JP2905047B2 - Cutting tool - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting tool for cutting an object with two cutting blades such as scissors and a push cutter.

[0002]

2. Description of the Related Art Scissors are an example of a general cutting device. In the scissors, two blades are relatively rotated about a fulcrum pin as a rotation center to cut an object such as paper. The action of this cutting is specifically based on the shearing force of the two blades against the object to be cut, and the shearing portion moves as the two blades close, and as a result of continuous shearing, Is to be cut. However, the cutting effect is further improved not only by the shearing force but also by a pulling action such as when cutting sashimi with a kitchen knife. Therefore, as disclosed in Japanese Utility Model Publication No. 168471/1985, a technique is disclosed in which both blades shear an object and at the same time one blade slides to pull the object. .

A technical feature of the scissors disclosed in the publication is that two support pins are loosely fitted in two separately formed holes, respectively.

[0004]

However, in such a type in which two holes are formed, the alignment between the holes and the pins becomes very delicate, which is very troublesome in design and manufacture. know. That is, as shown in FIG. 15, a first elongated hole 30 extending in the blade edge direction,
A second long hole 32 having an angle of about 45 degrees with respect to the first long hole 30 is formed at the position of the pivot of the scissors.
Here, the relative angle between the holes 30 and 32 is very delicate. That is, if the angle is too large, even if the blade bodies 34 and 35 are relatively rotated, the first fulcrum pin 31 in the first long hole 30 moves against the movement of the second fulcrum pin 33 in the second long hole 32.
Of the fulcrum pin 31 (movement in the vertical direction in the figure) is reduced. That is, the pull-off effect is not sufficiently exhibited. On the other hand, if the angle is too small, the second fulcrum pin 33 naturally collides with the side of the second long hole 32, so that it cannot even be used as scissors. How to adjust this angle has to be cautious because it affects the distance and length between the long holes 30 and 32.

[0005] Setting the distance between the holes 30 and 32 is also troublesome. In FIG. 15, the distance between the holes 30 and 32 is inversely proportional to the amount of rotation of the blades 34 and 35. That is, both holes 3
The more the 0 and 32 are separated from each other, the narrower the opening angle of the cutting edge for the same amount of rotation of the blade bodies 34 and 35 becomes. Therefore, in order to secure the opening angle of the cutting edge, the shorter the distance P, the better. However, from the viewpoint of strength, the distance P needs to be maintained to some extent. However, in order to increase the distance P and sufficiently secure the opening angle of the cutting edge, it is necessary to lengthen the second long hole 32. Then, it is necessary to increase the width of the blades 34 and 35 in the vicinity of the fulcrum pin, which is very wasteful. In addition, the mechanical upper blades 34, 35
In order to completely open the second slot 32 in FIG.
Must be advanced to near the Q line. This point also caused the width to be increased. Furthermore,
In order to reduce the width of the blades 34 and 35 near the fulcrum pins as much as possible, the second fulcrum pins 33 tend to be thin, and the scissor assembling operation also requires skill.

As described above, the length P and the distance P
Therefore, the design and processing have been extremely labor intensive in conjunction with the adjustment of the angle. Furthermore,
Since two separate holes 30 and 32 are formed, the finish grinding inside the holes must also be performed separately, which complicates the process.

In the pulling-off operation, the first blade body slides with respect to the second fixed blade body to cut an object to be cut. If the cutting is performed while pulling the object to be cut, the cutting can be performed more smoothly and the load on one blade is reduced, so that the life of the scissors is extended.

The invention of claim 1 solves the problem of the conventional cutting tools such as scissors of the type of cutting and cutting at a stretch. An object of the present invention is to provide a cutting tool that can be easily designed and can smoothly cut a workpiece by sliding a blade body without requiring skill in processing. Another object of the present invention is to provide a cutting tool that can be cut more smoothly and has a long lasting sharpness in a conventional cutting tool such as scissors of the type that cuts and cuts.

[0009]

In order to achieve the above object, according to the first aspect of the present invention, a first blade having a cutting edge is provided with an elongated hole having a bent portion at a central portion thereof. The second with
A pair of fulcrum pins protruding from the blade body are regulated at the distance between the bent portion and the end of the long hole, and the two fulcrum pins are loosely fitted into the same hole to support the both blade bodies. The gist of the present invention is to dispose the slide portion so as to slide between both ends of the elongated hole and the bent portion alternately at the bent portion in synchronization with the cutting operation of the body.
According to the second aspect of the present invention, the first blade having the cutting edge is provided with a first elongated hole having a bent portion at the center, and the second blade having the cutting blade is provided with the first elongated hole. A second elongated hole having substantially the same size as the elongated hole formed in the blade body and having a bent portion bent in the opposite direction is formed, and a pair of fulcrum pins is provided between the bent portion and the end of the elongated hole. It is regulated at intervals and loosely fits into both long holes to support the two blades, and both fulcrum pins are synchronized with the cutting operation of both blades, and the ends of the long holes and the bent The gist is that they are arranged to slide.

