JP2008161145A - Rotary tilling apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotary tilling apparatus capable of regulating backlashes of reverse transmission. <P>SOLUTION: The rotation of a sprocket 12 is directly transmitted to a rotary shaft 20 and further transmitted through the reversal transmission 10 to a rotary pipe 18. The backlash between a first bevel gear 14 and a pinion gear 15 is regulated, by arranging a first shim 27 between the first bevel gear 14 and a first ball bearing 13 positioned in the shaft direction relatively to the transmission case 11. The backlash between a second bevel gear 16 and the pinion gear 15 is regulated by arranging a second shim 28 in between a C-ring 31 positioned relative to the transmission case 11 and a second ball bearing 22. As a result, even when external force in the shaft direction is applied to the rotary shaft 20, the backlash of the reversal transmission 10 can be prevented from going out of order. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a rotary tiller including a tilling shaft that protrudes laterally from a transmission case. Specifically, the rotation of a rotating member in the transmission case is directly transmitted to a first tilling shaft and via a reverse transmission. The present invention relates to a rotary tiller that is configured to transmit rotation in the direction opposite to that of the first tillage shaft to the second tillage shaft.

  Conventionally, in a rotary tiller, a rotary shaft (first tillage shaft) arranged so as to protrude sideways from a transmission case and a sleeve shape are formed so as to surround the outer peripheral side of the rotary shaft. A drive pipe bevel gear (first bevel gear) that is connected to the rotary shaft so as to rotate integrally therewith, and a rotary pipe that includes a rotary pipe (second tillage shaft) disposed so as to be rotatable relative to the shaft. And a driven bevel gear (second bevel gear) that is integrally connected to the rotary shaft, and a pinion gear (third bevel gear) that is arranged to mesh with the drive and driven bevel gears so that the rotary shaft rotates in the reverse direction. The thing comprised so that it may transmit to a pipe is proposed (refer patent document 1).

Japanese Patent Laid-Open No. 2003-61401

  As shown in FIG. 4, such a rotary tiller is supported by a transmission case 111 via a bearing (first support means) 113 and by spline engagement with a rotary shaft 120. A bevel gear 114 disposed so as to rotate integrally with the rotary shaft 120; a bevel gear 116 supported by the transmission case 111 via a bearing (second support means) 121 and coupled to the rotary pipe 118; And a reverse transmission device having a bevel gear 114 and a pinion gear 115 meshing with the bevel gear 116 while being supported by the transmission case 111.

  In the reverse transmission device, the bevel gear 114 is positioned in the axial direction with respect to the rotary shaft 120 when gear meshing position adjustment, that is, backlash adjustment, is performed with respect to the pinion gear 115 meshing with the bevel gear 114. This is done by interposing a shim 127 between the sprocket 112 and the bearing 113.

  For this reason, depending on the thickness (number of sheets) of shims arranged between the sprocket 112 and the bearing 113, there may be a gap in the axial direction between the transmission case 111 and the bearing 113, as shown in part G. is there. At this time, when an axial external force is applied to the rotary shaft 120, the sprocket 112 presses the bearing 113 by the amount of the gap, and the bevel gear 114 moves in the axial direction accordingly. Then, the bevel gear 114 and the pinion 115 approach each other, and there is a possibility that abnormal noise or abnormal wear may occur due to the reduction of backlash. In addition, since the reverse transmission device is configured substantially symmetrically with respect to the sprocket 112, when the bevel gear 114 approaches the pinion gear 115 as described above, the bevel gear disposed on the opposite side is meshed. There is also a possibility that the gears move away from the pinion gear and the gears are disengaged.

  Accordingly, an object of the present invention is to provide a rotary tiller capable of adjusting the backlash of the reverse transmission and thus solving the above-mentioned problems.

