AU2011200650B2 - Direct drill point assembly - Google Patents

Abstract

A direct drill point comprising an internal chamber adapted to receive an adaptor for location of the direct drill point thereon wherein, the internal chamber is defined by at least one wall which ends in a region presenting an 5 angle of less than 90 degrees to that wall, an adaptor with an external surface complimentary to the internal chamber and a direct drill point assembly comprising the direct drill point and adaptor. LC) LO I(n

Description

P/00/011 Regulation 3.2 AUSTRALIA Patents Act 1990 ORIGINAL COMPLETE SPECIFICATION STANDARD PATENT Invention Title: "DIRECT DRILL POINT ASSEMBLY" The following statement is a full description of this invention, including the best method of performing it known to me/us: 1 DIRECT DRILL POINT ASSEMBLY FIELD OF THE INVENTION The present invention relates to the field of agricultural apparatus. More particularly, this invention relates to a direct drill point assembly for the 5 preparation of soil prior to planting of seed. BACKGROUND OF THE INVENTION Direct drilling is a process of sowing seed without the necessity of first cultivating the soil. The use of a direct drilling approach provides a number of advantages including maintaining the microbial and biological balance of the 10 soil as well as preserving moisture and lessening the risk of erosion. All of these advantages stem from the fact that direct drilling disturbs only a relatively shallow depth of the soil to create a furrow in which the seeds are laid. Since direct drilling is employed on soils which have not been 15 previously cultivated or disturbed in any manner the soil may be relatively hard on the surface, particularly during drought conditions, and hence quite abrasive to any tool employed to break the surface crust and generate the furrow for planting. For this reason a direct drill assembly is normally employed which constitutes a series of adaptors or permanent members 20 affixed to a suitable item of farm machinery and a direct drill point or replaceable wear member located on each adaptor. Given that the direct drill points are in contact with soil they tend to have a limited lifetime which may be measured in terms of the area of soil 2 treated and may, depending on the particular design, be in the order of around 1000 hectares or so which figure relates to the area treated by machinery carrying an array of direct drill points. This planting lifetime is dependent on the soil type and the material used for the direct drill point or 5 wear member as well as its design. Typically, the direct drill point is fitted with a series of wear tiles which may be made from tungsten or any other suitably wear resistant material to maximise the lifetime of the product. Even with the current variations in design and the availability of a range of wear tiles, the direct drill point must be replaced on a relatively 10 regular basis, certainly much more often than the adaptor. Hence it would be desirable to provide for a direct drill point, as part of a direct drill point assembly, which has a suitably extended lifetime to thereby reduce the consumer's costs in replacing these items on a regular basis. SUMMARY OF THE INVENTION 15 In one broad form the invention resides in a wear member for use in agricultural direct drilling comprising a body having an external wear surface and an internal chamber, the internal chamber defined by walls which meet at a region shaped to provide a thickening of the walls relative to the walls meeting at a 90 degree angle. 20 In one form, although it need not be the only or indeed the broadest form, the invention resides in a direct drill point comprising: (a) a body having a rear end and a front end, the body converging downwardly from the rear end to the front end, and one or 3 more wear faces forming at least part of an external surface of the body; and (b) an internal chamber formed within the body and opening at the rear end thereof to receive an adaptor for location of the direct 5 drill point on the adaptor, wherein, the internal chamber is defined by at least one wall which ends in a region presenting an angle of less than 90 degrees to that wall. Preferably, the angle of the region is less than 70 degrees to the wall. In a preferred embodiment, the internal chamber is defined by at least 10 one wall which ends in a chamfered portion. Preferably, the internal chamber is defined, in part, by two side walls, an upper wall and a lower wall and at least one of the intersections of the upper or lower wall with the side walls is a chamfered portion. Suitably, each connection between the upper wall and the side walls 15 is a chamfered portion. If required, each connection between the lower wall and the side walls is a chamfered portion. Preferably, the chamfered portions are angled between 30 degrees to 60 degrees relative to the side walls, more preferably between 40 degrees to 20 50 degrees, even more preferably about 45 degrees. The internal chamber may contract approaching the front end of the body. Suitably, the chamfered portion of the internal chamber is aligned with 4 a chamfered region on the external surface of the body. A cross section of the internal chamber adjacent the rear end is octagonal. Preferably, the internal chamber cross section is an irregular octagon 5 with chamber side walls forming the longest walls of the octagon. The external surface of the body may further comprise an upper face, a lower face and two side faces at least one of which will be a wear face. The side faces may be generally triangular in shape. Suitably, the side faces have aligned apertures formed therein to 10 receive a fastening member for fastening of the drill point to the adaptor. The external surface of the body may be provided with one or more wear tiles. A direct drill point substantially as described herein with reference to the figures. 