JPS5837672Y2 - Knotsuku style pencil - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a so-called double-knock type mechanical pencil.

This type of so-called double-knock mechanical pencil is designed to perform two different functions by adjusting the knock stroke of the lead housing cylinder in two different sizes.

For example, as proposed in Utility Model Publication No. 51-22742, by adjusting the knock, the guide pipe at the lower end of the brush shaft can be switched between a free state in which it retracts with the lead, and a fixed state in which it does not retract with a light force, or Jikoko 46
As in the invention of No. 17449, the leading-out operation and the retracting operation of the lead are performed by adjusting the knock.

Switching between these two functions is performed by a feeding mechanism at the bottom of the pen shaft centered on the chuck.

However, with such double-knock type mechanical pencils, the two functions described above are switched only by the amount of pressure you press, so you have to be careful when operating the knock, and there is a risk that the function will turn off unexpectedly if you press too hard. There were inconveniences and uncertainties in operation, such as switching between switches and not being able to switch smoothly due to insufficient pressure.

Therefore, the present invention aims to provide a knock-type mechanical pencil that can reliably regulate knock strokes of two different sizes, thereby simplifying and ensuring operation.The structure of the mechanical pencil is as follows.

The present invention provides a knock-type mechanical pencil in which a lead storage cylinder having a chuck at the tip is inserted into the brush shaft so as to be elastically slidable therein, and the brush shaft can be moved relative to each other within a predetermined range in the circumferential direction. It is composed of an upper and a lower body that are rotatably connected, and a cylinder that fits inside and outside is connected to the upper body and the lower body, and of the inner cylinder and the outer cylinder, the inner cylinder has a
An elastic piece that can elastically swing inward and outward in the radial direction is provided, and between this elastic piece and the outer cylinder facing it, the elastic piece moves as the upper and lower bodies rotate relative to each other. An elastic piece swinging mechanism for swinging the piece in and out in the radial direction is provided, and
The knock-type mechanical pencil is characterized in that a stopper is provided at a predetermined position on the outer periphery of the lead housing cylinder, the stopper being able to lock onto the elastic piece when the elastic piece is swung inward.

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

1 is a brush shaft; 2 is an end tube that is detachably attached to the lower end of the brush shaft 1; 3 is a guide pipe that is provided on the end tube 2 so that it can move forward and backward; and 4 is a guide pipe that can be slid on the brush shaft 1. The core housing cylinder 4 has an internal core housing, and two different functions can be performed by knocking the core housing cylinder 4 with double strokes of large and small strokes.

The present invention can be applied to all mechanical pencils in which two different functions are achieved by the knock strokes of two different sizes, but in this embodiment, the knock strokes of the lead housing cylinder 4 are exemplifies a structure in which two functional states can be obtained: a free state in which the guide pipe 3 can move in and out together with the core 5, and a fixed state in which it cannot move in and out with a light force.

That is, as shown in FIG. 2, a tube 6 is connected to the lower end of the core housing cylinder 4, and a chuck 7 is provided at the lower end of the iron tube 6.

This tube 6 is slidably held by a cylinder 8 fixed to the lower end of the brush shaft, and a sliding ring 9 arranged on the outer periphery of the chuck 7 is removably fitted inside the lower part of the cylinder 8. It is supposed to be done.

Further, the end tube 2 is threadedly connected to the outer periphery of the flat end of the cylindrical body 8 that protrudes below the writing shaft 1.

A large diameter hole 10 and a small diameter hole 11 are formed vertically in communication with each other in the axial center of the end tube 2, and a guide pipe 3 is formed in the small diameter hole 11.
is loosely fitted so that it can slide freely.

A flanged protrusion 12 is formed at the upper end of the guide pipe 3, and a push tube 3a is fixed to the upper end surface.

On the other hand, the large diameter hole 10 has a flange-like protrusion 12 of the guide pipe 3.
A cylindrical member 13 is fitted loosely into the cylindrical member 1.
Projecting edges 1 are provided on the inner periphery of the upper and lower ends of 3, respectively.
4j5 is formed.

Of these, the upper protruding edge 14 does not allow the brim-shaped protrusion 12 of the guide pipe 3 to pass through, and the lower protruding edge 15 prevents the guide pipe 3 from passing when a large force is applied in the advancing (descending) direction. Only a small force allows the flanged protrusion 12 to pass, and a small force prevents the passage of the protrusion 12.

16 is a coil spring that elastically supports the core housing cylinder 4.

In this configuration, when the lead housing cylinder 4 is pressed through the cap 17, the lead housing cylinder 4 is lowered, and the chuck 7 at the lower end of the cylinder and the sliding ring 9 fitted onto the chuck 7 are also lowered together.