The present invention according to claim 1 includes a first tilling shaft (20) and a second tilling shaft (18) projecting laterally from the transmission case (11), and the rotation within the transmission case (11). A rotary tiller (6) which transmits the rotation of the member (12) directly to the first tillage shaft (20) and to the second tillage shaft (18) via the reverse transmission (10). In
The reverse transmission device (10) includes a first bevel gear (14) supported by the transmission case (11) via first support means (13) and connected to the first tillage shaft (20). ), A second bevel gear (16) supported by the transmission case (11) via second support means (22) and connected to the second tillage shaft (18), and the transmission case A third bevel gear (15) supported by (11) and meshing with the first and second bevel gears (14, 16),
The first support means (13) is interposed in the transmission case (11) with a first gap adjusting member (27) for adjusting the gap between the first bevel gear (14) and the axial direction. Supported by restricting movement,
The second support means (22) is disposed in the axial direction with a second gap adjusting member (28) for adjusting a gap between the second case (11) and the second bevel gear (16). Supported by restricting movement,
Adjusting the backlash of the reverse transmission device (10) by the first gap adjusting member (27) and the second gap adjusting member (28);
The rotary tiller (6) is characterized in that.

  In addition, although the code | symbol in the said parenthesis is for contrast with drawing, this is for convenience for making an understanding of invention easy, and has no influence on the structure of a claim. It is not a thing.

  According to the first aspect of the present invention, the movement of the first support means is restricted in the axial direction by interposing the first gap adjusting member for adjusting the gap between the first bevel gear and the transmission case. Since the second support means is supported by the transmission case with the movement in the axial direction being restricted via the second gap adjusting member for adjusting the gap between the second bevel gear and the transmission case. The backlash between the first bevel gear and the third bevel gear is adjusted by the first gap adjustment member, and the backlash between the second bevel gear and the third bevel gear is adjusted by the second gap adjustment member. For example, even when an external force in the axial direction is applied to the first tillage shaft, the backlash is properly maintained, and abnormal noise, abnormal wear, and gear disengagement due to the backlash being out of order can be prevented. To prevent It can be. Thereby, the durability of the rotary tiller can be improved.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 3.

  As shown in FIG. 1, a cultivator 1 to which the present invention is applied includes a transmission case 2 constituting an airframe frame, an engine 3 disposed in a front portion of the airframe, and a wheel 5 disposed on a lower side of the transmission case 2. A handle 7 arranged to extend obliquely upward from the upper side of the transmission case 2 to the rear side; a transmission lever 42 arranged to extend from the upper part of the transmission case 2 along the upper side of the handle 7; A rotary tilling device 6 disposed in the lower rear portion of the case 2 and a rotary tilling depth regulating device 8 and the like are provided at a rear portion of the rotary tilling device 6.

  A belt is wound from an output pulley (not shown) of the engine 3 to a transmission pulley (not shown) fixed to an input shaft (not shown) of the transmission case 2. The pulley is covered with a case 41. In the cultivator 1 shown in FIG. 1, the direction in which the operator faces during operation, that is, the left side is generally described as the front.

  The transmission case 2 is composed of a two-piece case including a traveling chain case 2a and a tilling chain case 2b (see FIG. 2), and the traveling chain case 2a is connected to the axle 5a. The tilling chain case 2 b is connected to the rotary tilling device 6.

  As shown in FIG. 2, the rotary tiller 6 covers a transmission case 11, a rotary shaft (first tillage shaft) 20 protruding from the transmission case 11, and an outer peripheral portion of the rotary shaft 20. And a rotary pipe (second tillage shaft) 18 disposed on the surface. The rotary tiller 6 is provided with a pair of left and right reverse transmissions 10 and 10 in the transmission case 11 in order to transmit the rotation in the reverse direction to the rotary pipe 18 with respect to the rotation of the rotary shaft 20. It has been. Each of the reverse transmissions 10 and 10 is constituted by three bevel gears. The rotary tiller 6 including the reverse transmission device 10 is bilaterally symmetric, and only one will be described below.

  The transmission case 11 has a boss portion 11A that supports a first bevel gear 14 (to be described later) via a first ball bearing (first support means) 13, and an axis that is inclined at a predetermined angle with respect to the rotary shaft 20. In addition to being formed in a sleeve shape, it includes an inclined portion 11B that supports a second bevel gear 16 and a pinion gear (third bevel gear) 15 to be described later. The inclined portion 11B further includes an inner inclined portion 11a and an outer inclined portion. Part 11b, and is configured to rotatably support the rotary shaft 20. The transmission case 11 is fixed to the tilling chain case 2b by bolts 51 and nuts 52.

