Improvements in Portable Pneumatic Apparatus for Dressing Stone and other Purposes.
Year: 1888

page_text: PROVISIONAL SPECIFICATION.
.
Improvements in Portable Pneumatic Apparatus for Dressing Stone
and other Purposes.
We, JOHN JAMES MANN, of Ordsall. Lane Mills, Salford, in the County of
Lancaster, Manufacturer, REGINALD ARTHUR SMITH of 24, Brasenose Street, Man-
chester in the County of Lancaster, Electrical Engineer, and CHARLES MARK
DORMAN, of 24, Brasenose Street, Manchester in the County of Lancaster, Electrical
Engineer do hereby declare the nature of this invention to be as follows:
Our invention relates to that class of portable pneumatic apparatus for dressing
stone &c., commonly known as pneumatic tools.
In appliances of this nature now in use a reciprocating motion only is given to
the tool, the stone or other material being cut away by a series of percussive blows
delivered on the tool-carrier hy a heavy reciprocating piston, the tool-carrier being
brought back after each blow by the action of a spring.
The object of our invention is to cause a rotary motion to be transmitted to the
tool in addition to its reciprocating motion.
To carry out our invention we cause a disc or wheel bearing teeth or palates to
derive a step by step rotary movement through palates or teeth from the reciproca-
ting motion of the piston, or tool holder, the said disc or wheel being attached to the
spindle of the tool holder by a feather or other convenient method whereby rotary
motion can be transmitted to the tool holder after the manner of a driving escape-
ment.
.
In one method of carrying our invention into effect we affix on the reciproca-
ting spindle forming the tool carrier a disc or flange at right angles to the axis
of the spindle. This disc is provided with teeth which at every reciprocation
of the spindle engage with stationary teeth or palates, by which means a rotary
step by step motion of the tool carrier is obtained after the manner of a driving
escapement.
When it is desired that the tool shall have a simple reciprocating without a rotary
motion we draw out a catch which leaves the previously fixed palates or teeth free
to turn round the spindle, and throw in a feather or catch which restrains the
spindle to reciprocate without revolving.
Dated this 23rd day of March 1888
.

page_text: COMPLETE SPECIFICATION.
Improvements in Portable Pneumatic Apparatus for Dressing Stone
and other Purposes.
We, JOHN JAMES MANN of Ordsall Lane Mills, Salford, in the County of Lancaster,
Manufacturer, REGINALD ARTHUR SMITH, of 24, Brazenose Street, Manchester in
the county of Lancaster. Electrical Engineer, and CHARLES MARK DORMAN, of
24 Brazenose Street Manchester, in the County of Lancaster, Electrical 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
Our invention relates to that class of portable pneumatic apparatus for dressing
stone, etc. commonly known as pneumatic tools.
In appliances of this nature now in use a reciprocating motion only is given to
the tool the stone or other material being cut away by a series of percussive blows
delivered on the tool-carrier by a heavy reciprocating piston, the tool-carrier being
brought back after each blow by the action of a spring.
The object of our invention is to cause a rotary motion to be transmitted to the
tool in addition to its reciprocating motion.
To carry out our invention we cause a disc or wheel bearing teeth or palates to
derive a step by step rotary movement through palates or teeth from the reciproca-
ting motion of the piston, or tool holder the said disc or wheel being attached to the
spindle of the tool holder by a feather or other convenient method whereby rotary
motion can be transmitted to the tool holder after the manner of a driving escape-
ment.
In one method of carrying our invention into effect we fix on the reciprocating
spindle forming the tool carrier a disc or flange at right angles to the axis of the
spindle. This disc is provided with teeth, which at every reciprocation of the
spindle engage with stationary teeth or palates, by which means a rotary step by stepi
motion of the tool-carrier is obtained after the manner of a driving escapement.
Referring to the drawings accompaning this specification Fig. 1. is a sectional
elevation of our improved rotary step by step motion applied to a reciprocating
pneumatic tool holder.
Fig. 2. is an elevation of one end of the reciprocating tool-carrier showing the
wheel having teeth cut in its upper and lower faces. The action of the arrangement
can be described as follows:-A piston or plunger a. is made to reciprocate in its
cylinder under the influence of compressed air or other fluid causing a continuous
rain of blows on the top end b. of the tool-carrier. The reciprocations of the escape
wheel c. takes place between two fixed palate wheels e. and f. having similar teeth to
those on the escape wheel.. The escape wheel c is constrained to remain against the
top palate wheel e by the spring d. On a downward movement of the piston a taking
place, the tool-carrier is driven down and with it the escape wheel c, the teeth on
the underside of which, gear with those on the uppper side of the palate wheel fand

page_text: cause the tool holder and with it the cutting tool to revolve a distance of half a tooth.
An upward movement of the piston now takes place when the tool carrier and escape
wheel are lifted by the spring d, the teeth on the upper face of the escape wheel c
now gearing with those on the lower side of the palate wheel e causing the tool-
carrier to again revolve a distance of half a tooth. The same action going on
continuously it will be seen that as long as the reciprocating motion continues a
rotary motion will also take place.
We find in practice that it is advisable to introduce a washer g between the top of
the spring d and the enlarged upper end of the tool-carrier. This washer g is fitted
with a feather as shown and is free to reciprocate but cannot revolve. Its office is
to cause a requisite amount of friction to exist between it and the enlarged part of
the tool-carrier, to ensure no rotary motion of the escape wheel c taking place
except when it is gearing with either of the palate wheels. In fact it acts like the
friction brake generally necessary in a driving escapement.
Fig 3. is a section on the line ... shewing the teeth on the upper face of the
palate wheel f
Fig. 4 is a section on the line y. y. through the friction washer g.
When it is desired that the tool shall have a simple reciprocating, without a rotary
motion, we draw out a catch which leaves the previously fixed palates or teeth froe
to turn round the spindle and throw in a feather or catch which restrains the spindle
to reciprocate without revolving.
Having now particularly described and ascertained the nature of our said Inven-
tion, and in what manner the same is to be performed, we declare that what we.
claim is
1st. In apparatus for dressing, carving, and cutting stone or other material in
which reciprocating motion is given to the cutter through the motion of a piston in a
cylinder; the method of causing a step by step rotary motion to take place in the tool-
carrier, through teeth cut in the upper and lower faces of an escape wheel fixed to the
tool holder, gearing alternately in similar teeth cut in fixed palate wheels, the escape
wheel and with it the tool-holder revolving a distance of one tooth at every complete
stroke substantially as described and shown.
Dated this 22nd day of January 1889