Improvements in Hat-block Chucks.
Year: 1899

page_text: Date of Application, 2nd May, 1899-Accepted, 17th June, 1899
Improvements in Hat-block Chucks.
I, GEORGE FREDERICK LARKIN, of No. 187, Broad Street, in the City of Newark,
County of Essex and State of New Jersey, United States of America. Manu-
facturer, 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 has reference to certain new and useful improvements in hat-
block chucks; and the invention has for its principal object to provide a novel
construction of hat-block chuck which can be readily secured in position on the
end of a lathe-spindle and can be easily detached therefrom, while the spindle
is revolving.
This invention has for a further object to provide a novel and effectively oper-
ating clutch-mechanism for readily securing the hat-block in its operative position
on the lathe. With these several objects in view, the invention consists, generally,
in the novel construction of hat-block chuck hereinafter described; and. furthermore,
my invention consists in such novel arrangements and combinations of parts and
the details of the construction thereof, all of which will be more fully set forth
in the accompanying specification, and finally embodied in the clauses of the
claim.
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The invention is clearly illustrated in the accompanying drawings, in which:-
Figure is an elevation of my novel construction of hat-block chuck in its
operative position on the lathe-spindle, the lathe and its spindle being broken
away, and the hat-block being represented in part in vertical section.
Figure 2 is an end view of the several parts illustrated in said Figure 1, with
the hat-block detached.
Figure 3 is a vertical cross section. taken on line - in said Figure 1:
Figure 4 is a longitudinal vertical section of the hat-block chuck, with the hat-
block detached; and Figure 5 is a vertical cross section, on an enlarged scale,
of the lathe-spindle, the chuck-collar, and the chuck-jaws. said view illustrating
in detail the pivotal connection between each chuck-jaw and the chuck-collar.
Figure 6 is a perspective view of one of the chuck-jaws.
Similar letters of reference are employed in all of the said above described
views, to indicate corresponding parts.
In said drawings, 6 indicates the hat-block, which is provided within its rear
face with an annular recess b' to provide a central hub & substantially as illus-
trated in Figure 1.
Rotatively arranged in the usual form of bearing a of any of the well known
constructions of lathe is the lathe-spindle a', which, as will be seen more especially
from Figure 4. is provided with a screw-threaded end a³ for receiving the hat-
block chuck, as will be set forth more in detail in the following description.
Secured upon the upper portion of the bearing a, by means of bolts or screws a³,
or in any other well known manner, is a plate a' having a forwardly extending
arm which is bifurcated at its free end by having a pair of perforated bear-

page_text: ing-portions in which there is a più or bolt a to he used for the purposes
herein-after set forth.
The hat-block chuck consists, essentially, of a screw-threaded hub c having
two or more. (preferably three, as here illustrated.) forwardly extending arms
or posts to the free ends of which is secured, by means of screws d', or in any
other suitable manner, a chuck-head of which is provided with a forwardly
extending and centrally arranged bearing pin which extends into a correspond-
ingly arranged socket in the central hub 72 of the hat-block, when the latter is
secured in position, as will be presently set forth.
In the peripheral surface of the hub c. I have arranged a suitable number
of holes or sockets . preferably three in number, as indicated in Figure 5, in
ach of which is operatively arranged the ball-shaped end of a post at the
rear end of each chuck-jaw e, in such a manner, that each jaw has a free aseil-
latory motion, when in its operative position in the hat-block chuck proper.
The construction of each chuck-jaw is illustrated more particularly in Figure 6,
the forward end of each jaw being flattened out, as shown, and curved on
its under side to correspond with the cylindrical surface of the hub 3 of the
but-block, or approximately so. Each jaw has in engagement with its under
side a suitable spring, as f, which is operatively secured at one end to the hub e
and presses against the jaw, so that the normal tendency of each jaw is to be
forced outwardly or in a direction away from the longitudinal and central axis
of the lathe-spindle, as will be clearly evident from an inspection of Figure 4.
The forward end-portions of said chuck-jaws e extend into and through corre
spondingly arranged openings d in the chuck-head d, said openings being sulli-
ciently large to allow of an outward radial motion of the forward ends of said
jaw. To limit the excess lateral motion of the forward ends of the jaws c. each
jaw has a hole directly in alignment with centrally arranged pins which are
driven into the peripheral edge of the head d and down through the openings d'
into the body of said head, as clearly illustrated in Figures 2 and 4. Said
pins are passed through the holes in the respective chuck-jaws c, the dinmeter
of each hole being slightly greater than the diameter of the pin, to permit
of a limited Interal motion of each jaw e, whereby the free end of each jaw will
readily accommodate itself to any inequalities in the cylindrical surface of the
hub of the hat-block b, when brought in operative grasping position with the
hub.
Slidably arranged on the several chuck-jaws is a collar y having a central
opening of an interior diameter approximately equal to or a trifle larger than
the diameter of a circle passing through the outer surfaces of the radially arranged
jaws, so that any forward motion of said collar will depress said jaws c and
bring their free ends in operative clamping or holding relation with the cylin-
drical surface of the hub of the blook, as will be clearly understood.
Said collar is provided with a circumferential groove gland operatively
fitted in said groove is a bearing-block having the are-shaped parts which
fit in the circumferential groove g' to more readily retain the said block in
its operative position on the collar g. To prevent any lateral displacement of
said block, the same is operatively arranged between a pair of guides a extend-
ing longitudinally from said plate a substantially as illustrated. Said block
is provided at the top with oppositely projecting arms having gear-teeth 41.
whereby a suitable rack is provided. Pivotally arranged on the pin or bolt a
herein above mentioned is the hub of an operating lever i, said hub being
provided with gear-teeth, which are in operative mesh with the rack-teeth A
From an inspection of Figures I and 4, it will be evident, that by throwing the
lover forward the collar will be moved toward the bearing a of the lathe, and
the springs will cause the jaws to become relaxed from their gripping or
holding relation with the hub of the hat-block, but a backward movement of
the lever causes the collar g to slide forward, whereby the ends of the jaws are
brought in grasping or holding relation with the hub of the hat-block.

