Rotating speed alarm device for air turbine starter

Abstract

The invention belongs to the technical field of rotating speed alarm devices, and relates to a rotating speed alarm device for an air turbine starter, which comprises a centrifugal push rod assembly, a cover plate, a bearing, a sealing assembly, a sealing ring, a cover, a microswitch, an electric wire, an electric socket and a shell, the centrifugal push rod assembly is circumferentially fixed in the shell through a bearing and is axially fastened with an inner ring of the bearing through locking of a nut and a locking plate, and the cover plate is fixed on the shell and axially fixes an outer ring of the bearing; the sealing assembly is fastened on the shell and installed below the centrifugal push rod assembly, the microswitch is fixed on the shell and installed below the sealing assembly, and a button of the microswitch is within the stroke range of an ejector rod of the sealing assembly. According to the invention, by adding an over-rotation alarm measure, the problem of accidental over-rotation-speed operation can be found and processed in time, so that the technical problems existing in the prior art can be solved.

Description

Technical Field

[0001] The invention belongs to the technical field of rotation speed alarm devices and relates to a rotation speed alarm device for an air turbine starter. Background Art

[0002] The air turbine starter is an important accessory of the engine starting system. Its working principle is to withstand the impact of high-temperature and high-pressure gas source, extract internal energy and convert it into mechanical shaft power, and drive the engine high-pressure rotor to a predetermined speed through the starter output shaft. It is mainly used for ground starting, cold running, false start and air auxiliary starting of the engine. Due to its working principle, its working characteristics are large impact torque, high power density and high operating speed. However, due to the lightweight design requirements of aviation products, the design strength margin of parts is limited, and the tolerance for overspeed use is poor. Faults such as turbine disc rupture, turbine blade breakage, and bearing 002 damage induced by accidental overspeed operation can pose a serious threat to flight safety.

[0003] To solve the problem of accidental overspeed operation, the general solution is to increase the design margin, such as replacing the stainless steel turbine with a titanium alloy turbine to increase the turbine specific strength, increasing the thickness of the turbine disk, and selecting bearings with larger size and weight, etc. However, this over-design approach brings huge waste. Summary of the invention

[0004] Purpose of the invention: The present invention provides a speed alarm device for an air turbine starter, which can timely discover and deal with unexpected overspeed operation problems by adding overspeed alarm measures, so as to solve the technical problems existing in the prior art.

[0005] The technical solution adopted by the present invention is as follows:

[0006] A speed alarm device for an air turbine starter comprises a centrifugal push rod assembly 100, a cover plate 001, a bearing 002, a nut and a locking plate 003, a sealing assembly 200, a sealing ring 004, a cover 006, a micro switch 007, an electric wire 008, an electric socket 009 and a housing 010; the centrifugal push rod assembly 100 is circumferentially fixed in the housing 010 by the bearing 002, and is axially locked and fastened to the inner ring of the bearing 002 by the nut and the locking plate 003; the cover plate 001 is fixed on the housing 010 and axially fixes the outer ring of the bearing 002; the sealing assembly 200 is fastened on the housing 010 and installed below the centrifugal push rod assembly 100; the micro switch 007 is fixed on the housing 010 and installed below the sealing assembly 200; the button of the micro switch 007 is within the travel range of the push rod 208 of the sealing assembly 200; the electric socket 009 is connected to the micro switch 007.

[0007] Furthermore, the cover plate 001 is fixed to the housing 010 by screw six, axially fixing the outer ring of the bearing 002; the sealing assembly 200 is fastened to the housing 010 by screw two and installed below the centrifugal push rod assembly 100; the micro switch 007 is fixed to the housing 010 by screw three.

[0008] Further, the electrical socket 009 is connected to the micro switch 007 via the electrical wire 008 .

[0009] Furthermore, the centrifugal push rod assembly 100 includes an elastic retaining ring 101, a gear 102, a centrifugal assembly 103, a push rod 104, an adjusting gasket 105, and a spring 106. The centrifugal assembly 103 is installed in the gear 102, and the top end is clamped by the elastic retaining ring 101; the push rod 104 is installed at the lower end of the centrifugal assembly 103 and fits with the centrifugal block 111; a spring 106 is installed at the bottom of the push rod 104, and an adjusting gasket 105 is installed between the spring 106 and the push rod 104 according to the elastic force requirements.

