Year: 1888

page_text: We, BENIJAH SMITH BYRNFS, D D.S, and WILLIAM MACON SMITH, Attorney-at-
Law, both of Memphis, in the County of Shelby and State of Tennessee, United States
of America, 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
Our invention consists of an improved dental plugger, in the means for imparting
and controlling blows to the tool holder; in the means for guiding the hammer; also
the form of the rear stiffening bracket and certain other features as will herein-after be
fully set forth
We now proceed to describe our invention, reference being had to the accompanying
drawings and the figures and letters marked thereon.
Figure 1, is a longitudinal sectional elevation of our dental plugger showing the
hammer grooved and partially raised.
Fig. 2 is a similar view showing the hammer in its lowermost position, the position
it occupies when delivering a blow. Fig. 3, is a longitudinal sectional elevation
showing the plugger out of gear, and the guide ribs in the casing. Fig 4 is a perspec-
tive view of the hammer removed from the casing and showing side grooves. Fig. 5
1s a perspective view of the rotating spindle and cam for lifting the hammer. Fig. 6
18 a vertical sectional view of the tool holder, showing position of tool shank, stop-pin
and spring. Fig. 7 is a perspective view of the flexible hand piece and end stiffening
clamp.
A, represents the main casing formed upon the inside with longitudinal projecting
ribs, a, a, that project into the grooves b, b, in the sides of the hammer B. The lower
end of the casing A, is closed by the screw tip C, in which is held the shank D, into
which the plugging too! E or other instrument is screwed as shown in Figs 1, 2 and 3
The shank D, is held normally elevated in the tip C, by the light coiled graduating
spring F, so that the upper end of the said shank will bo in range of the stroke of the
hammer B, which stroke is produced by the cam B1 (forming a part of the hammer)
the rotary cam G, spindle H, and coil spring J, held in the casing A, above the
hammer.

page_text: The cam B is formed to fit closely the inner face of the upper end of hammer B.
and is held in place by a bolt a¹ that passes through a perforation a³ formed in said
casing and through a similar perforation in cam B¹, thus holding the parts securely
in place; however other suitable means may be used to hold said parts in
place.
The centre of cam B' is formed with opening for the free passage of the spindle H
A similar cam G is secured to the inner end of spindle H. and its curved edge
is adapted to work against the curved edge of cam B.
The spindle H, is adapted to be revolved by any suitable motor attached to its
outer end by a tip d or other suitable means The revolution of the spindle H, and
cam G by contact with cam B¹, lifts the hammer B until the toes of the cams pass
each other This lifting motion compresses the spring J (that encloses the spindle H,)
and when the toe of the rotary eam G, passes the toe of the cam B₁ the spring J reacts
and forces the hammer B, and cam B' downward causing the hammer to deliver a blow
upon the inner end of shank D forcing the shank D and instrument E outward against
the tension of the light graduating spring F which (when free reacts and lifts the shank
and instrument for another blow. The shank D is free to move longitudinally in the
tip C, until it lifts the hammer B, so that any overpressure upon the instrument E,
will lift the shank nearer the hammer B and thus diminish the force of the blow of the
hammer down to the lightest perceptible touch
By this constuction not only is all danger of injury to the patient obviated but the
most delicate and sensitive nerves will be toned down and the teeth filled by the
delicacy and fineness of the touch of instrument E, as the blows are diminished in a
direct ratio to the pressure of the instrument upon the teeth The delicacy and fine-
ness of this movement is further controlled or stopped altogether by a stop-pin a that
1s inserted horizontally through a pertoration at in the tip piece C and extends through
into a slot a cut in the side of shank D whereby when the pin a³ is pressed inward
by the thumb or finger of the operator the shank D is held to its inward limit
raising the hammer B and preventing its movement by throwing the cams G and B¹
out of contact.
Pin a³ 18 held in its normal position by the free end of a small volute spring απ
secured to the inner end of the tip-piece a notch or recess 63 is cut in pin a to
receive the free end of spring a by means of which said pin a³ is held with its inner end
inserted in the slot a forming a stop to prevent the turning of shank D
The tension of the spring J may be increased or diminished as the force of the
hammer blows are required, by a screw-threaded adjustable press plate K or other
suitable means. The adjustable plate K is formed with side screw-threaded projections m
which reach through slots m¹ in the casing A to engage with the internal screw-threads
of the sleeve L. The case A is off set at c, to receive the sleeve Land said sleeve is held
in place by the cap or top plate M in which the outer end of the spindle H takes it's
bearings, the same being prevented from longitudinal movement by the collar c and
the top d.
The outer end of the hand piece N is formed with an extended grip frame or
bracket O constructed with hollow shank g to which is secured curved projecting wires h
that extend longitudinally outward and their outer faces or terminal ends are bent
outward at right angles, to permit of the introduction of the drive shaft around which
1s tightly sprung the casing P and around which is the grip frame O.
Clamps hold it in place and prevent breaking at the screw joint or connection.
It also forms a hand stop-piece for the operator in manipulating the plugger.
By this invention a cheap, durable and delicate stroke plugger is produced, that may
be thrown out and in gear without stopping; can be held out of gear by light finger
pressure at the will of the operator, and the hammer stroke tapered or fined down to
a delicate touch, to prevent injury to the patient's teeth or cause undue nervous
excitement.
It permits the operator to make a perfect and compact filling. It stops and picks up
the gold foil on the end of the instrument-E; the operator moves tho, foil, to the
hollow tooth fills, burnishes ; levels, and tapers, it down to an even surface with the

page_text: teeth either by the drawing or pushing movement, and by our construction, the
edges of the teeth may be chamfered or rubbed off and the surface left
smooth.
Having now particularly described and ascertained the nature of our said Inven-
tion, and in what manner the same is to be performed we declare that what we
claim 18:
1. A dental plugger consisting of a casing enclosing a grooved hammer, a coiled
spring and suitable adjustments, curved cams within the hammer, a central spindle, a
hollow tip, a slotted shank and spring loosely held within said tip; an adjustable set
screw adapted to contact with said shank, and a volute spring held within said tip,
substantially as and for the purpose set forth.
2. A dental plugger consisting of a casing enclosing a grooved hammer adapted to
contact with guides projecting into the grooves, an adjustable spring within said casing
and above the hammer A spindle and curved cams secured to said hammer,
a hollow tip, a coiled spring, sliding shank, and volute spring, secured within said tip
and an adjustable horizontal set pin, substantially as set forth
3. A dental plugger consisting of a casing enclosing a cylindrical grooved hammer
it's open end secured to a centrally perforated cam, a spindle secured to a cam at its
inner end within said hammer, and extending through said perforated cam, a hollow
tip having side perforations and enclosing slotted shank, coiled spring, and a volute
spring it's free end adapted to contact with a side pin projecting into the slot in said
shank, and means for connecting said tip with the casing, substantially as set
forth
4. An end stiffening grip for flexible hand piece of dental pluggers, consisting of a
hollow shank with longitudinal curved projections extending over and enclosing the
connected drive shaft casing, substantially as and for the purpose set forth.
Dated this 6th day of June 1888.
Agents
HORN & SON,
on behalf of the Applicants.