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EP-4434323-B1 - BALER AND METHOD OF BINDING A BALE

EP4434323B1EP 4434323 B1EP4434323 B1EP 4434323B1EP-4434323-B1

Inventors

  • HOL, Jan Johannes Judocus

Dates

Publication Date
20260506
Application Date
20240313

Claims (13)

  1. A baler comprising a bale forming chamber (26), a reciprocating plunger (30) configured to compress bale material in the bale forming channel to form a bale (B) and a binding system for binding the bale (B) in a bale forming channel of a baler with a pair of twines (64,66) that pass around opposite sides of the bale, the binding system including: a knotter (40) including a rotary bill hook (82) having a rotational axis (84), a twine holder (86), a twine cutter (94) and a stripper element (92) arranged to remove at least some knots from the bill hook (82); wherein the binding system is configured to tie a first knot and a second knot successively in the twines during one full operating cycle of the binding system, at least the second knot is a loop knot, wherein the bill hook (82) is rotatable between a first position in which the bill hook (82) engages the twines and a second position in which a knot formed by the knotter (40) is stripped from the bill hook (82) by the stripper element (92); the twine holder (86) comprising a first rotary disk (86a) including a first clamping notch (87b) arranged to receive the twines (64,66) during formation of the first knot, and a second clamping notch (87a) arranged to receive the twines during formation of the second knot, a retainer (120) positioned adjacent a periphery of the first rotary disk (86a) arranged to cooperate with the first rotary disk (86a) to hold the twines at least during a part of the operating cycle, a clamping plate (122) arranged to cooperate with the retainer (120) to hold the twines (64,66), at least until the second knot is stripped off by the stripper element (92), wherein the binding system includes a drive system for rotating the first rotary disk (86a) to clamp the twines (64,66) in one of the first and second notches (87a,87b) against the retainer (120) and/or clamping plate (122), wherein the retainer (120) and/or clamping plate (122), at least during the stripping off of the knots by the stripper element (92), is arranged to apply a greater clamping force on the twines (64,66) in a condition wherein the twines (64,66) are located in the first clamping notch (87b) than the clamping force applied on the twines (64,66) in a condition wherein the twines are located in the second clamping notch (87a); wherein at least part of the clamping plate (122) includes a curved outer surface, in a condition wherein the twines (64,66) are located in the second notch (87b), the first rotary disk (86a) is arranged to rotate the twines (64,66) beyond the curved outer surface, thereby releasing the twines (64,66) from the grip of the clamping plate (122) and the retainer (120; the curved outer surface comprises an arc having a radius (Rp) that extends from a rotation axis (126) of the first rotary disk (86a); wherein the radius (Rp) defining the arc of the outer surface of the clamping plate (122) has a radial distance that is less than or equal to a radial distance (Rb) from the rotation axis (126) of the first rotary disk to the innermost part of the first notch (87b); and/or the radius (Rp) defining the arc of the outer surface of the clamping plate (122) has a radial distance that is greater than the radial distance (Ra) from the rotation axis (126) of the first rotary disk to the innermost part of the second notch (87a).
  2. The baler of claim 1, wherein the depth of the second clamping notch (87a), relative to an outer circumference of the first rotary disk (86), is greater than the depth of the first clamping notch (87b).
  3. The baler of claim 1 or 2, wherein the twine holder (86) includes a second rotary disk (86b), the second rotary disk (86b) is fixed for rotation with the first rotary disk (86a) about a rotation axis (126), the second rotary disk (86b) includes a first clamping notch (87b') and a second clamping notch (87a'), and the clamping plate (122) is arranged to cooperate with the retainer (120) to hold the twines (64,66) located in one of the notches (87a',87b') of the second rotary disk (86b).
  4. The baler of claim 3, wherein the first and second rotary disks (86a,86b) are fixed to one another such that at least one first notch (87b) in the first rotary disk (86a) is rotationally aligned with at least one first notch (87b') in the second rotary disk (86b) and such that at least one second notch (87a) in the first rotary disk (86a) is rotationally aligned with at least one second notch (87a') in the second rotary disk (86b).
  5. The baler of claim 3 or 4, wherein the clamping plate (122) is positioned between the first and second rotary disks (86a,86b).
  6. The baler of any one of the preceding claims, wherein the first rotary disk (86a) is arranged to rotate relative to the clamping plate (122).
  7. The baler of any one of the preceding claims, wherein the retainer (122) is resiliently biased towards the center (126) of the first rotary disk (86a).
  8. The baler of any one of the preceding claims, wherein in a condition wherein the twines (64,66) are located in the second notch (87a) of the first rotary disk (86a), and the second knot is being stripped off by the stripper element (92), the first rotary disk (86a) is arranged to rotate the twines (64,66) beyond an end of the clamping plate (122), thereby releasing the twines (64,66) from the grip of the clamping plate (122) and the retainer (120).
  9. The baler of any one of the preceding claims, wherein rotation of the second notch (87a) beyond an end of the clamping plate (122) and / or beyond the curved outer surface is achieved by locating an additional gear stretch on a drive disk (76) after a gear stretch (105) for operating the first rotary disk (86a).
  10. The baler according to any one of the preceding claims, wherein the clamping plate (122) is pivotally attached (122a) to a mounting and is arranged to pivot with respect to the first rotary disk (86a) to a position wherein the twines (64,66) are released from the twine holder (86).
  11. The baler according to claim 10, wherein the twine holder (86) includes an actuation formation (200,210) that is arranged to actuate the clamping plate (122) thereby causing the clamping plate (122) to pivot to the position wherein the twines (64) are released from the twine holder (66).
  12. A method for binding a bale in a baler, the method including: providing a baler according to any one of the preceding claims; tying a first knot and a second knot successively in the twines (64,66) during one full operating cycle of the binding system, including: when forming the first knot, locating the twines in the first clamping notch (87b); clamping the twines (64,66) between the retainer (120) and the clamping member (122); the rotary bill hook (82) tying a first knot in the twines (64,66); the cutter (94) cutting the twines (64,66); when forming the second knot, locating the twines (64,66) in the second clamping notch (87a); the drive system rotating the first rotary disk (86a) to clamp twines (64,66), the retainer (120) clamping the twines (64,66) to the curved outer surface of the clamping member (122) as the twines move over the curved surface of the clamping member; the bill hook (82) tying a second knot wherein the second knot is a loop knot; the retainer (120) releasing the twines (64,66), or at least significantly reducing the clamping force applied to the twines (64,66), towards the end of the second knot forming cycle as the twines (64,66) pass an end of the clamping member (122) and/or an end of the curved surface of the clamping member (122), thereby preventing the twine cutter (94) from cutting the twines.
  13. The method of claim 12, wherein the stripping element (92) includes a screen (121); and the method further includes locating twine on the screen (121) in a first position when forming the first knot; and locating twine on the screen (121) in a second position when forming the second knot.

