Coolant treatment device

Abstract

To efficiently filter the coolant. [Solution] The coolant system 10 includes a flow path 11 provided in a tank 1 where coolant C is stored, a secondary filtration device 4 that takes the coolant out of the flow path and filters it, an outlet 3 that takes the coolant out from the downstream end 11D of the flow path and sends it to the secondary filtration device, and a resupply unit 5 that returns the coolant filtered from the secondary filtration device to the upstream 11U of the flow path, so that the coolant flows back through the flow path and the secondary filtration device.

Description

Technical Field

[0001] The present invention relates to a coolant processing device.

Background Art

[0002] Conventionally, a coolant processing device for removing foreign substances such as chips and cuttings from a coolant (cutting oil) used for cutting in a machine tool has been known (for example, Patent Documents 1 and 2).

[0003] The coolant processing devices of Patent Documents 1 and 2 include a tank for storing the coolant, and the coolant is recirculating in the tank. The coolant from which foreign substances have been removed and purified in the coolant processing device is sent to the machine tool and reused for cutting.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] In a conventional coolant processing device, sludge composed of cuttings and the like easily accumulates on the wall surface (bottom wall, side wall, etc.) of the tank. It is difficult to collect the sludge deposited in the tank by a filtration device. Furthermore, with conventional coolant treatment systems, if sludge accumulates in the tank, a separate operation is required to recover the sludge, and this recovery must be performed periodically. Failure to perform this operation can lead to nozzle clogging and reduced pump performance, so there was a demand to eliminate this and improve work efficiency. In addition, failure to recover sludge shortens the lifespan of the coolant, increases the amount of coolant discarded, and potentially increases the environmental impact, so there was a demand to solve this problem as well.

[0006] One of the objectives of the present invention is to provide a coolant treatment apparatus that can suppress the accumulation of sludge in the tank and efficiently filter the coolant. Furthermore, one of the objectives of the present invention is to prevent nozzle clogging and pump performance degradation, improve the coolant regeneration rate, extend the coolant's lifespan, reduce the amount of coolant to be discarded, and improve the efficiency of the disposal process. [Means for solving the problem]

[0007] (1) The coolant processing apparatus of the present invention is A flow path provided in a tank where coolant is stored, A secondary filtration device that extracts and filters the coolant from the aforementioned flow path, An extraction unit that extracts coolant from the downstream end of the aforementioned flow path and sends it to the secondary filtration device, A resupply unit that returns the coolant filtered from the secondary filtration device to the upstream end of the flow path, Equipped with, The coolant is recirculated through the aforementioned flow path and the aforementioned secondary filtration device. This resolved the above issues. (2) The coolant processing apparatus of the present invention is as described in (1) above, The downstream end of the aforementioned channel is narrower than the upstream end. It is possible. (3) The coolant treatment apparatus of the present invention is as described in (1) above, The downstream end of the aforementioned flow path has a curved R-shaped wall at the connection point with the side wall. It is possible. (4) The coolant treatment apparatus of the present invention, in the above (1), The downstream end of the aforementioned channel has a curved R-shaped wall surface at the connection point with the bottom wall. It is possible. (5) The coolant treatment apparatus of the present invention is as described in (1) above, The extraction section has a width approximately equal to that of the downstream end of the flow path. It is possible. (6) The coolant treatment apparatus of the present invention is as described in (1) above, A supply unit for supplying coolant from the primary filter is connected to a position upstream of the downstream end of the aforementioned flow path. It is possible.

