Small-size large-flow electro-hydraulic servo valve

Abstract

The utility model relates to the technical field of electro-hydraulic servo valves, in particular to a small-size large-flow electro-hydraulic servo valve which comprises a torque motor assembly, a nozzle-baffle assembly, a flow amplification assembly and a shell. According to the electro-hydraulic servo valve of the structure, large-flow output of a small-size single-stage servo valve is achieved, the application range of the single-stage electro-hydraulic servo valve is widened, meanwhile, the throttling holes are formed in the valve element, liquid flow is stabilized, pressure fluctuation caused by rapid change of the liquid flow is reduced, and the anti-jamming capability and the control stability of the single-stage servo valve are improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to electro-hydraulic servo valve technical field, concretely relates to a small size big flow electro-hydraulic servo valve. BACKGROUND

[0002] The electro-hydraulic servo valve is the core component of the hydraulic servo control system, and plays the roles of electro-hydraulic conversion and power amplification in the system. When the system works, it directly receives the electrical signals transmitted from the system, and converts the electrical signals into signals with corresponding polarity, proportionality, load flow or load pressure capable of controlling the electro-hydraulic servo valve. The electro-hydraulic servo valve has high control precision, good stability, fast response speed and large power density, and is widely used in industrial automation, aerospace, ships and other industrial fields.

[0003] According to the structural form of the electro-hydraulic servo valve, it can be divided into single-stage servo valve, two-stage servo valve and multi-stage servo valve. The single-stage electro-hydraulic servo valve is composed of a torque motor and a nozzle-flapper hydraulic amplifier. The mechanical energy output by the torque motor drives the flapper to move, changes the relative position of the nozzle-flapper, and thus controls the output flow. The single-stage servo valve has simple structure, small size, small volume and fast response, and has great advantages in space and weight. However, the output flow of the single-stage servo valve is limited by the power of the torque motor, and it is sensitive to load changes, so it is only suitable for low-pressure small-flow and small-load change occasions, which greatly limits the wide application of the single-stage servo valve. SUMMARY

[0004] The utility model solves the technical problem: the utility model provides a small size big flow electro-hydraulic servo valve, the structure electro-hydraulic servo valve realizes the big flow output of small size single-stage servo valve, improves the application scope of single-stage electro-hydraulic servo valve, and sets up the throttle hole on the valve core, stabilizes the liquid flow, reduces the pressure fluctuation caused by rapid change of liquid flow, and improves the anti-interference ability and control stability of single-stage servo valve.

[0005] The technical scheme of the utility model

[0006] A small size big flow electro-hydraulic servo valve, comprising a torque motor assembly, a nozzle-flapper assembly, a flow amplification assembly and a housing, the torque motor assembly is arranged on the housing, the torque motor assembly comprises an upper magnetic conductor, an armature, a lower magnetic conductor, a coil, a spring tube and a support tube, the armature is arranged between the upper magnetic conductor and the lower magnetic conductor, the coil is wound on the armature, the upper end of the spring tube is embedded in the armature, the lower end is connected with the housing, and the support tube is arranged between the spring tube and the armature.

[0007] The nozzle-baffle assembly comprises a left nozzle, a baffle and a right nozzle, the baffle is arranged in the shell, the upper end is fixedly connected with the armature, and the lower end is arranged between the left nozzle and the right nozzle; the left nozzle comprises a first left oil inlet hole, a second left oil inlet hole, a load output A hole, a left oil return hole and a left nozzle hole; the first left oil inlet hole and the second left oil inlet hole are connected with the shell oil inlet hole, the load output A hole is connected with the shell left load hole, and the left oil return hole and the left nozzle hole are connected with the shell oil return hole; the right nozzle comprises a first right oil inlet hole, a second right oil inlet hole, a load output B hole, a right oil return hole and a right nozzle hole; the first right oil inlet hole and the second right oil inlet hole are connected with the shell oil inlet hole, the load output B hole is connected with the shell right load hole, and the right oil return hole and the right nozzle hole are connected with the shell oil return hole.

