A liquid discharging head is provided with: individual channels; a first common channel; and a second common channel. The individual channels include: first individual channels which have first pressure chambers and which are aligned in a second direction to form a first individual channel array, and second individual channels which have second pressure chambers and which are aligned in the second direction to form a second individual channel array; the first individual channel array and the second individual channel array are arranged in a third direction. The first common channel communicates with both of the first individual channels and the second individual channels; and the first pressure chambers and the second pressure chambers do not overlap with the second common channel in a first direction, and do not overlap with each other in the second direction.

A liquid discharge device including a first drive circuit, a second drive circuit, a third drive circuit, a fourth drive circuit, a connector coupled to a discharge head, and a substrate that includes a first wiring which couples the connector and the first drive circuit outputting a first drive signal, a second wiring which couples the connector and the second drive circuit outputting a second drive signal, a third wiring which couples the connector and the third drive circuit outputting a third drive signal, and a fourth wiring which couples the connector and the fourth drive circuit outputting a fourth drive signal, in which the first wiring is shorter than the second wiring, the third wiring, and the fourth wiring, and the fourth wiring is longer than the first wiring, the second wiring, and the third wiring.

The head system includes: a plurality of heads disposed staggered along a first direction; a sub-tank disposed above the heads and configured to distribute a liquid to each of the heads; a plurality of liquid channels; a chiller configured to cool the heads, including a manifold disposed between the heads and the sub-tank in an up-down direction; and a casing having a pair of inner surfaces opposed to each other in a second direction orthogonal to the first direction and the up-down direction. Each of the liquid channels extends linearly parallel to the up-down direction in an entire region between the sub-tank and one of the heads. Each of the plurality of liquid channels and the manifold are aligned in the second direction between the pair of inner surfaces of the casing.

An inkjet recording apparatus includes a conveying portion, a recording portion including a line head including a plurality of recording heads, a temperature detecting portion, a cooling mechanism, and a control portion. The cooling mechanism includes a storing portion that stores cooling liquid, a circulation path of the cooling liquid that is arranged to be branched into a plurality of branch paths passing near the recording heads, a heat dissipating portion that dissipates heat of the cooling liquid, and a pump that causes the cooling liquid to circulate. If there exists, among the recording heads, a recording head that is predicted to undergo a temperature rise, the control portion increases a flow amount or circulation time of the cooling liquid in whichever of the branch paths serves as a flow path of the cooling liquid flowing toward the recording head that is predicted to undergo a temperature rise.

An intermediate transfer body includes a surface layer, an elastic layer, and a heat-insulating layer contiguously in the mentioned order, and the surface layer, the elastic layer, and the heat-insulating layer satisfy the following Equations 1 to 4:

(C1+C2)×Δt≦Q  Equation 1:

100 MPa≦E1≦1,000 MPa  Equation 2:

0.5 MPa≦E2≦50 MPa  Equation 3:

λ3≦0.13 W/m.Math.K≦λ1≦λ2.  Equation 4:

A liquid ejection head includes a nozzle for ejecting a droplet of a liquid, a pressure chamber connected to the nozzle, an actuator for changing a volume of the chamber according to a voltage signal, and a drive circuit generating the signal for ejecting n droplets, where n is an integer of 3 or more. The signal includes (n−1) ejection pulses, comprising a first pulse lowering the voltage signal to a first value to expand the chamber and then to a second value to contract the chamber, and a second pulse lowering the voltage signal to the first value and then to a third value higher than the second value. The pulses are input at intervals of 0.8λ to 1.2λ, where λ is a primary natural vibration period of the chamber filled with the liquid.

A liquid ejection head includes: head units arranged in a first direction; first individual heat dissipators each corresponding to one of the head units and disposed on a first side of the head unit in a second direction; and a first common heat dissipator disposed on the first side of the head units in the second direction. The first common heat dissipator extends in the first direction and shared among the head units. Each head unit includes: a unit body including an actuator; and a first driver integrated circuit disposed on the first side of the unit body in the second direction. Each of the first individual heat dissipators is disposed between the first driver integrated circuit and the first common heat dissipator of the head unit so as to be in thermal contact with the first driver integrated circuit and the first common heat dissipator.

An embodiment of the present invention provides an ink jet printing apparatus including: a print head including a printing element array provided with printing elements each configured to generate thermal energy required to eject an ink, a supply flow channel provided along the printing element array and configured to supply the ink to the respective printing elements, an opening provided to the supply flow channel and configured to cause the ink to flow in, and heating units provided along the supply flow channel and configured to heat the ink inside the supply flow channel; and a heating control unit configured to carry out heating control of the heating units based on a heating pattern determined based on heating intensity distribution, the heating intensity distribution representing heating intensities corresponding to the respective heating units and representing the heating intensities corresponding to positions in a direction of the printing element array.

A method for manufacturing a printing bar unit for a printing system includes the steps of providing a support bar having a plurality of primary mounting positions, providing a plurality of exchangeable printheads having a plurality of inkjet nozzles, and releasably mounting the printheads to the support bar. Preceding the step of releasably mounting the printheads to the support bar, a plurality of reference organs are connected at the primary mounting positions to the support bar and undergo an alignment finishing process for forming a plurality of accurate secondary mounting positions, and then in a subsequent step the printheads are releasably mounted to the secondary mounting positions on the reference organs. A dimensional tolerance of the secondary mounting positions on the reference organs relative to each other is more accurate than a dimensional tolerance of the primary mounting positions on the support bar relative to each other.

There is provided head system including: head and channel member. The head includes four manifolds each having: common channel extending in first direction and inlet connected to the common channel. The four manifolds include first to fourth manifolds. The channel member includes: first member having supply port, and second member. The channel member is formed with first to fourth supply channels extending between the supply port and the inlet of the first to fourth manifolds, respectively. In two of the four manifolds, the inlet is connected to end on first side of the common channel, and in remaining two of the four manifolds, the inlet is connected to end on second side of the common channel. Each of the third and fourth supply channels is formed in both the first and second members.