  The rotary shaft 20 is disposed so as to protrude from the transmission case 11 in the left-right direction substantially orthogonal to the advancing direction of the machine body, and is rotatably supported with respect to the transmission case 11 as described above. Is a shaft-like member in which splines 20s are formed. Further, the rotary shaft 20 is spline-engaged in the central portion and is connected to the sprocket (rotating member) 12 positioned in the axial direction by the C-rings 29 and 29 so as not to rotate relative to the sprocket 12. The rotation from the transmission is transmitted to the rotary shaft 20 by a chain 50 wound around a sprocket (not shown) disposed on an output shaft (not shown) of the transmission case 2. Has been. Further, a boss 23 is disposed on the outer peripheral surface of the outer side of the rotary shaft 20 so as to fit the rotary shaft 20, and a tilling claw 47 is fixed to the boss 23 via a bracket 48 with a bolt. . Further, an oil seal 38 is disposed between the transmission case 11 and the outside of the spline 20 s of the rotary shaft 20.

  The rotary pipe 18 is constituted by a sleeve shaft 18 a and a flange portion 18 b formed in a cylindrical shape, and is arranged so as to surround an outer peripheral portion at the center side of the rotary shaft 20, and rotates with respect to the transmission case 11. It is supported freely. Specifically, the outer race of the ball bearing 21 is in contact with the inner peripheral surface of the sleeve shaft 18a, and is rotatably supported by the outer inclined portion 11b of the transmission case 11 via the ball bearing 21. Yes.

  Further, a flange portion 18 b is fixed to the inner peripheral surface of the sleeve shaft 18 a by a plurality of bolts 25 outside the ball bearing 21. The inner diameter of the sleeve shaft 18a and the outer diameter of the flange portion 18b are set so as to have a predetermined gap. When the sleeve shaft 18a is not fixed by the bolt 25, the flange portion 18b is the inner peripheral surface of the sleeve shaft 18a. A spline 18 s is formed on the inner peripheral surface of the flange portion 18 b that loosely fits in a loosely engaged state, and is in spline engagement with a second bevel gear 16 described later. Further, the portion between the inner peripheral surface of the sleeve shaft 18a and the outer peripheral surface of the outer inclined portion 11b of the transmission case 11 is sealed at a portion closer to the center than the portion with which the ball bearing 21 is in contact with the sleeve shaft 18a. An oil seal 35 is disposed, and an inner peripheral surface of the flange portion 18b and an inner portion of the transmission case 11 are disposed outside a portion where the flange portion 18b and the second bevel gear 16 are spline-engaged. An oil seal 36 that seals between the inclined portion 11a and the outer peripheral surface is disposed. And the cover 37 for preventing intrusion of mud etc. is arrange | positioned in the outer edge part of this inner inclination part 11a and the flange part 18b. A plurality of brackets 46 are erected on the outer peripheral surface of the sleeve shaft 18a, and a tilling claw 45 is fixed to the brackets 46 with bolts.

  On the other hand, in the ball bearing 21, the outer race has a contact portion formed on the inner peripheral surface of the sleeve shaft 18 a with respect to the sleeve shaft 18 a of the rotary pipe 18, and a flange portion 18 b fixed by the bolt 25. The inner race is positioned in the axial direction of the rotary pipe 18 and the outer race 11b of the transmission case 11 is fitted into a groove 11d formed on the outer peripheral surface of the outer slope 11b. It is positioned in the axial direction of the rotary pipe 18 by the ring 33 and the C ring 32 fitted in the groove 11e formed on the outer peripheral surface.

  The reverse transmission device 10 is constituted by three bevel gears including a first bevel gear 14, a pinion gear 15, and a second bevel gear 16. The first bevel gear 14 includes a gear portion 14a having a gear and a cylindrical portion 14b. A spline 14s is formed on the inner peripheral surface of the cylindrical portion 14b and formed on the outer peripheral surface of the rotary shaft 20. By being spline-engaged with the spline 20s thus formed, it is configured to rotate integrally with the rotary shaft 20. Further, the first bevel gear 14 is in contact with the inner race of the first ball bearing 13 on the outer peripheral surface of the cylindrical portion 14 b, and the boss portion of the transmission case 11 via the first ball bearing 13. It is supported rotatably with respect to 11A. Thereby, the rotary shaft 20 is rotatably supported with respect to the boss portion 11 </ b> A via the first bevel gear 14 and the first ball bearing 13.

