Electrically-chargeable element control device, liquid ejection device, and method for controlling electrically-chargeable element

• US 20070046703A1
• Filed: 08/30/2006
• Published: 03/01/2007
• Est. Priority Date: 08/31/2005
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Tamura, Noboru
• Granted Patent: US 7,686,408 B2
• Time in Patent Office: Days
• US Class Current: 347/9
• CPC Class Codes: B41J 2/04541 Specific driving circuit
• CPC Class Codes: B41J 2/04581 controlling heads based on piezoelectric elements
• CPC Class Codes: B41J 2/04588 using a specific waveform

Abstract

An electrically-chargeable element control device includes a plurality of coils, a switch circuit, and a controller. One end of each of a plurality of the coils is connected to a power supply. The switch circuit is connected to an other end of each of a plurality of the coils and is connected to one electrode provided on each of a plurality of electrically-chargeable elements. The controller connects a selected coil to an electrically-chargeable element to be charged and discharged by controlling the switch circuit depending on the number of the electrically-chargeable elements to be charged and discharged, and charges and discharges with resonance the electrically-chargeable element to be charged and discharged.

Claims

1. An electrically-chargeable element control device, comprising:

(a) a plurality of coils whose respective one ends are connected to a power supply;

(b) a switch circuit that is connected to an other end of each of a plurality of the coils, and that is connected to one electrode provided on each of a plurality of electrically-chargeable elements; and

(c) a controller that causes a selected coil to connect to an electrically-chargeable element to be charged and discharged by controlling the switch circuit depending on the number of the electrically-chargeable elements to be charged and discharged, and that causes to charge and discharge with resonance the electrically-chargeable element to be charged and discharged.

2. An electrically-chargeable element control device according to claim 1, wherein:

a plurality of the coils include;

a reference coil having a largest inductance; and

an other coil whose inductance is determined to decrease by a ratio of 1/2ⁿ (n is a natural number) with respect to the inductance of the reference coil; and

the controller determines

a selection manner of the reference coil and the other coil depending on the number of the electrically-chargeable elements to be charged and discharged.

3. An electrically-chargeable element control device according to claim 2, wherein:

the controller causes a binary counter to count the number of the electrically-chargeable elements to be charged and discharged, and controls the switch circuit depending on a counted value obtained.

4. An electrically-chargeable element control device according to claim 1, wherein:

the switch circuit includes;

a first switch group for connecting selectively a plurality of the coils; and

a second switch group for connecting selectively a plurality of the electrically-chargeable elements; and

the controller

causes to obtain the number of the electrically-chargeable elements to be charged and discharged according to control information for the second switch group, and controls the first switch group.

5. An electrically-chargeable element control device according to claim 4, including:

an other switch circuit for equalizing the electric potential between the one electrode and an other electrode that are provided on the electrically-chargeable element.

6. An electrically-chargeable element control device according to claim 1, wherein:

the electrically-chargeable element is configured by a piezo element that is deformed by charging and discharging.

7. An electrically-chargeable element control device according to claim 1, including:

an other electrically-chargeable element that is connected in parallel with a plurality of the electrically-chargeable elements and that is charged and discharged regardless of the presence or absence of the electrically-chargeable element to be charged and discharged.

8. An electrically-chargeable element control device according to claim 7, wherein:

the other electrically-chargeable element is configured by a capacitor.

9. An electrically-chargeable element control device, comprising:

a plurality of coils whose respective one ends are connected to a power supply, a plurality of the coils including;

a reference coil having a largest inductance; and

an other coil whose inductance is determined to decrease by a ratio of 1/2ⁿ (n is a natural number) with respect to the inductance of the reference coil;

a switch circuit that is connected to an other end of each of a plurality of the coils, and that is connected to one electrode provided on each of a plurality of electrically-chargeable elements configured by a piezo element that is deformed by charging and discharging, the switch circuit including;

a first switch group for connecting selectively a plurality of the coils; and

a second switch group for connecting selectively a plurality of the electrically-chargeable elements;

an other switch circuit for equalizing the electric potential between the one electrode and an other electrode that are provided on the electrically-chargeable element;

a controller that;

causes a binary counter to count the number of electrically-chargeable elements to be charged and discharged, according to control information for the second switch group;

controls the first switch group depending on a counted value obtained; and

determines a selection manner of the reference coil and the other coil;

causes a selected coil to connect to the electrically-chargeable element to be charged and discharged; and

causes to charge and discharge with resonance the electrically-chargeable element to be charged and discharged; and

an other electrically-chargeable element that;

is configured by a capacitor, the other electrically-chargeable element

being connected in parallel with a plurality of the electrically-chargeable elements, and

being charged and discharged regardless of the presence or absence of the electrically-chargeable element to be charged and discharged.

10. A liquid ejection device, comprising:

(A) a plurality of coils whose respective one ends are connected to a power supply and whose respective other ends are connected to a switch circuit;

(B) a plurality of electrically-chargeable elements whose respective one ends are connected to the switch circuit, and that are deformed depending on stored electric charge;

(C) a plurality of pressure chambers that are respectively provided corresponding to each of a plurality of the electrically-chargeable elements and that generates fluctuation in the pressure of stored liquid by deformation of the electrically-chargeable element;

(D) a plurality of nozzles that are respectively in communication with each of a plurality of the pressure chambers; and

(E) a controller that causes a selected coil to connect to an electrically-chargeable element that corresponds to the nozzle that is to eject liquid by controlling the switch circuit depending on the number of the nozzles that is to eject liquid, and that causes to eject the liquid from the nozzle that is to eject liquid by causing to charge and discharge with resonance the electrically-chargeable element corresponding to the nozzle.

11. A method for controlling an electrically-chargeable element, comprising:

obtaining the number of electrically-chargeable elements to be charged and discharged from among a plurality of electrically-chargeable elements;

selecting a coil to be connected, from among a plurality of coils whose respective one ends are connected to a power supply, depending on the number of the electrically-chargeable elements to be charged and discharged; and

connecting the selected coil to the electrically-chargeable element to be charged and discharged, and charging and discharging with resonance the electrically-chargeable element to be charged and discharged.