US2778595A - Step ladder scaffold bracket - Google Patents

Description

Jan. 22, 1957 J- W. MASTIN STEP LADDER SCAFFOLD BRACKET Filed July 6, 1953 United States Patent STEP LADDER SCA-FF OLD BRACKET James W. Mastin, Council Blulfs, Iowa Application July 6, 1953, Serial N0. 366,142 1' Claim. Cl. 248-238) I The present invention has for its object to provide a sturdy, safe and easily adjusted device for supporting a workmens scaffold, and which is capable of adjustment of the whole device vertically upon the ladder, i. e., from one step or rung to another step or rung.

A further object is the provision of a device wherein the weight carried by the scaffold is born, not by any insecure attaching device, but by the steps of the ladder.

A further object is the provision of a device which is capable of further refinements in vertical adjustment after the initial attachment of the device to the ladder has been effected.

A further object is to provide for horizontal expansion of the scaffold supporting portion of the device, thus allowing for its use on different widths of ladders, and also allowing for its detachment and readjustment at different vertical levels.

A further object is to provide a locking device for providing maximum safety.

Other and further objects and advantages of the present invention will be apparent from the following detailed description, drawings and claim, the scope of the invention not being limited to the drawings themselves as the drawings are only for the purpose of illustrating a way in which the principles of this invention can be applied.

Other embodiments of the invention utilizing the same or equivalent principles may be used and structural changes may be made as desired by those skilled in the art Without departing from the present invention and the purview of the appended claim.

In the drawings:

Figure 1 is a side view of a pair of ladders in position for supporting a workmens scaffold. This view is partly in cross section.

Figure 2 is a cross sectional view taken on the line 22 of Figure 1.

As used herein, the term step ladder will be understood to include ladders with either flat steps of rungs.

A and A are a pair of ladders oppositely placed and in position to receive and support a workmens scafiold, plank, or platform, shown by the numeral 24. Each ladder is shown carrying the device of the present invention. Its attachment to one ladder only will be described, it being of course understood that a duplicate device and duplicate operations are necessary to provide support for the opposite end of the scaffold. In the drawing the various parts of the duplicate bracket formation which is applied to and held upon the second ladder A are designated by the same numerals as the corresponding parts of the bracket formation which is to be fully described, except that the prime mark is used with each numeral.

10 and 12, 14 and 16 are the flanges respectively of angle members 4 and 5. These angle members 4 and are applied and held to the lges of the ladder in the following manner: an angle strap 18 is riveted to or otherwise fastened upon the flange 12 of the angle member 4,

' ends thereof. These tabs 24 and 26 fall on oppositesides. of the ladder style B or B, and hold the angle members.

2,778,595 Patented Jan. 22,

the strip 1-8 and the curved strap shown at 20 are provided with a sliding screw and slot connection 22, and form adjustable gripping means for securely attaching the angle members one to each of the legs of the ladder. It will be noted that downward thrust, such as would occur when weight is applied to the scaffold, causes tighter gripping of the ladder leg by the curved strap 20.

An angle tab 24 is riveted or otherwise held to the flange 10 at or near its lower end, and the tab 26 is riveted or otherwise held to the flange 12 midway between the against lateral or swinging movement.

Angle members 4 and 5 "are provided at intervals throughout their lengths with means for engaging and holding in locked position a telescoping device hereinafter to be described, which is adapted to and designed for the purpose of receiving and supporting a scaifold, plank or platform. This means for receiving and holding the scaffold supporting arm is shown as a series of key hole slots 42 and 43, and lugs 44, positioned near the rounded end of each of the slots.

A rod 28 carries a radially protruding pin or lug 40, and is engaged immovably by a pin 36 and held Within a fitting cylinder 32 so that the end carrying the pin protrudes from the end of the cylinder 32 far enough so that it can be received in any one of the key hole slots 42 and 43 of the slot receiving the pin 40. Upon rotation of the members 32 and 28 the pin 40 will engage the lug 44 and come to a stop. The rod 30, cylinder 34, pin 38, pin 46 and stop lug 48 form a similar device for attachment and locking to angle member 4 which it itself secured to the other style or leg, unshown, of ladder A.

The relative lengths of the rods 28 and 30 and of the receiving cylindrical members 32 and 34 are of prime importance. Whereas the rod 28 is much shorter than its receiving cylindrical member 32, the rod 30 is much longer and protrudes from the end of the receiving cylinder 34. The projecting end of the rod 30 is slidably received within the cylindrical member 32.

In operation, after the two angle members 4 and 5 have been applied as shown to the two uprights of a ladder, cylindrical members 32 and 43 are grasped with either hand and slid toward one another until the rods 28 and 30 have reached a position where contact can be made with a pair of key hole slots as shown at 42 and 42'. Upon rotation, the pins 40 and 46 contact portions 43 and 45 of the corresponding key hole slots, rods 28 and 30, then slip through said key hole slots, and upon further rotation locking is accomplished by contact of the pin 40 with the lug 44 and the pin 46 with lug 48.

From the foregoing description it is thought to be obvious that a step ladder scaffold bracket constructed in accordance with my invention is particularly Well adapted for use, by reason of the convenience and facility with which it may be assembled and operated, and it will also be obvious that my invention is susceptible of some change and modification without departing from the principles and spirit thereof, and for this reason I do not wish to be understood as limiting myself to the precise arrangement and formation of the several parts herein shown in carrying out my invention in practice, except as claimed.

I claim:

A bracket for attachment to a ladder comprising: two elongated side members adapted to extend longitudinally of the upright side styles of said ladder, a transverse cross bar attached at its ends to said side members and adapted to receive a scaffold thereon, transverse gripping straps extending transversely of said elongated side members respectively and extending outwardly from the normally underside of each of said side members and attached thereto respectively at the normally upper ends of said side members and having hooked outer ends for gripping around the opposite side of said ladder upright styles respectively, said transverse gripping straps being adapted to be disposed extending transversely across the top of a rung of said ladder whereby the pressure of said scaffold downwardly against said bracket will be borne at least in part by the said rung of said ladder, said elongated side members being adapted to be disposed with their normally lower ends resting upon the respective ladder upright styles whereby a portion of the pressure of the scaffold upon said bracket is carried by the ladder upright styles, and each side member having attached thereto at least two style engaging tabs projecting outwardly from said side members respectively on the underside thereof and at the normally lower ends thereof, the said style engaging ears of each bracket side member being spaced apart for receiving therebetween in close proximity the opposite sides of the respective ladder upright styles so as to prevent said side members from moving transversely of said ladder styles.

References Cited in the file of this patent UNITED STATES PATENTS 1,143,678 Winans June 22, 1915 1,144,072 Sherwood June 22, 1915 1,658,753 Wirth Feb. 7, 1928 1,960,863 Boyer May 29, 1934 2,140,828 Carle Dec. 20, 1938 2,675,982 Budy Sept. 11, 1951 2,680,554 Dakin June 8, 1954

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