JPH01105597A - Electronic device with noise countermeasure - Google Patents

Abstract

PURPOSE:To prevent a noise without employing a flat cable by inserting leads connected at one end to the housing of a moving unit and at the other to a stationary side into a surface acoustic wave covering member made of a conductive material, and deflecting it. CONSTITUTION:One end of a coil spring 33 is connected by a bracket 34 to a carriage 13. The other end of the spring 33 is connected by a bracket 35 to the part of a housing 5. One end of a coil spring 65 is connected by a bracket 66 to a carriage 48. The other end of the spring 65 is secured by a bracket 67 to a chassis 42. A lead 30 is inserted into the spring 35, and a lead 63 is inserted into the spring 65. Accordingly, even if a high voltage is applied to the parts of the leads 30, 63, a noise is prevented by the shielding effects of the springs 33, 65.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to an electronic device with noise countermeasures applied to, for example, an image information reading device.

(Conventional technology) image scanners, printers, and fax machines.

Image information reading devices used in electronic filing devices, etc. irradiate exposure light onto a document placed on a document placement surface, and convert light reflected from the document or light transmitted through the document into electrical signals using a photoelectric converter. By converting, a desired image signal can be input to a host computer or the like. The scanner as a reading means equipped with the above-mentioned photoelectric converter is provided on a carriage that is relatively reciprocated along the document placement surface by a well-known driving means, and these operations are controlled or controlled. Signal processing and the like are performed by a control circuit etc. housed within the main body of the device.

In addition to the photoelectric converter, electrical components such as a dimming sensor, an amplifier board, or a light source may be mounted on the carriage. It is necessary to supply power to these electrical parts from the power supply section and to transmit electrical signals to and from the control circuit section, etc., but since the carriage moves back and forth relative to the main body of the device, the carriage Flexible flat cables were used to ensure unobstructed movement. This flat cable is provided with a plurality of conductive paths parallel to each other corresponding to various electrical components attached to the carriage.

(Problems to be Solved by the Invention) Some parts of this type of device generate high voltages of several thousand volts during operation, and noise is likely to be generated especially when high voltages are applied to the flat cable. To prevent the generation of noise, it is desirable to use lead wires that are each individually covered with a conductive material, but many lead wires are connected to a moving member such as a carriage. In such cases, the lead wires tend to come apart, and there is a risk that the lead wires may interfere with surrounding components or be forcibly bent with a small radius of curvature, resulting in problems such as wire breakage. There are also special flat cables that can suppress noise, but they are expensive.

Therefore, an object of the present invention is to provide an electronic device that can prevent noise generation without using a special flat cable.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention is provided with a conductive material that is movable relative to a fixed member and that has built-in electrical components. a moving body having a casing; a lead wire having one end connected to an electrical component of the moving body and the other end drawn out of the casing; one end connected to the casing of the moving body and another lead wire; An elastic covering member made of a conductive material is provided, the end side of which is connected to the fixed member, the lead wire is inserted inside, and the elastic covering member is bent into a shape that does not impede the movement of the movable body.

(Function) In the electronic device of the present invention having the above configuration, power is supplied to the electric device mounted on a moving body such as a carriage or signals are transmitted through the lead wire. These lead wires are inserted through elastic sheathing members such as conductive coil springs, so even if high voltage or high-frequency signals are applied to the wires, noise generation is suppressed due to the shielding effect of the sheathing member. Ru. In addition, each lead wire is inserted into the covering member all at once, and can be bent smoothly while maintaining an appropriate curvature.
When the movable body moves, the lead wire is guided by the elastic covering member and is also protected.

Therefore, it is possible to prevent the lead wires from coming apart or interfering with other parts.

(Example) An example of the present invention will be described below with reference to the drawings.

