SE2250093A1

SE2250093A1 - Stop wheel for agricultural implement, row unit comprising such stop wheel, and agricultural implement

Info

Publication number: SE2250093A1
Application number: SE2250093A
Authority: SE
Inventors: Morgan Collin
Original assignee: Vaederstad Holding Ab
Priority date: 2022-02-01
Filing date: 2022-02-01
Publication date: 2023-08-02

Abstract

A stop wheel (26) for an agricultural implement comprises a hub portion (261), positioned at a radially innermost portion of the stop wheel, a tread portion (262), positioned at a radially outermost portion of the stop wheel, and a web portion (261), extending radially between the hub portion and the tread portion. The web portion presents a wavy profile, as seen in a sectional plane containing an axis (Ar) of rotation of the stop wheel.There is disclosed an output unit (2, 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h) comprising such a stop wheel and an agricultural implement (1) comprising a plurality of such output units (2, 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h).

Description

STOP WHEEL FOR AGRICULTURAL ll\/lPLEl\/IENT, ROW UNIT COl\/IPRISING SUCH STOP WHEEL, AND AGRICULTURAL ll\/lPLEl\/IENT Technical field The present disclosure relates to a stop wheel for use in an agricultural implement to receive a seed which is being output from a seed outlet and/or to press a deposited seed into contact with soil.

The disclosure also relates to a row unit comprising one or more such stop wheels and to an agricultural implement comprising one or more such row units.

Background Stop wheels, which may also be referred to as "press wheels" or "firming wheels", are used in agricultural implements, in particular planters, but also in some seeders or seed drills, to achieve at least one of two functions.

A first function is to press a deposited seed into proper contact with the surrounding soil. This is advantageous for the germination of the seed.

A second function is to, in particular in planters, to assist in receiving seed which are being propelled at high speed from a seed outlet towards the soil. ln particular, in some planters, the seed outlet is directed towards the area where a nip is formed between the stop wheel and the soil, such that seeds are immediately wedged between the stop wheel and the soil surface, to then immediately become pressed into contact with the soil as the implement advances. lt is desirable for stop wheels to be sufficiently firm to provide a proper compacting ofthe soil in a laterally limited area around the seeds, but yet to be able to yield some in the event of obstacles being encountered.

A stop wheel designed as illustrated in WO2020112015A1 has been found to meet the criteria discussed above.

However, under some circumstances, a stop wheel having spokes may be prone to attract and retain debris, such as plant residues and/or soil, which may impede the function of the stop wheel.

Hence, there is a need for a stop wheel having an improved design, and in particular a stop wheel which has a more reliable function.

Summary lt is an object of the present disclosure to provide an improved stop wheel, and in particular a stop wheel which has a more reliable function.

The invention is defined by the appended independent claims, with embodiments being set forth in the appended dependent claims, in the following description and in the attached drawings.

According to a first aspect, there is provided a stop wheel for an agricultural implement, comprising a hub portion, positioned at a radially innermost portion of the stop wheel, a tread portion, positioned at a radially outermost portion ofthe stop wheel, and a web portion, extending radially between the hub portion and the tread portion. The web portion presents a wavy profile, as seen in a sectional plane containing an axis of rotation ofthe stop wheel.

By providing the web portion with a wavy profile , the radial rigidity ofthe stop wheel can be reduced relative to a wheel having planar or slightly convex/concave web, while reducing the risk of debris getting stuck in the stop wheel to block the rotation ofthe stop wheel. The elastic movements ofthe tread portion relative to the hub portion will cause debris that has stuck to the waves to come off.

The web portion may have a substantially constant material thickness over at least 50 %, preferably at least 55 % or at least 60 %, of its radial extent.

The material thickness may be about 3-9 mm, preferably about 5-7 mm or about 6 mm.

The web portion may have an outwardly tapering material thickness over at least 50 %, preferably at least 55 % or at least 60 %, of its radial extent.

A minimum material thickness of the web portion may be about 75-95 % of a maximum material thickness. ln particular, the material thickness may taper from about 5-7 mm at its radially innermost portion to about 4-6 mm at its radially outermost portion.

The wavy profile may comprise a first wave top towards a first axial direction of the stop wheel and a second wave top towards a second, opposite, axial direction of the stop wheel.

The wavy profile may comprise at least one more wave top towards the first axial direction and/or at least one more wave top towards the second direction.

The first and second wave tops may be provided at different radia| distances from the axis of rotation.