[0010]

According to the above construction, according to the first aspect of the present invention, the pair of fulcrum pins always maintain the distance between the bent portion and the end of the elongated hole as the two blades move relative to each other. To move.
If the first fulcrum pin is located at the end in the slot, the second
Is located near the bent portion. As the two blades open or close due to the relative rotation of the two blades, the first
The fulcrum pin moves from the end position to the bent portion while sliding in the elongated hole. On the other hand, the second fulcrum pin moves while sliding from the vicinity of the bent portion to the end in the opposite direction. Then, the first blade body slides forward or backward with respect to the second blade body, and simultaneously cuts and cuts the object to be cut.

According to the second aspect of the present invention, the pair of fulcrum pins always maintain the distance between the bent portion and the end of the long hole in the long hole formed in the both blades with the relative rotation of the two blades. Moving. Both slots rotate with both blades at always symmetrical positions with both pins in between. The positional relationship between the long hole and both pins when the blade body rotates is the same as the operation of the first aspect. Since the long holes are bent in opposite directions, the sliding directions when the blade body is rotated are opposite to each other. Therefore, the first
When the blade body advances, the second blade body moves backward, and conversely, the first blade body moves forward.
When the second blade body retreats, the second blade body advances.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the cutting tool of the present invention is applied to scissors will be described below with reference to the drawings. (First Embodiment) As shown in FIGS. 1 to 4, the scissors 1 have a main body composed of a first blade body 3 and a second blade body 5,
The two blades 3 and 5 are pivotally mounted on pivot pins 8 and 9 as a center of rotation. The first blade body 3 is composed of a trunk 6 having a U-shaped bent portion 6a and a handle 7 made of synthetic resin fixed to a base end of the trunk 6. The body portion 6 is gradually narrowed from the bent portion 6a toward the distal end, and the distal end has a pointed shape. A single-edged cutting blade 2 is formed on one side of the body 6 ahead of the bent portion 6a. A long hole 10 through which the fulcrum pins 8 and 9 are inserted is formed through the bent portion 6a. The elongated hole 10 is formed by being bent at a right angle at a bent portion 10c at the center thereof. The first hole 10a extends in the tip direction of the body 6 with the bent portion 10c as a boundary, and the second hole 10b is formed. The torso 6 extends to the side. Both ends of the long hole 10 are formed in a semicircular shape. The handle 7 has an insertion hole 17 through which the thumb is inserted when the handle 7 is used.

The second blade 5 has a substantially straight body 12.
And a synthetic resin handle 13 fixed to the base end of the body 12
It is composed of The body 12 is gradually narrowed toward the tip, and the tip is pointed. A single-sided cutting blade 4 corresponding to the cutting blade 2 of the first blade body 3 is formed on a side portion of about two thirds of the tip side of the body portion 12. Second
A pair of circular holes 15 and 16 for inserting the fulcrum pins 8 and 9 are provided in front and rear of the blade body 5 near the center of the blade body 5. Both circular holes 15 and 16 are formed at intervals corresponding to the distance between the bent portion 6a of the elongated hole 10 and the end of the first hole 10a or the second hole 10b.

The two blades 3 and 5 are overlapped with each other so that the cutting blades 2 and 4 face each other, and are pivotally mounted by fulcrum pins 8 and 9. The two fulcrum pins 8, 9 are composed of heads 8a, 9a and trunks 8b, 9b. Both fulcrum pins 8,
9 are provided with elongated holes 10
Is inserted so as to be in a loosely fitted state. The torso portions 8b, 9b protruding from the long holes 10 are provided with the circular holes 15,
16 are inserted. Furthermore, the tips of the trunks 8b, 9b protrude outward from the second blade 5, so that the blades 3, 5 are supported by the trunks 8b, 9b of the fulcrum pins 8, 9. The tips of the body parts 8b, 9b are pressed and crushed to prevent the fulcrum pins 8, 9 from falling off from the blades 3, 5.

