A pressurized writing implement includes a shaft tube capable of housing therein a refill filled with a writing implement ink composition. The pressurized writing implement further includes a pressurizing mechanism that applies a pressure to the writing implement ink composition, the pressurized writing implement being capable of switching a writing state in which a front end part of the refill projects from a front end opening of the shaft tube, and a not-writing state in which the front end part of the refill is retracted from the front end opening of the shaft tube. The pressurized writing implement further includes a pressurizing-force adjusting mechanism that adjusts the pressure.

A pressurized writing implement includes a shaft tube capable of housing therein a refill filled with a writing implement ink composition. The pressurized writing implement further includes a pressurizing mechanism that applies a pressure to the writing implement ink composition, the pressurized writing implement being capable of switching a writing state in which a front end part of the refill projects from a front end opening of the shaft tube, and a not-writing state in which the front end part of the refill is retracted from the front end opening of the shaft tube. The pressurized writing implement further includes a pressurizing-force adjusting mechanism that adjusts the pressure.

A writing instrument may include an elongated tubular casing, an elongated writing medium cartridge and a tubular elastic spring element. The tubular elastic spring element comprises a first portion and a second portion. The second portion comprises a wall comprising a plurality of apertures.

A writing instrument may include an elongated tubular casing, an elongated writing medium cartridge and a tubular elastic spring element. The tubular elastic spring element comprises a first portion and a second portion. The second portion comprises a wall comprising a plurality of apertures.

A thermochromic writing instrument including a writing body, storing a thermochromic ink therein, stored in a barrel; an operation body provided in the barrel to be operated to longitudinally move the writing body; a nib of the writing body configured to be capable of appearing from a front end of the writing instrument, wherein the writing instrument 1 further includes a friction unit, for rubbing handwriting in the thermochromic ink and capable of thermally changing the color of the handwriting by frictional heat generated at that time, and at least one clip body as the operation body, the friction unit 10 is provided at a rear end of the barrel, and the clip body is provided in an area other than the rear end of the barrel.

A thermochromic writing instrument including a writing body, storing a thermochromic ink therein, stored in a barrel; an operation body provided in the barrel to be operated to longitudinally move the writing body; a nib of the writing body configured to be capable of appearing from a front end of the writing instrument, wherein the writing instrument 1 further includes a friction unit, for rubbing handwriting in the thermochromic ink and capable of thermally changing the color of the handwriting by frictional heat generated at that time, and at least one clip body as the operation body, the friction unit 10 is provided at a rear end of the barrel, and the clip body is provided in an area other than the rear end of the barrel.

A writing instrument, in particular a pen, comprises a housing comprising a front barrel and a rear barrel, the front barrel having a front opening, two or more cartridges for storing colorants or inks, each cartridge having a writing tip, at least one actuator for selectively moving one of the cartridges within the housing so that the writing tip of a selected cartridge extends through the front opening of the front barrel, and a cartridge guide member which is designed to guide the movement of the cartridges within the housing. The front barrel and to the cartridge guide member are designed to be removed from the rear barrel for replacing one or more of the cartridges. In particular, the front barrel and the cartridge guide member may be removed from the rear barrel while the cartridge guide member may remain mounted to the front member at the same time.

A writing instrument, in particular a pen, comprises a housing comprising a front barrel and a rear barrel, the front barrel having a front opening, two or more cartridges for storing colorants or inks, each cartridge having a writing tip, at least one actuator for selectively moving one of the cartridges within the housing so that the writing tip of a selected cartridge extends through the front opening of the front barrel, and a cartridge guide member which is designed to guide the movement of the cartridges within the housing. The front barrel and to the cartridge guide member are designed to be removed from the rear barrel for replacing one or more of the cartridges. In particular, the front barrel and the cartridge guide member may be removed from the rear barrel while the cartridge guide member may remain mounted to the front member at the same time.

The present invention includes a shaft cylinder having an opening at a front end thereof, a tip holder movable in an axial direction of the shaft cylinder, a tip projectable and retractable in conjunction with a movement of the tip holder, an annular member fitted on the tip holder and axially movable, and an elastic member connecting the tip holder and the annular member so that they are movable relatively to each other. A contact surface tapered toward the front end is formed on an outer periphery of the annular member. A cutout reduces an inner diameter of the annular when a load is received by the contact surface. A guide surface is formed on the part of the inside surface of the shaft cylinder. The contact surface receives the load from the guide surface in conjunction with the movement of the tip holder toward the front end side.

The present invention includes a shaft cylinder having an opening at a front end thereof, a tip holder movable in an axial direction of the shaft cylinder, a tip projectable and retractable in conjunction with a movement of the tip holder, an annular member fitted on the tip holder and axially movable, and an elastic member connecting the tip holder and the annular member so that they are movable relatively to each other. A contact surface tapered toward the front end is formed on an outer periphery of the annular member. A cutout reduces an inner diameter of the annular when a load is received by the contact surface. A guide surface is formed on the part of the inside surface of the shaft cylinder. The contact surface receives the load from the guide surface in conjunction with the movement of the tip holder toward the front end side.