JPH03244270A - Image reader - Google Patents

Abstract

PURPOSE:To surely stick every kind of original to a supporting member with an appropriate pressing force by providing a switching means to change the pressing force of a pressing means to press the original to stick to the supporting member based on the kind of the original. CONSTITUTION:A pressing member 12 which comprises the pressing means to press a fed original 9 so as to stick to platen glass 10 is provided at the upper side of the platen glass 10. The pressing member 12 is pressed downward with plural springs 13 provided in a longitudinal direction, which makes the original 9 stick to the platen glass 10 with the pressing force of the springs 13 via the pressing member 12. The switching means to change the pressing force of the spring 13 according to the kind of the original 9 is provided at the upper side of a spring holding means 14. When a thick original 9 is fed, the original 9 can be stuck to the platen glass 10 by moving a sliding lever 16 manually in a direction of arrow head D, and engaging a clicking spring 18 with a groove 16c, and intensifying the pressing force of the spring 13.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an image reading device having a document reading system such as a facsimile, a copying machine, an image reader, or the like.

<Prior Art> Conventionally, in image reading devices such as facsimile machines and copying machines, in the document reading system, the document is conveyed to the optical reading system at a predetermined speed by a conveyance means, the contents are read, and image information is obtained. is configured to send the information to the recording system.

As shown in FIG. 4, the document reading system includes a document loading table 5
The original document 51 fed from 0 is fed to the downstream side by a pre** feed roller 52a and a pressure contact member 52b in pressure contact with this, and then separated one by one by a separation roller 53a and a separation pressing piece 53b in pressure contact therewith. After that, it is configured to be transported to the reading position by a pair of transport rollers 54.

At the reading position, a platen glass 55 is arranged horizontally with respect to the conveying direction of the original 51. This platen glass 55 is held by a contact type image sensor 56. A pressing member 57 for pressing the original 51 against the platen glass 55 is provided above the platen glass 55, and a constant pressing force is applied to the pressing member 57 by a spring 58. The pressing member 57 is made of a white member so as to serve as a reference when reading the original image.

The original 51 conveyed by the pair of conveying rollers 54 is pressed onto the platen glass 55 by the pressing member 57, and the original image is read by the image sensor 56. The original 51 whose image has been read is then discharged to a discharge tray (not shown) or the like by a pair of discharge rollers 59 arranged on the downstream side.

<Problems to be Solved by the Invention> However, in the above-mentioned prior art, the document 51 is configured to be brought into close contact with the platen glass 55 by the pressing member 57 urged by the spring 58; By setting the pressing force 58, a thin original 51 can be brought into close contact with the platen glass 55, but a stiff and thick original 51 may not be brought into close contact with the platen glass 55. In this case, the read image may become blurred.

Conversely, if the pressing force of the spring 58 is set for the thick original 51, the pressing force of the spring 58 is set for the thin original 51.
5, the paper cannot be transported between the
There was a risk that this would occur.

An object of the present invention is to solve the above-mentioned problems of the prior art, and to provide a switching means for changing the pressing force of the pressing means that presses the original, so that even when conveying all kinds of originals, the support member can be adjusted with an appropriate pressing force. An object of the present invention is to provide an image reading device that can be conveyed in close contact with an image reading device.

<Means for Solving the Problems> Means for solving the above problems of the prior art and applicable to the embodiments described below include a support member for holding a document placed at an image reading position, and a support member for holding a document placed at an image reading position; a pressing means for pressing the image of the original onto the supporting member; a reading means for reading the image of the original conveyed onto the supporting member; and a switch for changing the pressing force of the pressing means depending on the type of the original. It is characterized by having a means.

<Function> According to the above means, since the switching means is provided to change the pressing force of the pressing means for pressing the original so that it comes into close contact with the support member, depending on the type of the original, it can be applied to any type of original. It can be reliably brought into close contact with the support member by applying an appropriate pressing force.

Therefore, image quality can be improved by preventing blurring of the read image and poor conveyance due to floating of the original.

<Embodiment> An embodiment of an image reading device to which the present invention is applied will be described below with reference to the drawings. In this embodiment, a facsimile device will be explained as an image reading device.

