DE102013021413A1 - Method for coolant supply and corresponding tool supply device - Google Patents

Abstract

In a tool supply device (1) with a p / Q-controlled pump (2) for supplying at least one tool (3, 3 ') with coolant is proposed, in an operating phase (III) a flow control valve (7, 7') in a activate at least one tool (3, 3 ') supplying flow path (6, 6') in order to promote a constant quantity of operating coolant on the at least one tool (3, 3 '), the operating phase (III) being filled ( I), in which a supply line (25, 25 ') of the tool (3, 3') is pressure-controlled filled, and / or a learning and / or test phase (II) in which the operating coolant quantity of the operating phase (III) pressure-controlled determined and / or checked, upstream / are.

Description

The invention relates to a method for supplying coolant to at least one tool, wherein the at least one tool is supplied with coolant to a coolant supply device via a p / Q-regulated pump, the pump providing a primary pressure on the output side and generating a working pressure on the at least one tool.

The invention further relates to a tool supply device with a p / Q-controlled pump for supplying at least one tool with coolant.

It is known to supply tools during the drilling or other machining operation with coolant. The present invention is based on the known supply via internal channels in the tool. In DE 10 2011 013 151 A1 and DE 10 2006 052 602 A1 It is described that it is advantageous to convey the coolant in a quantity-controlled or quantity-controlled manner in order to operate a tool supply device in an energy-efficient manner. Especially in deep hole drilling, it has been found that a certain amount of time has to be waited until a stationary or stable state is reached during operation.

The invention is based on the object of improving the process until it reaches a stationary and / or stable operating phase in a method for supplying coolant to at least one tool.

To achieve this object, the features of claim 1 are provided according to the invention. In particular, it is thus proposed according to the invention in a method of the type described above that in a filling phase, the coolant supply device is operated pressure controlled until the working pressure at the at least one tool reaches or exceeds a working threshold, and that after completion of the filling phase in an operating phase downstream of the pump Flow control valve is activated to promote at the at least one tool a constant amount of operating coolant. The pressure-controlled operation can be characterized in such a way that the primary pressure is set or specified without recirculation. The advantage here is that the time required to reach a steady state operation is shortened. It is furthermore advantageous that after the filling and, if appropriate, further preparatory phases or measures, the operating phase can be carried out in a resource-saving manner. Because of the activated flow control valve a required amount of coolant is exactly complied with. Coolant quantities are to be understood in this description always referring to a unit of time. In the operating phase can therefore be promoted volume controlled. No energy is used to keep the primary pressure unnecessarily high. The increase in the working pressure indicates that the coolant has arrived at a constriction formed by the at least one tool and that the filling process is thus completed. The operating phase may immediately follow the filling phase, or further, for example preparatory, phases may be run through before the operating phase begins.

In general, the working pressure can be characterized as a pressure that prevails on the tool and is measured and / or monitored with a pressure sensor arranged on the tool. The primary pressure can be characterized as a pressure that prevails directly on the output side of the pump and is preferably adjustable with a control circuit of the p / Q-controlled pump.

In an advantageous embodiment, it can be provided that the filling phase begins with a filling operation of an at least partially empty supply line to the at least one tool. The advantage here is that the partially or even completely empty supply line can be filled very quickly.

In an advantageous embodiment it can be provided that the pump is operated under pressure pressure with a constant primary pressure. Preferably, a primary pressure is preset or set, which results from a maximum allowable pressure on the at least one tool. Thus, an already mentioned filling of supply lines can be done quickly. This is an advantage, for example, when changing tools and saves time for retooling.

In an advantageous embodiment, it may be provided that the flow control valve is opened and / or deactivated in the filling phase. The advantage here is that delays in the filling phase can be avoided. Preferably, the flow control valve is fully opened to oppose the filling process with a flow resistance that is as small as possible.

Conversely, it may alternatively or additionally be provided that a reduced opening cross-section is set at the flow control valve in the operating phase with respect to the filling phase. The advantage here is that with the flow control valve a volume control is feasible. The reduction of the opening cross section can be done, for example, by or during activation of the flow control valve. Preferably, the opening cross section for flow control is variably adjustable.

In one embodiment of the invention of possibly independent inventive quality can be provided that in the operating phase, a load pressure feedback to the pump is switched from a tapping point in front of the flow control valve to a tap point behind the flow control valve. The advantage here is that a reference point for the load pressure feedback behind the flow control valve is displaced, so that when activated flow control valve coolant losses in the flow control valve due to leaks have little or no influence on the control of the primary pressure. By relocating the load pressure feedback downstream of the flow control valve, the pressure drop across the flow control valve can be maintained at a desired value. Thus, a volume control of the smallest amounts even with simple valve technology, such as with slide valves, feasible.

In this case, it is preferably provided that a pressure difference corresponding to a pressure drop across the flow control valve is added to the load pressure return after switching, that is to say in the case of a return from the tapping point downstream of the flow control valve. The advantage here is that when activated flow control valve, a desired pressure behind the flow control valve is adjustable without unnecessarily high pressures must be set before the flow control valve. This saves energy during operation. The invention thus additionally makes it possible to detect tool breakage or tool blockage by continuously measuring the working pressure.

It is particularly advantageous in this case if the load pressure feedback influences a control point for the primary pressure provided on the output side. Thus, a p / Q control of the pump can be used to compensate for pressure fluctuations - for example due to flow resistance changes to the tool - on at least one tool. The return to a control point of the pump controller allows in a particularly simple manner adding the said pressure difference.

