JPS61158349A - Supporting device of traveling body - Google Patents

Abstract

PURPOSE:To travel a traveling body smoothly by forming at least two 1st bearings provided with V-shaped grooves abutted upon a guide shaft fixed on a traveling body and allowed to be slided on the guide shaft and 2nd bearings arranged on respective positions opposed to at least two 1st bearings through the guide shaft fixed on the traveling body. CONSTITUTION:The two 1st bearings 5a, 5b provided with respective V-shaped grooves abutted upon the guide shaft 3 are fixed. A plate spring 7 which is a pressing means is fixed on the lower part of the blacket part 1a of the 1st traveling body 1 through a screw 8 and rolls 9a, 9b which are the 2nd bearings are pivotally fitted to the projection part of the plate spring 7. The 1st bearings 5a, 5b are opposed to the rollers 9a, 9b through the guide shaft 3 and the rollers 9a, 9b press the guide shaft 3 with proper pressure by the spring force of the plate spring 7. Consequently, the traveling body 1 is held between the 1st bearing 5a and the roller 9a and between the other 1st bearing 5b and the other roller 9b. Namely, the traveling body is interposed at two points.

Description

TECHNICAL FIELD The present invention relates to a support device for supporting a traveling body moving along a guide shaft on the guide shaft.

BACKGROUND ART The above-described traveling body is used to move an exposure optical system for exposing and scanning a document in a document reading device attached to a printer or the like, or to similarly move an exposure optical system in a copying machine. Used in cases etc.

As a device for supporting this running body, as shown in the model in FIG.
5, these grooves are arranged so as to straddle the guide shaft 54, and the guide shaft 54 is received from below by a roller 56 attached to a bracket 55 extending downward from the traveling body 51.

In this device, by pulling the wire 57 in the A direction or the B direction, the traveling body 51 can be moved along the guide shaft 54 in the AA force direction or the BB force direction, respectively. As described above, the exposure optical system of the copying machine and the like are mounted on the traveling body 51. As a result, the traveling body 51 is supported at six points by the rollers 56 and the grooves 52 and 53.

This type of support device has a drawback in that when the wire 57 is pulled, a couple is generated on the traveling body 51, which causes the traveling body 51 to lift off from the guide shaft 54. for example,
When the wire 57 is pulled in the direction A, a force couple such as Ma is generated in the running body 51 that acts to press the groove 53 on the front side toward the guide shaft 54. When such a couple occurs, as shown in FIG. 6, a force pushing the groove 53 in the S direction acts, so that the slope on the right side of the groove 5 rides on the guide shaft 54 and moves north.
As a result, the traveling body 51 floats in the T direction, that is, upward in the figure.

When the traveling body is used for scanning a document by an exposure optical system, if the above-mentioned lifting occurs, it is inconvenient because the light image of the document image cannot be formed at an accurate imaging position.

OBJECTS In view of the above-mentioned points, an object of the present invention is to provide a support device for a traveling body that can prevent the traveling body from floating off the guide shaft and ensure smooth running of the traveling body.

Structure: The above purpose is to provide a support device for supporting a traveling body moving along a guide shaft on the guide shaft, which is provided with a V-shaped groove that is fixed to the traveling body and comes into contact with the guide shaft, and is capable of sliding on the guide shaft. This is achieved by providing at least two first bearings and a second bearing fixed to the traveling body and disposed at a position facing each of the at least two first bearings with the guide shaft in between.

Hereinafter, the present invention will be explained in detail using drawings showing embodiments thereof.

FIG. 1 is a side sectional view of an example of a document reading device using a support device for a traveling body according to the present invention. In this device, an original 51 placed on an original platen 50 made of glass is illuminated by a lamp 52, and the reflected image light is transmitted to the first mirror 5, the second mirror 54, the fifth mirror 55, and the like. lens 56
The image is projected onto a line sensor 57 via the line sensor 57, and the original image is read by the line sensor 57. The line sensor 57 is composed of a so-called CCD or the like.

When reading the original 51, the lamp 52 and the first mirror 5
5 moves as one in the direction of arrow F from the position indicated by the solid line in the figure. At that time, the second mirror 54 and the fifth mirror 55 similarly move together in the direction of arrow F. However, the second
The moving speed of the mirror 54 and the sixth mirror 55 is determined by the ramp 52.
and half the moving speed of the first mirror 5. Therefore,
The final positions of the lamp 52 and each of the mirrors 53 to 55 are as shown in the broken columns in the figure.

The document 51 is sub-scanned by the movement of the lamp 52 and the mirrors 56 to 55 in the F direction, and the document 51 is main-scanned by the self-scanning of the line sensor 57, so that the image of the document 51 is read two-dimensionally by the line sensor 57. hand,
converted into an electrical signal.

In this way, the lamp 52 and the mirrors 56 to 55 are connected to the original 5.
It moves for sub-scanning in step 1, but the movement is
Regarding the lamp 52 and the first mirror 53, the first mirror in FIG.
The sixth mirror 54 and the fourth mirror 55 are provided by the second traveling body 2 in FIG. 2.

