CN106264962B

CN106264962B - Dental patient chair

Info

Publication number: CN106264962B
Application number: CN201610464627.1A
Authority: CN
Inventors: G·马蒂乌佐
Original assignee: Cefla SCARL
Current assignee: Cefla SCARL
Priority date: 2015-06-23
Filing date: 2016-06-23
Publication date: 2019-12-20
Anticipated expiration: 2036-06-23
Also published as: EP3108867A1; CN106264962A; EP3108867B1

Abstract

The present invention relates to a dental patient chair. The mechanism for moving a reclining chair (1), preferably a dental patient chair, comprises a backrest (2) and a seat (3) moving relative to each other, wherein the backrest is supported by a swinging mechanism, the mechanism for moving the reclining chair (1) further comprising: at least one cam (14) having a preset curved profile, supporting the seat and oscillating at least about an axis substantially corresponding to the oscillation axis of the seat; at least one carriage or slider (12); at least one guide hole or slot (11) for the carriage (12). A guide hole or slot (11) extending substantially in the direction of the profile of the cam, the bracket having cooperating means cooperating with the profile of the cam; during the sliding actuation of the carriage by the oscillating mechanism of the backrest, the carriage, which interferes with the profile of the cam, commands at least an oscillating movement controlled by the profile of the cam itself, when it slides inside the guide hole or slot due to the actuation system.

Description

Dental patient chair

Technical Field

The invention relates to the technical field of dental patient chairs. More particularly, the present invention relates to an apparatus and method that allows movement of the chair via a mechanism that utilizes a cam and a circular hole within which a carriage slides that actuates the cam.

Background

In dental history, dentists have worked standing in the past, and today dentists are working sitting, at least until 1960. Dental unit manufacturers strive to provide dental treatment units that allow dentists to work in an ergonomic manner, i.e., work comfortably, and provide dental treatment without harming their musculoskeletal system.

At the same time, the dental patient chair must be comfortable for the patient: the patient feels more comfortable and looser and the dentist works easier.

Furthermore, in general, dental patient chairs should allow supporting the patient in a so-called head-low position. The head-low-foot position or the impact-resistant position is a position in which the patient must lie down in the event of an impact or during the performance of a special examination. The patient lies supine, lying flat, with her/his head below her/his knees and her/his pelvis.

Dental patient chairs have been manufactured industrially for over 100 years; patents relating to dental patient chairs are: for example, EP0477762 by Pelton and Crane, EP0253943 by Castellini, US4173372 by Reynolds.

The above-referenced patents, as well as many others, describe the internal structure of the chair, allowing the chair itself to be moved. In fact, a typical dental patient chair allows a position in which the backrest forms an angle of about 90 ° with respect to the floor (upright position) and a position in which the backrest is parallel to the floor (reclined position), all positions being intermediate between these two extreme positions. These chair positions are achieved by a variety of relatively complex mechanisms and actuators. Moreover, the intervention of replacing or modifying the parts of the mechanism in order to modify the law of relative motion between the backrest and the seat is complex and time-consuming, since one needs to access and disassemble a considerable part of the articulation chain between the backrest and the seat.

DE202011109649U discloses a chair according to the preamble of claim 1. The disclosed therapeutic chair (1) comprises a seating surface (2), a backrest (3), a base (4) and an adjustment system (7). The adjustment system comprises a first guide rail (8) in the form of a first guide hole or slot and comprises at least one second guide rail (9) also in the form of a guide hole or slot. The guide pin (10) engages both the first and second slots. The first slot (8) and the second slot (9) are arranged onto each other such that the seat surface (2) is adjusted relative to the backrest (3) when the adjustment system (7) is adjusted between a first end position (16) and a second end position (17) of a guide bolt (10). The seating surface cannot be raised freely from the adjustment mechanism and access to the mechanism is not allowed by simply swinging the seating surface upward. Conversely, to remove the seating surface to allow access to the mechanism, the seat has to be removed from the mechanism or the mechanism has to be accessed from the other side.

