Induction device, in particular for an electrodynamic brake, and electrodynamic brake

Abstract

The invention relates to an induction device (300), in particular for an electrodynamic brake (100), wherein at least one support element (400) has a plurality of openings (402), and a plurality of pins (410) are divided into multiple pin groups (416), one pin group (416) being arranged in each opening (402). The invention additionally relates to an electrodynamic brake (100).

Description

[0001] Induction device, in particular for an electrodynamic brake, and electrodynamic brake

[0002] The present invention relates to an induction device, in particular for an electrodynamic brake, and an electrodynamic brake with this induction device.

[0003] Eddy current brakes are known in the prior art. For example, DE 950 939 B discloses an eddy current brake in which the pole cores of the inductor are arranged on either side of an armature movable relative to the inductor. The armature consists of one or more bodies that form the eddy current path and are highly electrically conductive, and of parts that conduct the magnetic flux well and extend through the first-mentioned body or bodies. The parts that conduct the magnetic flux project beyond the body or bodies that form the eddy current path on both sides, so that the ends of these parts form projections that improve the cooling of the armature.

[0004] DE 102016108646 B4 discloses an electrodynamic brake with a magnetic device for providing a magnetic field, which has at least two pole elements and interacts with an induction device. The induction device is arranged such that, in a braking mode, it is at least partially exposed to a magnetic field provided by the pole elements of the magnetic device and is designed such that electrical currents are induced therein in a variable magnetic field. The induction device and the pole elements of the magnetic device are movable relative to one another along a predetermined movement path.

[0005] With the latter electrodynamic brakes and their material structure, which consists of steel pins and perforated plates, it is already possible to significantly reduce the skin effect in the eddy current brake and thus achieve improved current distribution. In particular, the positioning plates that center the steel pins can significantly increase the surface area for cooling the brake, thus increasing the power density. The object of the present invention is to propose an improved electrodynamic brake with improved performance.

[0006] This object is achieved according to the invention by an induction device according to the features of claim 1 and an electrodynamic brake according to the features of claim 13. Advantageous embodiments are specified in the respective associated subclaims.

[0007] According to this, the object is achieved by an induction device, in particular for an electrodynamic brake, wherein the induction device comprises at least one support element and a plurality of pins, and wherein the at least one support element has a plurality of openings. The plurality of pins is divided into several pin groups, such that each pin group has a portion of the plurality of pins, wherein one of the pin groups is arranged in each individual opening of the at least one support element.

[0008] The invention is based on the idea of ​​reducing the size of individual pins and combining several pins into pin groups for arrangement in the individual openings of the at least one support element.

[0009] The use of comparatively smaller, individual pins enables the reduction of the so-called skin effect within the individual pins.

[0010] The pin clusters enable optimized current density at the support elements, which also function as conducting plates. A higher or optimized power density can be achieved.

[0011] At the same time, compared to the use of individual pins per opening of the support element, a pin fill factor or total fill factor can be maintained or preserved in this way. The total fill factor refers to a cross-sectional area of ​​the arranged pins compared to the remaining surface of the support element in a corresponding plan view. An advantageous embodiment can consist of the openings and thus the pin groups being distributed in a uniform grid or pattern. This grid or pattern is advantageously only interrupted or discontinued in those partial areas of the support element where the complete area for an opening with a sufficiently adjacent web width (web area) is no longer available.

[0012] The openings are preferably designed perpendicular to the support element, so that a theoretical central opening axis runs perpendicular to the surface of the support element. Ideally, the openings are all identical or essentially identical.

[0013] Alternatively, the design of the openings can vary, preferably so that a symmetrical pattern is achieved along the surface of the individual support element. The pin groups can therefore be designed to correspond to the respective opening.

[0014] The support element is advantageously made of an electrically conductive material with low magnetic permeability. Ideally, the support elements can be made of aluminum or copper.

[0015] The pins can advantageously be made of a material with high magnetic permeability, such as steel. The steel can be, for example, type 1.0718.

