JPS6229359A - Original scanning device - Google Patents

Abstract

PURPOSE:To prevent a wire from being removed by providing stop member stopping one mobile body while other mobile body is brought in the collision state nearly at the same time when one mobile body collides with a device constitution member due to a malfunction. CONSTITUTION:Since the 1st mirror unit A moves in speed twice that of the 2nd mirror unit B, the 1st mirror unit A collides with a device box 1 at the same time when the 2nd mirror unit B collides therewith. Thus, a motor 17 drives large, small pulleys 21, 21' and 22, 22' to inhibit further movement of the 1st and 2nd mirror units A, B, but both the mirror units A, B do not move and a spring has only to be deformed via long/short wires 27, 27' and 28, 28' and the large/small pulleys are not turned. The 1st mirror unit A is moved while the 2nd mirror unit B is not moved and the small pulley is driven. Thus, the removal of the short wire is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a document scanning device used in a copying machine, a laser beam printer, etc., and particularly to a document scanning device that fixes a document and moves an optical system.

(Prior Art) Conventionally, as this type of document scanning device, the scanners shown in FIGS.
In Figure 0, 1 is a machine box, 2 is an original placing glass, 3 is an original, and 4 is an original pressing plate for pressing the original. 5 is a first mirror supported by a support member 7.7' which is slidable along a rail 6.6'. 8 is a lamp that illuminates the original 3; 9 is a lamp cover; the lamp 8 and the lamp cover 9 are fixed to a support member, and move together to form a first mirror unit A. t
o and tt are second and third mirrors, which are supported by support members 13° and 13' which are slidable on the rails 6 and 6'.

Further, the supporting members 13° and 13' are held by a second mirror cover 14, and these move together to form a second mirror unit)B. The first and second mirror units A and B move synchronously in the same direction at a speed ratio of 2:1.

15 is an imaging lens, and 16 is a solid-state image sensor.

17 is a motor, 18 is a timing belt, and 19 is a drive shaft. The drive shaft 19 has a drive pulley 20 and a large pulley 21.
, 21', small pulley 22 having half the diameter of the large pulley
, 22' are fixed and rotate synchronously. 23.23" 24, 24" are tension pulleys, and the rotation shafts 25A, 25A' of the tension pulleys.
, 253, 25B' have springs 26A, 26A''
, 26B, 26B' are attached.

27, 27' are long wires, both ends of which are attached to the first mirror support members 7, 7', and are connected to the large pulley 21.
, 21' several turns, tension pulley 23 , 23 ”
is wrapped half a turn around. Long wires 27, 27
A tension of 3 to 4 kg is applied to ' by springs 26A, 26A'', and when the large pulleys 21, 21' rotate, this rotational force is applied to the support members 7, 7' via long wires 27, 27'. As a result, the first mirror unit A slides.

28 and 28' are short wires, both ends of which are attached to the second and third mirror support members 13 and 13', and are connected to the small pulleys 22 and 22' several times, and the tension pulley 2
4, 24' is wound half a turn. short wire 28
, 28” also has a spring 26B.

26B' applies a tension of 3 to 4 kg, and when the small pulleys 22, 22' rotate, the second mirror unit B
slides.

When the original 3 is set on the original placing glass 2 and the read key (not shown) is pressed, the lamp 8 lights up, and the first
Second mirror unit A.

B starts forward movement at a speed ratio of 2:1. As a result, manuscript 3
The document surface is sequentially and continuously scanned along the longitudinal direction of the lamp 8, and the reflected light from the document surface is transmitted to the first and second
, the solid-state image sensor 16 is exposed to a slit through the third mirror 5, 10.11 and the imaging lens 15, and reading is executed. In the above reading operation, the first mirror unit A and the second mirror unit B move synchronously at a speed ratio of 2:1, so the distance (optical path length) from the document surface to the solid-state image sensor 16 is kept constant. , the original image is exposed to slit light without blur.

When the first and second mirror units A and B reach the reversal position indicated by the broken line in FIG. When the brake is applied, the first and second mirror units A and B stop at the home position shown by the solid line in FIG.

In the case of repeated reading, the above operation is repeated a set number of times.

(Problems to be Solved by the Invention) However, such prior art has the following problems. In other words, if the control device does not operate properly due to sparks or noise, and the motor 17 runs out of control,
Since the distances from the first and second mirror units A and B to the machine box 1 are different, one of the first and second mirror units A and H collides with the machine box 1 first. - For example, if the brake is not applied during the return movement, the second mirror unit B collides with the machine box 1 and stops at this position, but the first mirror unit A is still movable, so the drive of the motor 17 The drive shaft 19 rotates and the first mirror unit A
moves until it collides with machine box L. Meanwhile, the small pulleys 22, 22'' that transmit the driving force to the second mirror unit B rotate, and the short wires 28, 28' are sent, but the second mirror unit B does not move, so the short wires 28, 2
8' becomes slack and comes off from the small pulleys 22 and 22''.

Therefore, even if the control device returns to a normal state, a fatal problem arises in that the document cannot be read.

On the other hand, if the first mirror unit (A) collides with the machine box 1 without the motor 17 rotating in the reverse direction at the reverse position, the long wires 27, 2 that similarly transmit the driving force to the first mirror unit (A)
7' comes off the large pulley 21, 21', causing the same problem as above.

Therefore, in order to solve this problem, as shown in FIGS. 3 and 4, when the first and second mirror units A and B move further than their set positions, the first and second mirror units When mirror units A and B come into contact, motor 1
Switches 29 and 30 were also provided to cut off the power supply to 7.

