JP2023172114A - Hand-held blade polishing tool - Google Patents

Abstract

To provide a hand-held blade polishing tool easy to maintain a cutting edge angle that is an angle of a grinding wheel face to a blade face during a polishing work at an ideal cutting edge angle.SOLUTION: A hand-held blade polishing tool X, which can polish a blade of a polishing object as a grindstone 1 provided at a tip part keeps contact with a cutting edge of the blade, comprises a grip part 2 that is a portion gripped by a worker during a polishing work, and a grindstone base part 3 provided on the tip part side than the grip part 2 and provided with the grindstone 1 on a grindstone fixing face 3a directing to the tip during the polishing work. The grindstone base part 3 is formed in a shape having an inclination of 5° to 25° on the grindstone fixing face 3a side with respect to the center axis 2L of the grip part 2.SELECTED DRAWING: Figure 3

Description

Application for application of Article 30, Paragraph 2 of the Patent Act 1. Announcing the prototype product via telecommunications line (Posting date: August 2, 2021, Posting address: https://www.youtube.com/watch?v=vTuBUgIkWjI) 2. We delivered a free prototype product and its flyer to the Kyoto Prefectural Landscape Gardening Cooperative Association (publisher of the flyer: Sanwa Gabori Kogyo Co., Ltd., Kyoto Prefecture Landscape Gardening Cooperative Association), and distributed it to members and other related parties through the association (delivery and Distribution date: August 6, 2021) 3. Announcement of the product version via telecommunications line (Posting date: December 10, 2021, Posting address: https://www.youtube.com/watch?v=CV32PQCHbjk)) 4. Distribution of flyers for the product version (Publisher: Sanwa Abori Kogyo Co., Ltd., Kyoto Prefecture Landscape Gardening Cooperative, Publication date: December 20, 2021) 5. The product was released at the Kyoto Prefecture Landscape Architecture Cooperative Office (Delivery date: February 18, 2020) 6. Introducing the product and distributing a flyer (publisher of the flyer: Sanwa Abori Kogyo Co., Ltd.) to the Japan Landscape Association Federation (March 25, 2020) 7. Products were displayed and sold at the "FY2020 Brokerage Exhibition and Sale" held at the Kyoto Prefecture General Exhibition Center (commonly known as "Kyoto Pulse Plaza"), and a flyer (publisher of the flyer: Sanwa Abori Kogyo) was held. Co., Ltd., Kyoto Prefecture Landscape Architecture Cooperative) (April 24, 2020) 8. At the general meeting of the Japan Federation of Landscape Gardening Associations, we exhibited and sold our products and distributed flyers (publisher of the flyer: Sanwa Gabori Kogyo Co., Ltd., Kyoto Prefecture Landscape Gardening Cooperative Association) (May 19, 2020)

The present invention relates to a hand-held blade sharpener, which is a hand tool equipped with a whetstone for sharpening the blades of landscaping tools, for example.

A hand-held file (commonly known as a diamond file) is known in which fine diamond particles are attached to the surface of the file body as an abrasive material. The following patent document discloses that both the front and back surfaces of the file body, which has a flat overall shape, are formed into arcuate protruding surfaces, sharply pointed edges are formed on both left and right edges, and furthermore, the tip of the file body is formed with sharp edges. , discloses a hand-held file in which the convex surfaces on both the front and back sides are formed flat, sharply pointed edges are formed on both left and right edges, and diamond particles are attached to the entire surface exposed to the outside of the file body. has been done.

With a hand-held file like this, if the surface to be polished is a concave arc surface or flat surface, it can be polished with the convex arc surface or flat surface of the file body in contact with the surface to be polished. In addition, when the part to be polished is a deep part, the edge can be polished with the edge in contact with the surface to be polished, making it possible to perform a variety of polishing operations.

Utility model registration No. 4583274

However, with conventional hand-held files whose overall shape is a straight line, there is a problem in that the angle of the cutting edge (the angle of the grindstone surface relative to the blade) is difficult to stabilize during polishing operations.