An axial distance between the wave tops may be 50-150 %, preferably 75- 125 % or 90-100 %, of a maximum width of the stop wheel.

An axial amplitude ofthe waves may diminish in a direction radially outwardly from the hub portion.

The tread portion may have a radia| extent which corresponds to about 25-40 %, preferably about 30-35 %, of an outermost radius of the stop wheel.

The tread section may be substantially solid.

The tread portion may have a radia| extent which is about 4-6 cm, preferably about 4.5-5.5 cm.

The tread portion may have an axial extent which is about 2-4 cm, preferably about 2.5-3.5 cm.

The hub portion may have a radia| extent which is about 4-6 cm, preferably about 4.5-5.5 cm.

The hub portion may have an axial extent which is about 4-6 cm, preferably about 4.5-5.5 cm.

The stop wheel may have a radia| extent which is about 10-30 cm, preferably about 15-20 cm.

The hub portion may have a radia| extent which corresponds to about 15-25 % of an outermost radius ofthe stop wheel.

The web portion may have a radia| extent which corresponds to about 40-60 %, preferably about 45-55 %, of an outermost radius of the stop wheel.

The tread portion, the hub portion and the web portion may be formed of the same material, preferably in one piece of material.

The material may be a material presenting rubber elasticity, such as a rubber material or a rubber-like material.

The web portion may be formed as a substantially unbroken sheet of material having circumferentially extending waves.

According to a second aspect, there is provided an output unit for outputting granular material to ground over which the output unit travels, said output unit comprising a row unit frame, a material outlet for outputting said granular material, supported by the row unit frame, and a stop wheel as described above, supported by the row unit frame, wherein said stop wheel is arranged behind said material outlet, as seen in a working direction ofthe output unit.

The components ofthe row unit may be directly or indirectly supported by the row unit frame, e.g. in that the component may be positioned on a movable part of the row unit frame, so as to allow its position to be adjusted as desired.

According to a third aspect, there is provided an agricultural implement comprising frame, and a plurality of output units as described above, supported by said frame.

Drawings Figs 1a-1b schematically illustrate an agricultural implement in the form of a planter. Fig. 2 schematically illustrates a row unit.

Figs 3a-3d schematically illustrate a stop wheel.

Detailed description Figs 1a-1b show, in a perspective view obliquely from the front, respectively viewed from above, an agricultural implement 1 comprising an agricultural implement frame 10, which can comprise one or more beams 11, a coupling device 12, a control unit 13, a parking support 14 and a plurality of row units 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h (Fig 1b). The agricultural implement can be formed to be fully or partly supported, or pulled, by a traction vehicle (not shown), such as a tractor. ln the example shown, the row units 1 are mounted along a beam 11 which is transverse (perpendicular in the example shown) to a working direction F of an agricultural implement. ln the example shown, the agricultural implement has a fixed width and comprises eight row units. lt will be appreciated that the agricultural implement can have a variable width, so that its width can switch between a narrower transport mode and a wider working mode. For example, outer sections of the beam can be pivotable (for example about one or more vertical axes) or foldable, for example about one or more horizontal axes.

Each of the row units 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h may be mounted via an arrangement 15 for suspension/force limitation and/or for height adjustment (for example between the transport mode and the working mode). Such an arrangement may comprise a parallel linkage and a spring and/or hydraulic cylinder.

A row unit 1 will be described below. lt will be appreciated that in an agricultural implement 1 preferably, but not necessarily, a plurality of row units 2, 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h are identical and formed according to any ofthe embodiments described below. For example, a set of output units, such as row units, may comprise first and second units which are identical, albeit mirror inverted about a vertical plane comprising the working direction.

Fig. 2 schematically illustrates a row unit 2 for a planter. The row unit 2 may comprise a row unit frame 21, which may be connected to the frame 11 via the arrangement 15 for suspension/force limitation and/or for height adjustment.

The row unit 2 may further comprise a container 22 for material that is to be dispensed by the row unit 2. lt is noted that while some planter configurations use individual containers for each row unit, other planters feed each row unit from a central container for the planter. Yet further planters have individual containers which are replenished from a central container for the planter.

The row unit 2 may further comprise a metering device 23, which may be vacuum operated or pressure operated, and which operates to receive material from the container (or directly from a feed channel, as the case may be) and to output a controlled flow of singulated granules through a seed output 231.

A furrow opener 24 may comprise one or two furrow opener discs, as illustrated. Alternatively, the furrow opener may be provided in the form of a coulter or a seed knife, or the like.

