IMPROVE- MENTS IN HOISTING MACHINES OR MACHINES FOR RAISING AND LOWERING HEAVY BODIES
Year: 1882

page_text: PROVISIONAL SPECIFICATION left by Thomas King at the Office of the
Commissioners of Patents on the 12th January 1882.
THOMAS KING of Birmingham in the County of Warwick Butcher. "IMPROVE-
MENTS IN HOISTING MACHINES OR MACHINES FOR RAISING AND LOWERING
HEAVY BODIES."
My Invention consists in constructing and arranging in the manner hereinafter
described the parts of hoisting machines or machines for raising and lowering
heavy bodies whereby the said hoisting machines are made simple in construction,
efficient in action and not liable to derangement.
Machines constructed according to my Invention have the further advantage
that they will not run down that is the weight raised remains suspended at the
point to which it has been raised without the maintenance of tension in the raising.
rope or chain. For greater security however a pawl and ratchet wheel' may be
employed.
In a strong frame by which the machine is supported by a hook or otherwise
a vertical axis carrying a drum is mounted. At the top of the drum is a worm
wheel and the bottom of the drum has a flange. A worm carried by a horizontal
axis working in bearings in the upper part of the frame engages with the worm
wheel at the top of the drum. On one end of the axis carrying the worm a
sprocket wheel is fixed the endless rope or chain by which the machine is worked
passing over the said sprocket wheel.
The weight or article to be raised or lowered is suspended to a cord or chain
which is coiled several times around the drum. By giving rotation to the drum
by means of the endless rope or chain on the sprocket wheel the suspending_cord
or chain is coiled on the lower end of the drum and payed off the upper end and
the suspended weight or article is raised or by motion of the drum in the contrary
direction the weight or article is lowered.
In order to guide the rope or chain on or off the lower end of the drum and to
guide it from or to the upper end of the drum as well as to adjust the position of
the coiled rope or chain on the drum the following arrangements are adopted.
Immediately below the flange at the bottom of the drum is a horizontal axis
carried by the frame. On this axis a flanged roller works and the vertical rope or

page_text: chain carrying the weight or article to be raised passes over this roller and is
guided by it on or off the drum. The upper end of the rope or chain passes over a
roller near the top of the drum. A third roller turning on an axis carried by a
cross support comes very close to but not into contact with the drum near its lower
end. The rope or chain after passing once round the drum passes over the said
third roller and by the said roller the coil passing over it as well as the coils
above it are slightly raised upon the drum and the coils on the drum are thus
made to occupy the same part of the drum however much cord or chain may be
passing on to the drum at the bottom and passing off from it at top. Instead of
only one roller for adjusting the position of the cord or or chain upon the drum
more than one roller may be employed or a roller may be applied to and made to
adjust each coil.