阅读说明：本技术 电动转台控制系统及其控制方法 (Electric turntable control system and control method thereof ) 是由 谢光勤 于 2021-03-17 设计创作，主要内容包括：本发明公开了一种电动转台控制系统,包括第一接近开关、第二接近开关、主控以及用于控制步进电机运行的步进电机控制芯片；第一接近开关、第二接近开关以及步进电机控制芯片均与主控信号连接；转台周向间隔布置有传感位置,传感位置包括触发位置和非触发位置,每个触发位置和每个非触发位置的间隔相等且交替设置；第一接近开关和第二接近开关依次沿转台的顺时针旋转方向设置,第一接近开关和第二接近开关间隔一个传感位置。本发明主要解决电动转台之电机控制技术中存在的一系列问题；通过传感器与触发位置和非触发位置的配合,即可实现电动转台的启停、正反转和加减速功能,其功能完善,且不需要任何遥控器和硬件开关等外部控制机构,利于清洁。(The invention discloses an electric turntable control system which comprises a first proximity switch, a second proximity switch, a master control and a stepping motor control chip for controlling the operation of a stepping motor, wherein the first proximity switch is connected with the master control; the first proximity switch, the second proximity switch and the stepping motor control chip are all connected with the master control signal; sensing positions are circumferentially arranged at intervals on the rotary table, the sensing positions comprise triggering positions and non-triggering positions, and the intervals of the triggering positions and the non-triggering positions are equal and are alternately arranged; the first proximity switch and the second proximity switch are sequentially arranged along the clockwise rotation direction of the rotary table, and the first proximity switch and the second proximity switch are spaced by a sensing position. The invention mainly solves a series of problems in the motor control technology of the electric turntable; the functions of starting, stopping, forward and reverse rotation and acceleration and deceleration of the electric turntable can be realized by matching the sensor with the triggering position and the non-triggering position, the functions are complete, no external control mechanism such as a remote controller and a hardware switch is needed, and the cleaning is facilitated.)

1. An electric turntable control system is applied to an electric turntable, the electric turntable comprises a turntable and a stepping motor, the turntable is driven by the stepping motor and can rotate along a clockwise direction or an anticlockwise direction, and the electric turntable control system is characterized in that,

the control device comprises a first proximity switch, a second proximity switch, a master control and a stepping motor control chip for controlling the operation of a stepping motor; the first proximity switch, the second proximity switch and the stepping motor control chip are all connected with the master control signal;

sensing positions are circumferentially arranged at intervals on the rotary table, the sensing positions comprise triggering positions and non-triggering positions, and the intervals of the triggering positions and the non-triggering positions are equal and are alternately arranged; the first proximity switch and the second proximity switch are sequentially arranged along the clockwise rotation direction of the rotary table, and the first proximity switch and the second proximity switch are separated by one sensing position.

2. The electric turntable control system of claim 1, wherein: the main control unit is a micro control unit.

3. The electric turntable control system of claim 2, wherein: the first proximity switch and the second proximity switch are in signal connection with the universal input/output pin of the master control.

4. The electric turntable control system of claim 2, wherein: and an ENN pin, a STEP pin and a DIR pin of the stepping motor control chip are in signal connection with the master control general input/output pin.

5. The electric turntable control system of claim 1, 2 or 4, wherein: an OA1 pin of the stepping motor control chip is connected with a port 1 of a winding A of the stepping motor, an OA2 pin of the stepping motor control chip is connected with a port 2 of the winding A of the stepping motor, an OB1 pin of the stepping motor control chip is connected with a port 1 of a winding B of the stepping motor, and an OB2 pin of the stepping motor control chip is connected with a port 2 of the winding B of the stepping motor.

6. The electric turntable control system of claim 1, wherein: the stepping motor control chip is used for controlling the stepping motor to run.

