JP2020018465A - Dental unit - Google Patents

Abstract

To provide a dental unit which can be safely operated against a collision with a simpler configuration and can reduce misrecognition.SOLUTION: The dental unit comprises: a patient chair including a seat part movable vertically and a backrest capable of being tilted and erected with respect to the seat part; a sensor for detecting the posture of the backrest; and collision calculation means for calculating a collision of the backrest with an obstacle, from the result of an output from the sensor. The collision calculation means determines the presence or absence of a collision on the basis of the difference between the present posture of the backrest and the posture of the backrest at a previous time point, from the result of the output from the sensor.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a dental unit having a patient chair on which a patient sits in dentistry.

The dental unit is a unit provided with various facilities used for dental treatment, and includes a patient chair on which a patient sits. And around it, a doctor unit in which various instruments for dental treatment used by the practitioner are arranged, an assistant hanger equipped with various instruments mainly used by assistants, a water supply section for supplying gargling water to the patient, Spitton for draining the water, dental lighting for illuminating the oral cavity of the patient, and the like are provided. In addition, a chair on which a practitioner sits may be placed around the dental unit.
Here, the patient chair is configured to be able to move up and down and to be able to tilt and stand the backrest in order to bring the patient to a position that facilitates treatment and treatment.

  However, since the patient chair can be raised and lowered and tilted upright in this way, another object may be in its movable range, which may become an obstacle and collide. Such collisions should of course be avoided. Alternatively, even if a collision occurs, it is necessary to detect the collision and immediately stop raising and lowering and tilting the patient chair.

  Therefore, Patent Literature 1 discloses a technique in which a security switch is provided at three places between a backrest (backboard) and a seating portion (seatboard), an assistant holder, and a backrest. According to this, when the backrest moves in the tilting and rising direction, an abnormality can be detected by applying a force to the security switch. Patent Document 2 discloses a technique in which a plurality of predetermined regions around a dental unit (chair unit) are set as detection regions, and an obstacle is detected by a non-contact sensor in each region.

JP-A-7-96014 JP 2005-177131 A

In the techniques described in Patent Literatures 1 and 2, it is necessary to newly provide a security switch, a non-contact sensor, and the like in order to prevent a collision, which may lead to a complicated device.
In addition, when a non-contact type sensor is used as in Patent Literature 2, an obstacle is detected when a patient's chair moves up and down, and when an external force is applied due to, for example, movement of the patient during tilting and standing. In some cases, the patient's chair was stopped moving up and down and tilted upright. Since this is a safer operation, it may be possible, but it is an unnecessary stop from the viewpoint of the efficiency of a series of operations such as treatment, and it is desired to avoid it. If the frequency of unnecessary stoppages due to such erroneous recognition increases, the efficiency drops which cannot be ignored.

  In view of the above problems, an object of the present invention is to provide a dental unit that can operate safely in a collision with a simpler configuration and that can reduce false recognition.

  Hereinafter, the present invention will be described.

  One aspect of the present invention is a patient chair including a seating portion provided so as to be able to move up and down, and a backrest that can rotate and tilt and stand with respect to the seating portion, a sensor for detecting the posture of the backrest, and a sensor. Collision calculation means for calculating that the backrest has collided with the obstacle from the output result of the backrest, and the collision calculation means calculates, based on the output result from the sensor, the current posture of the backrest and the backrest at an earlier time. This is a dental unit that determines the presence or absence of a collision based on the difference between the posture of the dental unit.

  In the dental unit, the posture of the backrest may be the inclination angle of the backrest.

  ADVANTAGE OF THE INVENTION According to the dental unit of this invention, it can judge about a collision using the sensor for controlling back-and-forth raising / lowering, the attitude | position of a tilting up and down, and a structure becomes simple, Furthermore, the misperception regarding a collision is reduced and work efficiency falls. Can also be avoided.

FIG. 2 is an external perspective view of the dental unit 1. FIG. 2 is a plan view of the dental unit 1. FIG. 4 is a diagram illustrating a collision calculation unit 50. FIG. 4 is a diagram illustrating a collision calculation and a flow of control of the dental unit 10 based on the collision calculation.

  The present invention will be described based on an embodiment shown in the drawings. However, the present invention is not limited to these modes.

