Abstract:
An apparatus for automatically milking an animal, comprising at least one teatcup having a teat entrance end ( 17   a ), and a movable arm ( 6, 40 ) for moving the teatcup toward a teat of an animal to be milked and attaching it thereto. The teat entrance end of the teatcup is arranged, while being moved by the movable arm ( 6, 40 ) toward the teat, to be held in relation to the movable arm ( 6, 40 ) at a level which is different from that of the teat entrance end ( 17   a ) of a further teatcup, when held in relation to the movable arm.

Description:
TECHNICAL FIELD OF THE INVENTION 
     The present invention relates to an apparatus for automatically milking an animal comprising at least one teatcup having a teat entrance end, and a movable arm for moving said teatcup towards a teat of an animal to be milked and attaching it thereto. 
     BACKGROUND OF THE INVENTION 
     An apparatus of this kind is known from WO 90/07268, which suggests that teatcups are brought to the teats of a cow by means of a robot arm. The teatcups are moved one at a time by means of the robot arm under the belly between the front and rear legs of the cow, and rearwards towards the udder. 
     An object of the invention is to improve the success rate of teatcup attachment. 
     This has been obtained by an apparatus of the initially defined kind, which is characterised in that the teat entrance end of said teatcup is arranged, while being moved by said movable arm towards said teat, to be held in relation to said movable arm at a level which is different from that of the teat entrance end of a further teatcup, when held in relation to said movable arm. 
     Hereby, it is not necessary to detach a teatcup on a front teat while re-attaching a teatcup, which has fallen off a rear teat in cases where the movable arm is moved towards the udder in a direction towards the rear of the cow. 
     Preferably, said movable arm is provided with an end portion, for holding a plurality of teatcups, wherein said at least one teatcup is held at a level, which is different from that of said further teatcup held by said end portion. 
     Suitably, said end portion is provided with a first part holding said at least one teatcup at a first level, and a second part holding said further teatcup at a second level. Hereby is achieved that the teatcups are allowed to be held at different levels. 
     Preferably, said first part of the end portion is arranged substantially parallel to said second part, said first and second parts being interconnected by an intermediate portion. Hereby, the teatcups are allowed to move between the different levels. 
     Suitably, said end portion is provided with a teatcup supplying means for moving a teatcup from said first part to said second part. Hereby, the teatcups are allowed to be actively moved between the different levels. 
     Preferably, said teatcup supplying means comprises a guide means and a supplying member, said supplying member being arranged to move at least one teatcup along said guide means towards said second part. In particular, said guide means comprises a pair of parallel guide members. 
     Suitably, said at least one teatcup and said further teatcup are arranged to co-operate with a connection means of said end portion in such a way, that they are held at different levels in relation to said end portion. 
     Preferably, said at least one teatcup and said farther teatcup are movable away from said end portion, independently from one another. 
     Suitably, said at least one teatcup has a longitudinal extension, and said further teatcup has a longitudinal extension, the longitudinal extension of said at least one teatcup being different from the longitudinal extension of said further teatcup. Hereby, different lengths of the teatcups are achieved. 
     Preferably, said at least one teatcup and said movable arm are provided with an identification means for allowing establishment of the identity of said at least one teatcup. Hereby, it is possible to determine which teatcup is to be or has been attached to a teat. 
     In particular, said at least one teatcup is provided with a bar code, and said movable arm is provided with a laser reader for reading said bar code. Hereby, a quick identification of the teatcup is achieved. 
     Suitably, said at least one teatcup is connectible to a vacuum source, a teat cleaning means being adapted to be connected at the teat entrance end of said at least one teatcup by means of a vacuum prevailing in the teatcup. Hereby, a teat cleaner is allowed to be fetched by the movable arm without the use of a gripper. 
     Suitably, the teat entrance end of said at least one teatcup is arranged at a higher level that the teat entrance end of the further teatcup, as seen in a vertical plane. Hereby, it is possible to apply a teatcup onto a rear teat, when a front teat has a teatcup attached thereonto. 
     Preferably, said movable arm is a service arm, which supplies one or more teatcups to a desired position, for allowing a robot arm with a gripper to grip a teatcup. 
     Alternatively, said movable arm is a robot arm. 
     Suitably, said robot arm is provided with laser sensor. Hereby, the position of a teat is possible to be located. 
     In particular, said laser sensor comprises a laser transmitter for forming a line, such as a scanning laser beam or a stable or scanning laser plane, and a laser reader, such as an image capturing device. 