The seed output may have an output opening arranged in or immediately behind, as seen in the working direction F, a seed knife. Alternatively, the seed output may have an output opening arranged between a pair of seed discs.

At least one gauge wheel 25 may be arranged for controlling an operating depth of the furrow opener 24 or seed knife. The gauge wheel(s) 25 may be rotatably supported on the row unit frame 21, or on a respective arm which may be movably connected to the row unit frame 21. The gauge wheel(s) 25 may be arranged to at least partially overlap the furrow opener, as illustrated. Alternatively, the gauge whee|(s) may be arranged behind or in front ofthe furrow opener 24.

A stop wheel 26 is arranged behind the seed outlet, as seen in the working direction F. The stop wheel will be further described with reference to figs 3a-3d.

For convenience ofthe description, an axial direction Da (fig. 3c) of the stop wheel 26 is defined as a direction extending along a geometric axis of rotation Ar of the stop wheel 26; a radia| direction Dr is defined as a direction which is perpendicular to the axial direction; and a central plane Pc is defined as a plane which is perpendicular to the axis of rotation and which extends through an axial center of a hub portion 261 of the stop wheel 26.

A furrow closer 27 may be arranged behind the stop wheel 26 as seen in the working direction. The furrow closer 27 may comprise one or more rotatably mounted wheels or discs. ln other embodiments, the furrow closer may comprises a tine or levelling tool.

Further tools may be provided as desired in front of, or behind, the other tools. For example, a row cleaner 28, as illustrated in fig. 2 may be provided in front of the furrow opener, e.g. to remove plant residues and thus to facilitate the planting operation. A straw harrow and/or a further reconsolidation device may be provided behind the other tools.

A stop wheel 26 will now be described with reference to figs 3a-3d.

The stop wheel 26 has a generally circular circumference and may be formed as an integrated part made of a rubber elastic material, such as rubber, one or more elastomers, or a polymeric material.

The stop wheel 26 comprises a hub portion 261, radially nearest a geometric axis of rotation Ar of the stop wheel 26, a tread portion 262, at a radially outermost portion of the stop wheel 26, and a web extending between 263, and connecting, the hub portion 261 and the tread portion 262.

The hub portion 261 may be formed essentially as a hub portion sleeve 2611 having a radia| extent and an axial extent. The hub portion 261 may be adapted for providing a rotatable connection of the stop wheel 26 to a supporting structure, such as the row unit frame 21.

The hub portion 261 may extend radially about 15-25 % of a maximum stop wheel radius.

The hub portion 261 may be provided with a sleeve insert 2612 that may be formed of a different material than the hub portion sleeve 2611. The sleeve insert may enclose a space 2613, which may be essentially cylindrical and adapted for connection to a bearing, such as a roller bearing (not shown).

For example, the sleeve insert 2612 may be formed of a polymeric material having greater rigidity than the material of the hub portion sleeve 2611 or of a metallic material.

The web portion 263 is formed radially outwardly of the hub portion.

The web portion 263 presents a wavy profile, as seen in a sectional plane containing the axis Ar of rotation of the stop wheel 26.

The web portion is formed of a body of material which may be relatively thin in the axial direction Da as compared with the hub portion 261 and the tread portion 262. For example, the web portion 263 may have a material thickness which is about 15-25 % of a greatest axial extent of the tread portion 262. ln particular, the material thickness may be about 3-9 mm, preferably about 5-7 mm or about 6 mm.

The material thickness may be substantially constant along over the web portion 263.

Alternatively, the material thickness of the web portion 263 may taper outwardly from the hub portion 261 towards the tread portion 262, except for any transition portion, as will be described later.

As seen in a cross section containing the axis Ar of rotation of the stop wheel 26, the web portion 263 presents a wavy profile. The wavy profile may comprise at least two waves 2632, 2633, 2634, 2635, which may be concentric about the axis Ar of rotation ofthe stop wheel 26.

The waves 2632, 2633, 2634, 2635 may be generally curved, as illustrated on the drawings. However, the principles of the present disclosure are applicable also to waves which are formed with other wave forms. For example, the waves 2632, 2633, 2634, 2635 may present themselves as generally triangular waves or as generally square waves, as seen in the cross section.

The web portion may be formed essentially as an unbroken sheet of material, i.e. with no significant through holes.

The web portion 263 may comprise one or more waves 2632, 2633, 2634, 2635, preferably an even number of waves, such as 2, 4 or 6.

For example, a first axial wave 2632 top may extend towards a first axial direction ofthe stop wheel 26 and a second axial wave 2633 top may extend towards a second axial direction of the stop wheel.

