GB2111812A

GB2111812A - Cultivating device

Info

Publication number: GB2111812A
Application number: GB08234984A
Authority: GB
Inventors: Shigeki Sano
Original assignee: Individual
Current assignee: Individual
Priority date: 1981-12-18
Filing date: 1982-12-08
Publication date: 1983-07-13
Also published as: FR2518360A1; IT8268473A0; DE3246045A1; JPS58107101A; BR8207349A; JPS6152642B2

Abstract

A rotary cultivating device for mounting on an agricultural tractor 8 comprises cultivating tubes 1 and cultivating blades 7 secured to the peripheral surfaces of the cultivating tubes. Each of the cultivating tubes 1 is formed into a substantially equilateral triangular cross-sectional shape and has large side faces 1a to which the blades 7 are fixed and small side faces 1b forming chamfered corners of the triangular section. As the tubes are rotated by a driveshaft 9 the triangular sections of the tubes 1 causes the tubes themselves as well as the blades 7 to share in the cultivation of the soil and this decreases the resistance to movement through the soil of the device as a whole. <IMAGE>

Description

SPECIFICATION Cultivating device This invention relates to a cultivating device for installation on an agricultural power-driven machine such as a power-driven cultivator, or a tractor. The invention is particularly concerned with improve ments in cultivating tubes to which cultivating blades are secured and which in use, are rotated.

Various cultivating tubes, which are secured to opposite sides of a driving casing, which rotate the tubes, of a n an agricultural power-driven machine such as a cultivator or a tractor, are known. They include cultivating tubes having a circular, octagonal, or hexagonal cross-section. With cultivating tubes hav ing a circular cross-section, during cultivation, the soil which is being cultivated is cultivated by means of the cultivating blades but is merely pressed by the tubes against the uncultivated soil, so that no cultivation can be performed by the cultivating tubes themselves. Because ofthis, increased resistance to cultivation occurs.Furthermore, with cultivating tubes having an octagonal or a hexagonal cross section, the soil can be slightly cultivated at the corners of the tubes and the cultivating resistance can be slightly decreased, however, no effective cultivation is still achieved by the tubes themselves.

Resistance to cultivation as referred to in this specification includes frictional resistance and compressive resistance applied to the cultivating tubes and the cultivating blades carried by the tubes, and the cohesive force, adhesive force and shear resistance of the soil, indeed the whole resistance to movement of the cultivating device through and over the soil.

Cultivators of the tilling type which perform the cultivation simultaneously with their travel over the soil and which have only a small driving unit, have not been able to cultivate highly viscous or cohesive soil, or wet soil because of the presence of high resistance to cultivation. This results in very inefficient cultivating work. Thus, the need has arisen for some means for decreasing the resistance to cultivation by such cultivators to make the cultivating work satisfactory even with small driving units. However, difficulties have been encountered in achieving this decrease.

The object of the present invention is to provide a cultivating device as initially described which is capable of decreasing the resistance to cultivation to enable it to perform efficient cultivating work even in highly cohesive or viscous soil.

To this end, according to this invention, a cultivating device includes a cultivating member comprises a tube of substantially equilateral triangular crosssection, the tube having three large side faces forming the sides of the triangular cross-section and three small side faces forming chamfers at the corners of the triangular cross-section, at least one cultivating blade fixed to each large side face of the tube, and means for mounting the or each tube on a tractor or other power unit and for rotating the or each tube about its axis.

Tubes of triangular cross-section have never been used or even studied in the cultivator industry perhaps because such tubes tend to be rocked violently in the vertical direction during the cultivat ing work and the digging-in of the corner portions of the tubes into the soil tends to retard the advance of the cultivator. However, the tubes of the device in accordance with the present invention are so shaped and arranged, owing to the provision of the large side side faces and the small side faces forming the chamfered corners, that when cultivating work is performed with the device which in operation is secured to a driving case of a n an agricultural tractor or other travelling power unit, then the soil is scraped out and lumps of soil are thrown rearwardly by the small side faces or corner portions between the large side faces.In this way, the cultivating resistance is considerably decreased through the agency of the corner portions and this facilitates the travel of the power unit. The cultivating work can thus be performed very efficiently and the above-described disadvantages can be obviated. The cultivating tubes can be prevented from biting into the soil to an extreme extend due to the presence of the small side faces even though the cultivating tubes have substantially equilateral triangular cross-sections, and the rocking of the tubes in the vertical direction and the advancing performance of the cultivating tubes can be improved, there by enabling the achievement of the above-described object.

