A low-resistance detachable crank connecting rod mechanism applied to a reversing turbine

Abstract

The application provides a low-flow-resistance detachable crank connecting rod mechanism applied to a reverse turbine, which comprises a Y-shaped crank, a rotating shaft and an open connecting rod, innovatively designs a rectangular boss on one side of the rotating shaft and a rectangular groove on the Y-shaped crank, and fixes the rotating shaft and the Y-shaped crank together through interference fit, avoids connecting through a traditional bolt and nut mode, improves structural reliability, reduces the area of a gas flow position blocking gas, and reduces the flow resistance of gas. On the basis, the rotating shaft is provided with a thick plate structure with arc-shaped ends at the middle position, and the connecting rod is designed in an open form, so that the thick plate on the rotating shaft can be inserted into the opening on the open connecting rod at a specific angle, the assembly of the crank connecting rod mechanism is completed, the disassembly can also be completed through the opening, and the disassembly cannot be completed within the working angle range. The application has the advantages of simple structure, high stability, small resistance to gas, and the ability of completing the assembly and disassembly of the crank connecting rod without disassembling the rotating shaft.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of marine gas turbines and is applied to a low-flow-resistance detachable crank connecting rod mechanism applied to a reverse turbine. BACKGROUND

[0002] The reversible gas turbine is favored by various countries due to its large reverse power density, rapid start and other characteristics, and becomes one of the main power devices of ships. The reversible gas turbine adopts the design idea of double gas passages + double-layer turbine blades. The outer passage is a reverse passage. The inner passage is a forward passage, and the distribution of the gas flow route is realized through a gas switching mechanism at the front end. When the gas only flows through the lower turbine blades, the turbine rotor rotates forward, and when the gas only flows through the upper turbine blades, the turbine rotor rotates reversely. The switching of the gas is realized through the switching mechanism at the front end of the turbine. The switching mechanism mainly consists of an electric cylinder, a crank connecting rod mechanism and a baffle. The electric cylinder drives the baffle to rotate through the crank connecting rod mechanism, and the change of the gas flow direction is completed, that is, the baffle is adjusted to make the gas flow into the forward passage or the reverse passage. The crank connecting rod mechanism for driving the baffle to move is in the gas passage, and a great disturbance to the uniform flow of the gas and a great flow loss are caused, which affects the performance of the turbine. Therefore, the cross-sectional area of the crank connecting rod mechanism is designed to be as small as possible to reduce the flow resistance of the gas. In addition, the threaded connection at the connecting position of the crank connecting rod mechanism is reduced as much as possible to avoid the corrosion of the high-temperature gas to the threads and cause the connecting failure of the crank connecting rod mechanism. The broken parts falling into the gas flow passage can injure the turbine blades behind, causing a major accident.

[0003] In order to obtain a crank connecting rod mechanism with small flow resistance, reliable connection and convenient disassembly, the application provides a low-flow-resistance detachable crank connecting rod mechanism applied to a reverse turbine. SUMMARY

[0004] In order to solve the problems of the traditional crank connecting rod mechanism, such as large flow resistance, unreliable connection and inconvenient disassembly, the application provides a low-flow-resistance detachable crank connecting rod mechanism applied to a reverse turbine.

[0005] The purpose of the application is achieved in that the mechanism mainly consists of a Y-shaped crank, a rotating shaft and an open connecting rod. A rectangular boss is designed on one side of the rotating shaft, and a rectangular groove is designed on the Y-shaped crank. The rotating shaft and the Y-shaped crank are fixed together through interference fit. The rotating shaft is in the form of a thick plate with arc-shaped ends at the middle position. The connecting rod is designed in the form of an opening, so that at a specific angle, the opening on the open connecting rod can be inserted into the thick plate on the rotating shaft to complete the assembly of the crank connecting rod mechanism. The opening can also be used for disassembly, but the mechanism cannot be disassembled within the working angle range.

[0006] Further, the thermal expansion coefficient of the rotating shaft material is greater than the thermal expansion coefficient of the Y-shaped crank material, so that the interference state is always maintained under high temperature working conditions.