More specifically, both fulcrum pins 8 and 9 and circular hole 1
The positional relationship between the long holes 10 and the long holes 10 and the two blades 3 and 5 will be described. First, both fulcrum pins 8 and 9 are attached to their body portions 8b and 9
Since b is inserted into the circular holes 15 and 16 of the second blade body 5, the fulcrum pins 8 and 9 are always at a fixed position with respect to the second blade body 5. That is, the movement of the second blade 5 and the two fulcrum pins 8,
The movement of 9 is synchronous. As shown in FIG. 2, when both blades 3 and 5 are closed, the fulcrum pin 8 on the front side is located at the end of the first hole 10a in the elongated hole 10 and the fulcrum on the rear side. The pin 9 is located at the bent portion 10c.
On the other hand, when both blades 3 and 5 are half-opened as shown in FIG.
a and the second hole 10b. In addition, as shown in FIG. 4, when both blades 3 and 5 are fully opened, the fulcrum pin 8 on the front side is located at the bent portion 10c and the fulcrum pin 9 on the rear side is the second hole. 10
b.

A slot 10 is hidden between the heads 8a, 9a of the fulcrum pins 8, 9 and the first blade body 3 to prevent the fulcrum pins 8, 9 from rattling with each other. Washer 20 is fitted. The handle 13 has an insertion hole 18 through which a forefinger, a middle finger, and the like are inserted during use.

Next, the scissors 1 of the present embodiment configured as described above are used.
The operation of will be described. The fingers are hung on the insertion holes 17 and 18 of the handles 7 and 13 of the scissors 1, and the blades 3 and 5 are gradually rotated from the closed state in FIG. First opening of the blades 3, 5 is started the fulcrum pin 8 on the front side on the edge portion of the first hole portion 10a as the pivot center P _1.
Then, as the two blades 3 and 5 are opened, the fulcrum pin 8 on the front side is opened.
Starts sliding backward in the first hole 10a, while the rear fulcrum pin 9 located in the bent portion 10c is moved to the second position.
To the side of the hole 10b. In the substantially half-open state, the fulcrum pins 8 and 9 move to the intermediate positions between the first hole 10a and the second hole 10b, respectively, as shown in FIG. That is, the fulcrum pin 8 on the front side initially turning is there was a rotation center P ₁ position, the fulcrum pin 8 in this stage so that the shift in the P ₂ position. In other words, the first blade body 3 has slid forward (toward the edge of the blade) relative to the second blade body 5 by the shifted length (P ₁ -P ₂ ).

When the blades 3 and 5 are fully opened as shown in FIG. 4, the front fulcrum pin 8 moves to the bent portion 10c, and the rear fulcrum pin 9 becomes the second fulcrum pin 9 as shown in FIG. It reaches the end of the hole 10b. Supporting pin 8 in this stage is moved from the initial position P ₁ to position P ₃ of the bent portion 10c,
The first blade body 3 has slid relatively to the front side by the maximum amount. Next, an object to be cut such as paper is placed between the opened blades 3 and 5, and the blades 3 and 5 are closed again. Then, contrary to the above, the first blade body 3 slides rearward relative to the second blade body 5. The object to be cut is subjected to the shearing action of the two cutting blades 2 and 4 and the pulling action of the first blade body 3 at the same time, whereby smoother cutting is performed.

By configuring as in the first embodiment,
The following effects are obtained. 1) Since the two fulcrum pins 8 and 9 move in one long hole 10, it is not necessary to set the moving distance of the fulcrum pin on the handle side larger than in the conventional scissors having two holes. That is,
Since only one bent long hole 10 is formed, it is not necessary to increase the width of the blade bodies 3 and 5 near the fulcrum pins 8 and 9. Since the first blade body 3 is slidable with respect to the second blade body 5, a pulling action occurs during the cutting operation, and smooth cutting can be performed.

2) Only one long hole 10 needs to be formed as compared with the conventional scissors having two holes, so that the design and processing become extremely easy, and the work of grinding and finishing the periphery of the hole is reduced. 3) When the blade bodies 3 and 5 are closed, the two fulcrum pins 8 and 9 are exactly fitted between the end of the first hole 10a and the bent portion 10c. Therefore, rattling of the blade bodies 3 and 5 in the front-rear direction is suppressed. In addition, since the long hole 10 is formed at a right angle, the fulcrum pin 9 is prevented from being accidentally moved from the position of the bent portion 10c in the direction of the second hole 10b. That is, since the fulcrum pin 9 has a circular cross section, the bent portion 10c is formed.
The point of contact with the side wall of the scissors may cause the scissors 1 to be inadvertently opened due to rolling even at a slight obtuse angle. Right angle,
Alternatively, there is no danger if the angle is set so as not to hinder the rotation of the blades 3 and 5.