7. A method for controlling an electric turntable, to which the electric turntable control system according to any one of claims 1 to 6 is applied, comprising the steps of:

s1, the main control detects whether the first proximity switch and the second proximity switch send out trigger signals at the same time; if yes, go to step S2; if not, the stepping motor is closed;

s2, the master control detects signals sent by the first proximity switch and the second proximity switch; if the first proximity switch sends a trigger signal and the second proximity switch sends a non-trigger signal, the stepping motor is controlled to drive the rotary table to rotate anticlockwise; if the second proximity switch sends a trigger signal and the first proximity switch sends a non-trigger signal, the stepping motor is controlled to drive the rotary table to rotate clockwise;

s3, the step S1 is executed continuously.

8. The electric turntable control method according to claim 7, characterized in that: after step S2, the method further includes:

when the stepping motor drives the rotary table to rotate anticlockwise, if the first proximity switch accelerates to send a trigger signal and the second proximity switch accelerates to send a non-trigger signal, the stepping motor is controlled to rotate anticlockwise in an accelerated manner;

when the stepping motor drives the rotary table to rotate clockwise, if the second proximity switch accelerates to send a trigger signal, and the first proximity switch accelerates to send a non-trigger signal, the stepping motor is controlled to rotate clockwise in an accelerated mode.

9. The electric turntable control method according to claim 7 or 8, characterized in that: after the running state of the stepping motor is changed every time, the changed running state of the stepping motor is stored in a main control memory;

and when the main control is started, the stepping motor is driven to operate in the operating state stored in the memory.

Technical Field

The invention relates to the technical field of electromechanical control, in particular to a control system and a control method of an electric turntable.

Background

At present, many high-end dining tables all adopt an electric turntable, the electric turntable commonly used comprises a turntable and a motor, the turntable is driven by the motor to rotate, and the motor control method of the electric turntable mainly comprises the following three steps:

1. and (3) adopting hardware switch control: the motor is powered on by closing the switch, the rotary table rotates, the motor is powered off by opening the switch, and the rotary table stops rotating;

2. and (3) controlling by adopting a sensor: detecting the state of the turntable using, for example, an infrared sensor or a capacitance sensor; when the motor stops, a person stirs the rotary table to enable the sensor to send a signal, and the master control controls the motor to start rotating; when the motor runs, a person presses the rotary table to enable the sensor to send a signal, and the main control controls the motor to stop rotating;

3. and (3) adopting a remote controller to control: the remote controller is adopted to send various signals to the main controller, and the main controller further controls the motor to correspondingly operate, such as starting and stopping, forward and reverse rotation and acceleration and deceleration of the motor.

The three motor control methods all have the following disadvantages: when the hardware switch is adopted for control, a switch needs to be installed on the dining table, the appearance of the dining table is affected, the cleaning is not facilitated, and the functions are single; when the sensor is adopted for control, the function is still single; when the remote controller is used for control, the battery of the remote controller needs to be replaced from time to time, and the remote controller is easy to lose.

In summary, a control system and a control method for an electric turntable are needed to solve a series of problems in the prior art.

Disclosure of Invention

One of the purposes of the invention is to provide a control system of an electric turntable, which enables the electric turntable to realize the functions of starting and stopping, forward and reverse rotation and acceleration and deceleration.

The invention also aims to provide a control method of the electric turntable, which is used in cooperation with a control system of the electric turntable to enable the electric turntable to realize the functions of starting and stopping, forward and reverse rotation and acceleration and deceleration.

In order to achieve the purpose, the invention provides the following technical scheme: an electric turntable control system is applied to an electric turntable, the electric turntable comprises a turntable and a stepping motor, the turntable is driven by the stepping motor and can rotate in a clockwise or anticlockwise direction, and the electric turntable comprises a first proximity switch, a second proximity switch, a master control chip and a stepping motor control chip for controlling the operation of the stepping motor; the first proximity switch, the second proximity switch and the stepping motor control chip are all connected with the master control signal; sensing positions are circumferentially arranged at intervals on the rotary table, the sensing positions comprise triggering positions and non-triggering positions, and the intervals of the triggering positions and the non-triggering positions are equal and are alternately arranged; the first proximity switch and the second proximity switch are sequentially arranged along the clockwise rotation direction of the rotary table, and the first proximity switch and the second proximity switch are separated by one sensing position.

