JP3604639B2 - Rotary cultivator - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a rotary tiller connected to a tractor.
[0002]
[Prior art]
As this kind of rotary cultivator, for example, one disclosed in Japanese Patent Application Laid-Open No. 9-121607 is known.
In this conventional rotary tilling machine, the left and right ends of the rotary tilling claw shaft are rotatably supported by bearings housed in a bearing case, and the bearing case is attached to the chain case by bearing case mounting bolts. . A stopper for preventing the bearing housed in the bearing case from coming off is attached to the chain case by welding.
[0003]
Alternatively, the bearing of the chain case may be burred to prevent the bearing from coming off.
[0004]
[Problems to be solved by the invention]
When the stopper is welded to the chain case, there is a problem that distortion of the back plate of the chain case easily causes oil leakage.
In addition, in the case of burring, restriking (processing twice) is required in order to obtain dimensional accuracy, and the cost is high.
Therefore, an object of the present invention is to provide a rotary tiller having a stopper that is low in cost and does not cause welding distortion.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, the present invention has taken the following measures. That is, it is an aspect of the present invention, mounted rotary tilling claws shaft is coupled to a drive shaft which is rotatably supported by a bearing housed in the bearing casing, the bearing case by a bearing case mounting bolts chain case The chain case includes a back plate and a front plate, a space for accommodating the chain is formed between the back plate and the front plate, and a sprocket engaging with the chain is fitted to the drive shaft. In the rotary tiller, a stopper for preventing the bearing from coming out of the bearing case into the chain case is fastened together by the bearing case mounting bolt , and a nut is welded to the stopper, and the nut is welded. And the bearing case mounting bolt is screwed into the stopper, and the stopper is On the back plate of the serial chain case lies in the fact that has been temporarily stopped by spot welding.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In FIG. 2, reference numeral 1 denotes a transmission case constituting a rear portion of the body of the tractor, on which a work implement lifting hydraulic device 3 having a pair of left and right lift arms 2 is provided. 4 are projected. A three-point link 5 is provided at the rear of the transmission case 1, and the front end side of the top link 6 of the three-point link 5 is pivotally connected to a bracket 7 fixed to the transmission case 1, and is connected to the three-point link 5. The front ends of the left and right lower links 8 are pivotally connected to the left and right sides of the rear part of the transmission case 1, and the middle of the lower links 8 in the front-rear direction is connected to the left and right lift arms 2 via lift rods 9.
[0008]
A connecting frame 11 is provided at the rear end of the three-point link 5, and a rotary tiller 12 is detachably connected via the connecting frame 11.
As shown in FIG. 3, the rotary cultivator 12 is of a side drive type. Support gears 14 are provided on both left and right sides from a gear case 13 at a central portion in the left and right direction. A chain case 15 is provided with a rotary machine frame 17 in which side frames 16 are attached and fixed to the outer end of the right support arm 14, respectively.
[0009]
In the lower part of the rotary machine frame 17, between the lower part of the chain case 15 and the side frame 16, a pawl shaft 18 rotatably supported around the left-right axis, and a plurality of pawls mounted on the pawl shaft 18 And a rotary tilling part 20 composed of a tilling claw 19 of FIG. The rotary machine casing 17 is provided with a rotary cover 21 that covers the rotary tilling unit 20.
The rotary cover 21 includes a main cover 22 that covers an upper part of the tilling unit 20, a rear cover 23 pivotally connected to a rear end of the main cover 22 so as to be rotatable around a left-right axis, and a cultivating unit 20. And a pair of left and right side covers 24 covering the rear upper portions of the left and right sides.
[0010]
As shown in FIG. 1, the chain case 15 includes a back plate 15a and a front plate 15b, and a space for accommodating the chain is formed between the back plate 15a and the front plate 15b. On the lower right side of the back plate 15a, a cylindrical bearing case 25 that penetrates the back plate 15a is mounted and fixed by bearing case mounting bolts 26. The drive shaft 28 is inserted into and supported by the bearing 27 fitted inside the bearing case 25. A flange 29 is integrally formed on the right end side of the drive shaft 28, and a flange 30 fixed to the left end side of the claw shaft 18 is fixed to the flange 29 with a bolt 31.
[0011]
A sprocket 32 is spline-fitted on the left side of the drive shaft 28 and is prevented from slipping out. The sprocket 32 receives the rotational power transmitted from the PTO shaft of the tractor to the PIC shaft of the rotary in the bevel gear transmission in the gear case 13. The transmission is performed via a mechanism, a transmission shaft in the left support arm 14, a sprocket in the upper part of the chain case 15, a chain mounted on the sprocket, and the like. It is rotationally driven to rotate in the direction (see FIG. 2).
