Patent Description:
Liquid ejection heads, such as inkjet heads, can be used in various liquid ejection devices. A liquid ejection head includes, for example, an actuator formed of a piezoelectric material that changes the pressure in a pressure chamber to eject a liquid, such as ink, from the pressure chamber. The liquid ejection head ejects liquid from a nozzle by operation of the actuator.

For example, Document <CIT> discloses a liquid ejecting head including a liquid channel having a pressure generating chamber communicated with a nozzle opening that ejects liquid, and a first liquid chamber installed at one end of the pressure generating chamber to communicate a plurality of pressure generating chambers; a pressure generating unit for changing pressure in the pressure generating chamber so that liquid is discharged from the nozzle opening; a heating unit for heating liquid in the liquid channel at an upstream of the pressure generating chamber; a second liquid chamber installed at the other end of the pressure generating chamber; and a circulating channel formed among a pressure generating chamber group having at least one pressure generating chamber to connect the first liquid chamber and the second liquid chamber.

In recent years, the printing rate and printing speed of certain liquid ejection devices have been increasing. Therefore, the amount of heat generated in the pressure chamber of the liquid ejection head tends to increase. When the temperature of the pressure chamber rises, the temperature of the ink also increases, and thus the viscosity and other physical properties of the ink may change, which may affect printing. Heating of the ink (or other liquid) may cause the ink (or other liquid) to heat. It may be possible to cool the ink if the liquid ejection head is a circulating type liquid ejection head that circulates ink in and out of the head, but it is generally difficult to cool the ink if the liquid ejection head is a non-circulating type.

An object to be solved by an exemplary embodiment is to provide a liquid ejection head and a liquid ejection device capable of controlling the temperature of the ejected liquid.

In general, according to one embodiment, a liquid ejection head as defined in claim <NUM> is provided. Preferred embodiments of the liquid ejection head are defined in dependent claims.

Preferably, the temperature control liquid of the liquid ejection head may be water.

There is also provided a liquid ejection device, comprising a liquid feed pipe connectable to a storage tank, and the liquid ejection head described above. The liquid surface side of the manifold, the liquid discharge port and the liquid supply port being on a first longitudinal end portion of the lower surface side of the manifold; a first temperature control pipe connected to the temperature control flow path via a first temperature control port on the first longitudinal end portion of the lower surface side of the manifold; and a second temperature control pipe connected to the temperature control flow path via a second temperature control port on a second longitudinal end portion of the lower surface side of the manifold, the second longitudinal end portion and the first longitudinal end portion being at opposite longitudinal ends of the manifold.

Preferably, the actuator comprises piezoelectric material, and the piezoelectric material forms sidewalls of each of the pressure chambers.

Preferably, the liquid ejection head further comprises a frame member on the upper surface side of the base plate. The frame member surrounds the actuator, the first common chamber, and the second common chamber, and the nozzle plate is affixed to the frame member.

Preferably, the base plate is directly attached to the manifold.

Preferably, the liquid supply flow path comprises a first groove formed in the lower surface side of the manifold, and the liquid discharge flow path comprises a second groove formed in the lower surface side of the manifold.

Preferably, the liquid ejection head further comprises a top plate fixed to the lower surface side of the manifold.

Preferably, the supply hole is an elongated shape extending in a longitudinal direction of the base plate.

Preferably, the first common chamber is between a pair of actuators on the upper surface side of the base plate.

Preferably, the liquid feed port comprises a liquid feed hole through the top plate and a first base block fixed to the top plate, and the liquid discharge port comprises a liquid discharge hole through the top plate and a second base block fixed to the top plate.

Preferably, the temperature control liquid may be water.

There is also provided a liquid ejection device, comprising a liquid feed pipe connectable to a storage tank, and the liquid ejection head described above. The liquid ejection head is connected to the liquid feed pipe.

Preferably, the liquid ejection device further comprises a support facing the nozzle plate, the support configured to support an object while liquid is ejected from the liquid ejection head towards the object.

Preferably, the liquid feed pipe may be connected to the liquid supply port.

Preferably, the liquid discharge pipe may be connected to the supply tank.