[0008] According to the configuration described in (1) above, while the coolant is recirculating in the flow path and secondary filter, the coolant containing sludge is removed through the outlet, the entire amount of coolant recirculating in the flow path is filtered by the secondary filter, and the entire amount of coolant recirculating in the flow path is returned to the upstream end of the flow path. As a result, the coolant at the upstream end of the flow path contains almost no sludge. In other words, almost the entire amount of sludge-containing coolant supplied to the flow path from the primary filter can be regenerated to a reusable level. Even if the regenerated coolant is reused for precision cutting in machine tools, the coolant can be filtered efficiently to such an extent that it does not affect the machining accuracy at all. Furthermore, because sludge can be removed in the secondary filtration system, sludge hardly accumulates in the tank's flow path, and there is almost no need to recover sludge from the tank. Therefore, the interval between cleaning and maintenance of the coolant treatment system can be significantly extended, greatly improving the operational efficiency of the coolant treatment system. Furthermore, it can prevent clogging of piping and nozzles, and a decrease in pump capacity in the coolant treatment system. It can extend the lifespan of the coolant, allowing for the continued use of clean coolant and improving work efficiency by reducing the number of disposal tasks. In addition, it can reduce the load on the coolant pump used for recirculating the coolant, or allow for the miniaturization of the pump itself. Therefore, the amount of coolant waste can be reduced, and the environmental impact of the coolant treatment system can be reduced.

[0009] Furthermore, the coolant used for sludge removal may not contain large-particle foreign matter such as chips or metal shavings, or it may contain only very small amounts. In cases where it is known in advance that the coolant does not contain large-particle foreign matter, the coolant processing apparatus of the present invention can send the coolant to be processed directly to the secondary filtration apparatus without passing through the primary filtration apparatus. In this case, the coolant to be processed is supplied from a machine tool or the like to the flow path via the secondary filtration apparatus. Therefore, in the coolant processing apparatus of the present invention, the secondary filtration device can perform the initial filtration process, or the primary and secondary filtration devices can be used interchangeably. Furthermore, in the coolant processing apparatus of the present invention, it is possible to not have a primary filtration device, or to have a primary filtration device but operate only the secondary filtration device without using the primary filtration device.

[0010] According to the configuration described in (2) above, when the coolant stored in the flow path recirculates, the flow velocity increases downstream, where the flow path is narrower than upstream. As a result, sludge contained in the coolant does not accumulate and is sent to the secondary filtration device, where most of the sludge can be removed. Furthermore, the wider width at the upstream end of the flow path compared to the downstream end makes it easier to install pumps for extracting coolant to machining centers and the like.

[0011] According to the configuration described in (3) above, when taking out the coolant containing sludge through the take-out part, since the side wall corner part near the take-out part is a curved surface, it is possible to prevent the sludge from accumulating in the flow path. As a result, in the total amount of the coolant flowing back through the flow path, it is possible to filter with the secondary filtration device to remove the sludge and prevent the sludge from remaining in the tank.

[0012] According to the configuration described in (4) above, when taking out the coolant containing sludge through the take-out part, since the bottom wall near the take-out part is a curved surface, it is possible to prevent the sludge from accumulating in the flow path. As a result, in the total amount of the coolant flowing back through the flow path, it is possible to filter with the secondary filtration device to remove the sludge and prevent the sludge from remaining in the tank.

[0013] According to the configuration described in (5) above, when taking out the coolant containing sludge through the take-out part, since the take-out part is approximately equal to the flow path width, it is possible to suck up the coolant from the take-out part over almost the entire width of the bottom wall. As a result, it is possible to prevent the sludge from accumulating in the flow path. In the total amount of the coolant flowing back through the flow path, it is possible to filter with the secondary filtration device to remove the sludge and prevent the sludge from remaining in the tank.

[0014] According to the configuration described in (6) above, in the supply part of the flow path where the coolant is flowing back, the contaminated coolant is supplied from the primary filtration device to the flow path and flows toward the downstream end where the entire amount is taken into the secondary filtration device. As a result, it is possible to remove almost all of the sludge with the secondary filtration device.

Effect of the Invention

[0015] According to the present invention, it is possible to efficiently filter the coolant, prevent nozzle clogging and reduction in the capacity of the pump, improve the regeneration rate of the coolant, extend the life of the coolant, and reduce the amount of waste coolant, and it is possible to achieve the effect of providing a coolant treatment device.