Alternatively or additionally, in this case or in the case of an embodiment of independent inventive quality, it may be provided that during load pressure return, a maximum pressure is formed from working pressures applied to at least two tools and / or load pressures present behind at least two flow control valves. The advantage here is that a supply of more than one tool, for example, two, three or more than three tools, with a control loop is adjustable.

In one embodiment of the invention can be provided that the primary pressure is raised in the operating phase compared to the filling phase. The advantage here is that a sufficiently high pressure at the flow control valve can be provided in order to realize a fast response and readjusting flow control. Another advantage is that a pressure drop due to a flow control on the flow control valve can be compensated.

In one embodiment of the invention can be provided that at the beginning of the operating phase in a Zuschaltphase first increases the primary pressure by one level and then the or a load pressure return to the pump is switched from a tap point before the flow control valve to a tapping point behind the flow control valve. The advantage here is that a transient when changing to the volume control can be reduced or shortened. A further advantage is that a pressure drop across the flow control valve in a simple manner in the control loop of the load pressure feedback is taken into account by the corresponding pressure difference is added to a pressure signal of the load pressure feedback. It is favorable if the primary pressure is increased by a further step to the final value for the operating phase after activation of the load pressure feedback. Preferably, the connection phase is performed after the activation of the flow control valve. Thus, the amount control of the operating refrigerant amount can quickly reach a steady state.

Alternatively, in a method of the type described at the outset for solving the stated problem, it is proposed that in a learning and / or test phase an operating coolant quantity assigned to the at least one tool be determined and / or tested and that after completion of the learning and / or or test phase in a phase of operation, a downstream of the pump flow control valve is activated in order to promote at the at least one tool, the operating coolant amount constant over time. The advantage here is that an operating coolant quantity is adjustable and / or verifiable before being controlled in the operating phase to this operating coolant quantity. Thus, a tool supply device on which the method is carried out can be set up for a new tool or for new tools, or a functionality of the at least one tool can be checked before use. In the operating phase, the quantity-controlled delivery already described can thus be realized.

For example, it can be provided that the learning and / or test phase is carried out between the filling phase and the operating phase. The advantage here is that the operating coolant quantity can be measured at filled supply lines.

In an advantageous embodiment it can be provided that in the learning and / or test phase pressure-controlled as a function of the working pressure (p _is ) is operated. The advantage here is that stationary or constant conditions for measuring the amount of operating coolant can be created.

It can be provided in an advantageous development that is controlled in the learning and test phase, the primary pressure such that the primary pressure and the working pressure have a predetermined pressure difference. This pressure difference may for example be zero or result from a pressure drop at the flow control valve. The advantage here is that a stationary state of a flow behavior can be achieved, which allows the measurement of the operating coolant amount in a simple manner.

In an advantageous embodiment, it can be provided that the operating coolant quantity is measured or checked in the learning and / or test phase when a coolant quantity delivered at the at least one tool and / or the load pressure assumes / assumes constant values. Thus, an easily monitorable criterion is given when a currently funded coolant quantity is taken over or checked as operating coolant quantity.

In an advantageous embodiment can be provided that a control behavior of the learning and / or test phase is continued unchanged in the operating phase, when the at least one tool associated operating coolant amount is below a predetermined value. It is thus possible to realize a very small amount of delivery, in which a volume control by the flow control valve is not meaningful.

In an advantageous embodiment can be provided that is changed from the Befüllphase directly into the operating phase, if after a predetermined period of time the working threshold is not reached, being set in the operating phase, a predetermined maximum amount as the operating coolant quantity. The advantage here is that too. Tools can be operated with large quantities supply, in which - for example, due to coolant channels in the tool with a large opening cross-section - the pump delivery is not sufficient to cause an increase in the working pressure above the working threshold. The system can thus automatically detect that no operating coolant quantity can be learned or checked. A learning and / or testing phase can thus be skipped, and a preset value can be used as the operating coolant quantity.

In an advantageous embodiment of potentially independent inventive quality can be provided that a first delivery line is used to the at least one tool when the at least one tool associated operating coolant amount is above a threshold, and that automatically to a second delivery line to the at least a tool is changed when the operating coolant quantity is below the threshold, wherein in the first conveying line, a flow meter for an upper measuring range and in the second conveying line, a flow meter for a lower measuring range is arranged. In this case, the lower measuring range is at least partially, preferably completely, below the upper measuring range. The advantage here is that flow meters with different sensitivities and / or accuracies can be used to cover the measuring ranges. Another advantage is that a sensitive flow meter is estimated from damage. Preferably, the switching takes place automatically dependent on pressure or quantity. Alternatively, a pressure regulating valve may be arranged in the first delivery line instead of the flow meter for the upper measuring range. The advantage here is that a pressure control valve has lower procurement costs than a flow meter. Another advantage is that the design effort is reduced. It has been found that with large flow rates, the accuracy of a flow meter and / or a tracking caused by the flow meter is dispensable.

In an advantageous embodiment, it can be provided that a coolant reservoir is filled with the pump, wherein an operating pressure of the coolant reservoir is returned to the pump. The advantage here is that from the coolant reservoir several tools can be supplied. It is particularly favorable if the quantity control of the operating phase takes place on each tool with an individually assigned flow control valve. These flow control valves can in this case be fed from the coolant reservoir. It is a decoupling between the common pump and the respective flow control valves achievable.

In an advantageous embodiment can be provided that, for example, the already mentioned, load pressure feedback of the pump is supplied. Thus, the primary pressure can be influenced.

