Device to discharge liquid and head driving method

Patent metadata

Field	Value
Publication number	US-9643414-B2
Application number	US-201615245577-A
Country	US
Kind code	B2
Filing date	Aug 24, 2016
Priority date	Sep 8, 2015
Publication date	May 9, 2017
Grant date	May 9, 2017

Abstract

A device to discharge liquid includes a liquid discharging head to discharge the liquid and a drive waveform generating device to generate and output a drive waveform including continuous multiple drive pulses to discharge the liquid from the liquid discharging head that are continuously arranged in chronological order to form a single droplet. The continuous multiple drive pulses include an inflation waveform element to inflate an individual liquid chamber of the liquid discharging head and a contraction waveform element to contract the inflated individual liquid chamber to discharge the liquid. When the wave element between the continuous multiple drive pulses is determined as the holding wave element between pulses, the voltage held by the holding waveform element is higher than the initial voltage of the inflation waveform element of the first drive pulse and the ending voltage of the contraction waveform element of the last drive pulse.

First claim

What is claimed is:

1. A device to discharge liquid comprising:
a liquid discharging head configured to discharge liquid; and
a drive waveform generating device configured to generate and output a drive waveform;
wherein the drive waveform includes continuous multiple drive pulses to discharge the liquid from the liquid discharging head that are continuously arranged in chronological order to discharge the liquid to form a single droplet of the liquid,
wherein the continuous multiple drive pulses include a first inflation waveform element configured to inflate an individual liquid chamber of the liquid discharging head and a first contraction waveform element configured to contract an inflated individual liquid chamber to discharge the liquid, and
wherein when a wave element between the continuous multiple drive pulses is determined as a holding wave element between pulses, of the continuous multiple drive pulses, a voltage held by the holding waveform element between pulses is higher than each one of a first initial voltage of the first inflation waveform element of a first drive pulse in chronological order and a first ending voltage of the first contraction waveform element of a last drive pulse in chronological order.

2. The device according to claim 1 ,
wherein when a characteristic vibration cycle of the individual liquid chamber is determined as Tc, a discharging interval by the continuous multiple drive pulses is within a range of ½×Tc-2×Tc.

3. The device according to claim 1 ,
wherein the first inflation waveform element of the first drive pulse includes an intermediate holding waveform that holds a first predetermined voltage between the first initial voltage and a second ending voltage of the first inflation waveform element for a first predetermined period of time.

4. The device according to claim 3 ,
wherein the first predetermined period of time is not greater than ½ of a total time of a first period of time from the first initial voltage to the first predetermined voltage and a second period of time from the first predetermined voltage to the second ending voltage.

5. The device according to claim 1 ,
wherein the first contraction waveform element of the last drive pulse includes an intermediate holding waveform that holds a second predetermined voltage between a second initial voltage and the first ending voltage of the first contraction waveform element for a second predetermined period of time.

6. The device according to claim 1 ,
wherein the drive waveform includes a first vibration suppressing pulse having a second contraction waveform element to contract the individual liquid chamber without discharging the liquid after the last drive pulse in chronological order and
wherein when a characteristic vibration cycle of the individual liquid chamber is determined as Tc, a first period of time from an initial point of the first contraction waveform element of the last drive pulse to a first end point of the second contraction waveform element of the first vibration suppressing pulse is within a range of ½×Tc-2×Tc.

7. The device according to claim 1 ,
wherein the drive waveform includes a second vibration suppressing pulse having a second inflation waveform element to inflate the individual liquid chamber after the last drive pulse in chronological order and
wherein when a characteristic vibration cycle of the individual liquid chamber is determined as Tc, a second period of time from an initial point of the first contraction waveform element of the last drive pulse to a second end point of the second inflation waveform element of the second vibration suppressing pulse is within a range of ½×Tc-2×Tc.

8. The device according to claim 1 ,
wherein a drive pulse to discharge the liquid is arranged at least before or after the continuous multiple drive pulses in chronological order in the drive waveform.

9. A head driving method comprising:
generating and outputting a drive waveform including continuous multiple drive pulses that are continuously arranged in chronological order to discharge the liquid to form a single droplet of the liquid; and
applying the continuous multiple drive pulses to a liquid discharging head to discharge liquid therefrom,
wherein the continuous multiple drive pulses includes a first inflation waveform element configured to inflate an individual liquid chamber of the liquid discharging head and a first contraction waveform element configured to contract the individual liquid chamber which is inflated to discharge the liquid, and
wherein when a wave element between the continuous multiple drive pulses is determined as a holding wave element between pulses, of the continuous multiple drive pulses, a voltage held by the holding waveform element between pulses is higher than each one of a first initial voltage of the first inflation waveform element of a first drive pulse in chronological order and a first ending voltage of the first contraction waveform element of a last drive pulse in chronological order.

Assignees

• Sohgawa Norimasa
• Araki Satomi
• OSANAI Shinichiroh
• Ricoh Co Ltd

Inventors

• Sohgawa Norimasa
• Araki Satomi
• OSANAI Shinichiroh

Classifications

• B41J2/155

  for line printing · CPC title

• B41J2/14201

  Structure of print heads with piezoelectric elements · CPC title

• B41J2/14274

  of stacked structure type, deformed by compression/extension and disposed on a diaphragm · CPC title

• B41J2/04588 Primary

  using a specific waveform · CPC title

• B41J2/04581

  controlling heads based on piezoelectric elements · CPC title