ELECTRICAL DEVICE WITH INSULATOR BODY

Abstract

An electrical device (100, 200) is provided with a tubular metal sheath (110, 210, 250, 260) and with an insulator body (120, 160, 220, 251, 261), which is arranged in the interior of the tubular metal sheath (110, 210, 250, 260) and through which passes at least one tunnel-like opening (tunnel opening) (121, 122, 161, 162, 221, 252, 262). At least one section (131a, 132a, 171a, 172a) of a first electrical conductor (131, 132, 171, 172, 231) is arranged in the tunnel opening (121, 122, 161, 162, 221, 252, 262), in which the cross-sectional geometry of the tunnel opening (121, 122, 161, 162, 221, 252, 262) deviates from a circular shape.

Claims

1. An electrical device comprising: a tubular metal sheath; an insulator body arranged in an interior of the tubular metal sheath, at least one tunnel opening passing through the insulator body; an electrical conductor, wherein at least one section of the electrical conductor is arranged in the tunnel opening, characterized in that the cross-sectional geometry of the tunnel opening deviates from a circular shape.

2. An electrical device in accordance with claim 1, wherein the electrical conductor is a first electrical conductor and further comprising a second electrical conductor, wherein at least one section of the second electrical conductor is arranged in the tunnel opening.

3. An electrical device in accordance with claim 1, wherein the cross-sectional geometry of the tunnel opening is adapted to the cross-sectional geometry of the conductor section arranged in the tunnel opening.

4. An electrical device in accordance with claim 1, wherein the cross-sectional geometry of the tunnel opening is adapted to the cross-sectional geometry of the conductor section arranged in the tunnel opening such that the conductor section arranged in the tunnel opening is positioned or fixed or positioned and fixed by the cross-sectional geometry of the tunnel opening.

5. An electrical device in accordance with claim 4, wherein the cross-sectional geometry of the tunnel opening is adapted to the cross-sectional geometry of the conductor section arranged in the tunnel opening such that the conductor section that is positioned or fixed or positioned and fixed in the tunnel opening is arranged essentially gap-free in relation to one another.

6. An electrical device in accordance with claim 4, wherein the cross section of the tunnel opening has a circle segment-shaped or sector-shaped section for receiving and fixing a section of the electrical conductor having a circular cross section.

7. An electrical device in accordance with claim 4, wherein: the electrical conductor is a first electrical conductor and further comprising a second electrical conductor; at least one section of the second electrical conductor is arranged in the tunnel opening; the cross section of the tunnel opening has a circle segment-shaped or sector-shaped section for receiving and fixing a section of the first electrical conductor having a circular cross section or receiving and fixing a section of the second electrical conductor having a circular cross section or receiving and fixing both a section the first electrical conductor having a circular cross section and a section of the second electrical conductor having a circular cross section.

8. An electrical device in accordance with claim 4, wherein the cross section of the tunnel opening has a rectangular section for receiving and fixing a section of the electrical conductor having a rectangular cross section.

9. An electrical device in accordance with claim 4, wherein: the electrical conductor is a first electrical conductor and further comprising a second electrical conductor; at least one section of the second electrical conductor is arranged in the tunnel opening; the cross section of the tunnel opening has a rectangular section for receiving and fixing a section of the first electrical conductor having a rectangular cross section or for receiving and fixing a section of the second electrical conductor having a rectangular cross section or for receiving and fixing both a section of the first electrical conductor having a rectangular cross section and a section of the second electrical conductor having a rectangular cross section.

10. An electrical device in accordance with claim 1, wherein the cross section of the tunnel opening has an angular or curved shape.

11. An electrical device in accordance with claim 1, wherein the cross section of the tunnel opening has at least one tapering section.

12. An electrical device in accordance with claim 1, wherein the electrical device is a sheathed thermocouple.

13. An electrical device in accordance with claim 1, wherein the electrical device is an electrical heating device comprised of a heating cartridge or a coiled tube cartridge.

14. An electrical device in accordance with claim 13, further comprising an electrical heating element wound in at least some sections on an outer circumference of the insulator body and protruding in at least some sections into the tunnel opening.

15. An electrical device in accordance with claim 13, wherein the electrical heating device has an electrical heating element, which is arranged entirely in the tunnel opening.

16. An electrical device in accordance with claim 1, wherein the cross section of the tunnel opening has recesses for filling the tunnel opening with a powder comprising magnesium oxide powder.

17. An electrical device in accordance with claim 1, wherein the cross section of the tunnel opening is selected to be such that a ratio of a length of a circumferential line of the cross section to an area of the cross section is maximized for a given installation space.

18. An electrical device in accordance with claim 1, wherein first electrical conductor has a cross section that varies over a length thereof.

