JPH0326291B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a two-stage automatic transmission in a device that drives a load using an electric motor as a drive source.

In the case of a load that temporarily increases, for example, in the drive motor of the front window wiper device of a car, a large output motor is required to remove snow that has adhered to the front window while the car is stopped during snowfall. It becomes necessary.
Although the chances of such a situation occurring are small, it is unavoidable to employ a motor with a sufficiently large output to accomplish this. Therefore, during normal operation during rain,
The driving torque for the wiper is only 1 kilogram centimeter, but in order to guarantee operation even when an abnormal load is applied to the wiper, electric motors with an output torque 100 times higher are currently in use. .

In the above case as well, it is effective if the output torque can be increased using a reduction gear as necessary, since a relatively small output motor can be used.
Furthermore, in the case of a small electric vehicle, the device of the present invention can be used as a two-speed torque converter (automatic transmission). That is, a torque detection device is provided on the wheel,
When the required torque increases on an uphill slope, etc., the electric signal obtained from the torque detection device automatically changes the gear ratio to a higher gear ratio, allowing the vehicle to climb uphill.

When driving a load with an electric motor, it is often necessary to use an electric motor with a large output in order to cope with an occasional increase in load. Therefore, during normal operation, there is too much output, making it an extremely uneconomical solution in terms of size, cost, and efficiency.

The device of the present invention is characterized in that it can provide concrete means for eliminating the above-mentioned disadvantages and contradictions.

Next, details of the apparatus of the present invention will be explained with reference to FIG. 1 and subsequent figures.

FIG. 1 is for explaining the operating principle of the apparatus of the present invention. In FIG. 1, two gears 10 and 11 are attached to the output shaft 7a of an electric motor (not shown).
is fixed. Gears 9 and 9b of large and small diameters are integrated into a support shaft 9a provided on the main body, which is the driven side, and are rotatably supported. Furthermore, gears 9 and 10 are in mesh with each other.

A rotary shaft 1 is rotatably supported on bearings (indicated by symbols 2a and 3 in FIG. 2) provided on the main body, and a rotary ring that becomes the inner ring of the one-way clutch is mounted on the rotary shaft 1. 1a and gear 1b (indicated by dotted lines)
is fixed.

The one indicated by symbol 2 is the outer ring of the one-way clutch described above, and steel balls (sometimes steel rollers) 4a, 4b, and 4c are interposed between the inner ring 1a and the outer ring 2, and the outer ring It is configured to abut on slopes 3a, 3b, and 3c fixed to 2, respectively. Since this is a one-way clutch with the above configuration, when the inner ring 1a rotates counterclockwise, the inner and outer rings 1a rotate due to the steel balls and the slope.
When a and 2 are locked and the outer ring 2 is driven in the same direction, and the inner ring 1a rotates clockwise, it only rotates freely. The steel ball 5, the slope 6 fixed to the outer ring 8, and the inner ring 2 (which served as the outer ring in the one-way clutch described above) are further connected to one
It constitutes a directional clutch. Two more sets of members corresponding to the steel balls 5 and the slope 6 are provided and are interposed between the inner ring 2 and the outer ring 8 at an opening angle of 120 degrees, but they are omitted from the illustration. do not have.

A one-way clutch consisting of an inner ring 1a and an outer ring 2 is used as a first one-way clutch consisting of an inner ring 2 and an outer ring 8.
The direction clutch is referred to as a second one-way clutch.

Gear 1b and gear 11 are in mesh with each other. The outer ring 8 is provided with a gear 8a, and the gear 8a and the gear 9b mesh with each other. When the output shaft 7a rotates in the clockwise direction of the arrow (normal rotation direction), the gear 1b and the inner ring 1a rotate counterclockwise, so the outer ring 2 also rotates in the same direction. The output shaft of the outer ring 2 (designated as 12 in FIG. 2) also drives the load in the same direction. At this time, the gears 9 and 9b rotate counterclockwise and the outer ring 8 rotates clockwise, but the locking by the steel balls 5 and slope 6 is not performed, and the outer ring 8 only rotates freely. When the electric motor is reversed and the output shaft 7a is rotated counterclockwise (reverse direction), the gear 1b and the inner ring 1a rotate clockwise, so the first one-way clutch does not lock and rotates the inner ring. 1a is idle. Also, since the gears 9 and 9b are driven clockwise and the outer ring 8 is driven counterclockwise, the second one-way clutch causes the inner ring 2 (which may also be considered the outer ring 2) to rotate in the same direction. Drives connected loads in the same direction.

