JP7555301B2 - Oil supply device for rotating electric machine and rotating electric machine system - Google Patents

Description

The present invention relates to an oil supply device for a rotating electric machine and a rotating electric machine system.

Conventionally, a rotating electric machine system is known that includes a rotating electric machine having a shaft, a bearing that supports the shaft, and an oil tank that contains the bearing and oil, and an oil supply device for the rotating electric machine that supplies oil to the oil tank. One oil supply device for the rotating electric machine of this type includes an electric pump that supplies oil to the oil tank during normal operation of the rotating electric machine, and an oil supply unit for power outages that supplies oil to the oil tank when the electric pump becomes inoperable due to a power outage.

JP 2019-201439 A

The oil supply unit for power outages has a tank for storing oil and piping that connects the tank to the oil tank of the rotating electric machine, and in the event of a power outage, the oil in the tank flows by gravity through the piping into the oil tank. The oil supply unit for power outages is required to supply an amount of oil to the oil tank (bearings) according to the rotation speed of the shaft until the shaft stops rotating after the power supply to the rotating electric machine is cut off due to a power outage or the like. However, because conventional tanks only have one port for supplying oil to the oil tank, it was difficult to ensure the necessary amount of oil to be supplied to the oil tank and the necessary supply time.

Therefore, one of the objectives of the present invention is to provide an oil supply device for a rotating electric machine and a rotating electric machine system that can easily ensure the amount and supply time of oil supplied from a tank to an oil supply target during a power outage.

An oil supplying device for a rotating electric machine according to an embodiment of the present invention is an oil supplying device for a rotating electric machine that supplies oil to an oil supply target of a rotating electric machine, and includes a pump that discharges the oil, a tank located above the oil supply target, storing the oil, and having a plurality of ports at different vertical positions, a main oil supply pipe that connects the pump and the oil supply target and through which the oil flows, a branch oil supply pipe that branches off from the main oil supply pipe, connects the main oil supply pipe to the plurality of ports, and through which the oil flows, a check valve that is provided in the main oil supply pipe between the pump and the branch oil supply pipe, allowing the oil to flow from the pump toward the oil supply target and the tank, and restricting the oil from the oil supply target and the tank toward the pump, and a valve that connects the branch oil supply pipe to the oil supply target. and a guide section that connects the multiple ports to the oil supply target and guides the oil flowing out from the multiple ports by gravity to the oil supply target, wherein the tank has a wall extending in the vertical direction, and the multiple ports are provided in the wall so as to be shifted in a width direction of the wall perpendicular to the vertical direction, and the guide section has a plurality of pipes that are included in the branch oil supply pipe and connected to the multiple ports, and a plurality of orifices provided in each of the plurality of pipes, and the multiple orifices are located below the tank, and are provided in the multiple pipes that are lined up in the width direction and lined up in the width direction when viewed from a thickness direction of the wall perpendicular to the vertical direction and the width direction .

The oil supply device for a rotating electrical machine of the present invention makes it possible to obtain an oil supply device for a rotating electrical machine and a rotating electrical machine system that can easily ensure the amount and time of oil supply from the tank to the oil supply target during a power outage.

FIG. 1 is a diagram illustrating an example of the configuration of a rotating electrical machine system according to an embodiment, in a normal operating state. FIG. 2 is a cross-sectional view illustrating an example of a rotating electric machine of the rotating electric machine system according to the embodiment. FIG. 3 is an exemplary cross-sectional view showing two orifice plates of an oil supply device in a rotating electrical machine system according to an embodiment. FIG. 4 is a diagram showing an example of the configuration of the rotating electrical machine system according to the embodiment, in a state during a power outage. FIG. 5 is a diagram showing the relationship between the amount of oil (oil amount) supplied by the oil supplying device and time in the rotating electrical machine system of the embodiment. FIG. 6 is a diagram showing the relationship between the amount of oil (oil amount) supplied by the oil supplying device and time in the rotating electrical machine system of the comparative example.

