JPH01115669A - Driving controller - Google Patents

Abstract

PURPOSE:To prevent a difference in driving speed from being generated between driving bodies even in a transient state, by providing one of driving bodies the load on which is lower than the load on the other driving body with a means for exerting a load difference, and exerting a load on the driving body receiving the lower load for a predetermined period of time when the driving bodies are started and when the driving bodies are stopped. CONSTITUTION:In a driver for a printer comprising four photosensitive drums 3A-3D and a feeding belt 1 for feeding a transfer paper 14 in contact with the drums, the load on a motor provided with a belt-driving roller M1 is lower then the load on a motor for driving the drums 3A-3D. A torque brake 20 is provided for a roller shaft 19 between the belt-driving motor 18 and the belt-driving motor M1, and the torque brake 20 is so operated that equal loads are exerted on both the driving body for the drums and the driving body for the belt. The torque brake 20 is energized for a predetermined period of time in a transient state when the belt-driving motor 18 and the drum-driving motor are started and when the motors are stopped, whereby rise and fall conditions with the same velocity change can be maintained between the feeding belt 1 and the drums 3A-3D.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a drive control device, and more specifically, the present invention relates to a drive control device, and more specifically, it is possible to control drive control devices that have different torques and loads that are driven at a constant speed while in contact with each other. The present invention relates to a drive control device for eliminating inconveniences caused between the two.

[Conventional technology]

2. Description of the Related Art Conventionally, in recording apparatuses such as copying machines and printers, a photosensitive drum and a transfer paper conveying belt are driven by individual drive motors, that is, a drum drive motor and a belt drive motor, while maintaining contact with each other. By the way, various measures have already been taken to address the problems caused by differences in operating speeds in such drive devices.For example, in the case of the above-mentioned recording device, the There is no problem because the rotation speed is controlled by the servo circuit, but there is no control when each motor starts (when the speed rises) and when it stops (when the speed falls), so when the load is different In the above case where the drive bodies are driven by respective drive sources, there is a difference in the time required for starting and stopping.

[Problem that the invention seeks to solve]

However, in the past, performance in such a transient state before and after normal rotation and measures to improve it have been left unresolved, apart from improvements such as time reduction. Therefore, due to the difference in time required for starting or stopping as described above, the driving bodies come into sliding contact with each other during that time.
If scratches occur on the contact surfaces of both sides, or if one of the drive bodies is a belt, etc., it will bend due to its flexibility and come in contact with other parts, causing damage or if the drive body is perpendicular to the drive body. There was a problem in that the paper was lopsided in one direction, causing problems with transportation.

An object of the present invention is to focus on the above-mentioned conventional problems, and in order to solve the problems, by making the rise and fall times of each drive motor constant, even in the transient state before and after the operating state at a stable speed. An object of the present invention is to provide a drive control device that prevents a difference in drive speed between drive bodies.

[Means for solving problems]

In order to achieve such an object, the present invention aims to reduce the speed rise and rise caused by the difference in load between a plurality of drive bodies when starting and stopping a plurality of drive bodies driven by different drive sources while maintaining contact with each other. In a drive control device that controls descent, a means for applying a difference in load is provided on the drive body with a lower load, and the means for applying a difference in load when starting and stopping the drive body is used to apply a difference in load to the drive body with a lower load. This feature is characterized in that a load is applied for a predetermined period of time.

[For production]

According to the present invention, a load corresponding to the lower load is applied by the load applying means to the driving body with a lower load during a certain period of time required for the speed to rise and fall during driving and stopping. It is possible to maintain a constant speed at the rise and fall between both sides when stopped, which prevents inconveniences caused by sliding friction between the driving bodies, and deflection if one of the driving bodies is a belt, etc. It is possible to prevent transport defects from occurring due to

〔Example〕

Embodiments of the present invention will be described in detail and specifically below based on the drawings.

FIG. 1 shows an embodiment in which the present invention is applied to a printer drive device having four photosensitive drums and a conveyor belt that conveys a transfer sheet in contact with these drums.

In Figure 1, Ml is the torque brake and motor (
(not shown); 1 is a conveyor belt;
2 is a belt roller, and 3A to 3D are photosensitive drums.

Note that the drive motor for each drum and the speed detector for each motor are located inside each motor and are therefore not shown. 7 is an image transfer charger, 8 is a printing unit, 9 is a charger,
1o is a developing unit, 11 is a drum cleaning unit, 12 is a fixing unit, and 13 is a paper discharge tray.

The transfer paper 14 is sent out from the storage cassette 15 by the paper feed roller unit 16 and is temporarily stopped at the position of the registration rollers 17. Here, the registration roller 17 is interlocked with a registration clutch (not shown), and at a predetermined pre-programmed timing, applies power from, for example, a fixing drive motor or a drum drive motor through the registration clutch. It is transmitted to the registration roller 17, rotates it, and sends out the transfer paper 14.