As understood from the above explanation, the output shaft 7
The load is driven in the same direction by either forward or reverse rotation of a. However, since there are two torque transmission systems, the gear ratios are different. In this embodiment, since the torque transmission system via the gears 9 and 9b has a larger reduction ratio, it is possible to drive the load with a larger torque.

What is shown in FIG. 2 is a drawing of the mechanism shown in FIG. 1 viewed from the direction of arrow A. However, considering practicality,
The first and second one-way clutches are modified. Components with the same symbols as in FIG. 1 are the same members, so their explanations will be omitted.

In FIG. 2, the rotating shaft 7a of the electric motor 7 has
Gears 10 and 11 indicated by dotted lines are fixed.

A rotating shaft 1 is rotatably supported by bearings 2a and 3 provided on the main body, and an inner ring 1a and a gear 1b, which are integrated into one body, are fixed to the rotating shaft 1. The outer ring 2 and the inner ring 1a constitute a first one-way clutch. The outer ring 2 is loosely fitted onto the rotating shaft 1, and the right side thereof is cylindrical and forms an output shaft 12 for driving a load. A load, such as the wheels of an electric vehicle, is driven from the output shaft 12 by a well-known torque transmission mechanism.

The outer ring 2 is an inner ring, and the outer ring 8 forms a second
A directional clutch is configured.

What is indicated by a dotted line 9 is a gear 9 having the same symbol in FIG. 1, and the gear 9b meshes with the gear 8a of the outer ring 8. The gear 9b is omitted and not shown.

Gears 11 and 1b and gears 10 and 9 are in mesh with each other.

With the above configuration, the operation is exactly the same as that described in FIG. 1, and the output shaft 12 is driven at different reduction ratios by forward and reverse rotation of the electric motor 7.

The device of the present invention can drive the load using a group of gears with different reduction ratios using the forward and reverse rotation of the electric motor 7 as a signal, so the mechanism is simplified, small, lightweight, and
This has the effect of being able to drive a load at a low cost and with different reduction ratios without failure. Particularly in the case of automatic gear shifting, it has the feature of providing an effective technical means.

Next, referring to FIG. 6a, the forward/reverse circuit of the DC motor 7 will be explained.

In FIG. 6a, symbols 13a and 13b are power supply terminals. Changeover switch 14 that operates in conjunction with
a and 14b, the actuator is moved to the left side (in the illustrated position, the electric motor 7 rotates forward), the neutral position (the position where the electric current to the electric motor 7 is cut off), and the right side by a manual knob (not shown). 3 in position (motor 7 reverses)
It is configured so that it can be switched between two positions.
The electric motor 7 is a DC motor and has the same symbol as in FIG. The case of a drive motor for a windshield wiper of an automobile will be explained as an example.

When the actuator is moved to the illustrated position using the manual knob, the electric motor 7 rotates in the normal direction, so that the wiper device acting as a load operates normally and the window is cleaned, as explained in FIG. 1.

If the wiper does not operate due to snow accumulation while stopped, use the manual knob to turn the changeover switch 14a,
When the actuator 14b is switched to the right side, the electric motor 7 is reversed. Therefore, the torque of the output shaft 12 in FIG. 2 increases, increasing the driving force of the wiper and removing snow. When the elimination is completed, the changeover switch 14
When a and 14b are restored, normal operation of the wiper device can be restored.

As described above, there is no need to increase the rated output of the motor 7 in order to cope with a temporary increase in load, and this has the effect of providing an effective means for downsizing the motor serving as a drive source.

Motor 7 is a brushless motor (semiconductor motor)
In this case, known means are used for forward and reverse rotation.

Also, a well-known transistor bridge circuit can be used in place of the changeover switches 14a and 14b.

In the embodiments shown in FIGS. 1 and 2, the same effect can be obtained by replacing the torque transmission systems of the gears 10, 9 and the gears 1a, 11 with belt transmission systems using pulleys.

