Rotary cutter for brush cutter

Abstract

To provide a rotary cutter having continuing stability in easiness of code exchange even after a long term usage.SOLUTION: A rotary cutter for a bush cutting machine having an exchangeable cord includes: a cord which rotates for cutting weeds and the like; a reel which houses the cord, and intermittently turns to deliver the cord; a case body for housing the reel; a cover for covering the case body; and a pushing body which protrudes from the case body, movable in an axial direction by being pushed, and intermittently turns the reel. A flange projection body having a recessed / projected shape is provided on an outer periphery surface of a reel flange of the reel. During cutting of the weeds, the flange projection body and the reel are housed in the cover. The recessed / projected shape is a shape for being held by a hand to turn the reel. On an outer side of the outer periphery surface having the recessed / projected shape, there is provided an area having no obstruction to motion of the hand when holding the recessed / projected shape to turn the reel.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a rotary cutter for a brush cutter, which is used to cut grass and the like using a cord (mainly made of nylon) extending radially from a case that is driven to rotate via a rotating shaft by the power of a motor or the like. [Background technology]

[0002] Conventionally, when the cord of this type of rotary cutter wears out and the cord stored in the reel becomes worn out, it is necessary to disassemble the rotary cutter, remove the reel, wind new cord on it, and reassemble the components.

[0003] However, with this method, when disassembling and removing the reel, related parts of the reel and other components are also removed at the same time, which increases the risk of losing these components. For this reason, there are rotary cutters that simplify the process of replacing worn-out cords, and rotary cutters that allow the cord to be replaced without disassembling and assembling the rotary cutter. For example, a rotary cutter has been proposed that has a through-hole drilled in the cylindrical part (cord winding part) of the reel, and the cord is passed through the through-hole and wound around the cylindrical part of the reel (see Patent Documents 1 to 3, etc.).

[0004] Furthermore, the rotary cutters described in these publications have a complex structure, which increases the manufacturing costs, and the operation of inserting and conducting the cord when winding the cord onto the reel takes time and effort. To solve this problem, a cord-replaceable rotary cutter is known in which recesses are provided in the reel to simplify manufacturing and processing, and there is no risk of losing the reel or related parts (see Patent Documents 4 and 5). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Utility Model Registration No. 2509199 [Patent Document 2] Japanese Patent Application Laid-Open No. 2005-124501 [Patent Document 3] Special Publication No. 2006-524837 [Patent Document 4] Japanese Patent Application Laid-Open No. 2009-207433 [Patent Document 5] Japanese Patent Application Laid-Open No. 2010-29075 Summary of the Invention [Problem to be solved by the invention]

[0006] However, with the above-mentioned conventional technology, as the rotary cutter is used to cut grass, the pressing body wears out, which causes a problem in that it becomes difficult to replace the cord (a task of turning it by hand). SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a rotary cutter that has continuous stability in terms of ease of cord replacement even when used for a long period of time. [Means for solving the problem]

[0007] The first invention of the present invention is a cord-replaceable rotary cutter for a brush cutter, which comprises: a cord that rotates to cut grass, etc.; a reel that stores the cord and reels out the cord while rotating intermittently; a case body that stores the reel; a cover that covers the case body; and a pressing body that protrudes from the case body, can move axially when pressed, and intermittently rotates the reel.The rotary cutter for a brush cutter is characterized in that it is provided with a flange protrusion that protrudes from the flange surface of the reel and has an uneven shape on its outer side, and during grass cutting, the flange protrusion and reel are stored in the cover, the uneven shape is a shape that can be grasped with fingers to rotate the reel, and there is an area outside the outer surface having the uneven shape that is free of obstacles to hinder finger movement when the uneven shape is grasped with fingers to rotate the reel.

[0008] The second invention of the present invention is a rotary cutter for a brush cutter, characterized in that the flange protrusion in the first invention is attached to the flange of the reel by any of a method of fixing, fastening, or fastening.

[0009] A third aspect of the present invention is a rotary cutter for a brush cutter, characterized in that the flange protrusion in the first aspect is integrally formed with the flange of the reel.

[0010] The fourth aspect of the present invention is a cord-replaceable rotary cutter for a brush cutter, which comprises: a cord that rotates to cut grass, etc.; a reel that stores the cord and reels out the cord while rotating intermittently; a case body that stores the reel; a cover that covers the case body; and a pressing body that protrudes from the case body, can move axially when pressed, and intermittently rotates the reel, and which has an uneven shape on the upper end of the pressing body. [Effects of the Invention]

