GB2146704A - Apparatus for sucking up liquids - Google Patents

Abstract

The invention relates to an apparatus for sucking up a liquid and collecting the liquid in an oil drum or like vessel, which in one case has at least two closable openings (3,4) to which an ejector pump (5) and a suction hose (6) are removably attached. Since it is difficult to decide when the vessel begins to be full, a reliable float valve arrangement (11) must be arranged for automatically closing off the suction apparatus. The latter is built into a suction pipe stub (10) which is connected to the pump (5) and projects into the vessel (1). The float valve device (11) is accordingly protected by the pipe stub (10) so that it cannot be damaged by ungentle handling of the pump (5) when the latter is not attached to a vessel (1) for the moment. The invention also includes a unit including both suction pipe stub and liquid conduits for application to a single orifice in a container. (See Fig. 2). <IMAGE>

Description

SPECIFICATION Apparatus for sucking up liquids The present invention relates to an apparatus for sucking up liquids, e.g. heavily contaminated, inflammable or corrosive liquids, and collecting them in a container. It is already known to connect vacuum generating means to containers, thereby to provide a sub-pressure in the container for collection of liquids through a suction pipe connected to the container. So-called ejector pumps are used in such cases, and these pumps can be connected to existing compressed air systems, e.g. such as are found in workshop. Previously known apparatus for sucking up liquid is relatively heavy and difficult to handle.

Furthermore, the sub-pressures which are required in the liquid collection vessel are built up relatively slowly with small pumps, which results in a relatively time-comsuming filling operation. If there is the possibility of building up a heavy sub-pressure for rapidly filling the container, other problems immediately occur, since overfilling and accompanying damage to the ejector pump easily occurs.

The present invention relates to a solution, inter alia of the above-mentioned problems. A distinguishing feature of the invention is that the ejector pump itself is provided with a pipe stub thrusting into the vessel and including a float valve for closing off the pipe stub when a predetermined liquid level has been reached in the vessel. It is customary to connect the pump to an orifice in the container in question, and connect a suction pipe or hose to a second orifice in the container for sucking up the liquid. However, in accordance with the invention there is also proposed a combined unit enabling the application of the entire unit to one outlet on a container.

The characterizing features of the present invention will be apparent from the following claims.

The invention will now be described in detail with reference to embodiments illustrated on the accompanying drawings.

Figure 1 illustrates how an apparatus in accordance with the invention is applied to an orifice in the end wall of an oil drum.

Figure 2 illustrates a further embodiment of the apparatus in accordance with the invention, seen in perspective.

Figure 3 is a section of a detail of the ejector pump itself.

The oil drum 1, illustrated in the Figures, is placed upright so that one end wall 2 is facing upwards. This end wall is conventionally provided with a small threaded orifice 3 and a larger threaded orifice 4. The ejector pump 5 is screwed into the small orifice, and a suction hose 6 is connected to the larger orifice with the aid of a coupling member 7 screwed therein. The pump is driven by compressed air, which is supplied to the pump through a compressed air hose 8 connected to a compressed air line 9. The pump is provided with a suction pipe stub 10, into which a float valve 11 is built, it thus being well protected against unintentional damage during handling when the pump is not attached to the oil drum 1. The implementation of the float valve will be more clearly apparent in conjunction with what is illustrated in Fig. 3.

Normaliy, the ball is namely resting against an abutment such that air can freely pass in into the pipe 10 and around the ball 11 without the latter being moved.

However, as soon as liquid comes into the tube 10, the ball floats upwards and closes off the air evacuation path.

In supply compressed air to the pump 5, air is sucked through the pipe stub 10 and out through an outlet opening 12, a sub-pressure thus being created in the container 1, providing that the opening of the suction pipe 6 is immersed in a liquid 1 3. Said liquid is now sucked rapidly up into the container 1. When the latter is filled with liquid up to a given level, marked by a dashed line 14, the ball of the float valve floats up from its rest, as previously mentioned, and positively closes the evacuation duct of the pipe stub 10 so that liquid is no longer sucked up.

