JP2015228800A - Rotary blade for grass mower, protection member for grass mower, and portable power grass mower - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary blade for grass mower, a protection member for grass mower, and a portable power grass mower, capable of reducing burden on a power source of the grass mower, improving cutting performance, and suppressing peripheral scatter of cut weeds, etc.SOLUTION: A rotary blade A1 for a grass mower includes: a holding member 1 attached to a rotary blade attachment shaft 44 of a grass mower B and rotated; and a cord-shaped cutting member 3 held by the holding member 1 on a base end side; and a protection member 2 rotated together with the holding member 1, extended on an outer side in a radial direction than the holding member 1 on a whole circumference in a circumferential direction of the rotation, and situated on an upper side than the cord-shaped cutting member 3. A part of the cord-shaped cutting member 3 in a tip side is projected on an outer side in the radial direction from the protection member 1 in a state of being extended on the outer side in the radial direction.

Description

  The present invention relates to a rotary blade for a mower, a protective member for a mower, and a portable power mower.

  There is a portable power mower as an instrument for removing weeds growing on the bank of a field. This mower is configured to transmit, for example, rotational power generated by a small engine to a rotary blade supported at the tip of an operation tube, and an operator can rotate the engine or the rotary blade rotated by the throttle lever. While controlling the rotation, the operation tube is shaken to perform a desired trimming operation.

  As a rotary blade, there is one in which a nylon cord cutting blade is radially extended from a central portion (see Patent Documents 1 and 2). 8 and 9 show an example of such a rotary blade. The illustrated rotary blade X is attached to the mower Y, and the nylon cord cutting blade 92 held by the holding member 91 rotates at high speed in the N direction together with the holding member 91 to cut weeds and the like. It is possible to be configured. According to such a configuration, even if the rotary blade X comes into contact with an object that is harder than weeds, such as stones, concrete pieces, or guardrail columns, the nylon cord cutting blade 92 has an appropriate flexibility. Since it has, it bends flexibly and does not produce a big impact force. Therefore, it can be avoided that the object is pulverized and the fragments are scattered around and the rotary blade X itself is damaged.

  However, the nylon cord cutting blade 92 has a higher peripheral speed and a higher cutting ability toward the tip in the rotational state, but the peripheral speed is slower at the base end portion, and the cutting ability is lower than the tip end portion. Inferior. As shown in FIG. 9, for example, when weeding the weed 93 having a thick and thick stalk, the weed 93 collides with a portion near the base end of the nylon cord cutting blade 92. . The portion near the base end of the nylon cord cutting blade 92 has insufficient cutting ability, so it is difficult to instantaneously cut the weed 93. On the other hand, in this case as well, the portion near the tip of the nylon cord cutting blade 92 has a relatively fast peripheral speed, and therefore continues to rotate in the circumferential direction due to its inertia. As a result, the nylon cord cutting blade 92 may be bent at the portion where the weed 93 collides, and the portion near the tip may be entangled around the weed 93. When this occurs, rotation of the rotary blade X is impeded by the weeds through the nylon cord cutting blade 92. Since a portable power mower is required to be able to work lightly on the back of an operator, the engine as a power source is also small and light and has a relatively low output. Therefore, the rotation of the rotary blade X may be stopped due to the rotation inhibition by the weeds 93 as described above. Even when the rotation of the rotary blade X does not stop, when the rotational speed of the rotary blade X decreases, the operator often tries to increase the rotational speed of the rotary blade X. If such work is continued, a high load is applied to the engine, which causes a problem that the engine does not operate normally.

  Further, even in the work of mowing soft weeds, there is a problem that the cut weeds are scattered around and the workability is lowered. Specifically, weed cutting is mainly performed by the portion near the tip of the nylon cord cutting blade 92, but the cut weed is shaken off by the entire exposed portion of the nylon cord cutting blade 92. The cut weeds are scattered around by the above-described swinging operation. When these weeds are sprinkled on the worker's feet or face, the mowing workability may be reduced.

JP 57-5608 A JP 2000-262126 A

  The present invention has been conceived under the circumstances described above, and reduces the load on the power source of the mower, improves the cutting ability, and the cut weeds scatter around. It is an object of the present invention to provide a rotary blade for a mower capable of suppressing this, a protective member for a mower, and a mower.

