Fixture for de-icing and hardening a workpiece with specifically controllable channels for supplying de-icing medium

Description

[0001] The invention relates to a fixture and a method for quenching workpieces as part of a hardening process. The fixture has a holder and a mandrel that engages centrally in an annular workpiece. Generic fixtures can also have hold-down devices to secure the workpiece to prevent it from warping during cooling, or, if it has already warped during heating, to press it back into shape. Gases and liquids can be used as quenching media, although due to the high temperatures on the workpiece, liquid quenching agents partially evaporate, at least at the beginning of the quenching process.

[0002] A method and device for hardening workpieces using press tools is known from DE 40 04 295 C2. This proposes measuring the effects of the specified process parameters directly or indirectly during each quenching process and automatically adjusting the specified process parameters in the event of deviations from the desired target, based on the known effects of the process parameters. A flow rate of circulating coolant can be adjusted for the entire fixture within certain limits according to a required setpoint.

[0003] DE 10 2009 004 125 A1 relates to a pressurized fixing device for workpieces to be thermally treated, which device integrates a support device on which at least one workpiece to be thermally treated rests during operation during a hardening or cooling process, wherein the support device provides support positions in only one horizontal plane, and a hold-down device arranged above the support positions, which has a plurality of hold-down tools that provide hold-down ends directed towards the support positions, wherein the hold-down tools are each individually arranged to be vertically movable and can be pressurized in such a way that in a loading or unloading state of the device, a free space is defined between each hold-down end and the support positions, which is completely closed during operation during a hardening and / or cooling process, in such a way thatthat each hold-down end rests either on a support position or on a workpiece to be thermally treated.

[0004] EP 2 700 725 A2 discloses a method for hardening an individual, annular workpiece and a fixture designed for this purpose, in which a single, annular workpiece to be hardened is placed with its opening over a mandrel until the workpiece rests with a first end face on a support; one or more hold-down devices are fed from a side facing opposite the first end face towards the support until the hold-down device(s) rests with force on a second end face of the workpiece facing opposite the first end face; cold, gaseous quenching agent is fed at least to surfaces of the workpiece that border the workpiece and are facing opposite one another; and heated quenching agent is removed. Gaseous and liquid quenching agents can be fed to the workpiece separately.

[0005] At least one temperature sensor is arranged within the fixture to measure the temperature of the workpiece. The temperature sensor is connected to a control and / or regulating device for adjusting the supply of quenching agent based on the temperature of the workpiece. The amount of gaseous and liquid quenching agent can be controlled globally for the entire fixture or the entire workpiece.

[0006] In the article "Fixture Hardening of Large Components" from September 5, 2016, published under Industrial Heating by Gerd Müller-Laessing and Markus Ströbl, it is demonstrated that it is possible to straighten distorted ring-shaped workpieces, especially gears, or restore their roundness through a quenching process. To achieve this, the workpieces are subjected to radial force from the inside during quenching and compressed axially by hold-down clamps. The amount of quenching agent is set high enough to ensure uniform cooling. The distribution of quenching agent from the inside to the outside can be adjusted to an optimal rate for each workpiece.

[0007] Anders Olofson's dissertation Hardening Distortions of Serial Produced Gears, KTH Royal Institute of Technology, Stockholm, 2017, ISBN 978-91-7729-449-8, comprehensively investigates which parameters lead to deformations in the gear manufacturing process, from primary forming to quenching.

[0008] CN 108 486 334 A already discloses a die-press quenching device for components, particularly gear rims. This device allows the upper and lower end surfaces of the gear rim to be firmly pressed by the upper die seat and the lower template, thus limiting deformation of the end surfaces of the gear rim. The outer circumference of the gear rim is firmly pressed by the wedge block mounted on the upper tool seat, limiting deformation of the outer circumference of the gear rim. This prevents the central part of the gear rim from clumping during quenching, thereby improving the quenching efficiency and quality of the workpieces to be treated.

