CN116221223A - A Two-Stage Servo Hydraulic Cylinder with Double Redundancy and Its Application - Google Patents

Abstract

The invention discloses a two-stage servo hydraulic cylinder with double redundancy and its application, and relates to the technical field of two-stage electrostatic fluid actuators, comprising an outer cylinder body, an inner piston cylinder and an inner piston rod; On the inner side of the outer cylinder, and the inner piston cylinder and the outer cylinder form a first-level telescopic structure, and the two ends of the outer cylinder have a pump/return port that controls the telescopic action of the first-level telescopic structure; the inner piston rod is sleeved inside the inner piston cylinder , and the inner piston rod and the inner piston cylinder form a secondary telescopic structure, and the exposed end of the inner piston cylinder has a pump/return port for controlling the telescopic movement of the secondary telescopic structure. The invention overcomes the defect that the traditional two-stage hydraulic cylinder can only be controlled at the same time, and can independently control the expansion and contraction of each stage of the two-stage hydraulic cylinder, and its controllability and performance are stronger; the overall structure is simple and meets the use requirements , and easy to manufacture and process.

Description

A Two-Stage Servo Hydraulic Cylinder with Double Redundancy and Its Application

technical field

The invention relates to the technical field of two-stage electrostatic hydraulic actuators, in particular to a two-stage servo hydraulic cylinder with double redundancy and its application.

Background technique

The two-stage electrohydrostatic actuator (EHA) needs independent design and integrated manufacturing. Due to the long stroke of the EHA and the limited installation space, the hydraulic cylinder needs to be specially designed, and the double-acting asymmetrical single-rod type two-stage hydraulic pressure is selected. cylinder form. It is characterized by long stroke and short retracted length. It can realize a longer stroke than single-stage hydraulic cylinder in a given space. It is suitable for equipment with limited installation space but long stroke requirements. In the installation space Widely used in tense situations. However, for the swing engine, the stroke control and rigidity requirements are high. It is different from the ordinary two-stage hydraulic cylinder, but needs a servo-type two-way controllable two-stage cylinder.

In the prior art, the two-stage hydraulic cylinder is a telescopic structure that simultaneously controls the entry and exit, such as:

The application date is 2011.11.22, and the application number is 201110374267.3 patent application for invention, which discloses a double-stage double-acting hydraulic cylinder: the hydraulic cylinder includes a cylinder body, a first piston rod and a second piston rod, and the first piston rod It is nested in the cylinder and forms a first oil chamber with the cylinder. An inner plug is fixed in the head end of the first piston rod, and an oil hole corresponding to the oil port of the first piston rod is opened in the inner plug. The hole and the oil passage communicated with the inner cavity of the first piston rod, and the oil pipe communicated with the oil hole is also welded in the inner plug, the second piston rod is nested in the first piston rod, and forms a gap between the first piston rod and the first piston rod. The second oil chamber, the second piston rod also has an oil port and an inner cavity, and the inner cavity communicates with the second oil chamber through the oil port. The oil pipe extends into the inner cavity of the second piston rod and the end port is always at this In the inner cavity, the head end of the second piston rod is sealed with the outer wall of the oil pipe. Compared with the existing common double-stage double-acting hydraulic cylinder, the double-stage double-acting hydraulic cylinder has a more compact and reasonable overall structure and a greatly reduced volume.

The application date is 2022.01.17, and the application number is 202210048238.6, which discloses a double-acting multi-stage oil cylinder, including a secondary piston, a primary piston and a primary piston rod. The oil port also includes a first sealing structure arranged on the secondary piston and a second sealing structure arranged on the primary piston or the secondary piston to keep the primary piston and the secondary piston sealed, and the primary piston rod The inner wall of the first oil outlet is provided with an annular oil passage groove communicating with the first oil outlet to prevent the first sealing structure from contacting the sharp edge of the first oil outlet. The distance between one side of the sealing structure away from the first sealing structure is greater than the axial length of the annular oil passing groove. The above-mentioned double-acting multi-stage oil cylinder can always keep at least one seal functioning. At the same time, it can prevent the first sealing structure from contacting with the sharp edge of the oil outlet, which will cause the first sealing structure to be damaged and lose the sealing effect, so that the sealing structure can be effectively protected. , greatly improving the service life of the seal.

