JPH0911581A - Carriage connecting cable and printer using the same - Google Patents

Abstract

PURPOSE: To provide an inexpensive carriage connecting cable for a serial printer capable of certainly preventing the generation of EMI noise and not requiring an especially wide arranging space. CONSTITUTION: First and second flexible cables 11, 12 are superposed one upon another to form a connection cable 10. A plurality of the conductive wires P arranged in both cables 11, 12 are alternately used as signal wires 14 or earth wires 15. In the relation between the cables 11, 12, the signal wires 14 and the earth wires 15 are positionally opposed to each other. By this constitution, the signal wires 14 are surrounded by the earth wires 15 and certainly shielded to prevent the generation of noise.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer in which a print head is moved by a carriage. And in particular, it relates to a carriage connection cable for electrically connecting the moving carriage and the printer body.

[0002]

2. Description of the Related Art In a so-called serial printer, characters are printed on a printing material by ejecting ink from the printing head while moving the printing head in parallel with the printing material such as printing paper. In a general printer, a print head is fixedly arranged on a carriage that moves in parallel, so that the print head moves in parallel with respect to the printing material. On the carriage, in addition to the print head, a fan for cooling and a motor for driving it, an encoder for detecting the position and moving direction of the carriage, a thermistor for temperature detection, and the width of printing material are detected. It is often equipped with various devices such as sensors.

Print heads and fan motors need to be supplied with relatively large currents to operate them. Further, regarding elements such as an encoder, a thermistor, and a sensor, various signals are exchanged with a control device arranged in the printer body. In order to supply current to the print head and exchange signals with the encoder, it has been widely practiced to connect the printer body and the carriage with a flexible electric cable, that is, an electric cable with flexibility. ing.

[0004]

With respect to the above electric cable, electromagnetic interference noise (EMI noise) may occur when a supply current or a signal flows inside the electric cable. The EMI noise becomes particularly noticeable when the signal transfer speed is increased with the increase in printing speed and the increase in the number of pins of the print head.

In order to prevent the generation of this EMI noise,
Conventionally, a flexible cable with a shield having a structure in which a shield metal is evenly attached to a flexible cable is used, a shield plate is added to the flexible cable, or a ferrite core is placed in an appropriate place on the flexible cable. Noise countermeasures are taken.

However, there have been problems such that a large amount of cost is required for these noise countermeasures, and a space for installing a shield plate, a ferrite core, etc. is required.

The present invention has been made in order to solve the above-mentioned problems, and can reliably prevent generation of noise, is inexpensive, and is for connecting a carriage which does not require a particularly large installation space. It is intended to provide a cable and a printer.

[0008]

To achieve the above object, a carriage connecting cable according to the present invention is a first flexible cable having a plurality of conductive wires arranged in parallel with each other and used as signal wires or ground wires. Cable,
And a second flexible cable which is arranged in parallel with each other and has a plurality of conductive lines used as signal lines or ground lines and which is arranged so as to face the first flexible cable. Then, the conductive wire in the first flexible cable and the second flexible cable, which surrounds at least one signal wire in the first flexible cable or the second flexible cable, is used as a ground wire. The signal line referred to here is a line for passing a signal to an encoder or the like, or a current for supplying a print head or the like.

The present invention includes not only the case where all the signal lines in the first flexible cable and the second flexible cable are surrounded by the ground line, but also the case where some signal lines are surrounded by the ground line.

As a more specific structure, the signal line and the ground line are alternately arranged in the first flexible cable, and the second flexible cable is provided.
Signal lines and ground lines are alternately arranged in the flexible cable, and the signal lines in the first flexible cable and the ground lines in the second flexible cable face each other, and further, the signal lines in the second flexible cable. It is possible to adopt a configuration in which the first flexible cable and the second flexible cable are overlapped with each other so that and the ground wire in the first flexible cable face each other.

From the viewpoint of preventing noise generation, it is desirable that the first flexible cable and the second flexible cable are in surface contact with each other in a close contact state. In some cases, the first flexible cable and the second flexible cable
It is also possible to bond the flexible cable with an adhesive or another method.

In order to achieve the above object, the printer according to the present invention has a carriage that moves in parallel with respect to the printing material, a print head disposed on the carriage, a printer main body and a carriage. And a carriage connecting cable connected to the printer, wherein the cable having the above-mentioned configuration is used as the carriage connecting cable.

