Cutting tool

Abstract

To achieve stable grip holding and handle operation with a simple structure in a cutting tool of a so-called pliers type.SOLUTION: The wire 1, which is a cutting tool of a pincer type, has a cylindrical finger hook portion 50 protruding parallel to the rotation shaft 30 between the grip 11 and the rotation shaft 30 of the upper handle 10. The thumb is hooked on the finger hook 50, the grip 11 of the upper handle 10 is wrapped with the palm, and the grip 21 of the lower handle 20 is gripped with the fingers other than the thumb among the five fingers, so that the grip can be stably held and the handle can be stably operated. Since there is no need to modify the structure of the wire 1 other than providing the finger hook 50, the wire 1 is simple.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a pliers-type cutting tool. [Background technology]

[0002] BACKGROUND ART So-called pliers-type cutting tools, such as pliers, scissors, and pipe cutters, are known in which a tool is gripped by the grips of a pair of handles connected by a rotating shaft and rotated to cut an object using a cutting mechanism linked to the handles.

[0003] One type of pliers-type cutting tool is a wire stripper, as described in Patent Documents 1 to 3, which cuts only the insulating coating at the end of a wire, leaving the core wire of the wire, and then peels off the insulating coating. In order to achieve this two-step operation of cutting and peeling off the insulating coating simply by gripping the grip and operating the handle, wire strippers employ a relatively complex structure in which the grip and cutting mechanism are connected by a link mechanism.

[0004] Combined with the use of such a complex structure, it is difficult to control the amount of force used when operating the handle, and it is necessary to maintain a stable grip to avoid poor cutting of the insulating coating or leaving any areas unremoved.

[0005] Here, in order to allow smooth operation of the handle, Patent Documents 1 to 3 attempt to change the position and structure of the link mechanism and cutting mechanism, but there are concerns that this may further complicate the structure of the wire stripper and increase manufacturing costs. Furthermore, this type of problem is not limited to wire strippers, but applies to all plier-type cutting tools. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-136073 [Patent Document 2] Japanese Patent Application Laid-Open No. 2006-200374 [Patent Document 3] Japanese Patent Application Laid-Open No. 2008-5577 Summary of the Invention [Problem to be solved by the invention]

[0007] Therefore, an object of the present invention is to provide a so-called pliers-type cutting tool with a simple structure that allows stable gripping and handle operation. [Means for solving the problem]

[0008] In order to solve the above-mentioned problems, the pliers-type cutting tool of the present invention is provided with an additional finger hook adjacent to the grip of the handle.

[0009] More specifically, the cutting tool of the invention comprises a pair of handles each having a grip at its rear end, a rotating shaft that rotatably connects the pair of handles in a crossed state, a cutting mechanism that is arranged at the front end of the pair of handles and operates in conjunction with the rotation of the handles, and a columnar finger hook that is connected between the grip of one of the pair of handles and the rotating shaft and protrudes parallel to the rotating shaft, and is configured so that by placing the thumb on the finger hook and the remaining five fingers on the grip of the other of the pair of handles and rotating the pair of handles, the cutting mechanism cuts the object to be cut. Here, the term "between the grip and the rotation axis" includes the area on the grip and the area on the rotation axis.

[0010] With this configuration, by placing the thumb on the finger rest, it is possible to grip the grip stably, allowing for smooth operation of the handle. Since the finger hook portion is simply added without modifying the conventional mechanism such as the cutting mechanism, the structure of the cutting mechanism does not become complicated.

[0011] In the cutting tool according to the present invention, it is preferable that the finger grip portion has a recess on its outer periphery into which the ball of the thumb can fit. This configuration improves the fit of the thumb to the finger rest, further improving operability.

[0012] In the cutting tool according to the present invention, it is preferable that the finger grip portion has an uneven anti-slip portion on its outer periphery. With this configuration, the thumb hooked on the finger hook portion will not slip, further improving operability and preventing operational errors.