After searching, it is found that most of the existing two-stage hydraulic cylinders use the above-mentioned forms, and no hydraulic cylinders that independently perform telescopic movements of the cylinder bodies of each stage have been developed. Use development plays a key role. In addition, when the cylinder blocks of each stage of the two-stage hydraulic cylinder perform independent telescopic movements, the requirements for the convenience of disassembly and assembly and sealing performance are even higher.

Therefore, how to provide a two-stage hydraulic cylinder in which the cylinder bodies of each stage can perform independent telescopic movement is an urgent problem to be solved by those skilled in the art.

Contents of the invention

In view of this, the present invention provides a two-stage servo hydraulic cylinder with double redundancy and its application, aiming at solving the above technical problems.

In order to achieve the above object, the present invention adopts the following technical solutions:

A two-stage servo hydraulic cylinder with double redundancy, comprising: an outer cylinder body, an inner piston cylinder and an inner piston rod;

The inner piston cylinder sleeve is arranged inside the outer cylinder body, and the inner piston cylinder and the outer cylinder body form a first-stage telescopic structure, and the two ends of the outer cylinder body have Action pump/return port; the inner piston rod is sleeved inside the inner piston cylinder, and the inner piston rod and the inner piston cylinder form a secondary telescopic structure, and the exposed end of the inner piston cylinder There is a pump/return port for controlling the expansion and contraction of the secondary expansion structure.

Through the above technical solution, the present invention provides a new type of two-stage hydraulic cylinder structure, which overcomes the defect that the traditional two-stage hydraulic cylinder can only be controlled at the same time, and can independently control the expansion and contraction of each stage of the two-stage hydraulic cylinder. The controllability and performance are stronger; the invention integrates the liquid port of the two-stage extension pump and the liquid port of the two-stage contraction pump at one end through the structural design of the inner piston cylinder, which solves the problem of two-stage independent control of the hydraulic cylinder oil circuit. It is difficult to design, and the overall structure is simple, which meets the needs of use and is convenient for manufacturing and processing.

Preferably, in the above-mentioned two-stage servo hydraulic cylinder with double redundancy, the sliding end of the inner piston cylinder that cooperates with the outer cylinder body is connected with a first piston head, and the inner piston rod is connected to the inner cylinder. The sliding end matched with the piston cylinder is connected with a second piston head.

Preferably, in the above-mentioned two-stage servo hydraulic cylinder with double redundancy, a first-stage piston chamber is formed inside the outer cylinder body, and the two pump/return ports at both ends of the outer cylinder body are respectively a The liquid port of the first-stage extension pump and the liquid port of the first-stage contraction pump. of two chambers.

Preferably, in the above-mentioned two-stage servo hydraulic cylinder with double redundancy, a secondary piston chamber is formed inside the inner piston cylinder, and the two pump/return ports at the exposed end of the inner piston cylinder They are respectively the liquid port of the secondary extension pump and the liquid port of the secondary contraction pump. The liquid port corresponds to the two chambers.

Preferably, in the above-mentioned two-stage servo hydraulic cylinder with double redundancy, a flow channel is opened inside the side wall of the inner piston cylinder, and the flow channel communicates with the liquid port of the second-stage extension pump and the inner piston cylinder. The piston cylinder is located in the secondary piston cavity at the inner side of the outer cylinder body.

Preferably, in the above-mentioned two-stage servo hydraulic cylinder with double redundancy, the outer side walls of the first piston head and the second piston head are embedded with a rectangular sealing ring and a combined sealing ring for holes.

Preferably, in the above-mentioned two-stage servo hydraulic cylinder with double redundancy, there are two rectangular sealing rings, and the combined sealing ring for holes is located between the two rectangular sealing rings.

Preferably, in the above-mentioned two-stage servo hydraulic cylinder with double redundancy, the inner wall of the opening end of the outer cylinder body and the inner piston cylinder is embedded with a sealing dust ring, a combined shaft sealing ring and a rectangular sealing ring.

Preferably, in the above-mentioned two-stage servo hydraulic cylinder with double redundancy, the sealing and dust-proof ring is located on the outermost side, the rectangular sealing ring is located on the innermost side, and the combined shaft-use sealing ring is located on the sealing and dust-proofing ring. Between the dust ring and the rectangular sealing ring.

The present invention also provides an application of the above-mentioned two-stage servo hydraulic cylinder with double redundancy in a two-stage electrostatic hydraulic actuator.