[0010] Furthermore, the centrifugal assembly 103 includes two centrifugal blocks 111, four spacers 112, two pins 113 and a centrifugal bracket 114. The centrifugal bracket 114 is a cylindrical hollow structure with an installation groove arranged inside. Installation pin holes are arranged on both sides of the installation groove. The centrifugal block 111 is installed on the pin 113, and the center of gravity of the centrifugal block 111 is located above the pin hole. Under the action of centrifugal force, the centrifugal block 111 can flip around the pin 113 within a certain angle range. A spacer 112 is installed on the left and right sides of each centrifugal block 111. Both ends of the pin 113 are respectively installed in the pin holes corresponding to the positions on both sides of the centrifugal bracket 114, and the two ends of the pin 113 are gap-matched with the pin holes corresponding to the positions on both sides of the centrifugal bracket 114. The centrifugal block 111 and the spacer 112 are gap-matched with the pin 113.

[0011] Furthermore, four arc grooves are machined axially inside the gear 102 to cooperate with the pin 113 of the centrifugal assembly 103 to achieve circumferential positioning of the centrifugal assembly 103. An elastic retaining ring 101 groove is designed on the top of the gear 102 to cooperate with the elastic retaining ring 101 to achieve axial positioning of the centrifugal assembly 103. The lower part of the gear 102 is a hollow shaft structure, and a small hole is opened at the bottom of the shaft to allow the push rod 104 to extend and retract through. The outer surface of the hollow shaft is machined with threads that cooperate with the locking nut threads to fix the centrifugal assembly 103 on the bearing 002.

[0012] Furthermore, the centrifugal block 111 is provided with a pin hole, and a sharp corner is extended from the side, and the sharp corner is used to push the push rod 104, and the center of gravity of the centrifugal block 111 is located above the pin hole; two centrifugal blocks 111 are used in pairs, and the weight difference is not greater than 0.1g.

[0013] Furthermore, the sealing assembly 200 includes a screw 201, an outer washer 202, a leather cup 203, an inner washer 204, a sealing bracket 205, a sealing ring 206, a spring 207, and a push rod 208; the sealing bracket 205 buckles the outer washer 202 by extrusion deformation, and the outer washer 202 presses the outer ring of the leather cup 203 into the sealing bracket 205, and the screw 201 cooperates with the push rod 208 through a thread, and the screw 201 and the push rod 208 are connected. An inner gasket 204 and an inner ring of the leather cup 203 are installed between them, and screw four 201 is tightened to fasten the inner gasket 204 and the inner ring of the leather cup 203. When the push rod 104 is extended, screw four 201 is pressed to drive the leather cup 203 and the push rod 208 to output downward displacement. Spring two 207 is installed under the inner gasket 204. When the push rod 104 is retracted, screw four 201 and the push rod 208 are reset under the action of spring two 207, and a sealing ring 206 is installed on the outside of the sealing bracket 205.

[0014] Furthermore, a folding transition area is provided between the straight inner and outer diameter fitting areas of the leather cup 203 so that the leather cup 203 can be stretched and deformed.

[0015] Beneficial effects:

[0016] 1. The centrifugal block 111 in the centrifugal assembly 103 is designed so that the center of gravity of the centrifugal block 111 is located above the pin hole. When rotating at high speed, the point of action of the centrifugal force is located at the center of gravity, that is, above the pin hole, generating a rotational torque, causing the centrifugal block 111 to flip around along the pin 113. The sharp corner structure at the bottom of the centrifugal block 111 causes the sharp corner to press the push rod 104 when the centrifugal block 111 flips, outputting an axial displacement.

