Abstract: A method for manufacturing a spark plug includes pressing a tip in a first direction from a first surface thereof toward a second surface thereof via a jig when the tip is in contact with an electrode base material; and welding the electrode base material to the tip being pressed by the jig. The jig has a recessed portion which is brought into contact with an edge of the tip, and the recessed portion has a diameter-decreasing portion having an inner dimension that gradually decreases toward a second direction opposite to the first direction. The inner dimension of a first end portion in the first direction of the diameter-decreasing portion is larger than the outer dimension of the edge, and the inner dimension of a second end portion in the second direction of the diameter-decreasing portion is equal to the outer dimension of the edge.

Abstract: A method for manufacturing a spark plug includes pressing a tip in a first direction from a first surface thereof toward a second surface thereof via a jig when the tip is in contact with an electrode base material; and welding the electrode base material to the tip being pressed by the jig. The jig has a recessed portion which is brought into contact with an edge of the tip, and the recessed portion has a diameter-decreasing portion having an inner dimension that gradually decreases toward a second direction opposite to the first direction. The inner dimension of a first end portion in the first direction of the diameter-decreasing portion is larger than the outer dimension of the edge, and the inner dimension of a second end portion in the second direction of the diameter-decreasing portion is equal to the outer dimension of the edge.

Abstract: A lever device in which a lid is mounted to an opening portion of a lever member without dropping down therefrom and with a good visual quality is disclosed. The lever device comprises a lever member swingably supported in a fixed system, an opening portion provided in the lever member to open in a radial direction, and a lid that is engaged to the opening portion to cover the opening portion therewith, wherein the lid is provided with a thin portion. Deflections are generated in such a manner as to concentrate on the thin portion of the lid.

Abstract: The objective is to reduce the size of a lever switch device. Disclosed is a lever switch device provided with a restriction wall (49) which is formed between first and second arms (19, 23) and which restricts the movement of the first and second arms (19, 23) against the rotation of first and second levers (13, 15) relative to a movable body (31); and engagement walls (45a, 45b, 47a, 47b) which are formed on first and second fitting portions (45, 47) and which are engaged with the first and second arms (19, 23) by the rotational transfer of the first and second arms (19, 23) caused by the shaft rotation of the first and second levers (13, 15), to cause first and second movable boards (41, 43) to perform a contact operation.

Abstract: A lever device in which a lid is mounted to an opening portion of a lever member without dropping down therefrom and with a good visual quality is disclosed. The lever device comprises a lever member swingably supported in a fixed system, an opening portion provided in the lever member to open in a radial direction, and a lid that is engaged to the opening portion to cover the opening portion therewith, wherein the lid is provided with a thin portion. Deflections are generated in such a manner as to concentrate on the thin portion of the lid.

Abstract: The objective is to reduce the size of a lever switch device. Disclosed is a lever switch device provided with a restriction wall (49) which is formed between first and second arms (19, 23) and which restricts the movement of the first and second arms (19, 23) against the rotation of first and second levers (13, 15) relative to a movable body (31); and engagement walls (45a, 45b, 47a, 47b) which are formed on first and second fitting portions (45, 47) and which are engaged with the first and second arms (19, 23) by the rotational transfer of the first and second arms (19, 23) caused by the shaft rotation of the first and second levers (13, 15), to cause first and second movable boards (41, 43) to perform a contact operation.

Abstract: Staking and soldering are eliminated to improve workability in assembly. A connection structure for a resistive element, in which the resistive element having lead wires at both ends is connected to a connection section of a base. A cover is fixably mounted on the base. Further, fixation claws capable of snap-holding the resistive element by elastic force and elastic tongues along lead wires are arranged on the cover. When the cover is fixed to the base, the elastic tongues are in elastic contact with the connection section through the lead wires to press the lead wires to the connection section.

Abstract: Staking and soldering are eliminated to improve workability in assembly. A connection structure for a resistive element, in which the resistive element having lead wires at both ends is connected to a connection section of a base. A cover is fixably mounted on the base. Further, fixation claws capable of snap-holding the resistive element by elastic force and elastic tongues along lead wires are arranged on the cover. When the cover is fixed to the base, the elastic tongues are in elastic contact with the connection section through the lead wires to press the lead wires to the connection section.