CN110424093B

CN110424093B - Brushless controller for controlling roller operation of computerized flat knitting machine

Info

Publication number: CN110424093B
Application number: CN201910719266.4A
Authority: CN
Inventors: 吴泽明; 许海平; 刘建华; 章传喜
Original assignee: CHANGZHOU ZEMING AUTO EQUIPMENT CO LTD
Current assignee: CHANGZHOU ZEMING AUTO EQUIPMENT CO LTD
Priority date: 2019-08-05
Filing date: 2019-08-05
Publication date: 2021-02-12
Anticipated expiration: 2039-08-05
Also published as: CN110424093A

Abstract

The invention discloses a brushless controller for controlling roller operation of a computerized flat knitting machine, which comprises: the input end of the optical coupling circuit is connected with the pulse signal output end of the roller control module and used for converting the pulse signal into a frequency signal; the first input end of the master control circuit is connected with the output end of the optical coupling circuit and is used for acquiring frequency signals; a sampling circuit; the input end of the sampling circuit is connected with the first output end of the main control circuit and is used for sampling the frequency signal; the input end of the filter circuit is connected with the output end of the sampling circuit and used for filtering the frequency signal and converting the frequency signal into a timing signal; the input end of the power tube pushing circuit is connected with the output end of the filter circuit and used for adjusting the output duty ratio signal according to the timing signal; the output end of the power tube pushing circuit is connected with the second input end of the main control circuit, and the main control circuit drives the brushless motor according to the duty ratio signal, so that the brushless motor replaces the stepping motor to drive the computerized flat knitting machine to control the roller to operate.

Description

Brushless controller for controlling roller operation of computerized flat knitting machine

Technical Field

The invention relates to the technical field of controllers, in particular to a brushless controller for controlling roller operation of a computerized flat knitting machine.

Background

The operation modes of the control rollers on the existing nationwide computerized flat knitting machines are as follows: a90 BYG type stepping motor is matched with a reduction gearbox (generally about 1: 20) with a large reduction ratio to be connected with the roller, and a stepping motor driver drives the 90BYG type stepping motor to run through a pulse signal (pulse frequency is adjustable) sent by a receiving system, so that the winding time, speed, angle and tension of the fabric on the roller are controlled in real time.

The existing scheme of using the stepping motor has the following defects:

first, the torque is insufficient. The operating speed requirement of the machine is faster and faster, the efficiency requirement is higher and higher, the operating characteristics of the stepping motor are that the torque is more and more reduced along with the increase of the speed, the cost is increased by increasing the power of the motor, the rotational inertia of the motor is increased, the inertia is increased, the opening and closing real-time performance of a needle plate which must rapidly react within dozens of milliseconds cannot meet the requirement, once a firing pin occurs, hundreds or even thousands of needles are damaged, and the real-time performance of rapid reaction is challenged; the problem that the running speed of the stepping motor cannot be greatly improved is caused by increasing the reduction ratio of the reduction gearbox. This is in principle conflicting.

Second, the speed is insufficient. The working efficiency of the machine is improved, the running speed of the roller is improved, and the working characteristics of the stepping motor are mainly used for positioning, but the running speed of the belt load is generally not high, and the speed is the bottleneck.

Thirdly, the energy consumption is high. The stepping motor is a position control motor, the precision requirements on the position and the angle are concerned, and 60-70% of energy consumption is wasted.

Disclosure of Invention

In view of this, the embodiment of the present invention provides a brushless controller for controlling operation of a roller of a computerized flat knitting machine, so as to solve the problems of insufficient torsion, insufficient speed and high energy consumption of the roller of the flat knitting machine driven by a stepping motor in the prior art.