[0007] Further, the opening size L on the open connecting rod should be greater than the size L1 of the rotating shaft middle thick plate.

[0008] Compared with the prior art, the beneficial effects of the present application are: the low-flow-resistance detachable crank connecting rod mechanism applied to the reverse turbine proposed by the present application uses interference fit to complete the assembly of the crank and the rotating shaft, avoids the use of threaded connection, ensures the reliability of long-time work, and the structure has the smallest cross-sectional area, reducing the gas flow resistance. The connecting rod with an opening makes disassembly more convenient. The rectangular boss is designed on one side of the rotating shaft, and the rectangular groove is designed on the Y-shaped crank, and the rotating shaft and the Y-shaped crank are fixed together through interference fit, avoiding the use of traditional bolt and nut connection, improving the structural reliability, and reducing the area of the gas flow position blocking the gas, reducing the gas flow resistance. On this basis, the thick plate structure with arc-shaped ends is arranged at the middle position of the rotating shaft, and the connecting rod is designed in an open form, so that at a certain angle, the thick plate on the rotating shaft can be inserted through the opening on the open connecting rod to complete the assembly of the crank connecting rod mechanism, and the disassembly can also be completed through the opening, but it cannot be disassembled within the working angle range. BRIEF DESCRIPTION OF DRAWINGS

[0009] Figure 1 The switching mechanism installation structure of the present application is shown in the figure;

[0010] Figure 2 The three-dimensional structure schematic diagram of the crank connecting rod mechanism of the present application is shown in the figure;

[0011] Figure 3 The crank connecting rod mechanism installation section view of the present application is shown in the figure;

[0012] Figure 4 The three-dimensional structure schematic diagram of the Y-shaped crank of the present application is shown in the figure;

[0013] Figure 5 The three-dimensional structure schematic diagram of the open connecting rod of the present application is shown in the figure;

[0014] Figure 6 The three-dimensional structure schematic diagram of the rotating shaft of the present application is shown in the figure;

[0015] Figure 7 The rotating shaft middle position section view of the present application is shown in the figure;

[0016] Figure 8 The open connecting rod installation schematic diagram of the present application is shown in the figure;

[0017] In the figure: electric cylinder 1, crank connecting rod mechanism 2, baffle 3, outer machine case 4, middle machine case 5, inner machine case 6, air inlet section 7, Y-shaped crank 8, rotating shaft 9, open connecting rod 10, rectangular groove 8-1, rectangular boss 9-1, connecting plate 9-2, connecting head one 10-1, connecting section 10-2, connecting head two 10-3. DETAILED DESCRIPTION

[0018] The application will be described in further detail below with reference to the accompanying drawings and specific embodiments.

[0019] The application mainly consists of Y-shaped crank, rotating shaft and open connecting rod. In order to ensure stable work in high-temperature gas environment, Y-shaped crank, rotating shaft and open connecting rod are all made of high-temperature alloy. The thermal expansion coefficient of the material of the rotating shaft is greater than that of the material of the Y-shaped crank. The crank is a "Y-shaped" structure with a certain thickness, a through hole is provided in the "V-shaped" angle, and a rectangular groove is provided at one side end face. The connecting rod is a flat plate structure with a certain thickness, eccentric holes are provided at both ends, so that the connecting rod has openings at both ends. The rotating shaft is a cylindrical structure as a whole, a rectangular boss is provided at one side end face, and the middle position is processed into a plate structure with a certain thickness. The size of the rectangular boss of the rotating shaft is slightly larger than that of the rectangular groove on the Y-shaped crank. Before being combined together, the Y-shaped crank is soaked in hot oil at a certain temperature, so that the Y-shaped crank is heated and expanded. The rotating shaft is wrapped in dry ice, so that the rotating shaft is pre-cooled and shrunk. The Y-shaped crank and the rotating shaft are assembled together and left to stand until the room temperature condition, with the change of temperature, the temperature of the Y-shaped crank decreases, the size of the rectangular groove becomes smaller, the temperature of the rotating shaft increases, and the size of the rectangular boss becomes larger, finally the boss and the groove are tightly pressed against each other, and the locking function is completed. The angle of the open connecting rod is adjusted, so that the opening at one end of the connecting rod is inserted into the middle position of the rotating shaft, and the angle is adjusted again, so that the direction of the opening of the connecting rod changes, and the assembly is completed. Within the rotation angle range of the baffle, the opening position of the connecting rod is always at a certain angle with the middle plate position of the rotating shaft, the self-locking function is completed, so that the connecting rod will not be separated from the rotating shaft.