FIG. 1 is an explanatory cross-sectional view showing the document reading system, FIG. 2 is an explanatory view showing the structure of the switching means for changing the pressing force of the pressing means,
FIG. 3 is an explanatory cross-sectional view showing the schematic structure of the fudge removal device.

First, a schematic configuration of a facsimile machine to which the present invention is applied will be explained with reference to FIG.

This facsimile machine is composed of a recording system A and a document reading system B.

First, to explain the recording system A, 1 is a thermosensitive recording sheet that develops color by applying heat, and a sheet roll 1b in which a long sheet is wound in a roll shape around an inner core 1a is stored in a drop-in type roll holder 2. An image is recorded on the recording sheet 1 pulled out from the sheet roll 1b, which will be described later, in a recording section 3, which will be described later. The sheets are cut from the rear end and are discharged onto a reversing tray 7 by a discharge roller 6 and stacked.

To explain the configuration of the recording unit 3, the recording unit 3 has heat generating elements arranged in a line that individually energize and generate heat according to image information on the surface of a platen roller 3a which is driven by a drive source (not shown) and also serves as a conveying means. 3b is pressed by a pressing spring 3C.

Therefore, an image is recorded on the recording sheet 1 by rotating the platen roller 3a in the direction of the arrow a to convey the recording sheet 1, and in synchronization with this, causing a heating element to generate heat according to the image signal. It is.

Next, to explain the document reading system B, the document 9 loaded on the top cover 9a of the facsimile machine is pressed against the pre-OI conveyance pressing piece 8a and the preliminary conveying roller 8b that presses against this, and the separation pressing piece 8C and this. After the sheets are separated one by one by a separation roller 8d, they are further conveyed to the image reading position 1c on the downstream side by a pressing roller 8e and a conveying roller 8f pressed against the pressing roller 8e.

A platen glass 10 is a support member for supporting the original 9 placed at the image reading position C.

This platen glass 10 is integrally held by a contact type image sensor 11 which is a reading means for reading an original image.

On the upper side of the platen glass 10, there is a document 9 that has been conveyed.
A pressing member 12 is provided, which constitutes a pressing means for pressing the platen glass 10 so that it comes into close contact with the platen glass 10. A white pressing member 12 is used to serve as a reference for the read image. The pressing member 12 is urged downward by a plurality of springs 13 provided in its longitudinal direction, and the pressing force of the springs 13 causes the original 9 to come into close contact with the platen glass 10 via the pressing member 12. .

The spring 13 is held by a spring holding member 14 that is arranged to be able to swing up and down.

Further, above the wing holding member 14, there is provided switching means, which will be described later, for changing the pressing force of the wing 13 depending on the type of the document 9.

The document image of the document 9 conveyed onto the platen glass 10 is read by the contact type image sensor 11 .

The contact image sensor 11 mainly uses a short-focus imaging lens with a very shallow depth of field, such as Selfoc Lens Array (trade name), and is configured to read a document image. This image information is configured to be transmitted to its own recording unit in the copy mode, and to the recording unit of another device in the facsimile mode.

After the image has been read, the original 9 is conveyed by the pressing roller 8g and the ejection roller 8h, and is ejected onto the ejection tray 81.

Next, the structure of the switching means for changing the pressing force of the spring 13 will be explained with reference to FIGS. 1 and 2.

In FIG. 2, a long shaft-shaped blade member 15 is attached above the spring holding member 14, with one end supported by a stay 15a and the other end supported by a support member 15b. Cams 15c are attached to positions of the wing member 15 corresponding to the blades 13, respectively. The support member 15b is rotatably connected about a support shaft 16a to a slide lever 16 that is movable in the direction of arrow E in the figure. The slide lever 16 has an elongated hole 16b bored in its side surface in the horizontal direction, and is supported by inserting guide pins 17a and 17b attached to the main body of the device into the elongated hole 16b. The movement range in the E direction is defined.

When the slide lever 16 is moved in the direction indicated by the arrow, the support member 15b rotates clockwise around the support shaft 16a, and in conjunction with this, the wing member 15 also moves in the same direction. The cam 15c comes into contact with the spring holding member 14, compresses the spring 12, and increases the pressing force.