In a preferred construction, the cultivating member comprises a plurality of the tubes connecting together co-axially. Preferably, also, cultivating tubes which are disposed adjacent to each other are angularly offset from each other so that a suitable phasic difference in angle is formed between them in a cross-sectional plane. In this way, irregularities in the cultivating resistance during rotation of the assembly of triangular cultivating tubes as a whole are eliminated to further improve the cultivating efficiency, thereby enabling the better achievement of the above-described object.

Several examples of devices in accordance with the invention will now be described with reference to the accompanying drawings in which: Figure 1 is a perspective view showing a driving casing of an agricultural tractor or cultivator carrying two devices in accordance with the present invention; Figure 2 is a front view of Figure 1; Figure 3 is a right side view of Figure 2; Figure 4 is an enlarged sectional view taken along the line IV - IV in Figure 2; Figures Sand 6 are enlarged side views showing other embodiments of the triangular cultivating tubes different from each other, which are used in the present invention; Figure 7 is a perspective view showing a further embodiment in which the triangular cultivating tubes are continuously provided, which is used in the present invention; Figure 8 is a sectional view of Figure 7;; Figure 9 is an enlarged perspective view of the essential portions showing a connecting portion in an embodiment in which the triangular cultivating tubes are made slidable on each other, which are used in the present invention; Figures 10 and 11 are sectional views showing the internal combustion of other embodiments different from each other, in which the triangular cultivating tubes are made slidable on each other, for use in the present invention; and Figure 12 is a perspective view of the essential portions showing a further embodiment of the cultivating tube used in the present invention.

Description will hereunder be given of the embodiments of the present invention with reference to the drawings.

In one embodiment shown in Figures 1 through 4, a cultivating tube 1 is constructed such that side plates are solidly secured to opposite end faces of a tubular member formed of a metal plate such as a steel plate. This cultivating tube 1 is formed into substantially a regular triangular shape in crosssection perpendicularly intersecting the axial line thereof, respective surfaces of this tubular crosssection in the longitudinal line thereof are designated as large surface portions 1a, la and la, respectively, and corner portions between the large surface portions 1a and 1a disposed adjacent to each other are chamfered to provide small surface portions 1 b, 1b and 1 b. In this case, the respective large surface portions 1 a and the small surface portions 1 b, as shown in Figures 1 through 3 and as indicated by solid lines in Figure 4, are formed into flat shapes, as indicated by two-dot chain lines in Figure 4 and as shown in Figure 5, formed into slightly bulged-out convex shapes, further as shown in Figure 6, formed into slightly concave shapes, or, as not shown though, the large surface portions 1 a are formed into slightly convex shapes and the small surface portions 1 b are formed into slightly concave shapes, or vice versa. Experimentally, it is preferable that the width of the large surface portion la, i.e. the length thereof in the cross section perpendicularly in tersecting the axial line is more than about three times the width of the small surface portion 1 b (in the drawing, about five times).

The triangular cultivating tube 1 is penetratingly provided at the center in cross-section thereof with an axially directed through-hole 2. In many cases, the through-hole 2 is formed by a polygonal pipe (Refer to the drawing). Furthermore, each of the large surface portions 1a of the triangular cultivating tube is affixed thereto with each one of sheathshaped holders 6 which are different in position in the axial line of the tube from one another, whereby the respective holders 6 are different in angular phase through 120 degrees from one another, and are affixed in a manner to be shifted in the axial direction of the tube from one another. Proximal ends of cultivating blades 7 are inserted into the holders 6, respectively, and detachably affixed thereinto by means of bolts and nuts.These cultivating blades 7 each comprise a vertical cutter portion V extending from the proximal end for fixing to an intermediate portion and a horizontal cutter portion H formed at the forward end of the vertical cutter portion V. The vertical cutter portion V is extended in a direction perpendicularly intersecting the axial line of the cultivating tube 1 and curved in the aforesaid plane perpendicularly intersecting the axial line of the cultivating tube 1 in a direction opposite to the rotating direction of the cultivating tube 1 (Refer to an arrow P in Figure 3). On the other hand, the horizontal cutter portion H at the forward end is directed to the right or left along the axial line of the triangular cultivating tube 1 and bent into a substantially horizontal shape, whereby the cultivating blade 7 is generally formed into a three dimensionally curved surface.

