JP6077818B2 - Easy-to-remove rotary blade for brush cutter - Google Patents

Description

  The present invention relates to a rotary blade for a brush cutter that is provided with a large number of blade portions on the entire outer periphery of a disk-shaped pedestal and that is easy to attach and detach.

  2. Description of the Related Art Conventionally, a rotary blade for a brush cutter is formed by forming a disk-shaped pedestal using a metal plate, and providing cutting blades and carbide tips at predetermined intervals on the outer peripheral edge of the disk-shaped pedestal. In addition, a cemented carbide tip is widely used because it has better machinability than a metal cutting blade. On the other hand, a rotary blade for a brush cutter provided with a holding member that is attached to a brush cutter and is rotated and a nylon cord cutting blade having a base end held by the holding member is also widely used because it can be easily used.

  However, the conventional rotary blade using a disk-shaped pedestal made of a metal plate is abnormal because the vibration at the time of cutting propagates to the metal plate constituting the disk-shaped pedestal when it is rotated at a high speed and resonates. In addition, there is a problem that high metallic intense noise is generated and the working environment is remarkably deteriorated. On the other hand, since the nylon cord cutting blade is very worn, it has been necessary to frequently feed out or replace the nylon cord during the mowing operation. In order to solve these problems, a rotary blade using a disc-shaped base made of synthetic resin instead of a metal plate has been devised.

  For example, tip saws used for woodworking, cutting outer wall materials, and cutting metal materials as rotary blades for hand-held electric cutting machines and circular saws, etc. An engaging groove is formed on the surface to be engaged with a joining portion with the chip on the outer periphery of the pedestal, and the joining portion with each chip of the pedestal that is melted or semi-molten at the time of forming the pedestal is defined as an engaging groove for the chip. A chip saw having a rotating base made of engineering plastics, in which the chip is integrally fixed to the base in a state where it cannot be detached from the base, is disclosed (see Patent Document 1).

  In addition, it has a fitting hole in the center, and obtains a bottom part that is closer to the center by a predetermined length than the top part on the same straight line passing through the center of the fitting hole, and the top part and the bottom part are arcuate. And is divided into a plurality of parts by the top and bottom straight parts of the crossing straight line passing through the center of the insertion hole, and the outer side of each arc is a notch, and the top is the shortest than the longest part of the center of the insertion hole. The blade part is formed only in the arc part of about one-half or two-thirds until the part where the blade is not attached is a notch part, and the thickness of the entire cutting blade including the blade part is uniform. A synthetic resin cutting blade having a synthetic resin cutting blade is disclosed (see Patent Document 2).

  Further, a side groove along the circumferential direction of the disk-shaped mother plate is provided on the side surface of the carbide tip, and an annular connecting cable is placed in the side groove of each carbide chip, and the carbide chip and the connecting cable are connected to the disk-shaped mother cable. A cemented carbide chip mounting structure formed by bonding with a hard synthetic resin forming a plate is disclosed (see Patent Document 3).

Japanese Patent Laid-Open No. 5-401 Japanese Patent Publication No. 6-12 Japanese Utility Model Publication No. 2-15823

  The tip saw described in Patent Document 1 is provided with a plurality of blade tips arranged at positions corresponding to the joints between the pedestal and the blade tip in the injection mold of the pedestal when the rotary pedestal is molded. When molten or semi-molten engineering plastic is injected into the mold, the resin in the flow state flows into the engagement grooves of the blade tip and is in close contact with the grooves and the outer peripheral surface portions of the chips on both sides thereof. It is joined by Tamo. However, this tip saw was developed for woodworking, cutting of outer wall materials and metal materials, and was not suitable for use in mowing work.

  When the mowing operation is performed using the synthetic resin cutting blade described in Patent Document 2, the brush cutter is set to a medium speed rotation, and the rotation direction is a so-called blade group having a shape smaller than the cutout portion provided with no blade. The condition is that it is rotated so that it is in a stroking state. In addition, the cutting blade has a structure divided into three by a notch, and the cutting blade is formed only about half of the arc portion. Nevertheless, there is a problem that the impact transmitted to the operator when the cutting blade comes into contact with the plant is large.

