A new type of small steam turbine oil motor feedback device

Abstract

The present invention belongs to the technical field of oil motor feedback devices, and is particularly a novel small steam turbine oil motor feedback device, comprising an oil cylinder and a connecting piece, a piston rod is arranged on the top of the oil cylinder, a fixed clamp is fixedly connected to the surface of the piston rod, a U-shaped groove is provided on the end face of the connecting piece, the piston rod is movably connected inside the U-shaped groove, through holes are provided on the opposite inner walls of the U-shaped groove, the same bolt is passed through the two through holes, one end of the bolt is threadedly connected to a first fastener, and a displacement sensor is provided on the side of the oil cylinder. The intermediate links are simplified by modifying the oil motor feedback device, the connecting piece is made into an integral steel plate and connected to the feedback rod through a return bend, and is fixed using a first fastener and a second fastener, which effectively prevents the occurrence of oil motor failures caused by loose parts and broken connecting plates, while simplifying the disassembly and assembly workload and saving production costs.

Description

Technical Field

[0001] The invention belongs to the technical field of oil motor feedback devices, and in particular relates to a novel small steam turbine oil motor feedback device. Background Art

[0002] In the speed control system of small steam turbines in thermal power plants, oil motors are usually used to control the steam distribution mechanism of small steam turbines. The control principle is as follows: the DCS host computer logic outputs a 4-20mA signal (corresponding to 3000-5334RPM) to the 505 controller after automatic calculation of water supply or operation by the operator. The 505 controller receives the frequency signal sent by the speed probe (the higher of the two speed signals is taken), and after conversion by the internal frequency / voltage converter, it is compared with the set value to generate a corresponding 4-20mA analog signal, which is output to the regulator in the local control box. The regulator compares the set value with one LVDT (the other LVDT is only used for the upper computer display) and feeds back the output signal to the DCS host computer. DV valve and DDV valve convert electrical signals into oil pressure signals to control the small oil motor, so the stability of the small steam turbine oil motor feedback device is very important. In the prior art, the piston rod is connected to the displacement sensor through a screw, and a bracket needs to be set on the piston rod. The bracket is generally a buckle, which is assembled on the piston rod by bolts, and one end of the adjusting screw is fixed to the connecting plate by a nut. Since the oil motor moves frequently during the operation of the unit, and there are many assembled parts between the piston rod and the feedback rod, the parts are easy to loosen under the influence of the vibration of the piston rod, and the root of the feedback rod is thin and easy to break. If the operating personnel do not find it in time, it is easy to cause the oil motor to lose control or even cause the small steam turbine to trip. Summary of the invention

[0003] 1. Technical issues to be resolved

[0004] In view of the deficiencies in the prior art, the present invention provides a novel small steam turbine oil motor feedback device, which has the advantages of effectively preventing the occurrence of oil motor failures caused by loose parts and broken connecting plates, and solves the problems of too many assembled parts between the oil motor piston rod and the feedback rod of the displacement sensor, which leads to loose parts and the feedback rod root is thin and easy to break.

[0005] (II) Technical solution

[0006] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a novel small steam turbine oil motor feedback device, comprising a cylinder and a connecting piece, a piston rod is arranged on the top of the cylinder, a fixed clamp is fixedly connected to the surface of the piston rod, a U-shaped groove is provided on the end face of the connecting piece, the piston rod is movably connected to the inside of the U-shaped groove, through holes are provided on the opposite inner walls of the U-shaped groove, the same bolt is passed through the inside of the two through holes, one end of the bolt is threadedly connected to a first fastener, a displacement sensor is arranged on the side of the cylinder, a feedback rod is arranged on the top of the displacement sensor, one end of the feedback rod is provided with an external thread, a circular hole is provided on the top of the connecting piece, the feedback rod is movably connected to the inside of the circular hole, a second fastener is arranged on the feedback rod, the number of the second fasteners is two, and the surfaces of the two second fasteners are both overlapped with the surface of the connecting piece.