The following describes exemplary embodiments of the present invention. The configurations (technical features) of the embodiments described below, as well as the actions and results (effects) brought about by the configurations, are merely examples.

Please note that the drawings are schematic, and the dimensional relationships and ratios of each element may differ from reality. Furthermore, there may be parts in which the dimensional relationships and ratios differ between the drawings.

<Rotating Electric Machine System 1>
Fig. 1 is a diagram illustrating an example of a configuration of a rotating electric machine system 1 according to an embodiment, in a normal operating state. As illustrated in Fig. 1, the rotating electric machine system 1 includes a rotating electric machine 2 and an oil supplying device 3 that supplies oil 100 to the rotating electric machine 2. The oil supplying device 3 is an example of an oil supplying device for a rotating electric machine.

<Rotating Electric Machine 2>
2 is a cross-sectional view illustrating an example of the rotating electric machine 2 of the rotating electric machine system 1 according to the embodiment. As illustrated in FIG. 2, the rotating electric machine 2 includes a housing 11, a rotor 12, a stator 13, a bearing 16, and an oil tank 17.

The housing 11 is formed in a box shape. The housing 11 houses a part of the rotor 12 and the stator 13.

The rotor 12 has a shaft 14 and a rotor core 15. The rotor core 15 is fixed to the portion of the shaft 14 between both axial ends.

The shaft 14 is supported by the housing 11 via two bearings 16 so as to be rotatable around the central axis of rotation Ax. In other words, the two bearings 16 support the shaft 14 so as to be rotatable relative to the housing 11. The two bearings 16 are located on both sides of the rotor core 15 in the axial direction. In other words, the rotor core 15 is located between the two bearings 16 in the axial direction.

Both axial ends 14a, 14b of the shaft 14 protrude from the housing 11 to the outside of the housing 11. One end 14a is coupled to a coupling object (not shown). In addition, an inner fan 18 is fixed between each of the two bearings 16 and the rotor core 15 on the shaft 14. The inner fan 18 rotates integrally with the shaft 14.

The two bearings 16 are supported by the housing 21. The bearings 16 are, for example, sliding bearings or rolling bearings. The bearings 16 are lubricated by oil 100. The bearings 16 are disposed in an oil tank 17 provided in the housing 21. Oil 100 (see FIG. 1) is placed in the oil tank 17. The oil tank 17 is also referred to as a sealed portion. The oil tank 17 is an example of an oil supply target.

The stator 13 has a stator core 19 and a stator winding 20. The stator core 19 is fixed to the housing 11. That is, the stator 13 is fixed to the housing 11. The stator core 19 is located radially outside the rotor core 15 and is formed in a cylindrical shape surrounding the rotor core 15. The stator winding 20 is fixed to the stator core 19 by passing through multiple slots (not shown) formed in the inner periphery 19a of the stator core 19 so as to extend in the axial direction.

<Oil supply device 3>
As shown in FIG. 1 , the oil supply device 3 includes an electric pump 51 , a tank 52 , a check valve 53 , and a piping section 54 .

The electric pump 51 draws in the oil 100 stored in the main tank (not shown) and discharges the oil 100 into the piping section 54. The electric pump 51 is powered by electricity.

The tank 52 stores a portion of the oil 100 discharged from the electric pump 51. The tank 52 is formed, for example, in a rectangular shape and has a bottom wall 52a, a top wall 52b, and four side walls 52c. Note that only three of the four side walls 52c are shown in FIG. 1. The side walls 52c extend in the vertical direction and connect the bottom wall 52a and the top wall 52b. The side walls 52c are an example of a wall. The tank 52 is also called a rundown tank.

