Compact actuating device

Abstract

The utility model relates to the technical field of electric cylinders, in particular to a compact actuating device which comprises a cylinder body and a piston rod, and the piston rod is inserted into the cylinder body and moves in the axial direction of the cylinder body. The screw rod is rotationally arranged in the cylinder body; the nut is in threaded connection with the lead screw and moves in the axial direction of the cylinder body; one end of the piston is sleeved on the nut, and the other end of the piston is connected with the piston rod; and the anti-rotation ring is coaxially arranged on the nut in a sleeving mode and located on the side, away from the piston rod, of the piston, and the anti-rotation ring is used for limiting relative rotation between the nut and the cylinder body. According to the actuating device, it is guaranteed that the piston structure in the actuating device is compact, the force output stroke of the actuating device is long, and meanwhile reliable rotation prevention is guaranteed.

Description

Technical Field

[0001] The present application relates to the technical field of electric cylinders, and in particular to a compact actuating device. Background Art

[0002] As a commonly used linear drive device, the electric push rod has gradually occupied the primary position of linear drive devices with its characteristics of high speed, quietness and high precision. The core components of the electric cylinder include motor, reducer and screw. Different configurations of these parts can be selected according to different output and speed requirements.

[0003] In the existing electric cylinder barrel, the piston is connected between the nut and the piston rod. In order to improve the stability of the piston rod when it is extended, an anti-rotation strip is provided on the piston to provide guidance for the linear movement of the piston along the cylinder barrel. However, such a setting causes the axial length of the piston part to be too long, thereby occupying more of the piston rod's moving stroke, resulting in a shorter piston rod stroke margin. Utility Model Content

[0004] The utility model aims to solve one of the problems existing in the background technology.

[0005] To this end, the utility model provides a compact actuating device.

[0006] The technical solution adopted by the utility model to solve its technical problems is:

[0007] A compact actuating device comprising:

[0008] Cylinder, and

[0009] A piston rod, which is inserted into the cylinder body and moves along the axial direction of the cylinder body;

[0010] A screw rod, the screw rod is rotatably arranged in the cylinder body;

[0011] A nut, the nut being threadedly connected to the screw rod and moving along the axial direction of the cylinder body;

[0012] A piston, one end of which is sleeved on the nut and the other end of which is connected to the piston rod;

[0013] By adopting the above technical solution, one end of the piston is sleeved on the nut, so that the overall axial length of the piston and the nut is relatively short, and the length of the piston rod is relatively increased. When the piston moves linearly in the cylinder body, the travel margin of the piston rod is increased.

[0014] Furthermore, the other end of the piston is inserted into the piston rod and threadedly connected to the piston rod.

[0015] Furthermore, it also includes an anti-rotation ring, which is coaxially sleeved on the nut and located on the side of the piston away from the piston rod. The anti-rotation ring is used to limit the relative rotation between the nut and the cylinder body.

[0016] Furthermore, a protrusion is provided on the inner side wall of the anti-rotation ring, and a first limiting surface is provided on the nut. The first limiting surface is parallel to the axial direction of the nut, and the protrusion is in contact with the first limiting surface.

[0017] By adopting the above technical solution, the relative rotation between the anti-rotation ring and the nut is limited through the cooperation between the protrusion and the first limiting surface, and the installation between the anti-rotation ring and the nut is pre-positioned, thereby facilitating the installation of the anti-rotation ring.

[0018] Furthermore, a second limiting surface is provided on the nut, the second limiting surface is perpendicular to the axial direction of the nut, and the protrusion is in contact with the second limiting surface.

[0019] By adopting the above technical solution, the axial position of the anti-rotation ring on the nut is limited through the cooperation between the protrusion and the second limiting surface, and the installation between the anti-rotation ring and the nut is pre-positioned, thereby facilitating the installation of the anti-rotation ring.

[0020] Furthermore, a first positioning surface is provided on the piston, and a second positioning surface is provided on the inner side wall of the piston rod, and the first positioning surface is in contact with the second positioning surface.

[0021] Furthermore, the piston rod is sleeved on the screw rod, and a support ring bearing is arranged between one end of the screw rod located inside the piston rod and the piston rod.

[0022] Furthermore, a second retaining ring is sleeved on the screw rod, and the second retaining ring is used to limit the movement of the support ring bearing along the axial direction of the screw rod.

