A mechanical pencil includes a barrel extending in a longitudinal direction, a lead-propelling mechanism, a lead reservoir, a side button, and an eraser-propelling mechanism having a helical cam. The lead-propelling mechanism, the lead reservoir, the eraser-propelling mechanism, and the side button are at least partly housed inside the barrel. The lead-propelling mechanism, the lead reservoir, and the eraser-propelling mechanism are prevented from rotating about the longitudinal direction relative to one another and relative to the side button, and the side button is prevented from rotating about the longitudinal direction relative to the barrel.

A side-knock type mechanical pencil comprising a body with a side-mounted knock button coupled to the body of the mechanical pencil and adapted to slidingly engage with a lead tube with a frustoconical hub for translating the motion of the knock button actuation to linear extension of the lead.

A side-knock type mechanical pencil comprising a body with a side-mounted knock button coupled to the body of the mechanical pencil and adapted to slidingly engage with a lead tube with a frustoconical hub for translating the motion of the knock button actuation to linear extension of the lead.

A side-knock type mechanical pencil comprising a body with a side-mounted knock button coupled to the body of the mechanical pencil and adapted to slidingly engage with a lead tube with a frustoconical hub for translating the motion of the knock button actuation to linear extension of the lead.

A side-knock type mechanical pencil comprising a body with a side-mounted knock button coupled to the body of the mechanical pencil and adapted to slidingly engage with a lead tube with a frustoconical hub for translating the motion of the knock button actuation to linear extension of the lead.

A mechanical pencil unit is provided which includes: a holding tube; a holder which is inserted into a front side opening portion of the holding tube and which protrudes forward from a front end of the holding tube, and moreover which is supported so as to be back and forth movable relative to the holding tube; a pencil lead delivering mechanism which delivers forward a pencil lead x inserted into the holder; and a movement direction conversion mechanism which causes the holder to go forward relative to the holding tube and the pencil lead x by using a force applied in a radial direction from the pencil lead x to the holder, wherein the pencil lead delivering mechanism is provided at a position further toward a rearward side than the holder and the movement direction conversion mechanism.

A mechanical pencil unit is provided which includes: a holding tube; a holder which is inserted into a front side opening portion of the holding tube and which protrudes forward from a front end of the holding tube, and moreover which is supported so as to be back and forth movable relative to the holding tube; a pencil lead delivering mechanism which delivers forward a pencil lead x inserted into the holder; and a movement direction conversion mechanism which causes the holder to go forward relative to the holding tube and the pencil lead x by using a force applied in a radial direction from the pencil lead x to the holder, wherein the pencil lead delivering mechanism is provided at a position further toward a rearward side than the holder and the movement direction conversion mechanism.

A mechanical pencil including: a body cylinder; a lead releasing unit configured to release a writing lead and having a rear region supported inside the body cylinder such that a front region thereof is flexurally deformable or tiltable inside the body cylinder; and a stretchable elastic body arranged between the lead releasing unit and a body cylinder, in which the lead releasing unit has a pressed portion on an outer circumferential surface of the front region, the body cylinder has a pressing portion in a front region, the pressing portion and the pressed portion abut on each other before the front region of the lead releasing unit is flexurally deformed or tilted, and the pressing portion causes the pressed portion to relatively move to the rear side with respect to the body cylinder when the front region of the lead releasing unit is flexurally deformed or tilted.

A mechanical pencil including: a body cylinder; a lead releasing unit configured to release a writing lead and having a rear region supported inside the body cylinder such that a front region thereof is flexurally deformable or tiltable inside the body cylinder; and a stretchable elastic body arranged between the lead releasing unit and a body cylinder, in which the lead releasing unit has a pressed portion on an outer circumferential surface of the front region, the body cylinder has a pressing portion in a front region, the pressing portion and the pressed portion abut on each other before the front region of the lead releasing unit is flexurally deformed or tilted, and the pressing portion causes the pressed portion to relatively move to the rear side with respect to the body cylinder when the front region of the lead releasing unit is flexurally deformed or tilted.