Hewlett-packard Development Company, L.p.

Jordi Hernandez Creus

Yngvar Rossow Sethne

Marc Bautista Palacios

Josep M Aymerich I Bolta

Juan Luis López Rodríguez

Ricard Silvestre Rivero

Marta Coma Vives

Mauricio Seras Franzoso

Jose M Rio Doval

Francisco Guerrero Carvajal

Ignacio Picatoste Olloqui

Jesus Garcia Maza

Jesús García Maza

Lorena Fernández Llorens

Ricard Silvestre

Oriol Sola Tapias

Javier Chavarria Roe

Xavier Ponce Garcia

A printing apparatus is disclosed. The printing apparatus comprises a rotating housing comprising a wall with an inner side defining a chamber and an outer side. The wall has a bore communicating the inner side and the outer side, and the chamber is to receive a fluid container. The printing apparatus also comprises a fix frame holding the rotating housing. The printing apparatus further comprises an optical sensor comprising an emitter to issue a detecting optical signal through the bore and a receiver to receive a detected optical signal associated to the detecting optical signal. The detected signal is sent to a controller to determine whether the fluid container is present in the rotating housing.

Rotating housing with sensor

There is disclosed a method of supplying an n-channel transistor, operating as a voltage regulator, with a supply voltage and providing a control voltage to the n-channel transistor. The n-channel transistor is controlled by the control voltage to output an operating voltage of a printhead at a predetermined voltage.

Printhead voltage regulators

A system comprises a printhead including a nozzle, a temperature sensor and a processor. The temperature sensor detects the temperature of a location of a print surface upon firing the nozzle to eject a drop of printing fluid to the location of the print surface. The processor determines whether the nozzle ejected the drop properly using the detected temperature.

Thermal based drop detection

Devices and methods for calibrating communication lines are disclosed. A clock sets a frequency of transmission through a communication line. A delay compensator, comprising multi-tap delay lines introduces delays in a transmitted message to compensate for skew in the communication line. An error comparator, coupled to the delay compensator, identifies errors in the messages transmitted through the multi-tap delay lines above an error margin. A delay selector, coupled to the error comparator and to the delay compensator, selects taps of the multi-tap delay lines of the delay compensator. Taps of the multi-tap delay lines where no errors are identified for the selected clock frequency are stored in a memory.

Calibrating communication lines

A diagnostic device comprises a comparison section to compare an input voltage with a threshold voltage, wherein the input voltage is a power supply voltage for a component on a circuit board; and an indicator to provide an indication of the result of the comparison by the comparison section, the indication to render the circuit board identifiable to direct inspection, wherein the supply of power to the component is independent of the result of the comparison.

Diagnostic device, apparatus and method

A printer is disclosed. The printer uses a target located on one side of media to position an image on the other side of the media. The printer backlights the media and uses a sensor that locates the target through the backlit media.

Locating a target through media

According to one example, there is provided a system for compensating for changes in printhead-to-printhead spacing in a printing system having multiple printheads mountable on a printhead support. The system includes a measurement system to determine a change in printhead-to-printhead spacing between different ones of mounted printheads, and a processor to determine compensation to be applied to the printing system to compensate for the determined change in printhead-to-printhead spacing.

Compensating for changes in printhead-to-printhead spacing

A power supply circuit has parallel supply and control branches each with fuses, the power supply branch comprising at least one replaceable fuse. The supply branch is connected to one or more electrical components of an electrical device, such as the actuator and sensors of a printer, and the supply branch is connected to control or monitoring components. A circuit comprising lights indicates correct or faulty operation of the various parts of the supply circuit.

Growing community of inventors

Barcelona, Spain

Jordi Hernandez Creus