JP2000258857A - Original guide - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily and accurately fix an original guide (original scale) used as original butting reference at a specified position on a housing at the time of assembling an image reader and at the time of maintaining it in the image reader equipped with a contact glass as an original set board. SOLUTION: This original guide is constituted of a narrow plate-like part 11 equipped with a reference edge 11a being the original butting reference, and an attaching piece 12 protrusively provided at the other edge 11b of the narrow belt-like part 11. Then, a screw hole 13, a U-shaped hole 14 and a tapered shape part 15 are formed on the attaching piece 12. A screw hole 20 matched with the screw hole 13 of the attaching piece 12 and a projection 21 seated in the U-shaped hole 14 are formed at the proper spots of the periphery of an aperture part formed on the upper surface of a device-side frame 2 in a specified arranged state, and the tapered shape part 15 communicates with the U-shaped hole 14 and is formed so that its inside diameter is gradually increased as it is separated from the U-shaped hole 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a document guide (document scale) used as a document abutting reference in an image reading apparatus having a contact glass as a document setting table, and more particularly, to a method of mounting a document guide on a housing. 1. Field of the Invention The present invention relates to a document guide that can secure positional accuracy when fixing a document at a predetermined position.

[0002]

2. Description of the Related Art In an image forming apparatus such as a copying machine or an apparatus having an image reading function such as a flatbed type scanner (hereinafter referred to as an image reading apparatus), FIG.
As shown in FIG. 6, a transparent contact glass 1 is used as a document setting table. 5 and 6 show the contact glass 1 provided on the upper surface of the frame 2 of the image reading apparatus. The contact glass 1 is arranged so as to cover the opening 2a provided on the upper surface of the frame 2. Document guides (document scales) 3 and 4 are fixed along the left edge and the rear edge of the document, respectively, as abutment reference. These two document guides 3, 4
The intersections are arranged at right angles, and the operator sets the document by hitting the edges of the document against these document guides 3 and 4. The document guides 3, 4 have screw holes 3a, 4a as shown in FIG.
The screw 5 is fixed by screwing the screws 5 in such a manner that a is aligned with the corresponding screw holes on the upper surface of the frame. But,
If the screw 5 is simply fixed by screwing the screw 5 into the screw hole, the mounting position and the mounting position are determined by the dimensional difference between the inner diameter of the screw hole provided on each of the document guide and the frame and the outer diameter of the screw 5. There is a problem that variations occur in the state, and the two document guides 3 and 4 cannot be orthogonalized. Therefore, the frame side is provided with a protruding shape such as half-hollowed or embossed that can strictly control the external dimensions, and the document guide side is provided with a round hole or a long hole that fits this protruding shape. After positioning, a method of fixing with screw holes is adopted. When the document guide is made of resin, instead of providing a through hole such as the above-described positioning round hole or long hole, a blind-shaped recess is formed on the back of the document guide,
The holes and the protruding shapes unnecessary for the operator are concealed to prevent the appearance quality from deteriorating. On the other hand, when the original guide is made of sheet metal, the round holes and the long holes for positioning are naturally through holes, but when the original guide is fixed on the frame, the through holes and the protruding shape are exposed in appearance. Therefore, a method of covering this portion with an exterior cover is generally adopted.
Therefore, the operator can see only the screw holes and screws that are not covered by the outer cover. As described above, there is a requirement for the document guide to ensure the positional accuracy and appearance quality, and the document guide and the mounting structure as described above are employed to satisfy these requirements. However, it was necessary to rely solely on the intuition of the operator to line up the position of the document guide, which was a skilled work, and was considered to be a work with poor assemblability. In particular, in the market, service personnel have been working to reduce the time spent on maintenance as much as possible from the point of shortening machine downtime to increase operation rate and reducing service cost. There is a strong demand for improved assemblability.

[0003]

A problem to be solved by the present invention is to read a document guide (document scale) used as a document abutment reference in an image reading apparatus having a contact glass as a document setting table. An object of the present invention is to provide a document guide that can be easily and accurately fixed to a predetermined position on a housing at the time of assembling the apparatus, performing maintenance, or the like.