19. An electrical device in accordance with claim 17, wherein the cross section of the tunnel opening varies over a length thereof.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In the drawings:

[0032] FIG. 1a is a cross-sectional view showing an exemplary embodiment of an electrical device in the form of a first heating cartridge;

[0033] FIG. 1b is a perspective view showing the insulator body of the exemplary embodiment from FIG. 1a with a first conductor and a second conductor arranged thereon;

[0034] FIG. 1c is a cross-sectional view showing the insulator body with a first conductor and a second conductor arranged on the insulator body, taken at right angles in the cross section to the direction in which the insulator body extends;

[0035] FIG. 1d is a side view showing a variant of an inner structure for the exemplary embodiment from FIG. 1a with electrical conductors arranged thereon;

[0036] FIG. 1e is a cross-sectional view showing the insulator body from FIG. 1d, taken at right angles to the direction in which the insulator body extends;

[0037] FIG. 2a is a cross sectional view showing a first variant, taken through an insulator body at right angles to the direction in which the insulator body extends;

[0038] FIG. 2b is a cross sectional view showing a second variant, taken through an insulator body at right angles to the direction in which the insulator body extends;

[0039] FIG. 2c is a cross sectional view showing a third variant, taken through an insulator body at right angles to the direction in which the insulator body extends;

[0040] FIG. 2d is a cross sectional view showing a fourth variant, taken through an insulator body at right angles to the direction in which the insulator body extends;

[0041] FIG. 2e is a cross sectional view showing a fifth variant, taken through an insulator body at right angles to the direction in which the insulator body extends;

[0042] FIG. 2f is a cross sectional view showing a sixth variant, taken through an insulator body at right angles to the direction in which the insulator body extends;

[0043] FIG. 2g is a cross sectional view showing a seventh variant, taken through an insulator body at right angles to the direction in which the insulator body extends;

[0044] FIG. 2h is a cross sectional view showing an eighth variant, taken through an insulator body at right angles to the direction in which the insulator body extends;

[0045] FIG. 2i is a cross sectional view showing a ninth variant, taken through an insulator body at right angles to the direction in which the insulator body extends;

[0046] FIG. 2j is a cross sectional view showing a tenth variant, taken through an insulator body at right angles to the direction in which the insulator body extends;

[0047] FIG. 2k is a cross sectional view showing an eleventh variant, taken through an insulator body at right angles to the direction in which the insulator body extends;

[0048] FIG. 3a is a partially open perspective view showing an exemplary embodiment of an electrical device in the form of a second heating cartridge;

[0049] FIG. 3b is a cross sectional view taken through the exemplary embodiment from FIG. 3a at right angles to the direction in which it extends;

[0050] FIG. 3c is a cross sectional view through a first variant of the exemplary embodiment from FIG. 3a; and

[0051] FIG. 3d is a cross sectional view through a first variant of the exemplary embodiment from FIG. 3a.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0052] Referring to the drawings, FIG. 1a shows an electrical device 100 configured as a heating cartridge with a tubular metal sheath 110 with a bottom 111 and with an insulator body 120, which is arranged in the interior of the tubular metal sheath 110 and which is embedded in an electrically insulating material 150, e.g., MgO. Electrical supply lines 133, 134 are led through a plug 112 at the end of the tubular metal sheath 110 located opposite the bottom 111. As is also shown in FIGS. 1b and 1c, two tunnel-like openings 121, 122 pass through the insulator body 120. Respective sections 131a, 132a of a first electrical conductor 131, 132, which is formed by the current-carrying leads of supply lines 133, 134, are received in the tunnel-like openings 121, 122.

[0053] A second electrical conductor 140, the heating element, whose end sections 140a, 140b likewise pass through the tunnel-like openings 121, 122, extending parallel to the sections 131a, 132a of the first electrical conductors 131, 132 and are in electrical contact with these, for example, by pressure contacting, is wound on the insulator body 120 on the outside.

[0054] As is clearly shown in FIGS. 1b and 1c, the cross section of the tunnel-like openings 121, 122 is essentially triangular, namely, it has the cross section of a triangle with rounded tips, the triangle being always oriented such that one tip points outwards in the radial direction of the insulator body 120. The end sections 140a, 140b of the heating elements are arranged in the area of these tips. The sections 131a, 132a of the current-carrying leads, which have a larger cross section than the heating element, are in contact with the base. The cross section of the tunnel-like openings 121, 122 thus predefines the positioning of the sections of the first electrical conductor 131, 132 and of the second electrical conductor 140, which are received in the tunnel-like opening 121, 122, which leads to improved process reliability of the pressure contacting.

