Linear synchronous motor

Abstract

The present invention discloses a linear synchronous motor, comprising: a driving device, comprising a stator and a rotor, wherein the rotor is rotatably arranged inside the stator about its own axis, and one end of the rotor is rotatably connected to the stator via a spherical surface, and the center of the spherical surface is located on the axis of the rotor; a sleeve, wherein the sleeve is mounted outside the stator; a rotating shaft, wherein one end of the rotating shaft is connected to the rotor, the rotating shaft is coaxially arranged with the rotor, and the rotor can drive the rotating shaft to rotate in the sleeve; and a driven member, wherein one of the sleeve and the rotating shaft is threadedly connected to the driven member, and the other is slidably connected to the driven member, so that the rotating shaft can drive the driven member to move along the axial direction of the rotating shaft. The connection between the rotor and the rotating shaft can remain stable during operation, thereby improving transmission efficiency, reducing noise, and extending service life.

Description

Technical Field

[0001] The present invention relates to the field of motors, and in particular to a linear synchronous motor. Background Art

[0002] A linear synchronous motor converts electrical energy into mechanical energy. It uses an energized coil to generate a rotating magnetic field, which acts on the rotor to create a magneto-electric torque. The rotor then drives an external shaft, which in turn drives a driven member in linear motion. This shaft then transmits the rotational power, converting it into linear motion.

[0003] In order to ensure that the rotors in most linear synchronous motors on the market can rotate stably in the stator, the inner side of the rotor is positioned on a connecting shaft protruding from the stator, and the other side of the rotor needs to be connected to the rotating shaft, and the rotating shaft also needs to be connected to the driven member. During the high-speed rotation of the rotating shaft, its own axis needs to always remain collinear with the axis of the rotor. However, since the rotating shaft and the rotor are not an integrally formed structure, there may be a certain error after assembly between them, resulting in the axis of the rotating shaft and the rotor being non-collinear, thereby causing the connection between the rotor and the rotating shaft to be unstable during rotation, causing noise inside the linear synchronous motor, seriously reducing the transmission efficiency, and shortening the service life of the linear synchronous motor. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a linear synchronous motor that can stabilize the connection between the rotor and the rotating shaft during operation, improve transmission efficiency, reduce noise, and extend service life.

[0005] According to the first aspect of the present invention, the linear synchronous motor includes: a driving device, the driving device includes a stator and a rotor, the rotor is rotatably arranged inside the stator around its own axis, and one end of the rotor is rotatably connected to the stator through a spherical surface, and the center of the sphere is located on the axis of the rotor; a sleeve, the sleeve is installed on the outside of the stator; a rotating shaft, one end of the rotating shaft is connected to the rotor, the rotating shaft and the rotor are coaxially arranged, and the rotor can drive the rotating shaft to rotate in the sleeve; a driven member, one of the sleeve and the rotating shaft is threadedly connected to the driven member, and the other is slidably connected to the driven member, so that the rotating shaft can drive the driven member to move along the axial direction of the rotating shaft.

[0006] The linear synchronous motor according to the embodiment of the present invention has at least the following beneficial effects:

[0007] By designing the contact between the rotor and the stator as a spherical contact structure, and the rotor is connected to one end of the rotating shaft, and the other end of the rotating shaft is connected to the driven member, when the axis of the rotating shaft and the axis of the rotor are not in a collinear state, the rotor can slide along the spherical surface in contact with the stator, so that the axis of the rotor is kept as collinear as possible with the axis of the rotating shaft, thereby making the connection between the rotor and the rotating shaft more stable during operation, improving transmission efficiency, reducing noise, and extending service life.

[0008] According to some embodiments of the present invention, a ball is provided between the rotor and the stator, the center of the ball is located in the axial direction of the rotor, and both the rotor and the stator are in contact with the spherical surface of the ball.