The main object of the present invention is to provide a hand-held blade sharpener that can easily maintain the ideal cutting edge angle in order to solve such problems.

In other words, the hand-held blade sharpening tool according to the present invention is a blade sharpening tool that can be sharpened with the whetstone provided at the tip in contact with the cutting edge of the cutter to be polished, and is held by an operator during polishing work. A whetstone base part that is equipped with a handle part and a whetstone base part that extends from the handle part at a predetermined angle toward the tip side, and the face that faces the blade during polishing work is set as the whetstone fixing face. is inclined at an angle of 5 to 25 degrees toward the grindstone fixing surface with respect to the central axis of the handle.

After extensive research, the inventor of the present invention discovered that when performing polishing work using a well-known hand-held blade sharpener whose overall shape is approximately linear (shape in which the central axis of the hand-held part and the whetstone surface are parallel), the The following points were identified as the reasons for the difficulty in stabilizing the angle (the angle at which the whetstone surface touches the cutting edge of the cutter). In other words, if the overall shape of the blade sharpener is approximately straight, when an operator grips the handle and applies operating force in a direction perpendicular to the central axis of the handle, the force will be applied to the whetstone. The force acts only in the direction perpendicular to the surface (see Figure 14(b)), and as a result, the angle of the cutting edge (the angle at which the whetstone surface hits the cutting edge of the cutter) becomes stable during polishing work. This is difficult, and requires polishing work that involves constantly moving the whetstone surface back and forth while being aware of the angle of the whetstone (grindstone surface) relative to the cutting edge.

Therefore, the inventor of the present invention has developed a grindstone base part that extends from the handle part and extends at a predetermined angle toward the tip side, and is inclined at an angle of 5 degrees to 25 degrees toward the grindstone fixing surface with respect to the central axis of the handle part. It has been found that the above problem can be solved by setting the shape to a certain shape. In other words, by setting the whetstone base in a shape that is inclined 5 to 25 degrees toward the whetstone fixing surface with respect to the central axis of the handle, the whetstone face (polishing surface) of the whetstone relative to the central axis of the handle ) has an inclination angle of 5 degrees to 25 degrees, and with such a hand-held blade sharpening tool, when the operator holds the hand part and performs polishing work, the angle of inclination of the hand part is 5 degrees to 25 degrees. When an operating force is applied to the grinding wheel, a force acting in a direction perpendicular to the grinding wheel surface and a force acting in a direction parallel to the grinding wheel surface act as component forces (see FIG. 14(a)). As a result, when you press the grinding wheel surface against the cutting edge while holding the handle and apply a pushing force, a force that causes the grinding wheel surface to slip (a force acting in a direction parallel to the grinding wheel surface) occurs even if you are not consciously aware of it. The angle of the cutting edge is stable without having to be particularly conscious of the angle of the surface. If the sharpening tool has an angle of inclination of the whetstone base toward the whetstone fixing surface side relative to the central axis of the handle, which is set to less than 5 degrees, then place the whetstone surface against the cutting edge while gripping the handle. When a pushing operation force is applied, the "force for the grinding wheel surface to slide (force acting in a direction parallel to the grinding wheel surface)" is small, and almost the same phenomenon occurs as in the case of the blade sharpener whose overall shape is approximately straight as described above. Cheap. In addition, if the angle of inclination of the whetstone base toward the whetstone fixing surface side with respect to the central axis of the handle exceeds 25 degrees, the component of the operating force applied during polishing should be applied in a direction parallel to the whetstone surface. The applied force (the force that causes the grindstone to slide) increases, causing unintended movements for the operator when sharpening the blade edge, giving the operator a sense of discomfort. In addition, if the angle of inclination of the whetstone base toward the whetstone fixing surface with respect to the central axis of the handle exceeds 25 degrees, the whetstone will naturally move along the whetstone surface in the direction of pushing the whetstone. Verification has revealed that when returning it, a force is applied in the opposite direction to the returning direction, causing trouble in the work.

