US2649996A

US2649996A - Valve and suction cutoff mechanism

Info

Publication number: US2649996A
Application number: US158306A
Authority: US
Inventors: Bertie S Harrington
Original assignee: Armour and Co
Current assignee: Armour and Co
Priority date: 1950-04-26
Filing date: 1950-04-26
Publication date: 1953-08-25
Anticipated expiration: 1970-08-25

Description

Aug. 25, 1953 B. s. HARRINGTON 2,649,996

VALVE AND SUCTION CUTOFF MECHANISM Filed April 26, 1950 3 Sheets-Sheet l I N VEN T OR.

'TRNEX Aug. 25, 1953 B. s. HARRINGTON VALVE AND SUCTION CUTOFF MECHANISM 3 Sheets-Sheet 2 Filed April 26, 1950 INVENTOR.

BY ,M 6 4 ATTORNEY.

1953 B. s. HARRINGTON I 649,996

' VALVE AND SUCTION CUTOFF MECHANISM Filed April 26, 1950 3 Sheets-Sheet 3 i225? fdfi z/ g w BY CM! 6. K7,?

ATTORNEY:

Patented Aug. 25, 1953 VALVE AND SUCTION CUTOFF MECHANISM Bertie S. Harrington, Chicago, Ill., assignor to Armour and Company, Chicago, 111., a corporation of Illinois Application April 26, 1950, Serial No. 158,306

9 Claims.

This invention relates to valve and suction cut-ofi mechanism. The mechanism is particularly useful in controlling the discharge of fluid or semi-solid material which is discharged from a nozzle or a plurality of nozzles, the operation of th valve being eifective for producing a suction at the end of the nozzle so that at the end of the filling operation the material clinging to the end of the nozzle is drawn back into the valve or discharge conduit.

Various devices have been employed for the cutting off of liquid or semi-solid material clinging to the end of discharge nozzles. Such cutoffs are of great importance in order to secure a uniform filling of each container. However, mechanical cut-offs often become clogged and further tend to introduce partially dried material into the containers. Such structures are also unsatisfactory in that they require separate and expensive mechanism for accomplishing the cut-ofi function.

An object of the present invention is to provide a simple valve structure which is effective not only for controlling the fiow of the material in the filling operations but also in creating a suction in timed relation to the filling steps so as to draw back into the discharge conduit the material clinging to the end of the conduit or nozzle. Yet another object is to provide in a valve structure means for enlarging a chamber in the valve so as to create a suction at the discharge end of the conduit or nozzle at the end of a filling step. A further object is to provide a spool valve structure effective for alternately creating suction upon two discharge conduits so that after alternate filling steps the material about the end of the nozzle is drawn back into the conduit or valve chamber. A further object is to, provide, in combination with measuring means for supplying a semi-solid or fluid material to containers, valve means for controlling the flow of the material to and from the measuring means and from thence to discharge conduits, the valve structure providing also means for creating a suction at the end of each filling step and sucking back material at the end of the conduit or nozzle. Other specific objects and advantages will appear as the specification proceeds.

The invention is shown in illustrative embodiments by the accompanying drawings, in which Figure 1 is a perspective view of apparatus embodying my invention; Fig. 2, a broken vertical sectional view of the valv mechanism, measuring cylinder and associated conduits; and Fig.

2 3, a view similar to Fig. 2 but showing another embodiment of the invention.

In the illustration given in Figs. 1 and and as more particularly shown in Fig. 2, l designates the incoming pipe or conduit leading from a pump or other source of pressure. The material may consist of lard, molten cheese, or other fluid 0r semi-solid types of materials which are to be discharged into containers. The apparatus illustrated is adapted for the filling of containers alternately, the containers being carried below the filling nozzles II on separate conveyor tracks (not shown).

I provide a valve housing l2 in which there is centrally provided a valve chamber l3 equipped with sealing lands M. A spool valve I5 is mounted for reciprocal movement and is equipped with valve discs l6 and l! adapted to alternately making sealing contact with the spaced lands I4 so as to close and open their passages. The incoming conduit 10 communicates centrally with the chamber [3 through a passage [8, as shown more clearly in Fig. 2.

