Power resistor

Abstract

A power resistor comprises a tubular housing composed of metal and a resistor element received therein, wherein the housing has four side walls that extend along a longitudinal axis of the housing between two ends and define a rectangular cross-section. The housing comprises four edges of the four side walls at at least one of the two ends. Two of the four side walls have a respective incision at their edges for introducing a fastening element and the two other side walls have a respective clearance in alignment with the oppositely disposed incision to facilitate a placement of a tool at a fastening element introduced into the respective incision.

Claims

1. A power resistor comprising a housing that is tubular, the housing composed of metal and having a resistor element received therein, wherein the housing has four side walls that extend along a longitudinal axis of the housing between two ends and that define a rectangular cross-section, with a first side wall and a third side wall being disposed opposite one another and with a second side wall and a fourth side wall being disposed opposite one another, wherein the housing comprises at least one of the two ends, the at least one of the two ends comprising: a first edge of the first side wall that has a first incision for introducing a fastening element, a second edge of the second side wall that has a second incision for introducing a fastening element, a third edge of the third side wall, and a fourth edge of the fourth side wall; the third side wall having a first clearance at least substantially in alignment with the first incision and the fourth side wall having a second clearance at least substantially in alignment with the second incision to facilitate a placement of a tool at a fastening element introduced into at least one of the first incision or the second incision; wherein the first edge and the second edge extend within an orthogonal plane to the longitudinal axis of the housing; wherein the third edge extends at a slant with respect to said orthogonal plane to form the first clearance; and wherein the fourth edge extends at a slant with respect to said orthogonal plane to form the second clearance.

2. The power resistor in accordance with claim 1, wherein the third edge is at least sectionally set back relative to the first edge along the longitudinal axis of the housing to form the first clearance; and wherein the fourth edge is at least sectionally set back relative to the second edge along the longitudinal axis of the housing to form the second clearance.

3. The power resistor in accordance with claim 1, wherein the third edge and the fourth edge extend within a common cutting plane that extends at a slant to said orthogonal plane.

4. The power resistor in accordance with claim 1, wherein the first incision and the second incision are formed as elongate and extend along the longitudinal axis of the housing.

5. The power resistor in accordance with claim 4, wherein at least one of the first incision is arranged off center at the first side wall and the second incision is arranged off center at the second side wall.

6. The power resistor in accordance with claim 1, wherein the resistor element has connector elements that project from the housing.

7. The power resistor in accordance with claim 1, wherein the resistor element is held in an electrically insulating carrier body within the housing.

8. The A power resistor in accordance with claim 1, wherein the housing is formed from aluminum.

9. A power resistor comprising a housing that is tubular, the housing composed of metal and having a resistor element received therein, wherein the housing has four side walls that extend along a longitudinal axis of the housing between two ends and that define a rectangular cross-section, with a first side wall and a third side wall being disposed opposite one another and with a second side wall and a fourth side wall being disposed opposite one another, wherein the housing comprises at least one of the two ends, the at least one of the two ends comprising: a first edge of the first side wall that has a first incision for introducing a fastening element, a second edge of the second side wall that has a second incision for introducing a fastening element, a third edge of the third side wall, and a fourth edge of the fourth side wall; the third side wall having a first clearance at least substantially in alignment with the first incision and the fourth side wall having a second clearance at least substantially in alignment with the second incision to facilitate a placement of a tool at a fastening element introduced into at least one of the first incision or the second incision; wherein the third side wall has an opening to form the first clearance and wherein the fourth side wall has an opening to form the second clearance, and wherein the first edge, the second edge, the third edge, and the fourth edge extend within a common orthogonal plane to the longitudinal axis of the housing.

10. The power resistor in accordance with claim 9, wherein the opening of the third side wall is formed by a peripherally closed passage, and wherein the opening of the fourth side wall is formed by a peripherally closed passage.

11. A power resistor comprising a housing that is tubular, the housing composed of metal and having a resistor element received therein, wherein the housing has four side walls that extend along a longitudinal axis of the housing between two ends and that define a rectangular cross-section, with a first side wall and a third side wall being disposed opposite one another and with a second side wall and a fourth side wall being disposed opposite one another, wherein the housing comprises at least one of the two ends, the at least one of the two ends comprising: a first edge of the first side wall that has a first incision for introducing a fastening element, a second edge of the second side wall that has a second incision for introducing a fastening element, a third edge of the third side wall, and a fourth edge of the fourth side wall; the third side wall having a first clearance at least substantially in alignment with the first incision and the fourth side wall having a second clearance at least substantially in alignment with the second incision to facilitate a placement of a tool at a fastening element introduced into at least one of the first incision or the second incision; wherein the third side wall has an opening to form the first clearance and wherein the fourth side wall has an opening to form the second clearance, wherein the opening of the third side wall is formed by a peripherally closed passage and wherein the opening of the fourth side wall is formed by a peripherally closed passage.