[0016] In one embodiment, the openings can have a circular or polygonal basic structure. A hexagonal honeycomb structure can be provided as the basic structure, so that the support element has a grid or grid region with hexagonal openings.

[0017] A hexagonal basic structure results in a particularly uniform distribution of the webs, web nodes, or web surfaces surrounding the openings, allowing magnetic and electric field lines to flow through the material of the support element particularly evenly. Furthermore, a uniform flow is achieved because extreme bottlenecks can be avoided.

[0018] Although a hexagonal basic structure is particularly advantageous, the openings can also have a triangular, square, or other polygonal basic structure. Overall, basic opening structures that result in very uniform webs or web surfaces as a supporting grid are advantageous in order to achieve the greatest possible density and uniform distribution along the surface of the respective support element.

[0019] In an improved embodiment, the group of pins can be cast into the openings of at least one support element by means of a casting element, preferably comprising epoxy resin or acrylic resin. In particular, the groups of pins can be cast into all openings of all support elements.

[0020] The casting material should be such that, when cured, it is permanently stable at temperatures between 120°C and 200°C, and particularly at temperatures between 120°C and 160°C. It may therefore be advantageous to use an epoxy resin or an acrylic resin as the casting material.

[0021] In a further improvement of this embodiment, it can be provided that the pin groups are cast into the openings of the uppermost and lowermost support elements by means of a casting element, preferably comprising epoxy resin or acrylic resin, in particular in the case of three or more support elements, they are cast exclusively into the openings of the uppermost and lowermost or the two outer support elements.

[0022] This allows for optimal cooling in the interior and interstices of the induction device, without compromising the strength and positional stability of the pin groups. A further improvement could be achieved by casting or flowing the casting material over or around the ends of the pins of the pin groups in the final position in the support element, and allowing the casting material to flow into the gap areas (interstices) for at least part of the length of the pins and harden there.

[0023] In a further advantageous embodiment, an additional sealing element, independent of the support element, is provided as a frame, grid, and / or mesh element in at least some of the openings, through which a pin group or the pins of a pin group are passed during assembly. The sealing element serves in particular to determine the position of the individual pins of a pin group and as a seal for the casting material in the area of ​​the opening.

[0024] In an advantageous embodiment, the sealing element is introduced as a circumferential frame or as a guide for individual pins by means of an additive manufacturing process directly into at least a portion of the openings of a support element.

[0025] In principle, it is advantageous to achieve the highest possible density of pins in the openings. Therefore, in an improved embodiment, it can be provided that the pins of each pin group have a cross-sectional area A and each individual opening of the at least one support element has a cross-sectional area B, wherein the ratio

[0026] - the total number of cross-sectional areas A of all pins in a single pin group

[0027] - the opening area B of the respective opening is in the range of 0.85 + / - 0.1, advantageously in the range of 0.85 + / - 0.05 and in particular in the range of 0.85 + / - 0.01.

[0028] The packing density is advantageously such that the generally cylindrical pins are arranged parallel and in a dense packing to one another.

[0029] Furthermore, good cooling and permeability must be ensured so that the energy converted into heat can be dissipated in the case of high induction. It has been found that it can be advantageous to arrange a circumferential web with a web width between two openings and to maintain the following ratio: The web width to the inner radius of the opening is in the range of 0.45 + / - 0.15, particularly in the range of 0.45 + / - 0.08.

[0030] The web width describes the smallest web width between two openings of a support element.

[0031] Analogously, an advantage may be achieved if a circumferential web with a web width is formed between each two openings of the at least one support element, wherein the ratio of half the web width to the width of the opening is in the range of 0.05 to 0.3, in particular in the range of 0.08 to 0.12. In this way, sufficient internal spaces and flow channels can be provided for heat dissipation, while simultaneously ensuring a high pin density.

[0032] This shows the particular advantage of a hexagonal honeycomb structure of the openings, because it creates a very uniform, stable web structure with only small and only slightly enlarged node areas.