  On the other hand, in the first ball bearing 13, the outer race is fitted into a contact portion 11g formed on the inner peripheral surface of the boss portion 11A and a groove portion 11c formed on the inner peripheral surface of the boss portion 11A. The ring 26 is positioned in the axial direction, and the inner race is restricted from moving in the axial direction toward the center by contacting the sprocket 12. Then, the first shim (first gap adjusting member) 27 is disposed between the gear portion 14 a of the first bevel gear 14 and the inner race of the first ball bearing 13, whereby the first shim According to the thickness and the number of the 27, the meshing position of the first bevel gear 14 and the pinion gear 15, that is, the backlash can be adjusted.

  The second bevel gear 16 is composed of a gear portion 16a having a gear and a cylindrical portion 16b. An outer surface of a second ball bearing (second support means) 22 is formed on the inner peripheral surface of the cylindrical portion 16b. The race is abutted and is supported rotatably with respect to the inner inclined portion 11 a of the transmission case 11 via the second ball bearing 22. The second bevel gear 16 has a spline 16s formed on the outer peripheral surface of the cylindrical portion 16b. As described above, the spline engagement with the spline 18s formed on the inner peripheral surface of the flange portion 18b of the rotary pipe 18 is performed. By doing so, it is configured to rotate integrally with the rotary pipe 18.

  A pinion gear 15 meshing with each of the first bevel gear 14 and the second bevel gear 16 is rotatably supported by a pinion shaft 15A fixed to the transmission case 11, as shown in FIG. The rotation transmitted to the rotary shaft 20 is configured to be transmitted to the rotary pipe 18 in the reverse direction. In FIG. 2, the pinion gear 15 is disposed on the front side of the drawing, and is indicated by a one-dot chain line. Further, the pinion gear 15 is actually arranged at a position 180 degrees away from the rotary shaft 20, that is, at the back side of the drawing, and two are arranged on the diameter.

  On the other hand, the second ball bearing 22 contacts the gear portion 16a of the second bevel gear 16 in the outer race, and the outer periphery of the inner inclined portion 11a with respect to the inner inclined portion 11a of the transmission case 11 in the inner race. The movement of the rotary pipe 18 to the outside in the axial direction is restricted by the C ring 31 fitted in the groove 11f formed on the surface. Then, by disposing a second shim (second gap adjusting member) 28 between the inner inclined portion 11a of the transmission case 11 and the inner race of the second ball bearing 22, the second shim 28 Depending on the thickness and the number of sheets, the meshing position between the second bevel gear 16 and the pinion gear 15, that is, the backlash can be adjusted.

  Next, the operation of the rotary tiller 6 will be described.

  The rotation of the engine 3 is transmitted to the input shaft in the transmission case 2 via the belt in the case 41. Then, based on the operation of the shift lever 42 by the operator, for example, a low-speed rotation suitable for work is transmitted to the wheel 5 and, in the transmission case, the normal output rotation is transmitted to the output shaft. The forward rotation transmitted to the sprocket 12 via the chain 50 and transmitted to the sprocket 12 is transmitted to the rotary shaft 20. Then, the forward rotation transmitted to the rotary shaft 20 rotates the tillage pawl 47 in a predetermined direction (for example, the same direction as the wheels).

  On the other hand, the rotation of the sprocket 12 is transmitted to the first bevel gear 14 of the reverse transmission 10 via the rotary shaft 20 and further to the second bevel gear 16 via the pinion gear 15 supported by the transmission case 11. Transmitted as reverse rotation. The reverse rotation transmitted to the second bevel gear 16 is transmitted to the rotary pipe 18 through the spline 16s. Then, the reverse rotation transmitted to the rotary pipe 18 rotates the tillage claw 45 in the direction opposite to the predetermined direction (for example, the direction opposite to the wheel).

  The rotary pipe 18 has an axis inclined at a predetermined angle by being supported by the inclined portion 11B, so that the tilling claw 45 (see FIG. 2) reaches the lower part on the center side of the transmission case 11. It is configured. That is, the cultivator 1 can cultivate without leaving the space (the length of the rotary shaft 20).