In the above technical solution, the main control is a micro control unit.

In the above technical solution, the first proximity switch and the second proximity switch are both in signal connection with the general input/output pin of the main control.

In the above technical solution, the ENN pin, the STEP pin, and the DIR pin of the stepper motor control chip are all in signal connection with the master general input/output pin.

In the above technical solution, the OA1 pin of the stepping motor control chip is connected to port 1 of the winding a of the stepping motor, the OA2 pin of the stepping motor control chip is connected to port 2 of the winding a of the stepping motor, the OB1 pin of the stepping motor control chip is connected to port 1 of the winding B of the stepping motor, and the OB2 pin of the stepping motor control chip is connected to port 2 of the winding B of the stepping motor.

In the above technical solution, the electric turntable control system further includes a power supply module for supplying power to the main control and the stepping motor control chip.

A control method of an electric turntable applies the control system of the electric turntable, and comprises the following steps:

s1, the main control detects whether the first proximity switch and the second proximity switch send out trigger signals at the same time; if yes, go to step S2; if not, the stepping motor is closed;

s2, the master control detects signals sent by the first proximity switch and the second proximity switch; if the first proximity switch sends a trigger signal and the second proximity switch sends a non-trigger signal, the stepping motor is controlled to drive the rotary table to rotate anticlockwise; if the second proximity switch sends a trigger signal and the first proximity switch sends a non-trigger signal, the stepping motor is controlled to drive the rotary table to rotate clockwise;

s3, the step S1 is executed continuously.

In the above technical solution, after step S2, the method further includes: when the stepping motor drives the rotary table to rotate anticlockwise, if the first proximity switch accelerates to send a trigger signal and the second proximity switch accelerates to send a non-trigger signal, the stepping motor is controlled to rotate anticlockwise in an accelerated manner; when the stepping motor drives the rotary table to rotate clockwise, if the second proximity switch accelerates to send a trigger signal, and the first proximity switch accelerates to send a non-trigger signal, the stepping motor is controlled to rotate clockwise in an accelerated mode.

In the above technical solution, after the operation state of the stepping motor is changed each time, the changed operation state of the stepping motor is stored in the main control memory; and when the main control is started, the stepping motor is driven to operate in the operating state stored in the memory.

Compared with the prior art, the invention has the beneficial effects that:

1. this kind of electronic revolving stage control system, the sensing position is including trigger position and non-trigger position, every trigger position equals and sets up in turn with every non-trigger position's interval, first proximity switch and second proximity switch set up along the clockwise rotation direction of revolving stage in proper order, and sensing position of first proximity switch and second proximity switch interval, cooperation through sensor and trigger position and non-trigger position, can realize opening of electronic revolving stage and stop, positive and negative rotation and acceleration and deceleration function, its function is perfect, and do not need external control mechanism such as any remote controller and hardware switch, do benefit to the cleanness.

2. According to the control method of the electric turntable, the starting, stopping, forward and reverse rotation and acceleration and deceleration functions of the electric turntable can be realized by detecting signals of the first proximity switch and the second proximity switch, the functions are complete, no external control mechanism such as a remote controller and a hardware switch is needed, and the cleaning is facilitated.

Drawings

Fig. 1 is a perspective view of a power turntable to which the present invention is applied.

Fig. 2 is an exploded view of a power turntable to which the present invention is applied.

Fig. 3 is a perspective view of a power turret with the turret removed, to which the present invention is applied.

Fig. 4 is a partially enlarged view of a in fig. 3.

Fig. 5 is a schematic circuit diagram of the electric turntable control system according to the present invention.