Brief Description of the Drawings

[0016] [Figure 1] It is a schematic perspective view showing a first embodiment of a coolant processing apparatus according to the present invention. [Figure 2] It is a schematic side view showing upstream and downstream ends of a flow path in a first embodiment of a coolant processing apparatus according to the present invention. [Figure 3] It is a schematic top view showing the flow of coolant in a first embodiment of a coolant processing apparatus according to the present invention. [Figure 4] It is a schematic top view showing another example in a first embodiment of a coolant processing apparatus according to the present invention. [Figure 5] It is a schematic top view showing a second embodiment of a coolant processing apparatus according to the present invention.

Embodiments for Carrying Out the Invention

[0017] Hereinafter, a first embodiment of a coolant processing apparatus according to the present invention will be described based on the drawings. FIG. 1 is a schematic perspective view showing a coolant processing apparatus in the present embodiment. FIG. 2 is a schematic perspective view showing a downstream end of a flow path in the coolant processing apparatus of the present embodiment. In the figure, reference numeral 10 denotes a coolant processing apparatus.

[0018] As shown in FIG. 1, the coolant processing apparatus 10 according to the present embodiment includes a tank 1 in which a coolant C is stored, a water flow generating unit 2, a taking-out unit 3, a secondary filtration device 4, a re-supply unit 5, a primary filtration device 6, and a supply unit 7. The coolant processing apparatus 10 is a device that recovers and purifies sludge from the coolant used for cutting in a machine tool MC such as a machining center. The purified coolant is sent to the machine tool MC and used for cutting again. The coolant processing apparatus 10 is, for example, installed beside the machine tool MC.

[0019] The primary filtration device 6 includes a chip conveyor that removes and transports chips and other debris from the coolant C sent from the machine tool MC to the tank 1, and a drum filter that prevents chips and other debris from flowing into the tank 1. The coolant C that flows from the machine tool MC through the primary filtration device 6 to the tank 1 from the supply unit 7 contains sludge consisting of chips and other debris that are finer than chips. The chip conveyor is not shown in the figure.

[0020] Tank 1 may be referred to as a tank or the like. Tank 1 has a flow path 11 through which coolant C flows. The flow path 11 is formed, for example, by partitioning the inside of Tank 1 with wall material or the like. In this embodiment, the flow path 11 has an annular shape, and specifically, it has a rectangular outline when viewed from above. A primary filtration device 6 is positioned in the central inner part of the rectangular flow path 11 when viewed from above. In this embodiment, the direction in which the flow path 11 circulates when viewed from above is called the circumferential direction. The coolant C circulates along the annular flow path 11, and in this embodiment, it circulates clockwise in Figure 1.

[0021] The flow path 11 has a pair of side walls 11a that are spaced apart from each other and facing each other, a bottom wall (bottom) 11b that is connected to the lower ends of the pair of side walls 11a and faces upward, and a partition wall 11c. The pair of side walls 11a and the bottom wall 11b constitute the wall surface of the flow path 11. The partition wall 11c is formed to divide the flow path 11 at least at one point and completely stop the flow of the coolant C. The partition wall 11c is a dead end in the flow path 11 when viewed along the horizontal plane. The flow path 11 has straight sections 12 that extend in a straight line when viewed from above, forming the four sides of a rectangle, and corner sections 13 that connect the ends of adjacent straight sections 12 in the circumferential direction. Multiple straight sections 12 and corner sections 13 are provided. The straight sections 12 and corner sections 13 are arranged alternately in the circumferential direction.

[0022] Of the pair of side walls 11a located at the corner portion 13, the outer side wall 11a has an inner R-shaped wall 11a1 that forms a smooth concave curved surface when viewed from above, i.e., an R-shape. In other words, the outer side wall 11a of the corner portion 13 has an inner R-shaped wall 11a1 that is made of a concave curved surface. The four straight sections 12 have a left straight section 12a, an upper straight section 12b, a right straight section 12c, and a lower straight section 12d in Figure 1. In the left straight section 12a, the coolant C flows upward. In the upper straight section 12b, the coolant C flows to the right. In the right straight section 12c, the coolant C flows downward. In the lower straight section 12d, the coolant C flows to the left.

