JP3156561B2 - Ink jet recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus capable of exchanging an ink jet head together with a drive circuit thereof, and more particularly, to providing a radiator for radiating heat generated by the drive circuit on a carriage to simplify replacement parts. The present invention relates to an ink jet recording apparatus which has been developed.

[0002]

2. Description of the Related Art Conventionally, an ink jet recording apparatus has been used which performs printing by ejecting ink from a nozzle of an ink jet head onto a recording medium. In this type of inkjet recording apparatus, a carriage movable along a recording area is provided, and the carriage is equipped with an inkjet head and an ink tank for supplying ink to the inkjet head. And by making this ink jet head and ink tank detachable, when the ink is used up or when the ink jet head breaks down,
And when changing the color, it can be easily replaced.

On the other hand, thermal measures are required for the ink jet head. An ink jet head ejects ink by pressurizing an ink chamber communicating with a nozzle with a piezoelectric element or the like. Therefore, a driver IC (drive circuit) for driving the piezoelectric element or the like is provided. Because it occurs. If heat measures are insufficient, for example,
The function of the driver IC itself may be impaired, and the heat reduces the viscosity of the ink, changing the ejection characteristics and making it impossible to obtain desired print quality. Further, there is a problem that the ink dries and solidifies and cannot be ejected from the nozzle.

Therefore, in a conventional ink jet recording apparatus, a heat dissipating member (heat sink) made of a metal having good heat conductivity is attached to an ink jet head having a driver IC as disclosed in Japanese Patent Application Laid-Open No. 5-84911. Thus, a single unit (inkjet unit) is used, and the inkjet unit is a replacement part that can be attached to and detached from the carriage.

[0005]

However, in recent ink jet recording apparatuses, the number of nozzles of the ink jet head has been increased in order to improve the recording resolution, and the driving frequency has been increased in order to increase the recording speed. Therefore, the amount of heat generated by the driver IC is significantly increased, and the heat capacity required for the heat sink is also increased. Therefore,
It is necessary to increase the size of the heat sink or use an expensive material having excellent heat conductivity and heat dissipation, which further increases the cost. Further, it is not preferable to dispose of the expensive material as well as the ink jet unit which is a replacement part in terms of cost and environment.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems. According to the first aspect of the present invention, a heat radiating member is provided on a carriage side, so that the weight and cost of an ink jet head unit which is a replacement part are reduced. It is an object of the present invention to provide an ink jet recording apparatus in which is reduced.

According to a second aspect of the present invention, there is provided an ink jet apparatus which further improves the heat radiation efficiency by closely adhering a heat radiating member as a fixed part and a driving circuit as a heating element provided on the replacement part side. It is an object to provide a recording device.

According to a third aspect of the present invention, in addition to the first or second aspect of the present invention, the ink jet head, which is a replacement part, and the drive circuit are connected by a wiring pattern on a substrate, and they are supported on the substrate. It is an object of the present invention to provide an ink jet recording apparatus which constitutes a unit and has a simplified structure of replacement parts.

According to a fourth aspect of the present invention, in the first aspect of the present invention, when the unit is mounted on the carriage, the unit is connected to the signal cable on the carriage, and the unit is connected to the heat radiating member. It is an object of the present invention to provide an ink jet recording apparatus in which the driving circuit is brought into contact with the ink jet recording apparatus to facilitate the replacement operation.

[0010]

In order to achieve this object, an invention according to claim 1 is an ink jet recording apparatus for performing recording by ejecting ink to a recording medium from a nozzle of the ink jet head. A carriage for detachably mounting a unit including a drive circuit, and a heat radiating member provided on the carriage, and the heat radiating member is located at a position in contact with the drive circuit when the unit is mounted on the carriage. It is characterized by having been provided.

The unit referred to here may include an ink tank containing ink to be supplied to the ink jet head, in addition to the ink jet head and its driving circuit.

In this ink jet recording apparatus, when the unit is mounted on the carriage, the driving circuit of the ink jet head comes into contact with the heat radiation member provided on the carriage.
Therefore, the heat generated by the driving circuit by driving the inkjet head is transmitted to the heat radiating member, and is radiated through the heat radiating member. This prevents heat damage. When replacing the unit, the heat radiation member remains on the carriage,
The same heat dissipating member functions similarly for a new unit. Therefore, the unit does not need to be provided with a means for heat dissipation.