  In the cemented carbide tip mounting structure described in Patent Document 3, since the connecting rope and the cemented carbide tip are joined to one side surface of the disk-shaped base plate, when receiving stress from the other side surface during mowing, There was a possibility that the connecting cord or the cemented carbide chip might be peeled off.

  Furthermore, when replacing the tip saw or rotary blade of Patent Documents 1 to 3, the tip saw or rotary blade must be removed from the drive shaft and a new tip saw or rotary blade must be attached, which is troublesome and has poor work efficiency. Met.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a rotary blade for a brush cutter that is lightweight, can be used for a long time, and is easily attached and detached.

The rotary blade for a brush cutter of the present invention is provided with an insertion hole for inserting the convex cylindrical portion of the attachment / detachment holder at the center of the disc-shaped pedestal, and the attachment / detachment holder is arranged on the circumference of the disc-shaped pedestal portion. A plurality of locking holes formed by a circle and an arc-shaped groove extending from the circle are provided at positions corresponding to the plurality of standing locking pins, and on the outer peripheral edge of the disk-shaped pedestal A large number of blade portions are provided over the entire circumference.

  The rotary blade for a brush cutter can be made of a thermoplastic synthetic resin. Among thermoplastic synthetic resins, in particular, polycarbonate has impact resistance, flexibility, and impact resistance and can be used for a long time. In addition, if the locking hole of the disk-shaped pedestal that is locked to the locking pin standing on the attachment / detachment holder is rotated in a circular direction from the arc-shaped groove, there is no need to remove it from the drive shaft as in the past. The rotary blade for a brush cutter can be easily removed from the attachment / detachment holder.

The rotary blade for a brush cutter according to the present invention includes a concave portion for mounting a carbide tip at a circumferential center portion of the blade portion, and a circular cord along the circumferential direction at a central portion in the thickness direction of each blade portion. A groove for mounting is formed. The circular cable has a diameter that can be inserted into a groove formed in the outer peripheral edge of the disk-shaped pedestal, and the circular cable is inserted into a recess provided on the outer peripheral edge of the disk-shaped pedestal. Carbide tip is inserted at the position. If this circular rope and the cemented carbide chip inserted into the circular rope are fitted into the recesses and grooves provided on the outer peripheral edge of the disk-shaped pedestal, it can be firmly fixed to the outer peripheral edge of the disk-shaped pedestal. it can. Further, since the vegetation is cut with a cemented carbide chip, the sharpness is remarkably improved as compared with a conventional synthetic resin rotary blade.

The rotary blade for a brush cutter according to the present invention has a fixing hole for fixing the disk-shaped pedestal portion at a position corresponding to a plurality of fixing pins mounted on the attachment / detachment holder on the circumference of the disk-shaped pedestal portion. It is characterized by being provided. Thereby, the said disk-shaped base part can be fixed to the said attachment / detachment holder, and can be rotated at high speed.

  The rotary blade for a brush cutter of the present invention uses a thermoplastic synthetic resin that is excellent in impact resistance, flexible, and strong in impact resistance, so that it is longer than conventional synthetic resin rotary blades. Can be used for a period. Further, when the locking hole of the disk-shaped pedestal that is locked to the locking pin standing on the attachment / detachment holder is rotated from the arc-shaped groove in the circular direction or from the circular direction to the arc-shaped groove direction, The rotary blade can be easily detached from the desorption holder. Further, the rotary blade for brush cutter can be securely fixed to the detachable holder by the fixing screw attached to the detachable holder.

  The rotary blade for a brush cutter according to the present invention can be obtained by inserting the circular cable and the cemented carbide chip inserted into the circular cable into the recess and groove provided on the outer peripheral edge of the disk-shaped pedestal. The cemented carbide tip can be firmly fixed to the outer peripheral edge. As a result, the vegetation is cut with the cemented carbide tip, so that the sharpness is remarkably improved as compared with the conventional synthetic resin rotary blade.