12. A power resistor comprising a housing that is tubular, the housing composed of metal and having a resistor element received therein, wherein the housing has four side walls that extend along a longitudinal axis of the housing between two ends and that define a rectangular cross-section, with a first side wall and a third side wall being disposed opposite one another and with a second side wall and a fourth side wall being disposed opposite one another, wherein the housing comprises at least one of the two ends, the at least one of the two ends comprising: a first edge of the first side wall that has a first incision for introducing a fastening element, a second edge of the second side wall that has a second incision for introducing a fastening element, a third edge of the third side wall, and a fourth edge of the fourth side wall; the third side wall having a first clearance at least substantially in alignment with the first incision and the fourth side wall having a second clearance at least substantially in alignment with the second incision to facilitate a placement of a tool at a fastening element introduced into at least one of the first incision or the second incision; wherein the first clearance comprises a slanted portion of the third wall opposite the first incision, and wherein the second clearance comprises a slanted portion of the fourth wall opposite the second incision.

13. A power resistor comprising a housing that is tubular, the housing composed of metal and having a resistor element received therein, wherein the housing has four side walls that extend along a longitudinal axis of the housing between two ends and that define a rectangular cross-section, with a first side wall and a third side wall being disposed opposite one another and with a second side wall and a fourth side wall being disposed opposite one another, wherein the housing comprises at least one of the two ends, the at least one of the two ends comprising: a first edge of the first side wall that has a first incision for introducing a fastening element, a second edge of the second side wall that has a second incision for introducing a fastening element, a third edge of the third side wall, and a fourth edge of the fourth side wall; the third side wall having a first clearance at least substantially in alignment with the first incision and the fourth side wall having a second clearance at least substantially in alignment with the second incision to facilitate a placement of a tool at a fastening element introduced into one of the first incision and the second incision; wherein the first clearance comprises a hole in the third wall opposite the first incision, and wherein the second clearance comprises a hole in the fourth wall opposite the second incision.

Description

(1) The invention will be described in the following purely by way of example with, reference to the drawings. Elements which are the same or of the same kind are marked by the same reference numerals therein.

(2) FIG. 1 shows a perspective view of a first embodiment of a power resistor in accordance with the invention in a horizontal alignment;

(3) FIG. 2 shows a perspective view of a first embodiment of a power resistor in accordance with the invention in a vertical alignment,

(4) FIG. 3 shows a perspective view of a second embodiment of a power resistor in accordance with the invention in a horizontal alignment;

(5) FIG. 4 shows a perspective view of a second embodiment of a power resistor in accordance with the invention in a vertical alignment; and

(6) FIG. 5 shows a perspective view of a power resistor of a known construction in a vertical (FIG. 5a) and a horizontal (FIG. 5b) alignment.

(7) A first embodiment of a power resistor 10 in accordance with the invention is shown in FIG. 1 and in FIG. 2, wherein the power resistor 10 is shown in a horizontal alignment in FIG. 1 and in a vertical alignment in FIG. 2. The power resistor 10 comprises a tubular housing 12 of aluminum in whose interior a resistor element, not shown, is arranged. The housing 12 extends along a longitudinal axis L.

(8) The resistor element in the interior of the housing 12 extends strand-like along the longitudinal axis L and can, for example, be configured as a glass fiber cord that is wound around by resistor wire. The resistor element is surrounded by a carrier body of heat conductive insulation material (not shown) for the electrical insulation and dissipation of the resistor element. The housing 12 is closed by termination walls 14 at the axial front sides.

(9) Core end sleeves, not shown, that serve for the connection of connector cables that project from the housing 12 at both ends of the housing 12 (cf. the connector cables 60 shown in FIG. 5) can be attached to both ends of the resistor element. The termination walls 14 have leadthroughs, not shown, for this purpose.

(10) The housing 12 has four side walls that define an elongate rectangular cross-section, with a first side wall 20 and a third side wall 40 being disposed opposite one another and with a second side wall 30 and a fourth side wall 50 being disposed opposite one another. The side walls form straight-line edges at their ends shown in FIG. 1 and FIG. 2, with a first edge 22 terminating the first side wall 20, a second edge 32 terminating the second side all 30, a third edge 42 terminating the third side wall 40, and a fourth edge 52 terminating the fourth side wall 50.

