1. Field of the Invention
This invention relates to inductor type dynamoelectric motors and, more specifically, to a support and positioning structure for conductors of a stator assembly of such a motor.
2. Background Art
Dynamoelectric machines are commonly used as motors for converting electrical to mechanical energy. Inductor type dynamoelectric motors may be used as adjustable speed drives for high speed operation. A dynamoelectric machine may also be used for electrical generation by driving its rotor in reverse thereby producing energy in the armature windings. Inductor type dynamoelectric machines are generally characterized by a stator which includes both AC armature and DC exitation coils surrounding a coil-less rotor. In this configuration, there are no rotating field or armature coils, slip rings, brushes and associated connections which are common to machines having rotating windings. Since inductor type dynamoelectric machines contain fewer rotating parts, have a more rugged rotor construction and are particularly suitable for high speed application. One version of such an inductor type dynamoelectric machine, employs a circumferentially distributed arrangement of C-shaped armature elements surrounding a generally cylindrical field coil which in turn encloses a transverse pole magnetic rotor. U.S. Pat. Nos. 437,501 and 2,519,697 and 3,912,958 describe earlier machines of this type of design.
More recent versions of such inductor type machines are disclosed in commonly owned U.S. Pat. Nos. 4,786,834 and 4,864,176. In these patents, a spool-like support structure supporting field windings and armature elements is disclosed. The spool-like structure is made of a nonmagnetic material and has a hollow, elongated central portion extending concentrically about a longitudinal axis. This central portion supports a field coil and defines an interior longitudinal passageway for accommodating the insertion of a coaxial rotor. End portions are located at each end of the central portion and extend radially outward therefrom. Each of the end portions is preferably provided with radially oriented grooves in its axially outermost surface. The grooves are configured to receive and orient legs of generally C-shaped armature coil elements arranged in a circumferentially distributed pattern about the periphery of the spool-like structure. The armature elements are thereby positioned in three orthogonal directions.
Other features, advantages and benefits of these dynamoelectric machines, including the stator support structures thereof, are described in detail in U.S. Pat. Nos. 4,786,834 and in 4,864,176. Each of these patents is incorporated herein by reference and made a part of this disclosure.
The C-shaped armature elements contain armature windings thereon which carry an AC current and generate a magnetic flux which drives the rotor when the machine is used as a motor. In this situation, the current must be supplied to each of the circumferentially oriented C-shaped armature element's windings. Typically, low power, dynamoelectric machines require less current through the armature windings thereby requiring lighter gauge windings. Accordingly, the conductors transmitting current to the windings may also be of a relatively light gauge. Because lighter gauge conductors are used in these low power, dynamoelectric machines, there have been few problems connecting the armature windings to the conductors, supporting the conductors, and connecting the conductors from the windings to a power supply wire outside of the dynamoelectric machine. For example, a light gauge power supply wire is typically fed through the housing of a low power dynamoelectric machine. The wire is then connected to a printed circuit board which contains a network of conductors therein which distributes the current therethrough and into the armature windings which are typically soldered to portions of the network. In this situation, the conductors are of relatively light gauge and are supported within the circuit board.
In high power high speed rotation dynamoelectric machines, the power to supplied to the armature windings is greater than in low power machines. These machines require high frequency currents. However, at high frequency, the effective AC resistance of conductors increases with increasing frequency. To reduce the increase of conductor resistance at high frequency, the armature conductors may be multiple isolated ribbon-like strands. Therefore, heavier gauge conductors are needed to supply the necessary current. However, these higher gauge conductors are often too heavy and bulky to be supported by a printed circuit board or similar type support structure. Also, the conductors are not easily connected to the armature windings.
It is therefore desirable to provide a system for supporting conductors which supply current to the armature windings of a high power, high speed dynamoelectric machine. It is also desireable to provide a system for connecting the conductors to the armature windings and to provide a system which does not significantly increase the size of a dynamoelectric machine.