US2736526A - Lifting device for lifting heavy objects - Google Patents

Description

1956 R. A. FORBES LIFTING DEVICE FOR LIFTING HEAVY OBJECTS Filed June 2, 1952 R. J]. FZJrbes INVENTOR ATTORNEYS ited States Patent Ofilice 2,736,526 Patented Feb. 28, 1956 LIFTING DEVICE FOR LIFTING HEAVY OBJECTS Robert A. Forbes, Monroe, Mich.

Application June 2, 1952, Serial No. 291,135

1 Claim. (Cl. 248-125) This invention relates to a device designed for lifting heavy objects, and is especially effective in lifting steel bars and placing them on saw tables of steel cribs.

An important object of the invention is to provide a lifting device which may be readily moved with its load to a location wherein the load is to be deposited, the device operating by alternately raising and lowering one end of the load, elevating the load to a position where it may be easily transferred onto the saw table to be cut to the desired length.

A still further object of the invention is to provide a lifting device wherein the bar being lifted provides the lever by means of which the supports are moved vertically to elevate the load.

With the foregoing and other objects in view which will appear as the description proceeds, the invention consists of certain novel details of construction and combinations of parts hereinafter more fully described and pointed out in the claim, it being understood that changes may be made in the construction and arrangement of parts without departing from the spirit of the invention as claimed.

Referring to the drawing:

Figure 1 is a rear elevational view of a lifting device constructed in accordance with the invention.

Fig. 2 is a side elevational view thereof.

Fig. 3 is a sectional view taken on line 3-3 of Fig. 1.

Fig. 4 is a sectional view taken on line 44 of Fig. 3.

Referring to the drawing in detail, the reference character 5 designates the base of the lifting device, which is supported by the casters 6.

Rising from the base 5 is the inverted U-shaped upright 7, including the legs 7 the upper ends thereof being connected by the curved section 8.

Formed along the rear surfaces of the legs 7 are teeth 9 extending throughout the length of the upright 7, which teeth cooperate with the pawls 10 that are pivotally mounted on the movable supports 11, the pawls having openings so that they may be fitted over the legs 7, as clearly shown by Fig. 3 of the drawing, the openings of the pawls being such that the pins 12 of the pawls may contact with the teeth 9 in such a way and at such an angle with respect to the supports, that a binding action is set up between the supports and legs 7 to hold the supports against movement longitudinally of the upright 7. The supports 11 are formed with openings so that the supports may be fitted over the legs 7' of the U-shaped support for sliding movement.

Extending from the pawls 10 are pins 13 formed with hooks 14 at their outer ends over which one end of the coiled spring 15 associated therewith is positioned, the opposite end of the coiled spring being positioned over the hooked end 16 of the arm 17, the springs 15 of the vented under normal conditions.

The supports 11 are connected by means of the table 18, which table has pivotal connection with the supports 11, by means of the bearings 19 that extend from the table and which have openings to receive the pivot pin 20.

Chains 20 are secured to the table 18 and are designed to fit over the load being lifted, which in the present showing is in the form of a steel bar 21.

In order to brace the upright 7 against tilting forwardly under the weight of the load, the brace bars 22 are provided and have their lower ends secured to the base 5, while the upper ends thereof are welded to the legs of the U-shaped upright 7, as clearly shown by Fig. 2 of the drawing.

It might be further stated that in order to prevent turning of the supports 11 on the legs 7, the legs 7 are square in cross section and fit within square openings of the supports 11.

In operation a heavy bar to be lifted is secured to the table 18 in true balance thereon and the chains tightened over the steel bar 21 securely fastening the bar in balance on the table and supports.

One end of the bar is now elevated raising the support connected with the elevated end of the bar. A downward pull is now directed to the elevated end of the bar which causes the opposite support to be raised to a position in a plane with the support first elevated. This operation is duplicated until the supports are moved to the desired elevated position with a step-by-step motion, whereupon the chains are released and the metal bar transferred to the saw table for further treatment to condition the bar for a particular use.

The supports may be lowered by merely moving the pawls 10 to positions out of contact with the teeth 9 of the U-shaped uprights, to gravitate to the lower ends of the uprights or a position to receive another bar to be lifted.

Having thus described the invention, what is claimed is:

In a device of the character described, a wheeled base, an inverted U-shaped vertical upright mounted thereon, in spaced relation with one end of the base embodying legs teeth formed along one longitudinal edge of each leg of said upright, brace bars extending from the bight of said upright to said base, a supporting bracket carried by each leg, each bracket having a bore therein surrounding its associated leg, an extension on each bracket extending rearwardly of its associated leg, a V-shaped aperture in each bracket, a pawl pivotally mounted in each aperture, a pin carried by each pawl engageable in a selected tooth, a spring connection between each extension and the free end of its associated pawl, and a load supporting table pivotally mounted between and across said supporting brackets.

References Cited in the file of this patent UNITED STATES PATENTS 191,579 Frost June 5, 1877 365,748 Jacoby June 28, 1887 588,253 Wagner Aug. 17, 1897 621,856 Schwarz Mar. 28, 1899 1,656,150 Little Jan. 10, 1928 2,063,661 Curran Dec. 8, 1936 2,316,892 Saul Apr. 20, 1943 2,365,410 Holmes Dec. 19, 1944

Images