Even after the ring 9 hits the upper step of the large diameter hole 10 of the end cylinder 2 and stops descending, only the chuck 7 remains in the large diameter hole 10.
By expanding the guide pipe 3 to the zero position and pushing the guide pipe 3 through the push tube 3a with the lower end of the chuck, the pipe 3 is pushed out together with the core 5.

Next, when the pressure on the core housing cylinder 4 is released, the chuck 7 is retracted by the coil spring 16, leaving the core 5 behind.

By repeating this operation, writing is performed with the tip of the lead 5 slightly protruding from the guide pipe 3, and as the lead 5 wears out, the guide pipe 3 also retracts at the same time, and the pipe 3
Writing can be performed continuously without performing an operation of feeding out the lead until the lead is retracted into the end tube 2.

When the core housing cylinder 4 is pressed in a small stroke with a normal light force in this way, the brim-shaped protrusion 12 of the guide pipe 3 freely strokes between the upper and lower protruding edges 14 and 15 in the cylindrical member 13.

This state is the so-called free (sliding) state of the guide pipe 3.

On the other hand, when the core housing cylinder 4 is pushed strongly with a large stroke, the brim-like protrusion 12 of the guide pipe 3 passes over the lower protrusion 15,
The guide pipe 3 protrudes greatly (the position shown by the imaginary line in FIG. 2).

When the pressure on the core housing tube 4 is released in this state, the brim-shaped protrusion 12 is locked to the lower side of the lower protrusion 15, so that the guide pipe 3 no longer retreats with a small force.

This state is the so-called fixed state of the guide pipe 3.

By setting it in this fixed state, it is possible to eliminate inconveniences such as only the guide pipe 3 touching the ruler and retracting and the lead 5 breaking when drawing a line with a ruler applied during drafting.

In such a configuration, in order to prevent the lead storage tube 4 from being pushed too much or not enough, resulting in a functional state opposite to the desired one or not being switched smoothly, the mechanical pencil of the present invention has the following features. The structure is as follows.

First, the brush shaft 1 is composed of an upper body 18 and a lower body 19 that are separate from each other.

An inner cylinder 20 is deviated from the upper end of the lower body 18 so as to protrude above the main body 18, and an outer cylinder 21 into which the inner cylinder 20 can be fitted is fixed inside the flat end of the upper body 18. .

In addition, dowels 22 and 22 are provided on the outer peripheral surface near the upper end of the inner cylinder 20.
A bulge is formed.

Thus, the inner cylinder 20 and the outer cylinder 21 are fitted inside and outside,
In addition, the dowel 22 of the inner cylinder 20 that has passed through the outer cylinder 21 is removed and locked to the upper end of the outer cylinder, so that the upper and lower main bodies 18 and 19 are brought into contact with each other, with their end surfaces abutting each other.
They are connected to each other so that they can rotate in the circumferential direction.

The inner tube 20 is screwed onto the lower body 19 as shown, and the outer tube 21 is press-fitted or adhered to the upper body 18, but these fixing means can be selected as appropriate.

A pair of elastic pieces 23 and 23 are formed in the inner cylinder 20 by making U-shaped cuts at two symmetrical locations on the circumference.

This elastic piece 23.23 is formed to be able to elastically swing in and out in the radial direction of the inner cylinder with its lower part as a fulcrum, and the outer surface of this elastic piece 23.23 has a conical protrusion 24. 24
is provided.

Note that the elastic piece 23 may be formed by attaching another plate spring material to the inner cylinder 20.

Further, the protrusion 23 may be formed by bulging a predetermined portion of the elastic piece 23 outward as shown in the figure, or may be formed by bulging the same portion into a thick shape.

Further, the outer cylinder 21 has a protrusion 24.2 of the elastic piece 23.23.
Elongated engagement grooves 25, 25 are provided along the circumferential direction at two locations on the circumferential wall corresponding to 4, and the engagement grooves 25 and the protrusion 24 constitute an elastic single swing mechanism.

This retaining groove 25.25 is shaped like a tapered hole whose width changes along the circumferential direction.

That is, one end 25a in the circumferential direction has a wide width so that the protrusion 24 of the elastic piece 23 can completely engage with the base, and the width gradually decreases from the end 25a until the opposite end. 25b (hereinafter, this end 25b will be referred to as the release position and the other end 25a will be referred to as the locking position), the protrusion 2
It is formed with such a narrow width that only the apex portion of No. 4 can be engaged.

Note that the engagement position 25 a and the disengagement position 25
The end face of b is shaped like an arc, and is located at the disengagement position 25.
b is shaped like a keyhole with a particularly narrow front part.

