KR102170148B1 - Wire cutter - Google Patents

Abstract

The present invention provides a lightweight wire cutter capable of cutting metal wires with high hardness, such as hard wires, with light force. The hard wire cutter (1) includes a main body (2) having a fixed blade (4) at its tip, a movable part (12) supported by a main shaft (18) so as to be rotatable with respect to the main body (2), It is provided with an operation part 6 supported by the operation shaft 8 so that rotation with respect to the main body part 2 is possible. The movable part 12 is provided with a movable blade 14 at a position capable of contacting and separating the fixed blade 4. The operation part 6 is provided with a roller 10 serving as an operating point of a lever with the operation shaft 8 as a point. The roller 10 swings by the opening and closing operation of the operation gripping part 6a of the operation part 6 and slides on the pressure receiving part 16 while exerting a pressing force on the movable part 12. A concave portion 16b is formed in the sliding intermediate region of the pressure receiving portion 16 through which the roller 10 slides.

Description

Wire cutter {WIRE CUTTER}

The present invention relates to a hand tools for cutting a wire rod, and in particular, to a wire cutter for cutting a metal wire rod.

As a hand tool for cutting a wire rod, scissors and nippers are widely used. However, in order to cut a wire rod having high hardness such as a metal wire, it is necessary to generate a large force at the time of cutting. Fig. 8 shows a conventional wire rod cutter capable of easily cutting a metal wire by generating a strong force.

The cutter 100 for a wire rod 100 of FIG. 8 includes a handle 101 having a blade portion 103 at a tip end, and a branch piece extending from the handle 101 in a branch shape (支点片, supporting point piece; 108). It is a tool that cuts a wire rod by opening and closing operation with the handle 102 attached to the distal end 108a so as to be rotatable. The handle 102 is connected to a cutter portion 107 having a blade portion 104 through a link piece (105). Then, the link piece 105 is connected to the cutter portion 107 so that the inside of the long hole 107a can be slid.

With this configuration, when the handles 101 and 102 are opened and closed, the blades 103 and 104 are relatively opened and closed with the pin 106 at the tip as an axis. That is, the wire cutter 100 includes a lever mechanism of the cutter portion 107 with the pin 106 as a point, and a lever of the handle 102 centered on the tip 108a. A large force can be generated by a double lever made of a mechanism. For this reason, a thick metal wire such as a mild steel wire can be cut with a light force. A cutter for a wire rod as shown in Fig. 8 is disclosed in Patent Document 1, for example.

Japanese Patent Laid-Open Publication No. 2003-225480

However, according to the conventional cutter 100 for a wire rod, a mild steel wire or the like can be cut with a relatively light force, but since the lever is configured in two stages, it is large and needs to be operated with both hands. Therefore, in cutting a hard wire that requires a larger force, it is necessary to configure a larger tool in order to increase the action of the lever. For this reason, operability is remarkably deteriorated.

In addition, tools such as ratchet cutters, which divide and generate a large force even if small, are known. However, such a ratchet cutter requires a plurality of opening and closing operations each time one wire is cut, resulting in a decrease in work efficiency and an increase in operator fatigue.

Accordingly, an object of the present invention is to provide a wire cutter capable of cutting a metal wire having high hardness such as a hard wire with one hand operation.

In order to achieve the above object, the cutter for a wire rod of the present invention is rotatably supported by a body portion having a fixed blade and a first gripping portion, and a first shaft on the body portion, and the first wave An operation portion having a second gripping portion capable of being opened and closed with respect to the branch portion, and an operating portion having an acting portion operated with a lever around the first axis by opening and closing the second gripping portion, and the body portion is rotated by a second axis A pressure receiving part is installed that is supported by a shaft and has a movable blade at a position capable of contacting and separating the movable blade from the working part, and receiving a pressing force to bring the movable blade close to the fixed blade. It is characterized by comprising a movable portion in which a recess is formed in a sliding intermediate region of the acting portion on the pressure receiving portion.