[0023] Furthermore, a connecting assembly is provided between the cylinder body and the driving mechanism, the connecting assembly comprises a connecting front flange and a connecting rear flange, the connecting rear flange is rigidly connected to the driving mechanism, the connecting front flange is rigidly connected to the cylinder body, and the connecting front flange is threadedly connected to the connecting rear flange.

[0024] Furthermore, the front connection flange and the rear connection flange are integrally arranged.

[0025] Furthermore, a bearing seat and a bearing cover are provided on the inner side of the cylinder end, the bearing seat and the bearing cover are embedded in the inner wall of the cylinder, the bearing seat is arranged close to the driving mechanism, the screw rod passes through the bearing seat and the bearing cover and is rotatably connected to the bearing seat through the bearing.

[0026] Furthermore, the end of the screw rod is transmission-connected to the driving mechanism via a coupling, and the coupling presses the bearing cover and the bearing tightly against the cylinder body.

[0027] Furthermore, a front end cover is connected to one end of the cylinder body away from the driving mechanism, and the piston rod can extend out of the cylinder body through the front end cover. The front end cover is provided with an inner hole for the piston rod to pass through, and a hole groove is opened on the side wall of the inner hole, and the hole groove is used to install a sleeve and a dust ring.

[0028] Furthermore, a sealing ring groove for installing a sealing ring is opened on the outer circle of the front end cover, and the front end cover is clamped and limited in the cylinder body by a first retaining ring.

[0029] Furthermore, the piston is connected to a sensing component, and an induction switch is provided on the inner wall of the cylinder body, and the induction switch cooperates with the sensor induction.

[0030] The beneficial effect of the utility model is that, by sleeve-mounting one end of the piston on the nut and inserting the other end into the piston rod, and arranging the anti-rotation ring on the nut and on the rear side of the piston, the axial length of the piston and the nut as a whole is relatively short, and the length of the piston rod is relatively increased. When the piston moves linearly in the cylinder body, the stroke margin of the piston rod is increased, and this arrangement makes the structure of the actuator device more compact, which is convenient for saving the installation space inside the actuator device, thereby increasing the output stroke of the actuator device. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0032] Figure 1 It is a structural schematic diagram of an electric cylinder in the prior art.

[0033] Figure 2 It is a structural schematic diagram of a compact actuating device in the utility model.

[0034] Figure 3 It is used to reflect Figure 2 KK-axis cross-sectional view showing the positional relationship between the middle anti-rotation ring and the nut.

[0035] Figure 4 It is a structural schematic diagram of the positional relationship between the screw rod and the nut in the utility model.

[0036] Figure 5 It is a structural schematic diagram of the anti-rotation circle in the utility model.

[0037] Figure 6 It is used to reflect Figure 2 Enlarged view of part A showing the positional relationship between the middle piston and the piston rod.

[0038] Figure 7It is used to reflect Figure 2 Enlarged view of section B at the right end of the middle screw.

[0039] Figure 8 It is used to reflect Figure 2 Enlarged view of part C showing the positional relationship between the middle piston and the mounting groove.

[0040] In the figure: 1. cylinder body; 10. front end cover; 11. sleeve; 12. dust ring; 13. sealing ring; 14. first retaining ring; 2. piston assembly; 20. piston; 21. piston rod; 22. anti-rotation ring; 23. rod head; 24. mounting groove; 25. knife back groove; 26. first positioning surface; 27. second positioning surface; 28. bump; 3. actuating mechanism; 30. screw rod; 31. nut; 32. first limiting surface; 33. second retaining ring; 34. optical axis; 35. slot; 36. support ring bearing; 37. second limiting surface; 4. driving mechanism; 5. bearing seat; 6. bearing pressure cover; 7. connecting front flange; 8. connecting rear flange; 9. coupling. DETAILED DESCRIPTION

[0041] Now the utility model is further described in detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, which only illustrate the basic structure of the utility model in a schematic manner, and therefore only show the components related to the utility model.

[0042] In the description of the present utility model, it is necessary to understand that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, features defined as "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present utility model, unless otherwise specified, "multiple" means two or more.

[0043] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0044] Reference Figure 1 In the electric cylinder in the prior art, a screw rod 30 and a nut 31 are provided in the cylinder body 1, and the nut 31 is threadedly connected to the screw rod 30. Specifically, the nut 31 is sleeved on the screw rod 30, and a spiral roller is provided between the nut 31 and the screw rod 30. Balls are provided in the spiral roller. The nut 31 moves axially along the cylinder body 1 under the rotation of the screw rod 30. The nut 31 is connected to the piston rod 21 through the piston 20. The piston 20 and the nut 31 move axially along the cylinder body 1 together. When the overall length of the piston 20 and the nut 31 is long, the moving stroke of the piston rod 21 is short.

