JPH0357721A - Electric-motor vehicle - Google Patents

Abstract

PURPOSE:To prevent the adoption of a large-sized main bearing by fitting a rotary shaft on a rotor side into a hollow shaft having a fixed stator, and providing the main bearing between the above shafts at a position nearly coincident with the tire center, and an auxiliary bearing between an internal face of a cover bracket on the other side of the rotor and a spindle shaft. CONSTITUTION:A stator 2 of a direct drive motor 1 is fixed on an outer periphery of a hollow spindle shaft 3, and a rotor 4 is arranged on an outer periphery of the stator 2. A rotary shaft 5 is provided at the central part of a rotor bracket 13 supporting the rotor 4 and joined to a wheel disc 12 and moreover inserted into a hollow spindle shaft 3. A main bearing 6 supports the rotary shaft 5 rotatably to the spindle shaft 3 at a position nearly coincident with the center line of a tire 9. An auxiliary bearing 8 is provided between another cover bracket 7 supporting the rotor 4 and the spindle shaft 3. Thus the main bearing 6 is not required to support the tire 9 one-sidedly, and the adoption of a large-sized main bearing can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to an electric vehicle, particularly an electric four-wheel vehicle, which uses direct drive wheels as driving wheels. Conventional technology Conventionally, a direct drive wheel, which incorporates the stator and rotor of a direct drive motor, which is a driving power source, between the wheel shaft and the disk has been used, for example, in the actual opening/closing 6
It is listed in Publication No. 2-139814 and belongs to the public domain. Research and development of two-wheel, three-wheel, and four-wheel electric vehicles using these direct drive wheels as drive wheels is progressing, and some have been successfully implemented. The direct drive wheel described in the above-mentioned Jitsubishi No. 62-139814, as illustrated in FIG.
The spindle shaft d, which houses the stator b of the direct drive motor a, is integrally formed with the upright C, which is the connection point for the suspension arm e. On the other hand,
The rotor f using permanent magnets is connected to the brackets g and g placed on the ←]4 side, and the two brackets on both sides g. The rotating portion including the rotor f is supported by the two left and right supports h, h installed between the inner diameter of the spindle g and the outer diameter of the spindle shaft d. That is, the rotation {I! Support (hold) one part
The bearings h and h are the suspension arm e 41
It also serves as a bearing for the direct drive wheel (traveling device), which is attached to the i-body and independently suspended.

Problems to be Solved by the Invention As in the conventional example shown in FIG. 2, the bearing h that holds the rotating side portion of the direct drive motor a also serves as the bearing of the direct drive wheel (traveling device) itself. This can be said to be rational in that it can reduce the number of support points, which contributes to simplifying the structure and reducing internal resistance. However, there is a considerable distance between the center n of the tire, which is the final point of application of the vehicle weight, and the position of the fulcrum provided by the bearing h. Therefore, in order to improve the performance of electric vehicles, it is necessary to
When using a long direct drive motor a for t+, or when using a motor with a small gap between stator b and rotor f, the stability and reliability of the holding state of rotor f during running may become a problem. Become.

As a solution to this problem, if you only select the size or the size of the armrest of a direct drab wheel (with a horizontal pedestal), for example, in a cantilever supported horizontally using an ancular bearing, the armrest dimensions will be Very thick. Furthermore, in the case of double-sided support using radial bearings, there is a big problem of increasing the weight and manufacturing cost in order to ensure the dimension 1+'i degree and axial rigidity required for the rotor f. , these are the major issues to be solved. on the other hand,
The conditions necessary to maintain the rotating parts of a direct drive motor (traveling device) of a vehicle and the condition 1 necessary to maintain the rotating parts of a direct drive motor are not necessarily in a consistent range. In the 12th year of advancing the performance improvement of electric tunnels, various problems of consistency have arisen. Therefore, the first objective of the IJJ is to support the rotor of a direct drive motor by using a main bearing with a fulcrum at a position that is almost coincident with or close to the center of the tire, and a part of the bearing function. It is an object of the present invention to provide an electric vehicle whose driving wheels are direct drive wheels that are improved in a structure that uses an auxiliary bearing with a different small cross section.

Means for Solving the Problems As a means for solving the problems of the above-mentioned prior art, the electric vehicle according to this iJ has a direct drive wheel as a driving wheel, as shown in an embodiment in FIG. 1 of the drawings. In an electric vehicle, a spindle shaft 3 having a hollow structure to which a stator 2 of a direct drive motor 1 is attached, and a rotation 4 of a rotor 4 which is fitted in a concentric arrangement into a hollow portion 3a of the spindle 3.
! III 5, and an auxiliary bearing 8 is installed between the inner diameter surface of the other Kanoheh bracket 7 on the same rotor 4 side and the outer diameter surface of the spindle shaft 3. .