[0023] The lower straight section 12d has a narrower flow path width compared to the left straight section 12a, the upper straight section 12b, and the right straight section 12c. Here, the flow path width is the width in the direction perpendicular to the flow direction of the flow path 11. The flow path width is the cross-sectional area of ​​the flow path 11 when the depth of the coolant C is the same. The flow path width is the flow rate of the coolant C. Therefore, the flow velocity F is greater in the lower straight section 12d compared to the left straight section 12a, the upper straight section 12b, and the right straight section 12c.

[0024] A partition wall 11c is provided in the lower straight section 12d, as shown in Figures 1 and 2. The right side of the partition wall 11c of the lower straight section 12d is the downstream end 11D. The left side of the partition wall 11c of the lower straight section 12d is the upstream end 11U. The flow of the coolant C in the flow path 11 is completely separated by the partition wall 11c. The partition wall 11c may be lower in height than the pair of side walls 11a, but it is set to a height such that the coolant C does not flow beyond the partition wall 11c.

[0025] At the downstream end 11D, an inner R-shaped wall (R-face wall) 11a2 is formed between the partition wall 11c and the side wall 11a connected to the partition wall 11c, which has an R-shape when viewed from above, i.e., a concave curve shape. Similarly, at the downstream end 11D, an R-shaped wall 11b2 is formed between the partition wall 11c and the bottom wall 11b connected to the partition wall 11c, which has an R-shape when viewed from the side, i.e., a concave curve shape. Due to the R-shapes of these R-face walls 11a2 and R-face walls 11b2, coolant C does not accumulate around the partition wall 11c at the downstream end 11D.

[0026] An outlet section 3 is located near the downstream end 11D. The outlet section 3 is connected to the secondary filtration device 4. A coolant pump 3a is connected above the outlet section 3. The outlet section 3 is the piping that serves as the suction port for the coolant pump 3a. The coolant pump 3a is connected to the secondary filtration device 4. The outlet section 3 extracts coolant C from near the downstream end 11D. The coolant pump 3a sends the coolant C extracted from the outlet section 3 to the secondary filtration device 4. The lower end of the outlet section 3 is located close to the bottom wall 11b near the downstream end 11D. The diameter of the outlet section 3, viewed from above, is approximately equal to or slightly smaller than the width of the flow path 11 at the downstream end 11D.

[0027] Near the downstream end 11D, a supply unit 7 is connected upstream of the outlet unit 3. Viewed from above, the supply unit 7 is connected from the inside of the rectangular flow path 11 to the lower straight section 12d. A primary filtration device 6 is connected to the supply unit 7. Coolant C containing sludge is supplied from the supply unit 7 to the lower straight section 12d.

[0028] Coolant C, sucked from the outlet 3 by the coolant pump 3a, is sent to the secondary filtration device 4. The secondary filtration device 4 separates the coolant C from the sludge by the action of centrifugal force, etc. The separated sludge is collected in a drain cup or the like and is collected by an operator, for example, at regular intervals. The secondary filtration device 4 can be a cyclone filtration device. The secondary filtration device 4 is a sludge recovery mechanism. The coolant pump 3a is both a sludge recovery pump and a coolant circulation mechanism.

[0029] A resupply unit 5 is connected to the secondary filtration device 4. The resupply unit 5 returns the coolant C, which has been regenerated after sludge has been separated in the secondary filtration device 4, back to the flow path 11. The resupply unit 5 is a pipe that serves as the discharge port from the secondary filtration device 4. The resupply unit 5 is located near the upstream end 11U. It is preferable that the resupply unit 5 discharges the coolant C in a direction away from the partition wall 11c. The resupply unit 5 is a coolant circulation mechanism.

