Improvements in Dental Chairs
Year: 1895

page_text: Date of Application, 30th Apr, 1895-4ccepted, 1st June 1995
Improvements in Dental Chairs
1, ARIHUR WILLIAM BROWNL, of Punces Bay, in the County of Richmond,
and State of New York, United States of America, Manufacturer, do hereby
declare the nature of this invention and in what manner the same is to be
performed to be particularly debed and ascertained in and by the following
statement
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My invention relates to certain improvements, as hereinafter claimed, applicable
to portable dental chairs constructed in sections which may readily be assembled
for use and disconnected and compactly packed for convenient tran portation
In the accompanying drawings which represent a suitable embodiment of my
improvements,
Fig 1 is a rear and side perspective view of the chair in position for use, with
the box which serves for packing the chan arranged as a foot board or platform
for the chair and support for the foot rest thereof
Fig 2 is a front and side perspective view on a smaller scale than Fig 1, and with
a changed adjustment of parts
Fig 3 is a view substantiall, corresponding with Fig 2 except that the box,
foot rest, seat and bick pad arc omitted
Fig 4 is a view in perspective on a reduced scale of the combined packing box,
foot board or platform and foot rest support, with the lid raised to show how the
box is adapted to support the foot rest
Figs 5 to 9 inclusive are views showing details of construction, Fig 5 being
a longitudinal section through one of the legs and its connecting socket Fig 6
a plan view of devices for supporting the seat Fig 7 a front elevation of the pad,
block, carrier, and cartier rod of the head rest Fig 8 a side elevation of the
same, with the vertically adjustable head rest supporting rod, and means by which
the head rest cier rod is adjustably connected with the supporting rod
Fig 9a view in perspective showing, separately, parts for securing the frame bar
in its position of adjustment
and
A frame bar or main section A of the chain is adjustibly supported by suitable
leg, and has adjustably connected with it in appropriate seat and suitable back
and head rest pad- Ihre supporting legs and provided, and the rear one 14
composed of an upper section B and a lower section B' adjustably connected with
the upper section and terminating at its lower end in a cross foot piece B' having
feet or bearing points bbit its opposite ends The leg section B has jointed
connection at its upper end with the frame bar A A pivot e passing through
forcks c c of the leg and through lugs CC₁of the frame bar serves to make
proper connection Two diverging front leg, D D are detachably connected with
the frame bai by way of the rear log Ihreaded sockets d d of the leg section B
erve to connect the front legs, the upper ends of which are threaded to screw into
the sockets
An arm C serving to adjust the inclination of the frame bar A. and maintain it
in its position of adjustment, is jointed to the frame bar above the jointed con-
nection of the legs with this bai This adjusting aim is jointed at its upper end
to lugs or short arms a a of the frame bar by a pivot a passing through these lugs
and through the forked end of the adjusting arm At its lower end the frame
bar adjusting arm passe through a ocket or loose bearing in the rear leg adjacent
to the lower or rear end of the upper section B of this leg That portion of the

page_text: adjusting arm which is adapted to slide in the bearing socket in the rear leg is
flattened on one side to adapt it to be securely clamped in the position desired by
means of a clamp screw b³ working in the rear leg section B and operated by a
treadle like foot lever D¹ A set screw d¹ serves to lock the clamp screw to the
foot lever, and lugs d d on the rear leg and on the level serve to limit movement
of the lever when actuated to operate the clamp to release the adjusting arm
A shoulder or fixed collar a³ and a detachably secured collar a³ on the adjusting
arm serve to limit its sliding or endwise movement in the bearing socket of the
rear leg in adjusting the inclination of the frame bar by rocking it about its
pivotal connection with the supporting legs The lower section of the rear leg 15
detachably connected with the upper section thereof and adapted to be turned so
as to properly adjust the bearing feet b b to ensure a firm support of the chair upon
an uneven floor To provide for the attachment and turning movement of the
lower suction of the leg it is screw threaded at its upper end and engaged with
threaded socket B at the lower end of the upper section of the leg
It will be seen that by adjustment of the adjusting arm the inclination of the
frame bar may be varied as desired, this bat rocking about its jointed connection
with the legs, and that the adjusting bar may easily and quickly be clamped and
unclamped by actuation of the clamp lever by the foot It will further be seen
that the front legs may quickly be detached, the reat leg sections disconnected,
and the upper section of the ear leg and the adjusting arm folded up to the
fran e bar, thus providing for the compact packing of the parts for convenient
ti insportation
The upper section of the rear leg is shown as longitudinally ribbed or flanged-
that is made U shape in cross-section, to impart to it desired strength without
unnecessary weight, and the main section or frame bai A is formed with ribs of
flanges extending longitudinally thereof at its back
A seat supporting arm or bracket E is adjustable up and down the frame bar A
and adapted to be locked thereto to locate the seat at any desired height Tho
adjustable seat supporting arm is shown as fitted to slide up and down the frame
bar on guide-ways e e of this bar which with the frame bar extend below as well
as above the point of pivotal support of this bar hy the supporting legs
A row
of holes extends lengthwise of the fiame bar, and a stop pin el adapted to engage
the desired one of these holes beneath the slide E which connects the se it
supporting arm with the frame bar, serves to uphold this arm in its position of
adjustment At its front or outer end the seat supporting aim is provided with
two projections or short aims F F extending literally thereto in oppo ite
directions These side projections FF having upwardly extending lugs ff at
their outer extremities and inside and near each of these lugs there is a socket on
bearing formed to receive the inner end of two seit attaching rods F, one rod
bong fitted to turn in each bearing socket The attaching rods are exactly alike,
cach being bent at its opposite ends in opposite directions so is to constituto
juvoting ends f', the one projecting upwardly and the other downwardly, when
the 1ods are in use The sent proper (r consists of a piece of carpet, canvis o
equivalent flexible material suitably secured at its ends to stretcher bars G'G'
each of which is provided underneath and midway its length with a socket
or bering These sockets receive the outer pivoting ends of the scat attaching
rods
1
It will be seen that the seat attaching rods may readily be pivotally fitted in
then bearing sockets in the seat supporting aim, and the seat stretcher bars then
pivotally adjusted to the outer end of the attaching rods, after which the
backward swing of the rods into contact with the lugs ff spreads out the flexible
seat and propeily stretches it As will be seen by reference to Fig 6 when the
attaching rods are swung back until then further movement is arrested by then
contact with the stop lugs f, the outer ends of the attaching rods pivotally
connecting with the seat stretcher bars extend back of a line drawn centrally
through the bearing sockets for the inner ends of the attaching rods, and the
stretching strain on the flexible material of the seat acts to prevent that slight