[0045] Reference Figure 2-8 A compact actuating device comprises a cylinder body 1, a piston assembly 2, an actuating mechanism 3 and a driving mechanism 4.

[0046] The actuating mechanism 3 includes a screw rod 30 and a nut 31. The screw rod 30 is coaxially rotatably arranged in the cylinder body 1. The nut 31 and the cylinder body 1 are slidably matched along the axial direction of the cylinder body 1. The piston assembly 2 includes a piston 20 and a piston rod 21. The piston 20 is connected to the nut 31. The piston rod 21 is connected to the piston 20. The piston rod 21 is telescopically movable along the axial direction of the cylinder body 1.

[0047] In this embodiment, the description is made with the direction in which the piston rod 21 extends being the right side.

[0048] It should be noted that a first limiting surface 32 and a second limiting surface 37 are provided at the left end of the nut 31. The first limiting surface 32 is parallel to the axial direction of the nut 31. The second limiting surface 37 is provided on the side of the first limiting surface 32 close to the piston 20 and is perpendicular to the axial direction of the nut 31. A protrusion 28 is provided on the inner wall of the anti-rotation ring 22. When the anti-rotation ring 22 is sleeved on the left end of the nut 31, the first limiting surface 32 and the second limiting surface 37 are fitted with the protrusion, thereby limiting the relative rotation and axial position between the anti-rotation ring 22 and the nut 31, and pre-positioning the installation between the anti-rotation ring 22 and the nut 31, thereby facilitating the installation of the anti-rotation ring 22.

[0049] The left end of the piston 20 is coaxially sleeved on the right end of the nut 31 , and the anti-rotation ring 22 and the part of the piston 20 sleeved on the nut 31 are fixedly connected to the nut 31 by screws.

[0050] The piston 20 is sleeved on the nut 31, and the anti-rotation ring 22 is set on the nut 31 and on the rear side of the piston 20, so that the overall axial length of the piston 20 and the nut 31 is relatively short, and the length of the piston rod 21 is relatively increased. When the piston 20 moves linearly in the cylinder body 1, the travel margin of the piston rod 21 is increased.

[0051] Specifically, the outer ring of the anti-rotation ring 22 is provided with a plurality of bosses, and the inner wall of the cylinder body 1 is provided with a porous inner groove, and the bosses are engaged with the porous inner groove to prevent the nut 31 and the cylinder body 1 from rotating.

[0052] A thread is provided on the outer wall of the right end of the piston 20, and the piston rod 21 is coaxially sleeved on the right end of the screw rod 30 and the right end of the piston 20 and is threadedly connected to the piston rod 21, wherein a first positioning surface 26 is provided on the left side of the backing groove 25 at the left end of the external thread at the right end of the piston 20. When the piston rod 21 is tightened into place, it can be positioned by the second positioning surface 27 on the inner wall of the piston rod 21 and the first positioning surface 26 on the piston 20 to improve the coaxiality.

[0053] The right end of the screw rod 30 is provided with an optical axis portion 34 and a slot 35, the slot 35 is located on the right side of the optical axis portion 34, the outer wall of the optical axis portion 34 of the screw rod 30 is smooth, and a support ring bearing 36 is sleeved on the optical axis portion 34. The screw rod 30 is rotatably connected to the inner wall of the piston rod 21 through the support ring bearing 36, and the support ring bearing 36 is made of self-lubricating material, such as PTFE+CU, and the support ring bearing 36 has multiple grooves on its circumference. The support ring bearing 36 is limited by the second retaining ring 33 to reduce the possibility of the support ring bearing 36 moving along the axial direction of the screw rod 30. The inner ring of the second retaining ring 33 is embedded in the slot 35, and the left side of the second retaining ring 33 abuts against the support ring bearing 36. The left end of the screw rod 30 is transmission-connected to the driving mechanism 4.

