Improvements in Clams or Clamps for Lathes.
Year: 1890

page_text: Date of Application, 27th Nov., 1890
Complete Specification Left, 14th Aug., 1891-Accepted, 26th Sept., 1891
PROVISIONAL SPECIFICATION.
Improvements in Clams or Clamps for Lathes.
We CHARLES TAYLOR and GEORGE BENJAMIN TAYLOR both of Bartholomew
Street Birmingham in the County of Warwick Machinists do hereby declare the
nature of this invention to be as follows:-
Our invention has reference principally to the clams or clamps used in lathes; in
which clams or clamps the get or other waste piece of the article to be turned in the
lathe is held. Such clamps open only to a small angle. Our invention is however
also applicable to clamps generally for lathes.
According to one of our improvements we dispense with the joint by which the
loose jaw is ordinarily connected to the fixed jaw and connect the jaws together in
the following manner. In the fixed jaw and at the base or part where the joint pin
is ordinarily situated we make a nearly semi-cylindrical depression crossing the axis
of the clamp. On the base of the movable jaw of the clamp we make a semi-
cylindrical rib or projection of a size and shape suitable for engaging in the
depression in the fixed jaw. The said rib is engaged in the said depression and a
connection of the nature of a joint is thereby formed. A screw pin is passed
through the middle of the jaws as usual the screwed end of the said pin taking into
a screw nut. The jaws being grasped between the head of the screw pin and the
screw nut the jaws can be tightened or relaxed by turning either the head of the
screw pin or the screw nut. Either the head of the pin or the screw nut or both
may be made of a hemi-spherical figure at the side bearing against the jaws; or the
head of the screw and the screw nut may have washers of a hemi-spherical figure
and the jaws may have corresponding concavities in which the hemi-spherical part
of the head of the screw pin and nut or of the washers work. The curved face of
the head of the screw the screw nut and washer has a flat made on it and the
concavity in the jaw has a corresponding figure. The turning of either the screw
or nut as may be desired is thereby prevented. A bow or other spring for forcing
open the jaws when the screw is relaxed is placed preferably near the pin and
crossing the axis of the clamp.
Instead of making a rib on one jaw engage in a recess in the other jaw both jaws
may have semi-cylindrical recesses and a cylindrical pin may engage in the two
recesses and thus form a joint. The said pin prevents motion of one jaw on the
other either longitudinally or laterally. Or two or more short semi-cylindrical
pieces or snugs may be formed on one jaw and engaged in corresponding recesses in
the other.
According to another of our improvements we connect the two jaws by a joint
near their middle and effect their closing and opening by a screw working in the
rear end of the movable jaw. The said screw is at right angles to the axis of the
clamp and its end may either bear on the inner face of the base of the fixed jaw or
against the end of a screw in line with it working in the fixed jaw.
Another of our improvements consists in dispensing with the joint in the last
described clamp and making the jaws engage together by a projection on the inner
face of one taking into a recess in the inner face of the other the jaws being held
together by a ring engaging in a groove around the middle of the clamp.
Another of our improvements consists in connecting the jaws together by a pin
having a head at each end the head at one end being oblong. This pin with its
oblong head foremost is passed through an oblong slot in the middle of the jaws
and turned through a quadrant when it becomes fixed in position.
Although we have only described our improvements as applied to clamps having

