JPH07274436A - Driving arrangement for motor car - Google Patents

Abstract

PURPOSE:To miniaturize the whole of a driving arrangement for motor cars and improve the pinion accuracy of the shaft of its motor, by spline-joining one end part of a pinion to the output shaft of the motor, and concurrently, by bolt-fixing the pinion on the output shaft with a predetermined bolt via a through hole bored in the center axis part of the pinion. CONSTITUTION:A pinion 11 is spline-joined-in its one end part to an output shaft 1A of a driving motor 1, and a blind hole 1a is bored in the central part of the end part of the output shaft 1A along its axial line, and further, from the opening part side thereof, a spigot part 1b and a screw hole part 1c are formed in succession. Also, on the outer periphery of the output shaft 1A, an axial spline 1s is formed, and in the center axis part of the pinion 11, a through hole for spigot-joining it to the output shaft 1A is bored, and then, by a pinion bolt 15, the pinion 11 is bolt-fixed on the output shaft 1A of the driving motor 1 while it is spigot-joined to the output shaft 1A. As a result, the output shaft IA of the driving motor 1 and the center axis of the pinion 11 are so set as to coincide with each other, and both can be one with each other firmly, and thereby, the pinion accuracy of the shaft of the motor 1 can be improved without the deterioration of the miniaturization of the whole of a driving arrangement for motor cars.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive device for an electric vehicle, and more particularly to a drive device for an electric vehicle provided with a drive motor and a reduction gear mechanism for transmitting the rotational force of the drive motor to both wheels.

[0002]

2. Description of the Related Art In electric vehicles, it has been an important issue to improve the performance of an on-vehicle battery and ensure its capacity. In this case, in order to secure the capacity, it is necessary to secure as much occupied area as possible with a limited floor area. Therefore, it is important to reduce the size and weight of each component such as the drive mechanism. Is being watched.

In order to meet the demands of the times mentioned above, the conventional drive system for an electric vehicle adopts a method of engraving a gear at the tip of the output shaft of the drive motor in order to reduce the size of the reduction gear mechanism, for example. This reduces the number of gears to reduce the size of the entire drive system.
It is expected to have secondary effects, such as reducing the effort during assembly and improving productivity.

[0004]

However, in the above-mentioned conventional example, although the labor at the time of assembling is reduced and it is suitable for downsizing as a whole, the step of directly gear cutting the gear on the motor shaft is performed. Since the motor shaft is required, the gear cutting process is troublesome because the motor shaft is relatively long, but the gear precision is likely to vary. Also,
Even in the heat treatment step, there has always been a troublesome matter that, for example, the motor shaft is always taken into consideration so that the shaft itself is not thermally deformed.
Further, even after the gear has been installed in the electric vehicle, the drive motor must be replaced even if a gear abnormality occurs.

[0005]

An object of the present invention is to improve the inconvenience of the conventional example, and in particular to improve the gear precision of the motor shaft without impairing the downsizing of the entire apparatus in the above-mentioned conventional example, and to improve the productivity of the entire apparatus and It is an object of the present invention to provide a drive device for an electric vehicle with improved maintainability.

[0006]

According to the present invention, a drive motor for an electric vehicle and a reduction gear mechanism connected to an output stage of the drive motor and transmitting the output of the drive motor to wheels via a differential gear mechanism. It has and. The reduction gear mechanism includes a small gear provided on the output shaft of the drive motor and a counter gear that meshes with the small gear.
Then, the small gear is spline-coupled to the output shaft of the drive motor at one end thereof, and the small gear is bolted to the output shaft of the drive motor with a predetermined bolt through a through hole provided in the central shaft portion. It adopts the configuration of doing. This aims to achieve the above-mentioned object.

[0007]

[Operation] The small gear 11 is preformed on the drive motor 1 separately from the output shaft 1A, and is spline-coupled to the output shaft 1A. In connection with the pinion bolt 15, the cutout portions 11c, 1 having a width across flats are actually used.
The work can be efficiently advanced by the spanners 20 and 21 using the 1c. Therefore, the pinion bolt 15 is in a stable and solidly integrated state as if it were formed at the tip of the output shaft 1A from the beginning.