  The rotary blade for mower provided by the first aspect of the present invention includes a holding member that is attached to the rotary blade mounting shaft of the mower and is rotated, and a cord-shaped cutting member that is held on the base end side by the holding member. And a rotary blade for a mower provided with the holding member, and extending radially outwardly from the holding member in the entire circumferential direction of the rotation, and the cord-like cutting member The cord-shaped cutting member further protrudes radially outward from the protective member in a state where the cord-shaped cutting member extends radially outward. It is characterized by.

  In a preferred embodiment of the present invention, the protection member is configured separately from the holding member, and is detachable between the rotary blade mounting shaft and the holding member.

  In a preferred embodiment of the present invention, the protection member is located radially outward and has a fitting portion having a fitting hole at the center of rotation, and is fitted into the fitting hole, and the rotary blade mounting shaft and And a washer fixed to at least one of the holding members.

  In a preferred embodiment of the present invention, the flange portion is made of resin, and the washer portion is made of metal.

  In a preferred embodiment of the present invention, the fitting hole of the flange portion and the washer portion are configured such that a portion that is convex in the radial direction and a portion that is concave in the radial direction are alternately arranged in the circumferential direction. Yes.

  In a preferred embodiment of the present invention, the protection member is formed integrally with the holding member.

  The protective member for a mower provided by the second aspect of the present invention includes a holding member that is attached to a rotary blade mounting shaft of a mower and is rotated, and a cord-shaped cutting member that is held at the proximal end by the holding member. And a rotary blade for a mower provided with, and is detachable between the rotary blade mounting shaft and the holding member, and is rotated together with the holding member. It is characterized by being attached so as to extend outward in the radial direction from the holding member and to be positioned above the cord-like cutting member.

  In a preferred embodiment of the present invention, a flange portion that is located radially outward and has a fitting hole at the center of rotation, is fitted into the fitting hole, and includes at least the rotary blade mounting shaft and the holding member. And a washer portion fixed to either.

  In a preferred embodiment of the present invention, the flange portion is made of resin, and the washer portion is made of metal.

  In a preferred embodiment of the present invention, the fitting hole of the flange portion and the washer portion are configured such that a portion that is convex in the radial direction and a portion that is concave in the radial direction are alternately arranged in the circumferential direction. Yes.

  A portable power mower provided by the third aspect of the present invention includes an operation tube in which a transmission shaft to which a rotational output of a drive source is transmitted is inserted, and a rotary blade attachment formed at the tip of the operation tube A rotary mower provided with the first aspect of the present invention is attached to the rotary blade mounting shaft.

  According to such a structure, when the rotary blade for mowers is in a rotating state, only the distal end of the cord-like cutting member having the highest peripheral speed and its peripheral portion protrude from the protective member. . When the operator performs the mowing operation, the soft cutting object such as weeds reaches the peripheral edge of the protective member or before that, the tip of the cord-shaped cutting member that turns at a high speed as described above It is cut without difficulty by the part. On the other hand, when the cord-like cutting member collides with a relatively hard fixed object such as a stump or a concrete wall, the cord-like cutting member is bent and deformed, so that the rotation of the rotary blade is continued as it is. . In addition, the fixed object is not crushed and the fragments are scattered around, and the rotary blade itself is not damaged. And since the rotation of the rotary blade is continued as it is, the cutting action on weeds is immediately restored. Thus, even when a soft cutting object and a hard fixed object coexist, the mowing work can be performed efficiently.

  Further, since the portion near the base end of the cord-shaped cutting member does not protrude from the protective member, it does not collide with a cutting target such as weeds. For example, when weeds that have grown into a thick and thick stem collide with a portion near the base end of the cord-like cutting member, the cord-like cutting member is bent in this portion, and the tip portion is wound around the stem. It is possible to prevent entanglement and so on. Therefore, it is possible to prevent the rotation of the rotary blade due to the cord-shaped cutting member being entangled with the stem, and a high load is applied to, for example, a small engine that is a power source of the mower. Can be avoided.

