CN212435611U

CN212435611U - Dental chair motor control circuit and dental chair

Info

Publication number: CN212435611U
Application number: CN202021771396.7U
Authority: CN
Inventors: 崔文宝; 杨华
Original assignee: Best Deyou Medical Equipment Guangzhou Co ltd
Current assignee: Best Deyou Medical Equipment Guangzhou Co ltd
Priority date: 2020-06-16
Filing date: 2020-08-21
Publication date: 2021-01-29
Anticipated expiration: 2030-08-21
Also published as: CN111917345A

Abstract

The utility model provides a dental chair and dental chair motor control circuit thereof, including motor, monolithic microcontroller, and connect in monolithic microcontroller with H bridge drive circuit between the motor, H bridge drive circuit include H bridge driver chip, with the input connection's of motor first switch tube and second switch tube and with the output connection's of motor third switch tube and fourth switch tube.

Description

Dental chair motor control circuit and dental chair

Technical Field

The utility model relates to a medical equipment field, in particular to dental chair motor control circuit and dental chair.

Background

A dental comprehensive treatment machine is called a dental chair for short, which is a comprehensive treatment table used by stomatologists for oral examination, treatment and operation of patients. The dental chair is required to be used as a comprehensive treatment table and has the functions of adjusting the body position, the posture, the height and the like of a patient during treatment and operation. These regulation functions require motor output action and are controlled.

In the known technology, the motor control of the dental chair controls the on-off of a current power supply through a relay, so that the control of starting, stopping and positive and negative rotation of the motor is realized. However, the relay generates heat when operating, the longer the power-on time is, the more serious the heat is, and the mechanical contact is used for realizing the control of the relay, and the phenomena of mechanical abrasion, arc burning and the like exist when the contact is opened and closed, so the contact has short service life, and the reliability and the maintainability are poor.

SUMMERY OF THE UTILITY MODEL

In order to solve the existing technical problem, the utility model provides a dental chair motor control circuit and dental chair with higher reliability and maintainability.

In order to achieve the above object, the embodiment of the present invention provides a technical solution that:

the utility model provides a dental chair motor control circuit, includes motor and single chip microcontroller, still including connect in single chip microcontroller with H bridge drive circuit between the motor, H bridge drive circuit include H bridge driver chip, with the first switch tube and the second switch tube of the input connection of motor and with the third switch tube and the fourth switch tube of the output connection of motor.

The H-bridge driving chip is a half-bridge driving chip.

The control circuit further comprises an overcurrent protection circuit connected between the H-bridge drive circuit and the single-chip microcontroller.

The overcurrent protection circuit comprises a sampling resistor connected between the second switching tube and the fourth switching tube and a power ground, and a current detection amplifier connected with two ends of the sampling resistor.

The control circuit board comprises a display module, and the display module adopts a 4-digit digital tube for output.

The control circuit comprises a communication module, and the communication module exchanges signals and data with the outside by adopting an RS485 communication protocol.

Wherein the control circuit comprises two single-chip microcontrollers ATMEGA16 and ATMEGA 32.

Wherein, the two single-chip microcontrollers adopt synchronous serial peripheral interface protocol communication before.

Wherein the two monolithic microcontrollers comprise: the first single-chip microcontroller outputs signals to control the H-bridge circuit driving chip and the key board input circuit; and the second single-chip microcontroller is used for acquiring signals, controlling the output signals of the electromagnetic valve and driving a nixie tube.

A dental chair comprises the dental chair motor control circuit.

The embodiment of the utility model provides a dental chair and dental chair control circuit includes following advantage at least:

1) an H-bridge driving circuit is connected between the single-chip microcontroller and the motor, the H-bridge driving circuit comprises two groups of switches which are respectively connected with two ends of the motor, the single-chip microcontroller drives the motor to start and stop and control forward and backward through the H-bridge driving circuit, so that an electronic element non-contact switch is adopted to replace a mechanical relay switch to contact, the phenomena of mechanical abrasion, electric arc burning and the like of the mechanical contact switch are avoided, and the reliability and the maintainability are improved;

2) the H-bridge driving circuit is adopted to control the motor, the PWM speed regulation function of the motor can be realized, the motor can be slowly started and stopped, and the comfort level of a patient during treatment is greatly improved.

Drawings

FIG. 1 is a schematic diagram of a motor drive circuit for a known dental chair;

FIG. 2 is a schematic diagram of a motor control circuit for a dental chair according to an embodiment of the present application;

fig. 3 is a schematic diagram of a motor control circuit for a dental chair according to another embodiment of the present application.