[0017] 2. The centrifugal push rod assembly 100 controls the turning speed of the centrifugal block 111 through the elastic force of the spring 106 and the centrifugal force generated by the high-speed rotation of the centrifugal block 111. In the low-speed stage, the centrifugal force of the centrifugal block 111 is small, and the elastic force of the spring 106 keeps the push rod 104 in place; when the speed reaches the alarm speed, the centrifugal force of the centrifugal block 111 is sufficient to overcome the elastic force of the spring 106, and the sharp corner presses the push rod 104 to output axial displacement. The adjustment gasket 105 plays the role of adjusting the elastic force of the spring 106, and then plays the role of controlling the alarm speed.

[0018] 3. The inner and outer diameter fitting areas of the leather cup 203 in the sealing assembly 200 are tightly fitted with the mating parts, ensuring the oil sealing between the inner and outer sides of the sealing assembly 200. At the same time, the folded transition area of ​​the leather cup 203 allows the reciprocating motion of the push rod 104. When the parts such as the gear 102 and the bearing 002 rotate at high speed, they must be lubricated with grease, but the wire 008 and the electrical socket 009 cannot be immersed in oil, and the sealing assembly 200 is used to isolate the two parts.

[0019] 4. The hollow structure inside the gear 102 allows the centrifugal assembly 103, the push rod 104 and other parts to be embedded therein, and the structure is compact; the gear 102 can contact any gear 102 transmission system, and has strong adaptability.

[0020] 5. The device is connected to the mechanical transmission system through the gear 102. When the speed of the gear 102 exceeds the set value, the centrifugal block 111 fixed on the gear 102 overcomes the elastic force of the spring 106 under the action of centrifugal force and flips. After flipping, the sharp corner of the centrifugal block 111 presses down the push rod 104, and the push rod 104 presses down the push rod 208 of the sealing assembly 200, and the push rod 208 presses the micro switch 007 button, the circuit is closed, and an electrical signal is sent to the control system to indicate that the speed is too high. The setting of the alarm speed can be controlled by adjusting the spring 106 elastic force by adjusting the gasket 105. The function of the sealing assembly 200 is to isolate the lubricating oil cavity and the circuit cavity while transmitting the stroke of the push rod 104. For example, the normal maximum turbine operating speed of a certain type of air turbine starter is between 33237 and 35450 r / min, and the alarm speed of the speed alarm device is set to between 41000 and 43000 r / min. The speed alarm device of the present invention can effectively indicate the speed over-high fault.

[0021] 6. The present invention has high reliability in electromagnetic environment and high temperature environment.

[0022] 7. The production cost of the present invention is low and is suitable for mass production. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram of a rotation speed alarm device according to an embodiment of the present invention;

[0024] Figure 2 A schematic diagram of a centrifugal push rod assembly 100 according to an embodiment of the present invention;

[0025] Figure 3 A cross-sectional view of a centrifugal assembly 103 according to an embodiment of the present invention;

[0026] Figure 4 A top view of a centrifugal assembly 103 according to an embodiment of the present invention;

[0027] Figure 5 An exploded view of a centrifugal assembly 103 according to an embodiment of the present invention;

[0028] Figure 6 A schematic diagram of a sealing assembly 200 according to an embodiment of the present invention;

[0029] Figure 7 is a cross-sectional view of a gear 102 according to an embodiment of the present invention;

[0030] Figure 8 A top view of a gear 102 according to an embodiment of the present invention;

[0031] Fig. 9 Schematic diagram of a leather cup 203 according to an embodiment of the present invention. DETAILED DESCRIPTION

[0032] See also Figure 1 As shown, the present invention provides an embodiment of a speed alarm device for an air turbine starter, comprising a centrifugal push rod assembly 100, a cover plate 001, a bearing 002, a nut and a locking plate 003, a sealing assembly 200, a sealing ring 004, a screw 1 005, a cover 006, a micro switch 007, a wire 008 and an electrical socket 009, and a housing 010. The centrifugal push rod assembly 100 is circumferentially fixed in the housing 010 through the bearing 002, and is axially locked and fastened to the inner ring of the bearing 002 through the nut and the locking plate 003. The cover plate 001 is fixed to the housing 010 through screw 6, and the outer ring of the bearing 002 is axially fixed. The sealing assembly 200 is fastened to the housing 010 through screw 2 and is installed below the centrifugal push rod assembly 100. The micro switch 007 is fixed to the housing 010 through screw 3 and is installed below the sealing assembly 200, and the button is within the travel range of the push rod 208 of the sealing assembly 200. The electrical socket 009 is connected to the micro switch 007 through the wire 008. The device can be connected to the gear 102 transmission system. If the speed exceeds the alarm speed, under the action of centrifugal force, the centrifugal block 111 in the centrifugal push rod assembly 100 flips and pushes the push rod 104, touches the top rod 208 of the sealing assembly 200, presses the button of the micro switch 007, and the circuit is closed to send out an alarm signal.