(11) The four edges each converge on one another pairwise at four corner points, with a first corner point 26 being formed by the convergence of the first edge 22 with the second edge 32, a second corner point 36 being formed by the convergence of the second edge 32 with the third edge 42, a third corner point 46 being formed by the convergence of the third edge 42 with the fourth edge 52, and a fourth corner point 56 being formed by the convergence of the fourth edge 52 with the first edge 22.

(12) The first edge 22 of the first side wall 20 has a first incision 24 for introducing a fastening elementfor example a screwthat extends along the longitudinal axis L of the housing 12 and that hereby interrupts the first edge 22. The second edge 32 of the second side wall 30 equally has a second incision 34 for introducing a fastening element that extends along the longitudinal axis L of the housing 12 and that hereby interrupts the second edge 32. The incisions 24 and 34 are open toward their respective edges 22 and 32 and can be round or angled at their oppositely disposed ends, with combined forms such as shown in FIG. 1 and FIG. 2 also being possible.

(13) The incisions 24 and 34 can be formed by milling, for example. The incisions 24 and 34 can be arranged centrally or offset from the center with respect to the corresponding edge 22 and 32 respectively. A plurality of incisions (attached centrally or offset from the center) can in particular also be provided at the respective edge 22 and 32. Different possibilities for positioning the fastening element would thus result in dependence on the demands of the spatial arrangement of the power resistor.

(14) The power resistor 10 can first be brought into the provided position of a substrate for fastening to the substrate and can then be fixed by the fastening element introduced into one of the incisions 24 or 34. It is alternatively also possible first to align the fastening element in a first step and to lightly fix it in the substrate at a provided position. In a second step, the power resistor 10 can be pushed through the opening of one of the incisions 24 or 34 applied to the respective edge 22 or 32 to the fastening element at the provided position at the substrate to fix it there by the fastening element.

(15) To provide sufficient free space for the required placement of a tool at a fastening element introduced into the first incision 24 or into the second incision 34 for such a fastening of the power resistor 10, the third side wall 40 has a first clearance 47 and the fourth side wall 50 has a second clearance 57. The first clearance 47 is here provided along an axis A1 that extends perpendicular to the plane of extent of the first side wall 20 in alignment with the first incision 24. The second clearance 57 is accordingly provided in alignment with the second incision 34 along an axis A2 that extends perpendicular to the plane of extent of the second side wall 30. The first clearance 47 is here formed in that the third edge 42 extends at a slant with respect to an orthogonal plane to the longitudinal axis L of the housing 12 and is hereby increasingly set back along the longitudinal axis L of the housing 12 relative to the first edge 22 starting from the second corner point 36. The second clearance 57 is formed in that the fourth edge 52 likewise extends at a slant with respect to said orthogonal plane to the longitudinal axis L of the housing 12 and is hereby increasingly set back along the longitudinal axis L of the housing 12 relative to the second edge 32 starting from the fourth corner point 56.

(16) This embodiment can be manufactured in a simple manner by applying only two cuts to a rectangular tube, with a fast cut cutting the rectangular tube along a first cutting plane that corresponds to said orthogonal plane to the longitudinal axis L of the housing 12 so that the first edge 22 and the second edge 32 are defined and formed. The first clearance 47 and the second clearance 57 are formed by a second cut that starts at the second corner point 36 and at the fourth corner point 56 of the housing 12 and takes place along a cutting plane that extends at a slant to said orthogonal plane and set back in the direction of extent of the housing 12. The second cutting plane forms the third edge 42 and the fourth edge 52 respectively by its cut with the third side wall 40 or the fourth side wall 50 respectively, said third and fourth edges forming the first clearance 47 and the second clearance 57 respectively by their slanted extent and by the corresponding setting back relative to the first edge 22 or to the second edge 32 respectively.

(17) As a result, the cutting procedure forms four edges 22, 32, 42, and 52 of the housing 12 with little cutting loss, with a respective two edges 22 and 32 and 42 and 52 respectively extending in common planes that include an angle with one another. The first incision 24 and the second incision 34 can be reached without obstruction for a straight-line access from the respective oppositely disposed side wall 40 or 50 respectively due to a tilt of the two planes with respect to one another and due to the first and second clearances 47, 57 thus formed. Possible accesses for placing a tool to a fastening element introduced into the first incision 24 or into the second incision 34 are indicated by the axes A1 and A2 shown by dashed lines in FIG. 1 and FIG. 2.

(18) The power resistor 10 can now selectively be fastened to a substrate in a horizontal alignment on an introduction of the fastening element into the first incision 24 or in a vertical alignment on an introduction of the fastening element into the second incision 34 with the free access to the first incision 24 and to the second incision 34.