Preferably, the liquid ejection device further comprises a temperature control device configured to detect and adjust a temperature of the temperature control liquid.

Hereinafter, a liquid ejection head according to certain example embodiments will be described with reference to the drawings. The drawings are not necessarily to scale and various changes, modifications, and alterations to the depicted aspects may be made without departing from the scope of the present disclosure.

<FIG> is a perspective view illustrating a configuration of the liquid ejection head <NUM>. <FIG> is a perspective view illustrating a head body <NUM> and a manifold unit <NUM> of the liquid ejection head <NUM>. <FIG> is a cross-sectional view illustrating aspects of the configuration of the head body <NUM> and the manifold unit <NUM>. <FIG> is a plan view of the head body <NUM>. <FIG> and <FIG> are perspective views of the manifold unit <NUM>. <FIG> and <FIG> are views of the manifold unit <NUM> illustrated from different directions.

The liquid ejection head <NUM> is, for example, an ink jet head in a liquid ejection device <NUM>. The liquid ejection device <NUM> may be an ink jet recording device such as illustrated in <FIG>. The liquid ejection head <NUM> is provided in a head unit <NUM>. The head unit <NUM> includes a supply tank <NUM> for storing a liquid in the liquid ejection device <NUM>.

The liquid ejection head <NUM> is supplied with ink from the supply tank <NUM>. The liquid ejection head <NUM> may be a circulating type head that circulates ink, or may be a non-circulating type head that does not circulate ink. In the present example, the liquid ejection head <NUM> will be described as a non-circulating type head. The liquid ejection head <NUM> is connected to a temperature control device <NUM> provided in the liquid ejection device <NUM>. A temperature control liquid for controlling the temperature of the ink can be supplied. The temperature control liquid may be water, for example.

The liquid ejection head <NUM> illustrated in <FIG> includes a head body <NUM>, a manifold unit <NUM>, and a circuit board <NUM>. In some examples, the liquid ejection head <NUM> may include a cover for accommodating at least part of the head body <NUM>, the manifold unit <NUM>, and the circuit board <NUM>.

The head body <NUM> ejects a liquid. The head body <NUM> includes a base plate <NUM>, a frame <NUM>, an actuator <NUM> having a plurality of first pressure chambers <NUM> and a plurality of second pressure chambers <NUM>, and a nozzle plate <NUM>.

The head body <NUM> includes a first common liquid chamber <NUM> that communicates with the primary side of the first pressure chambers <NUM> of the actuator <NUM> and a second common liquid chamber <NUM> that communicates with the secondary side of the first pressure chambers <NUM> and the primary side of the second pressure chambers <NUM> (see <FIG>). The head body <NUM> also includes a third common liquid chamber <NUM> that communicates with the secondary side of the second pressure chambers <NUM>. The primary side of the first pressure chambers <NUM> is the upstream side with respect to the direction in which the liquid flows through the head body in normal operation. The secondary side of the first pressure chambers <NUM> is the downstream side. The primary side of the second pressure chambers <NUM> is the upstream side. The secondary side of the plurality of second pressure chambers <NUM> is the downstream side.

In the present embodiment, the head body <NUM> includes a pair of actuators <NUM>, one first common liquid chamber <NUM> between the pair of actuators <NUM>, a pair of second common liquid chambers <NUM> (one on each side of the pair of actuators <NUM>), and a pair of third common liquid chambers <NUM> (one on each end of the pair of actuators <NUM>).

The base plate <NUM> is formed in a square plate shape of, for example, a ceramic material. The base plate <NUM> includes one or more supply holes <NUM> and one or more discharge holes <NUM>. The supply hole(s) <NUM> and the discharge hole(s) <NUM> are through holes penetrating the base plate <NUM>.

A supply hole <NUM> is provided, for example, at a position facing the first common liquid chamber <NUM>. The supply hole <NUM> is, for example, an elongated hole or slot with its long dimension along the longitudinal direction of the first common liquid chamber <NUM>.

A discharge hole <NUM> is provided, for example, at positions facing each third common liquid chamber <NUM>. The discharge hole <NUM> is provided in the base plate <NUM> adjacent to second pressure chambers <NUM> at each end of the base plate <NUM>.

