JPH08234321A - Guide mechanism for moving body of original scanning device - Google Patents

Abstract

PURPOSE: To sufficiently suppress the oscillation or velocity unevenness of the moving body (slider) of a single-side driving type original scanning device and improve the quality of a read image. CONSTITUTION: In the guide mechanism for the slider 1 of the device for moving the slider 1 by the guide of a guide shaft 2 inserted through the bearing 4 of the slider 1 loading with an optical member to scan an original by the optical member, at least three nonelastic projection parts 41a, 41b, 41c are provided on the bearing 4 in such a manner that the top ends of the projection parts 41a, 41b, 41c are situated within the same plane including the shaft center of the guide shaft 2, and the top end of each projection part 41a, 41b, 41c situated within the same plane comes into contact with the circumferential surface of the guide shaft 2 so as to nip the guide shaft 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a guide mechanism for a moving body (a member for mounting an optical member = a slider) of a document scanning device such as a copying machine or an image scanner.

[0002]

2. Description of the Related Art A copying machine or the like is provided with a document scanning device for exposing and scanning a document image on a platen glass in a slit shape and focusing the reflected light on the surface of a photoconductor.
This scanning device generally comprises two lasers arranged in parallel.
And a first moving body and a second moving body that reciprocate (slide) on the two rails guided by a guide. The guide may be shared with any one rail. An exposure lamp and a first reflecting mirror are mounted on the first moving body, and a second reflecting mirror and a third reflecting mirror are mounted on the second moving body. The reciprocating movement of the first and second moving bodies is performed by pulling both ends or one end of the first moving body in the positive direction along the guides during scanning (forward movement), and at the time of returning (returning movement). It is realized by pulling both ends or one end of the two moving bodies in the opposite direction along the guide. The case of pulling both ends is called the double-sided drive system, and the case of pulling one end is called the single-sided drive system. The one-sided drive method is effective in reducing the number of parts and downsizing the device because the mechanism for transmitting the driving force from the motor to the moving body can be simplified.
The towed portion of the second moving body is a moving pulley, and since the moving end side of the wire of this moving pulley is fixed to the towed portion of the first moving body, the moving speed of the second moving body is the same as that of the first moving body. Moving speed 1
/ 2.

Japanese Unexamined Patent Publication No. 5-303147 discloses an optical unit (original scanning device) having two rails and one guide shaft, and a guided portion (bearing) on the reading unit (moving body) side. ), The guide shaft is elastically sandwiched between two sliding members facing each other in the bearing, and the pressing force can be adjusted. This device eliminates rattling of the guide shaft and bearing by adjusting the pressing force applied to the sliding material, and optimizes the load during movement, thereby suppressing the shaking of the moving body and blurring during document reading. Is being reduced.

In Japanese Unexamined Patent Publication No. 58-24166, the ends of the wires for pulling the moving body are attached to positions on opposite sides of the guide shaft at both ends in the moving direction of the moving body. A document scanning device is disclosed in which a moment force is applied from the inner surface to a guide shaft.
In this device, the moment force stabilizes the frictional load between the bearing and the guide shaft to suppress the shaking of the moving body and reduce the blurring during the reading of the document.

[0005]

In the document scanning device, when the moving body carrying the optical member is moved, the image quality of the read image is deteriorated when the head swings or the speed is uneven. For this reason,
JP-A-5-303147 and JP-A-58-2416
Although the measures of Japanese Patent No. 6 have been taken, in these devices, it is difficult to adjust the clearance because the inner surface of the bearing and the peripheral surface of the guide shaft are in surface contact, and as shown in FIG. The contact position tends to fluctuate, and it becomes insufficient to suppress swinging and uneven speed. In FIG. 3B, 2 is a guide shaft and 400 is a bearing of the moving body. SUMMARY OF THE INVENTION It is an object of the present invention to improve the quality of a read image by sufficiently suppressing swinging of the moving body of the document scanning device, speed unevenness, and the like.

The above-mentioned one-sided drive system is effective in reducing the number of parts and downsizing of the apparatus, and is a promising system. However, since it is a structure in which only one side of the moving body is towed, swinging, speed fluctuation, etc. However, there is a problem that it becomes larger than the double-sided drive system. An object of the present invention is to suppress swinging of the moving body (slider), fluctuations in speed, etc., to the extent that it can be sufficiently used in a single-sided drive system.