Fig. 6 is a schematic diagram of a partial circuit of the master control in the present invention.

Fig. 7 is a partial circuit schematic diagram of the stepping motor control chip in the present invention.

Fig. 8 is a partial circuit schematic diagram of the power supply module of the present invention.

Fig. 9 is a schematic view of a power turntable to which the present invention is applied when rotating counterclockwise.

Fig. 10 is a schematic view of a power turntable to which the present invention is applied when rotating clockwise.

The reference signs are: 1. a turntable; 2. a stepping motor; 3. a drive ring; 4. a bearing; 5. a gear; 6. a first proximity switch; 7. a second proximity switch; 8. an induction loop; 81. a rib; 82. a groove; 91. a trigger position; 92. a non-triggered position.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1 to 4, the present invention provides an electric turntable control system, which is applied to an electric turntable, the electric turntable includes a turntable 1 and a stepping motor 2, the turntable 1 is driven by the stepping motor 2 and can rotate in a clockwise or counterclockwise direction; a transmission ring 3 with internal teeth is fixed on the bottom surface of the rotary table 1, the transmission ring 3 is coaxial with the rotary table 1, the transmission ring 3 is supported on a plane through a bearing 4, the stepping motor 2 is arranged in an inner ring of the transmission ring 3, a gear 5 is sleeved on a rotating shaft of the stepping motor 2, and the gear 5 of the stepping motor 2 and the transmission ring 3 of the rotary table 1 are transmitted through another gear 5, so that the rotary table 1 is driven to rotate; in other possible embodiments, the stepping motor 2 drives the turntable 1 to rotate through the speed reducer, that is, the rotating shaft of the stepping motor 2 is connected to the speed reducer, and the rotating center of the turntable 1 is arranged on the output shaft of the speed reducer; in other possible embodiments, the turntable 1 is supported on a plane through a bearing 4, and the rotating shaft of the stepping motor 2 and the rotating center of the turntable 1 are respectively provided with a driving wheel, and the driving wheel drives the turntable 1 to rotate through a belt or a synchronous belt.

Referring to fig. 5-7, the electric turntable control system includes a first proximity switch 6, a second proximity switch 7, a main control IC1, and a stepping motor control chip U1 for controlling the operation of the stepping motor 2; the first proximity switch 6, the second proximity switch 7 and the stepping motor control chip U1 are all in signal connection with the main control IC 1.

The first proximity switch 6 and the second proximity switch 7 are both photoelectric proximity switches, and when an object approaches in front of the induction heads of the first proximity switch 6 and the second proximity switch 7, the first proximity switch 6 and the second proximity switch 7 can be triggered; in this embodiment, after the first proximity switch 6 and the second proximity switch 7 are triggered, a pulse is sent out from the signal output terminal.

Sensing positions are circumferentially arranged on the rotary table 1 at intervals, the sensing positions comprise triggering positions 91 and non-triggering positions 92, and the intervals of the triggering positions 91 and the non-triggering positions 92 are equal and are alternately arranged; the first proximity switch 6 and the second proximity switch 7 are sequentially arranged along the clockwise rotation direction of the rotary table 1, and the first proximity switch 6 and the second proximity switch 7 are separated by a sensing position; in the embodiment, an induction ring 8 is fixed below the rotary table 1, the induction ring 8 is fixed below the rotary table 1 through a screw, the induction ring 8 is coaxial with the rotary table 1, the induction ring 8 is fixed with the transmission ring 3, so that the rotary table 1 and the transmission ring 3 are fixed, and when the stepping motor 2 drives the transmission ring 3 to rotate, the induction ring 8 and the rotary table 1 also rotate coaxially with the transmission ring 3; the induction ring 8 is axially provided with a convex rib 81 and a concave groove 82, the convex rib 81 and the concave groove 82 are equal in width and are alternately arranged, the first proximity switch 6 and the second proximity switch 7 are arranged along the clockwise rotation direction of the rotary table 1, the convex rib 81 can trigger the first proximity switch 6 and the second proximity switch 7, namely corresponding to a trigger position 91, the concave groove 82 cannot trigger the first proximity switch 6 and the second proximity switch 7, namely corresponding to a non-trigger position 92, and the first proximity switch 6 and the second proximity switch 7 are separated by the width distance of the convex rib 81 or the concave groove 82, namely the first proximity switch 6 and the second proximity switch 7 are separated by a sensing position; in this embodiment, the first proximity switch 6 and the second proximity switch 7 are fixed on the plane of the support bearing 4 by brackets.

