Magnetic suspension type linear actuating device

Abstract

The utility model discloses a magnetic suspension type linear actuating device which comprises a cylinder body, one end of the cylinder body is provided with a guide sleeve, and the inner wall of the guide sleeve is provided with a plurality of groups of magnetic induction coils; the magnetic conduction piston rod penetrates through the guide sleeve; the sensor is mounted on the guide sleeve and is used for detecting the radial position of the magnetic conductive piston rod; the controller is installed on the outer wall of the cylinder body, and the sensor and the magnetic induction coil are both connected with the controller. Through structural improvement, the piston rod is suspended in the center of the cylinder body by utilizing a magnetic suspension technology, so that on one hand, the friction force generated between the piston rod and the sealing ring is greatly reduced, and on the other hand, the problem of eccentric wear of the sealing ring is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of linear actuating devices, in particular to a magnetic suspension type linear actuating device. Background Art

[0002] A linear actuator is a device that realizes linear motion, such as a telescopic cylinder, an electric cylinder, etc. During the use of a linear actuator, due to the influence of its own weight or external force, the piston rod will inevitably be affected by the friction between its own gravity and the seal during the extension and retraction process. This friction will be magnified several times under certain conditions (especially when the cylinder is running at a low speed), resulting in "creeping" and "shaking". "Creeping" refers to the phenomenon of intermittent flow interruption due to the instability of the flow flowing into or out of the actuator (hydraulic cylinder, hydraulic motor) in the hydraulic system, resulting in the alternating sliding and stopping of the movement of the actuator. "Shaking" refers to the phenomenon that the radial position of the piston rod changes. Both phenomena will affect the operation of the linear actuator. In addition, due to the gravity of the piston rod itself, the seal will also cause eccentric wear and other phenomena, reducing the service life of the seal. Utility Model Content

[0003] In order to solve the problems existing in the prior art, the utility model provides a magnetic suspension type linear actuating device, which uses magnetic suspension technology to suspend the piston rod in the center of the cylinder body. On the one hand, it greatly reduces the friction generated between the piston rod and the sealing ring, and on the other hand, it improves the problem of eccentric wear of the sealing ring.

[0004] The technical solution adopted by the utility model to solve its technical problems is: a magnetic suspension type linear actuating device, comprising: a cylinder body, a guide sleeve is installed at one end of the cylinder body, and a plurality of groups of magnetic induction coils are arranged on the inner wall of the guide sleeve; a magnetic piston rod, the magnetic piston rod passes through the guide sleeve; a sensor, the sensor is installed on the guide sleeve and is used to detect the radial position of the magnetic piston rod; a controller, the controller is installed on the outer wall of the cylinder body, and the sensor and the magnetic induction coil are both connected to the controller.

[0005] Furthermore, the guide sleeve includes: a body and a mounting portion, the body and the mounting portion are integrally formed, and the multiple groups of magnetic induction coils are arranged on the inner wall of the mounting portion.

[0006] Furthermore, the sensor passes through the mounting portion along the radial direction of the guide sleeve.

[0007] Furthermore, each group of the magnetic induction coils includes a positive winding and a negative winding, and the sensor is arranged between the positive winding and the negative winding.

[0008] Furthermore, the guide sleeve is made of stainless steel.

[0009] Furthermore, a sealing assembly is installed on the inner wall of the body.

[0010] Furthermore, the number of the magnetic induction coils is four groups, and the four groups of magnetic induction coils are evenly distributed along the circumference of the inner wall of the mounting portion.

[0011] Furthermore, the sealing assembly includes: a first sealing ring, a second sealing ring and a third sealing ring which are arranged in sequence from right to left.

[0012] Furthermore, a groove for wiring is provided on the outer wall of the mounting portion.

[0013] Furthermore, the main body is located inside the cylinder body, and the mounting portion is located outside the cylinder body.

[0014] The beneficial effects of the utility model are:

[0015] By improving the structure of the guide sleeve, a magnetic induction coil is arranged on the inner wall of the guide sleeve, and the piston rod is made of magnetic conductive material. After the magnetic conductive piston rod passes through the guide sleeve, it cooperates with the magnetic induction coil. Under the action of the magnetic field, the magnetic conductive piston rod can be suspended in the center of the cylinder body. On the one hand, it can reduce the friction between the deadweight of the piston rod and the sealing ring, and reduce the "creeping" and "shaking" phenomenon of the linear actuator. On the other hand, it can also improve the problem of eccentric wear of the sealing ring. The gap between the magnetic conductive piston rod and the sensor can be detected by the sensor. If the gap on one side of the magnetic conductive piston rod becomes larger or smaller, the sensor feedbacks the signal to the controller. The controller changes the magnetic force of the magnetic induction coil on the corresponding side by adjusting the current signal, so that the magnetic conductive piston rod remains in the center of the cylinder body. In addition, the magnetic induction coil of the utility model is integrated on the guide sleeve, which improves the versatility and can be adapted to different linear actuators. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0017] Figure 1 It is a cross-sectional view of the linear actuating device of the utility model.

