WO1983002874A1

WO1983002874A1 - A method of weighing-in milk in milk tankers and a milk tanker for carrying out the method

Info

Publication number: WO1983002874A1
Application number: PCT/DK1983/000021
Authority: WO
Inventors: A/S Pasilac
Original assignee: ANDREASEN, Christian, Moller; Kiaer, Lars
Priority date: 1982-02-23
Filing date: 1983-02-23
Publication date: 1983-09-01
Also published as: SE8305689D0; NL8320058A; FI833822A; DE3332434T1; NO833843L; DK473583D0; GB2125671A; DK77482A; FI833822A0; DK473583A; SE8305689L; GB8327721D0; EP0101489A1

Abstract

A method of weighing-in milk in milk tankers for collecting milk from suppliers, in which the milk is pumped into a weighing tank (5) and during travel from one supplier to another is pumped fro m the weighing tank (5) into collection tanks (3, 4). The weighing is effected by means of a weighing means (8), and the weighing tank is during weighing released from supporting means (7). The weighing tank (5) is connected to a pump which is used for filling the weighing tank (5) as well as for draining said tank into collection tanks (3, 4). By draining the weighing tank into collection tanks during travel, time is saved at each supplier's, and the weighing eliminates inaccurate measuring due to intake of air during pumping as well as to milk intermixed with air.

Description

A method of weighing-in milk in milk tankers and a milk tanker for carrying out the method.

When milk is collected from the suppliers of a dairy in specifically equipped tankers, the amount of milk delivered from each supplier is normally measured by means of a volumetric liquid meter, the milk by means of a pump on the tanker being sucked from milk cans or cooling tanks at the supplier's. During the suction it is practically impossible to prevent air from being sucked up together with the milk and it is therefore necessary to include an air separator in the pipe system of the tanker before the liquid meter, as air passing the meter would be registered as milk. In practice, it has proved impossible to suffici¬ ently degas the milk to obtain accurate measuring.

Moreover, there is a big difference in the ability of milk to release air as cold milk is more difficult to degas than hot milk, and milk having a high content of fats is more difficult to degas than milk having a lower content of fats.

Further, the intermixture of air varies in the treatment of the milk in milking machines.

When settling the milk account by the weight it is therefore necessary to use a conversion table in order to have the measured amount of milk approximately convert¬ ed from liters to kilos.

The difficulties involved with the volumetric measuring of the milk may be entirely eliminated by weigh¬ ing the milk. Intermixture of air in the milk during suction would then be of no significance, but weighing entails the problem that the weighing vessel normally has to be drained while the tanker is stationary, thus in¬ volving an increase of the service time at each supplier's. Even a small delay in each service would add up substantial¬ ly.

It is the object of the invention to provide a method of weighing-in milk collected in tankers from the milk suppliers of a dairy so as to solve the said problem in a simple way. The characteristic of the method according to the invention is that a supplier's milk is pumped into a weigh- ing tank (5) positioned on the tanker and weighed, and that the milk is subsequently pumped into a collection tank (3 or 4) positioned on the tanker. Such pumping may take place during the travel of the tanker to the next supplier.

The increase of service time otherwise caused by weighing may thereby be avoided as travel to the next- supplier may be started immediately after registering of the milk delivered as is also the case by using volumetric measuring.

The invention further relates to a milk tanker for carrying out the method according to the invention, and the characteristic of the milk tanker of the invention is that in addition to one or more tanks for collection of milk it has a separate, preferably smaller weighing tank connected to one or more weighing cells. According to the invention the tanker may have means for releasing the weigh¬ ing tank during weighing from means serving to stabilize the tank during travel.

For this purpose the weighing tank according to the invention may be connected to a lif ing device by weighing means so that the weighing tank is lifted free of its supports simultaneously with loading of the weigh¬ ing means by the weight of the weighing tank. These scales may according to the invention be formed of three weighing cells arranged as a three-point suspension providing balanced lifting even if the tanker should slant to one side.

