Patent Application
20240399390
This application claims priority to German patent application no. 10 2023 205 217.2 filed on Jun. 5, 2023, the contents of which are fully incorporated herein by reference.
The present disclosure is directed to a housing for a tool, such as a quenching spray or a sensor device, which is used in inductive hardening and includes an improved cooling arrangement.
To harden workpieces, use may be made, inter alia, of an induction hardening system, by means of which an entire workpiece, but also individual regions of a workpiece, can be hardened. For this purpose, the workpiece can be heated locally to up to 1000° C. After being heated to a required hardening temperature, the workpiece subsequently has to be quenched. During the quenching, a quenching fluid, such as water, is applied to the workpiece using a quenching spray.
Since the quenching takes place immediately after the heating, the quenching spray has to be brought into the vicinity of the workpiece, which is heated to a temperature of up to 1000° C., as a result of which the materials of the quenching spray and the quenching spray itself are exposed to very high temperatures. For this reason, quenching sprays and other induction hardening tools that are exposed to the high temperatures during the induction hardening, such as sensor housings, may be produced from high-alloy materials in order to withstand the radiated heat and convection heat to which they are exposed. They can be produced by casting, 3D printing, welding, etc. The materials may be ceramic or stainless steel alloys, which are usually expensive and/or require complex production processes in order to achieve only a low distortion and a high degree of precision despite the high melting point of the materials.
It is an aspect of the present disclosure to provide a quenching spray or, in general, a housing for a tool which is used in induction hardening, which is more cost-effective and easier to manufacture, but nevertheless can withstand the high temperatures in inductive metal processing and is not magnetic or ferromagnetic.
A housing of an induction hardening tool which is used in inductive hardening, in particular of a quenching spray or a sensor, is presented below.
In order for the tool or the housing of the tool to be able to resist the high radiated heat and convection heat, the housing has a cover element and a basic body connected thereto, wherein, furthermore, at least one coolant inlet and a coolant outlet are formed in the basic body, and at least one coolant passage, which is fluidically connected to the coolant inlet and the coolant outlet in order to actively cool the housing by means of a coolant, is formed in the cover element.
According to a preferred exemplary embodiment, the cover element is configured to receive at least part of a sensor device, in particular the measuring part of a sensor.
According to a further preferred exemplary embodiment, the housing is configured as a housing for a quenching spray of an induction hardening system, in which a plurality of through bores, which are designed as spray holes, are provided in the cover element. In addition, a quenching fluid inlet is formed in the basic body, the quenching fluid inlet being fluidically connected to the plurality of spray holes such that a quenching fluid can be applied to a workpiece to be quenched through the spray holes.
The active cooling makes it possible for the housing of the tool, i.e., in other words, the quenching spray or the sensor, to be positioned very close to the inductively heated and thus glowing workpiece (e.g. at a distance of 1 mm). This can be advantageous for quenching sprays to achieve high quenching pressures, cooling rates and thus a good utilization of the quenching fluid flow used. Sensors may also require short distances to the workpiece to be measured to ensure a stable and accurate measurement.
Furthermore, materials, such as plastic or aluminum, which have a relatively low melting point, can be used. By using such materials, a tool or a quenching spray can be manufactured with very high precision and low distortion, and therefore the production costs are low and the production process simplified. The use of materials with a low melting point and the associated lower strength also make it easier to rework the tools (e.g. drilling small holes, milling surfaces, etc.).
The quenching fluid or another coolant, such as compressed air or water, can be used as the coolant. If a coolant different from the quenching fluid is used in a quenching spray, it is of course advantageous that the coolant inlet and the quenching fluid inlet are formed as separate inlets. Furthermore, it is also possible additionally to apply cooling medium to the quenching fluid inlet in order to provide a particularly intensive cooling of the quenching spray or of the cover element before then quenching with the quenching fluid. In this case, the quenching fluid inlet can be charged either with cooling medium or with quenching fluid, for example by means of a valve arrangement. However, the above-mentioned separate inlets may also be advantageous when using quenching fluid as a coolant, since it is then ensured that fluid is sufficiently available for the quenching. It is also possible to individually adjust the quenching fluid flow and the coolant flow such that different quantities of fluid can be used for the quenching and for the cooling.