  Furthermore, since only the portion near the tip of the cord-shaped cutting member protrudes from the protective member, for example, the cut weeds are shaken off by the entire cord-shaped cutting member and excessively around the periphery. Can be prevented from being scattered. In particular, the protective member is positioned above the cord-like cutting member over the entire circumference in the circumferential direction of rotation. As a result, when weeds scattered upward due to cutting fall, the protective member receives these weeds and suppresses these weeds from being blown off to the operator's feet or face by the cord-shaped cutting member. Therefore, the workability of mowing can be improved.

  Other features and advantages of the present invention will become more apparent from the detailed description given below with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS It is a whole perspective view which shows the rotary blade for mowers based on 1st embodiment of this invention, and the mower using the same. It is a principal part enlarged view of the rotary blade for mowers of FIG. 1, and a mower. It is principal part sectional drawing in the III-III line of FIG. It is a disassembled perspective view of the rotary blade for mowers of FIG. 1, and a mower. (A) which shows the flange part of the protection member of the rotary blade of FIG. 1 is a top view, (b) is sectional drawing which follows the VV line. (A) which shows the washer part of the protection member of the rotary blade of FIG. 1 is a top view, (b) is sectional drawing which follows a VI-VI line. It is principal part sectional drawing which shows the rotary blade for mowers based on 2nd embodiment of this invention, and the mower using the same. It is a whole perspective view of an example of the conventional rotary blade for mowers and a mower using the same. It is a principal part top view of the conventional rotary blade for mowers.

  Hereinafter, preferred embodiments of the present invention will be specifically described with reference to the drawings.

  1 to 3 show a rotary blade for a mower according to a first embodiment of the present invention and a mower using the same. As clearly shown in FIG. 1, in the mower B, a small engine 41 as a drive source is connected to the proximal end side of the operation tube 42, and the rotation output thereof is internal to the operation tube 42. It is configured to be transmitted to the distal end portion of the operation tube via the inserted transmission shaft 43. As the engine 41, for example, an engine having a displacement of about 25 cc is used in consideration of the portability of the operator. A small engine may be directly attached to the proximal end of the operation tube 42, or an engine mounted on a backpack frame, for example, may be connected via a flexible transmission shaft. As clearly shown in FIG. 3, a rotary blade mounting shaft 44 is supported on the gear case 45 at the tip of the operation tube 42. The rotary blade mounting shaft 44 and the transmission shaft 43 are connected to a bevel gear mechanism (not shown). It is linked by.

  The rotary blade mounting shaft 44 is attached with a rotary blade A1 for a mower characterized as follows. A rotary blade A1 for a mower according to the present invention includes a holding member 1, a protective member 2, and two nylon cord cutting blades 3.

  The holding member 1 has a flat cylindrical shape and is fastened to the rotary blade mounting shaft 44 by a bolt 16 provided at the center of the upper end thereof. Although the dimension of the holding member 1 is not particularly limited, for example, the diameter is about 110 mm and the height is about 40 mm, for example.

  In the present embodiment, the holding member 1 has an upper case 11, a lower case 12, a spring 13, two openings 14 and a lid 15. The upper case 11 and the lower case 12 are combined so as to be slidable in the vertical direction. The spring 13 is disposed so as to be interposed between the upper case 11 and the lower case 12, and biases an elastic force that separates the upper case 11 and the lower case 12 in the vertical direction. The two openings 14 are for exposing the two nylon cord cutting blades 3 to the outside. The lid portion 15 is a member that is disposed above the lower case 12 and that receives a fastening force for attaching the holding member 1 to the rotary blade attachment shaft 44.

  A long nylon cord is wound and housed inside the upper case 11 and the lower case 12 of the holding member 1, and the end portion drawn out of the holding member 1 through the opening 14 is the cord of the present invention. Nylon cord cutting blade 3 as a shape cutting member. The holding member 1 incorporates a nylon cord feed mechanism (not shown), and when the operator hits the ground with the bottom of the holding member 1 during work, the elastic force of the spring 13 is resisted. The upper case 11 and the lower case 12 approach each other. By this approach, the clutch mechanism (not shown) that fixes the upper case 11 and the lower case 12 is instantaneously released. At this time, the nylon cord is sent out by a predetermined length using the impact force and centrifugal force of the impact, and the nylon cord cutting blade 3 is extended. Such a combination structure of the holding member 1 and the nylon cord cutting blade 3 is disclosed in, for example, Patent Documents 1 and 2 cited as the prior art, and is well known.

