A differential pressure precision adjustment device for a propeller governor

Abstract

The present invention discloses a differential pressure precision regulating device for a propeller governor. There are left and right annular oil chambers between the right housing and the governor housing. The right housing is provided with a communicating oil hole, left and middle through oil holes, and a right oil return hole; Spring I is sleeved on the left and right spring seats; The left end of the secondary pressure regulating valve abuts against the right spring seat, and the right end abuts against the spool valve. There are annular oil chambers I, II, and III between the valve sleeve and the right housing; There are left and right annular cavities between the valve core and the valve sleeve. The valve sleeve wall is provided with left and right oil inlet holes and an oil return hole. A Spring II is sleeved on the valve core in the right annular cavity; The left oil inlet hole communicates the left annular cavity and the annular oil chamber I, the right oil inlet hole communicates the annular oil chamber II, and the oil return hole communicates the annular oil chamber III; The left through oil hole communicates the left annular oil chamber and the annular oil chamber I, the left annular oil chamber communicates with the large torque oil circuit, the middle through oil hole communicates the right annular oil chamber and the annular oil chamber III, and the right oil return hole communicates the right annular oil chamber; The right annular oil chamber communicates with the oil inlet of the gear pump; The spool valve seals the right oil return hole. The present invention has precise and rapid control over the propeller speed and high reliability.

Description

Technical Field

[0001] The present invention relates to a differential pressure precision regulating device for a propeller governor. Background Art

[0002] The regulation of the propeller speed depends on the change of the pressure in the coarse pitch oil circuit. The constant pitch oil pressure serves as the source of the pressure oil in the coarse pitch oil circuit. The precise control of the pressure in the constant pitch oil circuit, with rapid changes, can better control the speed of the propeller, which is crucial for maintaining the balanced speed of the propeller and meeting the matching requirements such as the acceleration and deceleration of the speed.

[0003] At present, the differential pressure regulating devices for propeller governors used in China are all constant pressure regulating mechanisms relying on springs, with only one-stage pressure regulation. When the propeller is normal, there is no problem in maintaining the constant pressure difference between the constant pitch oil pressure and the coarse pitch oil pressure by this one-stage pressure regulating mechanism. However, when other regulations of the propeller have problems or the pitch change of the propeller gets stuck, the coarse pitch oil pressure rises sharply. The corresponding speed of this one-stage pressure regulating mechanism is slow and the regulation accuracy is low. It is very difficult to maintain the constant pressure difference between the constant pitch oil pressure and the coarse pitch oil pressure only by this one-stage pressure regulating structure, resulting in the abnormal operation of the propeller and flight failures. Also, when the propeller is feathered, a very high oil pressure is required, such as 6 MPa. Since the oil discharge point of the high-pressure oil chamber of the one-stage pressure regulating mechanism is very low, such as 4 MPa, the high-pressure oil quickly discharges after entering this one-stage pressure regulating mechanism, reducing the oil pressure of the system, lengthening the feathering time of the propeller, and even causing feathering obstacles, leading to accidents. Summary of the Invention

[0004] The object of the present invention is to solve the above problems existing in the prior art, and provide a differential pressure precision regulating device for a propeller governor, which can not only maintain the constant pressure difference between the constant pitch oil pressure and the coarse pitch oil pressure when the propeller is normal, but also timely and accurately regulate to maintain the constant pressure difference between the constant pitch oil pressure and the coarse pitch oil pressure when the coarse pitch oil pressure rises sharply, and can also increase the feathering pressure of the propeller and reduce the feathering time; it can precisely and rapidly control the propeller speed with high reliability.