[0009] WO 99 027 44 A1 describes a method for carrying out a heat treatment on steel rings, in particular for bearings, in which the outer surface and the inner surface of a preheated ring are exposed to different flows of a cooling medium so that the areas of these surfaces are subjected to different cooling processes, and the current supply is controlled in such a way that a desired residual stress pattern is obtained in the ring by controlling the propagation of a phase transformation from austenite to martensite material structure.This allows the shape of the rings to be controlled in a more reliable manner by applying a cooling medium consisting of a combination of liquid and gas and clamping the ring in the axial direction in its inner diameters, wherein the clamping force is controlled in such a way that out-of-roundness due to the cooling processes is kept to a minimum, and wherein the clamping force exerted in the axial direction is controlled in relation to the temperature decrease of the ring below the martensite transition temperature.

[0010] JP H07 268 482 A discloses the provision of a hardening method for a gear element capable of uniformly cooling the entire surface of the teeth of this gear element and the device therefor.

[0011] WO 2017 077 376 A1 describes a system for cooling an extruded product at the outlet of an extruder, wherein a support surface is adapted to receive an extruded product from the extruder and wherein dispensing means are provided which are suitable for directing a cooling fluid onto the extruded product.

[0012] One object underlying the invention is to improve the controllability of the quenching process. This object is achieved by a device and a method according to the features of the independent claims. The subclaims can be combined with one another in a technologically expedient manner and they reveal further aspects of the invention.

[0013] The description, particularly in conjunction with the figures, further specifies and characterizes the invention. Accordingly, a fixture for quenching workpieces is provided, comprising a closable receptacle for a workpiece and a plurality of fluid-conducting channels for supplying quenching medium into the receptacle and thereby to the workpiece. Volume flows of quenching medium to groups of channels can be regulated in order to specifically influence the cooling rate on the workpiece during a quenching process.

[0014] The ability to regulate groups of channels allows for targeted response to uneven cooling rates on the workpiece. Quenching medium no longer needs to be increased globally for the entire fixture simply because the flow rate is insufficient at a single location. This significantly improves process control during quenching because flow rates at groups of channels can be reduced in favor of hotter spots on the workpiece with higher demand.

[0015] In other words, the distribution of volume flows around the workpiece can be adjusted to a uniform cooling rate. This prevents deformations caused by uneven cooling. Furthermore, a very specific cooling rate can be maintained locally at almost any point on the workpiece to which a channel is directed, in order to achieve defined material properties. The holder can have a base, side walls, a cover, and a mandrel penetrating the center of the workpiece. The fluid-conducting channels open into the holder and, if possible, are aligned so that the quenching medium emerging from them is directed onto the workpiece. The channels are essentially round holes arranged next to one another in a circle. Liquids and gases can be used as the quenching medium.

[0016] In one embodiment, ring-shaped groups of channels are provided for an annular workpiece with a radially outer outer side, a radially inner inner side, an axially upper upper side and an axially lower lower side, wherein a first group is arranged in the receptacle such that the channels assigned to it flow onto the outer side from an axial direction, a second group is arranged such that the channels assigned to it flow onto the outer side in a planar manner from the underside to the upper side, a third group is arranged such that the channels assigned to it flow onto the underside, a fourth group is arranged such that the channels assigned to it flow onto the inner side in a planar manner from the underside to the upper side, a fifth group is arranged such that the channels assigned to it flow onto the inner side radially outwards and a sixth group is arranged such thatthat the channels assigned to it flow to the top.,

[0017] This makes it possible to achieve uniform cooling on every outer surface of a ring-shaped workpiece, especially a gear.

[0018] In one embodiment, the volume flow is regulated via valves which are fluidically connected to the channels on the output side and to at least one supply chamber pressurized with quenching medium on the input side.

[0019] The groups of channels can each be controlled by a valve or each channel in a group can be controlled by its own valve.

[0020] In one embodiment, the valves are proportional valves which have a variable flow behavior depending on an input signal.

[0021] By using proportional valves, the volume flow into the ducts can be continuously adjusted to precisely meet existing requirements.

