Coolant tank and circulation device including the same

Abstract

To provide a coolant tank which can prevent overflowing of a coolant liquid from a dirty tank to increase an amount of the stored coolant liquid.SOLUTION: A coolant tank 1 includes: a dirty tank 2 in which a coolant liquid before filtration is stored; and a clean tank 3 in which the coolant liquid after the filtration is stored. The clean tank 3 includes: a first clean tank 31 into which the coolant liquid after the filtration flows; a second clean tank 32 into which the coolant liquid flows from the first clean tank 31; and a passage 33a for allowing the coolant liquid to flow from the first clean tank 31 to the second clean tank 32. The first clean tank 31 is formed so that its height is higher than a height of the second clean tank 32. The dirty tank 2 and the second clean tank 32 are disposed adjacent to each other while sandwiching a partition wall therebetween. A communication part 4 which allows the dirty tank 2 and the second clean tank 32 to communicate with each other is provided at an upper end or an area near the upper end of the partition wall.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a coolant tank for storing coolant used in machine tools and the like, and in particular to a coolant tank for storing both unfiltered and filtered coolant, and a circulation device equipped with a coolant tank. [Background technology]

[0002] Conventionally, coolant fluids, such as cutting oil and grinding oil, have been used in machine tools. Since coolant fluids are used not only for cooling and lubrication but also for cleaning purposes, solid particulate matter such as cutting chips and grinding chips (hereinafter referred to as sludge) is mixed into the used coolant fluid. Generally, this coolant fluid is repeatedly used through a circulation device, but since using coolant fluid containing sludge affects machining such as cutting, it is necessary to remove the sludge from the coolant fluid once it has been used. In such circulation devices, a coolant tank is generally used to store the coolant fluid before and after filtration.

[0003] FIG. 6 is a diagram showing a schematic diagram of a system including a machine tool 100 and a circulation device 200. As shown in the figure, the circulation device 200 is provided with a coolant tank 210, which includes a dirty tank 211 and a clean tank 212. Coolant liquid that has been used and has sludge mixed in flows into the dirty tank 211 through a flow path 201. The coolant liquid that flows into the dirty tank 211 is supplied to a filtration device 204 through a flow path 203 by a pump 202. In the filtration device 204, sludge is filtered from the coolant liquid, and the coolant liquid from which the sludge has been removed flows into a clean tank 212 through a flow path 205. The coolant liquid that flows into the clean tank 212 is supplied again to the machine tool 100 through a flow path 207 by a pump 206.

[0004] In such a circulation device 200, if the amount of coolant discharged to the filtration device 204 decreases due to, for example, a malfunction or deterioration in performance of the pump 202 or clogging of the flow path 203, the coolant may overflow from the dirty tank 211.

[0005] In order to prevent such overflow of coolant from a dirty tank, for example, Patent Document 1 discloses a coolant tank in which a primary tank (dirty tank) and a secondary tank (clean tank) are arranged adjacent to each other and a communication part is provided in the gas phase area above them. In the device of Patent Document 1, when the amount of coolant in the primary tank increases, the coolant in the primary tank flows out into the secondary tank through this communication part, thereby preventing overflow of the coolant from the primary tank.

[0006] Also, there is a demand for the coolant tank to have an increased amount of coolant liquid stored therein from the viewpoint of cooling performance, sludge removal capacity, etc. In order to increase the amount of coolant liquid stored therein, it is sufficient to increase the volume of the clean tank, and methods for this include increasing the installation area or height of the clean tank, or both. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] International Publication WO2019 / 058719 Brochure Summary of the Invention [Problem to be solved by the invention]

[0008] Increasing the installation area to increase the amount of coolant stored is not preferable from the viewpoint of efficient use in the factory where the machine tool and the coolant tank are installed. On the other hand, increasing the height of the coolant tank can also cause problems. Generally, the supply of coolant from the machine tool to the coolant tank is performed by a difference in height, so if the height of the coolant tank is increased, it is necessary to set the machine tool at a higher position or bury the coolant tank, thereby creating a difference in height between the machine tool and the coolant tank, which makes the installation difficult.

[0009] In order to increase the amount of coolant stored while maintaining the height difference between the machine tool and the coolant tank (especially the dirty tank), it is possible to increase the volume of the clean tank. However, since it is not desirable to increase the installation area of ​​the clean tank, it is preferable to increase the height of the clean tank.

