Abstract: A propeller for a marine propulsion system is disclosed which comprises a propeller hub having a casing formed from three segments (16a, 16b, 16c), each of which has a part of an opening (28) for mounting a propeller blade (34). A locking and unlocking mechanism (51, 54, 95, 100) is provided for disengaging the propeller blades to enable pitch adjustment of the blades. A push rod (50) is connected to the mechanism (100) to cause disengagement and adjustment of the pitch of the blades. The mechanism (100) includes a claw (101) having pivotally connected fingers (95). The hub also has a slide ring (51) having a load surface (61) is provided for receiving load when the propeller blades are unlocked to enable pitch adjustment to take place.

Abstract: A potentiometer is disclosed which comprises an opaque screen element (10) and light emitters and collectors (92) for transmitting light through the screen and detecting the light transmitted through the screen. The screen has three sections (A, V and B). The sections (A, V and B) have bars which are parallel to one another and extend transverse to the direction of movement of the screen (10). The section (A) has bars which are arranged in groups comprising the same number of bars, but each of a different thickness. The section (V) has two parts (35, 36), the first part has bars which are formed in the same manner as the section (A) except they are a mirror image to the bars in section (A) and each group comprises less bars than are in the groups in section (A). The second part of section (V) has individual bars which increase in thickness. Section (B) is a mirror image of section (A).

Abstract: A propeller for a marine propulsion system is disclosed which comprises a propeller hub having a casing formed from three segments (16a, 16b, 16c), each of which has a part of an opening (28) for mounting a propeller blade (34). A locking and unlocking mechanism (51, 54, 95, 100) is provided for disengaging the propeller blades to enable pitch adjustment of the blades. A push rod (50) is connected to the mechanism (100) to cause disengagement and adjustment of the pitch of the blades. The mechanism (100) includes a claw (101) having pivotally connected fingers (95). The hub also has a slide ring (51) having a load surface (61) is provided for receiving load when the propeller blades are unlocked to enable pitch adjustment to take place.