U.S. patent number 3,731,758 [Application Number 05/103,555] was granted by the patent office on 1973-05-08 for scaffold drive and steering unit.
This patent grant is currently assigned to Anne Marie Hibma. Invention is credited to James Hibma.
United States Patent |
3,731,758 |
Hibma |
May 8, 1973 |
SCAFFOLD DRIVE AND STEERING UNIT
Abstract
A scaffold unit for construction and maintenance activities
which provides a reversible drive motor at a fixed support wheel
for propelling the scaffold and a motorized steering apparatus for
the directional control of said scaffold by steering at least one
castor mounted support wheel. The drive and steering motors are
connected to a control panel that is movable to various elevated
and/or remote locations. Electric drills may be used for said
motors.
Inventors: |
Hibma; James (Westminster,
CO) |
Assignee: |
Hibma; Anne Marie (County of
Adams, Westminster, CO)
|
Family
ID: |
22295812 |
Appl.
No.: |
05/103,555 |
Filed: |
January 4, 1971 |
Current U.S.
Class: |
180/11; 180/443;
180/65.6; 182/63.1 |
Current CPC
Class: |
B60P
3/14 (20130101); E04G 1/24 (20130101); E04G
2001/244 (20130101) |
Current International
Class: |
E04G
1/24 (20060101); E04G 1/00 (20060101); B60P
3/14 (20060101); B60k 007/00 () |
Field of
Search: |
;180/11,26R,65F,65R,15,12,79,79.1,60 ;182/14,63 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Sheridan; Robert G.
Assistant Examiner: Abraham; George F.
Claims
I claim
1. A drive and steering attachment for scaffolding type supports
having upright standards that in scaffolding usage may be mateably
engaged one above another when multi stages are to be used and
wherein each of said standards are further adapted to receive
separate supporting wheel attachments when increased mobility is
advantageous comprising a plurality of separable and separate wheel
attachments for said support with a wheel attachment for each
standard, wheels for each said attachment, frame components for
each attachment, wheel axles on said frame components for the
rotative support of said wheels, means for separately and
selectively engaging each of said wheel attachments with the
upright standards of said supports, means facilitating the rotative
movement of a plurality of said frame components with respect to
the vertically disposed axis of the associated support upright to
provide a castor type mounting for said plurality of frame
components and wheels, an anchor element on said support for
non-moving relationship therewith, motive drive means
interconnecting said anchor element and at least one of aid castor
wheels to provide a steerable wheel whereby said steerable wheel
and its associated frame component may be rotated to forwardly and
laterally directed positions with respect to the axis of its
associated upright and said support, a mount adjacent the frame
component of one wheel attachment, a motor drive unit on said
mount, drive reduction means intermediate said motor and the wheel
of said attachment, means for reversing the drive rotation of said
wheel to power forward and reverse movement operations of said
wheel attachment, and power control apparatus interconnected to
said motive drive means and said motor drive unit whereby an
operator may conveniently steer and drive said support unit.
2. The combination as set forth in claim 1 wherein said motive
drive means is interconnected to only one steerable wheel.
3. Structure as set forth in claim 1 wherein said steerable wheel
and its associated frame component may be rotated through an arc
greater than ninety degrees.
4. Structure as set forth in claim 3 wherein electric power control
apparatus is provided.
5. The combination as set forth in claim 1 wherein the drive motors
are removable and wherein a high drive ratio is provided for said
drive reduction means for resisting unpowered movement of said
scaffold.
6. The combination as set forth in claim 4 wherein at least one
support wheel for said scaffolding is fixed and said motor drive
unit is operatively connected to such fixed support wheel.
7. The combination as set forth in claim 4 wherein a cable
interconnects the control apparatus to said power steering means
and to said motor drive unit.
8. The combination as set forth in claim 4 and additionally
comprising a speed change component for varying the speed of said
motor drive unit.
9. The combination as set forth in claim 4 and further comprising
reversing means for said motor drive unit.
