DE9310942U1 - Device for separating oil and coolant mixture - Google Patents

Description

pOfta Patent Attorneys

Dipl.Phys. Ulrich Twelmeier Dipi. I ng. D.Jendryssek-Neumann Dr. phil. nat. Rudolf Bauer -1990 Dipi. I ng. Helmut Hubbuch -1991

20.07.1993 TW/Be

Meiser GmbH, D-7134 Knittlingen

Device for separating oil and coolant mixtures

Description :

The invention relates to a device for separating mixtures of oil and coolant that arise during the machining of metal workpieces by floating, with a container with an inlet for the mixture, an overflow for the oil and an outlet for the coolant.

Oil separators are known for separating oil/water mixtures. They are containers into which the mixture is introduced and left to settle for a while. The oil then has the opportunity to float because it is specifically lighter than water. It is known that

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It is best to provide an overflow in the tank so that the oil that has floated up can drain into a channel. The overflowing oil still contains water. In order to further concentrate the oil, it is also known to combine several overflow tanks to form a cascade.

When machining metal workpieces, e.g. when drilling, coolants are used to cool the workpiece and tool; these are generally aqueous emulsions. The coolants are relatively expensive, and efforts are therefore made to collect them and reuse them. However, this causes difficulties in cases where not only a coolant but also an oily or greasy lubricant is used in metal machining, because in this case it is not possible to collect the pure coolant, but only a coolant/lubricant mixture. If you want to recover the coolant from this, you have to separate it from the lubricant. The well-known oil separator cascades with a series of overflow containers arranged next to one another are too complex and therefore too uneconomical, especially for smaller metal machining companies.

The present invention is based on the object of providing a device for separating during machining

to create a system for separating mixtures of oil and coolant that arise when working on metal workpieces, which can be manufactured in a small and compact manner and thus inexpensively, and yet can separate mixtures of oil and coolant so effectively that the coolant recovered can be used directly again for metalworking.

This object is achieved by a device having the features specified in claim 1. Advantageous further developments of the invention are the subject of the dependent claims.

Due to its structure of concentric tubes, the device according to the invention is optimally compact and at the same time extraordinarily inexpensive to manufacture because it can be assembled from simple standard parts. Despite the compact structure, the device is highly effective: The mixture to be separated is allowed to flow from above into the innermost tube. In this innermost tube, a certain calming of the mixture already takes place, which, along with a sufficient flow time, is a prerequisite for the oil to be separated to float up. The mixture leaves the innermost tube at its lower end and enters the second compartment, which is formed by the annular space between the innermost tube and the next tube. In this

The liquid gradually rises through the second tube, with simultaneous separation as the oil floats up, collecting on the surface of the liquid in the second compartment. Oil that has already floated up in the innermost tube also preferably flows over into this compartment.

In order to subject the coolant, which is depleted of oil in the second compartment, to a further cleaning stage, the coolant flows below the floating oil layer into a third compartment, which is formed by the annular space between the second pipe and the third pipe that follows it. The coolant flows downwards in this annular space, with baffles preferably being installed to promote the separation process. Suitable baffles are fillers known from chemical process engineering, in particular those made of plastic or metal; they not only extend the flow path for the coolant, but also collect oil and dirt particles on them. After the cleaning process in the third compartment, the coolant leaves the third compartment through an outlet at the lower end and is so clean that it can be immediately reused as coolant. To prevent the device from running dry, the lower outlet of the third compartment is connected to an overflow which is higher than the overflow between the second and third compartments, but lower than the oil overflow which the second and third compartments have.

part preferably in common. This ensures that the oil can only drain out of the device via the overflow provided for this purpose.

The overflow, over which the floating oil drains, is most easily arranged stationary at a given height. However, the cleaning process can be accelerated by attaching the overflow to a float so that the overflow rises and falls with the liquid level within a given level range. This means that the oil can overflow even before the container is full. The range of movement of the float is conveniently limited by an upper and lower stop.

The connection from the outlet of the third compartment to the overflow for the coolant could simply be a pipe. However, the easiest way to handle the device is to surround the third pipe again concentrically with a fourth pipe, which creates the connection to the overflow for the coolant.

For a simple construction of the device, it is best if the concentric tubes all stand on a common base plate and are firmly and tightly connected to it. The transition from the first compartment to the second compartment and from the third compartment to the fourth compartment is then most easily achieved through one or more side openings in the first and third tubes close to their lower ends.