15 In a further form, the invention resides in an adaptor for a direct drill point assembly comprising: (a) a shank having a fastening means to attach the adaptor to an item of machinery; (b) a connecting region to connect the shank to a male portion, the 20 male portion having a body which converges downwardly on moving away from the connecting region towards an apex of the body, wherein, the body of the male portion comprises two substantially 5 triangular side faces each of which are in contact with at least one chamfered region. Preferably, the body of the male portion further comprises an upper surface and a lower surface separating the two side faces. 5 Suitably, each region joining the upper surface or the lower surface to one of the side faces is a chamfered region. Preferably, each side face is in contact with two chamfered regions which become substantially in contact adjacent the apex of the body. A cross section of the male portion immediately adjacent the 10 connecting region would be octagonal. Preferably, the cross section is an irregular octagon with the side walls of the body of the male portion forming the longest walls of the octagon. Suitably, a channel is formed through the body of the male portion to receive a fastening member. 15 Preferably, the channel opens at each side wall of the body. An adaptor for a direct drill point assembly substantially as described herein with reference to the figures. In yet a further form, the invention resides in a direct drill point assembly comprising: 20 (a) a direct drill point comprising a body having a rear end and a front end, the body converging downwardly from the rear end to the front end, an internal chamber formed within the body and opening at the rear end thereof, the internal chamber defined by 6 at least one wall which ends in a chamfered portion; and (b) an adaptor comprising a body which converges downwardly to an apex, the body comprising two substantially triangular side faces each of which are in contact with a chamfered region; 5 wherein, the shape of the internal chamber is complimentary to the shape of the body of the adaptor to enable location of the direct drill point on the adaptor such that the chamfered portion of the internal chamber and the chamfered region of the body are aligned. Preferably, the internal chamber of the direct drill point has four 10 chamfered portions which, upon location of the direct drill point on the adaptor, align with four corresponding chamfered regions on the body of the adaptor. Suitably, the body of the direct drill point further comprises aligned apertures passing therethrough into the internal chamber which, upon 15 location of the direct drill point on the adaptor, align with a channel formed through the body of the adaptor to receive a fastening member for fastening of the drill point to the adaptor. A direct drill point assembly substantially as described herein with reference to the figures. 20 Further features of the present invention will become apparent from the following detailed description. Throughout this specification, unless the context requires otherwise, the words "comprise", "comprises" and "comprising" will be understood to 7 imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers. BRIEF DESCRIPTION OF THE FIGURES In order that the invention may be readily understood and put into 5 practical effect, preferred embodiments will now be described by way of example with reference to the accompanying figures wherein like reference numerals refer to like parts and wherein: FIG 1 shows a perspective view of one embodiment of a direct drill point assembly; 10 FIG 2 shows a perspective view of a portion of one embodiment of a direct drill point, as seen in FIG 1; FIG 3A shows a side view of the direct drill point of FIG 2; FIG 3B shows a cross sectional view of a portion of the direct drill point shown in FIG 3A, along the line B-B; 15 FIG 4A shows a plan view of one embodiment of an adaptor, as seen in FIG 1; and FIG 4B shows a side view of the adaptor seen in FIG 4B. DETAILED DESCRIPTION OF THE INVENTION As used herein, the term "direct drill point" refers to a replaceable 20 wear member (planter point) which is adapted to be located on a permanent or fixed member to protect that permanent member when being forced through an upper layer of soil to create a furrow suitable for the planting of seeds.