[0022] In one embodiment, volume flow sensors are provided in the channels, in particular close to the workpiece, which are designed to detect a volume flow directed to the channels and to generate a signal.

[0023] In a further embodiment, temperature sensors are arranged in the fixture, in particular close to the workpiece, which are designed to detect a temperature radiated by the workpiece and to generate a signal.

[0024] The temperature sensors can be arranged in such a way that they detect a temperature radiated by the workpiece close to a channel that irradiates the workpiece. In this context, irradiation means the directed application of quenching medium. In other words, the temperature sensors are preferably located in the fixture or holder in such a way that a hot position on the workpiece detected by them can be directly exposed to the quenching medium. In the current state of the art, empirically determined data is recorded individually for each workpiece and the quenching medium is supplied to each workpiece accordingly, without precise knowledge of the processes in the fixture. By using monitoring in the form of temperature sensors, it is possible to immediately detect higher localized requirements for quenching medium and to increase the volume flow there accordingly so that a targeted cooling rate can be maintained.

[0025] In one embodiment, sound sensors are arranged in the fixture, particularly close to the workpiece.

[0026] The sound sensors provide the control unit with additional data that provides information about the cooling behavior. Direct feedback in the form of sound waves from the workpiece itself is provided, especially in the event of (unwanted) cracking or splitting on the workpiece surface due to excessive surface and residual stresses. Sound sensors indirectly provide information about the surface temperature, since the quenching medium evaporates faster and louder the higher the surface temperature of the workpiece.

[0027] In one design, the volume flow sensors are integrated into the valves.

[0028] This allows for a compact fixture design. In a further embodiment, the valves are formed by an upper valve plate and a lower valve plate, which is arranged so as to be movable relative to the upper valve plate in order to overlap holes in the lower valve plate with holes in the upper valve plate.

[0029] The valve plates can, in particular, be rotated relative to one another to release different channels or groups of channels with increasing rotation, or to provide a fluid-conducting connection from supply chambers to the group of channels. In one embodiment, the valves and sensors are coupled to a control device for signal transmission. The control device is designed to process the signals detected by the sensors and generate actual values ​​therefrom. In the event of a deviation of an actual value from a setpoint, the valves are controlled in a differentiated manner to achieve a definable, controllable local volume flow.

[0030] In a further embodiment, a digital model of the fixture is implemented in a control device, which is used in the control device to anticipate a temperature distribution close to the workpiece and to output correction values ​​for the regulation of the volume flows in the respective groups of channels.

[0031] By precisely knowing the current state (temperature distribution and flow rates) of the fixture and comparing it with a digital model, a computer-implemented response to a shift in a control setpoint can be predicted, and the valves or valve plates can be controlled accordingly to achieve a desired temperature distribution and a desired distribution of quench medium flow rates. The precision of a control setpoint change and the subsequent response of the fixture can thus be increased compared to a control system that relies solely on feedback from sensors to adjust for a deviation between a setpoint and an actual value.

[0032] In a further embodiment, a digital model of the workpiece is implemented in a control device, which model anticipates a flow distribution and a resulting temperature distribution on the workpiece in the control device based on a position and a direction of the channels and outputs correction values ​​for the regulation of the volume flows in the respective channels.

[0033] By precisely knowing the current state of the workpiece, particularly the temperature distribution, and the conversion, heat transfer, and diffusion processes in a digital model, the workpiece's reaction to a shift in the fixture's control setpoint can be predicted or, even more precisely, computer-implemented. The valves or valve plates can be controlled accordingly to achieve a desired cooling rate. The precision of a control setpoint change and the subsequent chemical-physical reaction of the workpiece can thus be increased. A further advantage is that the fixture can be adapted for different workpieces by simply implementing a digital model corresponding to the workpiece to be quenched. The fixture or control system then automatically assumes ideal process control.According to the invention, means are provided which can be stored in a control unit for regulating a fixture in order to cool a workpiece which can be placed in a holder, comprising: . i. Means for detecting a locally increased or reduced cooling rate requirement on a workpiece placed in a holder of the fixture, ii. Means for establishing a control setpoint for control elements for controlling a volume flow in the fixture, iii. Means for controlling the volume flows of quenching medium in channels ending in the holder, each individually or bundled in groups, in order to specifically influence the cooling rate on the workpiece locally during a quenching process according to the increased or reduced requirement.

