US3349973A

US3349973A - Receptacle filling machines

Info

Publication number: US3349973A
Application number: US560583A
Authority: US
Inventors: Robert L Smith
Original assignee: Chemetron Corp
Current assignee: SPX Corp
Priority date: 1964-02-04
Filing date: 1966-06-27
Publication date: 1967-10-31
Anticipated expiration: 1984-10-31

Description

0a. 31, 1967 R. L', SWTH 3,349,973

RECEPTACLE FILLING MACHINES Original Filed Feb. 4, 1964 4 Sheets-Sheet 1 I N VE N TOR. P056272. .sM/r/r Oct. 31, 1967 R. L. SMITH RECEPTACLE FILLING MACHINES 4 Sheets-Sheet 2 Original Filed Feb. 4, 1964 I N VE N TOR. R08 5R7: 1. SMITH Arman/ Er Oct. 31, 1967 R. SMITH REGEPTACLE FILLING MACHINES Original Filed Feb. 4, 1964 4 Sheets-Sheet 5 INVENTOR. 08527 L. SMITH Oct. 31, 1967 R. SMITH 3,349,973

RECEPTACLE FILLING MACHINES Ori ginaI Filed Feb. 4, 1964 4 Shecs-Sheet 4 I86 we INVENTOR. ROBERT L. SM/fl/ A TTOENE'Y United States Patent Ofiice 3,349,973 RECEPTACLE FILLING MACHINES Robert L. Smith, Louisville, Ky., assignor to (Ihemetron Corporation, Chicago, 11]., a corporation of Delaware Original application Feb. 4, 1964, Ser. No. 342,427, now Patent No. 3,289,712. Divided and this application June 27, 1966, Ser. No. 560,583

2 Claims. (Cl. 222-380) ABSTRACT OF THE DISCLOSURE A receptacle filling machine having a passageway for holding a supply of fluid with seals and a trap valve assembly to control flow of the fluid from, and entrance of atmospheric air into the passageway in the absence of a substantial pressure operating on the fiuid supply.

This is a division of copending patent application Serial No. 342,427, filed February 4, 1964 now United States Patent No. 3,289,712.

This invention relates in filling machines.

It is another object of the invention to provide, in a receptacle filling machine, a piston-cylinder metering mechanism including sealing means having flap or lip portions which face one another, constructed and arranged to prevent air leakage into a passageway during the intake stroke of the piston and to prevent liquid leakage out of the passageway during the discharge stroke of the piston, the sealing means being lubricated by the liquid.

It is another feature of the invention to provide valve means for a receptacle filling machine for selectively opening and closing inlet and outlet ports, with valve means having a closure portion mounted for travel into and out of the inlet port and having a resilient seal effective to prevent liquid leakage to or from the reservoir when the outlet port is open, the seal having a flap portion constructed and arranged to enter and leave the inlet port easily and to obviate damage to the seal.

It is another object of the invention to provide a discharge device, for a receptacle filling machine having a valve port housing, which cooperates with a movable valve, with a toggle clamp constructed and arranged to urge the discharge device upwardly against, and into locked position relative to, the valve port housing.

It is another object of the invention to provide, in a receptacle filling machine, valve means for selectively opening and closing inlet and outlet ports with the valve means having a closure portion movable into and out of the inlet port, with a discharge trap effective to prevent fiow out of a passageway connecting the inlet and outlet ports in a condition when the outlet port is open and the operation of the machine is interrupted, the closure portion having a resilient seal for preventing liquid leakage from a liquid supply source, through the inlet port into the passageway, through the outlet port, and through the discharge trap during such condition.

It is another object of the invention to provide a discharge trap for a receptacle filling machine which coopergeneral to the art of receptacle ates with a movable valve so that liquid leakage from a passageway leading to the discharge trap is obviated when the outlet or discharge port is open and the operation of the machine is interrupted.

