RS54484B1 - DOSAGE UNIT - Google Patents

Abstract

Dosing unit for liquid or paste media with reservoir (1), at whose throat (2) is mounted a dosing pump (5) having two parts (11, 16), wherein the hollow cylindrical first part (11) of the dosing pump is mounted (5) connects to the throat (2) and has at the suction port a first non-return valve (6) with a first valve body (7), the second portion (16) forming the piston of the dosing pump (5) provided with an external actuator outlet ( 17) for the stroke (h) of the dosing pump (5) extends in the first part (11) and at the discharge port which is in line with the suction port, there is a second non-return valve (8) with a federally loaded second valve body ( 9) and wherein both non-return valves (6, 8) open in the same direction and the distance (a) between the two valve bodies (7, 9) is variable, characterized in that a first valve body (7) is made in the suction port. as the opening stop for the other valve body (opposite the exhaust outlet) 9) .The application contains 6 more patent claims.

Description

The invention relates to a unit for dosing liquid or pasty media with a tank, on the neck of which a dosing pump is placed, which has two parts, whereby the hollow cylindrical first part of the dosing pump is connected to the throat and has a first non-return valve with a valve body at the suction opening, and the second part, which forms the cylinder of the dosing pump equipped with an external accessory for handling the start of the dosing pump, extends movably in the first part, and on the exhaust opening located in in the same line with the intake opening has a second non-return valve with primarily a damper supplied by the second valve body, and both non-return valves open in the same direction and the distance between the two valve bodies is variable. In the following, the first non-return valve will be designated as the intake valve and the second non-return valve as the exhaust valve.

See also WO 82/04203 as more recent prior art.

From FR 10 64 626, a tank with a pump for dosing not more closely defined liquid media is known, whereby the tank stands upside down during discharge. Both valve bodies are spherical and placed on both ends of the rod supplied with a damper, whereby in the state of rest the second valve on the exhaust port is closed and the first valve on the suction port is open, so that the pump chamber is filled with medium. When the second part of the dosing pump that forms the cylinder is raised, then the first valve closes and the second one opens so that the portion contained in the pump chamber can flow out.

Under the action of the return spring, the second part that makes up the chamber is then returned to its initial position, whereby the second valve closes and the first opens, so that the pump chamber is filled again.

The rigid connection of both valve bodies leads to inaccuracies in dosing, since both valves are not mutually optimally coordinated, where the fluidity properties of the medium play a role. However, a rigid connection has the advantage that, for example, when air enters the pump chamber, the exhaust valve opens reliably when the pressure generated in the pump chamber is insufficient.

The invention set itself the task of creating a dosing unit composed of a tank and a dosing pump connected to it, where inaccuracies in dosing caused by valve disturbances were avoided. This is achieved by having the first valve body placed in the intake opening act as an opening stop for the second valve body placed in the exhaust opening lying on the opposite side.

In this way, both valve bodies work without mutual influence during a significant part of the pump movement, and direct connection between the two valve bodies occurs only in case of failure before the end of the movement, when the other valve body is stuck in the closed position and forcefully opens the exhaust valve. The compressed air enclosed in the pump chamber can thus escape from the dosing pump. This is exactly the advantage when using the pump for the first time. The connection of the two valves ensures that when the exhaust valve dries out, as may be the case when the pump is idle for a long time, the second valve body opens mechanically. The closing force of the intake valve corresponds to the required opening force of the exhaust valve.

As an advantage, it is further provided that the second valve body has a shaft that axially protrudes into the dosing pump, the free end of which is at a distance from the first valve body.

A support for the damper can be made on the stem, which then fixes the second body of the valve in the closed position so that the exhaust valve is sealed and the medium cannot subsequently drip.