[0009] According to some embodiments of the present invention, the follower includes a push rod and a threaded retaining ring, the push rod is slidably disposed in a sleeve, the threaded retaining ring is located at one end of the push rod close to the driving device, the threaded retaining ring is threadedly connected to the rotating shaft and can be slidably engaged in the sleeve, and the rotating shaft can cooperate with the sleeve to drive the threaded retaining ring to slide along the axial direction of the rotating shaft, so as to drive the push rod to slide in the sleeve close to or away from the driving device.

[0010] According to some embodiments of the present invention, a sliding protrusion is provided on the outer side surface of the threaded retaining ring, and a sliding groove is provided on the inner side surface of the sleeve, and the sliding protrusion can be slidably engaged in the sliding groove.

[0011] According to some embodiments of the present invention, a bearing is provided on the rotating shaft, and a limiting groove is provided on the side of the sleeve close to the driving device. The bearing is located in the limiting groove, and the bearing is used to assist the relative rotation between the rotating shaft and the sleeve.

[0012] According to some embodiments of the present invention, a limiting plate is further sleeved on the rotating shaft, and the limiting plate is located on a side of the bearing close to the driving device.

[0013] According to some embodiments of the present invention, a mounting groove is concavely provided in the rotor, and a plug-in end is provided at one end of the rotating shaft close to the stator, and the plug-in end is engaged in the mounting groove.

[0014] According to some embodiments of the present invention, a card slot is concavely provided on the inner wall surface of the installation slot, and a card block is convexly provided on the plug-in end, and the card block is engaged in the card slot.

[0015] According to some embodiments of the present invention, an elastic body is provided in the mounting groove, and the elastic body is arranged between the rotating shaft and the rotor and is located in the axial direction of the rotating shaft.

[0016] According to some embodiments of the present invention, a positioning portion is convexly provided on a side of the sleeve close to the stator, and a positioning groove is concavely provided on a side of the stator close to the sleeve, and the positioning portion is engaged in the positioning groove.

[0017] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0019] Figure 1 is a three-dimensional schematic diagram of a linear synchronous motor according to an embodiment of the present invention;

[0020] Figure 2 for Figure 1 Exploded view of the sleeve, shaft and follower shown in FIG;

[0021] Figure 3 for Figure 1 An exploded view of the linear synchronous motor shown in FIG;

[0022] Figure 4 for Figure 1 The rotor and the exploded view of the rotor are shown in FIG;

[0023] Figure 5 for Figure 1 A cross-sectional view of a spring structure used in a linear synchronous motor shown in FIG;

[0024] Figure 6 for Figure 1 A cross-sectional view of a pad structure used in a linear synchronous motor is shown in FIG.

[0025] Reference numerals:

[0026] 100 driving device, 110 stator, 111 positioning groove, 120 rotor, 121 mounting groove, 122 slot, 123 elastic body, 130 ball bearing,

[0027] 200 sleeve, 210 slide, 220 limit groove, 230 positioning part,

[0028] 300 shaft, 310 bearing, 320 limit piece, 330 plug end, 331 block,

[0029] 400 follower, 410 ejector rod, 420 threaded retaining ring, 421 sliding protrusion. DETAILED DESCRIPTION

[0030] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0031] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0032] In the description of the present invention, "several" means more than one, "plurality" means more than two, "greater than," "less than," and "exceed" are understood to exclude the number itself, while "above," "below," and "within" are understood to include the number itself. The use of "first" and "second" in the description is solely for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, implicitly specifying the number of the indicated technical features, or implicitly specifying the order of the indicated technical features.

[0033] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0034] In the description of the present invention, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the exemplary expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0035] Reference below Figures 1 to 6 A linear synchronous motor according to an embodiment of the present invention is described.

[0036] like Figures 1 to 6 As shown, the linear synchronous motor according to an embodiment of the present invention includes: a driving device 100 , a sleeve 200 , a rotating shaft 300 and a driven member 400 .