[0008] The flow amplification assembly comprises a left valve core, a left limiting block, a left spring, a right valve core, a right limiting block and a right spring; the left valve core is slidingly arranged in the left nozzle, and the left valve core is limited by the left limiting block and the left spring arranged in the shell; the right valve core is slidingly arranged in the right nozzle, and the right valve core is limited by the right limiting block and the right spring arranged in the shell.

[0009] The left valve core comprises a left throttle hole, a left valve core first shaft shoulder, a left valve core second shaft shoulder, a left valve core third shaft shoulder, a left valve core oil outlet hole, one end of the left valve core oil outlet hole is communicated with the left nozzle hole, the other end is communicated with the left throttle hole, and the left throttle hole is communicated with the first left oil inlet hole; a cavity formed by the left valve core second shaft shoulder and the left valve core third shaft shoulder is connected with the shell left load hole through the load output A hole, and can communicate the shell left load hole and the shell oil inlet hole or the shell left load hole and the shell oil return hole according to the movement position of the valve core.

[0010] The right valve core comprises a right throttle hole, a right valve core first shaft shoulder, a right valve core second shaft shoulder, a right valve core third shaft shoulder, a right valve core oil outlet hole, one end of the right valve core oil outlet hole is communicated with the right nozzle hole, the other end is communicated with the right throttle hole, and the right throttle hole is communicated with the first right oil inlet hole; a cavity formed by the right valve core second shaft shoulder and the right valve core third shaft shoulder is connected with the shell right load hole through the load output B hole, and can communicate the shell right load hole and the shell oil inlet hole or the shell right load hole and the shell oil return hole according to the movement position of the valve core.

[0011] Further, the coaxiality of the left nozzle and the right nozzle is 0.02 mm; the coaxiality of the left nozzle and the left valve core is 0.02 mm; and the coaxiality of the right nozzle and the right valve core is 0.02 mm, so as to ensure the symmetry of the left and right structures and improve the control precision.

[0012] Further, the distance between the left nozzle, the right nozzle and the baffle is 0.05 mm, so as to ensure that the valve core annular surface outputs sufficient flow.

[0013] Further, the movement stroke of the left valve core and the right valve core is not less than 0.5 mm.

[0014] Further, the diameter ratio of the left throttle hole to the left nozzle hole; the diameter ratio of the right throttle hole to the right nozzle hole;

[0015] Further, the stiffness of the left spring and the right spring is determined by the oil supply pressure, the left nozzle hole and the right nozzle hole diameter; the stiffness difference between the left spring and the right spring does not exceed 1 / 10 of the stiffness of the left spring or 1 / 10 of the stiffness of the right spring.

[0016] Further, the taper angle of the left nozzle and the right nozzle is 150°, which aims to reduce the flow resistance and improve the convergence of the jet.

[0017] Further, the left and right flatness of the baffle plate is less than 0.1mm, which ensures that the baffle plate is uniformly stressed and does not receive oblique liquid flow resistance during movement.

[0018] Advantages

[0019] 1. The utility model differs from the traditional single-stage nozzle-baffle servo valve, the novel structure nests the cylindrical slide valve structure in the nozzle structure, converts the small flow output controlled by the nozzle small hole into the large flow output controlled by the slide valve ring surface, makes up for the disadvantage of small output flow of the traditional single-stage servo valve, and still retains the advantage of small size of the single-stage servo valve.

[0020] 2. The utility model aims at the single-stage electro-hydraulic servo valve which is greatly affected by the oil supply pressure and load pressure fluctuation, sets throttle holes on the valve core, stabilizes the liquid flow, reduces the pressure fluctuation caused by rapid change of the liquid flow, and improves the anti-interference ability and control stability of the single-stage servo valve. DRAWINGS

[0021] Figure 1 The utility model provides an electro-hydraulic servo valve structure schematic view for the utility model embodiment;

[0022] Figure 2 The utility model provides a shell structure schematic view for the utility model embodiment;

[0023] Figure 3 The utility model provides a left nozzle structure schematic view for the utility model embodiment;