[0018] Figure 2 It is a structural schematic diagram of the guide sleeve of the utility model.

[0019] Figure 3 It is a structural schematic diagram of the magnetic induction coil and sensor of the utility model.

[0020] In the figure: 1. cylinder body; 2. guide sleeve; 3. magnetic piston rod; 4. piston; 5. sensor; 6. controller; 21. magnetic induction coil; 22. body; 23. mounting portion; 231. groove; 7. sealing assembly; 71. first sealing ring; 72. second sealing ring; 73. third sealing ring; 101. first oil port; 102. second oil port. DETAILED DESCRIPTION

[0021] 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.

[0022] 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.

[0023] 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.

[0024] like Figures 1 to 3 As shown, the magnetic suspension linear actuator of the utility model includes: a cylinder body 1, a guide sleeve 2, a magnetic piston rod 3, a sensor 5 and a controller 6. The guide sleeve 2 is installed at one end of the cylinder body 1. A plurality of groups of magnetic induction coils 21 are provided on the inner wall of the guide sleeve 2. The magnetic piston rod 3 passes through the guide sleeve 2. The sensor 5 is installed on the guide sleeve 2 for detecting the radial position of the magnetic piston rod 3. The controller 6 is installed on the outer wall of the cylinder body 1. The sensor 5 and the magnetic induction coil 21 are both connected to the controller 6.

[0025] The utility model improves the structure of the guide sleeve 2, sets a magnetic induction coil 21 on the inner wall of the guide sleeve 2, and the piston rod adopts a magnetic conductive material. After the magnetic conductive piston rod 3 passes through the guide sleeve 2, it cooperates with the magnetic induction coil 21. Under the action of the magnetic field, the magnetic conductive piston rod 3 can be suspended in the center position of the cylinder body 1. On the one hand, it can reduce the friction between the dead weight of the piston rod and the sealing ring, reduce the "creeping" and "shaking" phenomenon of the linear actuator, and on the other hand, it can also improve the problem of eccentric wear of the sealing ring. The size of the gap between the magnetic conductive piston rod 3 and the sensor 5 can be detected by the sensor 5. If the gap on one side of the magnetic conductive piston rod 3 becomes larger or smaller, the sensor 5 feeds back a signal to the controller 6. The controller 6 changes the magnetic force of the magnetic induction coil 21 on the corresponding side by adjusting the current signal, so that the magnetic conductive piston rod 3 remains in the center position of the cylinder body 1 (the axis of the piston rod coincides with the axis of the cylinder body 1).

[0026] In addition, the magnetic induction coil 21 of the utility model is integrated on the guide sleeve 2, which improves the versatility and can be adapted to different linear actuators. Magnetic suspension can be achieved by replacing the original guide sleeve 2 with the guide sleeve 2 of the utility model and then changing the material of the piston rod.

[0027] The linear actuator may be, for example, a telescopic cylinder, an electric cylinder, etc.

[0028] For example, the guide sleeve 2 includes: a body 22 and a mounting portion 23, the body 22 and the mounting portion 23 are integrally formed, and a plurality of groups of magnetic induction coils 21 are arranged on the inner wall of the mounting portion 23. The sensor 5 penetrates the mounting portion 23 along the radial direction of the guide sleeve 2. The difference between the guide sleeve 2 of the utility model and the conventional guide sleeve 2 is that the mounting portion 23 is added, and the mounting portion 23 occupies about 1 / 4 of the overall length of the guide sleeve 2. The change to the original structure is not large, which is conducive to saving the cost of transformation. Each group of magnetic induction coils 21 includes a positive winding and a negative winding, and the sensor 5 is arranged between the positive winding and the negative winding. In other words, the number of sensors 5 matches the number of magnetic induction coils 21. For example, the sensor 5 and the magnetic induction coil 21 are connected to the controller 6 through a connecting line, and a groove 231 for routing is provided on the outer wall of the mounting portion 23. That is, after the connection line passes through the mounting portion 23, it can be wound in the groove 231 and then connected to the controller 6. In this way, on the one hand, the connection line can be protected and the stability of signal transmission can be improved; on the other hand, it is conducive to improving the overall neatness and aesthetics of the linear actuator. For example, the body 22 is located inside the cylinder body 1, and the mounting portion 23 is located outside the cylinder body 1. The groove 231 is located outside the cylinder body 1, which is convenient for wiring.

