US2031549A - Crane - Google Patents

Description

S. W. RUFF Feb, 18, 1936.

CRANE Filed Feb. 14, 1955 2 sheets-sheet 1 S. W. RUFF Feb. 18,1936

CRANE Filed Feb. 14, 1955 2 Sheets-Sheet 2 567M008 W fiz/FF Patented Feb. 18, 1936 UNITED STATES PATENT OFF-ICE CRANE Seymour W. Ruff, Baltimore, Md. Application February 14, 1935", Serial No. 6,563

6 Claims.

The invention relates to cranes and more particularly it has reference to the provision of a crane whose main boom carries an extension boom.

Primarily the invention has for its object to provide a crane which can make long reaches and lift very heavy loads. Further, it is an object of the invention to provide a specially designed crane for the purposes of raising and setting stone, steel and other building materials on high buildings and in remote places that cannot be reached in an economical fashion by any other crane now known; the object is fulfilled by the use of special braces, bridge structures, reinforcements and attachments so that an auxil iary boom may be attached at a place remote from each end of the main boom.

Further, it is an object of the invention to provide a crane with an extension boom that is mounted on the main boom so as to operate in a vertical plane through approximately 150-160 degrees.

A further object is to provide a crane possessing the advantageous characteristics above mentioned, with as light a main boom structure as is possible and yet have the structure strong enough to prevent buckling, bending or twisting while a load is being handled.

Other objects will in part be obvious and in part be pointed out hereinafter.

To the attainment of the aforesaid objects and ends the invention still further resides in the novel details of construction, combination and arrangement of parts, all of which will be first fully described in the following detailed description, and then be particularly pointed out in the appended claims, reference being had to the accompanying drawings, in which:-

Figure 1 is a side elevaiton of the invention, the high and low positions of the auxiliary or extension boom being shown in dotted lines.

Figure 2 is an enlarged detail horizontal section on the line 2--2, of Figure 1.

Figure 3 is an enlarged detail plan view of the lower end of the main boom.

Figure 4 is an enlarged detail plan view of the upper end of the main boom.

Figure 5 is a detail plan view of the auxiliary or extension boom.

Figure 6 is a side elevation of the parts shown in Figure 3.

In the drawings, in which like numerals and letters of reference indicate like parts in all the figures, l represents a tractor of the wellknown Caterpillar type which includes a body comprising a base 3 and a ballast box 2. The construction of the tractor is of a well-known type and per se is not of the present invention. 8 designates the main boom which is composed of a skeleton structure consisting of longitudinal corner irons 9, zigzag bracing or diagonal bracing bars I0 and transverse or crossed braces H. The boom is also further braced by lower reinforcing plates I2, upper reinforcing plates l3 and intermediate reinforcing plates 14 and IS. The main boom is pivoted at 4 to the base 3 to swing in a vertical plane. In order to limit the upward movement of the main boom to a vertical position it is provided with a bumper, or bumpers, l6 notched at I! to engage a cross bar I which is rigidly mounted on the tractor by means of inverted V-fra'ines consisting of front and rear braces 5 and 6 respectively. 7

Located about two-thirds of the way up the main boom, where the intermediate reinforcing plates 14 are provided, is a bridge member l8 that is secured to the boom and projects rearwardly transversely thereof, there being hog rods I9 provided for rigidly connecting the bridge with the respective ends of the main boom. In order that these rods may be placed under tension they are made in sections united by turn-buckles 20. The main boom 8 is swung on its pivot by means of a mainboom cable 2| which is anchored at the cross bar or rod 1, passes over a pulley 23 at the free end of the main boom and has its end connected with the main boom cable drum 22 that is. mounted on the base of the tractor. At the upper orfree end of the main boom isprovided a guide 24 for the various cables which pass that point.

The extension boom which constitutes an essential part of the present invention is indicated at 25 and consists preferably of side bars 26 and spacer blocks 21, there being bearing'plates 28 provided at one end'of the'auxiliaryboom to carry the hinge ears through which the hinge pin 30 passes, the pin 30 also passing through ears on the hinge members 29 that are secured to the main boom in line with the bridge [8 but on the opposite side thereto. The extension boom cable 3| is anchored at 36 to the extension boom and passes over a series of pulleys 32, 34, 23, 33, and 39 from whence it passes to the extension boom cable drum that is mounted on the base 3.

The load cable is anchored at 40 to the free end of the auxiliary boom, passes around the load hook pulley block 42 and over the pu1leys'38 and 39 to the load cable drum 4| which is'also mounted on the base 3.

As shown in Figure 1, when the main boom is in substantially a vertical position the auxiliary boom may be swung through an arc of approximately degrees. In this way it can be used as a longitudinal extension of the main boom, or as a lateral extension of the main boom for the purpose of reaching over high obstructions to pick up or let down a load beyond the obstruction, making the crane especially adapted to the placing or removing of a load over a high wall or where the crane cannot be gotten into the location where the load is to be placed or removed. By manipulating both the main and the auxiliary booms an almost unlimited number of positions within range of the booms for the load carrying hook to reach can be obtained without the necessity of moving the tractor from a given position.

