Improvements in Surgical Tables and Chairs.
Year: 1894

page_text: Date of Application, 5th Dec., 1894
Complete Specification Left, 4th Sept., 1895-Accepted, 5th Dec., 1895
PROVISIONAL SPECIFICATION.
Improvements in Surgical Tables and Chairs.
I, HENRY GEORGE LEISENRING, of Wayue, Nebraska, United States of
America, Surgeon, do hereby declare the nature of this invention to be as
follows:-
:-
My invention relates to improvements in surgical tables and chairs and
principally consists in means for raising and lowering same.
In carrying out my invention I provide an outside cylinder supported on legs at
its lower end, combined with an inside vertically moving cylinder having the table
or chair adjustably attached to its upper end, and a mechanism for raising and
lowering it; the cylinder being provided at its upper end with an air hole, and at
its lower end with a hollow plug, and a vertically moving valve that extends
through the plug and regulates the passage of oil into the cylinder when it is
being raised or lowered. A salient feature of my invention is to provide the
inside cylinder of a surgical table or chair with a valve which will allow the oil
in the cylinder to run out rapidly when the table or chair is being raised, and to
run very slowing into the cylinder when the table is being lowered. Or the raising
and lowering may be effected by a rack and pinion.
The invention is carried out in the following manner. The upper end of the
inner cylinder is contracted, on which the lower part of the standard rests and
turns, and in which is placed a plug, through which is made an air hole, through
which the air passes back and forth according as the oil is allowed to run out of
the cylinder when it is being raised, or to run slowly into it when the cylinder is
heing lowered. In the outside surface of the cylinder upon one side, is made a
series of ratchet teeth with which a pivotted pawl ou the inner end of the treadle
engages, and which treadle is held in a raised position when left free to move, by a
spring. While in a raised position the pawl allows the cylinder to freely descend,
but when the outer end of the treadle is depressed, the pawl engages with one of
the ratchet teeth and forces the cylinder upward, carrying the table or chair with
it. Also pivotted in the upper portion of the outer cylinder above the pawl, is a
second pawl, which engages with the ratchet teeth for the purpose of holding the
cylinder in a raised position while the first pawl is being lowered to engage with
another tooth, or simply to hold the cylinder stationary in any position into which
it may have been adjusted by means of the treadle. Operating in connection with.
the second pawl is a foot piece, by means of which the pawl can be moved, so as
to allow the cylinder and the table or chair attached to the upper end of it, to
descend either from their own weight or by the weight of the person on it. Through
the bottom of the inner cylinder which forms an oil chamber, is made a large
opening into which a hollow plug is screwed, the lower end of the plug being
made to project below the lower end of the cylinder. Through the upper end of
the plug which projects a suitable distance up into the inner cylinder are made
four large openings through which the oil passes with more or less rapidity,
according as the oil is being forced into the cylinder as it descends, or runs freely
from the cylinder as it is being raised. Extending through this plug is a valve
which is provided at its lower end with a disc, which is larger than the opening
through the plug, and through which disc are made several small openings, through
which the oil is slowly forced as the cylinder descends. To the valve stem are.
secured a suitable number of guides which project therefrom to the inner sides of
the opening through the plug and thus always keep the valve in an operative