page_text: only two jaws one fixed and one movable yet our improvements may be applied
wholly or in part to clamps having two or more movable jaws.
Dated this 27th day of November 1890.
W. T. WHITEMAN,
Agent for the Applicants.
LTIVATION.
Improvements in Clams or Clamps for Lathes.
We CHARLES TAYLOR and GEORGE BENJAMIN TAYLOR both of Bartholomew
Street Birmingham in the County of Warwick Machinists do hereby declare the
nature of our 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 has reference principally to the clams or clamps used in lathes; in
which clams or clamps the get or other waste piece of the article to be turned in the
lathe is held. Such clamps open only to a small angle. Our invention is however
also applicable to clamps generally for lathes.
According to one of our improvements we dispense with the joint by which the
loose jaw is ordinarily connected to the fixed jaw and connect the jaws together in
the following manner.
In the fixed jaw and at the base or part where the joint pin is ordinarily situated
we make a nearly semi-cylindrical depression crossing the axis of the clamp. On
the base of the movable jaw of the clamp we make a semi-cylindrical rib or
projection of a size and shape suitable for engaging in the depression in the fixed
jaw. The said rib is engaged in the said depression, or several ribs or depressions
may be formed on each half engaging with each other, and a connection of the
nature of a joint is thereby formed. A screw pin is passed through the middle of
the jaws as usual the screwed end of the said pin taking into a screw nut.
The
jaws being grasped between the head of the screw pin and the screw nut the jaws
can be tightened or relaxed by turning either the head of the screw pin or the screw
nut. Either the head of the pin or the screw nut or both may be made of a hemi-
spherical figure at the side bearing against the jaws; or the head of the screw and
the screw nut may have washers of a hemi-spherical figure and the jaws may have
corresponding concavities in which the hemi-spherical part of the head of the screw
pin and nut or of the washers work. The curved face of the head of the screw or
the screw nut and washer has a flat made on it and the concavity in the jaw has a
corresponding figure. The turning of either the screw or nut as may be desired is
thereby prevented. A bow or other spring for forcing open the jaws when the
screw is relaxed is placed preferably near the pin and crossing the axis of the.
clamp.
Instead of making a rib in one jaw engage in a recess in the other jaw, both jaws
may have semi-cylindrical recesses and a cylindrical pin may engage in the two
recesses and thus form a joint. The said pin prevents motion of one jaw on the
other longitudinally. Or two or more short cylindrical loose pieces may be used
engaging in corresponding recesses in either half of the clams, preventing motion of
the jaws upon each other both longitudinally and laterally.
According to another of our improvements we connect the two jaws by a joint of
any convenient form near their middle and effect their closing and opening by a
screw working in the rear end of the movable jaw. The said screw is at right
angles to the axis of the clamp and its end may either bear on the inner face of the
base of the fixed jaw or against the end of a screw in line with it and working in
the fixed jaw.
Another of our improvements consists in connecting the jaws together near the
middle of their length by a pin having an oblong shaped head at each end. This
pin is passed through an oblong slot in the middle of the jaws and turned through

page_text: a quadrant when it becomes fixed in position. In this case the jaws are actuated by
pins in the rear as above described.
We will now proceed to describe with reference to the accompanying drawings
the manner in which our invention is to be performed.
Figure 1 represents in longitudinal vertical section, Figure 2 in cross section and
Figure 3 in plan a clam or clamp for a lathe constructed according to one of our
arrangements; Figure 4 represents a plan of the screw nut used with the opening
and closing screw.
The same letters of reference indicate the same parts in Figures 1, 2, 3 and 4.
a is the fixed jaw and b the loose jaw of the clam or clamp between which jaws
the get or waste piece of the article to be turned in the lathe is held. The loose
jaw b is jointed to the fixed jaw a so that it may have a small angular motion for
opening and closing the clamp and releasing and fixing the get or waste piece by
means of the semi-cylindrical ribs c, e on either side the middle portion of the loose
jaw b fitting and turning in semi-cylindrical depressions d in the fixed jaw a. When
the loose jaw b is raised from or lowered upon the fixed jaw a in the manner herein-
after described the ribs c, c of the said loose jaw turn in the depressions d in the
fixed jaw and form a kind of knuckle joint or connection as will be understood by
an examination of Figure 1.
The loose jaw when relaxed is lifted from the fixed jaw by means of the bow
spring e between and crossing the two jaws near their unjointed ends. In the
drawing we have represented the knuckle parts c, d of the joint in combination
with a loose cylindrical pin f made to engage in semi-cylindrical recesses g, g in the
opposed faces of the two jaws as seen in Figure 1. This loose cylindrical pin fis
situated at the middle of the two jaws, that is, between the semi-cylindrical ribs
and depressions c, d of the two jaws. By means of the said pin f the longitudinal
motion of one jaw upon the other jaw is prevented, the loose jaw when it is raised
or lowered working upon the upper half of the said pin.
In place of one loose cylindrical pin f as represented, two or more short loose
cylindrical pins or pieces may be used for forming the joint of the clam, the said
loose pins or pieces being fitted and working in semi-cylindrical recesses in the
opposed faces of the two jaws. By the use of the series of loose pins or pieces last
described the motion of the jaws upon one another both longitudinally and laterally
is prevented.
Although we prefer to combine with the knuckle like joint or connection of the
clam the loose cylindrical pin as described and represented, yet the said knuckle
like joint or connection may be used without a loose cylindrical pin; and instead of
two semi-cylindrical ribs and depressions as described and represented to form the
joint, several short ribs and depressions may be formed on both halves of the clam
and made to interlock.
The opening and closing of the clam is effected by the screw pin h and screw nut i
the jaws a, b being gripped between the head 2 of the pin and the screw nut. The
screwed end of the pin h takes into the screw nut i which nut is prevented from
rotating by means of flats on opposite sides of its inner face (see the separate view
Figure 4) taking into corresponding recesses, in the fixed jaw a. By turning the
head of the screw pin the two jaws may be tightened or relaxed the loose
jaw moving on the joint hereinbefore described the said loose jaw when relaxed
being pressed open by the bow spring e.
The underside of the head of the screw pin h is made of a hemispherical
figure marked ³ and bears or seats itself upon the corresponding shaped seat or
depression 62 on the loose jaw b and the inner face of the screw nut i has also a
hemispherical figure at 2 and bears or seats itself upon the corresponding shaped
seat or depression a² on the fixed jaw a (see Figure 1). When the loose jaw b is
raised or lowered the hemispherical underside of the head of the screw pin h and
the hemispherical inner face of the screw nut i have a slight oscillatory motion
upon their respective seats on the jaws and the breaking of or injury to the screw
pin h is thereby prevented.

