JPH0238565Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a tilling claw for both forward and reverse rotation in a forward and reverse rotary rotary, and the soil reaction force applied to the tilling claw is strengthened by the claw shaft by bringing the tilling claw into surface contact with the claw shaft. The purpose is to support the

There are two types of rotary tillage methods: the up-cut method and the down-cut method, and the so-called forward-reverse rotary method, which uses both methods as appropriate depending on the type of crops planted or field conditions, has already been proposed in Publication of Utility Model Publication No. 41-1925. ing. Kono Jiko Showa 41-1925
In the rotary disclosed in the publication, the mounting base of the tilling claw, which has blades on the front and rear edges in the rotation direction, is fixed to the claw mounting bracket of the claw shaft that can be rotated in the forward and reverse directions with bolts, etc., so that the claw shaft can be rotated in the forward or reverse direction. As a result, a common tiller can be used for both up-cutting and down-cutting.

However, the conventional claw mount is formed in a box shape, and is easily deformed because it is installed with the mounting base of the tilling claw inserted, and all of the soil reaction force of the tilling claw is received by the claw mount. There are problems.

In order to solve this problem, it is conceivable to form the claw attachment body with a flat plate, and make the tilling claws contact the claw shafts so that part of the soil reaction force is received by the claw shafts. However, in this configuration, if the tilling claws and the claw shaft are in line or point contact, there is a risk of deformation of one or the other, and
The problem arises that the best driving angle cannot be obtained due to the deformation.

The present invention solves these problems, and its features include a claw shaft that can be switched between forward and reverse directions, supported swingably in the rotational direction via a claw mount, and In a tilling claw having a blade portion, a pair of arcuate contact surfaces are formed on the proximal edge of the tilling claw on the claw shaft side, which come into surface contact with the claw shaft during forward and reverse rotation, respectively.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the overall configuration of a forward/reverse rotary tiller 1. This rotary tiller 1 is mainly composed of a machine frame 2, a tiller section 3, a tiller cover device 4, and the like. It is mounted so that it can be raised and lowered via a point linkage mechanism.

The machine frame 2 includes support arms 6 protruding from the left and right sides of a gear case 5 incorporating a forward/reverse gear transmission mechanism, and a transmission case 7 and a side frame 18 fixed to the outer end of each support arm 6. ing. 8 is an input shaft protruding forward from the gear case 5; 9 is a transmission shaft that transmits the power of the input shaft 8 to the transmission case 7; 10 is a support frame extending rearward from the machine frame 2; It supports a gauge wheel 11, and its angle can be freely adjusted by a height adjustment mechanism 12.

The tillage cover device 4 includes a main cover 13 fixed to the machine frame 2, a rear cover 14 pivoted to the rear end of the main cover 13, and a pair of left and right side covers 15. is the average pressure adjustment mechanism 1
It is suspended by 6. Also, main cover 1
A comb-like Reiki 17 is attached to the rear end of the rear cover 3 so as to be adjustable in angle, and is located between the rear cover 14 and the tilling part 3 to prepare the tilled soil into a fine surface layer and a sub-layer soil clod.

The tilling section 3 includes a claw shaft 20 rotatably supported by the transmission case 7 and the side frame 18 about a horizontal axis, and a claw mounting body 21 fixed to the claw shaft 20.
The tiller shaft 20 has a large number of tilling claws 22 attached through the gear case 5, and the claw shaft 20 can be freely switched between forward and reverse directions by power from the gear case 5.

As shown in FIGS. 1 to 3 and 6 to 9, the tilling claws 22 are bent into a substantially rectangular shape when viewed from the side.
The mounting base 23 inserted into the claw mounting body 21 and the blade part 24 are formed into a flat plate shape, and are bent from the tip of the blade part 24 to form a scooping part 25. The front and rear edges of the portion 25 are formed with blade portions 26a and 26b that are arcuate in side view, and the blade portion 24 has a substantially circular or egg-shaped opening 27 formed in the center for soil removal.

The tilling claws 22 have a substantially round shape when viewed from the front, but are asymmetrical in the front and rear, and the blade portion 26a has a smaller curvature than the blade portion 26b, and is used for down-cut cultivation.
A mounting hole 31 is formed in the mounting base 23, through which a support shaft 30 for pivotally supporting the claw mounting body 21 passes, and a base edge 32 on the claw shaft 20 side has an outer circumferential surface of the claw shaft in the front and back. A concave abutment surface 33 having substantially the same curvature is formed. The contact surface 33a is the tiller claw 2
2 is in the normal rotation working posture A (down cut tilling shown by the imaginary line in FIG. 2), the contact surface 33b is the tiller claw 22
When in the reverse working position B (hot plowing shown by the solid line in FIG. 2), the respective working positions are maintained by coming into surface contact with the outer circumferential surface of the claw shaft 20.