The embodiment of the invention provides a brushless controller for controlling roller operation of a computerized flat knitting machine, which comprises:

the input end of the optical coupling circuit is connected with the pulse signal output end of the roller control module and used for converting the pulse signal into a frequency signal;

the first input end of the master control circuit is connected with the output end of the optical coupling circuit and is used for acquiring frequency signals;

the input end of the sampling circuit is connected with the first output end of the main control circuit and is used for sampling the frequency signal;

the input end of the filter circuit is connected with the output end of the sampling circuit and used for filtering the frequency signal and converting the frequency signal into a timing signal;

the input end of the power tube pushing circuit is connected with the output end of the filter circuit and used for adjusting the output duty ratio signal according to the timing signal; the output end of the power tube pushing circuit is connected with the second input end of the main control circuit, and the main control circuit drives the brushless motor according to the duty ratio signal.

Optionally, the method further comprises: the input end of the bus current sampling circuit is connected with the bus circuit, and the output end of the bus current sampling circuit is connected with the third input end of the main control circuit and used for detecting a current signal of the bus circuit and sending the current signal to the main control circuit; when the bus circuit has an overcurrent phenomenon, the main control circuit is interrupted.

Optionally, the bus current sampling circuit is further configured to collect a locking current of the bus circuit;

and the main control circuit adjusts the locking torque according to the locking current.

Optionally, the method further comprises: the bus voltage sampling circuit is connected with the third output end of the main control circuit and is used for detecting a voltage signal of the main control circuit; when the main control circuit generates an overvoltage phenomenon, the bus voltage sampling circuit is interrupted.

Optionally, the relationship between the frequency signal and the duty ratio signal is a positive correlation.

Optionally, the method further comprises: and the input end of the Hall-free detection circuit is connected with the fourth output end of the main control circuit.

Optionally, the method further comprises: and the input end of the Hall detection circuit is connected with the fifth output end of the main control circuit and is used for determining the position of the motor rotor.

Optionally, the method further comprises: and the output end of the program programming port circuit is connected with the fourth input end of the main control circuit.

Optionally: and the power supply control module is connected with the main control circuit, the sampling circuit, the filter circuit and the power tube pushing circuit.

Optionally: the brushless motor is characterized by also comprising an angular displacement sensor, wherein the angular displacement sensor is arranged on the brushless motor, and the output end of the angular displacement sensor is connected with the main control circuit;

after the brushless motor is locked through the locking torque, detecting whether the brushless motor rotates or not through the angular displacement sensor, and cutting off the locking current if the brushless motor continues to rotate;

and detecting the range of each rotation angle of the brushless motor in real time through the angular displacement sensor, and if the range of the single rotation angle of the brushless motor exceeds a set value, stopping the driving current of the brushless motor.

The embodiment of the invention has the following beneficial effects:

1. the main control chip receives the frequency signal, samples and filters the frequency signal to obtain a timing signal, and the timing signal changes the output duty ratios of pins P8, P9, P10, P11, P14 and P15 of the main control chip, so that the power tube is pushed to change the driving duty ratio and the phase sequence of the brushless motor. The main control chip processes the pulse signal by receiving the pulse signal of the roller control module, converts the pulse signal into a duty ratio output to control the running state of the brushless motor, and therefore the brushless motor replaces a stepping motor to drive the computerized flat knitting machine to control the roller to run.

2. The main control chip collects locking current through bus current sampling, and controls torque through controlling a motor driving duty ratio, so that the locking current corresponds to the torque.

3. After the pulse signal is converted into the frequency signal, the corresponding output duty ratio is calculated according to actual needs, and the application of the brushless motor to replace a stepping motor in the driving of the control roller of the computerized flat knitting machine is realized.