page_text: spreading apart of the stretcher bats which would be required to admit of
forward swing of the attaching rods The weight of a person upon the seat
increases resistance to the forward swing or folding toward each other of the
attaching rods To positively prevent accidental forward swing of the attaching
rods a suitable securing device, such as the staple-like rod 7, may be employed
The ends of this securing rod 9 are detachably engaged with sockets in the side
projections of the seat supporting arm in advance of the attaching rods, as will
readily be understood It will be seen that by extending the frame bar below the
point of pivotal connection of the legs therewith the sent may be adjusted to a
Verv low position
A back pad carrier H is adjustable up and down the frame bar A and adapted
to be locked thereto to secure the pad at the height desired This pad cauer H
Is shown as provided with two sets of guide way lugs hhhh, at and above its
lower end, having sliding engagement with the guide ways ee of the fame bar
A clamp consi ting of a screw having an operating handle H' serves to lock the
pad carrier to the frame bor in the desired position At opposite sides of its upper
end the pid carrier is provided with bearing sickets H2 H2, to receive the bent
pivoting ends of two pid attaching 1ods II which are duplicates of each other
and similar to the seat attaching rods F1 F1 except as to dimensions each pad
attaching rod being bent at right angles to its main len_th at its opposite ends to
constitute pivoting ends The back pad I of suitable flexible material is
att chid at its ends to stretcher bars 12 12 provided like the seat stretcher birs,
with socket bearings for the outer ends of the swinging pad attaching rods When
swung out into operative position the pad ttaching rods bear downward upon side
lugs or short lateral projections ²² of the pad carrier
An end wise movable head rest supporting rod J is fitted to slide up and down
and tuin in a socket or bearing J' of the fiame bir A, at the back thereof and a
suitable clamp, such as a pinch screw provided with the handle I, serves to lock
the rod in its position of adjustment Beneath its bearing the rod J works
between the strengthening longitudinal ribs or flanges at the back of the fi ime
bar At its upper end the supporting rod terminate in a head or enlugement K
of substantially circular or disk form A clamp bolt K' having a head k at one
end, and crew threaded at its opposite end, has its threaded end pissed through a
central opening in the head K of the supporting rod I A spline and groove
connection between the screw bolt and supporting 1od head pievent turning of
the bolt in this head A clamp handle having screw-threaded connection with
the bolt serves to move it endwise in the supporting rod head The clamp bolt
pa ses centrally through a movable disk-lil e clamp section L1 and the bolt head
engages this movable section An inwardly projecting lug on the movable
section of the clamp serves to limit its movement toward the section of the clamp
con tituted by the supporting rod heid K A groove in the inner fact of the
adjustable clamp section serves to make engagement between the clamp and an
adjustable curier rod M of the head rest This carrier 1od is rounded on its
surface which engages with the clamp groove and is provided with a flattened
side m which bears against the inner face of the limp section con tituted by the
hend K of the head rest supporting rod J A bow-like head rest cirit Mis
1igidly connected with the upper end of the cartier rod and a curved on naved
leid rest block of frame N is jointed in the carriers as to be capable of swinging
oi rocking the block being pivotally connected with the inwardly project: ends
of the carrier
• lick
A head iest pad O (in this instance a singing pid
strap is employed) is connected with the head ret block Side pids O 0' (see
dotted lines Fig 7) are suitably attached to the mer suifices of the ends of the
concive head rest block N, and the slack strap pase loosely over the e side
pads and is attached to the outer surfaces of the ends of the head rest blo k, thus
providing for a free self-adjustment of the slack strip to the head of patient
seated in the chair
'
r
From the above description it will be seen that the head rest pad his very

