JPH0447945A - Inkjet recording device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an inkjet recording device, and particularly to a support device for a nozzle gun that ejects ink particles.

[Conventional technology]

A conventional nozzle gun support device for an inkjet recording apparatus is as described in Tokuhara No. 10484/1984.

The nozzle gun is supported within a case for holding the nozzle gun via O-rings at both ends thereof so that the nozzle gun can move freely in the axial direction in response to the excitation of the piezoelectric element.

However, due to the structure in which both ends of the nozzle gun are supported via O-rings, the ink droplet ejecting end of the nozzle gun can also move in the axial direction and the perpendicular direction. No consideration was given to vibrations in the right angle direction.

[Problem to be solved by the invention]

The above conventional technology has a structure in which both ends of the nozzle gun are supported via O-rings, so the ink droplet ejecting end of the nozzle gun can also move in the axial direction and perpendicular direction, and ink droplets are ejected in response to excitation of the piezoelectric element. There is a problem in that the end vibrates also in the direction perpendicular to the axial direction, which changes the state of ink droplet formation.

The purpose of the present invention is to eliminate the drawbacks of the prior art as described above,
Suppresses vibrations in the axial and perpendicular directions of the ink droplet ejection end,
The object of the present invention is to enable stable generation of ink particles, and also to provide a more reliable inkjet recording device in consideration of ease of assembly.

[Means to solve the problem]

The above purpose is to support the ink droplet ejecting end of the nozzle gun so that it can move in the axial direction due to the vibration of the piezoelectric element, and also to suppress movement in the direction perpendicular to the axial direction, or by using a support member. This is achieved by support and the configuration of the support member which makes the above-mentioned problems possible.

Further, in order to improve the ease of assembling the nozzle gun, a protective stopper is provided on the support member to facilitate positioning of the support member during assembly.

[Effect]

The ink droplet ejecting end of the nozzle gun vibrates not only in the axial direction but also in the direction perpendicular to the axial direction due to the vibration of the piezoelectric element. Because it is supported so that movement can be suppressed,
The ink droplet ejection end vibrates almost only in the axial direction. Therefore, it is possible to prevent an adverse effect on the state of ink droplet production due to vibration of the ink droplet ejection end in the axial direction and the direction perpendicular to the axis, and it is possible to stably generate ink droplets.

Further, since the support member is provided with a protective stopper, the positional relationship between the nozzle gun and the support member is determined, and the ease of assembling the nozzle gun is improved.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3.

FIG. 1 is a schematic diagram showing an embodiment of the apparatus of the present invention, which includes a nozzle gun 2 that generates ink particles 1, a control system that deflects the ink particles 1 ejected from the nozzle gun 2, and a control system that deflects the ink particles 1 ejected from the nozzle gun 2. It consists of an ink circulation system that supplies ink to the ink.

That is, the nozzle gun 2 has an excitation element, for example a piezoelectric element 4, connected to an excitation source 3, and ink particles 1 are ejected from its tip by mechanical vibration of the piezoelectric element 4.

Reference numeral 5 denotes a charging electrode that is arranged at a position where the ink particles 1 are separated from the ink column at the tip of the nozzle gun 2 and is connected to an information signal source 6. The ink particles 1 are charged to have a predetermined charge.

The charged ink particles 1 are connected to a DC power source 7 and passed through deflection electrodes 8 facing each other across the flight path of the ink particles 1.

At this time, the ink particles 1 are deflected by a predetermined amount depending on the amount of charge of each ink particle, and adhere to the recording medium 9.

On the other hand, the ink particles 1 to which no charge has been applied continue straight and are prevented from adhering to the recording medium 9 by the gutter 10.

Furthermore, 11 is the ink stored in the ink tank 12,
The ink 11 is supplied to the pump 13. Filter 14 and adjustment 1
115 to the nozzle gun 2, and the gutter 1
The ink 11 blocked by the ink is circulated to the ink tank 12 via a filter 16 and a pump 17.

In the apparatus of the present invention configured as described above, ink 11 is pumped from an ink tank 12 to a filter 14 by a pump 13. It is supplied under pressure to the nozzle gun 2 through the regulator 15.

This pressurized ink 11 is ejected from a nozzle gun 2 and becomes regular ink particles 1 by an excitation source 3 applied to a piezoelectric element 4 of the nozzle gun 2.

The ink particles 1 are charged with a charge according to the character signal by the charging electrode 5, are deflected by the electrostatic field in the deflection electrode 8, jump over the gutter 10, and collide on the recording medium 9.

