CS264519B1 - Instrument for liquids dosing - Google Patents

Abstract

The fluid dispensing device comprises from the fluid reservoir and from the working cylinders with overflow pistons. Part of the working rollers there are drain plugs. When moving pistons down, the liquid is drawn into the space above the piston and at the same time extrudes from the space below the piston. At the reciprocating motion of the pistons, the fluid is \ t from the space above the piston to the space below the piston via controlled valves located in the piston.

Description

The invention relates to a device for dispensing liquids into packaging containers, eg in a packaging machine for forming, filling and closing packaging containers of thermoplastic materials. The device measures the dose and fills the container with fluid.

For dosing fluids, piston dispensers with a vertical or horizontal working cylinder with fluid flow control by rotary slide or spring-loaded check valves are currently used. The rotary valves are labor-intensive, spring-loaded check valves negatively affect dosing accuracy. Devices for dispensing fluids by means of measuring cylinders are also used. With these devices, the dose cannot be changed and a heavy-weight fluid container is actuated during operation. Devices which dispense by means of rotating segments are also known. These devices, like the rotary slide valves, require a minimum clearance in the friction surfaces and are therefore labor intensive. Further known are piston devices where the fluid flow is controlled by forced actuated valves located in the manifold and terminals. The manifold is a laborious part with a heavy weight.

The above mentioned disadvantages are eliminated by the fluid dispensing device according to the invention, which consists in the use in the working cylinders of through-flow pistons with through channels, which are controlled to be closed and the outlets are part of the working cylinders. This solution eliminates the manifold or connecting hose between the working cylinder and the outlet. In the dosing function, the reciprocating movement of the fluid intake in the working wars is eliminated

An example of the arrangement of the device for dispensing liquids into packaging containers according to the invention is shown in the accompanying drawings, in which Fig. 1 shows schematically the device in an overall view;

SUBJECT

A fluid dispensing device consisting of a fluid reservoir, working cylinders with pistons and a drive unit, characterized in that it consists of transfer pistons (8) provided with through channels (14) adjacent to the controlled '

and a bypass piston and an end piece.

The metering device is mounted on the horizontal bars 1 (FIG. 1) by means of a base plate 2. The horizontal bars 1 serve as a horizontal guide of the metering device during continuous operation of the machine. A fluid reservoir 5 rests on the spacing tubes 3 with a straight guide 4. The working cylinders 6 with the ends 7 are attached to the reservoir from below. and thus the dose is adjusted by the stop 13.

In the initial position of the metering device, the overflow piston 8 (FIG. 2) is at the top dead center, the overflow channels 14 of the overflow piston 8 are through. The diaphragm 15 of the terminal 7 is pressurized by the compressed air onto the outlet openings 16 and prevents leakage of fluid from the dispenser. By flowing from the reservoir 5 through the overflow piston 8, the fluid fills the space of the working cylinder 6, whereby the air is automatically vented.

Upon commissioning of the metering device, the passageways 14 in the overflow piston 8 are closed by a membrane 17 above which compressed air is supplied. Simultaneously, as pressure on the diaphragm 15 of the terminal 7 is passed, the outlet openings 16 pass through. The overflow piston 8 moves to the bottom dead center and expels the set dose of fluid. Upon reaching the bottom dead center, the diaphragm 15 of the terminal 7 closes the outlet openings 16 under the action of compressed air, the pressure on the diaphragm 17 in the bypass piston 8 ceases, and upon return movement of the bypass piston 8 fluid is transferred from above the piston to below. At the top dead center of the transfer piston 8, the membrane 15 of the terminal 7 and the membrane 17 of the transfer piston 8 change their position and the cycle is repeated.

Claims (1)

a diaphragm (17) for transferring fluid from above-piston spaces to below-piston spaces (8), wherein the working cylinders (6), including controlled closed terminals (7), are attached to the reservoir from below.