Alternatively, it can be provided that a, for example, the already mentioned, load pressure feedback of a flow control valve upstream pressure compensator is supplied. This embodiment is advantageous, for example, when the pump fills a coolant reservoir. Thus, one is Controlled pressure at an input of the or each flow control valve can be provided.

To achieve the above object is provided according to the invention in a tool supply device of the type described above, that a flow control valve of the pump is downstream, that the flow control valve deactivatable to provide a constant pressure on the at least one tool and activatable to provide a constant amount of operating coolant to the at least is a tool, and that an activation device is arranged to activate the flow control valve when a working pressure at the at least one tool reaches or exceeds a working threshold. The advantage here is that the tool supply device between different operating modes is automatically switched. For example, when the flow control valve is deactivated, an operating mode can be executed in which a constant working pressure is aimed at on the at least one tool. This is particularly favorable for a fast filling of empty supply lines. When the flow control valve is activated, for example, an operating mode can be executed in which a predetermined, that is to say, for example, a previously measured or predetermined operating coolant quantity is constantly conveyed to the at least one tool. The switchability between a deactivated flow control valve and an activated flow control valve allows a simple and quick change between the operating modes. Thus, multi-consecutive phase methods are feasible. The provision of the constant pressure can, for example, be pressure-controlled without returning the actual working pressure.

In an advantageous embodiment can be provided that the flow control valve, a flow meter is connected downstream. It is advantageous that a measurement of the actually conveyed coolant quantity and / or a tracking of an opening cross-section of the flow control valve can be carried out.

In this case, it may be provided in an advantageous further connection that a control connection is formed between the flow meter and the flow control valve in order to promote a constant operating coolant quantity at the at least one tool and / or track a conveyed coolant quantity. Thus, a volume control is set up. An operating coolant quantity is thus constantly conveyed.

In one embodiment of the invention can be provided that a control unit for deactivatable control of the output side provided by the pump primary pressure is set to or in dependence on the working pressure. The advantage here is that a compensation of a pressure drop across the flow control valve can be set.

In an advantageous embodiment it can be provided that a switching device is provided, with which a load pressure feedback from a tapping point in front of the flow control valve can be switched to a tapping point behind the flow control valve. The advantage here is that the load pressure feedback during operation is switchable to change a reference point for the control behavior. The advantages of a switchable load pressure feedback have already been described above.

It can be provided that the load pressure feedback after switching to the tapping point is acted upon additively by a pressure difference corresponding to a pressure drop across the flow control valve. Thus, a pressure drop across the flow control valve and losses due to leaks in the flow control valve are easy and energetically lowable during operation.

In this case, it can be provided in an advantageous further connection that the load pressure return of the pump or a pressure regulator upstream of the flow control valve is supplied. A load pressure feedback to the pump has the advantage that a control function of the pump can be used. A load pressure feedback to the pressure balance has the advantage that the return is independent of the pump executable. In this case, simply several tools, each with associated load pressure feedback can be supplied via a common pump.

In an advantageous embodiment, it can be provided that a load pressure forming device for forming a recirculated load pressure from at least two tools applied working pressures and / or behind at least two flow control valves applied load pressures is established. The advantage here is that several tools can be supplied via a common pump and at the same time a control function of the pump is shared.

In an advantageous embodiment of independent inventive quality can be provided that a first delivery line and a second delivery line are guided to the at least one tool, wherein a switching means for switching from the first delivery line to the second delivery line when a funded operating coolant amount a Threshold below, is set up and wherein in the first delivery line a flow meter with a upper measuring range or a pressure regulating valve and in the second conveying line a flow meter is arranged with a lower measuring range. The advantage here is that a range switching or a connection of a flow measurement for small amounts of coolant can be realized. Thus, the currently funded coolant amount is more accurately detected. The lower measuring range can be arranged completely or at least partially below the upper measuring range.

In an advantageous embodiment it can be provided that the pump is connected to a coolant reservoir, wherein an operating pressure of the coolant reservoir is returned to the pump. The advantage here is that a buffer between the pump and the at least one tool is available. This is particularly advantageous when supplying several tools from a common pump.

In an advantageous embodiment, it can be provided that monitoring means for detecting a reaching of a temporally constant value of a conveyed coolant quantity at the at least one tool and / or the load pressure are set up. Thus, a time is recognizable, to which a meaningful measurement of the delivered amount of coolant can be executed. Thus, a conclusion of a transient and a willingness to enter into a normal operating phase are also automatically recognizable.

Thus, it can be provided that the control unit is arranged for selectively conveying at least two control and / or control behavior from the group of pressure-controlled, pressure-controlled and volume-controlled conveying of coolant to the at least one tool. For example, the control unit may be arranged for selectively pressure-controlled and pressure-controlled conveying in order to carry out the filling phase and the learning and testing phase. Alternatively or additionally, the control unit may be arranged, for example, for selectively pressure-controlled and volume-controlled conveying in order to carry out the learning and testing phase and the operating phase. It is particularly favorable if the control unit is set up for selectively pressure-controlled, pressure-controlled and volume-controlled conveying in order to carry out the filling phase, the learning and test phase and the operating phase. In this case, the invention makes it possible to automatically switch between the control and / or regulating behavior and between the individual phases on the basis of predetermined criteria.

In the tool supply device according to the invention, the flow control valve, in particular the least one flow meter, downstream of a main valve may be present. The advantage here is that the tool supply device is prestressed or biased operable to - to be able to skip the filling phase - for example after a tool change.

It is particularly advantageous if means for carrying out a method according to the invention, in particular as described above and / or according to one of the claims directed to a method, are formed on the tool supply device.