[0013] The cutting tool of the present invention may further include an insertion bracket connected to the tip of the finger grip portion in the protruding direction, and the insertion bracket may be configured to be attachable to and detachable from a portable holder by being inserted into and removed from the holder. With this configuration, when the cutting tool is not in use, it can be held in a portable holder attached to a harness or the like or fastened to a waist belt. Furthermore, when the cutting tool is held in the holder, a gap is formed between the holder and the cutting tool, the length of which corresponds to the length of the finger hook in the protruding direction, making it easy to insert your fingers into this gap to grasp the cutting tool when using it. This also improves the operability when sliding the insertion bracket out of the holder.

[0014] In the cutting tool according to the present invention, the insertion bracket may be disk-shaped and rotatable while held by the holder. With this configuration, the cutting tool can be rotated to a position where it is easy to grip while still being held by the holder, further improving operability.

[0015] The cutting tool of the invention may further include a locking arm between the finger grip portion and one of the handles that is rotatable around an axis whose axis is the direction in which the finger grip portion protrudes, and the other handle has a pin that protrudes parallel to the rotation axis, and by rotating the locking arm, the hook at its tip can be engaged and disengaged with the pin. With this configuration, by locking the cutting tool when not in use, it is possible to prevent the cutting tool from malfunctioning due to unintentional rotation of the handle, etc. The lock arm is positioned close to the base of the finger hook, allowing for a smooth transition from cutting operations to locking operations.

[0016] In the cutting tool of the present invention, the locking arm can be configured to have, at both ends of its longitudinal direction, a first tab on which the thumb can be placed to rotate the locking arm, and a second tab on which one of the remaining five fingers can be placed to rotate the locking arm. With this configuration, locking and unlocking operations can be performed simply by slightly moving the thumb from the position where it is placed on the finger rest to touch the first tab, or by slightly moving the remaining fingers, such as the index finger, from the position where it is gripping the grip to touch the second tab, thereby further improving operability.

[0017] The cutting tool according to the present invention is preferably a wire stripper. With this configuration, the two-stage operation of cutting and peeling off the insulating coating can be smoothly performed by holding the grip and the finger hook portion. [Effects of the Invention]

[0018] The cutting tool according to the present invention is configured as described above, and thus it is possible to achieve stable gripping and handle operation with a simple structure. [Brief explanation of the drawings]

[0019] [Figure 1]Perspective view of wire stripper [Figure 2] A side view showing the wire stripper gripped [Figure 3] A side view showing the state in which the lock arm of the wire stripper is operated [Figure 4] An enlarged view of the main part showing the process of cutting the wire insulation coating with a wire stripper and then peeling and removing it. [Figure 5] A side view showing the wire stripper held in the holder [Figure 6] Perspective view of the pipe cutter [Figure 7] Enlarged side view of the main part of the pipe cutter DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The wire stripper 1 of the embodiment shown in Figures 1 to 5 includes a pair of upper and lower handles 10, 20, a rotating shaft 30 that rotatably connects the pair of upper and lower handles 10, 20 in a crossed state, and a cutting mechanism 40 that operates in conjunction with the rotation of the handles.

[0021] As shown in Figures 1 to 3, a pair of upper and lower handles 10, 20 have grips 11, 21 at their rear ends, respectively, and by grasping the grips 11, 21, they can be rotated around a rotation axis 30 acting as a pin in a closing direction in which the grips 11, 21 move closer to each other, and in an opening direction in which the grips 11, 21 move away from each other. The wire stripper 1 is also equipped with a spring (not shown) that biases the handles 10 and 20 in the opening direction. The cutting mechanism 40 is disposed forward of the rotation axis 30 of the handles 10, 20, and cuts the insulating coating s at the end of the wire w and peels it off to remove it.

[0022] As shown in FIGS. 1 to 3, of the pair of upper and lower handles 10, 20, a lower jaw 41 that forms part of a cutting mechanism 40 is connected to the front end of the upper handle 10 via a bent portion that bends downward. A lower blade 41a for cutting the insulating coating s of the wire w stands up from the upper surface of the lower jaw 41. The lower blade 41a is formed in a concave arc shape so as to cut only the insulating coating s and not the core wire c. Further, guides 41b for holding the wire w on the lower blade 41a are provided on both sides of the lower blade 41a.