Like the conventional milk tankers, the tank truck according to the invention may have a pump housing with a pump for suction of the milk from the suppliers' stor¬ age vessels. According to the invention, the same pump is preferably used for suction and filling the weighing tank and for pumping the milk from the weighing tank to the collection tank or tanks. The pump may according to the invention be reversible,and forked pipes connected to one stud of the pump connected to the suction house for intake of milk and pipes leading to the collection tank or tanks, respectively, are provided with check.valves so that by reversing the direction of rotation of the pump only, milk may be sucked into the weighing tank or transferred from the weighing tank to the collection tank.

In order to provide against partly inaccurate weighing and partly inadvertent loading of the weighing cells and the weighing tank during travel, the means according to the invention, which during weighing release the weighing tank from means for stabilizing the tank during travel, and/or the means for stabilizing the weigh- ing tank during travel may be operationally connected to the parking brake system of the tanker.

Moreover, the pipe system of the tanker serving for transporting milk may be adapted for pneumatic draining of the pipes. This secures in a simple way that all milk be transferred to the weighing tank or from the weighing tank to the collection tanks before the next delivery of milk is received.

Finally, the tanker according to the invention may be provided with a spirit level adapted to provide a control signal by inadvertent inclination of the tanker. This secures accurate weighing.

The invention will be further explained below with reference to the drawing in which

Figure 1 schematically shows an embodiment of a milk tanker according to the invention, partly in section. Figure 2 schematically in perspective the tanks of the milk tanker with associated pump and pipe system. Figure 3 another embodiment of part of the pipe system shown in Figure 2,

Figure 4 in enlarged scale a cross section through part of a weighing tank.

Figure 5 a plan view of the weighing tank of

Figure 4,

Figure 6 a diagrammatic cross section through another embodiment of the invention.

Figure 7 a diagrammatic side view of part of a tanker comprising the embodiment according to Figure 6,

Figure 8 a top view of the embodiment of Figure 7,

Figure 9 a diagrammatic longitudinal section through the weighing tank of the embodiment according to Figures 6-8, and

Figure 10 a diagram of a fluid control system for operation of the embodiment according to Figures 6-9.

In the drawing. Figure 1 shows a truck chassis 1 on which a tank unit 2 is mounted. In the shown embodiment, the tank unit 2 comprises two collection tanks 3 and 4, a weighing tank 5 and a pump housing 6. The weighing tank is carried on supports 7 attached to the sides of the tank unit 2. The top of the weighing tank 5 is linked to a weighing cell 8 which in turn is linked to a lifting device 9 mounted on the top surface of the tank unit 2.

The weighing tank 5 has a bottom outlet 10 which through a flexible pipe, e.g. a hose 11, is connected to a not shown pipe system in the pump housing 6.

The pipe system with pump in the pump housing 6 is schematically shown in Figure 2 together with the collect¬ ion tanks 3 and 4 as well as the weighing tank 5, the truck chassis 1 and the casing of the tank unit 2 left out.

A flexible pipe 11 connects the bottom outlet 10 of the weighing tank 5 with a reversible pump 12 by means of a pipe 13. The pump 12 is also connected with a pipe 14 which through pipes 19 and 20 is connected with the collect¬ ion tanks 3 and 4. The pipe 14 has a fork 15 connected to a hose 16 having at its end a suctio n pipe 17. Between the fork 15 and the pipes 19 and 20 a check valve 18 is in¬ serted on the fork 15. The pipes 19 and 20 have stop cocks 22 associated with a discharge pipe 23 also provided with a stop cock 22. The pump 12 is driven by a not shown motor which may be hydraulic or electric. The pump may through a transmission be connected to the motor of the truck.

