WO2010120166A1

WO2010120166A1 - Aerator device for lawns with vibrating tines

Info

Publication number: WO2010120166A1
Application number: PCT/NL2009/000094
Authority: WO
Inventors: Marinus Reicke
Original assignee: Marinus Reicke
Priority date: 2009-04-14
Filing date: 2009-04-14
Publication date: 2010-10-21

Abstract

The invention compromises a chassis (21) which includes a main driven shaft (3) in the horizontal plane, across the drive direction. On this shaft, eccentric cams (17) are mounted in a fixed sequence. Around these cams, disc assemblies (6-11) can freely rotate, due to the bearings (18) in-between. On the discs (19) of the disc assemblies (6-11), different kind of tines (14) can be mounted. When the device is on the ground and moved forwards, the disc assemblies with the tines unroll over the ground and penetrate the soil by the machine weight. If next the main shaft (3) is driven, the disc assemblies (6-11) with the tines (14) get an additional vibration action in the length direction of the tines. This vibration makes that the penetration of the tine is easier and cleaner. If these tines (14) are hollow tines which collect soil inside, the soil is shaken out during exiting the soil. The soil is loose, which is a perfect place for the adjacent grass roots to grow into. The remaining, not usable part of the core will be dropped on top of the lawn and can be collected later.

Description

AERATOR DEVICE FOR LAWNS WITH VIBRATING TINES.

The invention pertains to a device for aerating lawns, compromising:

- a chassis, - a connecting system, to move the device across the ground,

- a driven main shaft in the horizontal plane, mounted with bearings in the chassis, square to the forward movement of the device,

- eccentric cams, mounted on the driven main shaft,

- at least two discs assemblies, mounted with bearings around the eccentric cams on the main drive shaft, aerator tines mounted on a disc of the disc assemblies, with the characteristic that, the aerator tines, during unrolling over the lawn, are charged with a vibration in the length direction of the aerator tines.

Lawns and other grass fields get compacted due to the use and environmental reasons. Due to this compaction, oxygen cannot enter the soil anymore. The soil will sour and the correct soil balance will be disturbed.

Aerating is an important treatment for a well maintained lawn. There are many kinds of aerating machines. If we limit ourselves to aerating machines with tines, we can roughly divide them in two categories: Aerator machines with solid tines and with hollow tines. The ones with hollow tines removes material from the soil. These removed cylindrical bars are called cores and can be collected and removed.

To optimize the aerating process, the holes should be refilled with soil. Sometimes the existing soil from the cores is used, after they have been crunched. The grass roots like this ( new) soil and will grow better. In practice, it is hard to fill the holes from the top till the bottom. Often the new material

"bridges" itself in the channel of the hole, when they try to fill it from the top.

Existing hollow tine aerators make a full stroke, which means that the core is taken out in one piece. The top part of the core consists of turf, which cannot be used and needs to be removed.

The soil underneath can often be re-used. But if everything is taken out in one stroke, it is hard to split, so often the complete core is removed and new material is used to fill the holes. This is an expensive and time consuming job, as all cores have to be removed and disposed and new soil has to be bought and put in the holes.

The invention claims to solve this problem, as the hollow tine vibrates in length direction during plugging the core. First this vibration makes that the tine goes easier in the soil and next during withdrawal of the tine, the soil is shaken out of the core. This shaken soil stays at the bottom of the hole. Since this soil is de-compacted and at the bottom of the hole, the roots of the grass can embed themselves easily in this soil. Less core material has to be removed and less new material has to be added. The invention is to be described by means of the non- exhaustive operation example, represented in the following figures, where: figure 1 is a perspective, partly cut-away side view of the aerator device, according to a preliminary operation model of the invention, figure 2 is a schematic cross section of figure 1, figure 3 is a schematic detailed view of the tine disc, equipped with hollow tines, who cut a core and shake the soil out, figure 4 is a schematic top cross section of fig. 2.

Figure 1 gives a perspective view of the aerator device. The device compromises a main chassis (21) with a non-limitative mounting clamp (4,23), which is used to mount the device to a driving vehicle. The device is available in different configuration, which can be adapted to different types of driving vehicles.

The chassis (21) is supported by support roller (5), which controls the depth setting of the tines. This depth is adjustable. The driven main shaft (3) is mounted with bearings in the main chassis (21) in the horizontal plane and square to the forward motion (20) of the device. This driven main shaft is driven by drive means (1, 2 and 22).

Around this main driven shaft (3) a couple of tine disc assemblies (6 - 11) are mounted on the eccentric cams (17) with bearings (18) in-between. The disc assemblies are mounted in certain timed sequence.