[0054] The right end of the piston rod 21 is threadedly connected with a rod head 23. Specifically, a threaded hole is provided at the right end of the piston rod 21, and the thread on the inner wall of the threaded hole is matched with the outer thread on the rod head 23. The right end of the cylinder body 1 is connected with a front end cover 10, and the rod head 23 passes through the front end cover 10. A hole groove is opened on the side wall of the inner hole for the rod head 23 to pass through the front end cover 10, which is used to install a self-lubricating sleeve 11 and a dust ring 12. A sealing ring groove is opened on the outer circle of the front end cover 10, which is used to install a sealing ring 13 for waterproofing and dustproofing. The front end cover 10 is clamped and limited in the cylinder body 1 by a first retaining ring 14.

[0055] A connecting assembly is arranged between the left end of the cylinder body 1 and the driving mechanism 4, and the connecting assembly includes a connecting front flange 7, a connecting rear flange 8, a bearing seat 5, and a bearing cover 6. The connecting rear flange 8 is rigidly connected to the driving mechanism 4, and the connecting front flange 7 is rigidly connected to the cylinder body 1. The connecting front flange 7 is threadedly connected to the side of the connecting rear flange 8 away from the driving mechanism 4. In other embodiments, the connecting front flange 7 and the connecting rear flange 8 can also be integrally formed as a whole flange part.

[0056] The bearing seat 5 and the bearing cover 6 are coaxially embedded on the inner wall of the cylinder body 1. The inner wall of the cylinder body 1 is provided with a receiving groove for accommodating the bearing cover 6 and the bearing seat 5. The bearing cover 6 is arranged on the side of the bearing seat 5 close to the inside of the cylinder body 1, and the bearing seat 5 is arranged close to the driving mechanism 4. The side of the bearing seat 5 away from the bearing cover 6 protrudes from the end of the cylinder body 1 and is embedded on the inner side of the connecting front flange 7. A bearing is connected between the bearing seat 5 and the bearing cover 6. The screw rod 30 passes through the bearing seat 5, the bearing cover 6 and is transmission-connected with the driving mechanism 4. The screw rod 30 is rotationally connected to the bearing seat 5 through the bearing, and the screw rod 30 and the bearing seat 5 rotate relative to each other. The bearing seat 5 and the bearing cover 6 are both kept fixed between the cylinder body 1, and the connecting front flange 7 is connected to the bearing seat 5.

[0057] The bearing seat 5 and the bearing cover 6 are embedded in the cylinder body 1, so that the structure of the actuator is more compact. The bearing cover 6 is limited by the coupling 9 to improve the stability of the installation, so that the screw rod 30 can rotate stably.

[0058] It should be noted that the left end of the screw rod 30 is also provided with an optical axis portion 34, and the left end of the screw rod 30 is provided with an external thread, and the external thread is arranged on the left side of the optical axis portion 34. The left end of the screw rod 30 is threadedly connected with a coupling 9 through the external thread, and the bearing cover 6, the bearing, and the bearing seat 5 are all sleeved on the screw rod 30. After the coupling 9 is threadedly connected to the screw rod 30, the right end of the coupling 9 is against the bearing, and the bearing and the bearing cover 6 are pressed tightly in the cylinder body 1.

[0059] The outer wall of the piston 20 is provided with a mounting groove 24, and a sensing member is provided in the mounting groove 24. The sensing member can be a rubber magnetic strip. The inner wall of the cylinder body 1 is provided with a groove for installing a sensing switch. The form of the sensing member is not limited. The sensing member and the sensing switch are inductively matched. The sensing switch can be a magnetic induction switch. By adding the magnetic induction switch, the travel displacement of the actuator can be timely controlled. Because of the high precision requirement, the driving mechanism 4 can be a servo motor, a stepping motor or a stepping motor with an encoder.

[0060] In summary, the present application arranges one end of the piston 20 on the nut 31 and the other end in the piston rod 21, and arranges the anti-rotation ring 22 on the nut 31 and on the rear side of the piston 20, so that the overall axial length of the piston 20 and the nut 31 is relatively short, and the length of the piston rod 21 is relatively increased. When the piston 20 moves linearly in the cylinder body 1, the travel margin of the piston rod 21 is increased, and this arrangement makes the structure of the actuator more compact, which is convenient for saving the installation space inside the actuator, thereby increasing the output stroke of the actuator.

[0061] The bearing seat 5 and the bearing cover 6 are embedded in the cylinder body 1, so that the structure of the actuator is more compact. The bearing cover 6 is limited by the coupling 9 to improve the stability of the installation, so that the screw rod 30 can rotate stably.

