JP2532244Y2 - Document guide plate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an original guide plate, and more particularly, to an original guide plate for preventing a contact glass from falling.

(Prior Art) A glass called a contact glass is used in an image reading unit of a facsimile apparatus or the like. In addition to transmitting reflected light from the surface, it also plays a role in preventing dust, paper dust, dirt, and the like from falling into devices disposed below the contact glass. The contact glass is held by a document guide plate, and the document guide plate guides the conveyed document to the contact glass. FIG. 3 shows such a conventional configuration using a document reading mechanism such as a facsimile machine as an example.

In FIG. 3, reference numeral 1 denotes a document reading mechanism such as a facsimile apparatus. The document reading mechanism 1 includes document conveying rollers 2a and 2b.
The original 4 is conveyed, for example, in the direction of the arrow in the figure by the driven rollers 3a and 3b, and the conveyed original 4 is guided to the contact glass 6 by the original guide plate 5. Light from a light source 7 irradiates the original surface 4a of the original 4 guided by the contact glass 6, and this light is reflected on the original surface 4a. Photoelectric conversion is performed. By this photoelectric conversion processing, an image on the document surface 4a facing the contact glass 6 is read.

4 to 6 are views showing the configurations of the document guide plate 5 and the contact glass 6, and the contact glass 6 is a holding portion formed in the opening 5b of the guide plate 5a of the document guide plate 5.
5c, 5d, glass holders 11a, 11b and screws 12
Fixed by a, 12b. FIG. 7 is a sectional view showing the structure of a case of fixing the contact glass 6 the document guide plate 5, the opening portion 5b of the guide plate 5a has a width l ₁ to collect sufficient amount of light on the document surface 4a is set For example, l ₁ = 5 to 6 m
m. The thickness of the contact glass 6 is 2 to 3 mm, and protrudes from the guide plate 5a by about l ₂ = 1 mm. The original reading width l ₃ of the contact glass 6 is usually l ₃ =
210 mm, 81/2 ″ paper for overseas machines, usually l ₃ = 216 m
m.

(Problems to be Solved by the Invention) However, in such a conventional document guide plate, the length of the opening in the longitudinal direction (reading width direction) is sufficiently longer than the length of the contact glass. ,
When attaching the contact glass or removing it when cleaning the inside of the contact glass, the contact glass may be dropped into the device from the opening, causing the contact glass to break or the document guide plate to be removed and taken out. I was

(Purpose of the Invention) Therefore, in the present invention, by providing a projection protruding in the guide direction at the side end of the holding member, the contact glass falls into the device through the gap between the side ends of the pair of holding members. The present invention provides a document guide plate that can reduce the cost of the contact glass by using a contact glass whose length in a direction orthogonal to the guide direction in which the document is guided can be shorter than the length of the opening. It is intended to be.

In order to achieve the above object, the present invention provides a guide plate for guiding a document in a predetermined direction, and a guide for irradiating light from a light source with a predetermined reading width to a document surface facing the guide plate. An opening formed in the plate, a pair of holding members provided in the opening extending in a direction orthogonal to the guide direction in which the document is guided, and provided in the opening so as to face each other at a predetermined distance from each other; A contact glass that is in contact with the surface of the original opposite to transmit light from the light source and reflected light from the original surface, and that has a length in a direction orthogonal to the guiding direction in which the original is guided is shorter than the length of the opening; A document guide plate that holds the contact glass with the holding member and guides the document while passing over the contact glass, protruding in the guide direction at one or both side ends of the holding member. Provide protrusions and contact When the glass is displaced in a direction perpendicular to the guiding direction, the lower surface of the contact glass contacts the protrusion to prevent the contact glass from dropping.

 Hereinafter, the present invention will be specifically described based on embodiments.

 1 and 2 show an embodiment of the present invention.

