FI131519B1

FI131519B1 - Dental patient chair

Info

Publication number: FI131519B1
Application number: FI20235294A
Authority: FI
Inventors: Olli Kattelus
Original assignee: Planmeca Oy
Priority date: 2023-03-13
Filing date: 2023-03-13
Publication date: 2025-06-05
Also published as: FI20235294A1; WO2024189267A1

Abstract

Invention relates to dental patient chairs comprising a seat part (31) and an elongated back rest (32) having a bottom end at a seat part end thereof, and a top end at the opposite end. A control system of the patient chair comprises a user interface configured to enable sending a control command to a first motorized construction (M1) designed to alter a height position of the seat part (31) relative to its support structure (35) and to a second motorized construction (M2) designed to alter a tilt angle between the seat part (31) and the back rest (32). As a response to an initial input from the user interface, the control system initiates driving of the motorized constructions (M1; M2) to generate a combined movement which changes the height position of the seat part (31) and the tilt angle of the back rest (32) such that, considering a reference point (R) at a given short distance from the top end of the back rest (32), that reference point (R) will be at the same height position at the end of the combined movement than where it was when the initial input was received.

Description

DENTAL PATIENT CHAIR

FIELD

The invention relates to dental patient chairs, particularly to controlling movements of certain components of dental patient chairs.

BACKGROUND

Historically, dental patient chairs were designed to support a sitting patient and dentists were accustomed to work in a stand- ing position. This caused the dentists having to work at unergo- nomic positions and was prone to cause health problems.

Modern dental patient chairs are designed not only in view of pa- tient comfort but specifically in view of working ergonomics re- garding various dentist’s working positions. A modern dental pa- tient chair comprises several components whose position can be adjusted and in the more advanced solutions, the dental patient chair may comprise motorized drives to adjust vertical and hori- zontal position of a seat part, tilt of a back rest in relation to the seat part, position and tilt of a head support in relation to the back rest, and tilt of a leg support in relation to the < 25 seat part. A dental patient chair may be a stand-alone apparatus

S and comprise a user interface of its own, realized by buttons ar- — ranged to the chair itself, for example. On the other hand, the 3 chair may be a physical and functional part of a complete dental

N care unit comprising a base frame structure, a control system and

E 30 various supports for various components, like for dental care in- x struments and a dental operating light.

N

3

N When having a complex system with several operational functions,

N like several motorized movements of individual parts of a patient chair, also controlling of the various movements gets complex.

This particularly in case of having to separately control various components to achieve a desired complete mutual movement thereof.

One example of such system is presented in a US patent 5,203,609.

SUMMARY

A general objective of this disclosure is to provide one specific way to control certain movements of certain components of a den- tal patient chair, so as to ease operating the chair during treatment or in-between individual treatment operations. This ob- jective is achieved by the construction and control as to be dis- cussed in more detail below.

BRIEF DESCRIPTION OF FIGURES

In the attached figures

Fig. 1 shows one typical modern dental care unit with an inte- grated patient chair,

Fig. 2 shows a differently designed dental patient chair and in a different position than the one shown in Fig. 1,

Figs. 3a and 3b show principles of driving certain chair compo- < 25 nents according to this disclosure,

N

& —- Fig. 4 shows an example of a user interface applicable for use in 3 the context of this disclosure, and

N z 30 Fig. 5 shows as simplified a control system applicable for use in 3 the context of this disclosure. >

S DETAILED DESCRIPTION

As for more general background, in the field of odontology, the term dental care unit (often also just /dental unit’) refers to an apparatus or arrangement which supplies power and also possi- bly control signals to instruments used in connection with dental care operations, and also possibly to various other devices used in connection with dental care operations.

One typical solution used in dental care units is to arrange den- tal care instruments on an instrument console which is supported by a support arm extending from the frame structure of the dental care unit. The dental care unit may comprise more than one and also different support arms, for example for dental assistant's instruments or for other devices used in connection with dental care operations.

One typical solution used in dental care units is to arrange one or more horizontal support arms to a support arrangement which extends vertically from the frame part of the dental care unit.

