JP2019054753A - Mower - Google Patents

Abstract

To provide a mower using a simple and light-structured speed reduction mechanism.SOLUTION: The mower is equipped with a drive part, an upper blade and a lower blade, and a speed reduction mechanism. The speed reduction mechanism includes: a first to third speed reduction mechanisms in which the first speed reduction mechanism has three spur gears, in which the second speed reduction mechanism has a first pinion gear and a bevel gear, and in which the third speed reduction mechanism has a second pinion gear that rotates by the bevel gear, and an upper and a lower bevel gears that are vertically arranged in a manner holding the second pinion gear vertically in between with a gear shaft as a central axis. The upper blade rotates by the rotation of the lower bevel gear, and the gear shaft rotates by the upper bevel gear. The lower blade is installed in the lower end of the gear shaft and, by the rotation of the lower blade through the rotation of the upper bevel gear, the upper blade and the lower blade rotate in the directions opposite to each other.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a mower used for mowing work or the like.

  As a mowing apparatus used for mowing work, a brush cutter having a structure in which a blade rotating in one direction is provided at the front end of the hook and the blade is rotated by a driving unit provided at the rear end of the hook (see Patent Document 1). ) Are used in large numbers. Since conventional brush cutters have a structure in which the blade is rotated in one direction to cut grass, etc., the rotation of the blade causes pebbles and the like to scatter and hit the operator and the surrounding people and objects. Yes. In order to solve such a problem, when a brush cutter is used in an urban area or the like, a protective fence may be used.

  In order to solve the problem of scattered matter caused by such a brush cutter, a mowing device (Patent Documents 2 to 4) having a structure in which two blades are arranged one above the other and rotated in opposite directions is used. . Such a mowing apparatus using two blades has a structure in which the two blades rotate in opposite directions and cut an object with scissors, thereby cutting the grass. Can be prevented, and the mowing work can be performed safely.

  A conventional mowing apparatus using two blades has a structure in which the rotational force from a driving unit such as an engine is reduced to about 1/20 and the two blades are rotated in opposite directions. Various speed reduction mechanisms are used. Patent Document 2 describes a structure in which a bevel gear is used to change the direction of about 120 ° with respect to the kite, and then the speed is reduced by the sun gear and the ring gear to rotate the two blades in the opposite directions.

  Patent Document 3 describes a structure in which a bevel gear is used to change the direction about 120 ° with respect to the kite, and then the speed is reduced by two sets of spur gears and the two blades are rotated in opposite directions. Patent Document 4 describes a structure in which two blades are reciprocated at low speed to move in opposite directions by using a link mechanism.

JP 2014-117259 A JP 11-253027 A JP 2010-63452 A Japanese Patent Laid-Open No. 7-107837

  The conventional mowing apparatus using two blades uses a complicated structure or a large gear in order to decelerate the rotation by the drive unit, resulting in problems of weight and cost increase due to the decelerating mechanism. In addition, a mowing apparatus using two blades requires the tips of the two blades to be in close contact with each other in order to cut the grass or the like with the two blades. There is a problem that decreases.

  Accordingly, an object of the present invention is to provide a mower having a light weight and a large reduction ratio and having an excellent cutting ability in order to solve the conventional problems.

  The mowing machine of the present invention includes a drive unit that generates a rotational force, an upper blade and a lower blade that are rotated by the rotational force, a rotational force of the drive unit that is decelerated and transmitted to the upper blade and the lower blade and in opposite directions. A speed reduction mechanism for rotating the drive unit, a drive unit on the proximal end side, and a speed reduction mechanism on the distal end side, and a drive shaft for transmitting the rotational force of the drive unit to the reduction mechanism in the tube, A mowing machine including a collar portion inclined downward to the side and an operation portion for operating the upper blade and the lower blade, wherein the speed reduction mechanism includes a first speed reduction mechanism provided in a gear case, a second speed reduction mechanism, The first reduction mechanism has three spur gears located at the tip of the drive shaft, and the second reduction mechanism has a first pinion gear and a bevel gear. At the same time as the deceleration by the drive shaft The third reduction mechanism is arranged vertically so as to sandwich the second pinion gear from above and below, with the second pinion gear rotated by the bevel gear and the gear shaft as the central axis. An upper bevel gear and a lower bevel gear are provided, and at the same time as the speed is reduced, the central axis of rotation is changed from horizontal to vertical, the lower bevel gear is disposed so as to be rotatable with respect to the gear shaft, and the upper blades The upper blade is rotated by the rotation of the lower bevel gear, the gear shaft is rotated by the upper bevel gear, and the lower blade is attached to the lower end of the gear shaft. The lower blade is rotated by the rotation of the upper bevel gear. And wherein the rotating in opposite directions to the blade and the lower knife.