[0033] In this embodiment, the centrifugal push rod assembly 100 is circumferentially fixed in the housing 010 by the bearing 002, and axially locked and fastened to the inner ring of the bearing 002 by the nut and the locking plate 003. The cover plate 001 is fixed on the housing 010 to axially fix the outer ring of the bearing 002; the sealing assembly 200 is fastened on the housing 010 and installed below the centrifugal push rod assembly 100; the micro switch 007 is fixed on the housing 010 and installed below the sealing assembly 200; the button of the micro switch 007 is within the travel range of the push rod 208 of the sealing assembly 200; the electrical socket 009 is connected to the micro switch 007.

[0034] In this embodiment, the cover plate 001 is fixed to the housing 010 by screw six, axially fixing the outer ring of the bearing 002; the sealing assembly 200 is fastened to the housing 010 by screw two and installed below the centrifugal push rod assembly 100; the micro switch 007 is fixed to the housing 010 by screw three.

[0035] In this embodiment, the electrical socket 009 is connected to the micro switch 007 via the wire 008 .

[0036] In this embodiment, the centrifugal push rod assembly 100 includes an elastic retaining ring 101, a gear 102, a centrifugal assembly 103, a push rod 104, an adjusting gasket 105, and a spring 106. The centrifugal assembly 103 is installed in the gear 102, and the top end is clamped by the elastic retaining ring 101; the push rod 104 is installed at the lower end of the centrifugal assembly 103 and fits with the centrifugal block 111; a spring 106 is installed at the bottom of the push rod 104, and an adjusting gasket 105 is installed between the spring 106 and the push rod 104 according to the elastic force requirements.

[0037] In this embodiment, the centrifugal assembly 103 includes two centrifugal blocks 111, four spacers 112, two pins 113 and a centrifugal bracket 114. The centrifugal bracket 114 is a cylindrical hollow structure with an installation groove arranged inside. Installation pin holes are arranged on both sides of the installation groove. The centrifugal block 111 is installed on the pin 113, and the center of gravity of the centrifugal block 111 is located above the pin hole. Under the action of centrifugal force, the centrifugal block 111 can flip around the pin 113 within a certain angle range. A spacer 112 is installed on the left and right sides of each centrifugal block 111. The two ends of the pin 113 are respectively installed in the pin holes corresponding to the positions on both sides of the centrifugal bracket 114, and the two ends of the pin 113 are gap-matched with the pin holes corresponding to the positions on both sides of the centrifugal bracket 114. The centrifugal block 111 and the spacer 112 are gap-matched with the pin 113.

[0038] In this embodiment, four arc grooves are machined axially inside the gear 102 to cooperate with the pin 113 of the centrifugal assembly 103 to achieve circumferential positioning of the centrifugal assembly 103. An elastic retaining ring 101 groove is designed on the top of the gear 102 to cooperate with the elastic retaining ring 101 to achieve axial positioning of the centrifugal assembly 103. The lower part of the gear 102 is a hollow shaft structure, and a small hole is opened at the bottom of the shaft to allow the push rod 104 to extend and retract through. The outer surface of the hollow shaft is machined with threads that cooperate with the locking nut threads to fix the centrifugal assembly 103 on the bearing 002.

[0039] In this embodiment, the centrifugal block 111 is provided with a pin hole and a sharp corner extending from the side, the sharp corner is used to push the push rod 104, and the center of gravity of the centrifugal block 111 is located above the pin hole; two centrifugal blocks 111 are used in pairs, and the weight difference is no more than 0.1g.

