Vehicle change-speed gear position recognising appts. - has hole mask which interrupts magnetic flux from permanent magnets to reed switches fitted directly to gears and activates position indicating circuit

摘要

The appts. uses a magnetic field to recognise the position of the gears. The gear changing shaft (3) is mounted so that it can be shifted axially as well as rotated about its axis and at least one magnetic field is altered by the movement of this shaft. In this way different reed switches fitted directly to the gears are activated, thus opening and closing a circuit which provides signals indicating the position of the gears. The reed switches (10) fitted as a matrix on a plate (9) and some permanent magnets (7) fitted in relation to the reed switches on a second plate (6) are rigidly connected with a wall (2) of the housing of the gears. Between the plates there is mounted a hole mask (5) so that it can move in response to the gear changing shaft connected to it. The mask interrupts the magnetic flux from the permanent magnets to the reed switches or allows it through according to the openings (11). ADVANTAGE - Improvement in accuracy of indication without using any mechanical contact with gears.