Spring Contact Gap Sensors

Spring Contact Gap Sensors

Spring Contact Gap Sensors

Capacitec Spring Contact Gap Sensors were developed in response to customers that required a more accurate and repeatable electronic method to measure gaps where one or both of the target surfaces are uneven or non-conductive. A contact wand is also used when one or both sides of the target gap are dimensionally smaller than the sensor. For example when measuring a commercial aircraft door edge gap, one target side typically measures only 0.0394” (1.0 mm). Another example where contact wands are used is in determining the air gap between the edge of a power turbine blade and the inside diameter of the casing. In this example the target side that has an odd shape is the radiused end of the turbine blade.

The Spring Contact Sensor is matched to a Gapman or Gapmaster3 which is well suited for the production environment due to its portability and ease of access to targets.

Here’s how a portable spring contact wand blade length measurement system would be used to measure gaps between the edges of Power Turbine blades and the inside diameter of the casing.

• A double-sided GPD-5 non-contact displacement sensor is installed onto a metal wand with two flexible leaf springs placed on top and bottom to provide the grounded target.
• When the wand is introduced into the gap between the blade tip and the outside diameter of the Power Turbine casing, the leaf springs bend inward toward the sensors giving a precise reading of the air gap.
• The gap measurement is viewed on the Gapman or Gapmaster3 electronics package display and can be saved and sent to a host computer via RS232 or USB.

Standard Spring Contact Wands

Size Key: Inch (mm)

STYLES	LENGTH	WIDTH	UNCOMPRESSED THICKNESS	COMPRESSED THICKNESS	SPEC SHEETS
GPD-2(.022)-A-150	5.906 (150)	0.394 (10.00)	0.300 (7.62)	0.022 (0.56)	5509-6947
GPD-4(.03)-A-350	13.780 (350)	0.394 (10.00)	0.300 (7.62)	0.030 (0.77)	5509-6999
GPD-5(.022)-A-150	5.906 (150)	0.551 (14.00)	0.300 (7.62)	0.022 (0.56)	5509-7068
GPD-10(.034)-A-150	5.906 (150)	1.063 (27.00)	.534 (13.56)	0.034 (0.86)	5509-8667
GPD-10(.034)-A-350	13.780 (350)	1.063 (27.00)	.534 (13.56)	0.034 (0.86)	5509-7574
GPD-5(.030)-A-500	19.685 (500)	.472 (12.00)	.300 (7.62)	0.030 (0.77)	5509-8716
GPD-5(.030)-A-800	31.496 (800)	0.472 (12.00)	0.300 (7.62)	0.022 (0.56)	5509-8541