The ejector pump, which is of very effective implementation, as will be seen from the Figures, provides very rapid and effective evacuation of air in the container on which it has been mounted. This results in that liquid is very rapidly sucked into the container, resulting in rapid total filling. The arrangement of the illustrated float valve is thus of extreme importance in preventing the intrusion of liquid, e.g. unclean liquid, which can destroy the ejector pump. In practical tests it has been found that if the pump is connected to a compressed air network operating at about 5-6 bar, and normally found in workshops, over 200 liters of liquid can be sucked up in to a head of about 2 meters in about 1 minute.

Many containers and oil drums have only one usable orifice which can be utilized for the above purposes discussed above. As already mentioned, an oil drum has a small threaded orifice 3 and a larger filling and emptying orifice 4, as is clearly apparent from Fig. 1. The small orifice 3 is usually intended for venting purposes, but it is quite often the case that this orifice has a very tight plug which cannot be loosened, e.g. due to corrosion. It is thus of importance that the existing opening can be used by itself. An embodiment is illustrated in Fig. 2, where all that needs to be fitted to the container is a pump unit in accordance with the invention. The unit contains an ejector pump as well as passage and connection means for the liquid which is to be sucked up.The unit illustrated in Fig. 2 comprises a casing 1 5 including an unillustrated ejector pump, an air inlet pipe stub 1 6 and an outlet with silencer 1 7. Four nozzle tubes 1 8 project from the casing 1 5 into the silencer 17, and the function of these tubes will be described in conjunction with Fig. 3. The casing is further provided with an inlet pipe 19 for liquid which is sucked up, and a hose 20, illustrated with dashed lines, may be connected to the pipe 1 9. Downwardly, the casing 1 5 is provided with a thread 21 e.g. for connection to an oil drum.

A pipe stub 22 projects out within the area defined by the thread 21, this stub being intended for communication with the pipe 1 9 carrying the liquid which is to be sucked in.

An evacuation pipe 23 is mounted to one side of the pipe stub 22 and is substantially equivalent to the pipe stub 10 in Fig. 1.

The unit now described is adapted for screwing on to such as an oil drum, after which a compressed air hose 8 is connected to the pipe stub 1 6 and a suction hose 20 to the inlet pipe 1 9. When the pump is put into operation by supplying air through the pipe stub 16, a sub-pressure will be provided in the container, via the evacuation pipe 23, liquid then being sucked through the hose 20 into the pipe 1 9 and out through the pipe stub 22 into the container itself. When a given liquid level has been reached in the container, the float valve closes off the pipe 23, thus inhibiting further evacuation of air.

Fig. 3 is a section through one of the nozzle devices in the ejector pump. As will be seen from Fig. 2, there are four such mutually parallel devices included in and forming the active part of the pump. In Fig. 3, the part of the device in communication with the compressed air inlet pipe stub 1 6 is denoted by 16' and the one in connection with the nozzle pipes 18 by 18'. The casing 15 itself is depicted somewhat simplified in Fig. 3, but functionally surrounds the nozzle devices.

Compressed air thus comes in from the pipe stub 1 6 and in through a duct 24 to a nozzle part 25. Said duct opens out in the nozzle part into a chamber 26 enclosed by the casing 1 5. Also included in the casing is a nozzle part 27 projecting from the portion 18' into the chamber 26. The duct 28 in said nozzle part 27 has a larger diameter than the duct 24, and one end opens out into the chamber 26 while the other end is in communication with one of the nozzle tubes 18, as will be seen from Fig. 3, the pipe 23 is inserted in the wall of the casing 15 and opens out into the chamber 26. The pipe includes a column 29 against which a float ball 30 rests in a cup-shaped recess. There is a valve seating 31 arranged for coaction with the ball 30 above said ball.The tube 23 is provided with a plurality of air inlet orifices 32, and two arrows 33 and 34 illustrate the path of the air round the ball when it is in a position for evacuating air. As will be seen by the arrows 35, existing air is sucked out from the space 26, i.e. air which has come in through the tube 23, and is driven through the duct 28 by compressed air coming from the compressed air unit through the duct 24.