[0023] 1 to 3, a head plate 42, an upper jaw plate 43, and a support plate 44, which form part of a cutting mechanism 40, are connected to the front end of the lower handle 20 via a rotation shaft 30. The front ends of the head plate 42, upper jaw plate 43, and support plate 44 are bent at right angles to the front-to-rear direction of the lower handle 20, i.e., in the left-to-right direction, to form a head 42a, an upper jaw 43a, and a support portion 44a. The head 42a, upper jaw 43a, and support portion 44a are arranged in parallel in this order from front to rear.

[0024] As shown in FIGS. 1 to 3, the head 42a faces the lower jaw 41 in the vertical direction, and can move towards or away from the lower jaw 41 in the vertical direction as the handles 10 and 20 are rotated. To realize this vertical rotational movement, a linear elongated hole 42b extending in the front-to-rear direction is formed at the rear end of the head plate 42, and this part is connected to the middle part of the lower handle 20 in the front-to-rear direction by a link mechanism 45. This long hole 42b provides play in the front-rear direction, so that the link mechanism 45 acts only in the direction of pushing up and down the head plate 42, and the operation of the handles 10, 20 in the closing direction causes only rotational movement. The head portion 42a presses the wire w from above to prevent it from shifting when the insulating coating s of the wire w is cut or peeled off and removed.

[0025] The upper jaw 43a also faces the lower jaw 41 in the vertical direction, and can move towards or away from the lower jaw 41 in the vertical direction in accordance with the rotation of the handles 10 and 20. An upper blade 43b for cutting the insulating coating s of the wire w hangs down from the underside of the upper jaw 43a. The upper blade 43b is formed in a concave arc shape so as to cut only the insulating coating s and not the core wire c.

[0026] In order to peel off and remove the cut insulating coating s, the upper jaw 43a is configured so that its upper blade 43b overlaps the lower blade 41a of the lower jaw 41, and then by further closing the handles 10 and 20, the entire upper jaw plate 43 slides back and forth. To allow this sliding, a linear elongated hole (not shown) extending in the front-rear direction is provided in the portion of upper jaw plate 43 that is the middle portion in the front-rear direction where rotation shaft 30 passes through. In addition, the rear end of upper jaw plate 43 and the middle portion in the front-rear direction of lower handle 20 are connected by link mechanism 45. Therefore, when handles 10, 20 are operated in the closing direction, if the rotation of lower handle 20 exceeds a predetermined angle, the action of link mechanism 45 converts the rotational movement of the handle into linear movement, and upper jaw 43a is pulled rearward.

[0027] The support portion 44a is located at a position that is almost in contact with the lower blade 41a of the lower jaw 41, and can slide together with the support plate 44 in the front-rear direction relative to the lower jaw 41 as the handles 10, 20 are rotated, thereby moving towards or away from the lower jaw 41. The support portion 44a sandwiches the cut insulating coating s between the upper jaw 43a and peels it off and removes it.

[0028] To allow this sliding, a linear elongated hole (not shown) extending in the front-to-rear direction is provided in the portion through which the rotation shaft 30 passes, which is the intermediate portion in the front-to-rear direction of the support plate 44. In addition, an arc-shaped elongated hole 44b extending in the up-down direction is provided at the connecting portion between the support plate 44 and the link mechanism 45, which is the rear end of the support plate 44. As described above, the link mechanism 45 is connected to the lower handle 20, but since there is play between the support plate 44 and the link mechanism 45 due to the arc-shaped long hole 44b, even if the handles 10 and 20 are operated in the closing direction, the link mechanism 45 does not initially act and the support plate 44 does not move. Then, when further operation is performed in the closing direction and the rotation of the lower handle 20 exceeds a predetermined angle, the action of the link mechanism 45 converts the rotational movement of the handle into linear movement, and the support part 44a is pulled rearward along the linear elongated hole extending in the front-to-rear direction. Here, the shapes, positions, etc. of the elongated hole extending in the front-to-back direction of the upper jaw plate 43, the linear elongated hole extending in the front-to-back direction of the support plate 44, and the arc-shaped elongated hole 44b extending in the up-down direction are adjusted so that the timing of sliding the upper jaw 43a and the support part 44a backward is synchronized.

