US 3903938 A
Description (OCR text may contain errors)
United States Patent Osborne 1 1 Sept. 9, 1975 AND 1785.706 3/1957 Ryan 61 81 .1 141/131 FILLING FLOWABLE MATERIAL INTO 3,065,775 11/1962 Keves i. 141/131 3,457,968 7/1969 Tuma .4 141/102 OPEN TOP CONTAINERS Primary Examiner-Houston S. Bell, Jr. Attorney, Agent, or Fz'rmWilliam Anthony Drucker [57 ABSTRACT Apparatus for charging accurate amount of liquid or powder into open top containers moving continuously in a straight line comprising an elongated supply vessel means for maintaining a constant level of filling material in said vessel, a row of a plurality of constant flow discharge valves from said vessel each operable to discharge material for container filling or for return to a reservoir, an actuator for operating each of said valves to cause it to make container filling discharge, a continuously rotating cam effective on each actuator in timed relation to the continuous movement of con tainers below the discharge valves, and a container operated sensor adjacent each discharge valve and effective to prevent an actuator operating its discharge valve to cause filling discharge in the absence of a container below it.
5 Claims, 3 Drawing Figures PATENTEUSEP 9197s 3,903,938
sum 1 [1F 3 Qm nnu PATENTED 91975 3.903.938
sum 2 0F 3 PATENTED P 1975 SHEET 3 BF 3 METHOD OF AND APPARATUS FOR FILLING FLOWABLE MATERIAL INTO OPEN TOP CONTAINERS BACKGROUND TO THE INVENTION In apparatus for filling open top containers it is usual for the container to be stationary during the filling operation, and attempts have been made to move the containers as quickly as possible between filling stations to obtain high operating speeds. To avoid the disadvantages of such apparatus it has been proposed to provide in-line filler apparatus in which the containers move continuously and are filled progressively by a plurality of deliveries having ports which open sequentially as a container passes thereunder, but such apparatus is complex and gives rise to difficulties particularly when hot material is to be changed into containers.
An especial difficulty with previously proposed inline fillers, in addition to the disadvantage of having parts movable in a supply reservoir, is under and over filling of the containers due to unevenness in the rate of discharge through the various deliveries, both individually and collectively, which cannot be cured by adjustment of the rate of flow through each of the deliveries as it has been observed that the variation in discharge rate occurs due to changes in pressure of the material supply and the effect of turbulence therein due to port opening and closing.
It is also necessary to ensure that a delivery will not discharge during the time a container is not below it to avoid waste of material apart from mess and other disadvantages.
This invention relates to a method of and apparatus for filling flowable material such as liquids or powders into open top containers such as jars and cans as they move continuously in a straight line.
The object of the present invention is to provide a method of and apparatus for container in-line filling with the advantage that the containers to be filled are continuously moving and in which its deliveries are individually closed when there is no container therebelow without affecting the flow rate through the other deliveries.
A further object of the present invention is to provide container filling apparatus in which a constantly maintained head of filling material is supplied at a constant total discharge rate to progressively fill continuously moving containers through a plurality of downwardly directed discharges, opened in timed relation to the movement of the containers, by opening a by-pass discharge with the closing of each filling discharge, such that there is filling discharge during the time a container is below it and flow to the feed back at other times so achieving a constant flow rate, provision also being made for preventing each discharge valve giving a filling discharge when there is no container therebelow to cater for any gap in the sequence of containers, so that there is no waste of material nor spillage due to over-filling of containers by correct selection of the flow rate during filling discharge.
Another object of the invention is to provide container filling apparatus comprising an elongated supply vessel to which filling material is continuously fed, means for maintaining a constant level of filling material in said vessel by returning surplus material to a reservoir, a row of a plurality of constant flow discharge valves from said vessel each operable to discharge material for container filling or for return to the reservoir to maintain a constant total discharge rate through the apparatus, an actuator for operating each of said valves to cause it to make container filling discharge, a continuously rotating cam effective on each actuator in timed relation to the continuous movement of containers below the discharge valves, and a container operated sensor adjacent each discharge valve and effective to prevent an actuator operating its discharge valve to cause filling discharge in the absence of a container below it.