  The reduction ratio of the first reduction mechanism is 1/4, the reduction ratio of the second reduction mechanism is 1 / 1.6, the reduction ratio of the third reduction mechanism is 1/3, and The shaft angle of the bevel gear is 30 °.

  The gear case is vertically divided into two parts and is configured to be detachable from each other.

  The upper blade has a main body portion and a plurality of cutting edges arranged at equal intervals on the outer periphery of the main body portion, the main body portion is curved so that the center protrudes upward, and the cutting edge is downward The lower blade has a main body portion and a plurality of blade tips arranged at equal intervals on the outer periphery of the main body portion, and the main body portion projects downward in the center. The cutting edge has an inclined surface that is inclined upward, and when the upper blade and the lower blade rotate, the lower end of the inclined surface of the upper blade and the upper end of the inclined surface of the lower blade are mutually Abut.

  The mowing machine of the present invention is a reduction mechanism in which the mowing machine of the present invention decelerates the rotational force of the drive unit, the upper blade and the lower blade, and the drive unit and transmits them to the upper blade and the lower blade to rotate in opposite directions. A mowing machine including a collar portion having a drive shaft for transmitting the rotational force of the drive portion to the speed reduction mechanism, and an operation portion, wherein the speed reduction mechanism includes a first speed reduction mechanism provided in a gear case. A mechanism, a second speed reduction mechanism, and a third speed reduction mechanism, wherein the first speed reduction mechanism has three spur gears positioned at a tip of the drive shaft, and the second speed reduction mechanism is a first speed reduction mechanism. Having a pinion gear and a bevel gear, and simultaneously decelerating, the central axis of rotation by the drive shaft is changed in the horizontal direction, and the third reduction mechanism has a second pinion gear rotated by the bevel gear and a gear shaft as a central axis. Above It has an upper bevel gear and a lower bevel gear that are arranged vertically so as to sandwich a two-pinion gear from above and below. The upper blade is connected to the lower bevel gear so as to transmit a rotational force. The upper blade is rotated by the rotation of the lower bevel gear, and the gear shaft is rotated by the upper bevel gear. The lower blade is attached to the lower end of the gear shaft, the lower blade is rotated by the rotation of the upper bevel gear, and the upper blade and the lower blade are rotated in directions opposite to each other, It is possible to realize a mower having a large speed reduction ratio and a light speed reduction mechanism.

  The reduction ratio of the first reduction mechanism is 1/4, the reduction ratio of the second reduction mechanism is 1 / 1.6, the reduction ratio of the third reduction mechanism is 1/3, and By setting the shaft angle of the bevel gear to 30 °, a reduction ratio of about 1/20 can be obtained without using a large gear.

  The gear case is vertically divided into two parts and is configured to be detachable from each other, so that the gear case can be reduced in weight and the weight of the tip of the mower can be reduced.

  The upper blade has a main body portion and a plurality of cutting edges arranged at equal intervals on the outer periphery of the main body portion, the main body portion is curved so that the center protrudes upward, and the cutting edge is downward The lower blade has a main body portion and a plurality of blade tips arranged at equal intervals on the outer periphery of the main body portion, and the main body portion projects downward in the center. The cutting edge has an inclined surface that is inclined upward, and when the upper blade and the lower blade rotate, the lower end of the inclined surface of the upper blade and the upper end of the inclined surface of the lower blade are mutually By abutting, excellent cutting ability can be realized.

The perspective view of the mower of this invention. The perspective view of the reduction mechanism, the upper blade, and the lower blade of a mower. Sectional drawing of the speed-reduction mechanism of FIG. 2, an upper blade, and a lower blade. Sectional drawing of a 1st deceleration mechanism and a 2nd deceleration mechanism. Sectional drawing of a 2nd deceleration mechanism and a 3rd deceleration mechanism. The perspective view of the state which decomposed | disassembled the deceleration mechanism. (A) is a top view of an upper blade, (b) is a bottom view of a lower blade.