8 As used herein, the term "adaptor" relates to a permanent or fixed member which may be releasably affixed to an item of agricultural machinery, onto which the direct drill point, otherwise known as planter point or wear member, is located. 5 As used herein, the term "direct drill point assembly" relates to the combination of a direct drill point and an accompanying adaptor, as previously described. As used herein, the term "chamfered" refers to a bevelled edge connecting two surfaces and is formed by the removal of an edge or corner 10 where the surfaces would otherwise have met. In this regard a merely sloping surface which does not also fit the above definition is not a chamfered surface. FIG 1 shows a perspective view of one embodiment of a direct drill point assembly 10 which comprises a direct drill point or wear member 100 15 and an adaptor 200 including a male portion 300. Direct drill point 100 has a body having an upper face 105, a lower face 110 and two generally triangular shaped side faces 115 of which only one can be seen in the perspective view of FIG 1. The body of the direct drill point 100 may be manufactured from cast steel or an equivalent material. 20 Connecting the side face 115 to the upper surface 105 is a chamfered region 120. At the lower end of side faces 115 are wings 130, which are an optional feature of the direct drill point 100. The wings 130, in use, may help to distribute soil, during passage of the direct drill point 100 therethrough, to 9 achieve an even distribution of soil over the seed and increase the chances of successful germination and growth. The side faces 115 and upper surface 105 will, in practice, have one or more wear tiles welded or otherwise attached thereto to resist wear in this 5 region and thereby preserve the lifetime of the direct drill point 100. The wear tiles may be made of tungsten, a tungsten alloy or like wear resistant material and have not been shown in the present figures for the sake of clarity. The body of direct drill point 100 has a rear end 135 and a front end 10 125 and can be seen to converge downwardly in dimensions when approaching front end 125. An internal chamber 140 is formed within the body of the direct drill point 100 and is shaped to receive the male portion 300 of the adaptor 200, which is of a complimentary shape. The internal chamber 140 is defined by two chamber side walls 145, a lower chamber 15 wall 150a and an upper chamber wall 150b and four chamfered portions 155. The chamber side walls 145 are substantially perpendicular to the lower 150a and upper 150b chamber walls and, if it were not for the chamfered portions 155, the internal chamber 140 could form a square or a rectangle, depending on the height of the chamber side walls 145. The 20 presence of the chamfered portions 155 results in an octagon shaped cross section. The side faces 115 have aligned apertures 160 formed therein allowing passage of a fastening means from the external surface into the internal chamber 140.

10 Typical prior art direct drill points have an internal chamber which is of a square or rectangle shape, i.e. which does not have chamfers. This means that the walls of the direct drill point body, at the corners of the square or rectangle are considerably thinner than along the side and upper and lower 5 walls since the external wear surface of the direct drill point body is typically chamfered as shown in FIG 1 to provide an appropriately angled surface for passage through the soil. Thus, it can be envisaged that, using the direct drill point 100 shown in FIG 1, but without the chamfered portions 155, the corners of the rectangle formed on the internal chamber 140 would be closer 10 to the chamfered region 120 on the external surface of direct drill point than the side walls 145 would be to the side face 115. In practice, this prior art design results in the wall of the direct drill point between chamfered region 120 and the corner of the internal chamber 140 being the weakest point of the direct drill point 100. During use, even 15 with the presence of wear tiles, the constant wear inflicted by the ground will wear out that region while the remainder of the external surface of the direct drill point is still in good working condition. The direct drill point must, therefore, be replaced earlier than would otherwise be necessary, at the expense of the user. 20 As described, the solution to this problem presented herein is to chamfer the corners of the internal chamber 140 to form chamfered portions 155. The thickness of the wall between the internal chamber 140 and the external surface of direct drill point 100 at these chamfered portions 155 is at 11 least as great as that between the side walls 145, or the lower 150a or upper 150b walls, and their adjacent region of the external surface of the direct drill point 100. This means that the direct drill point 100 will have a longer operational lifespan thus reducing replacement costs for the user. 5 To reciprocate with the chamfered portions 155 of the internal chamber 140 the adaptor 200, in particular the male portion 300, must be provided with a complimentary shape. The adaptor 200 in FIG 1 comprises a shank 205 having means to attach to an item of agricultural machinery. The shank 205 leads into a connecting region 210 which ends in male portion 10 300 designed to sit, at least partially, with the internal chamber 145 of the direct drill point 100. The adaptor may be formed from cast steel and similar materials as are known in the art. The male portion 300 comprises an upper surface 305, a lower surface 310 and two generally triangular side faces 315 which are provided 15 with aligned apertures 320. The apertures 320 are continuous to form a channel passing through the body of the male portion 300 to allow a fastening means such, as a locking pin, to pass therethrough. In use, the male portion 300 will be located within the internal chamber 140 of the direct drill point 100 and the two can be releasably fastened together by passing a 20 locking pin or like mechanism through an aperture 160 formed in one of the side faces 115 of the direct drill point 100, then through an aligned aperture 320 formed in a side face 315 of the male portion 300 before passing out the other side through the other apertures 320 and 160.

