IES20020715A2 - Roller and mount assemblies - Google Patents

Abstract

A roller and mount assembly is disclosed for mounting on grassland maintenance apparatus. The assembly comprises at least one roller and mounting means for mounting the roller on the apparatus such that the rotational axis of the roller is arranged at a pre-determined angle Á to the direction of travel of the roller. <Figure 2>

Description

ROLLER AND MOUNT ASSEMBLIES The present invention relates to grassland maintenance apparatus such as agricultural mowing apparatus equipped with ground rollers and more particularly to roller and mount assemblies suitable for mounting on such grassland maintenance apparatus.

Conventional grassland maintenance apparatus is equipped with rollers set perpendicular to the direction of travel, such as a grass cutting apparatus fitted with a roller mounted to the front and rear of the apparatus.

During grass cutting, agricultural mowing apparatus is towed by a prime mover such as a tractor. As the mowing apparatus is pulled along the ground, debris such as grass and other material is compressed by the weight of the apparatus and the debris gathers on the respective cylindrical surfaces of the rollers. Attempts to remove debris are generally made by using cleaning wires/bars which run along the length of the rollers. The disadvantage of this system is that the wire/bar becomes clogged as grass is trapped between the surface of each roller and the respective wire/bar. Also problems arise due to the wire/bar arrangement being incorrectly set and therefore being ineffective.

It is an aim of the present invention to alleviate the disadvantages of the prior art by preventing the build-up of debris on ground rollers for mounting on grassland maintenance apparatus.

Accordingly, the present invention provides a roller and mount assembly for mounting on grassland maintenance apparatus of the type suitable for coupling to a prime mover, the assembly comprising at least one roller and mounting means for mounting the roller on the grassland maintenance apparatus such that the rotational axis of the roller is arranged at a pre-determined angle a to the axis defined by the direction of travel of the roller, said angle a being an angle other than 90°, whereby resistance to rotation by the roller results, thereby decreasing the rotational speed of the roller so that the rotational speed of the roller is slower than the forward speed of the roller, thereby creating a wiping action between roller surface and ground surface and preventing build up of material on the roller.

Preferably, the angle a between the rotational axis of the roller and axis defined by the direction of travel of the primary mover is less than 90 degrees.

Preferably, the roller is offset from the axis perpendicular to the direction of travel by an angle of between approximately 1 and 10 degrees, depending on the length of the roller and the ground speed of the apparatus (i.e. the angle a is between approximately 80 and 89 degrees).

Advantageously, the apparatus includes means for mounting the rollers such that the respective rotational axes of the rollers converge towards each other.

Advantageously, the assembly includes at least two rollers and the mounting means includes first mounting means for mounting the respective ends of the rollers at one side of the apparatus and second mounting means for mounting the respective ends of the rollers at the other side of the apparatus.

Ideally, the angle a for each roller is the same.

Ideally, each mounting means includes roller mounting means for rotatably mounting the roller onto the mounting means and connection means for connecting each mounting means to the grassland maintenance apparatus.

Preferably, in one of said first mounting means and said second mounting means, the vertical (longitudinal) axis of the roller mounting means is co-axial with the longitudinal axis of the connection means while in the other of said first and second mounting means the vertical (longitudinal) axis of the roller mounting means is parallel to the longitudinal axis of the connection means and offset therefrom by a predetermined distance.

Advantageously, the dimensions of the predetermined distance by which the respective longitudinal axes of the roller mounting means and the connection means are offset from each other, determines the size of the angle a.

IE0 207 15 Conveniently, one roller (second roller) may be located behind the other roller (first roller) or alternatively the two rollers may be located adjacent each other.

The present invention also provides a grassland maintenance apparatus having a roller and mount assembly in accordance with the invention mounted thereon.

The roller and mount assembly of the present invention will now be described more particularly by way of example only with reference the accompanying drawings in which are shown two embodiments of the assembly of the invention.

In the drawings: Figure 1 is a schematic plan of the conventional roller arrangement (Prior Art); Figure 2 is an underside perspective view of the assembly of the present invention in a first embodiment of the invention in which the rollers are shown mounted front and rear of a grass cutting apparatus; Figure 2(a) is a further underside perspective view as in Figure 2 but with the rollers mounted on foe grass cutting apparatus; Figure 3 is a detailed plan view of the assembly of the present invention; Figure 4a is a front view of the first mounting means; Figure 4b is a front view of the second mounting means; Figure 5 is a cross-sectional view through the roller; and Figure 6 is a plan view of the assembly in a second embodiment of the invention, in which both rollers are provided immediately adjacent each other, in a side by side arrangement.

