IMPROVEMENTS IN MOTORS TO BE WORKED BY GAS
Year: 1874

page_text: LETTERS PATENT to Robert Gottheil, of the International Patent
Office, 126, Linden Strasse, Berlin, Prussia, Civil Engineer, for the
Invention of "IMPROVEMENTS IN MOTORS TO BE WORKED BY GAS." -A.
communication from abroad by Frederic Guillaume Gilles, of
Cologne, Prussia, Engineer.
PROVISIONAL SPECIFICATION left by the said Robert Gottheil at the
Office of the Commissioners of Patents, with his Petition, on the
2nd January 1874.
7
I, ROBERT GOTTHEIL, of the International Patent Office, 126, Linden
Strasse, Berlin, Prussia, Civil Engineer, do hereby declare the nature
of the said Invention for "IMPROVEMENTS IN MOTORS TO BE WORKED BY GAS,"
to be as follows:-
This Invention relates to engines for obtaining motive power from the
explosive combustion of gas and air without noise at little cost, and with
a construction simple and capable of easy repair. I employ an elongated

page_text: cylinder open at one end, which is provided with two pistons.
The one
which may be termed the working piston is connected in the usual way
to a crank on the main shaft which is provided with a fly wheel. The
other piston which may be termed the loose piston has a rod passing
through the cylinder cover and through two friction cheeks mounted on
levers in such a manner that they admit of the free movement of the
piston rod in the one direction, but its movement in the opposite
direction is stopped by its causing the cheeks to embrace the rod tightly,
until the cheeks are relieved by the action of an eccentric at a certain
point in each revolution of the crank shaft. At the side of the cylinder
near the middle of its length is an opening fitted with a slide which is
worked by a cam on the crank shaft. In this slide which may be
termed the gas slide, and in its jacket are provided passages for the
ingress and mixture of air and inflammable gas and of a kindling
flame. The rod of this slide extended works another slide which may
be termed the air slide near the cylinder cover so as to cover and
uncover once in every revolution a passage for the ingress of air to the
cylinder. There are also near the same end of the cylinder a number of
small holes covered by an india-rubber ring for the issue of air from the
cylinder, and further there is between the gas slide and the air slide an
opening from the cylinder provided with a valve opening outwards
for the discharge of the products of combustion.
The operation of the engine is as follows:-Assuming that the
working piston is at the extreme of its stroke inwards, the loose piston
being close to it, the former by the rotation of the crank is drawn
outwards, and the loose piston having on its opposite side the pressure
of the air entering by the air slide follows the working piston till it is.
stopped by a cross head on its rod meeting buffers provided on the
cylinder cover. The working piston continuing its movement creates a
partial vacuum behind it in the space between it and the loose piston.
The cam having moved the gas slide so as to admit into this space the
mixture of air and gas, admits the kindling flame whereby the mixture
is exploded.
The pressure produced by the explosion forces onwards the working
piston, and at the same time causes the loose piston to make a rapid
stroke in the opposite direction, the air in the space beyond it being
discharged through the holes near the end of the cylinder. When the

page_text: loose piston covers these holes the remaining air serves as a cushion to
arrest its movement. The working piston having made its outward
stroke, and the loose piston having also made its outward stroke and the
gas slide having closed the space in the cylinder between the two
pistons remains charged with the products of combustion at a pressure
considerably below that of the atmosphere. The atmospheric pressure
therefore tends to force both pistons inwards. The working piston
moves inwards in obedience to this pressure, but the loose piston is held
near the extreme of its out-stroke by the friction cheeks above referred
to, the ingress of air beyond it being prevented by the india-rubber band
closing the air holes.
When the working piston is approaching the extremity of its in-stroke
the friction cheeks are slackened off the rod of the loose piston by the
action of the eccentric, and the air slide is opened. The loose piston
thereupon makes a rapid stroke inwards till it nearly meets the working
piston, and the products of combustion thus compressed between the
two pistons are forced out by the discharge valve on the side of the
cylinder, the action is then repeated.
By placing the cylinder in an upright position the weight of the
working piston is made available to assist its out-stroke, and the weight
of the loose piston to assist its in-stroke.
From the above description it will be seen that the engine is double-
acting, a portion of the out-stroke of the working piston being effected
by the pressure of the explosion, and its in-stroke by the excess of the
atmospheric pressure over that of the products of combustion. Two or
more such engines may be connected to one shaft so as to diminish
irregularities of action.
Small engines of the kind described above with the cylinder vertical,
and the loose piston uppermost may have the cylinder open at top, thus
dispensing with the air holes and air slide, the weight of the loose piston.
being suitably proportioned to the pressure developed by the explosion. +