In the present invention, as the grindstone base part, one in which the thickness is set gradually smaller toward the tip is applied, or one in which the thickness dimensions of both side parts of the grindstone base part are set gradually smaller towards the side edges is applied. This makes it possible to reduce the thickness of the tip of the blade sharpener, allowing access to the area near the base, where the blades of scissors intersect (connection area), for example, and to perform appropriate sharpening work. be able to.

Regarding the grindstone in the present invention, there are no particular limitations on the material or composition, but a diamond-oriented grindstone is preferred, as it has superior grinding power and has a longer lifespan than general grindstones.

According to the present invention, the angle of inclination of the whetstone base toward the whetstone surface with respect to the central axis of the handle is set within the range of 5 degrees to 25 degrees, thereby stabilizing the angle of the whetstone with respect to the blade during polishing work. It is possible to provide a hand-held blade sharpening tool that is easy to obtain and can obtain a cutting edge angle close to the ideal.

1 is an overall perspective view of a hand-held blade sharpener according to an embodiment of the present invention. FIG. 2 is a perspective view of the hand-held blade sharpener according to the same embodiment, viewed from a direction different from that in FIG. 1 . FIG. 3 is a side view of the hand-held blade sharpener according to the embodiment. FIG. 3 is a plan view of the hand-held blade sharpener according to the embodiment. FIG. 3 is a bottom view of the hand-held blade sharpener according to the embodiment. FIG. 3 is a front view of the hand-held blade sharpener according to the embodiment. FIG. 3 is a rear view of the hand-held blade sharpener according to the same embodiment. FIG. 3 is a diagram showing an actual hand-held blade sharpener according to the embodiment. FIG. 3 is a diagram showing how to hold the hand-held blade sharpener according to the embodiment. FIG. 3 is a diagram showing how to hold the hand-held blade sharpener according to the embodiment. FIG. 3 is a diagram showing how to hold the hand-held blade sharpener according to the embodiment. The figure which shows the state where the hand-held blade sharpener based on the same embodiment is applied to the blade of pruning shears. The work of sharpening the blade of pruning shears using the hand-held blade sharpener according to the embodiment. FIG. 4 is an explanatory diagram regarding the operating force applied when using the hand-held blade sharpener according to the embodiment.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

As shown in FIGS. 1 to 7, the hand-held knife sharpener X according to this embodiment includes a grindstone 1 provided at the tip, a handle part 2 (grip part) having a roughly cylindrical shape, and a handle part 2 (grip part). 2 and a generally plate-shaped grindstone base portion 3 extending at a predetermined angle toward the distal end side. Here, FIG. 1 is an overall perspective view of the hand-held knife sharpener X, and FIG. 2 is an overall perspective view seen from a different angle from FIG. 3 to 7 are a side view, a top view, a bottom view, a front view, and a rear view of the hand-held knife sharpener X, respectively.

The handle part 2 has a size that allows a polishing operator to grasp it with the whole of one hand, and has four finger-holding depressions (recesses 21) formed at a predetermined pitch in the longitudinal direction (axial direction D1). (See Figures 2, 3, 5, etc.). In this embodiment, the surface of the handle portion 2, which is approximately cylindrical in shape with a diameter of 22 mm, on which the recess 21 is formed is the downward surface 2a, and the surface opposite to the downward surface 2a is the upward surface 2b. The thickness direction (vertical direction) D2 of the hand-held knife sharpener X (furthermore, the entire hand-held knife sharpener It is defined as the width direction D3. A flat sloped surface 22 that slopes diagonally forward is formed at the tip of the upward surface 2b of the handle portion 2 (the boundary portion with the grindstone base portion 3), and the operator should place his or her fingers (for example, the Polishing work can be done with one finger (thumb) or second finger (index finger). In the present embodiment, through holes 23 penetrating in the width direction D3 are formed at predetermined portions on the proximal end side and the distal end side of the handle portion 2, respectively, so that a string or the like can be passed through the through holes 23 as appropriate. (See Figure 3, etc.). This through hole 23 also contributes to reducing the weight of the handle portion 2.