  The two nylon cord cutting blades 3 are provided so as to extend radially outward from the holding member 1, respectively. These nylon cord cutting blades 3 correspond to an example of a cord-like cutting member in the present invention. The diameter of the nylon cord cutting blade 3 is not particularly limited, but is about 3 mm, for example. Note that the number of nylon cord cutting blades 3 can be changed, and one or three or more nylon cord cutting blades 3 may be provided. The nylon cord cutting blade 3 has a distal end portion 31 and a proximal end portion 32. The distal end portion 31 is an end portion located radially outward of the nylon cord cutting blade 3. The proximal end portion 32 is a portion that is located radially inward of the nylon cord cutting blade 3 and is close to the holding member 1.

  The protection member 2 is a disk-like member as a whole, and extends outward in the radial direction from the holding member 1 over the entire circumference. Further, the protection member 2 is installed so as to be interposed between the holding member 1 and the rotary blade mounting shaft 44. That is, in the use state shown in FIGS. 1 to 3, the protection member 2 is positioned above the two nylon cord cutting blades 3 extending from the holding member 1 in the entire circumferential direction. Note that the protective member 2 is not positioned vertically above the nylon cord cutting blade 3 when the mower B is laid on the ground when not in use or is swung up when in use. In the present invention, the relationship that the protective member 2 is positioned above the nylon cord cutting blade 3 is mainly used when the protective member 2 is disposed between the holding member 1 and the rotary blade mounting shaft 44. Means that the protective member 2 is positioned above the nylon cord cutting blade 3. Although the magnitude | size of the protection member 2 is not specifically limited, In this embodiment, the diameter is about 200 mm, for example.

  In the present embodiment, the protection member 2 is separate from the holding member 1, and is sandwiched between the holding member 1 and the rotary blade mounting shaft 44, so that the protective member 2 is separated from the rotary blade mounting shaft 44. The holding member 1 is fixed integrally. For this reason, when the rotary blade mounting shaft 44 rotates, the holding member 1 and the protection member 2 rotate integrally. In the present embodiment, the protective member 2 includes a flange portion 21 and a washer portion 27.

  The flange portion 21 is a portion having a disk shape, and is made of, for example, a resin containing glass fiber. In the present embodiment, as shown in FIGS. 3 and 5, the flange portion 21 includes a flat plate portion 23, a step portion 24, a proximity portion 25, and an outer peripheral portion 26. The flat plate portion 23 is located at the innermost position in the radial direction, and is a flat plate-like portion positioned between the rotary blade mounting shaft 44 and the holding member 1. In the present embodiment, the flat plate portion 23 is formed with a fitting hole 22. The fitting hole 22 is for fitting with the washer portion 27. In particular, for the purpose of strengthening the fitting with the washer portion 27 in the circumferential direction, the fitting hole 22 of the present embodiment has a portion convex in the radial direction and a portion concave in the radial direction alternately in the circumferential direction. It is the shape arranged in. In the illustrated example, four convex portions and four concave portions are alternately arranged. The step portion 24 is a portion that is connected to the outer side in the radial direction of the flat plate portion 23, and forms a step that is positioned downward as it goes outward in the radial direction. The proximity portion 25 is a portion connected to the outside in the radial direction of the step portion 24, and is located at the lowest position in the flange portion 21. Accordingly, the proximity portion 25 is a portion of the flange portion 21 that is closest to the nylon cord cutting blade 3. The outer peripheral portion 26 is connected to the outside of the proximity portion 25 in the radial direction, and is a portion thicker than the proximity portion 25 and the like.