[0030] A pump 8 is positioned at a location along the flow path 11, separated from both the downstream end 11D and the upstream end 11U, that is, in the upper straight section 12b. The pump 8 draws out the purified coolant C in the upper straight section 12b and sends it to the machine tool MC for reuse in cutting and other applications. Multiple pumps 8 can be installed depending on the application.

[0031] The water flow generating unit 2 has ejection holes 2a for discharging coolant C into the flow path 11. Multiple ejection holes 2a are provided within the flow path 11. Coolant C is ejected from the ejection holes 2a along the circumferential direction of the flow path 11. The ejection holes 2a open into the side wall 11a and / or the bottom wall 11b. The ejection holes 2a open inclined toward the flow direction within the flow path 11. As the water flow generation unit 2, a pump 8 can be connected to the discharge port 2a and configured to discharge coolant C into the flow path 11. The water flow generation unit 2 can also be configured to utilize the coolant C ejected from the resupply unit 5 into the flow path 11.

[0032] Figure 3 is a schematic top view showing the coolant flow in the coolant processing apparatus of this embodiment. In the coolant processing apparatus 10 of this embodiment, the water flow generating unit 2 generates a flow (liquid flow) F of coolant C in the flow path 11 of the tank 1. Here, since the flow path 11 is divided by a partition wall 11c, the flow F is formed from the upstream end 11U to the downstream end 11D. On both sides of the partition wall 11c, the coolant C does not move within the flow path 11. At the downstream end 11D, the coolant C is drawn out from the outlet 3 by the coolant pump 3a. The coolant C drawn out from the outlet 3 is returned to the upstream end 11U via the secondary filtration device 4 and the resupply unit 5.

[0033] Thus, within tank 1, the entire volume of coolant C is recirculated via the flow path 11 and the secondary filtration device 4. As shown in Figure 3, this recirculating coolant C flow F circulates clockwise in the following order: resupply section 5, upstream end 11U of the lower straight section 12d, left straight section 12a, upper straight section 12b, right straight section 12c, downstream end 11D of the lower straight section 12d, and outlet section 3. Furthermore, as flow F4, the entire volume of coolant C moves across the partition wall 11c via the secondary filtration device 4.

[0034] In this state, coolant C containing sludge is supplied from the supply section 7 to the lower straight section 12d. In the lower straight section 12d, a unidirectional flow F is formed clockwise throughout the entire tank 1, so the coolant C containing sludge does not flow back into the right-hand straight section 12c. Coolant C containing sludge is drawn in from the outlet 3 by the coolant pump 3a and sent to the secondary filtration device 4. In the secondary filtration device 4, the sludge is separated by the action of centrifugal force, etc. The separated sludge is collected in a drain cup or the like and collected by an operator, for example, at regular intervals. The coolant C, which has been separated from the sludge and purified, is returned to the flow path 11 from the resupply unit 5. Tank 1 has a clean tank on the upstream end 11U side and a dirty tank on the downstream end 11D side.

[0035] In the coolant processing apparatus 10 of this embodiment, since the flow path 11 in the tank 1 is divided by a partition wall 11c, the coolant C does not recirculate without passing through the outlet 3, the secondary filtration device 4, and the resupply unit 5. For this reason, the entire amount of coolant C recirculating in the tank 1 passes through the secondary filtration device 4.

[0036] Therefore, in the coolant treatment device 10, the entire amount of recirculating coolant C can be reliably treated by the secondary filtration device 4. In other words, the coolant C recirculating in the tank 1 reliably passes through the secondary filtration device 4 while recirculating in the tank 1. As a result, sludge can be reliably removed from the coolant C. The coolant C purified by the secondary filtration device 4 maintains a sufficient level of cleanliness. Therefore, the purified coolant C can be sent to the machine tool MC by the pump 8 or the like and reused for cutting, etc.

[0037] At the same time, since the partition wall 11c, which is the dead end of the flow path 11, has R-shaped walls 11a2 and 11b2 formed at the connection points with the side wall 11a and the bottom wall 11b, the coolant C that reaches the partition wall 11c along the flow F is stirred, generating turbulence. As a result, the sludge at the downstream end 11D is stirred up and floats to the surface instead of settling, making it possible to reliably suck up the entire amount from the extraction section 3.