[0007]

The present invention is a mechanism in which an inner surface of a bearing and a peripheral surface of a guide shaft are inelastic point-contact with each other in the same plane including a guide shaft core. That is, a guide mechanism for a moving body of an apparatus that moves the moving body by guiding a columnar guide shaft inserted into a bearing hole of a moving body (slider) on which an optical member is mounted and scans a document by the optical member. The tips of at least three inelastic projections are located in the same plane including the axis of the guide shaft, and the tips of the projections located in the same plane are in contact with the guide shaft to sandwich the guide shaft. The guide mechanism for the moving body of the document scanning device, wherein each of the protrusions is provided in the bearing hole.

Further, the present invention is a mechanism in which the inner surface of the bearing and the peripheral surface of the guide shaft are inelastically in line contact in the guide shaft direction. That is, a guide mechanism for a moving body of an apparatus that moves the moving body by guiding a columnar guide shaft inserted into a bearing hole of a moving body (slider) on which an optical member is mounted and scans a document by the optical member. Movement of a document scanning device provided with two inelastic flat portions in the bearing hole so that a plane including the axis of the guide shaft contacts the guide shaft on a line intersecting the peripheral surface of the guide shaft. It is a body guiding mechanism.

Further, the present invention is a mechanism in which the inner surface of the bearing and the peripheral surface of the guide shaft are elastically brought into point contact in two planes orthogonal to the guide shaft. That is, a guide mechanism for a moving body of an apparatus that moves the moving body by guiding a columnar guide shaft inserted into a bearing hole of a moving body (slider) on which an optical member is mounted and scans a document by the optical member. A guide mechanism for a moving body of a document scanning device, which is provided with two ring-shaped portions, which are in contact with the peripheral surface of the guide shaft and have at least three elastic protrusions sandwiching the guide shaft, in the guide shaft direction in the bearing hole. Is.

[0010]

In the invention in which the inner surface of the bearing and the peripheral surface of the guide shaft inelastically make point contact or line contact in the same plane including the guide shaft core, there is no fluctuation in the contact area as in the case of surface contact, and contact does not occur. Positional variation is small. In the invention in which the bearing inner surface and the guide shaft peripheral surface are elastically in point contact with each other in two planes orthogonal to the guide shaft, the contact area and contact position vary less than in the case of surface contact.

[0011]

【Example】

First Embodiment (corresponding to claim 1) FIG. 1 shows a first embodiment, (a) is a schematic top view,
(B) is a schematic vertical sectional view, (c) is a protrusion in the bearing 4
FIG. 41 is a schematic perspective view of 41c (41a, 41b). In the first embodiment, the slider (moving body) 1 is moved by the pulling force of the wire 3 to the rail.
5 along with guide axis 2
1 is a guide mechanism of an apparatus for scanning an original document on an original platen glass (not shown) by an optical member (not shown) mounted on 1.

One end of the slider 1 is movably supported on a rail 5 via a rolling wheel 6, and the other end of the slider 1 is a bearing 4
It is slidably supported by the guide shaft 2 via. The guide shaft 2 has a circular cross section, and the bearing 4
The tips of the non-elastic projections 41a, 41b, 41c formed on the inner surface of the abutting portion abut. The protrusion 41a is the front end of the bearing 4 (see FIG. 1).
Is formed on the inner side (right side in FIG. 1A) sandwiching the guide shaft 2 in (a) above, and the projection 41b is formed inside the rear end. In addition, the protrusion 41c is
It is formed on the outer side with the guide shaft 2 sandwiched between a and the protrusion 41b. Therefore, the guide shaft 2 comes into contact with the tips of the protrusions 41a and 41b from the inside and the protrusion 41c from the outside.
Will be brought into contact with the tip of the. Each protrusion 41a, 41b, 41c
1 has a substantially semi-elliptical columnar shape as shown in FIG. 1 (c), and this semi-elliptic column is vertically oriented in the bearing 4 (direction perpendicular to the paper surface of FIG. 1 (a)). It is provided. In addition,
In the figure, reference numeral 42 is a support plate which is projected from the bearing 4 to the wire side, and 42a is a locking plate for locking the wire 3 to the support plate 42. Further, the tips of the protrusions 41a, 41b, 41c are herein the peak positions of the semi-ellipse.

Thus, the other end side of the slider 1 is
Since the tips of the protrusions 41a, 41b, 41c in the bearing 4 are inelastically contacted with the guide shaft 2 to make point contact with the guide shaft 2, the clearance with the guide shaft 2 can be minimized. Unlike the conventional case, it is possible to eliminate a problem such as horizontal swinging due to a change in the contact area. The other end of the slider 1 in the vertical direction may be regulated by supporting the upper inner surface of the bearing 4 by the upper peripheral surface of the guide shaft 2, as in the third embodiment described later. A guide rail 50 may be provided and supported.