Drawings

The features and advantages of the present invention will be more clearly understood by reference to the accompanying drawings, which are illustrative and not to be construed as limiting the invention in any way, and in which:

FIG. 1 is a diagram illustrating a structure of a brushless controller for controlling roller operation of a computerized flat knitting machine according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of an optical coupler circuit according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of a main control chip according to an embodiment of the present invention;

FIG. 4 is a diagram illustrating a power tube driving circuit according to an embodiment of the present invention;

FIG. 5 is a block diagram of a bus current sampling circuit according to an embodiment of the present invention;

FIG. 6 is a block diagram of a bus voltage sampling circuit according to an embodiment of the present invention;

FIG. 7 is a diagram illustrating a Hall-free detection circuit according to an embodiment of the present invention;

FIG. 8 is a diagram showing a structure of a Hall detection circuit according to an embodiment of the present invention;

FIG. 9 is a circuit diagram of a program programming port according to an embodiment of the present invention;

FIG. 10 is a diagram illustrating a power control module in accordance with an embodiment of the present invention;

fig. 11 shows a structure of an LED lamp display circuit according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, 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 some, but not all, embodiments of the present invention. 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.

Example one

The speed regulation of the present brushless motor is basically applied in the technical level by the following two types: analog voltage speed regulation and PWM speed regulation (namely duty ratio speed regulation), and pulse frequency speed regulation is adopted in the embodiment of the invention.

The embodiment of the invention provides a brushless controller for controlling roller operation of a computerized flat knitting machine, which comprises an optical coupling circuit 1, a main control circuit 2, a sampling circuit 3, a filter circuit 4 and a power tube pushing circuit 5, as shown in figure 1, wherein: the input end of the optical coupling circuit 1 is connected with the pulse signal output end of the roller control module and used for converting the pulse signal into a frequency signal; the first input end of the main control circuit 2 is connected with the output end of the optical coupling circuit 1 and is used for collecting frequency signals; the input end of the sampling circuit 3 is connected with the first output end of the main control circuit 2 and is used for sampling the frequency signal; the input end of the filter circuit 4 is connected with the output end of the sampling circuit 3 and is used for filtering the frequency signal and converting the frequency signal into a timing signal; the input end of the power tube pushing circuit 5 is connected with the output end of the filter circuit 4 and used for outputting a duty ratio signal according to the timing signal; the duty cycle signal is used to drive the brushless motor.

In this embodiment, the functions of the main control circuit, the sampling circuit and the filter circuit are all realized by the main control chip, and the optical coupling circuit and the power tube driving circuit are peripheral circuits. As shown in fig. 2-4, the main control chip is a dsPIC33 series chip, a P35 pin of the main control chip is connected with an output end of an optocoupler UU1, a P21 pin of the main control chip is connected with an output end of the optocoupler UU2, input ends of the optocouplers UU1 and UU2 are connected with a roller control module of the flat knitting machine, and a pulse signal output by the roller control module is converted into a frequency signal. The main control chip receives the frequency signal, samples and filters the frequency signal to obtain a timing signal, and the timing signal changes the output duty ratios of pins P8, P9, P10, P11, P14 and P15 of the main control chip, so that the power tube is pushed to change the driving duty ratio and the phase sequence of the brushless motor.

In the specific embodiment, the brushless motor parameters are 150W, DC48V, no load is 1800 turns, and the reduction box (1:50) replaces the original 90BYG stepper motor with 2H20504, 8 subdivision, and two speeds of 1.6KHz to 3.2 Khz. The amplitude of the pulse signal and the direction signal driven by the roller is +12V, the pulse range is 1-10KHz, and the system parameter corresponding to the whole flat knitting machine is 1-100. The main control chip has the following functions: and receiving a pulse signal of the roller control module, processing the pulse signal, converting the processed pulse signal into a duty ratio, and outputting the duty ratio to control the running state of the brushless motor, so that the brushless motor replaces a stepping motor to drive the computerized flat knitting machine to control the roller to run.

As an alternative embodiment, as shown in fig. 5, the method further includes: the input end of the bus current sampling circuit is connected with the bus circuit, and the output end of the bus current sampling circuit is connected with the second input end of the main control circuit and used for detecting a current signal of the bus circuit and sending the current signal to the main control circuit; when the bus circuit has an overcurrent phenomenon, the main control circuit is interrupted.

In this embodiment, the P20 pin of the main control chip receives the sampling result of the bus current sampling circuit and monitors the sampling result.