12 The male portion 300 further comprises adaptor chamfered regions 325 on its external surface which are formed between each side face 315 and the adjacent upper surface 305 and lower surface 310. The adaptor chamfered regions 325 correspond with the chamfered portions 155 of the 5 internal chamber 140 of the direct drill point 100 such that the male portion 300 can be inserted therein to the extent that an apex 330 at the narrowest point of the male portion will be able to sit adjacent the front end 125 of the direct drill point 100. Prior art adaptors will typically have an extension corresponding, in use, to the male portion 300 but will not have the adaptor 10 chamfered regions 325. In one embodiment, the adaptor chamfered regions 325 form at least 30% of the surface area of the male portion 300, preferably at least 35%. As well as providing a corresponding shape to that of the internal chamber 140 of the direct drill point 100 the adaptor chamfered regions 325 15 provide advantages in reducing the weight of the adaptor 200 and the amount of materials used in its construction. Further, the design of the male portion 300 is slimmer than is found in the prior art, an attribute which is contributed to by the adaptor chamfered regions 325. This allows for a general thickening of all of the walls forming the internal chamber 140 of the 20 direct drill point 100, again prolonging the lifetime of the product in operation. FIG 2 shows a perspective view of a portion of one embodiment of the direct drill point 100, as seen in FIG 1. The front end 125 of the direct drill point 100 can be clearly made out. In the embodiment shown, it takes the 13 form of a blunt wall but may be of any shape suitable for drill point contact with the ground in preparation for seeding and the like. The upper face 105 and chamfered regions 120 are shown and can be seen to slope downwardly from the rear end 135 to the front end 125. The generally triangular shape of 5 the side faces 115 of the direct drill point 100 are evident, although the triangular faces may or may not narrow into an actual point. FIG 3A shows a side view of the direct drill point 100 of FIG 2 while FIG 3B shows a cross sectional view of a portion of the direct drill point 100 shown in FIG 3A, along the line B-B. The section B-B gives a clear indication 10 of the shape of the internal chamber 140 and the contribution made, to the thickness of the walls making up the rear end 135 and forming the internal chamber 140, by the chamfered portions 155. The elongate shape of the internal chamber 140, due to the height of the chamber side walls 145, is indicated and this provides for a further 15 advantage of the present direct drill point assembly 10. This elongate nature means that the external side faces 115 of direct drill point 100 are wider closer to the rear end 135 than would be found in prior art devices. This allows more surface area for the provision of larger diameter apertures 160 and hence enables the use of larger and stronger locking pins. In practice a 20 typical drill point would have a 6 mm fastening pin located within the apertures 160 to attach it to a corresponding adaptor. The present direct drill point 100, having the elongate internal chamber 140, allows the comfortable use of an 8 mm pin. This provides for an increase in strength in this critical 14 area. Great stress is placed on the fastening pin during use of a direct drill point assembly and failure of the pin is not uncommon resulting in time lost in inadequate preparation of the soil for seeding as well as time lost in repair. Increasing the strength of the fastening pin by allowing for a wider or greater 5 overall surface area of side face 115 to accommodate a larger pin greatly reduces the risk of pin failure. It will be appreciated that although the internal chamber 140 shown in the figures is an irregular or elongate octagon in cross section, other shapes are considered to fall within the scope of the present invention so long as 10 they provide for a chamfered portion within the walls defining said chamber 140 such that those walls are substantially the same thickness along their entire extent thereby avoiding any weak points likely to cause early failure of the direct drill point 100. The male portion 300 of the adaptor 