An absolute amount of an axial amplitude ofthe waves 2632, 2633, 2634, 2635 may diminish in the direction Dr radially outwardly.

For example, an axial amplitude ofthe first axial wave 2632 may be on the order of 65-90 %, preferably 70-80 %, of a maximum axial extent of the hub portion 261.

The tread portion may have a radial extent which is about 4-6 cm, preferably about 4.5-5.5 cm. I\/|oreover, the tread portion may have an axial extent which is about 2-4 cm, preferably about 2.5-3.5 cm.

The hub portion may have a radial extent which is about 4-6 cm, preferably about 4.5-5.5 cm. I\/|oreover, the hub portion may have an axial extent which is about 4-6 cm, preferably about 4.5-5.5 cm.

The stop wheel may have a radial extent which is about 10-30 cm, preferably about 15-20 cm.

Preferably, the axial extents of the hub portion and of the tread portion may be the same regardless of the radial extent of the stop wheel.

Also the radial extents ofthe hub portion and ofthe tread portion may be the same regardless ofthe radial extent ofthe stop wheel.

The second axial wave 2633 top may be positioned at a greater radial distance from the axis of rotation Ar than the first axial wave 2632 top.

An absolute amount of an axial amplitude from the central plane Pc of the second axial wave 2633 may be on the order of 80-95 %, preferably 85-90 %, of an axial amplitude of the first axial wave 2632, irrespective of the first axial wave's 2632 axial amplitude relative to the axial extent of the hub portion 261.

A radial distance between the first wave 2632 top and the second wave 2633 top may be on the order of 6-15 % of a total radius ofthe stop wheel 26, preferably about 8-12 %.

A third axial wave 2634 top may extend towards the first axial direction.

The third axial wave 2634 top may be positioned at a greater radial distance from the axis of rotation than the second axial wave 2633 top.

An absolute amount of an axial amplitude from the central plane Pc of the third axial wave 2634 may be on the order of 90-99 %, preferably 93-97 %, of an axial amplitude ofthe second axial wave 2633, irrespective of the second axial wave's 2633 axial amplitude relative to the axial amplitude of the first axial wave 2632.

A radial distance between the second wave 2633 top and the third wave 2634 top may be on the order of 6-15 % of a total radius of the stop wheel 26, preferably about 8-12 %.

A fourth axial wave 2635 top may extend towards the second axial direction.

The fourth axial wave 2635 top may be positioned at a greater radial distance from the axis of rotation than the third axial wave 2534 top.

An absolute amount of an axial amplitude from the central plane Pc of the fourth axial wave 2635 may be on the order of 45-65 %, preferably 50-60 %, of an axial amplitude ofthe third axial wave 2634, irrespective ofthe third axial wave's 2634 axial amplitude relative to the axial amplitude of the second axial wave 2633.

A radial distance between the third wave 2634 top and the fourth wave 2635 top may be on the order of 6-15 % of a total radius ofthe stop wheel 26, preferably about 8-12 %.

The first and third axial wave 2632, 2634 tops may be located at a first axial side ofthe central plane Pc ofthe stop wheel 26. The second and fourth axial wave 2633, 2635 tops may be located at a second axial side of the central plane Pc.

The web portion 263 may comprise a hub transition portion 2631, at which a material thickness of the web portion 263 increases in a direction generally radially inwardly relative to the material thickness of the web 263. Where the web has an outwardly tapering material thickness, the hub transition portion may exhibit a taper rate that is greater than a taper rate ofthe web portion.

The web portion 263 may comprise a tread transition portion 2636, at which a material thickness ofthe web increases in a direction generally outwardly, preferably continuously, so as to transition to the tread portion 262.

The tread portion 262 may be formed as a generally annular body 2621 having an inner portion 2623 with an axial extent that is 3-6 times greater than the material thickness of the web portion. The tread portion 262, in particular the inner portion 2623, may have a maximum axial extent which may be on the order of 60-80 %, preferably 65-75 % ofthe maximum axial extent of the hub portion 261.

From the inner portion 2623, the axial extent ofthe tread portion 262 may taper in a direction radially outwardly, where it may transition to a tread surface 2622.

Thetreadsuﬁace2622rnayberadmﬂyouhmanﬂyﬂatorconvex.Anaxml extent ofthe tread surface 2622 may be on the order of 40-60 % of the axial extent of the radially inner portion 2623 of the tread portion 262.