  At this time, even when an axial external force is applied to the rotary shaft 20 as described above, the gap between the boss portion 11A of the transmission case 11 and the outer race of the first ball bearing 13 is as described above. According to the configuration, a gap is not generated, and for example, even if the sprocket 12 presses the first ball bearing 13, a force can be received by the boss portion 11A. Thereby, even if external force is added with respect to the rotary shaft 20, the 1st bevel gear 14 can prevent that this 1st bevel gear 14 is pressed, and it can prevent that backlash goes wrong.

  Further, the second bevel gear 16 has a shaft of the rotary pipe 18 with respect to the inner inclined portion 11a of the transmission case 11 by the C ring 31, the second bearing 22, and the second shim 28 disposed therebetween. Since it is positioned in the direction (backlash adjustment), even if an external force is applied to the rotary shaft 20, it is not affected and the backlash does not go wrong. Further, even when an external force is applied to the rotary pipe 18 in the axial direction of the rotary pipe 18, the flange portion 18b and the second bevel gear 16 are spline-engaged, and backlash is distorted. This can be prevented.

  Further, since the first shim 27 is disposed between the gear portion 14a of the first bevel gear 14 and the inner race of the first ball bearing 13, and the backlash can be adjusted, the sprocket 12 and the first Before the assembly with the ball bearing 13, the backlash between the first bevel gear 14 and the pinion gear 15 can be adjusted and confirmed.

  As described above, according to the rotary tiller 6 according to the present invention, the first ball bearing 13 includes the first shim 27 that adjusts the clearance between the first bevel gear 14 and the transmission case 11. The second ball bearing 22 is supported while being restricted in axial movement, and the second ball bearing 22 is moved in the axial direction via a second shim 28 that adjusts the clearance between the second bevel gear 16 and the transmission case 11. The backlash between the first bevel gear 14 and the pinion gear 15 is adjusted by the first shim 27, and the backlash between the second bevel gear 16 and the pinion gear 15 is adjusted by the second shim 28. For example, even when an axial external force is applied to the rotary shaft 20, the backlash is properly maintained and the backlash is It is possible to prevent the occurrence or abnormal wear and gear out of noise that particular originating. Thereby, the durability of the rotary tiller 6 can be improved.

  In the present embodiment, the second shim 28 is arranged between the C ring 31 and the inner race of the second ball bearing 22 so as to adjust the backlash of the second bevel gear 16. As described above, even if the backlash of the second bevel gear 16 is adjusted by arranging it between the outer race of the second ball bearing 22 and the gear portion 16a of the second bevel gear 16, the present invention. Can be applied.

The side view which shows the cultivator which concerns on this invention. The expanded sectional view which shows a rotary tillage apparatus. AA sectional drawing of FIG. The expanded sectional view which shows the conventional rotary tillage apparatus.

Explanation of symbols

6 Rotary tillage device 10 Reverse transmission device 11 Transmission case 12 Rotating member (sprocket)
13 First support means (first ball bearing)
14 1st bevel gear 15 3rd bevel gear (pinion gear)
16 Second bevel gear 18 Second tillage shaft (rotary pipe)
20 First tillage shaft (rotary shaft)
22 Second support means (second ball bearing)
27 First gap adjusting member (first shim)
28 Second gap adjusting member (second shim)

Claims (1)

A first tillage shaft and a second tillage shaft projecting laterally from the transmission case are provided, and the rotation of the rotating member in the transmission case is directly transmitted to the first tillage shaft and via a reverse transmission device. In the rotary tilling device that is transmitted to the second tillage shaft,
The reverse transmission device includes a first bevel gear supported by the transmission case via first support means and coupled to the first tillage shaft, and the transmission case via second support means. A second bevel gear supported and coupled to the second tillage shaft; and a third bevel gear supported by the transmission case and meshed with the first and second bevel gears;
The first support means is supported by the transmission case by restricting movement in the axial direction through a first gap adjusting member that adjusts a gap between the first bevel gear and the first bevel gear.
The second support means is supported by the transmission case by restricting movement in the axial direction through a second gap adjusting member for adjusting a gap between the second bevel gear and the second bevel gear;
Adjusting the backlash of the reverse transmission device by the first gap adjusting member and the second gap adjusting member;
A rotary tiller characterized by that.

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