[0007] By adopting the above scheme, the intermediate links are simplified by modifying the feedback device of the oil motor. The connecting piece is made into an integral steel plate and connected to the feedback rod through a return bend. It is fixed with the first fastener and the second fastener, which effectively prevents the occurrence of oil motor failure caused by loose parts and broken connecting plates. At the same time, the disassembly and assembly workload is simplified, saving production costs.

[0008] Preferably, the second fastener comprises a threaded cap, a groove is formed at the bottom of the threaded cap, a spring is fixedly connected to the top of the inner wall of the groove, and shock-proof gaskets are overlapped at the bottom ends of the threaded cap and the spring.

[0009] Preferably, the threaded cap is threadedly connected to the surface of the feedback rod via an external thread, and the bottom of the shock-proof gasket overlaps the surface of the connecting piece.

[0010] Preferably, the first fastener and the second fastener have the same internal structure.

[0011] By adopting the above solution, the threaded cap is limited under the elastic force of the spring, and the threaded cap is prevented from rotating when the connecting piece moves. By providing a shock-proof gasket, the problem of loosening of the threaded cap is effectively solved.

[0012] Preferably, the connecting piece is made of an integral steel plate, and one end of the connecting piece is provided with a return bend.

[0013] By adopting the above scheme, the connecting piece and the piston rod are fixed by the first fastener. The connecting piece is a whole steel plate without a welding joint in the middle, which improves the strength of the overall connecting piece and solves the problem of breakage of the original connecting piece. The intermediate links are simplified by the one-piece plate design, and the occurrence of oil motor failure caused by loose parts is reduced. In addition, by setting a return bend, the problem of scratching between the connecting piece and the oil cylinder in the fully open position is solved.

[0014] (III) Beneficial effects

[0015] Compared with the prior art, the present invention provides a novel small steam turbine oil motor feedback device, which has the following beneficial effects:

[0016] The novel small steam turbine oil motor feedback device simplifies the intermediate links by setting a connecting piece, a first fastener and a second fastener, and transforming the oil motor feedback device. The connecting piece is made into an integral steel plate and is connected to the feedback rod through a return bend, and is fixed with the first fastener and the second fastener, which effectively prevents the occurrence of oil motor failures caused by loose parts and broken connecting plates, and simplifies the disassembly and assembly workload, saving production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic structural diagram of a front cross-section of the present invention;

[0018] Figure 2 For the present invention Figure 1 The enlarged structural diagram of the middle A part;

[0019] Figure 3 It is a structural schematic diagram of an enlarged cross section of the second fastener in the present invention;

[0020] In the figure:

[0021] 1. Oil cylinder; 2. Piston rod; 3. Fixed clamp; 4. Connector; 5. U-shaped groove; 6. Bolt; 7. First fastener; 8. Displacement sensor; 9. Feedback rod; 10. External thread; 11. Round hole; 12. Second fastener; 121. Threaded cap; 122. Groove; 123. Spring; 124. Shockproof gasket. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] Embodiment 1

[0024] A novel small steam turbine oil motor feedback device comprises an oil cylinder 1 and a connecting member 4, wherein a piston rod 2 is arranged on the top of the oil cylinder 1, a fixed clamping plate 3 is fixedly connected to the surface of the piston rod 2, a U-shaped groove 5 is provided on the end surface of the connecting member 4, the piston rod 2 is movably connected to the inside of the U-shaped groove 5, through holes are provided on the opposite inner walls of the U-shaped groove 5, the same bolt 6 is penetrated inside the two through holes, a first fastener 7 is threadedly connected to one end of the bolt 6, a displacement sensor 8 is arranged on the side of the oil cylinder 1, a feedback rod 9 is arranged on the top of the displacement sensor 8, an external thread 10 is provided at one end of the feedback rod 9, a circular hole 11 is provided on the top of the connecting member 4, the feedback rod 9 is movably connected to the inside of the circular hole 11, a second fastener 12 is arranged on the feedback rod 9, the number of the second fasteners 12 is two, and the surfaces of the two second fasteners 12 are both overlapped with the surface of the connecting member 4.