[0005] To achieve the above-mentioned purpose, the technical solution of the present invention is: a propeller speed governor differential pressure precision regulating device, which includes a left housing, a spring left seat, a spring I, a right housing, a spring right seat, a secondary pressure regulating valve, a sliding valve and a sliding valve shifting member; the left half of the inner hole of the right housing is the mounting hole of the spring right seat and spring I, the left end of the right half is the mounting hole of the secondary pressure regulating valve, and the right end is the mounting hole of the sliding valve; the left housing thread seal is connected to the outer circle of the left end of the right housing, and the left housing cavity is formed between the left and right housings by the step shift at the leftmost end of the right housing; the outer circle thread seal at the right end of the right housing is fixed in the mounting groove of the speed governor housing; left and right annular oil chambers are left between the right housing and the speed governor housing, and the right housing is also provided with a connecting oil hole, a plurality of left oil holes, a middle oil hole and a right return oil hole; the left spring seat is a reducing cone, and its small gap is assembled at the left end of the inner hole of the left housing; the right spring seat is a "J" shape, and its The right end is placed on the step at the leftmost end of the inner hole of the right housing; spring I is sleeved on the left and right seats of the spring; the secondary pressure regulating valve is installed in the inner hole of the left end of the right half of the right housing, the left end of its valve head is pressed against the inner cavity of the right seat of the spring, the right end of its valve sleeve is against the left end of the sliding valve, and the ring oil chamber I, ring oil chamber II and ring oil chamber III are arranged between its valve sleeve and the right housing; the sliding valve micro-gap is installed in the inner hole of the right housing, and the right housing end on its right side is fixed with a sliding valve shifting member, and the right housing inner hole on its right side is a high-pressure oil chamber; the left oil hole connects the left ring oil chamber and the ring oil chamber I, the left ring oil chamber connects the large torque oil circuit, the middle oil hole connects the right ring oil chamber and the ring oil chamber III, and the right return oil hole connects the right ring oil chamber; the right ring oil chamber connects the oil inlet of the gear pump; the high-pressure oil chamber connects the outlet of the gear pump; under normal conditions, the sliding valve seals the right return oil hole, and the sliding valve moves left to connect the right return oil hole to the high-pressure oil chamber; the ring oil chamber II is connected to the left housing cavity through the connecting oil hole;

[0006] The secondary pressure regulating valve comprises a valve sleeve, a variable-diameter valve core, a valve head, a spring II and a fixing pin; the right end of the valve head and the valve sleeve are fixed together by a fixing pin; the variable-diameter valve core can be slidably sleeved in the valve sleeve, and the left end and the middle part of the variable-diameter valve core are provided with left and right bosses with larger diameters; a connecting hole is provided between the left boss and the valve sleeve, and the right boss and the valve sleeve are slidably and tightly fitted; the left and right bosses divide the valve core and the valve sleeve into a left and a right annular cavity, and a left and a right oil inlet hole and an oil return hole are provided on the wall of the valve sleeve, and a spring II is sleeved on the valve core in the right annular cavity; the left oil inlet hole connects the left annular cavity and the oil annular cavity I, the right oil inlet hole connects the oil annular cavity II, and the oil return hole connects the oil annular cavity III; in a normal state, the right boss blocks the right oil inlet hole from being connected to the left annular cavity, and the right oil inlet hole is connected to the right annular cavity. When the valve core moves to the right, the right oil inlet hole is connected to the left annular cavity, but not to the right annular cavity.

[0007] Further preferably, the sliding valve shifting member is a positioning pin.

[0008] Further preferably, the left boss of the secondary pressure regulating valve has four grooves, and the connecting holes are formed between the four grooves and the valve sleeve.

[0009] In the first-stage pressure regulation of Spring I of the present invention, a second-stage pressure regulating valve is added. Adjust the pressure of Spring I to reach a specified value, such as 4 MPa, and adjust the oil pressure in the high-pressure oil chamber, that is, the fixed-distance high-pressure oil pressure, to be the same as the pressure of Spring I. The entire system remains balanced, the fixed-distance oil pressure is constant, and this balance is maintained during the normal operation of the propeller. The present invention can achieve the purpose of regulating different constant-pressure pressures by changing the pre-compression amount of Spring I, and has a wide range of applications.

[0010] When the pressure in the large-distance oil circuit is low due to some reason but does not reach the specified threshold value, at this time, the fixed-distance oil pressure is high, the large-distance oil pressure is low, and the pressure difference between the fixed-distance and large-distance oil circuits is large. The fixed-distance oil pressure at the right end of the right housing is greater than the spring force of Spring I at the right end. Under the action of the fixed-distance high-pressure oil pressure, the spool valve, the second-stage pressure regulating valve, and the spring right seat move leftward simultaneously, compressing Spring I. At the same time, the spool valve leaves the right oil return hole, and the high-pressure oil chamber communicates with the right annular oil chamber through the right oil return hole, and oil is drained from the right annular oil chamber to the oil inlet of the gear pump. The fixed-distance oil pressure becomes smaller to a constant value, and Spring I returns to its original position to continue to maintain the balance.

