Dental treatment chair system

A dental treatment system comprising a treatment chair seat, a backrest mounted tiltably thereto, and a headrest characterized in that the device includes a unit box assembly adapted to be stored inside or underside the backrest and to be drawn out therefrom. The unit box assembly having a variety of instruments housed therein is designed such that the instruments may be positioned in the space on the shoulder of the backrest or on the side of the headrest or on both of the shoulder and the side because of the construction of the assembly that, when the box assembly is stored in the backrest, it may be interlocked with the tilting of the backrest and, when drawn out therefrom, may be freely moved, stopped, vertically and bilaterally rotated and stopped independently of tilting the backrest to thereby facilitate handling of the instruments and to save additional space for separate arrangement of instruments.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates generally to a dental treatment chair system and 
more particularly to a dental treatment chair system which makes it 
possible to suitably change the direction in which to manipulated a dental 
instrument in accordance with the position and type of treatment a patient 
undergoes and with the position and posture the operator takes during a 
particular treatment. 
2. Prior Art 
In dental treatment, it is considered essential for optimum treatment, to 
change the direction in which an operator manipulates an instrument in 
accordance with the purpose of treatment, the oral region being treated 
and the position and posture of the operator. Accordingly, there have been 
many ideas as to where the instruments should be disposed with reference 
to a treatment device. A description will now be given roughly outlining 
the problems in conventional devices of this nature, which have not yet 
been solved. 
In similar types of conventional devices, Type (a) features instruments 
which are directly mounted to a backrest freely tiltable with respect to 
the seat of a treatment chair; Type (b) features instruments which are 
mounted to a tray table or tray arm; Type (b-2) features instruments which 
are mounted to a spittoon portion and Type (b-3) features instruments 
which are mounted to a movable cart, etc. The types of conventional 
devices described above have both pros and cons. In particular, Type (a), 
in which the instruments are directly mounted to the backrest, is much 
more functional. Type (a) is more functional because it enables the 
assembly of flexible connection pipes connected to the instruments, stores 
the pipes inside the backrest with the pipes out of view and dispenses 
with a long arm and an exposed support which are provided independently of 
the chair device, saving such sagging exposure of the flexible connection 
pipe being provided with a tray and a spittoon and further increases 
manipulability of the instruments without forced posture on the part of 
the operator, enhances the outer apperance of the invention and does not 
cause the patient to feel wariness or terror. The present invention is an 
improvement over Type (a) and a description will now be given of the 
present invention with reference to the prior art of Type (a) and also in 
conjunction with its inherent problems, which have not yet been solved. 
The device of Type (a) (of the Prior Art) is designed so that the 
instruments are detachably mounted either to the shoulder of a backrest, 
to the side of a headrest or to both the shoulder and side (Japanese Pat. 
No. 444,604, equivalent of U.S. Pat. No. 3,198,574). The device of Type 
(a) is advantageous in that the operator is seated during treatment of a 
patient and is relieved of the trouble and effort of pushing himself 
onward or twisting himself to reach an instrument irrespective of whether 
the instruments are mounted on the right or left side of the treatment 
chair, thus making treatment more efficient and lessening the fatigue on 
the operator. But this design is still problematic in that during the 
treatment activity in a seated position of 9 to 12 o'clock the flexible 
connection pipe entwines around the operator's hand and obstructs his 
field of vision thereby interfering with the treatment activity, as will 
become apparent from a description to be given presently. 
SUMMARY OF THE INVENTION 
In order to solve the problems inherent in the previous invention, the 
present invention has generally incorporated a unit box assembly (to be 
later described) therein, and intends to increase the aptitude of the 
previous invention not only by arranging the instruments in the same 
position as that of the previous invention to thereby retain those 
advantages, but also by additionally making it possible to move the 
mounted position of the instruments outwardly of the backrest and to 
change the direction of manipulation of the instruments by the operator 
through movement and rotation in their stored state even after the 
instruments have been released from their stored state so as to be brought 
into agreement with the position and posture of the operator. 
