JPWO2019189212A1 - Coolant quality management system and coolant quality detection unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coolant quality management system for detecting the quality of a coolant for cooling a processing tool while a metal processing apparatus is operating or stopped, and a coolant quality detection unit used therefor. SOLUTION: The present coolant quality management system separates the coolant near the liquid level in the coolant storage tank in the coolant supply flow path at least every predetermined time or period. It is provided with a temperature measuring means, a concentration measuring means and a pH value measuring means for measuring the temperature, concentration and pH value, respectively, and the concentration measuring means adjusts the concentration based on the change in the refractive index of the light of the separated coolant. The concentration is measured by conversion, and the pH value measuring means measures the pH value by estimating the hydrogen ion concentration based on the change in the conductivity of the separated coolant, and the temperature measuring means and the concentration measuring means. The measurement of the separated coolant by the means and the pH value measuring means is performed at the same time. [Selection diagram] Fig. 4

Description

According to the present invention, the cooling liquid in operation in a metal processing apparatus can be periodically measured by various sensors (thermometer, densitometer, pH meter) and centrally managed externally, and physical phenomena that hinder the operation of various sensors can be avoided (). It relates to a coolant quality management system and a coolant quality management system, which are easy to introduce the system, have stable measurement, and can easily obtain a standardized evaluation against changes in processing conditions.

Cooling of processing tools during processing in metal processing equipment greatly affects the processing accuracy, yield, tool life, etc. of products, but the state of cooling oil for each equipment, tools used, and processing process (work). Was not measured, and it was left to the rule of thumb of the workers at the site. In a high-precision processing site, it may be managed by an additional coolant cooling device that cools the cooling oil, but the coolant cooling device is large and expensive and has not been widely spread in the field, and the management is also done by the cooling oil manufacturer. Only control under specified standard thresholds and usage conditions (concentration, pH, replacement frequency, recommended replacement time, etc.) is not the optimum that contributes to the accuracy of machined parts and tool life at individual sites. It was.

Therefore, for each processing condition, the quality of each processing device (cutting device, grinding device, lathe device, forging device, casting device, etc., widely used in metal processing equipment) is quantified when actual processing is performed using coolants of various specifications. There was an increasing social and potential need for a system that could be evaluated in a positive manner. Applicants who have proposed measurement and evaluation techniques during machining of each machining tool (see Patent Documents 1 and 2) are closely related to these techniques and can be combined and developed as a coolant for machining tools in metal processing equipment (see Patent Documents 1 and 2). Provided is a coolant quality detection system that measures temperature, concentration, amount of impurities, etc. in a flow path for supplying (hereinafter, also referred to as “coolant”) and wirelessly transmits the coolant to the outside (Patent Document 3 (International Application PCT /). JP2017 / 035050)).

In the coolant quality detection system proposed by the applicant, the temperature, concentration, and pH value of the coolant can be periodically measured at predetermined time or period during the operation of the metal processing apparatus, and the change in the measured values can be used. It is possible to objectively detect the performance deterioration of the coolant as numerical data and quantitatively determine the performance deterioration of the coolant. As a result, evaluation and management are performed in real time to avoid tool fatigue and breakage caused by changes and deterioration of the coolant over time, as well as to avoid a decrease in machining accuracy of the workpiece and a decrease in product yield. be able to.

However, in the above-mentioned coolant quality detection system, various installation locations of various sensors (thermometer, concentration meter, pH meter) have been proposed selectively, but after that, the applicant continued the practical development and development of the sensor. Issues and good configurations have been found to ensure long-term measurable durability while avoiding operational failures. In addition, the ease of specific installation and measurement at each position where various sensors are installed in the actual processing equipment was also examined. Further, when evaluating the quality of the coolant during actual processing, it is preferable that the relationship between the measurement data and the quality of the coolant can be standardized and quantitatively evaluated regardless of the processing conditions of metal processing. ) Is also required to provide a good concrete configuration.

International Publication WO2015-022967 International Publication WO2016-11136 International application PCT / JP2017 / 035050

The present invention has been created in view of the above circumstances, and is a physical phenomenon that interferes with the operation of various sensors (thermometer, densitometer, pH meter) in a coolant quality detection system for a coolant in a metal processing apparatus. The purpose is to provide a concrete coolant quality detection system configuration that makes it easy to introduce the system, stabilize the measurement, and easily obtain a standardized evaluation for changes in processing conditions, while avoiding (or reducing) the above. To do.

The present invention is a coolant quality management system that detects the quality of a coolant that cools a processing tool during the operation of a metal processing apparatus, and at least
The coolant in the intermediate layer from the bottom to the liquid surface in the coolant storage tank in the coolant supply flow path in the coolant supply flow path is separated at predetermined time or period, and the temperature, concentration and pH value thereof are set respectively. It is equipped with a temperature measuring means, a concentration measuring means, and / or a pH value measuring means for measuring.
The concentration measuring means measures the concentration by converting the concentration into a concentration based on the change in the refractive index of the light of the separated coolant, and the pH value measuring means changes the conductivity of the separated coolant. Measure the pH value by estimating the hydrogen ion concentration based on
The temperature measuring means, the concentration measuring means, and / or the pH value measuring means measure the separated coolant at the same time.

In the coolant quality detection system for coolants in metal processing equipment, Patent Document 3 uses the temperature change of the coolant as the main evaluation index for the quality of the coolant, but the temperature change is the configuration of the equipment, processing conditions, environmental conditions, and measurement location. Various changes have been made for each, and it has become clear that it is difficult to standardize only this as an index for coolant evaluation. Therefore, it has been found that it is preferable to measure the concentration and pH value as a direct quality index of the coolant in addition to the temperature change as an essential measurement index.

On the other hand, as physical phenomena that cause obstacles to the operation of various sensors (temperature measuring means, concentration measuring means, pH value measuring means), air bubbles are mixed in the coolant, cutting chips are mixed, and the liquid due to the increase or decrease of the coolant is used. Surface fluctuations and temperature changes are typical. In the concentration measuring means (concentration meter) that converts the concentration by using the change in the refractive index of light, the type of coolant is different when air bubbles or cutting chips (metal pieces) are mixed in the coolant. In the same way as above, the conversion coefficient presented by the coolant manufacturer may be affected, and the reliability of the measurement data (measured concentration) decreases.