4) The spacing between the two fulcrum pins 8 and 9 is regulated in advance by the washer 20, so that the operation of mounting the two fulcrum pins 8 and 9 in the long hole 10 can be easily performed. In addition, since the long hole 10 is completely covered by the washer 20, the user cannot know how the two fulcrum pins 8 and 9 operate, thereby attracting interest and inspiring purchase.
Moreover, the scissors 1 also hide the oblong hole 10 in appearance, and can prevent a foreign object from entering the oblong hole 10 and causing malfunction. Further, dust hardly accumulates in the long hole 10. (Second Embodiment) A second embodiment will be described with reference to FIGS. In the first embodiment, the long hole 10 is formed in the first blade body 3, and the second blade body 5 is provided with circular holes 15 and 16. That is, the long hole 10 was formed only in one blade body 3. As shown in FIG.
Alternatively, the elongated hole 19 may be formed. In this embodiment, the basic members are the same as those in the first embodiment, and therefore only the differences will be described.

The elongated hole 19 of the second blade body 5 (hereinafter referred to as a second elongated hole 19) is the same as the elongated hole 10 of the first blade body 3 (hereinafter referred to as a first elongated hole 10). The first hole 19a extends toward the front end of the body 12 with the bent portion 19c as a boundary, and the second hole 19b extends to the side of the body 12 at the bent portion 19c. Extending. The second long hole 19 has a bent portion 19c which is bent just in the opposite direction to the first long hole 10. The distance between the two fulcrum pins 8 and 9 is regulated by two washers 20 arranged outside the two blades 3 and 5. Unlike the first embodiment, the circular hole 15,
Because there is no 16, the washers 20 are arranged on both sides of the two blades 3 and 5.

Next, the operation of the scissors 1 of this embodiment will be described. In principle, the first blade body 3 moves in the same manner with respect to the two fulcrum pins 8 and 9 as in the first embodiment. The second blade body 5 operates symmetrically with the first blade body 3 with both the fulcrum pins 8 and 9 interposed therebetween. As shown in FIG. 6, in a state where both the blades 3 and 5 are closed, the first hole 10 a of the first long hole 10 and the first hole 19 a of the second long hole 19 overlap, The two fulcrum pins 8 and 9 are located at the ends of the first holes 10a and 19a and the bent portions 10c and 19c, respectively. When the blades 3 and 5 are released from this state, the blades 3 and 5 gradually move forward (toward the blade edge) with respect to the initial rotation position.
The slide will be advanced. Both slots 10, 19
Always rotates around the fulcrum pins 8 and 9 so as to be symmetrical. 7 and 9 show the blade bodies 3 and 5 in a half-open state.

The half-opened state is further opened, and when it is completely opened, it moves to a position rotated by 90 degrees with respect to the positions of the long holes 10 and 19 in FIG. 6 as shown in FIG. . That is, the second hole 10b of the first long hole 10 and the second hole 19b of the second long hole 19 overlap. In this state, the two blades 3, 5 have been slid forward a maximum amount when viewed from the initial closed position. Next, an object to be cut such as paper is placed between the opened blades 3 and 5, and the blades 3 and 5 are closed again. Then, both blades 3, 5 will slide backward this time,
The blades 3 and 5 cut the object while applying a pulling action from both sides of the cutting blades 2 and 4 to the object.

By configuring as in the second embodiment,
The following effects are obtained. 1) Since cutting is performed by applying a pulling action from both sides of the object to be cut, the cutting is performed more smoothly, the problem of the object being bitten between the two blades 3 and 5 is reduced, and sharp scissors are used. 1 is provided.

2) Since the object to be cut is cut off from both sides, the load on the cutting blades 2 and 4 of one of the blade bodies 3 and 5 is reduced, and the sharpness is prolonged. Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and may be configured as follows, for example, without departing from the gist of the invention.

1) In each of the above embodiments, the long hole 10 is formed by being bent at a right angle. However, the angle may be an acute angle or an obtuse angle. In other words, according to the first embodiment, if the play between the long hole 10 and the fulcrum pins 8 and 9 increases , the two blade bodies are formed even if the angle between the first hole 10a and the second hole 10b is slightly acute. 3, 5 can rotate. Also, when the obtuse angle is set, the two blades 3 and 5 are easily opened, but there is no problem in the pulling action.