It is another object of the invention to provide, in a receptacle filling machine, a piston-cylinder metering mechanism in which a piston is spaced from and guided for travel in an elongated cylinder by non-metallic wear rings, with the wear rings constructed and arranged to 3,349,973 Patented Oct. 31, 1967 in a receptacle filling machine, for selectively opening and closing inlet and outlet ports, with a passageway connecting the inlet and outlet ports and a metering mechanism, with a discharge trap formed at least partly in the valve and constructed and arranged so that when the outlet port is open and the metering mechanism ceases to discharge liquid, leakage from the passageway is obviated.

It is another object of the invention to provide, in a receptacle filling machine having a vertically movable valve, a resilient closure portion operable by the valveto open and close a discharge port so that dripping is obviated when the discharge port is closed.

These objects and other features and advantages will become more apparent from the following description and reference to the accompanying drawings, in which:

FIGURE 1 is an elevational view, mainly in section, showing a fragmentary portion of a rotary filling machine in accordance with the invention;

FIGURE 2 is an enlarged elevational view, mainly in section, showing in detail a fragmentary portion of a pistion and a wear ring and air and liquid seals which it carries, in association with a cylinder;

FIGURE 3 is an elevational view, mainly in section, showing in detail a valve with a discharge trap, and showing the valve in its lowered position;

FIGURE 4 is an elevational view, mainly in section, similar to FIGURE 3, showing the valve in its raised position;

FIGURE 5 is an enlarged fragmentary view showing a seal in extended position as when the valve is in the lowered position;

FIGURE 6 is a sectional view taken along line 6-6 FIGURE 9 is a fragmentary sectional view showing a portion of a piston provided with an alternative form of air and liquid seal, in association with a cylinder;

FIGURE 10 is an elevational view, mainly in section, showing an alternative form of discharge trap from that shown in FIGURES 1 and 3 through 8 of the drawings, with the valve shown in its lowered position;

FIGURE 11 is a view similar to FIGURE 10, but showing the valve in its raised position;

FIGURE 12 is a sectional view of FIGURE 10;

FIGURE 13 is a sectional View taken along line 13-13 of FIGURE 10;

FIGURE 14 is a sectional view taken along line 1414 of FIGURE 10;

FIGURE 15 is an elevational view, mainly in section, of a fragmentary portion of a filling machine like that illustrated in FIGURE 1, showing an alternative form of discharge trap, and showing a valve and a closure in their lowered positions;

FIGURE 16 is a View similar to FIGURE 15, but showing the valve and the closure in their raised positions;

FIGURE 17 is a perspective view showing a cup-shaped member of the discharge trap shown in FIGURES 15 and 16; and

FIGURE 18 is a sectional view taken along line 1818 of FIGURE 15.

Referring now to the embodiment of FIGURES 1 through 8 of the drawings, there is shown a fragmentary taken along line 1212 3 portion of a rotary filling machine generally indicated at 80. This type of machine is disclosed in U. S. Patent No. 2,896,676 in FIGURES 1 through 20 and in the description relating to those figures, and also in U. S. Patent No. 3,097,672.

The filling machine 80 is shown to have a bowl or reservoir 81 shown to contain a liquid L. The filling machine 80 includes a plurality of piston-cylinder metering mechanisms generally indicated at 82, only one of which is shown. Each piston-cylinder metering mechanism includes a piston 83 mounted for travel in an elongated cylinder 84. A clearance space 85 is shown to be provided between the piston 83 and the inside wall of the cylinder 84.

Spaced wear rings

86 and 87 are shown to be received in

grooves

88 and 89 in the piston 83. The

wear rings

86 and 87 are spaced apart on the piston 83 as far as is practical. The

wear rings

86 and 87, each have

adjacent ends

86 and 86", and 87' and 87", respectively, so that each of the

wear rings

86 and 87 is considered to be split. The

ends

86 and 86" are split at an angle sufiicient to cause the wear ring 86 to progress, that is, move, around the piston 83 as the piston 83 moves during its intake and discharge strokes. The angle of the split is preferably, but not necessarily, 45. The wear ring 87 also progresses around the piston 83 as the piston 83 moves, since the ends 87' and 87" are constructed like the ends 86' and 86" of the wear ring 86.