With a crane constructed according to the present invention, should the load cable part or the load break loose while lifting a heavy load, the structure is such as to resist a flap back and a tendency of the boom to double up, thereby avoiding a great danger present in cranes used prior to this invention. Experience has shown that with a crane having a standard main boom 2. sixty foot extension boom can readily be used; in fact in experiments a seventy-three foot boom has been found practicable.

From the foregoing description, taken in connection with the accompanying drawings it is though that the complete construction, operation and advantages of the invention will be clear to those skilled in the art.

What I claim is:

1. In apparatus of the character described, a base, a main boom hingedly mounted at its lower extremity to said base, a bridge secured to said main, boom, hog rods anchored to said bridge and to the respective ends of said main boom, said bridge extending transversely from the main boom rearwardly, an auxiliary boom hingedly mounted on said main boom at the front thereof and adjacent said bridge, a main boom elevating and lowering cable and a drum therefor carried by said base, an extension boom lowering and raising cable and a drum therefor carried by said base, a load cable carried by said booms and a drum therefor carried by said base.

2. In apparatus of the character described, a base, a main boom hingedly mounted at its lower extremity to said base, a bridge secured to said main boom and located at approximately twothirds of the length of the boom from the base, hog rods anchored to said bridge and to the respective ends of said main boom, said bridge extending transversely from the main boom rearwardly, an auxiliary boom hingedly mounted on said main boom at the front thereof and adjacent said bridge, a main boom elevating and lowering cable and a drum therefor carried by said base, an extension boom lowering and raising cable and a drum therefor carried by said base, a load cable carried by said booms and a drum therefor carried by said base.

3. In apparatus of the character described, a base, a main boom hingedly mounted at its lower extremity to said base, a bridge secured to said main boom and located at approximately twothirds of the length of the boom from the base, hog rods anchored to said bridge and to the respective ends of said main boom, said bridge extending transversely from the main boom rearwardly, an auxiliary boom hingedly mounted on said main boom at the front'thereofand adjacent said bridge, a main boom elevating and lowering cable and a drum therefor carried'by said base, an extension boom lowering and raising cable and a drum therefor carried by said base, a load cable carried by said booms, a drum therefor carried by said base, and means to place said hog rods under tension.

4. In cranes, a base having a counterbalance box, a main boom cable drum, an extension boom cable drum and a load cable drum, said drums being carried by said base, a main boom pivoted on a horizontal axis to said base, a main boom cable connected to the free end of said main boom and with said main boom cable drum, said main boom comprising a skeleton steel structure consisting of corner longitudinals reinforced by vertical zigzag braces and transverse crossed braces, reinforcing plates adjacent the ends of said main boom and at intervals in its length, a bridge secured to said main boom intermediate its ends and projecting transversely to the rear thereof, an auxiliary boom pivoted to said main boom in front thereof and adjacent said bridge, hog rods connecting said bridge with the ends of said main boom, an auxiliary boom cable one end of which is anchored to said auxiliary boom and the other end of which is connected to said auxiliary boom cable drum, pulleys on said booms around which said auxiliary boom cable is passed, a work cable one end of which is anchored to said auxiliary boom and the other end of which is connected with said work cable drum, and pulleys on said booms over which said work cable is passed. I

5. In cranes, a base having a counterbalance box, a main boom cable drum, an extension boom cable drum and a load cable drum, said drums 5 being carried by said base, a main boom pivoted on a horizontal axis to said base, a main boom cable connected to the free end of said main boom and with said main boom cable drum, said main boom comprising a skeleton steel structure consisting of corner longitudinals reinforced by vertical zigzag braces and transverse crossed braces, reinforcing plates adjacent the ends of said main boom and atintervals in its length, a bridge secured to said main boom intermediate its ends and projecting transversely to the rear thereof, an auxiliary boom pivoted to said main boom in front thereof and adjacent said bridge, hog rods connecting said bridge with the ends of said main boom, an auxiliary boom cable one end of which is'anchored to said auxiliary boom and the other end of which is connected to said auxiliary boom cable drum, pulleys on said booms around which said auxiliary boom cable is passed, a work cable one end of which is anchored to said auxiliary boom and the other end of which is connected with said work cable drum, pulleys on said booms over which said work cable is passed, and a guide on the end of said main boom for said cables.

6. In cranes, a body, a main boom pivotally mounted on said body for movement in a vertical plane, a bridge projecting transversely from said main boom and located intermediate the ends thereof, hog rods connecting said bridge with the respective ends of said main boom, an auxiliary boom pivoted to said main boom adjacent said bridge and projecting oppositely thereto, main and auxiliary boom cables and drums for operating said booms, and a work cable and drum cooperating with said booms, said auxiliary boom being movable in a vertical plane through an arc of approximately 160 degrees. SEYMOUR W. RUFF.

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