[0013]

In the cable for connecting the carriage of the present invention, the first
One of the plurality of signal lines in the flexible cable and the second flexible cable or a bundle of several of them is used as a line for supplying a current to a print head or the like, or a signal line for an encoder or the like. Used. If each of these signal lines is surrounded by a conductive wire used as a ground line, each signal line can be reliably shielded and noise can be prevented.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a cable for connecting a carriage according to the present invention and a main part of a printer using the same. The printer shown here includes a cable connection terminal 2 provided on the printer body 1, a carriage 4 supported by a linear guide rod 3, and a print head 5 fixedly installed on the carriage 4. Have Carriage 4
The front end portion of is fixedly connected to an annular conveyor belt 6, and the conveyor belt is driven by a motor 7 to move in both forward and reverse directions. The linear encoder 16 provided on the side surface of the carriage 4 optically reads the scale 17,
A signal relating to the position of the print head 5 is output.

When the conveyor belt 6 moves around, the carriage 4 connected to the conveyor belt 6 moves in parallel while being guided by the guide rods 3, whereby the print head 5 fixed on the carriage 4 is moved as shown by arrow A. , Parallel movement with respect to the paper 8 as a printing material, that is, main scanning movement.
The sheet 8 is conveyed in a direction perpendicular to the moving direction of the print head 5 as indicated by an arrow B by the action of a conveying system (not shown).

The cable connecting terminal 2 of the printer body 1 and the cable connecting terminal 9 of the carriage 4 are formed by superimposing a first flexible cable 11 and a second flexible cable 12 on each other, and a carriage connecting cable 10 is formed.
Electrically connected by Both of these flexible cables 11 and 12 are so-called FFC (Flex
ible flat cable), and is formed, for example, by arranging a plurality of conductive lines P flat and coating them with a thin flexible insulating material 13, as shown in FIG.

The first flexible cable 11 and the second flexible cable 12 are in surface contact with each other in an intimate contact state, and in the contact state, the conductive wires P in both cables are positionally opposed to each other. ing. In this embodiment, a plurality of conductive wires P in both cables 11 and 12 are used.
Are alternately used as the signal line 14 and the ground line 15.
Moreover, in the relationship between the first flexible cable 11 and the second flexible cable 12, the signal line 14 and the ground line 15 face each other. That is, when looking at any one signal line 14 in the first flexible cable 11 or the second flexible cable 12, the ground line 15 in both flexible cables 11 and 12 is surrounded by the signal line 14.
Surrounded by

Each of the signal lines 14 is used as a power supply line for supplying a current to the print head 5, or a line bundle obtained by bundling several of them is related to the linear encoder 16. It is used as a signal line for passing a signal. A cooling fan may be provided on the carriage 4, and in that case, one or several signal lines 14 are used as a power supply line to a motor for driving the fan. In addition, a thermistor for temperature detection, a sensor for paper width detection, or the like may be disposed on the carriage 4, in which case one or several signal lines for passing signals relating to these elements are provided. The signal line 14 of the book is used.

Since the printer of this embodiment is constructed as described above, the carriage 4 moves at a predetermined speed to move the print head 5 in the main scanning direction with respect to the paper 8, and the paper 8 also moves at a predetermined speed. Move in sub-scan. While the print head 5 scans and moves, an electric current is supplied to the print head 5 based on the position information of the print head 5 detected by the linear encoder 16, whereby, for example, ink is ejected from the print head 5 to obtain a desired character. Etc. are printed on the paper 8. When the print head 5 scans and moves, the carriage connecting cable 10 freely deforms following the movement of the carriage 4.

In the conventional cable, EMI noise may be radiated from each signal line 14 in the cable 10 for connecting the carriage during the printing operation. However, as in this embodiment, each signal line 14 has a EMI noise. If the surroundings are surrounded by the ground wire 15, the generation of such noise can be reliably prevented. In this case, a special element for noise prevention such as a shield plate or a ferrite core is not required, so that the space for installing them inside the printer can be saved. Also, the cost of manufacturing cables and printers is reduced.

In order to reliably shield the signal lines 14 in the first flexible cable 11 and the second flexible cable 12, those cables 11 and 1 are shielded.
It is desirable for 2 to maintain a close contact state in a wide area. However, when the carriage connecting cable 10 is deformed following the movement of the carriage 4, the first flexible cable 11 and the second flexible cable 12 may partly separate from each other. Both cables 1
In order to prevent 1 and 12 from separating even a little,
Both cables may be adhered by an adhesive or other method.

