JPH0971244A - Carrier with power assist function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an immovable condition or a dangerous condition from being generated when a carriage is going to be operated by a powerless person such as an old man or a woman. SOLUTION: This carriage with power assist function furnishes a driving wheel 1; an electric motor to rotate the driving wheel 1; a torque detecting device 3 to detect the loading torque to the driving wheel; a motor control circuit 4 to carry out the ON and OFF control and the like of an electric motor 2; a lead secondary battery 5 to feed the power source to the electric motor 2; a load-carrying platform 6 to load baggages; and a traction member 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a carrier used by a person for carrying luggage or the like by pushing or pulling it.

[0002]

2. Description of the Related Art FIG. 5 is an external view showing an outline of a conventional tow truck, including wheels 50, a frame 51, and a luggage storage section 5.
2. It is composed of a towing handle 53 and the like. Such conventional tow trucks or human-powered wheelbarrows can easily carry luggage with a small amount of force when moving on a flat road, etc., but when climbing a sloping slope, a step on a flat ground It is necessary to apply a large force in a short time in order to grasp the towing handle 53 and move it when passing, when pushing a heavy object in the luggage storage unit 52 or when starting towing, etc. In other words, the torque opposite to the direction desired to be moved in a short time is applied to the wheel 50.

[0003]

However, in such a situation, there is a problem that when a powerless person such as an old man or a woman tries to operate this, he or she may not move or may be in a dangerous state.

Therefore, in order to move the wheelbarrow or towing vehicle when climbing a sloped slope, passing through a step on a level ground, or when starting to push or pull a heavy object, It is desirable to supplement the force required for driving, such as towing, in situations where a large amount of force is required in a short time.

In consideration of the above-mentioned problems of conventional vehicles, the present invention provides a power assist function capable of preventing an inadequate person such as an old man or a woman from moving or in a dangerous state when trying to operate it. The purpose of the present invention is to provide an attached carrier.

[0006]

SUMMARY OF THE INVENTION The present invention provides a handle for pushing or pulling by hand, a drive wheel, a motor for driving the drive wheel, and a storage means for supplying electric power to the motor. , A torque detecting means for detecting a load torque applied to the drive wheel when the handle is pushed or pulled, and a motor for turning on the motor when the torque detected by the torque detecting means is equal to or more than a predetermined value. -A vehicle with a power assist function including a power control means, for example, using a chargeable / dischargeable battery and / or a large-capacity capacitor as a power storage means, and determining whether the load torque on the drive wheels is equal to or more than a predetermined value. Is detected by the torque detecting means, and when it is less than a predetermined value, the motor is not energized, and when it is more than the predetermined value, electric energy is supplied to the motor and the drive wheels are auxiliary driven by electric power.

As described above, by backing up the power load on the transport vehicle, which is equal to or more than a predetermined value, with the battery and / or the large-capacity capacitor, a person who is weak can easily operate even with a large fluctuating load.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings showing an embodiment. (Embodiment 1) FIG. 1 is a block diagram showing an example of the configuration of a tow truck which is a carrier with a power assist function according to a first embodiment of the present invention. That is, the towing cart includes a drive wheel 1 which is a wheel, an electric motor 2 for rotating the drive wheel 1, a torque detection device 3 as a torque detection means for detecting a load torque on the drive wheel 1, and an electric motor 2. A motor control circuit 4 serving as a motor control means for performing on / off control, a lead secondary battery 5 serving as a power storage means for supplying power to the electric motor 2, and a luggage carrier 6 for loading luggage. , A towing portion 7 as a handle portion for grasping and pulling with a hand, a brake 8 for stopping the drive wheel 1, and the like.

The load torque applied to the drive wheel 1 is detected by, for example, detecting the torsional stress of the rotating shaft of the electric motor 2 using a strain gauge or the like. That is, when trying to tow a tow cart with the tow section 7,
The rotating shaft tries to rotate in the pulled direction, but the driving wheel 1 generates a torque that resists the rotating direction, and the rotating shaft is twisted according to the pulling force at that time. Therefore, the load torque on the drive wheel 1 can be detected by detecting the twist generated in this shaft.

