JP2802500B2 - Runner vane operating mechanism of movable wing turbine - Google Patents

Description

The present invention relates to a runner vane operating mechanism for a movable wing turbine,
In particular, the present invention relates to a runner vane operating mechanism using a vertically movable runner servomotor.

[Conventional technology]

As a method of operating the runner vanes of the mixed flow type water turbine,
The runner servomotor may be of a rotary type or may be of a vertical type.

In the rotary type, the runner vane operating shaft is rotated by a runner servomotor, and the runner vane is operated by the rotating runner vane operating shaft. In this method, the structure of the runner servomotor is complicated, oil leakage from the runner servomotor is large, and it is difficult to obtain the target operating force. Absent.

On the other hand, in the vertical type, the runner vane operating shaft is moved up and down by a runner servo motor, and the runner vane is operated by the runner vane operating shaft which moves up and down. However, this method requires a complicated operating mechanism to transmit the force of the runner vane operating shaft that moves up and down to the runner vane.

Incidentally, a simplified version of such a complicated operation mechanism is disclosed in JP-A-59-147778 and JP-A-60-162073. Was never actually used.

[Problems to be solved by the invention]

As described above, when a runner servomotor is of a vertical type, the runner vane operation mechanism is complicated. For this reason, the conventional runner vane operating mechanism has a possibility of deteriorating reliability, and maintenance work is also difficult.

In addition, since all the components constituting the runner vane operating mechanism are arranged above the runner vane stem, a runner upper cover for storing these components is required, so that the weight increases and the cost increases, and the overall height of the runner increases. Therefore, the mounting position of the main bearing is increased. As a result, the runner overhang dimension becomes large and the shaft vibration characteristics deteriorate. In other words, when the runner overhang increases, the bending deformation of the main shaft with respect to the hydraulic and mechanical unbalance loads acting on the runners increases, causing a reduction in the critical speed due to a decrease in the bending rigidity of the main shaft in this portion, and tends to cause resonance. It becomes an axis system. In such a case, it is a general method to cope with the problem by increasing the diameter of the main shaft, but it is not always sufficient and there is an economical problem.

It is an object of the present invention to provide a runner vane operating mechanism for a movable wing turbine that has a simple structure and can be reduced in size when a vertical runner is used as a runner servomotor.

[Means for solving the problem]

In order to achieve the above object, the present invention provides a runner vane operating shaft arranged in a rotary main shaft of a water turbine having a movable vane runner vane attached to a lower end thereof, and rotating the runner vane operating shaft to thereby provide the runner vane. In a runner vane operating mechanism of a movable wing turbine for controlling an opening degree, a movable portion provided on a rotating main shaft of the turbine and moving in a vertical direction, and fixed to a lower portion of the movable portion and obliquely attached to a peripheral surface which is an outer peripheral surface. A cylindrical portion having a groove formed therein, and engaging with the groove,
A rotating portion that applies a rotating force to the runner vane operating shaft in accordance with the vertical movement of the cylindrical portion, a runner vane operating lever that rotates the runner vane of the movable wing, and a runner vane disposed at a lower end of the runner vane operating shaft; The operation lever is provided with a rotation operation force transmission lever for transmitting the rotational power of the runner vane operation shaft.

Also, a thrust roller bearing may be provided between the peripheral surface of the rotating part and the inner surface of the rotary spindle, or the end face of the rotating part may be locked to prevent the rotating part from moving in the vertical direction. It is preferable to provide a plate having a lubricating oil groove between the stepped portion of the rotating spindle and the stepped portion.

Furthermore, in order to stop the movable part from rotating,
It is preferable that a key is fixed to the movable portion, and a key groove in which the tip of the key slides is formed on the inner surface of the rotary spindle.

[Action]

According to the above configuration, when the movable portion is moved upward or downward in the rotary main shaft, the cylindrical portion fixed to the movable portion moves in the rotary shaft in the same direction as the movable portion. When the cylindrical portion moves upward or downward, a slanting groove is formed on the outer peripheral surface of the cylindrical portion, and the turning portion that engages with the slanting groove turns around its axis. Then, the turning power is transmitted to the runner vane operation shaft, and operates the opening degree of the runner vane.

Also, if a thrust roller bearing is provided between the outer peripheral surface of the rotating part and the inner surface of the rotary spindle, or a plate having a lubricating oil groove is provided between the end surface of the rotating part and the stepped portion of the inner surface of the rotary spindle. ,
When the cylindrical portion moves up and down, the turning portion is locked from moving in the up and down direction and turns smoothly.

Furthermore, if the key is fixed to the movable part and a key groove in which the tip of the key slides is formed on the inner surface of the rotating main shaft, when the cylindrical part moves up and down, the cylindrical part is moved from one of the rotating parts. The cylindrical portion is prevented from rotating even if it receives a reaction force trying to rotate in the direction of.

〔Example〕

 An embodiment of the present invention will be described below with reference to the drawings.