1 and 2 show the appearance of a dental unit 1 according to one embodiment. 1 is a perspective view, and FIG. 2 is a view seen from above.
The dental unit 1 includes a base 20, a patient chair 10, a dental lighting 2, an assistant unit 4, a doctor unit 30, and a collision calculating unit 50.

  The base 20 is arranged below the patient chair 10, and serves as a base of the patient chair 10. The base 20 has an outer shell formed by a housing, and various control devices are included inside the housing. Examples of the control device included therein include a hydraulic circuit for raising and lowering the patient chair 10, tilting and standing, and the like, and a hydraulic control unit for controlling the hydraulic circuit. Therefore, a foot switch 21 is provided on the back side of the patient chair 10 in the base 20, as shown in FIG. The practitioner operates the foot switch 21 and the operation switch on the operation panel 33 of the doctor unit 30 to issue a command to the hydraulic control means, and controls the hydraulic circuit to raise / lower the patient chair 10 and tilt it upright. Can be.

  Here, a linear potentiometer is arranged as a sensor in order to obtain the height position of the seating portion 11 of the patient chair 10 (the height position of the backrest 12) when controlling the elevation of the patient chair 10. In addition, when controlling the tilt of the backrest 12 of the patient chair 10, a rotary potentiometer is provided as a sensor in order to obtain a tilt angle of the backrest. As will be described later, these sensors are used not only for controlling the posture of the dental chair, but also for judging a collision with an obstacle.

  In this embodiment, the patient chair 10 includes a seating portion 11, a backrest 12, a headrest 13, a leg rest 14, and a footrest 15.

The seat 11 is mounted above the base 20 so as to be able to move up and down. The lifting and lowering of the seating portion 11 is performed by the hydraulic circuit housed in the base 20 as described above. Specifically, the practitioner operates the foot switch 21 and the operation panel 33 of the doctor unit 30 described later, and the hydraulic control means that receives the operation command appropriately operates the hydraulic cylinder incorporated in the hydraulic circuit. As a result, the seat 11 moves up and down. Then, the backrest 12, the headrest 13, the legrest 14, and the footrest 15 move up and down integrally with the seating portion 11.
At this time, the height position of the seating portion is detected by a sensor (seating portion sensor), whereby the height position is controlled. Although the type of the sensor used here is not particularly limited, for example, a linear potentiometer can be used.

The backrest 12 is a member that is rotatably provided around one end of the seating portion 11 and supports the torso of the patient. The backrest 12 can be tilted and raised so that the patient can be in a sitting position or a supine position. The tilting and standing of the backrest 12 is performed by a hydraulic circuit connected from within the base 20. Specifically, the operator operates the foot switch 21 and the operation panel 33 of the doctor unit 30, and the hydraulic control means that receives the operation instruction appropriately operates the hydraulic cylinder incorporated in the hydraulic circuit. The backrest 12 tilts and stands.
At this time, the inclination of the backrest 12 is controlled by a sensor (backrest sensor) detecting the inclination angle. The type of the sensor used here is not particularly limited, and examples thereof include a rotary potentiometer.

  The headrest 13 is a member disposed at an end of the end of the backrest 12 opposite to the side on which the seating portion 11 is disposed, and is a member that supports a patient's head. The headrest 13 is formed so as to be movable and rotatable so that the position of the patient's head is set to a posture convenient for the treatment. Such an operation of the headrest 13 is performed by a mechanism including a motor incorporated in the backrest 12. Specifically, the above-described mechanism that has received an operation command from a practitioner operating a switch (not shown) provided on the back side of the backrest 12 or the headrest 13 or an operation panel 33 of the doctor unit 30 to be described later is used. By operating, the headrest 13 moves and rotates.

  The leg rest 14 is a member that is rotatably provided around an end of the end of the seat 11 that is opposite to the side on which the backrest 12 is disposed, and supports the leg of the patient. Things. The leg rest 14 is rotatable so that the leg rest 14 can be in a vertical or horizontal posture in accordance with the posture of the backrest 12 being tilted and raised. Such rotation of the leg rest 14 is performed by a link mechanism that operates by linking to the tilting and standing of the backrest 12. Specifically, when the practitioner operates the foot switch 21 and the operation panel 33 of the doctor unit 30 as described above, the back rest 12 tilts and stands, and the leg rest 14 rotates in link with the tilt.