Secured to the upper end of the piston 83 is a roller 90 which rides in a cam track generally indicated at 91. The roller 90 is rotatably mounted on a stud-like screw 92 which is threadably secured to the piston 83. The cylinder 84 is provided with an elongated slot 93 which is shown to extend in a vertical direction. As the reservoir 81, the piston cylinder mechanisms 82, and their associated components rotate, the stationary cam track 91 will actuate each piston alternately upwardly to define an intake stroke and downwardly to define a discharge stroke. The piston 83 is prevented from rotating by a guide in the form of a guide block 94 which slides in the elongated slot 93. Since the

wear rings

86 and 87 are split, since there is a clearance space 85 between the piston 83 and the inner wall of the cylinder 84, and since the wear ring 86 travels to above the lower end of elongated slot 93, air is free to circulate into and out of the clearance space 85. Closely adjacent a liquid-engageable end 95 of the piston 83 there is provided sealing means generally indicated at 96 which serves to prevent air from leaking into a passageway 97, defined by a valve port housing 98, on the intake stroke of the piston 83 and to prevent liquid leakage from the passageway 97 during the discharge stroke of the piston 83. The sealing means 97 is illustrated as including a pair of

resilient U-cup seals

99 and 100 which are shown to face each other. The

seals

99 and 100 which are shown to be retained in grooves 101 and 102, respectively, formed in the piston 83. The grooves 101 and 102 are shown to be partly formed by a common ridge 103 which is of lesser radial extent than the piston 83 so that a passage 103' exists to provide liquid communication between the

seals

99 and 100. The U-cup seals 99 and 100, which extend completely around the piston 83, are provided with continuous flap or

lip portions

104 and 105, respectively. Initially, before receptacles are to be filled with a new product, the machine is operated so that each piston 83 can complete at least one discharge stroke. Upon the first discharge stroke of a particular piston 83, the lip portion 105 will enable liquid to pass from the passageway 97 into the passage 103' because during the discharge stroke the lip portion 105 is not primarily relied upon to perform a scaling function. The existence of liquid in the passage 103' will assure that the external surfaces of the

lip portions

104 and 105 will be wetted by the liquid which is being handled. After the completion of the first discharge stroke, the piston will move upwardly on its intake stroke so that the lip portion 105 will seal the 4 passageway 97 against air leakage from within the clearance space 85. During the intake stroke the lip portion 104 is not relied primarily upon to perform a scaling function.

When the machine is to be operated at relatively low speeds and/ or the material to be filled is of relatively low viscosity, the downwardly facing U-cup seal 104 alone is sufficient to seal the passageway 97 against air and liquid leakage.

As each of the pistons 83 move on their intake and discharge strokes, the inclined ends 86 and 86" and 87 and 87" of the wear rings 86 and 87, respectively, will cause the wear rings 86 and 87 to progress around the piston so that wear is evenly distributed. The wear rings 86 and 87 are preferably composed of a non-metallic material such as polytetrafluoroethylene, commercially known under the trademark Teflon.

Valve means generally indicated at is provided to selectively open and close a tubular inlet port 111 and a tubular outlet port 112. The valve means 110 includes a vertically movable valve 113 having a closure portion 114 which is movable into and out of the inlet port 111, and further includes a closure portion 115 movable into and out of the port 112. The uppermost portion of the valve means 110 is provided with a rotatably mounted roller 116 by means of which the valve 113 is raised into a raised position and is further provided with a magnetically-responsive element 117 by which the valve 113 is capable of being held in its raised position and of being lowered to its lowered position as more fully described in the above-mentioned Patent No. 3,097,672, it is to be understood that the valve 113 is capable of being held in its raised position and lowered by other and different means from that shown in that patent, as for example by a cam track as disclosed in above-mentioned Patent No. 2,896,676.

