JPS6111017Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a structure for attaching and detaching a cap having a lid shaft having the same diameter to a writing instrument body having a right cylindrical outer shaft.

If the outer shaft of the main body and the lid shaft of the cap are made into a right cylindrical shape with the same diameter, there will be no steps when the cap is attached, creating a straight line and creating a simple and beautiful appearance, which is why it is often used in writing instruments such as fountain pens.
In order to make it possible to attach the cap to the rear end of the main body when writing, the rear end of the main body was formed with a small diameter corresponding to the thickness of the lid shaft, and the cap was fitted into the cap. The number of parts increased and the structure became complicated, and when the cap was attached to the tip of the main body, the small diameter part at the rear end spoiled the simple appearance. Therefore, a locking tube is made to protrude from the opening at the tip of the lid shaft of the cap, and an annular groove is provided on the rear end surface of the main body and at the connection between the large tip and the outer shaft, and the locking tube is inserted into this groove. Writing instruments have been put into practical use in which caps are attached to the front and rear ends of the main body by pressing against the inner surface of the outer shaft. However, this writing instrument has a problem in that it has an annular groove on the front and back, making it very unsightly.

Therefore, the present invention has been developed for a writing instrument in which a locking tube protruding from the tip opening of the lid shaft of the cap is press-fitted to the inner circumferential surface of the front and rear ends of the right cylindrical outer shaft. The shaft can be moved back and forth within a predetermined range within the outer shaft, and when the cap is attached to the tip of the main body when not writing, the locking tube presses the flange of the fore end, causing the inner shaft to retreat and move the rear end. part closes the rear end opening of the outer shaft, and when the cap is attached to the rear end of the main body during writing, the locking cylinder presses the rear end surface of the inner shaft, causing the inner shaft to move forward and close the flange at the tip. By closing the opening at the tip of the outer shaft, when attaching the cap to the front and rear ends of the main body, a simple straight line is created without any steps, and the annular groove is not visible from the outside. That is.

Embodiments of the present invention will be specifically described below with reference to the drawings.

First, to explain the writing instrument itself, there is a flange 2a on the rear outer peripheral surface of the tip 2 to which the pen body 1 is fixed.
An inner shaft 3 is screwed to the rear of the collar 2a. An ink cylinder 4 is housed within this inner shaft 3, and the ink inside this cylinder is transmitted to the pen body 1 through a pen core (not shown) in the tip 2, so that writing is possible. This inner shaft 3 is fitted into a right cylindrical outer shaft 5, and a vertical groove 3a of a predetermined length is provided on the outer surface of the inner shaft 3. The protrusions 5a are engaged in a press-contact state, and although they do not move back and forth under their own weight alone, they move back and forth by a predetermined length when pressed from the outside. Here, the outer diameters of the flange 2a of the large tip 2 and the rear end 3b of the inner shaft 3 are equal to the inner diameters of the tip opening and the rear end opening of the outer shaft 5, respectively, and when the inner shaft 3 is at the forward limit position, the flange The portion 2a closes the tip opening of the outer shaft 5, and the rear end portion 3b closes the outer shaft 5 when it is in the retraction limit position.
It is designed to close the rear end opening of. Next, the cap has a locking tube 7 fixed in a right cylindrical lid shaft 6 having the same diameter as the outer shaft 5, with its tip end protruding from the opening at the end of the lid shaft 6. This locking tube 7 has an annular projection 7a provided on its protruding portion that can be fitted into pressure contact with the inner peripheral surface of the tip and rear end of the outer shaft 5.
Its protruding length is equal to the movable distance of the inner shaft 3 within the outer shaft 5.

In the writing instrument main body and cap having the above structure, when the cap is attached to the tip of the main body when not writing, the tip edge of the locking tube 7 touches the flange 2a of the large tip 2, as shown in FIG. The inner shaft 3 is pushed back to the retraction limit position, and the rear end portion 3b closes the rear end opening of the outer shaft 5. At this time, the opening edge of the lid shaft 6 is
The device is placed in contact with the opening edge of the distal end without forming a step. Next, when attaching the cap to the rear end of the main body for writing, the leading edge of the locking tube 7 presses the rear end 3b of the inner shaft 3 to advance it to the forward limit position, as shown in FIG. The flange portion 2a closes the opening at the tip of the outer shaft 5, and at this time, the outer shaft 5 and the lid shaft 6 are also attached without forming a step.

In this way, the present invention is simple and beautiful because there is no step when attaching the cap to the tip and rear ends of the writing instrument body. A circular groove is provided,
Since these are not visible from the outside, it has the advantage that it can be finished more simply.

[Brief explanation of the drawing]

1 and 2 are sectional views showing an embodiment of the present invention. 1... Pen body, 2... Tip, 2a... Tsuba, 3
...Inner shaft, 4...Ink cylinder, 5...Outer shaft, 6...
Lid shaft, 7...Latching cylinder.

Claims (1)

[Scope of utility model registration request] An inner shaft housing an ink cylinder is connected to the rear end of the large tip, which has a pen body fixed to the tip, and this inner shaft is inserted into a right cylindrical outer shaft, which is the main body of the writing instrument, and the outer shaft. It consists of a cap with a locking tube protruding from the opening at the tip of the lid shaft, which has the same diameter as the shaft, and the cap is attached to the writing instrument body by fitting the locking tube into pressure contact with the inner peripheral surface of the tip and rear end of the outer shaft. In what is done,
The inner shaft can be moved back and forth within a predetermined range within the outer shaft, and when the cap is attached to the tip of the main body when not writing, the locking tube presses the flange of the tip, causing the inner shaft to retreat and then move back and forth. The end closes the rear end opening of the outer shaft,
When attaching the cap to the rear end of the main body when writing, the locking tube presses the rear end surface of the inner shaft, causing the inner shaft to move forward and the flange at the large tip to close the opening at the tip of the outer shaft. Features a removable writing cap structure.