The image information reading device 1 as an example of an electronic device shown in FIG.
This is an image scanner that reads images and outputs image signals to an external device 2 such as a host computer. This reading device 1
The device main body 3 has a first metal housing 4 and a second metal housing 5 divided into upper and lower parts, and a removable synthetic resin cover 6 surrounding the outside of these housings 4.5. A power supply section, a control circuit board, a scanner 7 as an example of a reading means, etc. (not shown) are built into the housings 4 and 5. The circuit board includes, for example, a GPIB interface port, a scanner processing board, or a scanner image processing board. This circuit board is
Interface connector and cable 8 for connecting external devices
It is connected to the external device 2 via. External devices 2 include various computers, printers, electronic filing devices, and the like.

Further, a pivot 9 is provided on one side (the front end in the illustrated example) of the first casing 4, and the second casing 5 is supported by this pivot 9 so as to be openable and closable in the vertical direction. FIG. 7 shows a state in which the housing 5 is closed, and FIG. 8 shows a state in which the housing 5 is opened. The second housing 5 can be held at an appropriate opening angle by a stopper 10.

A platen glass 11 used as a document placement surface is provided on the top side of the second housing 5 in the drawing.

On the back side of the platen glass 11, the scanner 7 is arranged so as to be movable in parallel along the platen glass 1. As shown in FIG. 9, the scanner 7 includes a carriage 13 made of a conductive material such as metal, which constitutes the housing of the moving body.
In addition, a straight tube fluorescent lamp 14 or a CC as an example of a light source is used.
Photoelectric converter such as D line sensor 15. It is equipped with electrical components such as a lamp heater (not shown), and is also provided with optical system members 16 such as a rod lens array. Furthermore, the carriages 1 and 3 include a dimming sensor 18 (see Figure 1) for keeping the light intensity of the lamp 14 constant, and an amplifier with a built-in amplifier circuit for amplifying the output from the photoelectric converter 15. Electrical components such as a board (not shown) are provided.

As conceptually shown in FIG. 1, the scanner 7 includes a motor 20 equipped with a speed reducer, a driving sprocket 21, a driven sprocket 22. A guide 25 and a rail shaft 26 are driven by a driving means 24 consisting of a timing belt 23 and the like.
It is designed to be able to reciprocate along a predetermined stroke in the direction of arrow A in FIG. A roller 27 that rolls on a guide 25 is provided at the end of the carriage 13.

Lead wires 30 constituting a wire harness are connected to each of the electrical components mounted on the carriage 13. Each lead wire 30 is drawn out of the carriage 13, and a connector 31 is attached to the other end of the lead wire 30. This connector 31 is connected to a connector (not shown) provided on the device main body 3 side, and is also connected to a control circuit and a power supply section in the device main body 3 via this connector. As each lead wire 30, a well-known wire having a core wire coated on the outside with an insulating material is used.

Each lead wire 30 is inserted into a coil spring 33, which is an example of an elastic covering member made of a conductive material such as metal. This coil spring 33 is highly flexible and is made of tightly wound spring steel wire, and one end of the coil spring 33 is connected to the carriage 1 by a bracket 34 (see Fig. 2).
Connected to 3. A bracket 35 is provided on the other end side of the coil spring 33.
5 is connected to a part of the housing 5 as a fixed side member. The coil spring 33 is grounded to the housing 5. This coil spring 33 is placed inside a gutter-shaped guide member 37 in a substantially U-shaped bent state as shown in FIGS. 2 and 4. The guide member 37 has a substantially U-shaped cross section and is provided in the housing 5 along the moving direction of the carriage 13. This guide member 3
A resin lining layer 38 is provided on the inner surface of the spring 7 in order to improve sliding against the spring 33 and to prevent generation of sliding noise.