[0011] According to the present invention, the flange protrusion and reel are stored within a cover during mowing, the uneven shape is a shape that can be grasped with fingers to rotate the reel, and there is a spatial area outside the outer surface having the uneven shape that does not cause rotational obstructions when the uneven shape is grasped with fingers to rotate the reel, making it easy to operate by hand, and since the reel flange does not wear out because it is stored within the cover during mowing, the cord replacement performance can be maintained even when mowing work is carried out for a long period of time. Furthermore, dust is less likely to accumulate inside the pressing body, which allows the pressing body to operate stably. Furthermore, the above-mentioned means also has the effect of improving the degree of freedom in designing the pressing body. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is an external view showing a rotary cutter for a brush cutter according to the present invention; [Figure 2] 2 is an external view showing the first embodiment of the reel 3 of the rotary cutter for brush cutters with the cover 2 removed. FIG. [Figure 3] FIG. 3 is a cross-sectional view taken along line AA in FIG. 2. [Figure 4] FIG. 1 is a side view showing the structure of a reel according to the present invention, in which (a) is a reel having a flange protrusion with an uneven shape on the top of the reel flange, and (b) is a reel having a flange protrusion with an uneven shape on the top and bottom of the reel flange. [Figure 5] 1A and 1B are diagrams showing another embodiment of the rotary cutter for a brush cutter according to the present invention, in which (a) is a cross-sectional view of the rotary cutter for a brush cutter according to the other embodiment, (b) is an external view showing the gaps in the pressing body, and (c) is an external perspective view showing the pressing body having an uneven shape at its upper end that protrudes upward from the surface of the upper end. [Figure 6] FIG. 10 is an external perspective view showing a pressing body according to another embodiment of the present invention, which has an uneven shape protruding upward from the surface of the upper end of a rotary cutter for a brush cutter. [Figure 7] FIG. 10 is an external perspective view showing a pressing body according to another embodiment of the present invention, which has an uneven shape protruding upward from the surface of the upper end of a rotary cutter for a brush cutter. DETAILED DESCRIPTION OF THE INVENTION

[0013] Figures 1 to 3 show an embodiment of a rotary cutter for a brush cutter according to the present invention, in which Figure 1 is an external view, Figure 2 is an explanatory view showing the internal structure with cover 2 removed, and Figure 3 is a cross-sectional view taken along line AA in Figure 2, in which RC is the rotary cutter, 1 is the case, 2 is the cover, 3 is the reel, 31T is the upper part of the reel flange, 31U is the lower part of the reel flange, 3-1 is the uneven shape of the reel flange protrusion, 4 is the pressing body, 8 is the cord guide, 9 is the cord, and S is an area free of obstacles that impede finger movement.

[0014] Therefore, the structure of a rotary cutter for a brush cutter according to one embodiment of the present invention shown in Figs. 1 to 3 will be first described. The rotary cutter RC for brush cutters of this embodiment uses a rotary cutter (pressure body) that strikes the rotary cutter to unwind the cord. Its structure is such that a reel 3, with a bottomed cylindrical pressure body 4 either integrally or separately provided, is mounted in the center of a case 1 so that the pressure body 4 protrudes below the case 1. Furthermore, a cord guide 8 is provided on the outer peripheral edge of the case 1.

[0015] In addition, the reel flange upper part 31T (see Figure 4(a)) of the reel shown in an embodiment in Figure 4, or the reel flange upper part 31T and reel flange lower part 31U (see Figure 4(b)), is provided with a flange protrusion 32 that protrudes from the surface of the upper part, or from the surfaces of the upper and lower parts, and has an uneven shape 3-1 on its outer side, and during mowing, the flange protrusion 32 and reel 3 are stored within cover 2, and the uneven shape 3-1 is shaped to be grasped with fingers to rotate the reel 3, and outside the outer surface having the uneven shape 3-1, there is provided an area S (see "symbol S" in Figure 3) that is free of obstacles that will hinder the movement of the fingers when the uneven shape 3-1 is grasped with fingers to rotate the reel 3.

[0016] Furthermore, the flange protrusion 32 is provided on the surface of the reel flange by any of methods of fixing, securing, or fastening, but is preferably fastened by fitting or using screws.

[0017] Also, the flange protrusion 32 may be manufactured as an integral part of the reel flange.

[0018] Furthermore, Figure 5 is a diagram showing another embodiment of the pressing body, in which the upper end 41 of the pressing body 40 may have an upper end uneven shape 42 that protrudes upward from the upper end surface 41A and is formed on the upper end circumference.

[0019] In addition, in other embodiments of the pressing body shown in Figures 6 and 7, the upper end portions 141, 241 of the pressing bodies 140, 240 are provided with upper end uneven shapes 142, 242 that have hardness or structure, or both, that do not interfere with the operation of the pressing bodies 140, 240. These upper end uneven shapes 142, 242 protrude upward from the upper end surfaces 141A, 241A and are attached to the pressing body as separate bodies by gluing, welding, insert molding, fastening, etc., in multiple numbers at equal intervals or randomly around the upper end circumference, or are provided in an integrated form by being integrally molded with the pressing body (same part).

