GB2109642A

GB2109642A - Excitation current input device for an alternating current generator

Info

Publication number: GB2109642A
Application number: GB08227247A
Authority: GB
Inventors: Gerhard Peluger
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 1981-09-26
Filing date: 1982-09-24
Publication date: 1983-06-02
Also published as: DE3138453A1; GB2109642B; FR2513827A1; IT8223016V0

Abstract

An excitation current input device for an alternating current generator has a semi-conductor voltage regulator (3), a brush holder (4) for guiding two slip ring brushes (1, 2) and an intermediate piece (16) made from insulating material, which is placed between the brush holder and the housing of the regulator (3). The intermediate piece (16) contains inserted current conductors which receive the plug pins (12, 13) protruding from the underside of the housing of the regulator. <IMAGE>

Description

SPECIFICATION Excitation current input device for an alternating current generator The invention concerns an excitation current input device for an alternating current generator, with a semi-conductor voltage regulator and with a brush holder which serves to guide two brushes, and which has a flat base joined to two guide sleeves for the brushes which are positioned parallel to each other and on one side of the base.

The invention is intended to provide an arrangement which allows a completely encapsulated regulator, preferably inside a housing which is similar to a transistcr, in an interchangeable dust-proof construction, to be fixed to the brush holder so that the connections to the brush holder can remain unchanged.

The invention consists in an excitation current input device for an alternating current generator, comprising a semi-conductor voltage regulator, a brush holder for guiding two brushes, the brush holder having a flat base to which are connected two guide sleeves for the brushes which lie parallel to each other and at one side of the base, an intermediate piece which is made from insulating material and which sits on the upper side of the base of the brush holder and supports the housing of the regulator, and current conductors which are disposed in recesses in the under-side of the intermediate piece and which accept plug pins protruding from the under-side of the regulator housing. The current conductors being pushed over the plug pins and fixed to them and passing through the base.

The invention is further described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a part-sectioned front view of an excitation current input device according to the invention, in which a brush holder and an intermediate piece of insulation material combined, as a component in a semi-conductor voltage regulator, Figure 2 is a side view, illustrating the connectors for the brushes seated in the brushholder, Figure 3 is a view from below of the intermediate piece, prior to attachment to the brush holder, and Figure 4 is a section through the intermediate piece, taken along the line IV--IV as shown in Figure 3.

The device shown, serves to supply the excitation current to the rotating excitation coil of an alternating current generator (not shown), by means of two slip-ring brushes 1 and 2, set at a distance from each other, the excitation current being determined by means of a regulator installed in a transistor-like housing 3, such that the direct current at the output of a rectifier set of the generator is maintained at least approximately constant in order to charge a starter battery (also not shown) despite widely fluctuating speeds which occur during the operation of a vehicie, particuiarly a utility vehicle.

In order to guide the brushes 1 and 2 in a longitudinal direction for engagement with respective slip rings of the generator two guide sleeves which are rectangular in section, the other details of which are not shown, are formed in the brush holder 4 which is moulded from Duroplast (KERIPOL), and extend parallel to the base 5., of the brush holder. As can be seen in more detail in Figure 2, the brush holder 4 has a rib 6 which protrudes from the side and to which two terminal lugs 7 and 8 for the brush cables 9 and 10, are riveted.

