Year: 1898

page_text: Complete Specification Left, 22nd Apr., 1899-Accepted, 24th June, 1899
I, HENRY HARRIS LAKE, of the Firm of Haseltine, Lake & Co., Patent Agents,
45, Southampton Buildings, in the County of Middlesex, do hereby declare the
nature of this invention to be as follows:-
_
My invention relates to an improved automatic dental pluggers.
The plugger constructed according to my said invention comprises a plugger-rod
surrounded by a cylindrical handle or case, a spring actuated plunger-hammer also
enclosed within said handle or case and surrounding the plugger-rod. The plugger-
rod has a shoulder, enlargement or projection formed thereon and the hammer
is provided with an interior projection to engage, after a preliminary movement,
with the shoulder or projection of the plugger-rod. A spring-latch is attached
to the plugger-rod and adapted to engage directly with the inner wall of the sur-
rounding hammer.
As the said plugger-rod is pushed upwards in the handle by pressure upon the
object to be operated upon, the spring-latch engaging said hammer carries it
upward against, and causes the compression of the spring adapted to actuate it.
The said spring-latch is provided with an inclined surface adapted to contact with
a projection or member connected with the surrounding handle to cause the release
of the hammer after it has forced the same against and caused the compression
of its actuating spring, thereby, permitting said hammer to return and impinge
the plugger-rod with a sharp impact.
I provide suitable means for limiting the range of the spring actuated movement
of the hammer and independent spring means for carrying the plugger-rod with its
spring-latch beyond the limit of movement of the hammer to secure the re-engage-
ment with it, of said spring-latch, and convenient and adequate means for adjusting
the degree of tension or compression of the spring for actuating the hammer. The said
adjusting means consists of a screw extending longitudinally into one end of the
cylindrical handle and rigid with the cap rotatable thereon and a threaded nut
or collar adapted to fit the said screw and provided with projections extending into
diametrically opposite longitudinal slots in the surrounding-handle so that the
turning of the cap forces the collar toward or away from the hammer to cause the
compression or permit the extension of a spiral spring located between the said
collar and the hammer.
The arrangement of the hammer and plugger-rod above described enables me to
provide a plugger-rod protruding from both ends of the surrounding-handle, in
which case the screw above mentioned for adjusting the tension of the spring for
actuating the hammer may be in form of an exteriorly threaded tube centrally

page_text: located in the end of said cylindrical-handle and adapted to permit the exten-
sion of the plugger-rod through it and the cap with which it is rigid.
Dated this 23rd day of July 1898.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.
I, HENRY HARRIS LAKE, of the Firm of Haseltine, Lake & Co., Patent Agents,
45, Southampton Buildings, in the County of Middlesex, 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 dental pluggers. My object being to
provide simple and efficient means for actuating the hammer to impinge the spindle,
improve means for adjusting the spring actuating the hammer, and improvements
in details of construction, especially adapted to uulize the maximum interior space
of the cylinder for the accommodation of the hammer so that the size and etti-
ciency of the hammer may be increased without increasing the size of the cylinder.
I obtain these objects by the mechanism shown in the accompanying drawings
of which Fig. 1 is a longitudinal section of my device, except that the spindie
and latch are in perspective. Fig. 2 is a detail view in perspective of the upper
portion of the cylinder. Fig. 3 is a detail view in perspective of the lower end
piece 4.
Referring to the drawings, 1 indicates the casing or surrounding cylinder;
2, the spindle movable longitudinally within and protruding at each end; 3, the
hammer surrounding the spindle and surrounded by the cylinder and longitudi-
nally movable therein.
Into the lower end of the cylinder 1, is threaded the end piece 4 through which
protrudes the spindle. At the upper end of said cylinder is secured the end
piece 5, through which the spindle may also protrude. The end piece 5 is provided
with the circumferential projection or shoulder 6, adapted to engage with the
circumferential projection or bent-over edge 7, of the upper wall of the cylinder.
The cylinder is split or longitudinally slotted at its upper end as shown in Fig. 2,
so that it will spread sufficiently to permit of snapping the edge 7 over the said
projection 6. Extending downward from the projection is a threaded exten-
sion 8 of the piece 5, adapted to carry a threaded nut 9, with projections extending
into the longitudinal slots 10 of the cylinder so that as the piece 5 is turned in
the cylinder the nut will ride up and down to secure the required tension of the
spiral spring 11 which is located within the cylinder and intermediate the nut 9
and hammer 3, one end of said spring bearing against the hammer and the other
end against the nut.
Toward the lower end of spindle 2 is a recess 12, into which is secured the spring
latch 13, provided near its free end with the projection 14, adapted to engage
with the lower interior edge of the surrounding hammer 3 and extending from
the projection 14 to the free end of the latch is a further projection, having an
inclined surface 15 adapted to engage with an antifriction roller 16 secured in a
slot in the surrounding piece 4. As the spindle is pushed into the cylinder the
latch carried thereon having engaged the hammer as shown in Fig. 1, the inclined
surface of the latch and the antifriction roller 16 co-operate to compress the latch
causing it to release the hammer after it has been moved the required distance;
the hammer thereupon responding to the actuation of spring 11, returns to impact