The tank 52 is provided with two inlets 52d, 52e and one outlet 52f. The two inlets 52d, 52e are provided on one side wall 52c. The two inlets 52d, 52e are located above the oil tank 17 (bearing 16). The two inlets 52d, 52e are located at different positions in the up-down direction. The inlet 52e is located above the inlet 52d. As an example, the outlet 52f is provided on a side wall 52c other than the side wall 52c on which the inlets 52d, 52e are provided. The outlet 52f is located above the two inlets 52d, 52e. The two inlets 52d, 52e are an example of multiple ports.

The piping section 54 has a main oil supply pipe 61, a branch oil supply pipe 62, an oil drain pipe 63, and an overflow pipe 64. Oil 100 flows through the piping section 54.

The main oil supply pipe 61 connects the electric pump 51 to the inlet of the oil tank 17 (Figure 2) of the rotating electric machine 2. The main oil supply pipe 61 is provided with a check valve 53.

The branched fuel supply pipe 62 branches off from the main fuel supply pipe 61 at a portion between the check valve 53 and the oil tank 17 to the tank 52. That is, the branched fuel supply pipe 62 connects the main fuel supply pipe 61 and the tank 52. The branched fuel supply pipe 62 has a first portion 62a, a second portion 62b, a third portion 63c, and a branch point 63d. The first portion 62a connects the main fuel supply pipe 61 and the branch point 63d. The second portion 62b connects the branch point 63d and the inlet/outlet 52d of the tank 52. The third portion 63c connects the branch point 63d and the inlet/outlet 52e of the tank 52. That is, the second portion 62b and the third portion 62c have different mounting heights. The second portion 62b and the third portion 62c are an example of multiple pipes.

The branch oil supply pipe 62 and the portion of the main oil supply pipe 61 between the portion connected to the branch oil supply pipe 62 and the portion connected to the oil tank 17 (hereinafter also referred to as the downstream portion) 61a constitute the guide section 67. The guide section 67 connects the inlets 52d, 52e to the oil tank 17, and guides the oil 100 that flows out of the inlets 52d, 52e by gravity to the oil tank 17. The guide section 67 and the tank 52 constitute an oil supply section for power outages.

The second part 62b and the third part 62c are provided with orifice plates 65, 66, respectively.

Figure 3 is an exemplary cross-sectional view showing two orifice plates 65, 66 of the oil supply device 3 in the rotating electric machine system 1 of the embodiment. As shown in Figure 3, the two orifice plates 65, 66 are provided with orifices 65a, 66a, respectively. The orifices 65a, 66a correspond to the inlets 52d, 52e, respectively. The diameter of the orifice 66a is larger than the diameter of the orifice 65a. That is, the higher the vertical position of the inlets 52d, 52e corresponding to the orifices 65a, 66a, the larger the diameter of the orifices 65a, 66a. Note that the diameters of the orifices 65a, 66a may be the same, or may be smaller the higher the vertical position of the inlets 52d, 52e corresponding to the orifices 65a, 66a. The orifices 65a, 66a are included in the guide section 67.

The check valve 53 provided in the main oil supply pipe 61 shown in FIG. 1 allows oil 100 to flow from the electric pump 51 toward the oil tank 17 and the tank 52, and restricts oil 100 from flowing from the oil tank 17 and the tank 52 toward the electric pump 51.

The oil drain pipe 63 connects the outlet of the oil tank 17 to the main tank. The overflow pipe 64 connects the outlet 52g of the tank 52 to the oil drain pipe 63.

