JPH049289B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to driving a document placing table of an electronic copying machine, and more specifically, to driving a document placing table of an electrophotographic copying machine that performs slit exposure by reciprocating movement of the document placing table. It is something.

In conventional electronic copying machines that perform slit exposure by reciprocating the document table, there are various methods for driving the document table, such as driving the document table by a main drive motor via a clutch or gear; There are methods such as variable speed control of a dedicated drive motor and methods of driving the document table using reversible rotation. However, in the first method using a clutch, power is transmitted from the main motor to the document table via a chain, gears, etc., which causes problems such as an increase in the number of parts and an increase in the space required. There is a drawback that it is difficult to control changes in the moving speed of the document table. Furthermore, the second method using a dedicated motor is also unsatisfactory in terms of speed, accuracy, and reliability because it requires a reduction mechanism using gears or the like. As a way to solve the problems of these methods, Japanese Patent Application Laid-Open No. 55-2273 discloses a highly reliable and compact document platform drive device that can easily change the speed without using a clutch or a special motor. has been done. In this third type, a linear pulse motor is used to control the operation of the optical system of a copying machine, and a document scanning mirror is combined with a slider, and a stator is attached to the copying machine body facing the slider. , a predetermined electric pulse is applied to the magnetic pole piece (permanent magnet) that makes up the slider to move the slider forward one by one in accordance with the pitch of the stator, and when the forward stroke is completed, a limit switch is activated and a reverse pulse is applied. The switch is switched and the backward process is performed. However, in this third method, since the slider is connected to the optical system that is the driven part, a power supply cable for feeding power to the slider must accompany the movement of the slider, and therefore the distance traveled by the slider is When the power supply cable was large, it was necessary to prevent the power supply cable from getting caught in the slider.

In order to obtain a drive device that does not have the above-mentioned drawbacks in the prior art when driving an original platen, the present invention integrates and attaches the stator of a linear pulse motor to the original platen, and replaces the magnetic pole piece conventionally used as a slider. By attaching the power supply cable to the copying machine body facing the stator, there is no need to move the power supply cable for feeding power to the magnetic poles, and it is possible to prevent the power supply cable from becoming entangled in the copying machine body and resulting malfunctions. The present invention provides an original document placing table device which is structurally simpler than a conventional document placing table drive mechanism and can perform copying operations extremely smoothly.

The present invention will be explained in detail below with reference to the drawings.

FIG. 1 is a partially cutaway view of the document placement table according to the present invention, in which a stator 2 of a linear motor is attached to the side edge of the document placement table (platen glass) 1 along the direction of movement of the document placement table. A magnetic pole piece 3 (consisting of four permanent magnets in the figure) is attached to the main body of the copying machine so as to face the stator 2 at approximately the center of the movement range of the stator. FIG. 2 is a side view of the document table, in which the stator 2 attached to the document table is arranged facing the magnetic pole piece 3,
A document mounting table is supported by a slide bearing 4, and a certain amount of space is formed between the stator and the magnetic pole pieces.

The driving of the document table according to the present invention is performed, for example, as follows. In FIG. 3, magnetic poles 31, 32 and 33, 34 of the magnetic pole piece 3 connected to the power source 5 are provided with coils, respectively, to form electromagnets. The distance between the poles of each electromagnet is a size corresponding to a single pitch between the teeth 21 of the stator 2, and the distance between the magnetic poles of one electromagnet (for example, 3
1) is exactly opposite one tooth of the stator, the magnetic poles 33, 34 of the other electromagnet are not in a position opposite to the tooth of the stator. When a forward pulse current is alternately applied to each electromagnet from the power supply 5, both electromagnets are alternately charged with magnetic force and sequentially move the teeth 21 of the stator 2 in one direction (for example, to the left), so that the document connected to the stator is The mounting table also moves in the same direction as the stator. When the leftward movement is completed, the limit switch is activated to switch to the reverse pulse current, and the stator and document table are moved rightward. When the document table reaches the right end, the limit switch is operated again and the current is switched to the forward pulse current, thus allowing the document table to reciprocate.

As described in detail above, according to the document mounting table of the present invention, the magnetic pole is fixed to the copying machine body, and the document mounting table to which the stator is attached is configured to reciprocate. There is no need to move the power supply cable for supplying power to the magnetic poles when moving the document table, and it is possible to prevent the power supply cable from getting caught in the copier body and the resulting malfunctions, and it is possible to prevent the power supply cable from getting caught in the copying machine body and the resulting malfunctions, and it is possible to prevent the power supply cable from getting caught in the copying machine body and the resulting malfunction. It has the advantage that it is structurally simpler than the drive mechanism of the previous example, and that copying operations can be performed extremely smoothly.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a document placing table of the present invention, FIG. 2 is a side view, and FIG. 3 is a diagram for explaining the driving of the document placing table. Symbols in the figure: 1...Original table, 2...Stator, 3...Magnetic pole piece, 4...Slide bearing,
5...Power supply.

Claims (1)

[Claims] 1. In a document tray drive device of a copying machine that performs slit exposure by reciprocating the document tray, the stator of a linear pulse motor is attached to the side edge of the document tray along the direction of movement of the document tray. 1. A document mounting table driving device, characterized in that a magnetic pole of a motor is fixedly mounted on a copying machine main body so as to face the stator and form an air gap.