page_text: position. To the upper end of the valve stem is secured a disc, which catches
upon the inwardly turned end of the plug, and thus prevents the valve from
becoming displaced. The valve playing freely back and forth through the plug,
according as the cylinder is raised or lowered, is automatic in its action and is
operated entirely by the movement of the oil. As the oil runs freely from the
cylinder, the cylinder can be rapidly raised, but as the oil is allowed to pass from
the outer cylinder to the inner cylinder very slowly, this cylinder will descend with
a slow, even, and regular movement.
Dated this 5th day of December 1894
FREDERIC PRINCE,
Agent for Applicant.
Improvements in Surgical Tables and Chairs.
I, HENRY GEORGE LEISENRING, of Wayne, Nebraska, United States of
America, Surgeon, 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:-
My invention relates to improvements in surgical tables and chairs and
principally consists in means for raising and lowering the same.
In carrying out my invention I provide an outside cylinder supported on legs at
its lower end, combined with an inside vertically moving cylinder, having the
table or chair adjustably attached to its upper end, and a mechanism for raising
and lowering it; the cylinder being provided at its upper end with an air hole and
at its lower end with a hollow plug, and a vertically moving valve that extends
through the plug and regulates the passage of oil into the cylinder when it is being
raised or lowered.
A. salient feature of my invention is to provide the inside cylinder of a surgical
table or chair with a valve which will allow the oil in the cylinder to run out
rapidly when the table or chair is being raised, and to run very slowly into the
cylinder when the table is being lowered, or the raising and lowering may be
effected by a rack and pinion. To enable this invention to be properly understood
I will proceed to describe the same with aid of the accompanying drawings.
Fig. 1 is a vertical section of the lower portion of the cylinder and its attachments
which embody my invention.
Fig. 2 is an enlarged view of the valve and the plug in which it operates.
Fig. 3 is a detail view showing the lever attachments for operating the
cylinder.
any
A, represents the outside cylinder to which the legs are attached in suitable
manner. Fitting snugly inside this cylinder is the inside cylinder C, to the upper
end of which the table or chair seat D is adjustably attached, and which cylinder
has a vertical movement in the outside one A, according as the table or chair is
being raised or lowered. At the upper end of the inner cylinder is the contracted
portion G, on which the lower part of the standard rests and turns, and in which
is placed a plug H, and through this plug is made an air hole I, through which
the air passes back and forth according as the oil is allowed to run out of the
cylinder C when it is being raised, or to run slowly into it when the cylinder is
being lowered. In the outside surface of the cylinder, upon one side, is made a
series of ratchet teeth J, with which the pivotted pawl L on the inner end of the
treadle M engages, and which treadle is held in a raised position when left free to
move by a spring N. While in a raised position the pawl L allows the cylinder
to freely descend, but when the outer end of the treadle M is depressed, the
pawl L engages with one of the ratchet teeth and forces the cylinder C upward,
carrying the table or chair with it. Also pivotted in the upper portion of the
outer cylinder A, above the pawl L, is a second pawl O, which engages with the

page_text: ratchet teeth J, for the purpose of holding the cylinder C in a raised position
while the pawl L is being lowered to engage with another tooth, or simply to
hold the cylinder stationary in any position into which it may have been adjusted
by means of the treadle. Operating in connection with the pawl O is a foot
piece P, by means of which the pawl Ŏ can be moved, so as to allow the cylinder C
and the table or chair attached to the upper end of the same to descend, either
from their own weight or the weight of the person on it.
Through the bottom of the cylinder C, which forms an oil chamber, is made a
large opening Qinto which the hollow plug R is screwed, the lower end of the
plug being made to project below the lower end of the cylinder as shown. Through
the upper end of the plug which projects a suitable distance up into the cylinder C
are made four large openings S through which the oil passes with more or less
rapidity, according as the oil is being forced into the cylinder C as it descends, or
runs freely from it as the cylinder is being raised. Extending through this plug R,
is a valve T, which is provided at its lower end with a disc U, which is larger
than the opening through the plug, and through which disc are made several small
openings V, through which the oil is slowly forced as the cylinder descends. To
the valve stem are secured a suitable number of guides, which project therefrom
to the inner sides of the opening through the plug and thus always keep the
valve in an operative position. To the upper end of the valve stem is secured the
disc X, which catches upon the inwardly turned end of the plug R, and thus
prevents the valve from becoming displaced. When the cylinder C is being raised
by the treadle M, the valve assumes the position shown in Fig. 2, and then the
oil runs from the cylinder C through the openings S, in the upper end of the plug
as fast as the cylinder is raised. The valve U having dropped below the lower
end of the plug offers but little obstruction to the flow of the oil, but when the
cylinder begins to descend, the valve U is forced tightly against the lower end of
the plug R, and then the oil can only pass from the outer cylinder A into the
one C through the small openings V, made through the valve for that purpose.
The valve playing freely back and forth through the plug, according as the
cylinder is raised or lowered, is automatic in its action, and is operated entirely
by the movement of the oil. As the oil runs freely from the cylinder, the cylinder
can be rapidly raised, but as the oil is allowed to pass from the outer cylinder A
to the cylinder C very slowly, the cylinder will descend with a slow, even and
regular movement, and that only when the foot piece P is operated so as to move
the pawl O and leave the cylinder free to descend.
Having now particularly described and ascertained the nature of my inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. A surgical table or chair having in combination with the inner cylinder C,
provided with a vent I, a hollow screw threaded plug R, having the lateral
openings S, the valve stem T provided with integral guide arms, plate X and a
perforated plate U, all contained within an outer cylinder A, and means as
described for raising and lowering the table or chair.
2. In a surgical table or chair, the combination of the cylinders A and C, the
latter supporting a swivelled table or chair D, the teeth J on said cylinder C, the
treadle M and pawl L, having a common pivotted centre, the said pawl at its inner
eud adapted to engage with the ratchet teeth J, and spring N, all substantially as
shown and described.
3. A surgical chair constructed and operating as described.
FREDERIC PRINCE,
37 Cursitor Street, London, E.C., Agent for Applicant.