Servo control structure in hydraulic field

Abstract

The problems that an existing electro-hydrostatic actuator is bloated in appearance and large in occupied space are solved. The invention provides a servo control structure in the hydraulic field. The servo control structure comprises a connecting structure used for being connected with an external hydraulic device, a rotating structure providing rotating power and a plunger pump structure. At least one mounting groove for mounting the plunger pump structure and the rotating structure is formed in the connecting structure; a plunger pump structure is fixedly arranged in the mounting groove, and the rotating structure is also fixedly mounted on the connecting structure; the rotating structure is a frameless motor and is arranged on the outer side of the plunger pump structure in a sleeving manner; a rotor in the rotating structure is fixedly connected with a rotating shaft in the plunger pump structure, and the rotating shaft rotates along with the rotor; an oil inlet and outlet communicated with the plunger pump structure is formed in each mounting groove of the connecting structure, and the oil inlets and outlets are communicated with the part, connected with an external hydraulic device, of the connecting structure; the whole system is highly integrated, and the overall size of the device is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of hydraulic control devices, in particular to a servo control structure in the field of hydraulics. BACKGROUND

[0002] An electro-hydraulic actuator (EHA) is a device unit that combines a servo motor, a bidirectional plunger pump, a control valve group and an actuator tightly, through the design of high integration of each component, not only greatly reduces the overall volume and weight of the system, but also eliminates the external pipeline connection between each structure, which is converted into an internal pipeline, has a more stable connection relationship, and further reduces the overall volume, such as the content shown in the patent with the application publication number CN115095566A. However, the servo motor and the plunger pump in the existing EHA are packaged separately, and transmission is achieved between the two by setting transmission components such as gears, and the overall shape is still relatively "bulky", which is not conducive to the miniaturization of the device as a whole, and it is also difficult to design an electro-hydraulic actuator combination that controls multiple hydraulic devices to act simultaneously. It is usually used as a single device. Therefore, a highly integrated servo control structure in the field of hydraulics is needed. SUMMARY

[0003] The purpose of the present application is to solve the problems of the prior art and provide a servo control structure in the field of hydraulics.

[0004] In order to solve the above problems, the technical scheme adopted by the present application is as follows: A servo control structure in the field of hydraulics, comprising a connecting structure for connecting external hydraulic devices, a rotating structure for providing rotating power, and a plunger pump structure; at least one mounting groove for mounting the plunger pump structure and the rotating structure is provided on the connecting structure; the plunger pump structure is fixedly arranged in the mounting groove, and the rotating structure is also fixedly mounted on the connecting structure; the rotating structure is a frameless motor, and the rotating structure is sleeved on the outside of the plunger pump structure; the rotor in the rotating structure is fixedly connected with the shaft in the plunger pump structure, and the shaft rotates with the rotor; an oil inlet and outlet in communication with the plunger pump structure is arranged in each mounting groove of the connecting structure, and the oil inlet and outlet are in communication with the part of the connecting structure connected to the external hydraulic device.

[0005] Further, the plunger pump structure comprises a rotating shaft, an oil distribution disc, a plunger, a swash plate and a plunger cavity; the plunger cavity is sleeved outside the rotating shaft and is connected with the rotating shaft by a key; a plurality of oil cavities parallel to the axis of the rotating shaft are arranged in the plunger cavity; the oil cavities are distributed at equal angles around the axis of the rotating shaft; the plunger is slidingly arranged in the oil cavity; the two ends of the oil cavity penetrate through the plunger cavity, one end of the oil cavity faces the oil distribution disc, and the other end of the oil cavity faces the swash plate; the swash plate is fixedly arranged in the mounting groove and is arranged obliquely relative to the axis of the plunger; the oil distribution disc is fixedly arranged at the bottom of the mounting groove, and an oil distribution hole is further arranged on the oil distribution disc and communicates with the chamber and the oil inlet and outlet; one end of the rotating shaft is rotatably connected with the oil distribution disc, and the other end of the rotating shaft penetrates through the plunger cavity and the swash plate and is connected with a rotating structure; the rotating shaft and the swash plate are rotatably connected.