[0034] Control devices can be adjustable pumps or valves that distribute a pressurized quenching medium to the channels and are designed to adjust the flow rate. This can be done using PWM-controlled switching valves and / or proportional valves.

[0035] These resources can be further developed through: i. Means for detecting an actual temperature and a cooling rate by at least one, preferably several temperature sensors arranged close to the workpiece, and assigning them to a currently available control actual value for control elements for controlling the volume flows, ii. Means for detecting an ideal temperature and a cooling rate, which ideally should be present on the workpiece in order to achieve predefined material properties, using a digital model of the workpiece or the fixture holder stored in a control device, iii. Means for creating the control setpoint according to point ii. of claim 13 based on a difference between the actual temperature and the ideal temperature.

[0036] In a further development, the following are also provided: i. Means for detecting a noise level in the fixture using a sound sensor; ii. Means for detecting a pressure difference before and after the workpiece in the fixture using a plurality of pressure sensors; iii. Means for supplementing an actual state of the real workpiece based on the pressure difference and the noise level.

[0037] A means within the meaning of the present invention can be embodied in hardware and / or software. In particular, a means can comprise a processing unit, in particular a control unit with microprocessors (CPU), which is connected to a memory and / or bus system in terms of data or signals, and / or a control unit with microprocessors (CPU), and / or one or more programs or program modules. The CPU can be designed to process instructions implemented as a program stored in a memory system, to detect input signals from a data bus, and / or to output output signals to a data bus. A memory system can comprise one or more, in particular different, storage media, in particular optical, magnetic, solid-state, and / or other non-volatile media. The program can be designed in such a way that it embodies the methods described here orcapable of executing such a method, so that the CPU can execute the steps of such methods and thus, in particular, can control, in particular regulate, the fixture. In one embodiment, one or more, in particular all, steps of the method can be carried out fully or partially automatically, in particular by the controller or its means. Short description of the characters

[0038] The drawings described herein are for illustrative purposes only and are not intended to limit the scope of the present disclosure in any way. They show: Fig. 1 : in section a part of a fixture with a holder, which more or less positively holds a workpiece and clamps it with a central mandrel radially from the inside and axially via hold-down devices, and Fig. 2 : a view of the fixture, Fig. 3 : schematically three process steps that can take place in the fixture to control the fixture, and Fig. 4: a part of two in a fixture according to Figure 1 or Figure 2 insertable valve plates. Detailed description of the characters

[0039] The following description is merely illustrative in nature. For clarity, the same reference numerals are used throughout the drawings to identify similar elements. It should be noted that steps within a method may be performed in a different order without altering the principles of the present disclosure. Steps of the method may include multiplications, summations, and selections, as well as assignments, for example, assignment of output values ​​to input values ​​in characteristic maps.

[0040] Figure 1shows a fixture 1 for quenching workpieces 2 with a closable holder 3 for the workpiece 2 and a plurality of fluid-conducting channels 4 which open into the holder 3, for supplying quenching medium into the holder 3 and thereby to the workpiece 2. The channels 4 are predominantly directed towards the workpiece 2, i.e. quenching medium emerging from the channels 4 directly impacts surfaces on the workpiece 2. The holder 3 has a mandrel 5 in its center which can be guided through the annular workpiece 2. The workpiece 2 is a gear with two gear rings. A hold-down device 6 holds the workpiece 2 in position in the axial direction A.

[0041] The fixture has six groups of channels 4. Each group of channels 4 opens directly or after being redirected into the holder 3. The channels 4 are arranged concentrically next to one another in a ring around the workpiece 2. The channels 4 open into the holder 3 in such a way that the quenching medium flowing through them is evenly distributed over the workpiece 2.