  The mower 1 of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a perspective view of the mower 1 of the present invention, FIG. 2 is a perspective view of the speed reduction mechanism 3, the upper blade 4 and the lower blade 5 of the mower 1, and FIG. 3 is the speed reduction mechanism 3 and the upper blade 4 of FIG. FIG. 6 is a cross-sectional view of the lower blade 5.

  As shown in FIG. 1, the mower 1 of the present invention reduces the rotational force of the drive unit 2 that generates rotational force, the upper blade 4 and the lower blade 5 that rotate by the rotational force, and the drive unit 2, A reduction mechanism 3 that transmits the upper blade 4 and the lower blade 5, a flange 6 that has a drive shaft 9 that transmits the rotational force of the drive unit 2 to the reduction mechanism 3, and the upper blade 4. And the operation part 7 which operates the said lower blade 5 is provided, and the grass can be cut by operating the said operation part 7 and rotating the said upper blade 4 and the said lower blade 5 in a mutually reverse direction.

  The drive unit 2 includes, for example, a small engine that generates a rotational force. The operation unit 7 is used to operate the mower 1 and is provided with a structure for operating the drive unit 2 such as on / off. The flange portion 6 is provided with the driving portion 2 on the proximal end side and the speed reduction mechanism 3 on the distal end side, connected to the driving portion 2, and the tubular body 8 to which the operation portion 5 is attached As shown in FIG. 3, the drive shaft 9 extending in the tube 8 is provided. In the flange portion 6, the drive shaft 9 is rotated by the drive portion 2, and the rotation of the drive shaft 9 is transmitted to the speed reduction mechanism 3 connected to the tip. And the said collar part 6 inclines below from the base end side to the front end side, and has an inclination angle of 30 degrees.

  The speed reduction mechanism 3 has three speed reduction mechanisms, a first speed reduction mechanism, a second speed reduction mechanism, and a third speed reduction mechanism in the gear case 10, and the rotational force of the drive unit 2 is used as the first speed reduction mechanism. , The direction is changed while the speed is reduced to 1 / 1.6 by the second speed reduction mechanism, and the speed is further reduced to 1/3 by the third speed reduction mechanism. Accordingly, the speed reduction mechanism 3 can reduce the rotational force of the drive unit 2 to 1 / 19.2 (about 1/20). As shown in FIG. 6, the gear case 10 is composed of two cases divided into two in the vertical direction, and the two cases are assembled so as to be detachable by bolts.

  As shown in FIGS. 3 and 4, the first reduction mechanism is provided at the tip of the drive shaft 9 in the gear case 10, and includes a pinion gear 11, an idle gear 12, and a spur gear that are three spur gears. 13 has a reduction ratio of 1/4. The pinion gear 11 is fixed to the tip of the drive shaft 9 and is rotatably held in the gear case 10 by two bearings 31 and 32 disposed in the gear case 10, and is rotated by the drive shaft 9. . The idle gear 12 is a two-stage gear that is rotatably held in the gear case 10 by a shaft 14 that passes through the center, and is engaged with the pinion gear 11 and the spur gear 13. The idle gear 12 is disposed at a predetermined position in the gear case 10 via two thrust washers 29. The spur gear 13 is located in front of the pinion gear 11, and its central axis is located on an extension line of the drive shaft 9 and the central axis of the pinion gear 11. The spur gear 13 is meshed and engaged with the shaft portion of the first pinion gear 15 so as to transmit rotation, and the shaft portion of the first pinion gear 15 is provided with two bearings 33 and 34 disposed in the gear case 10. Thus, the spur gear 13 is rotatably held in the gear case 10.

  As shown in FIGS. 3 and 4, the second reduction mechanism includes a first pinion gear 15 and a bevel gear 16, and thereby has a reduction ratio of 1 / 1.6. The shaft portion of the first pinion gear 15 is disposed so as to extend on the extension line of the central axis of the spur gear 13, and is rotated by the spur gear 13 engaged and engaged with the end portion of the shaft portion. The first pinion gear 15 has an axial angle of 30 °, and by engaging with the bevel gear 16, the direction of the central axis of rotation is changed by 30 °, and the central axis of rotation becomes the horizontal direction. The bevel gear 16 is engaged with and engaged with the shaft portion of the second pinion gear 17, and the shaft portion of the second pinion gear 17 has two bearings 35 disposed in the gear case 10 so as to sandwich the bevel gear 16. The pinion collar 21 that is rotatably held by the shaft 36 and in which the shaft portion is inserted is disposed between the bearing 36 and the bevel gear 16 so that the bevel gear 16 is rotatable in the gear case 10. Is retained.