[0012]
An oil seal 33 is internally fitted between the bearing 27 and the flange 29 of the bearing case 25, and a seal cover 34 for protecting the oil seal 33 is externally fitted to the drive shaft 28 on the left side of the flange 29. ing. A ring-shaped mounting wall 35 for mounting and fixing to the outer surface of the back plate 15a of the chain case 15 is formed integrally with the bearing case 25, and the outer periphery of the mounting wall 35 has the seal cover 34 and the drive shaft. A protective cover portion 36 is integrally formed so as to protrude so as to cover the entire outer periphery of the flange 29 of 28.
[0013]
The protective cover 36 is provided near the flange 29 so that grass, straw, and the like do not enter.
The bearing case 25 is provided with a step having a smaller diameter than the outer ring diameter of the bearing 27 to prevent the bearing 27 from moving rightward in the axial direction. The axial movement of the bearing 27 to the left in the axial direction is prevented by the stopper 37.
The stopper 37 is formed in a ring shape and is fastened to the inside of the back plate 15 a by the bearing case mounting bolt 26. The nut for co-tightening is fixed to the stopper 37 by welding or the like.
[0014]
If the stopper 37 is temporarily fixed to the back plate 15a by spot welding or the like, assembly of the bearing case 25 and the like becomes easy.
On the claw shaft 18, a claw mounting bracket 39 for mounting and fixing the tilling claw 19 is fixed by welding.
On the left and right ends of the claw shaft 18, when cultivating the field, long stalks of grass, straw, and the like in the field are caught by the cultivating claw 19 and the claw mounting bracket 39 and rotate around, and from the claw shaft 18 side. In order to prevent the stem such as grass from winding around the outer periphery of the protective cover portion 36 of the bearing case 25, a stem winding prevention device 40 (see FIG. 3) for cutting the stem is provided.
[0015]
Also, since the lower part of the chain case 15 comes into contact with the soil when tilling the field, a protector 41 is provided at the lower part of the chain case 15, and the lower part of the rear part of the protector 41 has the lower side surface and the lower surface. An extension portion 42 is provided which extends rearward from the rear surface. The extension portion 42 allows the front lower portion of the side cover 24 of the rotary cover 21 and the inner surface in the left-right direction of the lower portion of the chain case 15. The grass and the like can be prevented from being dragged by the grass and the like, and the occurrence of tilling vibration and the increase in horsepower consumption due to the grass and the like can be prevented.
[0016]
The extension portion 42 is provided so as to approach the side cover 24 from the protector 41 toward the side cover 24, thereby improving the flow of grass and the like behind the chain case 15. In addition, the same thing as the extension part 42 of the protector 41 is also mounted on the side frame 16 side.
As shown in FIG. 2, a pair of right and left bouncing devices 43 that straddle the main cover 22 and the rear cover 32 are provided above the rotary cover 21. The bouncing device 43 has a bouncing rod 44, the front end of which is pivotally attached to the support arm 14 so as to be rotatable around the left-right axis, and the rear end of which is connected to a receiving member 45 by an axial center. It is inserted so that it can freely move in the direction, and is stopped by a retaining ring. A compression coil spring 46 is fitted over the bouncing rod 44, and the rear end of the coil spring 46 contacts the receiving member 45 and the front end contacts the stopper 47.
[0017]
The receiving member 45 is supported by a bracket 48 erected on the rear surface of the rear cover 23 so as to be rotatable around the left and right axes.
As shown in FIGS. 4 and 5, an upwardly projecting projection 49 is formed on the upper portion of the receiving member 45, and a storage recess 50 orthogonal to the elastic rod 44 is formed from below. A lock pin 51 and a first spring 52 for urging the lock pin 51 toward the lower rod 44 are incorporated above the lower rod 44 of the storage recess 50.
[0018]
The lock pin 51 includes a lower head 53 and an upper shaft 54. The head 53 is formed in a cylindrical shape having an inclined guide surface 55 on the lower front side. The upper part can be inserted into and removed from an engagement hole 56 formed at an appropriate interval in the axial direction.
The shaft portion 54 of the lock pin 51 protrudes upward from the protruding portion 49. A flat washer 58 is provided at the upper end of the protruding portion and is prevented from falling off by a spring pin 57. A second spring 59 is interposed between the lower surface of the protrusion 58 and the upper surface of the protrusion 49.
[0019]
The second spring 59 is stronger than the first spring 52. Accordingly, the lock pin 51 is moved upward by the second spring 59, and the engagement of the rod 44 with the engagement hole 56 is released.
A pair of left and right brackets 60 are provided on the upper part of the receiving member 45, and an operation lever 62 is mounted between the brackets 60 via a support shaft 61 so as to be rotatable in the front-rear direction.
The operation lever 62 is formed in an L-shape when viewed from the side, and formed in a U-shaped cross section from the left and right side walls 63 and the connecting wall 64, and the edges of the left and right side walls 63 are formed on the upper surface of the flat washer 58. Abut. The contact portion of the operation lever 62 includes a first contact surface 65 and a second contact surface 66 that are orthogonal to each other. The first contact surface 65 is located farther from the support shaft 61, and The contact surface 66 is located near the support shaft 61. The side opposite to the contact surface via the support shaft 61 is an operation unit 67 that can be gripped by hand.
