JPH03224744A - Pressure absorption device of ink jet recording device - Google Patents

Abstract

PURPOSE:To increase a pressure absorption capacity and thereby obtain a compact, highly reliable damper by providing a pressure absorption chamber on three surfaces, then integrating a damper base and an ink feed preparation chamber in a single piece and mounting a damper diagonally to a horizontal surface. CONSTITUTION:A head 2 is fixed to a metal holder 21 for fastening the head 2 to an enclosure case. In addition, a separate reservoir which is an ink feed preparation chamber for feeding ink to the head 2 is fixed to the head 2 through a rubber packing 24 using a fastening spring 22 and a screw 23. A damper consists of a pressure absorption surface which absorbs pressure and integrated with the separate reservoir 4 which is the ink feed preparation chamber for feeding ink to the head. In addition, the head 2 on which the damper 6 is mounted is assembled in the enclosure case 25 and then is attached to a carriage 31, and the carriage 31 is installed diagonally by an angle theta. Thus the pressure absorption amount can be increased by installing the damper diagonally to a horizontal surface.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a device (hereinafter referred to as a damper) that absorbs ink pressure generated by acceleration of a carriage of an inkjet recording device.

[Summary of the Invention] The present invention provides a damper that absorbs ink pressure generated by acceleration of a carriage of an inkjet recording device, in which pressure absorption chambers are provided on three sides, a damper base and an ink supply preparation chamber are integrated, and the damper is further provided with pressure absorption chambers on three sides. By installing the damper at an angle with respect to the horizontal plane, a compact and highly reliable damper can be created.

[Prior Art] In an inkjet recording apparatus, when a carriage moves, a pressure is generated in a flow path that is proportional to the product of the acceleration of the carriage, the length of the flow path from the ink tank to the head, and the specific gravity of the ink.

If this pressure is directly transmitted to the nozzles of the recording head, the ink droplets will change, resulting in irregular printing, and if the ink droplets scatter, printing defects such as missing dots will occur. Conventionally, two methods have been taken to deal with this problem. One method is to arrange the flow path perpendicular to the moving direction of the carriage, and the other method is to provide a damper in the middle of the flow path leading to the recording head.

A conventional damper consists of a damper base and a flexible damper film. The damper base is provided with an ink inlet port connected to the supply pipe and an ink outlet port connected to the supply pipe, and a smooth shape connecting the ink inlet port and the ink outlet port is provided on one or both sides of the damper base. A flow path and a damper hole branched from the flow path are formed, and a member (spring, net, etc.) for suppressing deflection of the damper film is arranged at a position opposite to the damper hole, and a flexible film is formed so as to cover the damper hole. The damper film was heat-sealed to the damper base. Also, Fig. 4 (a), (b), (c)
As shown in FIGS. 5(a) and 5(b), the conventional damper and head have a plastic or metal supply port 13 fixed to the head 2 by adhesive or the like, and a damper 6 fixed to the damper 6 by adhesive or the like. A tube 4.5 made of polyethylene, two layers of nylon/polyethylene, or the like is press-fitted into the outlet port 10 made of plastic or metal. Further, the head 2 is fixed to a metal holder 21 for fixing the head 2 to an exterior case.
1, a separate reservoir 4 for ink supply is attached to the gasket 24.
A ring 26 was fitted into the reservoir supply port 13, and was press-fitted into the damper outlet 1o. As a result, fatigue cracks occurred at the joints due to the combination of materials for the supply port, outlet port, and supply pipe, resulting in poor printing and ink supply.

[Problems to be Solved by the Invention] However, in the above-mentioned prior art, if the area of the pressure absorption chamber is reduced due to the structure of the damper, the pressure absorption capacity may be reduced.
In addition, conventional head and damper installation involves a supply pipe made of a laminated tube of polyethylene, nylon, and polyethylene, a hard plastic or metal ink supply port provided on the head side, and a plastic or metal ink supply port provided on the damper. In the past, the hard plastic or metal supply port on the separate reservoir side was press-fitted into the plastic outlet port on the damper side. This has caused problems such as fatigue cracking, resulting in poor printing and an inability to supply ink. The present invention is intended to solve these problems, and its purpose is to provide a compact and highly reliable damper.

[Means for Solving the Problems] The pressure absorption device (damper) in the inkjet recording apparatus of the present invention has the following features: (1) The structure of the damper base is made three-dimensional, pressure absorption chambers are provided on three sides of the damper base, and pressure absorption chambers are provided on three sides of the damper base. (2) The damper base and the ink supply preparation chamber are integrated. (3) The pressure absorption device is installed tilted with respect to the horizontal plane. Features.

[Embodiment] Figures 1 and 2 show an embodiment of the present invention, in which Figure 1 is an exploded perspective view, Figure 2 (a) is a front view, Figure 2 (b) is a top view, and Figure 2 (b) is a top view. Figure 2 (C) is a rear view.

A damper 6 is provided between an inkjet head 2 having a nozzle 1 for ejecting ink droplets and a supply pipe 4 guiding ink from an ink tank 3 to the head 2. The damper 6 moves in synchronization with the reciprocating movement of the head 2 in the direction of arrow A.

The damper 6 is composed of a damper base 7 and a flexible damper film 8. Inlet ports 9a, 9b, 9c connected to the supply pipe 4 and outlet ports 10a, 10b, 10c connected to the head 2 are formed as through holes in the damper base 7. Smooth channels 12a, 12b, 12c connecting inlets 9a, 9b, 9c and outlets 10a, 10b, 10c, damper holes 11a, llb, llc branching from the channels, each having three sides. It is formed as a groove. In addition, each surface °C flow path 12a, 12b,
12c are connected to each other. The damper base 7 has a damper film 8 made of flexible polyethylene or a laminated film of polyethylene and nylon so as to cover the damper holes 11a, llb, and 11c on each side.
It is sealed by heat-sealing it to the damper base 7.