[0011] When the pressure in the large-distance oil circuit rises to the specified value due to propeller pitch change jamming or some other reason, at this time, the fixed-distance oil pressure remains unchanged, the large-distance oil pressure increases, and the pressure difference between the fixed-distance and large-distance oil circuits is small. The large-distance oil circuit feeds oil into the annular oil chamber I through the left oil passage hole, and thus enters the left annular cavity of the second-stage pressure regulating valve, pushing the valve core to move rightward, and the right boss moves rightward, compressing Spring II. When the right boss moves rightward to the point where the right oil inlet hole communicates with the left annular cavity, the large-distance pressure lubricating oil enters the left housing cavity through the communication oil hole (under normal conditions, there is no lubricating oil in the left housing cavity). At this time, the acting force at the left end of the second-stage pressure regulating valve increases, and the oil drainage point of the high-pressure oil chamber (fixed-distance oil circuit pressure) rises. As the lubricating oil pressure in the large-distance oil circuit increases, the lubricating oil pressure in the fixed-distance oil circuit also increases accordingly, until the communication size between the left and right oil inlet holes reaches the maximum, and the lubricating oil pressure (large-distance pressure) entering the left housing cavity reaches the maximum. Therefore, the oil drainage point of the high-pressure oil chamber (fixed-distance oil circuit) reaches the highest, and the fixed-distance oil circuit pressure reaches the highest. By this method, the pressure difference between the fixed-distance oil pressure and the large-distance oil pressure is maintained, so that the large-distance oil pressure can reach the required pressure value for pitch change within a short time, meeting the performance requirements of rapid regulation of the governor.

[0012] When the propeller is feathered, a very high oil pressure is required, such as 6 MPa. The pressure in the large-distance oil circuit rises, the fixed-distance oil pressure remains unchanged, and the pressure difference between the fixed-distance and large-distance oil circuits is small. As described above, under the action of the present invention, the oil drainage point of the fixed-distance oil circuit can reach a very high level, and the fixed-distance oil circuit will not drain oil quickly due to the high system oil pressure, and the high oil pressure of the system can be maintained, with a fast response speed, greatly reducing the propeller feathering time.

[0013] The first - stage pressure regulation of the present invention is constant - pressure regulation, and the second - stage pressure regulation is stepless regulation. The pressure of the second - stage pressure regulation will increase correspondingly with the increase of the pressure in the large - pitch oil circuit until the pressure reaches the maximum. The purpose of setting the maximum pressure is to protect the transmission mechanism (such as gears, transmission shafts, etc.) and avoid breakage due to overload.

[0014] The present invention can not only keep the pressure difference between the constant - pitch oil pressure and the large - pitch oil pressure constant when the propeller is normal, but also adjust it in a timely and accurate manner when the large - pitch oil pressure rises sharply, keep the pressure difference between the constant - pitch oil pressure and the large - pitch oil pressure constant, and can also increase the feathering pressure of the propeller and reduce the feathering time. The present invention has precise and rapid control of the propeller speed, high reliability, and a two - stage pressure - regulating safety mechanism is set to deal with complex hydraulic system failures, which can better ensure flight safety; and its structure is simple. Brief Description of the Drawings

[0015] Figure 1 is a schematic diagram of the internal structure of the present invention;

[0016] Figure 2 is a schematic diagram of the internal structure of the two - stage pressure - regulating valve in the present invention;

[0017] Figure 3 is the front view of the valve core in the present invention;

[0018] Figure 4 is Figure 3 the A - A cross - sectional view of Detailed Description of the Invention

[0019] The following further describes the present invention in conjunction with the drawings and specific embodiments.