[0024] Figure 4 The utility model provides a right nozzle structure schematic view for the utility model embodiment;

[0025] Figure 5 The utility model provides a left valve core structure schematic view for the utility model embodiment;

[0026] Figure 6 The utility model provides a right valve core structure schematic view for the utility model embodiment;

[0027] Figure 7 The utility model provides a flow amplification assembly working principle drawing for the utility model embodiment;

[0028] Wherein, 1 - upper magnetic conductor, 2 - armature, 3 - lower magnetic conductor, 4 - housing, 5 - left nozzle, 6 - left valve core, 7 - left limit block, 8 - left spring, 9 - coil, 10 - spring tube, 11 - support tube, 12 - baffle, 13 - right nozzle, 14 - right limit block, 15 - right spring, 16 - right valve core;

[0029] 4.1 - housing left oil inlet hole, 4.2 - housing right oil inlet hole, 4.3 - housing left load hole, 4.4 - housing oil return hole, 4.5 - housing right load hole;

[0030] 5.1 - first left oil inlet hole, 5.2 - second left oil inlet hole, 5.1 - load output A hole, 5.4 - left oil return hole, 5.5 - left nozzle hole;

[0031] 13.1 - first right oil inlet hole, 13.2 - second right oil inlet hole, 13.3 - load output B hole, 13.4 - right oil return hole, 13.5 - right nozzle hole;

[0032] 6.1 - left throttle hole, 6.2 - left valve core first shaft shoulder, 6.3 - left valve core second shaft shoulder, 6.4 - left valve core third shaft shoulder, 6.5 - left valve core oil outlet hole;

[0033] 16.1 - right throttle hole, 16.2 - right valve core first shaft shoulder, 16.3 - right valve core second shaft shoulder, 16.4 - right valve core third shaft shoulder, 16.5 - right valve core oil outlet hole. DETAILED DESCRIPTION

[0034] The features of each aspect of the present application and illustrative embodiments will be described below in detail. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, it will be apparent to one skilled in the art that the present application can be practiced without some of these specific details. The description of the embodiments is merely to provide a better understanding of the present application by showing examples of the present application. The present application is in no way limited to any specific set of features and methods set forth below, but covers any modifications, replacements and changes of structure, method and device without departing from the spirit of the present application. In the drawings and the following description, well-known structures and techniques are not shown to avoid unnecessary obscuring of the present application.

[0035] It should be noted that the features of the embodiments of the present application and the embodiments can be combined with each other without conflict, and each embodiment can be mutually referenced and quoted. The present application will be described in detail below with reference to the drawings and in combination with the embodiments.

[0036] As Figure 1The utility model discloses an embodiment provides a kind of small size large flow electro-hydraulic servo valve, including torque motor assembly, nozzle-baffle assembly and flow amplification assembly and shell 4;The torque motor assembly is arranged on shell 4, and the torque motor assembly includes upper magnet 1, armature 2, lower magnet 3, coil 9, spring tube 10, support tube 11;The armature 2 is arranged between upper magnet 1 and lower magnet 3, coil 9 is wound on armature 2, spring tube 10 upper end is embedded in armature 2, and lower end is connected with shell 4, and support tube 11 is arranged between spring tube 10 and armature 2;

[0037] The nozzle-baffle assembly includes left nozzle 5, baffle 12 and right nozzle 13, and the baffle 12 is arranged in the shell 4, and the upper end is fixedly connected with the armature 2, and the lower end is arranged between the left nozzle 5 and the right nozzle 13.

[0038] As shown in the figure, Figure 3 The left nozzle 5 includes first left oil inlet hole 5.1, second left oil inlet hole 5.2, load output A hole 5.3, left oil return hole 5.4 and left nozzle hole 5.5; the first left oil inlet hole 5.1, the second left oil inlet hole 5.2 are connected with the shell left oil inlet hole 4.1, the load output A hole 5.3 is connected with the shell left load hole 4.3, and the left oil return hole 5.4 and the left nozzle hole 5.5 are connected with the shell oil return hole 4.4.

