JPS63314101A - Electric braking device - Google Patents

Abstract

PURPOSE:To realize durable structure, low noise, and strong braking, by applying a speed-variable rotating field positively or negatively from an inverter circuit, to a squirrel-cage polyphase induction machine connected to the main shaft of an internal combustion engine. CONSTITUTION:By the main shaft of an internal combustion engine 1 mounted on an automobile, the rotor section of a squirrel-cage polyphase induction machine 2 is rotationally driven. At the time of braking a car body, the exciting voltage of frequency accommodated to the induction of the rotating field of a rotational speed lower than that of the rotor section of the squirrel-cage polyphase induction machine 2 is applied to the stator winding of the squirrel- cage polyphase induction machine 2 via an inverter circuit 4 through a secondary battery 3. As a result, the mechanical energy of a rotary system is converted to electrical energy, and the secondary battery 3 is charged with this electrical energy. By an inverter controlling circuit 5, the degree of braking is controlled according to the driving of the automobile.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electric braking device for a motor vehicle. In particular, the present invention relates to an electric braking device including a rotating machine connected to a driving means for driving a main shaft or an axle of an internal combustion engine.

〔overview〕

The present invention provides an electric braking system for an automobile including a rotating machine, in which a squirrel-cage multiphase induction machine is used for the rotating machine, and a rotating magnetic field whose speed is variable in positive or negative direction is applied to the squirrel-cage multiphase induction machine from an inverter circuit. This allows this squirrel cage multiphase induction machine to operate as a generator and perform electrical braking.

[Conventional technology]

Advances in internal combustion engines, especially improvements in supercharging technology and the development and practical use of heat-resistant materials, have led to smaller internal combustion engines.As internal combustion engines become smaller, the effectiveness of the exhaust brake or engine brake becomes smaller. It became necessary to use a retarder in addition to the friction braking device installed on the wheels.
An auxiliary braking device is required to cancel the acceleration due to the slope when descending and to decelerate to a predetermined speed during the initial process of high-speed braking. Attempts have been made to apply a generator with an inductor type structure.

[Problem that the invention seeks to solve]

The eddy current method traditionally used as a retarder is
The structure is robust and can withstand external forces caused by irregular vibrations of the wheels caused by uneven road surfaces, etc. However, all the mechanical energy that would be consumed during braking is converted into thermal energy and released into the atmosphere. , that energy cannot be regenerated. This runs counter to the recent trend of demanding greater savings in fuel consumption associated with vehicle travel. Furthermore, it is necessary to mount a device with a large heat capacity on the vehicle for heat dissipation, which increases the size of the device.

On the other hand, it has been confirmed that directly connecting an inductor type photoelectric machine to the main shaft of an internal combustion engine is effective as an auxiliary device for engine braking or exhaust braking. In addition, this structure converts the mechanical energy that should be consumed during braking into electrical energy, regenerates this electrical energy into the secondary battery, and uses the regenerated electrical energy, for example, in a starter device or other installed equipment. I also found out that it can be used. However, this inductor type photoelectric machine generates a large magnetic noise when generating electric power, and further research is required to obtain a practical device that can be used satisfactorily by automobile users.

Furthermore, in inductor-type optoelectronic machines, if the gap between the stator and rotor is not made as small as possible, magnetic leakage will occur, increasing magnetic resistance and reducing efficiency. It was also found that the machining precision needed to be considerably high, which would pose a significant obstacle to mass production.

The present invention aims to eliminate such drawbacks, and provides an electric braking device that has a robust structure suitable for mounting on an automobile, can realize strong braking with low noise, and is suitable for mass production.

[Means for solving problems]

The present invention provides an electric braking device including a rotating machine directly connected to the main shaft of an internal combustion engine that drives an axle of an automobile, wherein the rotating machine is a squirrel-cage multiphase induction machine, and a rotating magnetic field is applied to the squirrel-cage multiphase induction machine. It is characterized by being equipped with an electric means for giving.

The rotor part of the squirrel cage multiphase induction machine is attached to the flywheel fitted into the main shaft of the internal combustion engine, and the stator part is attached to the inside of the flywheel housing, or the squirrel cage multiphase induction machine is attached to the flywheel fitted into the main shaft of the internal combustion engine. The structure can be attached to the front end of the

The present invention also provides an electric braking device including a rotating machine coupled to a main shaft of an internal combustion engine that drives an axle of an automobile, wherein the rotating machine is a squirrel-cage multiphase induction machine; The squirrel cage multiphase induction machine is characterized in that it is equipped with an electric means for applying a rotating magnetic field, and is directly connected to a drive shaft between a transmission device and a rear axle.