[0029] For example, the guide sleeve 2 is made of stainless steel, which can improve the rigidity of the guide sleeve 2, thereby facilitating the improvement of the position stability of the magnetic induction coil 21. For example, the number of magnetic induction coils 21 is four, and the four groups of magnetic induction coils 21 are evenly distributed along the inner wall of the mounting portion 23. The number of sensors 5 is also four. For example, the four groups of magnetic induction coils 21 are respectively located at the upper, lower, left, and right positions of the magnetic piston rod 3. Of course, in other embodiments, the number of magnetic induction coils 21 can be changed.

[0030] For example, a sealing assembly 7 is installed on the inner wall of the body 22. The sealing assembly 7 includes: a first sealing ring 71, a second sealing ring 72 and a third sealing ring 73 arranged from right to left. The sealing assembly 7 can prevent the hydraulic oil inside the cylinder body 1 from leaking out, and can also prevent external dust from entering the cylinder body 1.

[0031] When the linear actuator is an oil cylinder, a piston 4 is provided at the end of the magnetic piston rod 3, and the piston 4 is located inside the cylinder body 1. The piston 4 divides the inside of the cylinder body 1 into a rod chamber and a rodless chamber. The cylinder body 1 is also provided with a first oil port 101 and a second oil port 102. The first oil port 101 is connected to the rod chamber, and the second oil port 102 is connected to the rodless chamber. The linear motion of the magnetic piston rod 3 is achieved by the pressure of the hydraulic oil.

[0032] When the linear actuator is an electric cylinder, a screw module is provided inside the cylinder body 1, the magnetic piston rod 3 is connected to the screw module, the screw module is driven by a right motor, and the screw module can drive the magnetic piston rod 3 to perform linear motion.

[0033] The working principle of this utility model:

[0034] The sensor 5 detects the size of the gap between itself and the magnetic piston rod 3 and provides real-time feedback to the controller 6. When the size of the gap on one side changes, it indicates that the position of the magnetic piston rod 3 has shifted. At this time, the controller 6 adjusts the current of the magnetic induction coil 21 on that side to change the magnetic force, so that the position of the magnetic piston rod 3 returns to the center of the cylinder 1.

[0035] In summary, the magnetic suspension type linear actuator of the utility model utilizes magnetic suspension technology to keep the magnetic piston rod 3 at the center of the cylinder body 1. On the one hand, it can reduce the friction between the piston rod and the seal due to its own weight, reduce friction loss, and improve transmission efficiency; on the other hand, it can also improve the problem of eccentric wear of the seal and increase the service life of the seal. In addition, the utility model has a simple structure, is easy to modify, and has strong versatility.

[0036] 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 magnetically suspended linear actuator, characterized in that: include: A cylinder body (1), wherein a guide sleeve (2) is installed at one end of the cylinder body (1), and a plurality of groups of magnetic induction coils (21) are arranged on the inner wall of the guide sleeve (2); A magnetic piston rod (3), wherein the magnetic piston rod (3) passes through the guide sleeve (2); A sensor (5), the sensor (5) being mounted on the guide sleeve (2) and being used for detecting the radial position of the magnetically conductive piston rod (3); A controller (6) is installed on the outer wall of the cylinder body (1), and the sensor (5) and the magnetic induction coil (21) are both connected to the controller (6).

2. The magnetic suspension linear actuator according to claim 1, characterized in that: The guide sleeve (2) comprises: a body (22) and a mounting portion (23); the body (22) and the mounting portion (23) are integrally formed; and the plurality of groups of magnetic induction coils (21) are arranged on the inner wall of the mounting portion (23).

3. The magnetic suspension linear actuator according to claim 2, characterized in that: The sensor (5) passes through the mounting portion (23) along the radial direction of the guide sleeve (2).

4. The magnetic suspension linear actuator according to claim 1, characterized in that: Each group of the magnetic induction coils (21) comprises a positive winding and a negative winding, and the sensor (5) is arranged between the positive winding and the negative winding.

5. The magnetic suspension linear actuator according to claim 1, characterized in that: The guide sleeve (2) is made of stainless steel.

6. The magnetic suspension linear actuator according to claim 2, characterized in that: A sealing assembly (7) is installed on the inner wall of the body (22).

7. The magnetic suspension linear actuator according to claim 2, characterized in that: The number of the magnetic induction coils (21) is four groups, and the four groups of magnetic induction coils (21) are evenly distributed along the circumference of the inner wall of the mounting portion (23).

8. The magnetic suspension linear actuator according to claim 6, characterized in that: The sealing assembly (7) comprises: a first sealing ring (71), a second sealing ring (72) and a third sealing ring (73) which are arranged in sequence from right to left.

9. The magnetic suspension linear actuator according to claim 2, characterized in that: A groove (231) for wiring is provided on the outer wall of the mounting portion (23).

10. The magnetic suspension linear actuator according to claim 2, characterized in that: The main body (22) is located inside the cylinder body (1), and the mounting portion (23) is located outside the cylinder body (1).

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