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Robert Gottheil in the Great Seal Patent Office on
the 1st July 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
GOTTHEIL, of the International Patent Office, 126, Linden Strasse,
Berlin, Prussia, Civil Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Second day of January, in the year
of our Lord One thousand eight hundred and seventy-four, in the
thirty-seventh year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Robert Gottheil, Her special
license that I, the said Robert Gottheil, my executors, administrators,
and assigns, or such others as I, the said Robert Gottheil, my executors,
administrators, and assigns, should at any time agree with, and no
others, from time to time and at all times thereafter during the term
therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdoni of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
MOTORS TO BE WORKED BY GAS," a communication to me from abroad by
Frederic Guillaume Gilles, of Cologne, Prussia, Engineer, upon the
condition (amongst others) that I, the said Robert Gottheil, my
executors or administrators, by an instrument in writing under my, or
their, or one of their hands and seals, should particularly describe and
ascertain the nature of the said Invention, and in what manner the
same was to be performed, and cause the same to be filed in the
Great Seal Patent Office within six calendar months next and imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Robert Gottheil, do hereby declare
the nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement thereof, reference being had to the accompanying
Sheet of Drawings, and to the figures and letters marked thereon, that is
to say:-
This Invention relates to engines for obtaining motive power from the
explosive combustion of gas and air without noise at little cost, and with
a construction simple and capable of easy repair. An elongated cylinder

page_text: open at one end is provided with two pistons. The one which may be
termed the working piston is connected in the usual way to a crank on
the main shaft which is provided with a fly wheel. The other piston
which may be termed the loose piston has a rod passing through the
cylinder cover, and through two friction cheeks mounted on levers in
such a manner that they admit of the free movement of the piston rod
in the one direction, but its movement in the opposite direction is
stopped by its causing the cheeks to embrace the rod tightly, until the
cheeks are relieved by the action of an eccentric at a certain point in
each revolution of the crank shaft. At the side of the cylinder near the
middle of its length is an opening fitted with a slide which is worked by
a cam on the crank shaft. In this slide which may be termed the gas
slide and its jacket are provided passages for the ingress and mixture
of air and inflammable gas and of a kindling flame. The rod of this
slide extended works another slide which may be termed the air slide
near the cylinder cover so as to cover and uncover once in every
revolution a passage for the ingress of air to the cylinder.
There are
also near the same end of the cylinder a number of small holes covered
by an india-rubber ring for the issue of air from the cylinder, and.
further there is between the gas slide and the air slide an opening from
the cylinder provided with a valve opening outwards for the discharge of
the products of combustion.
The operation of the engine is as follows:-Assuming that the
working piston is at the extreme of its stroke inwards, the loose piston
being close to it, the former by the rotation of the crank is drawn
outwards, and the loose piston having on its opposite side the pressure
of the air entering by the air slide follows the working piston till it is
stopped by a cross head on its rod meeting buffers provided on the
cylinder cover. The working piston continuing its movement creates a
partial vacuum behind it in the space between it and the loose piston.
The cam having moved the gas slide so as to admit into this space the
mixture of air and gas, admits the kindling flame whereby the mixture
is exploded.
The pressure produced by the explosion forces onwards the working
piston, and at the same time causes the loose piston to make a rapid
stroke in the opposite direction, the air in the space beyond it being
discharged through the holes near the end of the cylinder. When the
loose piston covers these holes the remaining air serves as a cushion to

