DE1952416A1 - AC generator directly coupled to an internal combustion engine - Google Patents

Description

Patent attorneys,

Dipl.- Ing. Ü . Beetz u.
Dipl.-Ing. Lamprecht 81 -15.025P (15.026H) 10/17/1969

Munich 22, Steliwdorfttr. 10

HITACHI, LTD., Tokyo ^ Japan)

Alternating current generator tied directly to an internal combustion engine

The invention relates to a brushless one AC generator stranded with a rotor coupled directly to the crankshaft of a vehicle engine is.

The alternator housed in a vehicle is usually powered by the machine that drives the vehicle. Ordinary vehicles use an arrangement in which the crankshaft is a Machine extends outside of the machine block and on the part of the crankshaft that extends outwards Äietaenscheibe is mounted so that the generator together

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with a cooling valve gate and the like. By means of a belt is driven. Meanwhile, from the standpoint of miniaturization of the machine, this belt drive system is: Rail units are extremely disadvantageous and, moreover, the belt drive type is impractical as an alternator type for small motor vehicles such as B. a motorcycle. Under these circumstances it was on a motorcycle a flywheel igniter or a starter dynamo is used, both of which are actually from a maintenance point of view, Inspection and service life are disadvantageous because the flywheel igniter generally does not produce a great deal of power and the starter dynamo included brushes and a commutator.

To eliminate these drawbacks, a lorm of the Drive developed using an alternator Coupled directly to the crankshaft of a machine, and brushless alternators were also used proposed to solve the problem of maintenance due to brushes and other rushes. Examples of it were in U.S. Patents 3,215,877 and 2,928,963, but both still suffered serious disadvantages flawed in structure when considering the point of temperature rise in the alternator. Initially, the anchor core and were in the former in the pail the peld core exposed to heat from the engine as it was mounted on the engine block, and also the pitched ! Temperature of the armature and PcL windings to the extreme high increase due to the generation of heat in these windings. In the second pail the anchor core and the Peldkern of the alternator held on the back of the machine, so that the direct exposure to heat Due to the heat generated by the machine was not great,

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However, since this alternator was mounted between the engine block and the gearbox, the structure was not suitable for the dissipation of the current in the armature coil and in the field coil self-generated heat. In other words, apart from the fact that the gearbox usually was mechanically coupled to the machine block and so under the action of the heat of the machine was standing, a significant increase in temperature due to the heat generated by the gears and the lubricating oil, and therefore the heat release, particularly the release of the in the an the inside-mounted field coil generated heat difficultly. Hence there was a considerable rise in temperature unavoidable in this alternator.

In this type of alternator, the effect of temperature rise has a deleterious influence on the electrical insulation of the two coils and leads to a decrease in the electrical power Reason for an increase in electrical resistance. In particular, a lower current flow reduces due to an increase in the resistance of the field coil, the intensity of a generated magnetic field and becomes a Main factor in the decrease in electrical output power.

It is therefore a main object of the invention to provide a Brushless alternator directly coupled to a machine to create its temperature rise is low and generates a relatively large electrical output power despite its compact dimensions. Furthermore, this alternator is said to be easy to assemble

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and can be dismantled, and S3 ine assembly, inspection or repair should be simple and easy. The alternator according to the invention is intended to also consist of the smallest possible number of individual parts.

The subject of the invention, with which this object is achieved, is a direct connection with an internal combustion engine Coupled alternator comprising an armature unit and a money unit which are concentric are arranged to the crankshaft of the machine in such a way that a magnetic flux supplied to the armature unit by a rotor unit mounted on the crankshaft and arranged to rotate between the units is varied, characterized in that a cup-shaped rotor unit with claw pole pieces at one end a projection of the engine crankshaft is mounted, which is behind the engine and out of the engine block so protrudes that there is an opening on the The opposite side of the machine shows that the armature unit is adjacent to the circumference of the claw pole pieces of the Rotor unit is arranged that the field unit is arranged in the inner hollow part of the rotor unit and that the anchor unit and the field unit from one non-magnetic support member are held, which extends from the Masehinenblock to cover the units.

The invention is explained in more detail with reference to the exemplary embodiments from illustrated in the drawing; show in it:

Fig. 1 is a general view of a machine unit, on which an alternating current generator according to the invention is coupled directly to a machine is mounted;

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Pig. 2 shows a longitudinal side section of an alternator coupled directly to an engine according to the invention;

Pig. 3 shows a longitudinal side section of another embodiment of the directly with an alternator coupled to an engine;

"4 shows a longitudinal side section of yet another Exemplary embodiment of the alternating current device coupled directly to a machine

nerators; |

Pig. Fig. 5 is a perspective view of one of the Alternator used according to the invention rotor;

and

Pig ^ ö an output power diagram of the alternator according to the invention.