The frame <NUM> is fixed to one side of the base plate <NUM> with an adhesive or the like. The frame <NUM> surrounds the supply hole <NUM>, the discharge holes <NUM>, and the actuators <NUM> on the base plate <NUM>.

For example, the frame <NUM> is formed in a rectangular frame shape. The actuators <NUM>, the supply hole <NUM>, and the discharge holes <NUM> are positioned to be inside the opening of the frame <NUM>.

Each actuator <NUM> is formed in a plate shape. Each actuator <NUM> is disposed in the opening of the frame <NUM> and adhered to the base plate <NUM>. The actuators <NUM> comprise rectangular plate-shaped piezoelectric materials adhered to each other so as to face each other with the polarization directions thereof opposite to each other.

In this context, the piezoelectric material is, for example, lead zirconate titanate (PZT). Each actuator <NUM> has a plurality of first pressure chambers <NUM> disposed at equal intervals along the length direction of the base plate <NUM>. The first pressure chambers <NUM> are disposed in two rows on each side of the centerline of the base plate <NUM>. Each actuator <NUM> also has a plurality of second pressure chambers <NUM> disposed at both ends of the base plate <NUM>. The second pressure chambers <NUM> at each end are at equal intervals and in two rows on both sides of the centerline of the baseplate <NUM> like the first pressure chambers <NUM>. Each actuator <NUM> can be said to have a plurality of grooves formed on the main surface side opposite to the base plate <NUM> side. The first pressure chambers <NUM> and the second pressure chambers <NUM> are formed in these grooves. Further, each actuator <NUM> is formed in conjunction with a wiring pattern for driving each pressure chamber <NUM>.

A first pressure chamber <NUM> used as a pressure chamber for ejecting ink from a corresponding nozzle <NUM> during printing or the like. A second pressure chamber <NUM> is a maintenance pressure chamber used for ejecting ink from a nozzle <NUM> during a maintenance operation.

The nozzle plate <NUM> is a plate shape. The nozzle plate <NUM> is fixed to the frame <NUM> with an adhesive or the like. The nozzle plate <NUM> has a plurality of nozzles <NUM> formed at positions facing the first pressure chambers <NUM> and the second pressure chambers <NUM>. In the present embodiment, the nozzle plate <NUM> includes two nozzle rows <NUM> each with a plurality nozzles <NUM> arranged in a line.

Among the plurality of nozzles <NUM>, the those facing the plurality of first pressure chambers <NUM> are holes for ejecting ink during printing operations or the like. Among the plurality of nozzles <NUM>, the those facing the plurality of second pressure chambers <NUM> are holes used for purging ink during maintenance operations or the like.

The first common liquid chamber <NUM> is formed between the facing pair of actuators <NUM>. The first common liquid chamber <NUM> does not extend all the way to the ends of the actuators <NUM>. The first common liquid chamber <NUM> forms an ink flow path from the supply hole <NUM> to the primary (entrance) side of the plurality of first pressure chambers <NUM> of each actuator <NUM>.

A second common liquid chamber <NUM> is formed to be between the frame <NUM> and the outside of each actuator <NUM>. The second common liquid chamber <NUM> forms an ink flow path from the secondary (exit) side of the plurality of first pressure chambers <NUM> to the primary side of some of the plurality of second pressure chambers <NUM>.

The third common liquid chamber <NUM> is separated from the first common liquid chamber <NUM> by, for example, a partition wall <NUM>. A third common liquid chamber <NUM> is formed between the end portions of the pair of actuators <NUM>, and forms an ink flow path from the secondary (exit) side of the second pressure chambers <NUM> at each end of actuators <NUM> to a discharge hole <NUM>.

The manifold unit <NUM> includes a manifold <NUM>, a top plate <NUM>, an ink supply pipe <NUM>, an ink discharge pipe <NUM>, a temperature control water supply pipe <NUM>, a temperature control water discharge pipe <NUM>, and a base block <NUM>. The number of ink supply pipes <NUM> (alternatively, liquid supply pipes <NUM> when a liquid other than ink is utilized), ink discharge pipes <NUM> (alternatively, liquid discharge pipes <NUM> when a liquid other than ink is utilized), temperature control water supply pipes <NUM>, and temperature control water discharge pipes <NUM> can be arbitrarily set.