Below the valve housing I2 is a measuring cylinder housing [9, and the two housings are connected so as to provide the passages and 2|. The housing [9 provides a cylinder chamber 22 in which is mounted a floating piston 23 having projections 24 at the ends thereof.

The passage 211 communicates with a port 25 at one end of the cylinder chamber 22, while the passage 2| communicates with a port 26 at the other end of the chamber 22. Thus when fluid material is supplied under pressure at one end of the piston 23, it causes the piston to move in the opposite direction and to force fluid material out of the other end of the chamber, as will be described more fully hereinafter.

Each end of the cylinder housing 19 is provided with a spring-urged plunger 21 adapted to actuat a contact 28 to open or break an electrical circuit, as desired. The electrical circuit, in turn, is equipped with solenoids or other means for actuating an air valve for the supplying of air for the actuation of the spool valve I5, as will be later described. The electric circuit and valve mechanism is shown in detail in my copending application, Serial No. 35,193, filed June 25, 1948, now Patent No. 2,620,960, dated December 9, 1952.

Any means may be employed for the actuation of the spool valve I5. In the specific illustration given in Figs. 1 and 2, the housing I2 is equipped at each end with an end plate 29 which is apertured to receive a compressed air tube 39. The

housing also provides an air chamber 3| in which there is mounted a floating piston 32. The piston 32 is adapted to engage on its inner side an extension 33 of the spool valve [5. Th stem extension 33 is preferably provided with a bearing or sealing ring 34 which is received within a reduced recess 35 provided by the housing.

The pistons 32 may be of any desired construction. I prefer to provide each piston centrally with an annular recess 36 and on each side of the recess I prefer to employ sealing rings or gaskets 3'! formed of resilient material such as rubber, etc. It is important that air not come in contact with the lard which is being dispensed, and the sealing ring 3'! is eifective for preventing the flow of air into the annular recess 35. The sealing ring 31 on the opposite side is also effeo tive in preventing the flow of lard into the annular recess. In order to take care of any possible leakage of either of the materials into the recess, I provide an outlet port 38 through the housing and communicating with the annular recess 36. A conduit 39 communicates with the passage 38 for the drawing off of any such material that may leak into the annular recess 35.

The passages connecting the inlet pipe H) with the ends of the measuring cylinder 22 have already been described. When the material is discharged from the measuring cylinder 22, it flows back through the same passage 29 or 2 I by which it entered the cylinder, and the valve housing i2 provides separate discharge passages through which the material may be discharged. The passage 2|, when material is being discharged there from, will be connected by the valve to the outlet passage 40, while the passage 25 will be con nected with the outlet passage 4|. The outlet passage 40 communicates past a control block 42 with a discharge conduit 43, while the passage ii communicates through a similar control block 42 with a discharge passage 44.

The valve housing provides on the inner side of each of the pistons 32 a suction chamber 45. At the lower end of the suction chamber 45 is a discharge passage 46 communicating with the chamber 45 and with the filling nozzle or conduit end ll. Thus we have a discharge conduit leading from the outlet port of each measuring cylinder to the nozzles l I and the suction chambers 45 are interposed in these discharge conduits. When the valve parts and the piston 32, which forms, in effect, a part of the valve, are in the position shown at the right hand side of Fig. 2, the valve chamber 3| is in a contracted position and is of reduced size or capacity, while when the parts are in the position shown on the left hand side of Fig. 2, the chamber 45 is enlarged or in its expanded condition and such expansion creates a suction upon the discharge nozzle therebelow, tending to suck back into the conduit material clinging to the end of the nozzle.