Alternatively, if the same fluid is used as the quenching fluid and the coolant, the quenching fluid inlet and the coolant inlet can be designed, of course, as a common inlet in quenching sprays. In this case, it may be advantageous furthermore to provide at least one fluid guiding device in the housing that is configured to guide the quenching fluid both to the spray holes and into the at least one coolant channel.
According to a further preferred exemplary embodiment, the cover element and the basic body are releasably connectable to each other. This makes it possible, with the same basic body, to provide different cover element solutions which are adapted to the respective application. For example, the cover elements may be designed with different spray hole designs to change the quenching fluid flow, the pressure or the direction and/or to adapt same to the workpiece to be quenched. Another example would be to adapt the cover element to different sensor sizes. It is thereby also possible to provide the cover element and the basic body from different materials such that the heat-exposed cover element is composed of a material that withstands higher temperatures than the basic body of the tool housing.
In the case of quenching sprays, the design of the cover element and basic body also allows the cover element itself to be adapted to different workpiece geometries and/or surfaces to be cooled. The number of spray holes, the size of the holes or the angle of inclination in relation to the workpiece surface and their relative movement can be adjusted by simply placing a correspondingly designed cover element thereon. In the case of a quenching process during the heat treatment, this means that the cooling intensity can be controlled to ensure a good structure, reduce the risk of cracks, ensure a good level of residual stresses, etc. Another advantage of a good use of the quenching fluid is that the typical initial vapor phase during the quenching can be reduced with water, for example, resulting in less quenching interference (inhomogeneous and slow quenching due to the insulating vapor phase on the hot steel surface) and faster quenching.
In addition, in particular in the case of bearing components which are inductively hardened, the adaptation of the cover element of the quenching spray to the component geometry can lead to a well-defined and locally controlled quenching intensity of the surface to be quenched, as a result of which the stresses during the quenching and the state of residual stress after quenching can be influenced, which results in a lower risk of cracks and better bearing performance because of homogeneous compressive stresses along the surface.
The interchangeability because of the releasable connection between the cover element and the basic body also enables the coolant supply and distribution to be controlled via different coolant passage configurations.
According to another preferred exemplary embodiment, the at least one coolant passage is arranged in at least one of the side walls of the cover element. This allows a major portion of the surface facing the workpiece to be hardened inductively to be used for the actual task of the tool, such as the quenching or the bearing and aligning of the sensor, while the housing as a whole is simultaneously cooled.
In this case, it is particularly advantageous if the cover element has a first, second, third and fourth side wall, wherein the first and second side wall and the third and fourth side wall are arranged opposite each other, and the coolant passage comprises a coolant supply section, a coolant discharge section and a first and a second coolant guiding section, wherein the first and second coolant guiding section are formed in the first and second side walls, the coolant supply section is formed in the third side wall, and the coolant discharge section is formed in the fourth side wall.
This enables particularly uniform and comprehensive cooling of the cover element.
Furthermore, it is advantageous if the coolant supply section and/or the coolant discharge section are each designed as a chamber-like compartment. This allows coolant to be sufficiently supplied or removed.
In order to ensure a particularly good distribution of the coolant in the cover element and to avoid, for example, the coolant accumulating in a region of the housing because of an installation position of the housing, it can furthermore be provided that at least one coolant distribution structure, which is designed to distribute the coolant in the cover element, is formed in the at least one coolant passage.
Said the coolant distribution structure may also be designed as a roughened surface, or additionally have a roughened surface. The roughened surface provides an increased surface area over which heat can be dissipated to the coolant, which further improves the cooling.
It is particularly preferred for the coolant distribution structure to be provided in the first and/or second coolant guiding section. According to a particularly preferred exemplary embodiment, the coolant distribution structure is configured in such a way that a plurality of, preferably parallel, coolant channels are formed in the first and/or second side wall. This enables a high coolant throughput and ensures that no matter how the housing is positioned, coolant will flow through the coolant passage.
In the case of a quenching spray, another preferred exemplary embodiment is provided in that the spray holes are arranged in such a way that they form a spray hole pattern, wherein, furthermore, a cutout, which is formed in the region of the spray hole pattern and is configured to receive the quenching fluid and to transfer same to the spray holes, is provided in the cover element. This can ensure that the same quantity of quenching fluid is applied to each spray hole.