  As shown in FIGS. 3 and 5, the third reduction mechanism includes a second pinion gear 17 and an upper bevel gear 18 that is vertically arranged with the gear shaft 20 as a central axis so as to sandwich the second pinion gear 17 from above and below. The lower bevel gear 19 has a reduction ratio of 1/3, and the center axis of rotation is changed in the vertical direction. At this time, the upper bevel gear 18 and the lower bevel gear 19 are rotated in opposite directions by the second pinion gear 17. The second pinion gear 17 has a shaft portion extending in the horizontal direction, and is rotatably held by the two bearings 35 and 36. The upper part of the gear shaft 20 is inserted into the central opening of the upper bevel gear 18, the teeth provided on the inner peripheral surface of the opening of the upper bevel gear 18, and the outer peripheral surface of the upper part of the gear shaft 20. As the teeth mesh with each other, the upper bevel gear 18 is engaged with the upper portion of the gear shaft 20, and the rotation of the upper bevel gear 18 is transmitted to the gear shaft 20.

  As shown in FIGS. 3 and 5, a bearing 37 that rotatably holds the upper end of the gear shaft 20 protruding upward from the upper bevel gear 18 is disposed above the upper bevel gear 18. A collar 22 and a snap ring 23 are disposed below the bevel gear 18. The snap ring 23 is fitted into a groove provided on the outer peripheral surface of the gear shaft 20. The collar 22 is held on the gear shaft 20. In this manner, the upper bevel gear 18 is engaged with the gear shaft 20 and is rotatably held in the gear case 10.

  As shown in FIGS. 3 and 5, the lower bevel gear 19 has a central portion of the gear shaft 20 inserted into a central opening with a predetermined gap, and the opening has a step that expands outward. The lower bevel gear 19 and the gear shaft 20 rotate smoothly and individually because the bearing 38 is disposed in the stepped portion of the opening and the gear shaft 20 is inserted into the bearing 38. The lower bevel gear 19 can be rotated in the opposite direction to the upper bevel gear 18 and the gear shaft 20 by the second pinion gear 17. The shaft portion of the lower bevel gear 19 is rotatably held by a bearing 39 disposed in the gear case 10.

  By such a speed reduction mechanism, the rotational force by the drive unit 2 is decelerated, and the direction is changed and transmitted to the upper blade 4 and the lower blade 5. The upper blade 4 is rotated by the rotation of the lower bevel gear 19 being transmitted through an upper holder 24 disposed at the lower end of the shaft portion of the lower bevel gear 19, and the lower blade 5 is rotated by the upper bevel gear 18. The rotation is transmitted through the gear shaft 20 and rotated.

  The second reduction mechanism has a reduction ratio smaller than that of the other reduction mechanisms, which is to ensure a gap between the upper blade 4 and the gear case 10. In order to increase the reduction ratio of the second reduction mechanism, it is necessary to increase the bevel gear 16, but when the bevel gear 16 increases, the distance L shown in FIG. The distance from the upper blade 4 becomes narrow, and there is a possibility that the grass may wind around this portion when the mower 1 is used. Therefore, the present invention secures the distance L of 13.5 mm by making the bevel gear 16 as small as possible. As a result, the reduction ratio of the second reduction mechanism is small.

  The upper holder 24 includes an annular flange having an opening in the center, a first cylindrical portion provided on the upper surface of the flange, and a second cylindrical portion provided in the first cylindrical portion on the upper surface of the flange. A third cylindrical portion provided on the bottom surface of the flange portion, and a fourth cylindrical portion provided in the third cylindrical portion on the lower surface of the flange portion, and on the outer side below the gear case 10 Has been placed. As shown in FIGS. 3 and 5, the lower end of the shaft portion of the lower bevel gear 19 protrudes downward from the circular opening 101 of the gear case 10 and is inserted into the opening of the upper holder 24. The teeth provided on the inner peripheral surface of the opening and the teeth provided on the outer peripheral surface of the lower portion of the shaft portion of the lower bevel gear 19 are engaged with each other, so that the rotation of the lower bevel gear 19 is transferred to the upper holder 24. Communicated.