As best shown in FIGURES 3 through 5, the closure portion 114 is provided with a continuous peripheral groove 118 in which there is a resilient U-cup seal generally indicated at 119. The U-cup seal 119 is provided with a continuous flap or lip portion 120 which is at least slightly recessed at its upper end in the groove 118 as indicated at 121. The lip portion 120 is shown to extend in a direction generally toward the outlet port 112, and more specifically in a generally downward direction. When the closure portion 14 is positioned in the passageway 97 between the inlet port 111 and the outlet port 112 as seen in FIGURES 3 and S, the lip portion 120 is shown to extend radially slightly beyond the periphery of the closure portion 114. As the closure portion moves from the position shown in FIGURE 3 to the position shown in FIGURE 4, the lip portion 120 is flexed inwardly upon contact with the inner surface of the inlet port 111. Due to the fact that the upper end of the lip portion 120 is recessed in the groove 118 as indicated in 121, damage to the seal 119 is obviated. A lower surface of the groove 118 is shown to taper downwardly so that liquid trapped in the seal 119 is forced into the passageway 97. The seal 119 is particularly advantageous when the reservoir 81 holds a liquid of low viscosity; if leakage were to occur between the inlet port 111 and the closure 114 when the outlet port 112 is open and when the piston 83 ceases to complete its discharge stroke, not only could liquid drain completely out of the passageway 97, but the low viscosity liquid could also leak from the reservoir 81 through the passageway 97 and through the outlet port 112.

A discharge device generally indicated at 124 is shown to take the form of a discharge nozzle 125 depending from the valve port housing 98. The lower end of the valve port housing 98 is shown to be provided as an external flange 126, while the upper end of the discharge nozzle 125 is shown to be provided with an external flange 127 which is shown to 'be in face-to-face relationship and spaced from the external flange 126. The periphery of the external flange 126 has an outwardly and downcharge stroke, any air wardly inclined cam surface 128, while the external flange 127 has an outwardly and upwardly inclined cam surface 129. A toggle clamp 12, identical to the toggle clamp 12 in patent application Ser. No. 342,427, filed February 4, 1964, now United States Patent No. 3,289,- :712, is shown to urge the upper terminal end 131 of the discharge nozzle 125 into abutment with an internal downwardly facing seat 132 of the valve port housing 98. The internal seat 132 defines an opening 133 through which the valve 113 is capable of moving. A resilient O-ring seal 134 is shown to be received in a groove 135 in the upper end of the discharge nozzle 125 at a place closely adjacent to its terminal end 131. The upper end of the discharge nozzle 125 is shown to be received in a vertical extending annular bore 136 which terminates at the seat 132.

A part of the valve 113 is constructed and arranged to provide a discharge trap generally indicated at 140. The discharge trap 140 is slideably received in the nozzle 125 and is movable from the lowered position shown in FIGURE 3 to the raised position shown in FIGURE 4. The closure portion 114 and the discharge trap 140' are connected by a stern 141 of relatively small diameter. The discharge trap 140 terminates at its lower end at the closure portion 115. The discharge trap 140 is formed by various cut-outs in the valve 113 the component parts of which are considered to be: a vertical passage 142 which is in liquid communication with the liquid in the passageway 97; the vertical passage 142 leads into a pair of horizontal passages 143 and 144 which in turn lead into a pair of vertically extending passages 145 and 146, respectively; the passages 145 and 146 communicate with a vertically extending discharge passage 147, defined in part by the nozzle 125, by means of a pair of

passages

148 and 149, respectively. There is, of course, no discharge of liquid through the port 112 when the valve 113 is in the position shown in FIGURE 3. When the valve 113 is in the position shown in FIGURE 4 and assuming the piston 83 is in motion on its discharge stroke, liquid is discharged from the cylinder 84 by the piston 83 into the passageway 97, through the discharge trap 140, and through the outlet port 112. The path of the liquid through the discharge trap is as follows: downwardly through the vertically extending passage 142 and across the passages 143 and 144 into the vertically extending passages 145 and 146, and across the

passages

148 and 149 into and through the discharge passage 147.

Assuming that the valve 113 is in the position of FIG- URE 4 of the drawings and that the piston 83 ceases its motion during its discharge stroke, the discharge trap 140 will prevent liquid from draining from the passageway 97. Depending upon the viscosity of the liquid being handled, drainage of some or all of the liquid in the discharge passage 147 and the

passages

148 and 149 may occur. Once that liquid has drained from

passages

147, 148 and 149, further drainage is impossible since no air can enter the passages 145 and 146 to replace the liquid. The seal 119 prevents leakage from the reservoir 81 into the passageway 97 and through the discharge trap 140, and through the outlet port 112.

