Systems and methods are provided for cover plates for printheads. One embodiment is an apparatus that includes a cover plate for a printhead. The cover plate includes multiple layers of electrically conductive material, a layer of nonconductive ferrite that is sandwiched between the multiple layers, and at least one connector that penetrates through the multiple layers and the layer of nonconductive ferrite to form a conductive pathway for electric current between the multiple layers through the layer of nonconductive ferrite. The cover plate also includes at least one opening that penetrates through the multiple layers and the layer of nonconductive ferrite, and that is configured to align with nozzles of the printhead.

An ink jet recording head that includes a substrate having an ejection orifice for ejecting a liquid and a member provided with a recessed portion for accommodating the substrate, the head including a gap formed between a wall of the recessed portion of the member and the substrate, and a sealing material that seals the gap, in which the sealing material contains a cured product of a composition containing at least a hydrogenated bisphenol A type epoxy resin, a solid basic compound, and polythiol.

A liquid discharge head includes a plurality of nozzle arrays arranged in a first direction. The plurality of nozzle arrays each includes nozzles from which a liquid is discharged, the nozzles arranged in a second direction intersecting the first direction, and one of two nozzle arrays of the plurality of nozzle arrays adjacent to each other in the first direction include at least two nozzles arranged at different nozzle intervals from corresponding nozzles of another of the two nozzle arrays in the first direction.

A liquid discharge apparatus includes: a liquid discharge head configured to discharge a liquid from a nozzle, the liquid discharge head including: a liquid chamber communicating with the nozzle; a pressure generator configured to deform the liquid chamber to apply pressure to the liquid in the liquid chamber; and circuitry configured to apply a drive signal to the pressure generator to drive the pressure generator, the drive signal including at least one drive pulse. The drive pulse includes: an expansion element to expand the liquid chamber to a first volume; a holding element to hold the first volume of the liquid chamber expanded by the expansion element for a predetermined time; and a contraction element to contract the liquid chamber from the first volume held by the holding element to a second volume.

A head unit includes a recording head and a unit frame. The unit frame includes a main frame extending along a width direction orthogonal to a conveyance direction of a recording medium, and is configured to hold one or more recording heads on both side surfaces of the main frame. The main frame includes: a main body portion having a flat-plate shape and standing along the width direction; and bent portions formed by perpendicularly bending both end portions of the main body portion in the width direction. The unit frame includes a pair of reinforcing members provided at the bent portions. The reinforcing members each include a side wall portion opposed to the main body portion and a bottom surface portion provided so as to extend in a horizontal direction from a lower end portion of the side wall portion.

A head unit includes a recording head, a head-side frame, a unit frame, a first head mounting member, a second head mounting member, a head angle adjustment mechanism, and an urging member. The unit frame is configured to hold the recording head on both side surfaces of a main frame standing along a width direction orthogonal to a conveyance direction of a recording medium. The urging member is arranged on a side opposite to an opposing surface of the first head mounting member and the second head mounting member with respect to the main frame, and is configured to urge the head-side frame in a direction of separating away from the main frame, A counteraction of a pressing force that acts on the head-side frame from the urging member acts on the first head mounting member and the second head mounting member from the head-side frame.

A liquid discharge head includes: a nozzle plate having: a nozzle from which a liquid is to be discharged in a liquid discharge direction; and a nozzle face having the nozzle, the nozzle face directed in the liquid discharge direction; a nozzle protector configured to cover a portion of the nozzle face other than the nozzle; and a channel substrate including: a bonding part bonded to the nozzle protector with an adhesive; and a recess in a transverse portion of the bonding part extending in a transverse direction of the liquid discharge head, the recess filled with the adhesive.

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.

A liquid discharge device in which a drive circuit substrate that outputs a first drive signal supplied to a first electrode, a substrate, a first drive circuit that has a first circuit element in which a ground potential is supplied to one end and outputs the first drive signal, a first capacitor in which one end is electrically coupled to the second electrode and a ground potential is supplied to the other end, and a second capacitor in which one end is electrically coupled to the second electrode and a ground potential is supplied to the other end, the substrate includes a first surface and a second surface, the first capacitor is a chip capacitor, the second capacitor is an electrolytic capacitor, the first circuit element and the first capacitor are provided on the first surface, and the second capacitor is provided on the second surface.

A liquid discharge device including a drive circuit substrate that drives a piezoelectric element of a liquid discharge head, and that includes a substrate which includes a first wiring layer having a first wiring through which the first drive signal propagates, a second wiring layer having a second wiring through which the second drive signal propagates, and a third wiring layer located between the first wiring layer and the second wiring layer and having a fourth wiring through which the reference voltage signal propagates, in which a third wiring through which the third drive signal propagates is provided on any one of the first wiring layer, the second wiring layer, and the third wiring layer.