  As shown in FIGS. 3 and 5, the first cylindrical portion of the upper holder 24 is inserted into an annular groove 102 provided on the lower surface of the gear case 10, and the upper end of the second cylindrical portion of the upper holder 24 is The upper holder 24 is disposed so as to be located in the opening 26 of the gear case 10, and the bearing 39 is disposed on the opening 101 of the gear case 10, so that the opening 101 is externally provided. The foreign matter is prevented from entering the gear case 10 through the through hole.

  The upper blade 4 is fixed to the lower surface of the collar portion of the upper holder 24 using a bolt, and the rotation of the lower bevel gear 19 is transmitted to the upper blade 4 through the upper holder 24, and the upper The blade 4 can be rotated. At this time, the third cylindrical portion of the upper holder 24 is inserted into the opening 46 of the upper blade 4.

  The lower blade 5 rotates when the rotation of the upper bevel gear 18 is transmitted through the gear shaft 20. An upper end of the gear shaft 20 is rotatably held by the bearing 37, passes through the bearing 38, and a lower portion passes through a bearing 40 disposed in the opening of the upper holder 24. A first lower holder 25 and a second lower holder 26 positioned below the upper holder 24 are attached to the lower portion of the gear shaft 20, and a cover 28 is disposed below the second lower holder 26. The first lower holder 25, the second lower holder 26, and the cover 27 are attached to the gear shaft 20 by hexagon socket head bolts 28 engaged with threaded portions of the gear shaft 20.

  The lower blade 5 is sandwiched between the first lower holder 25 and the second lower holder 26, whereby the lower blade 5 is fixed to the gear shaft 20, and the gear shaft 20 is rotated. The lower blade 5 is rotated. The first lower holder 25 is provided with an annular rib protruding upward, and the rib is inserted with a gap between the third cylindrical portion and the fourth cylindrical portion of the upper holder 24. The first lower holder 25 and the upper holder 24 are arranged so as not to interfere with each other. The lower surface of the first lower holder 25 is provided with a convex portion projecting downward, and the convex portion is inserted into the opening of the lower blade 5, and the portion projecting downward from the opening is the second lower holder. 26 is inserted into a recess on the upper surface of 26. Accordingly, the lower blade 5 is disposed at a predetermined position and is fixed by being sandwiched between the first lower holder 25 and the second lower holder 26.

  The cover 27 covers the second lower holder 26 from below, and the hexagon socket head bolt 28 screw-engaged with the gear shaft 20 is positioned in a central recess, so that the reduction mechanism Protect the bottom of the.

  The upper blade 4 is curved so that the center protrudes upward. As shown in FIG. 7A, the upper blade 4 and a plurality of pieces arranged at equal intervals on the outer periphery of the main body 41 are provided. A cutting edge 42 is provided. Twelve cutting edges 42 are provided at equal intervals. As shown in FIG. 7A, each cutting edge 42 has a substantially trapezoidal planar shape, and a part of the cutting edge 42 is bent downward. An inclined surface 44 is provided. An inclined surface 45 that is bent downward from the outer peripheral edge is also provided in a part of the outer peripheral edge of the main body 41 between the blade edges 42, and the inclined surface 45 is formed continuously with the inclined surface 44. Yes. The inclination angle of the inclined surface 44 is 30 °.

  An opening 43 is provided at the center of the upper blade 4, and four bolt holes 46 are provided around the opening 43. The upper blade 4 is positioned by inserting the third cylindrical portion of the upper holder 24 into the opening 43, and the bolt inserted into the bolt hole 46 is engaged with the upper holder 24. Thus, the upper blade 4 is fixed to the upper holder 24.

