An electric power-steering device has a speed-reducing mechanism (17) for reducing the speed of an output shaft (16) of an electric motor (15). The speed-reducing mechanism (17) has an internal gear (39) engaged and rotated with the output shaft (16) and an external gear (40) with which the internal gear (39) internally meshes. A drive pulley (41) rotatable together with the external gear (40) and a driven pulley (42) provided so as to surround a steering shaft are connected by an endless belt (43). Speed reduction is obtained by the internal gear (39) and the external gear (40), and the speed-reducing mechanism (17) as a whole achieves a high reduction ratio without greatly reducing the diameter of the drive pulley (41).

Electric power-steering device

A motor case (31) in which a stationary portion (35) is fixed, and a gear case (41) in which a gear mechanism (SD) is accommodated are made of aluminium, most heat generated from the stationary portion (35) at the time of actuation of a brushless wiper motor (20) can be directly dissipated outside from the motor case (31). That is, compared with conventional technique, heat transmitted to the motor case (31) can be efficiently dissipated outside, and the motor case (31) does not reach high temperature. Therefore, as a matter of course, reduction in size and weight can be achieved, suppression of electromagnetic noise can be achieved, and heat-resistance strength can be enhanced. Expensive components capable of resisting high temperatures are not required, and reduction in manufacturing cost can be achieved.

Brushless wiper motor

To provide an alignment changing control device (37) that includes: a motor drive section (25) which adjusts electrical power supplied to a motor of the electric actuator according to an operation command and, when receiving an operation inhibiting signal, limits or stops supplying the electrical power to the motor; a motor temperature estimating section (28) for calculating an estimated temperature of the motor from at least a current supplied to the motor, an outside air temperature and a vehicle speed, based on heat balance relationship; and a comparator (26) which transmits the operation inhibiting signal to the motor drive section when the estimated temperature of the motor calculated by the motor temperature estimating section is higher than a predetermined temperature, which is equal to or lower than an operation allowable temperature of the motor.

Alignment changing control device

A drive device for a vehicle, having excellent workability of assembly. A drive device (10) for a vehicle, having a first electric motor (M1), a power distribution mechanism (first gear device)(16), a second electric motor (M2), and a stepped automatic speed changer (second gear device)(20), wherein the first electric motor (M1) and the power distribution mechanism (16) are constructed as a first unit (70), the second electric motor (M2) and the automatic speed changer (20) are constructed as a second unit (100), and an output shaft (96) of the power distribution mechanism (16) and an input shaft (104) of the automatic speed changer (20) are coupled, thereby power transmission between the first unit (70) and the second unit (100) being enabled. In the construction above, the first unit (70) and the second unit (100) are individually assembled first and then the drive device (10) is assembled by coupling the output shaft (96) of the power distribution mechanism (16) and the input shaft (104) of the automatic speed changer (20), and as a result, workability in assembly is improved.

Drive device for vehicle

An electric power steering system ( 1 ) includes a tubular sensor housing ( 34 ) which accommodates a torque sensor ( 20 ), a gear housing ( 32 ) which accommodates a speed reduction mechanism ( 24 ), and an upper bearing ( 40 ) and a lower bearing ( 41 ) which rotatably support a steering shaft ( 3 ) on opposite sides of the speed reduction mechanism ( 24 ). The gear housing ( 32 ) includes a tubular lower housing ( 37 ) supporting the lower bearing ( 41 ), and an upper housing ( 36 ). The upper housing ( 36 ) includes an inner tube ( 67 ), an outer tube ( 68 ), and an annular connection wall ( 69 ) connecting the inner tube ( 67 ) and the outer tube ( 68 ). The outer tube ( 68 ) is press-fitted in the lower housing ( 37 ). The inner tube ( 67 ) is press-fitted to an inner periphery ( 72 ) of a lower portion ( 71 ) of the sensor housing ( 34 ), whereby the inner tube ( 67 ) has a reduced diameter. As a result, an outer ring ( 44 ) of the upper bearing ( 40 ) is tightly fitted and supported in the inner tube ( 67 ).

Electric power steering system

PROBLEM TO BE SOLVED: To reduce labor required for assembling work and to protect a motor against damage during the assembling work in an electric power steering system where the output shaft of the motor and the driving gear of a reduction gear are provided integrally. SOLUTION: The reduction gear housing 15 of a sub-assembly 62 is coupled integrally with a motor housing 25 and holding an output shaft 21. The outer circumference of a rotor 22 held on the output shaft 21 is surrounded by the motor housing 25 and protected. The stator yoke 42 of a stator unit 23 is fitted to the cylindrical surface on the inner circumference 24 of the motor housing 25. The stator yoke 42 is guided movably in the axial direction but unmovably in the radial direction with respect to the rotor 22, thus preventing contact with the rotor 22. COPYRIGHT: (C)2005,JPO&NCIPI

Electric power steering system nd its manufacturing method

A second housing is aligned with a first housing at a predetermined position using positioning means that determines the mounting position of the housing with respect to the first housing at the predetermined position; steering shaft supporting sections and output shaft supporting sections are provided in the first housing and the second housing respectively while the housings being mounted using screws or the like; the second housing is removed temporarily from the first housing; a steering shaft and an output shaft are supported using the steering shaft supporting sections and the output shaft supporting sections; and the second housing is aligned again with the first housing at the predetermined position using the positioning means and mounted.

Method for producing electric power steering apparatus

An electric power steering assembly includes an electric motor, a reduction mechanism for reducing the speed of an output rotation of the electric motor, and a reduction-mechanism housing accommodating therein the reduction mechanism. The electric motor includes: an output shaft rotatably supported by the reduction-mechanism housing, a motor housing formed integrally with the reduction-mechanism housing, a rotor, and a stator assembly accommodated in an annular space defined between the rotor and the motor housing. When the stator assembly is assembled in the annular space via an opening at an end portion of the motor housing, a guided portion on an outside circumference of a stator yoke is guided by a guide portion on an inside circumference of the motor housing.

Electric power steering assembly and method for fabricating same

The invention provides a motor-driven power steering apparatus which can achieve a predetermined speed reduction ratio even in the case that the motor-driven power steering apparatus is constituted by a pair of spur gears or helical gears, and can secure a sufficient gear strength on the basis of a simple structure. In a motor-driven power steering apparatus in which a rotating torque of an electric motor ( 7 ) is transmitted to a steering shaft by a drive gear ( 6 ) provided in an output shaft of the electric motor ( 7 ) and a driven gear ( 5 ) provided in the steering shaft, and a speed reduction ratio is equal to or more than 3, the steering shaft and the output shaft of the electric motor ( 7 ) are arranged in almost parallel, a center distance between both the shafts is equal to or more than 35 mm and equal to or less than 90 mm, and the drive gear ( 6 ) is configured such that a number of teeth is equal to or more than 6 and equal to or less than 15, a module is equal to or more than 0.8 and equal to or less than 1.5, a tooth depth is equal to or less than 2.4 times of the module, and a pressure angle is equal to or more than 14.5 degrees and equal to or less than 30 degrees, and a torsion angle is equal to or more than 0 degrees and equal to or less than 40 degrees.

Yoshikazu Kuroumaru

Papers

Electric power steering system nd its manufacturing method

Method for producing electric power steering apparatus

Electric power steering assembly and method for fabricating same

Motor-driven power steering apparatus

Electric power steering assembly