Through the above technical solution, the dual-redundancy dual-stage servo hydraulic cylinder provided by the present invention is applied in the dual-stage electrostatic hydraulic actuator, which can meet the high requirements of the swing engine for stroke control and rigidity. The development of the use of hydraulic actuators plays a key role.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only It is an embodiment of the present invention, and those skilled in the art can also obtain other drawings according to the provided drawings without creative work.

Fig. 1 accompanying drawing is the structural representation of the dual-stage servo hydraulic cylinder of embodiment 1 double redundancy provided by the present invention;

Fig. 2 accompanying drawing is the cross-sectional view of the dual-stage servo hydraulic cylinder with double redundancy in Embodiment 1 provided by the present invention;

Figure 3 is a cross-sectional view at another angle of the double-redundancy dual-stage servo hydraulic cylinder of Embodiment 1 provided by the present invention;

Accompanying drawing of Fig. 4 is the enlarged view of part A in Fig. 2 provided by the present invention;

Fig. 5 accompanying drawing is the enlarged view of part B in Fig. 2 provided by the present invention;

Fig. 6 accompanying drawing is the enlarged view of part C in Fig. 2 provided by the present invention;

Fig. 7 accompanying drawing is the enlarged view of part D in Fig. 2 provided by the present invention;

Fig. 8 accompanying drawing is the enlarged view of part E in Fig. 2 provided by the present invention;

Fig. 9 accompanying drawing is the enlarged view of part F in Fig. 2 provided by the present invention;

Figure 10 accompanying drawing is the enlarged view of part G in Figure 2 provided by the present invention;

Figure 11 accompanying drawing is the enlarged view of part H in Figure 2 provided by the present invention;

Figure 12 is a schematic diagram of the oil circuit of the dual-stage electrohydrostatic actuator with similar redundancy in Embodiment 2 provided by the present invention;

Figure 13 is a schematic diagram of the oil circuit of the switching sub-position of the dual-stage electrohydrostatic actuator with similar redundancy in Embodiment 2 provided by the present invention;

Figure 14 is a schematic diagram of the oil circuit for switching another sub-position of the dual-stage electrohydrostatic actuator with similar redundancy in Embodiment 2 provided by the present invention;

Figure 15 is a schematic diagram of the oil circuit of the dual-stage electrohydrostatic actuator with non-similar margin in Embodiment 3 provided by the present invention;

Figure 16 is a schematic diagram of the oil circuit of the switching sub-position of the dual-stage electrohydrostatic actuator with non-similar margin in Embodiment 3 provided by the present invention;

Figure 17 is a schematic diagram of the oil circuit for switching another sub-position of the dual-stage electrohydrostatic actuator with non-similar margin in Embodiment 3 provided by the present invention;

Figure 18 is a schematic diagram of the hydraulic oil circuit of the two-way pump system provided by the present invention;

Figure 19 is a schematic diagram of the hydraulic oil circuit of the one-way pump system provided by the present invention.

in:

1-two-stage cylinder;

10-outer cylinder body;

100-outer cylinder; 1000-first-level piston cavity; 1001-first flange; 101-fixed end cover of outer cylinder; 1010-first-level extension pump liquid port; 1011-first plug-in section; Ring groove; 1013-the first O-ring; 102-extensible end cover of the outer cylinder; 1020-first-level contraction pump liquid port; 1021-first-level piston port; 1022-second insertion section; 1023-second ring groove ;1024-the second O-ring; 1025-the third ring groove; 1026-the combined seal ring for the first shaft; 1027-the first rectangular seal ring; 1028-the first sealing dust ring; 103-the first bolt group ;

20-inner piston cylinder;

200-inner cylinder; 2000-secondary piston cavity; 2001-flow channel; 2002-second flange; 201-first piston head; 2010-third plug-in section; 2011-fourth ring groove; Three O-shaped sealing rings; 2013-the fifth ring groove; 2014-the combined sealing ring for the first hole; 2015-the second rectangular sealing ring; 202-the telescopic end cover of the inner cylinder; - the liquid port of the secondary contraction pump; 2022 - the secondary piston port; 2023 - the fourth insertion section; 2024 - the sixth ring groove; 2025 - the fourth O-ring; 2026 - the seventh ring groove; 2027 - Combined sealing ring for the second shaft; 2028-the third rectangular sealing ring; 2029-the second sealing dustproof ring; 203-the second bolt group; 204-the third bolt group;

30 - inner piston rod;

