JPS6040783A - Protector for hydraulic machine - Google Patents

Abstract

PURPOSE:To prevent increase of hydraulic pressure in a runner chamber by operating an exchange valve in the opening direction of a movable runner blade by means of a signal from a detector for the motion of movable runner blade having no relation with the opening of flow regulation valve. CONSTITUTION:Upon breaking of wire rope 157 at point (a), the runner blade piston rod 150 will try to rotate in the closing direction independently even if there is no change of the opening of guide vane, but a weight 158 will drop to close the contact of a switchgear 162. Consequently, the solenoid 164-1 is excited to apply the pressure oil (F) onto a quick-open valve 163, to discharge the lower chamber oil of a valve servo piston 146-1. As a result, the piston 146-1 will lower while a runner blade pressure distribution plunger 146-2 will lower. Upon supply of the pressure oil (F) to the open side of servo cylinder 151, a rod 150 will maintain the open state, to enable the runner blade to rotate in the closing direction.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF APPLICATION OF THE INVENTION The present invention relates to a protection device for hydraulic machines with movable runner blades.

[Background of the invention]

Conventionally, in hydraulic machines with movable runner blades, such as Kaburan turbines and movable blade mixed flow turbines, the position (angle) of the runner blades is controlled in relation to the opening degree of the flow control valve, and a relationship is established that always provides the best efficiency. The vehicle is operated in a manner that maintains the safety. The relationship between the opening degree of this flow control valve and the angle of the runner blade is
In many cases, the runner blade has a complex functional relationship including a curve, and it is difficult to operate the runner blade directly from the flow control valve or operating servo motor via a simple lever mechanism. For this reason,
The runner blade has a dedicated servo machine groove and is configured to receive a command signal from a servo motor for a flow rate regulating valve or a control section in the preceding stage thereof, and respond by adding calculations for a cam, etc. Therefore, the command system from the flow control valve to the runner blade includes calculation and control circuits that may fail.

By the way, if the runner blade servo mechanism fails and only the runner blade suddenly rotates in the closing direction (in the direction of decreasing the flow rate), the water pressure in the runner chamber increases abnormally. Therefore, a large thrust load acts on the runner, and in some cases, the runner itself and the thrust bearing that supports the main shaft of the runner may be damaged. And this noteworthy phenomenon occurs almost instantaneously.

[Purpose of the invention]

The present invention has been made in an attempt to improve the above-mentioned drawbacks.
The purpose of this is to prevent water pressure from rising in the runner chamber and protect the runner and thrust bearing.

[Summary of the invention]

That is, a feature of the present invention is that in a hydraulic machine that controls the position of a movable runner blade while maintaining a predetermined relationship in relation to the opening degree of a flow rate control valve, the movable runner blade is connected to the flow rate control valve. A detection device that detects an operation unrelated to the opening of the runner, and a switching valve that uses a signal from the detection device to switch the pressure oil acting on the servo motor in the opening direction to operate the movable runner blade in the opening direction. It is in the protection device of the constructed hydraulic machine.

In this way, since the movable runner blade is operated in the opening direction immediately when the movable runner blade performs an operation unrelated to the opening degree of the flow rate control valve, the water pressure in the runner chamber does not increase, and the runner and thrust bearing can be protected.

[Embodiments of the invention]

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

In FIG. 1, reference numeral 1 denotes a casing, and a stay vane 2 and a guide vane 3 serving as a flow control valve are provided on the outlet side of the casing. 4 is a movable runner blade, 5 is an outer liner,
6 is the inner liner, 7 is the operating rondo, and link 9. The angle of the movable runner blade 4 is controlled via the arm 10 and lever 8. 11 is a runner boss cover, 12 is a water wheel shaft, and 13 is a runner chamber. The movable runner blade 4 is controlled to be maintained in a predetermined relationship in relation to the opening degree of the guide vane 3.

Next, the control system will be explained with reference to FIG.

101 is a governor control box which compares and calculates a speed detection signal X from a speed signal transmitter (not shown) and a feedback signal from a differential transformer coil 109 and provides an electrical signal to the transducer 102; The user 102 operates a pilot valve 103 inserted into a pilot bushing 104 up and down in response to an input electric signal. By moving up and down, this pilot valve 103 allows pressure oil A to flow into the lower chamber of the pilot servo cylinder 105, and vice versa.
5 Drain the oil from the lower chamber. Depending on the flow direction of this pressure oil A, the pilot servo piston 106 of the pilot servo cylinder 1.05 moves upward or downward. The movement of the pilot servo piston 106 is transmitted to the differential transformer core 108 via the arm 107, forming a feedback circuit. The movement of the pilot servo piston 106 is also transmitted to the lever 110, where it is compared with the actual opening degree of the guide vane servo piston 120.

