Abstract: A cloth feeder for sewing machine comprises a reciprocatively movable needle arranged so as to sew the cloth on the bed, a pulse generator for generating the electric pulses in order to feed the cloth during the needle stays away from the cloth, a step motor actuated by the pulses from the pulse generator, and a rotator driven by the step motor and arranged in pressed contact with the cloth so as to feed it.

Abstract: A hydraulic damper is provided with a damping force adjusting mechanism. The damper includes a piston slidably positioned with a closed ended cylinder which functions to divide the interior of the cylinder into two chambers. Communication between the two chambers is provided by passageways partially defined by apertures and bores within the piston. Fluid flow between the two chambers via the passageways serves as the damping force. The damping force is made adjustable by a rotary valve positioned within one of the passageways which functions to vary the effective cross-sectional area of that passageway thus functioning as a damping force adjusting element. A device is provided to vary the damping force adjusting mechanism from the exterior of the hydraulic damper in accordance with a predetermined damping force.

Abstract: A cloth feeding apparatus having two feeding devices with respect to the feeding direction and adapted to feed a cloth under a tension by setting the feeding amount on the downstream greater than the feeding amount on the upstream.

Abstract: A cloth feed apparatus to be equipped with a sewing machine, the cloth feed apparatus including a roller driven by means of a stepping motor which is actuated in accordance with electric pulses generated by a detector detecting rotation of a main shaft of the sewing machine, the detector generating electric pulses by detecting slits of disc firmly mounted on a main shaft of the sewing machine.

Abstract: An electromagnetic locking type actuator is constituted by a control member reciprocatable in a fluid passage to control the fluid pressure in the passage, an electromagnetic device for applying a first magnetomotive force to the control member, and a magnetic device for always applying a second magnetomotive force to the control member. In the actuator, when an electric current in one direction is applied to the electromagnetic device the first and second magnetomotive forces are added to move the control member in an attracting direction so that the control member is attracted and held at its movement terminating position by the magnetic device even after the first magnetomotive force no longer acts at that position. When an electric current in a direction opposite to the one direction is applied to the electromagnetic device the first and second magnetomotive forces cancel each other thereby maintaining said control member in a magnetically released state.

Abstract: A vehicle height adjusting apparatus in which a sensor means detects the distance between the body and axles of a vehicle while the vehicle is parked or moving. A signal comparator divides the vehicle height detection range into a plurality of detection zones based on the sensor signals; a pulse converter circuit converts the signals into pulse signals of the detection zones; an integrator circuit integrates the pulse signals for a period of time; a determination circuit determines the vehicle height level and a fluid circuit controls the inflow and outflow of fluid into and out of a suspension device.