Abstract:
A web wrap apparatus is provided having a separator with a separating edge and a feeder transporting web to a bale chamber. In order to keep the separating edge free of dirt, web fibers, etc. a stripper is connected to the feeder, which during a relative movement with respect to the separator strips along the separating edge and removes any particles sticking thereto.

Description:
FIELD OF THE INVENTION 
       [0001]    This invention relates to a web wrap apparatus with a feeder and a separator provided with a separating edge, the feeder and the separator being moveable relative to one another. 
       BACKGROUND OF THE INVENTION 
       [0002]    EP 766 912 discloses a round baler having a net feed device, moveable between a waiting position and a feeding position and a knife for the net. 
         [0003]    The problem this invention is based on is seen in the fact, that occasionally fibers of the net or other material build up on the edge of the knife and prevent a clean cut of the net. 
       SUMMARY OF THE INVENTION 
       [0004]    By using a stripper according to the invention, fibers or any other material sticking or hanging on the separating edge are removed. Dimensions, location, the way the stripper is fixed, etc. can be selected such, that a stripping action is performed depending on the expected dirt to be removed. The stripper could be attached to the feeder in a fixed or moveable way under a bias. 
         [0005]    Tolerances need not be too tight, if the stripper is elastic and flexible and will flex when it hits the separating edge and stays in close contact. While plastic and rubber are preferred, sheet metal or even wood would work as well. 
         [0006]    A brush of Nylon fibers or the like working as a stripper has the advantage of being highly flexible and thus insensitive to varying dimensions, and would also have a stronger cleaning effect, since a brush consists of a multitude of strippers. 
         [0007]    Since dirt, fibers, etc. sometimes are not easy to remove, a wiping movement in different directions may be more effective. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    The preferred embodiments of the invention are described in detail below with reference to the accompanying drawings wherein: 
           [0009]      FIG. 1  is a round baler in schematic side view provided with a web wrap apparatus; 
           [0010]      FIG. 2  is the web wrap apparatus of  FIG. 1  depicted in a waiting position; 
           [0011]      FIG. 3  is the web wrap apparatus of  FIG. 1  depicted in an intermediate position; 
           [0012]      FIG. 4  is the web wrap apparatus of  FIG. 1  depicted in a feeding position; 
           [0013]      FIG. 5  is the web wrap apparatus of  FIG. 1  depicted in a partly retracted position; 
           [0014]      FIG. 6  is the web wrap apparatus of  FIG. 1  depicted in a fully retracted position; 
           [0015]      FIG. 7  is a feeder with a stripper and a separator close to one another in side view; and 
           [0016]      FIG. 8  is the feeder and separator of  FIG. 7  in perspective view. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0017]      FIG. 1  shows a round baler  10 , which has a chassis  12 , a pick-up  14 , a bale chamber  16 , a web wrap apparatus  18 , an axle with wheels  20 , a tongue  22  and pressing elements  24 . 
         [0018]    The round baler  10  is of ordinary kind in a fix chamber version, but could also be a variable chamber baler. 
         [0019]    The chassis  12  rests on the axle with the wheels  20 , carries the pick-up  14  and can be connected to a tractor or the like by way of the tongue  22 . The chassis  12  has one or multiple part side walls  26 , which are spaced apart from one another to receive between them the bale chamber  16 , all or part of the web wrap apparatus  18  and the pressing elements  24 . 
         [0020]    The pick-up  14  picks up crop from the ground and delivers it to the bale chamber  16  through a crop inlet  28  between the pressing elements  24 . 
         [0021]    The bale chamber  16  is covered substantially by the pressing elements  24  on the circumference and by the side walls  26  on the face side. Beside the crop inlet  28  a gap  30  is provided between the pressing elements  24 , through which the web  32  may be fed into the bale chamber  16 . The bale chamber  16  serves to form a cylindrical bale of hay, straw or the like, which will be covered by the web  32  of plastic, net, paper or similar material. The pressing elements  24  in this embodiment are in the form of steel rolls rotatably received in the sidewalls  26  and extending perpendicular to them. These pressing elements  24  are substantially arranged on a circle. 
         [0022]    The web wrap apparatus  18  is visible in more detail in  FIG. 2  and contains among other things a housing  34 , a motion element  36 , a brake device  38 , a feeder  40 , a separator  42  and an actuating mechanism  44 . 
         [0023]    The housing  34  is located in the front upper part of the round baler  10  between or substantially between the side walls  26  and has a rear wall  46  and a left and a right wall  48  connected to one another and suitable to be connected to the side walls  26 . 
         [0024]    Depending on the width of the web  32 , the housing  34  and the entire web wrap apparatus  18  may extend beyond the side walls  26 . The rear wall  46  may be of a material or may have a layer which creates a certain friction, which will have an influence on the rolling resistance of a roll  50  of the web  32 . The housing  34  may be used to attach all components and parts of the web wrap apparatus  18  to it to form an autonomous unit. The right and left walls  48  extend to the rear towards the bale chamber  16  as is needed to take up some of the parts described later. 
