JPH0243056A - Ink jet recording apparatus - Google Patents

Abstract

PURPOSE:To perform good recording operation by preventing the temp. rise of the ink in a recording head by generating turblent air flow to cool the recording head by said air flow. CONSTITUTION:Blowers (fans) 4a, 4b for blowing cooling air to a recording head 1 are arranged at predetermined angles in opposed relationship and the air flows sent from the respective blowers interact each other to be disturbed and turblent flow is generated in a recording head part 2. The recording head 2 is effectively cooled by said turblent flow. Even when a plurality of recording heads are arranged, the uniform cooling of the respective recording heads can be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an ink jet recording apparatus having means for cooling a recording head.

[Prior Art] An inkjet recording device is a device that performs recording by depositing ink as small droplets on a recording material such as paper through fine holes (orifices) provided in a recording head. It has various configurations.

Further, FIG. 3 shows a schematic diagram of an inkjet recording apparatus having such a configuration in which ink ejected from an orifice is supplied from an ink tank into a recording head via an ink supply pipe or the like.

In this apparatus, during a recording operation, ink 41 is supplied from an ink tank 42 to a liquid chamber 32 of a recording head 31 via an ink supply pipe 35, and the ink in the liquid chamber is further supplied to a flow path 3.
The liquid is supplied to the liquid droplet 3, receives ejection energy according to the recording signal, and is ejected from the orifice 34 as a droplet.

Further, the gear pump 37 is connected to the shaft 44 of the motor 43.
The ink in the ink tank 42 is sent out toward the ink supply pipe 36 by the rotation of the gear 39 into which the
A portion of the ink is then ejected from the nozzle 34. This work is performed prior to printing to wash away the dust attached to the tip of the nozzle, and most of the ink passes through the ink supply pipe 35 to the ink tank together with the ink in the ink chamber that has risen in temperature during the previous printing. 42.

By this operation, most of the ink in the liquid chamber 32 is replaced with new ink that was originally in the ink tank 42. Note that 38 and 40 are gaskets made of rubber or the like to prevent ink from leaking.

[Problems to be Solved by the Invention] In an inkjet recording apparatus, when the ink in the recording head is heated and its temperature rises, the physical properties of the ink may deviate from predetermined values, making it impossible to perform good recording.

For example, when ink becomes hot and its fluidity increases,
The volume of one droplet ejected from the orifice increases beyond the set value, and the image density of the resulting image becomes high.

However, an increase in the temperature of the ink within the recording head is often unavoidable depending on the design of the apparatus, and is particularly noticeable in the case of a type that uses thermal energy as energy for ejecting droplets.

An object of the present invention is to provide a simple and effective means for preventing the temperature of ink within a print head from rising.

[Means for Solving the Problems] A recording apparatus of the present invention is an inkjet recording apparatus having a recording head that performs recording by ejecting ink, and a recording head cooling means for cooling the recording head.
The recording head cooling means is characterized in that the recording head is cooled by air using turbulent airflow.

In the apparatus of the present invention, since turbulence is generated and the recording head is cooled thereby, more efficient cooling can be performed, and a rise in the temperature of the ink in the recording head can be prevented, resulting in a good recording operation. Embodiment] FIG. 1 shows a plan view of a main part of an example of an inkjet recording apparatus of the present invention.

This device includes a print head section 2 in which a print head l having a surface 1a on which orifices (not shown) as ink ejection holes are arranged, and a print head section 2 in which ink is supplied into a liquid chamber (not shown) of the print head. A flowing ink supply pipe 3 and a blower (fan) 4a for blowing cooling air to the recording head 1
, 4b.

The blowers 4a and 4b are arranged to face each other at a predetermined angle, and the flow of air sent from each blower influences each other and is disturbed, thereby generating turbulent flow in the recording head section 2. This turbulent flow effectively cools the recording head.

Further, by generating a turbulent flow of air, the substrate made of an aluminum plate or the like of the recording head can be cooled, and the recording head can be effectively cooled.