Referring initially to Figure 1, the prior art roller arrangement is shown in which a mowing apparatus M includes a front ground roller FR and a rear ground roller RR. In use for cutting grass, when the mowing machine is being towed by a prime mover such as a tractor, the mowing machine rests on the rollers. The rollers follow the contours of uneven ground to ensure even cut length is obtained and to protect the ground by avoiding scalped areas where the cutting blades (not shown) of the mowing machine hit the ground. In the prior art arrangement shown in Figure 1, the rollers are mounted on the mowing machine parallel to each other and with the rotational axis (FR-RA) of the front roller FR and the rotational axis (RR-RA) of the rear roller RR, both being perpendicular to the axis defined by the direction of Travel (indicated by arrow T). As a result, the distance between the rotational axis (FR-RA) and the rotational axis (RR-RA) is the same at each side of the mowing machine M as shown in Figure 1.

Referring now to Figure 2 and Figure 3, the roller and mount assembly of the invention is indicated generally by reference number 1. The roller and mount assembly 1 is shown mounted on a mowing machine 2 and includes a front roller 3 and a rear roller 4. The front roller 3 and rear roller 4 are each mounted at one end, to the mowing machine 2, by first mounting means 30, 40 respectively and at their respective other end, by second mounting means 31, 41 respectively. The first mounting means 30 on roller 3 is the same in construction and operation as the first mounting means 40 on roller 4 and the second mounting means 31 on roller 3 is the same in construction and operation as the second mounting means 41 on roller 4.

Each mounting means 30,' 31; 40, 41 includes a spherical bearing 32, 33; 42, 43, respectively for mounting respective rollers 3, 4 to the mounting means 30, 31; 40, 41. There are also body mount arms 35, 36; 45,46 for connecting the mounting means 30, 31; 40, 41 respectively, to the body of a mowing apparatus. The body mount arms 35, 36, 45, 46 are each in the form of an internally threaded barrel fixed to the top of the mounting plate 50. A corresponding threaded bolt 38, 39; 48, 49 is fixedly attached to the mowing apparatus 2 for connection to the respective barrel.

There is also a height indicator probe 52 which is fixed to one side of the mounting plate 50. The height indicator probe 52 is part of a height adjustment mechanism which is described in applicants co-pending Irish application no. S72950 and United Kingdom Patent Application No. 2303287.

In the drawings, the direction of travel of the rollers when mounted on a mowing apparatus, for instance, being pulled by a prime mover, is indicated by arrow T. The rotational axis of the front roller 3 is indicated by the letter A and the rotational axis of the rear roller 4 is indicated by the letter B.

According to the invention, two types of roller mounting means are used on each roller 3,4 as shown on Figures 4a, 4b, namely the first mounting means 30, 40 and the second mounting means 31, 41. Each roller 3, 4 is fitted to each roller mounting means 30, 31; 40, 41 using a roller shaft bearing 32, 33; 42, 43 respectively, allowing each roller 3, 4 to rotate about its rotational axis at an angle to the direction of travel T.

The roller shaft bearings 32, 33; 42, 43 are generally spherical in profile and are secured to a bearing mount plate 50.

In first roller mounting means 30, 40, the roller mounting location is situated on the same vertical axis as the body mount arm 35,45 respectively as shown in Figure 4a.

In second roller mounting means 31, 41, the roller mounting location is offset a distance ‘C’ from the body mount arm 36, 46 respectively as shown in Figure 4b.

It is the distance C, that determines the angle a and thus determines the extent to which each roller rotational axis is offset from the perpendicular to the direction of travel T.

The first mounting means 30, 40 and the second mounting means 31,41 must be used on the same side of the mowing apparatus to ensure that the respective rotational axis of each roller 3,4 is converging towards each other as described above and shown on Figure 2 and Figure 3. Thus, first mounting means 30, 40 are both at one side of the mowing apparatus 2 and second mounting means 31,41 are both at the other side of the mowing apparatus 2. Figure 4a shows the first mounting means 30, 40 on one side of the mowing apparatus 2. In the first mounting means, the vertical axis indicated by the letter V of the body mount arm 35 coincides with the vertical axis of the spherical bearing 32 on which the roller 3 is mounted at one side of the mowing apparatus 2. The same arrangement applies for the vertical axis of the body mount arm 45 and the spherical bearing 42 on roller 4 at the same side of the mowing apparatus 2.

Figure 4b shows the second mounting means 31, 41 on the opposite side of the mowing apparatus 2. In the second mounting means, the vertical axis VI of the body mount arm 36 is parallel to and offset by a distance C from the vertical axis V2 of the spherical bearing 33 on which the roller 3 is mounted. Likewise, the arrangement shown in Figure 4b applies to spherical bearing 43 and body mount arm 46 for roller 4.