  The washer portion 27 is a member that is located on the innermost radial direction of the protection member 2 and includes a rotation center. In the present embodiment, the washer portion 27 is formed of a metal that is harder than the flange portion 21. As shown in FIGS. 3 and 6, in the present embodiment, the washer portion 27 has a fixing portion 28 and a fitting portion 29. The fixing portion 28 is a flat plate-like portion located inward in the radial direction, and is a portion that is directly sandwiched between the holding member 1 and the rotary blade mounting shaft 44 and directly receives the fastening force by the bolt 16. The fixed portion 28 is provided with a hole through which the rotary blade mounting shaft 44 is inserted. The hole may be processed to engage with the rotary blade mounting shaft 44. The fitting portion 29 is connected to the outside in the radial direction of the fixed portion 28 and is a portion that fits into the fitting hole 22 of the flange portion 21. In the present embodiment, corresponding to the shape of the fitting hole 22 described above, the fitting portion 29 has a configuration in which a plurality of convex portions and a plurality of concave portions are alternately arranged in the circumferential direction. . In the present embodiment, the fixed portion 28 and the fitting portion 29 are in a relationship slightly shifted in the vertical direction.

  As shown in FIG. 3, in this embodiment, the length L1 of the portion of the nylon cord cutting blade 3 extending from the outer edge in the radial direction of the protection member 2 is the same as that of the outer end of the holding member 1 in the radial direction. It is set as the structure shorter than the length L2 with the radial direction outer edge of the member 2. As shown in FIG.

  FIG. 4 shows a procedure for attaching the rotary blade A1 for the mower to the mower B. In the illustrated state, the mower B is placed in a posture that is upside down from the use state. First, the rotary blade mounting shaft 44 is inserted through a hole provided in the fixed portion 28 of the washer portion 27. Further, the fitting hole 22 of the flange portion 21 is fitted into the fitting portion 29 of the washer portion 27. Next, the holding member 1 is lowered from above the protective member 2 and combined with the rotary blade mounting shaft 44. Then, the holding member 1 and the protection member 2 are fixed to the rotary blade mounting shaft 44 by fastening the bolt 16 to the rotary blade mounting shaft 44. Thereby, the mower B provided with the rotary blade A1 for the mower is completed.

  Next, the operation of the rotary blade A1 for the mower and the mower B using the same will be described.

  For example, when the throttle opening of the engine 41 is increased by operating the throttle lever, the rotary blade A1 for the mower at the tip of the operation tube 42 is rotated in the N direction in FIG. . By adjusting the throttle opening of the engine 41, the rotational speed of the rotary blade A1 for the mower can be adjusted. The rotational output of the engine 41 is decelerated from the transmission shaft 43 by a bevel gear (not shown) in the gear case 45 and transmitted to the rotary blade A1 for the mower. The rotational speed of the rotary blade A1 for the mower reaches, for example, 5,000 to 6,300 rpm, and the dimension from the rotational center of the rotary blade A1 for the mower to the tip 31 of the nylon cord cutting blade 3 is, for example, about 125 mm. The peripheral speed of the tip 31 of the nylon cord cutting blade 3 reaches 300 km / h. When the rotary blade A1 for mowing machine that rotates at high speed is moved along the ground in this way, relatively soft and thin objects such as weeds come into contact with the peripheral edge of the protective member 2 or before In this way, the nylon cord cutting blade 3 revolving at a high speed is subjected to a strong collision in the lateral direction by the tip portion 31 and is cut without difficulty by the impact. As described above, the nylon cord cutting blade 3 has a diameter of about 3 mm at most and is lightweight. However, since the turning speed is high as described above, the nylon cord cutting blade 3 is used for cutting soft stalks such as weeds. Has sufficient kinetic energy.

  Further, the weed cut as described above is shaken off by the nylon cord cutting blade 3 that rotates at high speed. However, only the portion closer to the distal end of the nylon cord cutting blade 3 including the distal end portion 31 protrudes from the protection member 2, and the portion closer to the proximal end including the proximal end portion 32 is configured to overlap the protection member 2. . For this reason, the cut weed is only shaken off by the front end portion 31 and its peripheral portion, and is not shaken off by the entire nylon cord cutting blade 3 as in the prior art. Therefore, it is possible to avoid that the cut weeds are scattered excessively in the surrounding area, and the workability is prevented by preventing the cut weeds from being sprinkled on the operator's feet and face. Can be improved. In particular, since the protective member 2 is positioned above the nylon cord cutting blade 3, the weed cut by the tip 31 of the nylon cord cutting blade 3 is swung up into the air and then moved to the rotary blade A1 for the mower. Even if it falls down, this weed is received by the protective member 2. For this reason, it can prevent that the cut weed is scattered widely by the nylon cord cutting blade 3 whole.