After a certain period of operation, the fillers in the third compartment are so loaded with oil and dirt that they need to be cleaned. The easiest way to do this is to take the entire device to a petrol station that is equipped with an oil separator and to spray it out with a high-pressure water jet.

The device according to the invention can be manufactured so inexpensively that it can be used economically in a decentralized manner alongside individual machines.

An embodiment of the device is shown schematically in the accompanying drawings.

Figure 1 shows such a device in a

vertical section along the central axis,

Figure 2 shows the section A-B through this device,

and
20

Figure 3 shows a floating overflow for such a device.

The device consists of a base plate 1 and four concentric pipes 2, 3, 4 and 5, which stand on the base plate 1 and are firmly and tightly connected to it. This forms four concentric compartments 7, 8, 9 and 10. The inlet 6 to the device is located at the upper end of the first compartment 7, which is connected by

a bore 11 at the lower end and a lateral overflow 12 at the upper end of the pipe 2 is connected to the second compartment 8. The second pipe 3, which separates the second compartment 8 from the third compartment 9, is shorter than the other three pipes 2, 4 and 5. The liquid rising in the compartment 8 can therefore overflow via the upper end of the pipe 3 into the third compartment 9, in which packing elements 13 are arranged. The compartments 8 and 9 have a common overflow 14, which can be regulated by a diaphragm 15 using a handle 16.

Oil 17 overflowing from the first compartment 7 and floating in the second compartment 8 and the third compartment 9 leaves the device through the overflow 14. The cleaned coolant emulsion leaves the third compartment through three star-shaped holes 18 and thus reaches the fourth compartment 10, in which it rises up to an overflow 19, from where it can reach a storage container.

Instead of allowing the floating oil to drain over a fixed overflow, a floating overflow can also be provided in the area of the compartment 8. Such an overflow is shown - detached from the rest of the device - in Figure 3. It consists of a pipe 21 protruding from the base plate 1, on which a hollow cylindrical floating body 22 is guided, in which an immersion pipe 24 concentric with the pipe 21 is fastened, forming an annular gap 23, which extends telescopically into the

Pipe 21 is immersed. The displacement path of the float is limited at the bottom by a spacer 24, which keeps the float 22 at a distance from the base plate 1 so that it does not stick to the base plate, and it is limited at the top by a retainer 25, which ensures that the oil can still overflow safely even at the maximum liquid level. The overflowing oil runs into a hole (26) in the base plate 1 and from there to an external hose connection 27, through which it can be drained.

The device can be made of metal or plastic.

Claims (9)

Expectations: 1. Device for separating during machining of mixtures of oil and coolant arising from metallic workpieces by floating with a container with an inlet for the mixture, with an overflow for the oil and with an outlet for the coolant, characterized in that the container is connected by concentrically arranged tubes (2, 3, 4, 5) in at least is divided into three compartments (7, 8, 9, 10), of which the innermost (7) has the inlet (6) for the mixture at the top and a flow connection with the adjacent second compartment (8) at the bottom,
15 that the second compartment (8) has a first overflow (20) into an adjoining third compartment (9), that the second and third compartments (8, 9) have a second overflow (14) for floating oil, which is higher than the first overflow (20) from the second (8) to the third compartment (9), and that the third compartment (9) for the coolant has an outlet (18) at the bottom, which is connected to a third overflow (19) which is higher than the first (20) but lower than the second overflow (14). 2. Device according to claim 1, characterized in that the connection between the outlet (14) of the third compartment (9) and the third overflow (19) is formed by a fourth concentrically arranged compartment (10). 3. Device according to claim 1 or 2, characterized in that the third compartment (9) contains filling bodies (13). 4. Device according to one of the preceding claims, characterized in that the innermost compartment (7) has a fourth overflow (12) to the second compartment (8) and that the fourth overflow (19) is higher than the other overflows (14, 19, 20). 5. Device according to one of the preceding claims, characterized in that the tubes (2, 3, 4, 5) stand on a common base plate (1). 6. Device according to one of the preceding claims, characterized in that the overflow for the floating oil is arranged floatingly. 7. Device according to claim 6, characterized in that the overflow is connected to a floating body (22) or is designed as a floating body. 8. Device according to claim 7, characterized in that a vertical overflow pipe (9) is provided, on which the floating body (22) connected to an immersion pipe (24) immersed in the overflow pipe (21) is guided. 9. Device according to claim 8, characterized in that the overflow pipe (21) opens into an outwardly leading bore (26) in a base plate (1) of the device.