JP4124979B2 - Hydraulically driven generator - Google Patents

Description

BACKGROUND OF THE INVENTION
[0001]
The present invention relates to a generator that generates power by engine output, and more particularly to a hydraulically driven generator that facilitates the arrangement of the generator, eliminates hydraulic hunting, and simplifies a cooler structure.
[Prior art]
[0002]
Conventionally, the generator is often driven by the output of the engine. In particular, when operating an on-vehicle power device, it is difficult to obtain external power, and therefore power generation by engine output is effective. Therefore, conventionally, a pulley is attached to the output rotation shaft of the engine, one side of the belt is hung on the pulley, and the opposite side of the belt is hung on the rotation shaft of the generator. Therefore, the generator is usually installed around the engine with their axes parallel to each other.
[Problems to be solved by the invention]
[0003]
By the way, in the prior art, since the engine and the generator are mechanically connected by a power transmission mechanism, the arrangement relationship between the engine and the generator is limited. In consideration of transmission efficiency, it is desirable to place a generator near the engine. On the other hand, a generator is placed near the engine from the viewpoint of compacting the vehicle or improving the weight balance. Sometimes you don't want to place it. Because of these conflicting requirements, generator placement is a challenge for designers.
[0004]
Further, the applicant of the present invention proposes a hydraulically driven generator using hydraulic pressure in the present invention, but when this hydraulically driven generator was actually prototyped, hydraulic hunting was proposed. It is foreseen that there are problems such as these and the advantage that the structure of the cooler can be simplified. The hydraulic hunting seems to be caused by resonance with the hydraulic control when the output control of the generator is performed.
[0005]
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a hydraulically driven generator that solves the above-described problems, facilitates the arrangement of the generator, has no hydraulic hunting, and simplifies the cooler structure.
[Means for Solving the Problems]
[0006]
In order to achieve the above object, according to the first aspect of the present invention, an input rotary shaft of an oil pump is connected to an output rotary shaft of an engine, and an oil motor that is rotated by the output hydraulic pressure of the oil pump is provided. In a hydraulically driven generator in which a rotating shaft of a generator is connected to an output rotating shaft, the generator has a cooling oil supply port, and an output hydraulic pipe of the oil pump is branched to supply an oil supply port of the oil motor and The oil connected to the cooling oil supply port of the generator is configured to use oil supplied from the oil pump for cooling the generator .
[0007]
According to a second aspect of the present invention, in the first aspect of the present invention, a flywheel is provided between the output rotation shaft of the oil motor and the rotation shaft of the generator .
[0008]
According to a third aspect of the present invention, in the first aspect of the present invention, a speed increasing mechanism is provided between the output rotation shaft of the oil motor and the rotation shaft of the generator .
[0010]
Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.
[0011]
As shown in FIG. 1, a hydraulically driven generator according to the present invention has an input rotary shaft of an oil pump 2 connected to an output rotary shaft of an engine 1, and is rotationally driven by the output hydraulic pressure of the oil pump 2. An oil motor 3 is provided. Furthermore, the rotating shaft of the generator 4 is connected to the output rotating shaft of the oil motor 3. The generator 4 is, for example, a permanent magnet generator in which a rotor is configured with a permanent magnet and a stator is configured with a coil. The output of the generator 4 is connected to a load (not shown) via the power control unit 5. A flywheel 6 is provided between the output rotation shaft of the oil motor 3 and the rotation shaft of the generator. The output hydraulic pipe 11 of the oil pump 2 is branched and connected to the oil supply port 12 of the oil motor 3 and also connected to the cooling oil supply port 13 of the generator 4. An oil drain pipe 16 to an oil tank (not shown) is connected to the oil drain port 14 of the oil motor 3 and the cooling oil drain port 15 of the generator.
[0012]
According to the present invention, the output of the engine 1 is once converted into hydraulic pressure by the oil pump 2 and transmitted to the oil motor 3, and is converted again into rotational force by the oil motor 3. Then, the rotor of the generator 4 is rotated by the rotational force of the oil motor 3. Thereby, the output of the engine 1 can be taken out from the power control unit 5 as electric power.
[0013]