In Pig. 1, reference numeral 1 denotes a direct with a machine coupled alternator, the subject of the invention, the clutch facing away from the Side of a machine block 2 of a conventional machine unit is mounted, which apart from the machine block 2 a | Clutch 3 »a transmission 4 and a gear change lever 6 for adjusting the number of revolutions of a drive shaft 5 and the alternator is driven by the rotation of the engine. This generator 1 is constructed like in Pig. 2 is shown. In Pig. 2, the reference numeral 7 designates a cup-shaped rotor with separate Claw pole pieces 8 and 81, which are connected by means of a non-magnetic ring 9, and its outer

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The appearance is shown separately in FIG. 5. This rotor 7 carries seine.nabe 10 mounted on a projecting part 13 of the crankshaft 12, which is mounted in the machine block 2 by means of roller bearings 11, and is secured by a locking screw 14

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rigidly attached. Reference number 15 denotes a generator cover made of non-magnetic material, such as z. B. aluminum, which is rigidly attached to the side of the machine block by means of a plurality of screws 16 is and comprises an armature core 19 with an armature coil 18, which on its inner circumference by means

ffc of a stepped surface 17 mounted and through Fastening bolts 20 are attached. The reference number 21 denotes a cylindrical field core with a field coil 22, which is wound concentrically thereon and in the hollow part of the cup-shaped rotor 7 below Leaving an air gap free, and this one The field core is on the inner wall of the generator ceiling 15 attached by means of fastening screws 25 so that it is arranged concentrically with the crankshaft 12 together with the armature core 19. The reference number 24 denotes a feeder & rahty of the through the between the attachment side 25 of the field core 21 and the generator cover 15 provided distance and by a

φ guide slot 26 is carried out in armature core 19, where both lead wire 24 and lead wire 27 from the generator to the external terminal are brought out. Here the outlet hole is usually with a rubber bushing 28 for insulation purposes Mistake.

In an arrangement as described above, it is clear that during the operation of the machine and during the rotation

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of the crankshaft 12 and rotation of the rotor 7, the claw pole pieces 8 and 81 generate a rotating PeId and an alternating current is induced in the armature coil 18 and that the generator output drops in proportion to the internal temperature rise. According to the structure According to the present invention, however, the field core with the field coil 22 is directly in the generator cover 15 fitted on the back of the machine and exposed to the atmosphere, so that the increased heat on the machine side does not get there and the heat generated there is dissipated to the aluminum generator cover 15, which is a good heat radiator is, whereby an excellent cooling effect with a considerable improvement of the generator behavior is achieved. There is also the fact that the field core 21 used here has an L-shaped cross section and can be screwed tight from outside the generator cover 15 by means of the fastening screws 23, none Necessity of a mounting base only for the field core 21 to be provided, so that there is a corresponding reduction in dimensions, and in addition, because the armature coil 18 and the field coil 22 together with the generator cover 15 by loosening the screws removed if maintenance, inspection, or repair of these coils is required, a substantial amount Enables improvement in operating efficiency.

Fig. 3 shows another embodiment of the invention. A hub 10 of a rotor 7 extends axially protruding through an opening 50 of a generator cover 15, and a blade fan 29 is at the end * 'the protruding hub 10 if a locking screw

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is tightened , mounted by means of a screw 30, which holds the fan 29 in place to prevent the fan from being stripped off, whereby the generator cover 15 is inevitably cooled as a result of an effective fan run by rotation of the rotor 7 in order to achieve improved heat dissipation of the generator. In Pig. 3, the reference numeral 31 denotes radially directed cooling fins, and the cooling effect can be further improved by these cooling fins. In addition, if necessary, ventilation holes can be provided in the generator cover 15 at desired locations in order to improve the cooling efficiency.

Another embodiment of the invention is based on the Pig. 4 explained. Here, reference numeral 32 denotes an auxiliary cover which, by expanding the circumference of the generator cover · 15 to the outside of a Partition 33 is formed. The reference numeral 34 denotes a camshaft which passes through an opening 35 of the Partition 33 is passed and through the. Locking screw 14 is fixed on the rotor hub 10, and a breaker 36 is operatively connected to this camshaft. The breaker 36 is adjustable mounted on a base 38 connected to the bulkhead by screws 37 so that a breaker cam follower 39 touches the circumference of the camshaft 34. The reference numeral 40 denotes a lubricating felt, which is of a support arm protruding from the base 38 41 is carried to continuously supply a lubricant to the cam surface and prevent the breaker cam follower 39 from being worn. The reference number denotes a dust cover that is used to cover the open

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End of the auxiliary cover 32 attached and attached to the end portion of the Auxiliary cover 32 is fastened by screws 43 to protect the breaker 36. In this embodiment, the breaker 36 on the same Shaft is mounted, the heat generated by the interrupter is negligibly small, so that an improved generator behavior is achieved, as the heat can effectively flow through the generator cover 15 can be discharged, which is provided with the auxiliary cover 32.