Further, the cutter for a wire rod of the present invention is characterized in that, in addition to the above configuration, the movable portion is biased with respect to the body portion so that the pressure receiving portion abuts the acting portion.

As described above, according to the present invention, when the second gripping portion is rotated, the acting portion is rotated by the action of the lever, and the pressure receiving portion is in a pressurized state. The movable part is rotated by the pressing force of the acting part, and the movable blade approaches the fixed blade. In the concave portion formed in the intermediate sliding region of the pressure receiving portion, the angle formed by the virtual straight line passing through the first shaft and the acting portion and the pressure receiving portion is maximized. That is, the angle formed by the sliding surface of the circular motion of the acting portion with respect to the rotation direction is smaller than that of other sliding areas. For this reason, in the concave portion, the wedge increasing effect of the acting portion on the pressure receiving portion is maximized, and the movement of the movable portion based on the pressing of the acting portion becomes the smallest. This makes it possible to generate a strong force locally.

In addition, according to the present invention, since the pressure receiving unit is energized so as to abut the acting unit, the pressure receiving unit and the acting unit are in contact with each other in either the opening operation or the closing operation of the second gripping unit. Can deliver.

1 is an overall perspective view of a hard wire cutter according to an embodiment of the present invention.
FIG. 2 is a perspective view showing a state in which the hard wire cutter of FIG. 1 is opened, partially broken.
3 is an enlarged perspective view of a movable part of the hard wire cutter of FIG. 1.
FIG. 4 is a diagram illustrating the operation of the hard wire cutter of FIG. 1, in which (a) is an open state, (b) is a half-open state, and (c) is a fully closed state.
5 is a schematic diagram showing a force relationship acting between a pressure receiving portion and a roller.
6 is an operation explanatory view specifically showing a force relationship acting between the pressure receiving portion and the roller.
7 is a view showing the change in cutting force with respect to the open dimension of the hard wire cutter of FIG.
8 is a view showing a conventional cutter for a wire rod.

A hard wire cutter (cutter for a wire rod) according to an embodiment of the present invention is shown using the drawings.

First, the structure will be described using Figs. 1 to 3, and then the operation will be described using Figs. 4 to 7.

1 is a perspective view showing the entire hard wire cutter 1. The hard wire cutter 1 is largely divided into three parts: a main body 2, a movable part 12, and an operation part 6. In addition, FIG. 2 shows the hard wire cutter 1 in the state where the operation part 6 is open, with the movable part 12 periphery of the main body 2 partially broken. In addition, in FIG. 3, only the movable part 12 is expanded and shown.

Referring to Fig. 1, in the main body 2, a main body gripping part 2a (first gripping part) is provided on one end side, and a fixed blade 4 is sandwiched between opposing plate-shaped members on the other end side. Is fixed. The fixed blade 4 is detachable by fastening bolts, and it is easy to replace even if this occurs.

The operating portion 6 has an operating gripping portion 6a (a second gripping portion), and is pivotably supported by an operating shaft 8 (first shaft) with respect to the body portion 2. Accordingly, the operation gripping portion 6a can be opened and closed with respect to the main body gripping portion 2a. Here, referring to FIG. 2 together, on the side opposite to the operation gripping part 6a with the operation shaft 8 interposed therebetween, a roller 10 exerting a lever action by operation of the operation gripping part 6a is provided. . In the present embodiment, the peripheral portion of the roller 10 serving as a point and an acting point in the lever action is formed in a state that is bent toward the main body 2 side.

The peripheral portion of the roller 10 is formed by opposing plate-shaped members. Then, the main body 2 is sandwiched from the outside by these opposing plate-shaped members, so that the operation part 6 is supported by the main body 2. Further, a curved long hole 2b is formed in the plate-like member of the body portion 2 in which the fixed blade 4 described above is sandwiched. The shaft 10a of the roller 10 is disposed through so as to slide inside the long hole 2b.