[0033] In a further, improved embodiment, it can be provided that the pins of a pin group are arranged in a longitudinal direction so as to touch one another at least over a partial length, in particular each pin of a pin group of at least three adjacent pins is arranged so as to touch one another along at least a partial length.

[0034] In a further improved embodiment, it can be provided that at least a portion of the outer pins of a pin group are in contact with the support element.

[0035] This means that the outer pins are in contact with one of the opening edges, allowing support to be provided. With a cylindrical pin and a straight opening edge, the two geometries are tangent along a contact line.

[0036] To prevent short circuits and ensure optimal formation of magnetic field lines, a further improvement could be to have at least a portion of the pins coated with an electrically insulating material on their outer surface. This could be an addition, such as a phosphate coating, or another electrically insulating coating.

[0037] For the later installation of the induction device with a one-sided magnetic device, an improved embodiment can consist in providing a return element which is preferably made of a soft magnetic composite or of a ceramic ferrite, in particular is designed as a ferrous return element.

[0038] This return element can form a closing element and has, for example, the shape of a plate or a ring.

[0039] In particular, the return element can be in contact with one longitudinal end of the pins or groups of pins.

[0040] When installed, the return element is preferably arranged on the side of the induction device facing away from the poles or pole pieces. The return element is arranged parallel to the support elements.

[0041] The pins or groups of pins can be cast into or on the return element.

[0042] Within the meaning of the present invention, various return path and / or excitation variants can be provided, as are known, for example, from DE 10 2016 108 646 B4. For example, a disk-shaped return path element or a helically wound steel strip can be provided to form a disk-shaped return path element.

[0043] Furthermore, the excitation coils or pole elements can be arranged, for example, on one side or, by replacing the return element, on both sides of the induction device. The excitation coils or pole elements can be designed exclusively as north poles, or the pole elements can be provided at least partially in the form of permanent magnets instead of core-winding coils. Particularly in the case of a double-sided arrangement of pole elements, only north poles or south poles can be arranged on one side of the respective carrier plate.

[0044] In the sense of the present invention, the pole elements can in particular be provided as a rotor, wherein the induction device can be provided as a stator.

[0045] In a further improved embodiment, it can be provided that at least one spacer is arranged between two adjacently arranged support elements of the plurality of support elements, in particular in the form of a silicone cord, a plastic cord, a silicone ring, a plastic ring or the like, so that a minimum distance is provided between two adjacently arranged support elements.

[0046] For this purpose, one or more flexible spacers, such as one or more silicone cords, can be arranged between two support elements. In particular, silicone or plastic rings can also be placed around a plurality of pin groups, on which a subsequent support element rests or rests. Advantageously, the support elements arranged one above the other provide an open, permeable structure.

[0047] According to a further advantageous embodiment of the invention, the induction device can have at least one cover element, in particular at least one cover plate, wherein the at least one cover element is provided opposite one and / or in the region of a longitudinal end of the plurality of pins and the cover element has an electrical conductivity which is lower than the electrical conductivity of the at least one support element.

[0048] For example, the lid element may comprise a material such as stainless steel or the like.

[0049] Furthermore, the cover element or the cover plate can preferably be arranged in contact with the casting element.

[0050] In particular, the cover element can be provided on a side of the induction device opposite the return element.

[0051] If pole elements or coils are provided on both sides of the induction device, the induction device can be designed with two cover elements, wherein a cover element is arranged on or in the region of one of the longitudinal ends of the plurality of pins, preferably adjacent to the respective casting element or casting material.

[0052] Preferably, the cover element has the lowest possible electrical conductivity.

[0053] By having a low electrical conductivity of the lid element, the casting element, for example an epoxy resin, can be protected from strong or excessive heat input.

[0054] The invention further encompasses an electrodynamic brake having a magnetic device for providing a magnetic field. The magnetic device preferably has at least one pole element and an induction device according to the present invention.

[0055] Preferably, the induction device can be arranged such that, in a force mode, it is at least partially exposed to a magnetic field provided via the pole elements of the magnetic device, and wherein the induction device and the pole elements of the magnetic device are movable relative to one another along a predetermined movement path.