[0037] The drive device 100 includes a stator 110 and a rotor 120. The rotor 120 is rotatably disposed within the stator 110 about its own axis, and one end of the rotor 120 is rotatably connected to the stator 110 via a spherical surface, with the center of the sphere located on the axis of the rotor 120. A sleeve 200 is mounted on the outside of the stator 110. One end of a rotating shaft 300 is connected to the rotor 120. The rotating shaft 300 and the rotor 120 are coaxially disposed, and the rotor 120 can drive the rotating shaft 300 to rotate within the sleeve 200. One of the sleeve 200 and the rotating shaft 300 is threadedly connected to the driven member 400, and the other is slidably connected to the driven member 400, so that the rotating shaft 300 can drive the driven member 400 to move axially along the rotating shaft 300.

[0038] For example, Figures 1 to 6 As shown, the driving device 100 may include a stator 110 and a rotor 120. The rotor 120 is rotatably arranged inside the stator 110 around its own axis. When the driving device 100 is energized, the stator 110 can drive the rotor 120 to rotate inside the stator 110, and one end of the rotor 120 is rotatably connected to the stator 110 through a spherical surface, and the center of the spherical surface is located on the axis of the rotor 120. The sleeve 200 can be installed on the driving device 100, and one end of the rotating shaft 300 is connected to the rotor 120. The axis of the rotating shaft 300 and the axis of the rotor 120 are collinear with each other. The rotor 120 can drive the rotating shaft 300 to rotate in the sleeve 200. The circumferential surface of the driven member 400 is connected to the sleeve 200, and one end of the driven member 400 is connected to the rotating shaft 300. The rotating shaft 300 can cooperate with the sleeve 200 to drive the driven member 400 to move away from or approach the driving device 100 along the axis of the rotating shaft 300.

[0039] Among them, the stator 110 is the fixed part of the motor. The stator 110 consists of three parts: the stator core, the stator winding and the motor housing. The main function of the stator 110 is to generate a rotating magnetic field, while the main function of the rotor 120 is to be cut by the magnetic lines of force in the rotating magnetic field and then generate (output) current. The sleeve 200 is mounted on the stator 110 by fasteners and is sleeved on the outer peripheral side of the rotating shaft 300 and the driven member 400. The driven member 400 is moved away from or close to the driving device 100 along the axial direction of the rotating shaft 300 in the sleeve 200 to provide a linear driving force.

[0040] Specifically, by designing the contact between the rotor 120 and the stator 110 to be in a spherical contact form, and the rotor 120 is connected to one end of the rotating shaft 300, and the other end of the rotating shaft 300 is connected to the driven member 400, when the axis of the rotating shaft 300 and the axis of the rotor 120 are not in a collinear state, the rotor 120 can rotate along the spherical surface in contact with the stator 110, so that the axis of the rotor 120 is kept as collinear as possible with the axis of the rotating shaft 300, thereby making the connection between the rotor 120 and the rotating shaft 300 more stable during operation, improving transmission efficiency, reducing noise, and extending service life.

[0041] In a further embodiment of the present invention, a ball 130 is provided between the rotor 120 and the stator 110, the center of the ball 130 is located in the axial direction of the rotor 120, and both the rotor 120 and the stator 110 are in spherical contact with the ball 130. Figure 2 、 Figure 5 and Figure 6 As shown, in this embodiment, a first groove is provided on the stator 110, and a second groove is provided on the side of the rotor 120 away from the rotating shaft 300. The ball 130 is arranged between the first groove and the second groove, and a gap is provided between the bottom surface of the rotor 120 and the stator 110. Therefore, the rotor 120 can rotate in the stator 110, and the rotor 120 can slide along the outer surface of the ball 130 to adjust its own axis to remain collinear with the axis of the rotating shaft 300 as much as possible. Therefore, during operation, the connection between the rotor 120 and the rotating shaft 300 is more stable, the transmission efficiency is improved, the noise is reduced, and the service life is extended.