Further, the protrusions 41a, 41b, 41 of the first embodiment
The optimum position of c is given as shown in FIG.
That is, a, b, and c are the positions of the protrusions 41a, 41b, and 41c,
Let lac be the distance between the protrusions 41a and 41c, lcb be the distance between the protrusions 41c and 41b, Wa be the front bearing load, and Wb be the rear bearing load.

[Equation 1] By setting as Wa · lac = Wb · lcb, the effect of the present invention can be optimally achieved.

Second Embodiment (corresponding to claim 1) FIG. 2 shows a second embodiment, (a) is a schematic top view,
(B) is a schematic vertical sectional view, (c) is a protrusion in the bearing 4
FIG. 4 is a schematic perspective view of 410c (410a, 410b). The second embodiment, like the first embodiment, has a slider (moving body).
A guide mechanism of a device that scans a document on a platen glass (not shown) with an optical member (not shown) mounted on the slider 1 by moving 1 along the rail 5 and the guide shaft 2 by the pulling force of the wire 3. Is. Hereinafter, differences from the first embodiment will be mainly described, and description of the same points as the first embodiment will be omitted. The same members as those in the first embodiment are designated by the same reference numerals as those in the first embodiment.

In the second embodiment, each of the projections 410a, 410b, 410c whose tip is inelastically brought into contact with the guide shaft 2 has a semi-elliptic cylindrical shape as shown in FIG. 2 (c). The members have a combined shape in an orthogonal state, and these members are provided at the same positions as the protrusions 41a, 41b, 41c of the first embodiment. The protrusion 410c provided in the middle part is provided so that the portion protruding laterally is at the lower position.
Protrusions 410a, 410b provided on the front and rear ends of the bearing 4
Is provided so that the laterally protruding portion is located at the upper position. For this reason, the guide shaft 2 is
The left and right directions are sandwiched and regulated by b and 410c, and the up and down directions are also sandwiched and regulated. Therefore,
In the second embodiment, unlike the first embodiment, it is not necessary to regulate the vertical direction by another member. In addition,
The optimum positions of the respective protrusions 410a, 410b, 410c of the second embodiment are given in FIG. 3 (a) as in the first embodiment.

Third Embodiment (Corresponding to Claim 2) FIG. 4 shows a third embodiment, (a) is a perspective view and (b) is a schematic vertical sectional view. In the third embodiment, a bearing plate (inelastic flat portion) 411 is provided on the inner side surface of the bearing 4, and the bearing plate 411 and the peripheral surface of the guide shaft 2 are in line contact with each other. That is, the surface of the bearing plate 411 linearly contacts the peripheral surface of the guide shaft 2 at the portion where the virtual plane including the axis of the guide shaft 2 intersects the peripheral surface of the guide shaft 2. Therefore, in the third embodiment, the clearance with the guide shaft 2 can be minimized as in the first and second embodiments, and the problems such as horizontal swinging due to the variation of the contact area can be solved. can do. In the third embodiment, the slider
One end of 1 is slidably supported on the rail 5 via a bush 61, and the other end is rail-mounted via a bush 62.
It is slidably supported on 50. That is, in the third embodiment, both ends of the slider 1 are supported by the rails 5 and 50, and the guide shaft 2 is used exclusively for guiding the slider 1. The third embodiment configured in this way has the advantages that the number of parts is small and the assembly and adjustment are easy, as compared with the first and second embodiments.

Fourth Embodiment (corresponding to claim 3) FIG. 5 shows a fifth embodiment, (a) is a schematic top view,
(B) and (c) are schematic cross-sectional views of ring-shaped portions formed at both ends of the bearings 4, 40. In the fifth embodiment, the slider 1
An elastic ring portion 45a is formed inside the front end of the bearing 4 of
An elastic ring-shaped portion 45b is formed inside the rear end portion. As shown in FIGS. 5 (b) and 5 (c), each of the ring-shaped portions 45a, 45a has its tip abutted against the peripheral surface of the guide shaft 2 in an imaginary plane orthogonal to the axis of the guide shaft 2 so that the guide shaft is It has 3 protrusions that regulate 2 In other words, in the third embodiment, the bearing 4
The guide shaft 2 is elastically regulated by the three protrusions of the ring-shaped portions 45a and 45b formed at both ends of the guide shaft 2, respectively. Therefore, the clearance with the guide shaft 2 can be minimized, and horizontal swing or the like due to the change in the contact area can be eliminated. Note that (b) shows the case where the protrusion is formed separately from the bearing 4, and (c) shows the case where the protrusion is formed integrally with the bearing 4. Guide shaft in the fourth embodiment
Since the contact with 2 is elastic, high precision of parts as in the first to third embodiments is not required. Further, since the point contact is elastic, problems such as swinging can be favorably solved even without any adjusting mechanism.