page_text: Instead of providing the head of the screw pin and screw nut with the hemi-
spherical parts h³ and washers of the same figures and with or without flats may
be employed; and instead of making the screw nut incapable of rotation it may be
made capable of rotation so that by turning either the head of the screw 'pin' or'
the screw nut the jaws a, b may be tightened or relaxed.
Figure 5 represents in side elevation; Figure 6 in longitudinal section; Figure 7:
in cross section and Figure 8 in plan a clam or clamp for a lathe constructed
according to another arrangement of our invention.
The same letters of reference indicate the same parts in Figures 5, 6, 7 and 8.
k, are the two jaws of the clam having a parallel motion to and from one
another, the said jaws being pressed asunder when released by the bow spring m
between them near their connected ends, the parallelism of the motion of the two
jaws when closing being very accurately preserved by the cross ribs n, n on either
side the middle of the upper jaw k taking into the corresponding depressions p, p in
the lower jaw. The two jaws are connected together by and slide upon the pin q
having an oblong shaped head q2 at each end.
In the two jaws a, b is an oblong slot r through which the pin q is passed. In
passing the ping to its place in the jaws its heads 92, 92 are passed through the
oblong slot and the pin is then turned through a quadrant so as to cause its heads
to cross the slot r and thereby connect the two jaws together.
2"
The two jaws k l are opened and closed by the screw pins s, t at their rear ends
the said pins being in line with one another and working in screw boxes in the said
jaws. By turning one or other of the two pins s, t in the proper direction the two
jaws k, I can be separated from or closed upon one another the said jaws sliding
upon the pin g as they are opened and closed and the ribs n, n working in the
depressions p, p.
One screw pin only may be employed instead of the two pins s, t represented.
In this case the end of the screw pin carried by one of the jaws bears on the inner
face of the other jaw.
Although we have only described and represented our improvements as applied
to clamps having only two jaws, one fixed and one movable, yet our improvements
may be applied wholly or in part to clamps having two or more movable jaws.
Having now particularly described and ascertained the nature of our invention
and the manner in which the same is to be performed we declare that we claim as
our invention of "Improvements in clams or clamps for lathes ":-
:
First Constructing the joint of the jaws of the clam or clamp of one or of a
series of semi-cylindrical ribs or projections on the rear end of the inner face of
one jaw engaging with corresponding semi-cylindrical depressions in the base of the
rear end of the other jaw substantially as herein before described and illustrated in
Figures 1, 2 and 3 of the accompanying drawings.
Secondly-Constructing the joint of the jaws of the clam or clamp of one or
more loose cylindrical pins or pieces at their rear ends taking into semi-cylindrical
depressions in the opposed faces of the jaws; or the combination of one or more of
the loose cylindrical pins or pieces with semi-cylindrical engaging ribs and
depressions substantially as hereinbefore described and illustrated in Figures 1, 2
and 3 of the accompanying drawings.
Thirdly Opening and closing the clam or clamp by means of a screw pin and
nut the head of the screw pin or screw nut or both having a hemi-spherical figure
for taking a bearing against a corresponding seat or concavity in the jaw; or
providing the head of the screw pin or screw nut with hemispherical washers for
the same purpose substantially as herein before described and illustrated in
Figures 1, 2, 3 and 4 of the accompanying drawings, whether the head of the screw
pin or screw nut or the washers have flats for preventing their rotation or are
without flats.
:-
Fourthly Connecting the jaws of the clam or clamp together by means of a pin
having an oblong head at each end passed through an oblong slot in the jaws and

page_text: the combination therewith of the ribs on one jaw taking into depressions in the
other jaw substantially as hereinbefore described and illustrated in Figures 5, 6, 7
and 8 of the accompanying drawings.
Fifthly-Opening and closing the jaws of the clam or clamp by means of a screw
pin or pins situated at the rear of the joint on which the jaws work substantially as.
hereinbefore described and illustrated in Figures 5, 6 and 7.
Sixthly:-The adaptation to the clams or clamps referred to in the prior claims of
a bow spring for opening or separating when relaxed the jaws of the said clams or
clamps as hereinbefore described and illustrated in the accompanying drawings.
Dated the 30th day of July 1891.
CHARLES TAYLOR.
GEORGE BENJAMIN TAYLOR.