[0055] When viewed together with FIG. 1e, FIG. 1d shows a variant of an inner structure, which variant is especially suitable for high-current applications, for an electrical heating cartridge with an insulator body 160 with tunnel-like openings 161, 162, into which the respective sections 171a, 172a of a first electrical conductor 171, 172, which is formed by the terminal studs of the heating cartridge, are inserted and through which they pass. The problem of accommodating terminal studs with a maximum cross section in the space available for installation often arises in these applications. This is made possible here by the tunnel-like openings 161, 162 having a circle segment-shaped cross section, i.e., a cross section deviating from the circular shape. The electrical heating element 173 is wound on the outer circumference of the insulator body 160 and is connected at contact points 174, 175 to the terminal studs.

[0056] FIGS. 2a through 2k show a respective cross section each through insulator bodies 300, 310, 320, 330, 340, 350, 360, 370, 380, 390, 400 with tunnel-like openings 301, 302, 311, 312, 321, 322, 331, 332, 341, 342, 343, 344, 351, 352, 353, 354, 361, 362, 371, 372, 381, 382, 391, 392, 401, 402, 403 and 404, in which sections of conductors 305, 306, 315, 316, 325, 326, 335, 336, 337, 345, 346, 347, 355, 356, 365, 366, 375, 376, 377, 385, 386, 395, 396, 405, 406, 407, 408 are received, in order to illustrate the extremely flexible applicability of the present invention in a plurality of concrete installation situations. For example, such configurations may be used to use U-shaped, stretched heating wires with maximum cross sections.

[0057] It should be noted in advance that combinations of tunnel-like openings 301, 302, 311, 312, 321, 322, 331, 332, 341, 342, 343, 344, 351, 352, 353, 354, 361, 362, 371, 372, 381, 382, 391, 392, 401, 402, 403 and 404 shown in the different FIGS. 2a through 2k are, of course, also possible.

[0058] In particular, asymmetric combinations are, of course, possible, even though the far overwhelming majority of the examples shown show pairs of symmetrically configured tunnel-like openings 301, 302, 311, 312, 321, 322, 331, 332, 341, 342, 343, 344, 351, 352, 353, 354, 361, 362, 371, 372, 381, 382, 391, 392, 401, 402, 403 and 404.

[0059] In the embodiment according to FIG. 2a, the essentially T-shaped cross-sectional geometry of the tunnel-like openings 301, 302 is adapted to the cross-sectional geometry of the respective conductor sections 305, 306, which are each configured as flat strips and are received in the tunnel-like openings 301, 302. The conductors 306 are likewise arranged and fixed here in a rectangular section of the tunnel-like openings 301, 302.

[0060] The cross section of the tunnel-like openings 311, 312 is always circle segment-shaped in the embodiment according to FIG. 2b, as a result of which a very large available cross section can be provided.

[0061] The tunnel-like openings 321, 322 have a curved, kidney-shaped cross section each in the embodiment according to FIG. 2c.

[0062] In the embodiment according to FIG. 2d, the tunnel-like openings 331, 332 have a cross section with an angular basic shape with two rectangular sections directed at right angles to one another, in which respective conductor sections 335, 337 configured as flat strips are received and fixed. In addition, a circle segment-shaped section is present, which receives and fixes the electrical conductor 336. For example, two heating conductors 335, 337 of a switchable heating cartridge can be reliably contacted in this manner with a connection wire 336 in a reliable process.

[0063] In addition to the tunnel-like openings 341, 342, which are circle segment-shaped and thus have a cross section tapering in the radial direction inwards from the outside and in which sections of a first conductor 345 and sections of a second conductor 346 each are connected to one another, two tunnel-like openings 343, 344, which are configured as holes with circular cross section and in which the respective thermocouple wire legs of a thermocouple are received as respective conductors 347, are present in the embodiment according to FIG. 2e.

[0064] The embodiment according to FIG. 2f is especially well suited for another variant of a switchable heating cartridge. Respective first sections of a first conductor 355 and sections of a second conductor 356 are connected here to one another in four tunnel-like openings 351, 352, 353, 354, which have a sector-shaped cross section, which thus tapers in the radial direction from the outside to the inside.

[0065] The embodiment according to FIG. 2f is characterized in that the cross sections of the tunnel-like openings 361, 362 allow for the connection of an electrical conductor 365 with a large cross section, which is configured as a flat strip, to a conductor 366, whose cross section is much smaller and is circular. Accurate positioning of the conductors 365, 366 relative to one another and hence a much better reproducibility of their electrical contacting with one another and of their properties are achieved in case of such configurations as well due to a circle segment-shaped section of the cross section of the tunnel-like openings 361, 362, in which the respective conductor 366 is received and fixed.