As shown in Type (b), described above, the movability of rotatability is 
imparted to a spittoon or a cart independent of the chair device and 
instruments are mounted to the spittoon or the cart, or a device of the 
type in which a long arm or an exposed support is added to support the 
tray table rotatably and instruments attached to the tray table may fit 
for various positions and postures the operator takes during treatment 
activity from the viewpoint of the direction in which to manipulate the 
instruments, but when consideration is given to the effects which the 
assembly described above produces on the patient when he is not undergoing 
treatment, namely the unshapely sagging of flexible connection pipes 
connected to the instruments, the presence of an arm and a support which 
is offensive to the eye of the patient and within his reach, wariness and 
terror caused by the presence of the arm and the support, and in turn, 
additional members which may interfere with the space used by the operator 
during treatment activity. It will become apparent from a description to 
be given hereinafter that the advantages of the present invention can be 
evaluated in distinction from those of the prior art treatment chairs of 
the type described. 
A description will now be given of the treatment chair system of the 
present invention with reference to the drawings showing embodiments 
thereof.

DETAILED DESCRIPTION OF THE INVENTION 
In the invention, a unit box assembly 14 is mounted to the inside or the 
underside (inside a backrest 2 in the case of the system shown) of a 
backrest 2 tiltable with respect to a seat 1 of the treatment chair system 
so as to permit free storing in and drawing out of the backrest 2. This 
assembly 4 includes a unit box 5, rotary arms 6, 7, 8 and an arm support 9 
as shown in the embodiment in FIGS. 1 through 11. More particularly, the 
assembly includes, in addition thereto, various instruments 11, 11 . . . 
from the top 51 of the unit box 5 together with flexible connection pipes 
12, 12 . . . respectively connected thereto in a freely drawable and 
retractable manner over the desired lengths of the pipes and, to this end, 
the unit box 5 incorporates therein a drawing and retraction means (not 
shown) for the flexible connection pipes 12 . . . including pulleys. A 
control device (not shown) for supplying electricity and fluid such as 
air, water, medical solution, mist, etc. to the connection pipes 12 . . . 
freely continuously and discontinuously may be mounted either inside the 
box 5 or may be housed in a seat 1 or other base portion 13. The 
connection pipes 12 . . . and control device and/or fluid source may be 
connected to each other by housing separate flexible tubes (not shown) in 
or extending the same along the arms 6, 7, 8. The unit box 5 is mounted in 
a horizontal position rotatably by a vertical shaft 6.sub.1 to a first arm 
6; the first arm 6 is mounted in a horizontal position rotatably by a 
vertical shaft 7.sub.1 to a second arm 7; the second arm 7 is mounted in a 
horizontal position rotatably by vertical shaft 8.sub.1 to a third arm 8; 
the third horizontal arm 8 is in a vertical position rotatably mounted to 
an arm support 9 by a horizontal shaft 9.sub.1 and the support 9 is 
provided with a horizontal piece 9.sub.2 bearing the third horizontal arm 
8 horizontally. The arm support 9 is fixed to a support member 10 
protrudently provided on the backside of the seat 1. 
For the details of the drawing and retraction means in the unit box 5 and 
for the details of a cartridge system sheath in the box 5, reference can 
be made respectively to the disclosure of Japanese Utility Model 
Publication No. 40626/1977 and to the disclosure of Japanese Patent 
Publication Laid Open to Public Inspection No. 96296/1978 and accordingly 
a detailed description of the means and the sheath is omitted. 
Since the unit box assembly 4 is of the construction described above, it 
will be understood that the unit box 5 is horizontally rotatable around 
three vertical shafts 6.sub.1, 7.sub.1, and 8.sub.1 through the arms 6 and 
7, and that the box is vertically rotatable around one vertical shaft 
9.sub.1 thorugh the arm 8 (but is stopped from its rotation in a 
horizontal state by the support 9). In order to store the unit box 
assembly 4 neatly in the backrest 2, the backrest 2 is provided on the 
backside thereof with a storing recess 14. The unit box assembly 4 stored 
in the backrest 2 on the left side facing the front of the chair from the 
ordinary treatment position of an operator as shown in detail in the plan 
view in FIG. 2 and the top 51 of the box 5 is in registry with the 
shoulder of the backrest in such a manner that the instruments 11 . . . 
are positioned in the space of the shoulder of the backrest 2, in the 
space of the side of the headrest 3 or in the space of both the shoulder 
and the side so as to follow the concept of Japanese Pat. No. 444604 and 
to retain the convenience for the operator in treatment. 