According to the embodiments of the invention, the temperature rise of the armature unit and the monetary unit of between 60 and 80 ⁰ C can be held. -If the (temperature increase is limited within this range, the usual isolation class F is sufficient as electrical insulation for the different coils. In conventional direct-coupled AC generators, however, in particular the temperature of the monetary unit rose frequently 100 to 15O ⁰ O, and at 150 ⁰ C For example, insulation class F reaches the permissible limit and thus cannot withstand long operating times. In addition, since the rise in temperature of the field coil leads to an increased electrical resistance of the field coil and an impairment of the field current, there was a tendency to reduce the magnetic flux generated and 6 shows the relationship between the value K "of the revolutions per minute and the output current I of an alternating current generator with field coil temperatures T of 80, 100 and 150 ^° C. According to this figure, U = 2000 U / Min and T «■ 80 ⁰ C the output current I = 13 Am p., while I was ^{11.5 amps at T = 100 0} C and 8 amps at T = 150 ^{0 C.} The starting ·

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Current I of 17 Amp. at N = 6000 rpm and T = 80 ⁰ C fell for T = 10O ⁰ C to 15.5 Amp. and for I = 150 ⁰ C
It follows that the rise in temperature of the field coil has a significant influence on the magnitude of the output current and the superiority of the alternator according to the invention is evident.

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Claims (4)

Claims AC generator coupled to an internal combustion engine, comprising an armature unit and a Field unit includes concentric to the crankshaft the machine are arranged in such a way that a magnetic flux supplied to the armature unit flows through a rotor unit is varied, which is mounted on the crankshaft and for Rotating between the units is set up, characterized in that one Cup-shaped rotor unit (7) with claw pole pieces (8.81) at one end of a Yorsprunges (13) of the machine crankshaft (12) is mounted, which lies behind the machine and protrudes from the machine bloom (2) in such a way that that calibration results in an opening on the side opposite the machine, that the anchor unit (19,1ö) - next to the circumference of the claw pole pieces of the rotor unit is arranged that the field unit (21, 22) inside hollow part of the rotor unit is arranged and that the Aukeinheit and the field unit from a non-magnetic cbet: Carrier component (15) are held, which extends from the MascLinenblock extends out to cover the units. 2. AC generator according to claim 1, characterized in that the armature unit (19, 1t) and the PeIdeinheit (21, 22) firmly attached to the inside of the support component parts (15-) made of non-magnetic material are and the support component is firmly mounted on the machine block (2), whereby the anchor unit and the money unit on the radially outer and radially inner sides of the Rotor unit (7) are arranged. 0098 21/1485 BAD ORiGINAU 3. AC generator according to claim 1, characterized in that that the anchor unit (19, 18) and the field unit (21, 22) firmly on the inside of a protective cover (15) are held, which consists of non-magnetic material, and that the protective cover is firmly attached to Machine block (2) is mounted, whereby the anchor unit and the money unit on the iiadial outer and the radial inner side of the rotor unit (7) are attached. 4. Coupled directly with an internal combustion engine An alternator comprising an armature unit and a money unit concentric with the crankshaft the machine are arranged in such a way that a magnetic flux supplied to the armature unit passes through an eotor unit which is mounted on the crankshaft and arranged to rotate between the units, characterized in that a cup-shaped claw rotor is provided in which a first magnetic path is formed which extends radially from a Extends the end of a gate of the engine crankshaft, which is located behind the machine and after outside the machine block protrudes that a plurality of first claw pole pieces of the same polarity is formed extending axially from the end portion of the first magnetic path and spaced from each other are arranged to form a plurality of second claw pole pieces of the other polarity which are dereFfc are mechanically coupled that they are arranged between the first claw pole pieces and a second magnetic path form, at its other end there is an annular part, and that the pole pieces of the both polarities are mechanically connected to one another by non-magnetic material on the inside, 00 9 8-21 / 148S that also an armature core with an armature coil with a small air gap between the anchor core and the outer circumference the claw pole pieces is arranged that a field coil is grounded on a cylindrical Peldkern is wound with an It-shaped cross-section, that the field core is arranged on the inside of the Elauen rotor in such a way that one side of the L-cross section of the core of the hub of the rotor in connection with the first Elauen pole pieces, while the other side of the! cross-section is opposite to the ring-shaped Part of the second Elauen pole pieces with a small one Opposite intermediate air gap, and that the armature core and the Peldkern are firmly held on the inside of a non-magnetic Irägerbauteils, which extends from the machine block to cover the cores. 009821/148 * Blank page