Alternatively or additionally, conversely, provision may be made for the method according to the invention to use a tool supply device according to the invention, in particular as described above and / or according to one of the claims directed to a tool supply device. The advantage here is that an implementation of the method according to the invention can be provided.

The invention will now be described in more detail with reference to embodiments, but is not limited to these embodiments. Further exemplary embodiments result from the combination of the features of one or more claims with one another and / or with one or more features of the exemplary embodiments.

It shows in each case as a simplified circuit diagram for explaining the principle of the invention

1 a tool supply device according to the invention for supplying a tool,

2 a second tool supply device according to the invention, in which more than one tool is supplied from a shared pump,

3 a third tool supply device according to the invention, in which a plurality of tools are supplied from a coolant reservoir,

4 a time sequence of a method according to the invention and

5 an alternative to 1 in which the upper range flowmeter is replaced by a simpler pressure control valve.

1 shows a circuit diagram of a whole with 1 designated tool supply device according to the invention.

The tool supply device 1 has a pump 2 which at least one tool 3 supplied with coolant.

The pump 2 Here, by way of example, it is designed as a volumetric fixed-displacement pump, whose quantity of coolant delivered per unit of time can be adjusted via an eccentricity in a manner known per se. A pump regulator 4 serves in a conventional manner to control the pump 2 to form a p / Q controlled pump. There are other types of pumps instead of the pump 2 usable as a control pump.

The pump 2 puts at an exit 5 thus a primary pressure ready. This primary pressure is via a pressure setting valve 29 adjustable. The primary pressure is when the switching device is deactivated 13 over a first branch 30 a load pressure feedback 14 to the pump regulator 4 (respectively. 4 ' ) returned.

In a flow path 6 between the pump 2 and the tool provided 3 is a flow control valve 7 arranged. The flow control valve 7 is with an activation device 8th switchable between a deactivated state and an activated state. In the right drawing border is the flow control valve 7 shown enlarged with the internal structure.

In the deactivated state, the flow control valve 7 fully open. In the activated state is an opening cross-section 36 of the flow control valve 7 variably adjustable as a function of a drive signal.

In the tool supply device according to the invention 1 becomes the flow control valve 7 from a flowmeter 9 or 10 controlled to the Öffnungsquerschitt 36 of the flow control valve 7 in case of deviations. In the flow control valve 7 is in a conventional manner a pressure compensator 37 formed, which a pressure drop across the opening cross-section 36 constant. Thus, on the tool 3 in the activated state of the flow control valve 7 provided a constant amount of coolant per unit time.

In the deactivated state of the flow control valve 7 becomes the primary pressure at the outlet 5 to the tool 3 passed so that the tool supply device 1 with deactivated flow control valve 7 to provide a constant pressure on the tool 3 is set up.

The tracking of the flow control valve 7 in the activated state through the flow meter 9 respectively. 10 takes place by a control connection, not shown, between the flow meter 9 or the flow meter 10 on the one hand and the flow control valve 7 on the other hand.

A control unit 11 evaluates that with a pressure sensor 12 recorded working pressure on the tool 3 and can monitor it for exceeding a work threshold.

About the first branch 30 the load pressure feedback 14 The generated primary pressure is over a control point 16 returned to the pump to regulate the instantaneous flow rate as a function of the primary pressure. By way of example, the diagram shows pistons for adjusting an eccentricity of the pump 2 shown. However, there are other means for adjusting the current flow rate depending on the type of pump, such as speed control of the pump 2 ' , usable.

The tool supply device 1 is thus also druckgesteuert betreibar. For this purpose, the flow control valve 7 disabled, and it will be on the pressure default valve 29 set a fixed value.

The tool supply device 1 further includes a switching device 13 on, with which a second branch 31 the load pressure feedback 14 is activatable. Thus, the load pressure feedback 14 from a first tap point 32 in front of the flow control valve 7 to a second tap point 33 behind the flow control valve 7 switchable. At the same time the switching device causes 13 or the control unit 11 via a control connection, not shown, that at the control point 16 an additional pressure difference is set, which is a pressure drop across the flow control valve 7 bescheibt. The task of switching the load pressure feedback 14 over the second branch 31 In other words, it is the lowering of the primary pressure to the level of the required load pressure plus pressure offset as well as the limitation of the pressure drop across the flow control valve 7 for leakage minimization.

In the tool supply device 1 is thus on the second branch 31 Switched load pressure feedback 14 in the flow direction behind the flow control valve 7 at the exit 15 applied load pressure to the control point 16 of the pump controller 4 recycled, wherein a pressure difference is added, which corresponds to the mentioned pressure drop.

Thus, with the load pressure feedback 14 the primary pressure at the outlet 5 the pump 2 influenced such that a desired pressure output 15 of the flow control valve 7 is available, regardless of leaks in the flow control valve 7 ,

The activation device 8th and the switching device 13 be through the control unit 11 driven.

The control unit 11 is here set up so that the activation device 8th operated and thus the flow control valve 7 is activated when the working pressure at the pressure sensor 12 reaches or exceeds a working threshold from below.

In the tool supply device 1 is the first flowmeter 9 in a first conveyor line 17 arranged while the second flow meter 10 in a second delivery line 18 is arranged.

Both delivery lines 17 . 18 start behind a switching device 19 passing over the flow path 6 from the pump 2 is supplied.