200 would be shaped to correspond with and insert into the internal chamber 140 in all 15 cases. For example, the internal chamber 140 of the direct drill point 100 may be of a kite or rhombus shape or generally triangular. Alternatively, the internal chamber 140 may, instead of the chamfered portions 155, have formations such as curves or bulging portions which protrude into the internal chamber 140. So long as these formations result in 20 a previously thinner part of the chamber walls becoming thickened to a level similar to the rest of the walls, for example the side walls, then such formations are considered to be within the scope of the present invention. In one general embodiment, the internal chamber is defined by at 15 least one wall which ends in a region presenting an angle of less than 90 degrees to that wall, preferably less than 70 degrees, more preferably less than 60 degrees. The region connecting with the wall cannot, therefore, be a standard corner formed by the meeting of vertical and horizontal walls as is 5 the practice in the prior art. This embodiment includes the use of a chamfered portion 155 as described herein which, in the embodiment shown, is at an angle of approximately 45 degrees to its adjacent side wall 145. Curves, bulges and other non-geometric shapes will also fall within the limitation of a region connecting with a wall at an angle of less than 90 10 degrees since such an angle will result in a thickening of the internal chamber 140 walls in that area thereby addressing the weakness of the prior art corner areas. The chamfered portions 155, described herein, are, however, preferred embodiments providing advantageous gains in the strength of the direct dill point 100. 15 The adaptor 200 will, of course, have a corresponding region which may be described as a cut away region to accommodate the curving, bulging or like shape formed at the meeting of the internal chamber 140 side walls 145 and lower 150a or upper 150b surfaces. This region will always be generally sloping i.e. it will be at an angle less than the 90 degree corner 20 which would be formed if these side walls 145 and surfaces 150 a and 150b were vertical and horizontal, respectively, when oriented as shown in the figures. This is, again, to accommodate the additional thickening of the internal chamber 140 walls in the corresponding region. These two 16 components will form the direct drill point assembly. FIG 4A shows a plan view of one embodiment of the adaptor 200, as seen in FIG 1 and FIG 4B shows a side view of the adaptor 200, seen in FIG 4B. The chamfered nature of the male portion 300 can be seen in FIG 4A 5 where a chamfered region 325 is seen to be formed either side of the upper surface 305. The chamfered regions 325 slope down and outwardly to the side faces 315. Fastening screws 215 are shown in FIG 4A which allow attachment to the item of farming machinery used for direct drilling. FIG 4B shows how connecting region 210 allows for a suitable angled to be obtained 10 such that the direct drill point 100, when located over the male portion 300, will be oriented to the ground at the appropriate angle for correct soil parting. In summary, an improved direct drill point assembly 10 is provided which comprises the direct drill point 100 described herein having an internal chamber 140 with a number of chamfered portions 155. These are located to 15 connect the chamber side walls 145 and the upper and lower chamber walls 150a and 150b, respectively, such that their placement results in relatively uniform chamber wall thickness. This avoids the formation of weak spots in the walls which are observed in prior art devices where the corner of an internal chamber is close to a chamfered external surface thereby resulting in 20 failure of the device following a relatively short operational lifetime. Throughout the specification the aim has been to describe the preferred embodiments of the invention without limiting the invention to any one embodiment or specific collection of features. It will therefore be 17 appreciated by those of skill in the art that, in light of the instant disclosure, various modifications and changes can be made in the particular embodiments exemplified without departing from the scope of the present invention. 5 10 15 20

