JPH053B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a rotational drive mechanism of tilling shafts that intersect while maintaining a constant gearing angle.

<Prior art and its problems> In general, the input shaft, which is transmission-coupled with the tractor's PTO shaft, protrudes from the upper end of a center drive case that is towed by a tractor, while the input shaft also extends from the lower end of the drive case. A pair of left and right tilling axes are horizontally projected in a horizontally extending V-shaped arrangement with non-perpendicular gearing angles, and a plurality of disc plows are arranged in parallel on both tilling axes. For example, the tilling machine proposed by the present applicant is disclosed in Japanese Patent Application Laid-open No. 1983-
It is known as No. 135802 and No. 60-232002.

However, in the conventional product, when driving both tilling shafts to rotate with the power from the input shaft, a pair of left and right constant velocity ball joints are connected to the intersection of both tilling shafts 1, as shown in Fig. 8. A sprocket wheel 3 with a built-in sprocket wheel 2 is rotatably supported by a bearing 4, and a transmission chain 5 is wrapped around the wheel 3, and both tilling shafts 1 are rotated at a constant speed by power from an input shaft 6. As a result, the rotational drive mechanism is extremely complicated and specialized, and it is difficult to assemble it into the drive case 7 efficiently.

Moreover, as the rotation radius r of the sprocket wheel 3 becomes extremely large, the drive case 7 itself that houses the sprocket wheel becomes large in length along the vertical direction. Since the ground height of the case is relatively low, the bottom of the case easily comes into contact with the cultivated land, making it impossible to use it for deep plowing work. If this work is done forcibly, not only will excessive traction resistance be applied to the tractor, but it will also become an obstacle to making the plowing depth uniform, and accidents such as damage to the drive case 7 may occur. It turns out.

<Means for Solving the Problems> The present invention aims to improve such problems, and as a structure for this purpose, a tractor is provided at the upper end.
From the lower end of the center drive case where the input shaft, which is transmission-coupled with the PTO shaft, is supported, a pair of horizontal tilling shafts, horizontally oriented left and right, are distributed in such a way that they intersect in a widening U-shape when viewed from above. At the same time, in order to rotate both of the tilling shafts at a constant speed, the bevel gear shaft is placed in the upper position in the center drive case, and the reduction gear shaft is also placed in the middle position, so that they are in a horizontal state parallel to each other, and each rotation The bevel gear, which is freely suspended horizontally and fixed at the end of the bevel gear shaft, and the bevel pinion, which is fixed correspondingly to the rear end of the input shaft, are maintained in a meshing and rotating state, while the middle part of the bevel gear shaft is The small-diameter transmission gear fixed to the shaft and the large-diameter reduction gear correspondingly fixed to the middle part of the reduction gear shaft are maintained in a state of meshing rotation, and the transmission gear is connected in parallel to both ends of the reduction gear shaft. The invention is characterized in that a pair of left and right helical gears fixedly attached to the helical gears are meshed with helical gears fixedly attached to the protruding base ends of both tilling shafts at a constant intersecting angle.

<Example> Hereinafter, the specific configuration of the present invention will be described in detail based on the illustrated example. FIG. 1 shows the usage state of a tilling work machine, 10 is a tractor body, 11 is a tractor mounted on this. It is a three-point link mechanism that is moved up and down by a hydraulic cylinder device (not shown), and a hitch frame 12 for towing the work equipment is installed at the rear end.
are pivotally connected. Reference numeral 13 denotes a center drive case of a tilling work machine which is detachably attached to the hitch frame 12, and a pair of left and right shaft cylinders 14 are horizontally and symmetrically extended out diagonally rearward from the lower end of the center drive case in a continuous and integral manner. ing.

On the other hand, an input shaft 15 is projected forward from the upper end of the drive case 13, and is transmission-coupled to the PTO shaft (not shown) of the tractor body 10 via a universal joint shaft 16. It is adapted to accept rotational power taken out from the fuselage 10. Reference numeral 17 designates a pair of ball bearings rotatably supporting the input shaft 15, and reference numeral 18 designates a bevel pinion fixed to the rear end of the input shaft 15 so as to be able to rotate integrally therewith.

Further, 19 is a bevel gear shaft horizontally suspended to an upper position in the drive case 13 along the left-right direction intersecting the input shaft 15, and one end thereof is fitted with a spline or the like. A bevel gear 20, which is integrally rotatably mounted, is always meshed with the bevel pinion 18, and a small-diameter transmission gear 21 is also carved in the middle of the bevel gear shaft 19.

22 is a pair of left and right ball bearings rotatably supporting the bevel gear shaft 19; 23 is a drive case 13 that is parallel to the bevel gear shaft 19;
The large diameter reduction gear 24 fixed at the middle of the shaft is meshed with and rotated with the small diameter transmission gear 21, thereby generating the necessary power. It is designed to provide a deceleration effect.