300-the second piston head; 3000-the eighth ring groove; 3001-the fifth O-ring; 3002-the ninth ring groove; 3003-the combined sealing ring for the second shaft; 3004-the fourth rectangular sealing ring; 301- Jack nut;

40-three-position eight-way reversing valve;

400-main position; 401-vice position;

50-two-way pump system;

500-two-way pump; 501-low supply/return circuit; 502-high supply/return circuit; 503-supplement circuit; 504-first one-way valve; 505-oil tank branch; 506-oil tank; 507-oil storage circuit; 508-electromagnetic switch valve; 509-oil drain line; 510-second check valve; 511-filter; 512-safety control oil circuit; 513-overflow valve; 514-mode valve;

60 - one-way pump system;

600-proportional reversing valve; 601-safety valve.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Example 1:

Referring to accompanying drawings 1 to 3, the embodiment of the present invention discloses a two-stage servo hydraulic cylinder with double redundancy, including:

Outer cylinder 10, the outer cylinder 10 is formed with a primary piston cavity 1000, one end of the outer cylinder 10 has a primary piston port 1021 communicating with the primary piston cavity 1000; The first-stage extension pump liquid port 1010 and the first-stage contraction pump liquid port 1020 connected by the piston chamber 1000;

The inner piston cylinder 20 is coaxially sleeved on the inner side of the outer cylinder body 10, and the outer wall of the inner piston cylinder 20 is in sealing and sliding connection with the first-stage piston port 1021, and the inner piston cylinder 20 is located at the end of the first-stage piston chamber 1000. The head is connected with a first piston head 201, and the side wall of the first piston head 201 is in sealing and sliding connection with the side wall of the first-stage piston chamber 1000. Two chambers corresponding to the liquid port 1010 and the first-stage contraction pump liquid port 1020; the inner piston cylinder 20 is formed with a second-stage piston chamber 2000, and the end of the inner piston cylinder 20 located outside the first-stage piston chamber 1000 has a The secondary piston port 2022 connected to the cavity 2000; the side wall at one end of the inner piston cylinder 20 located outside the primary piston cavity 1000 forms a secondary extension pump liquid port 2020 and a secondary contraction pump liquid port 2021, and the secondary expansion pump liquid The port 2020 communicates with the flow channel 2001 opened inside the side wall of the inner piston cylinder 20, and communicates with the second-level piston chamber 2000 of the inner piston cylinder 20 at one end of the first-level piston chamber 1000, and the second-level contraction pump fluid port 2021 communicates with the inner piston cylinder 20 The secondary piston chamber 2000 located at the outer end of the primary piston chamber 1000 communicates with each other;

The inner piston rod 30 is coaxially sleeved on the inner side of the inner piston cylinder 20, and the outer wall of the inner piston rod 30 is in sealing and sliding connection with the secondary piston port 2022, and the inner piston rod 30 is located inside the secondary piston chamber 2000 The end is connected with a second piston head 300, and the side wall of the second piston head 300 is in sealing and sliding connection with the side wall of the secondary piston chamber 2000. The two chambers corresponding to the pump liquid port 2020 and the secondary contraction pump liquid port 2021 .

In order to further optimize the above-mentioned technical scheme, the outer cylinder body 10 includes an outer cylinder barrel 100, an outer cylinder fixed end cap 101 and an outer cylinder telescopic end cap 102; both ends of the outer cylinder barrel 100 have first flanges 1001, and the outer cylinder fixed end cap 101 and the telescopic end cover 102 of the outer cylinder are respectively connected to the two first flanges 1001 through the first bolt group 103, the first-stage extension pump liquid port 1010 is opened on the side wall of the fixed end cover 101 of the outer cylinder, and the first-stage contraction pump The liquid port 1020 is opened on the side wall of the telescopic end cover 102 of the outer cylinder.

Referring to accompanying drawing 4, the connecting end of the fixed end cover 101 of the outer cylinder and the outer cylinder 100 has a first insertion section 1011 inserted into the inner side of the outer cylinder 100, and the outer wall of the first insertion section 1011 is provided with a first annular groove 1012 , the first ring groove 1012 is embedded with a first O-ring 1013 .