[0020] As shown in Figure 1 , the gas switching mechanism mainly consists of electric cylinder 1, crank connecting rod mechanism 2, baffle 3, outer machine case 4, middle machine case 5, inner machine case 6, air inlet section 7 and other components. The outer machine case 4 and the middle machine case 5 constitute a reverse channel, and the middle machine case 5 and the inner machine case 6 constitute a forward channel. The electric cylinder 1 drives the baffle 3 to rotate around point A through the crank connecting rod mechanism 2, and completes the change of the flow direction of the gas, that is, adjusts the baffle 3 to make the gas flow into the forward channel or the reverse channel.

[0021] As shown in Figure 2 , Figure 3As shown, the reversing turbine low-flow-resistance detachable crank-connecting rod mechanism of this embodiment mainly consists of a Y-shaped crank 8, a rotating shaft 9, and an open connecting rod 10. The Y-shaped crank 8 and the open connecting rod 10 are connected together by the rotating shaft 9. The rotating shaft 9 is fixed relative to the Y-shaped crank 8, and the open connecting rod 10 can rotate around the rotating shaft 9.

[0022] like Figure 4 As shown, the Y-type crank 8 in this embodiment has a "Y"-shaped structure. Compared with a right-angled crank, the "Y"-shaped structure can minimize the resistance to the flow of combustion gases and avoid flow loss caused by the combustion gases impacting the crank vertically. Two through holes are opened on the main body structure, and a rectangular groove 8-1 is provided on one end face. The width of the groove 8-1 is a = 6mm.

[0023] like Figure 5 As shown, the open connecting rod 10 in this embodiment mainly consists of a connector 10-1, a connecting section 10-2, and a connector 2 10-3. An opening of length L is provided on the connector 10-1.

[0024] like Figure 6 , Figure 7 As shown, the rotating shaft 9 in this embodiment is a cylindrical structure, with a rectangular boss 9-1 on one end face. The width of the rectangular boss 9-1 is a = 6.02 mm. A connecting plate 9-2 with a thickness of L1 is machined in the middle position. The two sides of the connecting plate 9-2 are arc-shaped and can be matched with the inner hole on the connector 10-1.

[0025] To complete the assembly of the crank-connecting rod mechanism 2, the Y-type crank 8 is first immersed in hot oil at 200℃, causing the Y-type crank to expand due to heat, and the width of the rectangular groove 8-1 changes from the initial value of 6mm to 6.015mm.

[0026] Furthermore, the rotating shaft 9 is encased in dry ice, causing it to pre-cool and shrink, and the width of the rectangular boss 9-1 changes from the initial value of 6mm to 5.993mm.

[0027] Furthermore, a gap of 0.022mm is formed between the rectangular groove 8-1 and the rectangular boss 9-1, and the rotating shaft 9 is inserted into the Y-shaped crank 8, while the rectangular boss 9-1 is inserted into the rectangular groove 8-1.

[0028] Furthermore, the Y-type crank 8 and the shaft 9 are placed at room temperature. As the temperature changes, the temperature of the Y-type crank 8 decreases, the size of the rectangular groove 8-1 decreases, and the temperature of the shaft 9 increases, the size of the rectangular boss 9-1 increases. Finally, the boss and the groove are pressed together with each other, and the interference fit is 0.02mm, thus completing the locking function between the Y-type crank 8 and the shaft 9.

[0029] Further, using the part interference assembly avoids the use of threaded connections, reduces the application of bolts and nuts, reduces the cross-sectional area of the crank connecting rod mechanism 2 in the gas flow, and reduces the flow resistance of the gas.

