Elastic couple barring apparatus

An elastic couple barring apparatus (i.e., an elastic couple rotor turning gear) is a special tool to drive a rotor by elastic couple for adjusting a shafting center of a vertical hydroelectric generating set and other rotating devices. The elastic couple rotor turning gear is characterized in that an elastic support is mounted on a frame of the driven device, a casing being connected to the elastic support, a casing cover being firmly fixed on the casing, a speed reducer and an electric motor being installed on the cover, an output shaft of the speed reducer extending into the casing under the casing cover, the output shaft having a pinion gear mounted thereon and meshed with a gear body of a bull gear positioned in the casing, the bull gear being connected to a shaft coupling through parallel keys via a key seat or an upright post, and the shaft coupling being fixed on a rotor of the driven device. The advantages of the invention is that the structure is more reasonable, the concentricity may be adjusted more conveniently, the elastic connection makes operation easy and vibration small, deformation caused by suspending arms is eliminated, and operation's accuracy and precision are improved because the gears may be meshed and operated smoothly.

TECHNICAL FIELD

This invention relates to a special tool to drive a rotor by elastic couple for adjusting a shafting center of a vertical hydroelectric generating set and other rotating devices, and particularly to an elastic couple barring apparatus (i.e., an elastic couple rotor turning gear).

BACKGROUND OF THE INVENTION

During adjusting a shafting center of vertical hydroelectric generating set, a rotor needs to be driven by an external force so as to check the radial swinging angle of each section. Thus, an even and smooth driving rotation speed, and accurate stop points are required. Furthermore, the rotor should be in a thoroughly free status at each stop point without any disturbance external force exerting on the rotor. Moreover, it should be convenient and quick to operate in the field. However, the driving method provided by most manufacturers still employs manual driving and came hauling, which causes low safety, high labor intensity and inefficient works. The applicant of the present invention has two Chinese patents on improvement of the conventional barring method by providing a new automatic rotor turning gear: one is Chinese Patent No. 92219180.8 and the other is Chinese Patent No. 99222132.3. However, the two patents still have some shortcomings as follows. The automatic rotor turning gears have a low concentricity with the rotating devices. There is a rigid connection between the automatic rotor turning gear and a frame of the rotating device, so that a little deviation between axes of the rotor turning gear and the rotor may causes an excessive and unstable driving moment of force, which requires a long time to adjust. Arms of force of the above devices is very long and the pinion gear is assembled in a suspension arm structure, so the two structures may be easily deformed under stress to cause incorrect engagement between gears. Moreover, wires may be twisted because the motor is turned along with the device.

SUMMARY OF THE INVENTION

The purpose of this invention is to overcome the shortcomings of the above-mentioned technique and provide an elastic couple barring apparatus (i.e., an elastic couple rotor turning gear). When the apparatus is used for adjusting a shafting center of vertical hydroelectric generating set and other rotating devices, the working intensity may be reduced, working conditions may be improved, an operating adjusting time may be shortened, working efficiency and adjusting accuracy may be enhanced, and the complicated and massive generating set may be easily turned.

The purpose of this invention is achieved as follows. An elastic couple rotor turning gear is characterized in that an elastic support5is mounted on a frame6of a driven device, a casing4with a U-shaped cross section being connected to the elastic support for providing an elastic connection between the frame6of the driven device and the elastic couple rotor turning gear, a casing cover3being firmly fixed on the casing, a speed reducer2and an electric motor1being installed evenly or symmetrically positioned at an angle of 180°, an output shaft16of the speed reducer extending into the casing4under the casing cover3, the output shaft16having a pinion gear7mounted thereon and meshed with a gear body81of a bull gear8positioned in the casing, the bull gear being connected to a shaft coupling9through parallel keys10via a key seat83or an upright post84, and the shaft coupling9being fixed on a rotor12of the driven device.

