Micro-electromechanical nozzle arrangement with motion conversion coupling structures

1. A micro-electromechanical nozzle arrangement that comprises

a substrate;

a drive circuitry layer arranged on the substrate, the substrate and drive circuitry layer defining an ink inlet channel;

a static ink ejection structure positioned about the ink inlet channel;

an active roof structure arranged on the substrate and, together with the static ink ejection structure defining an ink chamber and an ink ejection port in fluid communication with the chamber, the active roof structure being displaceable with respect to the static ink ejection structure such that ink is ejected from the ink ejection port;

at least one pair of thermal actuators connected to the drive circuitry layer and oppositely oriented with respect to the roof structures;

at least one pair of coupling structures operatively linking respective thermal actuators and the roof structure, each coupling structure having a connecting member connected to the thermal actuator and a tongue and rod assembly located on the substrate, said assembly configured to convert an arcuate displacement of the connecting member under influence of the thermal actuator into linear displacement of the roof structure towards the substrate.

2. The coupling structure of claim 1 , wherein the tongue and rod assembly includes a pair of spaced proximal tongues positioned on the connecting member and extending towards the roof.

3. The coupling structure of claim 2 , wherein the tongue and rod assembly includes a pair of spaced distal tongues positioned on the roof structure and extending towards the connecting member so that the proximal and distal tongues overlap in a common plane parallel to the substrate.

4. The coupling structure of claim 3 , wherein the proximal tongues are interposed between the distal tongues.

5. The coupling structure of claim 4 , which includes two connecting plates, with each connecting plate connected to a set of one proximal tongue and one distal tongue by means of two rods from the plate to each tongue.

6. The coupling structure of claim 5 , wherein the rods and the connecting plates are dimensioned so that the rods and the connecting plates are able to distort to accommodate relative displacement of the roof structure and the connecting member when the roof is displaced towards the substrate.

7. The coupling structure of claim 1 , wherein the connecting member has a generally planar surface that is substantially coplanar with the roof structure when the nozzle arrangement is in a quiescent condition.