Such an arrangement is typically implemented either to comprise a certain number of support arms or to enable a certain number of different arm assembly variations, which can be implemented ei- ther when originally assembling the dental care unit or later as a retrofit. Such vertical support arrangement is typically con- nected to the cover structures of the frame part of the dental < 25 care unit. Individual dentists and on the other hand different

S dental clinics, educational establishments and also dentists in —- different cultures have needs and wishes differing from each oth- 3 er relating to equipping a dental care unit with instruments, ac-

N cessories and support arm solutions according to one’s conven-

E: 30 ience. 3

N Fig. 1 shows a basic structure of one typical kind dental care

N unit 1 intended for use in connection with dental care work. The

N dental care unit 1 of Fig. 1 comprises a frame part 2 and a pa- tient chair 3 connected to it. From the frame part 2 extends ver-

tically a support arrangement 4 which comprises a vertically ex- tending support part 41, a first support structure 42 to support diagnostic instruments related to dental care or instruments 6 used in connection with dental care operations, or both, a second support structure 43 for e.g. an operating light 8 or for an X- ray imaging means used in connection with dental care operations, and a third support structure 44 for e.g. a display 10.

Fig. 1 further shows an instrument holder 11, which can be con- figured to support instruments typically used by the dental as- sistant, and a foot control 12 by which functions of the dental care unit 1 and/or devices or structures connecting or coupled to it can be controlled. Additionally, the dental care unit 1 is ar- ranged into operational connection with a data network or an in- dividual computer 13.

It should be noted that the dental care unit of Fig. 1 is only one example. The dental care unit can comprise e.g. more support structures or fewer support structures for different devices than included in the structure of Fig. 1. Also, for example the pa- tient chair does not necessarily need to be integrated with the dental care unit but it can be realized as structure completely separate from a dental care unit. On the other hand, the frame structure like discussed above can be arranged as an integral < 25 part of structures of a floor-mounted chair. Furthermore, instead

S of a structure having considerable horizontal and vertical dimen- — sions as shown in Fig. 1, the frame structure of a dental care 3 unit can be as for its dimensions principally only a minor struc-

N ture from which extend one or more than one support arm. Along

E 30 with or in addition to a foot control, the arrangement can also 3 include a graphical or other user interface. The structure of the

D dental care unit is, however, typically realized such that via it

N are delivered, or can be arranged to be delivered power, fluid

N and/or control signals needed for using the instruments and de- vices used in the dental care operations. Thus, physically this means delivering for example at least one of the following: wa- ter, compressed air, electricity, control signal.

Thus, in the context of this disclosure, when mentioning a dental care unit it basically refers to a structure which includes an 5 arrangement which enables supplying at least one of the above- mentioned or a corresponding variable to dental care instruments and/or a device used in connection with dental care work opera- tions which are arranged in connection with the dental care unit.

The dental care unit of Fig. 1 is thus, as said, one example of a typical dental care unit. The frame structure of the dental care unit may comprise a support structure for a patient chair (a mechanism not visible in Fig.l as the patient chair itself blocks a view to such structure - which may be sturdy support arm), yet a patient chair may also be an independent apparatus. The disclo- sure below is made mostly in reference to an independent patient chair.

Fig. 2 shows a dental patient chair designed differently and in a different position than the one shown in Fig. 1. The dental pa- tient chair of Fig. 2 comprises a seat part 31, an elongated back rest 32 having a bottom end at the seat part end thereof and a top end at the opposite end thereof, a head support 33 and a leg support 34. Differently from the Fig. 1 construction, the seat < 25 part 31 is not supported by a structure extending from the frame

S of the dental care unit but by a base structure 35 designed to be — mounted on a floor. ?

