JPS6221992B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a bearing device for a water wheel shaft of a hydroelectric generator or an electric water pump, and particularly to a bearing device for a movable runner blade of a Kaplan water turbine, a cylindrical water turbine, a diagonal flow water turbine, etc. The present invention relates to a structure of a bearing device for supporting a lateral load of a water turbine shaft.

[Conventional technology]

First, the arrangement of the conventional water turbine bearing device and the pressure oil introduction device for driving the movable runner blades was
This will be explained with reference to the figures.

In FIG. 1, a runner boss 14 is fastened to the lower end flange portion of a water wheel shaft 12 extending downward from a hydroelectric generator or an electric water pump, and a plurality of radially projecting runner blades 16 are rotated on the runner boss. It is mounted movably (pitch angle can be changed). A servo motor (not shown) driven by pressure oil supplied through the water wheel shaft from a pressure oil introduction device, which will be described later, is housed in the runner boss, and the servo motor drives the runner blades 16. The angle is adjusted.

Speed ring 1 fixed to water turbine pit wall 6
An upper cover 20 and a lower cover 22 are attached to the speed ring 8, and guide vanes 26 facing each of a plurality of stay vanes welded inside the speed ring 18 are supported by these upper and lower covers. Reference number 28 indicates a spiral casing welded to speed ring 18.

Therefore, in the prior art, the bearing device (main bearing device) 30 that supports the lateral load of the water turbine shaft 12 is provided below and relatively close to the runner blades 16, and the pressure oil introduction device 32 for adjusting the angle of the runner blades was provided separately and independently from the bearing device 30 at a relatively upper position.

In the example shown in FIG. 1, the bearing device 30 is composed of a bearing metal 34 that slides on the circumferential surface of the water turbine shaft, a case 36 that defines an oil reservoir, etc., and a bearing device support 38 that protrudes inward from the upper cover 20. It has been well supported.

On the other hand, the pressure oil introducing device 32 is composed of a body 40 disposed around the water wheel shaft, a closed side pressure oil pipe 42A and an open side pressure oil pipe 42B connected to the body, a case 44 surrounding the whole, etc. It is supported by a pressure oil introduction device support 46 that projects inwardly from 6 . Two hydraulic oil supply holes 48A, 48B are formed in the body 40, and each hydraulic oil introduction hole 50A, 50 opens on the circumferential surface of the water wheel shaft to allow the pressure oil from the respective pressure oil pipes 42A, 42B to flow.
It is arranged so that it is sent to B alternately. The pressure oil introduced from the hydraulic oil introduction hole 50A or 50B is
The hydraulic oil is supplied through the hydraulic oil passage 52A or 52B in the water wheel shaft 12 to a servo motor for driving runner blades in the runner boss 14, and adjusts the angle of the runner blades 16.

An oil leakage pipe 54 is provided on the lower surface of the case 44 of the pressure oil introducing device, and a water sealing mechanism 56 attached to the upper cover 20 is provided on the lower side of the bearing device 30.

[Problem that the invention seeks to solve]

In the conventional structure described above, the pressure oil introduction device 32 for introducing pressure oil into the water wheel shaft and the bearing device 30 for supporting the lateral load acting on the water wheel shaft are installed separately and independently at different locations. As a result, the structure of the water turbine was complicated and maintenance and inspection was difficult. Further, there were problems in that the product was heavy and the manufacturing cost was high.

The present invention aims to solve the problems of the conventional technology, and by integrating the pressure oil introducing device and the bearing device, it is possible to simplify the structure of the water turbine, facilitate maintenance and inspection work, and reduce the weight. The present invention also provides a bearing device for a water wheel shaft that can reduce manufacturing costs.

Furthermore, the present invention provides a bearing device for a water turbine shaft that suppresses expected vibrations of the bearing portion and obtains a large vibration damping effect by integrating the pressure oil introducing device and the bearing device.

[Means for solving problems]

According to the present invention, a pair of hydraulic oil passages are provided inside the water wheel shaft along the axial direction, and pressurized oil is supplied from each of the pair of hydraulic oil introduction holes opened on the circumferential surface of the water wheel shaft to each of the hydraulic oil passages. In a bearing device used for a water turbine shaft, the angular position of a runner blade attached to the water turbine shaft is adjusted via a servo motor driven by pressure oil, the bearing slidingly contacts the circumferential surface of the water turbine shaft. A bearing body having a surface and having shaft seal packings at both ends in the axial direction is provided, and the hydraulic oil introduction hole is formed in a portion between each of the shaft seal packings corresponding to the bearing body of the water turbine shaft. A pair of hydraulic oil supply holes opening into the bearing surface are formed between the shaft seal packings of the bearing body, and pressure oil is supplied from each of the hydraulic oil supply holes to each of the hydraulic oil introduction holes. and a pocket is formed in the double shaft sealing packing on the bearing surface of the bearing body and the hydraulic oil supply hole, and pressure oil is supplied to the pocket through the oil supply hole formed in the bearing body. A bearing device for a water turbine shaft having features is provided.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 2 and 3.