The tine disc assemblies compromise base discs (19) on which different kind of tines (12) can be mounted. In this example, the tine disc assembly has two base discs (19). At the moment the tines are in contact with the lawn and the device (21) is pulled forward (20), the tine disc assemblies (6-11) will roll over the lawn. Due to the weight of the device, the tines will enter the lawn. The depth is limited by the setting of the support roller (5), or the balance between the weight of the device and the resistance of the tines in the soil At the moment, that the main shaft (3) is driven by means (1, 2 and 22), the tine disc assemblies ( 6 - 11) will start to vibrate. This vibration creates a up and down movement of the tine (14), in its length direction, who is further guided in the soil. The frequency of the vibration is set by the revolutions of the main drive shaft (16), while the amplitude is set by the size of the eccentric cam (17).

Figure 2 shows a cross section from the side, showing one of the tine disc assembly (6-11). This figure also shows that, if there is no vibration, it will be hard to push the tines in the soil by weight only. The weight G from the aerator device works vertically down. Tine 12c will be pushed into the soil. However tines 12a, 12b, 12d and 12e cannot be pushed vertically down. They have to be pushed in the length direction, which is not happening by the weight G. With other words, tines 12a, 12b, 12d and 12e are preventing tine 12c to penetrate any deeper, as the weight G is carried by the areas (30) from the other tines. The invention solves this problem too. Because the vibration of the tines in the length direction of the tines ( 12a -12e), pushes every tine in its length direction (14 in fig 1, 3) during the time they are in the soil.

Figure 3 shows the details when the hollow tines unrolls (13) over the lawn. When the main shaft 3 is driven, the tine disc assembly (6- 11) moves in the length direction of the tines (14). Hollow tine 12a is starting to enter the soil. Tine 12 is pushed further in the soil (12a-> 12b-> 12c), when the disc assembly (6-11) unrolls further along the lawn surface. The penetration is made easier with the help of the vibration (14).

A hollow tine is always tapered, meaning that the diameter at the start point is a little less. Due to this relief, the core will not stick inside the hollow tine. The core has to exit at the other side of the hollow tine.

At the moment the hollow tine (12) has reached its maximum depth (12c), it will exit the soil via 12c -> 12d -> 12e. During this period, the hollow tine (12) is still shaking in its length direction. This shaking action is also applied to the core, that is inside the hollow tine and makes that the soil around the roots from the grass is released and put back in the hole just made (43, 44) This soil is loose, which reduces the overall compaction of the soil and which also is a perfect place for the roots of the adjacent grass.

At existing hollow tine aerators, sometimes the core sticks inside the hollow tine, because the relief angle is not correct and/ or the hollow tine makes only one stroke. The vibration action at the invention helps to prevent this as well, since the vibration prevents the core sticking inside the hollow tine.

The remaining material of the core (46- 46a- 46b), which is still in the hollow tine 12, will be released at the moment the tine disc assembly (6-11) rotates further along the lawn and the hollow tine is up-site-down (12f, fig 2). This material can be collected separately. But since some of the soil has been brought back in the holes, less material has to be disposed. Figure 4 shows a cross top section view. Main shaft (3) is mounted with two bearings (51, 52) into the main chassis (21). The main shaft is driven by means (2). The eccentric cams (17) are mounted on the main shaft (3) in a fixed timed pattern for a perfect balance during the work. The invention uses mechanically evoked vibrations. This can also be done by other means.

Claims

CLAIMS.

1. The invention pertains to a device for aerating lawns, compromising: a chassis, - a connecting system, to move the device across the ground, a driven main shaft in the horizontal plane, mounted with bearings in the chassis, square to the forward movement of the device,

- eccentric cams, mounted on the driven main shaft,

- at least two discs assemblies, mounted with bearings around the eccentric cams on the main drive shaft,

- aerator tines mounted on a disc of the disc assemblies, with the characteristic that, the aerator tines, during unrolling over the lawn, are charged with a vibration in the length direction of the aerator tines.

2. Device according to claim 1, with the characteristic that, in case the aerator tine is solid, the vibration action makes that this tine goes easier in the soil and creates less damages around the hole edge, when exiting the soil.

3. Device according to claim 1, with the characteristic that, in case the aerator tine is a hollow tine, the vibration makes that the tine goes much easier in the soil and that during exiting the soil the usable soil is shaken out of the core and left in the hole.

4. Device according to claim 3, with the characteristic that, due to the vibration the core inside the tine, moves easier through the hollow tine, without adhering.

5. Device according to claim 1-3, with the characteristic that, the tines are exchangeable.

6. Device according to claim 1, with the characteristic that the penetration power of the tines is related to the forward speed of the device.

7. Device according to claim 1, with the characteristic that the eccentric mounted cams on the main shaft are at a fixed timed pattern.

8. Device according to claim 1, with the characteristic that the size of the amplitude of the cam can be changed.

9. Device according claim 1, with the characteristic that the frequency of the vibration can be changed.

10. Device according to claim 3, with the characteristic that the removed core can be caught and/ or collected into a not further described collecting device.