As can be seen with reference to FIG. 2, the movable part 12 is formed of a plate-shaped member, and a main shaft 18 (second shaft) so as to be rotatable in an eccentric state on the body part 2 It is supported by Further, the movable blade 14 is provided at a position capable of contacting and separating with the fixed blade 4 in a rotational operation about the main shaft 18. Further, a pressure receiving portion 16 is provided at an end edge of the operation portion 6 facing the roller 10 side to receive a pressing force by a lever action from the roller 10.

Accordingly, when the pressure receiving portion 16 receives a pressing force from the roller 10, the movable portion 12 rotates, and the movable blade 14 approaches the fixed blade 4. Here, referring to FIG. 3, it can be seen that the pressure receiving portion 16 has a recessed portion 16b formed in an intermediate region in which the roller 10 slides. In the present embodiment, the pressure receiving portion 16 is the outer diameter side centered on the main shaft 18 (in Fig. 3, only the axial direction is indicated by substitution with a chain-dotted line). The outer diameter side convex part 16a, the concave part 16b in an intermediate region, and the inner diameter side convex part 16c are formed in the inner diameter side. In Fig. 3, the boundary between these uneven portions is indicated by a dashed-dotted line. Further, a notch 12b is formed between the inner diameter side convex portion 16c of the pressure receiving portion 16 and the main shaft 18.

Returning to Fig. 2, one end of a torsion spring 26 is engaged and fixed to the cutout 12b. The torsion spring 26 is disposed with an operation shaft 8 serving as a rotation center of the operation unit 6 as a spring receiving, and a movable part () in a direction in which the distance between the movable blade 14 and the fixed blade 4 is widened ( 12) is added. In other words, the movable portion 12 is energized so that the pressure receiving portion 16 abuts against the roller 10.

Since it is configured in this way, when the operation gripping part 6a is brought close to the main body gripping part 2a, the roller 10 is pressed against the bias of the torsion spring 26, and the pressure receiving part 16 ) To move toward the main shaft (18). Thereby, the movable blade 14 comes close to the fixed blade 4, and the wire rod can be cut.

Next, the operation of the hard wire cutter 1 will be described with reference to FIGS. 4 to 7.

4 shows three states with respect to the openness of the operation gripping portion 6a. Among these, Fig. 4(a) shows a fully open state, Fig. 4(b) shows a half-open state, and Fig. 4(c) shows a fully closed state.

First, referring to Fig. 4(a), when the operation gripping part 6a is in the deployed state, the roller 10 is of the pressure receiving part 16 of the movable part 12, the outer diameter of the outer diameter near the top part 12a. It is in a state in contact with the side convex portion 16a (see Fig. 3).

In the present embodiment, the diameter of the wire rod having the largest diameter that can be accommodated in the blade base portion as described above is defined as the open dimensions of the movable blade 14 and the fixed blade 4. In Fig. 4(a), since the diameter of the virtual wire rod of the size indicated by the virtual circle 51 is 5.3 mm, the open dimension 52 is 5.3 mm. On the other hand, as an example of an object to be cut, a wire rod 50 having a diameter of 3.2 mm is shown. Accordingly, in the state of Fig. 4(a), since the wire 50 is not sandwiched between the movable blade 14 and the fixed blade 4, the operation gripping portion 6a is cut from the wire rod 50 It can rotate in the closed direction without receiving resistance.

Fig. 4(b) shows a half-open state in which the operation gripping portion 6a is closed to an intermediate position. As can be seen from this figure, some cuts are formed in the wire rod 50 to be cut by the movable blade 14 and the fixed blade 4. In this state, the open dimension 53 is about 2.0 mm. That is, it is a state in which the rotational load of the operation gripping part 6a is raised by receiving the cutting resistance from the wire rod 50.

At this time, the roller 10 in contact with the pressure receiving portion 16 is moving so as to approach the main shaft 18 side from the outer diameter side convex portion 16a on the top portion 12a side of the movable portion 12 (see Fig. 3). . In addition, a state in which the roller 10 on the pressure receiving portion 16 moves to the region of the recessed portion 16b (see FIG. 3) formed at an intermediate position is shown.