The switching device 19 switches the flow path 6 Coolant volume dependent on the first delivery line 17 or the second delivery line 18 ,

The switching device 19 This is also done by the control unit 11 driven. In the de-energized state, the switching device switches 19 on the first conveyor line 17 ,

The flow meter 9 is intended for an upper measuring range. As soon as the measured coolant quantity assumes too small measured values, the control unit switches 11 the switching device 19 around, so that the coolant is now through the second delivery line 18 the flow meter 10 is supplied. This flow meter 10 is more sensitive and set up for a lower measurement range and can measure the smaller readings more accurately. Conversely, a switchover from the second delivery line takes place 18 on the first conveyor line 17 instead, when the amount of coolant delivered increases above a threshold. So can the more sensitive flow meter 10 be protected against damage due to excessive flow rates and / or pressures.

Instead of the illustrated pump 2 can in the tool supply device according to the invention 1 also a pump 2 ' can be used, which is designed as a variable speed constant pump. The associated pump regulator 4 ' is designed according to known manner and is by the load pressure feedback 14 - depending on activation over the first branch 30 or the second pointer 31 - Controlled with the same controller behavior as previously described.

With a main valve 34 is the flow path 6 behind the flow control valve 7 , the flow meters 9 . 10 and the pressure sensor 12 lockable, for example, the tool 3 switch. With the main valve closed 34 The system can be biased or remain in a prestressed state, so that after the tool change, the filling phase must be very short or even completely eliminated.

2 shows a circuit diagram of another tool supply device according to the invention 1 , at 2 are constructive and / or functional details and components that are identical or similar to the embodiment according to 1 are configured, denoted by the same reference numerals and not described again separately. The remarks to 1 therefore apply to 2 corresponding.

The tool supply device 1 is to supply several tools 3 . 3 ' through the pump 2 set up. Exemplary shows 2 a first tool 3 and a second tool 3 ' , via respective flow paths 6 respectively 6 ' be supplied with coolant.

The supply of the tool 3 ' is in a similar way as the supply of the tool 3 designed. The statements therefore apply to the set reference numerals 3 ' . 6 ' . 7 ' etc. accordingly. In particular, thus has the flow path 6 ' also a flow control valve 7 ' with associated activation device 8th' and flow meter 9 ' . 10 ' with upstream switching device 19 ' on. The supply of the tool 3 ' is also controlled by the control unit 11 controlled.

In the tool supply device 1 according to 2 is a load pressure forming device 20 provided with which a maximum pressure from each of the flow paths 6 . 6 ' removed load pressures is formed.

This formed maximum pressure is then passed over the second branch 31 the load pressure feedback 14 to the pump regulator 4 recycled.

By a cascading of such load pressure forming devices 20 In this way, any number of tools can be integrated into the supply shown.

With deactivated switching device 13 becomes the primary pressure from the outlet 5 the pump 2 to the pump regulator 4 recycled.

3 shows a circuit diagram of another tool supply device according to the invention 1 , In the embodiment according to 3 are again components and details that correspond to the embodiments according to 1 and or 2 are functionally or constructively identical or identical, designated by the same reference numerals and not described again separately. The remarks to the 1 and 2 therefore apply to 3 corresponding.

The embodiment according to 3 is different from the previous ones Embodiments characterized in that the pump 2 ' not just the flow paths 6 . 6 ' , but also a coolant reservoir 21 provided. Thus, the coolant delivery in the current paths 6 . 6 ' on the operation of the pump 2 ' be decoupled.

Here is the operating pressure 22 to the pump 2 ' recycled to regulate the operating pressure.

For this purpose, the operating pressure 22 to a pressure sensor 23 detects which the pump controller 4 ' controls accordingly.

In 3 it can be seen that the load pressure feedback 14 not to the pump regulator 4 ' but to a pressure balance 24 is returned, which the flow control valve 7 upstream.

In this way is also achievable that with activated switching device 13 a desired pressure behind the flow control valve 7 is adjustable without putting in the pump regulator 4 must be intervened. With deactivated switching device 13 is such a desired pressure in front of the flow control valve 7 adjustable.

5 shows an alternative to 1 , which also in the embodiments according to 2 or 3 can be used. In the embodiment according to 5 are again components and details that are functionally or constructively identical or identical to the preceding embodiments, designated by the same reference numerals and not described again separately. The remarks to the 1 to 3 therefore apply to 5 corresponding.

The embodiment according to 5 differs from the previous embodiments in that instead of the first flow meter 9 respectively. 9 ' a pressure control valve 35 is provided. About the pressure control valve 35 a filling pressure (as working pressure) is set in the filling phase I. The pressure control valve 35 can thus also the pressure presetting valve 29 respectively. 29 ' and / or the pressure balance 24 respectively. 24 ' replace, especially in 3 , It is thus dispensed with a monitoring of the amount of coolant at large amounts of coolant, and the pressure control valve 35 On the output side, sets a desired pressure. This is sufficient for many applications. When falling below the mentioned threshold value for the operating coolant quantity switches the switching device 19 on the second delivery line 18 , and the flow meter 10 is used for the now flowing small amounts of coolant. The flow meter 10 is used in the described manner for tracking the opening cross-section 36 used.

4 shows in a very simplified schematic representation of the sequence of a method according to the invention. The following statements apply to the presented embodiments according to 1 to 3 respectively.

Shown is the time sequence, where the time scale is plotted on the X-axis and the value scale belonging to the individual curves is plotted on the Y-axis.

It is the time course of the primary pressure p _V1 at the output 5 the pump 2 , the working pressure p _is at the tool 3 , measured by the pressure sensor 12 , the amount of coolant Q _is on the tool 3 , measured with the flow meter 9 respectively 10 , the setting "SRV" of the opening cross section 36 at the flow control valve 7 and the setting "V3" of the switching device 13 , Here, a low level value according to the starting position 1 and a high level value indicates the switched position.

