Abstract: A borescope device having an insertion tube, a camera head assembly, and a fluid supply system. The camera assembly includes through holes allowing fluid escape. The fluid supply system is controllable to force fluid through the through holes. The fluid supply system may be actuated to cool the camera head assembly.

Abstract: A manually rotated knob drive mechanism incorporates a torque override feature. If the knob turning force exceeds a predetermined torque limit the feature permits slippage between the knob and the associated stem or drive shaft. The knob can continue to rotate, under slippage, until the knob and stem are aligned at a predetermined mutual orientation, or home position. This occurs at only one home position. The torque override feature is formed of an insert molded into the knob, and having a bore in which there is an annular shoulder. A hub member fits into the insert and has an annular surface that faces the insert shoulder. The hub member attaches to the stem or shaft and a spring yieldably urges the hub member against the insert. There are protuberances on the insert shoulder and corresponding grooves or recesses on the hub member annular surface, which coincide with one another only at the home position. The knob drive can be employed on the steering control handle of a borescope, endoscope or guide tube.

Abstract: A fluid insensitive system for braking the displacement cables of an endoscopic insertion tube wherein at least one control wheel is mounted on the outside of the insertion tube control housing. A brake disc is slidably mounted adjacent the control wheel and is moved in and out of engagement with the wheel by an actuator. A ratchet mechanism acts between the control wheel and the brake disc to apply a restraining force against the wheel when the wheel and the brake disc are in engagement.

Abstract: An Endoscope having at least one control cable wherein a helically wound cylindrical spring is passed over one end of the cable and is crimped into deforming contact against the cable. Melted solder is flowed over and through the spring to wet the spring and the cable surfaces. The solder is allowed to solidify thus creating a strong joint between the cable and the spring.