The cultivating devices, each of which is constructed such that the cultivating blades 7 are secured to the triangular cultivating tube 1, are bysymmetrically, detachably mounted through the aforesaid throughholes 2 onto a hexagonal columnshaped shaft 9 projecting to opposite sides from a driving case 8 downwardly bulged from an agricultural power traveler such as a cultivator or a tractor (Refer to Figures 1 and 2). In order to perform the cultivating work by use of the present embodiment as constructed above, the cultivating shaft 9 should be driven to rotate the cultivating devices in a direction indicated by the arrow P in Figure 3 in the same manner as with the conventional cultivating devices commonly used.

The present embodiment with the abovedescribed arrangement can offer the following advantages.

More specifically, in the present embodiment, the cross section of the cultivating device perpendicularly intersecting the axial line thereof is formed into a substantially regular triangular shape, respective surfaces thereof are made to be large surface portions 1 a, and corner portions between the large surface portions 1a adjacent to each other are chamfered into small surface portions 1 b, to thereby provide the triangular cultivating tube 1. The respective large surface portions la of the thus provided triangular tube-shaped cultivating tube 1 are secured thereto with the cultivating blades 7, whereby the cultivating tubes 1 can scrape out the soil rearwardly without pressing the soil against the uncultivated soil, so that the cultivating resistance can be reduced to a considerable extent. Detailed description will now be given of this respect.The triangle is a polygon which has the least number of corners in cross-section. A soil scraping angle a of the triangular cultivating tube 1 is far smaller than the soil scraping angle of the conventional cultivating tube such as an octagonal or a hexagonal one. Here, the soil scraping angle a refers to an angle made by a line connecting the center 0 of the triangular cultivating tube 1 to an end of the large surface of the cross section of the large surface portion 1a. Due to the presence of the small soil scraping angle a, end edges of the large surface portions 1a (the corner portions between the large surface portions 1a and the small surface portions 1 b and thereabout) function as cultivating blades, scraping out the soil and throwing many lumps of soil rearwardly. In consequence, with the conventional cultivating tubes having a circular cross-section and the like, a resistance of pressing the soil against the soil and a cohesive force of the soil adhering to the cultivating tubes acts on to a considerable extent, to thereby increase the cultivating resistance. Whereas, according to the present invention, through the cultivating blade-like action, the cultivating resistance such as the resistance of pressing the soil against the soil can be decreased to a great extent, thereby enabling to obtain a suitable advancing performance. Properly speaking, the cutting of the soil, lifting of the lumps of said, throwing the lamps of soil rearwardly and the like would otherwise have been performed exclusively by the cultivating blades.Whereas, according to the present invention, through the cultivating blade-like action, the cultivating work is effected within a hypothetical circle of the triangular tube-shaped cultivating tubes 1 by means of the cultivating tubes 1, whereby only the outer peripheral portion is cultivated by the cultivating blades 7 to reduce the cultivating resistance such as the cutting resistance to a great extent, so that the cultivating work by means of the triangular cultivating tubes 1 can be combined with the cultivating work by means of the cultivating blades 7 to produce a very high cultivating efficiency.Thus, an epochal invention can be provided, in which though the adoption of a simplified construction having a substantially regu lartriangular cross-section, even when the driving source is small and/or the soil has a high viscosity or the like, the cultivating work can be achieved with high efficiency. The results of the experiments show that a land under cultivation, which has heretofore been difficult to be cultivated by means of a small driving force such as about two or three horsepower, can be satisfactorily cultivated by means of a small driving force of about two or three horsepower when the cultivating device according to the present invention is used. A mere regular triangular cultivating tube 1 would sink into the soil to an extreme extent.However, according to the present invention, the cultivating tubes are formed into a substantially regular triangular shape with the respective corners chamfered into the small surface portions 1 b, whereby the cultivating devices do not easily sink into the soil, so that the cultivating portions can be prevented from sinking into the soil to an extreme extent during the cultivating work, thus enabling to obtain a satisfactory control lability of the cultivating device.