[0006] Further, two oil distribution grooves corresponding to the two oil distribution holes are further arranged on the oil distribution disc; one oil distribution groove communicates with one oil distribution hole; the two oil distribution grooves are symmetrically arranged about the center of the circular oil distribution disc; the oil distribution groove is located on the side of the oil distribution disc close to the plunger cavity; the shape of the oil distribution groove is arc-shaped and corresponds to the distribution position of the chamber on the plunger cavity.

[0007] Further, a protruding key is arranged outside the rotating shaft and is connected with the plunger cavity by a key, and a key groove corresponding to the protruding key is arranged inside the plunger cavity; one end of the key groove communicates with the end of the plunger cavity close to the oil distribution disc; the other end of the key groove extends along the axis direction of the plunger cavity for a certain length; a spring is further arranged inside the plunger cavity, the spring is sleeved outside the rotating shaft, one end of the spring abuts against the protruding key outside the rotating shaft, and the other end of the spring abuts against the plunger cavity.

[0008] Further, a ring-shaped clamping ring for abutting against the spring is arranged in the through hole of the rotating shaft inside the plunger cavity, the clamping ring is embedded in the annular groove of the inner wall of the plunger cavity, and the clamping ring is located at the end of the plunger cavity close to the oil distribution disc; the other end of the spring abuts against the protruding key outside the rotating shaft through the annular piece.

[0009] Further, one end of the plunger close to the oil distribution disc is arranged as a plane; the other end of the plunger close to the swash plate is arranged as an umbrella surface matching the slope of the swash plate.

[0010] Further, the oil cavity arranged in the plunger cavity is arranged as a cylindrical hole matching the shape of the plunger on the side close to the swash plate; the side of the plunger cavity close to the oil distribution disc is arranged as a waist-shaped hole with a smaller cross section than the plunger, and the waist-shaped hole communicates with the cylindrical hole; the length direction of the waist-shaped hole faces the tangential direction of the plunger cavity.

[0011] Further, an oil storage groove communicating with one of the oil inlets and outlets at the bottom of the mounting groove is further arranged in the connecting structure; the two oil inlets and outlets at the bottom of the mounting groove are further connected to the part where the connecting structure is connected with the external hydraulic device through the pipeline inside the connecting structure.

[0012] Further, the oil liquid storage tank comprises two cylindrical storage cavities; two ends of the two cylindrical storage cavities are communicated with each other.

[0013] Further, the two cylindrical storage cavities are different in diameter, and the diameter of one storage cavity is smaller than that of the other storage cavity.

[0014] The present application has the following advantages: By directly connecting the rotating structure and the rotating shaft in the plunger pump structure, and by sleeving the frameless motor of the rotating structure outside the plunger pump structure, the whole system is highly integrated, and the overall volume of the device is reduced. By arranging the spring in the plunger pump structure, the radial component force transmitted by the swash plate is balanced, and the plunger cavity can stably rotate with the rotating shaft. By arranging the angle sensor and the rotating speed sensor, the rotating angle of the external hydraulic device is associated with the rotating speed of the rotating shaft, and closed-loop precise control is realized. By arranging the pipeline inside the connecting structure and connecting the pipeline with the plunger pump structures in different mounting grooves, multiple plunger pumps are arranged simultaneously, there is no external pipeline, the connection is stable, the structure is simple, and the overall volume is small. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 It is a schematic diagram of the overall structure of embodiment 1; Figure 2 It is an exploded view of the overall structure of embodiment 1; Figure 3 It is a sectional view of the overall structure of embodiment 1; Figure 4 It is another angle of the sectional view of the overall structure of embodiment 1; Figure 5 It is a schematic diagram of the mounting groove in the connecting structure of embodiment 1; Figure 6 It is an exploded view of the rotating structure and the plunger pump structure of embodiment 1; Figure 7 It is a sectional view of the rotating structure and the plunger pump structure of embodiment 1; Figure 8 It is a schematic diagram of the oil distribution disc of embodiment 1; Figure 9 It is a schematic diagram of the plunger cavity of embodiment 1; Figure 10 It is a sectional view of the plunger cavity of embodiment 1; Figure 11 It is a perspective view of the pipeline inside the overall structure of embodiment 1.

