JPS62124548A - Original size detector for original platen movement type copying machine - Google Patents

Abstract

PURPOSE:To eliminate malfunction and to detect original size accurately by providing an original size detecting means, a detecting means which detects an original platen being at a reference position, and a control means which outputs an operation signal to the original size detecting means according to the detection signal. CONSTITUTION:When a copy start button is pressed with an original D of specific size placed on the original platen, the original platen 2 begins to move from its home position to an exposure start position and the original platen detecting means 21 detects the white part 23a of a reference position display plate 23 when reaching the reference position in the middle of the movement. The detection signal is inputted from this original platen detecting means 21 to the control means 25 and the operation signal is outputted from the control means 25 to the original size detecting means 24. Consequently, when the original platen 2 is at the reference position, the size of the original D at the reference position is detected accurately by the detecting means 25.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement in a document size detection device for a copying machine with a movable document table that makes copies by moving the document table.

(Prior Art) Conventionally, in a copying machine with a fixed document table, in order to control automatic cassette 1 selection or automatic double S$ setting, etc. The size of the document is detected by emitting light from a light-emitting device located below the document and detecting the presence or absence of reflected light using light-receiving devices installed at multiple locations. There is. In other words, the reflected light is detected by light receiving devices placed at positions corresponding to the size of the original to be used, and the size of the original is detected by the combination of the light receiving states of each light receiving device. ing.

On the other hand, in a 1j'A manuscript table moving type copying machine, the document table is configured to be movable, so its position is not constant, and even when the document table is stopped, the stop position cannot be specified. Not exclusively. In this way, in a copying machine with a movable document table or
Since the position of the document table is not specified, the document noise detecting means is likely to malfunction, and there is a problem in that it is important to accurately detect the document 1-nice.

(Object of the Invention) The present invention has been made in order to solve the above-mentioned problems, and provides an original document size that can be accurately detected without causing erroneous VJ printing in a copying machine with a movable document table. The purpose is to obtain a size detection device.

(Structure of the Invention) A document size detecting device of the present invention is a movable document table copying machine that makes copies by moving a document table. a11 which outputs an activation signal to the document size detection means in accordance with the detection signal output from the document table detection means which detects that the document table is at the reference position; and the detection signal outputted from the document table detection lower stage;
1t111 means.

With this configuration, the document size detecting means is activated when it is detected that the document table is at the reference position, and the document size detecting means is activated in step 3 above! ! It is possible to accurately detect the size of the document in the base position.

(Miura example) FIG. 1 is a schematic diagram of a copying machine with a movable document table.

Above the body 1 of this copying machine, a document table 2 equipped with a contact glass 2a on which a document D/lit is placed is installed so as to be movable in the left and right directions in the figure. In addition, for compensatory leave 1 above,
A paper feed cassette 3 containing copy paper of different children's sizes is installed, and the copy paper fed out from the paper feed force roller 1-3 via the paper feed roller 4 is transferred to the guide 5, registration roller 6, and transfer. It is configured to be supplied to the transfer section of the photosensitive drum 8 via the front roller 7.

Above the photosensitive drum 8, light is directed toward the original ID.
An optical system section 10 is provided, which includes an exposure lamp that emits light, mirrors tvh, M2, M3, and M4 that guide reflected light from the original document tray, and a lens L1. Further, around the photoreceptor drum 8, a charger 11 for uniformly charging the drum surface and a developing device 13 including a developing roller 12 are provided.
, a transfer charger 14 , a separation claw 15 , and a cleaning amount 16 are sequentially arranged in the rotation direction of the photosensitive drum 80 . The copy paper led out from the transfer section of the photosensitive drum 8 is supplied to the fixing roller 18 via the conveyance mechanism 17, and then transferred to the paper ejection tray 20 by the ejection roller 19.
J:.