This uniform application can be further increased if, as another preferred exemplary embodiment shows, an intermediate element is provided, which is arranged between the basic body and the cover element, wherein the intermediate element is configured to distribute the quenching fluid from the quenching fluid inlet uniformly in the direction of the spray holes. Of course, such an intermediate element may also be provided in a housing for a sensor.
In the case of an intermediate element for quenching sprays, it is also advantageous if the intermediate element has a plurality of elongated holes, which are preferably arranged in the region of the spray hole pattern. It can thereby already be ensured with the aid of the intermediate element that the quenching fluid is uniformly guided to all of the spray holes, and therefore the same quantity of quenching fluid is applied to each spray hole at the same time.
According to a further preferred exemplary embodiment, as an alternative or in addition to the cutout formed in the cover element, the cutout is also formed in the intermediate element.
Another embodiment comprises a spray head for a quenching device of an induction hardening system. The spray head includes a basic body and a cover element connected to the basic body. The basic body has a quenching fluid inlet, an entrance coolant passage and an exit coolant passage. The cover element has an entrance coolant passage in fluid communication with the basic body entrance cooling passage and an exit coolant passage in fluid communication with the basic body exit coolant passage and a plurality of cooling channels fluidically connecting the entrance coolant passage of the cover element to the exit coolant passage of the cover element. The cover element includes a quenching fluid compartment in fluid communication with the quenching fluid inlet and a plurality of through openings forming quenching fluid outlets in fluid communication with the quenching fluid compartment. In addition, the cover element is configured to prevent a coolant in the cover entrance coolant passage and the cover exit coolant passage and the plurality of cooling channels from mixing with a quenching fluid in the quenching fluid compartment. That is, the quenching fluid does not mix with the cooling fluid.
Further advantages and advantageous embodiments are specified in the description, the drawings and the claims. In particular the combinations of the features specified in the description and in the drawings are purely exemplary here, and therefore the features can also be present individually or in other combinations.
In the following text, the invention will be described in more detail using exemplary embodiments illustrated in the drawings. The exemplary embodiments and the combinations shown in the exemplary embodiments are purely exemplary here and are not intended to define the scope of protection of the invention. This is defined solely by the attached claims.
In the following text, identical or functionally equivalent elements are identified by the same reference signs.
As can be gathered from the figures, the quenching spray 1 comprises a multi-part housing 100 which, in the illustrated exemplary embodiment, has a cover element 200, an intermediate element 300, and a basic body 400. The individual components 200, 300 and 400 are assembled to form the housing 100, as can be gathered in particular from
Furthermore, the basic body 400 can be provided with different elements 300 or 200 for various purposes, for example, also to carry out different tasks. For example, it is conceivable for the basic body 400 to be used both as a basic body for a quenching spray and as a basic body for a sensor, with only the intermediate element 300 and the cover element 200 being correspondingly adapted and designed for the various tasks. For example, for a sensor housing, the intermediate element 300 can be designed as a sensor carrier and the cover element 200 can have corresponding cutouts so that the sensor or the sensor element can perform measurements.
Furthermore, it can be gathered from
Furthermore,
In order to ensure that the quenching fluid is also distributed in the cavity 404 at high quenching fluid pressures, the intermediate element 300 is further designed as a baffle plate, which distributes the flow of the quenching fluid. For this purpose, elongated holes 302 are formed in the intermediate plate, which form a fluid passage in the direction of the spray hole pattern 204. The elongated holes 302 in turn are covered by baffle structures 320, which deflect the quenching fluid entering the elongated holes 302 and distribute same in the fluid receiving compartment 203 of the cover element. The elongated holes 302 and the structures 320 ensure that the quenching fluid is not only transferred centrally into the spray hole pattern 204, but that the same pressure and the same quantity of quenching fluid are applied to all of the spray holes 202. It can thereby be ensured that quenching fluid is applied to the workpiece uniformly over the entire surface of the quenching spray.
Alternatively, of course, the intermediate element and/or the cover element can also be designed in such a way that a targeted, different, temporal and quantitative distribution of quenching fluid to the workpiece is possible. This can be used to control the stresses during the quenching and the resulting residual stresses in a targeted way, which can reduce the tendency to forming cracks.