The moment that will be generated due to the weight of the vehicle loaded on the working tire 9 and the reaction force that the tire 9 receives from the road surface is:
The main bearing 6, whose support point 02 almost coincides with the center OI of the tire 9, which is the final force application point of the vehicle's weight, carries the load almost as a simple load. Since part of the load is also borne by the other auxiliary bearing 8, the rotating part (rotor 4) of the direct drive motor 1 is held stably. Embodiment Next, the embodiment of the present invention shown in FIG. 1 will be explained.

The wheel 10 is composed of a rim 11 to which a tire 9 is attached and a wheel disc l2. wheel disc 1
A rotor bracket 13, which is the rotating side portion of the direct drive motor 2, is fixed to the inside of the rotor 2 with several poles 14 and nuts 15. A stator 2, which is a fixed side portion of the direct drive motor 1, is attached to the outer periphery of a spindle shaft 3 having a hollow structure. A rotor (field magnet) 4 made of permanent magnets is arranged around the outer periphery of the stator 2 . The rotor 4 is connected and supported by rotor brackets 13 disposed on both sides thereof and a cover bracket 7 on the opposite side by bolts l6. Inside the center of the rotor bracket l3 that supports the rotor 4, a rotary plate l7 having a short rotary shaft 5 facing inward (rightward in the figure) is integrally coupled with several bolts l8. Actually, this rotating plate 22 is connected to the wheel disc l2 at the pole 14. The rotating shaft 5 is fitted into the hollow portion 3a of the spindle shaft 3 from the distal end side of the hollow-structured spindle shaft 3 in a pivoting arrangement, and P? The rotating shaft 5 is rotatably supported by a main bearing 6 installed between the two. The main rotating shaft 6 has a stop ring 19 fixed on the inner diameter side of the spindle shaft 3, and a presser cap 2 tightened with a pole 20 passed through the center of the rotating shaft 5.
The position is fixed by 1. Thus, the main bearing 6 has its support point (center of support 02) at the weight of the vehicle! ! It is installed at a position that almost coincides with the center 01 of the tire 9, which is the final force application point of the tire 9.

Further, a sleeve support 1 oil pan 8 is installed between the inner diameter surface of the cover bracket 7 on the right side of the first section and the outer diameter surface of the spindle holder 3, and the cover bracket 7 is held in a rotatable position. This auxiliary bearing 8
= has been done. At the right end of the spindle shaft 3 in the figure, although not shown, for example, there is an amplifier light (knuckle joint) that is the connection point for the suspension arm of a single-woman suspension, and this direct drive wheel is supported on the vehicle body. It is (suspended). The effects of the present invention are as described in detail in conjunction with the examples, and this effect {! The direct drive wheels, which are the drive wheels of the electric i1i vehicle according to No. 1, have a structure in which the center O1 of the tire 9, which is the point of application of the vehicle weight, and the support point O2 of the main bearing 6 are so close to each other that they almost coincide with each other. The main bearing 6 supports the load of the vehicle weight extremely rationally and efficiently, like a simple load, and generates a small moment. Even when the drive motor 1 is employed, the load burden on the main bearing 6 and, by extension, the load burden on the auxiliary bearing 8 does not increase much. Therefore, not only is it not necessary to increase the size of the main bearing 6, but the problem of deformation of the motor structure is small, so there is no problem in adopting a motor with a small gap between the stator 2 and rotor 4, and therefore, it is possible to This greatly expands the degree of freedom in improving the performance of vehicles.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a direct drive wheel according to the present invention, and FIG. 2 is a cross-sectional view of a conventional direct drive wheel. l...Tirek 2...Stator 3a...Spin 5...Rotating shaft 6...Main bearing 8...Auxiliary bearing Drive motor 3...Spindle shaft Hollow part of dollar shaft 4...・Rotor 7...Cover bracket Figure 2 (1--)

Claims (1)

[Scope of Claims] [1] In an electric vehicle having a direct drive wheel as a driving wheel, a spindle shaft having a hollow structure to which a stator of a direct drive motor is attached, and a spindle shaft that is fitted concentrically into the hollow part of the spindle shaft. A main bearing is installed between the rotating shaft on the rotor side, and an auxiliary bearing is installed between the inner diameter surface of the other cover bracket on the same rotor side and the outer diameter surface of the spindle shaft. An electric vehicle.