Further, a latent image is formed on the photoreceptor drums 3A to 3D through a charging process by each charger 9 and an exposure process by the printing unit 8. , the latent image is visualized and a toner image is created. Therefore, an image is formed on the transfer paper 14 by transferring this toner image to the transfer paper 14 by the image transfer charger 7, and a yellow image is created by this first photosensitive drum 3A. As the conveyor belt 2 moves, the transfer paper 14 is sent to the second photosensitive drum 3B, and the magenta image is transferred to the same transfer paper 1.
4 by the same process. Thereafter, a cyan image is created on the third photosensitive drum 3C, and a black image is created on the fourth photosensitive drum 3D, completing a color print.

Thereafter, the transfer paper 14 is fixed by the fixing unit 12, discharged outside the machine, and stored in the paper discharge tray 13. In this case, a motor that drives each photosensitive drum 3A to 3D and a belt drive roller 9M1 are used. When compared with a motor, the belt drive element has a lighter load than the photosensitive drum drive motor. Further, since the conveyor belt 1 contacts each of the four photosensitive drums 38 to 3D and moves at the same relative speed, it is subjected to a large tensile force, and the conveyor belt 1 is likely to be deflected or shifted.

Therefore, in this embodiment, as shown in FIG. 2, the roller shaft 1 between the belt drive motor 18 and the belt drive roller Ml is
9 is provided with a torque brake 20, and this torque brake 2
0 so that the same load is applied to both driving bodies, and the torque brake 20 is, for example, a powder brake, a powder clutch, or an electromagnetic brake. Thus, by energizing the torque brake 20 at the timing shown in FIG. 3, that is, for a certain period of time during the transient periods when the belt drive motor 18 and the drum drive motor are started and stopped, the conveyor belt 1 and the photosensitive drums 3A to 3D are connected to each other. During this period, the rising and falling states can be maintained with the same speed change.

Note that the torque brake 20 is one that generates enough torque to eliminate the difference in torque between the belt drive motor 18 and the drum drive motor due to their torque characteristics. is maintained uniformly, and the above-mentioned inconveniences occurring between the driving bodies can be eliminated.

FIG. 4 shows another embodiment of the invention. This example shows a suitable example when there is not only a difference in torque between the motors but also a difference in inertia load between both driving bodies. There is a big difference in inertia. Therefore, the inertial force is balanced by giving the belt drive roller Ml, which has a smaller inertial force, a larger inertial force.Here, 21 is a flywheel for obtaining an inertial load, and 22 is a clutch. Note that in this example, the torque brake 20 may be omitted if there is no difference in transient torque between the motors. In this example, the inertia is adjusted by turning on and off the clutch 22 during a transient period.

Next, still another embodiment will be described with reference to FIG.

In FIG. 1, reference numeral 23 denotes a belt cleaning blade, and the blade 23 is pressed against the conveyor belt 1 during transient periods by a driving means 24 such as a solenoid, and the load is adjusted so as to be balanced. In the case of this example as well, it goes without saying that it can be used in combination with the torque brake 20 and the flywheel, or can be installed alone.

Note that although the above embodiment was applied to a recording device having a plurality of photosensitive drums and one conveying means, the application of the present invention is not limited to this, and can be applied to a general recording device of this type. Of course, it can be widely applied to cases where speed synchronization is required at the rise and fall of speeds of drive devices that are in contact with each other and driven at the same speed at the same time.

〔Effect of the invention〕

As described above, according to the present invention, the speed rise and During the fall, we have provided a means to add a difference in load to the side with the least load so that the load applied to both drive bodies is the same, so damage caused by sliding contact between the drive bodies when starting or stopping is provided. In the case where one of the driving bodies is a conveyor belt, it is possible to prevent the belt from sagging or shifting and causing problems to the apparatus. Furthermore, if the present invention is applied to a recording apparatus having this type of driving means, it can contribute to maintaining high quality recording by keeping the conveyor belt in a normal state.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an outline of a four-color recording device according to the present invention, FIG. 2 is a perspective view showing a brake means in an embodiment of the present invention, and FIG. 3 is a brake supplied to the brake means. FIG. 4 is a timing chart showing the signal timing, and is a perspective view showing the flywheel installed and folded as another embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Conveyance belt, Ml... Drive roller, 38-3D... Photosensitive drum, 19... Roller shaft, 20... Torque brake, 21... Flywheel, 22... Clutch, 23... Belt cleaning blade, 24... Solenoid.

Claims (1)

[Claims] Drive control that controls the rise and fall of speed caused by the difference in loads when starting and stopping a plurality of drive bodies driven by different drive sources while maintaining contact with each other. In the apparatus, means for applying the load difference is provided on the drive body with a lower load, and the means for applying the load difference when starting and stopping the drive body applies the load difference to the drive body with a lower load. A drive control device characterized in that the load is applied for a predetermined period of time.