The squirrel cage polyphase induction machine can be mounted at the rear of the transmission, at the inlet of the rear axle, or on the propeller shaft between the transmission and the rear axle.

[Effect]

By directly connecting the rotor section of the squirrel-cage multiphase induction machine to an internal combustion engine or drive means, and electrically controlling the rotation speed of the rotating magnetic field generated by the stator section, it is possible to perform braking that matches the running of the vehicle. can.

〔Example〕

An embodiment of the present invention will be described below based on the drawings.

FIG. 1 is a block configuration diagram showing the electrical configuration of this embodiment device. FIG. 2 is a schematic diagram showing the position where the squirrel cage multiphase induction machine used in this embodiment device is installed. FIG. 3 is a mechanical configuration diagram showing the mechanical structure of this squirrel-cage multiphase induction machine, which is partially cut away along a plane along the axis of the main shaft of the engine.

FIG. 4 is a mechanical configuration diagram showing a part of a cross section taken along arrow IV-rV in FIG. 3. FIG.

As shown, the elements of the rotor section are mounted on the flywheel and the elements of the stator section are attached to the flywheel housing.

Since this rotating machine is a squirrel-cage multiphase induction machine, the structure of the rotor section is extremely simple and there is no sliding structure. Also,
Compared to the conventional inductor type structure, the magnitude of magnetic resistance between the rotor part and the stator part does not greatly affect braking performance, so a larger gap can be provided. That is, in the apparatus of the present invention, the machining accuracy regarding the gap between the rotor part and the stator part is looser than that of an inductor type generator.

The electrical configuration of this embodiment device will be explained based on FIG. 1. This embodiment device includes a squirrel cage multiphase induction machine 2 directly connected to an internal combustion engine 1, a secondary battery 3, and converts the DC voltage into an AC voltage with a frequency suitable for inducing a rotating magnetic field with a rotation speed lower than the shaft rotation speed of the squirrel-cage polyphase induction machine 2, and applies this to the squirrel-cage polyphase induction machine 2; The inverter circuit 4 includes an inverter circuit 4 that converts AC power from the squirrel cage multiphase induction machine 2 into DC power, and an inverter control circuit 5 that sets the frequency of the AC side voltage of the inverter circuit 4.

A rotation sensor 6 is attached to this squirrel cage multiphase induction machine 2, and a signal from this rotation sensor 6 is given to an inverter control circuit 5.

Further, a resistor 7 is connected to the secondary battery 3 via a switch circuit 6, and a capacitor 8 is connected to the output of the inverter circuit 4.

Next, the squirrel cage multiphase induction machine 2 used in this example device
The mechanical structure will be explained based on FIGS. 2 to 4.

This squirrel cage multiphase induction machine 2 is installed inside a flywheel device 10 fixed between an internal combustion engine 1 and a transmission device 20, as shown in FIG. That is, as shown in FIG. 3, the stator core 11, the stator winding 12 inserted into the coil groove of the stator core 11, and the lead wire are placed in a space surrounded by the flywheel housings 15 and 16 of the flywheel device 10. 13 as main elements, a rotor core 21, a squirrel-cage winding 22 inserted into the coil groove of the rotor core 21, and a retaining ring fitted to the end ring 23 of the squirrel-cage winding 22. A rotor section having 24 as a main element is housed therein. The stator core 11 is fitted into the stator ring 14, and the stator ring 14 is connected to the flywheel housing 15 and 1.
6. On the other hand, the rotor core 21 is fixed to the outer edge of a flywheel 25 that is rotationally driven by the main shaft 26 of the internal combustion engine 1 .

Next, the electrical operation of this embodiment device will be explained based on FIG.

- The rotor section of the squirrel cage multiphase induction machine 2 is rotationally driven by the main shaft of the internal combustion engine 1 mounted on the automobile.

When the mechanical energy of this rotating system is released or absorbed to brake the running of the vehicle, the rotating magnetic field with a rotation speed lower than the rotation speed of the rotor part of the squirrel cage multiphase induction machine 2 is applied to the squirrel cage multiphase induction machine. An excitation voltage of a frequency suitable for inducing the stator winding of the squirrel cage multiphase induction machine 2 is applied from the secondary battery 3 to the stator winding of the squirrel cage polyphase induction machine 2 via the inverter circuit 4. As a result, the mechanical energy of the rotating system is converted into electrical energy, and the secondary battery 3 is charged with this electrical energy.