Furthermore, even on soft lands under cultivation such as a sandy land, a land of volcanic ashes and a land of diatom earth, the cultivating device can avoid unnecessary lost motions, so that the satisfactory advancing and cultivating can be attained. Further, the triangular cultivating tube 1 constituted by the small surface portions 1 b and the large surface portions 1 a has many bent corners in looking in cross section, which fact increases the modulus of section in value, thereby enabling to increase the structure as a whole in mechanical strength. In consequence, the cultivating tube 1 can obtain a satisfactory mechanical strength even if it is formed of a thin plate material.

Figures 7 and 8 show another embodiment of the present invention, in which two triangular cultivating tubes 1 are continuously provided at one side of the driving case 8. In this embodiment, the triangular cultivating tubes 1 and 1 disposed adjacnetto each other have a suitable phasic difference in angle from each other in a plane perpendicularly intersecting the axial line thereof. More specifically, in mounting a second triangular cultivating tube 1 to a first triangular cultivating tube 1 to a first triangular cultivating tube 1 disposed on the side of the driving case 8, the cultivating tubes 1 and 1 have a suitable phasic difference in angle (about 20 to 70 degrees, and about 60 degrees in this embodiment) from each other.These cultivating tubes 1 and 1 are solidly secured to each other by suitable means such as welding orthreadable coupling, and the throughhole 2 for receiving the cultivating shaft 9 is provided only in the first cultivating tube 1.

The present embodiment with the abovedescribed arrangement can offer the function and effects similarto those in the embodiment shown in Figures 1 through 4, and further, add the following advantages. More specifically, in the present embodiment, the action of scraping out the soil by the end edges of the large surface portions la of the continuously connected triangular cultivating tubes 1 and 1 as these tubes rotates during the cultivating work (the cultivating blade-like action) is in a substantially continued condition in looking from sideways, thereby enabling to obtain a very smooth cultivating rotation.To describe this functional effect in more detail, as the cultivating rotation is performed, the soil is scraped out by one end edge of the large surface portion 1a of the first triangular cultivating tube 1, immediately after, the soil is scraped out by one end edge of the large surface portion 1 a of the second triangular cultivating tube 1, and the above-described actions are repeated (the first triangular cultivating tube 1 and the second triangular tube 1 may be reversed in order, whereby 2 time interval between the scrapes of the soil can be made shorter than that when only one triangular cultivating tube 1 is used in the cultivating work, so that the action of scraping the soil can be made substantially continuous to obtain a cultivating condition where the rotation of the cultivation tubes is very smooth, thus enabling to improve the cultivating efficiency in the continuous cultivation even with a small driving force. Furthermore, a plurality of triangular cultivating tubes 1 connected to one another may be used to accommodate an increased width of cultivation.

Figure 9 shows another embodiment of the connecting portions when the cultivating tubes 1 are connected to each other, in which a triangular joint tube 3 having a cross-section perpendicularly in tersecting the axial line of the cultivating tubes 1, which is similar to and slightly smaller than the aforesaid triangular cultivating tube 1, is affixed to one end of the second triangular cultivating tube.

Corresponding to the above, in the larger surface portions 1a and the small surface portions 1 b of the first triangular cultivating tube at one end of the first triangular cultivating tube 1, a space 4 is formed, and the aforesaid triangular joint tube 4 is received in the space 4 in a manner to be slidable in the axial line thereof, whereby the general arrangement permits the adjustment in the widthwise direction of the cultivating tubes. Upon completion of the adjustment, locking is effected by means of pins, locking bolts or the like.

The present embodiment with the abovedescribed arrangement can add the advantage that the width of cultivation can be suitably increased, in addition to the functional effects as described in the preceding embodiments.

Figures 10 and 11 show another embodiments different from each other, of driving force transmitting means when the connecting construction by means of the triangular joint tube 3 as shown in Figure 9 is adopted. More specifically, in the embodiment shown in Figure 10, the first triangular cultivating tube 1 disposed close to the driving case 8 and the second triangular cultivating tube 1 disposed farther from the driving case 8 are formed therethrough with through-holes 2 formed of hexagonal pipes, respectively, a connecting shaft tube 5 formed of a hexagonal pipe is provided in these throughholes 2 in a manner to be closely coupled to the inner surface of the through-holes 2, and the aforesaid cultivating shaft 9 is coupled into this connecting shaft tube 5.Furthermore, in the embodiment shown in Figure 11, the pipe constituting the through-hole 2 of the first triangular cultivating tube 1 is extended and projected toward the second triangular cultivating tube 1, forming the connecting shaft tube5 by itself.