[0020]
As shown in FIG. 4, when the operation portion 67 of the operation lever 62 is lowered, the first contact surface 65 presses the flat washer 58, the second spring 59 contracts, the first spring 52 expands, and the lock pin 51 descends. When the rear cover 23 is raised, the lock is automatically performed.
When the operating lever 62 is raised, the second contact surface 66 comes into contact with the flat washer 58, the second spring 59 expands, the first spring 52 contracts, and the lock pin 51 tries to move up. The lock pin 51 and the rod 44 are kept locked by the weight of the cover 23. Therefore, when the rear cover 23 is slightly lifted, the locked state between the lock pin 51 and the engagement hole 56 is released, the lock pin 51 is raised, and the rear cover 23 can be freely moved.
[0021]
As described above, even when the operation lever 62 is operated with the second spring 59 interposed between the operation lever 62 and the lock pin 51, the lock pin 51 does not directly move and the thrust load of the lock pin 51 is removed. Then, since the lock pin 51 is moved, the lock of the lock pin 51 is automatically released.
The one shown in FIG. 6 is such that the rotation speed of the rotary cultivator can be set arbitrarily regardless of the engine rotation speed of the tractor. That is, in the power transmission from the PTO shaft 4 of the tractor shown in FIG. 2 to the rotary tiller via the universal joint, the rotation speed of the claw shaft 18 is determined by the rotation speed of the PTO shaft 4. Therefore, the number of rotations of the claw shaft 18 can be set arbitrarily as shown in FIG.
[0022]
That is, a hydraulic pump 68 is provided on the tractor side, a hydraulic motor 69 is provided on the rotary tiller 12 side, and both are connected by a hydraulic hose 70.
As the hydraulic pump 68, a variable displacement pump is used. The hydraulic pump 68 is attached so as to obtain power from the PTO shaft 4. The output shaft of the hydraulic motor 69 is connected to the input shaft of the gear case 13.
By making the flow rate of the hydraulic pump 68 variable, the rotation speed of the claw shaft 18 can be arbitrarily changed. Further, since the tractor and the rotary cultivator 12 are connected by the hydraulic hose 70, the degree of freedom of the attitude of the rotary cultivator 12 with respect to the tractor is higher than that of the conventional rotator connected with a universal joint.
[0023]
In FIG. 7, the output shaft of the hydraulic motor 69 is arranged so as to be parallel to the axial direction of the claw shaft 18, and is directly connected to the upper sprocket of the chain case 15.
Note that the present invention is not limited to the embodiments described above.
[0024]
【The invention's effect】
According to the present invention, a feature of the present invention is that a rotary tilling claw shaft is coupled to a drive shaft rotatably supported by a bearing housed in a bearing case, and the bearing case is attached to a chain case by a bearing case. The chain case is composed of a back plate and a front plate, a space for accommodating the chain is formed between the back plate and the front plate, and a sprocket engaging with the chain is attached to the drive shaft. In the fitted rotary tiller, a stopper for preventing the bearing from coming out of the bearing case into the chain case is jointly fastened by the bearing case mounting bolt, so that compared to a conventional welding structure, The distortion of the chain case does not occur, and oil leakage is prevented.
Further, the stopper nut is welded together with the to the nut bearing case mounting bolt is screwed, said stopper, because it is temporarily fixed by spot welding to the back plate of the chain case, bearing case and the like Is easy to assemble.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a chain case showing an embodiment of the present invention.
FIG. 2 is a side view showing the entire configuration of the rotary tiller.
FIG. 3 is a rear view of the rotary tiller.
FIG. 4 is a side sectional view of a main part of the bouncing device.
FIG. 5 is a front sectional view of a main part of the bouncing device.
FIG. 6 is a power transmission configuration diagram of a rotary tiller using a hydraulic pump and a hydraulic motor.
FIG. 7 is a rear view of a rotary tiller using a hydraulic motor.
[Explanation of symbols]
12 Rotary tiller 15 Chain case 18 Claw shaft 25 Bearing case 26 Bearing case mounting bolt 27 Bearing 37 Stopper 38 Nut

Claims (1)

Rotary tilling claws shaft is coupled to freely supported drive shaft rotation by a bearing housed in the bearing casing, the bearing case is attached by a bearing case mounting bolts to the chain case, the chain case and back plate In the rotary tiller, comprising a front plate, a space for accommodating a chain is formed between the back plate and the front plate, and a sprocket engaged with the chain is fitted to the drive shaft .
A stopper for preventing the bearing from coming out of the bearing case into the chain case is fastened together by the bearing case mounting bolt,
The stopper nut is welded together with the to the nut bearing case mounting bolt is screwed, said stopper, rotary tilling, characterized in that it is temporarily fixed by spot welding to the back plate of the chain case Machine.

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