[0040] In this embodiment, the sealing assembly 200 includes a screw 201, an outer washer 202, a leather cup 203, an inner washer 204, a sealing bracket 205, a sealing ring 206, a spring 207, and a push rod 208; the sealing bracket 205 buckles the outer washer 202 by extrusion deformation, and the outer washer 202 presses the outer ring of the leather cup 203 into the sealing bracket 205, the screw 201 cooperates with the push rod 208 through a thread, and the inner washer 204 and the inner ring of the leather cup 203 are installed between the screw 201 and the push rod 208, and the screw Tighten screw four 201 to fasten the inner washer 204 and the inner ring of the leather cup 203. When the push rod 104 is extended, the screw four 201 is pressed to drive the leather cup 203 and the push rod 208 to output downward displacement. Spring two 207 is installed under the inner washer 204. When the push rod 104 is retracted, the screw four 201 and the push rod 208 are reset under the action of spring two 207. The sealing ring 206 is installed on the outside of the sealing bracket 205. Among them, the leather cup 203 is provided with a folding transition area between the straight inner and outer diameter fitting areas to facilitate the expansion and contraction of the leather cup 203.

[0041] The working principle of the alarm device of the present invention is as follows: the device is connected to the mechanical transmission system through the gear 102. When the speed of the gear 102 exceeds the set value, the centrifugal block 111 fixed on the gear 102 overcomes the elastic force of the spring 106 under the action of the centrifugal force and flips over. After flipping, the sharp corner of the centrifugal block 111 presses down the push rod 104, and the push rod 104 presses down the push rod 208 of the sealing assembly 200, and the push rod 208 presses the button of the micro switch 007, the circuit is closed, and an electrical signal is sent to the control system to indicate that the speed is too high. The setting of the alarm speed can be controlled by adjusting the elastic force of the spring 106 by adjusting the gasket 105. The function of the sealing assembly 200 is to isolate the lubricating oil cavity and the circuit cavity while transmitting the stroke of the push rod 104.

[0042] The normal maximum turbine operating speed of a certain type of air turbine starter is between 33237 and 35450 r / min, and the alarm speed of the speed alarm device is set to between 41000 and 43000 r / min. The speed alarm device of the present invention can effectively indicate the over-high speed fault.

[0043] The above results show that the device of the present invention has achieved the expected goal and is practicable.

[0044] Based on the above verification, it can be known that the air turbine starter speed alarm device provided by this embodiment has a simple structure, is easy to manufacture, is easy to integrate into the existing air turbine starter, and can effectively indicate the problem of excessive speed. At the same time, it has little effect on the normal operation of the air turbine starter.

[0045] In addition, there are many specific implementation methods and approaches of the present invention, and the above is only a preferred implementation of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A speed alarm device for an air turbine starter, characterized in that: The invention comprises a centrifugal push rod assembly (100), a cover plate (001), a bearing (002), a sealing assembly (200), a sealing ring (004), a cover (006), a micro switch (007), an electric wire (008), an electric socket (009), and a housing (010); the centrifugal push rod assembly (100) is circumferentially fixed in the housing (010) by the bearing (002), and is axially locked and fastened to the inner ring of the bearing (002) by a nut and a locking plate (003); the cover plate (001) The micro switch (007) is fixed on the housing (010) and axially fixes the outer ring of the bearing (002); the sealing assembly (200) is fastened to the housing (010) and installed below the centrifugal push rod assembly (100); the micro switch (007) is fixed on the housing (010) and installed below the sealing assembly (200); the button of the micro switch (007) is within the travel range of the push rod (208) of the sealing assembly (200); and the electrical socket (009) is connected to the micro switch (007).

2. The speed alarm device for an air turbine starter according to claim 1, characterized in that: The cover plate (001) is fixed to the housing (010) by screw six, axially fixing the outer ring of the bearing (002); the sealing assembly (200) is fastened to the housing (010) by screw two, and is installed below the centrifugal push rod assembly (100); and the micro switch (007) is fixed to the housing (010) by screw three.

3. The speed alarm device for an air turbine starter according to claim 1, characterized in that: The electrical socket (009) is connected to the micro switch (007) via an electric wire (008).