[0029] With the above-described structure, as shown in Figure 4(a), when the end of the wire w is positioned between the upper jaw 43a and the lower jaw 41 and the handles 10 and 20 are operated in the closing direction, the concave arc-shaped upper blade 43b and lower blade 41a approach each other, as shown in Figure 4(b), and only the insulating coating s of the wire w is cut, leaving the core wire c. If the handles 10 and 20 are further operated in the closing direction from this state, the cut insulating coating s is sandwiched between the upper jaw 43a and the support part 44a and pulled out rearward, thereby being peeled off and removed, as shown in Figure 4(c). During the series of operations, the head 42a covers the wire w from above, thereby preventing it from slipping. The end of the wire w where the core wire c is exposed is connected to an electrical component or the like.

[0030] 1 to 3, a finger hook 50 is provided between the connection point of the upper handle 10 with the rotary shaft 30 and the grip 11. The finger hook portion 50 is generally cylindrical and protrudes from the side of the upper handle 10 so that its axis is substantially parallel to the axis of the rotation shaft 30. Finger hook 50 has a concavely curved recess 51 formed on the upper outer periphery, and inside recess 51 there are small protrusions scattered like dots to form anti-slip portion 52. Recess 51 is tilted slightly forward as a whole.

[0031] When operating the handles 10, 20, as shown in Figure 2, the thumb is placed on this finger loop 50, the grip 11 of the upper handle 10 is wrapped around the palm of the hand, and the grip 21 of the lower handle 20 is grasped with the fingers other than the thumb, which stabilizes the grip and improves operability. By placing the ball of the thumb in the recess 51 of the finger hook 50, the fit is improved, and the anti-slip portion 52 prevents the thumb from slipping.

[0032] The manner in which the finger hook 50 is connected to the upper handle 10 is not particularly limited, and examples include forming it integrally with the upper handle 10, or forming it separately and then fastening it with screws, adhesive, or a band. In any case, the finger hook 50 is fixed to the upper handle 10 so as not to be rotatable around its axis. The shape of the finger hook 50 is not limited to the cylindrical shape in this example, but may be a prismatic or elliptical cylindrical shape. Also, instead of the recess 51, a convex portion with a convex curved surface or a flat portion may be formed. The anti-slip portion 52 is not limited to being uneven, but may be knurled or matte. The material of the finger hook portion 50 is not particularly limited, but examples thereof include synthetic resin, which fits easily to the finger, and soft synthetic resin, which has elasticity, which fits especially well to the finger.

[0033] As shown in FIGS. 1 to 3, a disk-shaped insertion bracket 60 is provided adjacent to the tip end surface of the finger hook portion 50 in the protruding direction. The center of the disk of the insertion bracket 60 and the axis of the cylinder of the finger hook portion 50 are substantially aligned, and the diameter of the insertion bracket 60 is larger than the diameter of the finger hook portion 50 . There are no particular limitations on how the insertion bracket 60 is connected to the finger hook portion 50, and examples include forming the insertion bracket 60 integrally with the finger hook portion 50, or forming it separately and then fastening it by screws or adhesive. In either case, the insertion bracket 60 is fixed to the finger hook portion 50 so as not to be rotatable around its center. As shown in FIG. 5, the insertion bracket 60 can be inserted into and removed from a holder H attached to a harness or the like or attached to a waist belt by sliding it from the side.