Detailed Description

The technical solution of the present application is further described in detail with reference to the drawings and specific embodiments of the specification.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of implementations of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

In the description of the present invention, it is to be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are merely for convenience of description and simplicity of description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, are not to be construed as limiting the present invention. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

The prior dental chair adopts a single-chip microcontroller in a control system, and adopts a relay to control the running, positive and negative rotation of a motor in the control output of the motor. As shown in fig. 1, the schematic diagram of a control circuit of a motor of a known dental chair is shown, wherein a single-chip microcontroller is connected with two control ends of the motor through a first relay and a second relay respectively, and a direct current motor controls the on-off of a direct current power supply through the relays to realize the on-off, positive and negative rotation control of the motor. In the known control scheme, the relay can generate heat when working, and the longer the power-on time is, the more serious the heat generation is; meanwhile, the relay control system uses mechanical contacts, and when the contacts are opened and closed, the phenomena of mechanical abrasion, arc burning and the like exist, and the service life of the contacts is short, so that the reliability and the maintainability are poor.

In order to solve the above problem, embodiments of the present application provide a dental chair control circuit and a dental chair motor control circuit. Referring to fig. 2, a schematic diagram of a dental chair control circuit provided in an embodiment of the present application is shown, where the dental chair control circuit includes a motor M, a single-chip microcontroller, and an H-bridge driving circuit connected between the single-chip microcontroller and the motor M, and the H-bridge driving circuit includes an H-bridge driving chip 102, a first switching tube T1 and a second switching tube T2 connected to an input of the motor M, and a third switching tube T3 and a fourth switching tube T4 connected to an output of the motor M.

In the embodiment, an H-bridge driving circuit is connected between the single-chip microcontroller and the motor M, the H-bridge driving circuit comprises two groups of switches respectively connected with two ends of the motor M, the single-chip microcontroller drives the motor M to start and stop and control forward and reverse rotation through the H-bridge driving circuit, and the mechanical relay switch contact is replaced by adopting an electronic element non-contact switch, so that the phenomena of mechanical abrasion, arc burning and the like of the mechanical contact switch are avoided, and the reliability and the maintainability are improved; the H-bridge driving circuit is adopted to control the motor M, the PWM speed regulation function of the motor M can be realized, the motor M can be slowly started and stopped, and the comfort level of a patient during treatment is greatly improved.

In some embodiments, in combination with the dental chair control circuit shown in fig. 3, the single-chip microcontroller comprises a first single-chip microcontroller 101 for outputting signals to control the H-bridge circuit driver chip and the keypad input circuit; and the second single-chip microcontroller 102 is used for collecting signals, controlling the output signals of the electromagnetic valve and driving a nixie tube. Optionally, the first single-chip microcontroller 101 controls the motor M through an H-bridge driving circuit to form a dental chair motor control circuit. In an alternative embodiment, the T1, T2, T3 and T4, which are N-channel enhancement mode fets, all function as switches. The first switch tube T1, the second switch tube T2, the third switch tube T3 and the fourth switch tube T4 constitute a switch and commutation circuit 103 connected between the H-bridge driving chip 102 and the motor M.

In some embodiments, the H-bridge driver chip 102 is a half-bridge driver chip. As an alternative specific example, the H-bridge driver chip 102 may adopt a special half-bridge driver chip with model number IR 2103S. The output end of the H-bridge driving chip 102 is respectively connected with the grid electrodes of the field effect transistors, the first field effect transistor and the second field effect transistor which are connected with one end of the motor M are in a symmetrical state relative to the third field effect transistor and the fourth field effect transistor which are connected with the other end of the motor M, the drain electrodes of the first field effect transistor and the third field effect transistor are respectively connected with a driving power supply of the motor M, and the source electrodes of the second field effect transistor and the fourth field effect transistor are respectively connected with the ground. The first single-chip microcontroller 101 controls the field effect transistor to switch between on and off through the H-bridge control chip, so as to control the start, stop, forward rotation and reverse rotation of the motor M. As an alternative embodiment, the FET may be an N-channel enhancement FET of type NCE80H11, NCE80H12 or IRF 3205.

The control circuit of the dental chair motor M provided by the above embodiment has the advantages of at least comprising: an H-bridge driving circuit is connected between the first single-chip microcontroller 101 and the motor M, the H-bridge driving circuit comprises two groups of switches which are respectively connected with two ends of the motor M, the first single-chip microcontroller 101 realizes starting and stopping and forward and reverse rotation control of the motor M through the H-bridge driving circuit, and an electronic element non-contact switch is adopted to replace a mechanical relay switch to contact and control the motor M, so that the phenomena of mechanical abrasion, electric arc burning and the like of a mechanical contact switch are avoided, and the reliability and the maintainability are improved; the H-bridge driving circuit is adopted to control the motor M, the speed regulation function of PWM of the motor M can be realized, the motor M can be slowly started and stopped, and the comfort level of a patient during treatment is greatly improved.