<Flow of 100 oil>
Next, the flow of the oil 100 will be described. First, the flow of the oil 100 during normal operation of the rotating electric machine system 1 will be described with reference to FIG. 1. The arrows in FIG. 1 show an example of the flow of the oil 100 during normal operation of the rotating electric machine system 1. When the rotating electric machine 2 and the electric pump 51 are energized and start operating, the shaft 14 rotates and the electric pump 51 draws and discharges the oil 100 from the main tank. A part of the oil 100 discharged from the electric pump 51 is supplied to the oil tank 17 via the main oil supply pipe 61 to lubricate the bearings 16. The oil 100 that has lubricated the bearings 16 returns to the main tank from the oil tank 17 via the oil drain pipe 63. A part of the oil discharged from the electric pump 51 flows from the main oil supply pipe 61 into the branch oil supply pipe 62. The oil 100 that flows into the branch oil supply pipe 62 passes through the second portion 62b and the third portion 62c to reach the inlets 52d and 52e of the tank 52, and flows into the tank 52 from the inlets 52d and 52e. This causes the oil to be stored in the tank 52. When the amount of oil 100 stored in the tank 52 reaches a predetermined amount, the oil 100 flows out from the outlet 52f into the overflow pipe 64. The oil 100 that flows out into the overflow pipe 64 returns to the main tank via the overflow pipe 64 and the oil drain pipe 63.

Next, the flow of oil 100 during a power outage in the rotating electric machine system 1 in which the electric pump 51 is inoperable due to a power outage or the like will be described with reference to FIG. 4. FIG. 4 is a configuration diagram illustrating an example of the configuration of the rotating electric machine system 1 of the embodiment, and is a diagram illustrating a state during a power outage. The arrows in FIG. 4 indicate an example of the flow of oil 100 during a power outage in the rotating electric machine system 1. During a power outage, the rotating electric machine 2 and the electric pump 51 stop. At this time, the rotation speed of the shaft 14 gradually decreases, and finally the shaft 14 stops. In addition, the oil 100 flows as follows under the influence of gravity. The oil 100 in the tank 52 flows out from the inlets 52d and 52e to the second part 62b and the third part 62c of the branch oil supply pipe 62, respectively, and is supplied to the oil tank 17 via the first part 62a and the downstream part 61a of the main oil supply pipe 61 to lubricate the bearings 16. The oil 100 that has lubricated the bearings 16 returns to the main tank from the oil tank 17 via the oil drain pipe 63. As a result, even if the electric pump 51 stops during a power outage, the oil 100 in the tank 52 is supplied to the oil tank 17 and thus to the bearings 16 at least until the shaft 14 stops. Therefore, the oil 100 can sufficiently lubricate the bearings 16. Specifically, in this embodiment, the amount and supply time of oil required for the rotation (so-called free run) of the shaft 14 from the rated number of revolutions of the shaft 14 (rotor 12) until the shaft 14 (rotor 12) stops can be secured. Here, the higher the rotation speed of the shaft 14, the greater the amount of oil (amount per unit time) required to lubricate the bearings 16. The amount of oil required to lubricate the bearings 16 is the amount of oil to be supplied to the oil tank 17. In other words, the amount of oil to be supplied to the oil tank 17 increases as the rotation speed of the shaft 14 increases. Hereinafter, the amount of oil required to lubricate the bearings 16, i.e., the amount of oil to be supplied to the oil tank 17, will also be referred to as the required amount.

Figure 5 is a diagram showing the relationship between the amount of oil (oil volume) supplied by the oil supplying device 3 in the rotating electric machine system 1 of the embodiment and time. The vertical axis of Figure 5 indicates the amount of oil (oil volume) supplied by the oil supplying device 3 during a power outage, and the horizontal axis of Figure 5 indicates the elapsed time from the time of the power outage (time in Figure 5). Line L1 indicates the actual amount of oil (oil volume) supplied by the oil supplying device 3. Line L2 indicates the required amount (design value), which is the amount of oil (oil volume) that the oil supplying device 3 should supply. From the time of the power outage to time t2, the oil 100 in the tank 52 flows out from both of the two inlets 52d and 52e and is supplied to the oil tank 17. At this time, from time t1 to time t2, the oil level 100a (upper surface) of the oil 100 in the tank 52 is located between the upper end and the lower end of the inlet 52e. After time t2, oil 100 flows out only from inlet 52d of the two inlets 52d and 52e and is supplied to the oil tank 17. Here, in this embodiment, shaft 14 stops after a specified time tm (for example, 30 minutes) from the start of the power outage. In other words, oil needs to be supplied to oil tank 17 from the start of the power outage until the specified time tm. As shown in FIG. 5, in this embodiment, the required amount of oil is supplied to oil tank 17 (bearing 16) until the specified time tm.