According to a second aspect of the present invention, there is provided the ink jet recording apparatus according to the first aspect, further comprising pressing means for pressing the heat radiation member against the drive circuit when the unit is mounted on the carriage. It is characterized by the following. This pressing means can be realized by, for example, a spring such as a leaf spring or a coil spring, rubber, or the like.

In this ink jet recording apparatus, when the unit is mounted on the carriage, the heat radiating member is pressed against the drive circuit by the pressing means, and the close contact between the heat radiating member and the drive circuit is achieved. Thus, the heat generated by the drive circuit is more reliably transmitted to the heat radiating member.

According to a third aspect of the present invention, there is provided the ink jet recording apparatus according to the first or second aspect,
The unit is provided with a substrate for supporting the inkjet head and its driving circuit, and a wiring pattern provided on the substrate and connecting the inkjet head and its driving circuit.

In this ink jet recording apparatus, the ink jet head and the drive circuit are connected by the wiring pattern on the substrate, and they are supported by the substrate. Thereby, the replacement part is unitized, and the structure is simplified.

According to a fourth aspect of the present invention, there is provided the ink jet recording apparatus according to any one of the first to third aspects, wherein the carriage is movable along a recording area, and the carriage is movable with the unit. A signal cable having a contact connectable to the drive circuit, and the heat radiating member on the opposing surface.

In this ink jet recording apparatus, when the unit which is a replacement part is mounted on the carriage, the ink jet head and the drive circuit are connected to the signal cable on the carriage and at the same time the drive circuit is brought into contact with the heat radiation member. Thereby, the replacement operation can be easily performed.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment embodying an ink jet recording apparatus according to the present invention will be described below with reference to the drawings.

In the schematic perspective view of FIG. 1, the ink jet recording apparatus includes a transport mechanism for transporting a recording medium, for example, a printing paper S by a plurality of rollers 62, and an inkjet head along the recording area of the printing paper S. A carriage mechanism that moves in a direction perpendicular to the transport direction.

The carriage mechanism includes a carriage 9 slidably supported by guide rods 64 and guide rails 66 parallel to the printing paper S. A head unit 11 and an ink tank 30 are detachably mounted on the carriage 9. The head unit 11 is provided with an ink jet head in a downward direction, that is, in a direction facing the printing paper S, as described later, and performs printing by discharging ink onto the printing paper S. The carriage 9 has a CR
It is driven by a motor 68 via a belt 70.

A mechanism for attaching the head unit 11 and the ink tank 30 to the carriage 9 will be described with reference to FIG. FIG. 2 shows the head unit 11 and the ink tank 3.
FIG. 2 shows the carriage 9 in a state where 0 is removed, and a head unit 11 which is an integrated unit including the inkjet head 10. The ink jet head 10 can be attached to and detached from the carriage 9 by detaching the entire head unit 11. FIG. 2 does not show the ink tank 30.

The carriage 9 has on its upper surface a flexible signal cable 4 connected to a recording data generator (not shown).
The end of 8 is attached via a pressing means, for example, a backup rubber 17. At the end of the signal cable 48 on the backup rubber 17, a contact 16 for electrical contact with the substrate 12 of the head unit 11 described later is formed. A concave portion 20 which is opened upward is provided on the upper surface of the carriage 9, and a metal heat sink 18 as a heat radiating member is mounted inside the concave portion 20 so as to be movable in a retracting direction. The opening edge 20a of the recess 20 is formed to protrude inward, and when the head unit 11 is detached, the opening edge 20a is engaged with the lower protruding edge of the heat sink 18 to prevent the heat sink 18 from coming off. It has become so. In addition, the carriage 9 is provided with a hole 9A through which the ink head 10 passes when the head unit 11 is attached to the carriage 9.

The material of the heat sink 18 is suitably aluminum, which has a high thermal conductivity, or an alloy mainly composed of aluminum, among metals. This heat sink 18
When the head unit 11 is mounted on the carriage 9, the head unit 11 is provided at a position that comes into contact with the driver IC 13 of the head unit 11. Pressing means, for example, a leaf spring 19, is provided between the heat sink 18 and the carriage 9, and presses the heat sink 18 against the driver IC 13 when the head unit 11 is attached.