[0038] Furthermore, in the narrower, lower straight section 12d, the flow rate F is greater than in the left straight section 12a, the upper straight section 12b, and the right straight section 12c. As a result, sludge is less likely to accumulate in the lower straight section 12d. In addition, since the supply section 7 is connected to the lower straight section 12d, coolant C containing sludge is supplied from the supply section 7, increasing the flow rate. As a result, the flow rate F in the lower straight section 12d increases compared to the upstream section of the supply section 7. Consequently, the coolant C is further agitated in the lower straight section 12d, making it even less likely for sludge to accumulate.

[0039] The downstream end 11D is located at the lower straight section 12d. In addition, the outlet section 3 is located near the downstream end 11D. In a tank 1 with this configuration, the coolant C can be agitated to a sufficient extent near the outlet section 3 for sludge recovery. Therefore, no sludge remains in the tank 1, and the entire amount can be sucked out from the outlet section 3. As a result, there is no sludge accumulation in the flow path 11, and the secondary filtration device 4 can reliably separate and remove the sludge from the coolant C. This allows for efficient sludge recovery. Furthermore, it reduces the frequency of cleaning tank 1, improving maintenance efficiency.

[0040] Furthermore, since sludge can be reliably removed from the coolant C, clogging of piping and nozzles in the coolant treatment device 10, and a decrease in the performance of the coolant pumps 3a and 8 can be prevented. The lifespan of the coolant C can be extended, allowing for the continued use of clean coolant C, and improving work efficiency by reducing the number of disposal tasks. In addition, the load on the coolant pumps 3a and 8 for recirculating the coolant can be reduced, or the pumps themselves can be made smaller. Therefore, the amount of coolant waste can be reduced, and the environmental burden on the coolant treatment device 10 can be reduced.

[0041] Furthermore, the present inventors conducted experiments on the sludge removal rate using the coolant treatment apparatus of the above embodiment and obtained the result that more than 99% of the sludge could be removed from the coolant C. In other words, the coolant treatment apparatus 10 of this embodiment can achieve a high sludge recovery rate that was not possible with conventional methods.

[0042] This embodiment is not limited to the configuration described above. For example, the configuration can be modified as described below, without departing from the spirit of the present invention. In the illustration of modified examples, the same reference numerals are used for the same components as in the above-described embodiment, and the main differences will be described below. Figure 4 is a schematic plan view (top view) of a modified coolant treatment apparatus of the embodiment described above.

[0043] In this modified version, the flow path width and the water flow generation section 2 are different. In the modified coolant treatment apparatus 10, as shown in Figure 4, the flow path width in the lower straight section 12d is smaller than that in the left straight section 12a and the upper straight section 12b. The flow path width in the right straight section 12c is smaller than that in the lower straight section 12d. In other words, along the flow direction F, the flow path width is first largest in the left straight section 12a and the upper straight section 12b, before reaching the upstream end 11U. Next, the flow path width is smallest in the right straight section 12c, compared to the upper straight section 12b. Furthermore, the flow path width is larger in the lower straight section 12d than in the right straight section 12c.

[0044] In other words, the flow path 11 has a large flow width in the left straight section 12a and the upper straight section 12b, which are near the upstream end 11U, then the smallest flow width in the right straight section 12c, and in the lower straight section 12d the flow width increases in accordance with the increase in the flow rate of the coolant C containing sludge flowing in from the supply section 7, while the downstream end 11D maintains a flow size F that can take in all the sludge.

[0045] The water flow generating unit 2 has multiple ejection holes 2a. The ejection holes 2a are located near the corner 13 between the left straight section 12a and the upper straight section 12b, at the point where the water flows from the upper straight section 12b to the right straight section 12c, and at the connection point between the right straight section 12c and the lower straight section 12d. They may also be located at the upstream end 11U and upstream of the upper straight section 12b. Each ejection hole 2a opens into the bottom wall 11b. The ejection holes 2a open at an angle toward the flow direction within the flow path 11. Coolant C is ejected from each ejection hole 2a along the circumferential direction of the flow path 11.