[0030] Further, in order to prevent the failure of interference fit in high temperature environment, the thermal expansion coefficient of the material of the rotating shaft 9 should be greater than the thermal expansion coefficient of the material of the Y-shaped crank 8. Finally, the rotating shaft 9 uses GH3030 material, and the Y-shaped crank 8 uses GH4099 material.

[0031] As shown in Figure 8 At a certain angle, the relative position of the connecting plate 9-2 and the open connecting rod 10 is adjusted so that L open corresponds to L1 thick plate, so that the open connecting rod 10 can be inserted into the rotating shaft 9. Rotating a certain angle again can change the direction of the connecting rod opening and complete the assembly.

[0032] Further, in the working state of the switching mechanism, within the rotation angle range of the baffle 3, the opening position of the open connecting rod 10 is always at a certain angle with the middle plate position of the rotating shaft 9, so that the open connecting rod 10 will not be separated from the rotating shaft 9.

[0033] In summary, the present application discloses a low-flow-resistance detachable crank connecting rod mechanism applied to a reversing turbine, which mainly comprises a Y-shaped crank, a rotating shaft and an open connecting rod. The mechanism innovatively designs a rectangular boss on one side of the rotating shaft and a rectangular groove on the Y-shaped crank, and the rotating shaft and the Y-shaped crank are fixed together through interference fit, avoiding the use of traditional bolt and nut connection, improving the structural reliability, and reducing the area of the gas flow position blocking the gas, thereby reducing the flow resistance of the gas. On this basis, the middle position of the rotating shaft is provided with an arc-shaped thick plate structure at both ends, and the connecting rod is designed in an open form, so that at a certain angle, the open connecting rod can be inserted into the thick plate on the rotating shaft through the opening on the open connecting rod, completing the assembly of the crank connecting rod mechanism, and the open connecting rod can also be disassembled through the opening, but it cannot be disassembled within the working angle range.

[0034] The low-flow-resistance detachable crank connecting rod mechanism applied to the reversing turbine has the advantages of simple structure, high stability, small resistance to gas, and can complete the assembly and disassembly of the crank connecting rod without disassembling the rotating shaft.

Claims

1. A low flow resistance detachable crank and connecting rod mechanism applied to a reversing turbine, characterized in that: The Y-shaped crank connected with the electric cylinder output end of the gas switching mechanism, the rotating shaft connected with the Y-shaped crank, and the open connecting rod connected with the rotating shaft are provided with the rectangular boss on one side of the rotating shaft and the rectangular recess matched with the rectangular boss on the Y-shaped crank, so that the rotating shaft and the Y-shaped crank are connected through interference fit; the open connecting rod is composed of the connecting head one, the connecting section, and the connecting head two, and the opening with the length L is formed on the connecting head one, through which the rotating shaft is inserted to complete the assembly of the crank connecting rod mechanism, and through which the disassembly is completed; within the rotating angle range of the baffle, the opening position is always at an angle with the middle plate position of the rotating shaft to complete the self-locking function, so that the connecting rod cannot be separated from the rotating shaft; The rotating shaft is in the overall cylindrical structure, the rectangular boss is arranged on one side end face, the middle position of the rotating shaft is the connecting plate structure with the thickness L1, and the two sides of the middle plate of the rotating shaft are in the arc structure matched with the inner hole on the connecting head one; The opening size L on the open connecting rod is greater than the size L1 of the middle plate of the rotating shaft.

2. A low-drag, removable crank-and-rod mechanism for a reversing turbine according to claim 1, characterized in that: The thermal expansion coefficient of the rotating shaft material is greater than the thermal expansion coefficient of the Y-shaped crank material, and the interference state is always maintained under the high-temperature working condition.

3. A low-drag, removable crank-and-rod mechanism for a reversing turbine according to claim 1 or 2, characterized in that: The size of the rectangular boss of the rotating shaft is slightly greater than the size of the rectangular recess on the Y-shaped crank, and the interference connection is realized.

Images