The elastic support includes an upper ring51and a lower ring52. The upper ring and the lower ring are connected via a plurality of elastic ribs53. The elastic ribs53are made of elastic materials with a rectangular, groove-shaped, T-shaped, I-shape, circular or other cross section. When a little deviation occurs between the center of the elastic couple rotor turning gear and the driven rotor, a radial resisting stress caused by this deviation is eliminated by the elastic support5, which provides a convenient operation in a situation, and stable and safer running.

According to the specific structure of the rotor of the driven device, the shaft coupling9can be of an integral or separable type. When the separable type shaft coupling9is used, the shaft coupling9is connected to the rotor12of the driven device through multiple radial linkages11to make force on the rotor12of the driven device even and stab.

An axial sliding clearance13and a radial sliding clearance14are formed between the gear unit81of the bull gear and a horizontal surface and an inner wall of the casing to form a sliding bearing to ensure concentric rotation between the bull gear8and the casing4with U-shape cross section.

An air clearance is defined between the inner wall of the bull gear and the shaft coupling, and three screws15for adjusting concentricity are evenly distributed along the circumference of the shaft coupling. By adjusting the screw15, the concentricity between the stationary and rotating parts can be adjusted. The casing4is filled with lubricating oil to ensure normal operation of bearings.

The key seat83is defined on the inner wall82of the bull gear with a free rotating angle on the seat to remove the rotor of the device from external force easily and make the rotor in a fully free status. Alternatively, an upright post84is mounted on the bull gear corresponding to the parallel key10to transmit a torque. In this case, the key of the shaft coupling corresponds to the height of the upright post, so that the shaft coupling has a free rotating angle of a 180°.

The working principle of the elastic couple rotor turning gear is described as follows. When the control mechanism is powered on, the electrical motors1evenly or symmetrically in 180° position distributed along the circumference may drive the speed reducers2and pinion gears7to rotate, and the pinion gears then drive the engaged bull gears8to rotate. Pushed by equal tangential forces, and limited by the sliding bearing including the axial sliding clearance13and radial sliding clearance14, the bull gear may run smoothly. The bull gear8drives the shafting coupling9through the parallel keys10, while the shafting coupling9drives the rotor of the driven device12to rotate smoothly through the linkages11. When the elastic couple rotor turning gear rotates the driven device12and stops at a certain position, it turns back with a little angle to position the parallel key10into the free rotating angle so as to remove the rotor of the driven device from the external force. Therefore, the rotor of the driven device will be freely rotated to ensure accurate measurements. When the elastic couple rotor turning gear is installed for the first time, the concentricity between the stationary and rotating parts is adjusted by using the three screws15. After adjustment, the elastic support5is firmly mounted on the frame of the driven device6, and the three screws15for adjusting the concentricity are removed.

The present invention has following advantages. The apparatus has a more reasonable and simple structure, and it is easy to adjust the concentricity because the screws is provided at more reasonable positions. The elastic support is used instead of the conventional rigid support. Therefore, the apparatus has an improved self-stabilization performance and a small vibration during rotating, and can be operated easily. By using the casing cover, the conventional suspension arm is replaced with the fixed structure. Thus, the deformation due to the suspension arm is eliminated so that the running process of the gear engagement is smoother and the running precision and accuracy are enhanced. The gear transmission is concealed in the enclosed casing so that the apparatus can be operated safely and maintained easily and wire twisting is avoided.

DETAILED DESCRIPTION OF THE INVENTION

Detailed embodiments will be explained by reference to the accompanying figures.