         [0025]    The motion element  36  is formed by a roll  52 , preferably rubber coated, which is journalled rotatably about a horizontal axis in the walls  48  and which is located such, that the roll  50  of the web  32  can rest on it. At least with one end portion, the roll  52  extends beyond the walls  48  and possibly even beyond the side walls  26  and is provided with a yieldable clutch  54 , which may be a slip clutch, a rubber block between a flange and the roll  52  or the like. The clutch  54  has several—in this case three—actuators  56  evenly distributed on the circumference of a disc rotating with it; yet one would be sufficient. The actuators  56  may be stops, noses, or the like protruding radially, but it may also be grooves or notches in the circumference. When viewing the drawing, the roll  52  has about the same diameter as the clutch  54 . As is known, but not shown here, the roll  52  is connected via a chain drive and a free-wheel to the pressing elements  24  such, that it must rotate slower than the pressing elements  24 . 
         [0026]    The brake device  38  substantially has a control arm  58  and a brake arm  60  connected together by a shaft  62  to pivot about a horizontal axis of the latter. Also a gas spring  64  is connected to the shaft  62  via an arm  66  to assist or resist its rotational movement. It is the purpose of the brake device  38  to exert a certain pressure on the roll  50  of the web  32  to assure a sufficient tension in it, when it is wrapped onto a bale (not shown). The shaft  62  is located at about the same height as the roll  52  and at a certain distance to it forwardly. The control arm  58  extends underneath the roll  52  to a side opposite to the shaft  62  and ends at about the center of the roll  52 . The control arm  58  has an idler bar  68  or an angle extending parallel to the axis of roll  52  between the walls  48 . The brake arm  60  extends from the shaft  62  to a location above a completely wrapped roll  50  of the web  32  and has a cross element  70  designed to push onto the circumferential surface of the roll  50 , thereby pressing the roll  50  against the rear wall  46  and creating the wanted rolling resistance. As is apparent from the drawing, a downward, counter-clockwise movement of the control arm  58  will provoke a counter-clockwise movement of the brake arm  60  upon the roll  50  of the web  32 . 
         [0027]    The feeder  40  in this embodiment (see also  FIG. 3 ) is formed as a so-called duckbill, which however is not mandatory; it could be any other moving part pulling the web  32  from the roll  50  and feeding it into the bale chamber  16  through the gap  30 . The feeder  40  is composed of struts  72  on each side holding between them a carrier  74  in the form of a mouthpiece at a lower end thereof, two vertically distant bearings  76  in an upper region and a driver  78  positioned between the carrier  74  and the lower bearing  76  at the side of the strut  72  opposite of the carrier  74 . The carrier  74  as such is known and has two opposite plates biased onto each other to clamp a piece of the web  32  and move it forward. An upper link  82  and a lower link  84  forming part of a parallelogram linkage are connected with one end area to the bearings  76  and with their other end areas to the bearings  86  on the walls  48  being offset horizontally as well as vertically; lines through the bearings  76  at one end and bearings  86  at the other end do not run parallel, but divergently. The upper link  82  has an eye  88  on its upper side or a bore or the like useful to provide a connection to another part, as well as a journal  90 , which in this case, but not necessarily, is located between the eye  88  and the bearing  86 . An idler element  116  is connected to and connects the struts  72  on both sides and is provided between the carrier  74  and the driver  78 . As can be seen in  FIG. 3  this idler element  116  assists in feeding the web  32  in a proper way into the carrier  74 . The idler element  116  may consist of a simple bar or shaft. 
         [0028]    The separator  42  has two substantially S-shaped, but almost horizontally oriented arms  92  and a counter element  94 , which both serve to cut or separate a portion of the web  32  wound around a bale from a portion remaining on the roll  50 . In their rear end areas, shown at the left in the drawing and facing the bale chamber  16 , the arms  92  carry an upwardly oriented separating edge  96  or knife and a rubber block  122 , which is oriented the same way, but provided with respect to the separating edge  96  opposite of the bale chamber  16  and which forms one part of a retainer  98 . A bearing  100  is located substantially in the transition area between the two curves of the “S” and is followed by a bearing  102  at about ⅔ of the remaining length of the second curve and a bearing  104  at the end of the arms  92 . The counter element  94  is formed of bent sheet metal, which in this case is flexible to some extent and has a notch  106 , into which the separating edge  96  may enter and a plate  108  or surface, which is positioned such, that it can be contacted by the rubber block  122 , when the separator  42  is moved against it. The counter element  94  is attached to the walls  48  and located close to the gap  30 . The plate  108  forms another part of the retainer  98 . 