In FIG. 1, reference numeral 21 denotes an original guide plate, and the original guide plate 21 is formed of a guide plate 21a on which an original is conveyed. The guide plate 21a receives light from a light source (not shown) at a predetermined scanning width. An opening 21b is formed so as to irradiate light. Further, holding portions (holding members) 21c and 21d are formed in the opening 21b so as to hold a contact glass (not shown), and the contact glass is set and fixed in the holding portions 21c and 21d. Contact glass is guide plate 21a
The light from the light source is transmitted while the light from the light source is transmitted, and the light reflected from the original surface is transmitted. Further, the contact glass prevents dust, paper dust, dust and the like from dropping into a device such as a facsimile machine. Further, protrusions (protrusions) protruding in the document guide direction are provided at both end portions in the reading width direction of the holding portion 21c as shown in FIG.
21e and 21f are formed, and the projections 21e and 21f prevent the contact glass from falling into the device.

 Next, the operation will be described.

The document conveyed to the document guide plate 21 is guided by a contact glass by a guide plate 21a, and light is emitted from a light source through an opening 21b to a document surface in contact with the contact glass. This light is reflected on the document surface, and the reflected light is transmitted through a predetermined optical system (mirror, lens, etc.) to a CCD (Charge Coupled).
Device) or the like, and the original image is read.

If the document guide plate 21 has a large document passing amount, it is necessary to clean the contact glass every fixed maintenance period. Guide glass for contact glass during cleaning 21a
However, since the protrusions 21e and 21f are formed on the holding portion 21c, it is possible to prevent the contact glass from falling into the device. Also, it is possible to prevent falling when mounting. Therefore, the protrusions 21e, 2
By forming 1f, the guide plate 21a can be used when assembling the contact glass to the document guide plate 21 or removing it during cleaning.
It is possible to prevent the contact glass from falling into the device from the opening 21b.

In this embodiment, the projections 21e and 21f are provided on the holding portion 21c. However, the present invention is not limited to this.
May be provided in the same manner.
It goes without saying that the protrusions may be provided on both or only one of 1d.

(Effect) According to the present invention, since the protrusion protruding in the guide direction is provided at the side end of the holding member, it is possible to prevent the contact glass from falling into the device through the gap between the side ends of the pair of holding members. Therefore, the cost of the contact glass can be reduced because a contact glass whose length in a direction orthogonal to the guide direction in which the document is guided is shorter than the length of the opening can be used.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 and 2 are views showing an embodiment of a document guide plate of the present invention, FIG. 1 is a plan view showing the configuration thereof, and FIG. is there. 3 to 7 are views showing a conventional document guide plate.
3 is a configuration diagram of a document reading mechanism to which the document guide plate is applied, FIG. 4 is a perspective view thereof, FIG. 5 is a plan view thereof, FIG. 6 is a sectional view taken along the line AA 'of FIG. FIG. 7 is a sectional view of the main part. 21… Original guide plate, 21a… Guide plate, 21b… Opening,
21c, 21d ... holding part (holding member), 21e, 21f ... projection part (projection).

Claims (1)

(57) [Scope of request for utility model registration] A guide plate for guiding a document in a predetermined direction; an opening formed in the guide plate so as to irradiate light from a light source with a predetermined reading width on a document surface facing the guide plate; A pair of holding members, which extend in a direction perpendicular to the guiding direction to be guided and are provided in the opening so as to face each other at a predetermined distance from each other, and contact a document surface facing the opening with a light source. And a contact glass, which transmits the light reflected from the document surface and has a length shorter than the length of the opening in a direction orthogonal to the guide direction in which the document is guided, and the contact glass is provided with the holding member. In a document guide plate that guides the document while passing it over the contact glass, a projection protruding in the guide direction of the holding member is provided at one or both side ends of the holding member, and the contact glass is In the guide direction Original guide plate, wherein a lower surface of the contact glass when shifted in the direction orthogonal to as the contact glass in contact with the protrusion is prevented from falling.