[0010] If this is applied to the coolant tank of Patent Document 1, it is possible to solve both problems of preventing the coolant liquid from overflowing from the dirty tank and increasing the amount of stored coolant liquid. However, in the coolant tank of Patent Document 1, it is necessary to provide a communication part in the gas phase region between the dirty tank and the clean tank, so the height of the dirty tank and the height of the clean tank must be approximately the same. In other words, in the coolant tank of Patent Document 1, it is not possible to change only the height of the clean tank.

[0011] In other words, conventional technology was unable to solve the two problems of preventing the coolant from overflowing from the dirty tank and increasing the amount of coolant that could be stored.

[0012] The present invention has been made in consideration of the above-mentioned problems, and its object is to provide a coolant tank that has a simple configuration yet prevents coolant liquid from overflowing from a dirty tank and can increase the amount of coolant liquid stored without increasing the installation area, and a circulation device equipped with a coolant tank. [Means for solving the problem]

[0013] In order to solve the above problems, the present invention provides a coolant tank comprising a dirty tank for storing pre-filtered coolant, which is coolant before it is filtered, and a clean tank for storing filtered coolant obtained by filtering the pre-filtered coolant, the clean tank comprising a first clean tank into which the filtered coolant flows, a second clean tank into which the filtered coolant flows from the first clean tank, and a flow path for flowing the filtered coolant from the first clean tank to the second clean tank, the height of the first clean tank being greater than the height of the second clean tank, the dirty tank and the second clean tank being disposed adjacent to each other with a partition therebetween, and a communication portion communicating between the dirty tank and the second clean tank being provided at or near the upper end of the partition.

[0014] In this configuration, the clean tank is composed of a second clean tank and a first clean tank that is higher than the second clean tank. This allows the volume of the coolant tank, especially the clean tank, to be increased without increasing the installation area. In addition, since a communication part is formed in the partition between the dirty tank and the second clean tank, if the coolant in the dirty tank increases due to a malfunction or the like, the coolant flows out through the communication part into the second clean tank. This makes it possible to prevent the coolant from overflowing from the dirty tank.

[0015] Filtered coolant flows into the first clean tank, but there is a possibility that some sludge remains in the coolant after filtration. Since the specific gravity of this sludge is greater than that of the coolant, it is thought to settle or float near the bottom in the first clean tank. In other words, it is thought that there is less sludge in the upper part of the coolant in the first clean tank than in the lower part.

[0016] In view of this point, in one preferred embodiment of the coolant tank according to the present invention, the first clean tank and the second clean tank are provided separately from each other, and an outlet portion for causing the filtered coolant liquid to flow toward the flow path is formed near the upper end of the first clean tank.

[0017] In this configuration, the coolant liquid at the top of the first clean tank, i.e., the coolant liquid with less sludge and cleaner, can flow into the second clean tank.

[0018] The present invention also covers a circulation device comprising the above-mentioned coolant tank and a filtration device that filters the coolant liquid, and such a circulation device comprises a first pump for flowing the unfiltered coolant liquid from the dirty tank to the filtration device, and a second pump for discharging the filtered coolant liquid from the second clean tank, and the discharge volume of the first pump is greater than the discharge volume of the second pump.

[0019] In the coolant tank according to the present invention, the dirty tank and the second clean tank are connected through a communication part, so that the unfiltered coolant liquid containing a large amount of sludge in the dirty tank may flow into the second clean tank. However, in this configuration, the coolant liquid in the second coolant tank normally always flows into the dirty tank, so that the unfiltered coolant liquid can be prevented from mixing with the filtered coolant liquid in the second clean tank. [Brief description of the drawings]

[0020] [Figure 1] 1 is a simplified diagram of a machine tool and a circulation device including a coolant tank according to the present invention; [Diagram 2] FIG. 2 is a schematic perspective view of a coolant tank. [Diagram 3] FIG. 3 is a cross-sectional perspective view taken along line III-III in FIG. [Figure 4] FIG. 6 is a cross-sectional perspective view taken along the line VI-VI in FIG. [Diagram 5]FIG. 3 is a cross-sectional perspective view of FIG. 2; [Figure 6] 1 is a simplified diagram of a machine tool and a circulation device with a prior art coolant tank; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] The embodiment of the coolant tank according to the present invention will be described below with reference to the drawings. Fig. 1 is a simplified diagram of a machine tool A that performs cutting, grinding, etc., and a circulation device B that circulates a coolant liquid for cleaning, cooling, and lubricating the machine tool A.