(19) In contrast, with power resistors of a known configuration, such as FIG. 5 shows, two different embodiments are provided that can only be installed in one respective alignmentvertical or horizontal. This is due to a cutting process that enables the formation of only one clearance with respect to a first incision 34for a horizontal alignmentor with respect to a second incision 34for a vertical alignment. The manufacturing process for a housing 12 of known power resistors in accordance with FIG. 5 is based on only one slanted cut, wherein in the embodiment in accordance with FIG. 5a, the long edges of the elongate rectangular cross-section of the housing 12 extend at a slant to an orthogonal plane with respect to the longitudinal axis L of the housing 12 and, in the embodiment in accordance with FIG. 5b, the short edges of the elongate rectangular cross-section of the housing 12 extend at a slant to an orthogonal plane with respect to the longitudinal axis L of the housing 12. The housings 12 can be manufactured for power resistors of a known configuration without cutting loss due to the restriction of the cutting process to one single cut. In turn, however, these power resistors have restrictions in functionality, in particular with respect to the fastening to the deployment site.

(20) A second embodiment of a power resistor 10 in accordance with the invention is shown in FIG. 3 and in FIG. 4, wherein the power resistor 10 is shown in a horizontal alignment in FIG. 3 and in a vertical alignment in FIG. 4. The power resistor 10 of the second embodiment only differs from the power resistor 10 of the first embodiment by the shape of the clearances so that reference is made to the above explanations for a description of the inner design.

(21) As can be seen from FIG. 3 and FIG. 4, the four edges 22, 32, 42, and 52 of the housing body 12 extend in a common plane that corresponds to an orthogonal plane of the housing 12 with respect to its longitudinal axis L. The formation of the edges 22, 32, 42, and 52 here takes place by a single cut perpendicular to the side walls 20, 30, 40, and 50 of the rectangular tube.

(22) In the second embodiment, the first clearance and the second clearance are formed in that the third side wall 40 and the fourth side wall 50 have openings 48 and 58 respectively through which a tool can be led to fix a fastening element introduced into the first incision 24 or into the second incision 34. A first opening 48 is arranged in the third side wall 40 for this purpose such that it is disposed opposite the incision 24 in the first side wall 20. A second opening 58 is equally disposed in the fourth side wall 50 opposite the incision 34 in the second side wall 30. If a plurality of incisions are provided (centrally or offset from the center of an edge) per side wall, a plurality of openings or a sufficiently large opening are/is accordingly formed that are/is disposed opposite the respective incisions.

(23) The openings 48 and 58 can, for example, be circular and can in particular be formed by a bore, whereby a simple and inexpensive manufacture results. To facilitate the fastening of the power resistor and in particular the guidance of a tool through the openings 48 and 58 respectively, the openings 48 and 58 should here have a diameter that is larger than the width of the respective incision 24 and 34 (viewed transversely to the longitudinal axis L). The housing 12 of the second embodiment can thus be manufactured without cutting loss like the housing 12 of the previous power resistors (see FIG. 5). The manufacture, however, requires a tool change for this purpose to apply the openings 48 and 58 in the side walls 40 and 50.

(24) The openings 48 and 58 prevent an obstruction of the first incision 24 and of the second incision 34 by the respective oppositely disposed side wall 40 and 50 respectively and enable the simultaneous straight-line access to both incisions 24, 34. Possible accesses for a straight-line placement of a tool to a fastening element introduced into the first incision 24 or into the second incision 34 are indicated by the axes A1 and A2 shown by dashed lines in FIG. 3 and FIG. 4.

(25) The power resistor 10 can now selectively be fastened in a simple manner in the horizontal alignment on an introduction of the fastening element into the first incision 24 or in the vertical alignment on an introduction of the fastening element into the second incision 34.

(26) It is understood that the embodiment of a longitudinal end of the housing 12 explained with reference to FIGS. 1 to 4 can analogously also be provided at the other longitudinal end of the housing 12, with the respective incision 24, 34 being provided at the same side wall 20 or 30.

REFERENCE NUMERAL LIST

(27) 10 power resistor 12 housing 14 termination wall 20 first side wall 22 first edge 24 first incision 26 first corner point 30 second side wall 32 second edge 34 second incision 36 second corner point 40 third side wall 42 third edge 46 third corner point 47 first clearance 48 first opening 50 fourth side wall 52 fourth edge 56 fourth corner point 57 second clearance 58 second opening 60 connector cable A1 axis through 24 A2 axis through 34 L longitudinal axis