[0042] In a further embodiment of the present invention, the driven member 400 includes a push rod 410 and a threaded snap ring 420. The push rod 410 is slidably disposed in the sleeve 200. The threaded snap ring 420 is located at one end of the push rod 410 close to the driving device 100. The threaded snap ring 420 is threadedly connected to the rotating shaft 300 and is slidably engaged in the sleeve 200. The rotating shaft 300 can cooperate with the sleeve 200 to drive the threaded snap ring 420 to slide along the axis of the rotating shaft 300, thereby driving the push rod 410 to slide in the sleeve 200 toward or away from the driving device 100. For example, Figure 3 、 Figure 5 and Figure 6 As shown, the follower 400 is designed to be composed of two parts, a push rod 410 and a threaded retaining ring 420. When one of the push rod 410 or the threaded retaining ring 420 is damaged, it can be replaced separately without replacing the entire follower 400, thereby saving material costs. The push rod 410 can also be adapted to be used on different threaded retaining rings 420, thereby improving the adaptability of the accessories.

[0043] Furthermore, a limiting protrusion is provided on one side of the threaded snap ring 420 close to the push rod 410. The interior of the push rod 410 is a hollow structure, and the inner side surface of the push rod 410 has no threaded structure. The limiting protrusion is engaged with the interior of the push rod 410 to keep the threaded snap ring 420 and the push rod 410 located in the extension direction of the rotating shaft 300; the outer side surface of the threaded snap ring 420 is slidably engaged with the inner side surface of the sleeve 200, so that the threaded snap ring 420 cannot rotate relative to the sleeve 200. At the same time, since the threaded snap ring 420 is threadedly connected to the rotating shaft 300, when the rotating shaft 300 rotates, the threaded snap ring 420 slides in the sleeve 200 along the extension direction of the rotating shaft 300 under the action of the threaded structure, and during the movement of the threaded snap ring 420, the push rod 410 can be driven to slide along the extension direction of the rotating shaft 300.

[0044] It can be understood that in some other embodiments, the rotating shaft 300 and the follower 400 are both arranged in the sleeve 200, the follower 400 is threadedly connected to the sleeve 200, the rotating shaft 300 and the follower 400 are slidably fitted together, and can drive the follower 400 to rotate in the sleeve 200. During the rotation of the follower 400 in the sleeve 200, under the action of the threaded structure, the follower 400 can approach or move away from the driving device 100 along the extension direction of the rotating shaft 300.

[0045] In a further embodiment of the present invention, a sliding protrusion 421 is provided on the outer side of the threaded retaining ring 420, and a sliding groove 210 is provided on the inner side of the sleeve 200, wherein the sliding protrusion 421 is slidably engaged in the sliding groove 210. Figure 3 、 Figure 5 and Figure 6 As shown, in this embodiment, four sliding protrusions 421 are provided on the threaded retaining ring 420, and the four sliding protrusions 421 are equidistantly distributed on the peripheral side of the threaded retaining ring 420. The four sliding protrusions 421 are in the form of long strips and are consistent with the sliding direction of the threaded retaining ring 420. The inner side surface of the sleeve 200 is also provided with four sliding grooves 210 adapted to the sliding protrusions 421. The four sliding grooves 210 do not extend to the outermost end away from the side of the driving device 100, mainly to prevent the threaded retaining ring 420 from disengaging from the rotating shaft 300 during relative movement, and to prevent the threaded retaining ring 420 from slipping out from the outermost end of the sleeve 200.

[0046] In a further embodiment of the present invention, a bearing 310 is sleeved on the rotating shaft 300, and a limiting groove 220 is provided on the side of the sleeve 200 close to the driving device 100. The bearing 310 is located in the limiting groove 220, and the bearing 310 is used to assist the relative rotation between the rotating shaft 300 and the sleeve 200. For example, Figure 5 and Figure 6As shown, the rotor 120 drives the rotating shaft 300 to rotate, and the rotating shaft 300 extends into the sleeve 200 through the limiting groove 220. The power output is achieved through the rotation of the rotating shaft 300. A bearing 310 is provided in the limiting groove 220, which can reduce the friction generated by the relative rotation between the rotating shaft 300 and the sleeve 200, so that the power output efficiency of the rotating shaft 300 is higher.