[0042] A first group G1 is arranged in the holder 3 in such a way that the channels 4 assigned to it flow against an outer side 7 of the workpiece 2 from the outside in a direction opposite to a radial direction R. The air flowing against the outer side 7 and in Figure 1The channels 4 shown are part of a large number of channels 4 assigned to group G1 and arranged in a ring around the workpiece 2; for the sake of simplicity, only four channels 4 are shown. A second group G2 is arranged such that the channels 4 assigned to it flow across the outer side 7 from a bottom side 8 to a top side 9. Two channels 4 of the second group G2 are visible, but the channels 4 of group G2 are arranged next to one another concentrically to the axial direction A around the entire circumference. A third group G3 is arranged such that the channels 4 assigned to it flow across the bottom side 8. Again, only two channels 4 of the third group G3 are visible, but the channels 4 of group G3 are also arranged next to one another concentrically to the axial direction A around the entire circumference. A fourth group G4 is arranged such that the channels 4 assigned to it flow across an inner side 10 of the workpiece 2 from the bottom side 8 to the top side 9.Visible in . Figure 1 again only two channels 4 of the fourth group G4. However, the channels 4 of the fourth group G4 are also arranged concentrically to the axial direction A around the entire circumference. A fifth group G5 is arranged so that the channels 4 assigned to it flow outwards towards the inner side 10 from the inside of the mandrel 5 in the radial direction R. Shown in Figure 1 again only two channels 4 of the fifth group G5. However, the channels 4 of the group G5 are also arranged concentrically to the axial direction A around the entire circumference next to each other. A sixth group G6 is arranged so that the channels 4 assigned to it flow towards the upper side 9. The same applies to the sixth group G6 that the channels assigned to it are arranged concentrically to the axial direction A around the entire circumference next to each other, but only two in Figure 1 can be seen. Channels 4 of the sixth group G6 are supplied with quenching medium from mandrel 5.

[0043] Controllable volume flows Q1, Q2, Q3, Q4, Q5, and Q6 of quenching medium enter the receptacle 3 through groups G1 to specifically influence the cooling rate on the workpiece 2 during a quenching process. The volume flows Q1 to Q6 can be adjusted via valves 11, with only one valve 11 being shown schematically as an example. Valve 11 is controllable; in particular, it is a proportional valve. Other designs, such as switching valves controlled by PWM (pulse width modulation), are also conceivable.

[0044] In Figure 2two supply chambers 12 and 13 are shown which, during operation, are flooded with quenching medium which is under a certain pressure. The valves 11 are designed to establish a fluid-conducting connection between the supply chambers 12, 13 and the groups G1 to G6 of channels 4 and to regulate this continuously within certain limits. These certain limits arise from a design-related throttling effect of the valves 11. The valves 11 are therefore selected such that a volume flow Q1 to Q6 required for a desired cooling rate can be achieved. The second supply chamber 13 is arranged concentrically within the second supply chamber 12. The first supply chamber 12 supplies the groups G1 to G2 with quenching medium when the valves 11 assigned to them are open. The second supply chamber 13 supplies the groups G3 to G6 with quenching medium when the valves 11 assigned to them are open.

[0045] Furthermore, volume flow sensors 14 are provided in the channels 4 and the valves 11, respectively. These sensors are designed to detect a volume flow Q1 to Q6 directed to the channels 4 and generate an electrical analog or digital signal. The signal can be detected and processed by a control device 15. The signal corresponding to the respective volume flow Q1 to Q6 can be transmitted wirelessly via a cable (not shown).

[0046] Furthermore, temperature sensors TC3, TC4, TC5, TC6 are arranged in the fixture, particularly close to the workpiece 2. These sensors are designed to detect a temperature radiated by the workpiece 2 and generate an analog or digital signal. The signal can be detected and processed by the control device 15. The signal corresponding to the respective temperature can be transmitted wirelessly via a cable (not shown). Temperature-insensitive and fast-reacting temperature sensors TC3 to TC6 are preferably used.