  The footrest 15 is a member provided to be movable in a direction in which the legrest 14 is extended from the legrest 14 and in a direction opposite to the direction, and supports the toe of the patient in a supine position. Specifically, in a posture in which the backrest 12 stands up, that is, in a sitting posture, the footrest 15 is overlapped with the legrest 14 and is not protruding. On the other hand, in a posture in which the backrest is tilted and the patient is turned on the back, the footrest 15 projects so as to extend the legrest 14 as shown in FIGS. As means for such movement of the footrest 15, a hydraulic pressure, a motor, a link mechanism, or the like can be used, but is not particularly limited.

  The dental lighting 2 is mounted via a freely movable and rotatable arm 3 by a universal joint or the like so that the interior of the patient's mouth can be accurately illuminated when performing treatment. Therefore, by adjusting the position and angle of the dental lighting device 2, it is possible to move the dental lighting device 2 to a position where the practitioner can appropriately observe the inside of the patient's mouth. The dental lighting 2 may be moved by hand or automatically moved by a gas spring or an air cylinder provided in the arm 3.

  The assistant unit 4 is provided on one side of the side of the patient chair 10, and includes an assistant hanger 5, a spitton 6, and a water supply device 7.

The assistant hanger 5 is a part provided with a device mainly used by the assistant. The assistant hanger 5 includes a hanger portion 5a and a hanger support 5b.
The hanger support 5b is a cylindrical (hollow column) member, and the lower end thereof is rotatably provided at the lower end of the assistant unit 4. The rotatable direction of the hanger support 5b is a rotation in a vertical plane around at least the lower end. However, rotation in a horizontal plane may be possible. The hanger part 5a is provided at the upper end of the hanger support 5b, and each device used by the assistant is suspended. The hanger part 5a is installed at the upper end of the hanger support 5b so as to be rotatable in a horizontal plane. Thereby, the hanger portion 5a is rotatable in the front-rear direction (vertical direction on the paper surface of FIG. 2) and can change its direction in a horizontal plane. Examples of the device suspended on the assistant hanger 5 include a handpiece such as a vacuum, a salivary duct, and a syringe. The vacuum and the salivary duct are connected to the vacuum unit via a suction pipe.

  The spittoon 6 is used when the patient gargles during treatment or after treatment with water supplied from the water supply unit 7 to wash the oral cavity. Therefore, the spittoon 6 is formed in a pot shape to discharge the water in the oral cavity after gargle. Then, the saliva and water discharged to the spitton 6 are discharged through a drain trap in the water unit. Here, the spittons 6 are rotatable in a horizontal plane toward the front side of the patient. As a result, the spittons 6 can be arranged in front of the patient, thereby improving convenience.

The doctor unit 30 is provided on a side opposite to the assistant unit 4 among the sides of the patient chair 10, and includes a work table 31, a first arm 40, and a second arm 45.
The workbench 31 is a part provided with tools, switches, and the like required by the practitioner. Specifically, the work table 31 has a work surface 31a on the upper surface thereof, and a handpiece group 32 used by a practitioner at the time of performing a treatment, and the work piece group 32 are stored at the rear end of the chair 10 for a patient. A holder is provided. Examples of the handpieces included in the handpiece group 32 include an air turbine, a micromotor, a scaler, a syringe, and the like. Almost all handpieces are connected to electrical circuits, water circuits, air circuits, etc., via tubing. An operation panel 33 is provided between the work surface 31a and the holder. The operation panel 33 is provided with various operation switches, and for example, can tilt and stand the patient chair 10, move up and down, and switch on and off the dental lighting 2.
In this way, the instruments and parts operated and handled by the practitioner are gathered on the workbench 31 on the back side of the patient chair 10. Thereby, the convenience of the practitioner who performs the procedure near the patient's head is achieved.

The first arm 40 is a so-called hollow rod-shaped arm member, one end of which is disposed below the base 20 and is rotatable in a horizontal plane. Therefore, the first arm 40 can rotate in the direction indicated by the arrow IIa in FIG.
The second arm 45 is also a hollow rod-shaped arm member. One end of the second arm 45 is disposed at the other end of the end of the first arm 40 that is opposite to the base 20 side. At the other end of the second arm 45, the worktable 31 is arranged.