Fig. 4(c) shows a state in which the operation gripping part 6a is completely closed, the movable blade 14 and the fixed blade 4 are in contact, and the cutting of the wire 50 is completed. At this time, the roller 10 exits the concave portion 16b formed in the sliding intermediate region on the pressure receiving portion 16 of the movable portion 12, and the inner diameter side convex portion formed on the main shaft 18 side ( 16c, see Fig. 3).

Next, before showing a specific example of the relationship between the force acting between the pressure receiving unit 16 and the roller 10 with respect to the degree of opening of the operating gripping unit 6a, the pressure receiving unit 16 and the roller The relationship of (10) is schematically shown in Fig. 5 and described. In addition, for the surrounding configuration, reference is also made to FIG. 2 described above. In FIG. 5, a dashed-dotted line 30 represents a radial vector direction connecting the main shaft 18 and the contact point of the pressure receiving portion 16 and the roller 10. In addition, the dashed-dotted line 31 is orthogonal to the dashed-dotted line 30 and indicates the rotation direction of the movable part 12.

5 shows an enlarged view of a portion where the roller 10 abuts against the pressure receiving portion 16. The roller 10 performs an arc motion around the operation shaft 8, but it can be considered by replacing it with a wedge that performs a linear motion in an approximate manner.

Thus, as shown in Fig. 5, the roller 10 operated by the operation gripping portion 6a is represented as a wedge 28, and the lever rotational force 22 acting in the arc direction of the roller 10 is represented by the wedge. We think as the driving force of (28).

Then, by the action of the wedge 28 based on the lever rotational force 22, a vertical drag force 20 acts on the pressure receiving portion 16 from the abutting surface of the wedge 28. By the way, since the movable part 12 is axially supported by the main shaft 18, it can move only in the direction of the dashed-dotted line 31 indicating the rotation direction. Accordingly, the movable part 12 receives the force of the cam rotational force 24 which is a component of the vertical drag force 20 in the direction of the dashed-dotted line 31. As described above, as the angle formed by the arc motion direction of the roller 10 with respect to the abutting surface between the pressure receiving portion 16 and the roller 10 is smaller, the increase effect by the wedge 28 becomes remarkable.

Next, as a specific example of FIG. 5, a force relationship acting between the roller 10 and the pressure receiving portion 16 will be described with reference to FIG. 6 corresponding to the three states shown in FIG. 4. 6 shows the configuration of the abutting portion between the roller 10 and the movable part 12, FIG. 6(a) is a force relationship in an deployed state, FIG. 6(b) is a force relationship in a half-open state, and FIG. 6(c) Represents the power relationship in a completely closed state. In addition, for the convenience of explanation, in FIG. 6, configurations of the body portion 2 covering the movable portion 12 and the operation portion 6 other than the roller 10 are omitted, and the movable portion 12 and the roller 10 The positional relationship is schematically shown so that the outline of

From the state of FIG. 6(a) to the state of FIG. 6(c), a state in which the roller 10 slides from the outer diameter side to the inner diameter side on the pressure receiving portion 16 is shown. In addition, in Figures 6 (a) to (c), the lever rotational force 22 acting on the roller 10 is shown in a constant size.

First, referring to Fig. 6(a), in the fully open state, the roller 10 abuts against the outer diameter side convex portion 16a (refer to Fig. 3) near the top portion 12a of the movable portion 12. have. At this time, the direction of the vertical drag force 20 generated with respect to the lever rotational force 22 of the roller 10 is largely inclined toward the main shaft 18. For this reason, the cam rotational force 24 of the rotational direction component of the movable part 12 (dashed-dotted line 31 direction component) is small. However, since the distance between the contact point and the main shaft 18 is the longest, sufficient torque can be obtained even if a large wedge effect is not obtained.