[0047] Furthermore, Figure 2A first temperature sensor TC1 is shown, which is arranged in the first supply chamber 12 to detect the temperature of the quenching medium in the first supply chamber 12. A seventh temperature sensor TC7 is arranged at an outlet 16 for discharging quenching medium from the fixture 1. The quenching medium can then be processed in a manner not shown, in particular cooled, filtered if necessary, and mixed with fresh quenching agent if necessary, and then fed back to the supply chambers 12 and 13.

[0048] Temperature sensors TC1 to TC7 have already been introduced to monitor the quenching process. The fixture 1 also has sound sensors S1, which can be used to monitor the evaporation of the quenching agent. Cracking of a surface of the workpiece or the formation of cracks in the workpiece is generally undesirable and leads to the rejection of the workpiece. The cracking and cracking can be detected by sound sensors S1. Furthermore, the volume at which the quenching medium evaporates can also be used to determine the surface temperature. The sound sensor S1 is used for this purpose. To monitor static and dynamic pressures in the fixture 1, in particular a pressure drop across the workpiece 2, pressure sensors P3 and P4 are also provided close to the workpiece 2. A volume flow sensor 14 is integrated into the valve 11 shown as an example. Valves 11 are provided either on each channel 4 or on groups G1 to G6 of channels 4.For the sake of clarity, a detailed representation of each individual valve is omitted.

[0049] It is conceivable, accordingly Figure 4 The valves 11 are formed by an upper valve plate 17 and a lower valve plate 18. The lower valve plate 18 is arranged so as to be rotatable relative to the upper valve plate 17 in order to bring bores 19 in the lower valve plate 18 into overlap with bores 20 in the upper valve plate 17. According to this embodiment, the valve plates 17 and 18 can be rotated relative to one another. A displacement of the valve plates 17 and 18 is also possible to achieve a further degree of freedom for opening and closing the valves, but is not shown.

[0050] The valves 11 and the sensors TC1 to TC7, P1 to P4, S1 are coupled in a signal-transmitting or signal-conducting manner to a control device 14 which is designed to process the signals detected by the sensors and to generate actual values ​​therefrom and, in the event of a deviation of an actual value from a setpoint value, to control the valves 11 in a differentiated manner in order to achieve a definable, controllable local volume flow.

[0051] An example is in Figure 2 a digital model of the fixture 21 implemented in a control device 15 is implemented, which is used in the control device 15 to anticipate a temperature distribution close to the workpiece 2 and to output correction values ​​for the regulation of the volume flows Q1 to Q6 in the respective groups G1 to G6 of channels 4.

[0052] After recording an actual temperature and a cooling rate by the temperature sensors TC1 to TC7, the pressures and a pressure drop at the pressure sensors P3 and P4, and / or the sound at the sound sensor S1, an assignment is made to a currently available control actual value for control elements (valves 11) for controlling the volume flows Q1 to Q6. In parallel or subsequently, an ideal temperature and a cooling rate, which ideally should be present on the workpiece in order to achieve predefined material properties, are determined using the digital model of the fixture 21. These measured values ​​can be validated using the digital model 22 of workpiece 2. Furthermore, the digital model 22 can be used to calculate the actual temperatures on and in the workpiece from the temperatures only recorded near workpiece 2.From this, an ideal temperature and a cooling rate, which ideally should be present on the workpiece 2, can be determined by adjusting and comparing the digital model 21 with the actual fixture 1. Subsequently, a control setpoint for the volume flows Q1 to Q7 (or a setting value for the valves 11) is set based on a difference between the actual temperature and an ideal temperature. Furthermore, the signals obtained from the pressure sensors P1 to P4 and the sound sensor S1 can be used to further detail or specify the current state of the fixture 1 and the workpiece 2 located therein.