Assuming that at least some of the liquid has drained from the

passages

147, 148 and 149, and assuming further that the piston again moves to complete its diswill first be purged from the

passages

147, 148 and 149, and depending upon the amount of unfinished discharge movement of the piston, liquid may be dispensed through the discharge port 112. As

the closure portion 115 enters the outlet port 112 to prevent any further flow of liquid through the trap 140, an internal recess 150 begins to establish communication between the vertical passage 142 and the

passages

148 and 149 sothat any air which may be present in the

discharge passages

147, 148 and 149, will be bypassed directly into the vertical passage 142. Downwardly and inwardly inclined portion 151 which is immediately above the closure portion 115 cooperates with internal surface 152 of the nozzle 125 to pump any air back into the passageway 97. When the valve 113 is in its lowered position as shown in FIGURE 3, at least some of the air in the passageway 97 can find its way into the reservoir and to the surface of the liquid L.

Referring now to FIGURE 9 of the drawings, there is shown sealing means generally indicated at 155. The sealing means 155 differs from the sealing means 96, in that, instead of employing a pair of U-cup seals, a resilient C- cup seal is provided. The sealing means 155 is shown to have a pair of continuous lip or flap portions 104' and 105' which face each other. The lip portion 104 provides a liquid seal during the discharge stroke of a piston 83', while the lip portion 105' provides an air seal on the intake stroke of the piston 83. The piston 83' has only one groove 156 for receiving the sealing means 155. In all respects the piston 83' is identical in construction to the piston 83 and has spaced wear rings identical in construction to the wear rings 86 and 87. A fragmentary portion of a wear ring 157, which corresponds with wear ring 87, is shown.

Referring now to the embodiment of FIGURES 10 through 14, components having the same general construction, function and relative location are indicated by the same reference characters as in the embodiment of FIGURES 1 through 8, with the addition of letter a. A discharge device 124a is shown to include a discharge nozzle 160 releasably locked to a valve port housing 97a by what is shown to be a toggle clamp 12a. A valve port housing 98a is shown to have an outwardly extending continuous annular flange 161 terminating at an outwardly and downwardly extending cam surface 162. The

' valve port housing 98a has a tubular portion 163 terminating at a downwardly facing abutment face 164 disposed below the flange 161. The discharge nozzle has an external annular flange 165 at its upper end, and the flange 165 terminates at its periphery at an outwardly and upwardly inclined cam surface 166. The nozzle 160 also has an internal upwardly facing shoulder 167 which is brought into abutment with the abutment face 164 as the clamp 12a is brought into locking position. A resilient seal 168 is shown to be positioned in an annular groove 169 in the discharge nozzle 160 at a place between the upper surface of the flange 165 and the shoulder 167. The seal 168 could as well be provided in an annular groove (not shown) in the tubular portion 163 of the valve port housing 98a, if desired. A tubular member generally indicated at 170 is shown to define both an inlet port 171 and a portion of a discharge trap generally indicated at 140a. A valve generally indicated at 113a has a closure portion 114a for closing off the inlet port 171 and a closure portion 115a for closing off the outlet port 112a. The valve 1130 is provided with a passage 172 which extends across the valve 113a and communicates with a vertically extending passage 173. The tubular member 170 is provided with an opening 174 at its upper end, which pro- Vides communication between the passage 173 and a passage 175 when the valve 113a is in its raised position as shown in FIGURE 11; in that position the discharge passage 175 is in liquid communication with the port 112a. The passage 175 is defined partly by a portion of the valve port housing 98a and a portion of the discharge nozzle 160 and is further defined partly by a portion of the outer surface of the tubular member 170. When the closure portion 115a begins closing off the outlet port 112a, communication is established, via the passage 174, from the passage 175 and the passageway 97a. As the closure portion 114a has moved downwardly sufficiently to open the inlet port 171, liquid and any air that may be in the passage 175 can pass through the passage 174, through the inlet port 171 and into the reservoir 81a. Depending upon the viscosity of the liquid some of the air from the passage 175 may be drawn into the passageway 97a on the intake stroke of the piston.

