Improvements in Hydraulic Capstans or Mechanism Used in Connection therewith.
Year: 1887

page_text: Improvements in Hydraulic Capstans or Mechanism Used in
Connection therewith.
I, WILLIAM SHAPTON of 8 Great George Street in the City of Westminster,
Engineer do hereby declare the nature of this invention to be as follows:-
Hydraulic capstans as ordinarily constructed only turn in one direction unless
provision is made for reversing the engine which complicates the machine and
increases the cost.
With capstans so formed, if the rope when being wound on to the capstan barrel
gets jammed much trouble is experienced in getting it free as the fluid in the
cylinders blocks the engine and prevents the capstan being eased back.
To obviate this, on the pipe through which fluid under pressure is supplied to the
engine I place between the engine and the valve ordinarily controlling the passage
of fluid to the engine an additional valve which when opened will allow the fluid in
the engine to flow into the exhaust and so allow the capstan to be turned back by the
strain on the rope or by hand, the ordinary controlling valve having previously been
closed. Or in place of this arrangement a single D slide valve working over two
ports may be used and made to serve not only as a regulating valve for controlling the
admission of fluid under pressure to the engine but also for allowing fluid to be
passed back from the engine to the exhaust whenever the engine has to be turned
backwards.
CARPMAEL & Co.,
Agents for the Applicant.

page_text: Improvements in Hydraulic Capstans or Mechanism Used in
Connection therewith.
I, WILLIAM SHAPTON of 8 Great George Street in the City of Westminster,
Engineer, do hereby declare the nature of this invention and in what manner the
same is to be performed to be particularly described and ascertained in and by
the following statement :-
Hydraulic capstans as ordinarily constructed only turn in one direction unless
provision is made for reversing the engine which complicates the machine and
increases the cost.
With capstans so formed, if the rope when being wound on to the capstan barrel
gets jammed much trouble is experienced in getting it free as the fluid in the cylinders
blocks the engine and prevents the capstan being eased back.
To obviate this I use in addition to the valves ordinarily controlling the passage of
the fluid to and from the engine a valve which when opened will allow the fluid in the
engine to flow into the exhaust and so allow the capstan to be turned back by the
strain on the rope or by hand, the ordinary controlling valve having previously
been closed. Or in place of this arrangement a single D slide valve working over
two ports may be used and made to serve not only as a regulating valve for
controlling the admission of fluid under pressure to the engine but also for allowing
fluid to be passed back from the engine to the exhaust whenever the engine has to be
turned backwards.
Figure 1 is a plan view and Figure 2 a section of the arrangement of valves I
prefer to use for effecting the above object.
It consists of three valves A, B and C-the valve A is for controlling the supply of
water under pressure to the engine-the valve B closes a passage between the pressure
supply to engine and the exhaust. By the valve C the exhaust from engine can be
closed. It is not essential to provide a valve for closing the exhaust but it is convenient
to do so to enable the engine to be overhauled or repaired when adjacent machines
connected to the same system of exhaust mains are at work. Normally when the
capstan is working the valves A and C are open and B shut but when it is necessary
to ease back A is closed and B opened.
The diagram, figure 3, shows how the same object can be effected by a D slide
valve.
A and B are two ports-by the port A water under pressure passes to the engine
the port B leads to the exhaust. When the D valve is in the position shewn in the
diagram and the port A is uncovered water under pressure passes to the engine-when
the port A is covered by the flat face of the D valve the supply of water to the engine

page_text: is cut off and when the valve is moved still further and the hollow of the D valve is
over both ports the engine can be eased back.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is
The combination with hydraulic capstans which are constructed to work in one
direction only of a valve on the pressure water supply pipe or passage to the engine to
permit of water being passed back through it from the engine to the exhaust when-
ever the engine has to be eased back.