In a filling phase designated I, first the flow control valve 7 fully open, and there is a constant primary pressure p _V1 at the output 5 set. There is thus a pressure-controlled delivery of coolant instead.

Since the filling process I is performed at the beginning of operation or after a tool change, the supply lines 25 . 25 ' to the tools 3 . 3 ' unfilled.

Accordingly, the applied primary pressure in the filling phase I causes a large amount of refrigerant to be rapidly delivered. Accordingly, the amount of coolant increases at the flow meter 9 respectively 10 at.

This is where the pump becomes 2 operated at a constant primary pressure.

When the supply lines 25 . 25 ' filled, the working pressure on the tool increases 3 . 3 ' at. After exceeding a work threshold 26 through this working pressure on the tool 3 . 3 ' recognizes the control unit 11 in that the filling phase is completed.

After a learning and / or testing phase II, which is explained below, the operational phase III follows. In this operating phase III, the flow control valve 7 activated to the at least one tool 3 . 3 ' to promote a constant operating coolant quantity.

While the flow control valve 7 . 7 ' in the filling phase I was fully opened, the opening cross-section 36 of the flow control valve 7 in the Operating phase III, on the other hand, reduced. With the pressure balance 37 of the flow control valve 7 . 7 ' will be a pressure drop across the opening cross-section 36 so regulated, that at the tool 3 . 3 ' gives the desired amount of operating coolant per unit time. There is thus a quantity-controlled promotion instead.

In the learning and / or testing phase II, the primary pressure p _{V1 is} pressure-regulated as a function of the working pressure p _ist . For this purpose, the primary pressure p _V1 over the first branch 30 the load pressure feedback 14 to the pump regulator 4 recycled. By way of example, it is shown in the middle of the learning and / or testing phase II that the set primary pressure p _{V1 is} lowered in one stage because the working pressure p _{ist is} too high.

After a transient phase, the working pressure p _{ist is set} to the primary pressure p _V1 . Corresponding to this arises after a transient phase, the coolant quantity Q _is on the tool 3 . 3 ' also to a constant value.

In the control unit 11 is a monitoring device 27 trained, with which is automatically recognizable when the amount of coolant at the flow meter 9 . 10 and / or the working pressure at the pressure sensor 12 occupy / take stationary values. Instead of the monitoring device 27 In other embodiments, it is also possible to wait for a period of time after which, according to experience, the stationary values are established.

The prevailing upon reaching this steady state value for the amount of coolant is used as the operating coolant amount 28 to the tool 3 . 3 ' deposited. If an operating coolant quantity has already been stored, the newly obtained value is compared with the stored value and an error is issued if the deviation is too great. In the embodiments according to 2 and 3 Each tool is a separate flow meter 9 . 9 ' respectively. 10 . 10 ' assigned. It can therefore be any tool 3 . 3 ' a separate operating coolant quantity 28 be assigned.

Once the steady state is detected and the operating coolant quantity 28 is deposited, the learning and / or testing phase II is completed and the already mentioned operating phase III is automatically opened.

For this purpose, the previously fully open flow control valve 7 to a desired opening cross-section 36 closed, and it comes with the flow control valve 7 a flow control function activated. Thus, quantity-based promotion begins.

The flow control valve 7 In this case, it is closed so far until the amount of coolant rises again and / or until the working pressure p _is broken.

At the beginning of the operating phase, the primary pressure p _V1 is first increased by one stage in the initial phase IIIa. This level is equal to the pressure difference across the flow control valve 7 , The pressure increase is here at the control point 16 added to the load pressure feedback. Following is the already mentioned second branch 31 the load pressure feedback 14 activated. This is indicated by an increase in the level of "V3", which is a switching of the switching device 13 displays. The load pressure feedback 14 is thus a tapping point 32 in front of the flow control valve 7 on a tap point 33 behind the flow control valve 7 switched. Thus, now is a desired pressure at the output 15 of the flow control valve 7 adjustable.

Finally, at the beginning of the working phase IIIb, the primary pressure is again increased by a further step and then kept constant.

In 4 It can be seen that the primary pressure in the operating phase III compared to the filling phase I has a higher value. This takes into account the fact that in the operating phase III with activated flow control valve 7 an additional pressure difference drops.

In the filling phase I, the primary pressure p _{V1 was} via the pressure presetting valve 29 set to the tool-specific predetermined value.

Become tools 3 . 3 ' with very tight supply lines 25 . 25 ' used, it may happen that in the learning and / or testing II a very low value for the operating coolant amount 28 adjusts or even no stationary state and thus no constant amount of coolant is achieved.

In this case, breaks the control unit 11 the monitoring of whether a stationary state was achieved with constant values for the coolant quantity and / or the working pressure, after a predetermined period of time and continues the control method of the learning and / or test phase II indefinitely as normal operation. In this case, the flow control valve remains 7 thus deactivated, and there is a small amount promotion pressure-controlled instead.

Become tools 3 . 3 ' with very wide open supply lines 25 . 25 ' used, it may happen that the said working threshold in the filling phase I is not reached.

In this case, breaks the control unit 11 the monitoring of whether the working threshold (of below) has been reached or exceeded after a predetermined period of time and continues the control procedure of the operating phase III indefinitely as normal operation. In this case, a preset value is used as the operating refrigerant amount, and large-volume production is quantity-controlled.

In the operating phase III, a tool break can be detected by the fact that the working pressure at the pressure sensor 12 abruptly decreases.