In the present embodiment, the manifold unit <NUM> includes one ink supply pipe <NUM>, one ink discharge pipe <NUM>, one temperature control water supply pipe <NUM>, and one temperature control water discharge pipe <NUM>, but other examples may vary in these numbers.

As illustrated in <FIG> and <FIG>, the manifold <NUM> can be formed in a plate shape or a block shape. The manifold <NUM> includes an ink supply flow path <NUM> (liquid supply flow path), an ink discharge flow path <NUM> (liquid discharge flow path), and a temperature control flow path <NUM>. One side of the manifold <NUM> is fixed to the base plate <NUM>. The ink supply pipe <NUM>, the ink discharge pipe <NUM>, the temperature control water supply pipe <NUM>, and the temperature control water discharge pipe <NUM> are attached to the manifold <NUM> via the base block(s) <NUM> (<FIG>).

The ink supply flow path <NUM> is formed in the manifold <NUM> as holes and grooves. The ink supply flow path <NUM> fluidly connects the ink supply pipe <NUM> and the supply hole <NUM> of the base plate <NUM>.

The ink supply flow path <NUM> includes an ink supply opening <NUM> (<FIG>) that is longer in one direction. The ink supply opening <NUM> is provided in the surface of the manifold <NUM> to which the base plate <NUM> is fixed. The ink supply opening <NUM> matches in position to the region provided with the supply hole <NUM> disposed in the first common liquid chamber <NUM>.

In the present embodiment, the ink supply flow path <NUM> extends in the longitudinal direction from the ink supply point (where ink is supplied from the ink supply pipe <NUM>) in one branch towards the center of the manifold <NUM>. A portion of the ink supply flow path <NUM> then extends in the lateral (width) direction of the manifold <NUM> to connect to a slit that extends along the longitudinal direction of the first common liquid chamber <NUM> in the center of the manifold <NUM>. This central slit can be considered as a portion of the ink supply flow path <NUM>. The base plate <NUM> side end of this slit forms the ink supply opening <NUM>.

The ink discharge flow path <NUM> is a flow path formed in the manifold <NUM> by holes and grooves. The ink discharge flow path <NUM> fluidly connects the ink discharge pipe <NUM> and the discharge holes <NUM>.

The ink discharge flow path <NUM> includes two ink discharge openings <NUM> (see <FIG>) on the surface of the manifold <NUM> to which the base plate <NUM> is fixed. The two ink discharge openings <NUM> match each of the regions provided with the discharge holes <NUM>. A discharge hole <NUM> is disposed in correspondence with each of the third common liquid chambers <NUM>, respectively. In the ink discharge flow path <NUM>, the two ink discharge openings <NUM> communicate with each other by a groove in the surface of the manifold <NUM> opposite from that to which the base plate <NUM> is fixed.

The temperature control flow path <NUM> is a flow path formed in the manifold <NUM> by holes and grooves. The temperature control flow path <NUM> fluidly connects the temperature control water supply pipe <NUM> and the temperature control water discharge pipe <NUM>.

The ends of the temperature control flow path <NUM> are openings connected to the temperature control water supply pipe <NUM> and the temperature control water discharge pipe <NUM>. The control flow path <NUM> is formed so as to permit the exchange of heat with the base plate <NUM> when fixed to the manifold <NUM>.

That is, a part of the temperature control flow path <NUM> is provided as a groove in the surface of the manifold <NUM> to which the base plate <NUM> is fixed. In the present embodiment, the temperature control flow path <NUM> has a configuration in which a pair of temperature control water openings <NUM> are provided in the surface of the manifold <NUM> to which the base plate <NUM> is fixed. The primary (entrance) side and the secondary (exit) side of the temperature control water openings <NUM> communicate with each other via a groove in the surface opposite from the side of the manifold <NUM> to which the base plate <NUM> is fixed.