Referring now to the embodiment of FIGURES 15 through 18, the same reference characters are employed to indicate components having the same general construction, function, and relative location as in the embodiment of FIGURES 1 through 8, with the addition of letter b.

The valve port housing 97b differs from the valve port housing 97 in that a depending flange portion 180 has internal threads 181. A two-part discharge device generally indicated at 182 includes a depending tubular member 183 which defines both an outlet port 184 and a portion of a discharge trap generally indicated at 185. The tubular member 183 has external threads 186 at its upper end. The discharge device 182 also includes a discharge nozzle 187 which is releasably locked by a toggle clamp 12b to the tubular member 183. The lower end of the tubular member 183 is provided with an annular external flange 188 having a downwardly and outwardly extending cam surfaces 189, while the upper end of the discharge nozzle 187 has an external flange 190 having an outwardly and upwardly inclined cam surface 191. Flat surfaces 188' of the flange 188 are engageable by a wrench to permit the member 183 to be easily tightened or removed from the valve port housing 981). A depending tubular portion 192 of the member 183 has an abutment surface 193 which is shown to be in abutment with an upwardly facing internal shoulder 194 of the nozzle 187. A resilient seal 195 prevents liquid leakage between the member 183 and the nozzle 187.

The lower end of the nozzle 187 has an inwardly and downwardly inclined annular internal surface 196 which terminates at a sharp annular discharge port 197. A cupshaped member 198 is shown to be spaced from and between the bottom at inner surface of the nozzle 187 and a depending tubular portion 199 of the member 183 to define a vertically extending passage 200 communicating with a vertically extending discharge passage 201 via passages 202 formed in the tubular member 198. The cup-shaped member 198 has a horizontally extending lower wall 203 so that liquid must pass through the discharge port 184, through the passage 200, through the passages 202, through the passage 201, and through the discharge port 197. The passages 202 exist between upwardly extending projections 204 which preferably terminate slightly short of the member 183. The cup-shaped member 198 has a plurality of, and in particular three, radially outwardly extending projections 205 which center the cup-shaped member 198 within the nozzle and which enable the cup-shaped member 198 to be supported by the upper end of the inclined surface 196. A closure gennerally indicated at 206, including a flexible resilient closure portion 206', is provided for opening and closing off the discharge port 197. The closure portion 206' has an upwardly and outwardly inclined surface 207 which is inclined at substantially the same angle as the inclined surface 196 and is adapted to form a seal upon contact with the inclined surface 196. The closure portion 206' is preferably constructed of a flexible resilient material, such as rubber, compatible with the liquid to be dispensed, so that it will conform to minor irregularities of the surface 196 and will provide an effective seal against liquid drippage. A vertically extending stern 208 is joined to the closure portion 206, for example by securing perforate plate 209 to the lower end of the stem 208 and by molding the closure portion 206' to the lower end of the stem 208 and the plate 209. The stem 208 is shown to be slideably received and guided by a central aperture 210 in the bottom wall 203 of the cupshaped member 198. The clearance between the stem 208 and the aperture 210 is only sufficient to permit the slidmovement of the stem 208. The bottom wall 203 of the cup-shaped member 198 is provided with a recess 211 at the place of the aperture 210. A hook-shaped recess 212 is provided near the upper end of the stem 208. One end of a compression spring 213 is hooked into the hookshaped recess 212 and the other end of the spring 213 nests in the recess 211. The valve 213 has a central, downwardly opening cone-shaped recess 214 into which the upper end of the stem 208 is adapted to move. The valve 11312 is capable of moving the closure 206 in a downward direction against the upward urging of the spring 213. The valve 113b is connected to the closure 206 through a lost-motion connection indicated generally at 215. When the valve 113!) moves upwardly so that the stern 208 loses contact with the valve 113b, the spring 213 is able to urge the seal upwardly against the bottom wall 203 of the cup-shaped member 198, thus completely opening the discharge port 197. When the valve 113b is in the position shown in FIGURE 16, liquid is capable of passing through the passageway 9712, through the discharge trap 185, and through the discharge port 197 assuming, of course, that the piston-cylinder metering mechanism (not shown in FIGURE 16) is moving on its discharge stroke; in this position, the closure portion 206' also provides an auxiliary seal against liquid leakage between the stern 208 and the aperture 210. As closure portion 115a of the valve 113a begins to close off the outlet port 184, the stern 208 begins to contact the valve 113b in the recess 214. As the valve 1131; continues to move in a downward direction, the valve 113k and the closure 206 will move together as a unit. When the valve 113b has moved downwardly to its lowermost position as indicated in FIG- URE 15, the closure portion 206' has closed the discharge port 197.