As an optional implementation manner, the bus current sampling circuit is further configured to collect a locking current of the bus circuit; and the main control circuit adjusts the locking torque according to the locking current.

In this embodiment, the main control chip collects the locking current through bus current sampling, and controls the torque by controlling the motor driving duty ratio, so as to realize the correspondence between the locking current and the torque. The correspondence relationship between the motor lock-up current and the torque is shown in table 1. The brushless motor is locked after stalling, and the locking torque is adjusted according to the locking current, so that the roller is prevented from continuously rolling after the brushless motor stalls, a needle plate is prevented from being opened, and the condition of firing pin is avoided.

Motor locking current (A)	Lock-up torque (Nm)
		0.1	1
0.2	2
		0.3	3
0.4	4
		0.5	5
0.6	6
		0.7	7
0.8	8
		0.9	9
1	10

TABLE 1

As an alternative embodiment, as shown in fig. 6, the method further includes: the input end of the bus voltage sampling circuit is connected with the third output end of the main control circuit and is used for detecting a voltage signal of the main control circuit; when the main control circuit generates an overvoltage phenomenon, the bus voltage sampling circuit is interrupted.

In this embodiment, the P19 pin of the main control chip receives the sampling result of the bus voltage sampling circuit and monitors the sampling result.

As an alternative embodiment, the relationship between the frequency signal and the duty ratio signal is a positive correlation.

In the present embodiment, the relationship between the frequency signal and the duty ratio signal is shown in table 2. After the pulse signals are converted into frequency signals, corresponding output duty ratios are calculated according to actual requirements, and the application of the brushless motor in replacing the brushless motor in driving of the control roller of the computerized flat knitting machine is realized.

TABLE 2

As an alternative embodiment, as shown in fig. 7, the method further includes: the input end of the Hall-free detection circuit is connected with the fourth output end of the main control circuit.

In the embodiment, the P22-24 pin of the main control chip is connected with a Hall detection circuit, the position of the motor rotor is determined through back electromotive force detection, and the motor can be operated without a Hall position sensor.

As an alternative embodiment, as shown in fig. 8, the method further includes: the input end of the Hall detection circuit is connected with the fifth output end of the main control circuit and used for determining the position of the motor rotor.

In this embodiment, the pins (HA, HB, HC) of the P25-27 chip of the main control chip are connected to the HALL signal lines of the dc brushless motor, the HALL signal of the motor is filtered by the rc element to form an HALL _ A, HALL _ B, HALL _ C signal, and the HALL position of the motor is obtained by the main control chip sampling the HALL _ A, HALL _ B, HALL _ C high and low levels, so as to output a correct phase change signal of the motor and control the normal operation of the motor.

As an alternative embodiment, as shown in fig. 9, the method further includes: and the output end of the program programming port circuit is connected with the third input end of the main control circuit.

In the present embodiment, the pins P34, P37, P41 and P42 of the main control chip are connected to the output terminal of the program programming port circuit for writing the control program, such as the relationship between the frequency signal and the duty ratio signal, and the corresponding relationship between the locking current and the torque in the foregoing embodiments.

As an alternative embodiment, as shown in fig. 10, the method further includes: and the power supply control module is connected with the main control circuit, the sampling circuit, the filter circuit and the power tube pushing circuit.

In the embodiment, the power input ends are connecting terminals J1_1 (connected with the positive pole of the power supply) and J1_2 (connected with the negative pole of the power supply), and the power voltage range is 24V-48V. The direct current power supply control module provides 3.3V, 5V and 15V direct current voltage sources for each chip circuit. J1_3, J1_4 and J1_5(U, V, W) are connected with the DC brushless motor wire.

In a specific embodiment, as shown in fig. 11, the LED lamp is further included, and is connected to a P2 pin of the main control chip, and the LED lamp is turned on in case of a fault and turned off in case of a normal fault.