Description
BACKGROUND OF THE INVENTION
In connection with construction of maintenance operations, it is
often advantageous for a workman to have a scaffold support so that
he can work at high elevations with safety. Where ceilings or
utilities are being installed or where lighting and heating systems
are to be maintained, a rolling type scaffold is often used that
may be conveniently moved to various work locations. Manipulation
of the usual castor wheel supported scaffold generally requires an
additional workman who can push and guide the scaffold and the
workmen supported thereby to successive work stations. In order to
avoid this obvious misuse of labor, others have previously devised
scaffold propelling and steering systems that may be operated by a
workman at his elevated work station. In general, the previous
systems have been quite expensive. It is believed that the overall
expense and the inconvenience of using and storing prior types of
steering and drive apparatus have been detrimental to the
widespread use of such systems. The present invention is intended
to overcome shortcomings of the previous systems.
SUMMARY OF THE INVENTION
Briefly stated, the present invention provides attachments that may
be applied to wheel supported scaffold units to propell the units
and to steer the entire scaffold so that a single workman can move
the scaffold and himself to successive work stations. A first drive
unit provides a drive reduction system and a mounting for a drive
motor. The motor and drive reduction are connected to one support
wheel of the scaffold. A steering unit is similarly affixed to the
scaffold in position adjacent a castor type wheel to steer the
wheel. A crank arm is powered by a steering motor, and the crank
arm is connected by a steering rod to a steering arm associated
with the pivoted wheel. Either or both motor devices may use a
conventional electric drill which may itself provide a substantial
gear reduction. Both motor devices are connected to a remote
steering control unit that may be positioned adjacent the work
platform. Steering and drive control is obtained by manipulation of
control elements.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view showing a preferred embodiment of the
invention,
FIG. 2 is a plan view taken along the line 2--2 of FIG. 1 and
illustrating the steering control unit,
FIG. 3 shows an electric drill for use as a motor drive,
FIG. 4 is a top view taken along the line 4--4 of FIG. 1,
FIG. 5 is a side elevation of the drive mechanism as shown in FIG.
4, and
FIG. 6 is an illustration of the remote control apparatus.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1 a preferred embodiment of the invention is shown. Here a
scaffold unit 11 is shown to be of somewhat conventional
construction with the end frames 12 and 13 being joined together by
cross braces 14. The cross braces are engaged in lock receptacles
16 on the upright standards 17. While a single height scaffold is
shown for convenience of illustration, it should be recognized that
the upper ends 18 of the upright standards 17 are adapted to
receive a pin of additional scaffold components so that the total
height of the scaffold system may be increased to as much as 3 or 4
units.
At the lower ends of the scaffold standards 17, support wheels are
provided. The wheel 19 may be fixed with respect to its associated
standard 17, or it may be a freely pivoting castor wheel. Support
wheels 21 are castor wheels that are free to turn with respect to
their standards 17. A separate "front" wheel 22 is likewise of a
castor type. Provision is made for guiding and steering this wheel
22. Remaining wheel 23 is a drive disposed in fixed position with
respect to its associated standard 17.
A platform 24 is welded or formed integrally with the forked
support 26 for drive wheel 23. The platform provides support for an
electrically powered drive motor 27. As best shown in FIGS. 4 and 5
the output power from drive motor 27 is connected by a drive belt
28 to a jack shaft 29 that is itself rotatably mounted on platform
24. A further input gear or sprocket 31 is also mounted on jack
shaft 29 to turn therewith and to deliver power by means of the
drive chain 32 to a driven sprocket 33 mounted on the axle 34 of
drive wheel 23. Rotation and power provided by the drive motor 27
then serves to rotate the drive wheel 23. Since the direction of
rotation for the drive motor 27 is reversible, the end frame 12 may
then be moved forwardly and rearwardly to propell such end frame
and the entire scaffold unit 11. Since a relatively slow moving
speed will be satisfactory, the drive reduction provided by the
pulley sprocket system illustrated will, together with any gear
reduction in the motor unit itself, give close control over the
scaffold drive speed. For either maintenance or construction
operation uses, it has been found that the motor of an electric
drill can be used beneficially for this purpose since reversible
and multispeed drills are available at a reasonable cost. Such
electric drills may be provided with a drive pulley 36 to serve
this auxiliary purpose. For the particular type of electric drill
illustrated the handle has been removed, and the handle mounting is
directly applied to a support frame 37. For other uses the support
frame could include elements for grasping the drill handle to
provide an adequate mount. Similarly, a spindle for drive pulley 36
can be engaged in the chuck of an electric drill so that the drill
can be used without modification. This alternate configuration is
shown in FIG. 3 where the drill chuck 38 receives and holds the
spindle 39 of a drive pulley 36. Where this alternate system is
used the drill can be used for conventional drilling operations
when it is not in use as a scaffold drive component. A heavy duty
three-eighths inch drill or a one-half inch drill can be
successfully used in either of the described installations.