In FIG. 5, reference numeral 10 designates a second slider, and the second slider 10 is provided with a second reflecting mirror and a third reflecting mirror (not shown) as described in the section of the prior art. ing. The first slider 1 is provided with an exposure lamp and a first reflecting mirror, which are not shown, as described in the section of the prior art. In the first to third embodiments, only the first slider 1 will be described, and the description of the second slider will be omitted. The second slider 10 has one end movably supported by the rail 5 via the rolling wheels 60 and the other end supported by the bearing 40.
It is slidably supported by the guide 2 via. In addition,
At both ends of bearing 40, ring-shaped parts 405a, 405b similar to bearing 4
Is formed and regulates the guide shaft 2 as in the case of the bearing 4.

[0020]

According to the invention in which the inner surface of the bearing and the peripheral surface of the guide shaft inelastically make point contact or line contact in the same plane including the guide shaft core, there is no change in the contact area and there is little change in the contact position. Therefore, problems such as swinging of the moving body and speed fluctuations can be sufficiently suppressed. As a result, it is possible to obtain a read image with good image quality even in the case of the one-side drive system. Further, it is not necessary to adjust the clearance or to have high processing accuracy. In the invention in which the inner surface of the bearing and the peripheral surface of the guide shaft elastically make point contact in two planes orthogonal to the guide shaft, the contact area and the contact position vary little, so that the swinging of the moving body, the speed variation, etc. It is possible to sufficiently suppress defects. As a result, it is possible to obtain a read image with good image quality even in the case of the one-side drive system. Also,
There is no need for clearance adjustment or high processing accuracy.

[Brief description of drawings]

FIG. 1 is a top view (a) and a vertical cross-sectional view (b) schematically showing the guide mechanism of the first embodiment, and a schematic perspective view (c) showing a protrusion in a bearing of the guide mechanism.

FIG. 2 is a top view (a) and a vertical cross-sectional view (b) schematically showing a guide mechanism of the second embodiment, and a schematic perspective view (c) showing a protrusion in a bearing of the guide mechanism.

FIG. 3 is an explanatory view (a) showing dimensional ratios of respective portions of the first and second embodiments and an explanatory view (b) showing problems of the conventional guide mechanism.

FIG. 4 is a perspective view (a) showing a guide mechanism of the third embodiment,
Schematic longitudinal sectional view (b).

FIG. 5 is a top view (a) schematically showing the guide mechanism of the fourth embodiment, and schematic sectional views (b) (c) showing the inside of the bearing of the guide mechanism.

[Explanation of symbols]

 1, 10 moving body 2 columnar guide 3 wire 4, 40, 400 bearings 41a, 41b, 41c, projections 410a, 410b, 410c projections 411 bearing plate (inelastic flat surface) 45a, 45b, 405a, 405b ring-shaped section 5 , 50 rails

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Masanori Murakami Inventor Masanori Azuchi 2-3-3, Azuchi-cho, Osaka City Osaka Kokusai Building Minolta Co., Ltd. (72) Inventor Hiroshi Nishiki 2-chome Azuchi-cho, Chuo-ku, Osaka No. 13 Osaka International Building Minolta Co., Ltd.

Claims (3)

[Claims] 1. A guide mechanism for a movable body of a document scanning device, wherein the movable body is moved by a guide of a columnar guide shaft inserted into a bearing hole of a movable body on which an optical member is mounted, and a document is scanned by the optical member. The tips of at least three inelastic protrusions are located in the same plane including the axis of the guide shaft, and the tips of the protrusions located in the same plane are in contact with the guide shaft. A guide mechanism for a moving body of a document scanning device, wherein each of the protrusions is provided in the bearing hole so as to sandwich the guide shaft. 2. A guide mechanism for the moving body of a document scanning device, wherein the moving body is moved by the guide of a columnar guide shaft inserted into a bearing hole of the moving body on which the optical member is mounted, and the document is scanned by the optical member. An original document, wherein two inelastic flat portions are provided in the bearing hole so that a plane including the axis of the guide shaft abuts the guide shaft on a line intersecting the peripheral surface of the guide shaft. A guide mechanism for the moving body of the scanning device. 3. A guide mechanism for the moving body of a document scanning device, wherein the moving body is moved by the guide of a columnar guide shaft inserted into a bearing hole of the moving body on which the optical member is mounted, and the document is scanned by the optical member. The document scanning device is provided with two ring-shaped portions, which are in contact with the circumferential surface of the guide shaft and have at least three elastic protrusions sandwiching the guide shaft, in the bearing shaft direction in the bearing hole. Body guidance mechanism.