[0066] The embodiment according to FIG. 2g has a tunnel-like opening 371, whose cross section resembles the cross section parallel to the central axis through a truncated cone with rounded corners and tapers radially outwards. Conductors 375, 376 are brought into connection with one another in this opening 371. In addition, yet another tunnel-like opening 372 with circular cross section is present, into which, e.g., a thermocouple can be inserted as a conductor 377.

[0067] The embodiments according to FIGS. 2i and 2j show respective tunnel-like openings 381, 382 as well as 391, 392 with oval cross section. The longitudinal axis of the oval is always adapted to the cross sections of the respective electrical conductors 385, 385 as well as 395, 396.

[0068] The embodiment according to FIG. 2k is an asymmetric variant of the embodiment according to FIG. 2f. Respective first sections of a first conductor 405 and sections of a second conductor 406 are connected to one another here in two tunnel-like openings 401, 402 whose cross section is sector-shaped and hence tapers in the radial direction from the outside to the inside, while respective first sections of a first conductor 407 and sections of a seconded conductor 408 are connected to one another in two additional tunnel-like openings 403, 404, whose cross section is sector-shaped and hence tapers in the radial direction from the outside to the inside, wherein the size of the sectors is adapted to the cross section of the conductors received in them.

[0069] FIGS. 3a and 3b show an exemplary embodiment of an electrical device in the form of a second heating cartridge 200 with a tubular metal sheath 210, which has an essentially rectangular outer contour.

[0070] An insulator body 220 with a tunnel-like opening 221, which has the shape of a rectangle with rounded corners here, is arranged in the interior of the tubular metal sheath. Sections of a first conductor 231 and of a second conductor 232, which are respective terminal studs for power supply, and between which an electrical heating element 240, typically a coiled heating wire embedded in an insulator, not shown here, extends, are inserted each from one side in the tunnel-like opening.

[0071] Not only is it ensured by the rectangular configuration of the cross section of the tunnel-like opening, which configuration consequently deviates from the circular shape, that a large cross section is available for the terminal stud, so that an unheated area is formed and efficient working with high currents is facilitated, but a greater heating wire length can also be achieved per turn and hence a higher heat output due to this measure.

[0072] FIG. 3c shows a cross section through a first variant of the exemplary embodiment from FIG. 3a, as it may be used, for example, for an electrical heating device, in which both terminal studs are arranged on the same side. An insulator body 251 is correspondingly received in the tubular metal sheath 250, and the tunnel-like opening 252 in the insulator body, which opening has again an essentially rectangular cross section and sections of terminal studs are received in it, extends in a U-shaped configuration and has oval heating wire coils 254.

[0073] In the variant according to FIG. 3d, the tubular metal sheath 260 has a circular cross section. The insulator body 261 arranged in the interior of the tubular metal sheath 260 has a tunnel-like opening 262, whose cross section has a square basic shape 262a, which is widened at the corners of the square by respective sector-shaped sections 262b, 262c, 262d, 262e. A boundary line between the square basic shape 262a and the sector-shaped sections 262b-262e is shown by dashed lines for illustration.

[0074] A section of a first conductor and the heating wire coil 263 are arranged in the interior of the tunnel-like opening 262 in the area of the square basic shape 262a. The sector-shaped sections 262b-262e support the filling of the tunnel-like opening 262 with an electrically insulating material having good heat conductivity, e.g., magnesium oxide.

[0075] While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.

APPENDIX

List of Reference Numbers

[0076] 100, 200 Electrical device [0077] 110, 210, 250, 260 Tubular metal sheath [0078] 111 Bottom [0079] 112 Plug [0080] 120, 160, 220, 251, 261 Insulator body [0081] 121, 122, 161, 162, 221, 252, 262 Tunnel-like opening [0082] 131, 132, 171, 172, 231, 263 First electrical conductor [0083] 131a, 132a, 171a, 172a Section [0084] 133, 134 Supply line [0085] 140, 232 Second electrical conductor [0086] 140a, 140b Section [0087] 150 Electrically insulating material [0088] 173, 240 Electrical heating element [0089] 174, 175 Contact point [0090] 254, 263 Heating wire coil [0091] 262a Square basic shape [0092] 262b, 262c, 262d, 262e Sector-shaped section [0093] 300, 310, 320, 330, 340, 350, 360, 370, 380, 390, 400 Insulator body [0094] 301, 302, 311, 312, 321, 322, 331, 332, 341, 342, 343, 344, 351, 352, 353, 354, 361, 362, 371, 372, 381, 382, 391, 392, 401, 402, 403, 404 Tunnel-like opening [0095] 305, 306, 315, 316, 325, 326, 335, 336, 337, 345, 346, 347, 355, 356, 365, 366, 375, 376, 377, 385, 386, 395, 396, 405, 406, 407, 408 Conductor