As mentioned above, since the lamp 52 and the first mirror 5 move at twice the speed of the second mirror 54 and the sixth mirror 55, the first traveling body 1 is faster than the second traveling body 2. Therefore, the first traveling body 1 moves inside the second traveling body 2 relative to the second traveling body 2. Note that the direction of arrow F in FIG. 2 is the same as the direction indicated by the same reference numeral in FIG.

Both the first traveling body 1 and the second traveling body 2 are equipped with support devices that are embodiments of the present invention, but they are not the same embodiment and are different from each other.

Each of these embodiments will be individually described below.

First, as shown in FIG. 3, which is a sectional view taken along line I[l-111 in the figure, the first traveling body 1 has two grooves each having a V-shaped groove 4 that abuts on the guide shaft 5. 1 bearings 5a and 5b are fixed. Reference numeral 6 indicates a screw that fixes the first bearings 5a, 5b to the first traveling body 1.

The distance between both bearings 5a and 5b is set to an appropriate value t1. Hereinafter, tl will be referred to as the distance between bearings.

In FIG. 2, a bracket portion 1a extending downward is formed approximately in the center of the first traveling body 1, and a plate 7 serving as a pressing means is provided at the bottom of the bracket portion 1a.
are fixed by screws 8. The leaf spring 7 has protrusions 7a and 7b at positions separated from each other by a distance approximately equal to the inter-bearing distance t1 with the bracket part 1a at the center, and these protrusions have rollers 9a as a second bearing. , 9b
is rotatably attached.

The first bearings 5a, 5b and the rollers 9a, 9b are located opposite each other with the guide shaft 5 in between, and the rollers 9a, 9b press the guide shaft roller with appropriate pressure by the spring force of the leaf spring 7. As a result, the traveling body 1 is held between the first bearing 5a and the rollers 9a, and further between the other first bearing 5b and another roller 9b. That is, it is held between two points.

Since the first traveling body 1 is supported with the guide shaft 5 sandwiched between the two sets of bearings facing each other in this way,
As explained in relation to FIGS. 5 and 6, even if a couple occurs in the first traveling body 1 while it is running, the rollers 9a, 9b
The pressing force prevents the first traveling body 1 from lifting off from the guide shaft 5, thereby ensuring smooth running of the first traveling body 1.

The spring force of the leaf spring 7 is not increased more than necessary.

This is because if the spring force is too large, running resistance when moving the first running body 1 in the F direction will increase. Specifically, the spring force may be set such that it can prevent the first traveling body 1 from lifting up when the largest couple (Ma; FIG. 5) that can be considered in the design is applied.

The above is the first embodiment of the present invention applied to the first traveling body 1. Next, a second embodiment of the present invention applied to the second traveling body 2 will be described. In FIG. 2, the second traveling body 2 is provided with two first bearings 15a and 15b separated by a distance t2 that is longer than the inter-bearing distance t1 of the first traveling body 1.

As shown in FIG. 4, the fact that the first bearing 15b (15a) has a V-shaped groove 14 that contacts the guide shaft 3 and that it is fixed to the second traveling body 2 by a screw O is the same as in the first embodiment. It's no different than the case. The difference from the first embodiment is that the first
A second bearing disposed opposite the bearings 15a and 15b,
The point is that it is configured not as rollers but as sliding bearings 19a and 19b.

Even when the second bearings are sliding bearings 19a and 19b, when a couple (FIG. 5) occurs in the second traveling body 2 and the second traveling body 2 tries to lift off from the guide shaft 5, the sliding Bearing 19
a and 19b collide with the guide shaft 3 and are prevented from floating.

Note that if the sliding bearings 19a and 19b are in close contact with the guide shaft 5, the running resistance of the second running body 2 will increase and the running will not be carried out smoothly, so there is an appropriate vaginal space between them. This is desirable. However, if the gap is too large, the intended purpose of preventing the second traveling body 2 from floating up cannot be achieved. Experimentally, a value of about 0.02 to 0.05 m5 was found to be good.

Two embodiments have been described above, and each of these embodiments has its own unique features. First, the first embodiment attached to the first traveling body 1 is particularly effective when the distance t1 between bearings is short. Generally, the lifting of the traveling body is inversely proportional to the distance between bearings (for example, 11 in FIG. 1). That is,
The shorter the distance between the bearings, the more likely it is that lifting will occur, and the amount of lifting will also be larger. Therefore, in order to reliably prevent floating, the gap between the second bearing (for example, 9a, 9b in FIG. 2) and the guide shaft should be as small as possible, and preferably, they should be in contact with each other. Here, if sliding bearings 19a and 19b as in the second embodiment are used as the second bearings,
As mentioned above, running resistance increases, making it impractical. On the other hand, as in the first embodiment, the rollers 9a as the second bearing,
By using 9b, it is possible to keep the running resistance low and also to reliably prevent the running body from lifting up.