The whetstone base portion 3 has a generally plate-like shape with an outward facing surface 3b (upward facing surface) being an inclined surface that is continuous with the finger resting inclined surface 22 of the handle portion 2, and is opposed to the outward facing surface 3b in the thickness direction D2. A grindstone 1 is fixed to an inward facing surface 3a (downward facing surface). That is, the inward surface 3a of the whetstone base portion 3 that faces the cutter that is the object to be polished during polishing work is set as the whetstone fixing surface 3a, and the whetstone 1 is irremovably fixed to the whetstone fixing surface 3a. A smooth concave curved surface 4 is provided in a portion extending from the downward facing surface 2a at the tip of the handle portion 2 to the base end of the inward facing surface 3a of the whetstone base portion 3 (the boundary portion between the handle portion 2 and the whetstone base portion 3). (See Figures 2, 3, etc.). The width dimension of the whetstone base part 3 is smaller than the diameter of the handle part 2 (22 mm in this embodiment), and is set to become smaller gradually toward the tip (see FIG. 4). In this embodiment, the whetstone base part 3 is placed at an angle of 10 degrees (the angle indicated by the symbol θ1 in FIG. 3) with respect to the central axis 2L of the handle part 2 on the whetstone fixing surface 3a side (the whetstone 1 side). ). Further, the tip of the outward facing surface 3b of the whetstone base portion 3 is chamfered so that the thickness gradually decreases toward the tip, and both side portions of the whetstone base portion 3 are also chamfered. , the thickness is set so that it gradually decreases from the center toward the side edge (side) in the width direction D3. In this embodiment, the overall thickness of the grinding wheel base portion 3 is set to 5 mm, and the chamfered tip portion is set to a thickness of 1 mm/an angle of 9 degrees. On the other hand, the whetstone fixing surface 3a, which is the inward facing surface of the whetstone base portion 3, is a surface parallel to the extending direction of the whetstone base portion 3, and is inclined at an angle of 10 degrees with respect to the central axis 2L of the handle portion 2. It is a flat surface.

The whetstone 1 is constructed using a diamond whetstone. More specifically, it is a resinoid diamond grindstone manufactured using fine artificial diamond abrasive grains and resinoid resin. In this embodiment, a flat resinoid diamond grindstone with a thickness of 3 mm and a total length of 50 mm is used. In the knife sharpener X according to the present embodiment, a roughly oval-shaped grindstone 1 whose width is set to gradually decrease toward the tip is fixed to a grindstone fixing surface 3a of a grindstone base part 3 by adhesive. The whetstone surface 11, which is the surface for sharpening the cutting edge of the whetstone 1, is a plane parallel to the whetstone fixing surface 3a of the whetstone base part 3, and is a flat face inclined by 10 degrees with respect to the central axis 2L of the handle part 2. Yes (see Figure 3). In this embodiment, the planar dimensions of the grindstone 1 are set to be larger than the planar dimensions of the grindstone fixing surface 3a of the grindstone base portion 3 by a predetermined amount, and when viewed from the outward surface 3b side (above) of the grindstone base portion 3 In this case, both side portions and the tip portion of the whetstone 1 are set to be exposed without being covered by the whetstone base portion 3 (see FIGS. 1, 4, etc.). Therefore, the operator can easily grasp and specify the position of the grindstone 1 from above the grindstone base portion 3 (above the hand-held knife sharpener X).

In this embodiment, the handle part 2 and the whetstone base part 3 are integrally made of aluminum, and the overall length (total length) of the hand-held knife sharpener X in which the whetstone 1 is fixed to the whetstone base part 3 inseparably is 170 mm. (See Figure 8). When the part consisting of the handle part 2 and the whetstone base part 3 is considered as a holder H, the hand-held knife sharpener X of this embodiment forms the handle part 2 in the base end side region of the holder H, A whetstone base portion 3 is formed in a region on the tip side of the holder H, and a whetstone 1 is provided on the whetstone base portion 3. In this embodiment, the total length of the handle portion 2 is set to approximately 120 mm (see FIG. 8). Therefore, about 70% of the entire length of the holder H from the proximal end to the distal end is set as the handle portion 2.