The device shown in FIG. 6a is an effective means when applied to the following cases.

When starting equipment driven by electric motors in cold regions, the viscosity of the lubricating oil increases, increasing the load, making it difficult to start, and potentially causing burnout of the electric motor. be. Even in such a case, the above-mentioned drawbacks can be eliminated by reversing the electric motor when the load is large and applying the device of the present invention.

In the two examples described above, the load torque is also detected, and the electric switch 14 is activated based on this detection output.
Adding a device to operate a and 14b is an effective technical means. Further, if the load torque detection device 13 is used as a device for detecting the driving torque of a load, such as a wheel of a small electric vehicle, the following operation can be performed automatically. When the required torque increases on an uphill slope or when starting, a detection output is obtained from the torque detection device 13, and this output causes the electric switches 14a and 14b to be switched to increase the output torque, and when the required torque decreases, the detection is performed. It can be configured such that the output disappears and the electric switches 14a, 14b are restored. By such means, an automatic transmission device can be obtained.

What is shown in FIG. 6b is an example in which an induction motor is used as the drive source.

In FIG. 6b, symbol 16 is a rotor of an induction motor, and field coils 17a and 17b are supplied with alternating current from an alternating current power source 14. In FIG. capacitor 1
8 is for creating a phase difference between the currents flowing through the field coils 17a and 17b.

A device designated by symbol 19 containing two sets of electrical contacts is
This is an electrical contact of a relay that is activated by energizing an excitation coil. When the excitation coil is not energized, the induction motors 16, 17a, 17b (hereinafter indicated only by the symbol 16) rotate in the normal direction, and when the excitation coil is energized, the electric contacts 19 are switched to rotate in the reverse direction.

The induction motor 16 corresponds to the motor 7 in FIG. The relay is activated by the output of the device indicated by symbol 13, and the electric switch 19 is activated, so that the operation and effect are exactly the same as in the case of FIG. 6a.

As mentioned above, there is no need to use a large output motor for the initial large load for a short time.
Moreover, since the most efficient electric motor can be selected during normal operation, it has the feature of providing an effective means.
Other embodiments for achieving the same purpose are shown in Figures 3 and 4.
As shown in the figure. Next, the details will be explained.

The input rotating shaft 7a is driven by the electric motor 7 as in FIG.

FIG. 4a shows a well-known planetary gear system in which a sun gear 23 is driven by a rotating shaft 7a, and support shafts 22a, 22b provided on a carrier 20,
Gears 21a, 21b, and 21c are supported by 22c. Ring gear 27a and sun gear 23 are meshed with planetary gears 21a, 21b, and 21c. The cross section indicated by dotted line B is shown in FIG. Items with the same symbol are shown with the same parts.

In FIG. 3, the carrier 20 has a rotating shaft 7a
It fits loosely into the main body and is fixedly supported by the main body. A sun gear 23 is fixed to the rotating shaft 7a, and a rotating ring 24 is also fixed at the same time. The rotating wheel 25 is
It is loosely fitted to the rotating shaft 7a and the rotating ring 24. On the right side of the rotating ring 25, a coaxial output shaft 25a is integrally formed on the right extension of the rotating shaft 7a.
A load (not shown) is driven by the output of 5a. The rotating wheels 24 and 25 form a one-way clutch via the steel ball 26a. This detail is shown with the same symbols in FIG. 4b. That is, steel balls 26a, 26b, 2
6c and the slope in contact with the inner ring 24 and the outer ring 25 form a one-way clutch, and the outer ring 25 is driven only when the inner ring 24 rotates counterclockwise.

Returning to FIG. 3, the rotating ring 27 provided with the ring gear 27a is loosely fitted to the outside of the rotating ring 25 and is rotatably supported. Details of this will be explained next in conjunction with FIG. 4b.

In FIG. 4b, steel balls 28a, 2
Since 8b and 28c are in contact with the slope of the outer ring 27, the inner ring 25 is driven in the same direction only when the outer ring 27 rotates counterclockwise.

