Abstract: A water-tight structure for a multicore cable includes a sealed vessel in which electrical components are arranged, and a grommet having an insertion hole disposed at a multicore cable lead portion of the sealed vessel. The multicore cable is held in the insertion hole of the grommet and has a solder-dipped portion in the grommet which has been bent, a portion of the solder-dipped portion being covered with a metal sleeve.

Abstract: An electromagnetic pump includes a cylindrical member, a resin coil bobbin, a printed circuit board, a holder, and pump housing. Engaging projections are formed on a peripheral portion of a surface of the coil bobbin, which opposes the lid, and the electromagnetic pump components are held in the pump housing while they are biased in the axial direction of the cylindrical member by utilizing the engaging projections.

Abstract: In an electromagnetic pump, the inner end of an outlet pipe fixed in a pump housing extends for a predetermined length inside a sleeve housing a plunger to form a pump delivery pulsation absorption chamber around the outlet pipe. The inner end opening of this pipe is selectively closed by a control valve serving as a guide member for slidably guiding a valve body of a delivery valve along the axial direction. The fuel leakage prevention control valve and the pulsation absorption chamber are simply and optimally formed with a single construction.

Abstract: An electromagnetic pump includes a coil bobbin with an excitation coil, a pair of magnetic cylinders, a printed circuit board with a transistor, and a pump housing. The coil bobbin is disposed around a sleeve member having a plunger therein. The pair of magnetic cylinders are axially inserted from two ends of the bobbin between the inner surface of the coil bobbin and the outer surface of the sleeve member. The pump housing consists of a cup-like housing body and a lid. The plunger, the magnetic cylinders and the pump housing are made of a magnetic material to form a magnetic flux path from the excitation coil.

Abstract: An electromagnetic pump has a pump housing. The pump housing consists of a cup-like housing body with an outlet cylindrical portion at the center thereof and a lid member having an inlet cylindrical portion at the center thereof. The lid member is fixed to the cup-like housing body. The pump also includes a nonmagnetic sleeve member, a magnetic plunger slidably fitted in the nonmagnetic sleeve member, a return spring for biasing the plunger to a delivery side, inlet and outlet pipes, a coil bobbin arranged around the sleeve member, a transistor assembly consisting of a transistor and a heat sink, a printed circuit board, a holder mounted above the printed circuit board, a leaf spring arranged between the housing body and the holder. A plurality of studs extend on the outer side surface of the flange of the coil bobbin on which the transistor assembly is mounted and on an inner side surface of the holder.

Abstract: In an electromagnetic pump wherein a sleeve containing a reciprocating pump is clamped between inlet and outlet fixtures, a cylindrical rubber ring is mounted about the sleeve and compressed by the inlet and outlet fixtures to come into intimate contact against the sleeve thus forming a seal.