Further details and advantages of the proposed invention are explained in more detail below based on the description of the sketches with reference to the exemplary embodiments presented in the drawings. In them it shows: Fig. 1 An oblique view of a dosing unit according to the invention with

covered dosing pump,

Figure 2 Longitudinal section through the dosing pump at rest,

Figure 3 Longitudinal section through the dosing pump after dispensing the portion

medium,

Figure 4 Longitudinal section through the dosing pump in the error condition

closed position of both valve bodies,

Figure 5 Longitudinal section through the dosing pump according to Figure 4 before forced opening of the exhaust valve.

The discharge unit, especially for the application of the head in a dispenser for the discharge of liquid or pasty media, includes a rigid, refillable tank 1 with a dosing pump 5 placed on its neck 2, which is covered by a protective cap 3 until use, as shown in Figure 1. The dosing pump includes two essential parts 11, 16, of which the first part 11 is placed on the neck 2 of the tank 1, especially inseparably glued or welded, if the tank 1 and the dosing pump 5 are made of plastic material. One such dosing unit is replaced by a full one after emptying. However, it is also conceivable for the dosing pump 5 to be releasably mounted on the tank 1, so that the exhaust unit can be refilled and used.

The first part 11 of the dosing pump 5 is made as a hollow cylinder and in the area of connection with the tank a suction opening is provided to which a suction valve is assigned in the form of the first non-return valve 6. For this in the sketches of the upside-down setting in the first non-return valve, the first valve body 7 provided in the sketches is made spherical and is freely held in the valve cage 12 which has several supports with the ends of the protrusions protruding inward. The valve seat is spherical in shape. Due to the force of gravity, the first non-return valve 6 in the shown stationary position in Figure 2 is open. Other suitable suction valves are, for example, flap valves, umbrella valves or beak valves.

The second part 16 of the dosing pump 5 constitutes its piston and is mounted movably against the spring 21 in the hollow cylindrical first part 11, so that the pressure space 20 of the dosing pump can be changed. Opposite the suction opening in the first part 11, a discharge opening is provided in the second part 16, to which a discharge valve is assigned in the form of the same directed, i.e. outwardly opening, second non-return valve 8. The second non-return valve 8 has a valve body 9 that expands conically and has a stem 10 that extends axially into the pressure space 20. The stem ends at a variable distance a, which is less than the stroke h of the dosing pump to the first body valve 7. The stem 10 has an annular shoulder, so the closing spring 22 in the second part 16 is coupled between the annular shoulder and the inner side of the valve seat. In the resting position shown in Figure 2, the second non-return valve 8 is therefore hermetically closed. The closing spring 22 determines the opening pressure of the dosing pump 5.

The pressure space 20 is reduced by raising the second part 16 which forms the piston. The device used for this is not the subject of the invention, whereby in Figure 2 the movable sleeve 25 is provided only in the dispenser placed on the head, which engages around the second non-return valve 8 on the external outlet 17 on the second part 16 of the dosing pump 5. Another, in a given case replaceable, in the form of a washer, jet regulator 18 or the like can be provided below the outlet opening. controlled the speed of discharge or dispersion of the outgoing medium.

If the movable sleeve 25 is raised from the position according to figure 2, the closed medium in the pressure space 20 is pushed out through the second non-return valve 8 through the discharge hole, since the first non-return valve 6 closes the way to the tank 1. At the end of the movement, the stem 10 of the second valve body 9 rests on the first valve body 7. If the dosing pump 5 in the compressed position, as shown in figure 3, is released again, it is released with the help of the feder 21, the pressure space 20 increases, and at the beginning of the return stroke based on the position of the stem 10 on the valve body 7 through the still open second non-return valve 8 in the area of the valve, the remaining residue of the medium is sucked back into the pressure space 20, so that subsequent dripping is avoided. After this short moment, the stem 10 moves away from the first valve body 7 during the continued return stroke, so that on the one hand the second non-return valve 8 can be closed and on the other hand the first non-return valve 6 can be opened. Thus, the medium is now sucked from tank 1 until the return stroke is completed and the state of rest according to figure 2 is reached.