[0016] Figure labeling: 1. Connection structure; 11. Mounting groove; 12. Oil storage tank; 13. Oil inlet / outlet; 14. Positioning tube; 2. Rotating structure; 21. Detection circuit; 3. Plunger pump structure; 31. Oil distribution plate; 311. Oil distribution hole; 312. Oil distribution groove; 32. Plunger; 33. Swashplate; 34. Plunger cavity; 341. Keyway; 342. Oil cavity; 343. Annular groove; 35. Rotating shaft; 351. Protruding key; 36. Spring; 37. Snap ring; 38. Annular plate; 39. Speed ​​sensor. Detailed Implementation

[0017] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, unless otherwise specified, the following embodiments and features described therein can be combined with each other.

[0018] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the figures only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0019] Example 1: like Figures 1-11 As shown, a servo control structure for hydraulic applications includes a connecting structure 1 for connecting to an external hydraulic device, a rotating structure 2 for providing rotational power, and a piston pump structure 3. The connecting structure 1 has at least one mounting groove 11 for mounting the piston pump structure 3 and the rotating structure 2; in this example, the connecting structure 1 has four mounting grooves 11. The piston pump structure 3 is fixedly mounted within each mounting groove 11, and the rotating structure 2 is also fixedly mounted on the connecting structure 1. The rotating structure 2 is a frameless motor, and it is sleeved on the outside of the piston pump structure 3, specifically at the edge of the opening of the mounting groove 11 in this example. The rotor in the rotating structure 2 is fixedly connected to the rotating shaft 35 in the piston pump structure 3. The rotating shaft 35 rotates with the rotor. In this way, the rotating structure 2 and the piston pump structure 3 can be directly associated and nested together, which greatly reduces the overall size. Each mounting slot 11 of the connecting structure 1 is provided with an oil inlet / outlet 13 that communicates with the piston pump structure 3. The oil inlet / outlet 13 is connected to the part of the connecting structure 1 that connects to the external hydraulic device. Through the internal pipeline of the connecting structure 1, the piston pump structure 3 is connected to the external device that needs to be hydraulically driven, so as to realize the purpose of hydraulically controlling the action of the external device.

[0020] The plunger pump structure 3 comprises a rotating shaft 35, an oil distribution disc 31, a plunger 32, a swash plate 33 and a plunger cavity 34; the plunger cavity 34 is sleeved outside the rotating shaft 35 and is in key connection with the rotating shaft 35, and rotates together with the rotating shaft 35; a plurality of oil cavities 342 parallel to the axis of the rotating shaft 35 are arranged in the plunger cavity 34; the oil cavities 342 are distributed at equal angles around the axis of the rotating shaft 35; the plunger 32 is slidingly arranged in the oil cavity 342; when the plunger 32 slides, hydraulic oil is extruded or sucked into the corresponding oil cavity 342 through the oil distribution disc 31, so as to control the pressure of the hydraulic oil in the oil inlet and outlet 13; the two ends of the oil cavity 342 respectively penetrate through the plunger cavity 34, one end of the oil cavity 342 faces the oil distribution disc 31, and the other end of the oil cavity 342 faces the swash plate 33; the swash plate 33 is fixedly arranged in the mounting groove 11, and the swash plate 33 is arranged obliquely relative to the axis of the plunger 32; in this way, when the plunger cavity 34 rotates, the plunger 32 is pushed towards the swash plate 33 due to the pressure of the hydraulic oil stored in the oil cavity 342, and the position of the plunger 32 in different oil cavities 342 is different in cooperation with the inclined surface on the swash plate 33; in addition, the plunger cavity 34 rotates rapidly together with the rotating shaft 35, so as to control the pressure of the hydraulic oil in the oil cavities 342 on both sides corresponding to the inclined surface of the swash plate 33 to be different, thereby controlling the hydraulic pressures of the two oil inlet and outlet 13 parts at the bottom of the mounting groove 11 to be different, and driving the external hydraulic device. The oil distribution disc 31 is fixedly arranged at the bottom of the mounting groove 11, and the oil distribution disc 31 is further provided with oil distribution holes 311 communicating with the oil distribution chamber and the oil inlet and outlet 13; one end of the rotating shaft 35 is in rotary connection with the oil distribution disc 31, and the other end of the rotating shaft 35 penetrates through the plunger cavity 34 and the swash plate 33 and is connected with the rotating structure 2; the rotating shaft 35 is in rotary cooperation with the swash plate 33; it should be noted that in this example, bearings are arranged between the rotating shaft 35 and the oil distribution disc 31 and between the rotating shaft 35 and the swash plate 33, so as to realize the rotary connection therebetween. In this example, the mounting groove 11 is further provided with a cylindrical positioning pipe 14 protruding outward, the plunger cavity 34 is rotatably arranged in the positioning pipe 14, and the end of the positioning pipe 14 is fixedly connected with the swash plate 33 through bolts, so as to fix the swash plate 33.