When milk is collected from a supplier, the suct¬ ion pipe 17 is submerged in the supplier's milk can, and the pump 12 is started with a direction of rotation so as to pump the milk in direction of arrow 24. The milk is thereby pumped through the hose 16 and the pipes 15, 14, 13 and 11 into the weighing tank 5, the check valve 21 preventing milk from the tanks 3 and 4 from being sucked into the weighing tank 5 too. The milk in the weighing tank 5 is weighed while being lifted by the lifting device 9 so as to be free of the supports 7 (Figure 1) , and pulses from the weighing cell 8 are registered on a not shown board in the pump housing. After weighing, the weighing tank 5 is relowered so as to rest again on the supports 7, and the pump 12 is started with reverse direction of rotat¬ ion, and the milk is pumped as indicated by arrow 25 through the pipes 11, 13, 14 and 19 or 20 from the weigh¬ ing tank 5 into one of the tanks 3 or 4. A check valve 18 prevents the milk from flowing into the hose 16.

The check valve 21 may be of the type which may be permanently locked by a.locking device, or a stop cock may be inserted between the fork 15 and the pipes 19 and 20 so as to block the connection to the pump 12 and the fork 15 when the tanks 3 and 4 are to be drained through the dis¬ charge pipe 23 in the dairy. Draining of the tanks 3 and 4 may be effected by means of a pump in the pump housing or by connection to a stationary pump in the dairy.

The weighing tank 5 may be used as a supplementary collection tank when the tanks 3 and 4 are full, as the milk delivered from the last supplier may be determined by simple arithmetic even if there is milk in the weighing tank when further milk is pumped up, thereby utilizing the otherwise considerable waste of space caused by the weighing tank 5 according to .the invention if empty.

When part of the pipe system shown in Figure 2 is changed as shown in Figure 3, the reversible pump 12 may be replaced by a pump 40 where the flow through the pump remains as shown by arrow 25. The suction side of the pump 40 is connected to a two-way valve or three-way cock 26 so as to enable connection of the pump either with the hose 16 or the pipe 13.

The pressure side of the pump 40 is connected to a two-way valve or three-way cock 27 so that the pump 40 may either be connected to the pipe 13 and thus to the weighing tank 5 through a pipe 28, or to the pipe 14 and further to the collection tanks 3 and 4 as shown in Figure 2, the check valve 21, however, being left out.

During filling of the weighing tank 5 milk is sucked into the pump 40 through the suction pipe 17 and the hose 16, the two-way valve 26 being set so as to provide connection from a to b and blocked to c. On the pressure side of the pump 40 connection is provided through the two-way valve 27 from a to b and blocked to c so that the milk is pumped through the pipes 28, 13 and 11 into the weighing tank 5. When the milk is pumped from the weighing tank 5 to the collection tanks 3 and 4, the two-way valve 26 is set for connection between b and c, and the two-way valve 27 provides connection between a and c. Now, the milk is pumped from the weighing tank 5 through the pipes 11, 13, 14, 19 and/or 20 to the collection tanks 3 and/or 4.

In the pipe system shown in Figure 3, the pump 40 may be used for draining the collection tanks 3 and 4 by providing a fork having a valve 29 between the pressure side of the pump 40 and the two-way valve 27 as well as a stop cock 30 on the pipe 13 between the pipe 28 and the pipe 11, the two-way valve 27 in that case being set for connection from c to b and the two-way valve 26 for con¬ nection from c to b while the valve 29 is opened.

Figures 4 and 5 show in detail the weighing tank 5 comprising supports and lifting device 9. Supporting strips 39 are attached to the wall of the weighing tank 5, said strips engaging contact surfaces 37 of the supports 7 when

the weighing cell 8 is relieved. The weighing tank 5 has above a manhole cover 32 clamped by not shown means to a shoulder 31 which is welded to the wall of the weighing tank 5. The cover 32 is hinged to the weighing cell 8, the top of which is hinged to the movable part of the lift¬ ing device 9. The lifting device 9 has a foot 36 attached to a cover 34 fastened to a curb 33 which in turn is attached to the upper surface of the tank unit 2. The foot 36 has holes through which the stud is removable from the hinge between the lifting device 9 and the weighing cell 8 so as to dismantle the cover 34 and provide access to the weighing tank 5.