  Moreover, when the rotary blade A1 for mowers is moved toward the weeds that have grown to be thick and thick, the tip 31 and the weeds collide with each other. When the weed stalk grows to a certain extent even by the tip 31, the nylon cord cutting blade 3 is deformed, or the weed comes into contact with the periphery of the protection member 2. Even in such a case, since the length L1 of the portion protruding from the protective member 2 is shorter than the length L2 of the portion overlapping the protective member 2, the tip end 31 of the nylon cord cutting blade 3 becomes a weed. When it collides, it is immediately deformed, and the tip portion 31 passes through the weeds by this deformation. Therefore, there is no possibility of the nylon cord cutting blade 3 being entangled so as to wind around the weeds, and the rotation of the rotary blade A1 for the mower can be stabilized. If it does so, it can avoid that an excessive load is added to the engine 41 resulting from such winding of the nylon cord cutting blade 3, and the engine 41 can be operated normally. In addition, when mowing a place where only relatively soft weeds grow, the nylon cord cutting blade 3 protrudes because there is little possibility that the nylon cord cutting blade 3 is wound as described above. The length L1 of the portion may be longer than the length L2 of the portion overlapping the protective member 2 of the nylon cord cutting blade 3.

  Furthermore, in this embodiment, the protection member 2 is configured separately from the holding member 1. Therefore, for example, in FIG. 4, a configuration method is possible in which the holding member 1 that is already obtained and used is temporarily detached from the mower B, and the protection member 2 purchased later is attached to the mower B together with the holding member 1. Become. Thus, if only one type or a limited type of protective member 2 is prepared for a plurality of types of holding members 1 suitable for various cutting locations, the rotary blade A1 and the grass cutter B having the above-described configuration are prepared. Can be completed. In particular, even if the holding member 1 is not originally intended to be attached to the protection member 2, the structure that is attached to the rotary blade attachment shaft 44 is generally in the form described above from the viewpoint of versatility. For this reason, the protection member 2 in the form of being installed between the holding member 1 and the rotary blade mounting shaft 44 has an advantage that it can be used with more types of holding members 1. In addition, this arrangement is reasonable because the protective member 2 is positioned above the nylon cord cutting blade 3 in the use state.

  Since the protection member 2 includes the flange portion 21 and the washer portion 27, even if the fastening force of the bolt 16 is exerted strongly by the metal washer portion 27, a situation where the washer portion 27 is unduly crushed can be avoided, and the protection member 2 can be prevented. 2 can be firmly attached to the rotary blade attaching shaft 44 and the holding member 1. On the other hand, if the flange portion 21 that can come into contact with weeds, stones, structures and the like is formed of resin in the radially outward direction, excessive noise and damage are caused even when the protective member 2 comes into contact with various objects during mowing. There is little fear. Further, the fitting hole 22 of the flange portion 21 and the fitting portion 29 of the washer portion 27 are fitted, so that the rotational driving force from the rotary blade mounting shaft 44 is reliably transmitted to the flange portion 21 via the washer portion 27. Can tell. In particular, the configuration in which the fitting hole 22 and the fitting portion 29 are alternately arranged with a plurality of convex portions and a plurality of concave portions in the circumferential direction is a flange portion 21 and a washer portion 27 formed of different materials. Therefore, it is suitable for reliably transmitting the rotational driving force.

  FIG. 7 shows another embodiment of the present invention. In these drawings, the same or similar elements as those in the above embodiment are denoted by the same reference numerals as those in the above embodiment.

  FIG. 7 shows a rotary blade for a mower and a mower using the same according to the second embodiment of the present invention. The rotary blade A2 for mower of the present embodiment is different from the above-described embodiment in that the protective member 2 is formed integrally with the holding member 1.

  The protection member 2 of the present embodiment is configured as a part of the lid portion 15 of the holding member 1. That is, a part of the lid portion 15 located above the upper case 11 and the lower case 12 extends over the entire circumference in the circumferential direction outward in the radial direction. The protection member 2 of the present embodiment has portions corresponding to the flat plate portion 23, the step portion 24, the proximity portion 25, and the outer peripheral portion 26 in the flange portion 21 of the protection member 2 described above. When the protection member 2 is configured integrally with the lid portion 15, the lid portion 15 (protection member 2) is preferably formed of the above-described resin containing glass fiber, but is not limited to this and is various. It can be formed of any material.