[0025] See also Figure 1-3 By modifying the feedback device of the oil motor, the intermediate links are simplified. The connecting piece 4 is made into an integral steel plate and connected to the feedback rod 9 through a return bend. It is fixed with the first fastener 7 and the second fastener 12, which effectively prevents the occurrence of oil motor failures caused by loose parts and broken connecting plates. At the same time, the disassembly and assembly workload is simplified, saving production costs.

[0026] Embodiment 2

[0027] The second fastener 12 includes a threaded cap 121, a groove 122 is formed at the bottom of the threaded cap 121, a spring 123 is fixedly connected to the top of the inner wall of the groove 122, and a shock-proof gasket 124 is overlapped at the bottom ends of the threaded cap 121 and the spring 123. The threaded cap 121 is threadedly connected to the surface of the feedback rod 9 through an external thread 10, and the bottom of the shock-proof gasket 124 overlaps the surface of the connecting member 4. The first fastener 7 has the same internal structure as the second fastener 12.

[0028] See also Figure 1-3 Under the elastic force of the spring 123, the threaded cap 121 is limited, and when the connecting member 4 moves, the threaded cap 121 is prevented from rotating. By setting the shockproof gasket 124, the problem of loosening of the threaded cap 121 is effectively solved.

[0029] Embodiment 3

[0030] The connecting member 4 is made of an integral steel plate, and one end of the connecting member 4 is provided with a return bend.

[0031] See also Figure 1-3The connecting piece 4 and the piston rod 2 are fixed by a first fastener 7. The connecting piece 4 is a whole steel plate without a welding joint in the middle, which improves the strength of the overall connecting piece 4 and solves the problem of the original connecting piece 4 breaking. The one-piece plate design simplifies the intermediate links and reduces the occurrence of oil motor failures caused by loose parts. In addition, by setting a return bend, the problem of the connecting piece 4 and the oil cylinder 1 scratching in the fully open position is solved.

[0032] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A new type of small steam turbine oil motor feedback device, characterized by: The invention comprises an oil cylinder (1) and a connecting piece (4), wherein a piston rod (2) is arranged on the top of the oil cylinder (1), a fixed clamping plate (3) is fixedly connected to the surface of the piston rod (2), a U-shaped groove (5) is provided on the end surface of the connecting piece (4), the piston rod (2) is movably connected to the inside of the U-shaped groove (5), through holes are provided on the opposite inner walls of the U-shaped groove (5), a same bolt (6) is passed through the inside of the two through holes, one end of the bolt (6) is threadedly connected to a first fastener (7), a displacement sensor (8) is arranged on the side of the oil cylinder (1), a feedback rod (9) is arranged on the top of the displacement sensor (8), one end of the feedback rod (9) is provided with an external thread (10), and the top of the connecting piece (4) is provided with a plurality of external threads (11). A circular hole (11) is provided, the feedback rod (9) is movably connected inside the circular hole (11), a second fastener (12) is provided on the feedback rod (9), the number of the second fasteners (12) is two, the surfaces of the two second fasteners (12) are overlapped with the surface of the connecting member (4); the second fastener (12) includes a threaded cap (121), the bottom of the threaded cap (121) is provided with a groove (122), the top of the inner wall of the groove (122) is fixedly connected with a spring (123), and the bottom ends of the threaded cap (121) and the spring (123) are overlapped with a shock-proof gasket (124); the connecting member (4) is made of an integral steel plate, and one end of the connecting member (4) is provided with a return bend.

2. According to claim 1, a novel small steam turbine oil motor feedback device is characterized in that: The threaded cap (121) is threadedly connected to the surface of the feedback rod (9) via an external thread (10), and the bottom of the shockproof gasket (124) overlaps the surface of the connecting piece (4).

3. According to claim 1, a novel small steam turbine oil motor feedback device is characterized in that: The first fastener (7) and the second fastener (12) have the same internal structure.

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