Disclosure of Invention

The object of the present invention is to provide a mechanism that allows positioning of the backrest from the upright position to the reclined position (and vice versa) that is efficient and inexpensive to produce. Moreover, the mechanism produces a coordinated movement with the seat, swinging until reaching the correct ergonomic position of the patient; the chair may be rocked to a head-low and foot-high position if desired.

Another object is the possibility of varying the geometrical laws governing such movements in a simple and effective manner: the movement itself can be accelerated or decelerated, or in any case modified as desired, by changing the geometry of the cam.

Another object is to allow access to a specific position of the patient with a predetermined angle between the torso and the legs of the patient.

The advantage of the present invention is that it consists in a mechanism with a particularly simple construction, using a single actuator, which does not require special tools for production; a mould is not necessary and simple shaping of the part obtained from the element consisting of sheet metal is sufficient.

In a preferred embodiment, the simplified mechanism of the present invention utilizes a minimum number of parts, which is reduced to six. The components are 2 x 2 identical components, mounted in symmetrical positions, so that only three components are to be produced. By comparison, patient chairs known today comprise at least ten symmetrical parts and therefore have to be produced in a side-to-side fashion, so that at least twenty parts are to be produced.

By providing a cam that oscillates about a horizontal axis transverse to the longitudinal axis of the chair, and which is not coupled or locked to the rest of the adjustment mechanism (in particular the cooperating bracket), the seat can be easily raised, the oscillating mechanism allowing access to the mechanism in a very simple and quick manner, similar to a car cover.

The proximity of the adjustment mechanism and the coupling of the cam to the mechanism only via the axis of oscillation allow to easily change the cam in order to change the geometry of the adjustment system and the relation between the positions of the backrest with respect to the corresponding positions of the seat when displacing the backrest from the upright position to the reclined position and vice versa.

According to one embodiment, the cam cooperates with the bracket, the surface of the cam being urged by gravity against the cooperating means of the bracket.

Drawings

Other advantages and features of the present invention are disclosed in the following description, wherein exemplary embodiments of the present invention are explained in detail based on the accompanying drawings:

fig. 1 is an isometric view of a dental patient chair in a reclined position;

fig. 2 is an isometric view of the dental patient chair in an upright position with the interior trim removed;

fig. 3 is an isometric view of the dental patient chair in a fully reclined position (head low and feet high) with the interior trim removed;

FIG. 4A is a side view of a dental patient chair in an upright position;

FIG. 4B is a side view according to FIG. 4A, with the cam highlighted;

FIG. 5A is a side view of a segment of a chair in a reclined position;

FIG. 5B is a side view according to FIG. 5A, with the cam highlighted;

FIG. 6A is a schematic illustration of a patient in an iso weight position;

fig. 6B is a schematic view of a patient in an inclined position.

List of reference numerals

1. Dental patient chair

2. Back support

3. Seat with a detachable cover

4. Chair base

5. Arm of zooming instrument

6. Interior support

7. Motor speed reducer

8. Arch frame

9. Wheel

10. Lifting plate

11. Holes or slots

12. Bracket

13. Axial line

14. Cam wheel

Detailed Description

Fig. 1 shows a typical dental chair comprising a backrest 2, a seat 3, a base 4 and a pantograph arm 5. The pantograph arms 5 allow the raising and lowering of the seat 3, represented by a height of 360mm to 840 mm. At the top of the pantograph arm is some sort of turret for supporting the mechanism for reclining the back and the mechanism for moving the seat in unison. The chair 1 is shown with the backrest reclined, almost parallel to the floor.

Fig. 2 shows the same chair 1 in an upright position, with the backrest 2 at about 70 ° to the floor and the seat 3 at about 12 ° to the floor. The trim has been removed from the seat 3 to reveal internal mechanisms that allow movement of the chair.