In addition, the pH value measuring means (pH meter) that estimates the hydrogen ion concentration using the change in conductivity (electric resistance) basically measures only the aqueous coolant as long as the change in conductivity is measured. Appropriate measurement data (measured pH value) will be output if air bubbles are mixed in the coolant, water-insoluble floating oil is generated, cutting chips (metal pieces) are mixed, or the liquid level fluctuates because it cannot be targeted. It will be difficult. On the other hand, it is conceivable to install a filter in the piping flow path of the circulation system or remove the cutting waste, air bubbles and floating oil by replacing the piping, but it is difficult to remove the water-insoluble floating oil only by the filter, and it is a long-term. Considering continuous use, measures against clogging and maintenance of pipe replacement are complicated, and backwashing may cause damage to the instrument because accumulated cutting debris will fly away. Therefore, in the present invention, the cooling liquid is temporarily stored as still water as a place where air bubbles, water-insoluble floating oil, and cutting chips are prevented from being mixed in the cooling flow path and measurement can be performed at a place where the liquid level fluctuation is small. We paid attention to the coolant in the tank. In the storage tank, the liquid level fluctuation is small due to temporary storage, and cutting chips settle to the bottom and aerate the air bubbles. Therefore, especially the coolant at the height of the intermediate layer from the liquid level to the bottom in the "storage tank" (hereinafter , Also referred to as "intermediate layer coolant") was found to be preferable to "precipitate" or selectively measure.

Further, both the concentration measuring means and the pH value measuring means have a large temperature dependence of the measured data, and a large temperature change is expected depending on the quality of the coolant (originally, the relationship between the temperature change and the quality of the coolant). The original developed technique of the present invention (Patent Document 3) was created), concentration measurement and pH value measurement under the same temperature state are preferable, and in the present invention, temperature, concentration and / or pH value measurement are performed at the same time. I decided to do it.

Further, the temperature measuring means may be composed of a separate thermometer and / or a built-in thermometer of the concentration measuring means and the pH value measuring means.

As described above, the measurement data of the concentration and the pH value are highly temperature-dependent, and it is desirable to evaluate the measurement data under the same temperature conditions. On the other hand, the concentration measuring means and the pH value measuring means may be provided with a built-in thermometer that automatically corrects for temperature changes in order to eliminate temperature dependence. Therefore, as a correction for removing the temperature dependence of the concentration measurement data and the pH value measurement data, (1) the temperature measurement data from the thermometer for temperature change measurement (separate thermometer) as an evaluation index of the quality of the coolant is used. It may be used, or (2) the automatic correction function for temperature changes by a built-in thermometer such as a densitometer may be used.

The storage tank is composed of a plurality of containers having different liquid levels and opened upward.
When the coolant near the liquid level in the storage tank is separated, the coolant discharged to the outside from the outlet of the container on the upstream upper side may be poured into the container on the downstream lower side.

In this coolant quality management system, in order to separate only the coolant that is good for measurement other than drainage, including floating oil in the storage tank and metal waste accumulated at the bottom, multiple containers are installed in multiple stages in the vertical direction. It is conceivable to pour the coolant of the intermediate layer in the container on the upstream side to the downstream side. In this example, impurities such as cutting chips and water-insoluble floating oil are removed in order by simply separating the coolant in the intermediate layer several times. Especially when there is a lot of cutting waste or a lot of rotten sediment. It is effective when water-insoluble floating oil is accumulated near the liquid surface. Specific examples will be described later.

Further, it is preferable that the concentration measuring means and the pH value measuring means are measured in a state where the flow of the cooling liquid and the liquid level do not fluctuate and / or in a state where the flow of the cooling liquid is stopped.

Specifically, it is preferable to intermittently operate the suction pump that sucks the coolant in the coolant quality detection unit described later.

Further, the present invention is arranged in a bypass flow path separated from the coolant in the storage tank in the above-mentioned present coolant quality management system, and the concentration and pH value of the coolant in the bypass flow path are set, respectively. Concentration measuring means and pH value measuring means to measure,
A storage tank for storing the coolant in the bypass flow path and
Provided is a coolant quality detection unit including a suction pump for sucking the coolant in the storage tank.

This coolant quality detection unit is a unit that is installed in the bypass flow path process separated from the storage tank in the above-mentioned coolant quality management system to measure the concentration and pH value. This unit also has a storage tank in it, and since the coolant is temporarily stored in this storage tank, it has the function of a settling tank in which cutting chips settle on the bottom like the storage tank of the metal processing equipment described above. It has the function of an aeration tank that removes air bubbles. In addition, this coolant quality detection unit is provided with a suction pump for separating the coolant from the storage tank to facilitate the supply of coolant into the unit (especially the supply to the densitometer and pH meter), and the suction pump. By measuring the concentration and pH value at the time of operation, even a small unit can perform proper measurement.

In addition, this coolant quality detection unit is
A replaceable filter that filters the coolant in the bypass flow path and
It is preferable to include a flow rate sensor for measuring the flow rate of the coolant in the bypass flow path.

The storage tank is preferably provided with a filter for filtering the coolant, and the filter removes cutting chips. It is also possible to detect clogging, which detects that the filter is clogged when the flow rate of the coolant is reduced by the flow rate sensor.

Further, the storage tank is arranged in a raised floor in the coolant quality detection unit, and the coolant in the bypass flow path flows in from the upper inflow port of the storage tank and is discharged from the lower outflow port. It is preferable to be done.

By adopting this configuration, it is possible to remove cutting chips when passing through the storage tank and adjust the balance between the smooth flow of the coolant from upstream to downstream, and the unit design according to the output of the suction pump. It will be possible.

Further, the concentration measuring means of the coolant quality detection unit is provided with a storage unit for measurement for storing the coolant and measuring the refractive index of light.
The measurement storage unit has an inflow port for the coolant to flow in and an outflow port for the coolant to flow out, and each of the inflow port and the outflow port measures the concentration of the coolant in the measurement storage unit. It is provided with a normal inflow port and a normal inflow port for cleaning, a cleaning inflow port and a cleaning inflow port for cleaning the inside of the measurement storage part, and the cleaning inflow port and the cleaning outflow port are respectively from the end. It is preferable that the flow path leading to the measurement storage portion is a substantially straight line, and the normal inflow port and the normal use outlet are each provided with a curved portion in the flow path from the end portion to the measurement storage portion.

