Abstract: A control circuit for a blender provides low-cost power conditioning through the use of a high resistance which provides temporary power for operation of low-voltage logic circuitry and low-voltage switches for a time sufficient to switch the motor on, and a lower resistance which provides sufficient power for maintaining the motor on state indefinitely as instructed by the low-voltage logic circuitry. Low average power dissipation is provided by powering the low-voltage logic circuitry and low-voltage switches using the high resistance in a standby mode and switching in the lower resistance only when the motor is activated.

Abstract: A method is provided for controlling a position of an electric dc brush motor (22, 24) including the steps of supplying drive current (104) to drive the electric motor and calculating (70, 108) a coast constant for the motor. Current through the motor is monitored (80) and motor speed (66) is determined in response to monitored motor current. Electrical current to the motor is interrupted (50) in response to the calculated coast constant (70, 106) and motor speed when it is desired to stop the electric motor so that a brush of the motor will come to rest at a location on a commutator segment of the motor (22, 24).

Abstract: A motor system includes four brushes electrically connected to a rotor. A stator includes two magnetic poles. A circuit selectively rotates the rotor at a first speed by applying a first voltage to a first of the brushes and a second voltage to a second of the brushes. The circuit selectively rotates the rotor at a second speed by applying the first voltage to the first brush or the second brush, and applying the second voltage to a third of the brushes and/or a fourth of the brushes.

Abstract: A bidirectional DC motor comprising a commutator (6) which can be connected to a constant voltage source by a first and a second brush. The second brush is disposed opposite one side of the first brush in a spaced disposition with respect to the periphery of the commutator, which spacing correlates with a desired motor characteristic to provide a relatively convenient arrangement for switching the direction of rotation of a DC motor. In addition to the second brush (8) provided for one direction of rotation, the commutator (6) also has a third brush (9) for the counter-direction of rotation and is disposed in a spaced disposition with respect to the periphery of the commutator (6), which spacing correlates with the desired motor characteristic for the counter-direction of rotation. The first brush (7) is connected to one pole (+) of the constant voltage source (10) and the two other brushes (8, 9) are connected to the other pole (-) of the constant voltage source (10) by a switch (S1, S2) respectively.

Abstract: Disclosed is an improvement to the stability of D.C. motor brushes mounted in brush boxes with wings is improved by angling the wings toward the commutator such that the brush spring contacts the brush at one or more points intermediate the ends of the brush. Improved cooling is provided by utilizing an end plate with apertures and a brush plate which in combination with the commutator, provides a brush plate aperture for cooling air flow. In a preferred embodiment, speed variations of the motor can be achieved by selectively disconnecting one or more brushes in a four brush embodiment reducing the torque and rotating speed of the motor. In a preferred embodiment, the use of a diode to interconnect same polarity brushes permits a speed change to be accomplished by selectively connecting one or the other end of the diode.

Abstract: The invention provides a method of commutation control, for changing the speed of a direct current electric motor of the constant flux type, having an encapsulated inductive winding with n poles, each of which is supplied by a separate brush. In this method, a speed at a level i, where i is in the range 1 to n-1 inclusive, is obtained by connecting a group of i+1 brushes to the terminal of the direct current supply source. The state of connection of the brushes is modified in accordance with a control characteristic which comprises modifying the composition of the group of i+1 brushes to be connected in order to obtain a motor speed at a predetermined level i, and/or by interrupting the connection of one of two consecutive brushes to the brush previously connected during a speed changing operation.

Abstract: It is proposed to obtain a switching device for the electrical switching (i.e. switching on and off or reversing the direction of rotation) of electric tools, especially electric hand tools such as drills, grinders and the like, by mounting a rotatable setting ring on the outer cylindrical housing of the electric tool and positioning it opposite the end shield at the B-end of the electric motor inside the housing in such a manner that inwardly pointing projections of the setting ring will grip a plate or switching ring on the electric motor and will cause the said plate or switching ring to perform a slave motion for switching the electric motor on and off or reversing its direction of rotation whenever the external setting ring is subjected to a manual rotation.

Abstract: This invention relates to a speed changing device, giving at least two motor speeds, for an electric motor supplied with direct current. It is applicable to motorized ventilating fan units designed for the air cooling of heat engines, mainly for automobiles.The speed changing device is characterized in that it includes a contactor having at least two positions whereby, in the first position of the contactor, not more than three of the brushes are supplied with electrical current so as to obtain a first motor speed (low speed), while in the second position of the contactor, all of the brushes are supplied with electrical current so as to obtain the greater motor speed (high speed).

Abstract: A two-speed permanent magnet D.C. electric motor has a housing, permanent magnets carried by the housing, and an armature assembly installed in the housing. The armature assembly has a shaft rotatably mounted in the housing, first coil windings, a first commutator connected to the first coil windings, second coil windings and second commutator connected to the second coil windings. A first set of brushes is carried by the housing and engages the first commutator for applying a D.C. voltage to the first coil windings to cause rotation of the armature assembly at a first speed. A second set of brushes is carried by the housing and engages the second commutator for applying the same D.C. voltage to at least the second coil windings to cause rotation of the armature assembly at a second speed.

Abstract: A wiper apparatus using a three brush, permanent magnet motor in which a zener diode has a cathode connected to the low speed brush and an anode connected to the high speed brush. The zener breakdown voltage of the zener diode is chosen so that it reverse conducts during at least some portion of each wipe cycle during operation with the high speed brush on a wet window to limit peak wiper speeds and reduce strain on the wiper mechanism. Variations including a transistor, relay or additional zener diode controlled by the zener diode and connected in parallel therewith provide for reduced current and therefore power dissipation in the zener diode at the expense of somewhat limited speed limiting.

Abstract: The wear upon at least one of several carbon brushes in a brush holder is monitored by a lever one arm of which is biased against the rear end face of a selected brush by a spring and another arm of which actuates a microswitch in response to a predetermined amount of wear upon the brush as a result of engagement with a commutator or a slip ring, namely in response to a predetermined angular displacement of the lever from a starting position which is assumed by the lever when its first arm engages a freshly inserted brush.

Abstract: In a fuel pump driving apparatus for a vehicle engine including a fuel injection system, the selection of a plurality of energizing circuits each formed by the combination of two or all of three brushes of a fuel pump drive motor is effected in accordance with the load conditions of the engine, thereby changing the rotational speed of the motor and hence the fuel quantity delivered from the fuel pump. When the occurrence of a fault in one of the energizing circuits is detected, the driver is informed of the occurrence of the fault and in addition a faulty-condition controller controls switching means in such a manner that the drive motor is energized through another one of the energizing circuits.