Fig. 3 shows the same chair fully reclined in the head-low position, with the backrest 2 almost parallel to the floor and the seat 3 positioned so that the patient's legs are slightly raised relative to the patient's head. The trim has been removed from the seat 3 to reveal internal mechanisms that allow movement of the chair.

In fig. 2 and 3, the trim support 6 and the motor reducer 7 are evident.

Fig. 4A and 4B show a length of the dental chair 1 in the same position of fig. 2 to make the operation of the movement mechanism clearer. Fig. 4A and 4B show the starting point of the movement that causes the backrest 2 to recline.

The motor reducer 7 is activated to initiate a rotational movement of the arch 8 along the hole or slot 11 via the bracket 12. Alternatively, the carriage may be constituted by other sliding elements (for example sliders or the like) guided along the slot 11. Integrated with said arch 8 via a transverse shaft, the wheel 9 engages a cam 14 present in the lifting plate 10, the fulcrum of the lifting plate 10 being on the axis 13, starting to lift vertically, moving the seat support 6. It is worth mentioning that the two cams 14 are mounted on the outer side of the frame element supporting the back recliner mechanism and each cam is simply inserted with a support hole on a support shaft which is stationary and integral with said frame element, which is in fact the fulcrum axis 13. This configuration ensures a very simple and direct access to the cam 14 and makes a quick replacement thereof possible.

Other alternatives may realize a cam 14 with two parts, to which the supporting frame has its stable fulcrum on the axis 13 and the part supporting the profiled edge according to the law of motion is fixed in a releasable manner. In this way, the law of motion can be modified simply by: the profile section is replaced, for example the seat is removed and the cam 14 is manually lifted in order to try to fix the movable profile section to the stable section.

In this way, not only is it easy to adjust, but also possible maintenance and trimming is easy to perform.

Fig. 5A and 5B show a length of the dental chair 1 in the same position of fig. 3. Fig. 5A and 5B show the movement of the wheel 9, now in its end-of-travel position, thus causing the seat support 6 supporting the upholstery to rise.

It is evident that the extension of the rise angle and the law of dynamics with which the rise takes place depend on the geometry of the cams 14 present on the underside of the rising plate 10. As the radius of the cam and its centre (in the case of a circular cam) change, the width of the angle at which the rise of the seat is achieved and the speed at which the rise is allowed to occur can vary. By designing the cams with different geometries (elliptical, parabolic, hyperbolic), the acceleration and lifting pattern of the backrest is varied.

In the embodiment shown here, the movement of the backrest 2 and the seat 3 takes place in a coordinated manner such that, as the backrest is lowered, the angle between the torso and the legs of the patient gradually increases, from about 95 ° to about 180 °.

In an alternative embodiment (not shown), the design of the cam has a geometry, such as for coupling a specific position of the backrest with a specific inclination of the seat, resulting in the possibility of reaching the patient position, wherein:

roughly, the patient's torso is 25 ° with respect to the floor, while the patient's thigh is perpendicular to the floor, and her/his femoral head is parallel to the floor; the angle between the torso and the thighs of the patient is 130 °. In this position, the weight of the patient is evenly distributed (iso weight, most comfortable position); the position of the patient is schematically shown in fig. 6A.

The torso of the patient is in an optimal position for the dentist, while the relative angle of the seat holding with respect to the backrest is stable. The angle between the torso and thigh of the patient is about 105 and 120 (oblique position); the position of the patient is schematically shown in fig. 6B.

In other words, the angle between the torso and the thighs of the patient may be kept in the range of 95-130 °, but the patient is reclined, with the height of her/his head appropriate for the dentist to work. This position is very comfortable for the patient, distributing her/his weight evenly, while at the same time being ergonomic for the dentist.

In another embodiment, not shown, the cam may be designed such that the end point of the fully reclined position brings the patient to a position that is fully horizontal to the floor (patient table).