On the other hand, the head unit 11 has an ink jet head 10, a driver IC 13 provided with a drive circuit for driving the ink jet head 10, and a substrate 12 holding these and also provided with a necessary wiring pattern. are doing. The ink jet head 10 and the driver IC 13 are connected to a wiring pattern on the substrate 12.

The wiring pattern on the substrate 12 is such that when the head unit 11 is mounted on the carriage 9, the data signal supplied from the recording data generator is supplied to the driver IC 13 by coming into contact with the contact 16 of the signal cable 48. It is. The inkjet head 10 has a large number of ejection nozzles that open downward, and the driver IC 1
3 is driven based on the data signal, and selectively ejects ink from the ejection nozzles.

A tank holding portion 14 for holding an ink tank 30 is attached to the back surface of the substrate 12. The tank holding portion 14 is provided with an ink receiving port 15 for receiving ink from the ink tank 30. Have been. The head unit 11 is not provided with a component corresponding to the heat sink 18.

FIG. 3 shows the state where the head unit 11 is mounted on the carriage 9 and the ink tank 30. The ink tank 30 stores ink therein, and is provided with an ink sending port 31 for supplying ink to the ink receiving port 15 of the head unit 11. Head unit 11
The ink tank 30 and the ink tank 30 are detachably mounted to the carriage 9 by independent fixing means (not shown), respectively.

Next, the operation of the ink jet recording apparatus will be described.

When the head unit 11 is mounted on the carriage 9, as shown in FIG.
Project through the hole 9A. In this state, the inkjet head 10 can face the printing paper S.
At this time, the substrate 12 of the head unit 11 and the contact 16 of the carriage 9 come into contact with each other, and the data signal from the recording data generator can be transmitted to the driver IC 13 via the wiring pattern provided on the substrate 12. Here, the elasticity of the backup rubber 17 causes the substrate 12 and the contact 16 to be pressed against each other to ensure electrical contact.
At this time, the driver IC 13 of the head unit 11
Is brought into contact with the heat sink 18 of the carriage 9, and heat generated by the operation of the driver IC 13 is transmitted to the heat sink 18. Here, the heat sink 18 and the driver IC 13 are connected to the carriage 9 side and the head unit 11.
Although it is provided separately from the side, the leaf spring 19 presses the heat sink 18 toward the driver IC 13 to ensure the contact.

When the ink tank 30 is further attached to the head unit 11 on the carriage 9 in this state, print recording, which is a basic operation of the ink jet recording apparatus, becomes possible. The printing record is performed as follows.

That is, the rotation of the roller 62 causes the printing paper S
Are conveyed and the line to be recorded is
Sent until it is in a position to face and is stopped there. Then, while the carriage 9 is moved by the CR motor 68, the ink jet head 10 ejects ink in accordance with the recording data sent from the recording data generating device, and print recording is performed. When the recording for one line is completed, the printing paper S is fed by one line by the roller 62, and the recording is continued for the succeeding lines.

The control of the ink jet head 10 at the time of such printing is performed by the driver IC 13 performing various calculations based on the print data transmitted from the print data generator via the signal cable 48 and the contact 16. The driver IC 13 includes the inkjet head 1
A significant amount of heat is generated by the arithmetic processing for the control of zero, and this heat is transmitted to the heat sink 18 in contact with the driver IC 13 and dissipated to the atmosphere. Since the contact between the heat sink 18 and the driver IC 13 is ensured by the elasticity of the leaf spring 19, the efficiency of heat transfer from the driver IC 13 to the heat sink 18 is high, and the driver IC 13 does not become excessively hot. Therefore, such problems as impairment of the function of the driver IC 13 itself, change of ink characteristics due to the heat, deterioration of print quality, and inability to perform print recording are prevented.

In this ink jet recording apparatus, the head unit 11 and the ink tank 30 can be attached to and detached from the carriage 9 as described above. When the ink tank 30 becomes empty, only the ink tank 30 is replaced without changing the head unit 11. When the ink jet head 10 breaks down or changes the color of the ink to be printed, both the ink tank 30 and the head unit 11 are replaced. That is, the head unit 11 and the ink tank 30 are replacement parts. Here, since the heat sink 18 is not included in the head unit 11 or the ink tank 30 which is a replacement part and is attached to the carriage 9 side, the same heat sink 18 is used after the replacement. Although this heat sink 18 is made of metal and is heavy, it is not included in the replacement parts, so that the weight of the replacement parts is light and the cost is low.