The claw shaft 20 that the contact surfaces 33a and 33b contact
An arc-shaped reinforcing plate may be fixed to the outer peripheral surface of the member.

The pawl attachment body 21 includes a pair of pawl support plates 35a, 3 welded to the outer periphery of the pawl shaft 13 so as to protrude radially outward.
5b, each claw support plate 35 is approximately elliptical when viewed in the axial direction, and can support two tilling claws 22 at symmetrical positions. Both claw support plates 35 face each other with a gap, and have inner and outer peripheral edges. It is bent laterally and acts as a reinforcing rib.

The support shaft 30 has a shaft portion 36 in the center, a male screw portion 37 with a smaller diameter than the shaft portion 36 on one end, and a flange portion 38 with a larger diameter on the other end. Mounting hole 31 for plate 35a and tilling claw 22
The stepped portion 39 extends through the other claw support plate 35b.
A nut 40 is screwed into the male threaded portion 37 that abuts on the other claw support plate 35b and passes through the other claw support plate 35b, thereby fixing the support shaft 30 to the claw support plate 35b.

41 is a washer with a tongue, and 42 is a set of two disc spring claw pressing members, both of which are fitted onto the shaft portion 36 and are interposed between the tilling claw 22 and the flange portion 38. The tilling claws 22 are swingable around the support shaft 30 in the direction of rotation of the claw shaft, and the claw pressing member 42 presses the tilling claws 22 against the other claw support plate 35b, providing frictional resistance to the swinging. . This frictional resistance is
This is the soil reaction force when the tilling claws 22 in one working posture are reversed and driven into the soil, which is greater than the force that causes the tilling claws 22 to swing from each working position A or B to the neutral position due to centrifugal force. is set smaller than.
The tongued washer 41 is for avoiding sliding contact between the swinging tilling claw 22 and the claw pressure member 42.

The inner surface of the flange portion 38 of the support shaft 30 is in contact with the outer surface of one claw support plate 35a, and an annular projection 44 is formed on the inner surface. This annular projection 44 is connected to the claw pressing member 42 and the tongue washer 4.
The amount of protrusion that surrounds the claw support plate 35a is approximately the same as the wall thickness of one of the claw support plates 35a, and a cutout 45 is formed at one location, and a pair of rotation stopper projections 46 are formed on both sides of the cutout 45.

A hole 47 into which the annular projection 44 fits is formed in one of the claw support plates 35a. A notch 48 is formed at one location of the hole 47, with which a pair of rotation preventing protrusions 46 engage. The support shaft 30 is supported by an annular projection 44 relative to the claw support plate 35a and is prevented from rotating. Furthermore, a tongue piece 49 of the tongue washer 41 is engaged with the notch 45 of the annular projection 44 to prevent the support shaft 30 from rotating.

According to the present invention described in detail above, the proximal edge 32 of the tilling claw 22 is formed with a pair of arcuate contact surfaces 33a and 33b that come into surface contact with the claw shaft 20 during forward and reverse rotation. The soil reaction force applied to the tilling claws 22 is supported by the claw shafts 22 that are in surface contact with the contact surface 33, and the surface pressure is smaller than in the case of line or point contact, and the deformation of the claw shafts 20 or the tilling claws 22 is prevented. An accurate driving angle can always be obtained.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; the first is a cross-sectional side view showing the entire forward/reverse rotary, the second is a front view of the tilling claw, the third is a cross-sectional side view of the tilling claw, and the fourth is a cross-sectional side view of the tilling claw. Enlarged sectional view showing the tilling claw attachment structure, No. 5
6 is a rear view of the tilling claw, FIG. 7 is a side view, and FIGS. 8 and 9 are a plan view and a bottom view of the tilling claw, respectively. 1... Rotary machine frame, 20... Claw shaft, 21...
Claw mounting body, 22... Cultivating claw, 23... Mounting base, 24... Blade portion, 25... Scooping portion, 26...
Blade portion, 30...Support shaft, 31...Mounting hole, 32...
...Proximal edge, 33...Abutment surface, A...Forward rotation working posture, B...Reverse rotation working posture.

Claims (1)

[Scope of utility model registration request] In a tilling claw that is swingably supported in the rotational direction via a claw attachment body 21 on a claw shaft 20 that can be switched between forward and reverse directions, and has blade portions 26a and 26b on the front and rear edges,
The base end edge 32 of the tilling claw on the claw shaft 20 side has a pair of arcuate contact surfaces 3 that come into surface contact with the claw shaft 20 during forward and reverse rotation, respectively.
3a and 33b are formed.