However, in this case, installation of the switches 29, 30 and wiring are required, creating a new problem that assembly becomes complicated.

The present invention has been made in order to solve the above-mentioned problems of the prior art.The purpose of the present invention is to have an extremely simple structure so that even if the mirror unit malfunctions and collides with the machine box, the wires will come off and the wires will come off. It is an object of the present invention to provide a document scanning device that can prevent the device from becoming unusable due to the inconvenience.

(Means for Solving the Problems) In order to achieve the above object, the present invention has two moving bodies for scanning a document, and the driving force of a motor is transmitted to these moving bodies by separate wires. In a document scanning device that reciprocates the movable body by transmitting the information through It is configured to provide a stop member for stopping the.

(Example) The present invention will be explained below based on illustrated embodiments.

1 and 2 show an embodiment of the document scanning device according to the present invention. In FIG. 0, the same parts as in the conventional device shown in FIGS. In this embodiment, when one mirror unit malfunctions and collides with the machine box, a stop member is provided that stops the movement of the other mirror unit by almost simultaneously bringing it into a colliding state. That is, at the home position shown by the solid line in FIG. A protruding portion 7a serving as a stop member extends to .

7a', and from the tips 7b, 7b' of the protrusion, the machine box 1
The distance is two sentences. Also, at the inverted position shown by the broken line in FIG. 1, one end A' of the first mirror unit is
If the distance from
A damper 31.31'' made of an elastic material such as rubber is fixed on the top, without interfering with the first mirror support members 7, 7', and at a position 2 B'' from one end B'' of the second mirror support member. .

In the above configuration, the document scanning device according to the present embodiment prevents the wire from coming off during malfunction in the following manner. In other words, if the control circuit malfunctions due to sparks, noise, etc., the motor 17 goes out of control and the first and second mirror units/) A and B overrun without stopping or reversing at the home position. In the position, a protrusion 7a is attached to the support member 7° 7' of the first mirror unit so that the distance from the first mirror unit) A to the machine box 1 is twice the distance from the second mirror unit) B to the machine box L. , 7a' are provided, and since the first mirror unit A moves at twice the speed of the second mirror unit B, the first mirror unit A collides with the machine box 1- at the same time as the second mirror unit B. do. Therefore, motor 1
7, the large and small pulleys 21, 21', 22.2
Even if 2' rotates and attempts are made to move the first and second mirror units A and B further, neither mirror unit A nor B will move, and the long and short wires 27.27' and 28°2
8' through springs 26A, 26A'', 26B.

Only 26B' is deformed, large and small pulleys 21°21'
, 22.22'' does not rotate, so.

Although the second mirror unit B does not move, the first
Mirror unit) A moves and small pulleys 22 and 22'
This can prevent the short wires 28, 28' from coming off due to rotation. Furthermore, even if the first and second mirror units A and B overrun without being reversed at the set positions, the first mirror unit A collides with the machine box L and at the same time the second mirror unit support member 13.13'' is damper 3
Collision at 1.31'. Therefore, similarly to the above, the spring 26
A, 26A", 26B, and 26B' are only deformed, and the large and small pulleys 21.21" and 22°22' do not rotate. Therefore, even though the first mirror unit A does not move, the second mirror unit does not move. B moves and large pulley 2
This can prevent the long wires 27 and 27' from coming off due to the rotation of the long wires 27 and 27'.

In addition, in the above embodiment, the first and second mirror units) A,
The distance from B to machine box 1 is 2:1, and both mirror units A and B collide with machine box 1 or damper 31, 31' and stop at the same time, but it is not necessary to do so exactly at the same time.

It is sufficient that the distances are approximately the same, and the distance relationship is approximately 2:1.

Furthermore, in the above embodiment, the first mirror unit and the support member 7
．． 7' is a protrusion 7a serving as a stop member.

Although the case where the protrusion 7a' is provided has been explained, this protrusion 7a' is provided.
A, the first mirror unit at a predetermined position without providing 7a'')A
Of course, a damper may be provided on the rail 6, 6' so that the rails 6, 6' collide with each other.

Further, in the illustrated embodiment, the case where the image of the document 3 is read by the solid-state image sensor 16 has been described, but of course it can also be used when the image of the document 3 is exposed to a photoreceptor.

(Effects of the Invention) The present invention has the above-described configuration and operation, and the stopping member is provided so that when two moving bodies malfunction and run out of control, the re-moving bodies stop almost simultaneously. Even though one moving body has stopped first, the other moving body moves and creates slack in the wire that drives the moving body that stopped first, thereby preventing the wire from coming off. This can prevent the device from becoming unusable.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an embodiment of a document scanning device according to the present invention, FIG. 2 is a perspective view showing the main parts of the same device, FIG. 3 is a schematic diagram showing a conventional document scanning device, and FIG. The figure is a perspective view showing the main parts of the device. Explanation of symbols 1...Machine box (equipment component) 3...Documents 7a, 7a'...Protruding parts (stopping members) 17...Motor

Claims (1)

[Claims] In a document scanning device that has two movable bodies for scanning a document and transmits the driving force of a motor to these movable bodies through separate wires, the movable bodies are reciprocated. 1. A document scanning device characterized in that a stopping member is provided for stopping the movement of another movable body by bringing the other movable body into a collision state almost simultaneously when one of the movable bodies collides with a device component member.