The temperature control water opening <NUM> can be provided in a region corresponding to the pressure chambers <NUM> and <NUM> of the base plate <NUM>, or a region corresponding to the second common liquid chamber <NUM> of the base plate <NUM>. Heat is generated by the driving of the first pressure chambers <NUM>, and the temperature of the first pressure chamber <NUM> and thus the temperature of the ink in the first pressure chamber <NUM> and on the secondary side (second common liquid chamber <NUM>) of the first pressure chamber <NUM> rise. Therefore, the temperature control of at least either the plurality of first pressure chambers <NUM> or the second common liquid chamber <NUM> is generally required.

In the present embodiment, a temperature control water opening <NUM> is provided in the region corresponding to each of the second common liquid chambers <NUM>. Particularly, the temperature control flow path <NUM> is provided with two different temperature control water openings <NUM> with branches into two at the side to which the temperature control water supply pipe <NUM> is connected from the side to which the base plate <NUM> is fixed.

That is, the manifold <NUM> of the present embodiment includes a pair of temperature control water openings <NUM> formed on the side to which the base plate <NUM> is fixed. The temperature control water openings <NUM> form a part of the temperature control flow path <NUM>. When manifold <NUM> and the base plate <NUM> are fixed to each other, the water flowing through each temperature control water opening <NUM> exchanges heat with a region corresponding to second common liquid chambers <NUM> of the base plate <NUM>. In this way, a temperature control flow path <NUM> that connects the temperature control water supply pipe <NUM> and the temperature control water discharge pipe <NUM> is formed.

The top plate <NUM> is provided on the surface of the manifold <NUM> opposite from the base plate <NUM>. The top plate <NUM> covers the manifold <NUM> to seal the ink supply flow path <NUM>, the ink discharge flow path <NUM>, and the temperature control flow path <NUM>. The top plate <NUM> includes openings <NUM> at positions facing the primary side and the secondary side of the ink supply flow path <NUM>, the ink discharge flow path <NUM>, and the temperature control flow path <NUM>. These openings <NUM> permit the flow paths <NUM>, <NUM>, and <NUM> to be fluidly connected to the pipes <NUM>, <NUM>, <NUM>, and <NUM>.

The ink supply pipe <NUM> is connected to the ink supply flow path <NUM> via a base block <NUM> and an opening <NUM> of the top plate <NUM>. The ink discharge pipe <NUM> is connected to the ink discharge flow path <NUM> via a base block <NUM> and an opening <NUM> of the top plate <NUM>. The temperature control water supply pipe <NUM> is connected to the primary side of the temperature control flow path <NUM> via a base block <NUM> and an opening <NUM> of the top plate <NUM>. The temperature control water discharge pipe <NUM> is connected to the second side of the temperature control flow path <NUM> via a base block <NUM> and an opening <NUM> of the top plate <NUM>.

In the present embodiment, the ink supply pipe <NUM>, the ink discharge pipe <NUM>, and one of the temperature control water supply pipe <NUM> or the temperature control water discharge pipe <NUM> are all disposed at one end of the manifold <NUM>. The other one of the temperature control water supply pipe <NUM> or the temperature control water discharge pipe <NUM> is disposed on the other end of the manifold <NUM>. In the present example, the temperature control water supply pipe <NUM> is grouped on the end of the manifold <NUM> with the ink supply pipe <NUM> and the ink discharge pipe <NUM>, and the temperature control water discharge pipe <NUM> is provided alone on the other end of the manifold <NUM>.

The ink supply pipe <NUM> and the ink discharge pipe <NUM> are disposed side by side with one another in the lateral (width) direction of the manifold <NUM>. The temperature control water supply pipe <NUM> is disposed adjacent to the ink supply pipe <NUM> and the ink discharge pipe <NUM>. In this example, the temperature control water supply pipe <NUM> is disposed closer to the center of the manifold <NUM> than the ink supply pipe <NUM> and the ink discharge pipe <NUM>.

In the present example, two separate base blocks <NUM> are provided. One base block <NUM> supports the ink supply pipe <NUM>, the ink discharge pipe <NUM>, and the temperature control water supply pipe <NUM>. The other base block <NUM> supports the temperature control water discharge pipe <NUM>. Each base block <NUM> is fixed to the top plate <NUM>. For example, the base block <NUM> includes a flow path therein, and fluidly connects a supported pipe to an opening <NUM> in the top plate <NUM>.

