Classifications

• • A—HUMAN NECESSITIES
  • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
  • A01J—MANUFACTURE OF DAIRY PRODUCTS
  • A01J5/00—Milking machines or devices
  • A01J5/017—Automatic attaching or detaching of clusters
  • A01J5/0175—Attaching of clusters
• • A—HUMAN NECESSITIES
  • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
  • A01J—MANUFACTURE OF DAIRY PRODUCTS
  • A01J5/00—Milking machines or devices
  • A01J5/007—Monitoring milking processes; Control or regulation of milking machines

Definitions

• the present invention relates to a sensing means and method for sensing for a milking machine of the type mentioned in the preambles of claims 1, 5 and 6.
• An object of the present invention is to provide sensor means and sensing methods which do not suffer from the disadvantages of the prior art system.
• the present invention relates to a teat cup attachment monitoring device for use in a milking machine in which teat cups are attached in sequence to teats and in which the attachment sequence is determined by control means.
• the teats cups are supplied with a working fluid from a common source which comprises means for measuring the pressure of the working fluid and comparison means for comparing the pressure of the working fluid and/or the rate of change of the pressure of the working fluid against a desired value of the pressure of the working fluid and/or the rate of change of the pressure of the working fluid.
• a teat cup attachment monitoring device is presented.
• the control means determines a time window for the attachment of each resp.
• teat cup and said comparison means compares the measured pressure of the working fluid and/or the rate of change of the pressure of the working fluid against a desired value of the pressure of the working fluid and/or the rate of change of the pressure of the working fluid during said time windows. In this way it can be detected if a teat cup has not been correctly attached and the resp. teat cup can be identified.
• a teat cup attachment monitoring device in which the working fluid is an underpressure connected to a teat space in each teat cup. It is therefore possible to use this device with already existing teat cups which use an underpressure in the teat space.
• a teat cup attachment monitoring device in which the working fluid is compressed air or liquid connected to a pulsation chamber in each teat cup. It is therefore possible to use this device with already existing teat cups which use compressed air or liquid in the pulsation chamber.
• a teat cup attachment monitoring device in which means for measuring the pressure of the working fluid comprising a single pressure sensor provided on a common working fluid line connected between said teat cups and a working fluid source.
• the device can be constructed economically as one pressure sensor can be used to monitor several teat cups.
• a method for monitoring the attachment of teat cups in a milking machine comprises the steps of: providing a single pressure sensor in a common working fluid line connected between teat cups and a working fluid source; providing a series of sequential time windows (tw ⁇ -tw_ ⁇ ) during which a respective teat cup is to be attached to a teat; monitoring the pressure in the common working fluid line during each time window; comparing the monitored pressure for each time window against a desired pressure for each time window; determining that said resp. teat cup is incorrectly attached if the monitored pressure during the resp. time window is different to the desired pressure for the resp. time window.
• Using this method leads to that the device can be constructed economically as one pressure sensor can be used to monitor several teat cups.
• a method for monitoring the attachment of teat cups in a milking machine which has the steps of: providing a single pressure sensor in a common working fluid line connected between teat cups and a working fluid source; providing a series of sequential time windows during which a respective teat cup is to be attached to a teat; attaching said resp. teat cup to a teat during said resp. time window; monitoring the rate of change of pressure in the common working fluid line during each time window; comparing the monitored rate of change of pressure for each time window against a desired rate of change of pressure for each time window; determining that said resp. teat cup is incorrectly attached if the monitored rate of change of pressure during the resp. time window is different to the desired rate of change of pressure for the resp. time window.
• Using this method leads to that the device can be constructed economically as one pressure sensor can be used to monitor several teat cups.
• a method for monitoring the attachment of teat cups in a milking machine which has the steps of: that if teat cup is determined to be incorrectly attached it is removed and the attaching, monitoring, comparing and determining steps are repeated.
• This method provides a way of automatically refitting an incorrectly attached teat cup without requiring any operator intervention.
• a single vacuum sensor is provided in a suction line common to all the teat cups.
• the milking machine has a control device, such as a computer, which controls a teat cup attaching means such as a robot arm. This arm is commanded by the computer to offers one teat cup at time to its intended teat on the animal. As each teat cup is correctly attached the air flow through each respective teat cup is stopped and the pressure in the suction line is reduced. The pressure in the suction line is sensed by the vacuum sensor and the sensed value monitored by the control device during the attachment operation.
• the control device concludes that the teat cup is incorrectly attached and orders the robot arm to attempt to reattach the teat cup.