[0020] Such as Figure 1 、 Figure 2 、 Figure 3 and Figure 4As shown in the figure, this embodiment includes a left housing 1, a left spring seat 2, a first-stage spring 3, a right housing 4, a right spring seat 5, a secondary pressure regulating valve 7, a spool valve 9, and a spool valve positioner 12. Preferably, the spool valve positioner 12 is a positioning pin. The left half of the inner hole of the right housing 4 is an installation hole for the right spring seat 5 and the first-stage spring 3. The left end of the right half is an installation hole for the secondary pressure regulating valve 7, and the right end is an installation hole for the spool valve 9. The left housing 1 is thread-sealed and connected to the outer circle at the upper end of the right housing 4 and is blocked by the step at the uppermost end of the right housing 4, forming a left housing cavity between the left and right housings 1 and 4. The outer circle at the right end of the right housing 4 is thread-sealed and fixed in the installation groove of the governor housing 31. There are left and right annular oil cavities 29 and 30 left between the right housing 4 and the governor housing 31. The right housing 4 is also provided with a communicating oil hole 6, three uniformly distributed left oil passage holes 15, two middle oil passage holes 8, and four right oil return holes 10. The left spring seat 2 is a variable-diameter cone and is assembled with a small clearance at the left end of the inner hole of the left housing 1. The right spring seat 5 is in a shape of "ji" and its right end is placed on the step at the leftmost end of the inner hole of the right housing 4. The first-stage spring 3 is sleeved on the left and right spring seats 2 and 5. The secondary pressure regulating valve 7 is installed in the inner hole at the left end of the right half of the right housing 4. The left end of its valve head 17 abuts against the inner cavity of the right spring seat 5. The right end of its valve sleeve 21 abuts against the left end of the spool valve 9. There are annular oil cavity I 16, annular oil cavity II 14, and annular oil cavity III 13 provided between its valve sleeve 21 and the right housing 4. The spool valve 9 is installed in the inner hole of the right housing 4 with a small clearance. The spool valve positioner 12 is fixed at the end of the right housing 4 on the right side of the spool valve 9, and the inner hole of the right housing 4 on the right side of the spool valve 9 is a high-pressure oil cavity. The left oil passage holes 15 communicate the left annular oil cavity 29 and the annular oil cavity I 16. The left annular oil cavity 29 communicates with the large torque oil passage through the oil hole 32. The middle oil passage holes 8 communicate the right annular oil cavity 30 and the annular oil cavity III 13. The right oil return holes 10 communicate the right annular oil cavity 30. The right annular oil cavity 30 communicates with the gear pump inlet. The high-pressure oil cavity 11 communicates with the gear pump outlet through the oil hole 33. In the normal state, the spool valve 9 blocks the right oil return hole 10, and when the spool valve 9 moves leftward, the right oil return hole 10 communicates with the high-pressure oil cavity 11. The annular oil cavity II 14 communicates with the left housing cavity through the communicating oil hole 6.

[0021] The secondary pressure regulating valve 7 includes a valve sleeve 21, a stepped spool 19, a valve head 17, a spring II 20 and a fixing pin 18; the right end of the valve head 17 and the valve sleeve 21 are fixed together by the fixing pin 18. The stepped spool 19 is slidably sleeved in the valve sleeve 21, and has larger left and right bosses 22 and 25 at its left end and middle part. There is a connecting hole between the left boss 22 and the valve sleeve 21, and the right boss 25 is in a slidable tight fit with the valve sleeve 21; preferably, the left boss 22 of the secondary pressure regulating valve 7 has four grooves 34, and the four grooves 34 form the connecting hole 34 with the valve sleeve 21. The left and right bosses 22 and 25 divide the space between the spool 19 and the valve sleeve 21 into left and right annular cavities 27 and 28, and left and right oil inlet holes 24, 23 and an oil return hole 26 are formed in the wall of the valve sleeve 21. A spring II 20 is sleeved on the spool 19 in the right annular cavity 28. The left oil inlet hole 24 communicates with the left annular cavity 27 and the annular oil cavity I 16, the right oil inlet hole 23 communicates with the annular oil cavity II 14, and the oil return hole 26 communicates with the annular oil cavity III 13; in the normal state, the right boss 25 blocks the communication between the right oil inlet hole 23 and the left annular cavity 27, and the right oil inlet hole 23 communicates with the right annular cavity 28. When the spool 19 moves to the right, the right oil inlet hole 23 communicates with the left annular cavity 27 and is not in communication with the right annular cavity 28.