     Suitably, said laser reader is adapted to read bar codes. Accordingly, the location of a teat and the identity of a teatcup with applied bar-codes is possible to be established by means of the same laser sensor. 
    
    
     DRAWING SUMMARY 
     FIG. 1 is a perspective view of an animal stall provided with a milking robot. 
     FIG. 2 illustrates a first embodiment of the invention. 
     FIGS. 3A to  3 C illustrate a second embodiment of the invention. 
     FIGS. 4A to  4 C illustrate a third embodiment of the invention. 
    
    
     DETAILED DESCRIPTION 
     FIG. 1 shows robot milking stall  2  provided with a milking robot  4  having a movable arm in form of a robot arm  6  with a gripping means  7  adapted to grip one teatcup. A teatcup rack  8  is provided with four teatcups  10 ,  12 ,  14 ,  16 , each teatcup having a teat entrance end  17   a  and a milk exit end  17   b . According to a first embodiment of the invention, two teatcups  10 ,  12  thereof are of the same or similar length, while two other teatcups  14 ,  16 —of the same or similar length—are shorter than the other two teatcups  10 ,  12 . 
     An udder  18  of a cow has rear teats  20 ,  22 , and front teats  24 ,  26 . The robot arm shown in FIG. 1 is intended to bring the teatcups  10 ,  12 ,  14 ,  16  under the belly and between the front and rear legs of a cow. In this case, the teatcups  10 ,  12  are to be attached to the rear teats  20 ,  22 , whereas the teatcups  14 ,  16  are to be attached to the front teats  24 ,  26 , for reasons that will be apparent below. 
     An image capturing device  28 , such as a digital video camera is arranged on the side of the stall  2 , for viewing at least the udder  18  of the cow, before, during and/or after teatcup attachment. 
     The robot arm  6  is provided with an angular end portion  30 , which is provided with a teat location means  32 , in the form of a digital video camera and/or a laser sensor, and the gripping means  7 . This allows for a movement of a teatcup towards the rear of the cow, while viewing in the same direction. The angular end portion may be e.g. perpendicular 
     After optional cleaning of the teats, one of the longer teatcups  10  is attached to a rear teat  20 . Then, the other one of the longer teatcups  12  is attached to the other rear teat  22 . Subsequently, one of the two shorter teatcups  14  is attached to a front teat  24 . Thereafter the other one of the shorter teatcups  16  is attached to the other front teat  26 . 
     Alternatively, one of the longer teatcups  10  is attached to a rear teat  20 . Then, one of the two shorter teatcups  14  is attached to a front teat  24 . Then, the other one of the longer teatcups  12  is attached to the other rear teat  22  and thereafter the other one of the shorter teatcups  16  is attached to the other front teat  26 . 
     FIG. 2 shows a situation where one of the longer teatcups  10  for some reason has fallen off one of the rear teats e.g.  20  and therefore (or for any other reason) has to be re-attached thereonto, while a shorter teatcup e.g.  14  is still attached to a front teat  24  in front of that rear teat  20 . In this case, the longer teatcup is allowed to be re-attached to the rear teat  20  without having to first detach the teatcup  14 , as the teat robot arm end portion  30  will be able to pass the short teatcup  14 . 
     It should be noted that it would be possible to arrange the milking robot  4  behind the stall  2 , in which case the robot arm  6  should be adapted to move each teatcup between the rear legs of the cow. Such a robot arm  6  should preferably be straight, rather than having an angular end portion  30 . The longer teatcups  10 ,  12  are in that case to be attached to the front teats  24 ,  26  and the shorter teatcups  14 ,  16  to the rear teats  20 ,  22 . 
     A further image capturing device  28  may be arranged on the opposite side of the stall  2  for viewing at least the udder  18  from that side. 
     FIG. 3A illustrates a second embodiment of the invention, in which the teatcup rack  8  in FIG. 1 is substituted by a teatcup supply means  40  hingedly arranged on the robot arm  6 . The teatcup supply means  40  constituting said movable arm is allowed to rotate about the hinge by means of a pneumatic or hydraulic cylinder  41 . The teatcup supply means  40  is provided with a pair of parallel elongated members  42 ,  44 , defining an intermediate elongated space  46 . The members  42 ,  44  and the space  46  have a fork like configuration, i.e. the elongated space  46  has an open end  47 . It should be noted that the cylinder  41  may be substituted by an electric step motor. 