As shown in FIGS. 9 and 10, the hand-held knife sharpening tool The polishing work can be carried out by holding the tool by placing it on the surface 22 and hooking the remaining fingers into the finger hook recess 21 of the handle section 2. Incidentally, the polishing work can be carried out even if the handle portion 2 is held without placing the finger on the finger-holding inclined surface 22 (see FIG. 11) or in a holding manner in which the finger-holding concave portion 21 is not placed on the finger-holding concave portion 21. In this way, by setting the entire length of the handle part 2 to a length that can be held by all fingers, it is possible to use a hand-held knife sharpener whose length is set so that only the pinky finger cannot be hung on the handle part 2. In comparison, it is easier to apply force during polishing work, the hands are less likely to get tired, and time-consuming polishing work can be performed in a stable state. In the verification conducted by the present inventor, in the case of an adult male with a height of 170 cm, the length of the handle part 2 (the length from the base end of the hand-held knife sharpener X to the part where the grindstone 1 is installed) is 95 mm or less. It was found that the polishing work could not be performed stably because the user could not place his or her little finger on it.

In the tip portion (head portion) of the hand-held knife sharpener X of this embodiment, the tip portions of the 3 mm thick grindstone 1 and the grindstone base portion 3 with a thickness of 1 mm and an angle of 9 degrees overlap. Therefore, the hand-held knife sharpener X according to the present embodiment includes a head portion with a minimum thickness of 4 mm, and is capable of polishing the blade of an object to be polished with the grindstone 1 of the head portion.

To carry out the polishing work, first, the operator holds the hand-held knife sharpening tool A grinding wheel 1 is applied to the cutting edge of a cutter to be polished. When polishing general pruning shears S as shown in FIG. 12, the object to be polished is the cutting edge S11 of the cutting edge S1. Conventional hand-held files have a thick tip (head part) where the whetstone is installed, so when you try to apply the whetstone to the cutting edge S11 of the cutting edge S1, the head part interferes with the receiving blade S2 of the pruning shears S. In many cases, the blade could not be sharpened at an ideal edge angle unless the connection between the two blades S1 and S2 at the cross-connection SC was released (disassembled).

On the other hand, in the hand-held knife sharpening tool X according to the present embodiment, as described above, the thickness of the head portion is set to 3 mm of the thickness of the whetstone 1, and the thickness of the tip of the whetstone base portion 3 is 1 mm/angle of 9 degrees is added. As shown in Fig. 13, even if the pruning shears S has two blades S1 and S2 connected at the cross-connection part SC, it will not interfere with the receiving blade S2. The tip (grindstone 1) of the hand-held knife sharpener X can be brought into contact with the cutting edge S11 of the cutting edge S1 without having to do so. Note that FIG. 13(a) is a view from above when the tip (grindstone 1) of the hand-held knife sharpener X is applied to the cutting edge S11 of the cutting edge S1, and FIG. , is a cross-sectional view taken along the line AA, which coincides with the central axis 2L of FIG. In the hand-held knife sharpener X according to the present embodiment, the inclination angle θ1 of the grindstone base portion 3 toward the grindstone fixing surface 3a side (the grindstone 1 side) with respect to the central axis 2L of the handle portion 2 is set to 10 degrees. By doing so, as shown in FIG. 13(b), the polishing work can be performed while maintaining the cutting edge angle θ2 at about 25 degrees without the operator being particularly conscious of it. Here, the cutting edge angle θ2 can be defined by the inclination angle of the grindstone surface 11 with respect to the surface S12 of the cutting edge S1, as shown in FIG. 13(b). That is, according to the hand-held knife sharpener X according to the present embodiment, the grindstone base portion 3 is placed on the grindstone 1 side (in the direction approaching the center axis 2L of the handle portion 2) with respect to the center axis 2L of the handle portion 2. The grinding wheel surface 11 is tilted by 10 degrees at an inclination angle θ1 with respect to the central axis 2L of the handle part 2 (when the central axis 2L of the handle part 2 is used as a reference line, it is tilted in a direction away from the reference line). By setting the angle of inclination of the whetstone surface 11 to be 10 degrees, when the whetstone surface 11 is applied to the cutting edge S11 of the cutting edge S1 in a sharpening posture, the cutting edge angle θ2 (blade angle θ2) will naturally change. The cutting edge angle θ2 (blade edge angle θ2) is approximately 25 degrees, and the operator can perform the polishing work smoothly and accurately with the cutting edge angle θ2 (blade edge angle θ2) close to the ideal.