The operation mechanism of the runner vane according to the present invention is shown in FIG. 1 and FIG. As shown in the figure, the main shaft 6 having the runner vanes 1 at the lower end and the generator shaft 25 are connected via a runner servo cylinder 31. An inner oil supply pipe 24 is provided in a hollow portion of the generator shaft 25, and a runner servo piston 17 is provided in a runner servo cylinder 31. Inside and outside of the inner oil supply pipe 24, pressure oil from a pressure oil introducing device (not shown) flows, and this pressure oil is supplied to a runner servo upper chamber 26 and a runner servo lower chamber above and below the runner servo piston 17. Each is pumped to 27. Then, by changing the flow direction of the pressure oil, the runner servo piston 17 can be moved in the vertical direction.

Key 3 is provided on the lower projection 17A of the runner servo piston 17.
2 is fixed, and the tip of the key 32 can slide in a key groove 31A formed on the inner surface of the runner servo cylinder 31.

Further, a cylindrical oblique spline pinion 28 having an oblique spline formed on the outer peripheral surface is fixed below the protruding portion 17A of the runner servo piston 17, and moves vertically with the runner servo piston 17. ing. The spline on the outer peripheral surface is formed by being twisted around the central axis, and when viewed from the horizontal direction, the spline is inclined at a twist angle θ. The oblique spline pinion 28 meshes with the oblique spline gear 30. Bevel spline gear
30 has a cylindrical shape with both ends closed, and an oblique spline that meshes with the oblique spline pinion 28 is formed at the center of one end surface thereof. The outer peripheral surface of the oblique spline gear 30 is fixed to the runner servo cylinder 31 via the thrust roller bearing 12 and the holding plate 29.

A runner vane operating shaft 13 is provided in the main shaft 6, and the upper end of the runner vane operating shaft 13 is fixed to the oblique spline gear 30. A crosshead 14 is attached to the lower end of the runner vane operation shaft 13 as a rotation operation force transmission lever for transmitting rotation, and the crosshead 14 is connected to the runner vane operation lever 7 via a slider block 10 and a slider block pin 9. The tip of the runner vane operating lever 7 is connected to the runner vane 1.

In the drawing, reference numeral 33 denotes an operation shaft retainer that supports the runner vane operation shaft 13, and reference numeral 35 denotes an oil communication hole.

The main shaft 6, the generator shaft 25 and the runner servo cylinder 31 constitute a rotating main shaft, the runner servo piston 17 constitutes a movable portion, the oblique spline pinion 28 constitutes a cylindrical portion, and the oblique spline gear 30 constitutes a rotating portion. .

 Next, the operation of the present embodiment will be described.

When the pressurized oil is sent from a pressurized oil introducing device (not shown) to move the runner vane 1, the pressurized oil passes through the inside or outside of the oil supply pipe 24 to the runner servo upper chamber 26 and the lower chamber 27, and the runner servo piston Move 17 up and down. On this occasion,
When the runner vane 1 is opened, the runner servo piston 17 is vertically moved upward by introducing pressure oil into the lower runner servo chamber 27 and depressurizing (discharging) the upper runner servo chamber 26. When the runner vane 1 is to be tightened, the runner servo piston 17 is vertically moved downward by sending pressure oil to the runner servo chamber 26 and depressurizing the runner servo lower chamber 27.

When the runner servo piston 17 moves up and down (arrow A in FIG. 2), the oblique spline pinion 28 moves up and down,
The oblique spline gear 30 meshing with the oblique spline pinion 28 rotates around its axis (arrow B in the figure) because the movement in the vertical direction is restricted by the pressing plate 29. In addition, since a key is provided between the runner servo piston 17 and the runner servo cylinder 31, the runner servo piston 17 is prevented from rotating when the runner servo piston 17 moves up and down.

If the twist angle θ of the oblique spline pinion 28 exceeds 45 degrees, it becomes logically inoperable. Therefore, it is important that the twist angle θ is always 45 degrees or less. The smaller the torsion angle θ, the greater the rotational power due to the wedge effect, but the greater the stroke of the runner servo piston 17 that moves up and down. Therefore, the minimum torsion angle θ is required to be 5 degrees. . Therefore, the twist angle θ is preferably set in the range of 5 to 45 degrees.

In addition, the twist angle θ can be inclined to the right as opposed to FIG. By doing so, the oblique spline pinion 28
Is moved up and down, the rotation direction of the oblique spline gear 30 is reversed.

According to the present embodiment, the runner vane is operated by rotating the runner vane operation shaft.
Compared to the conventional case where the runner vane is operated by moving the runner vane operating shaft up and down, the lever,
The number of parts such as links can be significantly reduced. That is, in contrast to the conventional three-lever, one-link, and one-slider block for one runner vane, the present embodiment can use a one-lever, one-slider block.

Further, if the number of parts is reduced as described above, the lower portion of the runner vane operation shaft is simplified, so that the runner overhang dimension H (see FIG. 1) can be reduced. That is, H / D ≒ 0.7 to 0.8 in the conventional water turbine, whereas H / D ≒ 0.4 to 0.6 can be reduced in the present embodiment. As a result, an improvement in the shaft vibration characteristics can be achieved.