[0004]

In order to achieve the above object, the present invention is directed to a contact glass on which an original is placed, a frame having an opening for mounting the contact glass on an upper surface, and a contact glass. A scanner that scans to read an image of the original document, wherein the original guide is arranged along the edge of the contact glass as the original abutting reference, A narrow plate-like portion having a reference edge serving as a reference; and a mounting piece protruding from the other end of the narrow band-like portion, wherein the mounting piece has a screw hole and a U-shaped hole. And a tapered portion is formed, a screw hole matching the screw hole of the mounting piece, and a projection seated in the U-shaped hole are formed in a predetermined arrangement at an appropriate position on the periphery of the opening formed on the upper surface of the frame, Up The U-shaped hole has a seating portion for seating the protrusion at the back end, and the tapered portion communicates with the U-shaped hole, and the inner diameter gradually increases as the distance from the U-shaped hole increases. It is characterized by. The invention of claim 2 is
The document guide is made of sheet metal, and the tapered portion communicating with the U-shaped hole is formed as a hole penetrating a sheet metal constituting the document guide, or a cutout with one opening. According to a third aspect of the present invention, the document guide is made of resin, and instead of the U-shaped hole and the tapered portion, a U-shaped groove and a tapered groove are formed on the back surface of the document guide corresponding to these positions. It is characterized by.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings. FIGS. 1A, 1B, and 1C are a plan view, a rear view, and a right side view showing a document guide according to a first embodiment of the present invention. FIGS. It is a figure showing the procedure of attaching a guide to a frame (housing). The document guide 10 is fixed to the periphery of the opening provided on the upper surface of the frame of the image reading apparatus in the same manner as the document guides 3 and 4 shown in FIG. It is what is arranged. The document guide 10 includes a narrow plate-like portion 11 having a reference edge 11a serving as a document abutting reference, and at least two mounting pieces 12 protruding from the other end 11b of the narrow band-like portion 11. , Is provided. Further, as shown in FIG. 1 (c), the narrow plate portion 11 and the mounting piece 12 are connected not in a flat plate shape but in a stepped shape. The reference edge 11a is also connected to the narrow band-shaped portion main body in a stepped manner. Each of the mounting pieces 12 has a screw hole 13 and a U-shaped hole 14.
And a tapered portion 15 communicating with the U-shaped hole 14. An opening 2a formed on the upper surface of the frame 2 of the image reading device is provided at a proper position on the periphery thereof with a screw hole 1 of a mounting piece.
3 and a projection 21 fitted in the U-shaped hole 14 in an aligned state are formed in a predetermined arrangement. U
The character hole 14 is a through hole, but one end side has a tapered portion 1.
5 and has a cutout shape as a whole. The U-shaped hole 14 has a seating portion for positioning and seating the projection 21 at the back end, and one end of the U-shaped hole 14 is configured such that the distance between the inner walls gradually increases toward the outside. Is in communication with