In this way, the engagement state of the protrusion 24 is stabilized at the same positions 25a and 25b, and a clear feeling and amount of engagement can be obtained during engagement, and furthermore, at the engagement release position 25b, the unexpected situation of the protrusion 24 is prevented. Relapse can be prevented.

Note that the engagement grooves 25, 25 are each formed in a range of about 90 degrees from each other in the circumferential direction.

On the other hand, a flange-shaped stopper 26 is provided on the outer circumferential surface of the core housing cylinder 4 at a predetermined distance behind the elastic piece 23 in the non-knocked state position.

This stopper 26 may be formed integrally with the core housing cylinder 4, or may be press-fitted with a separate brim-like body.

Alternatively, the core housing cylinder 4 can be shaped like a stepped shaft, and the stepped portion can be used as a stopper.

In addition, as shown in the figure, on the surfaces of the ends of the upper and lower main bodies 18 and 19 that are joined to each other, there is a state in which the protrusion 24 of the elastic piece 23 engages with the engagement position 25a of the engagement groove 25, and a state in which the protrusion 24 of the elastic piece 23 engages with the engagement position 25a of the engagement groove 25, and a state in which the engagement is released. An arrow indicating the state position to engage position 25b and Fix
, 5lide are marked.

As described later, in the Fix position, which means fixing, the protrusion 2
4 engages with the engagement position 25a, and as a result, the guide pipe 3 can be set in a fixed state in which it cannot be retracted with a light force.

Further, in the 5ride position, the protrusion 24 is in the disengagement position 25.
As a result of engaging with b, the guide pipe 3 can be held in the free state described above.

Then, the upper and lower main bodies 18 and 19 are aligned with the above-mentioned Fix position, and the protrusion 24 is inserted into the engagement groove 2 as shown in FIG.
When the elastic piece 23 is engaged in the engagement position 25a of
No inward pressing force is applied to the iron piece 23, and the iron piece 23 is in a position parallel to the outer cylinder 21 and the core housing cylinder 4.

Therefore, the stopper 26 of the core housing cylinder 4 can freely slide within the inner cylinder 20 without being restricted by the elastic piece 23.

Therefore, by strongly pressing the core housing tube 4 (with a large stroke) in this state, the guide pipe 3 can be set in the fixed state described above.

In this case, in order to determine the stroke end of the core housing cylinder 4, a stopper (not shown) may be provided at a predetermined position on the inner peripheral surface of the inner cylinder 20.

Next, when the upper and lower main bodies 18 and 19 are relatively rotated in the circumferential direction and adjusted to the 5lide position, the protrusion 24
moves in the circumferential direction of the engagement groove 25 and moves to the engagement release position 25b where the amount of engagement is the smallest with respect to the groove 25.

In this case, as shown in FIG. 7, the elastic piece 23 receives an inward pressing force, and its upwardly directed tip faces the movement path of the core housing cylinder 4.

Therefore, when the core housing cylinder 4 is knocked in this state, the stopper 26 always hits the elastic piece 23 with a constant stroke.
Further decline can be stopped.

Therefore, even if the core housing cylinder 4 is pushed strongly, the guide pipe 3 is never changed to the fixed state and is maintained in the free state.

In this way, in this mechanical pencil, the sliding stroke of the lead housing cylinder 4 can be selectively regulated in two ways, both large and small, at a location other than the feeding mechanism at the bottom of the pen shaft.

Therefore, according to this mechanical pencil, there is no need to pay extra attention to the pressing force, and it is sufficient to mechanically press the button until it is regulated as described above, making the knocking operation easier.

Further, there is no fear that the functional state will change unexpectedly due to excessive pressing, and the desired functional state can be reliably obtained.

In the above embodiment, the inner cylinder 20 provided with the elastic piece 23 with a protrusion is placed on the lower main body 19 side, and the outer cylinder 2 provided with the engagement groove 25 is placed on the lower body 19 side.
1 is provided on the upper main body 18 side, however, the same effect as described above can be obtained even if the inner cylinder 20 is provided on the upper main body 18 side and the outer cylinder 21 is provided on the lower main body 19 side.

In addition, a protrusion 24 and an engagement groove 25 constituting the elastic single swing mechanism are also provided.
Regarding this, in the above embodiment, the elastic piece 23 is provided with the protrusion 24, but the protrusion 24 may be provided on the inner peripheral surface of the outer cylinder 21, and the engagement groove 25 may be provided on the elastic piece 23.

Further, in the above embodiment, the engaging groove 25 is formed in a tapered shape whose width gradually changes, but the technique of the present invention may also be such that the width is made different only at both end portions in the circumferential direction, and the middle portion is formed to have a constant width. belongs to the range.

Further, regarding this retaining groove 25, an embodiment shown in FIG. 8 can also be adopted.

