CN100579791C - drive control device - Google Patents

Abstract

A drive control device is applied to a printing head and a drive transmission device on a printing device, and comprises: a path planning unit which can output a position command value and a speed command value; the feedback unit is in signal connection with the printing head and generates a position feedback signal and a speed feedback signal according to the position and the speed of the printing head; the proportional-integral controller is in signal connection with the path planning unit, the feedback unit and the driving transmission device, generates a first control signal according to a difference value of the position command value and the position feedback signal and a difference value of the speed command value and the speed feedback signal, and sends the first control signal to the driving transmission device; and the feedforward controller is in signal connection with the path planning unit and the driving transmission device, receives the speed command value for operation to generate a second control signal and sends the second control signal to the driving transmission device, so that the driving transmission device can drive the printing head to move according to the first control signal and the second control signal.

Description

drive control device

technical field

The invention relates to a drive control device, in particular to a drive control device applied to a printing head and a drive transmission device of a printing device.

Background technique

Please refer to FIG. 1 , which is a schematic diagram of the internal structure of a common inkjet printer, wherein the motor 12 drives the gear 13 and the belt 14 to move, so that the bearing seat 11 of the inkjet head 10 can perform linear reciprocating motion along the sliding rod 19, So that the inkjet head 10 can go to a predetermined position to perform printing tasks. In order to enable the control unit (not shown in this figure) to know the exact position of the inkjet head 10, an optical encoder 15 also carried on the bearing seat 11 will generate a position feedback signal according to the scale on the optical scale 16. The speed feedback signal is transmitted to the control unit to control the movement of the inkjet head 10 .

Referring to Fig. 2 again, it is the internal functional block schematic diagram of the common control unit of above-mentioned ink-jet printer, wherein proportional-integral-differential controller (PID controller) 21 is according to the position command value that path planning unit (pathplanning unit) 20 outputs and The speed command value is calculated to generate a control signal (usually a pulse width modulation signal) output to the driving device 22 (usually including the above-mentioned motor 12), and then control the driving device 22 to drive the above-mentioned gear 13, belt 14 and inkjet A mechanical device (plant) 23 composed of the head 10 and the like. The position feedback signal and speed feedback signal generated by the feedback unit 24 formed by the above-mentioned optical encoder 15 and optical ruler 16 are fed back to the input end of the proportional-integral-derivative controller 21 to be compared with the position command value and the speed command value. After the subtraction, the position error signal and the speed error signal are obtained and then input to the proportional-integral-derivative controller 21, so that the proportional-integral-derivative controller 21 generates the control signal according to the magnitude of the position error signal and the speed error signal to control The driving force of the driving device 22.

However, in the above-mentioned common technical means, the error signal is mainly input into the proportional-integral-derivative controller 21 for calculation, so the error value must be large enough to generate a sufficiently large voltage signal to drive the driving device 22, so the common technical means will have The disadvantages of slow response speed and large speed control error. Therefore, there is a need to improve the above mentioned deficiencies in the device structure.

Contents of the invention

The object of the present invention is to provide a drive control device to solve the shortcomings of slow response speed and large speed control error in the prior art. To achieve the above object, the present invention provides a drive control device, which is applied to a print head and a drive transmission device on a printing device, the drive control device includes: a path planning unit, which can output a position command value and a speed command value; The feedback unit is connected with the printing head signal, which generates a position feedback signal and a speed feedback signal according to the position and speed of the printing head; a proportional-integral controller is connected with the path planning unit, the feedback unit and the driving transmission device signal connected to generate a first control signal based on the difference between the position command value and the position feedback signal and the difference between the speed command value and the speed feedback signal and send the first control signal to the drive transmission; and A feed-forward controller is connected to the path planning unit and the driving transmission device, receives the speed command value and performs calculation to generate a second control signal and sends the second control signal to the driving transmission device, so that the The driving transmission device can simultaneously drive the printing head to move according to the first control signal and the second control signal.

According to the technical concept above, in the drive control device of the present invention, the feedback unit is connected to the optical encoder and the optical scale in the print head for signals, and the optical encoder and the optical scale can reflect the position and position of the print head. speed.

According to the technical concept above, in the drive control device of the present invention, the first control signal generated by the proportional-integral controller is kp×(speed command value-speed feedback signal)+ki×(position command value-position Feedback signal), where kp and ki are the gain values of the proportional-integral controller.

According to the technical concept above, in the drive control device of the present invention, the second control signal generated by the feedforward controller is c1×speed command value+c2, where c1 and c2 are constants and can be passed to the drive transmission The device is determined by system identification.

According to the above technical concept, in the drive control device of the present invention, the drive transmission device includes a DC motor and a transmission mechanism.

According to the technical concept above, in the drive control device of the present invention, the transmission mechanism includes a gear set and a transmission belt.

According to the above technical concept, the drive control device of the present invention, wherein the printing head is an inkjet head.

The beneficial effects and advantages of the present invention include that the added feed-forward controller of the present invention generates the control voltage directly according to the speed command value output by the path planning unit, so it can directly compensate the counter electromotive force required by the DC motor under constant speed Voltage and the voltage required to overcome the dynamic friction between the gear set and the transmission belt, so the position error and speed error generated by the feedback signal can be effectively reduced, so there is no need to change the gain value of the proportional-integral controller kp and ki is designed to be a very large value, thereby increasing the stability of the system and reducing the speed error of constant speed control. In this way, the reaction speed of the system can be accelerated, and the stability of the system can be increased at the same time, and the speed error of the inkjet head under constant speed control can be effectively reduced.

Description of drawings

Through the following drawings and descriptions, the present invention can be further understood:

FIG. 1 is a schematic diagram of the internal structure of a common inkjet printer.