The control blocks 42 may be of any suitable type or construction. In the illustration given, the blocks 42 are each urged outwardly by a spring 41 and each is provided with a cut-away portion 48 at its inner end, so that when the material forces the block outwardly, there is provided an orifice through which the lard, etc. is sprayed into the

passage

43 or 44. Such spraying or atomization redistributes air through the lard and gives the proper air content for the lard, thus increasing its whiteness. The atomizer blocks 42 are not necessary and may, if desired, be omitted, any suitable means being provided for closing the outlet passage or the outer end 4 of the valve chamber 45. In operation, the atomizer blocks 42 form a seal for the outer end of

passage

43 or 44 when the material is not being discharged into these passages. A handle 41a is provided for adjusting the tension on spring 41.

Operation In the operation of the machine, lard or other material is fed through pipe [0 under pressure. Air pressure is supplied through pipe 30 to one end of the valve housing. In Fig. 2, the pressure is shown applied to the right hand side of the housing and the piston 32 at this end is moved to the left, forcing the valve I5 and the opposite piston 32 to the left. This causes the lard to flow through passage 20, as indicated by the arrow, into the chamber on the left hand side of piston 23. Piston 23 thus is moved to the right and forces material upwardly through passage 21, the valve chamber I3, and out through passage 40, past the block 42 and into the discharge passage 43. The material continues to flow through the chamber 45, which is of reduced capacity, and out through the discharge nozzle H. At the conclusion of the filling step, the piston 23 has, through its extension 24, moved the plunger 2i outwardly to operate the contact 28, thus causing the valve mechanism to reverse the air flow and the piston 32 on the left hand side of the housing is moved to the right, causing the chamber 45 on the right hand side to enlarge and create a suction on the discharge nozzle, thus drawing the material back into the nozzle and valve chamher. In the next filling operation, this material which is drawn back into the valve chamber 45, will be discharged into the container below the nozzle.

The passage 44 at the left hand side of the valve housing is shown in its enlarged condition and illustrates the size of the chamber immediately after the filling operation so that suction is being established upon the nozzle. It will be noted that the block 42 seals the outer end of the discharge passage and the sudden enlargement of chamber 45 therebelow creates the suction upon the nozzle. However, even if block 42 were not used, the spool valve 15 would close passage 4 I.

In the modified form of structure shown in Fig. 3, the parts are substantially the same as those already described in connection with Fig. 2, except that in this modification the valve pistons 32a are actuated manually by plungers 49. If desired, the plungers 49 may be connected through links 50 and 5! to the foot-operated pedal or other manually operated part.

The cylinder housing I9a is also a simpler structure since there are no means required for actuating valves, etc. One end of the cylinder may be provided with a threaded adjustment member 52 for limiting the stroke of the piston 23a and thus controlling the amount of material discharged from the measuring cylinder. In other respects, the structure is as described with respect to Fig. 2.

While I have shown the valve mechanism employed in connection with a special filling device and measuring cylinder, it will be understood that the valve structure may be employed in connection with the dispensing of liquids or semi-solids supplied through different types of dispensing devices, suction being supplied through the valve means illustrated and drawing back material clinging to the outer end portion of the nozzle or outlet pipe. The valve device may be actuated by hand power, air

power, vacuum means, or electrical means, and such substitution of power means is obvious.

While in the foregoing specification, I have set forth specific structures in considerable detail for the purpose of illustrating the embodiments of the invention, it will be understood that such details of structure may be varied widely by those skilled in the art without departing from the spirit of my invention.

I claim:

' 1. In a filling device having a pair of spaced discharge conduits and passages for supplying material under pressure to said discharge conduits, a valve housing providing a central chamber for the connecting of said conduits, a spool valve mounted in said chamber and provided with valve means for closing and opening said passages, said housing also providing valve chambers at the ends of said valve, each of said chambers being interposed in one of .said discharge conduits, a piston substantially filling one end portion of each chamber, said housing providing at the inner side of each chamber a recess of reduced diameter adapted to receive a reduced portion of the valve, means for reciprocating said pistons and thereby said valve, whereby when said valve is moved in one direction, one of said chambers is reduced in size while the other of said chambers is enlarged and when moved in the other direction, the opposite chambers, respectively, are reduced and enlarged, and means for alternately closing and opening the conduit at the inner end of each chamber.