Because the tool breakage causes the flow resistance of the tool 3 . 3 ' suddenly reduced.

The load pressure feedback 14 picks up this pressure drop and gives it to the pump regulator 4 further.

As a result, the pump controller regulates 4 to a smaller amount of coolant provided. Thus, it can be prevented that an excessive amount of coolant is conveyed.

Conversely, the control unit recognizes 11 a blockage of the supply line 25 . 25 ' of the tool 3 . 3 ' Remember that the working pressure at the pressure sensor 12 rises abruptly.

Here leads the load pressure feedback 14 . 14 ' to that from the pump 2 subsidized coolant quantity is reduced. Thus, an excessive pressure increase is caused by the fact that the pump 2 against the blockage of the supply line 25 works, avoided.

In the tool supply device 1 with a p / Q-controlled pump 2 for supplying at least one tool 3 . 3 ' with coolant is proposed, in an operating phase III, a flow control valve 7 . 7 ' in a the at least one tool 3 . 3 ' supplying flow path 6 . 6 ' to activate to at least one tool 3 . 3 ' to promote a constant amount of operating coolant volume controlled, the operating phase III a filling phase I, in which a supply line 25 . 25 ' of the tool 3 . 3 ' pressure-controlled is filled, and / or a learning and / or test phase II, in which the operating coolant amount of the operating phase III is pressure-controlled determined and / or checked, is / are upstream.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102011013151 A1 [0003]
• DE 102006052602 A1 [0003]

Claims (16)

