Abstract: A knock detecting apparatus for internal combustion engines is provided with a vibrating rod of a magnetic material having a resonance characteristic in a knock frequency hand of an engine, a free end of the vibrating rod is inserted in a round through hole of a core to form an air gap between the inner surface of the round through hole and the outer surface of the vibrating rod, and the air gas constitutes a portion of a magnetic path between the core and the free end of the vibrating rod. The vibrating rod is allowed to vibrate in more than one directions and air gaps are also formed in respective vibrating directions thereby enabling to detect vibrations due to knock in more than one directions.

Abstract: A vibrator having a resonant frequency within a knocking frequency range forms a part of a magnetic path. The vibrator vibrates in response to the vibration of an internal combustion engine and this changes the reluctance of the magnetic path. The change in the reluctance is sensed by a coil to detect the presence of knock. The vibrator is enclosed with a damper substance consisting of a liquid or sol substance having viscosity of flow properties so that the vibration of the vibrator is restricted and the Q of the resonance characteristic of the vibrator is deteriorated, thus increasing the substantial range of frequency detection of the apparatus. If necessary, the damper substance is heated to maintain its viscosity at a predetermined value.

Abstract: In a feedback type ignition timing control system for internal combustion engines, the predetermined correction advance/retard angle values are stored in a read/write memory at the respective storage areas defined by the respective operating conditions of an engine, and the correction advance/retard angle values are each separately rewritten in accordance with the detected associated engine condition in response to a signal detecting the feedback factor. The advance/retard angle value for the ignition timing corresponding to the detected engine condition is separately determined in accordance with the corresponding rewritten advance/retard angle value and the ignition timing is controlled to suit the respective engine conditions in accordance with the correction advance/retard angle values preliminarily rewritten in response to the feedback factor.

Abstract: A knock detector device for internal combustion engines comprises a first sensor for sensing the vibrations of an engine within its knocking frequency range, a second sensor for sensing the vibrations of the engine irrespective of the engine knocking frequencies, and a noise suppressing circuit for eliminating the noise in the output signal of the first sensor by means of the output signal of the second sensor.

Abstract: A knock detecting apparatus for internal combustion engines, includes at least two vibration detectors having different resonance characteristics and encased in one container. The vibration detectors are comprised by piezoelectric devices (bimorph cells) or magnetic devices having reed members of magnetic material. The vibration detectors are interconnected by a lead wire to combine the outputs thereof and to produce a cumulative output.

Abstract: A torque detecting system for the internal combustion engines is disclosed. Pressure detecting device is arranged between the engine body and the engine support for detecting the pressure generated between the engine body and the engine support. An electrical circuit generates a torque detection signal in response to a detection signal produced from the pressure detecting device.

Abstract: A knock detecting apparatus for an internal combustion engine includes a vibrating reed of magnetic material. One end of the vibrating reed is fastened to a supporting member interposing therebetween a magnet and one end of a core. The free end of the vibrating reed confronts with the other end of the core with an air gap therebetween to form a magnetic path including the magnet, vibrating reed, air gap and core. As the vibrating reed vibrates in response to vibration of the engine on which the supporting member is securely mounted, the distance of the air gap changes causing a change in magnetic flux passing through the magnetic path. The change of magnetic flux is detected by a coil wound on the core. The resonance characteristic of the vibrating reed is arranged to fall in the frequency range of the knocking.