The collision calculating means 50 monitors the height position of the dental chair 10 and the progress of the inclination angle of the backrest 12 to determine whether the dental chair 10 has collided with another device or member. A command to stop the movement and rotation of the chair is issued. At this time, the collision calculating means 50 is provided with a configuration for preventing the dental chair 10 from erroneously determining a collision when the dental chair 10 does not collide with another device or member, such as when the patient moves, It is possible to prevent the dental chair from being lifted and lowered and from being tilted upright due to misidentification. FIG. 3 conceptually shows the configuration of the collision calculating means 50.
As can be seen from FIG. 3, the collision calculation unit 50 includes an operator 51, a RAM 52, a storage unit 53, a reception unit 54, and an output unit 55.

  The operator 51 is configured by a so-called CPU (central operator), is connected to each of the above-described components, and is a unit that can control these components. The arithmetic unit 51 also executes various programs stored in the storage unit 53 or the like functioning as a storage medium, and performs arithmetic as a unit for generating various data or selecting data based on the various programs.

  The RAM 52 is a component that functions as a work area for the operator 51 and a storage unit for temporary data. The RAM 52 can be composed of an SRAM, a DRAM, a flash memory, or the like, and is similar to a known RAM.

  The storage unit 53 is a member that functions as a storage medium that stores programs and data that are the basis of various calculations. The storage means 53 may be capable of storing intermediate and final various results obtained by executing the program.

  In the present embodiment, one of the programs stored in the storage means 53 is to monitor the height position of the dental chair 10 and the progress of the inclination angle of the backrest 12 so that the dental chair 10 collides with another device or member. It includes a collision calculation for issuing a command to stop raising and lowering and tilting and raising the dental chair when it is determined that a collision has occurred, and determines whether there is a collision. At this time, the calculation includes a calculation for preventing the dental chair 10 from being erroneously determined as a collision when the dental chair 10 does not collide with another device or member, such as when the patient moves.

The calculation of such a collision determination can be performed, for example, in the following manner.
In the calculation of the collision determination according to the present embodiment, the posture of the backrest 12 is monitored while each part provided in the dental chair 10 is being lifted and lowered and tilted upright in accordance with a command to the dental chair 10. Then, in spite of the situation where the ascending and descending and the rising and standing should proceed according to the instruction, the ascending and descending that satisfies a predetermined condition described later, and the occurrence of the ascending and standing due to collision with the obstacle, the ascending and descending It is determined that the tilting and standing is inhibited.

  Specifically, the operation of the foot switch 21 or the doctor unit 30 instructs the dental chair 10 to move up and down and / or tilt upright, whereby the backrest 12 of the dental chair 10 rises and lowers and / or tilts upright. The average tilt angle of the backrest at the current time and the time before it, based on the output result from the sensor provided to control the vertical movement and the tilting and erecting while moving and turning It is determined whether or not the backrest 12 has collided with the obstacle based on the difference between the average backrest inclination angle and the average backrest angle. As a more specific example, in this embodiment, the calculation is performed as follows.

First, during the operation of raising and lowering the backrest and / or tilting and standing, posture information (tilt angle) of the backrest 12 is acquired at 0.05 second intervals from a sensor for controlling the tilting and standing of the backrest. Here, the inclination angle in the posture information is 0 ° when the backrest 12 is in the most inclined state, and is the maximum (for example, 90 °) when the backrest 12 is in the most vertically upright state. Accordingly, when the backrest 12 is deformed from the tilted state to the upright state, a change in the tilt angle occurs in the positive (+) direction, and when the backrest 12 is deformed from the upright state to the tilted state, it is negative (−). This means that the inclination angle changes in the direction.
When the posture information of the backrest is obtained by the rotary potentiometer as described above, the posture information is obtained as an output voltage at 0.05 second intervals, and is converted into an inclination angle. Thereby, the inclination angle of the backrest 12 is obtained every 0.05 seconds. This is stored as tilt angle information for one unit of the backrest 12. A method of converting the output voltage from the sensor into the tilt angle is known.