         [0029]    The actuating mechanism  44  includes a motor  110 , a link  112  and a spring  114 . The motor  110 , which may be actuated electrically, hydraulically or pneumatically is connected with one side to the walls  48  or any other stationary feature of the chassis  12  and with the other side to the eye  88  on the upper link  82 . The link  112  is a straight rigid bar extending between and connecting the bearings  90  on the upper link  82  and the bearing  100  on the arms  92 . The spring  114  is formed as a gas spring, but could be of any other kind, and is connected at one end to the walls  48  and at the opposite end to the bearing  104  at the end of the arms  92 . 
         [0030]    Connected to the clutch  54  and thus to the roll  52  are three indicators rotating with the roll  52 , once the web  32  is pulled from the roll  50 . A sensor  126  is located close to the travel path of these indicators to sense their movement. These indicators are offset angularly with respect to the actuators  56 . 
         [0031]      FIG. 7  shows the feeder  40  and the separator  42  in a side view, whereas at the underside of the carrier  74  a stripper  124  is attached. The stripper  124  is made of plastic and bolted, glued, riveted, snapped or otherwise fastened to the carrier  74 . The stripper  124  extends from the lower edge of the carrier  74  forward at a length, which is sufficient to reach the separating edge  96  when the feeder  40  and the separator  42  are moved relative to one another, as is shown in  FIGS. 7 and 8 . The length of the stripper  124  is chosen such, that it not only touches the tip of the separating edge  96 , but strips along a slanted surface terminating in the tip. As is apparent from the drawing, the stripper  124  will also strip along the opposite side of the separating edge  96 , when the feeder  40  moves from its position in  FIG. 2  to that of  FIG. 3 . The Stripper  124  extends over the full length of the separating edge  96 . 
         [0032]    Based on this structural description the function is described as follows starting from a state shown in  FIG. 2 , in which the web wrap apparatus  18  waits to be operated. In a state as shown in  FIG. 2 , the roll  50  with the web  32  is placed on the roll  52  and is secured in its position between the cross element  70  and the rear wall  46 . The arms  92  rest against the counter element  94  and the feeder  40  is in a position remote from the gap  30 . The web  32  extends from the roll  50 , underneath the roll  52  over the idler bar  68 , through the carrier  74  to a location between the separating edge  96  and the notch  106 , whereas it is clamped between the plate  108  and the rubber block  122  at a place slightly upstream of it. The driver  78  rests against the actuator  56  to keep the roll  52  from rotating. 
         [0033]    As soon as a manual or electrical signal is given to the actuating mechanism  44  to initiate wrapping the web  32  around a bale, the motor  110  is extended, thereby moving the arms  92  away from the counter element  94 , moving the feeder  40  downward and towards the gap  30 , which releases the driver  78  from the actuator  56 .  FIG. 3  shows, that the separator  42  moves away sufficiently to allow the feeder  40  to enter the gap  30 . Once the carrier  74  protrudes the gap  30 , the web portion hanging down from the carrier  74  is caught by the rotating bale and pulled from the roll  50 . Tension is created in the web  32 , since the roll  50  experiences friction on the wall  46  and since the roll  52  is hindered from free movement. According to  FIG. 4  the web  32  is inserted into the gap  30  and caught by the rotating bale.  FIG. 5  shows a situation, in which the motor  110  is retracted and thereby the feeder  40  is on its way back to a resting position and the driver  78  approaches the actuator  56 . Dimensions, locations and arrangements of the feeder  40  and the separator  42  are chosen such, that in the situation of  FIG. 5 , shortly before the web  32  is separated, the web  32  is pulled over the rubber block  122  at one side and over the counter element  94  on its other side, but not or hardly over the tip of the separating edge  96 . This helps to avoid unnecessary wear on the separating edge  96 , premature tearing of the web  32  and thus achieves a clean cut or separation of the web  32 . As a next step the driver  78  engages the actuator  56 , which rotates together with the roll  52 . As a result the link  112  is abruptly kicked upwardly, which assists the upward movement of the arms  92  initiated by the motor  110 , and the spring  114 . In order to dampen the shock on the roll  52  either the clutch  54  allows a slipping movement or if the clutch  54  contains rubber blocks or the like, the driver  78  will be accelerated by the first compressed and then expanding rubber. As a further consequence and as is shown in  FIG. 6  the accelerated separating edge  96  presses the web  32  into the notch  106  and clamps it as well between the rubber block  122  and the plate  108 , which increases tension in the web portion connected to the bale and finally leads to its separation. The piece of the web  32  extending from the separating edge  96  to the carrier  74  is the one hanging down, when wrapping starts again. 
         [0034]    Having described the preferred embodiment, it will become apparent that various modifications can be made without departing from the scope of the invention as defined in the accompanying claims.