[0056] Further details and advantages of the invention will now be explained in more detail with reference to embodiments shown in the drawings.

[0057] They show:

[0058] Fig. 1 is a perspective view of an embodiment of the induction device in a first partial view I and an enlarged section in a second partial view II;

[0059] Fig. 2 is a sectional view of an embodiment of the induction device in perspective view;

[0060] Fig. 3 is a perspective view of an embodiment of the induction device in a partially finished state;

[0061] Fig. 4 is a perspective view of an embodiment of the induction device with cast-in pin groups; and

[0062] Fig. 5 is a perspective view of an embodiment of the electrodynamic brake in a partial section.

[0063] Fig. 1 shows an embodiment of an induction device 300 for an electrodynamic brake 100.

[0064] According to Fig. 1, the induction device 300 may have seven horizontal support elements 400, each having a plurality of openings 402.

[0065] In each opening 402, a group of pins 410 is arranged as a pin group 416 (pin / pin cluster). In partial image I, the pin group 416, each with a plurality of pins 410, is shown schematically in a simplified manner as a cylinder.

[0066] The pin groups 416 penetrate all seven support elements 400.

[0067] Longitudinal axes of the pin groups 416 are arranged congruently or coaxially with the opening axis 404 of the respective opening 402 as shown in Fig. 1.

[0068] A simplified wall element 418 is arranged inside and outside of the induction device 300, which is part of the electrodynamic brake 100 and delimits the induction device 300 on both sides of the narrow sides.

[0069] A plurality of pole elements 102 can be arranged along at least one broad side of the induction device 300, of which pole elements 102 are indicated in Fig. 1 below the induction device 300.

[0070] The pole elements 102 have a remote core 112 and an excitation coil 110 running around the core 112.

[0071] The excitation coil 110 can be energized in a controlled and / or regulated manner by means of a control unit (not shown) from a power source (also not shown).

[0072] In the intended operation of the shown induction device 300 or the electrodynamic brake 100, the induction device 300 is rotatably mounted by a shaft (not shown) and the energized pole elements 102 are stationary.

[0073] A force transmission and negative acceleration of the induction device 300 can occur when the coils 110 of the pole elements 102 are energized and act on the induction device 300, as is shown and described in detail, particularly in Fig. 5. In partial image II of Fig. 1, the hexagonal basic structure of the openings 402 is shown in detail as a top view of a section of the induction device 300.

[0074] The multitude of hexagonal openings 402 results in a honeycomb-like grid of webs 406.

[0075] In each opening 402, a pin group 416 is arranged which is aligned with the opening axis 404.

[0076] For example, the narrow width 420 of the opening 402 can be 6.3 mm and can thus have an opening area of ​​31.17 mm 2 have.

[0077] In the example shown in part II of Fig. 1, a pin group 416 comprises a total of 37 individual pins 410.

[0078] For example, the pins 410 can each have a pin width of 422 or a diameter of 1 mm and thus a total area in the opening of 29.06 mm 2 prove.

[0079] Furthermore, the web width 408 outside the node areas can be 1.38 mm. This results in a theoretical coverage area of ​​38.37 mm 2 , which is calculated from the aforementioned opening area plus half the web area around the respective opening 402.

[0080] In the example above, this results in a coverage rate of 0.964 pins per mm 2 Area of ​​the support element 400.

[0081] In particular, an occupancy rate of up to 0.98 can be achieved if the web width 408 is further reduced.

[0082] Such a coverage level would be impossible or only possible with great effort for a uniform, non-grouped arrangement of individual pins 410. Furthermore, despite the high coverage level, a sufficient web width 408 can be ensured. Adequate heat dissipation via support elements 400 can be ensured during operation of the induction device 300.

[0083] In Fig. 2, a further embodiment of an arrangement of an induction device 300 is shown as an enlargement in vertical section and in perspective.

[0084] The adjacent wall element 418 is arranged in the left edge of Fig. 2.