[0034] As shown in Figure 5, the holder H has a storage groove G on its surface, and a slider S that can slide back and forth is provided at a position facing the entrance I of the storage groove G. The slider S is biased by a spring in a direction that narrows the entrance I. When the insertion bracket 60 is slid from the entrance I into the storage groove G, it abuts against the slider S, but when it is further pushed in against the bias of the spring, the slider S slides away in the direction to open the entrance I, and the insertion bracket 60 is inserted into the storage groove G. When the insertion bracket 60 passes through the entrance I and is released from the pushing force, the slider S slides in the direction narrowing the entrance I due to the bias of the spring, and prevents the insertion bracket 60 from coming off. In this way, the wire stripper 1 can be held by the holder H when not in use.

[0035] Since the insertion bracket 60 is disk-shaped, the wire stripper 1 can be rotated while being held by the holder H as shown in FIG. 5(b). This allows the wire stripper 1 to be positioned at an angle that makes it easy to grip with the hand and remove from the holder H, and coupled with the fact that the finger hook portion 50 forms a gap between the cutting tool body and the holder H that makes it easy to insert fingers, this improves operability. The shape of the insertion bracket 60 is not limited to the disk shape of this example, but may also be rectangular. The material of the insertion bracket 60 is not particularly limited, but to prevent wear caused by insertion into and removal from the holder H, it may be made of a metal such as stainless steel, for example.

[0036] As shown in FIGS. 1 to 3, a plate-shaped lock arm 70 is provided at the boundary between the finger hook 50 and the upper handle 10, which corresponds to the base portion of the finger hook 50 with a reduced diameter. The lock arm 70 is rotatable around the axis of the finger hook 50 and has a hook 71 at its tip. Meanwhile, a pin 72 is provided between the grip 21 and the connecting point of the lower handle 20 with the rotary shaft 30. The pin 72 protrudes substantially parallel to the axis of the rotary shaft 30. With the handles 10, 20 operated in the closing direction, the lock arm 70 can be rotated to hook the hook 71 onto the pin 72, thereby locking the handles 10, 20 to prevent them from rotating unintentionally. The rotation range of the lock arm 70 is restricted by a stopper (not shown). The pin 72 also serves as a connecting pin that connects one end of the link mechanism 45 to the lower handle 20. The other end of the link mechanism 45 is bifurcated into left and right parts that sandwich the rear ends of the head plate 42, support plate 44, and upper jaw plate 43 in this order and are connected by pin 45a.

[0037] As shown in FIGS. 1 to 3, a first tab 73 and a second tab 74 are provided at both ends of the lock arm 70 in the longitudinal direction. Therefore, as shown in Figure 3, while gripping the handles 10 and 20, the lock arm 70 can be rotated by hooking the thumb on the first tab 73 or one of the other four fingers, such as the index finger, on the second tab 74, thereby improving operability. The shape of the lock arm 70 is not limited as long as it can lock the handles 10, 20. The material of the lock arm 70 is also not particularly limited, but an example of the material is a metal such as stainless steel, which reduces wear associated with engagement and disengagement with the pin 72.

[0038] As described above, in the wire stripper 1 of the embodiment, the finger hook portion 50, the insertion bracket 60, and the lock arm 70 are all concentrated in approximately the same position. This allows the operations of peeling off the insulating coating s of the wire w, attaching and detaching it to the holder H, and locking and unlocking it to be performed smoothly and continuously without having to significantly change the grip position, dramatically improving convenience.

[0039] The embodiments disclosed herein are illustrative in all respects and are not restrictive. The scope of the present invention is defined by the claims, and all modifications and variations within that scope and in a meaning equivalent to the claims are intended to be included. For example, in the embodiment, the wire stripper 1 is given as an example of a so-called pliers-type cutting tool, but the present invention is applicable to other pliers-type cutting tools in general, such as pipe cutters, pliers, scissors, and the like. In addition, in the case of the wire stripper 1, the configurations of the handles 10, 20, the rotary shaft 30, and the cutting mechanism 40 are not limited to those in the embodiment.