Example two

In order to detect the rotation of the brushless motor, in this embodiment, the brushless motor further includes an angular displacement sensor, which is disposed on the brushless motor and used for detecting the rotation process of the brushless motor, and an output end of the angular displacement sensor is connected to the main control circuit and feeds back the rotor angular position information to the main control circuit.

Particularly, in the invention, the locking torque is provided for locking the brushless motor after the brushless motor operates at a specific angle each time, the fabric on the roller is tightened, meanwhile, the tightening force cannot be too large to avoid the fabric from being broken or deformed, and if the locking torque is not provided, the roller can continue to rotate and lose position under the tightening force of the fabric, so that the next knitting process is influenced.

However, in an extreme case, for example, the fabric is not tensioned or broken, so that there is no pre-tightening force on the roller, and at this time, if the brushless motor continues to provide the locking torque after a single operation is finished, the brushless motor is driven to continue to operate, so that a fault such as further dislocation is caused, and therefore it is necessary to detect whether the brushless motor continues to rotate after providing the locking torque. Specifically, after the brushless motor is locked through the locking torque, whether the brushless motor rotates is detected through the angular displacement sensor, if the brushless motor continues to rotate, the locking current is cut off, the situation that the brushless motor continues to operate to cause faults is avoided, and a protection effect is achieved.

And on the other hand, the roller is specific in each rotation angle range, the angular displacement sensor is used for detecting the rotation angle range of the brushless motor in real time, and if the single rotation angle range of the brushless motor exceeds a set value, the driving current of the brushless motor is stopped. When the single operation angle of the brushless motor exceeds the range, the equipment is in a fault or step-out state, if the fault is not found in time, the knitting head can be interrupted, and the loss is overlarge.

Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations fall within the scope defined by the appended claims.

Claims

1. The utility model provides a brushless controller of computerized flat knitting machine control roller operation which characterized in that includes:

the first input end of the master control circuit is connected with the output end of the optical coupling circuit and is used for acquiring the frequency signal;

the input end of the filter circuit is connected with the output end of the sampling circuit and is used for filtering the frequency signal and converting the frequency signal into a timing signal;

the input end of the power tube pushing circuit is connected with the output end of the filter circuit and used for adjusting the output duty ratio signal according to the timing signal; the output end of the power tube pushing circuit is connected with the second input end of the main control circuit, and the main control circuit drives the brushless motor according to the duty ratio signal;

the input end of the bus current sampling circuit is connected with the bus circuit, and the output end of the bus current sampling circuit is connected with the third input end of the main control circuit and used for detecting a current signal of the bus circuit and sending the current signal to the main control circuit; when the bus circuit has an overcurrent phenomenon, the main control circuit is interrupted; the bus current sampling circuit is also used for collecting the locking current of the bus circuit; and the main control circuit adjusts the locking torque according to the locking current.

2. The brushless controller of claim 1, further comprising: the bus voltage sampling circuit is connected with the third output end of the main control circuit and is used for detecting a voltage signal of the main control circuit; when the main control circuit generates an overvoltage phenomenon, the bus voltage sampling circuit is interrupted.

3. The brushless controller of claim 1, wherein the frequency signal is positively correlated with the duty cycle signal.

4. The brushless controller of claim 1, further comprising: and the input end of the Hall-free detection circuit is connected with the fourth output end of the main control circuit.

5. The brushless controller of claim 1, further comprising: and the input end of the Hall detection circuit is connected with the fifth output end of the main control circuit and is used for determining the position of the motor rotor.

6. The brushless controller of claim 1, further comprising: and the output end of the program programming port circuit is connected with the fourth input end of the main control circuit.

7. The brushless controller of claim 1, further comprising: and the power supply control module is connected with the main control circuit, the sampling circuit, the filter circuit and the power tube pushing circuit.

8. The brushless controller of claim 1, further comprising an angular displacement sensor disposed on the brushless motor, an output of the angular displacement sensor being connected to the main control circuit;