The main control IC1 is a Micro Controller Unit (MCU), in this embodiment, the main control IC1 is a single chip microcomputer of 15W408 type, pins 1 to 5, pin 7, and pins 9 to 16 are all general input/output pins, pin 6 is a VCC pin, pin 8 is a GND pin, the main control IC1 is mounted on a Printed Circuit Board (PCB), and a connector is disposed on the Printed Circuit Board by welding for the main control IC1 to be in signal connection with the first proximity switch 6, the second proximity switch 7, and the stepper motor control chip U1, respectively.

The model of the stepping motor control chip U1 is TMC2208 QFN28, the stepping motor control chip U1 is mounted on another Printed Circuit Board (PCB), a connector is arranged on the PCB by welding for the stepping motor control chip U1 to be in signal connection with the main control IC1 and to be electrically connected with the stepping motor 2, and part of the pins of the stepping motor control chip U1 are defined as:

pin 1: OB2, port 2 output port of winding B of the stepping motor;

and a pin 2: ENN, enabling a port by the stepping motor, and setting the stepping motor to float when the port is at a high level;

pin 16: STEP, STEP signal input port;

pin 19: DIR, direction signal input port;

pin 21: OA2, port 2 output port of winding a of the stepper motor;

pin 24: OA1, port 1 output port of winding A of the stepping motor;

pin 26: OB1, port 1 output port of winding B of the stepper motor.

The first proximity switch 6 and the second proximity switch 7 are both in signal connection with a general-purpose input/output pin of the main control IC1, and specifically, signal output terminals of the first proximity switch 6 and the second proximity switch 7 are connected to a connector of a printed circuit board on which the main control IC1 is mounted, and are connected to the pin 2 and the pin 1 of the main control IC1 through printed circuits on the printed circuit board, so that the pin 2 and the pin 1 of the main control IC1 can receive pulses of the first proximity switch 6 and the second proximity switch 7, respectively.

The ENN pin, STEP pin, and DIR pin of the stepper motor control chip U1 are all signal connected to the general input/output pin of the main control IC1, and specifically, the connector of the printed circuit board on which the main control IC1 is mounted and the connector of the printed circuit board on which the stepper motor control chip U1 is mounted are connected by wires or cables, and pin 2(ENN pin) of the stepper motor control chip U1 is signal connected to pin 13 of the main control IC1 by printed circuits on the two printed circuit boards, pin 16(STEP pin) of the stepper motor control chip U1 is signal connected to pin 7 of the main control IC1, and pin 19(DIR pin) of the stepper motor control chip U1 is signal connected to pin 5 of the main control IC 1.

The OA1 pin of the stepping motor control chip U1 is connected to port 1 of winding a of the stepping motor 2, the OA2 pin of the stepping motor control chip U1 is connected to port 2 of winding a of the stepping motor 2, the OB1 pin of the stepping motor control chip U1 is connected to port 1 of winding B of the stepping motor 2, the OB2 pin of the stepping motor control chip U1 is connected to port 2 of winding B of the stepping motor 2, specifically, the above four winding ports of the stepping motor 2, connected to a connector P1 of a printed circuit board on which a stepping motor control chip U1 is mounted by a wire, and through the printed circuit on the printed circuit board, the pin 1, the pin 21, the pin 24 and the pin 26 of the stepping motor control chip U1 are respectively and correspondingly connected with the four winding ports of the stepping motor 2, so that the stepping motor control chip U1 can drive and control the operation of the stepping motor 2.

