A liquid discharge head includes a stacked body formed by plates stacked in a first direction, and having a liquid channel. The liquid channel includes: individual channels which include nozzles and pressure chambers communicating with the nozzles, respectively, and which are aligned in a second direction orthogonal to the first direction; a first common channel extending in the second direction and communicating with the individual channels; a second common channel extending in the second direction and communicating with the individual channels; first throttles each connecting one of the individual channels and the first common channel; and second throttles each connecting one of the individual channels and the second common channel. The plates include: a nozzle plate having the nozzles; a pressure chamber plate having the pressure chambers; a first common channel plate having the first common channel; and a second common channel plate having the second common channel.

A liquid ejection head includes a stack structure including plates stacked and bonded with an adhesive agent, individual channels formed in the stack structure, dummy channels formed in the stack structure separately from the individual channels, and a first relief groove formed in the stack structure separately from the individual channels and configured to trap therein an excessive adhesive agent. Each individual channel includes a pressure chamber to which pressure is applied for liquid ejection form a nozzle, a supply throttle channel connected to the pressure chamber, and a return throttle channel communicating with the pressure chamber. The supply throttle channel and the return throttle channel each have a smaller cross-sectional area than the pressure chamber. The dummy channels include dummy chambers arranged laterally to an array of the pressure chambers arranged in an array direction. The first relief groove is connected to the dummy channels.

An ejector for jetting droplets of viscous media onto a substrate is disclosed. The ejector comprises a jetting nozzle having a nozzle space and a nozzle outlet, and an impacting device for impacting a volume of the viscous medium in the nozzle space such that droplets of viscous medium is jetted from the nozzle space through the nozzle outlet towards the substrate. The ejector also comprise a sensor arrangement arranged after the jetting nozzle in the jetting direction, wherein the sensor arrangement is adapted to detect a jetted droplet of viscous medium passing thereby.

A liquid ejecting head includes: a flow channel forming substrate that forms an individual flow channel including a nozzle and a pressure chamber, a first common liquid chamber, and a second common liquid chamber; and a pressure generating element that causes a pressure change in a liquid in the pressure chamber, in which the first common liquid chamber is coupled to the second common liquid chamber via the individual flow channel, a compliance of the first common liquid chamber is larger than a compliance of the second common liquid chamber, and in the individual flow channel, a flow channel resistance between a first coupling portion with the first common liquid chamber and the pressure chamber is smaller than a flow channel resistance between a second coupling portion with the second common liquid chamber and the pressure chamber.

A liquid discharge head includes a stacked body formed by plates stacked in a first direction, and having a liquid channel. The liquid channel includes: individual channels which include nozzles and pressure chambers communicating with the nozzles, respectively, and which are aligned in a second direction orthogonal to the first direction; a first common channel extending in the second direction and communicating with the individual channels; a second common channel extending in the second direction and communicating with the individual channels; first throttles each connecting one of the individual channels and the first common channel; and second throttles each connecting one of the individual channels and the second common channel. The plates include: a nozzle plate having the nozzles; a pressure chamber plate having the pressure chambers; a first common channel plate having the first common channel; and a second common channel plate having the second common channel.

A liquid jetting apparatus includes: individual channels; and a manifold commonly provided for the individual channels. Each of the individual channels has: a nozzle; a pressure chamber arranged away from the nozzle in a predetermined direction to extend along a plane orthogonal to the predetermined direction and connected to the manifold, a connecting channel connected to the pressure chamber to form at least a part of a channel communicating the pressure chamber and the nozzle, and a circulation channel connected to the connecting channel to form a part of a channel communicating the connecting channel and the pressure chamber. The connecting channel has a throttle, and the throttle has a smaller diameter along the plane orthogonal to the predetermined direction than a diameter, of a part of the connecting channel except the throttle, along the plane orthogonal to the predetermined direction.

An inkjet recording apparatus to which a cartridge is attachable includes: a tank including a storage chamber and an outlet port; a recording portion including a damper chamber and a recording head; an ink passage; a pump configured to suck fluid in the damper chamber; a first switch; and a controller. After attachment of the cartridge, the controller is configured to perform an initial ink introduction process to supply the ink from the cartridge to the storage chamber. The initial ink introduction process includes: a first suction process to drive the pump for a first period of time in a state where the first switch is in a first state to allow ink in the storage chamber to be sucked toward the damper chamber; and after performing the first suction process, an open process to switch the first switch to a second state.

A liquid jetting apparatus includes: individual channels; and a manifold commonly provided for the individual channels. Each of the individual channels has: a nozzle; a pressure chamber arranged away from the nozzle in a predetermined direction to extend along a plane orthogonal to the predetermined direction and connected to the manifold, a connecting channel connected to the pressure chamber to form at least a part of a channel communicating the pressure chamber and the nozzle, and a circulation channel connected to the connecting channel to form a part of a channel communicating the connecting channel and the pressure chamber. The connecting channel has a throttle, and the throttle has a smaller diameter along the plane orthogonal to the predetermined direction than a diameter, of a part of the connecting channel except the throttle, along the plane orthogonal to the predetermined direction.

An ejector for jetting droplets of viscous media onto a substrate is disclosed. The ejector comprises a jetting nozzle having a nozzle space and a nozzle outlet, and an impacting device for impacting a volume of the viscous medium in the nozzle space such that droplets of viscous medium is jetted from the nozzle space through the nozzle outlet towards the substrate. The ejector also comprise a sensor arrangement arranged after the jetting nozzle in the jetting direction, wherein the sensor arrangement is adapted to detect a jetted droplet of viscous medium passing thereby.

An inkjet recording apparatus includes: a first tank; a second tank; a recording portion including a first damper chamber and a second damper chamber; a first switch; a pump; a second switch; and a controller. The first switch is configured to be switched between a first state and a second state. The second switch is configured to be switched between a third state and a fourth state. After attachment of first and second cartridges to the inkjet recording apparatus, the controller performs an initial ink introduction including one of: a first drive process to drive the pump in a state where the first switch is in the first state and the second switch is in the fourth state; and a second drive process to drive the pump in a state where the first switch is in the second state and the second switch is in the third state.