If there is a difference between the two, the left end of the lever 110 will be displaced up and down, and this will cause the link 111. A valve servo pilot 113 inserted into a valve servo pilot bushing 114 is moved up and down via a lever 112. When a relative displacement occurs between the valve servo pilot 113 and the valve servo pilot bushing 114, pressure oil flows into the lower chamber of the valve servo cylinder 116, or conversely, oil is discharged. However, since the normal pressure oil C is connected to the head of the quick-closing valve 159, it does not have any influence on the above-mentioned oil passing and oil draining operations. 11 guide vane pressure regulating valve bodies are integrally attached below the valve servo cylinder 116, a valve servo piston 115-1 is attached to the valve servo cylinder 116, and a guide vane pressure regulating valve plunger is attached to the guide vane pressure regulating valve body 117. 115-
2 are inserted, and they are directly connected and move up and down as one. The movement of the valve servo piston 115-1 is controlled by lever 1.
Valve servo pilot bushing 114 through 18
will be given feedback. Valve servo piston 115 for valve servo pilot 113 that combines the above
The follow-up time constant of -1 is generally extremely short, and it appears that both move at the same time. Reference numeral 119 denotes a guide vane servo cylinder that operates the guide vane servo piston 120 by introducing pressure oil into one of the left and right chambers by the vertical movement of the guide vane pressure regulating valve plunger 115-2. The guide vane 3 is closed or opened depending on the operating direction of the guide vane servo piston 120. The operating amount of the guide vane servo piston 120, that is, the opening degree of the guide vane 3 is determined by the return ball 121, the wire rope 122. Return sheave 124, return shaft 127. return cam 1
28, is fed back to the lever 110 via the rod 129. Therefore, the rotation angle of the return shaft 127 corresponds to the opening degree of the guide vane 3. 123-1 to 12
3-3 is a pulley provided at the bending part of the wire rope 122;
25 is a wire rope attached to the return sheave 124, and a weight 126 is fixed to the end of the wire rope. 130 is a compression spring provided on the rod 129; 131 is a spring receiver; 1
33 is a cam attached to the return shaft 127, and the rotation angle of this return shaft 127 is determined by the cam 133, rod 134, . Lever 137. Link 138, lever, 139
The signal is transmitted to the three-dimensional cam rod 140 via. 135 is a compression spring provided on the rod 134; 136 is a spring receiver; 14
1 is a three-dimensional cam attached to a three-dimensional cam rod 140.

This three-dimensional cam 141 is movable in the axial direction and is set at a position corresponding to the effective head applied to the water wheel. Therefore, a runner blade opening command signal matching the head condition is given to the cam follower 142, and this is transmitted to the lever 14.
3 can be conveyed. The lever 143 compares the runner blade opening command and the actual runner blade opening signal given by the follower lever 156, and if there is a difference between the two, a signal to correct this is given as a displacement of the left end of the lever 143. It will be done. The vertical displacement of this lever 143 causes the lever to be inserted into the valve sink 145 and to move the valve plunger 144 up and down. When a relative displacement occurs between the relay valve plunger 144 and the relay valve bushing 145, the pressure oil E flows into the lower chamber of the valve servo cylinder 147, or conversely, the oil is discharged. Below the valve servo cylinder 147 is a pressure regulating valve body 148.
are integrally installed, and the valve servo cylinder 14
7 has a valve servo piston 146-1, and the pressure distribution valve body 148 has a runner blade pressure distribution valve plunger 146-1.
2 are inserted, and they are directly connected and move up and down as one. The movement of the valve servo piston 146-1 is linked to link 1.
49 to the relay valve bushing 145. The follow-up time constant of the valve servo piston 146-1 with respect to the relay valve plunger 144 is extremely short, and both move up and down almost simultaneously.

151 is a runner blade servo cylinder that guides pressure oil E into one of the upper and lower chambers by the vertical movement of the runner blade pressure regulating valve plunger 146-2, and keeps the runner blade piston rod 150 stationary.

The runner blade piston rod 150 is integrated with the operating rod 7 of the movable runner blade 4, and the vertical movement of the runner blade piston rod 150 causes the operating rod 7 to
, arm 10. Link 9. The movable runner blade 4 is rotated via a lever 8 to change its angle. Also, the position of the runner blade piston rod 150 is
57. Return sheave 152. A rod 153 and a return shaft 161 integral with the rod 153. Lever 1
54. Feedback is provided to the lever 143 via the follow lever 156.

As described above, the pilot servo piston 106 operates in response to the governor control box 101, and guide vane servo cylinder 119. A guide vane servo consisting of a guide vane servo piston 120 follows, followed by a runner blade servo cylinder 151 . A runner blade servo consisting of a runner blade piston rod 150 follows via the three-dimensional cam 141, so that the guide vane 3 and the movable runner blade 4 have a predetermined angular relationship.