[0022] The circulation device B includes flow paths a1, a2, c1, and c2 for flowing the coolant, a coolant tank 1 according to the present invention for storing the coolant, a filtration device C for filtering sludge from the coolant, and a first pump P1 and a second pump P2 for circulating the coolant. As the filtration device C, for example, a filter device disclosed in JP 2023-025359 A can be used.

[0023] As described below, the coolant tank 1 includes a dirty tank 2 for storing coolant liquid containing sludge (unfiltered coolant liquid), and a clean tank 3 for storing coolant liquid from which the sludge has been filtered by a filtration device C (filtered coolant liquid).

[0024] The flow path a1 is for supplying used coolant (unfiltered coolant) from the machine tool A to the dirty tank 2. The flow path c1 is for supplying unfiltered coolant from the dirty tank 2 to the filtration device C by the action of the first pump P1. The flow path c2 is for supplying coolant from which sludge has been filtered by the filtration device C (filtered coolant) from the filtration device C to the clean tank 3. The flow path a2 is for supplying coolant from the clean tank 3 again to the machine tool A by the action of the second pump P2.

[0025] 2 is a schematic perspective view of the coolant tank 1 in this embodiment. As shown in the figure, the coolant tank 1 includes a dirty tank 2 that stores pre-filtered coolant liquid containing sludge, and a clean tank 3 that stores filtered coolant liquid. The clean tank 3 includes a first clean tank 31 and a second clean tank 32. In this embodiment, the dirty tank 2, the first clean tank 31, and the second clean tank 32 are each formed in a hollow rectangular parallelepiped shape, and the first clean tank and the second clean tank 32 are arranged so as to be adjacent to each other. In addition, both the first clean tank 31 and the second clean tank 32 are arranged so as to be adjacent to the dirty tank 2.

[0026] A pipe ap1 is connected to the top surface of the dirty tank 2. Unfiltered coolant from the machine tool A flows into the dirty tank 2 through a flow path a1 in this pipe ap1. One end of a pipe cp1 penetrates the top surface of the dirty tank 2, and the other end of the pipe cp1 is connected to a filtering device C. Unfiltered coolant in the dirty tank 2 is supplied to the filtering device C through a flow path c1 in this pipe cp1.

[0027] On the other hand, a pipe cp2 extends from the filtering device C to the first clean tank 31. The filtered coolant liquid from which sludge has been filtered by the filtering device C flows into the first clean tank 31 through a flow path c2 in the pipe cp2.

[0028] An L-shaped pipe 33 is provided from the side wall of the first clean tank 31 to the upper surface of the second clean tank 32. The L-shaped pipe 33 is hollow and has a flow path 33a (an example of a flow path in the present invention) formed therein. The coolant liquid in the first clean tank 31 flows into the second clean tank 32 through this flow path 33a.

[0029] A pipe ap2 is provided penetrating the upper surface of the second clean tank 32. The coolant liquid in the second clean tank 32 is supplied to the machine tool A through a flow path a2 in this pipe ap2, and is used again for cleaning, cooling, lubrication, and the like.

[0030] The circulation device B is equipped with a magnet separator for removing magnetic material, a cooling device for cooling the coolant liquid, and the like, but these are not shown or described.

[0031] The coolant tank 1 according to the present invention in this embodiment will be described in detail below with reference to Figures 2 to 5. Figures 3 to 5 are a cross-sectional perspective view taken along lines III-III, IV-IV, and VV in Figure 2, respectively, but the first pump P1 and the second pump P2 are omitted from the illustration.

[0032] The coolant tank 1 is arranged so as to be rectangular in plan view, with half of the width being the dirty tank 2 and the remaining half being the clean tank 3. However, as shown in FIG. 2, their heights are different. Specifically, the dirty tank 2 and the second clean tank 32 are the same height, but the first clean tank 31 is higher than them. In this way, by partially raising the height of the clean tank 3, it is possible to increase the capacity of the coolant tank 1, particularly the clean tank 3, and to increase the amount of coolant liquid stored.