  The lower blade 5 is curved so that the center protrudes downward. As shown in FIG. 7B, the lower blade 5 is disposed at equal intervals on the outer periphery of the main body 51 and the main body 51. The cutting edge 52 is provided. As shown in FIG. 7B, the blade edge 52 has a substantially trapezoidal planar shape, and a part of the blade edge 52 is provided with an inclined surface 54 bent upward. An inclined surface 55 bent upward from the outer peripheral edge is also provided on a part of the cutting edge 52 on the outer peripheral edge of the main body 51, and the inclined surface 55 is formed continuously with the inclined surface 54. The inclination angle of the inclined surface 54 is 30 °.

  An opening 53 is provided at the center of the lower blade 5, and the lower blade 5 is positioned by inserting a convex portion on the lower surface of the first lower holder 25 into the opening 53. Then, the lower blade 5 is sandwiched between the first lower holder 25 and the second lower holder 26 disposed below the lower blade 5, so that the lower blade 5 is engaged with the gear shaft 20. It is fixed and can be rotated by the gear shaft 20.

  As shown in FIG. 3, the upper blade 4 and the lower blade 5 are superimposed on each other and pressed against each other in a state of being attached to the mowing machine 1, and the inclined surface of the upper blade 4. The lower ends of 44 and 45 are in contact with the upper ends of the inclined surfaces 54 and 55 of the lower blade 5. At this time, the bending amounts of the upper blade 4 and the lower blade 5 are both reduced, and the lower end of the inclined surface 44 of the upper blade 4 and the upper end of the inclined surface 54 of the lower blade 5 are in close contact with each other. It touches. Thereby, the mowing machine 1 increases the degree of adhesion between the upper blade 4 and the lower blade 5 during the mowing operation, and can improve the cutting force by the upper blade 4 and the lower blade 5.

  Next, the operation method of the mower 1 of the present invention will be described. When the mowing machine 1 starts the drive unit 2 by the operation unit 7, the drive shaft 9 of the collar unit 6 is rotated by the drive unit 2, and the pinion gear 11 fixed to the tip of the drive shaft 9 is The rotation of the pinion gear 11 is transmitted to the spur gear 13 via the idle gear 12, and at this time, the rotation of the drive shaft 9 is reduced to ¼. In this way, the rotation of the drive shaft 9 is reduced to ¼ by the first reduction mechanism and transmitted to the second reduction mechanism.

  As the spur gear 13 rotates, the shaft portion of the first pinion gear 15 rotates, so that the first pinion gear 15 rotates. The rotation of the first pinion gear 15 is transmitted to the bevel gear 16, but at this time, the direction of rotation is changed by 30 °. The shaft portion of the second pinion gear 17 is rotated by the rotation of the bevel gear 16, whereby the second pinion gear 17 is rotated. Thus, the rotation decelerated to 1 / 1.6 by the second reduction mechanism is transmitted to the third reduction mechanism, and the central axis of the rotation is changed in the horizontal direction.

  The rotation of the second pinion gear 17 is transmitted to the upper bevel gear 18 and the lower bevel gear 19. At this time, the upper bevel gear 18 and the lower bevel gear 19 are rotated in directions opposite to each other. Thus, the rotation reduced to 1/3 by the third reduction mechanism is transmitted to the upper bevel gear 18 and the lower bevel gear 19, and the central axis of the rotation is changed in the vertical direction. Thus, the rotation of the drive shaft is finally decelerated to 1 / 19.2 by the reduction mechanism and transmitted to the upper bevel gear 18 and the lower bevel gear 19.

  The rotation of the lower bevel gear 19 is transmitted to the upper blade 4 via the upper holder 24, whereby the upper blade 4 rotates. At the same time, the rotation of the upper bevel gear 18 in the direction opposite to the lower bevel gear 19 is rotated. Is transmitted to the lower blade 5 via the gear shaft 20 so that the lower blade 5 rotates in the opposite direction to the upper blade 4.

  In this way, the upper blade 4 and the lower blade 5 are rotated in the opposite directions by transmitting the rotational force of the driving unit 2 to 1 / 19.2 by the speed reduction mechanism. Since the cutting edges 42 and 52 of the upper blade 4 and the lower blade 5 have the inclined surfaces 44 and 54, the cutting force can be improved.

  Since the speed reduction mechanism of the mower 1 has a simple structure and is compact compared to the conventional one, the weight reduction can be realized and the workability can be improved. In particular, reducing the weight of the vicinity of the tip of the collar greatly contributes to improvement in workability.