Referring to fig. 8, further, the electric turntable control system further includes a power supply module for supplying power to the main control IC1 and the stepping motor control chip U1; in this embodiment, the power supply module includes a voltage stabilization chip IC2, the model of the voltage stabilization chip IC2 is HT7550, a dc 12V voltage port is connected to a Vin pin of the voltage stabilization chip IC2 after passing through a diode D1, a resistor R7, and a capacitor C15, a capacitor C18, and a capacitor C9 which are connected in series, and a Vout pin of the voltage stabilization chip IC2 is connected to a VCC network to provide a voltage-stabilized 5V dc power supply, thereby supplying power to the main control IC1 and the stepping motor control chip U1; the power supply module and the master control IC1 are mounted on the same printed circuit board, the power supply module supplies power to the master control IC1 through the printed circuit board, and the power supply module supplies power to the stepping motor control chip U1 after being connected with the printed circuit board mounted with the stepping motor control chip U1 through a connector and a lead.

Referring to fig. 9 and 10, the present invention further provides a method for controlling an electric turntable, in which the above-mentioned electric turntable control system is applied, and the method comprises the following steps:

s1, the main control IC1 detects whether the first proximity switch 6 and the second proximity switch 7 send out trigger signals simultaneously; if yes, go to step S2; if not, the stepping motor 2 is turned off.

If the rotary table 1 is rotating, the rotary table will inevitably rotate to the position of triggering the first proximity switch 6 and the second proximity switch 7 at the same time, and at this time, the first proximity switch 6 and the second proximity switch 7 simultaneously send out pulses to the main control IC 1; if the turntable 1 is pressed by a human hand and cannot rotate, the first proximity switch 6 and the second proximity switch 7 cannot be triggered simultaneously, at this time, the pin 13 of the main control IC1 keeps high-level output, namely, the pin ENN of the stepping motor control chip U1 keeps high level, and the stepping motor 2 is set to float, namely, stopped; even if the turntable 1 reaches a position for triggering the first proximity switch 6 and the second proximity switch 7 at the same time, only one pulse can be sent out by the first proximity switch 6 and the second proximity switch 7 at the same time, the next pulse of the first proximity switch 6 and the second proximity switch 7 is not detected by the main control IC1 within a period of time, at this time, the pin 13 of the main control IC1 is also kept at a high level output, namely, the pin ENN of the stepper motor control chip U1 is kept at a high level, and the stepper motor 2 is set to float, namely, is stopped.

With this step, it is possible to realize: when the turn table 1 is rotated and pressed by a hand of a person, the stepping motor 2 is turned off, and the rotation operation of the turn table 1 is stopped.

S2, the main control IC1 detects signals sent by the first proximity switch 6 and the second proximity switch 7; if the first proximity switch 6 sends a trigger signal and the second proximity switch 7 sends a non-trigger signal, the stepping motor 2 is controlled to drive the rotary table 1 to rotate anticlockwise; if the second proximity switch 7 sends a trigger signal and the first proximity switch 6 sends a non-trigger signal, the stepping motor 2 is controlled to drive the rotary table 1 to rotate clockwise.

If the first proximity switch 6 and the second proximity switch 7 are triggered and send out pulse signals at the same time, then the first proximity switch 6 is triggered again and sends out pulse signals, and the second proximity switch 7 is not triggered and keeps silent, it indicates that the turntable 1 is rotating counterclockwise, at this time, the pin 19 of the main control IC1 keeps a level, so that the DIR pin of the stepper motor control chip U1 keeps the level, the stepper motor 2 is operated in a direction to drive the turntable 1 to rotate counterclockwise, and the pin 16 of the main control IC1 keeps sending pulses, so that the STEP pin of the stepper motor control chip U1 keeps receiving pulse signals, thereby keeping the stepper motor 2 operating.