A still further object is to provide such apparatus with additional means for moving all the actuators together to close their associated discharge valve should the supply of containers or their continuous movement cease for any reason.
A still further object of the invention is to provide such apparatus in which each discharge valve comprises a chamber with a constantly open inlet port and two outlet ports one for container filling by downward discharge and the other feeding to a feed back conduit, the outlet ports being progressively and alternately openable by a slidable element moved by an operating rod extending through the chamber walls through liquid seals, and moved in one direction by a cam operated actuator and in the opposite direction by a spring.
The foregoing and further objects of the invention will be apparent from the description of a preferred embodiment of the invention.
DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view of the apparatus with part broken away to show internal mechanism,
FIG. 2 is an end elevation being a view on the lefthand side of FIG. I, and
FIG. 3 is a cross-sectional view on an enlarged scale to show a discharge valve and its operating mechanism.
DESCRIPTION OF PREFERRED EMBODIMENT OF THE INVENTION An elongated filling vessel or gravity feed tank I is continuously fed with filling material through a supply pipe 2 to maintain a constant head of filling material therein by a trough 3 with a discharge duct 4 leading back to a reservoir 31, such trough receiving material above the desired level.
The supply tank 1 is provided at its bottom with a row of apertures 5 each opening into a valve chamber 6 which is desirably made of stainless steel and has two outlets, one outlet 7 forming a downwardly directed discharge for filling material into a container 8 situated therebelow and the other outlet 9 opening to a return conduit 10 leading back to the reservoir 31. The outlets 7 and 9 are alternately and progressively opened and closed by a slidable valve member 11 having a flat working face, which may be coated with P.T.F.E, moving on a flat surface of the valve chamber in which the outlets 7 and 9 are formed. The valve member 11 is moved to and fro by push-rod 12, which extends through the valve chamber walls and through liquidtight seals as may be necessary, and is urged by a spring 12 in the direction to move the valve member 11 for filling to discharge through the port '7. The member I] is urged into contact with the surface of the valve chamber by the pressure of the material acting on it and is not affected by wear of its working face, nor by expansion and contraction due to change in the temperature of the material.
Each push-rod 12 is moved against its loading spring 12 by an actuator 14 shown as a rockable bell-crank lever with one limb thereof carrying a roller forming a cam follower which normally engages a contour cam 16 which rotates in timed relation to the container continuously moving means such as two worm conveyors 13, 13' dr ven in timed relation with the cam 16 by a motor M. The longer limb of the actuator 14 may directly enuage the end of a push-rod 12 to move the same on being rocked but preferably, and as illustrated, carries an adjustment screw 17 to engage the push-rod end. When the actuator 14 is rocked (clockwise as seen in FIG. 3) it moves the push-rod 12 to cause the valve 11 to close port 7 and open the port 9. The strength of the spring 12 not only maintains the end of the pushrod 12 in contact with the screw 17 but also bias the actuator 14 to maintain its roller 15 in contact with the cam 16 for movement thereby, unless such actuator is rocked by the action of either of the jacks 22, 26, which are hereafter described.
It will be appreciated that the valve arrangement above described is such that there is a constant rate flow of filling material through the valve chamber and that as the valve member 11 is moved to close the outlet port 7, as when there is no container therebelow, the other port 9 is correspondingly and progressively opened so maintaining the flow rate through the valve chamber. To vary the flow through the outlet poft 7, the adjustment screw 17 is operated so that the valve member 11 opens the port a required amount up to fully open; the constant flow rate being maintained in that while there is less than full flow through the port 7 there is also partial flow through the port 9.