The circuit board <NUM> includes a wiring film <NUM> with one end connected to the wiring pattern of the actuator <NUM>. A driver IC <NUM> of the circuit board <NUM> is mounted on the wiring film <NUM>, and a printed wiring board <NUM> of the circuit board <NUM> is mounted on the other end of the wiring film <NUM> opposite from the end connected to the wiring pattern of the actuator.

The circuit board <NUM> drives the actuator <NUM> by applying a drive voltage to the wiring pattern of the actuators <NUM> by using the driver IC <NUM>. The driving of an actuator <NUM> in this manner increases or decreases the volume of the pressure chamber(s) <NUM>, which can operate to eject liquid droplets from a nozzle <NUM>.

A plurality of wiring films <NUM> can be provided, for example. In the present embodiment, two wiring films <NUM> are connected to each actuator <NUM>. The wiring film <NUM> is, for example, a Chip on Film (COF) on which the driver IC <NUM> is mounted. The driver IC <NUM> is electrically connected to the wiring pattern (electrodes) formed in the pressure chambers <NUM> via the wiring film <NUM>. The printed wiring board <NUM> can be a printing wiring assembly (PWA) on which various electronic components and connectors are mounted.

The liquid ejection head <NUM> can be incorporated in, for example, an ink jet recording device <NUM> such as illustrated in <FIG> or other type of the liquid ejection device. The liquid ejection head <NUM> is connected to the supply tank <NUM> provided in the ink jet recording device <NUM>. The liquid ejection head <NUM> can be a circulating type head that circulates ink to and from the supply tank <NUM> through the liquid ejection head <NUM> or a non-circulating type head that is supplied with ink from the supply tank <NUM> and then discharges ink into a maintenance device <NUM> during maintenance operations. The liquid ejection head <NUM> is disposed, for example, in a posture in which the nozzles <NUM> of the nozzle plate <NUM> faces downward towards a recording medium (e.g., a sheet or paper) or the like.

As depicted in <FIG>, the ink jet recording device <NUM> includes a housing <NUM>, a medium supply unit <NUM>,an image forming unit <NUM>, a medium discharge unit <NUM>, a conveyance device <NUM>, a temperature control device <NUM>, a maintenance device <NUM>, and a control unit <NUM>.

The ink jet recording device <NUM> in this example is an ink jet printer that performs an image forming process on paper P by ejecting a liquid, such as ink, while paper P is being conveyed along a predetermined conveyance path <NUM> from the medium supply unit <NUM> to the medium discharge unit <NUM> through the image forming unit <NUM>.

The medium supply unit <NUM> includes a plurality of paper feeding cassettes <NUM>. The image forming unit <NUM> includes a support unit <NUM> (that supports paper thereon during the printing process) and a plurality of head units <NUM> that are disposed adjacent to each other above the support unit <NUM>. The medium discharge unit <NUM> includes a paper discharge tray <NUM>.

The support unit <NUM> includes a conveyance belt <NUM> provided in a loop shape, a support plate <NUM> for supporting the conveyance belt <NUM> from the back side, and a plurality of belt rollers <NUM> provided on the back side of the conveyance belt <NUM>.

Each head unit <NUM> includes a liquid ejection head <NUM>, a supply tank <NUM> connected to the liquid ejection head <NUM>, a pump <NUM> for supplying ink, and a connection flow path <NUM> connecting the liquid ejection head <NUM> and the supply tank <NUM>.

In the present embodiment, liquid ejection heads <NUM> for four colors (cyan, magenta, yellow, and black) are provided, and thus four supply tanks <NUM> accommodating ink of each of these four colors are provided. Each supply tank <NUM> is connected to the liquid ejection head <NUM> by a connection flow path <NUM>.

The pump <NUM> is a liquid feed pump composed of, for example, a piezoelectric pump. The pump <NUM> is connected to the control unit <NUM> and can be driven and controlled by the control unit <NUM>.

Each connection flow path <NUM> includes a supply flow path connected to the ink supply pipe <NUM> of the liquid ejection head <NUM>. The connection flow path <NUM> also includes a collection flow path connected to the ink discharge pipe <NUM> of the liquid ejection head <NUM>. If the liquid ejection head <NUM> is a circulating type, the collection flow path will be connected to the supply tank <NUM>. If the liquid ejection head <NUM> is a non-circulating type, the collection flow path will be connected to the maintenance device <NUM>.