page_text: :.
arrest its movement. The working piston having made its outward
stroke and the loose piston having also made its outward stroke, and the
gas slide having closed the space in the cylinder between the two pistons.
remains charged with the products of combustion at a pressure.
considerably below that of the atmosphere. The atmospheric pressure
therefore tends to force both pistons inwards. The working piston moves
inwards in obedience to this pressure, but the loose piston is held near
the extreme of its out-stroke by the friction cheeks above referred to, the
ingress of air beyond it being prevented by the india-rubber band
closing the air holes.
When the working piston is approaching the extremity of its in-stroke
the friction cheeks are slackened off the rod of the loose piston by the
action of the eccentric and the air slide is opened. The loose piston
thereupon makes a rapid stroke inwards till it nearly meets the working
piston, and the products of combustion, thus compressed between the
two pistons are forced out by the discharge valve on the side of the
cylinder, the action is then repeated.
By placing the cylinder in an upright position the weight of the
working piston is made available to assist its out-stroke, and the weight
of the loose piston to assist its in-stroke.
From the above description it will be seen that the engine is double-
acting, a portion of the out-stroke of the working piston being effected
by the pressure of the explosion, and its in-stroke by the excess of the
atmospheric pressure over that of the products of combustion. Two or
more such engines may be connected to one shaft so as to diminish 2
irregularities of action.
Small engines of the kind described above with the cylinder vertical,
and the loose piston uppermost, may have the cylinder open at top, thus
dispensing with the air holes and air slide, the weight of the loose piston
being suitably porportioned to the pressure developed by the explosion. E
DESCRIPTION OF THE DRAWINGS.
Fig. 1 represents a vertical section; and Fig. 2, a side elevation of an
engine constructed according to this Invention; Fig. 3, being a part
section shewing the slide in the lower part of its stroke.
A is the cylinder fitted with the working piston B and the upper 3
piston C, the former piston being connected by a connecting rod to the

page_text: crank on the fly wheel shaft below. On this shaft is the cam O' which.
works the slides D and u, and the eccentric p which releases the clamp
of the upper piston rod. The slide D has in it a cavity e and a sloped
passage d, g, and the slide jacket has ports b and c for the admission of
gas and air, a port i for admitting the kindling flame to the passage d, g,
which communicates also with an air port h. The passage a into the
cylinder in one position of the slide admits the mixture of air and gas
supplied to the cavity e, and during the rapid movement of the slide admits
the kindling flame which ignites, the mixture in the cylinder. The
slide u which moves with the lower slide D governs the passage v for
admitting air to the cylinder above the piston C. The caoutchouc.
band covers a number of holes s, 8, bored through the cylinder, the
band opening sufficiently to let air issue by these holes from the cylinder
when the piston C ascends, but closing the holes against ingress of air
to the cylinder. The passage w governed by the valve x permits the
products of combustion to issue from the cylinder, the valve x closing to
prevent ingress to the cylinder. The cross head on the rod of the
upper piston bears on the clastic buffers "", ¹, when the piston C
descends.
The apparatus for clamping the rod of this piston and preventing it
from descending till the grip is relieved, consists of two levers m, m,
pressed down by springs and prevented from rising too high by
adjustable stop screws n, n. The ends of the two levers m, m, are
rounded and enter notches in a pair of clamps 1, which consist of a
bush made in halves enclosing the piston rod. The levers m, m, are a
little inclined upwards so that as they tend to come down to a horizontal
position, they press the sides of the clamp 7 firmly against the piston rod
and grip it, thereby preventing it from descending until the eccentric p
which is connected to the lever o is brought round to such a point in its
revolution as to raise the inner end of the lever o, pushing upwards the
clamp, and so relieving the piston rod and allowing the piston C to
descend.

page_text: propel two pistons in opposite directions, the one piston being connected
to a crank on a fly wheel shaft, and the other being after its propulsion
held for a time by a clamp for the purpose of utilizing as motive power
the reduction of pressure within the cylinder after explosion, substantially
as herein described.
Second. The use for clamping and releasing the piston rod in a gas
engine of the kind referred to above of the combined apparatus consisting
of spring levers set in an inclined position so as to press the parts of a
divided bush against the rod, and of a lever worked by an eccentric so as
to raise the divided bush relieving the rod of its pressure, substantially
as herein described.
In witness whereof, I, the said Robert Gottheil, have hereunto set
my
hand and seal, this Twentieth day of June, in the year of
our Lord One thousand eight hundred and seventy-four.
ROBERT GOTTHEIL. (L.S.)