Other embodiments and modifications of this invention will suggest themselves to those skilled in the art, and all such of these as come within the spirit of this invention are included within its scope as best defined by the appended claims.

What is claimed is:

1. In a receptacle filling machine: an inlet port and an outlet port disposed below said inlet port, a passageway connecting said inlet and outlet ports, movable valve means for selectively opening and closing said inlet and outlet ports, means for metering liquid from said passageway when said inlet port is open and for discharging the metered liquid into said passageway and through said outlet port when said outlet port is open, and means provided in said valve means for preventing fiow out'of said passageway when said outlet port is open and said metering means ceases discharging liquid, said flow preventing means including at least one passage arranged for direct communication with said passageway at least one second passage connected to the one passage opposite the communication with the passageway, a third passage in liquid communication with the second passage, said third passage extending toward said passageway, a fourth passage connected to said third passage and extending from said third passage and a discharge passage in liquid communication with said fourth passage and extending in a direction away from said passageway.

2. In a receptacle filling machine: an inlet port and an outlet port, said inlet port leading from a source of liquid supply, a passageway connecting said inlet and outlet ports, valve means for selectively opening and closing said inlet and outlet ports, means for metering liquid from said passageway when said inlet port is open and for discharging the metered liquid into said passageway and through said outlet port when said outlet port is open, said valve means having a closure portion alternately movable from said passageway into said inlet port and from said inlet port into said passageway, a resilient seal carried by said closure portion for providing a liquid-tight seal across said inlet port, and a discharge trap leading from said passageway, said discharge trap including a first vertical passage in direct communication with said passageway, a lower horizontal passage connected to the first vertical passage at an end opposite the communication with the passageway, a second vertical passage in liquid communication with the lower horizontal passage and being extended toward the passageway, an upper horizontal passage connected to the end of the second vertical passage opposite its connection to the lower horizontal passage and a discharge passage in liquid communication with the upper horizonatl passage and extending away from said passageway for the discharge of the liquid, said resilient seal preventing leakage of liquid from said source, through said inlet port, through said passageway and through said discharge trap even when the liquid is of low viscosity.

References Cited Samuel 277205 XR Sturtevant 277205 XR Fleming 277-216 Smisko et a1. 285-365 XR Arnot 277-216 XR Lineweber 285-365 XR Miller et a1 222-380 Beckett 277205 FOREIGN PATENTS 534,453 12/1956 Canada.

WALTER SOBIN, Primary Examiner.

Claims

1. IN A RECEPTACLE FILLING MACHINE: AN INLET PORT AND AN OUTLET PORT DISPOSED BELOW SAID INLET PORT, A PASSAGEWAY CONNECTING SAID INLET AND OUTLET PORTS, MOVABLE VALVE MEANS FOR SELECTIVELY OPENING AND CLOSING SAID INLET AND OUTLET PORTS, MEANS FOR METERING LIQUID FROM SAID PASSAGEWAY WHEN SAID INLET PORT IS OPEN AND FOR DISCHARGING THE METERED LIQUID INTO SAID PASSAGEWAY AND THROUGH SAID OUTLET PORT WHEN SAID OUTLET PORT IS OPEN, AND MEANS PROVIDED IN SAID VALVE MEANS FOR PREVENTING FLOW OUT OF SAID PASSAGEWAY WHEN SAID OUTLET PORT IS OPEN AND SAID METERING MEANS CEASES DISCHARGING LIQUID, SAID FLOW PREVENTING MEANS INCLUDING AT LEAST ONE PASSAGE ARRANGED FOR DIRECT COMMUNICATION WITH SAID PASSAGEWAY AT LEAST ONE SECOND