In these drawings, the same reference numerals as those in FIG. 1 indicate the same or corresponding parts, respectively.

2 and 3 show a first embodiment of the present invention, in which a bearing device 100 is installed at a position relatively below the water wheel shaft 12 and close to the runner blades 16. As shown in FIG. The bearing assembly is supported by a bearing assembly support 102 that projects inwardly from the upper cover 20.

The bearing device 100 has a bearing body 104 arranged around the water wheel shaft, and is attached to the upper cover 20 by fastening a flange portion 104A formed on the body to the support 102. A liner 106 made of a bearing alloy or the like is integrally joined to the inner circumferential bearing surface of the body 104, and is in sliding contact with the circumferential surface of the water turbine shaft.

On the circumferential surface of the water turbine shaft corresponding to the bearing body 104,
Hydraulic oil introduction hole 50A for introducing closing side pressure oil
A hydraulic oil introduction hole 50B for introducing open-side pressure oil is formed in the body 104, and hydraulic oil supply holes 48A and 48B are formed in the body 104 and open to the bearing surface and communicate with the hydraulic oil introduction holes 50A and 50B, respectively. ing.

A closed side pressure oil pipe 42A and an open side pressure oil pipe 42B are connected to the outside of the body 104, and pressure oil is supplied from the closed side pressure oil pipe 42A into the water axle through the hydraulic oil supply hole 48A and the hydraulic oil introduction hole 50A, and the open side pressure oil pipe 42B. Pressure oil is alternately supplied into the water wheel shaft through the other working supply hole 48B and the working oil introduction hole 50B through separate routes.

A hydraulic oil pipe 108 that is slidable in the axial direction is fitted into the water wheel shaft 12, and inside and outside of the hydraulic oil pipe there is a closed side hydraulic oil passage 110A and an open side hydraulic oil passage 110B.
is formed. The closed side hydraulic oil passage 110A communicates with one hydraulic oil introduction hole 50A through an opening formed in the hydraulic oil pipe 108, and the open side hydraulic oil passage 1
10B communicates with the other hydraulic oil introduction hole 50B. In this way, the hydraulic pressure from the hydraulic source is passed through the closing side pressure oil pipe 42A to the closing side hydraulic oil passage 11 in the water wheel shaft.
0A, the servo motor is driven to the closing side and the runner blade 16 is rotated to the closing side. Conversely, if hydraulic pressure is supplied to the opening side hydraulic oil passage 110B through the opening side pressure oil pipe 42B, the servo motor is driven to the opening side. The runner blade 16 is rotated toward the opening side.

Incidentally, shaft sealing packings 112A, 112 are provided at the upper and lower ends of the bearing body 104 in sliding contact with the circumferential surface of the water turbine shaft.
B is provided. Further, the entire bearing device is covered by a case 114.

As shown in FIG. 2, an oil leakage pipe 116 is attached to the lower part of the case 114, so that when the pressure oil leaks through the bearing surface, it is returned to the tank. Furthermore, oil drains 118A and 118B are provided at appropriate positions above and below the bearing device 100 to prevent oil from scattering in the water turbine pit.

Furthermore, the peripheral portion of the bearing body 104 in the bearing device 100 will be further explained using FIG.
In the figure, pockets 120A and 120B are provided on the inner surface of the bearing body 104, that is, the bearing surface, and oil supply pipes 122A and 122 are provided in each pocket.
B and oil supply hole 124 formed in the bearing body
Pressure oil is supplied through A and 124B. The pockets 120A and 120B formed at the upper and lower parts of the bearing surface are each formed by a plurality of recesses (for example, 4 recesses) provided at appropriate intervals in the circumferential direction, and are capable of retaining hydraulic pressure therein. It's becoming like that. That is, by supplying hydraulic pressure to each pocket 120A, 120B, a static pressure pocket is formed, and the pocket functions as a static pressure bearing.

A position slightly away from each of the upper and lower pockets on the bearing surface (bearing sliding surface of the bearing body), in the example of the drawing, between each pocket and the hydraulic oil supply holes 48A, 48B.
Oil drain hole 126A formed in bearing body 104,
126B is open. Therefore, oil leaking from each pocket onto the bearing sliding surface is returned to the oil collection tank from each oil drain hole through the oil drain pipes 128A, 128B.