The regulator 3, has a pressure- and moistureproof metal housing, into the base-plate 11 of which two plug pins 12 and 13 are fixed and insulated. Since the metal housing of the regulator 3 carries voltage, it is covered with a thin-walled plastic hood 14, which has two narrow edges opposite each other, which catch under the base-plate 11 by means of a bulbous lip 1 5, and hold the hood fast. In order to adapt the brush holder 4, which can also be used on other regulators and types of generator, an intermediate piece 1 6 moulded from the plastics, is provided which is shown in Figure 3 and whose contour substantially overlies the contour of the base 5, but is rather narrower in its central region.The base-plate 11 of the regulator 3 is clamped against the upper side 1 9 of the intermediate piece 1 6 by means of rivets 20, with the interposition of a thicker cooling plate 17, and a thinner cooling plate 18, the cooling plates serving as a heat sink. In the under-side of the intermediate piece 16, as shown in Figure 3, two additional recesses 23 and 24, are provided between the circular recesses 22 for the rivet heads 21 on the rivets 20, viz. a square recess 23 and an L-shaped recess 24. A current conductor 25 is inserted into the square recess 23, and this is shown in section in Figure 4; it has a central punched hole 26 with a collar-shaped pushedthrough edge 27.The current conductor 25 is made from thin chrome-nickel steel plate and has a punched-out terminal tab 28, which stands at right-angles to the under-side of the intermediate piece 16, and which is contracted on being combined with the brush holder, and is then locked into an incision in the terminal lug 7 (not shown in detail) in the manner indicated in Figure 1, and is soldered in position. The plug pin 12, locks into the central punched hole 26 in the current conductor 25, the plug pin consisting of the same material as the current conductor and it can therefore be welded to the collar 27, in an inert gas atmosphere.

The other L-shaped recess 24 contains a second current conductor 30, which also has a punched hole 31 for insertion of the second plug pin 13 of the regulator 3, and an incised rightangled upstanding end-section 32, which is shown in sideview in Figure 4 and which is passed through a perpendicular slit 33 in the base 5 of the brush holder 4 during assembly. The protruding end section contains a punched hole 34. This end section is then bent outwards, as shown in Figure 1 on the right, so as to underlie the fixing holes 35 and 36 in the intermediate piece 1 6 and the base 5 respectively, and can then be fastened to the body of the generator with a fixing screw (not shown).

As is shown in more detail in Figure 4, the thin cooling plate 1 8 is cut to give a contact tab 38, which is passed through an opening 39 in the intermediate piece and an opening in the base 5 and then its free end is inserted into the terminal lug 7 and soldered in position. Therefore, the metal housing of the regulator 3 has a D+ potential applied to it through this contact tab 38, the D+ potential being the positive potential of a rectifier diode set of the generator additional to the output rectifier set.

The current conductor 25, inserted into the recess 23, has a cut-out terminal tab 28. This is inserted between two bowed ends 40 of the second terminal lug 8, and is soldered in position.

Claims

1. An excitation current input device for an alternating current generator, comprising a semiconductor voltage regulator, a brush holder for guiding two brushes, the brush holder having a flat base to which are connected two guide sleeves for the brushes which lie parallel to each other and at one side of the base, an intermediate piece which is made from insulating material and which sits on the upper side of the base of the brush holder and supports the housing of the regulator, and current conductors which are disposed in recesses in the underside of the intermediate piece and which accept plug pins protruding from the under-side of the regulator housing, the current conductors being pushed over the plug pins and fixed to them and passing through the base.

2. A device as claimed in claim 1, in which the plug pins engage into punched-out holes in the current conductors.

3. A device as claimed in claim 2, in which the poles in the conductors have drawn-out portions.

4. A device as claimed in claim 2 or 3 in which the plug pins are connected to the current conductors by inert gas fusion welding.

5. A device as claimed in any of claims 1 to 4, in which the current conductors are made from chrome-nickel steel.

6. A device as claimed in any of claims 1 to 5, in which a cooling plate is inserted between the bottom side of the regulator and the upper side of the intermediate piece and contains at least one punched-out aperture to allow contact-free passage of the two plug pins of the regulator, from the edge of which aperture an elongated contact tab is cut and bent out of the plane of the cooling plate.

7. A device as claimed in any of claims 1 to 6, in which an angled current conductor is connected to one of the plug pins and passes through the intermediate piece and the base of the brush holder, in which the angled current conductor is bent outwards at its end sections which protrude from the base and which contain a hole which aligns with a hole in the base which takes a metal fixing means, particulariy a screw or a rivet.

8. An excitation current input device for an alternating current generator, constructed and arranged substantially as herein described with reference to and as illustrated in the accompanying drawings.