Referring to accompanying drawings 5 and 6, the connecting end of the outer cylinder telescopic end cover 102 and the outer cylinder 100 has a second insertion section 1022 inserted into the inner side of the outer cylinder 100, and the outer wall of the second insertion section 1022 is provided with a second The second ring groove 1023, the second ring groove 1023 is embedded with a second O-ring 1024; the end of the outer cylinder telescopic end cover 102 away from the outer cylinder 100 is the primary piston port 1021, and the inner side wall of the primary piston port 1021 There are a plurality of third ring grooves 1025 , and the first combined sealing ring 1026 for the shaft, the first rectangular sealing ring 1027 and the first sealing dustproof ring 1028 are embedded in the plurality of third ring grooves 1025 .

In order to further optimize the above-mentioned technical scheme, the inner piston cylinder 20 also includes an inner cylinder barrel 200 and an inner cylinder telescopic end cover 202; the inner end of the inner cylinder barrel 200 located in the primary piston chamber 1000 has a second flange 2002, and the first piston head 201 is connected to the second flange 2002 through the second bolt group 203, and the telescopic end cover 202 of the inner cylinder is connected to the telescopic end of the inner cylinder 200 through the third bolt group 204; the flow channel 2001 is opened on the side wall of the inner cylinder 200 , the secondary extension pump liquid port 2020 and the secondary contraction pump liquid port 2021 are all provided on the side wall of the telescopic end cover 202 of the inner cylinder.

Referring to accompanying drawings 7 and 8, the connection end between the first piston head 201 and the inner cylinder 200 has a third insertion section 2010 inserted into the inner cylinder 200, and a fourth insertion section 2010 is provided on the outer wall of the third insertion section 2010. Ring groove 2011, the fourth ring groove 2011 is embedded with a third O-ring 2012; the outer wall of the first piston head 201 is provided with a plurality of fifth ring grooves 2013, and a plurality of fifth ring grooves 2013 are embedded with The first hole is combined with a sealing ring 2014 and a second rectangular sealing ring 2015 .

Referring to accompanying drawings 9 and 10, the connecting end of the inner cylinder telescopic end cover 202 and the inner cylinder 200 has a fourth insertion section 2023 inserted into the inside of the inner cylinder 200, and the outer wall of the fourth insertion section 2023 is provided with a second The sixth ring groove 2024, the fourth O-ring 2025 is embedded in the sixth ring groove 2024; There are a plurality of seventh ring grooves 2026 , and the second combined sealing ring 2027 for the shaft, the third rectangular sealing ring 2028 and the second sealing dustproof ring 2029 are embedded in the plurality of seventh ring grooves 2026 .

In order to further optimize the above technical solution, the second piston head 300 is sheathed on the end of the inner piston rod 30 inside the secondary piston chamber 2000 and locked by a jacking nut 301 .

Referring to accompanying drawing 11, the inner ring of the second piston head 300 is provided with an eighth ring groove 3000, and the fifth O-ring 3001 is embedded in the eighth ring groove 3000, and the outer wall of the second piston head 300 is provided with a plurality of The ninth ring groove 3002, a plurality of ninth ring grooves 3002 are embedded with a second shaft combined seal ring 3003 and a fourth rectangular seal ring 3004.

Example 2:

Referring to accompanying drawing 12, on the basis of adopting the two-stage cylinder 1 provided in embodiment 1, this embodiment provides a two-stage electrohydrostatic actuator with similar redundancy, which also includes:

Three-position eight-way reversing valve 40, the three-position eight-way reversing valve 40 has a main position 400 with four inputs and four outputs, and two auxiliary positions 401 with two inputs and four outputs;

Two-way pump system 50, the quantity of two-way pump system 50 is two sets, the inlet and outlet oil passages of two sets of two-way pump system 50 are respectively connected with the four passages of the three-position eight-way reversing valve 40 main position 400, and respectively connected with the primary extension The pump liquid port 1010 is connected with the first-stage contraction pump liquid port 1020, and the second-stage extension pump liquid port 2020 is connected with the second-stage contraction pump liquid port 2021, so that the two bidirectional pump systems 20 can respectively expand and contract the two-stage cylinder 1. for independent control.

In order to further optimize the above technical solution, the two sub-positions 401 with two inputs and four outputs are respectively used to switch corresponding positions when any bidirectional pump system 50 is damaged, so as to uniformly control the two-stage expansion and contraction of the two-stage cylinder 1 .

In order to further optimize the above technical solution, the two-way pump system 50 controls the flow rate of the pump oil through speed regulation of the two-way pump.