[0039] As shown in the figure, Figure 4 The right nozzle 13 includes first right oil inlet hole 13.1, second right oil inlet hole 13.2, load output B hole 13.3, right oil return hole 13.4 and right nozzle hole 13.5; the first right oil inlet hole 13.1, the second right oil inlet hole 13.2 are connected with the shell right oil inlet hole 4.2, the load output B hole 13.3 is connected with the shell right load hole 4.5, and the right oil return hole 13.4 and the right nozzle hole 13.5 are connected with the shell oil return hole 4.4.

[0040] The flow amplification assembly includes left valve core 6, left limit block 7, left spring 8, right valve core 16, right limit block 14, right spring 15, the left valve core 6 is slidably arranged in the left nozzle 5, and the left valve core 6 is limited by the left limit block 7 and the left spring 8 arranged in the shell, the right valve core 16 is slidably arranged in the right nozzle 13, and the right valve core 16 is limited by the right limit block 14 and the right spring 15 arranged in the shell.

[0041] As shown in the figure, Figure 5As shown, the left valve core 6 includes a left throttle hole 6.1, a left valve core first shaft shoulder 6.2, a left valve core second shaft shoulder 6.3, a left valve core third shaft shoulder 6.4, a left valve core oil outlet hole 6.5, one end of the left valve core oil outlet hole 6.5 being communicated with the left nozzle hole 5.5, the other end being communicated with the left throttle hole 6.1, the left throttle hole 6.1 being communicated with the first left oil inlet hole 5.1; the left valve core second shaft shoulder 6.3 and the left valve core third shaft shoulder 6.4 form a cavity, which is connected with the shell left load hole 4.3 through the load output A hole 5.3, and can communicate the shell left load hole 4.3 and the shell left oil inlet hole 4.1, or communicate the shell left load hole 4.3 and the shell oil return hole 4.4 according to the movement position of the valve core;

[0042] As shown in the figure, Figure 6 As shown, the right valve core 16 includes a right throttle hole 16.1, a right valve core first shaft shoulder 16.2, a right valve core second shaft shoulder 16.3, a right valve core third shaft shoulder 16.4, a right valve core oil outlet hole 16.5, one end of the right valve core oil outlet hole 16.5 being communicated with the right nozzle hole 13.5, the other end being communicated with the right throttle hole 16.1, the right throttle hole 16.1 being communicated with the first right oil inlet hole 13.1; the right valve core second shaft shoulder 16.3 and the right valve core third shaft shoulder 16.4 form a cavity, which is connected with the shell right load hole 4.5 through the load output B hole 13.3, and can communicate the shell right load hole 4.5 and the shell right oil inlet hole 4.2, or communicate the shell right load hole 4.5 and the shell oil return hole 4.4 according to the movement position of the valve core.

[0043] The working principle of the torque motor assembly: the torque motor assembly is an electric-mechanical converter, the control magnetic field generated by the coil interacts with the polarization magnetic field after the coil 9 is energized, and the electromagnetic driving force is generated on the armature 2, the armature 2 is fixedly connected with the baffle 12, the support pipe 11 and the spring pipe 10, the electromagnetic force drives the armature 2 to drive the baffle 12 to produce translational displacement.

[0044] The working principle of the flow amplification assembly: as Figure 7As shown, after the working oil enters the housing's left oil inlet 4.1, it splits into two streams. The first stream passes sequentially through the first left oil inlet hole 5.1, the left throttle hole 6.1, and the left valve core oil outlet hole 6.5, ultimately exiting the left nozzle hole 5.5. The second stream enters the second left oil inlet hole 5.2, where it is blocked by the left valve core's second shoulder 6.3. At this point, the cavity formed by the left valve core's second shoulder 6.3 and third shoulder 6.4 is empty, and thus no working oil is discharged from the housing's left load hole 4.3. When the baffle 12 moves leftward, the distance between the left nozzle 5 and the baffle 12 decreases, reducing the flow rate of oil discharged from the left nozzle hole 5.5. This increases the oil pressure within the left nozzle, pushing the left valve core 5 to slide leftward. This movement connects the housing's left load hole 4.3 with the left oil inlet hole 4.1, and the housing's left load hole 4.3 begins to discharge working oil. When the baffle 12 moves to the right, the distance between the left nozzle 5 and the baffle 12 increases, and the oil flow rate ejected from the left nozzle hole 5.5 increases, causing the oil pressure in the left nozzle to drop, pushing the left valve core 5 to slide to the right. The movement of the valve core connects the left load hole 4.3 of the housing with the housing oil return hole 4.4, and the working oil in the left load hole 4.3 of the housing is released to the oil return hole.