  According to such an embodiment as well, it is possible to reduce the load on the power source of the mower, improve the cutting ability, and suppress the cut weeds from being scattered around. Further, since the protection member 2 is a dedicated product for the holding member 1, for example, the size and shape of the protection member 2 are more suitable for the holding member 1 and the nylon cord cutting blade 3 extending therefrom. It can be. For example, the protective member 2 25 can be configured closer to the nylon cord cutting blade 3.

  The rotary blade for mower according to the present invention and the portable power mower using the same are not limited to the above-described embodiments. The specific configuration of each part of the rotary blade for mower according to the present invention and the portable power mower using the same can be varied in design in various ways.

  As the holding member, it is convenient to have a nylon cord cutting blade feeding mechanism as in the above embodiment, but the holding member is not limited to this. For example, a nylon cord cutting blade having a desired length is provided on a disk-shaped member. It may be a fixed configuration.

B Mower A1, A2 Rotary blade for mower 1 Holding member 11 Upper case 12 Lower case 13 Spring 14 Opening portion 15 Cover portion 16 Bolt 2 Protection member 21 Flange portion 22 Fitting hole 23 Flat plate portion 24 Step portion 25 Proximity portion 26 Outer peripheral portion 27 Washer portion 28 Fixing portion 29 Fitting portion 3 Nylon cord cutting blade 31 Tip portion 32 Base end portion 41 Engine 42 Operation tube 43 Transmission shaft 44 Rotary blade mounting shaft 45 Gear case

Claims (11)

A holding member that is attached to the rotary blade mounting shaft of the mower and rotated;
A cord-like cutting member having a proximal end held by the holding member, and a rotary blade for a mowing machine,
It is rotated together with the holding member, and further includes a protective member that extends outward in the radial direction from the holding member and is positioned above the cord-like cutting member in the entire circumferential direction of the rotation.
The rotary blade for a mowing machine, wherein the cord-shaped cutting member has a part on the tip side protruding radially outward from the protective member in a state of extending radially outward.   The rotary blade for a mower according to claim 1, wherein the protection member is configured as a separate body from the holding member and is detachable between the rotary blade mounting shaft and the holding member.   The protection member is located radially outward and has a flange portion having a fitting hole at the center of rotation, and is fitted into the fitting hole, and is fixed to at least one of the rotary blade mounting shaft and the holding member. The rotary blade for a mower according to claim 2, comprising a washer portion.   The rotary blade for a mower according to claim 3, wherein the flange portion is made of resin, and the washer portion is made of metal.   The fitting hole of the said flange part and the said washer part are the parts which are convex in radial direction, and the part which is concave in radial direction are arrange | positioned alternately by the circumferential direction of Claim 3 or 4. Rotary blade for mowers.   The rotary blade for a mower according to claim 1, wherein the protection member is configured integrally with the holding member. Used with a rotary blade for a mower provided with a holding member that is attached to a rotary blade attachment shaft of a mower and rotated, and a cord-like cutting member that has a proximal end held by the holding member,
It is detachable between the rotary blade mounting shaft and the holding member,
It is rotated together with the holding member, and is attached so as to extend outward in the radial direction in the entire circumferential direction of the rotation from the holding member and to be positioned above the cord-like cutting member. Protective member for mower.   A flange portion located radially outward and having a fitting hole at the center of rotation; a washer portion fitted into the fitting hole and fixed to at least one of the rotary blade mounting shaft and the holding member; The protective member for mowers of Claim 7 containing this.   The protective member for a mower according to claim 8, wherein the flange portion is made of resin, and the washer portion is made of metal.   10. The fitting hole of the flange portion and the washer portion, according to claim 8 or 9, portions that are convex in the radial direction and portions that are concave in the radial direction are alternately arranged in the circumferential direction. Protective member for mowers. An operation tube in which a transmission shaft for transmitting the rotational output of the drive source is inserted;
A rotary blade mounting shaft formed at the tip of the operation tube, and a mower comprising:
A portable power mower, characterized in that the rotary blade for mower according to any one of claims 1 to 6 is attached to the rotary blade attachment shaft.

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