[0020] When the rotary cutter for a brush cutter according to the present invention is used to carry out work, the pressing body is slammed into the ground to let out the cord, and when the pressing body is pressed, the uneven upper end shape 42, 142, 242 provided on the upper end 41, 141, 241 of such a pressing body has the effect of penetrating, particularly through the gap G of the pressing body, scraping out accumulated debris and discharging it through the gap (corresponding to the recess) formed by the uneven upper end shape, thereby stabilizing the operation of the pressing body. This action also acts when replacing the cord, stabilizing the operation of the pressing body. Furthermore, because of this effect, the rotary cutter for a brush cutter according to the present invention is less likely to accumulate dust inside, and the pressing body can operate stably.

[0021] The rotary cutter for brush cutters is structured so that the case 1 and reel 3, and the reel 3 and cover 2, are engaged with each other using a recess-projection fitting method, and when the pressing body 4 is slammed into the ground, the pressing body 4 is pushed inward, disengaging the case 1 and reel 3, causing the reel 3 to rotate and unwinding the cord (not shown) wound around the reel 3. The reel 3, which is pushed inward, engages with the cover 2 and stops rotating temporarily, but the elastic force of a built-in spring (not shown) causes it to return to its original position, and the case 1 and reel 3 are engaged again, securing the reel 3. The reel is connected to a drive shaft (not shown) of a motor or the like via a nut member fixed inside the cover 2.

[0022] When replacing a worn-out cord in the rotary cutter for brush cutters shown in FIGS. 1 to 7, the cover 2 is removed, and the central portion of a new cord of the desired length is inserted from above into the cord insertion groove of the empty reel 3 engaged in the case 1 and into the cord guide 8 aligned with the cord insertion groove. Then, with both ends of the cord projecting an appropriate distance from the cord guide 8, the operator grasps the pressure body 4, which is separate from the reel 3 or to which the reel 3 is rotatably attached, and manually rotates the reel 3, gripping it using the concave and convex shapes 3-1 on the outer circumferential side of the upper reel flange of the reel 3 or the flange protrusions 32 on the upper and lower reel flanges. This allows the cord 9 to be wound around the reel 3 quickly and easily. In addition, since the cord can be wound while the reel 3 is fixed to the case 1, the cord 9 can be easily and quickly attached to and wound around the reel 3. Furthermore, when replacing the cord, it is only necessary to remove the cover 2 as described above, and no other components need to be removed, so there is almost no risk of losing any of the rotary cutter's components. [Industrial Applicability]

[0023] The rotary cutter for brush cutters of the present invention has a structure that there is almost no risk of losing related parts of the reel or other components when replacing the cord, and the reel can be easily rotated by hand when winding the cord onto the reel, so that the cord can be attached to the reel easily and quickly, and the cord can be wound quickly and reliably.Furthermore, the structure is easy to manufacture and process, and the manufacturing cost is low. Therefore, the rotary cutter for a brush cutter of the present invention is extremely useful for cutting grass and weeds. [Explanation of symbols]

[0024] 1 case 2 Cover 3 reels 3-1 Concave and convex shape (on the side of the flange protrusion) 4, 40, 140, 240 pressing body 8 Chord Guide 9. Code 31U Reel flange bottom 31T reel flange top 32 Flange protrusion 41, 141, 241 Upper end of pressing body 41A, 141A, 241A Upper end surface of pressing body 42, 142, 242 Concave and convex shape of the upper end of the pressing body Gap between pressing bodies RC rotary cutter S An area where there are no obstacles that would hinder the movement of the fingers when spinning the reel 3 by hand.

Claims

1. In a cord-replaceable rotary cutter for brush cutters, The tool comprises a cord that rotates to cut grass and the like, a reel that stores the cord and reels out the cord while rotating intermittently, a case body that stores the reel, a cover that covers the case body, and a pressing body that protrudes from the case body and can be moved axially by being pressed, and that intermittently rotates the reel, The reel has a flange protrusion that protrudes from the reel flange surface and has an uneven outer circumferential side surface, and the flange protrusion and the reel are stored in a cover during mowing. The concave-convex shape is a shape that can be gripped with fingers to rotate the reel, A rotary cutter for a brush cutter characterized in that the outer peripheral surface having the uneven shape has an area outside which is free of obstacles that would hinder the movement of fingers when the uneven shape is gripped with fingers to rotate the reel.

2. 2. The rotary cutter for a brush cutter according to claim 1, wherein the flange protrusion is attached to the reel flange of the reel by any one of methods of fixing, fastening, and fastening.

3. 2. The rotary cutter for a brush cutter according to claim 1, wherein the flange protrusion is integral with a reel flange of the reel.

4. A rotary cutter for a brush cutter as described in claim 1, characterized in that the upper end of the pressing body is further provided with an uneven shape.

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