It is a top view of the rotary blade for brush cutters which shows this invention embodiment . Is an A-A enlarged sectional view of FIG. It is a top view which shows the circular cord of embodiment of this invention . It is the cemented carbide chip body of embodiment of this invention , (a) is front sectional drawing, (b) is a right view. It is front sectional drawing of the attachment / detachment holder used for this invention. 5 is an enlarged view of part B. The insertion state which mounts | wears with the attachment / detachment holder the rotary blade for brush cutters is shown. The fixed state of attaching the rotary blade for brush cutter to the attachment / detachment holder is shown.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, the same code | symbol is provided about the same member in each figure. The disc-like pedestal 1 used for the rotary blade for a brush cutter uses polycarbonate, which is a kind of thermoplastic resin. Polycarbonate is a resin having high physical properties among engineering plastics, is excellent in impact resistance and heat resistance, has features of being lightweight, difficult to deform, and easy to process. It is also possible to use engineering plastics such as polyacetal, polyimide, PPE, polybutylene terephthalate, and super engineering plastics such as polyarylate, polysulfone, polyphenylene sulfide, polyether ether ketone, polyimide resin, and fluororesin. Further, it is naturally possible to use a metal instead of the thermoplastic resin.

  In FIG. 1, the disc-like pedestal 1 is provided with an insertion hole 3 for inserting a convex cylindrical portion of a detachable holder, and is erected on the detachable holder on the circumference of the disc-shaped pedestal 1. A plurality of locking holes 11 formed by a circle 12 and an arcuate groove 13 extending from the circle 12 are provided at positions corresponding to the plurality of locking pins. On the circumference concentric with the locking hole 11, a fixing hole 14 is provided at a position corresponding to a pair of fixing screws 27 erected on the attachment / detachment holder. A large number of blade portions 2 are provided on the outer peripheral edge of the disk-shaped pedestal 1 over the entire circumference. The blade portion 2 and the disk-shaped pedestal 1 have the same thickness, and are integrally formed by resin injection molding or machining. Further, although it depends on the plate thickness, press punching can be performed.

The disc-shaped base 1 made of synthetic resin (for example, polycarbonate) has a concave portion 5 in which the carbide tip body 7 is mounted at the center portion in the circumferential direction of the blade portion 2, and a center in the thickness direction of each blade portion 2. A groove 10 for mounting the circular cord 8 along the circumferential direction is formed in the part. The circular cord 8 has a diameter that can be fitted into a groove 10 formed in the blade portion 2 on the outer peripheral edge of the disk-shaped pedestal 1, and is formed on the outer peripheral edge of the disk-shaped pedestal 1 as shown in FIG. 2 . The tip of the cemented carbide tip body 7 is inserted in a state where it protrudes from the blade portion 2 provided at the circumferential edge at a position where it is inserted into the provided recess 5.

  If the circular rope 8 and the cemented carbide tip body 7 inserted in the circular rope 8 are fitted into the recess 5 and the groove 10 provided on the outer peripheral edge of the disc-shaped base 1, the outer peripheral edge of the disc-shaped base 1 is obtained. It can be firmly fixed to. In addition, an adhesive may be used for fitting the circular cord 8 and the cemented carbide chip body 7, but insert molding may be performed when the disk-shaped pedestal 1 is molded. If the rotary blade for a brush cutter is formed in this manner, the vegetation is cut by the cemented carbide tip body 7, so that the sharpness is remarkably improved as compared with the conventional synthetic resin rotary blade.

In FIG. 3 , the circular cord 8 uses polycarbonate which is a kind of thermoplastic resin as in the case of the disk-shaped pedestal 1, but may be made of metal. The circular cord 8 has a diameter that can be fitted into a groove 10 formed in the blade portion 2 on the outer peripheral edge of the disk-shaped pedestal 1 and is formed in a ring shape having a foldable flexibility. As shown in FIG. 4 , a cemented carbide tip body 7 having a cutting edge function is inserted into the ring portion through a through hole 9 provided in the cemented carbide tip body 7 and fixed at a predetermined interval. .

In FIG. 5 , the attachment / detachment holder 20 is made of a non-metal such as aluminum, metal or synthetic resin, and is integrally formed by press molding or the like. The attachment / detachment holder 20 has a disk shape, and a driving shaft (not shown) of a brush cutter is inserted into an insertion hole 22 provided in the center of the substrate 21 and is screwed with a nut or the like. A donut-shaped convex portion 23 concentric with the insertion hole 22 is provided on the surface of the detachable holder 20 on which the brush cutter rotary blade is mounted, and a flange portion 25 is provided on the outer periphery of the convex portion 23. It has been. A plurality of locking pins 26 are erected on the circumference of the flange portion 25 at equal intervals on the circumference, and a pair (two) of the locking pins 26 are arranged at opposite positions on the circumference at the center. A screw hole is provided, and a fixing screw 27 is attached to the screw hole.