According to the bearing devices shown in FIGS. 2 and 3, the conventional pressure oil introduction device for driving runner blades (pressure oil introduction device 32 in FIG. 1) is housed in the bearing device 100, so that the water turbine The structure can be made extremely simple, and its maintenance and inspection can also be facilitated. Moreover, the effects of weight reduction and manufacturing cost reduction can also be obtained.

Furthermore, since the hydraulic oil supply holes 48A and 48B are opened in the bearing surface that contacts the circumferential surface of the water turbine shaft 12, high-pressure hydraulic oil appropriately permeates into the bearing surface during operation of the water turbine. Therefore, the bearing surface can be lubricated by this hydraulic oil without providing a separate lubricating oil reservoir or the like. In addition, since the hydraulic oil that enters the bearing surface is under high pressure, the hydraulic oil introduced between the sliding surfaces generates an oil film pressure equivalent to the lateral load acting on the water turbine shaft, and the bearing supports this lateral load. It can also perform functions.

Further, since the hydrostatic bearing can hold a high hydrostatic pressure in each pocket, a bearing device for a water wheel shaft with high rotational accuracy and high reliability is provided.
The reason for this is that, for example, in a sliding bearing without the pocket, the load is supported by the pressure generated in the wedge-shaped oil film formed between the rotating shaft (water wheel shaft) and the bearing surface, whereas This is because the static pressure pocket has a high load supporting capacity and can prevent contact between the rotating shaft and the fixed part.

Furthermore, the oil pressure of each oil supply pipe 122A, 122B is the pressure oil pipe 42A, 42B for driving the runner blade.
Because it can be extracted from a common hydraulic source,
Each pocket can be refueled with very high oil pressure. In the case of hydrostatic bearings, the higher the supplied oil pressure, the greater the load capacity can be given, and the rotation accuracy of the rotating shaft is higher, and moreover, a highly reliable bearing with less contact between the bearing sliding surfaces can be obtained. Therefore, a bearing device for a water turbine shaft having a high load capacity and excellent reliability can be obtained.

〔Effect of the invention〕

As is clear from the above description, according to the present invention,
The pressure oil introduction device for driving the runner blades and the water wheel bearing device are integrated, and the bearing device has both functions, which simplifies the structure of the water wheel, makes maintenance and inspection easier, and reduces weight and manufacturing costs. can be achieved.

Furthermore, since the pressure oil for driving the runner blades can be used to lubricate the bearing surface, there is no need to provide a separate lubrication device.

Furthermore, since the pressure of high-pressure hydraulic oil is directly supplied to the static pressure maintenance pocket groove on the inner surface of the bearing, a large vibration damping effect can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional side view showing the structure of a conventional water turbine shaft bearing device and pressure oil introduction device, and FIG. 2 is a partially sectional side view showing a water turbine equipped with the water turbine shaft bearing device of the present invention. FIG. 3 is an enlarged longitudinal sectional view showing the main parts of the bearing device for a water turbine shaft of the present invention. 12...Water wheel shaft, 16...Runner blade, 20
...Top cover, 42A, 42B...Pressure pipe, 48A,
48B... Hydraulic oil supply hole, 50A, 50B... Hydraulic oil introduction hole, 100... Bearing device, 104... Bearing body, 106... Liner (bearing surface), 108... Hydraulic oil pipe, 110A, 110B... Hydraulic oil passage, 112
A, 112B...shaft seal packing, 120A, 12
0B...Pocket, 122A, 122B...Oil supply pipe,
124A, 124B...Oil supply hole, 126A, 126
B...Oil drain hole, 128A, 128B...Oil drain pipe.

Claims (1)

[Claims] 1 A pair of hydraulic oil passages are provided inside the water wheel shaft along the axial direction, and pressure oil is supplied to each of the hydraulic oil passages from each of the pair of hydraulic oil introduction holes opened on the circumferential surface of the water wheel shaft. A bearing device used for a water turbine shaft in which the angular position of a runner blade attached to the water turbine shaft is adjusted via a servo motor driven by pressure oil, the bearing device having a bearing surface that comes into sliding contact with the circumferential surface of the water turbine shaft, A bearing body is provided with shaft seal packings at both ends in the axial direction, and the hydraulic oil introduction hole is formed in a portion between each of the shaft seal packings corresponding to the bearing body of the water turbine shaft. A pair of hydraulic oil supply holes opening into the bearing surface are formed between the shaft seal packings, and pressure oil is supplied from each of the hydraulic oil supply holes to each of the hydraulic oil introduction holes, and the bearing A pocket is formed between the double shaft sealing packing on the bearing surface of the body and the hydraulic oil supply hole, and pressure oil is supplied to the pocket through the oil supply hole formed in the bearing body. Axle bearing device.