Next, another embodiment of the present invention is shown in FIG. 3 and FIG. Both figures are examples in which the method of receiving the thrust of the oblique spline gear 30 is modified.

In FIG. 3, the outside of the oblique spline gear 30 is supported by a bearing 36, and an upper thrust receiving plate 37 is provided between the upper end surface of the oblique spline gear 30 and the stepped portion 31B of the runner servo cylinder 31. The upper thrust receiving plate 37 is provided with lubricating oil grooves at several locations along the circumferential direction to improve lubrication characteristics.

FIG. 4 shows a case where only the upper thrust receiving plate 37 is provided on the upper end surface of the oblique spline gear 30.

According to the embodiment shown in FIG. 3 or FIG. 4, the thrust receiver of the oblique spline gear 30 can have a simple structure, which is very economical.

〔The invention's effect〕

As described above, according to the present invention, the runner overbang dimension can be reduced, so that the shaft vibration characteristics are improved and the outer diameter dimension of the main shaft can be reduced by about 5 to 10%.

In addition, since the runner vane operation mechanism is simplified, there is an effect of reducing the weight and cost of the operation mechanism.

Furthermore, since the runner boss can be miniaturized, the area in contact with water is reduced, and mechanical loss due to rotation can be reduced,
The overall turbine efficiency can be improved.

In addition, since the oblique spline mechanism is provided in the runner servo cylinder, the inside of the runner boss is made oil-free, so that it is possible to prevent water from being contaminated with oil.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a runner vane operating mechanism according to the present invention, FIG. 2 is a detailed view of a runner servo unit, and FIGS. 3 and 4 are diagrams corresponding to FIG. 2 showing another embodiment. 1 ... runner vane, 6 ... spindle, 7 ... runner vane operating lever, 9 ... slider block pin, 10 ...
Slider block, 12 ... Thrust roller bearing, 13 ...
Runner vane operating shaft, 14 ... Cross head, 17 ... Runner servo piston, 24 ... Inner oil supply pipe, 25 ... Generator shaft, 26 ... Runner servo upper chamber, 27 ... Runner servo lower chamber, 28 ... Diagonal spline pinion , 29 ... Presser plate, 30
... oblique spline gear, 31 ... runner servo cylinder, 32 ... key, 33 ... operating shaft presser, 35 ... oil communication hole,
36 ... Bearing, 37 ... Thrust support plate on top.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Hiroshi Sato 3-1-1 Sachimachi, Hitachi-shi, Ibaraki Pref. Hitachi, Ltd. Hitachi Plant (56) References JP-A-60-153479 (JP, A) 1979-101172 (JP, U) Jiko 37-6204 (JP, Y1) JPO, “Technical Trend Series Handbook of Machine Elements from the Viewpoint of Patent [Shaft, Bearing, Spring, Buffer]”, Invention Association, (February 1, 1982), P.S. 175-P. 176 (58) Field surveyed (Int.Cl. ⁶ , DB name) F03B 3/14

Claims (4)

(57) [Claims] 1. A runner vane operating shaft is disposed in a rotating main shaft of a water turbine having a movable vane runner vane attached to a lower end thereof.
In a runner vane operating mechanism of a movable wing turbine that operates an opening of the runner vane by rotating the runner vane operating shaft, a movable portion that is provided on a rotating main shaft of the turbine and moves in a vertical direction; A cylindrical portion fixed to the lower portion and having a slanted groove formed on the peripheral surface, a rotating portion that engages with the groove, and applies a rotating power to the runner vane operating shaft according to the vertical movement of the cylindrical portion, A runner vane operation lever for rotating the runner vane of the movable wing; and a rotation operation force transmission lever disposed at a lower end of the runner vane operation shaft and transmitting the rotational power of the runner vane operation shaft to the runner vane operation lever. A runner vane operating mechanism for a movable wing turbine. 2. A runner vane operating mechanism for a movable wing turbine according to claim 1, wherein said rotation portion is locked on a peripheral surface of said rotation portion and an inner surface of said rotary spindle in order to lock said rotation portion from moving in a vertical direction. A runner vane operating mechanism for a movable vane turbine, wherein a thrust roller bearing is provided between the runner vanes. 3. The runner vane operating mechanism for a movable wing turbine according to claim 1, wherein the stepped portion between the end surface of the rotating portion and the rotating main shaft is provided to stop the rotating portion from moving in the vertical direction. A runner vane operating mechanism for a movable vane turbine, wherein a plate having a lubricating oil groove is provided between the runner vane and the lubricating oil turbine. 4. A runner vane operating mechanism for a movable wing turbine according to claim 1, wherein a key is fixed to said movable portion so as to lock said movable portion from rotating, and a tip of said key is slid. A runner vane operating mechanism for a movable wing turbine, wherein a moving key groove is formed on an inner surface of the rotary spindle.