2. In a machine adapted to fill containers with measured charges of fluid material and including a measuring cylinder having ports at the ends thereof, a floating piston mounted in the cylinder to slide back and forth between the ends, passage forming means connected to receive the material under pressure, a unitary valve mechanism controlling the fiow from said passage into and out of both ends of said cylinder consisting of a housing interposed between the passage and said cylinder, a spool type valve mounted in the housing to slide back and forth between two positions, adapted when in one position to establish communication between the passage and one of the ports and open the other port, and when in its other position to establish communication between the passage and said other port and open said one port, discharge conduits communicating through said valve with the ports of said cylinder, said valve housing providing an enlarged valve chamber interposed in each of said conduits, and extending outwardly beyond the ends of said spool valve, and a piston within each of said enlarged chambers cooperating therewith to enlarge the portions of said chambers communicating with said discharge conduits when said pistons are moved outwardly, the ends of said spool valve shiftably engaging said pistons so that the shifting of said spool valve toward either of said chambers is accompanied by a simultaneous enlargement of the chamber, thereby creating suction at the discharge end of the conduit communicating with the enlarged chamber.

3. In a machine adapted to fill containers with measured charges of fluid material and including a measuring cylinder having ports at the ends thereof, a floating piston mounted in the cylinder to slide back and forth between the ends, passage forming means connected to receive the material under pressure, a unitary valve mechanism controlling the flow from said passage into and out of both ends of said cylinder consisting of a housing interposed between the passage and said cylinder, a spool type valve mounted in the housing to slide back and forth between two positions, adapted when in one position to establish communication between the passage and one of the ports and open the other port and when in its other position to establish communication between the passage and said other port and open said one port, discharge conduits, equipped with nozzles, communicating through said spool valve with the ports of said cylinder, said housing providing valve chambers at the ends of said valve and providing also a recess of reduced diameter at the inner end of each chamber, said valve being provided in each of said chambers with an enlarged outer portion and a reduced inner portion, said reduced inner portion being adapted to being received in said recess when the valve is moved towards said recess, whereby to reduce the size of said chamber, and said enlarged portion being movable outwardly away from said recess to enlarge said chamber as the valve is moved towards said enlarged portion.

4. In apparatus of the character set forth, a valve casing providing a cylindrical flow chamber and inlet and outlet passages communicating with one end portion of said chamber, a slideably mounted valve in said casing and having an end portion extending into said chamber, and a cylindrical piston mounted in the outer end of said chamber and adapted to be movable forwardly into engagement with said valve, means for introducing compressed air into the outer end of said chamber, said piston having an annular recess in the outer periphery thereof, and sealing rings in the periphery of said cylinder and on either side of said recess, said housing being provided With a vent therethrough communicating with the annular recess of said piston, the portion of said chamber within which said piston reciprocates having imperforate Walls except for said vent, whereby material leaking into said annular recess past said sealing rings can be exhausted through said vent.

5. In a filling device having a discharge conduit, a valve housing interposed in said conduit and providing a chamber having an inlet end portion and an outlet end portion spaced therefrom by an intermediate chamber portion, said end portions each having two ports, one of said ports in each end portion communicating with said discharge conduit, a separate conduit providing a flow passage between the other two ports so that discharge material must flow successively through both end portions of said chamber, a valve mounted for reciprocation in said chamber and equipped intermediately with a sealing member cooperating with said intermediate chamber portion to separate said inlet and outlet chamber portions, said valve also having portions reciprocating within sadi inlet and outlet chamber portions, the portion of said valve Within said inlet chamber portion cooperating therewith to close said inlet chamber portion between the two ports therein when said Valve is shifted toward said outlet chamber portion, and the'portion of said valve within said outlet chamber portion cooperating therewith to enlarge the volume of said outlet chamber portion as said valve is moved toward said outlet chamber portion, whereby when said valve is shifted toward said outlet chamber portion the flow of material through said inlet chamber portion is terminated and at the same time suction is created upon the discharge end of said conduit.