LO

N Figs. 3a and 3b show schematically basic components and a partic-

E 30 ular operation of a dental patient chair as per the current dis- 3 closure. As compared to Fig. 3a, the seat part 31 has been driven

O in Fig. 3b onto a higher horizontal level while a tilt angle be-

N tween the back rest 32 and the seat part 31 has been decreased,

N such that a reference point R locating on a virtual extension of the elongated back rest 32, a distance away thereof, remains at the same height position. This is achieved by a particularly de- signed combined motorized Ml; M2 movement which changes the height position of the seat part 31 and the tilt angle between the seat part 31 and the back rest 32. That is, when knowing the length of the elongated back rest 32 as measured from its physi- cal or virtual pivot axis, as defined by the articulation con- struction A, to the top end thereof, and the distance from the top end of the back rest to the reference point R, one is able to calculate how any change in the tilt angle changes the height po- sition of the reference point R. (It is to be noted that the 10- cation of reference point R in relation to the top end of the back rest needs not to be same in any given circumstance when in- itiating the above-discussed combined movement, and one may even give a position for R which is not further from but closer to the pivot axis than where the top end of the back rest is located.)

In case of the patient chair being supported as shown and dis- cussed in reference to Fig. 1, a motorized drive to adjust height position of the seat part 31 can be arranged to take place in the context of such construction as well. There, frame 2 could corre- spond the base structure as per Fig. 2, and the same mutual posi- tions of the components of the patient chair as shown and dis- cussed in reference to Figs. 3a and 3b could be realized in such context as well. x 25 2 A large number of constructions to alter height position of the — seat part, be that then in the context as per Fig. 1 or Fig. 2, 3 are well known in the field and no details of such are thus pre-

N sented here. The same concerns construction for altering the tilt

E 30 angle between the seat part and the back rest. 3

O It is particular to the current disclosure that realizing of the

N kind of mutual movement of the seat part 31 and the back rest 32,

N as shown in Figs. 3a and 3b, is arranged to take place in re- sponse to a specific command given from a user interface. That is, if considering the position shown in Fig. 3a being "position

A” and that of Fig. 3b being “position B”, as compared to sepa- rately driving the seat part 31 and the back rest 32 from their mutual position A to the mutual position B, the user interface according to this disclosure is designed to provide a single in- put to drive the seat part 31 and the back rest 32 from the mutu- al position A to position B - and obviously also vice versa.

Particularly, such single input is to only drive the motorization

M1 adjusting the height position of the seat part 31 and the mo- torization M2 driving the articulation construction A which ena- bles adjusting the tilt angle between the seat part 31 and the back rest 32. In other words, that single input is not to trigger any other drives the patient chair may have been configured to comprise. Such basically simple combined driving can be arranged to take place, for example, by arranging to a user interface con- figured to control the chair virtual or physical control buttons

SMU and SMD as shown in Fig. 4. The first one of those buttons can be configured to generate a control signal "synchronized move up” (of the seat part) as long as the control command is being given, like as long a respective control button is being pressed, and the second respectively "synchronized move down”, as long as the control command is being input. Obviously, similar control can be arranged to take place, alternatively or in addition, via < 25 other kind of user interfaces as well, like a lever of a foot

S control device, for example. =

LO The above sort of control is different from one in which the con-

N trol system may comprise stored positions of chair components and

E 30 in which a control command may be given to drive the chair compo- 3 nents to a certain position stored in advance in the control sys-

Py tem.

O

S

Fig. 5 shows as simplified a control system applicable for use in the context of this disclosure. The control system may be a part of a stand-alone chair or part of a dental care unit comprising a patient chair. The control system controls motorized drive of the seat part and the back rest as discussed above, as a response to a trigger input from the user interface.

While Figs. 3a and 3b show positions in which the tilt angle be- tween the seat part 31 and the back rest 32 is closer to 45 de- grees than to say 90 degrees, which would correspond to a patient sitting position, the same mutual driving principle as disclosed above can be applied also up to such tilt angles - as well to the other direction like up to, or perhaps rather “down to” even a so-called Trendelenburg position where a patient lies near hori- zontally yet such that the head gets positioned lower than the pelvis. (In such case, the chair may be further arranged to allow for adjusting, separately from the operation discussed above, a tilt angle between the seat part 31 and the leg support 34.)

According to one particular aspect, the control system is ar- ranged to generate the mutual movements of the seat part 31 and the back rest 32 such that, considering the reference point R at a given short distance away from the top end of the back rest 32, it will be at the same height position at the end of the move- ments of the seat part 31 and the back rest 32 than when the con- trol command for the mutual driving of the components was ini- < 25 tially given.