If the first proximity switch 6 and the second proximity switch 7 are triggered and pulse signals are sent at the same time, then the first proximity switch 6 is not triggered and remains silent, the second proximity switch 7 is triggered again and sends pulse signals, indicating that the turntable 1 is rotating clockwise, at this time, the pin 19 of the main control IC1 maintains another level, so that the DIR pin of the stepper motor control chip U1 maintains the level, the stepper motor 2 is operated in a direction driving the turntable 1 to rotate clockwise, and the pin 16 of the main control IC1 continues to pulse, so that the STEP pin of the stepper motor control chip U1 continues to receive pulse signals, thereby keeping the stepper motor 2 operating.

With this step, it is possible to realize:

1. when the rotary table 1 is static, if the rotary table is pushed by a human hand, the rotary table 1 rotates towards the direction pushed by the human hand;

2. when the rotary table 1 rotates, if the rotary table is pushed reversely by a human hand, the rotary table 1 is changed to rotate towards the pushing direction of the human hand.

S3, the step S1 is executed continuously.

Continuing to execute the step S1, the main control IC1 continuously detects whether the first proximity switch 6 and the second proximity switch 7 simultaneously send out trigger signals, so as to realize the continuous operation or stop of the turntable 1 according to the steps S1 and S2.

Further, after step S2, the method further includes:

when the stepping motor 2 drives the rotary table 1 to rotate anticlockwise, if the first proximity switch 6 accelerates to send a trigger signal and the second proximity switch 7 accelerates to send a non-trigger signal, the stepping motor 2 is controlled to rotate anticlockwise in an accelerated manner.

When the stepping motor 2 drives the turntable 1 to rotate anticlockwise, the master control IC1 records a time interval that the first proximity switch 6 sends out a pulse signal and the second proximity switch 7 keeps silent twice, if a time interval that the subsequent first proximity switch 6 sends out a pulse signal and the second proximity switch 7 keeps silent is shortened to be one half or less of a previous time interval, it indicates that the turntable 1 is being accelerated and pushed by a human hand, at this time, the pin 16 of the master control IC1 accelerates to send out a pulse, so that the STEP pin of the stepping motor control chip U1 accelerates to receive a pulse signal, thereby driving the stepping motor 2 to rotate in an accelerated manner, and further accelerating the turntable 1 to rotate.

When the stepping motor 2 drives the rotary table 1 to rotate clockwise, if the second proximity switch 7 accelerates to send a trigger signal and the first proximity switch 6 accelerates to send a non-trigger signal, the stepping motor 2 is controlled to rotate clockwise in an accelerated manner.

When the stepping motor 2 drives the turntable 1 to rotate clockwise, the master control IC1 records the time interval that the second proximity switch 7 sends out the pulse signal and the first proximity switch 6 keeps silent twice, if the time interval that the subsequent second proximity switch 7 sends out the pulse signal and the first proximity switch 6 keeps silent is shortened to one half or less of the previous time interval, it indicates that the turntable 1 is being accelerated and pushed by a human hand, at this moment, the pin 16 of the master control IC1 accelerates to send out the pulse, so that the STEP pin of the stepping motor control chip U1 accelerates to receive the pulse signal, thereby driving the stepping motor 2 to rotate acceleratively, and further enabling the turntable 1 to rotate acceleratively.

Further, after the operation state of the stepping motor 2 is changed each time, the changed operation state of the stepping motor 2 is stored in the memory of the main control IC 1; when the main control IC1 is started, the stepping motor 2 is driven to operate in the operating state stored in the memory; meanwhile, the main control IC1 can acquire the current running state of the stepping motor 2; in this embodiment, the memory is an EPROM built in the main control IC1, and the operation state is the operation direction and the rotation speed of the stepping motor 2.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.