2) The arrangement position of the long hole 10 and the corresponding positions of the circular holes 15 and 16 may be formed at positions rotated with respect to the positions in the above embodiment as shown in FIG. .

3) In the above embodiment, the bent portion 10 of the long hole 10
Although the inner circumferential side of c was bent at a right angle exactly,
As shown in FIG. 1, it may be formed in a curved shape. 4) Further, as shown in FIG. 12, the fulcrum pins 8 and 9 may be connected by a connecting portion 23 to form an integral member. In this way, when assembling the scissors, the circular hole 1
It becomes easy to insert both fulcrum pins 8 and 9 into 5 and 16. Also,
The design also attracts the attention of the viewer. The connecting portions 23 may be connected by a synthetic resin.

5) In the above embodiment, the scissors 1 are taken as an example. However, the present invention is not limited to scissors as long as they have two blades. For example, FIG. 13 and FIG.
As shown in FIG. Even in this case, by moving the first blade body 22 up and down, the first blade body 22 slides back and forth, and when cutting an object to be cut such as paper with the second blade body 23. Can be cut very smoothly.

In the above embodiment, the elongated hole 10 is formed in the bent portion 1.
The first hole 10a and the second hole 10b have the same length around 0c, but these two holes 10a, 10b
It is also free to vary the length of the. In addition, the present invention can be freely modified and implemented without departing from the gist of the present invention, such as directly erection of the two fulcrum pins 8 and 9 on the second blade body 5.

[0032]

As described in detail above, according to the first aspect of the present invention, it is possible to provide a cutting tool which is easy to design and work, and has a pulling action that does not require any skill in assembly. According to the second aspect of the present invention, in addition to the effect of the first aspect, the cutting can be performed more smoothly and the sharpness is long-lasting.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of scissors according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram illustrating a positional relationship between a fulcrum pin and a long hole in a closed state of the scissors in the first embodiment.

FIG. 3 is an explanatory view illustrating a positional relationship between a fulcrum pin and a long hole in a half-open state of scissors in the first embodiment.

FIG. 4 is an explanatory diagram illustrating a positional relationship between a fulcrum pin and a long hole in a fully opened state of the scissors in the first embodiment.

FIG. 5 is an exploded perspective view of the scissors according to the second embodiment of the present invention.

FIG. 6 is an explanatory diagram illustrating a positional relationship between first and second long holes in a closed state of the scissors according to the second embodiment.

FIG. 7 is an explanatory diagram illustrating a positional relationship between first and second long holes in a half-open state of the scissors of the second embodiment.

FIG. 8 is an explanatory diagram illustrating a positional relationship between first and second long holes in a fully opened state of the scissors of the second embodiment.

FIG. 9 is an explanatory diagram illustrating a moving direction of a blade body in scissors according to a second embodiment.

FIG. 10 is an explanatory view illustrating a positional relationship between a fulcrum pin and a long hole in scissors of another embodiment.

FIG. 11 is a front view of a long hole formed in a blade body of scissors in another embodiment.

FIG. 12 is a perspective view of a fulcrum pin used for scissors according to another embodiment.

FIG. 13 is a side view illustrating a push-off operation according to another embodiment.

FIG. 14 is a side view illustrating a push-off operation according to another embodiment.

FIG. 15 is an explanatory diagram illustrating a rotary portion of a conventional scissors in an enlarged manner.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Scissors which are cutting tools, 2 ... First blade body, 3, 4 ... Cutting blade, 5
... First blade body, 7, 8... Fulcrum pin, 10.
... bent part, 19 ... long hole.

Claims (2)

(57) [Claims] An elongated hole having a bent portion at a center portion is formed in a first blade body provided with a cutting blade, and a pair of fulcrum pins projecting from a second blade body provided with a cutting blade are provided in the bent portion. Is regulated by the distance between the end of the slot and the end of the slot, and it is loosely fitted in the slot to support both blades, and both fulcrum pins are alternated at the bent part in synchronization with the cutting operation of both blades A cutting tool arranged to slide between both ends of the elongated hole and the bent portion. 2. A first blade having a cutting edge, a first elongated hole having a bent portion at a center portion is formed, and a second blade having a cutting edge is provided with a first blade. A second elongate hole of substantially the same size having a bent portion that bends in a direction opposite to the formed long hole is formed, and a pair of fulcrum pins are regulated by the distance between the bent portion and the end of the same long hole. To support the blades by loosely fitting into the slots.
A cutting tool, wherein both fulcrum pins are arranged so as to slide between an end of a long hole and a bent portion at a bent portion in synchronization with a cutting operation of the two blades.