Description

The present invention relates to a baler and a method of binding a bale. The invention also relates to a baler comprising a bale forming channel, a reciprocating plunger and a binding system for binding a bale in the bale forming channel. It is known to provide a baler for pressing bales with a reciprocal plunger, whereby the bale is bound by tying a plurality of twine loops around the bale. The twine for binding the bale is supplied by two supplies per twine loop, one for the top side and one for bottom side of the bale. The closing of the loop around the finished bale is done by tying two knots. The basic principle of such a bale binding system is well described in US4074623 and EP1584227. US4074623 is an example of a binding system as described above in which the twines are tied with a conventional knot. EP1584227 is an example of a binding system as described above in which the twines of the second knot are tied with a loop knot so as not to have loose twine ends cut from the strands between the first and second knot. The binding of the bale is necessary to hold the bale under compression; the expansion of the bale as it is ejected from the baling channel puts a lot of tension on the binding twine. The breaking resistance of the binding twine and the knot(s) in the twine determine the maximum possible compression of the material in the bale. A high compression is desirable as the higher the compression the more efficiently the bale material can be stored and transported. EP1584227 suggests solutions for releasing the twine strands before the cutting of the second knot to form a loop knot as a second knot. The solutions suggested are complicated and not sufficiently reliable with different twine strengths and brands and will require many changes to the actual knotter design and are therefore not retrofittable on an existing knotter. Another baler comprising a knotter system is known from EP2908618, which discloses forming two consecutive knots, wherein the second knot is a loop knot. To form those knots, the strands are held in notches in a rotating twine disc by a retainer, and drive means are adapted for rotating the twine disc during a first turn whilst clamping twines for forming the first knot, and for rotating the twine disc during a second turn whilst letting twines slip for forming the second knot. The twine receiver is provided with biasing means for setting a bias for the clamping action by the twine holder. The biasing means are adapted to set a first bias during the first turn, and a second bias during the second turn. The first bias is chosen such that the twines are firmly clamped , while the second bias is chosen such that the twines are allowed to slip out of the twine receiver. It is an object of the present invention to provide a solution to one or more of the problems set out above, thereby allowing the compression of the bale to be increased without causing the twine loops to break and/or avoiding or mitigating one or more of the disadvantages of the system described in EP1584227. According to the present invention there are provided a binding system for a baler, a baler that includes a binding system, and a method for binding a bale as defined by the claims. According to the invention there is provided a baler according to claim 1. The invention enables a bale to bound in a manner such that at least the second knot comprises a loop knot, which enables compression of the bale to be increased without causing the twine loops to break, by providing a relatively simple mechanical solution that reliably produces loop knots. In some embodiments, the depth of the second clamping notch, relative to an outer circumference of the first rotary disk, is greater than the depth of the first clamping notch. The twine holder can include a second rotary disk. The second rotary disk can be fixed for rotation with the first rotary disk about a rotation axis. The second rotary disk can include a first clamping notch. The second rotary disk can include a second clamping notch. The clamping plate can be arranged to cooperate with the retainer to hold the twines located in one of the notches of the second rotary disk. The notch in which the twines are located being determined by the operational condition of the binding system. During formation of the first knot the twines are located in the first clamping notch of the first rotary disk, and optionally are located in the first clamping notch of the second rotary disk. During formation of the second knot the twines are located in the second clamping notch of the first rotary disk, and optionally are located in the second clamping notch of the second rotary disk. The first rotary disk can include a plurality of first clamping notches. The first rotary disk can include a plurality of second clamping notches. The first and second notches can alternate around the periphery of the first rotary disk. The second rotary disk can include a plurality of first clamping