According to the concentration measuring means of this coolant quality detection unit, the outflow port for normal operation (during measurement) and the outflow port for cleaning are shared, so it is the same as the normal operation just by replacing the end part for cleaning. The measurement reservoir can be cleaned with the discharged coolant, cutting chips and the like in the measurement reservoir can be easily and surely cleaned, and the concentration can always be measured with high measurement accuracy. In addition, since the outflow port for cleaning is provided with a linear coolant approach section, there is no decrease in flow velocity, and the coolant jet flow with an approximate trajectory can be radiated in the storage unit for measurement, so the cleaning power can be maintained high. At the same time, it is also possible to provide a bending portion (bending portion or the like) at the outflow port for normal use to reduce the flow velocity of the coolant and remove air bubbles.

Further, it is preferable that the pH value measuring means is mounted on the storage tank to measure the cooling liquid inside the storage tank, and the storage tank is made of an electrically insulating material.

In measuring the pH value, the storage tank 21 to which the pH meter 9 is attached is made of an electrically insulating material, or the coolant liquid inside the storage tank 21 is electrically floated (non-electrically conductive) to make cutting oil. Due to the circulation of, the cutting oil electrically connected to the external device and the cutting oil to be measured for the pH value form a circuit, and the potential in the tank does not fluctuate, making measurement with a pH meter impossible or error. The occurrence of the phenomenon that becomes large is suppressed.

Further, in the coolant quality management system, a concentration measuring means which is arranged in a bypass flow path separated from the coolant in the storage tank and measures the concentration of the coolant in the bypass flow path, and a concentration measuring means.
A suction pump for sucking the coolant in the storage tank is provided.
The concentration measuring means measures the refractive index of the light of the coolant with a lens disposed inside by allowing the coolant to flow in and out of the measuring reservoir arranged in the bypass flow path, and the measurement is performed. The storage unit may be a coolant quality detection unit in which the outlet of the coolant is located at the uppermost portion and the lens is tilted and positioned so as to be arranged on the tilted portion.

According to this concentration measuring means, the outlet is stored for measurement so that the water-insoluble floating oil is extracted and the lens is not immersed in the water-insoluble coolant and measurement becomes impossible while tilting the measurement storage part. By arranging the lens at the uppermost portion of the portion and arranging the lens at the inclined portion, it is possible to prevent impurities (drain) such as metal scraps from accumulating around the lens and making it impossible to measure the refractive index.

Further, the pH value measuring means may measure the cooling liquid inside the storage tank or in a flow path arranged separately from the bypass flow path.

As described above, according to the coolant quality management system and the coolant quality detection unit of the present invention, the coolant during actual processing in the metal processing apparatus is measured by various sensors (thermometer, concentration meter, pH meter) and centrally managed externally. It provides a configuration that makes it easy to introduce the system, stabilizes the measurement, and makes it easy to obtain a standardized evaluation against changes in processing conditions, while avoiding physical phenomena that interfere with the operation of various sensors.

A perspective view of a cutting apparatus as an example of a metal processing apparatus using the coolant quality management system and the coolant quality detection unit of the present invention is shown. It is a flow path diagram which shows the supply path of the coolant to the processing tool of a cutting apparatus. An example is a storage tank of a cutting device that separates coolant for measurement with a thermometer, densitometer, and pH meter. (A) is a front view of the embodiment of the coolant quality detection unit, and (b) is a schematic cross-sectional view of the measurement storage unit of the densitometer in the coolant quality detection unit. (A) shows a three-dimensional view having substantially the same viewpoint as that of FIG. 4, and (b) shows a three-dimensional view (top viewpoint) of the upper viewpoint of FIG. FIG. 6 is a schematic perspective view showing another example of the coolant quality detection unit of FIGS. 4 and 5. It is a schematic cross section which shows various examples of the inclination of the measurement storage part of the densitometer arranged in the coolant quality detection unit of FIG. 6, and the positional relationship between the inflow port and the outflow and the lens. It shows the flow of electrical signals until the measured temperature, concentration, and pH values are transmitted to the external unit.

<< Overview of cutting equipment example >>
FIG. 1 shows a perspective view of a cutting device 100 as an example of a metal processing device using the coolant quality detection system of the present invention. The cutting device 100 is generally configured to include a tool holder grip portion 105, a member installation surface 102a to be machined, a work stage 102, a head abutment 108, a head 107, and an operation panel 106. For the members having reference numbers not shown in FIG. 1, refer to FIG. 2 and the like described later.

First, a machining tool such as a drill that causes the tool holder grip portion 105 to make a rotational contact (contact direction = arrow Z direction, rotation direction = arrow Z axial direction) with a member to be machined 109 (see FIG. 2) to be machined. The tool holder 104 holding the 110 (see FIG. 2) is attached. As a result, the tool holder grip portion 105, the tool holder 104, and the machining tool 110 rotate integrally. Further, the member 109 to be processed is placed on the member installation surface 102a on the upper surface of the work stage 102 that moves on the base 103 in the X direction, and is a fixing clamp (not shown) or a fixing bolt (not shown). It is fixed by using> etc.

The operator operates the operation panel 106 to move the work stage 102 in the X direction, and stops and positions the member to be machined at a position where the machining tool 110 is located directly above a desired joining position. Next, the operation panel 106 is operated in a state of being stopped and positioned on the member to be machined, and in addition, the tool 110 is lowered to be brought into contact with the member to be machined, rotated while being in contact with the cutting portion, and in the machining direction. Move repeatedly. The operator inputs each parameter such as the load applied to the machining tool 110 in advance on the operation panel 106, the machining speed of the machining tool 110, the cutting distance per cutting, and the rotation speed of the machining tool 110, and sets the cutting conditions.

When the setting on the operation panel 106 is completed, the machining tool 110 is rotated on the member to be machined to move the head 107 downward in the Z direction according to each parameter set, and the machining tool 110 is moved downward at the cutting start point of the member 109 to be machined. Abut. Further, in the example of FIG. 1, the movement in the Y direction is performed by moving the head abutment 108 in the Y direction at a set moving speed. In the example of FIG. 1, a cutting device 100 is shown in which the X-direction movement is performed by the work stage, the Y-direction movement is performed by the head abutment 108, and the Z-direction movement is performed by the spindle 101. In some cases, the device moves in the Y direction on the work stage 102. After the desired cutting is achieved, the head 107 is moved upward in the Z direction while maintaining the rotation of the machining tool 110, and the machining tool 110 is pulled out from the cutting end point and then the rotation is stopped. Cutting is completed by this process.