With the fork supports of two or three of the scaffold support
wheels being free to turn with respect to the upright standards 17,
some steering system is required for controlling the direction of
travel for the scaffold unit 11. Powered components for a preferred
steering system are shown in FIGS. 1 and 2. Here a steering motor
41 is interconnected to a gear box drive 42. The steering motor 41
is reversible and it is used to move a crank arm 43 to alternate
positions. Preferably limit stops are provided by the motor or gear
box or in association with the crank arm 43 so that the crank arm
will move only in an arcuate pattern. A steering rod 44 is
connected to the crank arm 43 and the steering rod is itself
connected to an arm 46. Arm 45 moves with the support forks for
front wheel 22 and causes rotation thereof with respect to its
associated standard 17. Since thrust bearings are used between the
standards and all of the castor type wheels, a low order of power
will cause pivoting of the wheel 22. As the wheel 22 is turned, the
entire scaffold will be steered in the direction that the wheel 22
is turned.
Cables 47 and 48 interconnect the drive motor 27 and the steering
motor 41, respectively, to a remote control unit 49. The control
unit 49 is provided with mounting brackets 51 so that it may be
positioned on a cross bar 52 of the scaffold unit at any position
convenient to a workman standing on support planks or deck 53. A
substantial length of cable is provided so the control unit 49 may
be moved to a next higher scaffold and to convenient operative
position at a work deck that may be 20 to 30 feet above the
supporting floor.
The remote control unit 49 as shown in FIGS. 1 and 6 provides drive
and steering controls 54 and 56, respectively. The toggle of the
drive control may be moved to forward, neutral and reverse
positions, while the toggle of the steering control 56 is moved to
left and right positions to correspondingly energize the associated
motors. Signal lights are provided with the drive light 57
indicating when the drive motor is energized, and a steering light
58 gives indication of steering unit actuation. A power cable 59
provides power to the remote control unit 49 and through such
control unit to the drive and steering components. A rheostat speed
control 61 is provided to further control the propulsion speed for
the scaffold unit 11.
With this type of scaffold unit a single workman may install
plumbing, electrical or heating utilities or suspended ceilings or
lighting systems. Similarly the scaffold may be used for the
maintenance of such systems as in the replacement of fluorescent
lights, etc. A stock of parts may be carried to the upper
supporting deck 53 and thereafter a plurality of operations can be
accomplished before a workman would have to come down.
The movable control system is especially beneficial for one-man
operation, since the control unit can at all times be placed
adjacent the work station. Further, the control unit 49 is of light
weight, and it may be readily moved to the top platform or to a
position near the supporting ground. When the scaffold is moved
from one work station to another, the control box may be carried or
attached to the scaffold at a low elevation for manipulation by a
walking workman.
When the scaffold is to be used at unimproved work sites, the
support wheels will usually be of larger diameter or of a pneumatic
type so that the scaffold can be moved across and over minor
obstructions. Pneumatic wheels are or useful when the scaffold is
to be used over unimproved floors or on uncompacted earth
surfaces.
The gear or power reduction used in the drive system is usually
sufficient to prevent free-wheeling movement of the scaffold. This
feature prevents undesired movement unless the drive or steering
motors are actuated, and it further prevents unauthorized use of
misuse of the scaffold. Actually when the unit is to be left
over-night, the drive and steering motors can be conveniently
removed to be left in secure storage. The gear reduction or power
reduction drive is sufficient to prevent undesirable movement of
the scaffold even when the motors are removed. Where an electric
drill motor is used, the electric drill may be removed for storage
or other useage at times when it is not to be used for scaffold
drive and steering operations.
* * * * *