[0047] In a further embodiment of the present invention, a limiting plate 320 is further provided on the rotating shaft 300, and the limiting plate 320 is located on a side of the bearing 310 close to the driving device 100. For example, Figure 3 、 Figure 5 and Figure 6 As shown, in this embodiment, a concave annular groove is provided on the rotating shaft 300, and the limiting plate 320 is sleeved on the rotating shaft 300 and engaged in the annular groove. During assembly, the bearing 310 is sleeved on the rotating shaft 300 and rests against one end of the threaded structure to prevent the bearing 310 from sliding away from the driving device 100. Then the limiting plate 320 is engaged in the annular groove. The limiting plate 320 can prevent the bearing 310 from sliding toward the driving device 100, thereby limiting the bearing 310 on the rotating shaft 300, so that the rotating shaft 300 can be stably assisted to rotate in the sleeve 200.

[0048] In a further embodiment of the present invention, a mounting groove 121 is formed in the rotor 120, and a plug-in end 330 is formed at one end of the rotating shaft 300 close to the stator 110, and the plug-in end 330 is engaged in the mounting groove 121. Figure 2 、 Figures 4 to 6 As shown, by providing a mounting groove 121 on the rotor 120 and engaging the plug end 330 of the rotating shaft 300 in the mounting groove 121, when the stator 110 is energized to drive the rotor 120 to rotate, the rotor 120 can drive the rotating shaft 300 to rotate, thereby converting electrical energy into mechanical energy for power output. At the same time, if the rotating shaft 300 is designed as a long axis structure and is threadedly connected to the rotor 120, it is necessary to tap the threads on the rotating shaft 300, which increases the manufacturing cost and causes problems such as difficulty in controlling the overall concentricity of the motor, reduced motor efficiency, and shortened motor service life. By adopting a separate assembly structure for the rotor 120 and the rotating shaft 300, the length of the rotating shaft 300 can be greatly shortened, the manufacturing cost of the rotating shaft 300 can be reduced, and the transmission efficiency of the rotating shaft 300 can be effectively avoided from being reduced due to shaking of the driving device 100 during operation.

[0049] In a further embodiment of the present invention, a recessed slot 122 is provided on the inner wall of the mounting slot 121, and a block 331 is provided on the plug-in end 330, and the block 331 is engaged in the recessed slot 122. Figures 2 to 6As shown, in this embodiment, the number of the blocks 331 is three, and the three blocks 331 are evenly distributed on the peripheral side surface of the plug end 330. The number of the slots 122 is also three, and the three slots 122 are evenly distributed in the installation slot 121. When the blocks 331 are engaged in the slots 122, the rotating shaft 300 and the rotor 120 are limited, so that the rotor 120 can drive the rotating shaft 300 to rotate.

[0050] In a further embodiment of the present invention, an elastic body 123 is provided in the mounting groove 121. The elastic body 123 is provided between the rotating shaft 300 and the rotor 120 and is located in the axial direction of the rotating shaft 300. For example, Figure 2 and Figure 5 As shown, in this embodiment, the elastic body 123 is a spring. When the linear synchronous motor is assembled, the plug-in end 330 is inserted into the mounting groove 121, and the spring is in a compressed state, so that the spring has a reset reverse elastic force. At the same time, since the spring is located in the axial direction of the rotating shaft 300, the axes of the rotor 120 and the rotating shaft 300 are collinear with each other, so the spring gives the rotor 120 an elastic force along the axial direction of the rotor 120, so that the rotor 120 can maintain close contact with the ball 130, avoiding separation of the rotor 120 and the ball 130, thereby achieving more stable power transmission.

[0051] It is understandable that in some other instances, such as Figure 6 As shown, the elastomer 123 can also be an elastic gasket, wherein the elastic gasket has the same function as a spring, mainly providing an elastic force for the rotor 120 along the axis direction of the rotor 120, so that the rotor 120 can maintain close contact with the ball 130, avoiding the rotor 120 and the ball 130 from separating, thereby achieving more stable power transmission.