Referring toFIG. 1, an elastic couple rotor turning gear is installed on a top frame6of a light hydroelectric generating set for adjusting a shafting center of the generating set. An elastic support5is connected to the top frame6of the driven device.FIGS. 2 and 3show the elastic support5including the upper ring51, the lower ring52and eight elastic ribs53between the upper and lower rings. The upper ring is a round ring with a diameter of 2.6 m and the lower ring is a round ring with a diameter of 3.8 m. The elastic ribs53are made of spring steel having a rectangular cross section. A ring-like casing4with a U-shape cross section is mounted on the elastic support. An elastic connection is established between the top frame6of the hydroelectric generating set and the elastic couple rotor turning gear. The casing4includes a casing cover3firmly fixed thereon. Two speed reducers2each with an electric motor1are installed on the casing cover and symmetrically positioned at an angle of 180° to form a couple. The speed reducer2, casing cover3and the casing4are rigidly connected together. The electric motor has a power of 1.1 KW and a rotating speed of 1500 rpm. The output rotating speed of the speed reducer is 1 rpm. The output shaft16of the speed reducer extends into the casing4under the casing cover3. A module of the pinion gear7connected to the output shaft16and a module of a bull gear8meshed with the pinion gear are both10. The gear body81of the bull gear is received in the casing4and two key seats83are defined on an inner wall82of the bull gear. Two parallel keys10are respectively received in the key seats83for connecting the bull gear8and a shafting coupling9to transmit the moment of couple.

The two parallel keys10are symmetrically positioned at an angle of 180°. According to the structure of the rotor of the driven device, the shafting coupling9is an integral type which is connected to an end of the rotor12of the driven device.

An axial sliding clearance13is defined between the gear body81in the casing and a horizontal surface of the casing to form a plane sliding friction, and an radial sliding clearance14about 0.5 mm is defined between the gear body81and an inner wall of the casing to form a sliding bearing to ensure the bull gear8concentric with the casing4.

Three screws15for adjusting concentricity between the bull gear and the shaft coupling are evenly distributed along a circumference of the shaft coupling on the inner wall of the bull gear corresponding to the shaft coupling. The casing4is filled with lubricating oil to ensure normal operation of the bearings.

This elastic couple rotor turning gear is installed on the top frame6of a heavy hydroelectric generating set for adjusting shafting center of the generating set. An elastic support5is connected to the top frame6of the driven device.FIGS. 2 and 3show the elastic support5including an upper ring51, a lower ring52and twelve elastic ribs53between the upper and lower rings. The upper ring51is a round ring with a diameter of 2.8 m, and the lower ring52is a round ring with a diameter of 4.1 m. The elastic ribs53are made of spring steel with a trough shape cross section. A ring-like casing4with a U-shape cross section is mounted on the elastic support5. An elastic connection is established between the top frame6of the hydroelectric generating set and the elastic couple rotor turning gear. The casing4has a casing cover3firmly fixed thereon. Two pairs of (four) speed reducers2each with an electric motor1are installed on the casing cover to form two couples, which synchronously and equally drive the rotor of hydroelectric generating set, wherein the two speed reducers and electric motors in each pair are symmetrically positioned at an angle of 180°. The electric motor has a power of 0.75 KW and a rotating speed of 1500 rpm. The output rotating speed of the speed reducer is 0.8 rpm. The output shaft16of the speed reducer extends into the casing4under the casing cover3. The module of the pinion gear7connected to the output shaft16and the module of the bull gear8meshed with the pinion gear are 10. The gear body81of the bull gear is received in the casing4and two key seats83are defined on an inner wall82of the bull gear. Two parallel keys10are respectively received in the key seats83for connecting the bull gear8and a shafting coupling9.

The two parallel keys10are symmetrically positioned at an angle of 180°. According to the specific structure of the rotor of the driven device, the shafting coupling9is a separable type including two parts, which is connected to the rotor12of the driven device by ten radial linkages11.

This elastic couple rotor turning gear is used for adjusting a shafting center of a super-heavy hydroelectric generating set, and includes three pairs of (six) identical speed reducers each with an electric motor to form three couples, which synchronously and equally drive the rotor of the hydraulic generating set, wherein the two speed reducers and two electric motors in each pair are symmetrically positioned at an angle of 180°.FIG. 6shows that an upright post84is mounted on the bull gear8to correspond to the parallel keys for transmitting torque. In this case, the key of the shaft coupling corresponds to the height of the upright post so that the shaft coupling has a free rotating angle of 180°. The structure of this elastic couple rotor turning gear is illustrated inFIG. 7.

Whether the number of the elastic couple rotor turning gears is even or odd, the purpose of this invention can be realized as long as the apparatuses are evenly distributed and positioned.