[0045] Similarly, Figure 7 As shown, after the working oil enters the housing's right oil inlet 4.2, it splits into two streams. The first stream passes sequentially through the first right oil inlet hole 13.1, the right throttle hole 16.1, and the right valve core oil outlet hole 16.5, ultimately exiting the right nozzle hole 13.5. The second stream, after entering the second right oil inlet hole 13.2, is blocked by the right valve core's second shoulder 16.3. At this point, no oil flows into the cavity formed by the right valve core's second shoulder 16.3 and third shoulder 16.4. Therefore, no working oil is discharged from the housing's right load hole 4.5. When the baffle 12 moves rightward, the distance between the right nozzle 13 and the baffle 12 decreases, reducing the flow rate of oil discharged from the right nozzle hole 13.5. This increases the oil pressure within the right nozzle, pushing the right valve core 16 to slide rightward. This movement of the valve core connects the housing's right load hole 4.5 with the housing's right oil inlet hole 4.2, and the housing's right load hole 4.5 begins to discharge working oil. When the baffle 12 moves to the left, the distance between the right nozzle 13 and the baffle 12 increases, and the oil flow rate ejected from the right nozzle hole 13.5 increases, causing the oil pressure in the right nozzle to drop, pushing the right valve core 16 to slide to the left. The movement of the valve core connects the right load hole 4.5 of the housing with the housing return hole 4.4, and the working oil in the right load hole 4.5 of the housing is released to the oil return hole.

[0046] The diameters of the left nozzle 5 and the right nozzle 13 are 7 mm, and the diameters of the left valve core 6 and the right valve core 16 are 4 mm, in order to achieve a small size and a small space for the servo valve.

[0047] The movement stroke of the baffle is 0.05mm, and the movement stroke of the left valve core and the right valve core is 0.5mm, so as to improve the output flow of the servo valve, and convert the small flow output at the nozzle-baffle into large flow output controlled at the spool.

[0048] The novel servo valve structure nests a cylindrical spool structure in the nozzle, not only realizes the effect of small space size and compact structure, but also converts the small flow output at the nozzle into large flow output controlled at the valve core ring surface, and realizes large flow output of the single-stage servo valve.

[0049] Finally, it should be explained that: the above examples are only used to illustrate the technical scheme of the utility model, but the protection scope of the utility model is not limited to this, any skilled person in the art can easily think of various equivalent modifications or replacements within the technical range disclosed by the utility model, and these modifications or replacements should be covered in the protection scope of the utility model.