[0052] In a further embodiment of the present invention, a positioning portion 230 is convexly provided on a side of the sleeve 200 close to the stator 110, and a positioning groove 111 is concavely provided on a side of the stator 110 close to the sleeve 200, and the positioning portion 230 is engaged in the positioning groove 111. For example, Figure 2 、 Figure 3 、 Figure 5 and Figure 6 As shown, a positioning portion 230 is provided on the sleeve 200, and the positioning portion 230 is an annular structure. The installation groove 121 is also a circular groove. When installed, the positioning portion 230 can be engaged and positioned in the positioning groove 111, and then the sleeve 200 is installed on the stator 110 with fasteners.

[0053] While the embodiments of the present invention have been described in detail above with reference to the accompanying drawings, the present invention is not limited to the embodiments described above. Various modifications may be made within the scope of knowledge possessed by a person skilled in the art without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof may be combined with one another unless there is a conflict.

Claims

1. A linear synchronous motor, characterized in that: include: A drive device, the drive device comprising a stator and a rotor, the rotor being rotatably disposed within the stator about its own axis, one end of the rotor being rotatably connected to the stator via a spherical surface, the center of the spherical surface being located on the axis of the rotor, wherein a ball is disposed between the rotor and the stator, the center of the ball being located in the direction of the rotor axis, and both the rotor and the stator being in contact with the spherical surface of the ball; a sleeve, the sleeve being mounted on the outside of the stator; a rotating shaft, one end of which is connected to the rotor, the rotating shaft and the rotor being coaxially arranged, and the rotor being capable of driving the rotating shaft to rotate in the sleeve; A driven member, wherein one of the sleeve and the rotating shaft is threadedly connected to the driven member, and the other is slidably connected to the driven member, so that the rotating shaft can drive the driven member to move axially along the rotating shaft; the driven member includes a push rod and a threaded retaining ring, the push rod is slidably disposed in the sleeve, the threaded retaining ring is located at an end of the push rod close to the driving device, the threaded retaining ring is threadedly connected to the rotating shaft, and is slidably engaged in the sleeve; When the axis of the rotating shaft and the axis of the rotor are not in a collinear state, the rotor can slide along the outer surface of the ball so that the axis of the rotor and the axis of the rotating shaft remain collinear as much as possible.

2. The linear synchronous motor according to claim 1, characterized in that: The outer side surface of the threaded clamping ring is provided with a sliding protrusion, and the inner side surface of the sleeve is provided with a sliding groove, and the sliding protrusion can be slidably engaged in the sliding groove.

3. The linear synchronous motor according to claim 1, characterized in that: A bearing is sleeved on the rotating shaft, and a limiting groove is provided on a side of the sleeve close to the driving device, and the bearing is located in the limiting groove.

4. The linear synchronous motor according to claim 3, characterized in that: A limiting piece is also sleeved on the rotating shaft, and the limiting piece is located on a side of the bearing close to the driving device.

5. The linear synchronous motor according to claim 1, characterized in that: A mounting groove is concavely provided in the rotor, and a plug-in end is provided at one end of the rotating shaft close to the stator, and the plug-in end is engaged in the mounting groove.

6. The linear synchronous motor according to claim 5, characterized in that: A clamping groove is concavely provided on the inner wall surface of the installation groove, and a clamping block is convexly provided on the plug-in end, and the clamping block is clamped in the clamping groove.

7. The linear synchronous motor according to claim 5, characterized in that: An elastic body is provided in the installation groove. The elastic body is arranged between the rotating shaft and the rotor and is located in the axial direction of the rotating shaft.

8. The linear synchronous motor according to claim 1, characterized in that: A positioning portion is convexly provided on a side of the sleeve close to the stator, and a positioning groove is concavely provided on a side of the stator close to the sleeve, and the positioning portion is engaged in the positioning groove.

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