Method and an apparatus for metering a liquid flow

A method of metering milk flowing from the teat cups of a milking machine, said method comprising:

• (a) passing said milk into a metering or measuring chamber containing floating means movably arranged therein, and including liquid inlet and liquid outlet passages, said outlet passage opening into said measuring chamber at the lower part thereof,
• (b) discharging said milk from said measuring chamber through said outlet passages in portions, the discharge of each portion being initiated in response to movement of said floating means to a predetermined upper level and caused by closing said liquid inlet passage and exposing said measuring chamber to atmospheric pressure while the discharge end of said outlet passage is communicated with the vacuum conduit of said milking machine, and
• (c) counting the number of portions discharged, the supply of atmospheric pressure to said measuring chamber being initiated when said floating means has been moved upwardly to a predetermined first level, whereafter milk is initially discharged from said chamber through a small bypass opening communicating with said liquid inlet passage, communication being established between said measuring chamber and a discharge end of said outlet passage when said floating means has reached a predetermined second lower level, whereby the liquid portion remaining in the measuring chamber is discharged through said outlet passage.

An apparatus for metering a liquid flow, said apparatus comprising:

• (a) a metering or measuring chamber having liquid inlet and outlet passages, said outlet passage opening into the lower part of said measuring chamber,
• (b) floating means movably arranged within said chamber,
• (c) discharge means for discharging said liquid from said measuring chamber through said outlet passage in portions, said discharge means being adapted to initiate discharge of each portion in response to movement of said floating means to a predetermined upper level by closing said liquid inlet passage and exposing said measuring chamber to a gas pressure exceeding the pressure at the discharge end of said outlet passage, said discharge means comprising a valve body for controlling said inlet passage and movable to an inlet passage closing position by the gas pressure supplied to said measuring chamber, said discharge means further comprising gas valve means controlled by said floating means so as to supply said gas pressure to the measuring chamber when said floating means has reached a predetermined upper position, said inlet valve body being shaped so as to define the upper part of said measuring chamber, a lower annular portion of said valve body being adapted to cooperate with a downwardly facing annular valve seat, and
• (d) means for counting the number of portions discharged.

An apparatus for metering a liquid flow, said apparatus comprising:

• (a) a measuring chamber having a liquid inlet passage, a liquid outlet passage, and an upper venting passage, said outlet and venting passages being exposed to vacuum,
• (b) a tubular valve body defining the upper part of said measuring chamber therein, said valve body having a lower annular valve body portion cooperating with a downwardly facing annular inlet valve seat, and an upper annular valve body portion having a smaller diameter than said lower valve body portion and cooperating with a downwardly facing venting valve seat,
• (c) floating means movably arranged within said measuring chamber,
• (d) valve means for connecting said measuring chamber to the atmosphere in response to upward movement of said floating means to a predetermined upper level, whereby said tubular valve body is moved to an upper portion in which said valve body portions engage with their corresponding valve seats, and for disconnecting the measuring chamber from the atmosphere in response to downward movement of said floating means to a predetermined lower level, whereby said tubular valve body is moved to a lower position in which said valve body portions are out of engagement with their corresponding valve seats so that the measuring chamber is in communication with said inlet and venting passages.

A method of metering a liquid flow, said method comprising:

• (a) feeding said liquid flow into a metering or measuring chamber in which a first pressure is maintained;
• (b) sensing the liquid level in said chamber;
• (c) interrupting said feed of liquid into the metering or measuring chamber and exposing the liquid therein to an increased second pressure in response to the sensing of a predetermined first liquid level in said chamber,
• (d) maintaining said increased pressure in said chamber during a time interval so as to reduce the volume of gas contained in the liquid in that chamber,
• (e) discharging liquid from said chamber, and
• (f) determining the amount of liquid being discharged from said chamber, on the basis of the liquid level sensed after lapse of said time interval but prior to initiating said discharge.

An apparatus for metering a liquid being fed into a metering or measuring chamber, said apparatus comprising:

• (a) level sensing means for sensing the liquid level within said measuring chamber;
• (b) means for interrupting the feed of liquid into said chamber and for increasing the pressure within said chamber during a period of time, said feed interrupting and pressure increasing means being controlled by said level sensing means,
• (c) means for discharging liquid from said chamber when said time period has lapsed, and
• (d) means for determining the amount of liquid being discharged from said chamber, on the basis of the liquid level sensed after lapse of said time period but prior to initiating said discharge.