<< Example of coolant flow path in processing equipment >>
Subsequently, the supply path of the coolant (hereinafter, also referred to as “coolant”) to the machining tool 110 of the cutting apparatus 100 of FIG. 2 will be described with reference to FIG. Here, the coolant is a cutting fluid having a lubrication function, a cooling function, and the like for the cutting portion, and is a water-soluble cutting oil for measuring the hydrogen ion concentration with a pH meter described later. As shown in FIG. 2, the cutting device 100 includes a storage tank (hereinafter, also simply referred to as “tank”) 112 in which coolant is stored, and a pump for supplying coolant into the cutting device 100 installed in the tank 112. It has 114 and. Further, the cutting device 100 has a valve unit (coolant supply unit) 122 composed of a plurality of solenoid valves 116, 118, 120 and the like. The valve unit 122 has an input flow path 124 connected to a discharge port (output port) of the pump 114. In the input flow path 112, a relief valve 126 is connected to the discharge flow path 124a immediately after the discharge port of the pump 114, and a surplus flow rate input to the valve unit 122 to the relief valve 126 (this is from the flow rate from the pump 114). , Equal to the flow rate obtained by subtracting the flow rate required for the valve unit 122) is connected to the drain flow path 128 that returns the valve unit 122 to the inside of the tank 112 to control the flow rate input to the valve unit 122.

Further, the first supply path 130, the second supply path 132, and the third supply path 134 are connected to the input flow path 112 that has passed through the relief valve 126. Each of the supply paths 130, 132, and 134 is composed of check valves 136, 138, 140, electromagnetic switching valves 116, 118, 120 and check valves 142, 144, 146. The output flow path 148 connected to the first supply path 130 is connected to an injection nozzle (injection means) 154 for injecting coolant. Similarly, the output flow path 150 connected to the second supply path 132 is via the head 107 (or the head abutment 108), the tool holder grip portion 105, and the connection flow path 150 formed in the tool holder 104. , Is connected to a machining tool 110 such as a rotary tool. The processing tool 110 is provided with through holes (oil holes: not shown) from the upper end to the lower end, and communicates with the connection flow path 150. Further, the output flow path 152 connected to the third supply path 134 similarly grips the tool holder via the head 107 and the like and the connection flow path 152 formed in the tool holder gripping portion 105 (or in the tool holder 104). It is connected to the port (not shown) at the lower end of the part 105 (or the tool holder 104).

In order to control the operating state of the electromagnetic switching valves 116, 118, 120 of the valve unit 122, the cutting device 100 is provided with a control unit 160 including a CPU, a memory, a drive circuit, and the like. The control unit 160 controls the electromagnetic switching valves 116, 118, 120 to the communicating state or the shutoff state according to a predetermined control program. When the electromagnetic switching valves 118 and 120 of the second supply path 132 and the third supply path 134 are switched to the communication state, the coolant discharged from the pump 114 is connected from the second supply path 132 and the third supply path 134. It is supplied to the machining tool 110 from the inside or the outside of the machining tool 110 via 150 and 152. On the other hand, when the electromagnetic switching valves 118 and 120 of the second supply path 132 and the third supply path 134 are switched to the shutoff state, the coolant is shut off in the second supply path 132 and the third supply path 134.

When the valve unit 122 is controlled in the state of communicating with the second supply path 132 (first state) in this way, the coolant passes through the machining tool 110 and is discharged from the coolant hole at the lower end. Further, when the valve unit 122 is controlled in a state of communicating with the third supply path 134 (second state), the coolant passes through the tool holder grip portion 105 (or the inside of the tool holder 104) from the coolant hole at the lower end. It is sprayed onto the processing tool 110. On the other hand, when the valve unit 122 is controlled so as to shut off the second supply path 132 and the third supply path 134, the discharge / injection of the coolant from the respective coolant holes is stopped.

When the electromagnetic switching valve 116 of the first supply path 130 is switched to the communication state, the coolant discharged from the pump 114 is supplied to the injection nozzle 154 via the first supply path 130 and the output flow path 148. Then, the coolant supplied to the injection nozzle 154 is injected from the outside toward the member 109 to be processed and the processing tool 110.

<< Separation of coolant and measurement of temperature, concentration, and pH value of the separated coolant >>
The quality evaluation of the coolant in the metal processing apparatus is performed based on the data obtained by measuring (detecting) the temperature, concentration, and pH value of the coolant at predetermined periods (every predetermined time, every predetermined period, etc.). In this coolant quality detection system, the coolant measured by the thermometer, the densitometer, and the pH meter, which are means for measuring the temperature, concentration, and pH value, is separated from the tank 112. Here, the thermometer is manufactured by Nippon Densoku Co., Ltd., the densitometer is "CM-BASEα (A)" manufactured by Atago Co., Ltd., which converts the concentration by using the change in the refractive index of light, and the pH meter is the conductivity ( The hydrogen ion concentration is estimated using the change in electrical resistance) using the "Handy pH Meter SK-620PH II" manufactured by Sato Keiki Seisakusho Co., Ltd., and the digitized temperature signal, concentration signal, and pH value signal, respectively. Is sent externally. In consideration of the correction of temperature dependence described later, it is conceivable to utilize the thermometer built in the densitometer or the pH meter as the thermometer.

The coolant separated from the tank 112 for measurement with a thermometer, a densitometer, and a pH meter is a portion of the coolant stored from the tank 112 that has few impurities and can be discharged downstream. It is a supernatant (coolant near the liquid surface) with few impurities. For example, in the example of FIG. 3A, the coolant in the recovery flow path 153 in the apparatus is discharged (drained) into the tank 112 (arrow 1 in FIG. 3A), and the coolant outlet is near the center of the side portion of the tank 112. 113 is provided to measure the temperature, concentration, and pH value of the coolant discharged from the outlet 113 (arrow 2 in FIG. 3A). Impures such as cutting chips mixed in the coolant in the tank 112. (The lower "drain" in FIG. 3 (a)) is settled at the bottom, and the floating oil composed of the water-insoluble component is accumulated in the upper part (the upper "floating oil" in FIG. 3 (a)). However, by separating only the coolant in the intermediate layer between the floating oil and the drain, only good coolant can be measured, and dirt on the densitometer, clogging of the pH meter, etc. can be avoided.