In some embodiments, the control circuit further comprises an over-current protection circuit connected between the H-bridge driver circuit and the first monolithic microcontroller 101. The overcurrent protection circuit comprises a sampling resistor 105 connected between the second switching tube T2 and the fourth switching tube T4 and the power ground, and a current detection amplifier 104 connected with two ends of the sampling resistor 105. Taking the switching tubes as field effect tubes, the sampling resistor 105 is connected between the source of the second field effect tube and the source of the fourth field effect tube and the ground, and the current detection amplifier 104 is connected to two ends of the sampling resistor 105. The current detection amplifier 104 can detect the current signal flowing through the sampling resistor 105 and amplify and provide the current signal to the first monolithic microcontroller 101, so that the first monolithic microcontroller 101 can judge the overcurrent state of the motor M according to the current signal provided by the current detection amplifier 104, and perform corresponding control based on the overcurrent state of the motor M.

In some embodiments, the control circuit includes a display module that employs a 4-bit digital tube output.

In some embodiments, the control circuit comprises a communication module, and the communication module exchanges signals and data with the outside by adopting an RS485 communication protocol.

In some embodiments, the two monolithic microcontrollers are microcontrollers, respectively model ATMEGA16, ATMEGA 32. The two single-chip microcontrollers communicate with each other by using an SPI (synchronous Peripheral Interface) communication protocol. The first single-chip microcontroller is used for outputting signals to control the H-bridge circuit driving chip and the key board input circuit; and the second single-chip microcontroller is used for collecting signals, controlling the output signals of the electromagnetic valve and driving the nixie tube. As an optional specific example, the first monolithic microcontroller 101 controls start and stop and forward and reverse rotation switching of the motor M, the second monolithic microcontroller 201 is connected to a signal acquisition circuit 202, a nixie tube driving circuit 203 and an electromagnetic valve output circuit 204, the second monolithic microcontroller 201 is connected to a signal acquisition element of the dental chair through the signal acquisition circuit 202, the electromagnetic valve output circuit 204 is connected to a control electromagnetic valve, and the nixie tube driving circuit 203 is connected to a display module. The signal acquisition element can be an electronic element used for acquiring the working state of the dental chair in various circuits, such as a sensor, a thermistor and the like. The display module is used for displaying working parameters, working states and the like of the dental chair and can be a display screen comprising a nixie tube and the like. The first microcontroller chip 101 and the second microcontroller chip 201 may be mutually a main processor and a secondary processor.

In some embodiments, the control circuit further includes a voltage boost circuit connected to the H-bridge driver chip 102, and may provide the H-bridge driver chip 102 with a higher voltage requirement and a lower voltage requirement respectively in a use state where the driving motor M is switched between forward and reverse rotation, so as to reduce power consumption and improve efficiency.

The boost circuit for providing power to the H-bridge driving circuit provided by the above embodiments has at least the following advantages: the power supply circuit is simplified, and one transformer is omitted when the main power supply is output; the voltage is boosted to 40-45V by the power supply booster, so that the stability of voltage output is improved.

The above description is only for the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto, and any person skilled in the art can easily think of the changes or substitutions within the technical scope of the present invention, and all should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. The utility model provides a dental chair motor control circuit, includes motor and single chip microcontroller, its characterized in that, still including connect in single chip microcontroller with H bridge drive circuit between the motor, H bridge drive circuit include H bridge driver chip, with the first switch tube and the second switch tube of the input connection of motor and with the third switch tube and the fourth switch tube of the output connection of motor.

2. The dental chair motor control circuit of claim 1, wherein the H-bridge driver chip is a half-bridge driver chip.

3. The dental chair motor control circuit of claim 1, further comprising an over-current protection circuit connected between the H-bridge drive circuit and the monolithic microcontroller.

4. The motor control circuit of claim 3, wherein the over-current protection circuit comprises a sampling resistor connected between the second switching tube and the fourth switching tube and a power ground, and a current sense amplifier connected to both ends of the sampling resistor.

5. The dental chair motor control circuit of claim 1, wherein the control circuit further comprises a display module, the display module using a 4-digit digitizer for output.

6. The motor control circuit of the dental chair of claim 1, wherein the control circuit comprises a communication module, and the communication module exchanges signals and data with the outside by adopting an RS485 communication protocol.

7. The dental chair motor control circuit of claim 1, wherein the control circuit comprises two single-chip microcontrollers, ATMEGA16, ATMEGA32, respectively.

8. The dental chair motor control circuit of claim 7, wherein the two monolithic microcontrollers communicate using a synchronous serial peripheral interface protocol.

9. The dental chair motor control circuit of claim 7, wherein the two single-chip microcontrollers comprise: the first single-chip microcontroller outputs signals to control the H-bridge circuit driving chip and the key board input circuit; and the second single-chip microcontroller is used for acquiring signals, controlling the output signals of the electromagnetic valve and driving a nixie tube.

10. A dental chair comprising a dental chair motor control circuit as claimed in any one of claims 1 to 9.