Further, the document table 2 is moved from the initial stop position (home position) shown by the solid line in FIG. The photo is placed at the exposure start position opposite to the photo. Thereafter, as the original platen 2 moves to the left in the figure in accordance with the rotation of the photosensitive drum 8, the image of the original platen is transferred to the optical system section 1.
0, the photoreceptor drum 8 is exposed to light.

Further, below the tip of the document table, there is provided an opening detection means 21 consisting of a photosensor. The device is configured to detect that the device is in a position in which the device is moved in the direction of the device. That is, as shown in FIG. 2, a reference position display plate 23 consisting of a white portion 23a and a black portion 23b at the periphery is attached to the lower surface of the periphery of the contact glass 2a, and the document table 2 is placed above the zero position. , the light emitted from the light emitting part 21a of the photosensor hits the white part 23a and is reflected, and the reflected light reaches the light receiving part 2.
By being incident on 1b, it is detected that the document table 2 is at the reference position.

Further, below the document table 2, a plurality of photosensors 24 are provided.
A document size detecting means 24 consisting of a, 24b, and 24c is provided, and is configured to detect 1 size of the original [D] when the document table 2 is at the 1J quasi-position. In other words, each of the photosensors 24a, 24b,
24c is for various sizes (B5.A
4.84) σ) Disposed at a position corresponding to the rear end of the document tray, and controlled by the document tray detection means 21 described in 1. 21
The control means 25 is configured to operate according to the actuation signal 1J outputted from the control means 25 when the detection signal is input to the control means 25.

In the above configuration, when the copy start button is pressed after placing a document tray of a predetermined size on the document table 2, the document table 2 starts moving from the home position to the exposure start position, and during the movement, J3, when the original platen 2 reaches the reference position, the original platen detecting means 21 detects the reference position display plate 2.
A detection signal is inputted from the first stage detection stage 21 of the original platen to the control means 25, and an activation signal is outputted from the control means 25 to the original size detection means 24. As a result, when the document table 2 is at the reference position, the detection means 25 can accurately detect the size of the original f14D at this reference position.

That is, the document table detecting means 21 and the reference position display plate 2
Since the size of the original tray is detected while the position of the original tray 2 is specified by 3, it is possible to prevent malfunctions from occurring. Then, the size of the copy paper to be used is calculated based on the INa document size detection signal and the copy rate setting signal, and copy paper of the corresponding size can be automatically supplied from the paper feed cassette 3. .

In the above embodiment, the reference position d display plate 23 is provided directly on the lower surface of the contact glass 2a, but it may also be directly attached to the lower surface of the frame plate 22 for displaying the document placement position. The structure may be such that it is attached to the bottom surface of the presser foot. Also,
The thickness 1ζl that makes the original size detection means 24 work
FI is not limited to the L-coordinate 1r center, but also the exposure start position J3 and its vicinity. PJJ work has started (can be changed to various positions except the crotch position. Also, other sensors such as a limit switch are used instead of the photo sensor as the document platen detection means 21 for detecting the reference position. It is possible.

(Effects of the Invention) As explained above, in the present invention, the document size detecting means is activated when the document table detecting means detects that the document table is at the 4th position, so that the document table is moved. In a copying machine with a movable document table, the size of the document can be accurately detected while the position of the document table is specified.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view showing an embodiment of the present invention, and FIG. 2 is a plan view of a contact glass.
・・Full-shaped position display board, 24 ・・Document size detection means,
24a, 24b, 24c...photo sensor, 25...
・Control means. Patent applicant Agent: Sanda Kogyo Co., Ltd.
Patent Attorney Etsushi Kotani Patent Attorney Ero Masaru Patent Attorney Yasuo Itaya Figure 2

Claims (1)

[Claims] 1. In a copying machine with a movable document table that makes copies by moving the document table, a document size detection means detects the size of the document placed on the document table, and a document detects that the document table is at a reference position. Document size of a copying machine with a movable document table, characterized in that it is provided with a table detecting means and a control means for outputting an activation signal to the document size detecting means in response to a detection signal output from the document table detecting means. Detection device.