A platen glass 1 is provided on the top side of the apparatus main body 3 described above in the drawing.
A transmission unit 41 having a size sufficient to cover 1 is provided. The transmission unit 41 includes a metal chassis 42 in the shape of a rectangular frame, and a synthetic resin housing 43 that covers the outside of the chassis 42. This transmission unit 41
is pivotally connected to the second housing 5 by a hinge 45 so as to be openable and closable in the vertical direction. This hinge 4-5 is provided at a position opposite to the aforementioned pivot portion 9, that is, on the rear side of the second housing 5.

The bottom side of the transmission unit 41, that is, the platen glass 11
A light-transmitting plate 46 is provided on the side facing the. The transparent plate 46 is made of a material that transmits and diffuses light, such as a white or milky white resin panel. A light source section 47, which is a moving body, is provided on the back side of the transparent plate 46 at a position corresponding to the scanner 7.

This light source section 47 is housed in a carriage 48 as a housing made of a conductive material such as metal, and includes a straight tube fluorescent lamp 49 as an example of a light source, a heater for heating the lamp (not shown), and a lamp 49 that maintains a constant amount of light. It is equipped with electrical components such as a dimming sensor 50 for As conceptually shown in FIG. 1, the carriage 48 is connected to a motor 55 equipped with a speed reducer and a driving sprocket 56. Driven side sprocket 5
By means of a drive means 59 consisting of a 7° timing belt 58 or the like, the arrow B in FIG.
It is possible to move back and forth in the direction. - A resin slider 62 that slides on a guide 60 is provided at the end of the carriage 48.

Lead wires 63 constituting a wire harness are connected to each of the electrical components mounted on the carriage 48. Each lead 1j163 is drawn out to the outside of the carriage 48, and the connector 6 is connected to the other end of the lead wire 63.
4 is installed.

This connector 64 is connected to a connector (not shown) provided on the chassis 42 side, and is also connected to a control circuit section and a power supply section in the apparatus main body 3 via this connector. The lead wire 63 is a core wire whose outer side is covered with an insulating material like the lead wire 30 described above.

Each lead wire 63 is inserted inside a coil spring 65 made of a conductive material such as metal. Like the spring 30 described above, the coil spring 65 is made of tightly wound spring steel wire and is highly flexible, and its negative end is fixed to the carriage 48 by a bracket 66. A bracket 67 is provided on the other end side of the coil spring 65, and this bracket 67 is fixed to the chassis 42 as a fixed side member. The coil spring 65 is grounded to the chassis 42. As shown in FIGS. 3 and 5, the coil spring 65 is placed inside the gutter-shaped guide member 70 in a substantially U-shaped bent state. This guide member 70 is provided on the chassis 42 along the moving direction of the carriage 48. This guide member 70
A resin lining layer 71 is provided on the inner surface of the spring 65 in order to improve sliding against the spring 65 and to prevent generation of sliding noise.

Next, the operation of the above embodiment device 1 will be explained.

When reading the original S (FIG. 1) placed on the platen glass 11, in the case of a reflective original, 1. With the transmission unit 41 closed from above the document, the lamp 14 of the scanner 7 is turned on, and the scanner 7 is moved back and forth in the direction of arrow A in FIG. The light emitted from the lamp 14 is reflected on the surface of the document, and the image thereof is input to the photoelectric converter 15 via the optical system member 16. Therefore, when reading a reflective type original, the lamp 49 of the transmission unit 41 is not turned on, and the transparent plate 46 of the transmission unit 41 is used as a document holder. 1. - On the other hand, when reading a transmission type document 1q, the lamp 49 of the transmission unit 41 is turned on. -Then, the scanner 7 moves in the direction of arrow A in the same way as when reading a reflected light document, and
By moving the carriage 48 of the transmission unit 41 in the direction of arrow B in synchronization with the scanner 7, light that has come out of the lamp 49 and passed through the original is inputted to the photoelectric converter 15 via the optical system member 16. . Therefore, in this case, the transmission unit 41 has both the function of irradiating the transmitted light and the function of holding the document.