The inverter control circuit 5 is connected to the inverter circuit 4.
It includes a device that controls the degree of braking depending on the driving of the vehicle.

When temporarily generating a large braking force while driving a car, it is difficult to regenerate all the electrical energy generated from the squirrel cage multiphase induction machine 2 to the secondary battery 3.
It is dissipated as heat energy by a resistor 7 via a switch circuit 6. The switch circuit 6 includes a circuit that monitors the terminal voltage of the secondary battery 3 and automatically connects a resistor 7 across the secondary battery 30 when this terminal voltage exceeds a predetermined value.

FIG. 5 is an electric circuit diagram showing a more detailed example of the apparatus according to the present invention.

In this embodiment, the squirrel cage polyphase induction machine 2 has three phases. The secondary battery 3 and the squirrel cage multiphase induction machine 2 are coupled by an inverter circuit 4 . A negative terminal E2 of the secondary battery 3 is connected to the common potential of the vehicle.

This inverter circuit 4 includes switch elements Qa, QbSQc connected between each phase terminal of the squirrel cage multiphase induction machine 2 and the positive and negative terminals of the secondary battery 3.

Including Qd SQe and Qf. This switch element Qa
.

Qb, Qc, Qd SQe SQf are each composed of a transistor and a diode connected in parallel in the opposite direction between the collector and emitter of the first transistor. Furthermore, this inverter circuit 4 includes the above-mentioned switch elements Qa SQb, Qc, and Qd.

It includes an opening/closing control signal generation circuit PWM that provides opening/closing control signals to the control electrodes Qe and Qf.

This inverter circuit 4 was specially designed for use in automobiles in order to test the present invention, but the basic technology is well known. In other words, the technique of controlling the rotating magnetic field of a squirrel-cage multiphase induction machine according to the rotation of its rotor is an application of the technique applied to, for example, AC elevators or cranes.

A rotation sensor 6 is attached to the squirrel cage multiphase induction machine 2 (or internal combustion engine 1) to electrically detect the rotation of its main shaft. The pulse signal output from this rotation sensor 6 is converted into a digital-to-analog conversion circuit DA.

This results in an analog signal representing the rotational speed. This analog signal is connected to one input of the operational amplifier AMP, and is added or subtracted according to the control reference corresponding to the amount of slip generated from the digital-to-analog conversion circuit DA2 and its polarity. The output of this operational amplifier AMP is given to the above-mentioned switching control signal generation circuit PWM as an output frequency control signal of the inverter circuit 4. That is, the squirrel cage polyphase induction machine 2, the rotation sensor 6, the digital-to-analog conversion circuit DA1, the operational amplifier AMP, and the inverter circuit 4 form a negative feedback servo control loop.

A control reference corresponding to the amount of slip is added to this negative feedback servo control loop, and the signals necessary for the control means that generate this amount of slip will be explained. This control means is composed of various circuits located at the lower left of FIG. 5, including a microprocessor CPU, an interface circuit 0, a torque control circuit Tq1, switches A1 and A2 that are linked to the accelerator pedal of the automobile, and a transmission circuit 0, which is connected to the accelerator pedal of the automobile. Switches N1 and N2, which indicate the neutral position of Yon, and switches CI+ and Cβ2, which are also linked to the clutch pedal,
It includes a first switch Sls operated by the driver, a second switch S2 operated by the driver, a switch KS interlocked with the starting key switch of the internal combustion engine, and a digital-to-analog conversion circuit D A 2.

The switch S3 is a conventional exhaust brake switch, and is connected to the exhaust brake circuit Ex.

The first switch S1 is a switch for instructing auxiliary acceleration, and the second switch S2 is a switch for instructing electric braking. This first switch S.

In this embodiment, the second switch S2 is designed to be operated by one operating lever β provided on the shaft of the handle, as shown in FIG. This operating lever β is OF
In the F position, both switches SI and S2 are open, and when the acceleration position is entered, the switch SI is closed.

Further, there are four braking positions, each of which is configured such that a plurality of contacts shown in the switch S2 are closed in sequence. Four positions of braking allow the driver to adjust the degree of electrical braking.