When liquid comes into the tube 23, the valve ball 30 will float up to its seating 31 and will be retained in this position by the continuing air evacuation force until operation ceases. Apparatus according to Fig. 3 has been found in practice to be extremely effective and can achieve the emptying which has been previously mentioned in conjunction with Fig. 1.

It should be emphasized that the pump 5 and pipe 10 with the valve 11 in Fig. 1 can be implemented as proposed in Fig. 3.

A plurality of embodiments within the scope of the invention can naturally be envisaged in respect of the casing 1 5 as well as pipe stubs and nozzles. It is also conceivable to have more than four nozzle devices, e.g. for providing sub-pressures in very large tank installations.

By such expedients as forming the tube 22 long enough to reach down to the bottom of a container, suction of liquid in the container as well as emptying of the liquid in the container can be easily provided by arranging valves for closing off the ducts 28 in the associated nozzle devices, pressure being generated in the chamber 26 instead of vacuum, such that the container is put under pressure and the liquid in the container is forced out through the pipes 22 and 1 9 and further by the hose 20.

Claims (8)

1. -1. Apparatus for sucking up liquids, e.g.

   heavily contaminated, inflammable or corrosive liquids, and collection of such in a container with one or more preferably closable orifices, characterized in that in one orifice (3) of the container (1) there is removably attached an ejector pump (5), adapted for evacuating air in the container (1) such as to create a sub-pressure, the container (6, 19, 20) being adapted for communication with a liquid (1 3) and the pump (5) being provided with a pipe stub (10, 23) projecting into said container and including a float valve (11, 30, 31) for closing off the air evacuation path when a predetermined liquid level (14) has been reached in the container.
2. 2. Apparatus as claimed in claim 1, characterized in that the float valve (11, 30, 31) is built into the pipe stub (10, 23) such that it is protected against mechanical damage, and mounted (29) such that the valve body (11, 30) is not entrained by the air current during the evacuation of air, but when the given liquid level (14) has been reached said body is caused to float up against a valve seating (31) in the air path (10, 23).
3. 3. Apparatus as claimed in claim 2, characterized in that the float valve comprises a ball-shaped body (30) arranged such that in its position of rest it abuts against a holder (29) arranged in the pipe stub (23), in which position the body (30) is unactuable by the air current (34).
4. 4. Apparatus as claimed in any of the preceding claims, characterized in that the pipe stub (10, 23) is removably mounted on the pump (5, 15).
5. 5. Apparatus as claimed in any of the preceding claims, characterized in that the pump is built into a casing (15) including said pipe stub (23) and a liquid flow path (19, 22) opening out into a further pipe stub (22) parallel with said pipe stub (23), both pipe stubs being disposed within an area of the casing (15) provided with attachment means (21) for attaching the casing to a container orifice (4).
6. 6. Apparatus as claimed in claim 5, characterized in that the casing (15) is provided with inlet means (16) and outlet means (1 7, 18) for compressed air as well as connection means (1 9) for a liquid suction conduit (20).
7. 7. Apparatus as claimed in any of the preceding claims, characterized in that the pump comprises two nozzle parts (25, 27) mounted mutually in register in an evacuation chamber (26), one nozzle part (25) having a duct (24) for compressed air, said duct having a diameter less than the duct (28) of the other nozzle part (27) which communicates with outlet conduits in the form of projecting nozzle pipes (18).
8. 8. Apparatus as claimed in claim 7, characterized in that a plurality of nozzle devices are disposed parallel in the evacuation chamber (26) each opening out into its perspective nozzle tube (18) projecting out from the casing (1 5), a silencer (17) being arranged in connection with said nozzle pipes.