• the rate of change of the sensed pressure in a pressure line connected to a pulsation chamber in a teat cup is measured.
• a pulsating pressure is applied to the pulsation chambers of all the teat cups as they are being attached. If a teat cup contains a teat then the rate of the rise in pressure in the pulsation chamber will be greater than if there is no teat in the teat cup. This is because in the first instance the inward expansion of the pulsation chamber wall will be resisted by the teat after only a short period of time. The resistance exerted by the teat causes the pressure to rise.
• Fig. 1 shows schematically a first embodiment of a milking machine in accordance with the present invention
• Fig. 2a) - 2c) show examples of a graphs showing pressure against time sensed by a sensor while teat cups are attached in a correct way or while incorrect attachment of teat cups occur, all of the figures according to the first embodiment of the present invention
• Fig. 3 shows schematically a second embodiment of a milking machine in accordance with the present invention
• Fig. 4 shows an example of a graph showing the pressure against time sensed by a sensor according to the first embodiment of the present invention.
• FIG. 1 shows a schematic arrangement of a milking machine 1 for automatic milking of a dairy animal such as a cow, goat, buffalo or the like.
• the teat cups are attached to the teats 13 '-13 "" one after the other by the robot arm 3.
• the attachment sequence is determined and controlled by control means, preferably computer 5 which provides a time window tw ⁇ -tw4 for attaching each teat cup 9'- 9"".
• Each teat cup 9'-9"" has a respective teat space 15'-15"” and pulsation chamber 35 '-35'"' each connected to a working fluid supply.
• the working fluid is underpressure air for the teat cups and compressed air for the pulsation chambers.
• the air supply lines being omitted.
• Each teat cup 9'-9"" is connected by a respective teat cup underpressure line, commonly called a vacuum line, 17'-17"" to common vacuum line 19 which is connected to suction supply means such as a so-called vacuum tank 21 and vacuum pump 23.
• a pressure sensor 25 is connected to, and senses the pressure in, common vacuum line 19. The sensed pressure is transmitted to computer 5.
• computer 5 can decide that the respective teat cup 9 '-9'"' being attached during the time window twi -tw4 was correctly attached. If no, or an insignificant, change in pressure is detected then computer 5 can decide that the respective teat cup 9 '-9'"' is not correctly attached and it can command the robot arm 3 to attempt to attach the resp. teat cup 9'-9"" again.
• Figure 2a shows a graph of pressure sensed in the common vacuum line against time while a correct attachment of four teat cups 9 '-9'"' is performed.
• Figure 2b) shows a similar graph in which the third teat cup 9 ' " is incorrectly attached on the first attempt in time window 1W3 but this teat cup is subsequently correctly attached in time window tw3 ' .
• the rate of change of pressure in common vacuum line 19 is monitored.
• a teat cup 9 '-9'"' is attached to a teat the reduction in pressure occurs gradually as more of each teat 13 '-13'" is introduced into the respective teat cup 9'-9"".
• any of the teat cups 9 '-9'"' is incorrectly placed with its open end against the udder of the animal or a surrounding surface then it may become attached to the udder or surface because of the suction caused by the vacuum in the teat cup. This attachment will occur suddenly and cause an unusually rapid drop in the pressure in common vacuum line 19. If this is detected the computer 5 can command robot arm 3 to reattempt to attach the respective teat cup 9'-9"".
• a milking device has control means 26 for controlling robot arm 27.
• a working fluid such as compressed air is supplied from a pump 28 to a compressed air reservoir 29.
• a common pressure line 30 connects the reservoir 29 via a valve 31 to individual compressed air supply lines 32 '-32'"' each leading to a resp. pulsation chamber 35 '-35'"' in a resp. teat cup 9' -9"".
• the rate of change of the sensed pressure in the common pressure line 30 is measured by a pressure sensor 34.
• a pressure sensor 34 For the sake of ease of illustration only schematic attachments points for the vacuum supply lines for the teat chambers are shown in this figure, the vacuum supply lines being omitted.
• valve 31 is operated so that a pulsating pressure is applied to the pulsation chambers 35 '-35'"' of all the teat cups 9 '-9'"' as they are being attached.
• This pulsating pressure causes the flexible pulsation chamber walls 36 '-36 " " to expand and contract. If a teat cup 9 '-9'"' contains a teat then the rate of the rise in pressure measured by pressure sensor 34 will be greater than if there is no teat in the teat cup 9'-9"".
• the rate of fall in pressure depends on the presence or absence of teats in the pulsation chambers.
• the working fluid could be air at an underpressure from a vacuum source, the desired pulsating pressure being produced by allowing air at atmospheric pressure to enter the pulsation chambers while a vacuum is connected to the teat space.

Landscapes

• Life Sciences & Earth Sciences (AREA)
• Animal Husbandry (AREA)
• Environmental Sciences (AREA)
• Measuring Fluid Pressure (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=20411663

Family Applications (1)

Country Status (4)

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Family Cites Families (6)

• 1998
  • 1998-06-11 SE SE9802078A patent/SE515127C2/sv unknown
• 1999
  • 1999-06-11 AU AU48126/99A patent/AU4812699A/en not_active Abandoned
  • 1999-06-11 EP EP99931689A patent/EP1083785A1/de not_active Withdrawn
  • 1999-06-11 WO PCT/SE1999/001039 patent/WO1999063806A1/en not_active Application Discontinuation

Non-Patent Citations (1)

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