As can be seen from the above explanation, the rotating wheels 24, 25
The rotating wheels 25 and 27 constitute first and second one-way clutches, respectively. When the rotating wheel 7a rotates in the counterclockwise direction (normal rotation), the rotating wheel 25 is driven in the same direction, so the output shaft 25a is also rotated in the same direction. At this time, the rotation ratio is 1:1 with respect to the input rotating shaft 7a. Also, at this time, the planetary gears 21a, 21b, 2 in figure a
The rotating wheel 27 is driven clockwise by 1c. However, the rotating wheels 27 and 25 are sliding.

Next, when the rotating shaft 7a is reversed clockwise, the torque transmission to the rotating wheel 25 is cut off. However, since the rotating wheel 27 is driven counterclockwise by the planetary gears 21a, 21b, and 21c, the rotating wheel 25, that is, the output rotating shaft 25a, is driven in the same direction via the second one-way clutch. In this case, the sun gear 23, planetary gears 21a, 21
The output rotating shaft can be driven at a free reduction ratio depending on the ratio of the diameters of the ring gear 27a, 21c, and the ring gear 27a.

In this case, the rotation speed of the rotation wheel 25 is in the opposite direction to the rotation speed of the rotation wheel 24 in the clockwise direction, so that only sliding occurs between the two.

As can be seen from the above explanation, this embodiment has exactly the same effect as the previous embodiment. A feature of this embodiment is that the input and output axes are on the same straight line.

Next, FIG. 5 will be explained. The device shown in FIG. 5 rotates the motor in reverse when the load 30 exceeds a set value, and rotates the motor in the normal direction when the load 30 becomes smaller than the set value.

A lever 31 is rotatably supported on a support shaft 31a provided on the main body, and a gear 32 is also rotatably supported at the same time. The load 30 is driven by a gear 32 via a required torque transmission system.

A gear 33 is attached to a support shaft 33a provided on the lever 31.
are supported and mesh with gears 32 and 34.

A rotating shaft 34a fixed to the gear 34 is provided to rotate synchronously with the rotating shaft 12 in FIG. 2 or the rotating shaft 25a in FIG. 3. Therefore, the second and third
The device shown is fixed to a lever 31. For example, the gear 34 is fixed to the rotating shaft 12 shown in FIG. In the case of the device shown in FIG. 3, the gear 34 is fixed to the rotating shaft 25a. The rotation direction of the gear 34 is counterclockwise. load 30
When the load is normal, the lever 31 receives clockwise torque due to the reaction of the load 30, but the spring 35 applies counterclockwise torque to the lever 31, and the lever 31 is Since its rotation is restrained by the restraining member 36a, the lever 31 is stopped and held at the illustrated position, and the load 30 is therefore driven.

When the magnitude of the load 30 increases and exceeds a set value, the lever 31 is rotated clockwise against the elastic force of the spring 35, and comes into contact with the restraining member 36b and stops. Therefore, lever 3
1, the electric switch 37 is closed,
The output energizes the monostable circuit 37a, which energizes the excitation coil 19a of the relay only for a predetermined period of time via the OR circuit 37b. The electrical contacts 19 in FIG. 6b are therefore switched and the motor (motor 16 in FIG. 6) is therefore reversed, so that the output torque of the gear 34 is increased to accommodate the increased load torque, as described above. The corresponding output will be the load 30
can be driven. In the process described above, the electric motor 16 will stop once before entering reverse rotation. Therefore, the lever 31 returns to its original position after receiving the counterclockwise torque, but as described above, the state of the reverse rotation command for the electric motor 16 is not changed due to the output of the monostable circuit 37a.
is reversed, the lever 31 rotates clockwise again, and the electric switch 37 is closed again. Therefore, even if the output of the monostable circuit 37a is cut off after a predetermined period of time, the output of the electric switch 37 will cause the output to continue through the OR circuit 37b. Subsequently, the excitation coil 19a is energized, the electric motor 16 is reversed, and the load 30 can be driven in response to the increased load torque.

When the load torque decreases to a normal value, the lever 31 returns, the electric motor 16 returns to normal rotation, and the load 30 is driven.

As explained above, the device shown in FIG. 5 serves as an overload detection device, and when the load increases, the motor 1
6 is reversed to drive the increased load, and when the motor 16 reaches a normal value, the electric motor 16 returns to normal rotation and can drive the load. Therefore, the device shown in FIG. 5 is a load torque detection device 13.
(Illustrated in FIG. 6b).