page_text: the spindle in the manner hereinafter described. Upon the upper part of the
hammer is a plug or projection 17, adapted to encounter a projection 18 on the
spindle. The plug 17 is threaded into the top of hammer and capable of move
ment therein for the purpose of adjusting the length of stroke of the hammer, a
suitable lock nut 21 is employed for securing the plug after adjustment. The
projection 18 is a pin threaded through the spindle and is inserted into the spindle
through an aperture 23 in the hammer, while the spindle is surrounded by the
hammer. In case the spindle should not protrude through the end piece 5 but
should end substantially at the point where the projection 18 is shown, the plug
or projection 17 may encounter the top of said spindle in the downward movement
of said hammer as above described giving the necessary impact to the spindle.
After the impact of the hammer upon the spindle its downward movement is
finally stopped by the engagement of the lower end of the hammer with the top of
piece 4.
The spring 19, which surrounds the spindle within the piece 4 and
operates between suitable projections on the spindle and surrounding piece, serves
to carry the spindle beyond the movement of the hammer to secure the re-engage-
ment of the latch 13 with the hammer. The tip 22 serves as a guide for the
spindle as well as a limit to its spring actuated movement.
The feature of so arranging the spring latch that its trip projection shall occupy
and move in a recess in the end portion of the case and be depressed by means
seated in such recess, is an important one, for the reason that the latch and its
depressing device do not in any way encroach upon the space within the case,
but leave said space free for the reception of the hammer which can extend down
to the end piece. In this way, without in any way increasing the size of the case,
I am enabled to materially increase the size and weight of the hammer.
Casing 24 of the hard rubber or other suitable material adapted to fit snugly
around the cylinder 1 being held in place by the caps 25 and 26 of similar material
which are threaded on the end pieces 4 and 5 respectively as shown.
As above stated, if it is only desired to have spindle protrude from one end of
the cylinder, it may terminate at a point substantially where the projection 18 is
shown, the plug 17 may then be solid and adapted to impact directly upon the
top of the spindle. The end piece 5 may also be solid and may terminate slightly
above the shoulder 6 as indicated by dotted line 20 in Fig. 1.
A special advantage of the bent-over circumferential edge 7 of the cylinder is
that when it is snapped over the said projection 6 of end piece 5 as shown in
Fig. 1 and the hard rubber cap 26 is slipped over the cylinder the latter is thereby
effectually prevented from spreading at the split end and the consequent accidental
disengagement of the end piece 5 is prevented.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, as communicated to me by my
foreign correspondent, I declare that what I claim is:-
1. In a dental plugger, the combination of a spindle, a hammer surrounding
the spindle, and a cylinder or case surrounding the hammer and having an interior
recess at one end portion, of a spring latch secured to the said spindle in a recess
thereof and provided with a projection for engagement with the hammer and also
with a further projection arranged to occupy and move in the said recess in the
surrounding case and means in said recess to co-act with said last named projection
and retract said latch from its engagement with the hammer at the proper time,
together with a spring means for actuating the spindle to secure the re-engage-
ment of said latch and hammer, substantially as specified.
2. In a dental plugger, the combination of a spindle, a hammer surrounding
the spindle, and a cylinder or case surrounding the hammer and having an
interior recess at one end portion, of a spring latch secured to the said spindle in
a recess thereof and provided with a projection for engagement with the hammer
and also with a further projection arranged to occupy and move in the said recess
of the surrounding case and means in said recess to co-act with said last named

page_text: projection and retract said latch from its engagement with the hammer at the
proper time, together with spring means for actuating the spindle to secure the
re-engagement of said latch and hammer, spring means for actuating said hammer,
and means for manually adjusting the tension of the same, substantially as
specified.
3. In a dental plugger, the combination of a spindle, a hammer surrounding
the spindle, and an inclosing case, means for actuating and tripping the said
hammer, and a plug adjustably secured in the end of the hammer, and forming
an adjustable contact between the hammer and spindle whereby the length of the
hammer stroke may be regulated, substantially as specified.
4. In a dental plugger the combination of a cylinder longitudinally slotted at
one end and provided with an interior circumferential projection or recess, an end
piece adapted to be inserted in said cylinder having a co operating circumferential
projection or recess to engage with said circumferential projection or recess of
the cylinder and an outer case surrounding the cylinder to prevent its spreading,
substantially as described.
5. In a dental plugger, the combination of a hammer, a spindle, and a case,
having an interior. recess at one end portion, a spring latch connected with the
said spindle and adapted to engage with the said hammer, said latch also having a
projection adapted to occupy and move in the said recess, and an antifriction
roller seated in the recess as means for depressing said latch at the proper time
to free it from engagement with the said hammer.
6: In a dental plugger, the combination of a cylinder longitudinally slotted at
one end, an end piece adapted to be inserted in said cylinder, a circumferential
groove and shoulder connection between said cylinder and end piece, and an outer
member adapted to surround the cylinder to prevent its spreading, substantially
as described.
1000
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.