US1439945A - Distant control for industrial cranes - Google Patents

Description

Dec. 26, 1922. 1,439,945

R. W. CHANDLER. DISTANT CONTROL FOR INDUSTRIAL CRANES.

Fl LED APR. 29. I921 glwuenio'a (liken WM Patented Dec. 26, 1922.

UNITED STATES ROBERT WILDER CHANDLER, OF STAMFORD, CONNECTICUT.

DISTANT CONTROL FOR INDUSTRIAL CRANES.

Application filed April 29, 1921.

T 0 all whom it may concern."

Be it known that I, ROBERT \VILDER CHANDLER, a citizen of the United States. and a resident of Stamford, in the county of Fairfield and State of Connecticut, have invented certain new and useful Improvements in Distant Controls for Industrial Cranes; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to means for actuating the controller of a portable electric crane, and it consists of suitable actuating means extending from the end of the boom of the crane to the handle of the controller whereby the operator may control the operation of the hoist motor with one hand and shift the boom and guide and steady the load being handled with the other hand.

It further consists in the details of construction and combination of parts as will be more fully explained and pointed out in the claims.

In the accompanying drawings, Figure 1 is a View in plan of a crane embodying my invention; Figure 2 is a similar view of a. modified form and Figure 3 is a view in side elevation of the latter.

5 represents a truck platform mounted on wheels (not shown) and provided with a boom 6 pivoted at 7 to the mast 8. 9 is the hoist chain secured at one end to a drum actuated by a motor 10. This chain passes over the sheave 11 at the top of the mast and over sheave 12 at the free end of the boom, and is provided at its free end with a hook 13 to engage a sling supporting the load to be lifted. The hoist chain is provided with a block 13 adapted to engage the free end of the boom for lifting the same, and the boom carries parallel levers 1-l having projections on their lower edges adapted to engage detents 15 on the mast for hold ing the boom in the position to which it has been raised by the hoist chain, and in any position to which it may be lowered. The motor is controlled by the controller 16 which is actuated by the handle 17.

The parts above described represent one type of industrial crane now in use, which I have usedfor illustrative purposes only, as my invention relates to means for con- Serial No. 465,397.

trolling the motor of the crane, and not to the construction .of the crane.

, In all crane trucks in use, two men are required to operate it, one on the operators platform to control the wertical movements of the crane boom and load on the crane, and the hoist mechanism and the other on the floor to swing the boom to position, and make fast the load and steady it and prevent slipping of the sling etc., and the object of my invention is to provide means so that one man may manipulate the truck and hoist mechanism and after he has moved the truck with or without its load to the point where the load is to betaken up or de posited, leave thedrivers platform and operate the motor through a remote or distant control with one hand, to lower or lift the load, and shift the boom, thereby dispensing with the services of'one man,

and lessening the chances of accident, as the sole operator has absolute control over the mechanism and the load.

The preferred form of my'invention is disclosed in Figure 1 and consists of two control ropes, 18v one at each side of the boom, and both secured at one end to the boom adjacent the free end thereof. These ropes extend rearwardly alongside of the boom and preferably through guides 19 on the latter, and also through guides 20 on the truck plaform or parts carried thereby so as to prevent undue sagging of the ropes,

the inner ends of the ropes passing around sheaves 21 carried by the crane platform or parts thereon and secured at their ends to the controller lever 17 With this arrangement it will be seen that when the controller is in vertical position, a pull on one rope will move it in a direction to actuate the motor to hoist the load, and a pull on the other rope will move the lever back to neutral position and a further pull actuate the motor to lower the load. The

control ropes are s'ufiiciently long so that In the construction shown in Figures 2 A and 3, one of the ropes 18 is connected to a lever 22 rigid with a shaft 23 which passes through the pivot pin of the boom. This shaft is provided at its opposite end with a similarly disposed lever to which the rope 18 is secured at one end. The ropes 18 and 18 are connected at their rear ends to the opposite ends of a bell crank lever 23 pivotally mounted on a bearing 24 carried by the motor, and the third arm of lever 23 is connected by the adjustable rod 25 with the controller lever 17. With this construction, it will be evident that by pulling on one rope 18 or 18, the bell crank lever will be turned to shift the controller lever in a direction to hoist or lower a load, and by pulling on the other rope the lever 17 will be returned to neutral position, and a further pull on the same rope will shift the controller lever to a position to lower or hoist the load as the case may be.

In the operation of the crane the operator 1 rides on the platform of the truck while driving the truck from point to point. When he reaches the point where he is to lift or lower a load, he leaves the platform and operates the controller, through the controlropes, and at the same time turns the boom, if necessary, and steadies the load, the whole operation of lifting, lowering and stopping the hoist mo tor, and manipulating the load being under the control of the single operator;

It is evident that many slight changes might be resorted to in the relative arrangement of parts shown and described without departing from the spirit and scope of my invention hence I would have it understood that I do not wish to confine myself to the exact construction and arrangement of parts shown and described, but

Having fully described my invention what I'claim as'new and desire to secure by Letters-Patent, is

1. Ina crane, the combination of a boom, hoisting means, a drum for said hoisting means, an electric motor for actuating the drum, a controller for the motor, and flexible means attached to the boom adjacent the free end of the latter and connected with the controller lever, whereby an operator on the floor manipulating the load, may actuate the flexible means to start and stop the motor.

2. In a crane, the combination of a boom, a hoist chain or cable, a drum, an electric motor for actuating the drum, a controller, two ropes secured at their outer ends to the boom, and connected at their inners ends to the controller lever, and guides for the ropes, the said ropes being in position to be manipulated by an operator on the floor adjacent to the load to be handled.

In testimony whereof, I have signed this specification in the presence of two subscribing witnesses.

1 It. WILDER CHANDLER.

Witnesses:

BLANCHE WOLFSON, CHARLES A. BERRY.

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