From all the above, it can be understood that in the chair according to the invention, the relationship between the moving backrest and the moving seat influences the shape of the cam profile in an almost intuitive and direct manner, so that the coordinated movement of the backrest and the seat is designed to operate relatively directly.

Claims

1. A mechanism for moving a reclining chair (1), said mechanism for moving a reclining chair (1) comprising a back (2) and a seat (3) moving relative to each other, and wherein said back is supported by a swinging mechanism, said mechanism for moving a reclining chair (1) further comprising:

-at least one cam (14) having a preset curvilinear profile, which supports the seat and oscillates at least about an axis substantially corresponding to the oscillation axis of the seat;

-at least one carriage or slider (12);

-at least one guide hole or slot (11) for said carriage or slider (12);

it is characterized in that the preparation method is characterized in that,

said guide hole or slot (11) extending substantially in the direction of the profile of said cam,

the carriage or slider (12) having cooperating means cooperating with the profile of the cam (14);

during the sliding actuation of the carriage or slider (12) by the oscillating mechanism of the backrest, when the carriage or slider (12) slides inside the guide hole or slot (11) thanks to an actuation system, the carriage or slider (12) interfering with the profile of the cam (14) commands at least an oscillating movement controlled by the profile of the cam (14) itself; and is

In a position in which the cam (14) is at a distance from the cooperating means of the carriage or slider (12), the cam, which can be freely displaced by oscillation, forms a position in which it interferes in cooperation with the cooperating means.

2. The mechanism for moving a reclining chair (1) according to claim 1, wherein said cam (14), said carriage or slider (12) and said guiding holes or slots (11) can be produced in a single type by sheet punching and installed 2 x 2, or even more as required.

3. The mechanism for moving a reclining chair (1) according to claim 1, wherein said cam (14), said bracket or slider (12) and said guide hole or slot (11) can be produced and installed in a single type, maintaining a specific profile achieved in a side-to-side type.

4. The mechanism for moving a reclining chair (1) according to any of claims 1 to 3, wherein said cam (14) has an arc of a circle, or an ellipse, or a parabola, or a hyperbola, or a linear profile, or a combination of the foregoing.

5. The mechanism for moving a reclining chair (1) according to any of claims 1 to 3, wherein said cam (14) comprises an interrupted or undulated profile with convex and concave surfaces, so that the patient is brought into a position in which the patient is substantially parallel to the floor, and then in a position in which the patient has her/his head at the height desired by her/his dentist but the patient's torso forms an angle comprised between 105 ° and 130 ° with respect to her/his thigh.

6. The mechanism for moving a reclining chair (1) according to any of claims 1 to 3, wherein the shape of said cam (14) allows to bring the patient in a position perfectly parallel to the floor.

7. Mechanism for moving a reclining chair (1) according to any of claims 1 to 3, wherein said actuation system is selected from the group consisting of at least one motor reducer (7), hydraulic and/or pneumatic and/or manual system.

8. Mechanism for moving a reclining chair (1) according to any of claims 1 to 3, wherein said cam or two cams are mounted outside the supporting central turret, each cam being located on an axis of oscillation of a corresponding side of said supporting central turret, said axes being coaxial to each other.

9. The mechanism for moving a reclining chair (1) according to any of claims 1 to 3, wherein said cam or cams is/are constituted by a substantially flat plate, shaped to correspond to the cam profile, and can be exchanged from the outside of the chair support mechanism to other cams with different profiles, so as to modify the law of motion between the backrest and the seat.

10. Mechanism for moving a reclining chair (1) according to claim 1, wherein said reclining chair is a dental patient chair.

11. Method for moving the back (2) and the seat (3) of a reclining chair (1) with respect to each other with a mechanism according to any of claims 1 to 10, wherein the possibility of movement of the back and the seat depends on the geometry of the cam (14).

12. The method of claim 11, wherein the reclining chair is a dental patient chair.