Reference numeral 25 designates a pair of left and right helical gears which are installed at both ends of the reduction gear shaft 23 so as to be integrally rotatable by spline fitting or the like, and have symmetrical helical gears. 26 is reduction gear shaft 2
3 is a pair of left and right ball bearings. The pair of left and right helical gears 25 are set to have the same size, and the bevel pinion 18 and bevel gear 20 are also set to have the same size.

Furthermore, 27 is the shaft cylinder 1 of the drive case 13.
A pair of left and right tilling shafts are horizontally extended from the drive case 13 so as to pass through the drive case 13, and are divided into a wide-rear V-shape as a whole when viewed from above. In other words, both tilling shafts 27 maintain a constant gearing angle θ of approximately 20 to 35 degrees, for example.
They are placed in a mutually intersecting relationship.

At the base end portions of both tilling shafts 27 facing into the drive case 13, there is a helical gear 2 which meshes and rotates with the helical gear 25 on the reduction gear shaft 23.
8 are fixedly installed so as to be rotatable together. The pair of left and right helical gears 28 also have the same size and also have a symmetrical twisted tooth shape.
The intersection angle between the helical gear 28 on the tilling shaft 27 and the helical gear 25 on the reduction gear shaft 23 is indicated by the reference symbol γ.

Therefore, from the input shaft 15 to the drive case 13
The rotational power received inside is changed in direction by 90 degrees due to the meshing relationship between the bevel pinion 18 and the bevel gear 20, and also due to the meshing action between the small diameter transmission gear 21 and the large diameter reduction gear 24. Both helical gears 25, 28 mesh with each other while maintaining a constant crossing angle γ after being decelerated as required.
As a result, the power is transmitted equally to both tilling shafts 27. In that case, the upper bevel gear shaft 19, the middle reduction gear shaft 23, and the lower tilling shaft 27 are all installed in parallel on the same vertical line Y-Y, as is clear from FIG. Not limited to.

29 is a pair of left and right ball bearings that rotatably support both tilling shafts 27 to the shaft cylinder 14 of the drive case 13, and 30 is a pair of ball bearings on the left and right sides that rotatably support both tilling shafts 27 to the shaft cylinder 14 of the drive case 13; A plurality of rotary tiller claws are installed in the rotary tiller, and each of the rotary tiller claws is oriented in a radial direction from a common shaft 31 of the rotary tiller, and each tip thereof is bent inwardly. Further, numeral 32 is a disc plow each attached to the protruding tips of both tilling shafts 27 so as to be rotatable as one unit.
A concave curved surface forming the shape of a conical saucer is defined on the inner surface.

In this way, a plurality of rotary tilling claws 30 are placed at the inside positions of both tilling shafts 27 that intersect while maintaining a constant gearing angle θ, and one disk plow 32 is placed at the outside position, both of which are connected to the tilling shafts. 27
If installed in parallel so that it can rotate integrally with the fifth,
As shown in Fig. 6, the fine cultivated soil layer A crushed and stirred by the rotary tilling claws 30 can be deposited in a heaped state of a constant height H at a mutually intermediate position between the two tilling shafts 27, and at the same time, the fine cultivated soil layer A Since both the left and right sides of the tilled soil layer A can be covered and integrated with the rough tilled soil layer B that has been cut and turned over by the disc plow 32, a ridge M of a constant width W that can be used for planting crops can be formed in the same way. It can be said that it can be reliably shaped without fear of losing its shape due to rainwater, etc. Furthermore, if a soil cultivator 33 as shown in FIG. 1 is also attached, the ridge M can be shaped and solidified even more without fear of deformation.

However, as shown in a modified example in FIG. 7, it is also possible to similarly install only the disc plows 32 as a plurality of gearing bodies in parallel on the way where both tilling shafts 27 are exposed from the drive case 13. According to this configuration, it can be used as so-called soil preparation during the fallow period to improve the dry soil effect of the cultivated land.