As described above in detail, in the ink jet recording apparatus according to the present embodiment, the heat sink 18 of a good heat conductive metal is provided on the carriage 9 and the driver IC is mounted when the head unit 11 is mounted on the carriage 9.
The heat generated by the driver IC 13 when printing is performed is transmitted to the heat sink 18 and is radiated to the atmosphere. Therefore, the function of the driver IC 13 itself is not impaired, the characteristics of the ink are not changed, the print quality is not deteriorated, and the printing cannot be performed. Here, the heat sink 18 is attached to the carriage 9 instead of the head unit 11 or the like which is a replacement part, and the same heat sink 18 is used as it is even when the head unit 11 or the like is replaced. Also, since the head unit 11 is attached to the carriage 9 and comes into contact with the substrate 12, replacement parts such as the head unit 11 are lightweight. Therefore, an excellent ink jet recording apparatus which is easy to replace and has a low component cost is realized.

Since the heat sink 18 is attached to the carriage 9 via the leaf spring 19, when the head unit 11 is mounted on the carriage 9, the heat sink 18 is driven by the elasticity of the leaf spring 19 to drive the driver IC 1
3 and closely contact with each other, so that the efficiency of heat transfer from the driver IC 13 is high.

It should be noted that the present invention is not limited to the above-described embodiment, and it is needless to say that various improvements and modifications can be made without departing from the gist of the present invention. For example, in the above-described embodiment, the plate spring 19 is used as a means for pressing the heat sink 18 against the driver IC 13, but a coil spring, rubber, or the like may be used instead.

Although the heat sink 18 is provided on the carriage 9 side and the head unit 11 side is not provided with an equivalent one, the heat sink is divided into two and one is provided on the carriage 9 side and the other is provided on the head unit side. It may be provided on the 11 side. Even in this case, the heat sink is superior to the conventional ink jet recording apparatus in which all the heat sinks are provided on the head unit side.

[0039]

As described above, according to the first aspect of the present invention, the heat radiating member is provided on the carriage side.
Thus, there has been provided an ink jet recording apparatus in which the weight and cost of replacement parts are reduced.

According to the second aspect of the present invention, there is provided an ink jet recording apparatus in which a heat radiating member as a fixed part and a driving circuit as a heating element provided on the replacement part are brought into close contact with each other to improve heat absorption efficiency. Have been.

According to the third aspect of the present invention, the ink jet head and the drive circuit are connected by the wiring pattern on the substrate and are supported on the substrate to constitute a unit, thereby simplifying the structure of the replacement part. A recording device is provided.

According to the fourth aspect of the present invention, when the unit is mounted on the carriage, the unit is connected to the signal cable on the carriage and at the same time, the drive circuit of the unit is brought into contact with the heat radiating member to facilitate the replacement operation. A recording device is provided.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a schematic configuration of an ink jet recording apparatus.

FIG. 2 is a sectional view showing a configuration of a carriage and a head unit in a separated state.

FIG. 3 is a cross-sectional view showing a mounted state of a carriage and a head unit and also showing an ink tank.

[Explanation of symbols]

 Reference Signs List 9 carriage 10 inkjet head 11 head unit 12 substrate 13 driver IC (drive circuit) 16 contact 18 heat sink (radiator) 19 leaf spring (pressing means) 48 signal cable S printing paper (recording medium)

Claims (4)

(57) [Claims] 1. An ink jet recording apparatus for performing recording by ejecting ink from a nozzle of an ink jet head onto a recording medium, comprising: a carriage for detachably mounting a unit including the ink jet head and a drive circuit thereof; A heat radiation member provided on a carriage, wherein the heat radiation member is provided at a position in contact with the drive circuit when the unit is mounted on the carriage. 2. The ink jet recording apparatus according to claim 1, further comprising a pressing unit that presses the heat radiating member against the drive circuit when the unit is mounted on the carriage. apparatus. 3. The ink jet recording apparatus according to claim 1, wherein the substrate supporting the ink jet head and a driving circuit thereof, and the ink jet head provided on the substrate and the driving circuit thereof are provided. An ink jet recording apparatus, comprising: a wiring pattern for connecting to the unit. 4. The ink jet recording apparatus according to claim 1, wherein the carriage is movable along a recording area.
An ink jet recording apparatus comprising: a signal cable having a contact connectable to the drive circuit on a surface facing the unit; and the heat radiating member.