[0033] 3, an opening 31a (corresponding to the outflow portion in the present invention) is formed by cutting out a rectangular shape from the upper end of the side wall of the first clean tank 31 on the second clean tank 32 side. The shape of this opening 31a is formed to match the outer shape of the end of the L-shaped pipe 33 on the first clean tank 31 side. Therefore, the coolant liquid overflowing from the first clean tank 31 flows out from the opening 31a and passes through the flow path 33a into the second clean tank 32.

[0034] The first clean tank 31 receives filtered coolant from which sludge has been filtered by the filtration device C, but there is a possibility that some sludge may remain in the filtered coolant. Generally, the specific gravity of sludge is greater than that of the coolant, so the sludge settles or floats near the bottom in the first clean tank 31. Therefore, it is considered that the upper part of the coolant in the first clean tank 31 contains less sludge. Therefore, by allowing the coolant to overflow from near the upper end of the first clean tank 31, cleaner coolant can be supplied to the second clean tank 32 and further to the machine tool A.

[0035] 2 and 4, in the wall surface (corresponding to the partition wall in the present invention) of the dirty tank 2 on the clean tank 3 side, a rectangular opening is formed in the portion facing the second clean tank 32. Meanwhile, in the wall surface (corresponding to the partition wall in the present invention) of the second clean tank 32 on the dirty tank 2 side, a rectangular opening is also formed in the wall surface. These openings have the same shape and are formed at opposing positions, constituting a communication part 4. That is, the dirty tank 2 and the second clean tank 32 are in communication with each other via the communication part 4.

[0036] Next, the flow of coolant under normal conditions (represented by dotted arrows in FIG. 2) will be described. The coolant used in machine tool A flows into dirty tank 2 through pipe ap1. The coolant in dirty tank 2 is supplied to filtration device C through pipe cp1 by first pump P1. In filtration device C, sludge is filtered out of the coolant, and after filtration, the coolant flows into first clean tank 31 through pipe cp2.

[0037] When the liquid level of the coolant in the first clean tank 31 exceeds the lower end of the opening 31a, the coolant overflows from the opening 31a and flows through the flow path 33a into the second clean tank 32. As described above, the sludge remaining in the coolant after filtration settles or floats near the bottom in the first clean tank 31, so the coolant that overflows from the first clean tank 31 contains even less sludge and the like.

[0038] The coolant liquid in the second clean tank 32 is supplied again to the machine tool A through the pipe ap2 by the second pump P2.

[0039] In this embodiment, the discharge rate of the first pump P1 is set to be larger than the discharge rate of the second pump P2. By setting the pump discharge rates in this manner, the flow rate of the coolant liquid into the clean tank 3 becomes larger than the flow rate of the coolant liquid out of the clean tank 3, so that a sufficient amount of coolant liquid can be stored in the clean tank 3 and the coolant liquid can be prevented from running out.

[0040] In the coolant tank 1 according to the present invention, the dirty tank 2 and the second clean tank 32 are connected to each other through the communication part 4, so that the unfiltered coolant liquid in the dirty tank 2 may flow into the second clean tank 32. However, by setting the discharge amount of the pump as described above, this problem can be solved. Specifically, overflow from the second clean tank 32 occurs due to the difference between the amount of coolant liquid flowing into the clean tank 3 and the amount of coolant liquid flowing out from the clean tank 3. The overflowed coolant liquid from the second clean tank 32 flows into the dirty tank 2 through the communication part 4. That is, in this embodiment, a flow from the second clean tank 32 to the dirty tank 2 always occurs under normal circumstances. As a result, even if the dirty tank 2 and the second clean tank 32 are connected to each other through the communication part 4, the unfiltered coolant liquid can be prevented from flowing into the clean tank 3.

[0041] On the other hand, when the discharge rate of the first pump P1 decreases due to a failure of the first pump P1 or the like, the storage amount of the dirty tank 2 increases and the storage amount of the clean tank 3 decreases. At this time, the coolant flows out from the dirty tank 2 toward the second clean tank 32 through the communication part 4. This makes it possible to prevent the coolant from overflowing from the dirty tank 2. However, since there is a limit to the storage amount of the clean tank 3, in such a case, it is necessary to immediately stop the device and stop the circulation of the coolant.