[0021] The oil distribution disc 31 is further provided with two oil distribution grooves 312 corresponding to the two oil distribution holes 311 respectively; one oil distribution groove 312 communicates with one oil distribution hole 311; the two oil distribution grooves 312 are symmetrically arranged about the center of the circular oil distribution disc 31; the oil distribution groove 312 is located on one side of the oil distribution disc 31 close to the plunger cavity 34; the shape of the oil distribution groove 312 is arc-shaped, and corresponds to the distribution position of the cavities on the plunger cavity 34; in this example, nine oil cavities 342 are arranged on the plunger cavity 34, and each oil distribution groove 312 communicates with at most four oil cavities 342.

[0022] The outer side of the rotating shaft 35 is provided with a key 351 which is connected with the column cavity 34, and the inside of the column cavity 34 is provided with a key groove 341 which corresponds to the key 351; one end of the key groove 341 is communicated to the end of the column cavity 34 which is close to the oil distribution disc 31; the other end of the key groove 341 extends along the axial direction of the column cavity 34 for a certain length; the inside of the column cavity 34 is further provided with a spring 36 which is sleeved on the outer side of the rotating shaft 35, one end of the spring 36 abuts against the key 351 on the outer side of the rotating shaft 35, and the other end of the spring 36 abuts against the column cavity 34; the inside of the column cavity 34 which corresponds to the through hole of the rotating shaft 35 is provided with an annular clamping ring 37 which is used to abut against the spring 36, the clamping ring 37 is embedded in the annular groove 343 on the inner wall of the column cavity 34, and the clamping ring 37 is located at the end of the column cavity 34 which is close to the oil distribution disc 31; the other end of the spring 36 abuts against the key 351 on the outer side of the rotating shaft 35 through an annular piece 38. In this case, three key grooves 341 are provided in the inside of the column cavity 34, when the clamping ring 37 is installed, the clamping ring 37 is pushed into the column cavity 34 by means of the position of the key groove 341, when it is pushed to the annular groove 343, the clamping ring 37 is turned over and clamped in the annular groove 343; it should be noted that in order to facilitate the turning over of the clamping ring 37, in this case, the side wall of the annular groove 343 which is away from the oil distribution disc 31 is provided as an inclined circular cone-shaped inclined surface. In some other embodiments, a protrusion which corresponds to the key groove 341 can also be provided on the edge of the clamping ring 37, when the protrusion on the clamping ring 37 corresponds to the key groove 341 in the inside of the column cavity 34, the clamping ring 37 can be installed into the inside of the column cavity 34 until the clamping ring 37 is pushed to the position which corresponds to the annular groove 343, the protrusion on the clamping ring 37 is turned into the annular groove 343 by turning the clamping ring 37; in order to further fix the clamping ring 37, a groove which corresponds to the protrusion on the clamping ring 37 is further provided on the side wall of the annular groove 343 which is close to the oil distribution disc 31. The spring 36 is provided to balance a part of the radial force which is transmitted by the swash plate 33 to the plug column 32 and the column cavity 34 in the radial direction, so that the rotating process of the column cavity 34 is more stable.