Claims

1. A stop wheel (26) for an agricultural implement, comprising: a hub portion (261), positioned at a radially innermost portion of the stop wheel, a tread portion (262), positioned at a radially outermost portion of the stop wheel, and a web portion (261), extending radially between the hub portion and the tread portion, characterized in that the web portion (261) presents a wavy profile, as seen in a sectional plane containing an axis (Ar) of rotation ofthe stop wheel.

2. The stop wheel as claimed in claim 1, wherein the web portion (263) has a substantially constant material thickness over at least 50 %, preferably at least 55 % or at least 60 %, of its radial extent.

3. The stop wheel as claimed in claim 2, wherein the material thickness is about 3-9 mm, preferably about 5-7 mm or about 6 mm.

4. The stop wheel as claimed in claim 1, wherein the web portion (263) has an outwardly tapering material thickness over at least 50 %, preferably at least 55 % or at least 60 %, of its radial extent.

5. The stop wheel as claimed in claim 4, wherein a minimum material thickness is about 75-95 % of a maximum material thickness.

6. The stop wheel as claimed in any one ofthe preceding claims, wherein the wavy profile comprises a first wave (2632) having a wave top towards a first axial direction of the stop wheel and a second wave (2633) having a wave top towards a second, opposite, axial direction (Da) ofthe stop wheel.

7. The stop wheel as claimed in claim 6, wherein said first and second wave tops are provided at different radia| distances from the axis of rotation (Ar).

8. The stop wheel as claimed in claim 6 or 7, wherein an axial distance between the wave tops is 50-150 %, preferably 75-125 % or 90-100 % of a maximum width of the stop wheel.

9. The stop wheel as claimed in any one of claims 6-8, wherein an axial amplitude ofthe waves (2632, 2633, 2634, 2635) diminishes in a direction radially outwardly from the hub portion (261).

10. The stop wheel as claimed in any one ofthe preceding claims, wherein the tread portion (262) has a radia| extent which corresponds to about 25- 40 %, preferably about 30-35 %, of an outermost radius of the stop wheel.

11. The stop wheel as claimed in any one ofthe preceding claims, wherein the tread portion (262) is substantia||y solid.

12. The stop wheel as claimed in any one ofthe preceding claims, wherein the tread portion (262) has a radia| extent which is about 4-6 cm, preferably about 4.5-5.5 cm.

13. The stop wheel as claimed in any one ofthe preceding claims, wherein the tread portion (262) has an axial extent which is about 2-4 cm, preferably about 2.5-3.5 cm.

14. The stop wheel as claimed in any one ofthe preceding claims, wherein the hub portion (261) has a radia| extent which is about 4-6 cm, preferably about 4.5-5.5 cm.

15. The stop wheel as claimed in any one ofthe preceding claims, wherein the hub portion (261) has an axial extent which is about 4-6 cm, preferably about 4.5-5.5 cm.

16. The stop wheel as claimed in any one ofthe preceding claims, wherein the stop wheel (26) has a radial extent which is about 10-30 cm, preferably about 15-20 cm.

17. The stop wheel as claimed in any one ofthe preceding claims, wherein the hub portion (261) has a radial extent which corresponds to about 15-% of an outermost radius ofthe stop wheel (26).

18. The stop wheel as claimed in any one ofthe preceding claims, wherein the web portion (263) has a radial extent which corresponds to about 40-%, preferably about 45-55 %, of an outermost radius of the stop wheel (26).

19. The stop wheel as claimed in any one ofthe preceding claims, wherein the tread portion (262), the hub portion (261) and the web portion (263) are formed of the same material, preferably in one piece of material.

20. The stop wheel as claimed in any one ofthe preceding claims, wherein the material is a material presenting rubber elasticity, such as a rubber material or a rubber-like material.

21. The stop wheel as claimed in any one ofthe preceding claims, wherein the web portion (263) is formed as a substantially unbroken sheet of material having circumferentially extending waves (2632, 2633, 2634, 2635).

22. An output unit (2, 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h) for outputting granular material to ground over which the output unit travels, said output unit comprising: a row unit frame (21), a material outlet (231) for outputting said granular material, supported by the row unit frame (21), and a stop wheel (26) as claimed in any one ofthe preceding claims, supported by the row unit frame (21), wherein said stop wheel (21) is arranged behind said material outlet (231), as seen in a working direction (Dw) ofthe output unit (2, 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h).

23. An agricultural implement (1) comprising: a frame (11), and a plurality of output units (2, 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h) as claimed in claim 5 22, supported by said frame (11).