For example, when forming the engagement groove 25 in the outer cylinder 21, by forming the engagement groove 25 in the shape of a concave groove along the circumferential direction on the inner peripheral surface of the outer cylinder and gradually changing the depth,
An engagement position 25a and a disengagement position 25b are formed at both ends.

Even when this embodiment is adopted, the effect of the elastic single swing mechanism by the protrusion 24 and the engagement groove 25 can be obtained in the same way as in the case of the elongated engagement groove 25 described above.

Also in this embodiment, only the opposite end portions of the concave engagement groove 25 may be formed to have different depths.

Furthermore, this protrusion 24, the engagement groove 25, and the elastic piece 2
In the above-mentioned embodiment, two sets of the number 3 are provided, but it may be provided as one set.

On the other hand, in each of the above embodiments, the protrusion is moved in the circumferential direction inside the engagement groove to switch between the engagement position and the disengagement position. A hole or a round recess is formed, and when the projection engages with this round hole or recess, it is in the locked position, and in all other regions, that is, in the area close to 360 degrees in the circumferential direction where the projection comes out from the round hole or recess. It may be configured to be in the uncoupled position.

As described above, according to the present invention, in a knock-type mechanical pencil in which two different functional states can be obtained by two different knock operations, the two large and small knock strokes of the lead housing cylinder are controlled by the lead feeding mechanism. Since we have made it possible to selectively and reliably regulate the knock operation at a different location, there is no need to put extra effort into the knock operation, making it easier to operate and ensuring the desired functional state is achieved. It is something.

In addition, the knock stroke restriction position can be easily changed by simply rotating the upper and lower bodies relative to each other, and thus has extremely high practical value.

[Brief explanation of the drawing]

The figures show an embodiment of the present invention, with Figure 1 being an overall perspective view and Figure 2 being an overall perspective view.
The figure is an enlarged longitudinal cross-sectional view of the lower part of the pen shaft, Fig. 3 is an enlarged side view showing a cross section of the main part, Fig. 4 is an exploded perspective view, Fig. 5 is an enlarged side view of the outer cylinder, and Fig. 6 is an enlarged side view of the main part. A perspective view of the main parts to explain the operation when a large knock stroke is possible, the mouth is the same sectional view,
FIG. 7A is a perspective view for explaining the operation when a small knock stroke is possible, the mouth is a sectional view of the same, and FIG. 8 is a partial sectional view showing another embodiment of the retaining groove. 1...Brush barrel, 4...Lead storage tube, 5...
... Core, 7 ... Chuck, 18 ...
・Upper body, 19...Lower body, 20...
... Inner cylinder, 21 ... Outer cylinder, 23 ... Elastic piece, 24 ... Protrusion of elastic piece rocking mechanism, 25 ...
...Engaging groove, 25a, 25b...
・Both ends in the circumferential direction of the engagement groove, 26... Stoppers.

Claims (1)

[Claims for Utility Model Registration] (1) A knock-type mechanical pencil in which a lead storage cylinder having a chuck at the tip is inserted into the brush shaft so as to be able to slide elastically thereinto, the brush shaft being moved in the circumferential direction. It consists of an upper and a lower body connected so as to be able to rotate relative to each other within a predetermined range, and a tube that fits inside and outside is connected to the upper and lower bodies, and the inner tube and the outer tube are connected to each other. Among them, an elastic piece that can elastically swing in and out in the radial direction is provided in the inner cylinder, and
An elastic piece swinging mechanism is provided between the elastic piece and the outer cylinder facing it, for swinging the elastic piece in and out in the radial direction with the relative rotation of the upper and lower main bodies, and a knock type % type % characterized in that a stopper is provided at a predetermined position on the outer periphery of the core accommodating cylinder so as to be able to engage the elastic piece in a state in which the elastic piece is swung inwardly. An elastic piece swinging mechanism is constructed by providing a protrusion on one side of the elastic piece and the outer cylinder circumferential wall facing the elastic piece, and a long hole-shaped retaining groove along the circumferential direction on the other side, and the retaining groove includes: A knock-type mechanical pencil according to claim 1, characterized in that the widths of both side portions in the circumferential direction are made different so that the engagement depth of the protrusion changes in size on both side portions in the circumferential direction. 3. An elastic piece rocking mechanism is constructed by providing a protrusion on one side of the elastic piece and the outer cylinder circumferential wall facing the elastic piece, and a groove-shaped engagement groove along the circumferential direction on the other side, and the engagement groove is a knock-type sharpener according to claim 1 of the utility model registration claim, characterized in that the depths of the protrusions on both sides in the circumferential direction are different so that the engagement depth of the protrusions varies in size. Penzino L0