Next, the following three values are calculated for the inclination angle information of the backrest 12 based on the output result from the sensor obtained as described above.
(A) Current average tilt angle This is the average value of the tilt angle information for a total of 8 units of the current tilt angle information and the tilt angle information for the 7 units immediately before it.
(B) Average tilt angle 0.5 seconds before This is the average value of the tilt angle information for a total of 8 units of the tilt angle information 0.5 seconds before the present and the tilt angle information for the 7 units immediately before the current. is there.
(C) Average tilt angle 1.0 seconds before This is the average value of the tilt angle information for a total of 8 units of the tilt angle information 1.0 seconds before the present and the tilt angle information for 7 units immediately before the current. is there.

  Here, when the posture information of the backrest is obtained by the rotary potentiometer, since the inclination angle information is obtained as described above, (A) to (C) are represented by angles (°).

Then, the following determination conditions are calculated to determine whether there is a collision due to an obstacle.
(1) In the case where the backrest is only tilted: “current average tilt angle” − “average tilt angle 0.5 seconds ago” ≧ −0.065 °
(2) In the case of an operation in which the backrest tilts and descends, “current average inclination angle” − “average inclination angle before 0.5 seconds” ≧ −0.065 °
(3) In the case of only the operation of lowering the backrest “Current average inclination angle” − “Average inclination angle 1.0 seconds ago” ≧ 0.65 °

If there is a change in the posture of the backrest (change in the average tilt angle) in the range of (1) to (3), it is determined that there is a collision with an obstacle, and the dental chair is lowered and / or tilted is stopped. I do.
On the other hand, when there is a change in the posture of the backrest (change in the average inclination angle) outside the range of (1) to (3), whether the dental chair has been properly deformed properly, or It is determined that such a change is not due to a collision but due to other causes such as movement of the patient, and the lowering and / or tilting of the dental chair is not stopped.
By performing such a calculation, inappropriate stoppage can be avoided, and a decrease in treatment efficiency can be suppressed.

The above (1) to (3) will be described in more detail as follows.
In the case of “(1) only the operation of tilting the backrest”, while the backrest 12 is rotating in the negative (−) direction, “current average tilt angle” − “average tilt angle 0.5 seconds ago” Is less than -0.065 °, the degree of rotation (tilt) is small, or rotation in the opposite (positive) direction, though it should be rotated in the negative direction. Means to do. Therefore, at this time, since the tilt of the backrest is hindered, it can be considered that the vehicle has collided with the obstacle.
On the other hand, an angle change in which this is smaller than -0.065 °, that is, a change in which the tilt is sharper, means that the tilt of the backrest is progressing normally, or a change in the tilt angle normally performed by the dental unit. It is unlikely that a collision with an obstacle will occur even if it exceeds the range, and it is conceivable that the patient sitting on the dental chair 10 may have moved. Therefore, it is not necessary to stop the deformation of the dental chair.
(2) can be similarly considered.

In the case of “(3) only the operation of lowering the backrest”, while “the tilt angle of the backrest 12 does not change”, ““ the current average tilt angle ”−“ the average tilt angle before 1.0 second ”” is 0. When a change of .65 ° or more is made, it means that the backrest is largely rotated in the direction in which the backrest stands, although there is no change originally. Therefore, at this time, since the lowering of the backrest (dental chair) is hindered, it can be considered that the vehicle has collided with the obstacle.
On the other hand, an angle change of less than 0.65 °, that is, a small change in the upright direction or a change in the tilting direction is caused by an obstacle even if the tilt angle originally does not change. It is unlikely that this is due to the collision of the patient, and it is possible that the patient sitting on the dental chair 10 has moved, so it is not necessary to stop the deformation of the dental chair.

  In this embodiment, specific items have been described with specific numerical values for simplicity. However, these numerical values are not limited to this example, and various numerical values can be appropriately set as needed. That is, in determining whether the backrest has collided with the obstacle, it is determined whether the backrest 12 has collided with the obstacle based on the difference between the current tilt angle of the backrest and the tilt angle of the backrest before that. It suffices if an operation is included.