Next, referring to Fig. 6(b), in the half-open state, the roller 10 is in the boundary region from the outer diameter side convex portion 16a to the concave portion 16b (refer to Fig. 3). It abuts against the pressure receiving part (16). At this time, the direction of the vertical drag 20 is acting in a direction close to the rotational direction of the movable part 12, unlike the state of FIG. 6(a). For this reason, as described with reference to FIG. 5, the wedge increasing effect can be obtained, and the magnitude of the cam rotational force 24 in the direction component of the dashed-dotted line 31 is rapidly increased. Further, since the distance to the main shaft 18 is sufficient, a strong torque can be obtained, and cutting becomes easy.

Next, with reference to FIG. 6(c), in the fully closed state, the roller 10 has shown the state which moved from the concave part 16b to the inner diameter side convex part 16c. At this time, the direction of the vertical drag force 20 is inclined largely toward the main shaft 18 as in FIG. 6(a). However, in the abutting position of the roller 10, unlike the case of FIG. 6(a), the angle between the direction of the lever rotation force 22 and the pressure receiving part 16 is not large. For this reason, the wedge increasing effect can be obtained, and the magnitude of the vertical drag force 20 is much larger than that of Fig. 6(a). Accordingly, since the decrease in torque as the abutting position approaches the main shaft 18 is sufficiently compensated, the cutting action of the end plate is maintained, and the work can be reliably completed.

Next, with respect to the operation of the hard wire cutter by a constant gripping force, the relationship of the cutting force to the opening dimension is shown in the graph of FIG. 7. In addition, the graph of Fig. 7 shows a characteristic tendency due to the configuration in which the recess is formed in the sliding intermediate region of the pressure receiving unit, like the hard wire cutter 1 according to the present embodiment, and the hard wire shown in Figs. It is not a characteristic of the wire cutter 1 itself.

Referring to Fig. 7, when the graph is sequentially followed from the larger opening dimension, the cutting force gradually increases as the opening dimension becomes narrower from the larger one. And, the cutting force rapidly increases from a certain opening dimension. In addition, when the opening dimension is narrowed, the cutting force decreases rapidly.

As described above, according to the hard wire cutter according to the present embodiment, a strong force can be generated in the intermediate state of the open dimension, and the cutting force is suppressed to be small in the initial stage and the end stage of cutting.

Since it has such characteristics, it is suitable for cutting hard wires with high hardness, among metal wires.

That is, in general, a metal wire having a high hardness has very low malleability, and thus has a property that is vulnerable to large deformation. Therefore, when the amount of cuts becomes large, it collapses at some place, and the cutting is completed with sudden fracture. In other words, when cutting the hard wire, it is not necessary to generate a cutting force to cover all the area of the diameter of the wire, and it is configured to generate a strong force in the step from the start of cutting to the occurrence of collapse. It is desirable.

In the hard wire cutter 1 in this embodiment described above, this point is considered. Specifically, in the initial stage, the roller 10 is designed so that the abutting surface of the roller 10 with respect to the pressure receiving portion 16 becomes small, and the speed of rotation of the movable portion 12 is increased. Accordingly, in a region that does not contribute to cutting until the movable blade 14 or the fixed blade 4 reaches the wire rod, it can be rotated largely with a small force, so that work efficiency is improved.

And, in the step in which the movable blade 14 and the fixed blade 4 contact the wire rod, it is necessary to transmit the cutting force to the wire rod at one time. For this reason, the abutting angle of the roller 10 with respect to the pressure receiving part 16 is designed so that it may change to an angle at which the wedge effect can be maximized.

Subsequently, in the cutting completion step, as described above, since the metal wire on which the cutting has proceeded is weak and does not require a large force, the cutting force is suppressed in order to mitigate the reaction. Accordingly, scattering of the cut pieces can be prevented, and the work can be performed safely.