Specifically, by inclining the whetstone base part 3 by 10 degrees toward the whetstone fixing surface 3a with respect to the central axis 2L of the handle part 2, as shown in FIG. 14(a), the handle part 2 When an operator applies a pushing force in a direction perpendicular to the central axis 2L of the wheel, a force acting in a direction perpendicular to the grinding wheel surface 11 as a component force and a direction parallel to the grinding wheel surface 11. A force acts on the Therefore, when an operator performs polishing work while gripping the handle part 2 with a certain force, if a pushing force is applied in a direction perpendicular to the central axis 2L of the handle part 2, the grinding wheel surface will naturally shift. 11 (force acting in a direction parallel to the grinding wheel surface 11) acts, and the angle of the grinding wheel surface 11 relative to the cutting edge S11 is stabilized without having to be particularly conscious of the angle of the grinding wheel surface 11, and the cutting edge During the polishing operation (sharpening operation) in which the whetstone surface 11 is reciprocated while lightly touching the blade in S11, deviation (an event in which the blade edge angle deviates significantly from a good one) is unlikely to occur.

Furthermore, according to the hand-held knife sharpening tool X according to the present embodiment, as shown in FIG. An ideal cutting edge angle θ2 that allows the polishing work to be carried out suitably can be obtained even in the case of In particular, according to the hand-held knife sharpener X according to the present embodiment, as shown in the figure, when polishing approximately 2/3 of the position from the tip of the blade, when the blade edge angle θ2 is 25 degrees, For a total length of the grindstone 1 of 50 mm (length 1L in the figure), it is possible to secure a stroke (length 1T in the figure) up to 33 mm (2/3 of the total length) from the tip of the grindstone 1. As shown in FIG. 13(a), the distance between the cutting edge S1 and the receiving blade S2 (sickle blade) increases toward the tip, so when sharpening the cutting edge S1, approximately 2/2 The parts up to 3 can be sharpened with the necessary and sufficient effective stroke length 1T of the grindstone 1.

As described above, the hand-held knife sharpener X according to the embodiment includes a dedicated grindstone 1 containing micron-sized fine artificial diamonds, which has excellent grinding power and a long life compared to general grindstones. It is a handy type sharpening tool that uses a lightweight and compact aluminum grip (handle part 2), which fits comfortably in the hand, is easy to hold, and can be sharpened with water in the same way as a general whetstone 1. In the hand-held knife sharpener X according to the embodiment, the tip portion where the diamond grindstone 1 is provided is inclined at an angle of 10 degrees with respect to the central axis 2L of the handle portion 2. Therefore, as shown in FIG. 14(a), when an operator grips the holder H and applies an operating force in a direction perpendicular to the central axis 2L of the handle 2, the force will be applied to the grinding wheel. A force acting in a direction perpendicular to the surface 11 and a force acting in a direction parallel to the grinding wheel surface 11 will act. As a result, even if a constant force is applied to the handle 2, a force that causes the grinding wheel surface 11 to naturally slide (force acting in a direction parallel to the grinding wheel surface 11) is exerted, so be especially conscious of the angle of the grinding wheel surface 11. Even without this, the angle of the grinding wheel surface 11 is stabilized. On the other hand, as shown in FIG. 14(b), if the hand-held knife sharpening tool Since the force only acts in the direction perpendicular to the surface 11, it is necessary to reciprocate the handle portion 2 while maintaining the angle at which the grindstone surface 11 contacts the cutting edge of the cutter (the angle of the cutting edge). Polishing work is forced while always being aware of the angle of the cutting edge, making it difficult to stabilize the angle of the cutting edge during polishing.

