Abstract: A mechanical pencil includes a writing lead, a chuck unit for chucking the writing lead, and a cushion spring configured to elastically support the chuck unit in such a manner that the chuck unit is retractable with a writing pressure. An output of the cushion spring, in response to a cushion stroke, is non-linear, and a slope of a spring constant, in a region where the cushion stroke is relatively small, is smaller than a slope of a spring constant in a region where the cushion stroke is relatively large.

Abstract: A hand tool includes an outer barrel, an inner barrel housed in the outer barrel, and a rear barrel assembled to the outer barrel and the inner barrel. One of the outer barrel and the inner barrel includes a cam follower protruding in a radial direction of the hand tool, the other of the outer barrel and the inner barrel includes a cam groove engaging with the cam follower, and the cam follower is supported to be movable in a radial direction.

Abstract: A method for manufacturing a writing instrument includes inject molding a cushion spring of the writing instrument to form the cushion spring as one piece, and axially pushing out the cushion spring from a molding die set. The cushion spring elastically supports a tip of the writing instrument in an axial direction to a barrel of the writing instrument. The forming of the cushion spring includes forming a plurality of apertures in the cushion spring, one of the apertures being relatively arranged with another one of the apertures by rotations of angles at 90 degrees about the axial direction on an outer peripheral surface thereof, and forming a plurality of displacement regulating protrusions, one of the protrusions being relatively arranged with another one of the protrusions by rotations of angles at 90 degrees about the axial direction.

Abstract: A hand tool includes an outer barrel, an inner barrel housed in the outer barrel, and a rear barrel assembled to the outer barrel and the inner barrel. One of the outer barrel and the inner barrel includes a cam follower protruding in a radial direction of the hand tool, the other of the outer barrel and the inner barrel includes a cam groove engaging with the cam follower, and the cam follower is supported to be movable in a radial direction.

Abstract: A mechanical pencil includes a writing lead, a chuck unit for chucking the writing lead, and a cushion spring configured to elastically support the chuck unit in such a manner that the chuck unit is retractable with a writing pressure. An output of the cushion spring, in response to a cushion stroke, is non-linear, and a slope of a spring constant, in a region where the cushion stroke is relatively small, is smaller than a slope of a spring constant in a region where the cushion stroke is relatively large.

Abstract: A writing instrument includes a barrel, a tip, and a cushion spring that elastically supports the tip in the axial direction to the barrel. The cushion spring is formed as one piece by injection molding, the cushion spring includes an aperture on its outer peripheral surface, and a displacement regulating protrusion that protrudes and extends into the aperture along the axial direction. The protrusion prevents the cushion spring from compression beyond a prescribed length.

Abstract: A writing instrument according to an embodiment of the invention including, a chuck that chucks a writing lead, wherein the chuck includes a first chuck pawl which comes into point contact or line contact with the writing lead to press the writing lead so as to apply first contact stress to the writing lead; and a second chuck pawl which presses the writing lead so as to apply, to the writing lead, second contact stress that is lower than the first contact stress, and the first contact stress is configured such that, when a prescribed impact is applied to the writing lead, a contact portion of the writing lead subjected to the first contact stress fractures and absorbs the prescribed impact.

Abstract: A writing instrument according to an embodiment of the invention including, a chuck that chucks a writing lead, wherein the chuck includes a first chuck pawl which comes into point contact or line contact with the writing lead to press the writing lead so as to apply first contact stress to the writing lead; and a second chuck pawl which presses the writing lead so as to apply, to the writing lead, second contact stress that is lower than the first contact stress, and the first contact stress is configured such that, when a prescribed impact is applied to the writing lead, a contact portion of the writing lead subjected to the first contact stress fractures and absorbs the prescribed impact.

Abstract: A writing instrument according to an embodiment of the invention including, a chuck that chucks a writing lead, wherein the chuck includes a first chuck pawl which comes into point contact or line contact with the writing lead to press the writing lead so as to apply first contact stress to the writing lead; and a second chuck pawl which presses the writing lead so as to apply, to the writing lead, second contact stress that is lower than the first contact stress, and the first contact stress is configured such that, when a prescribed impact is applied to the writing lead, a contact portion of the writing lead subjected to the first contact stress fractures and absorbs the prescribed impact.

Abstract: Air direction changing members are disposed in an air inversion course so that the flows of air blown from a blow port of a front panel becomes substantially uniform throughout the whole of the blow port.