The projection 21 is embossed with high processing accuracy, for example, and the projection 21 is seated in the U-shaped hole 14 to accurately position the document guide 10 with respect to the upper surface of the frame (for example, within an accuracy error of 0.1 mm or less). At). By maintaining the shape and positional accuracy of the U-shaped hole 14 and the projection 21 at a certain level or more, the positioning accuracy of the document guide 10 is increased.
The screwing using the screw 20 is merely an operation for fixing, and it is not necessary to secure the positional accuracy depending on the screwing.
This eliminates the problem that the positioning accuracy of the document guide is deteriorated due to an error between the inner diameter of the screw hole and the outer diameter of the screw. In addition, as the protrusion 21, other than embossing, a protrusion shape that can strictly control the external dimensions such as half-blanking can be adopted. When attaching the document guide 10 to the frame 2, the original guide 10 is initially inserted and slid in a rough sense so that the projection 21 is guided by the inner wall of the tapered portion 15 of the attachment piece 12, and finally the U-shaped hole 1 is inserted.
The projection 21 is tightly seated in 4. In this state, the positioning of the document guide 10 with respect to the frame has been completed.
Thereafter, the screw holes 13 and 20 are screwed into each other using the screw 22 to complete the fixing of the document guide. As shown in FIG. 5B, the document guide 10 is fixed by fixing the two screw holes 13 and 20 using the screw 22, and the outer cover 25 is put on the document guide 10 to complete the process. Only the part of the document guide 10 (the reference edge 11a on which the document size and the like are displayed) and the screw 22 are exposed and visible from the exterior cover 25, and the U-shaped hole 14, the tapered portion 15. The projection 21 is covered and concealed by the outer cover. As described above, according to the document cover and the structure on the frame side of this embodiment, when the mounting piece 12 is mounted on the frame side, rough positioning is performed so that the projection 21 enters the tapered portion 15 whose inner diameter gradually increases. Then, the document guide is slid so that the protrusion 21 is seated in the U-shaped hole 14,
The positioning is completed in this state. Therefore, the document guide 10 can be accurately fixed on the frame only by screwing the screw 22 into the screw hole. At this time, even if there is a slight dimensional error between the inner diameter of the screw hole and the outer diameter of the screw, since the positioning of the document guide 10 has already been performed by the U-shaped hole 14 and the projection 21, Character hole 14
As long as the screw is tightened while the projection 21 is seated at the back of the hole, accurate positioning can be performed without being affected by a slight displacement that may occur when the screw 22 between the U-shaped hole 14 and the projection 21 is tightened. Can be fixed. That is, according to this positioning and fixing method, the setability is remarkably improved as compared with the conventional method using a round hole and a long hole.

FIG. 3 is a perspective view showing a configuration of a document guide according to another embodiment of the present invention. The document guide 10 is made of sheet metal, and the other end of the narrow plate portion 11 is provided. 11b
Is a band-like body extending along the entire length of the other end edge 11b.
3, a U-shaped hole 14, and a tapered portion 15 communicating with the U-shaped hole 14. The feature of this embodiment is that the tapered portion 15 forms one through hole communicating with the U-shaped hole 14 instead of a notch whose one end is open.
When the original guide 10 of this embodiment is mounted on the upper surface of the frame 2, the screw holes 2 on the frame are also similar to the case of FIG.
0 and the projection 21 are used. That is, after the projection 21 is fitted into the tapered portion 15 as a through hole, the entire document guide is slid, and the projection 21 is seated in the U-shaped hole 14 to perform positioning. The screw 22 not shown in the screw holes 13 and 20 is maintained.
Is fixed by screwing the document guide. According to this positioning and fixing method, the setability is remarkably improved as compared with the conventional method using a round hole and a long hole.
Also, by attaching an exterior cover, the U-shaped hole 1
4. The tapered portion 15 is concealed. Next, FIG.
3A and 3B are a plan view and a bottom view showing a configuration example when a document guide is made of resin. When the document guide is made of a resin material, the U-shaped hole and the tapered portion can be formed not as through-holes but as grooves (concave portions) provided on the bottom surface. The appearance is improved. That is, the screw holes 13 as through holes are provided in the mounting pieces 12 connected to the narrow plate-like portion 11 in the same manner as in each of the above-described embodiments. Instead of the hole 14 and the tapered portion 15, a groove having the same function as these, that is, the U-shaped groove 1
4 ', a configuration in which a tapered groove 15' is provided on the bottom surface of the mounting piece 12 is characteristic. The configurations on the frame side corresponding to these are the same as those in the above embodiments, and the screw holes 20 and
Protrusions 21 such as embosses are formed in a positional relationship corresponding to the screw holes 13 and the U-shaped grooves 14, respectively. When attaching the document guide 10 to the upper surface of the frame, as in the above embodiments, the protrusion 21 is fitted into the tapered groove 15 ′ by rough positioning, and then the document guide is slid. Is seated in the U-shaped groove 14 '. While maintaining this state, screw holes 13, 2
By screwing and fixing the screw in 0, accurate mounting is completed. Further, since the U-shaped groove and the tapered groove do not appear on the surface of the document guide, the external appearance can be maintained without being concealed using an exterior cover. In any of the above embodiments, when the document guides on the left side and the back side shown in FIG.