When the weighing tank 5 including its contents is to be weighed, it is lifted by means of the lifting device 9, as indicated by dotted line, so as to be free of the supports 7. After weighing, the weighing tank 5 is return¬ ed to its place by guide surfaces 38 of the supports 7, as it is feasible that the tanker may be slanting during weighing. As shown in Figure 5, the guide surfaces 38 are^' fixed at the ends of the supporting strips 39 so that the weighing tank 5 is guided into place in two directions.

In the shown embodiment, the lifting device 9 is a hydraulic cylinder, and the weighing cell 8 is a hydraulic or electronic weighing cell with slight or no movement of the indicator means during weighing. The pulses from the weighing cell 8 are transferred through not shown lines or pipes to a not shown pointer instrument in the pump housing.

The invention is not limited to the embodiment shown. Instead of the system of Figure 4 in which the weighing tank 5 during weighing is suspended in a single weighing cell 8, the weighing tank may e.g. rest on a supporting frame which is carried by three weighing^' cells whose pulses are added so that the total weight is indic¬ ated on the pointer instrument in the pump housing.

In such an embodiment of the invention, the lifting devi-ce 9 may be redundant, as it can be replaced by movable means of another type for fixing the weighing tank during travel.

In the shown embodiment, the tank unit has two collection tanks 3 and 4 so that the tanker may be used for simultaneous transport of return products as for in¬ stance skim-milk and collection of raw milk because the pump housing 6 in addition to that shown in Figure 2 and/or Figure 3 includes a pump and metering equipment for discharge of the return product. Thus, the tanker accord- ing to the invention may have a single collection tank if used for collection only, or more than two tanks if carry¬ ing several return products.

Figures 6-9 show an embodiment of the weighing means formed of three weighing cells 40 which as shown in Figure 8 are arranged as a three-point suspension. By means of a linkage system 41 the cells 40 are connected to two pneumatic diaphragm cylinders 42 by means of which the weighing tank 5 may be lifted from fulcrum position to weighing position - and vice versa - so that in the weigh¬ ing position the tank is suspended in the weighing cells 40. The arrangement is such that weighing of the contents of the tank 5 is permissible even if the chassis of the truck might incline by 10 from horizontal.

For stabilizing it during travel the tank 5 is in the lowered position retained by locking means 43 arranged at the sides of the tank.

During preparation for weighing-in milk, the lock¬ ing means 7 are released, the pneumat ic diaphragm cylind¬ ers 42 are supplied with pressurized air and by means of the linkage system 41 and the weighing cells 40 the tank 5 is lifted.

The milk is then pumped through a hose 44 connect¬ ed to a pipe 45 opening at the bottom of the weighing tank 5. The tank is vented through a pipe 46.

Upon completed weighing the milk is sucked through the pipe 45 and the hose 44 from the weighing tank 5 and transferred to the collection tanks 3 and 4. Before the next travel of the tanker the diaphragm cylinders 42 are vented, the tank 5 thereby being lowered. During lower¬ ing the tank is guided into place by means of control feet 47 located at the bottom of the tank, said feet engaging subjacent recesses 48 in the bottom of the tanker. The locking means 43 engage rails 49 located on the sides of the tank 5, thereby retaining the tank 5 during travel.

In the shown embodiment, the locking means 43 are pneumatically controlled by means of pneumatic cylinders 50. These cylinders are together, with the membrane cylind¬ ers 42 connected to a compressed-air system which is coupled to the parking brake system of the tanker. The coupling diagram is shown in Figure 9.

The operation of the system is based on an air pressure prevailing in the brake system when the parking brake is released during travel, whereas the system is evacuated at standstill when the parking brake is actuated.

The system is by means of a pipe 51 connected to the pneumatic system of the parking brake which is not shown.

