JPS6242764Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a liquid purification device that electrostatically purifies insulating liquids such as oil, and in particular to a purification device that has been improved to increase purification efficiency in response to viscosity changes. be.

A conventional device of this type is constructed as shown in FIG. In FIG. 1, reference numeral 1 denotes a main body of a liquid purification device, in which positive electrodes 2 and negative electrodes 3 are arranged alternately, and a dust collector 4 is provided between the electrodes. Reference numeral 5 denotes a high voltage power supply, which supplies a high voltage of about 10 kV between the positive electrode 2 and the negative electrode 3. It is also equipped with a pump 6 and a valve 7 for introducing the liquid to be purified, and the liquid to be purified in the tank 8 is introduced from the lower part of the main body through a hose 9, passed through the dust collector 4, and then from the upper part of the main body. The water is circulated through the hose 10 and returned to the tank 8 for purification.

However, if the liquid purification capacity of this device is expressed as the amount of liquid that purifies a certain degree of contamination per unit time, as shown in Figure 2, as the viscosity of the liquid increases, the purification capacity increases. Capacity decreases. To give a concrete example of this, for example, if you use the same equipment to purify and compare oils with different viscosities, the oil with a higher viscosity will have an extremely lower oil purification ability than the oil with a lower viscosity, which may cause confusion to the user. The sex was hot. Furthermore, even if the oil is the same, the viscosity will change greatly if the oil temperature changes, so for example, in the case of hydraulic oil for a molding machine, oil at around 40°C can be purified as is, and oil at room temperature around 20°C can be purified. Compared to the case of purification, the latter has a considerably higher viscosity, so the oil purification capacity is reduced to a fraction of that, resulting in a reduction in the amount of purification.

In addition, low-viscosity oils generally contain a large amount of metal fine particles, such as cutting oils and electrical discharge machining oils, and their oil purification ability is rather high, concentrating near the entrance of the dust collector 4. As the dust is collected, the insulation resistance between the positive and negative electrodes decreases, causing too much current to flow and lowering the voltage, which may make electrostatic dust collection impossible or shorten the life of the dust collector 4. There were also drawbacks such as being dark.

In order to eliminate the drawbacks of the conventional example, the present invention automatically reduces the flow rate when the viscosity of the liquid to be purified is high to increase the purification ability, and increases the flow rate when the viscosity is low to collect dust. To provide a liquid purification device designed to extend the lifespan of the body. Hereinafter, embodiments will be described in detail with reference to the drawings.

FIG. 3 shows an embodiment of the present invention.
The same reference numerals as in FIG. 1 indicate the same parts, and 11 is a flow rate control pipe provided at the liquid delivery port of the purifier main body 1. As shown in FIG. 4, this flow rate control tube 11 has a plurality of thin tubes 12 loaded inside it in a bundle, and the pressure loss changes depending on the viscosity of the liquid flowing therethrough. That is, the higher the viscosity of the liquid, the greater the pressure loss in the flow control tube 11, and therefore the lower the flow rate. Conversely, the lower the viscosity of the liquid, the lower the pressure drop and the higher the flow rate.

Here, when the relationship between the flow rate of liquid flowing through the purification device and the purification capacity is shown in Fig. 5, curve A is for relatively low viscosity oil, curve B is for relatively high viscosity oil, and curve C is for relatively high viscosity oil. is for an oil with a viscosity between A and B. As is clear from this figure, when the flow rate is the same, as explained in Fig. 2, the higher the viscosity of the oil (curve B), the lower the purification ability. Purification ability can be increased by reducing the flow rate. On the other hand, if the oil has a low viscosity (curve A) and contains a lot of dust such as cutting chips, the pressure loss in the flow control pipe 11 is low, so the flow rate is high, and the purification ability is reduced.
Since the dust is not concentrated near the entrance of the dust collector 4 and the dust is collected substantially uniformly throughout the dust collector 4, the life of the dust collector 4 can be extended.

The reason why the purification ability increases as the flow rate decreases is that the residence time for dust in the liquid to be sucked into the dust collector 4 by the electrostatic field between the electrodes becomes longer, and therefore the time required for the dust to pass between the dust collectors becomes longer. This is because the probability of adsorption to is increased.

Note that the same effect can be obtained by providing a viscosity detector and a pump that controls the flow rate in conjunction with this detector in place of the flow rate control pipe 11 in this embodiment.

As explained above, according to the present invention, by reducing or increasing the flow rate of the liquid flowing through the purification device in response to the high or low viscosity of the liquid to be purified, purification ability is ensured even when the viscosity is high. On the other hand, for materials with low viscosity and generally containing a lot of cutting waste, the purification ability is appropriately reduced so that the dust collector collects the dust evenly and the electrostatic effect is maintained. This has great effects such as being able to extend the life of the dust collector.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a conventional example, FIG. 2 is a diagram showing the relationship between the viscosity of a liquid to be purified and liquid purification ability according to a conventional example, and FIG. 3 is a configuration diagram of an embodiment of the present invention. Fourth
This figure shows the internal structure of the flow rate control pipe, and FIG. 5 is a diagram showing the relationship between the flow rate and purification capacity of liquids to be purified having different viscosities. 2... Positive electrode, 3... Negative electrode, 4... Dust collector,
5...High voltage power supply, 6...Pump, 8...Tank,
11...flow control tube, 12... thin tube.

Claims (1)

[Claims for Utility Model Registration] (1) In a device that has an electrostatic purification means inside and purifies an insulating liquid such as oil by passing it through, when the viscosity of the insulating liquid is high, the passing flow rate is reduced. A liquid purification device characterized in that a flow rate control means for increasing the flow rate when the viscosity is low is provided in the outflow path from the device. (2) Utility model registration claim (1), characterized in that the flow rate control means comprises a detector that detects the viscosity of the insulating liquid, and a pump that controls the flow rate based on the detection result. Liquid purification device as described. (3) The flow rate control means is comprised of a flow rate control tube that includes a plurality of thin tubes bundled together and constitutes one section of the flow path for the insulating liquid. ) The liquid purification device described in item ).