The image information input to the photoelectric converter 15 is digitized by the A/D conversion circuit and output to the external device 2 via the cable 8. The selection of the above-mentioned reflective and transmissive originals is performed by operating keys provided on the operating section 72.

, when the carriage 13.48 moves along the rail shaft 26.61 as described above, one spring 33
As the carriage 13 moves, the guide member 37 follows the movement of the carriage 13 by moving in parallel while remaining bent in a U-shape. The other spring 65 also follows the movement of the carriage 48 by moving in parallel inside the guide member 70 in a U-shaped state.

In this way, each spring 33.65 bends in a U-shape while maintaining a substantially constant curvature, so the lead wire 30.63 inserted therein bends with a relatively large radius of curvature and bends toward the carriage 13.48. Follow movement. Moreover, since each lead wire 30.63 is held together by the spring 33.65, the lead wires 30.63 are smoothly guided along the guide member 37.70 without coming apart, and each lead wire 30.63 is guided smoothly along the guide member 37.70. 63 is spring 3
3.65. Also, lead wire 30.6
Even if a high voltage is applied to a portion of lead wire 30.
Each of the springs 63 itself is individually covered with an insulating material, and the outer side of the springs 33 and 65 is covered with a shielding effect, thereby reliably preventing noise from being generated.

Note that the present invention can also be applied to an image information reading device that reads only reflected light documents, and in this case, instead of providing the transmission unit 41, a simple document cover is replaced with the platen glass 11.
It may be provided on the top so that it can be opened and closed. In addition to image information reading devices, the present invention can also be applied to electronic devices such as wire harnesses that require noise countermeasures, such as printers and facsimiles.

It can be similarly applied to various electronic devices such as word processors and personal computers.

[Effects of the Invention] As described above, according to the present invention, power can be supplied and signals can be transmitted through a lead wire inserted into an elastic covering member such as a coil spring without using a special and expensive flat cable. In addition to being able to smoothly guide each lead wire one by one with the covering member,
Noise generation can also be prevented.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a perspective view conceptually showing a part of an image information reading device, FIG. 2 is a front view showing a carriage portion of a scanner and a coil spring, and FIG. 3 4 is a sectional view showing a part of the carriage and the guide member shown in FIG. 2, and FIG. 5 is a front view of the carriage shown in FIG. 3. 6 is a perspective view of the image information reading device and external equipment seen from the back side; FIG. 7 is a perspective view of the image information reading device with the cover removed; FIG. The figure is a perspective view with the housing opened, and FIG. 9 is a vertical cross-sectional view conceptually showing two parts of the image information reading device. 1... Image information reading device, 3... Device body, 4.5
... Housing (fixed side member), 13... Carriage (housing of moving body), 24... Drive means, 30... Lead wire, 33... Coil spring, 37... Guide member, 42... Chassis (fixed side member), 48... Carriage (casing of moving body), 59... Drive means, 63...
... Lead wire, 65 ... Elastic coating member (coil spring), 70 ... Guide member. Applicant's representative Patent attorney Takehiko Suzue Figure 1, 13 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9

Claims (4)

[Claims] (1) A movable body equipped with a casing made of a conductive material that is movable relative to a fixed member and contains electrical components, and one end of which is connected to the electrical components of the movable body and the other end. A lead wire whose side is drawn out to the outside of the casing, one end side connected to the casing of the movable body, and the other end connected to a fixed side member, and the lead wire is inserted inside the movable body. an elastic covering member made of a conductive material that is bent into a shape that does not impede the movement of the material;
An electronic device with noise countermeasures characterized by being equipped with the following. (2) The electronic device provided with noise countermeasures according to claim 1, wherein the elastic covering member is a coil spring. (3) The electronic device provided with noise countermeasures according to claim 1, wherein the coil spring is bent into a substantially U-shape between the fixed member and the movable body. . (4) The electronic device provided with noise countermeasures according to claim 1, wherein the coil spring is grounded to a metal fixed member.