4. The speed alarm device for an air turbine starter according to claim 1, characterized in that: The centrifugal push rod assembly (100) comprises an elastic retaining ring (101), a gear (102), a centrifugal assembly (103), a push rod (104), an adjustment gasket (105), and a spring (106). The centrifugal assembly (103) is installed in the gear (102), and the top end is clamped by the elastic retaining ring (101); the push rod (104) is installed at the lower end of the centrifugal assembly (103) and fits with the centrifugal block (111); the spring (106) is installed at the bottom of the push rod (104), and the adjustment gasket (105) is installed between the spring (106) and the push rod (104) according to the elastic force requirement.

5. The speed alarm device for an air turbine starter according to claim 4, characterized in that: The centrifugal assembly (103) comprises two centrifugal blocks (111), four spacers (112), two pins (113) and a centrifugal support (114). The centrifugal support (114) is a cylindrical hollow structure, wherein a mounting groove is arranged inside the centrifugal support, and mounting pin holes are arranged on both sides of the mounting groove. The centrifugal block (111) is mounted on the pin (113), and the center of gravity of the centrifugal block (111) is located above the pin hole. Under the action of centrifugal force, the centrifugal block (111) can flip around the pin (113) within a certain angle range. A spacer (112) is respectively installed on the left and right sides of each centrifugal block (111), and the two ends of the pin (113) are respectively installed in the pin holes corresponding to the positions on both sides of the centrifugal support (114), and the two ends of the pin (113) are gap-matched with the pin holes corresponding to the positions on both sides of the centrifugal support (114), and the centrifugal block (111) and the spacer (112) are gap-matched with the pin (113).

6. The speed alarm device for an air turbine starter according to claim 5, characterized in that: Four arc grooves are machined in the axial direction inside the gear (102) for cooperating with the pin (113) of the centrifugal assembly (103) to realize the circumferential positioning of the centrifugal assembly (103). An elastic retaining ring (101) groove is designed at the top of the gear (102) for cooperating with the elastic retaining ring (101) to realize the axial positioning of the centrifugal assembly (103). The lower part of the gear (102) is a hollow shaft structure, and a small hole is opened at the bottom of the shaft to facilitate the push rod (104) to extend and pass through. The outer surface of the hollow shaft is machined with threads, which cooperate with the threads of the locking nut to fix the centrifugal assembly (103) on the bearing (002).

7. The speed alarm device for an air turbine starter according to claim 5, characterized in that: The centrifugal block (111) is provided with a pin hole, and a sharp corner is extended from the side, and the sharp corner is used to push the push rod (104). The center of gravity of the centrifugal block (111) is located above the pin hole; two centrifugal blocks (111) are used in pairs, and the weight difference is not greater than 0.1g.

8. The speed alarm device for an air turbine starter according to claim 4, characterized in that: The sealing assembly (200) comprises screw four (201), an outer washer (202), a leather cup (203), an inner washer (204), a sealing bracket (205), a sealing ring (206), a second spring (207), and a push rod (208); the sealing bracket (205) buckles the outer washer (202) by extrusion deformation, and the outer washer (202) presses the outer ring of the leather cup (203) into the sealing bracket (205); the screw four (201) cooperates with the push rod (208) through a thread, and a seal is formed between the screw four (201) and the push rod (208). An inner washer (204) and an inner ring of a leather cup (203) are installed between the inner washer (204) and the inner ring of the leather cup (203), and screw four (201) is tightened to tighten the inner washer (204) and the inner ring of the leather cup (203). When the push rod (104) is extended, screw four (201) is pressed to drive the leather cup (203) and the push rod (208) to output displacement downward. Spring two (207) is installed under the inner washer (204). When the push rod (104) is retracted, screw four (201) and the push rod (208) are reset under the action of spring two (207), and a sealing ring (206) is installed on the outside of the sealing bracket (205).

9. The speed alarm device for an air turbine starter according to claim 8, characterized in that: The leather cup (203) is provided with a folding transition area between the straight inner and outer diameter fitting areas so that the leather cup (203) can be stretched and deformed.

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