DE202004008952U1 - Capacitive proximity sensor for avionics, has large-surface grid structure of conductive materials woven into the laminate to reduce capacitance - Google Patents

Abstract

A proximity sensor uses fiber composite-structural components and functions according to the capacitive measurement principle and uses as the sensor surface a structurally active conductive surface of fiber composite materials. To reduce the capacitance, the active surface is insulated against the residual structure.

Description

In Many technical applications use a switching function required by the user. This is usually done via mechanical Switch or button. The disadvantage here is the wear that occurs and the low reliability due to the mechanical components used. Furthermore, mechanical Switches are limited in their dimensions and shapes.

alternative therefore proximity sensors are used the z. B. work according to the capacitive principle of action. Avoid this the use of mechanical elements, but require a conductive surface, which applied accordingly to the surface of the control element must become. For this, larger areas than operating surface come into use.

In Aviation is due to the demands for minimal weight and low integration effort an additional area, especially with large dimensions, problematic.

The In invention specified in protection claim 1, the problem is based a touch sensor to create the existing structural components as useful Uses the contact surface, offers a minimized weight and integration effort and also large controls allows.

This Problem is solved with the features listed in protection claim 1.

On capacitive sensor detects a touch on the change in the capacity of the concerned Sensor surface, by approaching z. B. a human hand is reached. A direct leader Contact is not necessary here, rather the charge shift is sufficient in the conductive elements. The circuit must be capacitive be closed, which by appropriate grounding of the sensor electronics is achieved.

With The invention achieves that structural components made of conductive Fiber bonded used as a contact surface become. For this purpose, the structural component is electrical with the sensor evaluation electronics connected and can thus be used as a sensor surface. electrical conductive surfaces in the sense of the invention represent z. B. layers of carbon fiber fabric. Alternatively, you can also grids made of metal threads, such as they z. B. used for lightning protection and introduced into the laminate will be used.

Around an aesthetic appealing solution too it makes sense to achieve this if there is direct contact with the manager area is not required and is accordingly free in design. This is possible due to the capacitive measuring principle, in which the contact is not must be electrically conductive.

These the structural component used is a large one Component, so the touch sensitivity can be increased by using only parts of the component as a sensor surface become. This can be more insulating by introducing them Layers z. B. can be achieved from glass, aramid or plastic films.

Becomes a directive for wanted the sensor, so that e.g. B. side and back touches do not lead to detection, so this can be done by appropriate shielding layers made of conductive material, which must be grounded can be achieved.

An advantageous embodiment of the layer structure is shown in 1 shown. This figure shows:

• - The actual sensor area ( 3 )
• - rear insulation to reduce capacity ( 4 )
• - the possibility of a spatially curved shape of the sensor surface ( 1 )
• - the possibility of an outer, decoratively designed layer ( 2 ) ,.

The rear CFRP fabric layers ( 5 ) be earthed to prevent sensitivity of the sensor to the rear. The sensor itself is then connected to the corresponding evaluation electronics via the connection ( 6 ) connected.

Claims (5)

Touch sensor using fiber composite structural components, characterized in that the touch sensor works according to the capacitive measuring principle and uses a structurally effective, conductive surface made of fiber composite materials as the sensor surface. touch sensor according to claim 1, characterized in that to reduce the Capacity the effective area is isolated against the residual structure. touch sensor according to claim 1, characterized in that to reduce the Capacity large grid made of conductive materials is integrated into the laminate. touch sensor according to claim 1, characterized in that the corresponding sensor surface any spatial bent accomplished becomes. touch sensor according to claim 1, characterized in that the sensor surface after insulating on the outside and is decorated decoratively.