Further, in the tank 112, as shown in FIGS. 3 (b) and 3 (c), a plurality of containers may be installed in multiple stages in the vertical direction, and a good cooling liquid in the container on the upstream side may be poured to the downstream side. In the case of FIG. 3B, first, the coolant in the recovery flow path 153 in the apparatus is discharged into the container 112a (arrow 3 in FIG. 3B), and the relatively good coolant once stored in the container 112a flows. It is discharged from the outlet 113a to the lower container 112b ((FIG. 3 (b) arrow 4). The outlet 113a is from the liquid level to the bottom in the container 112a in which the coolant of the intermediate layer between the floating oil and the drain is present. Located near the center of the height. The coolant released into the lower container 112b is temporarily stored in the container 112b, and as in the case of the container 112a, a better coolant is discharged from the outlet 113b to the lower container 112c. (FIG. 3 (b) Arrow 5). At this stage, the coolant contains almost no floating oil or drain, and good coolant in the lower container 112c is discharged from the outlet 113c (FIG. 3 (b). ) Arrow 6), this coolant is measured with a thermometer, densitometer, and pH meter. In this example, impurities (drain) such as water-insoluble floating oil and cutting chips are generated each time the coolant is discharged from the upstream to the lower container. Will be removed.

Further, in the example of coolant preparation shown in FIG. 3C, a container 112d having a raised floor is installed from the bottom in the container 112e, and the coolant in the recovery flow path 153 in the apparatus is first discharged into the container 112d ( FIG. 3C, arrow 7), the coolant once stored in the container 112d, excluding most of the floating oil and drain, is discharged from the outlet 113d to the lower container 112c ((FIG. 3C). ) Arrow 8). The coolant discharged into the lower container 112e is stored in the container 112e, and only the better coolant is discharged from the outlet 113e (FIG. 3 (c) arrow 9), and the water-insoluble insoluble oil. The coolant after removing impurities such as cutting chips and cutting chips is measured with a thermometer, a densitometer, and a pH meter. Note that the outlets 113d and 113e are the floating oil in the container 112d like the outlet 113a and the like. It is located at the position where the coolant in the intermediate layer with the drain exists, that is, between the bottom and the liquid level.

<< About the example of the first coolant quality detection unit >>
Next, a specific example of the first coolant quality detection unit 1 for measuring the coolant separated from the tank 112 will be described. 4 to 5 are views showing one of the main configuration examples of the embodiment of the coolant quality detection unit, FIG. 4 is a front view, and FIG. 4B is a densitometer in the coolant quality detection unit. 5 (a) shows a schematic cross-sectional view of the storage unit for measurement, FIG. 5 (a) shows a three-dimensional view having substantially the same viewpoint as FIG. 4, and FIG. 5 (b) shows a three-dimensional view (top viewpoint) of the upper viewpoint of FIG. ing. It should be noted that FIGS. 4 to 5 show only the members necessary for assisting the understanding of the description of each member described later, and some members are omitted depending on the drawings (also in FIGS. 6 to 7 described later). Similarly). The coolant quality detection unit 1 generally includes a pH meter 9, a concentration meter 11, a pedestal 23, a storage tank 21, and a suction pump 24. The thermometer 10 may be separately arranged in the coolant quality detection unit 1, or a thermometer built in the densitometer 11 or the pH meter 9 may be used as described later.

The coolant quality detection unit 1 is arranged in the middle of a bypass flow path (not shown) separated from the tank 112. The "bypass flow path" from which the coolant of the tank 112 is separated is a bypass flow path dedicated to measurement, which is different from the circulation system of the processing apparatus 100, and the coolant quality detection unit 1 is interposed in the middle of the bypass flow path. Alternatively, the coolant quality detection unit 1 may be directly connected to the supernatant of the coolant in the tank to flow in and out. First, the coolant in the tank 112 is sucked by the suction pump 24. The suction pump 24 is driven by the electric motor 24a to operate the drive unit 24b intermittently according to the measurement timing (for example, it operates every 10 minutes). In the present coolant quality detection unit 1, the suction pump 24 is fixed to the outer frame 2 with the drive unit 24b on the outer side and the electric motor 24b on the inner side. The coolant sucked from the tank 112 is sucked by the suction pump 24 as shown by the arrows circles 1 to 2 in FIG. 4A, and is carried into the coolant quality detection unit 1 (inside the outer frame 2).

The coolant sucked by the suction pump 24 flows into the measurement storage unit 11c from the inflow port 11a of the densitometer 11 (see the arrow circle 3). FIG. 4B is a schematic cross section showing the inflow and outflow of coolant into the measurement storage portion 11c of the densitometer 11. The measurement storage unit 11c has a conical trapezoidal shape with a small tip, and a lens (prism) 24 (made of sapphire) for concentration measurement is arranged in the center. The coolant flowing in from the inflow port 11a of the measurement storage unit 11c is discharged toward the lens 24, goes around the inner wall of the conical trapezoid, and does not collect metal debris in the coolant on the lens 24, and the outflow port reduces the speed of the coolant. It is discharged from 11b. At this time, the refractive index of the light of the coolant in the measuring reservoir 11c is measured by the lens 24, and the concentration is converted from the change.

The densitometer 11 is mounted on the upper part of the support plate 25 that stands up from the bottom of the outer frame 2. In the example of FIG. 4A, the upper part of the support plate 25 is inclined to the lower right, but this inclination angle is the speed and inclination angle of the coolant flowing in and out of the measurement storage part 11c, and the measurement storage part 11c. It is changed according to the shape and the like, and may rise in the direction of arrow A as compared with the example of FIG. 4A.