page_text: wide range of adjustment, and that it is adapted to swing freely in its carrier to
readily adjust itself to the proper position for supporting the head of a patient
seated in the chair As the head rest proper or pad is pivotally suspended or
hung in its carrier with its central portion below the points of pivoting, it will be
seen that the pad is rendered self adjusting or is readily swung or rocked by the
pressure of the head upon it, without interfering with the various adjustments
which may be imparted by the head re-t supporting rod and the carrier rod It
will further be seen that as the supporting 1od J is supported by the frame bar
independently of the back pad, this pad may be moved up or down without altering
the position of the head rest pad, so that after a patient is seated in the chair and the
head rest properly adjusted the back pad may freely be adjusted to accommodate
the patient
In the top of the box P in which the various parts of the chair may compactly
be packed for convenient transportation (see Fig 4) there are two opening, RR
into which project, when the lid of the box is closed, metal tubes S S secured to
opposite sides of the box Ihese tubes con-titute sockets for supporting the
standards IT of a foot rest shown as provided with three step-like ret tttnt
different heights for the feet of patients occupying the chair The box is adjusted
so as to con titute a platform or foot board for the chair when in position for use
as plainly shown, the diverging fiont legs straddling the box
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
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1 The combination, in a dental chan, of the fiame bar adjustable as to
inclination, the front and rear supporting legs having jointed connection therewith
above its lower end, the adjusting arm having jointed connection at one end with
the fi me bar and adjustable and detachable connection at its opposite end with
the rear supporting leg, means for maintaining the adjusting bar in the position of
adjustment, the seat adjustable up and down the frame bar, and means for
maintaining the sent in its position of adjustment either above or below the
Juncture of the legs with the frame bar, substantially as set fo th
2 The combination, in a dental chair, of the frame bar, the front supporting
legs, the rear supporting les composed of the upper and lower sections, sud lower
section having turning connection with the upper section and being provided with
the cross foot bar having the two bearing po nts, one at each extremity thereof
and by which only it has contact with the floor, the chair seat supported by the
fiame bar and adjustable up and down, and means for maintaining the seat as
adjusted, substantially as set forth
3 lhe combination, in a dental chair, of the supporting legs, the frame bar
having connection with said legs above its lower end and provided with the guide-
way extending lengthwise thereof both above and below the juncture of the frame
bar with the legs, the seat-supporting arm having the slide adjustable upon the
frame bir guide-way, and means by which said arm may be upheld in its position
of adju tment to secure the scat cither below or above the juncture of the logs
with the frame bar, substantially as set forth
4 The combination of the seat-supporting arm, the swinging seat attaching rods
pivotally connected with said arm, the flexible scat, and its stretcher bars carried
by the seat attaching rods, substantially as set forth
5 Ihe combination of the fi ime bar, the seat-supporting arm fitted to slide at
its inner end upon the frame bar and provided with the bearing sockets at its outer
end, means for maintaining the seat supporting aim in its position of adjustment
upon the fiame bar, the swinging seat-attaching rods pivoting in the bearing
sockets of the seat-supporting arin, the flexible seat, its stretcher bars carried by
the seat-attaching rods, and means for limiting the swinging movement of the
seat-attachings rods, substantially as set forth
6 The combination of the back pad carrier provided with the bearing sockets

page_text: and lateral projections, the swinging pad-attaching rods pivoting in said bearing
sockets and bearing downward upon said lateral projections, the flexible back pad,
and its stretcher bars carried by the pad-attaching rods, substantially as set forth
7 The combination in a dental chair, of the frame bar, the seat adjustable along
said bar, means for upholding the seat in its position of adjustment, the back pad
carrier adjustable along the frame bar independently of the seat, means for
securing it in its adjusted position, the head rest pad, its vertically adjustable
supporting rod supported by the frame bar independently of the seat and back pad
carrier, and means for securing said rod in its position of adjustment, substantially
as set forth
8 The combination of the bow-like head rest carrier, means for adjustably
supporting it, the curved or concaved bead rest block or frame pivotally connected
at its ends with said carrier to swing or rock freely, the side pads supported upon
the inner surfaces of the ends of the head rest block or frame, and the slack strap
pad having connection at its ends with the head rest block or frame, substantially
as set forth
Dated this 18th of March 1895
ARTHUR WILLIAM BROWNE