[0042] In this way, in the present invention, by providing the communication part 4 between the dirty tank 2 and the clean tank 3, when the amount of coolant in the dirty tank 2 increases abnormally, the coolant in the dirty tank 2 is released to the clean tank 3 via the communication part 4, thereby preventing the coolant from overflowing from the dirty tank 2. Also, by raising a part of the clean tank 3, the amount of coolant stored in the entire clean tank 3 can be increased. In other words, the coolant tank 1 according to the present invention can prevent the coolant from overflowing from the dirty tank 2 and increase the amount of coolant stored in the clean tank 3 without increasing the installation area.

[0043] [Another embodiment] (1) In the above embodiment, the clean tank 3 is composed of the first clean tank 31 and the second clean tank 32 that are provided separately, but the first clean tank 31 and the second clean tank 32 may be formed integrally. In this case, the external L-shaped pipe 33 (flow path 33a) is not necessary. At this time, a partition wall separating the first clean tank 31 and the second clean tank 32 may or may not be provided inside the clean tank 3. In the former case, a partition wall separating the first clean tank 31 and the second clean tank 32 may be provided in the partition wall, and an opening serving as the flow path 33a may be formed in the partition wall. On the other hand, in the latter case, the entire boundary portion between the first clean tank 31 and the second clean tank 32 serves as the flow path 33a. In the latter case, although the effect of sludge settling in the first clean tank 31 cannot be expected, the original object of the present invention can be achieved.

[0044] (2) In the above-described embodiment, the dirty tank 2, the first clean tank 31, and the second clean tank 32 are each formed as a hollow rectangular parallelepiped member and disposed adjacent to each other. However, these may also be formed integrally with partitions provided to separate them.

[0045] (3) In the above embodiment, the first clean tank 31 and the second clean tank 32 are disposed adjacent to each other, but they may also be disposed spaced apart.

[0046] (4) In the above embodiment, the coolant is caused to overflow from the first clean tank 31 and flow into the second clean tank 32. However, a pump or the like may be used instead.

[0047] (5) In the above embodiment, the flow path a1 is formed using the pipe ap1 to supply the coolant from the machine tool A to the dirty tank 2, but a member of another shape, such as a trough-shaped member, may be used instead of the pipe ap1. Also, the coolant may be dropped from the machine tool A to the opening of the dirty tank 2 without using these members. [Industrial Applicability]

[0048] The present invention can be used in coolant tanks for storing coolant used in machine tools and other coolant that is filtered after use and reused, specifically, in coolant tanks that store coolant before and after filtration. [Explanation of symbols]

[0049] A: Machine tool B: Circulation device C:Filtration device P1: First pump P2: Second pump 1: Coolant tank 2: Dirty Tank 3: Clean tank 31: First clean tank 31a: Opening (outflow part) 32: Second clean tank 33: L-shaped tube 33a: Flow path 4: Communication part

Claims

1. A coolant tank including a dirty tank for storing pre-filtered coolant liquid, which is a coolant liquid before filtering, and a clean tank for storing filtered coolant liquid obtained by filtering the pre-filtered coolant liquid, The clean tank comprises: a first clean tank into which the filtered coolant flows; a second clean tank into which the filtered coolant liquid flows from the first clean tank; a flow path for allowing the filtered coolant liquid to flow from the first clean tank to the second clean tank, The height of the first clean tank is greater than the height of the second clean tank, The dirty tank and the second clean tank are disposed adjacent to each other with a partition wall therebetween, The coolant tank has a communication portion provided at or near the upper end of the partition wall, the communication portion connecting the dirty tank and the second clean tank.

2. The first clean tank and the second clean tank are provided separately from each other, 2. The coolant tank according to claim 1, wherein an outlet portion for causing the filtered coolant to flow toward the flow path is formed in the vicinity of an upper end of the first clean tank.

3. 3. A circulation system comprising the coolant tank according to claim 1 or 2 and a filtration device for filtering the coolant liquid, a first pump for causing the unfiltered coolant liquid to flow from the dirty tank to the filtering device; a second pump for discharging the filtered coolant from the second clean tank, A circulation device in which the discharge volume of the first pump is greater than the discharge volume of the second pump.

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