The conveyance device <NUM> conveys the paper P along the conveyance path <NUM> from the paper feeding cassette <NUM> to the paper discharge tray <NUM> through the image forming unit <NUM>. The conveyance device <NUM> includes guide plate pairs <NUM> to <NUM> (guide plate pairs <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) and conveyance rollers <NUM> to <NUM> (conveyance rollers <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) disposed at different points along the conveyance path <NUM>. The conveyance device <NUM> supports the paper P so that the paper can be moved relative to the liquid ejection head <NUM>.

The temperature control device <NUM> includes a temperature control water tank <NUM>, a temperature control flow circuit <NUM> (such as pipes and tubes) for supplying temperature control water, a pump that supplies the temperature control water, a temperature controller that adjusts the temperature of temperature control water, and the like. The temperature control device <NUM> supplies the temperature control water from the temperature control water tank <NUM> at a predetermined temperature controlled by the temperature controller to the temperature control water supply pipe <NUM> via the temperature control flow circuit <NUM> by action of the pump. The temperature control device <NUM> also collects the water discharged from the temperature control water discharge pipe <NUM> through the manifold <NUM> back into the temperature control water tank <NUM> via the temperature control flow circuit <NUM>. The temperature controller is, for example, a heater or a cooler.

The maintenance device <NUM> functions during maintenance to suction and collect ink remaining on the outer surface of the nozzle plate <NUM>, for example. If the liquid ejection head <NUM> is a non-circulating type, the maintenance device <NUM> collects ink in the head body <NUM> through a nozzle(s) <NUM> facing the second pressure chambers <NUM> during maintenance. The maintenance device <NUM> includes a tray, a tank, or the like for storing the collected ink.

The control unit <NUM> includes a CPU <NUM> (one example of a processor), a memory such as a read only memory (ROM) for storing various programs, a random access memory (RAM) for temporarily storing various data and image data, and an interface unit for data input from the outside and data output to the outside.

Next, the flow of ink and the flow of temperature control water for temperature control of the liquid ejection head <NUM> will be described. First, when the ink supplied to the ink supply pipe <NUM>, the ink flows through the two ink supply flow paths <NUM> of the manifold <NUM>. Then, the ink moves from the supply hole <NUM> of the base plate <NUM> facing the ink supply opening <NUM> of the ink supply flow path <NUM> to the first common liquid chamber <NUM>.

The ink that has moved to the first common liquid chamber <NUM> moves to the second common liquid chamber <NUM> by passage through the plurality of first pressure chambers <NUM> as illustrated by arrows in <FIG>. If a first pressure chamber <NUM> is driven, the ink in the first pressure chamber <NUM> will be ejected from the nozzle <NUM>. Any ink not ejected from the nozzle <NUM> moves to the corresponding second common liquid chamber <NUM>.

When the liquid ejection head <NUM> is a non-circulating type, the ink in the second common liquid chamber <NUM> moves to the third common liquid chamber <NUM> via second pressure chambers <NUM> and accumulates in the third common liquid chamber <NUM>. Then, if the secondary side of the ink discharge pipe <NUM> is opened during maintenance or the like, the ink in the second common liquid chamber <NUM> moves to the ink discharge pipe <NUM> through the discharge hole <NUM> of the base plate <NUM> and the ink discharge flow path <NUM> of the manifold <NUM>. Furthermore, by driving a second pressure chamber <NUM> during maintenance or the like, the ink in the second pressure chamber <NUM> will be ejected together with air accumulated in the second common liquid chamber <NUM> and the third common liquid chamber <NUM>, for example, this operates to bleed air from the liquid ejection head <NUM>.

When the liquid ejection head <NUM> is a circulating type, the third common liquid chamber <NUM> is not necessarily provided, and the discharge hole <NUM> can be provided in the second common liquid chamber <NUM>. The ink in the second common liquid chamber <NUM> moves to the ink discharge pipe <NUM> through the discharge hole <NUM> of the base plate <NUM> and the ink discharge flow path <NUM> of the manifold <NUM>.