The three-position, eight-way reversing valve 40 provided in this embodiment is shown in FIG. 12 , and will not be repeated here. Referring to accompanying drawing 13, when the two-way pump system 50 on the right is damaged, the three-position eight-way reversing valve 40 is switched to the auxiliary position 401 as shown in accompanying drawing 13, at this moment, by the two-way pump system 50 on the left side The two-stage expansion and contraction of the two-stage cylinder 1 is uniformly controlled; see accompanying drawing 14, when the two-way pump system 50 on the left is damaged, the three-position eight-way reversing valve 40 is switched to the auxiliary position 401 as shown in the accompanying drawing 14, At this time, the two-stage expansion and contraction of the two-stage cylinder 1 is uniformly controlled by the two-way pump system 50 on the right.

In this embodiment, referring to accompanying drawing 18, the bidirectional circulation pump system includes a bidirectional pump 500, and the two pump/suction ports of the bidirectional pump 500 are respectively connected with a low-volume supply/return circuit 501 and a high-volume supply/return circuit 502 , between the low-volume supply/return oil circuit 501 and the high-volume supply/return oil circuit 502, there is a supplementary oil circuit 503, and two first check valves 504 with opposite directions are installed on the supplementary oil circuit 503, two There is an oil tank branch 505 between the first one-way valves 504, and the oil tank branch 505 is connected to an oil tank 506, and the oil in the oil tank 506 can pass through the two first one-way valves 504 to the low-volume supply/return oil circuit 501 and the oil return circuit 501 respectively. The high-volume oil supply/return circuit 502 flows; the oil tank branch 505 and the high-volume oil supply/return circuit 502 are connected with an oil storage circuit 507, and an electromagnetic switch valve 508 is installed on the oil storage circuit 507.

In order to further optimize the above-mentioned technical scheme, an oil drain pipeline 509 is connected between the oil tank branch 505 and the oil drain port of the bidirectional pump 500, and a second one-way valve 510 is installed on the oil drain pipeline 509, and the oil discharged from the bidirectional pump 500 Flows to the oil tank 506 through the second one-way valve 510 .

In order to further optimize the above technical solution, a filter 511 is installed on the drain line 509 , and the filter 511 is located between the second one-way valve 510 and the two-way pump 500 .

In order to further optimize the above technical solution, there are multiple safety control oil circuits 512 between the low-volume supply/return oil circuit 501 and the high-volume supply/return oil circuit 502, and relief valves are respectively installed on the multiple safety control oil circuits 512 513 and mode valve 514.

In order to further optimize the above technical solution, there are two overflow valves 513, and the overflow directions of the two overflow valves 513 are opposite.

In order to further optimize the above technical solution, the fuel tank 506 is a pressurized fuel tank.

In order to further optimize the above technical solution, the bidirectional pump 500 is driven by a motor.

In order to further optimize the above technical solution, the oil supply and oil return volume of the low volume oil supply/return circuit 501 is smaller than the oil supply and oil return volume of the high volume oil supply/return circuit 502 .

In order to further optimize the above-mentioned technical solution, the electromagnetic switching valve 508 is opened when the high-volume oil supply/return circuit 502 returns oil.

Example 3:

Referring to accompanying drawing 15, on the basis of adopting the two-stage cylinder 1 provided in embodiment 1, this embodiment provides a two-stage electrohydrostatic actuator with non-similar redundancy, which also includes:

Three-position eight-way reversing valve 40, the three-position eight-way reversing valve 40 has a main position 400 with four inputs and four outputs, and two auxiliary positions 401 with two inputs and four outputs;

Control system; the control system includes a two-way pump system 50 and a one-way pump system 60, the inlet and outlet oil passages of the two-way pump system 50 and the one-way pump system 60 are respectively connected with the four passages of the main position 400 of the three-position eight-way reversing valve 40, and They are respectively connected with the primary expansion pump liquid port 1010 and the primary contraction pump liquid port 1020, and the secondary expansion pump liquid port 2020 and the secondary contraction pump liquid port 2021, so that the two-way pump system 50 and the one-way pump system 60 can Independently control the two-stage expansion and contraction of the two-stage cylinder 1 respectively.

The three-position, eight-way reversing valve 40 provided in this embodiment is shown in FIG. 15 , and will not be repeated here. Referring to accompanying drawing 16, when the two-way pump system 50 on the right side is damaged, the three-position eight-way reversing valve 40 is switched to the auxiliary position 401 as shown in the accompanying drawing 16, at this time, the one-way pump system 60 on the left side Unified control of the two-stage expansion and contraction of the two-stage cylinder 1; see accompanying drawing 17, when the one-way pump system 60 on the left is damaged, the three-position eight-way reversing valve 40 is switched to the auxiliary position as shown in the accompanying drawing 17 401. At this time, the two-stage expansion and contraction of the two-stage cylinder 1 is uniformly controlled by the two-way pump system 50 on the right.