As described above, according to the hard wire cutter according to the present embodiment, a strong cutting force is locally generated at the rotational position required for cutting the wire rod, and in the initial operation region that does not contribute to cutting, the movable part is rotated. By increasing the speed, it becomes possible to improve work efficiency. In addition, since the area where the wedge effect is obtained is designed according to the area requiring the most cutting force, cutting can be efficiently performed only with one gripping operation. Like a ratchet cutter or the like, a strong force can be generated, but compared to a tool that needs to perform a plurality of opening and closing operations, the working time is significantly shortened.

Thus, according to the conventional hard wire cutter, even a φ 3.2 mm hard wire, etc., which had to be performed with both hands, can be easily cut with one hand operation.

In addition, in the above-described embodiment, as an example, the operating portion exerting a lever action by the operation portion 6 slides on the pressure receiving portion 16 of the movable portion 12 from the outer diameter side toward the inner diameter side. However, the present invention is not limited to this and may be configured to slide from the inner diameter side to the outer diameter side. For example, in the operation part, by arranging the acting part between the point and the force point, if the acting part slides from the inner diameter side toward the outer diameter side, and the pressure receiving part is formed in the direction in which the increasing effect of the wedge is obtained, the same You can get the effect.

Further, in the above embodiment, a configuration in which the pressure receiving portion 16 is formed of an outer diameter side convex portion 16a, a concave portion 16b of the sliding intermediate region, and an inner diameter side convex portion 16c is shown as an example. At least, it is sufficient that the recess is formed in the sliding intermediate region. That is, if the pressure receiving part is configured so that the tangent line at the point on the pressure receiving part where the roller abuts and the tangent line of the circular arc track of the roller is the smallest in the sliding intermediate area, the wedge is A thickening effect is obtained, and it becomes possible to cut easily.

In addition, in the above embodiment, the configuration in which the roller 10 is installed as an acting part exerting a pressing force on the pressure receiving part 16 is shown as an example, but the concave part 16b of the pressure receiving part 16 can be slid. If possible, for example, a configuration such as a sliding pin may be used.

(Industrial availability)

Since the cutter for wire rods of the present invention can generate a strong cutting force due to the wedge increasing effect only in the rotational region required for cutting, the operating efficiency is improved and the wire rod can be cut with light force. For this reason, it is useful as a hard wire cutter for cutting metal wires with high hardness, such as hard wires and piano wires.

One; Hard wire cutter (cutter for wire rod)
2; Body part
2a; Main body gripping part (first gripping part)
2b; Long gong
4; Fixed blade
6; Control panel
6a; Operation gripping part (second gripping part)
8; Operation axis (1st axis)
10; Roller (acting part)
12; Moving part
12a; Top
12b; Notch (切缺)
14; Operation blade
16; Pressure receiving part
16a; Outer diameter side convex
16b; Concave
16c; Inner diameter side convex
18; Main axis (2nd axis)
20; Vertical drag
22; Lever torque
24; Cam torque

Claims (2)

A body portion having a fixed blade and a first gripping portion,
It has a second gripping part that is pivotably supported by a first shaft with respect to the main body and is openable and closed with respect to the first gripping part, and at the same time, the first shaft is centered by opening and closing the second gripping part. An operation part having an acting part that is operated by a lever,
It is pivotably supported by a second shaft with respect to the main body, and has a movable blade at a position capable of contacting and separating with the fixed blade, and according to the rotation of the second gripping part in the closing direction, the second A pressure receiving unit receiving a pressing force to bring the movable blade close to the fixed blade is installed from the acting unit capable of rotating and sliding toward the inner diameter of the axis, and on the pressure receiving unit, the second axis A cutter for a wire rod, comprising: a movable portion having a concave portion formed in a sliding intermediate region of the acting portion that slides from the convex portion formed on the outer diameter side to the convex portion formed on the inner diameter side in the radial direction. The method of claim 1,
A cutter for a wire rod, characterized in that the movable portion is biased with respect to the body portion so that the pressure receiving portion abuts the acting portion.

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