JPH0289466A - image reading device - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] "Industrial application field" The present invention relates to the configuration of an image reading device.

1. Prior Art 1 A typical document reading device for inputting documents such as text and photographs into a computer is called a flatbed image scanner.

This generally has an optical head that reads one line of a document and a mechanism that moves the optical head in a direction perpendicular to the reading line, and the optical head reads the entire document while moving along the document. FIG. 4 shows a perspective view of an example of the basic configuration of a flatbed type image scanner. FIG. 5 shows an example of an optical head. In FIG. 5, the original 11 placed on the glass stand is illuminated by illumination devices 12-G and 1.
2-B and 12-R, and the image is captured by the imaging system 15.
An image is formed on the sensor 16 by. Although a cross section is shown here, in reality, the lighting devices 12-G, 12-B, 1
2-R has a length in the front depth direction of the page, and sensor 1
6 are also arranged one-dimensionally in the same direction. That is, in the scanner according to the configuration example shown in FIG. 4, the optical head 1 has a configuration as shown in FIG. That's why I'm going.

FIG. 6 is a diagram showing an example of a conventional configuration of a flatbed type image scanner. In this example, a cylindrical metal guide shaft 19 is used as a guide for moving the optical head configured as shown in FIG. 5 along the document surface. A planar guide rail 18 is arranged to restrict rotation. Therefore, when the optical held 17 scans the document surface, the guide shaft 19 regulates both the distance between the document surface and the optical held 17 and the direction horizontal to the document surface.
The other side has a structure in which a guide rail 18 regulates the distance from the document surface.

[Problems and objects to be solved by the invention] However, in the configuration of a conventional scanner, there is a guide shaft 19 that regulates the moving direction of the optical radar 17, and a guide shaft 19 that regulates the moving direction of the optical radar 17.
A gap must be provided between the cylindrical bearing 20 and the sliding cylindrical bearing 20 to absorb component tolerances and thermal expansion.

Therefore, when the optical head 17 scans, the optical head shakes, causing a problem that the read image becomes blurred.

In view of the above drawbacks, the present invention aims to realize a structure that does not generate vibrations when scanning an optical head with an inexpensive configuration.

[Means for Solving the Problems] As a means for solving the problem, in the present invention, as a guide member for regulating the scanning direction of the imaging system, a member for regulating the distance between the sensor and the document surface and a member arranged in the same manner as the sensor arrangement are used. The present invention is characterized in that it has a separate member that regulates the same direction as the sensor array, and has a mechanism that presses the sliding member against the member that regulates the same direction as the arrangement of the sensors.

Furthermore, in the above configuration, the part that regulates the distance to the document surface and the part that regulates the same direction as the sensor arrangement are constructed as an integral member, and a guide member is further provided to regulate the scanning direction of the imaging system. It is characterized by being constructed from extruded material such as aluminum.

[Example] FIG. 1 shows an example of the present invention. In this example, sliding chips 5 are fixed to both ends of the optical head 1, and the distance between the head and the document surface is kept constant by sliding on the sliding rail A3. Further, the carriage 2 fixed to the lower part of the optical head 1 has a configuration as shown in FIG.
It is rotatably attached to a shaft planted in the

Therefore, the sliding rail B4 moves to the roller AI due to the force of the leaf spring.
It is sandwiched between O and roller B8.

With such a configuration, the optical head 1 can slide in the direction of the arrow in the figure without causing rattling.

FIG. 3 shows a second embodiment of the invention. In this example, by integrating the sliding rail section A and the sliding rail section 8, the positional accuracy between the rails can be improved.

In addition, in the configuration example shown in FIGS. 1 and 3, since the shape of the slide rail can be configured to have the same cross section in the sliding direction of the optical head 1, it is possible to configure the slide rail with the same cross section in the sliding direction of the optical head 1. This further improves positional accuracy.

[Effects of the Invention] According to the present invention, in an image reading device that reads a document by moving an optical head, it is possible to slide the optical head without causing any play in the optical head. In addition, since the shape and structure are simpler than conventional techniques, the sliding rail itself can also serve as the main body frame, reducing costs and improving accuracy.

Furthermore, in the actual example, aluminum A6063 for extrusion molding was used in the configuration shown in FIG. It has been confirmed that in combination with a dynamic tip, very good sliding and wear characteristics can be obtained in practice.

[Brief explanation of the drawing]

FIG. 1 is a main sectional view showing an embodiment of an image reading device of the present invention. FIG. 2 is a partial explanatory diagram of the embodiment shown in FIG. FIG. 3 is a diagram showing another specific example of the present invention. FIG. 4 is a perspective view of a configuration example of a flatbed type image scanner. FIG. 5 is a diagram showing an example of the configuration of an optical head. FIG. 6 is a sectional view showing an example of a conventional configuration. 1: To optics・2 do 5: Sliding chip 2 Figure 8: Roller A 9: Leaf spring 10: Roller B Applicant Seiko Epson Co., Ltd. Agent Patent attorney Kizobe Suzuki and 1 other person 7: Koko head Figure 3 Figure 4 Figure 7: Tokohe Rad Figure 5

Claims (3)

[Claims] (1) In an image reading device equipped with an optical one-dimensional sensor for reading an image on the document surface and a mechanism that scans part or all of the imaging system in a direction perpendicular to the array of the sensor, As a guide member for regulating the scanning direction of the image system, a member for regulating the distance between the sensor and the document surface and a member for regulating the same direction as the sensor arrangement are separately provided, and An image reading device characterized by having a mechanism for pressing a sliding member against a member regulating the same direction. (2) The image reading device according to claim 1, characterized in that the part that regulates the distance to the document surface and the part that regulates the same direction as the arrangement of the sensors are constructed as an integral member. (3) The image reading device according to claim 1, wherein the guide member for regulating the scanning direction of the imaging system is made of an extruded material such as aluminum.