Figure 6 is a diagram showing the relationship between the amount of oil (oil amount) supplied by the oil supply device in the rotating electric machine system of the comparative example and time. The oil supply device of the comparative example differs from the oil supply device 3 of the present embodiment in that only one inlet and outlet of the tank is provided. In addition, the comparative examples include a first comparative example in which the diameter of the orifice is large, and a second comparative example in which the diameter of the orifice is smaller than that of the first comparative example. The vertical axis of Figure 6 indicates the amount of oil (oil amount) supplied by the oil supply device of the comparative example during a power outage, and the horizontal axis of Figure 6 indicates the elapsed time from the time of the power outage (time in Figure 6). Lines L3 and L4 indicate the actual amount of oil (oil amount) supplied by the oil supply devices of the first and second comparative examples, respectively. Line L5 indicates the required amount (design value), which is the amount of oil (oil amount) that should be supplied by the oil supply devices of the first and second comparative examples. Note that the required amount of oil in the first and second comparative examples is the same as the required amount of oil in the present embodiment. As shown in FIG. 6, in the first comparative example, the oil in the tank 52 runs out before the specified time tm is reached, and the oil supply stops. On the other hand, in the second comparative example, the amount of oil supplied when the shaft is rotating at a relatively high speed immediately after a power outage does not reach the required amount.

Effects of the embodiment
As described above, in this embodiment, the oil supplying device 3 (oil supplying device for a rotating electric machine) supplies oil 100 to the oil tank 17 (oil supply target) of the rotating electric machine 2. The oil supplying device 3 includes the tank 52 and the guide unit 67. The tank 52 is disposed above the oil tank 17, stores the oil 100, and is provided with a plurality of inlets 52d, 52e (mouths) that are positioned differently in the up-down direction. The guide unit 67 connects the plurality of inlets 52d, 52e to the oil tank 17, and guides the oil 100 that flows out of the plurality of inlets 52d, 52e by gravity to the oil tank 17.

According to this configuration, the tank 52 is provided with a plurality of inlets 52d, 52e that are located at different positions in the vertical direction, so that the number of inlets 52d, 52e through which the oil 100 flows out of the tank 52 changes stepwise over time. Specifically, immediately after the occurrence of a power outage, oil flows out from both the inlets 52d, 52e, so that a relatively large amount of oil is supplied to the oil tank 17. As a result, the amount of oil (required amount) to be supplied to the oil tank 17 can be secured at a time when the rotation speed of the shaft 14 is relatively high immediately after the occurrence of a power outage and the amount of oil to be supplied to the oil tank 17 is relatively large. Thereafter, the outflow of oil from the inlet 52e of the inlets 52d, 52e stops, and a relatively small amount of oil flows out only from the inlet 52d. As a result, a relatively small amount of oil can be supplied to the oil tank 17 for a relatively long period of time at a time when a certain amount of time has passed since the occurrence of a power outage and the rotation speed of the shaft 14 is relatively low, and the amount of oil to be supplied to the oil tank 17 is relatively small, but the supply time of oil to the oil tank 17 is relatively long. In other words, it is easy to ensure the amount and supply time of oil to be supplied from tank 52 to oil tank 17 during a power outage.

In this embodiment, the guide section 67 includes a first portion 62a of the branched fuel supply pipe 62, a second portion 62b and a third portion 62c (piping) of the branched fuel supply pipe 62 that are connected to the multiple inlets and outlets 52d and 52e, respectively, a plurality of orifices 65a and 66a provided in the second portion 62b and the third portion 62c, respectively, and a downstream portion 61a of the main fuel supply pipe 61. The diameters of the multiple orifices 65a and 66a are larger the higher the vertical positions of the inlets and outlets 52d and 52e corresponding to the orifices 65a and 66a are.