The arrangement of the stem 10 on the first valve body 7 helps to eliminate or reduce malfunctions, which may result from the second valve body 9, especially with the help of the closing feather 22, remaining stuck in the discharge opening. These functional disturbances are dependent on the type and consistency of the contained medium and the simultaneous entry of air into the pressure space 20, primarily during the first use, shortly before the contents exit, or during prolonged non-use due to the sticking of the second body of the valve 9 in the discharge opening. The lifting of the second part 16 that makes up the piston, in such a case, will only empty the pressure space 20 if the enclosed air can be compressed so much that the pressure is sufficient to release the second glued valve body 9. If the proportion of air is too high, then it is even conceivable that the second valve body will remain in its seat, and renders the dosing pump unusable, since each stroke only compresses the air and each return stroke relaxes it but does not push it.

A disturbance of this type caused primarily by the closing of the air can be seen from figure 4. At the beginning of lifting, the first non-return valve 6 is closed, and the first valve body 7 is pressed into the valve seat, while the second valve body 9, which is additionally raised by the spring 22, has not moved down, so that the second non-return valve 8 also remains closed. By further lifting, the pressure in the pressure chamber 20 can be sufficiently increased, so the second non-return valve 8 opens, after which further dosing procedures can take place in the desired manner. But if this is not enough, the stem 10 of the second valve body 9 after about two-thirds of the stroke h - the valve body 9 lies higher and closer to the first valve 6 than when it would open - hits the first valve body 7. This moment is represented in figure 5. The remaining part of the stroke h forcibly translates the valve body 9 into the open position according to figure 3, so that the dosing pump 5 becomes functional again and it remains, and on the next use it discharges a full portion.

In order for air to enter the tank 1, which should not be flattened by external pressure, when the medium from the pressure space 20 is sucked out, a vent channel 14 is provided in the area fixed on the throat 2 of the first part 11 of the dosing pump 5, which extends into the tank 1 and is equipped with another non-return valve, especially a duckbill valve.

The spring 21 for returning the second part 16 of the dosing pump 5 can be absent if it, not more closely described user device for the dosing pump 5, of which the moving sleeve 25 is sketched in Figure 2, has a return spring or the like, and the moving sleeve 25 forcibly guides the moving outlet 17 in both directions.

Claims (6)

1. A unit for dosing liquid or pasty media with a tank (1), on the neck (2) of which is placed a dosing pump (5) which has two parts (11, 16), whereby the hollow cylindrical first part (11) of the dosing pump (5) is connected to the throat (2) and has a first non-return valve (6) with a first valve body (7) on the suction opening, while the second part (16) which forms the piston of the pump for dosing (5) equipped with an external outlet for starting (17) for the stroke (h) of the dosing pump (5) is movably extended in the first part (11) and at the discharge opening which is in line with the suction opening has a second non-return valve (8) with primarily a damper loaded with a second valve body (9) and both non-return valves (6, 8) open in the same direction and the distance (a) between the two valve bodies (7, 9) is variable, indicated by the first valve body (7) is placed in the intake opening, made as an opening limiter for that, the second valve body (9) is placed in the opposite exhaust opening. 2. Dosing unit according to claim 1, characterized in that the second valve body (9) has one shaft (10) axially protruding into the dosing pump (5), the free end of which is in the gap (a) towards the first valve body (7). 3. Dosing unit according to claims 1 or 2, characterized in that the second non-return valve has a conical valve seat and a spherical valve body (9). 4. Dosing unit according to one of claims 1 to 3, characterized in that the first valve body (7) is made spherical. 5. Dosing unit according to claim 4, characterized in that for head application the first valve body (7) is held in a valve cage (12) provided in the first part (11) of the dosing pump (5). 6. Dosing unit according to one of claims 1 to 5, characterized in that the reservoir (1) is non-compressible and that the first part (11) has an air inlet channel (14) with a non-return valve.