[0023] The end of the plug column 32 which is close to the oil distribution disc 31 is provided as a plane; the end of the plug column 32 which is close to the swash plate 33 is provided as an umbrella surface which matches the slope of the swash plate 33, so as to increase the contact area between the plug column 32 and the swash plate 33, reduce the pressure, and reduce the extrusion damage of the plug column 32 when it is extruded by the swash plate 33.

[0024] The oil cavity 342 which is provided in the column cavity 34 is provided as a cylindrical hole which matches the shape of the plug column 32 on the side which is close to the swash plate 33; the side of the column cavity 34 which is close to the oil distribution disc 31 is provided as a waist-shaped hole which has a smaller cross section than the plug column 32, and the waist-shaped hole is communicated with the cylindrical hole; the length direction of the waist-shaped hole is towards the tangential direction of the column cavity 34; in this way, it can be avoided that the plug column 32 is taken out of the oil cavity 342 in the column cavity 34 from the other side.

[0025] The connecting structure 1 is further provided with an oil storage groove 12 in communication with one of the oil inlets and outlets 13 at the bottom of the mounting groove 11; the other two oil inlets and outlets 13 at the bottom of the mounting groove 11 are respectively connected to the connecting position of the connecting structure 1 and the external hydraulic device through the pipeline inside the connecting structure 1; the oil storage groove 12 comprises two cylindrical storage cavities; the two ends of the two cylindrical storage cavities are in communication with each other; the diameters of the two cylindrical storage cavities are different, and the diameter of one of the storage cavities is smaller than that of the other storage cavity; the oil storage groove 12 can help to adapt to the change of the oil capacity within a certain range, and ensure the stable operation of the whole system.

[0026] The connecting structure 1 is provided with a rotating ring connected with the external rotating hydraulic device, and an angle sensor is arranged in the rotating ring; a rotating speed sensor 39 is arranged on the rotating shaft 35 of the plunger pump structure 3, and a detection circuit 21 corresponding to the rotating speed sensor 39 is arranged in the frameless motor of the rotating structure 2; by measuring the rotating speed of the rotating shaft 35 and the rotating angle of the external rotating hydraulic device, the correlation closed-loop control of the two can be realized, and stable control can be realized The above description is only one specific example of the present application and does not constitute any limitation on the present application. Obviously, for those skilled in the art, after understanding the content and principles of the present application, various modifications and changes in form and details can be made without departing from the principles and structures of the present application, but these modifications and changes based on the idea of the present application are still within the protection scope of the claims of the present application.

Claims

1. A hydraulic servo control structure characterized by comprising: The utility model provides a kind of hydraulic pump, including the connecting structure (1) for connecting external hydraulic device, the rotating structure (2) for providing rotating power and plunger pump structure (3);At least one mounting groove (11) for installing plunger pump structure (3) and rotating structure (2) is provided on the connecting structure (1);Plunger pump structure (3) is fixedly arranged in mounting groove (11), and rotating structure (2) is also fixedly installed on connecting structure (1);Rotating structure (2) is frameless motor, and rotating structure (2) is sleeved and arranged on the outside of plunger pump structure (3);Rotor in rotating structure (2) is fixedly connected with shaft (35) in plunger pump structure (3), and shaft (35) rotates with rotor;Oil inlet and outlet (13) in communication with plunger pump structure (3) is respectively arranged in each mounting groove (11) of connecting structure (1), and oil inlet and outlet (13) is in communication with the part of connecting structure (1) for connecting external hydraulic device.