Further, the inner wall of the measurement storage unit 11c is a reflector, and if cutting chips or the like in the coolant adhere to the inner wall, the measurement accuracy of the densitometer 11 deteriorates. Therefore, as shown in FIG. 4B, the inflow port 11a and the outflow port 11b of the measurement storage unit 11c have an inflow port and an outflow port for cleaning in addition to the inflow port and the outflow port at the time of measurement (normal time), respectively. Have. The inflow port and outflow port for cleaning merge with the inflow port and outflow port at the time of measurement (normal time), and when the coolant is discharged into the storage unit 11c for measurement, at the time of measurement (normal time) and at the time of cleaning. Both are discharged from the same flow path and the same position. This is because it is preferable to follow the same flow path for cleaning because it is cutting debris or the like that has adhered according to the flow of coolant during measurement (normal time). Further, of the inflow port 11a and the outflow port 11b, the cleaning side (see "cleaning IN" and "cleaning OUT" in FIG. 4B) is from the flow path leading to the measurement storage unit 11c and the measurement storage unit 11c. The flow path to the outside, that is, the approach section is made substantially straight to avoid a decrease in the flow velocity of the washing water of the jet. On the other hand, at the time of measurement (normal time: see "normal IN" and "normal OUT" in FIG. 4B), the inflow port and the outflow port bend the approach section to reduce the flow velocity.

The coolant that has flowed into the measurement storage unit 11c is discharged from the lower outlet 11b (see the arrow circle 4) and flows into the upper part of the storage tank 21 (see the arrow circle 5). As shown in FIG. 5, the storage tank 12 is a tubular member that opens upward, and is mounted on a pedestal 23 installed at the bottom of the outer frame 2 in a raised floor shape. The opening above the storage tank 12 is closed by the lid member 22, and a through hole provided in the lid member 22 (or a through hole above the side of the storage tank 21 or the like) is used as an inflow port for coolant. Further, the lid member 22 is provided with a through hole in the center and carries the pH meter 9 through the through hole. The flow velocity of the coolant flowing into the storage tank 22 decreases as it passes through the storage tank 21, and cutting chips and the like settle. Therefore, the lower end of the pH meter 9 is located on the storage tank 21 so as not to come into contact with the precipitate and make an erroneous measurement. It is arranged with a gap from the bottom. It is preferable that a filter for filtering cutting chips and the like is attached to the inflow portion of the storage tank 21 (for example, in the vicinity of the through hole of the lid member 22). Then, a flow rate sensor can be provided in the flow path before and after the inflow and outflow to and from the storage tank 21, and when the decrease in the flow rate is measured, clogging can be detected.

Then, the pH value of the coolant flowing into the storage tank 21 is detected by measuring the conductivity of the coolant with the pH meter 9 and estimating the hydrogen ion concentration, and flows out from the lower outlet 21b (see FIG. 5B). (See arrow circle 6). The coolant flowing out of the storage tank 21 flows into the bypass flow path to the tank 112 and is returned to the tank 112. In the coolant quality detection unit of FIGS. 4 to 5, the coolant is in the order of the suction pump 24, the concentration meter 11, and the storage tank 21 (arrow circle 1, circle 2, circle 3, circle 4, circle) as described above. It flows in the order of 5 and 6), but it flows in the order of suction pump 24, water tank 21, and densitometer 11 (arrow circle 1, circle 2, circle 5, circle 6, circle 3, circle 4). Is also good.

Further, in the coolant quality detection unit 1, the temperature measurement target by the thermometer 10 may be the coolant in the tank 112, but the thermometer 10 is built in the densitometer 11 and the pH meter 9, and the thermometer 10 is built-in. In some cases, the measured temperature is output at the same time as the concentration or pH value is measured with the thermometer 10. Based on this temperature information, the concentration and pH value measured by the respective densitometer 11 and the pH meter 9 are corrected so that the temperature dependence is eliminated. This correction may include a correction for converting the reference temperature of the densitometer 11 and the pH meter 9 into the concentration and pH value at the reference temperature of both. In addition, temperature measurement may be performed by measuring the "room temperature (atmospheric temperature)" that affects the decay of the coolant with a thermocouple attached to the receiver, and data may be collected. Taking this temperature information into consideration, the concentration and pH value may be collected. In some cases, the temperature dependence is eliminated.

Further, in the measurement of the pH value, the storage tank 21 to which the pH meter 9 is attached is made of an electrically insulating material, or the coolant liquid inside the storage tank 21 is electrically floated (non-electrically conductive). Due to the circulation of cutting oil, the cutting oil electrically connected to the external device and the cutting oil whose pH value is to be measured form a circuit, and the potential in the tank does not fluctuate, making measurement with a pH meter impossible or impossible. , The occurrence of the phenomenon that the error becomes large is suppressed.

The "charge due to static electricity" generated by the flow of cutting oil in the piping may also affect the pH measurement result, and when measuring the pH value and / or concentration, the flow of the coolant liquid Is preferable in order to ensure the accuracy of the measured values of pH value and / or concentration.

<< About the second coolant quality detection unit example (miniaturization example) >>
Next, a specific example of the second coolant quality detection unit 1'that measures the coolant separated from the tank 112 will be described with reference to FIGS. 6 to 7. In FIGS. 6 to 7, the same type of members will be described with the same reference numbers. 6 to 7 are views showing one of the main configuration examples of the embodiment of the second coolant quality detection unit 1', and FIG. 6 is a three-dimensional view showing the inside of the unit as in FIG. It is a perspective view. It should be noted that FIGS. 6 to 7 show only the members necessary for assisting the understanding of the description of each member described later, and the members and the like not particularly mentioned are substantially the same as those of FIGS. 4 to 5.

Unlike the first coolant quality detection unit 1, the second coolant quality detection unit 1'is an example of achieving miniaturization of the entire unit in consideration of the space around the tank 112, and stores the pH meter 9. The pH is measured by directly inserting it into the tank 112 or the like instead of the tank 21 (see FIG. 4B for an example of insertion). When attempting to miniaturize the unit, if the configuration of the first coolant quality detection unit 1 is miniaturized as it is, it is necessary to obtain power supply to the pH meter 9 and the densitometer 11 from a common power source. In that case, the pH meter There was a problem that the measured potential of No. 9 was out of order, but it was found that the cause was that the ground potential was out of order due to the influence of the common power supply and the potential shift due to the liquid connection occurred. Therefore, in the second coolant quality detection unit 1', the pH meter 9 is not arranged in the unit, but is inserted directly into the tank 112 or into the flow path separated from the tank 112 by a separate power source for measurement. And said. Since the pH meter 9 is not arranged in the second coolant quality detection unit 1', the storage tank 21 is also not arranged, and as a result, a certain degree of miniaturization is achieved (see FIG. 6).