[0053] Furthermore, a digital model of the workpiece 22 is implemented in a control device 15, wherein a current temperature distribution and an imminent temperature distribution on the workpiece 2 are anticipated on the basis of the signals and correction values ​​for the regulation of the volume flows in the respective channels 4 are output.

[0054] In the control device 15, a process for cooling or quenching a workpiece 2 inserted in the holder 3 is carried out with the Figure 3illustrated steps 101 to 103. Step 101 provides for the detection of a locally increased or reduced cooling rate requirement on a workpiece 2 inserted in a holder 3 of the fixture 1. Step 102 provides for the creation of a control setpoint for control elements 11, 17, 18 for controlling a volume flow Q1 to Q6 in the fixture 1. Step 103 provides for the control of the volume flows Q1 to Q6 of quenching medium in channels 4 each ending in the holder 3, individually or bundled into groups G1 to G6, in order to specifically influence the cooling rate on the workpiece 2 in a location-specific manner according to the increased or reduced requirement during a quenching process. List of reference symbols

[0055] 1Fixture 2Workpiece 3Holder 4Channels 5Mandrel 6Holder 7Outside 8Bottom 9Top 10Inside 11Valve 12First supply chamber 13Second supply chamber 14Flow rate sensor 15Control device 16Outlet 17Upper valve plate 18Lower valve plate 19Bore ​​20Bore 21Digital model of the fixture 22Digital model of the workpiece AAxial direction G1First group G2Second group G3Third group G4Fourth group G5Fifth group G6Sixth group Q1First flow rate Q2Second flow rate Q3Third flow rate Q4Fourth flow rate Q5Fifth flow rate Q6Sixth flow rate P1First pressure sensor P2Second pressure sensor P3Third pressure sensor P4Fourth pressure sensor RRadial direction TC1First temperature sensor TC2Second temperature sensor TC3 third temperature sensor TC4 fourth temperature sensor TC5 fifth temperature sensor TC6 sixth temperature sensor TC7 seventh temperature sensor

Claims

1. Fixture (1) for quenching workpieces (2), comprising: - a lockable receptacle (3) for a workpiece (2) and a plurality of fluid-conducting channels (4) for feeding quenching medium into the receptacle (3) and thereby to the workpiece (2), characterized in that - volume flows (Ql, Q2, Q3, Q4, Q5, Q6) of quenching medium to groups (Gl, G2, G3, G4, G5, G6) of channels (4) can be regulated in order to selectively influence a cooling rate on the workpiece (2) during a quenching process.

2. Fixture according to claim 1, characterized in that annularly arranged groups (Gl, G2, G3, G4, G5, G6) of channels (4) are provided for flowing onto an annular workpiece (2), wherein - a first group (Gl) is arranged in the receptacle (3) for flowing through the channels (4) assigned to it on a radially outer side (7) of the annular workpiece (2), namely against a radial direction (R) from the outside, a second group (G2) is arranged for flowing onto the outer side (7) through the channels (4) assigned to it, in a planar manner from an axially lower underside (8) to an axially upper top side (9) of the annular workpiece (2), a third group (G3) is arranged to flow through the channels (4) assigned to it on the underside (8), a fourth group (G4) is arranged for flowing onto a radially inner side (10) of the annular workpiece (2) through the channels (4) assigned to it, namely over a large area from the underside (8) to the top side (9), a fifth group (G5) is arranged for radial outward flow through the channels (4) assigned to it on the inside (10) of the annular workpiece (2), and a sixth group (G6) is arranged for flow through the channels (4) assigned to it on the top side (9).

3. Fixture (1) according to claim 1 and / or 2, characterized in that the volume flow (Ql, Q2, Q3, Q4, Q5, Q6) is regulated via valves (11) which are connected on the outlet side to the channels (4) and on the inlet side at least to a supply chamber (12, 13) pressurized with quenching medium in a fluid-conducting manner.

4. Fixture (1) according to one of claims 1 to 3, characterized in that the valves (11) are proportional valves which have a variable flow behaviour depending on an input signal.

