus 2 87 127 3,080,194 3/ 1963 Rowland 297=248 X FOREIGN PATENTS 840,764 1/1939 France.
CARL W. TOMLIN, Primary Examiner.
D. W. AROLA, Assistant Examiner.