The manner of operation of the roller and mount assembly of the invention will now be described. To prevent material/debris accumulating on the roller surface and to remove built up material from the respective cylindrical surface of the rollers 3, 4, the rotational speed of the rollers must be either slower or faster than the ground speed at which the primary mover is travelling, thereby creating a wiping action between the ground and the rollers 3, 4. In the case of the roller and mount assembly of the present invention, the rotational speed of the rollers 3, 4 is slower that the forward speed of the mowing apparatus.

The rotational speed of the rollers 3, 4 is controlled by placing the rotational axis of the front roller at an angle a to the axis defined by the direction of travel T. In this arrangement, the front roller 3 attempts to find the path of least rotational resistance, which is that perpendicular to the roller axis, thereby drawing the machine over to one side. To counteract this action, the rear roller 4 is set at an equal angle a to the axis defined by the direction of travel T, but angled in the opposite direction i.e. the axis A, B of both rollers3, 4 respectively, must be set such that they are converging towards each other.

Each roller counteracts the lateral pull of the other roller and in use effectively, a rotational resistance reduces the speed of the rollers 3, 4 as a primary mover pulls the mowing apparatus.

Referring to Figure 5, the reduced rotational speed of the rollers is slower than the speed at which the mowing apparatus is travelling, thereby creating a wiping action between the roller surface and the ground surface.

Referring now to Figure 6, the second embodiment of the roller and mount assembly of the invention is shown. In the second embodiment, the second roller 4’ is mounted alongside the first roller 3’ rather than behind the first roller as in the first embodiment. The rollers 3’, 4’ are mounted on the mowing machine 2’ at an angle a to the axis defined by the direction of travel T. As in the first embodiment, the respective rotational axes of rollers 3’, 4’ are set such that they are converging towards each other.

The assembly in the second embodiment operates in the same way as described above in relation to the first embodiment.

The assembly of the invention has foe advantage that it provides self-cleaning rollers which prevent the build-up of matter accumulating on the rollers, without the use of scraper bars or wires, used on a vegetation maintenance moving machine and the like.

The embodiments of this invention described above are described in relation to agricultural mowing apparatus but it is to be understood that the roller and mount assembly of the invention can be used in conjunction with any grassland maintenance machinery.

It will of course be understood that the roller and mount assembly of the present invention is not limited to foe specific details described herein, which are given by way of example only and that various modifications and alternations are possible within the scope of the invention as defined in the appended claims.

Claims (5)

CLAIMS:

1. A roller and mount assembly for mounting on grassland maintenance apparatus of the type suitable for coupling to a prime mover, the assembly comprising at least one roller and mounting means for mounting the roller on the grassland maintenance apparatus such that the rotational axis of the roller is arranged at a pre-determined angle a to the axis defined by the direction of travel of the roller, said angle a being an angle other than 90°, whereby resistance to rotation by the roller results, thereby decreasing the rotational speed of the roller so that the rotational speed of the roller is slower than the forward speed of the roller, thereby creating a wiping action between roller surface and ground surface and preventing build up of material on the roller.

2. A roller and mount assembly as claimed in Claim 1, wherein the angle a between the rotational axis of the roller and axis defined by the direction of travel of the primary mover is less than 90 degrees; and optionally wherein the roller is offset from the axis perpendicular to the direction of travel by an angle of between approximately 1 and 10 degrees, depending on the length of the roller and the ground speed of the apparatus (i.e. the angle a is between approximately 80 and 89 degrees); and optionally wherein the apparatus includes means for mounting the rollers such that the respective rotational axes of the rollers converge towards each other.

3. A roller and mount assembly as claimed in Claim 1 or Claim 2, wherein the assembly includes at least two rollers and the mounting means includes first mounting means for mounting the respective ends of the rollers at one side of the apparatus and second mounting means for mounting the respective ends of the rollers at the other side of the apparatus; and optionally wherein the angle a for each roller is the same; and optionally wherein one roller is located behind the other roller; and optionally wherein the two rollers are located adjacent each other; and optionally wherein each mounting means includes roller mounting means for rotatably mounting the roller onto the mounting means and connection means for connecting each mounting means to the grassland maintenance apparatus; and optionally wherein in one of said first mounting means and said second mounting means, the vertical (longitudinal) axis of the roller mounting means is co-axial with the longitudinal axis of the connection means while in the other of said first and second mounting means the vertical (longitudinal) axis of the roller mounting means is parallel to the longitudinal axis of the connection means and offset therefrom by a predetermined distance; and optionally wherein the dimensions of said predetermined distance by which the respective longitudinal axes of the roller mounting means and the connection means are offset from each other, determines the size of the angle a.

4. A grassland maintenance apparatus having a roller and mount assembly as claimed in Claim 1, mounted thereon.

5. A roller and mount assembly, substantially as herein described with reference to and as shown in the accompanying drawings.