Further, when the slide lever 16 is moved in the direction of arrow E, the support member 15b rotates counterclockwise around the support shaft 16a, and in conjunction with this, the wing member 15 also rotates in the same direction. As a result, the cam 15c is separated from the spring holding member 14, and the spring holding member 14 is pushed upward, and the spring 13 is extended in the vertical direction, so that the pressing force is weakened.

A groove 16c is provided at the lower edge of the slide lever 16.

16d, and by engaging click springs 18 with these grooves 16c and 16d, the position of the slide lever 16 is fixed and the pressing force against the spring 13 is switched. The click spring 18 is constituted by a plate spring or the like screwed onto the chassis 18a of the main body of the apparatus.

According to the above configuration, as shown in FIG.
When transporting the slide lever 16, manually move the slide lever 16 in the direction of the arrow to insert the click spring 18 into the groove 16c.
By engaging the members and increasing the pressing force of the spring 13, the document 9 can be brought into close contact with the platen glass 10 via the pressing member 12 with an appropriate pressing force.

When transporting a thin document 9, the slide lever 16 is manually moved in the direction of the arrow E to engage the click spring 18 in the groove 16d and weaken the pressing force of the spring 12, so that an appropriate The original 9 can be brought into close contact with the platen glass 10 via the pressing member 12 with a pressing force.

Therefore, the original 9 can be brought into close contact with the platen glass IO with an appropriate pressing force depending on the type of original 9. Moreover, this makes it possible to prevent distortion and poor conveyance of the read image at the image reading position C, thereby improving the image quality.

Incidentally, in the above embodiment, the pressing force was configured to be switched in two stages for thick and thin documents.
Furthermore, it is also possible to configure the pressing force to be switched in multiple stages.

Further, although the pressing force is switched manually, it is also possible to switch it automatically using an actuator that operates in conjunction with an operation key or the like.

Further, in the above embodiment, a contact type image sensor is used as the reading means, but the present invention is not limited to this, and can be applied to other devices having a relatively long optical path length, for example. Furthermore, although a facsimile machine has been described as an image reading device, other devices such as image readers can also be used.

<Effects of the Invention> As described above, the present invention is provided with a switching means that changes the pressing force of the pressing means for pressing the original so that it comes into close contact with the support member, depending on the type of the original, so that it can be applied to any original. It is also possible to reliably bring it into close contact with the support member with an appropriate pressing force.

Therefore, image quality can be improved by preventing blurring of the read image and poor conveyance due to floating of the original.

[Brief explanation of drawings]

FIG. 1 is an explanatory cross-sectional view showing the document reading system, FIG. 2 is an explanatory view showing the structure of the switching means for changing the pressing force of the pressing means,
FIG. 3 is an explanatory cross-sectional view showing a schematic configuration of a facsimile machine, and FIG. 4 is an explanatory view of a conventional example. A is a recording system, B is a document reading system, 1 is a thermal recording sheet, l
a is the inner core, 1b is the sheet roll, 2 is the roll holder,
3 is a recording unit, 3a is a platen roller, 3b is a recording head, 3c is a pressing spring, 4 is a guide member, 5 is a cutter, 6 is a discharge roller, 7 is a reversing tray, 8a is a preliminary conveyance pressing piece, 8b is a preliminary conveyance Roller 8c is a separation pressing piece 8
d is a separation roller, 8e is a pressing roller, 8f is a conveyance roller,
8g is a pressing roller, 8h is a discharge roller, 81 is a discharge tray, 9 is a document, 10 is a platen glass, 11 is an image sensor, 112 is a pressing member, 13 is a spring, 14 is a spring holding member, 15 is a wing member, 15a is a stay, 15b is a support member, 15c is a cam, 16 is a slide lever 16a, 16b is a long hole, 16c and 16d are grooves, and 17a. 17b is a guide bin, 18 is a click spring, and 18a is a chassis. Figure 2

Claims (1)

[Scope of Claims] A support member for supporting a document placed at an image reading position; a pressing means for pressing the document so that it comes into close contact with the support member; and a document conveyed onto the support member. An image reading device comprising: a reading means for reading an original image; and a switching means for changing the pressing force of the pressing means depending on the type of the original.