Furthermore, the sectional view of
As mentioned above and can be gathered from the sectional view of
In the exemplary embodiment illustrated in
Furthermore,
To permit this active cooling of the housing 100, the housing 100, as mentioned above, has a coolant fluid inlet 506 and a coolant fluid outlet 508. In the housing 100 or in the individual parts 200, 300 and 400, corresponding coolant passages are formed, which connect the coolant inlet 506 to the coolant outlet 508 and guide the coolant through the housing and thus actively cool the latter.
The coolant passages, in particular those of the cover element, can additionally be equipped with a rough surface, as a result of which the surface which is cooled is increased as a whole (e.g., its surface area is increased), which in turn increases the cooling effect.
The coolant passage can be configured in different ways, wherein, in particular in the cover element 200, the side surfaces 210, 212, 214 and 216 are actively cooled to keep the cover element 200 at a temperature level at which no damage should be anticipated. In order to transfer the coolant from the coolant inlet 506 in the direction of the cover element 200, a passage opening 406 and 306 is respectively provided both in the basic element 400 and in the intermediate element 300, the passage openings being designed as slot-shaped passages and forming chamber-like sections in the illustrated exemplary embodiment.
Likewise, in order to transfer the coolant from the cover element 200 to the coolant outlet 508 again, a passage opening 408 and 308 is respectively provided both in the basic element 400 and in the intermediate element 300, the passage openings likewise being designed as slot-shaped passages and forming chamber-like sections in the illustrated exemplary embodiment.
The openings 406 and 306 serve as coolant supply openings and the openings 308 and 408 serve as coolant discharge openings.
The openings 406 and 306 are in turn fluidically connected to a chamber-shaped section 206, which is formed in the side wall 214 of the cover element 200, such that the coolant is transferred from the coolant fluid inlet 506 via the slot-shaped passage 406 of the basic body 400 into the slot-shaped passage 306 of the intermediate element 300 and from there into the chamber-shaped section 206, which thus serves as a coolant supply section of the cover element 200.
Similarly, in the opposite side wall 216 of the cover element, a chamber-like section 208 is also formed, which serves to guide coolant from the cover element 200 via the slot-shaped passage 308 of the intermediate element 300 and the slot-shaped passage 408 of the basic body back into the coolant outlet 508, such that the chamber-shaped section 208 serves as a coolant discharge section of the cover element 200.
In order to permit a fluidic connection between the coolant supply section 206 and the coolant discharge section 208, a coolant guiding section 220 and 222 is respectively formed in the side walls 210 and 212 of the cover element 200, which is shown in particular in
As mentioned above and in particular can be gathered from the sectional view of
Overall, the segmented structure formed from a plurality of partial elements makes it possible for the housing of the induction tool to be easily adapted to different applications. For example, the cover element 200 can be easily replaced in order, for example, to adapt different quenching sprays for different geometries with the workpieces to be quenched. It is also possible to use the same basic body 400 to represent a sensor housing instead of a quenching spray.
The active cooling of the housing also makes it possible for the housing to be made from other materials and easier-to-manufacture materials, thus enabling the use of materials that would not normally be able to withstand the high temperatures. Furthermore, the active cooling makes it possible for the tool to be able to be brought closer to the heated workpiece, which in turn is advantageous for the accuracy of measurements or the precision of the quenching.
Representative, non-limiting examples of the present invention were described above in detail with reference to the attached drawings. This detailed description is merely intended to teach a person of skill in the art further details for practicing preferred aspects of the present teachings and is not intended to limit the scope of the invention. Furthermore, each of the additional features and teachings disclosed above may be utilized separately or in conjunction with other features and teachings to provide improved housings of induction hardening tools.
Moreover, combinations of features and steps disclosed in the above detailed description may not be necessary to practice the invention in the broadest sense, and are instead taught merely to particularly describe representative examples of the invention.
Furthermore, various features of the above-described representative examples, as well as the various independent and dependent claims below, may be combined in ways that are not specifically and explicitly enumerated in order to provide additional useful embodiments of the present teachings.
All features disclosed in the description and/or the claims are intended to be disclosed separately and independently from each other for the purpose of original written disclosure, as well as for the purpose of restricting the claimed subject matter, independent of the compositions of the features in the embodiments and/or the claims. In addition, all value ranges or indications of groups of entities are intended to disclose every possible intermediate value or intermediate entity for the purpose of original written disclosure, as well as for the purpose of restricting the claimed subject matter.
| Number | Date | Country | Kind |
|---|---|---|---|
| 102023205217.2 | Jun 2023 | DE | national |