On the other hand, when the pinion 11 fails, the pinion bolt 15 is removed and the spline connection is released, so that the pinion bolt 15 can be easily detached from the output shaft 1A.
Here, since the rotational force of the drive motor 1 is transmitted to the drive motor 1 via the spline connection, the pinion bolt 15
The rotational force of the drive motor 1 is not applied to the motor. Therefore, the spigot coupling between the small gear 11 and the output shaft 1A is maintained semi-permanently with high precision and robustness.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. In the embodiment shown in FIGS. 1 to 7, a drive motor 1 for an electric vehicle and an output stage of the drive motor 1 are connected to an output of the drive motor 1 via a differential gear mechanism 3 to the left and right wheels 5. , 7, and a reduction gear mechanism 9 for transmission to the gears 7. Reference numeral 2 indicates a gear case. The drive motor 1 is spigot-coupled to a part of the gear case 2 as shown in FIG. 2, and is fixed by a bolt (not shown).

The reduction gear mechanism 9 is, as shown in FIG.
A small gear 11 mounted on the output shaft 1A of the drive motor 1,
The counter gear 13 meshing with the small gear 11 is included. Further, the counter gear 13 is coaxially equipped with a clutch mechanism 14. Reference numeral 14A indicates a slide gear. Further, reference numeral 14B indicates a dog clutch portion. The slide gear 14A moves in the direction of arrow A in FIG. 3 by operating the clutch lever 14a, so that the drive motor 1 side and the differential gear mechanism 3 side are connected or disconnected.

The small gear 11 is spline-coupled to the output shaft 1A of the drive motor 1 at one end as shown in FIG. Here, the output shaft 1A of the drive motor 1 is shown in FIG.
As shown, a bottomed hole 1a is provided in the center of the tip end portion along the axis, and a spigot portion 1b and a screw hole portion 1c are sequentially formed from the opening side. Also, this output shaft 1A
An axial spline 1s is formed on the outer periphery of the. This enables the aforementioned small gear 11 to be detachably spline-coupled.

Further, as shown in FIG. 4, the small gear 11 is provided with a through hole 11A for the spigot connection with the output shaft 1A described above at the central shaft portion thereof, and a predetermined pinion is provided through this through hole 11A. A bolt 15 is spigot-coupled to the output shaft 1A of the drive motor 1 and bolted. Here, reference numeral 11a indicates a gear portion (actually, a helical gear is formed), and reference numeral 11s indicates a hole spline formed corresponding to the shaft spline 1s of the output shaft 1A described above.

Therefore, the small gear 11 and the output shaft 1A are
The rotation center axes can be surely matched, and the rotational force on the drive motor 1 side can be surely transmitted to the small gear 11.

Further, as shown in FIG. 4 (B), the small gear 11 is formed with cutout portions 11c, 11c having a width across flats.
As a result, a hooking portion 11d for detachment is formed. When the above-mentioned pinion bolt 15 is installed, the work of engaging or disengaging the pinion bolt 15 is facilitated by the spanners 20 and 21 as shown in FIG. FIG. 6 shows a state in which the small gear 11 is disengaged from the shaft spline 1s of the output shaft 1A. Here, reference numeral 1
1h shows a removal jig.

Further, FIG. 7 shows the pinion bolt 15.
The pinion bolt 15 has a small gear 11 at the center thereof.
Is provided with a spigot portion 15a for matching the rotation axes of the output shaft 1A and the output shaft 1A, and a screw portion 15b for fixing the small gear 11 to the output shaft 1A is provided at the tip end portion.

Next, the operation of the above embodiment will be described.

The pinion gear 11 has a drive motor 1 and an output shaft 1A.
Separately, it is formed in advance and is spline-coupled to the output shaft 1A, and then the central axis thereof is fixed to the same and robustly by the spigot coupling by the pinion bolt 15. At the time of the spigot connection by the pinion bolt 15, the work can be efficiently advanced by the spanners 20, 21 and the like by utilizing the cutout portions 11c, 11c having the width across flats. Therefore, the pinion bolt 15 is in a stable and solidly integrated state as if it were formed at the tip of the output shaft 1A from the beginning. On the other hand, when the pinion 11 fails, the pinion bolt 15 is removed and the spline connection is released, so that the pinion bolt 15 can be easily detached from the output shaft 1A. Here, since the rotational force of the drive motor 1 is transmitted to the drive motor 1 via the spline connection, the rotational force of the drive motor 1 is not applied to the pinion bolt 15. Therefore, the spigot coupling between the small gear 11 and the output shaft 1A is maintained semi-permanently with high precision and robustness.