[0085] For example, the opening width 420 of the hexagonal openings 402 may be 6.3 mm, the land width 408 may be 1.38 mm, and the diameter 422 of an individual pin 410 may be 1.0 mm.

[0086] In Fig. 2, a single opening 402 is shown without pin group 416 for illustrative purposes.

[0087] The support element 400 can have a material thickness 428 of, for example, 4 mm and in particular a material such as aluminum.

[0088] A plurality of support elements 400 can be arranged between the two casting elements or casting resins 426. Furthermore, at least one cover element or cover plate 440 can be provided, which is preferably arranged in a region of a longitudinal end of the plurality of pins 410. A permeable structure for a flowing coolant is formed by flow channels 436 between the individual pin groups 416 and the support elements 400 (see also gaps 412 according to Fig. 1).

[0089] It is generally understood that the information relative to gravity, such as "up," "down," "lower," "set," "upright," "hanging," etc., serves only to illustrate and describe the elements shown in a specific position. This information is not to be understood as limiting the orientation of the induction device during use or assembly and applies analogously to a different orientation, such as a vertical orientation of the induction device.

[0090] Fig. 3 shows the pin groups 416 according to an embodiment, which are set in the lowermost support element 400 and aligned perpendicular thereto.

[0091] A wall element 418 is arranged to the left and right of the induction device 300, wherein cooling channels 104 are provided in the radially outer wall element 418 shown on the right.

[0092] The main geometry 424 of the induction device 300 can be a ring or a crown as shown in Fig. 3.

[0093] Fig. 3 shows the induction device 300 in a manufacturing step prior to completion. In particular, according to Fig. 3, (at least) one upper support element 400 can be lowered onto the illustrated pin groups 416 for completion. This support element can then be finally cast, as shown in Fig. 4, with the ends of the pin groups 416 and with the aid of a casting element made of Z-resin, preferably epoxy resin or acrylic resin.

[0094] In Fig. 4, the induction device 300 according to Fig. 3 is shown after a support element 400 (not shown) has been cast with the pin groups 416 by means of a casting element / casting resin 426.

[0095] In this case, both the spaces above the webs 406 and the web nodes 434 were cast over and cured. Additionally, it is possible to cast over the free ends of the pins 410 of the pin groups 416, so that the casting resin 426 can penetrate to a certain extent between the individual pins 410 into the interstices and cure there.

[0096] Figure 5 shows the electrodynamic brake 100 in an open and partially sectioned state. The induction device 300 is attached to the schematically illustrated shaft 106 and represents the component to be braked. The pole elements 102, shown in parallel section, are arranged and secured to a carrier plate 108 shown at the front, which does not rotate with the shaft 106 and is stationary.

[0097] The pole elements 102 each have a core 112 with a radially outer wider side and a radially inner, narrower side, so that they are formed similar to a ring segment.

[0098] A multi-layer excitation coil 110 is arranged around each of the cores 112, which can be controlled in a manner not shown in detail and through which current can flow.

[0099] The induction device 300 is designed analogously to the above embodiments, i.e. it has a plurality of pin groups 416.

[0100] The adjacent and parallel legs of the excitation coils 102 of adjacent pole elements 102 are electrically flowed through with a current direction 120 in the same direction, which in the example for the two parallel legs is directed radially outwards.

[0101] Thus, in the embodiment shown in Fig. 5, magnetic field lines 430 are formed, which emerge from the viewing plane at the left core 112 and enter the right core 112 shown in section.

[0102] In parallel, in a known manner, as described for example in DE 102016 108 646 B4, the pins 410 are electrodynamically acted upon, so that the induction device 300 is decelerated.

[0103] In the example shown, the pole elements 102 are arranged on both sides of the broad side of the induction device 300. Alternatively, the formation of the magnetic field can also be ensured via a ferrous or ferritic return element.