[0040] 6 and 7 show examples of cutting tools according to other inventions related to the present invention. The illustrated example of a cutting tool is a pipe cutter 2. A pair of upper and lower handles 10, 20 have grips 11, 21 at their rear ends, respectively, and by grasping the grips 11, 21, the grips 11, 21 can be operated around the rotation axis 30 in a closing direction in which the grips 11, 21 move toward each other, or in an opening direction in which the grips 11, 21 move away from each other. The upper handle 10 has a concave pipe holder 46 connected to its front end as a cutting mechanism 40, and the lower handle 20 has a blade 47 connected to its front end as a cutting mechanism 40, and when the handle is operated in the closing direction, the pipe p supported by the pipe holder 46 is cut by the blade 47. Unlike the embodiment, the cutting mechanism 40 is connected directly to the handles 10, 20 without the link mechanism 45.

[0041] A disk-shaped insertion bracket 60 is independently connected to the end (rear edge) of the upper handle 10 without the finger hook 50 in between, and similar to the embodiment, it is detachable from the holder H. A cylindrical cover 61 with a bottom is attached to the insertion bracket 60, and the end of the upper handle 10 is inserted into this cover 61 and fixed by appropriate means such as screws. A string hole is provided at the rear end of the cover 61. This allows the string to be threaded through even if the string holes provided on the handles 10, 20 are covered by the cover 61 and become unusable.

[0042] Furthermore, a lock arm 70 is independently connected between the grip 11 of the upper handle 10 and the rotating shaft 30 without the finger hook 50. As in the embodiment, a pin 72 is provided between the grip 21 of the lower handle 20 and the rotating shaft 30, and its hook 71 can be engaged and disengaged by rotating the lock arm 70. A first tab 73 is provided at one longitudinal end of the lock arm 70, and the lock arm 70 can be easily rotated by placing one of the fingers on the first tab 73 while gripping the grips 11, 21. Stoppers 75, which are bent pieces, are arranged in parallel in the middle of the longitudinal direction of the plate-shaped locking arm 70, and the pair of stoppers 75 abut against the edges of the upper handle 10, thereby restricting the rotation range of the locking arm 70. [Explanation of symbols]

[0043] 1 wire stripper 2 Pipe cutter 10 Upper Handle 11 Grip 20 Lower Handle 21 Grip 30 Rotation axis 40 Cutting mechanism 41 Lower jaw 41a Lower blade 41b Guide 42 Head Plate 42a head 42b long hole 43 Upper jaw plate 43a Upper jaw 43b upper blade 44 Support Plate 44a Support part 44b long hole 45 Link mechanism 45a pin 46 Pipe holder 47 blades 50 Finger rest 51 recess 52 Anti-slip part 60 Insertion bracket 61 Cover 70 Lock Arm 71 Hook 72 pins 73 First Tab 74 Second Tab 75 Stopper w Wire s Insulation coating c Core wire H holder G Storage groove I Entrance S slider p pipe

Claims

1. a pair of handles having grips at their rear ends; a rotation shaft that rotatably connects the pair of handles in a crossed state; a cutting mechanism disposed on the front end side of the pair of handles and operating in conjunction with the rotation of the handles; a columnar finger rest that is connected between the grip of one of the pair of handles and the rotation shaft and that protrudes parallel to the rotation shaft; A cutting tool in which the thumb is placed on the finger rest and the remaining five fingers are placed on the grip of the other of the pair of handles, and the pair of handles are rotated to cut the object to be cut using the cutting mechanism.

2. The finger rest further includes an insertion bracket connected to a tip of the finger rest in a protruding direction, The cutting tool according to claim 1 , wherein the insert bracket is detachable from a portable holder by inserting it into the holder and removing it from the holder.

3. a lock arm between the finger hook and the one of the handles, the lock arm being rotatable around an axis that is in the protruding direction of the finger hook; the other handle has a pin that protrudes parallel to the rotation axis, 3. The cutting tool according to claim 1, wherein the lock arm is rotated to allow a hook at a tip end of the lock arm to be engaged with and disengaged from the pin.

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