[0062] Based on the above ideal embodiments of the utility model, the relevant staff can make various changes and modifications without departing from the technical concept of the utility model through the above description. The technical scope of the utility model is not limited to the content of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A compact actuating device, characterized in that: include, a cylinder body (1), and A piston rod (21), wherein the piston rod (21) is inserted into the cylinder body (1) and moves along the axial direction of the cylinder body (1); A screw rod (30), the screw rod (30) being rotatably disposed in the cylinder body (1); A nut (31), wherein the nut (31) is threadedly connected to the screw rod (30) and moves along the axial direction of the cylinder body (1); A piston (20), one end of the piston (20) is sleeved on the nut (31), and the other end is connected to the piston rod (21).

2. The compact actuating device according to claim 1, characterized in that The other end of the piston (20) is inserted into the piston rod (21) and is threadedly connected to the piston rod (21).

3. The compact actuation device according to claim 1, characterized in that It also includes an anti-rotation ring (22), which is coaxially sleeved on the nut (31) and located on the side of the piston (20) away from the piston rod (21). The anti-rotation ring (22) is used to limit the relative rotation between the nut (31) and the cylinder body (1).

4. The compact actuating device according to claim 3, characterized in that A protrusion (28) is provided on the inner side wall of the anti-rotation ring (22), and a first limiting surface (32) is provided on the nut (31). The first limiting surface (32) and the axial direction of the nut (31) are parallel to each other, and the protrusion (28) is in contact with the first limiting surface (32).

5. The compact actuating device according to claim 4, characterized in that The nut (31) is provided with a second limiting surface (37), the second limiting surface (37) and the axial direction of the nut (31) are perpendicular to each other, and the protrusion (28) is in contact with the second limiting surface (37).

6. The compact actuation device according to claim 1, characterized in that The piston (20) is provided with a first positioning surface (26), and the inner side wall of the piston rod (21) is provided with a second positioning surface (27), and the first positioning surface (26) is in contact with the second positioning surface (27).

7. The compact actuation device according to claim 1, characterized in that: The piston rod (21) is sleeved on the screw rod (30), and a support ring bearing (36) is arranged between one end of the screw rod (30) located inside the piston rod (21) and the piston rod (21).

8. The compact actuating device according to claim 7, characterized in that The screw rod (30) is sleeved with a second retaining ring (33), and the second retaining ring (33) is used to limit the movement of the support ring bearing (36) along the axial direction of the screw rod (30).

9. The compact actuation device according to claim 1, characterized in that: A connecting assembly is provided between the cylinder body (1) and the driving mechanism (4), the connecting assembly comprising a connecting front flange (7) and a connecting rear flange (8), the connecting rear flange (8) being rigidly connected to the driving mechanism (4), the connecting front flange (7) being rigidly connected to the cylinder body (1), and the connecting front flange (7) being threadedly connected to the connecting rear flange (8).

10. The compact actuating device according to claim 9, characterized in that The front connection flange (7) and the rear connection flange (8) are integrally formed.

11. The compact actuation device according to claim 1, characterized in that A bearing seat (5) and a bearing cover (6) are arranged on the inner side of the end of the cylinder body (1); the bearing seat (5) and the bearing cover (6) are embedded in the inner wall of the cylinder body (1); the bearing seat (5) is arranged close to the driving mechanism (4); the screw rod (30) passes through the bearing seat (5) and the bearing cover (6) and is rotatably connected to the bearing seat (5) via a bearing.

12. The compact actuating device according to claim 11, characterized in that The end of the screw rod (30) is transmission-connected to the driving mechanism (4) via a coupling (9), and the coupling (9) presses the bearing cover (6) and the bearing tightly into the cylinder body (1).

13. The compact actuation device according to claim 1, characterized in that The end of the cylinder body (1) away from the driving mechanism (4) is connected to a front end cover (10), and the piston rod (21) can pass through the front end cover (10) and extend out of the cylinder body (1). The front end cover (10) is provided with an inner hole for the piston rod (21) to pass through, and a hole groove is formed on the side wall of the inner hole, and the hole groove is used to install the shaft sleeve (11) and the dust ring (12).

14. The compact actuating device according to claim 13, characterized in that A sealing ring (13) is sleeved on the front end cover (10), and the front end cover (10) is clamped and limited in position in the cylinder body (1) by a first retaining ring (14).

15. The compact actuation device according to claim 1, characterized in that The piston (20) is connected to a sensing element, and an induction switch is arranged on the inner wall of the cylinder body (1), and the induction switch cooperates with the sensor induction.

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