JPH02190338A - inkjet head - 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 Field of Application J] The present invention applies hot melt ink to an inkjet head.

[Prior art] The conventional inkjet head is manufactured by Japanese Patent Publication No. 61-98547.
As disclosed in the publication, hot melt ink is used, and a nozzle forming plate having the required nozzles is immersed in the liquid phase hot melt ink behind the nozzle forming plate and the liquid phase hot melt ink is jetted. a container for storing the bulk hot melt ink, an ink tank to which hot melt ink in a liquid phase is supplied from the container and stored therein, and a hot melt ink in a liquid phase in the ink tank to a nozzle forming plate. In order to melt the hot melt ink in the pressure generating means, nozzle forming plate, ink flow path, ink tank, and container, the heating element is in contact with the forming members of the ink flow path and ink tank. It had become.

In the above configuration, each member of the hot melt ink passage is made of a thermally conductive material, so that the heat generated by the heating element can be conducted to the entire inkjet head. However, due to the structure, the heat conduction system up to the vicinity of the pressure generating means is configured to take time for heat conduction.

[5! ! However, in the conventional example described above, the heating element is in contact with the forming members of the ink flow path and ink tank, so when the heating element starts generating heat, the hot melt ink is removed from the solid phase. The order of phase change to liquid phase is ink tank -> ink channel -> nozzle forming plate -> pressure generating means. Therefore, there is a problem in that it takes a long time to warm up the pressure generating means until it becomes operational.

The present invention is intended to solve the above-mentioned problems, and its purpose is to instantaneously change the phase of the hot melt ink near the pressure generating means from a solid phase to a liquid phase, so that the pressure generating means can operate. To provide an easy-to-use inkjet head by shortening the warm-up time until the temperature rises.

[Means for Solving the Problems] The inkjet head of the present invention uses hot melt ink, and includes a heat generating means for changing the phase of the hot melt ink from a solid phase to a liquid phase, a container for storing the bulk hot melt ink, The present invention is characterized in that it includes a jetting means for jetting hot melt ink in a liquid phase, the heating means and the jetting means are brought into contact with each other, and a heat insulating means is provided between the heating means and the container.

[Example] FIG. 1 is a schematic cross-sectional view in an example of the present invention,
The inkjet head 101 is mounted on a carriage (not shown) that reciprocates in the axial direction of the platen 102. A nozzle forming plate 103 having required nozzles in the axial direction of the platen 102 is fixed to an ink tank 108 at a constant distance from a recording paper 104 which is wound around the platen 102 and is movable in the direction of arrow AB. A necessary vibrator 106, which is immersed in the hot melt ink 105A behind the nozzle forming plate 103, is attached to the back of the nozzle forming plate 103 with a minute interval corresponding to the thickness of the spacer 107A. The vibrator 106 vibrates at high frequency in the direction of arrow C-D, pressurizes the liquid-phase hot melt ink 105A, and jets it from the nozzle of the nozzle forming plate 103.

The ejected droplets of hot melt ink 105A adhere to the recording paper 104 to form characters, lines, etc. The ink tank 108 stores hot melt ink 105B. The nozzle forming plate 1 is placed at a small distance from the vibrator 106.
A heating element support plate 10 attached to face 03
9 holds a heating element 110. The heating element 1i0 is not in contact with any member other than the heating element support plate 109. The ink flow path 111 that guides the hot melt ink 105B to the vicinity of the vibrator 108 is connected to the ink tank 108 and the heating element support plate 1.
09 and the nozzle forming plate 103 at a minute interval. In this embodiment, the spacing is 2 mm or less.

Referring to FIG. 2, the vicinity of the ink tank 108 will be explained. Inside the ink tank 108, a plurality of fins 112 made of a thermally conductive material are arranged at regular intervals, and a heating element support plate is arranged. The heating element support plate 109 is attached to the heating element support plate 109 by a means that allows good heat conduction from the heating element 109. In this embodiment, the fin 112 and the spacer B1 made of thermally conductive material
It is attached to the heating element support plate 109 by a shaft 116 through a hole attached to 15, and the fin thickness is 0.1
~0.2 mm, and the fin spacing was 2 mm or less. The heat generated by the heating element 110 is supplied to the hot melt ink 105B via the heating element support plate 109 and the fins 112.