In the case of the load torque detection device shown in FIG. 6a, since a relay is not used, the electric switch 14
When the actuators of the electric switches 14a and 14b are pressed by the lever 31, oil dampers are provided on the actuators of the electric switches 14a and 14b so that even if the lever 31 is temporarily retracted, the actuators of the electric switches 14a and 14b do not return immediately. It needs to be attached. That is, the forward/reverse electric switches 14a, 14b of the electric motor 7 require a delay device. As mentioned above, when the electric switches 14a and 14b are transistor bridge circuits,
An electronic delay circuit is used.

In order to achieve the same purpose as the device shown in FIG.
It is also possible to construct a device having the same purpose as that shown in FIG. 5 by using a ring gear 2 and attaching a spring 35 and restraining members 36a and 36b to the carrier of the planetary gear.

Other well-known delay circuits may be used in place of the monostable circuit 37a of FIG. 5.

As explained above, according to the apparatus of the present invention, the object stated at the beginning is achieved and the effect is remarkable.

[Brief explanation of the drawing]

1 and 2 are explanatory diagrams of the apparatus of the present invention, FIG. 3 is an explanatory diagram of another embodiment, and FIG. 4 is an explanatory diagram of the device of the present invention.
FIG. 3 is an explanatory diagram of a part of the device, FIG. 5 is an explanatory diagram of a load torque detection device, and FIG. 6 is a control circuit diagram of the device of the present invention. 2a, 3... Bearing, 1, 7a... Rotating shaft, 4a, 4
b, 4c, 5...Steel ball, 3a, 3b, 3
c, 6...Slope, 1a...Inner ring, 2...Inner/outer ring, 8
... Outer ring, 10, 11, 9, 9b, 8a, 1b... Gear, 7... Electric motor, 9a... Support shaft, 12... Output shaft, 1
3a, 13b...Power terminal, 14a, 14b, 19
...Forward/reverse switching electric switch, 13...Load torque detection device, 16...Rotor of induction motor, 17a,
17b... Two-phase field coil, 18... Capacitor,
14...AC power supply, 25a...output shaft, 20...carrier, 21a, 21b, 21c...planetary gear,
22a... Support shaft, 23... Sun gear, 24... Inner ring, 2
5...Inner ring/outer ring, 27...Outer ring, 27a...Ring gear, 28a, 28b, 28c, 26a, 26b,
26c... Steel ball, 34, 33, 32... Gear, 31... Lever, 31a, 33a, 34a... Support shaft, 36a, 36b... Suppression member, 35... Spring, 37... Electric switch, 37a... Monostable circuit,
19a...excitation coil.

Claims (1)

[Claims] 1. An electric motor as a drive source, an electric circuit that rotates the electric motor in forward or reverse rotation, first and second rotating wheels driven by the electric motor, and a main body as a driven side. an output rotating shaft 12, 25a rotatably supported by the output rotating shaft 12, 25a; a load driven by the output rotating shaft 12, 25a; and a first one-way clutch connecting the output rotating shaft 12, 25a. a third rotating wheel that drives only in a predetermined direction; a fourth rotating wheel that drives the output rotating shaft 12, 25a only in the predetermined direction via a second one-way clutch; At this time, the first rotating wheel drives the third rotating wheel in the predetermined direction via the first reduction mechanism, and the rotational forces of the second and fourth rotating wheels are equal to the output. a mechanism that does not transmit transmission to the rotating shafts 12, 25a, and a second rotating wheel when the electric motor rotates in reverse, through a second reduction mechanism having a larger reduction ratio than the first reduction mechanism; A mechanism for driving the rotating wheels in the predetermined direction and not transmitting the rotational forces of the first and third rotating wheels to the output rotating shafts 12, 25a; , a device that detects the torque of the load and generates a detection signal when the torque of the load increases; The electric motor is reversed to drive the output rotating shafts 12, 25a via the second one-way clutch, and when the torque of the load decreases beyond a set value, the detection signal causes the electrical circuit to be connected. and a device for driving the output rotating shafts 12, 25a via the first one-way clutch to rotate the electric motor in the normal direction.