Reference numeral 132 indicates a guide vane quick-closing valve which is activated by a pressure increase detection signal in the runner chamber 13, and 132-1 and 132-2 indicate solenoids thereof. 155 is a compression spring provided on the follow lever 156, 160 is a wire rope attached to the return sheave 152, and a weight 158 is attached to the end of the wire rope 160. 162 is wire rope 1
57- Or when the wire rope 160 breaks, the weight fi1
164 is a runner blade quick-open valve that is activated when the contact of the switch 162 is closed;
64-1 and 164-2 are the solenoids thereof, and 163 is a quick-opening valve operated by pressure oil from the runner blade quick-opening valve 164. When this quick-opening valve 163 is operated, the oil in the lower chamber of the valve servo piston 146-1 is is discharged via the quick-open valve 163.

Therefore, the valve servo piston 146-1 descends, and at the same time, the runner blade pressure regulating valve plunger 146-2 descends, and the open side of the runner blade servo cylinder 151 is supplied with pressure oil E.

Now, if some kind of failure occurs in the runner blade operating system from the return shaft 127 that gives the guide vane opening signal to the runner blade piston rod 150, 1. For example, if the wire rope 157 breaks at point a, the runner blade piston rod 150 tries to rotate independently in the closing direction even though there is no change in the guide vane opening degree. This is because the return sheave 152 suddenly rotates to the right, the lever 154 is pushed up, and the relay valve plunger 144 suddenly moves upward. However, wire rope 1
57 is cut, the weight 158 falls, and the switch 162
Close the contacts. For this reason, the liner blade quick-open valve 16
No. 4 solenoid 164-1 is energized, and pressure oil F acts on quick-open valve 163. When the quick-open valve 163 operates, oil in the lower chamber of the valve servo piston 146-1 is discharged via the quick-open valve 163. Therefore, the valve servo piston 146
-4 is lowered, and at the same time, the runner blade pressure regulating valve plunger 146-2 is lowered. Due to this lowering, pressure oil E is supplied to the open side of the runner blade servo cylinder 151, and the runner blade piston rod 150 is maintained in the open state. This holding prevents the movable runner blade 4 from rotating in the closing direction.

In this way, even if the wire ropes 157, 1.60 are cut, the movable runner blade 4 does not rotate in the closing direction, so in this embodiment, the water pressure in the runner chamber 13 does not rise abnormally. However, if the operation of the runner blade quick-opening valve 164 is slow for some reason, the movable runner blade 4 rotates in the closing direction, and the water pressure in the runner chamber 13 increases abnormally. This pressure increase is detected by a pressure switch (not shown) or the like, and the solenoid 132-2 of the guide vane quick-closing valve 132 is energized by a signal from the pressure switch. Due to this bias, the pressure oil C operates the quick-closing valve 159 via the guide vane quick-closing valve 132, and the oil in the lower chamber of the valve servo cylinder 116 is discharged.

Therefore, the valve servo piston 115-1 and the guide vane pressure regulating valve plunger 115-2 move downward, and pressure oil flows from the guide vane pressure regulating valve body 117 into the pressure chamber of the guide vane servo cylinder 119. Thus, the guide vane servo piston 120 is operated, and the guide vane 3 connected to the guide vane servo piston 120 is closed.

〔Effect of the invention〕

According to the present invention, when the movable runner blade performs an operation that is not related to the opening degree of the flow control valve, the movable runner blade is operated in the opening direction, so there is no rise in water pressure in the runner chamber, and the runner and thrust bearing are protected. be able to.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a main part of a Kablan water turbine having movable runner blades showing an embodiment of the hydraulic machine of the present invention, and FIG. 2 is a control system diagram of the protection device of the present invention. 3... Guide vane, 4... Movable runner blade,
13...Runner chamber, 120...Guide vane servo cylinder, 144...Relay valve plunger, 14
5... Relay valve bushing, 146-1... Valve servo piston, 147... Valve servo cylinder, 150... Runner blade piston rod, 15
1...Runner blade servo cylinder, 15'7,1
60... Wire rope, 162... Weight, 163.
...Sudden opening valve, 164...Runner blade sudden opening and closing.

Claims (1)

[Claims] 1. In a hydraulic machine that controls the position of a movable runner blade while maintaining a predetermined relationship in relation to the opening degree of a flow control valve,
A detection device detects when the movable runner blade performs an operation unrelated to the opening degree of the flow control valve, and a signal from this detection device switches the pressure oil acting on the servo motor in the opening direction to open the movable runner blade. A protection device for hydraulic machinery characterized by comprising a switching valve that can be operated in one direction.