By moving this recording medium 9 in a direction perpendicular to the deflection direction of the ink particles 1, a printed dot matrix is formed on the recording medium 9.

On the other hand, ink particles 1 (charged electrode 5) that were not used for printing
Ink particles that are not given a charge when passing through 1)
travels straight without being deflected by the deflection electrode 8, collides with the gutter 10, and is pumped into the ink tank 12 by the pump 17.
will be collected.

The nozzle gun 2 used in the above-mentioned inkjet recording apparatus will be explained with reference to FIGS. 2 and 3. The nozzle gun 2 includes a vibrator 2o in which a jewel orifice is housed at the tip thereof, and a piezoelectric element press-fitted into the pipe 20. 4 and a lock nut 22 for fixing the piezoelectric element 4 and the terminal 21.

Furthermore, the terminal 21 is connected to the excitation source 3 via a lead wire 23 so that the piezoelectric element 4 is vibrated at a predetermined frequency by the excitation source 3.

One end (ink inflow end) of the nozzle gun 2 is fixed to a filter case 27 via an O-ring 24, and the tip of the nozzle gun 2 is fixed to a nozzle gun case 26 via a nozzle tip support member 30. The ink 11 supplied by 28 passes through the filter case 27 and is accurately supplied to the nozzle gun 2 without leaking.

The nozzle tip support member 30 is connected to the housing 31. Pressing housing 32. It is composed of a housing pedestal 33 and a fixing screw 34, and the housing pedestal 33 is attached to the housing 3.
1 and a pressing housing 32, and is fixed to the nozzle gun case 26 with a fixing screw 35.

The tip of the nozzle gun 2 is fixed and supported by a fixing screw 34 to this nozzle tip support member 30.

The nozzle gun case 26 and the filter case 27 are connected by a fixing screw 29, and the filter case 27 and the tube connector 28 are connected by a fixing screw 36.

The nozzle gun 2, cases 26, 27, and nozzle tip support member 3o can be assembled as follows.

First, the lead wire 23 is attached to the nozzle gun case 26 via a bushing, and after the O-ring 24 is fitted into the groove of the filter case 27, the ink inflow end of the nozzle gun 2 is fitted. Furthermore, the nozzle gun case 26 and the filter case 27 are combined, and both are fixed with fixing screws 29.

A nozzle tip support member 3 is attached to the tip of the nozzle gun 2.
After fixing the nozzle gun tip support member 30 to the nozzle gun case 26 with the fixing screw 35 through the nozzle gun mounting hole 0, remove the tip of the nozzle gun 2, being careful not to move the nozzle tip support member 30 in the axial direction Fix the screw 34
Fix it with to finish the assembly.

The ink droplet ejecting end of the nozzle gun 2 configured in this way is vibrated by the piezoelectric element 4 which vibrates at a predetermined frequency by the excitation source 3, but since the tip of the nozzle gun 2 is supported by the nozzle tip support member 30, In the axial direction, the four arms of the housing pedestal 33 of the nozzle tip support member 30 are uniformly elastically deformed, so that they are movable. Further, in the direction perpendicular to the axial direction, the four arms of the housing pedestal 33 prevent the tip of the nozzle gun 2 from moving in the direction perpendicular to the axial direction, so that movement is suppressed. That is, the ink droplet ejection end vibrates almost only in the axial direction. here,
The magnitude of the amplitude of the vibration in the axial direction is determined by the rigidity of the four arms of the housing pedestal 33, and the relationship between the amplitude and the ink droplet creation state is determined by experiment to be 0 or more.
Due to the vibration of the ink droplet ejection end in the axial direction and the direction perpendicular to the
It is possible to prevent an adverse effect on the state of ink particle creation.

According to this embodiment, since the tip of the nozzle gun 2 is not supported via an O-ring, there is no need to provide a deep groove for the O-ring in the nozzle gun case 26, and the processing of the nozzle gun case 26 is facilitated. Even if the cost of parts for the nozzle tip support member 30 is considered, the overall cost can be reduced.