The specific structure of the bi-directional pump system 50 provided in this embodiment is the same as that in Embodiment 1, and will not be repeated here.

The specific structure of the one-way pump system 60 provided in this embodiment is shown in FIG. 19 , which is a conventional structure driven by a one-way pump. It switches oil pipelines through a proportional reversing valve 600 to solve the problem of flow mismatch. question. At the same time, a safety valve 601 is used to prevent potential safety hazards caused by excessive pump pressure, so details will not be repeated here.

Each embodiment in this specification is described in a progressive manner, each embodiment focuses on the difference from other embodiments, and the same and similar parts of each embodiment can be referred to each other. As for the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and for relevant details, please refer to the description of the method part.

The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention will not be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (10)

1. A two-stage servo hydraulic cylinder with double redundancy, comprising: an outer cylinder body, an inner piston cylinder and an inner piston rod; The inner piston cylinder sleeve is arranged inside the outer cylinder body, and the inner piston cylinder and the outer cylinder body form a first-stage telescopic structure, and the two ends of the outer cylinder body have Action pump/return port; the inner piston rod is sleeved inside the inner piston cylinder, and the inner piston rod and the inner piston cylinder form a secondary telescopic structure, and the exposed end of the inner piston cylinder There is a pump/return port for controlling the expansion and contraction of the secondary expansion structure. 2. A dual-stage servo hydraulic cylinder with double redundancy according to claim 1, wherein the sliding end of the inner piston cylinder and the outer cylinder body is connected with a first piston head, and the The sliding end of the inner piston rod that cooperates with the inner piston cylinder is connected with a second piston head. 3. A dual-redundancy dual-stage servo hydraulic cylinder according to claim 2, wherein a first-stage piston cavity is formed inside the outer cylinder body, and the two pumps at both ends of the outer cylinder body The liquid return ports are respectively the first-stage extension pump liquid port and the first-stage contraction pump liquid port, and the first piston head separates the first-stage piston cavity from the first-stage extension pump liquid port and the first-stage contraction pump liquid port respectively. The first stage constricts the two chambers corresponding to the liquid port of the pump. 4. A two-stage servo hydraulic cylinder with double redundancy according to claim 2, characterized in that a secondary piston chamber is formed inside the inner piston cylinder, and two exposed ends of the inner piston cylinder The pump/return ports are respectively a secondary extension pump liquid port and a secondary contraction pump liquid port, and the second piston head separates the secondary piston chamber into two separate parts from the secondary elongation pump liquid port respectively. Two chambers corresponding to the liquid port of the secondary constriction pump. 5. A two-stage servo hydraulic cylinder with double redundancy according to claim 4, characterized in that a flow channel is opened inside the side wall of the inner piston cylinder, and the flow channel communicates with the secondary extension The pump fluid port and the inner piston cylinder are located in the secondary piston cavity at the inner side of the outer cylinder body. 6. A two-stage servo hydraulic cylinder with double redundancy according to any one of claims 2-5, characterized in that, the outer walls of the first piston head and the second piston head are embedded with There are rectangular sealing rings and combined sealing rings for holes. 7. A two-stage servo hydraulic cylinder with double redundancy according to claim 6, wherein the number of said rectangular sealing rings is two, and said combined sealing rings for holes are located between two said rectangular sealing rings. between the sealing rings. 8. A two-stage servo hydraulic cylinder with double redundancy according to any one of claims 1-5, characterized in that, the inner wall of the opening end of the outer cylinder body and the inner piston cylinder is embedded with There are sealing dust rings, combined sealing rings for shafts and rectangular sealing rings. 9. A two-stage servo hydraulic cylinder with double redundancy according to claim 8, characterized in that, the sealing dust-proof ring is located on the outermost side, the rectangular sealing ring is located on the innermost side, and the shaft is combined with The sealing ring is located between the sealing dust-proof ring and the rectangular sealing ring. 10. An application of the dual-stage servo hydraulic cylinder with dual redundancy according to any one of claims 1-9 in a dual-stage electrostatic hydraulic actuator.

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