page_text: Normally, when the machine is at rest, the lever is in its forward position
and the block can be placed against the head d. The lever is then thrown
backward, thereby driving the collar g forward and forcing the jaws e firmly
against the hub of the hat-block, whereby the latter is held in its operative
position.
From the above description, it will be seen, that I have devised a simple and
operative mechanism for attaching a hat-block in its operative relation upon the
lathe-spindle, or for removing it therefrom, while the spindle is revolving.
I am fully aware that changes may be made in the various arrangements and
combinations of the parts, as well as in the details of the construction thereof,
without departing from the scope of my present invention, as for instance, the
hat-block chuck proper may be differently secured in position upon the end of
the lathe-spindle, and the chuck-head may be variously connected with the
ends of the arms or posts e of the chuck-collar e: also, the centering pin of said
head may be dispensed with, if desired. Hence, 1 do not limit my invention
to the exact arrangements and combinations of the several parts herein described
and illustrated.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is
1. The combination, with a bearing and its lathe-spindle, of a hat-block chuck,
comprising spring-actuated chuck-jaws, a collar sliding circumferentially on
said jaws, means connected with said bearing for preventing lateral displace-
ment of said collar, a rack on said collar, and a toothed operating lever in engage-
ment with said rack, whereby said jaws may be actuated to cause them to grasp
the hub of a hat-block, substantially as and for the purposes set forth.
2. The combination, with a bearing and its lathe-spindle, of a hat-block chuck
comprising spring-actuated chuck-jaws, a collar sliding circumferentially on said
jaws, a circumferential groove in said collar, a block having arc-shaped parts
fitted in said groove, means connected with said bearing for preventing lateral
displacement of said collar, a rack on said block whereby said jaws may he
actuated to cause them to grasp the hub of a hat-block, substantially as and for
the purposes set forth.
3. The combination, with a bearing and its lathe-spindle, of a hat-block chuck,
comprising a hub. forwardly extending arms or posts on said hub, a chuck-
head on said arms or posts having openings, spring-actuated chuck-jaws on said
hub having their free ends extending into and through said openings in the
chuck-head. a collar sliding circumferentially on said jaws, and means by which
said jaws may be actuated to cause them to grasp the hub of a hat-block, and
means connected with said bearing and said jaw-actuating means to retain the
same in its operative engagement with said collar, substantially as and for the
purposes set forth.
4. The combination, with a lathe-spindle, of a hat-block chuck, comprising
a hub, forwardly extending arms or posts on said hub, a chuck-head on said
arms or posts having openings, spring-actuated chuck-jaws on said hub having
their free ends extending into and through said openings in the chuck-
head, a collar sliding circumferentially on said jaws, a circumferential groovo
in said collar, a block having arc-shaped parts fitted in said groove, a rack on
said block, and a toothed operating lever in engagement with said block whereby
said jaws may be actuated to grasp the hub of a hat-block. substantially as and
for the purposes set forth.
5. The combination, with a lathe-spindle, of a hat-block chuck, comprising a
hub, forwardly extending arms or posts on said hub, a chuck-head on said arms
or posts having openings, spring-actuated chuck-jaws on said hub having their
free ends extending into and through said openings in the chuck-head, pins in
said openings passing through perforations in said chuck-jaws to prevent lateral

page_text: movement, a collar sliding circumferentially on said jaws, and means whereby
said jaws may be actuated to cause them to grasp the hub of a hat-block, sub-
stantially as and for the purposes set forth.
6. The combination, with a lathe-spindle, of a hat-block chuck, comprising a
hub having sockets, chuck-jaws having ball-posts in said sockets, whereby said
jaws have an oscillatory motion, a collar sliding circumferentially on said jaws,
means to limit the lateral motion of said jaws, and means by which said jaws
may be actuated to cause them to grasp the hub of a hat-block chuck, substan-
tially as and for the purposes set forth.
7. The combination, with a Inthe spindle, of a hat-block chuck, comprising a
hub having sockets, forwardly extending arms or posts on said hub, a chuck-
head on said arms or posts having openings, chuch-jaws having ball-posts in said
sockets, whereby said jaws have an oscillatory motion, and said jaws having their
free ends extending into and through said openings in the chuck-head, a collar
sliding circumferentially on said jaws, and means by which said jaws may he
actuated to cause them to grasp the hub of a hat-block, substantially as and for
the purposes set forth.
GEORGE FREDERICK LARKIN.
Haseltine, Lake & Co..
45, Southampton Buildings, London, W.C., Agents for the Applicant.