When the operating lever β is placed in the acceleration position, the degree of acceleration is determined by the amount of depression of the accelerator pedal.Accelerator pedal depression information is given to the terminal T1 in FIG. It was configured to send a signal to E0.

Approximately 100
It was found that it is possible to generate a braking force exceeding the horsepower, and as for the driving force, tens of horsepower can be obtained depending on the performance of the secondary battery 3, and it is possible to design a sufficiently practical device. In this embodiment, the rotor of the squirrel cage multiphase induction machine 2 is mounted on the flywheel of the internal combustion engine 1, and the diameter of the flywheel housing is about 700 mrn.

Among the parts constituting the control system of the embodiment shown in FIG. 5, the inverter circuit 4 and the secondary battery 3 are large. The secondary battery 3 is equivalent to or slightly larger than those conventionally installed in automobiles, and can be used practically. Regarding the inverter circuit 4, the switch elements Qa SQb.

Although the volume of Qc SQd, Qe, and Qf is large, the experimentally manufactured device generates a braking force of approximately 150 horsepower, has a total volume of approximately 80 liters, and can be placed sufficiently under the body of a medium-sized truck. did it. There is still plenty of room for this volume, and further research will be conducted on how to make it smaller. For example, inverter circuit 4
is composed of static electrical components without moving parts, so multiple switch elements Qa, Qb, Qc
It is possible to disperse and arrange SQd SQe and Qf at different positions in one automobile, and thereby it is possible to design and manufacture a configuration that is sufficiently practical for various automobiles.

In addition, it was found that the driving performance was not significantly different from the conventional exhaust brake operation, and that sufficient practical driving performance could be achieved.

Since the rotating machine of the device of the present invention is a squirrel cage multiphase induction machine,
The structure of the rotor part is simple, robust, and lightweight.
No friction parts such as brushes are used. Furthermore, the gap between the rotor and stator can be set larger than that of conventional inductor type.
Therefore, the machining accuracy during manufacturing is relaxed and mass productivity is excellent.

Additionally, since the rotor is squirrel-cage, there is almost no magnetic noise generated from the rotor side, and noise from the stator side is also significantly lower than that of conventional inductor types.

In the above example, the squirrel cage multiphase induction machine is a three-phase one, but the present invention can generally be implemented in a similar manner with a multiphase induction machine. By increasing the number of phases, the current per phase can be reduced, which is advantageous in applications such as small automobiles in which the components of the inverter circuit are distributed in various parts of the vehicle.

In the electric braking device according to the embodiment of the present invention described above, the rotor part of the squirrel cage multiphase induction machine 2 is attached to the flywheel fitted into the main shaft of the internal combustion engine 1, and the stator part is attached to the inside of the flywheel housing. However, the mounting position of the squirrel cage multiphase induction machine 2 is not necessarily limited to the flywheel and the flywheel housing.

Some examples are shown below. Fig. 7 shows a structure in which the squirrel-cage multiphase induction machine 2 is attached to the front end of the internal combustion engine 1, which has the drawback that it cannot be mounted on a conventional chassis.
This has the advantage of not requiring a crank torsional damper to resist and damp the torsional vibration of the crankshaft.

FIG. 8 shows a structure in which the squirrel-cage multiphase induction machine 2 is attached to the rear of the transmission device 20. It may be disconnected by a clutch and the transmission device 20 (not shown), and is not integrated with the internal combustion engine 1. However, it has the advantage that it is integrated with the rotation of the axle and can apply braking even when separated from the internal combustion engine 1.

In addition, FIG. 9 shows that the squirrel cage multiphase induction machine 2 is connected to the rear axle 40.
This figure shows a structure installed at the inlet of the internal combustion engine 1, which may be disconnected by a clutch and transmission device 20 (not shown) like the embodiment shown in FIG. 8, and is not integral with the internal combustion engine 1. The mounting structure of No. 1 is exactly the same as the conventional device and does not require any changes.

Furthermore, FIG. 10 shows a structure in which the squirrel cage multiphase induction machine 2 is attached to the propeller shaft 30 between the transmission device 20 and the rear axle 40, similar to the embodiments shown in FIGS. 8 and 9. Although it may be disconnected by a clutch and transmission device 20 (not shown) and is not integrated with the internal combustion engine 1, it has the advantage of a good space factor and the ability to mount a large rotating machine.