6. The structure of claim 5 in which there is interposed in said separate conduit a spring urged check valve adapted to allow material to flow from the inlet end portion of said chamber to the outlet end portion of said chamber while preventing flow in the opposite direction so that the suction efiect created by the enlargement of said outlet end portion is directed solely into the discharge end of said conduit.

7. In a dispensing device having a pair of discharge conduits through which material is discharged under pressure, a valve housing interposed in said conduits and providing spaced chambers having inlet and outlet end portions, each chamber being interposed in one of said conduits and having two ports in each end portion thereof, one of said ports in each end portion communicating with said discharge conduits, separate conduits providing flow passages between the other two ports of said chambers so that discharge material must flow successively through both end portions of said chambers, and a spool valve mounted for reciprocation in all of said chambers and having a plurality of spaced flow-directing enlargements cooperating with said chambers to terminate the fiow from the inlet end portion to the outlet end portion of one of said chambers while at the same time enlarging the outlet end portion of the same chamber for creating suction upon the discharge conduit communicating with said enlarged outlet chamber portion.

8. An air pressure actuated back suction device for use in a fluid dispensing machine having a discharge conduit, comprising a housing interposed in said conduit and providing a chamber having inlet and outlet ports in one end portion communicating with said discharge conduit, a piston slidably mounted in the other end portion of said chamber, means for admitting compressed air into the end of the cylinder on the other side of said piston from said ports for moving said piston toward the end of said chamher having said ports, a reciprocally mounted member of smaller diameter than said piston and engaging said piston on the same side as said ports to move said piston away from said ports and enlarge the end portion of said chamher having said ports, thereby creating back suction on the discharge end of said conduit,

said piston having an annular recess in its outer I periphery, and sealing rings on either side of said annular recess, said housing being provided with a vent communicating with said recess for removing any air or fluid material leaking into said recess past said sealing rings, whereby said compressed air is prevented from entering the end portion of said chamber containing said fluid material and said fluid material is likewise prevented from entering the end portion of said chamber containing said compressed air.

9. In a machine adapted to fill containers with measured charges of fluid material and including a measuring cylinderhaving ports at the ends thereof, afioating piston mounted in the cylinder to slide back and forth between'the ends, passage forming means connected to receive the material under pressure, a unitary valve mechanism controlling the flow from said passage into and out of port ends of said cylinder consisting of a housing interposed between the passage and said cylinder, a spool valve mounted in the housing to slide back and forth between two positions, adapted when in one position to establish communication between the passage and one of the ports and open the other port, and when-in its other positionto establish communication between the passage and said other port and open said one port, discharge conduits communicating through said valve with the ports of said cylinder, said valve housing providing a valve chamber interposed in each of said conduits, and means carried by said spool valve for enlarging each chamber after the filling operation therethrough to create suction at the discharge end of the conduit communicating with the enlarged chamber, the means carried by said spool valve for enlarging each chamber consisting of separate pistons reciprocally mounted at each end of said spool valve and in alignment therewith so as to be contacted by an end of said valve for movement enlarging said chamber, whereby the problem of machining said spool valve and pistons is greatly simplified since said spool valve and pistons can be centered for reciprocation on slightly different lines.

BER'TIE' S. HARRINGTON.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 335,855 Toole Feb. 9, 1886 400,401 Gutzkow Mar. 26, 1889 693,921 Stickney Feb. 25, 1902 2,007,156 Burrell July 9, 1935 2,150,760 Cozzoli Mar. 14, 1939 2,352,490 Meyers June 27, 1944 2,491,826 Meyers et a1. Dec. 20, 1949 2,525,295 Harrington Oct. 10, 1950 2,620,960 Harrington Dec. 9, 1952 FOREIGN PATENTS Number Country Date 117,797 Switzerland Dec. 1, 1926 521,504 Great Britain May 23, 1940