In the present embodiment, the determination of the presence or absence of a collision is made only for the backrest. This is because the backrest has a high possibility of colliding with an obstacle, and is a member that rapidly moves in response to an external force such as movement of a patient. However, the present invention is not limited to this, and it may be configured to similarly determine whether there is a collision with other members provided in the dental chair.
Further, in the present embodiment, the determination of the presence or absence of a collision targets only the lowering of the backrest and / or the tilting of the backrest elevating and the tilting upright. This is because it is difficult to assume that the backrest stands and / or rises and / or collides with other members in the first place, and it is not always necessary to determine whether there is a collision. However, the present invention is not limited to this, and it may be determined whether or not there is a collision with respect to all of the elevation of the backrest and / or the tilting and standing.

  The receiving means 54 is a component having a function of appropriately taking in information from the outside into the collision calculating means 50, and is connected to at least a sensor provided in the patient chair.

  The output unit 55 is a component having a function of appropriately outputting information to be output to the outside of the obtained result, and is connected to the hydraulic control unit in the present embodiment. Accordingly, when the collision calculating means 50 determines that the patient chair 10 has collided with another member or the like, a command is issued to the hydraulic control means to stop the movement and rotation of the patient chair 10.

  Next, a description will be given of the permissibility and regulation of raising and lowering and tilting of the patient chair 10 by the collision calculating means 50. FIG. 4 shows the flow. As can be seen from FIG. 4, the calculation by the collision calculation means 50 includes steps S11 to S17. Hereinafter, each process will be described.

  In the step S11, a command for deformation (elevation, tilting and standing) of the dental chair 10 is issued. Such a deformation command is issued by, for example, the foot switch 21 or the doctor unit 30 as described above.

  In step S12, posture information of the backrest 12 of the dental chair 10 is obtained. The posture of the backrest 12 is determined by the sensor arranged on the dental chair 10 as described above. In this embodiment, such posture information is acquired and accumulated every 0.05 seconds (0.05 seconds from step S12 until information is acquired again in step S12).

  In step S13, a condition is calculated for making the above-described determination on the collision. More specifically, in the present embodiment, the respective left sides of (1) to (3) are calculated.

In step S14, a determination is made on the calculation performed in step S13 under the above-described conditions (1) to (3).
If the condition is satisfied, it is determined that this is a collision, Yes is selected, the process proceeds to step S15, the deformation of the dental chair is stopped, and the process ends.
On the other hand, when the condition is not satisfied, there is no collision, and it is assumed that the dental chair has moved due to normal deformation or some other cause other than the collision, No is selected, and the process proceeds to step S16 to deform the dental chair. Is continued.

In step S17, after the deformation of the dental chair is continued in step S16, it is determined whether the deformation originally planned is completed.
If the deformation originally planned is completed, Yes is selected and the process ends.
On the other hand, if the deformation originally planned is not yet completed, No is selected and the process returns to step S12.

  As described above, according to the dental unit 1 provided with the collision calculation means 50, it is possible to reduce erroneous recognition in determining a collision, to suppress a malfunction of stopping the patient chair due to a cause other than the collision, and to suppress a decrease in treatment efficiency. It is possible. The determination of such a collision can be made using a sensor for controlling the posture of the dental chair, and there is no need to provide additional sensors for detecting obstacles. It can be.

DESCRIPTION OF SYMBOLS 1 Dental unit 2 Dental lighting 3 Arm 4 Assistant unit 5 Assistant hanger 5a Hanger part 5b Hanger support 6 Spiton 7 Water supply device 10 Patient chair 11 Seating part 13 Headrest 14 Legrest 15 Footrest 20 Base 21 Foot switch 30 Doctor unit 31 Work table 31a Work surface 32 Hand piece group 33 Operation panel 40 First arm 45 Second arm 50 Collision calculation means 51 Operator 52 RAM
53 storage means 54 receiving means 55 output means

Claims (2)

A chair provided with a seating portion provided so as to be able to ascend and descend, and a backrest that can rotate and tilt and stand with respect to the seating portion;
A sensor for detecting the posture of the backrest,
Collision calculation means for calculating from the output result of the sensor that the backrest has collided with an obstacle,
The dental unit, wherein the collision calculating means determines the presence or absence of the collision based on a difference between a current posture of the backrest and a posture of the backrest before that based on an output result from the sensor.   The dental unit according to claim 1, wherein the posture of the backrest is an inclination angle of the backrest.

Images