Claims (19)

1. A direct drill point comprising: (a) a body having a rear end and a front end, the body converging downwardly from the rear end to the front end, and one or 5 more wear faces forming at least part of an external surface of the body; and (b) an internal chamber formed within the body and opening at the rear end thereof to receive an adaptor for location of the direct drill point on the adaptor, 10 wherein, the internal chamber is defined, in part, by two side walls, an upper wall and a lower wall and at least one of the intersections of the upper or lower wall with the side walls is a chamfered portion.

2. The direct drill point according to claim 1 wherein each intersection between the upper wall and the side walls is a chamfered portion. 15

3. The direct drill point according to claim I wherein each intersection between the lower wall and the side walls is a chamfered portion.

4. The direct drill point according to claim I wherein the chamfered portion is angled between 30 degrees to 60 degrees relative to the side walls. 20

5. The direct drill point according to claim 1 wherein the chamfered portion of the internal chamber is aligned with a chamfered region on the external surface of the body.

6. The direct drill point according to claim 1 wherein a cross section of 2254653v1 19 the internal chamber adjacent the rear end is octagonal.

7. The direct drill point according to claim 6 wherein the chamfered portions result in the thickness of the walls of the internal chamber in that area being substantially the same as or greater than the thickness of the side 5 walls of the internal chamber.

8. The direct drill point according to claim I wherein the external surface of the body further comprises an upper face, a lower face and two side faces at least one of which will be a wear face.

9. The direct drill point according to claim 8 wherein the side faces have 10 aligned apertures formed therein to receive a fastening member for fastening of the drill point to the adaptor.

10. The direct drill point according to any one of the preceding claims wherein the external surface of the body is provided with one or more wear tiles. 15

11. An adaptor for a direct drill point assembly comprising: (a) a shank having a fastening means to attach the adaptor to an item of machinery; (b) a connecting region to connect the shank to a male portion, the male portion having a body which converges downwardly on 20 moving away from the connecting region towards an apex of the body, wherein, the body of the male portion comprises two substantially triangular side faces each of which are in contact with at least one cut away 2254653v1 20 region, wherein the cut away region is a chamfered region.

12. The adaptor according to claim 14 wherein the body of the male portion further comprises an upper surface and a lower surface separating the two side faces. 5

13. The adaptor according to claim 15 wherein each region joining the upper surface or the lower surface to one of the side walls is a chamfered region.

14. The adaptor according to claim 15 wherein each side face is in contact with two chamfered regions which substantially contact one another adjacent 10 the apex of the body.

15. The adaptor according to claim 15 wherein a cross section of the male portion immediately adjacent the connecting region is octagonal.

16. The adaptor according to claim 14 wherein a channel is formed through the body of the male portion to receive a fastening member therein. 15

17. A direct drill point assembly comprising: (a) a direct drill point comprising a body having a rear end and a front end, the body converging downwardly from the rear end to the front end, an internal chamber formed within the body and opening at the rear end thereof, the internal chamber is defined, in part, by 20 two side walls, an upper wall and a lower wall and at least one of the intersections of the upper or lower wall with the side walls is a chamfered portion; and (b) an adaptor comprising a body which converges downwardly to 2254653v1 21 an apex, the body comprising two substantially triangular side faces each of which are in contact with a chamfered region; wherein, the shape of the internal chamber is complimentary to the shape of the body of the adaptor to enable location of the direct drill point on the 5 adaptor such that the chamfered portion of the internal chamber and the chamfered region of the body are aligned.

18. The direct drill point assembly according to claim 18 wherein the internal chamber of the direct drill point has four chamfered portions which, upon location of the direct drill point on the adaptor, align with four corresponding 10 chamfered regions on the body of the adaptor.

19. The drill point assembly according to claim 18 wherein the body of the direct drill point further comprises aligned apertures passing therethrough into the internal chamber which, upon location of the direct drill point on the adaptor, align with a channel formed through the body of the adaptor to 15 receive a fastening member for fastening of the drill point to the adaptor. 2254653v1