Abstract: A vacuum booster is configured so that at least when an input rod is released, a front surface of a flexible portion of a valve element communicates with a first port which communicates with a vacuum chamber. A valve element holder is formed of a single member made of a sheet of steel which includes a rim portion, an annular arm portion, and a crimp holding portion. The rim portion is fitted to an inner circumferential surface of a valve cylinder via a seal member. The annular arm portion extends inwards in a radial direction from a front end of the rim portion. The crimp holding portion extends from an inner circumferential end of the arm portion to form a bag-like shape and to narrow a front opening portion thereof. The crimp holding portion crimp holds a mounting bead portion of the valve element from rear thereof.

Abstract: An electrical connection structure of an electronic board includes: a board support member formed of synthetic resin; an electronic board fixed to the board support member; an electrical connection pad disposed on the electronic board; a bus bar disposed in the board support member; and a bonding wire that electrically connects the electrical connection pad and the bus bar. The bus bar includes: an exposed portion exposed in a face of the board support member; an embedded portion embedded in the board support member; and a connection portion extending from the exposed portion and being electrically connected to an electrical component. An end of the bonding wire is bonded to the exposed portion, and a first cut portion is formed in the embedded portion.

Abstract: The seal member includes a tetrafluoroethylene-propylene copolymer (FEPM) and carbon nanofibers. The seal member has a number of cycles to fracture of 10 or more when subjected to a tension fatigue test at a temperature of 150° C., a maximum tensile stress of 2 N/mm, and a frequency of 1 Hz. The seal member exhibits excellent heat resistance and abrasion resistance.

Abstract: A method of producing a carbon black composite material includes: a step (a) of mixing an elastomer and carbon black to obtain a composite elastomer; and a step (b) of mixing the composite elastomer and a matrix material to obtain a carbon black composite material in which the carbon black is uniformly dispersed in the matrix material.

Abstract: A normally closed solenoid valve includes a fixed core, a valve portion including a valve seat and a valve body, a movable core disposed between the fixed core and the valve seat, a resilient biasing member for biasing the movable core in a valve-closing direction and a coil. When energized, the coil generates an attracting force between the movable core and the fixed core against a biasing force by the resilient biasing member to cause the movable core to retreat from an initial position where the valve seat is in a closed state. When a characteristic graph line of spacing distance/attracting force that defines the attracting force in relation with a spacing distance between the fixed core and the movable core provides an inclination A (N/mm) at the initial position, the compression resiliency coefficient of the resilient biasing member is set to A (N/mm).

Abstract: A control lever assembly for a lawn mower has a main lever and an auxiliary lever pivotably mounted on lawn mower handle. The main lever is operatively connected through spring biased wire to tend to open a clutch and apply a brake for a rotary cutter of the lawn mower. The auxiliary lever when manually held against the mower handle pushes a resilient arm on the main lever out of engagement with a first stop on the body, thereby automatically causing the main lever to connect the clutch and disengage the brake. A spring biased second movable stop on the auxiliary lever is received in a recess in the main lever to detent the main lever in the locked position for operation of the mower. When the auxiliary lever is released manually by the operator, the second movable stop carried thereby is retracted out of the recess on the main lever to automatically return the wire to disconnect the clutch and engage the brake.