[0008]

As described above, according to the present invention, a document guide (document scale) used as a document abutting reference in an image reading device having a contact glass as a document setting table is used when assembling the reading device. In addition, it is possible to provide a document guide that can be easily and accurately fixed to a predetermined position on a housing at the time of maintenance or the like. That is, according to the first aspect of the present invention, the document guide includes a narrow plate-shaped portion having a reference edge serving as a document abutting reference, a mounting piece protruding from the other end of the narrow band-shaped portion, A screw hole, a U-shaped hole and a tapered portion are formed in the mounting piece, and a screw hole matching the screw hole of the mounting piece is provided at an appropriate position around the opening formed in the upper surface of the frame; The protrusions seated in the holes are formed in a predetermined arrangement, and the tapered portion communicates with the U-shaped hole, and the inner diameter gradually increases as the distance from the U-shaped hole increases. After roughly fitting into the shape portion, the original guide is slid and the projection is seated in the U-shaped hole, thereby completing accurate positioning. Thereafter, screw fixing is performed using the screw hole while maintaining the positional relationship between the U-shaped hole and the projection, thereby completing the accurate fixing of the document guide. Next, in the invention according to claim 2, the document guide is made of sheet metal, and the tapered portion communicating with the U-shaped hole is formed as a hole penetrating the sheet metal constituting the document guide, or a notch having one open side. Therefore, it is suitable for roughly fitting the projection, and the workability is improved. In other words, even a low-skilled worker can perform accurate positioning and fixing work with sufficient probability. In the invention of claim 3,
Since the document guide is made of resin, and instead of the U-shaped hole and the tapered portion, a U-shaped groove and a tapered groove are formed on the back surface of the document guide corresponding to these positions,
The U-shaped groove and the tapered groove do not appear on the outer surface, so that it is not necessary to cover the groove with the outer cover.

[Brief description of the drawings]

FIGS. 1A, 1B, and 1C are a plan view, a rear view, and a right side view showing a document guide according to a first embodiment of the present invention.

FIGS. 2 (a) and (b) show a document guide in a frame (housing).
FIG.

FIG. 3 is a perspective view showing a configuration of a document guide according to another embodiment of the present invention.

FIGS. 4A and 4B are a plan view and a bottom view showing a configuration example when a document guide is made of resin.

FIG. 5 is an explanatory view of a state in which a conventional document guide is attached.

FIG. 6 is an explanatory diagram of a conventional document guide mounting procedure.

[Explanation of symbols]

10 Document Guide, 11 Narrow Plate, 11a Reference Edge, 11b Other Edge, 12 Mounting Piece, 13 Screw Hole,
14 U-shaped hole, 15 tapered shape part, 20 screw hole,
21 protrusion, 22 screw, 25 exterior cover.

Claims (3)

[Claims] 1. An image reading apparatus comprising: a contact glass on which an original is placed; a frame having an opening for mounting the contact glass on an upper surface; and a scanner for scanning an image of the original on the contact glass. A document guide mounted on the apparatus and arranged along the edge of the contact glass as a document abutting reference, wherein the document guide has a narrow plate-shaped portion having a reference edge serving as a document abutting reference, A mounting piece protruding from the other end edge of the narrow band-shaped portion, wherein the mounting piece has a screw hole, a U-shaped hole and a tapered portion, and an opening formed on the upper surface of the frame. A screw hole aligned with the screw hole of the mounting piece and a projection seated in the U-shaped hole are formed in a predetermined arrangement at an appropriate position on the peripheral edge, and the U-shaped hole is a seating portion for seating the projection at a rear end. Has, Serial tapered portion communicates with U-shaped holes, a document guide, characterized in that it is configured so as the inner diameter enough away from the U-shaped hole gradually increases. 2. The document guide according to claim 1, wherein the document guide is made of sheet metal.
2. The document guide according to claim 1, wherein the tapered portion communicating with the character hole is formed as a hole penetrating a sheet metal forming the document guide, or a notch having one open side. 3. The document guide is made of resin, and
2. The document guide according to claim 1, wherein a U-shaped groove and a tapered groove are formed on the back surface of the document guide corresponding to these positions instead of the character hole and the tapered portion.