In this way, even if the mounting position of the squirrel-cage multiphase induction machine 2 changes, its configuration and operation are exactly the same as described above, and the same effects can be obtained.

〔Effect of the invention〕

As explained above, compared to conventional eddy current type retarders and inductor type optoelectronics, the structure is smaller and more robust, and the gap between the stator core and rotor core can be larger, making it easier to manufacture. The accuracy is moderate, which is extremely advantageous for mass production.

Furthermore, compared to inductor-type photoelectric machines, there is no influence of magnetic leakage, and the power generation efficiency is extremely high, allowing strong braking force to be obtained and energy to be used effectively.

In addition, compared to inductor-type photoelectric machines, the induction generator of the present invention produces extremely low noise during braking (and has the effect of not causing discomfort to the vehicle driver. This is due to the simple structure of the rotor part. This may be due to the fact that, in the test device prototyped by the inventors, by using this squirrel-cage multiphase induction machine, a device with low noise enough to be put to practical use was obtained.

Further, since the present invention uses a squirrel-cage multiphase induction machine, there is no need for a current collector that requires a brush, and there is an excellent effect of saving time and effort for maintenance.

[Brief explanation of drawings]

FIG. 1 is a block configuration diagram showing the electrical configuration of an embodiment of the present invention. FIG. 2 is a schematic diagram showing the mounting position of the squirrel cage multiphase induction machine used in the embodiment of the present invention. 3 and 4 are mechanical configuration diagrams showing the structure of a squirrel cage multiphase induction machine used in an embodiment of the present invention.゛FIG. 5 is a more detailed electrical circuit diagram of an embodiment of the present invention. FIG. 6 is a perspective view of the driver's seat according to the embodiment of the present invention. FIG. 7 is a configuration diagram in which a device according to an embodiment of the present invention is installed at the front end of an internal combustion engine. FIG. 8 is a configuration diagram in which a device according to an embodiment of the present invention is installed at the rear of a transmission and transmission device. FIG. 9 is a configuration diagram in which a device according to an embodiment of the present invention is installed at the entrance of a rear axle. FIG. 10 is a configuration diagram in which a device according to an embodiment of the present invention is mounted on a propeller shaft between a transmission device and a rear axle. 1... Internal combustion engine, 2... Squirrel cage multiphase induction machine, 3...
- Secondary battery, 4... Inverter circuit, 5... Inverter control circuit, 6... Rotation sensor, 7... Resistor,
DESCRIPTION OF SYMBOLS 10... Flywheel device, 11... Stator core, 12... Stator winding, 13... Lead wire, 14
...Stator ring, 15.16...Flywheel housing, 20 Transmission device, 21...
・Rotor core, 22... Squirrel cage winding, 23... End ring, 24... Retaining ring, 25... Flywheel, 26... Main 1dl, 30... Propeller shaft, 40... ...Rear axle.

Claims (1)

[Claims] 1. In an electric braking device including a rotating machine directly connected to the main shaft of an internal combustion engine that drives an axle of an automobile, the rotating machine is a squirrel-cage multiphase induction machine, and the squirrel-cage multiphase induction An electric braking device characterized by being equipped with an electric means for applying a rotating magnetic field to a machine. 2. The electric braking device according to claim 1, wherein the rotor portion of the squirrel cage multiphase induction machine is attached to a flywheel fitted into the main shaft of the internal combustion engine. 3. The electric braking device according to claim 2, wherein the stator portion of the squirrel cage multiphase induction machine is mounted inside a flywheel housing of an internal combustion engine. 4. The electric braking device according to claim 1, wherein the squirrel cage multiphase induction machine is installed at the front end of the internal combustion engine. 5. In an electric braking device including a rotating machine coupled to the main shaft of an internal combustion engine that drives the axle of an automobile, the rotating machine is a squirrel-cage multiphase induction machine, and a rotating magnetic field is applied to the squirrel-cage multiphase induction machine. An electric braking device comprising an electric means, wherein the squirrel cage multiphase induction machine is directly connected to a drive shaft between a transmission device and a rear axle. 6. The electric braking device according to claim 5, wherein the squirrel cage multiphase induction machine is installed at the rear of the transmission device. 7. The electric braking device according to claim 5, wherein the squirrel cage multiphase induction machine is installed at the entrance of the rear axle. 8. The electric braking device according to claim 5, wherein the squirrel cage multiphase induction machine is mounted on a propeller shaft between the transmission device and the rear axle.