The second embodiment attached to the second traveling body 2 is particularly effective when the bearing amount distance t2 is long, and has the advantage of being low in cost. As is clear from the above description, in general, when the distance between the bearings (for example, t2 in FIG. 2) is long, lifting is less likely to occur and the amount of lifting is small. Therefore, in this case, there may be no practical problem even if the second bearing (for example, 19a, 19b in FIG. 2) and the guide shaft do not necessarily come into contact with each other. In this case, using a roller as the second bearing as in the first embodiment and further providing a leaf spring 7 to press the roller against the guide shaft would be expensive and impractical.

In addition, in the above explanation, the angles θ1 and θ of the V-shaped groove 4 (FIG. 5) of the first embodiment and the V-shaped groove 14 (FIG. 4) of the second embodiment are
2 was not specifically mentioned, but the distance t1 between the bearings in the first embodiment is shorter than the distance L2 between the bearings in the second embodiment.
In the case of the illustrated embodiment, the groove angle θ1 in the first embodiment is
It is desirable that the groove angle θ2 be smaller than the groove angle θ2 in the second embodiment. In the embodiment, θ1=60' and θ2=90°.

The reason is as follows. As can be understood from FIG. 6, when the angle of the V-shaped groove is small, even if a couple is generated on the traveling body 51 in FIG. 5, the slope of the V-shaped groove 53 is difficult to climb onto the guide shaft 54. Therefore, floating of the traveling body is less likely to occur. Therefore, it is more convenient to reduce the groove angle θ1 in the first embodiment, where the distance between the bearings is short and lifting is likely to occur, in order to prevent the traveling body from lifting.

However, reducing the groove angle θ1 or θ2 of the first bearing is difficult to process, and it is difficult to achieve dimensional accuracy in the height direction of the traveling body 1 or 2 (vertical direction in FIGS. 2 to 4). Therefore, it is better to avoid making the groove angle of the first bearing smaller than necessary.

As described above, the groove angle θ of the first bearings 5a, 5b or 15a, 15b is determined depending on the length of the first bearing distance t1 or t2.
By changing the magnitude of 1 or θ2, an appropriate effect of preventing the traveling body from floating can be obtained depending on each case. Apart from this, if the values of the groove angles θ1 and 02 are made different, the first bearings 5a and 5b in the first embodiment are in contact with the guide shaft 6 at 1EtP (FIG. 5) and the second embodiment is The IQ (FIG. 4) at which the first bearings 15a and 15b contact the guide shaft 6 are different from each other. This means that the first bearing 5 according to the first embodiment
a, 5b and the first bearing 15a according to the second embodiment.

15b slide at the same time, the respective sliding trajectories will be at different positions on the guide shaft 3, and as a result, the two first bearings will slide on the guide shaft drawing the same trajectory. Compared to the case, the wear of the guide shaft is reduced,
This has the effect of extending the lifespan.

Note that in FIGS. 1 and 2, the distance between the bearings lit t 1 of the first bearings 5a and 5b that support the first traveling body carrying the lamp 52 and the first mirror 53, which have a long running distance, is shortened ( Embodiment 1) On the other hand, the first bearing 15a supports the second traveling body carrying the second mirror 54 and the sixth mirror 55, which have a short traveling distance.

The reason why the distance tz between the bearings 15b is made longer (in the second embodiment) is to make the overall width W of the device as short as possible with respect to the length of the document 51 in the sub-scanning direction in FIG. It is. Therefore, if there is no such restriction on the overall width W of the device, the support device for the first traveling body that supports the lamp 52 and the first mirror 56 may be a second embodiment in which the distance between the bearings is long.

In this case, even if the distances between the bearings of the supporting devices of both traveling bodies are made equal, it is desirable that the angles of the V-shaped grooves in the surface supporting devices are set to different values in advance. As mentioned above, this is to extend the life of the guide shaft 6.

Effects According to the present invention, the traveling body moving along the guide shaft can be prevented from floating off the guide shaft, and the traveling body can run smoothly.

[Brief explanation of the drawing]

1 is a side sectional view of a document reading device to which the present invention is applied, FIG. 2 is a side view showing two different embodiments of the present invention, and FIG. 3 is a side view taken along the lll-In line in FIG. Figure 4 is a cross-sectional view taken along the line ■-■ in Figure 2;
FIG. 5 is a perspective view of an example of a conventional support device for a traveling body, and FIG. 6 is a sectional view taken along v+-v+i in FIG. 6... Guide shaft 1, 2... Traveling body 4114
...V-shaped grooves 5a, 5b, 15a, 15b-first bearing 9a,
9b, 19a, 19b - 2nd bearing 1 so 0

Claims (3)

[Claims] (1) In a support device that supports a traveling body moving along a guide shaft on the guide shaft, at least two devices are fixed to the traveling body and have a V-shaped groove that abuts the guide shaft, and are slidable on the guide shaft. A support device for a traveling body, comprising a first bearing and a second bearing fixed to the traveling body and disposed at a position facing each of the at least two first bearings with a guide shaft in between. (2) The supporting device for a traveling body according to claim 4, wherein the second bearing is a sliding bearing disposed with a slight gap from the guide shaft. (3) The traveling body according to claim 1, wherein the second bearing is a roller that contacts the guide shaft, and the roller is further pressed against the guide shaft by a pressing means. Support device.