With this configuration, the diameter of the multiple orifices 65a, 66a is larger the higher the vertical position of the inlets and outlets 52d, 52e corresponding to the orifices 65a, 66a is, so when the rotation speed of the shaft 14 is relatively high immediately after the power outage and a relatively large amount of oil needs to be supplied to the oil tank 17, the oil passes through both orifices 65a, 66a, so the amount of oil (required amount) to be supplied to the oil tank 17 can be secured. Also, when some time has passed since the power outage and the rotation speed of the shaft 14 is relatively low and a relatively small amount of oil needs to be supplied to the oil tank 17 but the time it takes to supply oil to the oil tank 17 is relatively long, a relatively small amount of oil that passes through only the orifice 65a of the orifices 65a, 66a can be supplied to the oil tank 17 for a relatively long time.

In addition, in this embodiment, the tank 52 has a side wall 52c (wall) that extends in the vertical direction. Multiple inlets and outlets 52d, 52e are provided in the side wall 52c.

With this configuration, the upper and lower positions of the entrances 52d and 52e can be made different relatively easily.

In the above embodiment, an example is shown in which two ports (inlet/outlet ports 52d, 52e) and two pipes (second portion 62b and third portion 62c) are provided, but this is not limited thereto. For example, there may be three or more ports and pipes.

Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the scope of the invention and its equivalents described in the claims.

1...rotating electric machine system, 2...rotating electric machine, 3...oil supply device (oil supply device for rotating electric machine), 17...oil tank (object to be supplied with oil), 51...electric pump, 52...tank, 52c...side wall (wall), 52d, 52e...inlet/outlet (mouth), 53...check valve, 61...main oil supply pipe, 62...branch oil supply pipe, 62b...second part (piping), 62c...third part (piping), 65a, 66a...orifice, 67...guide section, 100...oil.

Claims (3)

An oil supply device for a rotating electric machine that supplies oil to an oil supply target of a rotating electric machine,
A pump that discharges the oil;
A tank located above the oil supply target, storing the oil, and having a plurality of ports at different positions in the up-down direction;
a main oil supply pipe connecting the pump and the oil supply target and through which the oil flows;
a branch oil supply pipe that branches off from the main oil supply pipe, connects the main oil supply pipe to the plurality of ports, and through which the oil flows;
a check valve provided in the main oil supply pipe between the pump and the branch oil supply pipe, the check valve allowing the oil to flow from the pump toward the oil supply target and the tank and restricting the oil to flow from the oil supply target and the tank toward the pump;
a guide section including the main oil supply pipe between the branch oil supply pipe and the oil supply target, the branch oil supply pipe, connecting the plurality of ports to the oil supply target, and guiding the oil flowing out from the plurality of ports by gravity to the oil supply target;
Equipped with
The tank has a wall extending in the vertical direction,
The plurality of openings are provided in the wall, shifted in a width direction of the wall perpendicular to the up-down direction,
the guide portion includes a plurality of pipes that are included in the branch fuel supply pipe and connected to the plurality of ports, and a plurality of orifices that are provided in each of the plurality of pipes,
The oil supply device for a rotating electric machine, wherein the multiple orifices are located below the tank and are arranged in the width direction and are provided in the multiple pipes that are arranged in the width direction when viewed from the thickness direction of the wall perpendicular to the up-down direction and the width direction . 2 . The oil supply device for a rotating electrical machine according to claim 1 , wherein the diameters of the plurality of orifices are larger as the positions of the ports corresponding to the orifices in the vertical direction are higher. The oil supply device for a rotating electrical machine according to claim 1 or 2 ,
The rotating electric machine;
A rotating electric machine system comprising:

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