In order to prevent opening of a filling discharge when there is no container below the valve chamber 6, a sensor is provided which is shown as slidable member 18 urged towards a container edge by a spring 19 and by its movement controlling the actuator 10 of a pneumatic valve 21. When there is no container 8 moving along below a valve chamber 6, the movement of the member 18 under the action of its spring 19 causes it to operate the pneumatic valve 21 which controls an air cylinder jack 22, the extension of the piston rod 23 of which effects rocking of its associated actuator 14 to cause the valve member 11 to close the port 7. Such jack 22 may be carried by a frame member 24 through which also extends an adjustment screw 25 for limiting movement of its actuator 14 and bears on the end of the adjustable screw 17.
A further air cylinder jack 26 may be provided and arranged for its piston rod 27 to act either directly or through a bell-crank lever 28 on a bar 29 lengthwise of the apparatus and effective on all the actuators 14 to rock the same to cause closure of the valve filling dis charges, and such jack 26 is made operative as by a second container sensor (not shown) to extend its piston rod 27 should the supply of containers 8 cease or stop moving and when it is desired to stop container filling by a manual control (not shown).
Initial supply of filling material may be through a conduit 30 to the reservoir 31 from which material is drawn through a conduit 32 by a pump 33 discharging to the supply pipe 2 to the tank 1. The overflow discharge duct 4 leads back into the reservoir 31 as does also the return conduit 10.
In use of the apparatus the material to be filled into the open top containers is continuously fed to the supply tank and material in excess of a predetermined level enters the trough and returns to the reservoir. The discharge valves at the bottom of the tank are operated such that as a container passes along below the row of discharge valves it receives from each of them an amount of material until at the end of its travel it is filled to a desired extent. Each discharge valve may discharge a like amount of material, although those first passed-under may discharge a larger amount than those latterly passed to ensure filling with a minimum of splash. The NO CONTAINER NO DlSCl-[ARGE oper ation avoids waste of material and the effective operation of the apparatus is not affected by operation with material at different temperatures.
1. The method of filling material into open top containers moving continuously in a straight line which consists in maintaining a constant head of filling material in a supply tank and feeding said material at a constant total discharge rate to progressively fill said continuously moving containers through a plurality of downwardly directed discharges from said tank, opening said discharges in timed relation to the movement of said containers with progressive alternate closing of a by-pass discharge with the opening of each filling discharge to achieve a constant flow rate, and preventing each discharge valve giving a filling discharge when there is no container therebelow.
2. Apparatus for in line filling material into continuously moving containers including:
a supply tank,
a material supply for continuously supplying material to said supply tank,
means for maintaining a constant level of material in said supply tank,
a row of a plurality of constant flow discharge valves in the bottom of said tank for discharging material from said tank to said containers,
a displaceable valve member within each valve,
an actuator for displacing each valve menber to terminate the discharge of material through the valve for container filling and allow discharge of material through the valves for return to said material supply, and
means for actuating said actuator in timed relationship with said moving containers to permit discharge of material from each valve for container filling only when a container is correctly aligned with respect to the valve to receive the discharge of meterial therefrom.
3. Apparatus as claimed in claim 2 in which each discharge valve comprises a chamber with a continuously open inlet port and two downwardly directed outlet ports, one of said outlet ports discharging for container filling and the other feeding to a return conduit to a reservoir, a valve member for progressively alternately opening said outlet ports, an operating rod for displacing said valve member, spring means for moving said operating rod in one direction, said actuator moving said operating rod in the opposite direction to close said outlet port to said return conduit and a continuously rotating cam effective on each actuator in timed relation to the continuous movement of containers below the discharge valves, and a container operated sensor adjacent each discharge valve and effective to justment vary extent of opening of said outlet port for container filling.
5. Apparatus as claimed in claim 3 including additional means for moving all said actuators against the loading of said spring effective on said operating rod, and a sensor effective when there is no container move ment to actuate said additional means.