<Effects of the Invention> In summary, in the present invention, a pair of horizontal horizontal tilling shafts 27 are connected to the center drive case 13 from the lower end of the center drive case 13 on which the input shaft 15, which is transmission-coupled with the PTO shaft of the tractor, is supported at the upper end. , and in order to rotate both tilling shafts 27 at a constant speed, a bevel gear shaft 19 is installed at an upper position in the center drive case 13. , and a reduction gear shaft 23 in the same middle position, horizontally suspended parallel to each other and freely rotatable, and a bevel gear 20 fixed to the end of the bevel gear shaft 19 and a bevel gear 20 fixed to the end of the input shaft 15. While keeping the bevel pinion 18, which is fixed correspondingly to the rear end, in a state of engagement and rotation, the transmission gear 21, which is also fixed to the middle part of the bevel gear shaft 19, has a small diameter, and the middle part of the reduction gear shaft 23. A correspondingly fixed large-diameter reduction gear 24 is maintained in a state of engagement and rotation, and a pair of left and right helical gears 25 fixed in parallel to both ends of the reduction gear shaft 23 are connected to both tilling shafts 27.
Because of the structure in which the helical gears 28 fixedly installed at the proximal end of each of the helical gears are meshed with each other at a constant intersection angle γ, the constant velocity ball Compared to the rotary drive mechanism using the insert 2 or the sprocket wheel 3 that incorporates the same, the vertical length of the drive case 13 can be significantly shortened, and the ground height H of the drive case 13 can be increased. As a result, the problem mentioned at the beginning can be reliably solved.

In other words, in the configuration of the conventional product, the sprocket wheel 3 has a built-in constant velocity ball joint 2 and is assembled at the intersection of both tilling shafts 1, so the rotation radius dimension r of the sprocket wheel 3 is As a result of the transmission chain 5 being wrapped around it, the bottom of the drive case 7 that encloses it and the sprocket wheel 3
The distance Z from the rotation center line X-X of Since only a pair of left and right helical gears 28 face this part, the above-mentioned interval distance Z can be substantially reduced to be equal to the rotation radius dimension R of the helical gears 28, and the ground height H of the drive case 13 can be reduced.
This means that it can be ensured as high as possible.

Moreover, in the present invention, on the reduction gear shaft 23 equipped with the helical gear 25 that meshes and rotates with the helical gear 28 on the tilling shaft 27, a large diameter reduction gear 24 that meshes and rotates with the small diameter transmission gear 21 on the bevel gear shaft 19 is provided. Since it is fixedly installed, it is extremely easy to give the necessary deceleration effect to the tilling shaft 27, and the deceleration gear 24 is faced to the intermediate portion between the pair of left and right helical gears 25 and 28. Together with this, it can be said that this is an extremely rational design.

In addition, since the rotational drive mechanism and bearing structure are simple overall, it is possible to make efficient use of the limited inside of the drive case 13, making it compact and efficient, and it can also be used as a necessary part. Since it is not particularly specialized and the number of parts is small, mass production can be expected to be as effective as possible, and in this sense it can be said to be of great practical benefit.

[Brief explanation of drawings]

Fig. 1 is a side view showing the use of the tilling machine according to the present invention, Fig. 2 is a cutaway perspective view of the center drive case, Fig. 3 is a side sectional view of the drive case, and Fig. 4 is a side view of the tiller according to the present invention. FIG. 5 is a plan view showing the meshing relationship of the helical gear; FIG. 5 is a plan view showing the tilling action; FIG. 6 is a rear view showing the formation of ridges by the action; FIG. 7 corresponds to FIG. 2. FIG. 8 is a developed cross-sectional plan view of a modified example, and FIG. 8 is a cross-sectional plan view showing the main parts of a conventional product for comparison with the present invention. 13... Center drive case, 15... Input shaft, 18... Bevel pinion, 19... Bevel gear shaft, 20... Bevel gear, 21... Transmission gear, 23... Reduction gear shaft, 24... Reduction gear, 2
5, 28... Helical gear, 27... Tilling shaft, X
-X...rotation center line (horizontal line), Y-Y...vertical line, Z...interval distance, R, r...rotation radius dimension,
θ...Guyang angle, γ...Cross angle.

Claims (1)

[Scope of Claims] 1. From the lower end of the center drive case 13, on which the input shaft 15, which is transmission-coupled with the PTO shaft of the tractor, is supported, a pair of left and right tilling shafts 27, which are horizontally oriented, are connected in plan view. The bevel gear shaft 19 is placed in the upper position in the center drive case 13, and the bevel gear shaft 19 is placed in the middle position in order to rotate both cultivating shafts 27 at a constant speed. A reduction gear shaft 23 is placed horizontally in parallel to each other so as to be freely rotatable, and a bevel gear 20 fixed to the end of the bevel gear shaft 19 corresponds to the rear end of the input shaft 15. While keeping the bevel pinion 18 fixedly fixed in a state of engagement and rotation, the transmission gear 21 with a small diameter, which is also fixedly fixed at the middle part of the bevel gear shaft 19, and the reduction gear shaft 23 are fixed correspondingly at the middle part. A pair of left and right helical gears 25 fixed in parallel to both ends of the reduction gear shaft 23 are connected to both tilling shafts 27.
A rotary drive mechanism for a tillage shaft, characterized in that it is meshed with helical gears 28 fixedly attached to the protruding base end portions of the tiller shaft at a constant intersecting angle γ.