Alternatively, a change in the flexing condition of the shaft when a slope is applied from a flat ground may be detected by attaching a strain gauge or the like in the axial direction of the shaft. Alternatively, a gauge may be attached to the bearing to detect a change in the shape of the bearing.

Next, the operation of the towing cart according to the first embodiment will be described with reference to the drawings.

First, when the above-mentioned tow cart is towed on a flat sidewalk or the like, the towing force may be small and the load torque on the drive wheel 1 is small, so that the torque detected by the torque detection device 3 is beforehand determined. It is smaller than a predetermined value, that is, a specified value. Based on the detection result of the torque detection device 3, the motor control circuit 4 operates from the lead secondary battery 5 to the electric motor.
It is towed in the same way as a conventional tow truck without supplying electric energy to the turret 2. In addition, when the tow cart accelerates due to gravity, such as a steep downhill slope, the brake 8 can be appropriately operated for easy towing.

Next, when the towing cart is towed by a step or an uphill, a large traction force must be applied to move the towing cart. At this time, the torque detection device 3 detects the load torque applied to the drive wheels 1, and when the detected torque is equal to or greater than a specified value, the motor control circuit 4 transfers the lead secondary battery 5 to the electric motor 2. Electric energy is supplied and the drive wheels 1 are driven by electric power. By assisting the driving force in this way, even a weak person can easily move the tow cart. (Embodiment 2) FIG. 2 is a block diagram showing a configuration of a towing cart which is a carrier with a power assist function according to a second embodiment of the present invention. That is, the tow cart is
A drive wheel 11 that is a wheel, an electric motor 12 that rotates the drive wheel 11, a torque detection device 13 that detects a load torque on the drive wheel 11, a motor control circuit that performs on / off control of the electric motor 12, and the like. 14, Ni as a storage means
The Cd secondary battery 15 and the electric double layer capacitor 16, the platform 17, the towing unit 18, the brake 19 and the like are included. However, the Ni-Cd secondary battery 1 used in the present embodiment
The weight of 5 is 1 / the weight of the lead secondary battery 5 of the first embodiment.
4.

Next, the operation of the tow cart of the second embodiment will be described with reference to the drawings.

As in the case of the first embodiment, the torque detection device 13 detects whether or not the load torque applied to the drive wheels 11 when a person holds the tow portion 18 and pulls the load torque. When the torque is below the specified value, the electric motor 12 is not energized. When the torque is above the specified value, the electric motor 12 is supplied with Ni-C.
d Electric energy is supplied from the secondary battery 15 and the electric double layer capacitor 16 to drive the drive wheels 11 with electric power.
However, when the load torque exceeds the specified value and is small, the Ni-Cd secondary battery 15 mainly supplies electric energy to the electric motor 12, and when the load torque is large, the electric double layer capacitor 16 is mainly used. Electric energy from electric motor 1
Feed to 2. The ratio of electric energy supplied from the Ni-Cd secondary battery 15 and the electric double layer capacitor 16 is determined by the motor control circuit 14. (Embodiment 3) FIG. 3 is a block diagram showing the configuration of a tow truck which is a carrier with a power assist function according to a third embodiment of the present invention. That is, the tow cart is
A drive wheel 21, which is a wheel, an electric motor 22 that rotates the drive wheel 21, a torque detection device 23 that detects a load torque on the drive wheel 21, a motor control circuit that performs on / off control of the electric motor 22, and the like. 24, an electric double layer capacitor 25 as a power storage unit, a luggage carrier 26, a towing unit 27, a brake 28, and a generator 29 that generates power when a reverse load torque is applied.

FIG. 4 is a general external view of a towing cart which is a carrier of the present invention.
It comprises a frame 31, a luggage storage unit 32 as a luggage carrier, a towing handle 33, a power supply unit 34 having a power storage means, an electric control unit 35 for controlling a motor 36, and a motor 36.

Next, the operation of the towing cart of the third embodiment will be described with reference to the drawings.

Similar to the case of the first or second embodiment, the torque detection device determines whether or not the load torque applied to the drive wheels 21 when a person holds the tow portion 27 and pulls the load torque. 23, the electric motor 22 is not energized when the torque is below the specified value, and the electric motor 2 is supplied when the torque is above the specified value.
Electric energy is supplied to the electric double layer capacitor 25 from the electric double layer capacitor 25 to drive the drive wheels 21 with electric power.