According to the present invention, the engine 1 and the generator 4 are not mechanically connected by the power transmission mechanism, and the generator 4 can be disposed separately from the engine 1. Since the oil pump 2 and the oil motor 3 are significantly smaller than the generator 4, there is no restriction on arrangement. Therefore, the engine 1 and the generator 4 may be arranged at desired locations. The hydraulic pipe 11 connecting the oil pump 2 and the oil motor 3 can be routed arbitrarily, and does not restrict the arrangement.
[0014]
The above effect can also be obtained by directly connecting the output rotation shaft of the oil motor 3 and the rotation shaft of the generator 4, but hydraulic hunting may occur with the output control of the generator when actually manufactured. there were. However, according to the present invention, since the flywheel 6 is provided between the output rotation shaft of the oil motor 3 and the rotation shaft of the generator 4, the resonance relationship between the output control of the generator 4 and the hydraulic control is established. Even if there is a sign of hydraulic hunting in the hydraulic system that is blocked by the flywheel 6, the rotation of the generator 4 is not affected by the hydraulic hunting because the flywheel 6 stabilizes the rotation. Thereby, a stable power generation output can be obtained.
[0015]
Further, according to the present invention, part of the oil supplied from the oil pump 2 is used for cooling the generator 4. Since the generator 4 is oil-cooled, the cooling efficiency is better than the conventional air cooling, and the cooling structure of the generator 4 can be downsized.
[0016]
Next, another embodiment of the present invention is shown in FIG. This hydraulically driven generator is provided with a speed increasing mechanism 7 between the output rotating shaft of the oil motor 3 and the rotating shaft of the generator 4. The other parts are the same as in FIG. In the speed increasing mechanism 7, an input shaft having a gear 8 having a large number of teeth is connected to an output rotating shaft of the oil motor, and an output shaft having a gear 9 having a small number of teeth is connected to a rotating shaft of a generator.
[0017]
Even in this configuration, the generator 4 can be arranged separately from the engine 1. Moreover, since the number of rotations is increased by the speed increasing mechanism 7, it is possible to extract larger electric power from the same generator 4 as compared with the case where the speed is not increased. Further, in this configuration, the effect of preventing hydraulic hunting was experimentally confirmed, as in the configuration of FIG. 1 provided with the flywheel 6. The reason could not be clarified, but it is also considered that the speed increasing mechanism 7 has a large inertia like the flywheel 6.
[0018]
Next, the structure of the generator will be described.
[0019]
The generator shown in FIG. 3 is an integrated generator body and speed increasing mechanism. A speed increasing mechanism housing 31 forming an outer shell of the speed increasing mechanism is fixed to one end of a generator main body housing 32 forming an outer shell of the generator main body. An input bearing 33 is provided at the input side end of the speed increasing mechanism housing 31 and the end opposite thereto, and an input shaft 34 inserted into the speed increasing mechanism housing 31 is supported by the input bearing 33. A large-diameter input side gear 35 is attached to the input shaft 34 in the speed increasing mechanism housing 31. At the output side end of the speed increasing mechanism housing 31, the rotating shaft 36 of the generator is inserted into the speed increasing mechanism housing 31 and is arranged in parallel with the input shaft 34. An output side gear 37 that is meshed with the input side gear 35 and that has a smaller diameter than the input side gear 35 and therefore has a smaller number of teeth is attached to the rotary shaft 36.
[0020]
A rotor 38 made of a permanent magnet is attached to the rotating shaft 36 of the generator. The rotor 38 has a plurality of permanent magnets arranged in the circumferential direction so that the polarities of the magnetic poles appearing on the outer peripheral surface are alternately reversed. The periphery of the rotor 38 is surrounded by a stator 39. On the stator 39, a plurality of stator teeth (not shown) are arranged side by side in the circumferential direction with their end faces facing radially inward. Each stator tooth is wound. The detailed structure of the rotor and the stator and the electrical connection of the windings can be sufficiently implemented by a known generator technology, and thus the description thereof is omitted.
[0021]
Bearings 41 are provided at both ends of the generator body housing 32, and a rotating shaft 36 is supported by the bearings 41. The stator 39 is fixed to the generator body housing 32 that surrounds the stator 39.
[0022]