Referring to FIG. 1 again, a container 113 is attached to the upper part of the ink tank 108 for storing the bulk hot melt ink 105-1. Container 113 and heating element 110
The interval E is an air layer constituting the heat insulating means, and in this embodiment, the interval is 2 mm. Incidentally, instead of the air layer, a heat insulating material such as a foamed material or a plastic material may be used as a heat insulating means. In addition, a wall made of these heat insulating materials is provided on the surface of the heating element 110 on the side of the container 113, and the container 11
3 may be composed of these heat insulating materials. Attached to the top of the container 113 is a lid 114 that can be opened and closed to replenish the bulk hot melt ink 105-1. Container 113
The lower part of the lumpy hot melt ink 105-1 inside is in contact with the fins 112, and the heat generated by the heating element 110 is supplied through the fins 112. In the above configuration, each member of the hot melt ink passages 105A and 105B is made of a thermally conductive material. Therefore, the heat generated by the heating element can be conducted throughout the inkjet head 101. In this embodiment, the nozzle forming plate 103 and the fins 112 are made of stainless steel, the ink tank 108 and the heating element support plate 109 are made of aluminum, and the container 113 and the lid 11 are made of aluminum.
Although heat-resistant plastic was used in No. 4, the material is not limited to this.

Next, to explain the operation of the above configuration, when the heating element 110 generates heat to perform a printing operation, the heating element support plate 109 is heated, and the hot melt ink 105A near the vibrator 106 is first melted, allowing instantaneous printing. becomes. Vibrator 1
Following near 06, ink flow path 11 and ink tank 10
8 hot melt ink 105B is also sequentially dissolved,
Eventually, the entire inkjet head 101 becomes constant at a predetermined temperature. The vibrator 106 is efficiently and stably vibrated at a high frequency in the direction of the arrow C-D, and the hot melt ink 105A in the liquid phase sucked up by capillary action from the ink flow path 111 is pressurized to form the nozzle of the nozzle forming plate 103. The ink is ejected from the recording paper 104 and attached to the recording paper 104 to form characters, lines, etc.

When the inkjet head 101 ejects and consumes the hot melt ink 105A one after another, the hot melt ink 105B in the ink flow path 111 is supplied near the vibrator 106 due to capillary action. Along with this, the hot melt ink 105B in the ink tank 108 also sequentially moves to the vicinity of the vibrator 106 along the ink flow path 111. The lumpy hot melt ink 105-1 in the container 113 melts from the vicinity of the fins 112 due to heat conduction from the fins 112. As a result of the above, hot melt ink 105A
・The melting order of the hot melt ink 105B and the hot melt ink 105-1 is as follows: near the vibrator 106 → ink flow path 111 → ink tank 108 → hot melt ink 105-1
The order is as follows. When the predetermined printing operation is repeated in this way, the lumpy hot melt ink 105-1 is consumed, and finally the hot melt ink 10 in the ink tank 108
The liquid level of the hot melt ink 5B falls, and an ink end detector (not shown) in the ink tank is activated within 10 days, making it necessary to replenish the bulk hot melt ink 105-1. The bulk hot melt ink 105-1 is replenished into the container 113 by opening and closing the lid 114 manually or by an automatic replenishment mechanism.

[Effects of the Invention] As described above, according to the present invention, the heating element is brought into contact with the nozzle forming plate, particularly the member near the vibrator, and the hot melt ink near the vibrator is melted first during heat conduction. This has the effect that the warm-up time until the vibrator becomes operational can be shortened, resulting in an inkjet head that is easy to use. However, at this point, the entire inkjet head is not at a constant temperature as in the conventional example, but is capable of printing.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view of an embodiment of an inkjet head of the present invention. FIG. 2 is a partial schematic perspective view of an embodiment of the inkjet head of the present invention. 101... Inkjet head 102... Platen 103... Nozzle forming plate 104... Recording paper 105A... Hot melt ink 105B... Hot melt ink 105-1... Bulk hot melt ink 106... Vibrator 107... Spacer A lO3... Ink tank 109... Heating element support plate 110... Heating element 111... Ink channel 112... Fin 113... Container 114... Lid 115... ...Spacer B 116...Axis or above Applicant Seiko Epson Co., Ltd. agent Patent attorney Kizobe Suzuki and 1 other person

Claims (1)

[Scope of Claims] 1) A heating means that uses hot melt ink and changes the phase of the hot melt ink from a solid phase to a liquid phase, a container that stores the hot melt ink in the form of a lump, and a container that stores the hot melt ink in the liquid phase. In an inkjet head that is equipped with a jetting means for jetting melt ink and forms characters, lines, etc. on recording paper, the heating means and the jetting means are brought into contact with each other, and a heat insulating means is provided between the heating means and the container. An inkjet head featuring 2) The inkjet head according to claim 1, wherein the heat insulating means is constituted by an air layer. 3) The inkjet head according to claim 1, wherein the heat insulating means is made of a heat insulating material such as a foam material or a plastic material.