When the tow vehicle is towed downhill, gravity causes a reverse rotation load on the electric motor 22. In the present embodiment, this energy can be used to generate DC electric energy by the generator 29, and the energy obtained by the power generation is charged into the electric double layer capacitor 25. The energy regenerated in this way can be used again for the next power assist.

The characteristics of the towing cart obtained in the above embodiment are shown in Table 1 in comparison with the comparative example. The comparative example in (Table 1) shows the characteristics of an ordinary towing vehicle that does not have an electric power assist mechanism.

Here, the results of (Table 1) are based on data obtained when going up and down the same distance on a slope having an inclination of 5 degrees.

[0022]

[Table 1]

As described above, according to the present invention, by detecting the load torque applied to the wheel and electrically assisting the driving of the wheel with a secondary battery or an electric double layer capacitor, etc., if necessary, the elderly or Even weak people such as women can easily carry luggage. It is also possible to carry heavy objects with a small force.

In the above embodiment, the lead secondary battery, the combination of the Ni-Cd secondary battery and the electric double layer capacitor, or the electric double layer capacitor is used as the power storage means, but the present invention is not limited to this. In the embodiment of
For example, a lead secondary battery, a Ni-Cd secondary battery, an electric double layer capacitor may be used alone, or a part or all of them may be used in combination. Alternatively, a primary battery may be used.

In each of the above-mentioned second and third embodiments, the electric double layer capacitor is used as the large capacity capacitor, but if there is a capacity capable of driving the motor for a required time, other These types of capacitors may be used.

In the third embodiment, a generator is provided separately, but instead of this, a motor capable of generating power is used to generate power when the motor rotates in the reverse direction. It may be configured to regenerate electric energy. That is, the mode
The generator and the generator may be combined.

Further, in each of the above-described embodiments, the traction type carrier vehicle is described as an example, but the present invention is not limited to this, and may be applied to a hand-push type carrier vehicle (hand cart).

In each of the above-described embodiments, the torque detection device and the motor control circuit are configured by dedicated hardware, but instead of this, the same function is realized by software using a computer. You may.

[0029]

As is apparent from the above description, the present invention is directed to a motor for driving a drive wheel, a storage means for supplying electric power to the motor, and a handle portion for manually pushing or pulling. Since the torque detection means for detecting the load torque on the drive wheels and the motor control means for turning on the motor when the torque detected by the torque detection means is equal to or more than a predetermined value are provided. , It has the merit that when a weak person such as an old man or a woman tries to operate it, he / she can not move or become in a dangerous state.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a carrier with a power assist function according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a carrier with a power assist function according to a second embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of a carrier with a power assist function according to a third embodiment of the present invention.

FIG. 4 is an external view of the tow cart of the above embodiment.

FIG. 5 is an external view of a conventional carrier.

[Explanation of symbols]

 1, 11, 21 Drive wheels 2, 12, 22 Electric motor 3, 13, 23 Torque detection device 4, 14, 24 Motor control circuit 5 Lead secondary battery 7, 18, 27 Traction unit 15 Ni- Cd secondary battery 16,25 Electric double layer capacitor

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tetsuo Tetsuo, Osaka Prefecture Kadoma City 1006 Kadoma, Matsushita Electric Industrial Co., Ltd. (72) Inventor Masaki Ikeda 1006 Kadoma, Kadoma-shi, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (4)

[Claims] 1. A handle portion for pushing or pulling by hand,
A drive wheel, a motor for driving the drive wheel, a power storage means for supplying electric power to the motor, and a torque detection for detecting a load torque on the drive wheel when the handle is manually pushed or pulled. And a motor control means for turning on the motor when the torque detected by the torque detection means is equal to or more than a predetermined value. 2. The transport vehicle with a power assist function according to claim 1, wherein the power storage means has a chargeable / dischargeable secondary battery and / or a large-capacity capacitor. 3. A generator connected to drive wheels, wherein when reverse torque is applied to the motor, electric power generated by the generator is stored in the storage means to regenerate energy. The carrier with a power assist function according to claim 2. 4. The vehicle with a power assist function according to claim 2, wherein the large-capacity capacitor is an electric double layer capacitor composed of an activated carbon polarizable electrode and an electrolytic solution.