When the inkjet head 2 and the damper 6 are in a stationary state, the flow paths 12a, 12b, and 12c leading to the damper holes 11a, llb, and 11C are filled with ink halfway, and the head and damper are mounted on the carriage as described above. When reciprocating, a pressure F as shown in equation 1 is generated in the flow path.

F-to・V-L・ρ...Formula I V...Acceleration L of the carriage in the flow path...
Length of the flow path from the ink tank to the head ρ... Specific gravity of the ink... Proportionality constant This pressure F is absorbed by the compression of the air in the damper holes lla, llb, 11c and the deflection of the damper film 8. . In conventional single-sided and double-sided dampers, if the area of the damper hole is increased in order to increase the pressure absorption capacity, the damper itself must be made larger, and the damper is larger than the head. Compared to conventional dampers, the damper of the present invention has a length of 1/2 due to the fact that the damper hole is formed on three three-dimensional surfaces.
It can be reduced to ~2/3.

FIG. 3(a) is an exploded perspective view showing one embodiment of the present invention, and FIG. 3(b) is a sectional view showing the attachment of the damper and head of the present invention. Figure 4 (a), (b), (c), 5th
Figures (a) and (b) are sectional views and detailed views showing the attachment of a conventional damper and head.

In FIG. 3, the head 2 is fixed to a metal holder 21 for fixing the head 2 to an exterior case. A separate reservoir 4, which is an ink supply preparation chamber for supplying ink to the head 2, is fixed to the holder 21 with a fixing spring 22 and screws 23 via a rubber gasket 24.

The damper of the present invention is integrally formed with a pressure absorption surface that absorbs pressure and a separate reservoir 4 of an ink supply preparation chamber that supplies ink to the head. In contrast, conventional dampers and heads have a plastic or metal supply port 13 fixed to the head 2 with adhesive or the like, and a plastic or metal outlet 1 fixed to the damper 6 with adhesive or the like.
It was attached by press-fitting a tube 4.5 made of polyethylene, two layers of nylon/polyethylene, etc. Further, the head 2 is fixed to a metal holder 21 for fixing the head 2 to an exterior case.
1, a separate reservoir 4 for ink supply is attached to the gasket 24.
An O-ring 26 is fitted to the reservoir supply port 13, and the damper outlet 1
It was attached by press fitting to 0. For this reason, fatigue cracks occur in the joints due to the material combination of the supply port, outlet port, and supply pipe, resulting in poor printing and ink supply.However, in the damper of the present invention, the supply pipe and joints connecting the head and damper This eliminates the need for an ink supply system, making the ink supply system more compact.

Furthermore, since a press-fitting method is not used for installation, there is no risk of fatigue cracking, and problems such as poor printing and ink supply can be suppressed.

An embodiment will be shown in which the pressure absorption capacity of the damper is increased. As shown in FIG. 6, the head 2 with the damper 6 attached thereto is assembled in an exterior case 25 and attached to a carriage 31. Carriage 3 with head attached
1 is attached at an angle of θ with respect to the horizontal plane.

Conventional dampers are mounted perpendicular to the horizontal plane, which requires a large pressure absorption chamber. The damper of the present invention can increase its pressure absorption capacity by mounting the damper at an angle with respect to the horizontal plane. Here, it is preferable that the mounting angle θ is about 5 to 85 degrees.

[Effects of the Invention] As described above, according to the present invention, the pressure absorption chambers are provided on three sides, the damper and the ink supply preparation chamber are integrated, and the damper is mounted at an angle with respect to the horizontal plane.
A compact and highly reliable damper can be realized. Furthermore, by using this damper to create a compact head/socket, it is possible to downsize the recording device.

[Brief explanation of drawings]

FIG. 1 is an exploded perspective view showing an embodiment of the pressure absorbing device of the present invention. FIGS. 2(a), (b), and (c) are a front view, a top view, and a rear view of the embodiment shown in FIG. 1, respectively. FIGS. 3(a) and 3(b) are an exploded perspective view and a sectional view showing the attachment of the pressure absorbing device of the present invention and the head. FIGS. 4(a), 4(b), and 4(c) are a sectional view and a detailed view showing attachment to a conventional head, respectively. FIGS. 5(a) and 5(b) are a sectional view and a detailed view, respectively, showing attachment to a conventional head. FIG. 6 is a diagram showing a method of fixing the head for the purpose of increasing the pressure absorption capacity of the pressure absorption device of the present invention. 1a 1b 1 C Damper Damper base Damper film Damper hole Damper hole Damper hole Figure 2 Nozzle (a) Figure 3 (b) Figure 3 Figure 4 (b) Figure 5 Figure 6

Claims (3)

[Claims] (1) The pressure of an inkjet recording device consisting of a pressure-absorbing substrate and a flexible pressure-absorbing film that moves in synchronization with a recording head that performs recording by reciprocating in a direction across the recording paper while ejecting ink droplets from a nozzle. An ink jet recording characterized in that, in the absorption device, the pressure absorption substrate is provided with an ink inlet, an ink outlet, a flow path from the ink inlet to the outlet, and a pressure absorption chamber branched from the flow path on three sides. Equipment pressure absorption device. (2) The pressure absorbing device for an inkjet recording apparatus according to claim 1, wherein the pressure absorbing substrate and an ink supply preparation chamber for supplying ink to the recording head are integrally formed. (3) The pressure absorption device for an inkjet recording apparatus according to claim 1, wherein the pressure absorption device is installed at an angle with respect to a horizontal plane.