A description will now be given of how the unit box assembly 4 is 
associated with the tilting of the backrest 2. When the backrest 2 is 
raised from the state in FIG. 3 to the state in FIG. 6 with the unit box 5 
retained on the backside of backrest 2 as by hooks (the state is called a 
stored state), the arm 8 follows the raising of the backrest 2 and pivots 
around a horizontal shaft 9 to bring about a state shown in FIG. 6. In 
order to show such an operation, the horizontal shaft 9 is arranged on 
substantially the same line as a tilting shaft (not shown) of the backrest 
2. In this state, the unit box 5 is freely movable and rotatable within 
the storing area of plane by expansion, contraction, horizontal and 
vertical rotation of the arms 6, 7 and 8. 
When the unit box 5 is moved away from the backrest 2 (when the box 5 is 
released from its stored state), the box 5 falls of its own weight in 
accordance with the vertical rotation of the arm 8 but is supported and 
stopped horizontally by a horizontal block 9.sub.2 of the arm support 9 
and is brought from a state in FIG. 6 into a state in FIG. 7. This means 
that even when the unit box 5 is released from the backrest 2 placed in 
its horizontal position in FIG. 3, the box 5 is held horizontal as shown 
in FIG. 5. In short, in the example illustrated, the unit box assembly 4, 
when held stored in the backrest 2, follows the tilting of the backrest 2, 
but when released from storage, the assembly is always held horizontal 
irrespective of the tilting of the backrest 2. Accordingly, after the 
assembly 4 has been held horizontal, the unit box 5 can be moved to a 
position fit for the position and posture which the operator takes for 
treatment by horizontal rotation of the first arm 6 and second arm 7. 
Shown in FIG. 4 is an example of the state in which the unit box 5 is drawn 
out from its stored state in the backrest to an exposed state. In the 
example, the unit box 5 is provided inside the backrest 2 corresponding to 
the left of the chair, but an example in which the unit box 5 is provided 
on the right side of the backrest 2 for convenience of a left-handed 
operator (or a nurse or an assistant) and the state of the box 5 being 
drawn out from the backrest 2 are shown respectively in FIGS. 8 and 9. 
Furthermore, an example in which two box units 5 are mounted on the right 
and left sides of the backrest 2 and the state of the box units 5 being 
drawn out from the backrest 2 are respectively shown in FIGS. 10 and 11. 
In another embodiment of the invention shown in FIGS. 12 and 14, the unit 
box assembly 4 is designed not only to be stopped and held horizontal in 
its vertical rotation after the assembly 4 has been drawn out from the 
backrest 2 in the same manner as in the preceding embodiment but also to 
be enlarged in its area of vertical rotation and to be stopped in its 
vertical optionally tilted position including a horizontal position. 
Namely, the unit box assembly 4 of this embodiment comprises a horizontal 
rotary arm 6, a vertical rotary arm 8' designed to be freely vertically 
rotated and stopped with respect to the arm 6 by an adjusting screw 
9.sub.1 ', a horizontal arm 7 secured in a horizontal position movably to 
the arm 8', and a frame 10' provided inside the backrest 2 for fixedly 
supporting one end of the arm 7. When this embodiment is compared with 
that of FIG. 1 it is apparent that the vertical rotary arm 8 in FIG. 1 is 
different from this embodiment in that the arm 8 in the preceding 
embodiment is in this embodiment interposed between the horizontal arms 6 
and 7 and one end of the horizontal arm 7 is directly supported on the 
backrest 2. This difference takes shape in the fact that when the 
adjusting screw 9.sub.1 ' is loosened, the arm 6 and the arm 8' are 
brought into a vertically rotatable relation with each other in such a 
manner that if one arm is a fixed side, the other arm becomes a rotatable 
side. It is apparent that this vertical rotatability increases the area of 
vertical swing of the box 5 over the embodiment in FIG. 1 and makes it 
possible to stop the box 5 in any desired place by use of the screw 
9.sub.1 '. Both embodiments are the same in respect to horizontal 
movability. For clarity of the relevance with respect to the arm and pivot 
in FIG. 12, the members that are the same as those in FIG. 1 are 
designated by the same or primed reference characters. FIGS. 12 and 14 
show respectively a plan view and a side view of the treatment chair 
device in which the unit box assembly of the second embodiment 
corresponding to FIGS. 4 and 7 of the first embodiment is used. 