  In the mowing machine 1, the upper blade 4 and the lower blade 5 can be easily attached and detached with bolts, so that the polishing and replacement of the upper blade 4 and the lower blade 5 can be easily performed, so that maintenance is possible. Will improve.

  As shown in FIG. 6, the gear case 10 has a vertically divided structure, which can reduce the weight and improve the maintainability.

  In the case of a conventional brush cutter using one blade, in order to cut grass while moving the brush cutter in one direction, the grass could only be cut within a range of about 1/4 of the blade. In the mower 1 of the present invention, the upper blade 4 and the lower blade 5 rotate in directions opposite to each other, so that the grass can be cut in the entire range of the blade, so that the ability to cut the grass is improved about four times. .

DESCRIPTION OF SYMBOLS 1 Mower 2 Drive part 3 Deceleration mechanism 4 Upper blade 5 Lower blade 6 Gutter part
7 Operation part 8 Tube 9 Drive shaft 10 Gear case 11 Pinion gear 12 Idle gear 13 Spur gear 14 Shaft 15 First pinion gear 16 Bevel gear 17 Second pinion gear 18 Upper bevel gear 19 Lower bevel gear 20 Gear shaft 21 Pinion collar 22 Color 23 Snap ring 24 Upper 25 First Lower Holder 26 Second Lower Holder 27 Cover 28 Hexagonal Bolt 29 Thrust Washer 41 Main Body 42 Blade Edge 43 Opening 44 Inclined Surface 45 Inclined Surface 46 Bolt Hole 51 Main Body 52 Blade Edge 53 Opening 54 Inclined Surface 55 Inclined Surface 101 Opening 102 groove

Claims (5)

A drive that generates rotational force,
An upper blade and a lower blade rotating by the rotational force,
A deceleration mechanism that decelerates the rotational force of the drive unit, transmits the rotational force to the upper blade and the lower blade, and rotates them in opposite directions;
The drive unit is provided on the proximal end side, and the speed reduction mechanism is provided on the distal end side. The drive shaft that transmits the rotational force of the drive unit to the speed reduction mechanism is provided in the tube, and is inclined downward from the proximal end side to the distal end side. Buttock, and
A mowing machine including an operation unit for operating the upper blade and the lower blade,
The speed reduction mechanism has a first speed reduction mechanism, a second speed reduction mechanism, and a third speed reduction mechanism provided in a gear case,
The first reduction mechanism has three spur gears located at the tip of the drive shaft,
The second reduction mechanism has a first pinion gear and a bevel gear, and at the same time decelerates, changes the central axis of rotation by the drive shaft in the horizontal direction,
The third reduction mechanism has a second pinion gear that is rotated by the bevel gear, and an upper bevel gear and a lower bevel gear that are arranged vertically so as to sandwich the second pinion gear from above and below with the gear shaft as a central axis. At the same time, change the center axis of rotation from horizontal to vertical,
The lower bevel gear is disposed so as to be rotatable with respect to the gear shaft, and the upper blade is connected to the lower bevel gear so as to transmit a rotational force, and the upper blade is rotated by the rotation of the lower bevel gear. The upper bevel gear rotates the gear shaft, the lower blade is attached to the lower end of the gear shaft, and the upper blade and the lower blade are rotated by the rotation of the upper bevel gear. A mowing machine that rotates in the opposite direction to the lower blade.   The reduction ratio of the first reduction mechanism is 1/4, the reduction ratio of the second reduction mechanism is 1 / 1.6, and the reduction ratio of the third reduction mechanism is 1/3. The mower according to claim 1.   The mowing machine according to claim 1 or 2, wherein an axis angle of the bevel gear is 30 °.   The mower according to any one of claims 1 to 3, wherein the gear case is vertically divided into two parts and is detachable from each other. The upper blade has a main body portion and a plurality of blade edges arranged at equal intervals on the outer periphery of the main body portion, the upper blade is curved so that the center protrudes upward, and the blade edge is downward Has an inclined surface inclined to
The lower blade has a main body portion and a plurality of blade edges arranged at equal intervals on the outer periphery of the main body portion, the lower blade is curved so that the center protrudes downward, and the blade edge is upward Has an inclined surface inclined to
The lower end of the inclined surface of the upper blade and the upper end of the inclined surface of the lower blade are brought into contact with each other when the upper blade and the lower blade are rotated. The mower described.