If the bending angle θ1 of the whetstone base portion 3 toward the whetstone surface 11 with respect to the central axis 2L of the handle portion 2 (the inclination angle of the whetstone surface 11 with respect to the central axis 2L of the handle portion 2) is too large, The force acting in the parallel direction (the force for sliding the grindstone 1) increases, causing an unintended movement for the operator when sharpening the scissors S, giving a sense of discomfort. This bending angle θ1 (the inclination angle of the whetstone base part 3 toward the whetstone fixing surface 3a side with respect to the central axis 2L of the handle part 2, that is, the inclination angle of the whetstone surface 11 with respect to the central axis 2L of the handle part 2) ) exceeds 25 degrees, it is difficult to perform a good polishing operation, according to the verification results. Furthermore, if the inclination angle θ1 of the grinding wheel surface 11 with respect to the central axis 2L of the handle part 2 is too large, the direction of pulling (returning) the grinding wheel 1 when pulling (returning) the grinding wheel 1 during polishing work in which the grinding wheel 1 is pushed and pulled is This means that an operating force in the opposite direction is applied, and when the angle of inclination of the grindstone surface 11 with respect to the central axis 2L of the handle portion 2 exceeds 25 degrees, it becomes extremely difficult to pull the grindstone 1 as described above.

In particular, according to the hand-held knife sharpener X according to the embodiment, the outward facing surface 3b (upward facing surface 2b) and both side surfaces of the whetstone base portion 3 are chamfered to make the head portion thin and compact. Therefore, it is possible to access the vicinity of the connecting part SC between the blades S1 and S2 of the scissors S, and it can fit on the blade edge S11 and perform polishing work smoothly.

Note that the present invention is not limited to the embodiments described above. For example, the material of the handheld portion and the grindstone base portion is not limited to aluminum, and may be constructed using another material. In addition, by configuring the whetstone base part to be replaceable with an attachment method in the hand-held part, different types of coarse whetstones and fine whetstones can be used depending on the condition of the object to be polished. It can be used. For example, check the condition of the blade, and if there are any chips or the like, you can first rough-finish it with a coarse grindstone, and then finish sharpen it with a fine-grit stone.

The angle of inclination of the grindstone surface with respect to the central axis of the hand-held portion may be changed as appropriate as long as it is within the range of 5 degrees to 25 degrees. The material of the whetstone is not particularly limited, and it may be a whetstone other than a diamond whetstone.

The number and presence of recesses for finger rests on the handle, the presence or absence of slanted surfaces for finger rest, the overall length and diameter of the handle, and the overall length, thickness, width, and shape of the whetstone base can be changed and set as appropriate. can. The grindstone base is required to have enough strength to prevent it from accidentally breaking or bending during polishing operations.

The knife sharpening tool according to the present invention can also be suitably used as a tool (tool) for sharpening the blades of knives mainly used for landscaping and gardening other than the blades of pruning shears described in the above-described embodiments.

In addition, the specific configurations and processing contents of each part are not limited to the above embodiments, and various modifications can be made without departing from the spirit of the present invention.

1...Whetstone 11...Whetstone surface 2...Handle part 2L...Central axis of handle part 3...Whetstone base part 3a...Whetstone fixing surface X...Hand-held knife sharpener

Claims (4)

A hand-held blade sharpening tool that can be sharpened with a whetstone provided at the tip in contact with a blade to be polished,
A handle part, which is the part that the operator holds during polishing work,
a grindstone base part that extends continuously from the handle part at a predetermined angle toward the tip side and has a surface facing the blade during polishing work as a grindstone fixing surface;
The hand-held blade sharpener is characterized in that the whetstone base part has a shape inclined at an angle of 5 to 25 degrees toward the whetstone fixing surface with respect to the central axis of the handle part. 2. The hand-held blade sharpener according to claim 1, wherein the whetstone base has a thickness that is set to gradually decrease toward the tip. 3. The hand-held blade sharpener according to claim 2, wherein the thickness of both side portions of the whetstone base portion is set to be gradually smaller toward the side edges. The hand-held blade sharpener according to claim 1, wherein the whetstone is constructed using a diamond whetstone.

Images