[0022] Certainly, the present invention has many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make corresponding changes and deformations according to the present invention, but these corresponding changes and deformations should all belong to the improvement of equivalent technologies and fall within the protection scope of the claims of the present invention.

Claims

1. A differential pressure precision adjustment device for a propeller governor, characterized in that: it includes a left housing, a left spring seat, Spring I, a right housing, a right spring seat, a secondary pressure regulating valve, a spool valve and a spool valve positioner; the left half of the inner hole of the right housing is the installation hole for the right spring seat and Spring I, the left end of the right half is the installation hole for the secondary pressure regulating valve, and the right end is the installation hole for the spool valve; the left housing is thread-sealed and connected to the outer circle at the left end of the right housing and is blocked by the step at the leftmost end of the right housing, and a left housing cavity is formed between the left and right housings; the outer circle at the right end of the right housing is thread-sealed and fixed in the installation groove of the governor housing; there are left and right annular oil cavities between the right housing and the governor housing, and the right housing is also provided with a communication oil hole, a plurality of left oil holes, a middle oil hole and a right oil return hole; the left spring seat is of variable diameter conical shape and is assembled with a small clearance at the left end of the inner hole of the left housing; the right spring seat is in a shape of "Ji", and its right end is placed on the step at the leftmost end of the inner hole of the right housing; Spring I is sleeved on the left and right spring seats; the secondary pressure regulating valve is installed in the inner hole at the left end of the right half of the right housing, the left end of its valve head abuts against the inner cavity of the right spring seat, the right end of its valve sleeve abuts against the left end of the spool valve, and annular oil cavities I, II and III are arranged between its valve sleeve and the right housing; the spool valve is installed in the inner hole of the right housing with a small clearance, a spool valve positioner is fixed at the end of the right housing on its right side, and the inner hole of the right housing on its right side is a high-pressure oil cavity; the left oil hole communicates the left annular oil cavity and annular oil cavity I, the left annular oil cavity communicates with the large torque oil circuit, the middle oil hole communicates the right annular oil cavity and annular oil cavity III, and the right oil return hole communicates the right annular oil cavity; the right annular oil cavity communicates with the oil inlet of the gear pump; the high-pressure oil cavity communicates with the oil outlet of the gear pump; Under normal conditions, the spool valve blocks the right oil return hole, and when the spool valve moves to the left, the right oil return hole communicates with the high-pressure oil cavity; annular oil cavity II communicates with the left housing cavity through the communication oil hole; The secondary pressure regulating valve includes a valve sleeve, a variable diameter valve core, a valve head, Spring II and a fixing pin; the right end of the valve head and the valve sleeve are fixed together by the fixing pin; the variable diameter valve core is slidably sleeved in the valve sleeve, and its left end and middle part have relatively large left and right bosses; there is a connection hole between the left boss and the valve sleeve, and the right boss and the valve sleeve are slidably and tightly fitted; the left and right bosses divide the space between the valve core and the valve sleeve into left and right annular cavities, and left and right oil inlet holes and an oil return hole are opened on the valve sleeve wall, and Spring II is sleeved on the valve core in the right annular cavity; the left oil inlet hole communicates the left annular cavity and annular oil cavity I, the right oil inlet hole communicates annular oil cavity II, and the oil return hole communicates annular oil cavity III; under normal conditions, the right boss blocks the communication between the right oil inlet hole and the left annular cavity, the right oil inlet hole communicates with the right annular cavity, and when the valve core moves to the right, the right oil inlet hole communicates with the left annular cavity and is not connected to the right annular cavity.

2. The differential pressure precision adjustment device for a propeller governor according to claim 1, characterized in that: the spool valve positioner is a positioning pin.

3. The differential pressure precision adjustment device for a propeller governor according to claim 1 or 2, characterized in that: the left boss of the secondary pressure regulating valve has four grooves, and these four grooves form the connection hole with the valve sleeve.

Images