Furthermore, in the second coolant quality detection unit 1', the flow direction of the coolant is also improved in order to eliminate the harmful effects of miniaturization due to the elimination of the pH meter 9 and the storage tank 21 and to achieve further miniaturization. .. Specifically, the inclination of the densitometer 11 and the positions of the inflow port 11a and the outflow port 11b are different. The coolant in the tank 112 is sucked by the suction pump 24. In the present coolant quality detection unit 1', the coolant sucked from the tank 112 is sucked by the suction pump 24 as shown by the arrow circles 1'to 2'in FIG. 6, and is inside the coolant quality detection unit 1'(outer frame). It is carried to (inside 2).

The coolant sucked by the suction pump 24 flows into the measurement storage unit 11c from the inflow port 11a of the densitometer 11 (see arrow 3). FIG. 7A is a schematic cross section showing the inflow and outflow of coolant into the measurement storage unit 11c of the densitometer 11 (unlike FIG. 4B showing only the portion of the measurement storage unit 11c, the entire densitometer 11). (Shows a perspective sectional view of). As described above in FIG. 4B, the measurement storage unit 11c has a conical trapezoidal shape with a small tip, and a lens (prism) 24 for concentration measurement is arranged at the center (recess in the center) and flows in from the inflow port 11a. The resulting coolant is emitted toward the lens 24, the refractive index of the light of the coolant is measured by the lens 24, and the concentration is converted from the change.

When the inflow port 11a is tilted so as to be located below the lens 24 as shown in FIGS. 4 (b) and 7 (b), metal debris in the coolant is unlikely to collect in the lens 24 as described above. On the other hand, since the generation of air bubbles can be suppressed, foamy floating oil is generated above the oil surface, and when this reaches the lens 24, it becomes an obstacle to the measurement of the refractive index. In the case of the configuration of 4 (b) and FIG. 7 (b), there is a problem that it is difficult to extract the floating oil from the outlet 11b by normal convection.

On the contrary, when the inflow port 11a is simply arranged above the lens 24 as in the lens 24 as shown in FIG. 7C, the above-mentioned problem that the floating oil does not come out does not occur, but the lens 24 There is a problem in that metal scraps in the coolant tend to collect.

Advantages and problems of the inclination of the measurement storage unit 11c and the position of the lens 24 in FIGS. 4 (b) and 7 (b), and the inclination of the measurement storage unit 11c and the lens 24 in FIG. 7 (c). 6 and 7 (a) show an example in which the advantageous points and problems of the position are contrary to each other and the balance between the advantageous points and the problems of both is taken into consideration. In the examples of FIGS. 6 and 7A, the measurement storage unit 11c is tilted by about 45 °, and the measurement storage unit 11c is 45 so that the inflow port 11a and the outflow port 11b are both located above the lens 24. It is arranged at an angle of about ° (inclined in the direction of arrow B). In the case of this configuration, since the lens 24 is arranged at the inclined portion, the metal debris in the coolant is unlikely to collect on the lens 24, and at the same time, the outlet 11b is located at the uppermost point, so that the floating oil is easily discharged.

See FIG. 6 again. The coolant that has flowed into the measurement storage unit 11c is discharged from the upper outlet 11b (see the arrow circle 4'), and the coolant is transported using the upper space due to the measurement storage unit 11 being arranged below. (Refer to the arrow circle 7'). In the example of FIG. 6, since the pH meter is not built in, the pH meter is discharged downward as it is (see the arrow circle 8').

<< About external transmission >>
Next, the transmission of the temperature information, the concentration information, and the pH value information measured by the coolant quality detection unit 1 (1') of FIGS. 4 to 7 to the outside will be described. In FIG. 8, the flow of the electric signal until the measured temperature, concentration, and pH value are transmitted to the external unit 16 will be illustrated and described. In this example, the flow of electric signals is generally shown from the pH value detecting means (pH meter) 9, the temperature measuring means (thermometer) 10, and the concentration measuring means (concentration meter) 11. The temperature measuring means 10 may be built in the coolant quality detection unit 1 as shown in FIGS. 4 to 7 or may be installed in the tank 112, and the pH value detecting means 9 and the concentration measuring means (concentration meter). ) 11 itself may be built in (in either case, the temperature measuring means 10 can be said to be a component of the coolant quality detection unit 1). As for the pH value detecting means 9, FIG. 8 shows an example in which the pH value detecting means 9 is built in like the coolant quality detecting unit 1 of FIGS. 4 to 5, but the pH value detecting means 9 is Like the coolant quality detection unit 1'in FIG. 7, it may be installed in the tank 112 without being built in.

The signals from the pH meter 9, the thermometer 10, and the densitometer 11 described above are converted into digital signals and output. The temperature measuring means 10 in FIG. 8 is a temperature receiving unit that typically uses a thermocouple to output a digital signal by a control circuit in the device via a potential difference amplifier or an A / D converter. Further, the output signals from the pH value measuring means 9, the temperature measuring means 10, and the concentration measuring means 11 are received by the controller 14 of the transmission unit 13 provided in the cutting device 100 or connected by wire, and are externally connected by the wireless transmission device 15. Is transmitted wirelessly to. Further, the coolant quality detection unit 1 is shown in FIGS. 4 to 7.
As shown in the above, a pump (suction pump) 24 for sucking coolant from the tank 112 is provided. The pump 24 is an electric type and operates intermittently, and an appropriate intermittent signal is transmitted by the controller 14 of the transmission unit 13 that has received the output signals from the pH value measuring means 9, the temperature measuring means 10, and the concentration measuring means 11. To operate the pump 24.

Further, the wirelessly transmitted temperature information, pH value information, and concentration information output signals are received by the wireless receiving device 17 of the external unit 16. The wireless communication standards between the wireless transmitting device 15 and the wireless receiving device 17 shown by the broken lines in FIG. 8 are Wi-Fi (Wireless Fidelity), Bluetooth (Bluetooth), wireless LAN (Local Area Network), and ZigBee. Etc. can be used. The external unit 16 may be an example of a storage / arithmetic unit 19 such as a no-computer computer including a wireless receiving device 17, but in the example of FIG. 8, a dedicated wireless receiving device 17 is separately installed and connected to the external unit 16 by a USB port. Then, the signal is received by the storage / arithmetic unit 19. Then, an image is displayed, printed, or the like on an output device 20 such as a display or a printer.