  The locking pin 26 includes a head portion 26a and a round bar 26b that supports the head portion 26a, and the head portion 26a is provided on the disk-shaped base 1 of the rotary blade for the brush cutter. Although the circle 12 of the stop hole 11 can pass, the arc-shaped groove 13 is formed in a hemisphere or curved surface having a diameter that cannot pass. The round bar 26 b has a diameter that can pass through the arc-shaped groove 13 of the locking hole 11, and adjusts the height protruding from the attachment / detachment holder 20 according to the plate thickness of the disk-shaped base 1. be able to.

As shown in FIG. 6 (a), fixing screws 27 provided in the screw hole is formed from a cylindrical portion extending from the threaded portion and the該螺Ko unit, typically, the thickness of the desorption holder 20 It is attached to. When the cutting払用rotary blade mounted on the desorption holder 20, the fixing hole 14 provided with the screw hole in the disc-shaped base 1 while being matched, the as shown in FIG. 6 (b) By screwing the fixing screw 27 into the fixing hole 14, the brush cutting rotary blade can be fixed to the attachment / detachment holder 20.

The procedure for attaching or detaching the rotary blade for mowing to or from the attachment / detachment holder 20 is as follows. When the brush cutter is mounted on the attachment / detachment holder 20, as shown in FIG. 7 , the disk-shaped pedestal portion 1 of the cutter blade at the position of the plurality of locking pins 26 provided on the attachment / detachment holder 20. The circles 12 of the plurality of locking holes 11 provided in are inserted correspondingly. Next, as shown in FIG. 8 , when the cutting blade is rotated until it comes into contact with the tip of the arc groove 13 of the locking hole 11, the cutting blade is fixed to the attachment / detachment holder 20. Next, the mowing rotary blade can be fixed to the attachment / detachment holder 20 by screwing the fixing screw 27 into the fixing hole 14 provided in the disc-like pedestal portion 1. Further, when removing the rotary blade for brush removal from the attachment / detachment holder 20, it can be removed by a procedure reverse to the above procedure.

  INDUSTRIAL APPLICABILITY The present invention can be widely used as a rotary blade for a brush cutter that replaces a conventional cord type brush cutter, a metal or synthetic resin rotary blade.

DESCRIPTION OF SYMBOLS 1 Circular base 2 Blade part 3 Insertion hole 5 Recessed part 7 Carbide tip body 8 Circular rope 9 Through hole 10 Groove 11, 11a Locking hole 12 Circle 13 Arc-shaped groove 14 Fixing hole 20 Desorption holder 21 Substrate 22 Insertion hole 23 Convex Part 24 outer peripheral part 25 collar part 26 locking pin 26a head part 26b round bar 27 fixing screw

Claims (1)

An insertion hole for inserting the convex cylindrical part of the attachment / detachment holder is provided in the center part of the disk-shaped pedestal made of synthetic resin ,
On the circumference of the disk-shaped pedestal, there is a locking hole formed by a circle and an arc-shaped groove extending from the circle at a position corresponding to the plurality of locking pins erected on the attachment / detachment holder. provided in plurality, the positions corresponding to the plurality of fixing screws mounted on the desorption holder, solid Teiana is provided for fixing the disc-shaped base,
In the outer peripheral edge of the disk-shaped pedestal, in a rotary blade for a brush cutter that is easy to attach and detach, provided with a large number of blade portions over the entire circumference ,
The blade part is provided with a recess in the center part in the circumferential direction of each blade part, and a groove is formed along the circumferential direction in the center part in the thickness direction of each blade part ,
All the recesses are fitted with a carbide chip body provided with a through hole,
A rotary blade for a brush cutter that is easy to attach and detach , wherein circular grooves formed in a circular shape penetrating through the through holes of the cemented carbide chip body are fitted in all the grooves .

Images