Claims

1. A small size large flow electro-hydraulic servo valve, characterized by, It includes torque motor assembly, nozzle-baffle assembly, flow amplification assembly and shell (4); the torque motor assembly is arranged on the shell (4), and the torque motor assembly includes upper magnetic conductor (1), armature (2), lower magnetic conductor (3), coil (9), spring tube (10), support tube (11); the armature (2) is arranged between the upper magnetic conductor (1) and the lower magnetic conductor (3), the coil (9) is wound on the armature (2), the upper end of the spring tube (10) is embedded in the armature (2), the lower end is connected with the shell (4), and the support tube (11) is arranged between the spring tube (10) and the armature (2); The nozzle-baffle assembly includes left nozzle (5), baffle (12) and right nozzle (13), the baffle (12) is arranged in the shell (4), the upper end is fixedly connected with the armature (2), the lower end is arranged between the left nozzle (5) and the right nozzle (13), the left nozzle (5) includes first left oil inlet hole (5.1), second left oil inlet hole (5.2), load output A hole (5.3), left oil return hole (5.4) and left nozzle hole (5.5); the first left oil inlet hole (5.1) and the second left oil inlet hole (5.2) are connected with the shell oil inlet hole, the load output A hole (5.3) is connected with the shell left load hole, and the left oil return hole (5.4) and the left nozzle hole (5.5) are connected with the shell oil return hole; the right nozzle (13) includes first right oil inlet hole (13.1), second right oil inlet hole (13.2), load output B hole (13.3), right oil return hole (13.4) and right nozzle hole (13.5); the first right oil inlet hole (13.1) and the second right oil inlet hole (13.2) are connected with the shell oil inlet hole, the load output B hole (13.3) is connected with the shell right load hole, and the right oil return hole (13.4) and the right nozzle hole (13.5) are connected with the shell oil return hole; The flow amplification assembly includes left valve core (6), left limit block (7), left spring (8), right valve core (16), right limit block (14) and right spring (15), the left valve core (6) is slidably arranged in the left nozzle (5), and the left valve core (6) is limited by the left limit block (7) and the left spring (8) arranged in the shell; the right valve core (16) is slidably arranged in the right nozzle (13), and the right valve core (16) is limited by the right limit block (14) and the right spring (15) arranged in the shell; The left valve core (6) includes left throttle hole (6.1), left valve core first shaft shoulder (6.2), left valve core second shaft shoulder (6.3), left valve core third shaft shoulder (6.4), left valve core oil outlet hole (6.5), one end of the left valve core oil outlet hole (6.5) is communicated with the left nozzle hole (5.5), the other end is communicated with the left throttle hole (6.1), and the left throttle hole (6.1) is communicated with the first left oil inlet hole (5.1); the cavity formed by the left valve core second shaft shoulder (6.3) and the left valve core third shaft shoulder (6.4) is connected with the shell left load hole through the load output A hole (5.3), and can communicate the shell left load hole and the shell oil inlet hole, or communicate the shell left load hole and the shell oil return hole according to the movement position of the valve core; The right valve core (16) comprises a right throttle hole (16.1), a right valve core first shaft shoulder (16.2), a right valve core second shaft shoulder (16.3), a right valve core third shaft shoulder (16.4), a right valve core oil outlet hole (16.5), one end of the right valve core oil outlet hole (16.5) being communicated with the right nozzle hole (13.5), the other end being communicated with the right throttle hole (16.1), the right throttle hole (16.1) being communicated with the first right oil inlet hole (13.1); the cavity formed by the right valve core second shaft shoulder (16.3) and the right valve core third shaft shoulder (16.4) is connected with the shell right load hole through the load output B hole (13.3), and can communicate the shell right load hole and the shell oil inlet hole or communicate the shell right load hole and the shell oil return hole according to the movement position of the valve core.

2. A small size large flow electro-hydraulic servo valve according to claim 1, characterized in that, The coaxiality of the left nozzle (5) and the right nozzle (13) is 0.02mm; the coaxiality of the left nozzle (5) and the left valve core (6) is 0.02mm; the coaxiality of the right nozzle (13) and the right valve core (16) is 0.02mm.

3. A small size large flow electro-hydraulic servo valve according to claim 1, characterized in that, The distance between the left nozzle (5), the right nozzle (13) and the baffle (12) is all 0.05mm.

4. The small size large flow electro-hydraulic servo valve according to claim 1, characterized in that, The movement stroke of the left valve core (6) and the right valve core (16) is all not less than 0.5mm.

5. A small size large flow electro-hydraulic servo valve according to claim 1, characterized in that, The stiffness of the left spring (8) and the right spring (15) is determined by the oil supply pressure, the left nozzle hole and the right nozzle hole diameter; the stiffness difference of the left and right springs is not more than 1 / 10 of the stiffness of the left spring or 1 / 10 of the stiffness of the right spring.

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