Reduced mechanical coupling with structured flex circuits
View Patent ↗An actuator assembly including a flexible printed circuit and a method for making such an actuator assembly are provided. The flexible printed circuit includes a body having a top side and a bottom side, with the body defining a plurality of bumps extending from the bottom side. A first bump of the plurality of bumps is disposed adjacent to a second bump of the plurality of bumps, and the body further defines at least one relief configured to reduce movement of the second bump caused by movement of the first bump. The flexible printed circuit also includes a plurality of contact pads disposed on the bottom side of the body at least partially at the plurality of bumps, with the plurality of contacts pads being configured to be electrically coupled to a power source and to a piezoelectric transducer.
1. An actuator assembly for an inkjet printer, comprising:
an array of piezoelectric actuators;
a diaphragm coupled with the array of piezoelectric actuators, wherein the diaphragm is configured to displace a volume of ink when one or more of the array of piezoelectric elements is excited;
a standoff layer disposed adjacent to the array of piezoelectric actuators, such that the array of piezoelectric actuators is disposed between the standoff layer and the diaphragm, the standoff layer defining apertures therethrough aligned with at least some of the array of piezoelectric transducers; and
a flexible printed circuit disposed adjacent to the standoff layer, the flexible printed circuit comprising:
a body having a top side and a bottom side, the body defining a plurality of bumps extending from the bottom side, the plurality of bumps being aligned with and extending at least partially through the apertures of the standoff layer;
a first embossed contact pad disposed on the bottom side of the body and at least partially at one or more of the plurality of bumps, the first embossed contact pad physically contacting at least one of the array of piezoelectric transducers; and
a second embossed contact pad disposed on the bottom side of the body and at least partially at one or more of the plurality of bumps, the second embossed contact pad physically contacting at least one of the array of piezoelectric elements,
wherein the body comprises at least one cutout relief configured to reduce movement of the second embossed contact pad caused by movement of the first embossed contact pad.
2. The assembly of claim 1 , wherein the at least one cutout relief extends partially through the body, such that the cutout relief defines an area of reduced thickness in the body.
3. The assembly of claim 1 , wherein the at least one cutout relief is defined between the first and second embossed contact pads.
4. The assembly of claim 1 , wherein the at least one cutout relief defines a lattice pattern in the body overlaying the first embossed contact pad, the second embossed contact pad, or both.
5. The assembly of claim 1 , wherein the body has a thickness of zero at the at least one cutout relief, such that the at least one cutout relief defines one or more openings through the body.