5. Fixture (1) according to one of claims 1 to 4, characterized in that volume flow sensors (14) are provided in the channels, in particular close to the workpiece (2), which are designed to detect a volume flow (Ql, Q2, Q3, Q4, Q5, Q6) directed to the channels (4) and to generate a signal.

6. Fixture (1) according to one of claims 1 to 5, characterized in that temperature sensors (TC3, TC4, TC5, TC6) are arranged in the fixture, in particular close to the workpiece, which are designed to detect a temperature radiated by the workpiece (2), and to generate a signal.

7. Fixture (1) according to one of claims 1 to 6, characterized in that a sound sensor (Sl) is arranged in the fixture (1), in particular close to the workpiece (2).

8. Fixture (1) according to claim 5, wherein the volume flow sensors (14) are integrated into the valves (11).

9. Fixture (1) according to one of claims 1 to 8, characterized in that the valves are formed by an upper valve plate (17) and a lower valve plate (18), which is arranged slidable relative to the upper valve plate (17) in order to bring bores (19) in the lower valve plate (18) into overlap with bores (20) in the upper valve plate (17).

10. Fixture (1) according to one of claims 1 to 9, characterized in that the valves (11) and the sensors are coupled in a signal-transmitting manner to a control device (15) which is configured to process the signals detected by the sensors and to generate actual values therefrom and, in the event of a deviation of an actual value from a setpoint value, to actuate the valves (11) in a differentiated manner in order to achieve a definable controllable local volume flow (Ql, Q2, Q3, Q4, Q5, Q6).

11. Fixture (1) according to one of claims 1 to 10, characterized in that a digital model of the fixture (21) is implemented in a control device (15), which is used in the control device (15) to anticipate a temperature distribution close to the workpiece and to output correction values for the regulation of the volume flows (Ql, Q2, Q3, Q4, Q5, Q6) in the respective groups (Gl, G2, G3, G4, G5, G6) of channels (4).

12. Fixture according to one of claims 1 to 11, characterized in that a digital model of the workpiece (22) is implemented in a control device (15), which anticipates a flow distribution (15) and a resulting temperature distribution on the workpiece (2) in the control device (15) based on a position and a direction of the channels (4) and outputs correction values for the regulation of the volume flows (Ql, Q2, Q3, Q4, Q5, Q6) in the respective channels (4).

13. Method, which can be stored in a control unit (15) for controlling a fixture (1), in order to cool a workpiece which can be placed in a receptacle, characterized by the steps: i. Detecting a locally increased or decreased requirement for a cooling rate on a workpiece (2) inserted in a receptacle (3) of the fixture (1), ii. Creating a control setpoint for control elements for controlling a volume flow (Ql, Q2, Q3, Q4, Q5 or Q6) in the fixture (1), Controlling the volume flows (Ql, Q2, Q3, Q4, Q5, Q6) of quenching medium in channels ending in the fixture, in each case individually or bundled according to groups, in order to influence the cooling rates of the workpiece (2) during a quenching process in a targeted manner at certain points according to the increased or reduced requirement.

14. The method according to claim 13, characterized by the steps of: i. Detecting an actual temperature and a cooling rate by at least one, preferably several temperature sensors (TC3, TC4, TC5, TC6, TC7) arranged close to the workpiece (2), and assignment to a currently available actual control value for control elements (11, 17, 18) for controlling the volume flows (Ql, Q2, Q3, Q4, Q5, Q6), ii. Detecting an ideal temperature and a cooling rate, which should ideally be present on the workpiece (1) in order to achieve predefined material properties, using a digital model of the workpiece (22) stored in a control device, iii. Creating the control setpoint according to point ii. of claim 13 based on a difference between the actual temperature and the ideal temperature.

15. The method according to claim 14, characterized by the steps of: i. Detecting a noise level in the receptacle (3) by means of a sound sensor (Sl), ii. Detecting a pressure difference before and after the workpiece in the receptacle (3) by several pressure sensors (PI, P2, P3, P4), iii. Completing an actual state of the real workpiece (2) based on the pressure difference and the noise level.