A compressed-air tank 52 is through a pipe 53 con¬ nected to a magnet controlled valve 54 which is opened when an identification card of the supplier is inserted in¬ to a not shown electronic control system. The compressed air is then supplied to the cylinders 50 of the locking means so as to release the locking means 43.

Though not shown in detail, the arrangement is further such that valves are activated for opening when the locking means 43 in both sides of the tank are released. Compressed air from the tank 52 will then be supplied to the pneumatic diaphragm cylinders 42, thereby lifting the weighing tank 5 for initiation of weighing.

Upon completed weighing, the parking brake being released, compressed air is supplied from the parking brake through the pipe 51 to reverse a valve 57 and thereby cutting off the connection between the pneumatic tank 52 and the pipe 53. The diaphragm cylinders 42 and the cylind-

CfRE

OMPI ers 50 of the locking means are then vented through a check valve 58.

Consequently, the weighing tank 5 is relαwered into place. In its lowermost position, the latter actuates a valve 59, thereby permitting compressed air to be supplied to the cylinders 50 of the locking means from the opposite end so that the locking means are fastened.

It applies to all embodiments that the tanker may be provided with a spirit level adapted to provide a signal of warning by inadvertent inclination of the tanker. The signal may be used for blocking the operation of the weighing system. The pipes serving for transporting milk may further be adapted for pneumatic draining so as to efficiently provide for draining of the system before another transport operation is initiated.

The invention is explained on the assumption that the weighing tank 5 during a weighing operation is lifted free of a stationary support. The operations are equally practicable if the weighing tank be stationary and the support be adapted for lowering when a weighing operation is to be carried out.

Claims

Patent Claims:

1. A method of weighing-in milk in milk tankers used for collecting milk from the suppliers of a dairy, c h a r a c t e r i z e d in that a supplier's milk is pumped into a weighing tank (5) positioned on the tanker and weighed and that the milk is subsequently pumped into a collection tank (3,4) positioned on the tanker, during the travel of the tanker to the next supplier.

2. A milk tanker for carrying out the method according to claim 1, c h a r a c t e r i z e d in that the milk truck in addition to one or more tanks (3,4) for collection of milk has a separate, preferably smaller weighing tank (5) connected to one or more weigh- ing cells (8) .

3. The milk tanker according to claim 2, c h a r ¬ a c t e r i z e d by means for releasing the weighing tank (5) during weighing from means for stabilizing the tank during travel.

4. The milk tanker according to claim 3, c h a r ¬ a c t e r i z e d in that the weighing tank (5) by weigh¬ ing means (8) is connected to a lifting device (9) .

5. The milk tanker according to claim 4, c^* h a r - a c t e r i z e d in that the weighing means (8) is form¬ ed of three weighing cells arranged as a three-point suspension.

6. The milk tanker according to claim 2, c h a r ¬ a c t e r i z e d in that the weighing tank (5) is connected to a pump (12 or 40) adapted for pumping milk in¬ to the weighing tank (5) as well as for draining said tank into the collection tank (3,4).

7. The milk tanker according to claim 6, c h a r ¬ a c t e r i z e d in that the pump (12) is reversible.

8. The milk tanker according to any one of the claims 3-7, c h a r a c t e r i z e d in that the means for releasing the weighing tank during weighing, from means for stabilizing the tank during travel are oper- o ationally connected to the parking brake system of the tanker.

9. The milk tanker according to any one of the claims 3-8, c h a r a c t e r i z e d in that the means

₅ for stabilizing the weighing tank during travel are operationally connected to the parking brake system of the tanker.

10. The milk tanker according to any one of the claims 2-9, c h a r a c t e r i z e d in that the pipe 0 system of the tanker serving for transporting milk is adapted for pneumatic draining of the pipes.

11. The milk tanker according to any one of the claims 2-10, c h a r a c t e r i z e d in that the tanker is provided with a spirit level adapted to generate a 5 control signal by inadvertent inclination of the tanker.