If water (temperature control water) is supplied to the temperature control water supply pipe <NUM>, the water flows through the temperature control flow path <NUM> of the manifold <NUM> and moves to the temperature control water discharge pipe <NUM>. The water comes into contact with the base plate <NUM> at the temperature control water opening <NUM>, exchanges heat with the base plate <NUM>, and which can cool the base plate <NUM> or otherwise regulates temperature of the base plate <NUM>.

As a result, the ink in the plurality of pressure chambers <NUM> and <NUM> along with the pressure chambers <NUM> and <NUM> themselves can be cooled. Alternatively, ink of the second common liquid chamber <NUM> can be cooled. In some examples, the water (temperature control water) may be utilized to heat the ink instead of cooling the ink. That is, the temperature control water may be either cooled or heated to maintain the temperature of the ink at a level suitable for ejection from the nozzles. In some examples, the ink may be heated before the pressure chamber <NUM> is driven, and then cooled after the pressure chamber <NUM> is driven.

With the liquid ejection head <NUM> and the liquid ejection device <NUM> configured in this way, it is possible to control the temperature of the ink regardless of whether a circulating type or a non-circulating type liquid ejection head <NUM> is adopted.

In an above-described example, the head body <NUM> was described as a non-circulating type, but the head body <NUM> may be a circulating type instead. The head body <NUM> in some examples may have a configuration that does not include the third common liquid chamber <NUM>.

In an above-described example, the flow of ink in one system for supplying ink from one first common liquid chamber <NUM> to a pair of actuators <NUM> was described, but the present disclosure is not limited thereto. For example, the flow of ink in two systems may be adopted, with one first common liquid chamber <NUM> being provided for each actuator <NUM>. Such a liquid ejection head <NUM> may include, for example, two ink supply pipes <NUM> and two ink discharge pipes <NUM>, and two ink supply flow paths <NUM> and two ink discharge flow paths <NUM> in the manifold <NUM>.

The flow paths in manifold unit <NUM> can be varied in number and type as appropriate. That is, the shape and configuration of the ink supply flow path <NUM>, the ink discharge flow path <NUM>, the temperature control flow path <NUM>, and the positioning of pipes <NUM>, <NUM>, <NUM>, and <NUM> can be appropriately varied in the manifold unit <NUM> to correspond to the configuration of the head body <NUM> and the common liquid chambers <NUM>, <NUM>, and <NUM>.

Claim 1:
A liquid ejection head, comprising:
a base plate (<NUM>) with an actuator (<NUM>) on an upper surface side of the base plate;
a plurality of pressure chambers (<NUM>) formed in the actuator;
a first common chamber (<NUM>) connected to a first side of the plurality of pressure chambers;
a second common chamber (<NUM>) connected to a second side of the plurality of pressure chambers, the pressure chambers connecting the first common chamber to the second common chamber;
a nozzle plate (<NUM>) on an upper surface side of the actuator and having a plurality of nozzles at positions respectively corresponding to the pressure chambers;
a supply hole (<NUM>) in the base plate connected to the first common chamber;
a discharge hole (<NUM>) in the base plate connected to the second common chamber; and
a manifold (<NUM>) on a lower surface side of the base plate, the manifold having:
a liquid supply flow path (<NUM>) for supplying liquid to the supply hole from a liquid feed port on a lower surface side of the manifold, and
a liquid discharge flow path (<NUM>) for receiving liquid from the discharge hole, characterized in that:
the manifold (<NUM>) further comprises a temperature control flow path (<NUM>) for allowing a temperature control liquid to flow therethrough, and
the liquid ejection head further comprises:
a first temperature control pipe (<NUM>) connected to the temperature control flow path;
a second temperature control pipe (<NUM>) connected to the temperature control flow path, and
a maintenance pressure chamber (<NUM>) at a longitudinal end portion of the actuator, wherein
one end of the maintenance pressure chamber is connected to the second common chamber,
an opposite end of the maintenance pressure chamber is connected to the discharge hole, and
the nozzle plate includes at least one purge nozzle hole at a position corresponding to the maintenance pressure chamber.