Further, in FIG. 8, the coolant quality detection unit 1 and the transmission unit 13 are shown in separate blocks, but the transmission unit 13 may be included in the coolant quality detection unit 1. For example, the transmission unit 13 may be included in the outer frame 2 of the coolant quality detection unit 1 shown in FIGS. 4 to 5. Further, the temperature measuring means 10 may be provided separately from the coolant quality detection unit 1, a thermocouple is inserted into the tank 112, and the temperature is digitally measured by the control circuit in the device via the potential difference amplifier and the A / D converter. A temperature receiving unit that outputs a signal may be provided.

Although the embodiments of the present invention have been described above, the present invention is not limited thereto, and it will be clear to those skilled in the art that various modifications and improvements included in the present invention may exist. .. The metal processing device that measures the coolant with the coolant quality management system and the coolant quality detection unit of the present invention has been described by exemplifying a cutting device, but other metals that circulate the coolant in the metal processing device have been described. Processing equipment, such as grinding equipment and electric discharge machining equipment, is also included.

1,1'coolant quality detection unit
2 outer frame
9 pH value measuring means (pH meter)
10 Temperature measuring means (thermometer)
11 Concentration measuring means (concentration meter)
13 Transmitter
14 controller
15 Wireless transmission device
16 External unit
17 Wireless reception device
18 serial USB converter
19 Recording / Arithmetic Logic Unit
20 Output device
21 Water tank
22 Lid
23 pedestal
24 suction pump
25 Support plate
100 cutting equipment
101 spindle
102 work stage
102a Tread of the member to be machined
103 base
104 Tool Holder
105 Tool holder grip
106 Operation panel
107 head
108 head abutment
109 Work member (work)
110 Machining tool
112 Storage container (tank)
112a, 112b, 112c, 112d, 112e container
113 Outlet
114 Coolant supply pump (pump)
116, 118, 120 Electromagnetic switching valve
122 Valve unit (coolant supply unit)
124 Input flow path
124a Discharge flow path
126 relief valve
128 Drain flow path
129 Filter (filtration means)
130 1st supply route
132 Second supply route
134 Third supply route
136, 138,140 Check valve
142,144,144 throttle valve
148,150,152 Output flow path (connection flow path)
154 Injection nozzle (injection means)
160 control unit

Claims (11)

A coolant quality management system that detects the quality of the coolant that cools the machining tool while the metal processing equipment is operating or stopped, and at least
The temperature, concentration, and / or pH value of the cooling liquid in the intermediate layer from the bottom to the liquid level in the cooling liquid storage tank in the cooling liquid supply flow path is separated at predetermined time or period. A temperature measuring means, a concentration measuring means, and / or a pH value measuring means are provided.
The concentration measuring means measures the concentration by converting the concentration into a concentration based on the change in the refractive index of the light of the separated coolant, and the pH value measuring means changes the conductivity of the separated coolant. Measure the pH value by estimating the hydrogen ion concentration based on
A coolant quality management system that simultaneously measures the separated coolant by the temperature measuring means, the concentration measuring means, and / or the pH value measuring means. The coolant quality management system according to claim 1, wherein the temperature measuring means includes a separate thermometer and / or a built-in thermometer of the concentration measuring means and the pH value measuring means. The storage tank is composed of a plurality of containers having different liquid levels and opened upward.
The quality of the coolant according to claim 1 or 2, wherein the coolant discharged to the outside from the outlet of the container on the upstream upper side is poured into the container on the downstream lower side when the coolant in the storage tank is separated. Management system. The measurement of the concentration measuring means and the pH value measuring means is performed in a state where there is no flow of the coolant or fluctuation in the liquid level and / or in a state where the flow of the coolant is stopped, any one of claims 1 to 3. Coolant quality management system described in. In the coolant quality management system according to any one of claims 1 to 4, the coolant is arranged in a bypass flow path separated from the coolant in the storage tank, and the concentration of the coolant in the bypass flow path and the concentration of the coolant are determined. Concentration measuring means and pH value measuring means for measuring pH value, respectively,
A storage tank for storing the coolant in the bypass flow path and
A coolant quality detection unit including a suction pump for sucking the coolant in the storage tank. A replaceable filter that filters the coolant in the bypass flow path and
The coolant quality detection unit according to claim 5, further comprising a flow rate sensor for measuring the flow rate of the coolant in the bypass flow path. The storage tank is arranged in a raised floor in the coolant quality detection unit, and the coolant in the bypass flow path flows in from the upper inflow port of the storage tank and is discharged from the lower outflow port. , The coolant quality detection unit according to claim 5 or 6. The concentration measuring means is provided with a measuring storage unit for storing a cooling liquid and measuring the refractive index of light.
The measurement storage unit has an inflow port for the cooling liquid to flow in and an outflow port for the cooling liquid to flow out, and each of the inflow port and the outflow port measures the concentration of the cooling liquid in the measurement storage unit. It is provided with a normal inflow port and a normal inflow port for cleaning, a cleaning inflow port and a cleaning inflow port for cleaning the inside of the measurement storage part, and the cleaning inflow port and the cleaning outflow port are respectively from the end. Claims 5 to 5, wherein the flow path leading to the measurement storage portion is a substantially straight line, and each of the normal inflow port and the normal use outlet is provided with a curved portion in the flow path from the end portion to the measurement storage portion. 7. The coolant quality detection unit according to any one of 7. The coolant according to any one of claims 5 to 8, wherein the pH value measuring means is mounted on the storage tank to measure the cooling liquid inside the storage tank, and the storage tank is made of an electrically insulating material. Good / bad detection unit. In the coolant quality management system according to any one of claims 1 to 4, the concentration of the coolant in the bypass flow path is determined by being arranged in the bypass flow path separated from the coolant in the storage tank. Concentration measuring means to measure and
A suction pump for sucking the coolant in the storage tank is provided.
The concentration measuring means measures the refractive index of the light of the coolant with a lens disposed inside by allowing the coolant to flow in and out of the measuring reservoir arranged in the bypass flow path, and the measurement is performed. The storage unit is a coolant quality detection unit in which the outlet of the coolant is located at the uppermost portion and the lens is tilted and positioned so as to be arranged on the tilted portion. The cooling liquid quality detection unit according to claim 10, wherein the pH value measuring means measures the cooling liquid inside the storage tank or in a flow path arranged separately from the bypass flow path.

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