4 and 5 show other embodiments of the present invention, in which the tip of the nozzle gun 2 is supported by a nozzle tip support member S37, and four S-shaped housing pedestals 39 of the nozzle tip support member 837 are axially supported. It is movable because its arms uniformly deform elastically. Furthermore, in the direction perpendicular to the axial direction, the four arms of the S-shaped housing pedestal 39 prevent the tip of the nozzle gun 2 from moving in the direction perpendicular to the axial direction. It will only vibrate. Therefore, this is due to the movement of the ink droplet ejection end in the direction perpendicular to the axial direction. It is possible to prevent an adverse effect on the state of ink particle creation. In addition, since the nozzle tip support member S37 is provided with a pressing housing 38 with a protective stopper, when the nozzle tip support member S37 is assembled into the nozzle gun 2, the nozzle tip support member 837 is attached to the tip of the nozzle gun 2. Insert the nozzle tip support member S37 through the hole until the end of the pressing housing 38 with a protective stopper comes into contact with the upper surface of the flange 40 of the nozzle gun 2, and fix the tip of the nozzle gun 2 with the fixing screw 34. Nozzle tip support member S37
The positional relationship between is determined.

Here, the S-shaped housing pedestal 39 is attached to the nozzle gun case 2.
By determining the dimensions of the pressing housing 38 with a protective stopper so as to be in contact with the upper surface of the nozzle tip support member S for the nozzle gun 2 and the nozzle gun case 26.
The positional relationship of 37 is determined. Therefore, the pressing housing 38 with a protective stopper is attached to the nozzle tip support member S37.
By providing this, the ease of assembling the nozzle gun 2 can be improved.

Further, the arms of the S-shaped housing pedestal 39 of this embodiment are in an inverted S-shape, and can be longer than the linear arms of the housing pedestal 33 of the first embodiment. A larger amount of elastic deformation can be obtained with the same material and the same size (width of the arm).

Therefore, in order to obtain a larger amount of elastic deformation with the housing pedestal 33, the width of the arm must be made thinner, but with the S-shaped housing pedestal 39, the width can be adjusted by adjusting the arm length. is more advantageous in terms of rigidity.

Furthermore, rl=! shown in FIG. 6(c). A similar effect can be obtained by using the (shaped) housing pedestal 40 instead of the S-shaped housing pedestal 39.

〔Effect of the invention〕

According to the present invention, the tip of the nozzle gun (the ink droplet ejecting end) is supported so that it can be moved in the axial direction due to the vibration of the piezoelectric element, and furthermore, the movement in the direction perpendicular to the axial direction can be suppressed. Alternatively, by supporting the ink droplet with a support member, it is possible to prevent an adverse effect on the state of ink droplet production due to vibration of the ink droplet ejection end in a direction perpendicular to the axial direction. In addition, the structure of the support member allows the ink droplet ejection end of the nozzle gun to move in the axial direction due to the vibration of the piezoelectric element, and also suppresses movement in a direction perpendicular to the axial direction. It is possible to prevent an adverse effect on the state of ink droplet creation due to vibration of the droplet ejection end in a direction perpendicular to the axial direction. Furthermore, by providing a protective stopper on the support member, it is possible to easily position the support member when assembling the nozzle gun, and to improve the ease of assembling the nozzle gun. A more reliable inkjet recording device can be provided.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing the configuration of the device of the present invention, FIG. 2 is a sectional view of one embodiment of a nozzle gun used in the device of the present invention, FIG. 3 is a side view thereof, and FIG. FIG. 5 is a side view thereof, and FIG. 6 is a front view of various types of housing bases used in the apparatus of the present invention. DESCRIPTION OF SYMBOLS 1... Ink particle, 2... Nozzle gun, 4... Piezoelectric element, 20... Vibrator, 26... Nozzle gun case, 30... Nozzle tip support member.

Claims (1)

[Scope of Claims] 1. A nozzle gun that generates ink particles from the tip of the ink supplied from the ink tank in synchronization with the vibration cycle of an excitation element, and a predetermined information signal that controls the ink particles ejected from the nozzle gun. In the device that charges the nozzle gun and deflects it to deposit it on the recording medium, one end of the nozzle gun is placed in a case for holding the nozzle gun so that it can be moved in the axial direction by the vibration of the excitation element. , outside the case for holding the nozzle gun, so that the tip of the nozzle gun can be moved in the axial direction by the vibration of the excitation element, and can be prevented from moving in a direction perpendicular to the axial direction. An inkjet recording device characterized in that each of the inkjet recording devices is supported by the following. 2. In claim 1, one end of the nozzle gun held in the case is supported via an O-ring that also serves to prevent leakage, and the tip of the nozzle gun is supported by a support member made of a plate material. An inkjet recording device characterized by being supported. 3. The support member according to claim 2, wherein the tip of the nozzle gun is made movable in the axial direction and restrained from moving in a direction perpendicular to the axial direction. 4. The support member according to claim 2 or 3, characterized in that it is provided with a protective stopper.