A spiral groove 42 surrounding the outer periphery of the stator 39 is formed on the inner periphery of the generator body housing 32. A communication flow path 43 that connects the generator main body housing 32 and the speed increasing mechanism housing 31 is formed at a connection portion between the generator main body housing 32 and the speed increasing mechanism housing 31. A cooling oil drain port 44 is formed in the lower portion of the speed increasing mechanism housing 31. A cooling oil supply port 45 is formed in the upper part of the generator body housing 32. That is, in this configuration, the oil is also turned to the speed increasing mechanism. The branch of the output hydraulic pipe 11 of the oil pump 2 shown in FIG. 2 is connected to the cooling oil supply port 45 in the upper part of the generator body housing 32 here. The oil supplied from the oil pump 2 first enters the generator main body housing 32, travels around the outer periphery of the stator 39 through the spiral groove 42, and enters the speed increasing mechanism housing 31 through the communication channel 43. The oil is discharged from the cooling oil discharge port 44 to the oil discharge pipe 16. That is, the oil that has cooled the generator passes through the communication channel 43 and is also used to lubricate the speed increasing gear, and is then discharged.
[0023]
Next, an embodiment of a vehicle equipped with a hydraulically driven generator will be described.
[0024]
The vehicle shown in FIG. 4 is a heavy machine equipped with a lifting magnet. This heavy machine includes a main arm 52 that is raised and lowered by a hydraulic cylinder 51, a sub arm 54 that is swung back and forth by a hydraulic cylinder 53 with the tip of the main arm 52 as a fulcrum, and a hydraulic cylinder that is provided at the tip of the sub arm 54. The lifting magnet 56 is tilted back and forth at 55, the driver's seat 57 that is turned together with the main arm 52, and the endless track wheel 58 that supports the driver's seat 57 and moves back and forth and turns. An instrument panel, a control panel, a switchboard (boards not shown), the engine 1 and the generator 4 are mounted on the driver seat 57. An oil pump 2 is attached to the engine 1. The oil pump 2 is separate from the hydraulic system of the hydraulic cylinder and is provided exclusively for the hydraulically driven generator. The generator 4 is a hydraulically driven generator in which a speed increasing mechanism is integrated, and the oil motor 3 is attached to the generator 4.
[0025]
This heavy machine handles materials that can be held by magnetic force such as iron scraps and iron materials. The lifting magnet 56 is an electromagnet, and loads are attracted and released by controlling the current of the magnet coil. When releasing, it is necessary to pass a magnet current having a polarity opposite to that at the time of adsorption. The current of the magnet coil is supplied from the generator 4. The power control unit 5 is provided with a constant voltage circuit that adjusts the output voltage by switching, and a polarity switching circuit that reverses the polarity of the output voltage and supplies it to the magnet coil.
[0026]
According to the present invention, the generator 4 can be arranged separately from the engine 1. In the case of FIG. 4, the engine 1 is arranged in the engine room at the rear of the driver seat 57 with the axis left and right, whereas the generator 4 is arranged in the upper part of the driver seat 57 with the axis back and forth. Yes.
【The invention's effect】
[0027]
The present invention exhibits the following excellent effects.
[0028]
(1) Since the generator can be installed at any place with respect to the engine, the layout design becomes easy.
[0029]
(2) Since the flywheel stabilizes rotation, hydraulic hunting can be eliminated.
[0030]
(3) Since the generator is oil-cooled, the cooling efficiency is good and the generator cooling structure can be downsized.
[0031]
(4) The speed increasing mechanism can increase the rotational speed and take out a large amount of electric power.
[Brief description of the drawings]
[0032]
FIG. 1 is a configuration diagram of a hydraulically driven generator showing an embodiment of the present invention.
FIG. 2 is a configuration diagram of a hydraulically driven generator showing an embodiment of the present invention.
FIG. 3 is a cross-sectional view of a speed increasing mechanism-integrated hydraulically driven generator showing an embodiment of the present invention.
FIG. 4 is a configuration diagram of a heavy machine equipped with a hydraulically driven generator according to the present invention.
[Explanation of symbols]
[0033]
1 engine 2 oil pump 3 oil motor 4 generator 6 flywheel 7 speed increasing mechanism

Claims (3)

An oil drive is connected to the output rotation shaft of the engine, and an oil motor is provided that is driven to rotate by the output hydraulic pressure of the oil pump. The oil drive is connected to the output rotation shaft of the oil motor. Type generator,
The generator has a cooling oil filler opening;
The output hydraulic piping of the oil pump is branched and connected to an oil supply port of the oil motor and a cooling oil supply port of the generator,
Hydraulic driven generator, characterized by being configured the oil supplied from the oil pump as used in the cooling of the generator. Hydraulic driven generator according to claim 1, characterized in that a flywheel between the rotation axis of the output rotary shaft and the generator of the oil motor. The hydraulic drive generator according to claim 1, wherein a speed increasing mechanism is provided between an output rotation shaft of the oil motor and a rotation shaft of the generator.

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