FIG. 2 is a schematic diagram of internal functional blocks of a common control unit of an inkjet printer.

FIG. 3 is a functional block diagram of a preferred embodiment of the inkjet head drive control device of the present invention.

Wherein, the reference signs are explained as follows:

inkjet head 10 bearing seat 11 motor 12

Driving gear 13 Belt 14 Optical encoder 15

Optical ruler 16 sliding rod 19 path planning unit 20

Proportional-integral-derivative controller21 Drive device22 Mechanical equipment23

Feedback unit 24 Path planning unit 30 Feedback unit 31

Proportional-integral controller 32 Feedforward controller 33 Drive transmission 38

Motor drive integrated circuit 380 DC motor 381 Transmission mechanism 382

Gear set 3820 Drive belt 3821 Print head 39

Detailed ways

Please refer to Fig. 3, which is a functional block diagram of a preferred embodiment of an inkjet head drive control device that can improve the defects of the present invention and can be applied to an inkjet printer or an inkjet multifunction machine, which mainly includes Path planning unit 30, feedback unit 31, proportional-integral controller 32 and feedforward controller 33, wherein path planning unit 30 is the same as the prior art, it is used to output position command value P and speed command value V, and feedback unit 31 mainly generates the position feedback signal Pf and the speed feedback signal Vf according to the actual position and speed of the print head 39, and the proportional-integral controller 32 generates the position feedback signal Pf and the speed feedback signal Vf according to the difference Pd between the position command value P and the position feedback signal Pf and the speed The difference Vd between the command value V and the speed feedback signal Vf generates the first control signal S1. The feed-forward controller 33 directly receives the speed command value V for calculation to generate the second control signal S2. The first control signal S1 and the second control signal S2 are transmitted to the driving transmission device 38, so that the driving transmission device 38 can simultaneously drive the printing head according to the first control signal S1 and the second control signal S2. move.

The second control signal S2=c1×speed command value V+c2 output by the above-mentioned feedforward controller 33, wherein c1 and c2 are constants, can be obtained through the system identification (System Identification) of the system driving transmission device 38, as for the ratio - the first control signal S1 output by the integral controller 32=kp×(speed command value V−speed feedback signal Vf)+ki×(position command value P−position feedback signal Pf)=kp×Vd+ki×Pd, where kp and ki are the gain values of the proportional-integral controller 32 .

The above-mentioned driving transmission device 38 includes a motor driving integrated circuit 380, a DC motor 381 and a transmission mechanism 382, and the transmission mechanism 382 includes a gear set 3820 and a transmission belt 3821, wherein the motor driving integrated circuit 380 receives and controls the first control signal according to the first control signal. The change of S1 and the second control signal S2 corresponds to the driving voltage signal (usually a pulse width modulation voltage signal) required to drive the DC motor 381, and the transmission belt 3821 is used to drive the printing head 39 to move, and the printing Head 39 may be an inkjet head in an inkjet printer.

To sum up, the feed-forward controller 33 added in the present invention can directly compensate the feedback required by the DC motor 381 at a constant speed because the control voltage is generated directly according to the speed command value V output by the path planning unit 30. The electromotive voltage and the voltage required to overcome the dynamic friction between the gear set 3820 and the transmission belt 3821, so the position error and speed error generated by the feedback signal can be effectively reduced, so there is no need to use the proportional-integral controller 32 The gain values kp and ki are designed to be large values, thereby increasing the stability of the system and reducing the speed error of constant speed control. In this way, the reaction speed of the system can be accelerated, and the stability of the system can be increased at the same time, and the speed error of the inkjet head under constant speed control can be effectively reduced.

Of course, the present invention can also be transferred to similar printing devices, such as multi-function business machines, facsimile machines, etc., and the same functional improvement can also be achieved. Therefore, various modifications and changes made by those skilled in the art in the present invention will not depart from the scope of protection intended by the claims of the present application.

Claims (7)

1. A drive control device applied to a print head and a drive transmission device on a printing device, the drive control device comprising: a path planning unit that can output a position command value and a speed command value; a feedback unit, which is connected to the print head signal, and generates a position feedback signal and a speed feedback signal according to the position and speed of the print head; a proportional-integral controller, which is signal-connected to the path planning unit, the feedback unit and the drive transmission, and based on the difference between the position command value and the position feedback signal and the difference between the speed command value and the speed feedback signal generating a first control signal and transmitting the first control signal to the drive transmission; and a feed-forward controller, which is signal-connected to the path planning unit and the driving transmission device, the feed-forward controller receives the speed command value and performs calculation to generate a second control signal and transmits the second control signal to the driving transmission device, Furthermore, the driving transmission device simultaneously drives the printing head to move according to the first control signal and the second control signal. 2. The drive control device according to claim 1, wherein the feedback unit is connected to the optical encoder and the optical scale in the print head, and the optical encoder and the optical scale can reflect the position and speed of the print head . 3. The drive control device as claimed in claim 1, wherein the first control signal generated by the proportional-integral controller is kp×(speed command value-speed feedback signal)+ki×(position command value-position feedback signal), where kp and ki are the gain values of the proportional-integral controller. 4. The driving control device as claimed in claim 1, wherein the second control signal generated by the feedforward controller is c1×speed command value+c2, wherein c1 and c2 are constants and can be passed to the driving transmission device Determined by system identification. 5. The drive control device as claimed in claim 1, wherein the drive transmission device comprises a DC motor and a transmission mechanism. 6. The drive control device as claimed in claim 5, wherein the transmission mechanism comprises a gear set and a transmission belt. 7. The driving control device as claimed in claim 1, wherein the printing head is an inkjet head.

Images