GB958985A - Container filling machine - Google Patents

Abstract

958,985. Bottling. PNEUMATIC SCALE CORPORATION Ltd. Feb. 28, 1962, No. 7873/62. Heading B8T. A liquid filling machine which may be of the rotating multiple head automatic type, a single head filler or a multiple head straight line machine, has the or each filler head comprised by a liquid inlet and a nozzle outlet and a liquid control valve; air under pressure is conducted into the container, e.g. bottle, to be filled by means which sense the height of the liquid therein when it reaches a predetermined level, such as to cut off this air flow and create a back pressure in the air conducting means whereby a control means operates the liquid control valve to discontinue flow to the bottle. The general arrangement of a rotary filler is shown in Figs. 1 and 8, wherein bottles 14 are fed from a conveyer 15 by a spider 13 to platforms 12 which are moved in a circular path and elevated into engagement with filling heads 16 moving in a corresponding path and carried by a rotary disc 50. On completion of the filling the containers are transferred by a spider 19 to a conveyer 21. The platforms are supported in a vertically adjustable manner on a driven rotary member 28 which supports the disc 50 by adjustable tie rods 68. Each plat- form is raised by a cam roll 32 engaging a stationary cam 34 which raises a rod 22. on which the platform is carried. Each filler head is supplied from a liquid manifold 132 via a line 88, and the manifold is fed from a tank 146 via lines 144, 134; the head is also supplied with low pressure air from a manifold 318 via lines 127, 124. Each head is associated with a pneumatic control unit 52 supplied with high pressure air from a manifold 214 and via a line 212. As each bottle is elevated it engages a nozzle guide 150, Fig. 2, on a plate 154 supported on the ends of rods 158 slidable in bearings 160 on the filler head nozzle block 80. In order to prevent operation of the control unit 52 in the event of no bottle being present on a platform, one of the slide rods carries a pin 168 with a sealing member 170 which seals a high pressure air escape orifice 164 only when a bottle is present. The construction of the filler head is shown in Fig. 4 and includes a nozzle block 80 with its hollow chamber 82 supplied with liquid by a line 88 and a vertically adjustable liquid control valve 104 normally urged upwardly by a spring 112 to cut off liquid flow to the bottle via a nozzle 18 and apertures 130 in a sleeve carried by a tube 118 extending from the valve. In the valve closed position the sleeve is withdrawn into the nozzle to cut off flow from the apertures. Low pressure air fed by a line 124 flows through the stem of the valve and through the tube 118 which constitutes an air nozzle. Each control unit 52, Fig. 6, includes a pneu- matically operated piston and cylinder 62, 60 to the upper end of which high pressure air is supplied whereby the piston forces the liquid valve stem downwardly to allow filling ; a spring normally urges the piston upwardly. A three way manifold 204 of the unit is fed with high pressure air by a line 212; a high pressure supply is led to a trip valve 172, a shuttle valve 174 and a diaphragm valve 178. The shuttle valve includes a slide valve 182 movable in a pressure chamber 184 into either of two positions, in one of which it allows high pressure air to flow to the piston and cylinder to open the liquid filling valve, and in the other to exhaust the high pressure air so that the piston 62 may move upwardly to allow the liquid valve to close. Movement of the slide valve is effected by reducing the pressure at either end of the pressure chamber 184. During rotation of each filling head its trip valve is operated by a cam piece 252 whereby pressure air passes to the block 166; if a bottle is present the outlet 164 from the block is closed by the member 170 and the back pressure set up is fed to a piston and cylinder 244, 246 which opens a bleed valve 238. The latter bleeds one side of the pressure chamber 184 so that the slide valve is moved to feed high pressure air to the piston and cylinder 62, 60 and thereby to open the liquid valve. When the liquid level in the bottle reaches the end of the air nozzle 118, air is bled from the opposite side of the chamber 184 via a line 284 and a bleed valve 280 opened by a piston and cylinder 288, 290, to effect evacuation of the cylinder 60 and closure of the liquid valve. Pressure air is fed through line 294 to actuate the piston and cylinder 288, 290 when the diaphragm 298 of the valve 178 is urged to the left, Fig. 6, to close a normally open high pressure air outlet at the end of a sleeve 310. Such movement of the diaphragm is effected when the liquid in the bottle closes the air nozzle 118, whereby the back pressure thus set up acts on the diaphragm. In order to ensure the closure of the liquid valve, if not effected by the low pressure supply to the bottle, the bleed valve 280 is operated by a normally closed safety trip valve 338 opened by a stationary cam piece 342 as the apparatus rotates.