As described above, in this embodiment, the drive motor 1
A shaft spline 1s is provided on the outer diameter of the tip of the output shaft 1A of
Reference hole (bottomed hole) for connecting the spigot in the center of the tip surface 1
Since a is provided and the screw hole portion 1c is provided, the small gear 1
1 can be easily and coaxially mounted with high precision,
This small gear 11 can be machined separately from the output shaft 1A and matched with the output shaft 1A with high accuracy and speed, and when the small gear 11 fails, the small drive gear 1 can be processed without replacement. Only the gear 11 can be replaced, and the maintainability can be improved in this respect.

Further, since one end of the small gear 11 is spline-coupled to the output shaft 1A, the small gear 11 can be further miniaturized. Therefore, the teeth of the gear are carved on the output shaft 1A. It is possible to obtain the small gear 11 in a state close to that of, and for this reason, it is possible to reduce the size to about the same level as in the case of the conventional example described above. As described above, in the present embodiment, it is possible to improve the gear accuracy of the motor shaft and to improve the productivity and maintainability of the entire device without impairing the miniaturization of the entire device in the above-described conventional example. Has become.

[0020]

As described above, according to the present invention, a small gear to be mounted on the output shaft of the drive motor is separately formed in advance, and the small gear is limited to one end thereof and spline-coupled to the output shaft. Since the small gear is bolted to the output shaft of the drive motor with a predetermined bolt through the through hole provided in the central shaft portion, the central shaft of the output shaft of the drive motor and the central shaft of the small gear are set to be the same and both Not only can it be solidly integrated, but also the pinion gear can be made even smaller, so that it is possible to obtain a pinion gear in a state close to that when the gear teeth are carved on the output shaft. Therefore, it is possible to reduce the size to about the same level as in the case of the conventional example described above, and in the case of a small gear failure, it is possible to replace only the small gear without replacing the drive motor. Moreover, since the rotational force of the drive motor is transmitted to the drive motor through the spline coupling, the rotational force of the drive motor is not applied to the pinion bolts. The connection between the gear and the output shaft will be maintained semi-permanently and robustly with high accuracy, and since it will be constructed and function as described above, the gear of the motor shaft will not be impaired without impairing the miniaturization of the entire device in the conventional example described above. It is possible to provide an unprecedented excellent drive device for an electric vehicle, which can improve accuracy and improve productivity and maintainability of the entire device.

[Brief description of drawings]

FIG. 1 shows a drive motor portion that constitutes a main part of an embodiment of the present invention, FIG. 1 (A) is a sectional view with a part thereof omitted, and FIG. 1 (B) shows an output shaft portion of the drive motor. FIG.

FIG. 2 is an explanatory view showing a spigot connection state with respect to a gear case of the drive motor in FIG.

FIG. 3 is an explanatory diagram showing the relationship between the drive motor in FIG. 1 and other components.

FIG. 4 shows an example of the small gear disclosed in FIG.
4A is a sectional view thereof, and FIG. 4B is a right side view of FIG. 4A.

FIG. 5 is an explanatory view showing an example of the work of mounting the pinion gear disclosed in FIG. 1;

FIG. 6 is an explanatory diagram showing an example of work when disengaging the spline connection of the small gear disclosed in FIG. 1;

7 is a front view showing an example of the pinion bolt disclosed in FIG. 1. FIG.

[Explanation of symbols]

 1 Drive Motor 1A Output Shaft 1b, 15a Inlay Part 1s Shaft Spline 3 Differential Gear Mechanism 5,7 Wheels 9 Reduction Gear Mechanism 11 Small Gear 11A Through Hole 11s Hole Spline 13 Counter Gear 15 Pinion Bolt as Bolt

Claims (2)

[Claims] 1. An electric vehicle comprising: a drive motor for an electric vehicle; and a reduction gear mechanism connected to an output stage of the drive motor and transmitting the output of the drive motor to wheels via a differential gear mechanism. In the drive device, the reduction gear mechanism is configured to include a small gear integrated with an output shaft of the drive motor and a counter gear that meshes with the small gear, and the small gear has the one end of the drive motor. For an electric vehicle, which is spline-coupled to the output shaft of the drive motor, and the pinion gear is bolted to the output shaft of the drive motor with a predetermined bolt through a through hole provided in a central shaft portion thereof. Drive. 2. The bolt is provided with a spigot portion at a central portion in a longitudinal direction thereof for fixing a state where the small gears and respective central axes of the output shafts of the drive motors coincide with each other. 1. The drive device for an electric vehicle according to 1.