This effect is caused by the fact that when a single fan blows air in one direction, as is commonly done, there are areas that are too cold and areas that are not very cold.
In printers that use three or four recording heads, such as full-color printers, some heads may become too cold and other heads may become too hot. In such a case, in terms of color reproducibility, the result will be a low-quality image with a mixture of dark and light colors, but by using turbulent wind as in the present application, it is possible to In other words, not only are there no areas that are too cold, but the turbulent wind is spread to all corners, and as a result, each of the heads is cooled in approximately the same way.

Therefore, the required number of blowers are placed at the required positions to efficiently generate effective cooling turbulence.

As the blowers 4a and 4b, any blowers having rotating blades or the like can be used without limitation as long as they can generate cooling turbulence, and their structure, output, etc. may be appropriately selected according to the configuration of the recording apparatus.

Specifically, it is preferable to use two or more fans and set the fan angle α of 20 to 60'' in FIG.

As mentioned above, by providing a plurality of air blowers and generating turbulent flow, the recording head can be effectively cooled, and this is particularly preferable when a plurality of recording heads are arranged, since each recording head can be cooled evenly. be.

FIG. 2 shows a perspective view of the main parts of another embodiment of the present invention.

This apparatus has a recording head section mounted on a carriage 8, and performs recording by moving and scanning the carriage 8 on a guide rail 6.7 by pulling a wire or belt.

A member that holds the ink ejection part (a part having orifices for ink ejection) of the recording head 1 of the apparatus is formed as a barrier 5 that blocks the wind, and this barrier disturbs the flow of the air from the blower. Creates turbulent flow for air cooling.

Therefore, the position, shape, and size of the barrier are not limited to the illustrated example, but may be various positions, shapes, and sizes that can effectively form turbulent flow.

In addition, the arrangement of the blower and the barrier is as shown in Figure 4.
By arranging the recording material such as the recording paper P so that the wind is directed in the direction of the ink ejection direction X so that the recording material such as the recording paper P can be pressed against the platen 45, it is possible to prevent the recording material from undesirably lifting off from the platen. Another advantage is that an appropriate distance between the recording head and the recording material can be maintained at all times.

[Effects of the Invention] In the inkjet recording apparatus of the present invention, the recording head is efficiently air-cooled by turbulent air flow, the adverse effect on recording performance due to temperature rise of the ink within the recording head is avoided, and the temperature of the ink within the recording head is reduced. can be maintained and good recording operations can be performed.

[Brief explanation of the drawing]

FIGS. 1, 2, and 4 are schematic diagrams of the main parts of an example of an inkjet recording apparatus according to the present invention, and FIG. 3 is a schematic diagram of the inkjet recording apparatus. 1.31: Recording head 2: Recording head section 3.35 + ink supply tubes 4a, 4b = Blower 5: Barrier 6.7: Guide rail 8: Carriage 32: Liquid chamber 33: Channel 34 Niorifice 36: Ink supply tube 37 : Gear pump 38: Packing 39: Gear 40: Packing 41: Ink 42: Ink tank 43: Motor 44: Shaft Patent applicant Canon Co., Ltd.

Claims (1)

[Scope of Claims] 1) In an inkjet recording apparatus comprising a recording head section in which a recording head for discharging ink to perform recording is disposed, and a recording head cooling means for cooling the recording head, the recording head An inkjet recording apparatus characterized in that the cooling means air-cools the recording head using turbulent airflow. 2) The inkjet recording apparatus according to claim 1, wherein the recording head cooling means comprises two or more blowers facing each other at a predetermined angle necessary to generate turbulence around the recording head. 3) The inkjet recording apparatus according to claim 1 or 2, further comprising a barrier for generating turbulence provided around the recording head. 4) The inkjet recording head according to any one of claims 1 to 3, wherein the recording head section has a configuration in which a plurality of recording heads are arranged.