2. The hydraulic servo control structure according to claim 1, wherein The plunger pump structure (3) includes shaft (35), and further includes oil distribution disc (31), plug column (32), swash plate (33) and column cavity (34);Wherein column cavity (34) is sleeved on the outside of shaft (35), and is keyed with shaft (35);A plurality of oil chambers (342) parallel to the axis of shaft (35) are provided in column cavity (34);Oil chamber (342) is distributed at equal angles around the axis of shaft (35);Plug column (32) is slidably arranged in oil chamber (342);Two ends of oil chamber (342) respectively penetrate column cavity (34), one end of oil chamber (342) faces oil distribution disc (31), and the other end of oil chamber (342) faces swash plate (33);Swash plate (33) is fixedly arranged in mounting groove (11), and is arranged obliquely relative to the axis of plug column (32);Oil distribution disc (31) is fixedly arranged at the bottom of mounting groove (11), and further provided with oil distribution hole (311) in communication with chamber and oil inlet and outlet (13) on oil distribution disc (31);One end of shaft (35) is rotatably connected with oil distribution disc (31), and the other end of shaft (35) penetrates column cavity (34) and swash plate (33) and is connected with rotating structure (2);Shaft (35) and swash plate (33) are rotatably connected.

3. The hydraulic servo control structure according to claim 2, wherein Two oil distribution grooves (312) corresponding to two oil distribution holes (311) are further provided on the oil distribution disc (31);One oil distribution groove (312) is in communication with one oil distribution hole (311);Two oil distribution grooves (312) are symmetrically arranged about the center of the circular oil distribution disc (31);Oil distribution groove (312) is located on one side of oil distribution disc (31) close to column cavity (34);The shape of oil distribution groove (312) is arc, and corresponds to the distribution position of chamber on column cavity (34).

4. The hydraulic servo control structure according to claim 2, wherein The outer side of the rotating shaft (35) is provided with a key (351) connected with the column cavity (34), and the column cavity (34) is provided with a key groove (341) corresponding to the key (351) inside; one end of the key groove (341) is communicated to the end of the column cavity (34) near the oil distribution disc (31); the other end of the key groove (341) extends along the axis direction of the column cavity (34) for a certain length; the column cavity (34) is further provided with a spring (36) inside, the spring (36) is sleeved on the outer side of the rotating shaft (35), one end of the spring (36) abuts against the key (351) on the outer side of the rotating shaft (35), and the other end of the spring (36) abuts against the column cavity (34).

5. The hydraulic servo control structure according to claim 4, wherein The column cavity (34) is provided with an annular clamping ring (37) for abutting against the spring (36) inside the through hole of the rotating shaft (35), the clamping ring (37) is embedded in the annular groove of the inner wall of the column cavity (34), and the clamping ring (37) is located at one end of the column cavity (34) near the oil distribution disc (31); the other end of the spring (36) abuts against the key (351) on the outer side of the rotating shaft (35) through the annular sheet (38).

6. The hydraulic servo control structure according to claim 2, wherein One end of the plug column (32) near the oil distribution disc (31) is provided as a plane; one end of the plug column (32) near the swash plate (33) is provided as an umbrella surface matching the slope of the swash plate (33).

7. The hydraulic servo control structure according to claim 6, wherein The oil cavity (342) provided in the column cavity (34) is provided as a cylindrical hole matching the outer shape of the plug column (32) on the side near the swash plate (33); the side of the column cavity (34) near the oil distribution disc (31) is provided as a waist-shaped hole with a smaller cross section than the plug column (32), and the waist-shaped hole is communicated with the cylindrical hole; the length direction of the waist-shaped hole is towards the tangential direction of the column cavity (34).

8. The hydraulic servo control structure according to claim 1, wherein The connecting structure (1) is further provided with an oil storage groove (12) communicated with one of the oil inlets and outlets (13) at the bottom of the mounting groove (11); the other two oil inlets and outlets (13) at the bottom of the mounting groove (11) are further connected to the part of the connecting structure (1) connected with the external hydraulic device through the pipeline inside the connecting structure (1).

9. The hydraulic servo control structure according to claim 8, wherein The oil storage groove (12) comprises two cylindrical storage cavities; the two ends of the two cylindrical storage cavities are communicated with each other.

10. The hydraulic servo control structure according to claim 9, wherein The diameters of the two cylindrical storage cavities are different, and the diameter of one storage cavity is smaller than that of the other storage cavity.

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