[0046] The water flow generating unit 2 has a pump 2b. The pump 2b is located near the upstream end 11U and is connected to the discharge port 2a. The pump 2b is located downstream of the resupply unit 5. Similar to the pump 8 and coolant pump 3a described above, the pump 2b pressurizes the coolant C in the tank 1 to the discharge port 2a, forming a flow F in the flow path 11.

[0047] In this configuration, a flow F is formed in each straight section 12 by the coolant C ejected from the ejection holes 2a. Furthermore, by adjusting the width of each flow path, the velocity of the flow F can be increased in the straight section 12c on the right. In addition, the flow F entering the lower straight section 12d from the right straight section 12c at a high velocity is further supplied with coolant C containing sludge from the supply section 7, increasing the flow rate of coolant C. As a result, the velocity of the flow F increases even further in the lower straight section 12d, which is downstream of the supply section 7. At the same time, the flow F that flows into the lower straight section 12d from the right straight section 12c becomes turbulent. Consequently, sludge is less likely to accumulate near the downstream end 11D in the lower straight section 12d.

[0048] In the lower straight section 12d, the downstream end 11D is positioned downstream of the supply section 7, and the outlet section 3 is located near the downstream end 11D. As a result, sludge can be reliably sent to the secondary filtration device 4 without accumulating in the flow path 11. Therefore, no sludge remains in the tank 1. This reduces the frequency of cleaning the tank 1 and improves the efficiency of maintenance.

[0049] A second embodiment of the coolant processing apparatus according to the present invention will be described below with reference to the drawings. Figure 5 is a top view showing the coolant processing apparatus in this embodiment. In this embodiment, the only difference from the first embodiment described above is the shape of the flow path 11. Other components corresponding to the first embodiment described above are denoted by the same reference numerals and their descriptions are omitted.

[0050] In this embodiment, the coolant processing apparatus 10 does not have a rectangular flow path 11 when viewed from above. As shown in Figure 5, the tank 1 of the coolant processing apparatus 10 has a flow path 11 with a roughly U-shape formed by connecting two parallel straight sections 12 at one end. The flow path 11 has a lower straight section 12f and an upper straight section 12g. The lower straight section 12f and the upper straight section 12g are connected at the right end of the figure.

[0051] The left end of the upper straight section 12g is the downstream end 11D. The downstream end 11D is connected such that the side wall 11a and bottom wall 11b are blocked by the partition wall 11c, thereby closing the flow path 11. A supply unit 7 is connected to the upper straight section 12g near its center in the left-right direction. A primary filtration device 6 is positioned above the upper straight section 12g, that is, on the opposite side from the lower straight section 12f. The supply unit 7 in the upper straight section 12g is spaced away from the connection point with the lower straight section 12f to the extent that it does not cause backflow into the right end of the upper straight section 12g, that is, the lower straight section 12f. Similar to the first embodiment, rounded-surface walls 11a2 and 11b2 are formed on the partition wall 11c at the downstream end 11D. Similarly, a rounded-surface wall 11a1 is formed on the corner portion 13 of the upper straight section 12g.

[0052] The left end of the lower straight section 12f is the upstream end 11U. The upstream end 11U is connected such that the side wall 11a and bottom wall 11b are blocked by the partition wall 11c1, thereby closing off the flow path 11. The partition wall 11c and the partition wall 11c1 are formed flush with each other. The lower straight section 12f has a larger flow path width than the upper straight section 12g. The lower straight section 12f has approximately twice the flow path width of the upper straight section 12g. In other words, the flow path width at the upstream end 11U is larger than the flow path width at the downstream end 11D.