In either one of the above-described embodiments, the driving force can be satisfactorily transmitted and the cultivating devices as a whole can be adjusted in their lengths in the axial direction thereof. Furthermore, the embodiment shown in Figure 11 is advantageous in that the parts may be reduced in number.

Figure 12 shows another embodiment of the cultivating blade 7 according to the present invention, in which the cultivating blade 7 is constructed such that the longitudinal cutter portion V is formed into a straight-line shape, and the blade is generally formed into a L-shape.

The present embodiment with the abovedescribed arrangement can offer the advantage similar to those of the preceding embodiments.

In addition, in the embodiments shown in Figures 7 through 11, description has been given of the construction in which two triangular cultivating tubes 1 are connected to each other in the axial direction thereof. However, the present invention need not necessarily be limited to this, but three or more triangular cultivating tubes can be connected to one another. In this case, it is effective for preventing rocking in the vertical direction and irregularities in rotation of the cultivating device as a whole that a suitable phasic difference in angle is given to a third and further cultivating tubes 1 relative to the respective preceding cultivating tube 1. Furthermore, the means for mounting the cultivating blades 7 to the large surface portions 1 a need not necessarily be limited to the holders 6, bolts and nuts, but, the cultivating blades 7 may be directly affixed to the large surface portions 1 a by welding or the like, or may be affixed to the holders 6 by welding or the like. Further, in the embodiments shown in Figures 9 through 11, the triangular joint tube 3 has been affixed to one end of the second triangular cultivating tube 1, but, on the contrary, the joint tube 3 may be affixed to one end of the first triangular cultivating tube 1 and the space 4 may be formed in one end of the second triangular cultavating tube 1.

Claims

1. A cultivating device which includes a cultivating member comprising a tube of substantially equilateral triangular cross-section, the tube having three large side faces forming the sides of the triangular cross-section and three small side faces forming chamfers at the corners of the triangular cross-section, at least one cultivating blade fixed to each large side face of the tube, and means for mounting the or each tube on a tractor or other power unit and for rotating the or each tube about its axis.

2. Acultivating device according to Claim 1, wherein the width of each large side face in a direction perpendicular to the axis of the tube is more than three times the width of each small side face of the tube.

3. A cultivating device according to Claim 1 or Claim 2, in which each large side face bulges outwards so that it is slightly convex as seen in cross-section of the tube.

4. A cultivating device according to Claim 1 to Claim 2, in which each large side face is recessed inwards so that it is slightly concave as seen in cross-section of the tube.

5. A cultivating device according to any one of Claims 1 to 3, in which each small side face bulges outwards so that it is slightly convex as seen in cross-section of the tube.

6. Acultivating device according to Claim 1, Claim 2, or Claim 4, in which each small side face is recessed inwards so that it is slightly concave as seen in cross-section of the tube.

7. A cultivating device according to any one of the preceding Claims, in which the cultivating member comprises a plurality of the tubes connected together co-axially.

8. A cultivating device according to Claim 7, in which adjacent tubes which are connected to each other are angularly offset.

9. A cultivating device according to Claim 7 or Claim 8, in which adjacent tubes are connected together by a joint tube of triangular cross-section which is fixed to one of the tubes and fits the other tube to enable the other tube to slide axially relative to the one tube and the joint tube to enable the overall axial length of the cultivating member to be adjusted.

10. A cultivating device according to any one of the preceding Claims, in which the mounting means includes a pipe for mounting on a driveshaft of the power unit, the pipe extending co-axially through and being fixed to the tube or one of the tubes of the cultivating member and extending through a hole through an internal member of an adjacent tube, when there are more than one tube, to enable the driveshaftto transmit power to both tubes.

11. A cultivating device according to Claim 1, substantially as described with reference to Figures 1 to 4, or Figure 5, or Figure 6, or Figures 7 and 8, or Figure 9, or Figure 10, or Figure 11, or Figure 12, of the accompanying drawings.