     The members  42 ,  44  are furthermore formed to comprise a lower portion  48 , an upper portion  49  and an intermediate portion  50 . The upper portion  49  is adapted to house one teatcup  52 , whereas the lower portion  48  is adapted to house a row of three teatcups  54 ,  56 ,  58 , the four teatcups  52 ,  54 ,  56 ,  58  preferably—but not necessarily—being of the same length. The teatcups  52 ,  54 ,  56 ,  58  are provided with an annular flange member  59 , which rests on the elongated members  42 ,  44 , such that the teatcups are kept in the elongated space  46 . 
     A conveying means  59   a  driven by a driving means  59   b , in the form of a spring, an electric motor or a hydraulic or pneumatic cylinder, is adapted to push the teatcups towards the upper part  49 . When the teatcup  52  is removed from the upper portion  49  the teatcups  54 ,  56 ,  58  will be pushed in a sliding movement towards the upper portion  49  via the intermediate portion  50 . 
     The different levels of the teat supply means  40  allows for a re-attachment of a teatcup which has fallen off a teat without having to first detach a teatcup attached to a teat in front of the other teat, as the portion  49  will be able to pass the already attached teatcup. 
     If an attached teatcup still disturbs the movement of the teatcup supply means  40 , it is simply turned about the hinge by means of the cylinder  41 , until the attached teatcup can be passed. 
     FIG. 3B illustrates a stall  2  provided with a milking robot  4  with the robot arm  6  and the teatcup supply means  40  shown in FIG.  3 A. When the teatcup  52  has been attached to a teat, the robot arm  6  retracts the teatcup supply means  40  horizontally, away from the attached teatcup, which slides off the upper portion  49  via the open end  47 . The conveying means  59   a  then pushes the three teatcups  54 ,  56 ,  58  on the lower portion  48  towards the upper portion  49 , which results in that the teatcup  54  slides to the upper portion  49  via the intermediate portion  50 . The conveying means is retracted again, if needed, such that the two remaining teatcups  56 ,  58 , are kept on the lower portion  48 . 
     The sequence is repeated until all the teatcups have been attached to the respective teats. 
     FIG. 3C illustrates the teatcup supply means  40  shown in FIG. 3A arranged as a service arm, which is hingedly arranged about a vertical axis A, and movable in a horizontal plane about the hinge to suitable positions (cf. the broken lines) by means of a not shown electric step motor or hydraulic or pneumatic cylinder, in the same manner as shown in FIG.  3 A. The movement of service arm is controlled by a computer, which is associated with the teat location means  32  on the robot arm. Of course, a separate camera, as the one shown in FIG. 1, (reference numeral  28 ) may be used to view the movement of the service arm. The computer will then, of course, act in response to that camera, or in combination with the teat location means  32 . 
     During teatcup attachment, the service arm supplies a teatcup at the udder  18 . The teatcup is gripped by the gripper  7  of the robot arm  6 , which has a straight end portion  30 . The teatcups are simply slid off the end portion  47  by the robot arm  6  and attached to a suitable teat (cf. the embodiment according to FIGS.  3 A and  3 B). The next teatcup is slid to the upper portion  49  and the gripper  7  grips it—and also the subsequent teatcups—at substantially the same place in space as it gripped the previous teatcup. The need for moving the robot arm when fetching the teatcups is accordingly immensely reduced, which results in a quicker and safer teatcup attachment. 
     FIGS. 4A-4C show a third embodiment of the present invention, in which four teatcups  60 ,  62 ,  64 ,  66  are disengagably disposed in a vertically displaced relationship on the end portion  30 . Each of the teatcups is provided with a bar code  70 , for allowing identification thereof by means of a teat location means  32  in the form of a laser sensor (cf. FIG.  3 C). The laser sensor is of the kind described in detail in WO 97/15900, and is furthermore able to read bar codes. 
     The teatcup  60  is to be attached to the rear teat  20  of the udder  18 . For this purpose, the laser sensor  32  locates the position of the teat  20  and furthermore establishes the identity of the teatcup  60 . It is desirable that none of the other teatcups is allowed to be attached to that teat, as it would cause troublesome further teacup attachment. 
     When the teatcup  60  has been attached to the teat  20 , the teatcup is released from the end portion  30 . The teatcup  62  is then ready to be attached to the teat  22 . 
     After performed milking the teatcups are individually detached from the relevant teat and returned to the end portion  30  of the robot arm  6  by means of e.g. a cord (not shown). 
     The attachment of the teatcups  60 ,  62 ,  64 ,  66  to the end portion  30  may be performed by means of e.g. electromagnets (not shown) or vacuum nozzles (not shown).