Method for supplying coolant to at least one tool ( 3 . 3 ' ), wherein the at least one tool ( 3 . 3 ' ) with a coolant supply device ( 1 ) via a p / Q-controlled pump ( 2 . 2 ' ) is supplied with coolant, wherein the pump ( 2 . 2 ' ) provides a primary pressure (p _V1 ) on the output side and on the at least one tool ( 3 . 3 ' ) produces a working pressure (p _ist ), characterized in that in a filling phase (I) the coolant supply device ( 1 ) is operated under pressure control until the working pressure (p _is ) at the at least one tool ( 3 . 3 ' ) a work threshold ( 26 ), and that after completion of the filling phase (I) in an operating phase (III), one of the pumps ( 2 . 2 ' ) downstream flow control valve ( 7 . 7 ' ) is activated to be connected to the at least one tool ( 3 . 3 ' ) a constant amount of operating coolant ( 28 ) to promote. A method according to claim 1, characterized in that the filling phase (I) with a filling operation of an at least partially empty supply line ( 25 . 25 ' ) to the at least one tool ( 3 . 3 ' ) starts and / or that the pump ( 2 . 2 ' ) in the filling phase ( 5 ) is operated under pressure control with a constant primary pressure (p _V1 ). Method according to claim 1 or 2, characterized in that the flow control valve ( 7 . 7 ' ) in the filling phase (I) is preferably fully opened and / or deactivated and / or that at the flow control valve ( 7 . 7 ' ) in the operating phase (III) compared to the filling phase (I) a reduced opening cross-section ( 36 ) is set. Method according to one of claims 1 to 3, characterized in that in the operating phase (III) a load pressure feedback ( 14 . 14 ' ) to the pump ( 2 . 2 ' ) from a tapping point ( 32 ) in front of the flow control valve ( 7 ) to a tapping point ( 33 ) behind the flow control valve ( 7 ) is switched, in particular wherein the load pressure feedback ( 14 . 14 ' ) after switching a pressure drop across the flow control valve ( 7 ) corresponding pressure difference is added and / or wherein in the load pressure feedback ( 14 . 14 ' ) a maximum pressure from at least two tools ( 3 . 3 ' ) applied working pressures (p _is ) and / or behind at least two flow control valves ( 7 . 7 ' ) applied load pressures is formed. Method according to one of claims 1 to 4, characterized in that the primary pressure (p _V1 ) in the operating phase (III) relative to the filling phase (I) is raised and / or that at the beginning of the operating phase (I), in particular after the activation of Flow control valve ( 7 . 7 ' ), in a connection phase (IIIa) first the primary pressure (p _V1 ) is increased by one stage and then the or a load pressure feedback (IIIa) 14 . 14 ' ) to the pump ( 2 . 2 ' ) is activated. Method for supplying coolant to at least one tool ( 3 . 3 ' ), in particular according to one of claims 1 to 5, wherein the at least one tool ( 3 . 3 ' ) with a coolant supply device ( 1 ) via a p / Q-controlled pump ( 2 . 2 ' ) is supplied with coolant, the pump on the output side provides a primary pressure (p _v1 ) and on the at least one tool ( 3 . 3 ' ) generates a working pressure (p _ist ), characterized in that in a learning and / or testing phase (II), the at least one tool ( 3 . 3 ' ) associated operating coolant quantity ( 28 ) is determined and / or tested and that after completion of the learning and / or testing phase (II) in an operating phase (III), one of the pumps ( 2 . 2 ' ) downstream flow control valve ( 7 . 7 ' ) is activated to be connected to the at least one tool ( 3 . 3 ' ) the operating coolant quantity ( 28 ) to promote constant time. A method according to claim 6, characterized in that in the learning and / or test phase (II) the pump ( 2 . 2 ' ) Pressure-regulated in dependence of the working pressure _(p) is operated and / or that (in the learning and test phase II) of the primary pressure (p _V1) is regulated such that the primary pressure (p _V1) and the working pressure _(p) have a predetermined pressure difference. Method according to claim 6 or 7, characterized in that the operating coolant quantity ( 28 ) is measured or checked in the learning and / or testing phase (II) if one of the at least one tool ( 3 . 3 ' ) Supported coolant quantity _(Q) and / or the working pressure _(p) assumes constant values / assume and / or that a control behavior of the learning and / or test phase (II) in the operating phase (III) is continued unchanged if the Operating coolant quantity ( 28 ) is below a predetermined value. Method according to one of claims 1 to 8, characterized in that of the filling phase (I) is changed directly into the operating phase (III), if after a predetermined period of time the working threshold is not reached, wherein in the operating phase (III) a predetermined maximum amount as operating coolant quantity ( 28 ), and / or that a first delivery line ( 17 . 17 ' ) to the at least one tool ( 3 . 3 ' ) is used when the at least one tool ( 3 . 3 ' ) associated operating coolant quantity ( 28 ) is above a threshold, and that automatically to a second delivery line ( 18 . 18 ' ) to the at least one tool ( 3 . 3 ' ) is changed when the operating coolant quantity ( 28 ) falls below the threshold value, whereby in the first delivery line ( 17 . 17 ' ) a flow meter ( 9 . 9 ' ) for an upper one Measuring range or a pressure regulating valve ( 35 ) and in the second funding line ( 18 . 18 ' ) a flow meter ( 10 . 10 ' ) is arranged for a lower measuring range. Method according to one of claims 1 to 9, characterized in that with the pump ( 2 . 2 ' ) a coolant reservoir ( 21 ), wherein an operating pressure ( 22 ) of the coolant reservoir ( 21 ) to the pump ( 2 . 2 ' ) and / or that the or a load pressure feedback ( 14 . 14 ' ) of the pump ( 2 . 2 ' ) or a flow control valve ( 7 . 7 ' ) upstream pressure balance ( 24 . 24 ' ) is supplied. Tool supply device ( 1 ) with a p / Q-controlled pump ( 2 . 2 ' ) for supplying at least one tool ( 3 . 3 ' ) with coolant, characterized in that a flow control valve ( 7 . 7 ' ) of the pump ( 2 . 2 ' ) is downstream, that the flow control valve ( 7 . 7 ' ) deactivatable to provide a constant pressure on the at least one tool ( 3 . 3 ' ) and activatable to provide a constant amount of operating coolant ( 28 ) on the at least one tool ( 3 . 3 ' ) and that an activation device ( 8th . 8th' ) for activating the flow control valve ( 7 . 7 ' ), when a working pressure (p _is ) on the at least one tool ( 3 . 3 ' ) a work threshold ( 26 ) is reached or exceeded. Tool supply device ( 1 ) according to claim 11, characterized in that the flow control valve ( 7 . 7 ' ) a flow meter ( 9 . 9 ' . 10 . 10 ' ), in particular wherein a control connection between the flow meter ( 9 . 9 ' . 10 . 10 ' ) and the flow control valve ( 7 . 7 ' ) is designed to provide a constant amount of operating coolant ( 28 ) on the at least one tool ( 3 . 3 ' ), and / or that a regulatory unit ( 11 ) for deactivatable control of one of the pump ( 2 . 2 ' ) is provided on the output side provided primary pressure (p _v1 ) on or in dependence on the working pressure (p _ist ). Tool supply device ( 1 ) according to claim 11 or 12, characterized in that a switching device ( 13 . 13 ' ) is present, with which a load pressure feedback ( 14 . 14 ' ) from a tapping point ( 32 ) in front of the flow control valve ( 7 ) to a tapping point ( 33 ) behind the flow control valve ( 7 ) is switchable, in particular wherein the load pressure feedback ( 14 . 14 ' ) after switching to the tapping point ( 33 ) with a pressure drop across the flow control valve ( 7 ) is acted upon additively corresponding pressure difference and / or a load pressure forming device ( 20 ) for forming a recirculated load pressure as maximum pressure from at least two tools ( 3 . 3 ' ) applied working pressures and / or behind at least two flow control valves ( 7 . 7 ' ) applied load pressures is established. Tool supply device ( 1 ) according to one of claims 11 to 13, characterized in that a first delivery line ( 17 . 17 ' ) and a second funding line ( 18 . 18 ' ) to the at least one tool ( 3 . 3 ' ), wherein a switching device ( 19 . 19 ' ) to a switching from the first delivery line ( 17 . 17 ' ) to the second pipeline ( 18 . 18 ' ), if a subsidized operating coolant quantity ( 28 ) is below a threshold, is set up and wherein in the first delivery line ( 17 . 17 ' ) a flow meter ( 9 . 9 ' ) with an upper measuring range or a pressure regulating valve ( 35 ) and in the second funding line ( 18 . 18 ' ) a second flow meter ( 10 . 10 ' ) is arranged with a lower measuring range. Tool supply device according to one of claims 11 to 14, characterized in that the pump ( 2 . 2 ' ) to a coolant reservoir ( 21 ), wherein an operating pressure ( 22 ) of the coolant reservoir ( 21 ) to the pump ( 2 . 2 ' ) and / or that monitoring means ( 27 ) for detecting a time constant value of a conveyed coolant quantity (Q _ist ) at the at least one tool ( 3 . 3 ' ) and / or the working pressure (p _ist ) are established. Tool supply device ( 1 ) according to one of claims 11 to 15, characterized in that the control unit ( 11 ) for selectively conveying after at least two control and / or regulating behavior from the group of pressure-controlled, pressure-controlled and volume-controlled conveying of coolant to the at least one tool ( 3 . 3 ' ) and / or that means for carrying out a method according to one of claims 1 to 10 are formed.

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