[0104] 100 Brake

[0105] 102 pole element

[0106] 104 Cooling channel

[0107] 106 Wave

[0108] 108 carrier plate

[0109] 110 Excitation coil

[0110] 112 Kem

[0111] 120 Current direction 00 Induction device 00 Support element 02 Opening 04 Opening axis

[0112] 406 jetty

[0113] 408 web width

[0114] 410 pen

[0115] 412 space

[0116] 416 Pin group (pin cluster)

[0117] 418 wall element

[0118] 420 width

[0119] 422 web width

[0120] 424 Main geometry

[0121] 426 Casting resin / casting element

[0122] 428 material thickness

[0123] 430 field lines, magnetic

[0124] 434 web knots

[0125] 436 flow channels

[0126] 440 cover element / cover plate

[0127] A cross section

[0128] B Opening area

Claims

Patent claims Induction device (300), in particular for an electrodynamic brake (100), wherein the induction device (300) comprises at least one support element (400) and a plurality of pins (410), the at least one support element (400) having a plurality of openings (402), wherein the plurality of pins (410) is divided into a plurality of pin groups (416) such that each pin group (416) has a part of the plurality of pins (410), and wherein one of the pin groups (416) is arranged in each of the individual openings (402) of the at least one support element (410). Induction device (300) according to claim 1, characterized in that the openings (402) have a circular or a polygonal basic structure, in particular a hexagonal honeycomb structure as the basic structure.Induction device (300) according to claim 1 or 2, characterized in that the groups of pins (410) are cast into the openings (402) of at least one support element (400) by means of a casting element (426), preferably epoxy resin, in particular are cast into all openings (402) of all support elements (400). Induction device (300) according to claim 1 or 2, characterized in that the groups of pins (410) are cast into the openings (402) of the uppermost and lowermost support element (400) by means of a casting element (426), preferably epoxy resin, in particular in the case of three or more support elements (400) exclusively into the openings (402) of the uppermost and lowermost. lowermost support element (400). Induction device (300) according to one of the preceding claims, characterized in that the pins (410) of each pin group (416) have a cross-sectional area A and each individual opening (402) of the at least one support element (400) has a cross-sectional area B, wherein the ratio - the total number of cross-sectional areas A of all pins (410) of a single pin group (416) - the opening area B of the respective opening (402) is in the range of 0.85 + / - 0.1, in particular in the range of 0.85 + / - 0.

05. Induction device (300) according to one of the preceding claims, characterized in that a circumferential web (406) with a web width (408) is formed between each two openings (402) of the at least one support element (400), wherein the ratio of half the web width (408) to the width (420) of the opening (402) is in the range of 0.05 to 0.

3. Induction device (300) according to one of the preceding claims, characterized in that the pins (410) of a pin group (416) are arranged in longitudinal extension so as to touch one another at least over a partial length, in particular each pin (410) of a pin group (416) of at least three adjacent pins (410) is arranged so as to touch one another along at least a partial length.Induction device (300) according to one of the preceding claims, characterized in that at least a portion of the outer pins (410) of a pin group (416) are in contact with the support element (400). Induction device (300) according to one of the preceding claims, characterized in that. at least a portion of the pins (410) comprise an electrically insulating material as an attachment or are coated with a coating, in particular comprise a phosphate-containing material as an attachment. Induction device (300) according to one of the preceding claims, characterized in that a return element is provided, which is preferably made of a soft magnetic composite or of a ceramic ferrite, in particular an iron-containing return element (414). Induction device (300) according to one of the preceding claims, characterized in that at least one spacer (432) is arranged between two adjacently arranged support elements (400) of the plurality of support elements (400), in particular in the form of a silicone cord, a plastic cord, a silicone ring, a plastic ring, or the like, so that a minimum distance is provided between two adjacently arranged support elements (400).Induction device (300) according to one of the preceding claims, characterized in that the induction device (300) has at least one cover element (440), in particular at least one cover plate, which is provided opposite and / or in the region of a longitudinal end of the plurality of pins (410), wherein the cover element has an electrical conductivity that is lower than the electrical conductivity of the at least one support element (400). An electrodynamic brake (100) with a magnetic device for providing a magnetic field, which has at least one pole element (102) and an induction device (300) according to one of the preceding claims.

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