N

& — It is to be noted that while drive of the movements of the chair 3 components discussed above may be arranged synchronized so as to

N all the time keep the reference point R at the same height posi-

E 30 tion, this needs not to be the case. For example, either of the 3 seat part movement or the back rest movement may be arranged to

N take place faster and the desired mutual end position be reached

N only after either of the height position of the seat part or the

N back rest tilt angle has been considered to have reached a de- sired end position. As an example, altering the height position of the seat part may be arranged to be faster and when a desired height has been reached, the back rest will “follow” to complete its total movement so as to ultimately have the reference point R at the same height position as it was at the beginning of the combined movement.

According to one aspect, the control system of the chair may be configured to calculate height position of the reference point R in response to receiving an input to initiate the above-discussed mutual movement from a height position of the seat part 31 and a tilt angle of the back rest 32 at that given moment.

According to one aspect, the dental patient chair comprises a first position sensor indicating a height position of the seat part 31 and a second position sensor indicating a tilt position of the back rest 32, wherein the first and second positioning sensors are optionally arranged to be part of the first and sec- ond motorized driving constructions (Ml, M2). The control system may then be configured to receive position signals from the first and second position sensors in response to receiving the input to initiate the above-discussed mutual driving of the seat part 31 and the back rest 32.

According to one aspect, the motorized drives of adjusting the < 25 height position of the seat part 31 and tilt angle of the back

S rest 32 comprise stepping motors which can be eguipped to contin- — uously provide information of horizontal position of the seat 3 part 31 and of the tilt position of the back rest 32, whereby

N calculation of vertical location of the reference point R can al-

E 30 so be continuous, or needs not to be calculated based on specific 3 position sensor signals upon initiation of the above-discussed

D synchronized movement.

S

According to one aspect, the dental patient chair comprises a seat part 31 and an elongated back rest 32 having a bottom end at a seat part end thereof, and a top end at the opposite end. A control system of the patient chair comprises a user interface configured to enable sending a control command to a first motor- ized driving construction M1 designed to alter a height position of the seat part 31 relative to its support structure 35 and to a second motorized driving construction M2 designed to alter a tilt angle between the seat part 31 and the back rest 32. As a re- sponse to an initial input from the user interface, the control system initiates driving of the motorized constructions M1; M? to generate a combined movement which changes the height position of the seat part 31 and the tilt angle such that considering a ref- erence point R at a given short distance from the top end of the back rest 32, that reference point R will be at the same height position at the end of the combined movement than where it was when the initial input was received.

According to one aspect, the dental patient chair comprises a seat part 31, an elongated back rest 32 having a bottom end at a seat part end thereof and a top end at the opposite end, a sup- port structure of the seat part 35, a first motorized construc- tion MI designed to enable altering a height position of the seat part 31 relative to the support structure of the seat part 35, an articulated structure A connecting the seat part 31 and the back rest 32, a second motorized construction M2 designed to operate < 25 the articulated structure A to enable altering a tilt angle be-

S tween the seat part 31 and the back rest 32, and a control system —- comprising a user interface configured to enable sending control 3 commands to said first and second motorized constructions M1; M2.

N The user interface is configured to enable transmitting a first

E 30 and a second input to the control system, wherein 3 said first input is designed to trigger a combination of

D operations comprising driving said first motorized con-

N struction (Ml) to raise the seat part (31) and driving

N said second motorized construction (M2) to decrease the tilt angle, and said second input is designed to trigger a combination of operations comprising driving said first motorized construction (M1) to lower the seat part (31) and driv- ing said second motorized construction (M2) to increase the tilt angle, and both of the first and second inputs are configured to cause no other component optionally included in the patient chair con- struction to move, and wherein both of said combinations of oper- ations generate such combined movement of the seat part (31) and the back rest (32) that, considering a reference point (R) at a given short distance from the top end of the back rest (32), the reference point (R) will be at the same height position at the end of the combined movement than when where it was when said first or second input was transmitted. <t

