US 4,275,797 AGranted

Scaffolding power attachment

OwnerRaymond R. Johnsoninventor

Life of this patent

Estimating the term…

Loading patent…

Abstract

A power unit for attachment to scaffolding towers such as commonly used for overhead work in the installation of wiring, ductwork, painting, and finishing. A single power unit attached to one leg of a scaffolding tower can move, about the worksite, a large scaffolding tower assembly comprised of one or more individual scaffolding towers. Two power units working in tandem on separate legs of the scaffolding tower assemblage, provides increased maneuverability. Each power unit has separate motors to drive and to change the direction of a scaffolding tower assembly. One electric motor pivots the power unit about the scaffolding tower leg to which it is attached, thereby changing the direction of motion of the scaffolding tower assembly. Another electric motor of the power unit provides power to a drive wheel of the power unit, and consequently moves the scaffolding tower assembly. A brake prevents rotation of the drive wheel when the power unit is not in operation, thereby keeping the scaffolding tower assembly in one location. A clutch within the drive wheel mounting allows the scaffolding to be manually freewheeled about without interference from the scaffolding power unit. A power cord and an electrical control cable with a control console may be extended to any length for remote control of the scaffolding power unit and when not in use may be coiled within the unit for convenient storage.

Claims7

Dependent claims

A scaffolding power unit for attachment to scaffolding tower assemblages of the type commonly used for overhead finishing work in the installation of wiring, lighting fixtures, duct work and ceilings, which have detachable caster wheels so they may be rolled from place to place, the scaffolding unit comprising:

(a) a main frame;
(b) a pivotal attachment means connected to the main frame which pivotally attaches the scaffolding power unit to a single leg of the scaffolding tower assemblage;
(c) a drive wheel, rotatably attached to the main frame;
(d) a propelling means connected to the drive wheel which provides for linear motion of the scaffolding power unit and the attached scaffolding tower assemblage;
and
(e) a clutch means, such that the propelling means may be disengaged from the drive wheel to rotate freely so the scaffolding tower may be manually rolled from place to place, comprising:
(1) also the said drive wheel;
(2) a drive wheel axle, concentrically attached to the drive wheel, having a threaded interior throughout and having one part of a tongue and groove mating system on the end attached to the drive wheel;
(3) a drive shaft, slidably attached to the drive wheel and having the complementary part of the tongue and groove mating system on the end slidably attached to the drive wheel, such that when the tongue and groove mating system is engaged the drive shaft, the drive wheel axle and the drive wheel rotate together;
(4) a turnscrew, threaded through the interior of the drive wheel axle, such that one end contacts the end of the drive shaft;
(5) a biasing spring;
and
(6) a turnscrew handle, attached to the turnscrew, such that turning the turnscrew handle in one direction causes the end of the turnscrew to push against the end of the drive shaft, thereby separating the drive shaft and the drive wheel axle, such that the tongue and groove mating system is disengaged, permitting the drive wheel to rotate freely with respect to the drive shaft, while turning the turnscrew handle in the other direction releases the pressure of the turnscrew against the end of the drive shaft, thereby permitting the biasing spring to push the drive shaft and drive wheel axle back together, thereby reengaging the tongue and groove mating system.

10 more elements

(a) a main frame;
(b) a pivotal attachment means connected to the main frame which pivotally attaches the scaffolding power unit to a single leg of the scaffolding tower assemblage;
(c) a drive wheel, rotatably attached to the main frame;
(d) a propelling means connected to the drive wheel which provides for linear motion of the scaffolding power unit and the attached scaffolding tower assemblage;
and
(e) a brake means, such that the drive wheel is restrained from rotation when the scaffolding power unit is not being used to move the scaffolding tower assemblage, comprising:
(1) also the said main frame;
(2) a brake release lever;
(3) a brake bar pivotally attached at the one end to the brake release lever and pivotally attached at the other end to the main frame;
(4) a brake pad, pivotally attached to the main frame and contacting the brake bar on one side such that rotation of the brake bar in one direction forces the brake pad against the drive wheel, thereby preventing the drive wheel from rotating, while rotation of the brake bar in the other direction releases the pressure on the brake pad, thereby freeing the drive wheel for rotation;
(5) a spring, attached at one end to the main frame and at the other end to the brake bar, such that it exerts a force on the brake bar, causing it to rotate, thereby pushing the brake pad against the drive wheel;
and
(6) a solenoid, pivotally attached to the brake release lever, such that energizing the solenoid overcomes the force of the spring and removes the brake pad from contact with the drive wheel, thereby permitting rotation of the drive wheel.

10 more elements

Dependencies are inferred from the claim text.