[0053] In the lower straight section 12f, multiple pumps 8 are arranged near the upstream end 11U. Unlike the first embodiment, multiple pumps 8 are arranged in the direction of the flow path width. Near the upstream end 11U, a resupply unit 5 is located near the center of the flow path width of the lower straight section 12f. The resupply unit 5 is close to the pumps 8. An R-shaped wall 11a1 is formed at the corner portion 13 of the partition wall 11c1 at the upstream end 11U. Similarly, an R-shaped wall 11a1 is formed at the corner portion 13 of the lower straight section 12f.

[0054] The lower straight section 12f and the upper straight section 12g form a flow path 11, creating a roughly U-shaped flow F with an opening on the left side. Here, because the flow path width of the lower straight section 12f is approximately twice that of the upper straight section 12g, the flow F changes so that its velocity becomes extremely large when it enters the upper straight section 12g from the lower straight section 12f. In addition, since the direction of the flow F reverses by 180° when it enters the upper straight section 12g from the lower straight section 12f, turbulence can also be generated in this state. Moreover, since coolant C containing sludge is supplied from the supply section 7 after it enters the upper straight section 12g from the lower straight section 12f, the coolant C containing sludge does not flow back into the lower straight section 12f, and the accumulation of sludge on the bottom wall 11b in the upper straight section 12g can be suppressed.

[0055] The coolant treatment apparatus 10 of this embodiment has a U-shaped flow path 11 with an adjacent upstream end 11U and downstream end 11D, which allows for a smaller installation area than the first embodiment. Therefore, the apparatus can be made smaller and more space-saving. Since the flow path width at the upstream end 11U is about twice as large as the flow path width at the downstream end 11D, it becomes easier to increase the velocity change of the flow F and suppress sludge accumulation.

[0056] Alternatively, although this embodiment uses a configuration with a substantially U-shaped flow path 11, it is also possible to use a configuration with a substantially S-shaped flow path 11 formed by connecting three parallel straight sections 12, or a flow path 11 formed by connecting four parallel straight sections 12.

[0057] In this embodiment, the same effects as those of the above-described embodiment can be achieved.

[0058] Furthermore, in the present invention, it is also possible to individually select and combine each of the configurations in the above-described embodiments. [Explanation of Symbols]

[0059] 1... Tank 2...Water flow generation section 2a...Blowout hole 2b... Pump 3...Ejecting part 3a... Coolant pump 4…Secondary filtration system 5...Resupply section 6…Primary filtration system 7...Supply section 8... Pump 10... Coolant treatment device 11…flow channel 11a…Side wall 11a1,11a2…Inner R side wall (R side wall) 11b…Bottom wall (bottom) 11b2…R side wall 11c, 11c1... partition wall 11D…Downstream end 11U...Upstream end 12,12a,12b,12c,12d,12f,12g...Straight section 13...Corner section C... Coolant MC…Machine tool

Claims

1. A flow path provided in a tank where coolant is stored, A secondary filtration device that extracts and filters the coolant from the aforementioned flow path, An extraction unit that extracts coolant from the downstream end of the aforementioned flow path and sends it to the secondary filtration device, A resupply unit that returns the coolant filtered from the secondary filtration device to the upstream end of the flow path, Equipped with, The coolant is recirculated through the aforementioned flow path and the aforementioned secondary filtration device. Coolant treatment device.

2. The downstream end of the aforementioned channel is narrower than the upstream end. The coolant processing apparatus according to claim 1.

3. The downstream end of the aforementioned flow path has a curved R-shaped wall at the connection point with the side wall. The coolant processing apparatus according to claim 1.

4. The downstream end of the aforementioned channel has a curved R-shaped wall surface at the connection point with the bottom wall. The coolant processing apparatus according to claim 1.

5. The extraction section has a width approximately equal to that of the downstream end of the flow path. The coolant processing apparatus according to claim 1.

6. A supply unit for supplying coolant from the primary filter is connected to a position upstream of the downstream end of the aforementioned flow path. The coolant processing apparatus according to claim 1.

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