N

O

N

>

LO

N

I

[an a <t

O

N

LO

0

N

O

N

CLATMS

1. A dental patient chair, comprising: - a seat part (31); - an elongated back rest (32) having a bottom end at a seat part end thereof and a top end at the opposite end; - a support structure of the seat part (35); - a first motorized construction (Ml) designed to enable altering a height position of the seat part (31) relative to the support structure of the seat part (35); - an articulated structure (A) connecting the seat part (31) and the back rest (32); - a second motorized construction (M2) designed to operate the articulated structure (A) to enable altering a tilt angle between the seat part (31) and the back rest (32); - a control system comprising a user interface configured to enable sending control commands to said first and second motorized con- structions (M1; M2); characterized in that the user interface is configured to enable transmitting a first and a second input to the control system, wherein said first input is designed to trigger a combination of operations comprising driving said first motorized con- struction (M1) to raise the seat part (31) and driving said second motorized construction (M2) to decrease the tilt angle, and said second input is designed to trigger a combination of operations comprising driving said first motorized con- struction (M1) to lower the seat part (31) and driving said second motorized construction (M2) to increase the tilt angle, and wherein both of the first and second inputs are configured to cause no other component optionally included in the patient chair construction to move, and wherein both of said combinations of operations generate such combined movement of the seat part (31)

and the back rest (32) that, considering a reference point (R) at a given short distance from the top end of the back rest (32), the reference point (R) will be at the same height position at the end of the combined movement than when where it was when said first or second input was transmitted. 2. A dental patient chair according to claim 1, characterized in that the control system is configured to calculate, when receiving said first or second input, a height position of the reference point (R) from a height position of the seat part (31) and a tilt angle of the back rest (32) at that moment. 3. A dental patient chair according to claim 2, characterized in that the dental patient chair comprises a first position sensor indicating a height position of the seat part (31) and a second position sensor indicating a tilt position of the back rest (32), wherein the first and second position sensors are optionally arranged to be a part of the first and second motorized construc- tions (M1, M2), and wherein the control system is configured to receive position signals from said first and second position sen- sors in response to receiving said first or second input.

Claims

STANDARD

1. A dental patient chair comprising: - a seat part (31); - an elongated backrest (32) having a lower end at the end of the seat part and an upper end at the opposite end; - a support structure for the seat part (35); - a first motorized structure (M1) designed to enable the height position of the seat part (31) to be changed relative to the support structure for the seat part (35); - a hinge structure (A) connecting the seat part (31) and the backrest (32); - a second motorized structure (M2) designed to use the hinge structure (A) to enable the tilt angle between the seat part (31) and the backrest (32) to be changed; - a control system comprising a user interface configured to enable control commands to be sent to said first and second motorized structures (M1; M2); characterized in that the user interface is configured to enable sending first and second inputs to the control system, said first input being designed to initiate a combination of functions comprising driving said first motorized structure (M1) to raise the seat part (31) and controlling said second motorized structure (M2) to decrease the tilt angle, and said second input being designed to trigger a combination of functions comprising driving said first motorized structure (M1) to lower the seat part (31) and controlling said second motorized structure (M2) to increase the tilt angle, and wherein both the first and second inputs are configured such that no other component optionally included in the patient chair structure can move, and wherein both said combinations of functions generate a combined movement of the seat part (31) and the backrest (32), taking into account a reference point (R) by a certain short distance from the end of the backrest (32), the reference point (R) is at the same height at the end of the combined movement as it was when said first or second input was sent.

2. A dental patient chair according to claim 1, characterized in that the control system is configured to calculate, upon receipt of said first or second input, the height position of the reference point (R) from the height position of the seat part (31) and the inclination angle of the backrest (32) at the current time.

3. A dental patient chair according to claim 2, characterized in that the dental patient chair comprises a first position sensor that indicates the height position of the seat part (31) and a second position sensor that indicates the tilt position of the backrest (32), wherein the first and second positioning sensors are optionally arranged as part of the first and second motorized structures (M1, M2), and wherein the control system is configured to receive position signals from said first and second position sensors in response to receiving said first or second input.