公开(公告)号：US20190337294A1

公开(公告)日：2019-11-07

申请号：US16470940

申请日：2017-04-19

Applicant: HEWLETT-PACKARD DEVELOPMENT COMPANY, L.P.

Inventor： David BUTINYA ,  Marta COMA VIVES ,  Albert CRESPI SERRANO ,  Joan-Albert MIRAVET JIMENEZ

IPC: B41J2/175 ,  G01L19/00 ,  G01L9/00 ,  G01L7/08

Abstract: A differential pressure sensor is used for measuring or identifying a pressure difference, for example to determine a movement or speed of fluid in a fluid conduit or printer re-circulation conduit. The differential pressure sensor determines the difference between an air pressure and a fluid pressure, wherein the fluid is moving in a flow channel. The flow channel includes a surface conveying a fluid between a first port and second port. An opening in the surface of the flow channel provides a fluid communication between the differential pressure sensor and fluid. Moreover, the sensor is arranged in air communication with the pressure box, such as to allow the differential pressure sensor to identify the pressure difference between the air pressure in the pressure box and the fluid pressure in the flow channel.

公开(公告)号：US20230286285A1

公开(公告)日：2023-09-14

申请号：US18006084

申请日：2020-07-20

Applicant: Hewlett-Packard Development Company, L.P.

Inventor： Dorkaitz Alain VAZQUEZ FERNANDEZ ,  Alvin Zheng-Hui YU ,  Joan-Albert MIRAVET JIMENEZ ,  Albert CRESPI SERRANO

IPC: B41J2/175 ,  B41J2/17

CPC classification number: B41J2/17596 ,  B41J2/1707

Abstract: A printing fluid delivery system comprising a fluid pump having an inlet and an outlet, a valve connected to the outlet of the fluid pump, and a controller to close the valve while the fluid pump is driven to increase the pressure at the outlet of the fluid pump based on a service condition and to open the valve based on a predefined relief condition to relieve the pressure at the outlet of the fluid pump.