As apparent from the above description, the second embodiment provides a 
greater variety of directions for manipulation of instruments 11 in 
response to the postures of the operator during treatment. 
A description will now be given of how the box unit assembly of the 
invention can be adapted for a particular position of the operator during 
treatment by comparison with the Japanese Pat. No. 444604. Before making 
the comparison between the two, various positions of the operator for 
treatment are described briefly, in the fashion of a clockface with 
reference to FIG. 15. When a medium line of a headrest 3 is brought into 
line with a line of 12 to 6 o'clock, a semicircular area below the line 
corresponds to 11, 10, 9, 8, and 7 o'clock. The operator generally takes a 
seated position in the 12 o'clock position, but depending upon 
circumstances, he may first find it necessary to carry out treatment in 
the 9 o'clock position. Of course, he may possible move to the 
mid-position between 12 and 9 o'clock. When the operator shifts from his 
seated position to an upright position, the backrest 2 moves from a 
horizontal to an erect position and the operator is seated off to the left 
of the backrest 2. The position and posture of the operator for treatment 
in which the invention displays its usefulness to the fullest extent is in 
the seating positions of 12 to 9 o'clock (particularly 9 o'clock). A 
description will hereinafter be given of this fact. 
(1) Seating position at 12 o'clock: 
As apparent from comparison between FIGS. 16 and 18, when the operator is 
in this position and posture, instruments 11 . . . are in the space on the 
shoulder of the backrest 2 on the side of the headrest 3 and in the space 
area of the shoulder and the side, and not only can the operator o freely 
draw and retract the instruments 11 . . . closest to the mouth of a 
patient but also flexible connection pipes 12 are placed outside the area 
of movement of a right arm o.sub.1 of the operator o, with the result that 
the therapeutic effect which the present invention can produce is entirely 
the same as in the previous invention. 
(2) Seating position at 9 o'clock: 
In the box unit assembly according to the previous invention in FIG. 17, 
when the instrument is drawn out, the flexible connection pipe 12 is 
suspended in the state of the pipe twining around the right hand o.sub.1, 
and accordingly the pipe 12 interferes with the operation and visual field 
of the operator when treatment is carried out by the right hand o.sub.1. 
In contrast thereto, in the present invention, as shown in FIG. 19, when 
the unit 5 is arranged as shown, it is possible to carry out treatment 
without the pipe 12 entwining around the right hand o.sub.1 and 
accordingly the invention is far more advantageous than the previous 
invention. 
It will be understood that the embodiments illustrated are merely one form 
of the invention shown by way of example and many other modifications of 
the invention which can be adapted for the position and posture for 
treatment may be made without departing from the scope and spirit of the 
invention. 
As apparent from the description above, the invention not only retains the 
advantages of the previous invention by storing the unit box having 
instruments mounted drawably and retractably from the top thereof in the 
inside (or underside) of the backrest and normally placing the instrument 
mounting portion of the unit box in the space on the shoulder of the 
backrest, on the side of the headrest or both on the shoulder and on the 
side, and also provides the new advantage that when the unit box is 
released from its stored position and after it has been drawn out from the 
backrest, the box can be freely moved, rotated vertically and bilaterially 
and stopped independently of tilting of the backrest. Accordingly, the box 
does not interfere with treatment operation even in the seated positions 
of 12 to 9 o'clock. 
The invention has an additional advantage in that when the unit box is not 
drawn out from the backrest, the box is stored and concealed on the inside 
or the underside of the backrest and even when it is drawn out, the box is 
held in a preset state suited for treatment and is pleasing in appearance, 
does not interfere with the sphere of activity of the operator, does not 
cause any uneasiness or anxiety on the part of the patient and can save 
additional space for the box.