The present invention has been described above with reference to the preferred embodiments, but the present invention is not limited to the embodiments and can be variously modified within the technical scope described in the claims. For example, in the above embodiment, the FFC (Flexible
Although the present invention is applied to a flat cable, various other flexible cables such as so-called FPC (Fl
It goes without saying that the present invention can be applied to an exible pattern circuit. FPC is a flexible, long and sheet-like substrate on which a plurality of conductive patterns are formed.
The conductive patterns are used as conductive lines such as signal lines or ground lines. In the carriage connection cable shown in FIG. 2, the signal lines and the ground lines are alternately arranged to arrange the ground lines around all the signal lines. It is also within the technical scope of the present invention to enclose only a specific signal line, which is desired to be prevented, with a ground line.

[0023]

According to the cable for connecting a carriage of the first aspect and the printer of the fourth aspect, the conductive line used as the signal line is surrounded by the conductive line used as the ground line to thereby form the signal line. Can be reliably shielded to reliably prevent the generation of EMI noise. Further, since no shield plate or ferrite coil is used, it is inexpensive and does not require a particularly large installation space for installing those elements.

According to the carriage connecting cable of the second aspect and the printer of the fifth aspect, the FFC (Flexib
The cable for connecting the carriage according to claim 1 and the printer according to claim 5 can be configured with an extremely simple configuration using a le flat cable.

According to the carriage connecting cable and the printer of the sixth aspect, the shield effect using the ground wire can be more effectively exhibited by bringing the pair of cables into close contact with each other. it can.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an essential part of an embodiment of a cable for connecting a carriage according to the present invention and an embodiment of a printer using the same.

FIG. 2 is a perspective view showing a cross section of a main part of an embodiment of a cable for connecting a carriage according to the present invention.

[Explanation of symbols]

 1 Printer Main Body 2 Cable Connection Terminal (Printer Side) 3 Guide Rod 4 Carriage 5 Print Head 6 Conveyor Belt 7 Carriage Drive Motor 8 Paper (Printing Material) 9 Cable Connection Terminal (Carriage Side) 10 Carriage Connection Cable 11 1st Flexible cable 12 Second flexible cable 13 Insulation coating material 14 Signal wire 15 Ground wire 16 Linear encoder 17 Scale P Conductive wire

Claims (6)

[Claims] 1. A carriage connecting cable for electrically connecting a printer main body and a carriage, wherein a first flexible cable having a plurality of conductive wires arranged in parallel with each other and used as signal lines or ground lines, A plurality of conductive wires arranged in parallel and used as signal lines or ground lines, and a second flexible cable arranged to face the first flexible cable, and a first flexible cable Alternatively, a cable for connecting a carriage, characterized in that a conductive wire in the first flexible cable and the second flexible cable, which surrounds at least one signal wire in the second flexible cable, is used as a ground wire. 2. The carriage connecting cable according to claim 1, wherein the signal line and the ground line are alternately arranged in the first flexible cable, and the signal line and the ground line are alternately arranged in the second flexible cable, The signal line in the first flexible cable and the ground line in the second flexible cable face each other, and the signal line in the second flexible cable and the ground line in the first flexible cable face each other. A cable for connecting a carriage, characterized in that the first flexible cable and the second flexible cable are superposed on each other. 3. The carriage connecting cable according to claim 1 or 2, wherein the first flexible cable and the second flexible cable are in surface contact with each other in a close contact state. 4. A printer having a carriage that moves parallel to a printing material, a print head disposed on the carriage, and a carriage connecting cable that electrically connects the printer main body and the carriage, The carriage connecting cable includes a first flexible cable having a plurality of conductive wires arranged in parallel with each other and used as a signal line or a ground wire, and a plurality of carriage connecting cables arranged in parallel with each other and used as a signal line or a ground wire. A second flexible cable which has a conductive wire and is arranged to face the first flexible cable, and surrounds at least one signal line in the first flexible cable or the second flexible cable, The conductive wires in the 1st flexible cable and the 2nd flexible cable are Printer, which comprises using as a line. 5. The printer according to claim 4, wherein the signal line and the ground line are alternately arranged in the first flexible cable, the signal line and the ground line are alternately arranged in the second flexible cable, and The signal line in the first flexible cable and the ground line in the second flexible cable face each other, and further, the signal line in the second flexible cable and the ground line in the first flexible cable face each other. A printer characterized by stacking a first flexible cable and a second flexible cable. 6. The printer according to claim 4 or 5, wherein the first flexible cable and the second flexible cable are in surface contact with each other in a close contact state.