Servo

Abstract

This invention discloses a servo motor, comprising a housing assembly, a motor, a reduction mechanism, a transmission mechanism, a position sensor, and a locking mechanism. The motor is fixed within a first mounting cavity. The reduction mechanism is disposed within the housing assembly, and its input end is connected to the output shaft of the motor. The input end of the transmission mechanism is connected to the output end of the reduction mechanism, and its output end is adapted to connect to the input end of the driven object. The position sensor is mounted on the housing assembly and partially inserted into the transmission mechanism. The locking mechanism is sleeved on the output shaft of the motor to lock the output torque of the servo motor. At least one of the cables for the motor, position sensor, and locking mechanism passes through a through-hole. This invention improves the structure of the servo motor, achieving ultra-miniaturization, compact structure, and high transmission efficiency. The servo motor is self-locking upon power failure, can operate in low-temperature environments, solves the problem of servo motors failing to start due to frozen low-temperature lubricating grease, and improves the environmental adaptability of the servo motor.

Description

Technical Field

[0001] This invention relates to the field of servo motor technology, and more particularly to a linear output servo motor. Background Technology

[0002] Currently, linear servo motors are widely used in many fields. However, traditional servo motors are generally large in size and heavy in weight, and have low transmission efficiency. Especially when the servo motor output is high, it is often necessary to select a larger power motor and transmission structure, or to use a reduction mechanism to reduce the speed and increase the torque of the motor in order to achieve motor miniaturization. In order to achieve a high reduction ratio, new types of reducers such as harmonic reducers and RV reducers are often the first choice, but these types of reducers generally have low efficiency when the output is high. Summary of the Invention

[0003] The main objective of this invention is to provide a servo motor that reduces its size while ensuring high transmission efficiency.

[0004] To achieve the above objectives, the present invention proposes a servo motor, the servo motor comprising:

[0005] The housing assembly is provided with a first mounting cavity, a second mounting cavity, and a wire through hole;

[0006] The motor is fixed inside the first mounting cavity;

[0007] A speed reduction mechanism is disposed in the second mounting cavity, and the input end of the speed reduction mechanism is connected to the output shaft of the motor;

[0008] A transmission mechanism is disposed within the housing assembly. The input end of the transmission mechanism is connected to the output end of the reduction mechanism to convert rotational motion into linear motion. The output end of the transmission mechanism is adapted to be connected to the input end of the driven object.

[0009] A position sensor, mounted on the housing assembly and partially inserted into the transmission mechanism, is used to detect the displacement signal of the transmission mechanism; and

[0010] A locking mechanism is sleeved on the output shaft of the motor to lock the output torque of the servo motor;

[0011] In this configuration, at least one of the motor cable, the position sensor cable, and the locking mechanism cable passes through the cable hole.

[0012] Optionally, the locking mechanism includes a brake and a rotor hub, wherein the brake and the rotor hub are respectively coaxially arranged with the output shaft of the motor.

[0013] Optionally, the servo motor further includes a heating assembly disposed within the housing assembly and located on the transmission mechanism for heating the transmission mechanism.

[0014] Optionally, the heating assembly includes a heating sleeve and a heating wire. The heating sleeve is sleeved on the transmission mechanism and fixed to the housing assembly. The heating wire is disposed on the heating sleeve, and the heating sleeve has a wire hole for the cable of the heating wire to pass through.

[0015] Optionally, the heating sleeve is provided with an annular groove, the heating wire is placed in the annular groove, and the wire passage hole is opened on the groove wall of the annular groove.

[0016] Optionally, the heating sleeve has a first inner hole and a second inner hole communicating with the first inner hole. The first inner hole is for the transmission mechanism to be inserted. The inner wall of the housing assembly has a boss, which is engaged in the second inner hole to fix the heating sleeve to the housing assembly.

[0017] Optionally, the housing assembly is provided with an electrical communication interface, and the cables of the motor, the position sensor, and the locking mechanism are respectively connected to the electrical communication interface.

[0018] Optionally, the reduction mechanism is a reduction gear set, which includes a first gear, a second gear, a third gear, and a fourth gear. The shaft of the first gear is driven to be connected to the output shaft of the motor. The first gear meshes with the second gear, the third gear meshes with the fourth gear, and the second gear and the third gear are coaxially connected. The fourth gear is connected to the input end of the transmission mechanism.

[0019] Optionally, the lines connecting the center points of the axial end faces of the first gear, the second gear, the third gear, and the fourth gear form a triangle.

[0020] Optionally, the transmission mechanism is a ball screw or a planetary roller screw;

[0021] The ball screw is fixed to the housing assembly by a support bearing. The ball screw has a first step portion. The fourth gear is located on the first step portion. The fourth gear has a matching second step portion corresponding to the position of the first step portion. One side of the second step portion abuts against the support bearing, and the other side of the second step portion abuts against the nut.

[0022] In the technical solution of this invention, the servo motor includes a housing assembly, a motor, a reduction mechanism, a transmission mechanism, a position sensor, and a locking mechanism. The housing assembly has a first mounting cavity, a second mounting cavity, and a wiring hole. The motor is fixed in the first mounting cavity. The reduction mechanism is located inside the housing assembly, and its input end is connected to the output shaft of the motor. The transmission mechanism is located in the second mounting cavity, and its input end is connected to the output end of the reduction mechanism to convert rotational motion into linear motion. The output end of the transmission mechanism is adapted to connect to the input end of the driven object. The position sensor is mounted on the housing assembly and partially inserted into the transmission mechanism to detect the displacement signal of the transmission mechanism. The locking mechanism is sleeved on the output shaft of the motor to lock the output torque of the servo motor. At least one of the motor cable, the position sensor cable, and the locking mechanism cable passes through the wiring hole. Thus, through the above-mentioned optimized design, the internal space of the servo motor housing is utilized to the maximum extent. All electronic component wiring is located inside the housing, with no external exposure, reducing the overall size of the servo motor, resulting in a compact structure, reduced weight of the servo motor system, and high transmission efficiency. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the structure of an embodiment of the servo motor of the present invention;

[0025] Figure 2 This is a partial cross-sectional view of an embodiment of the servo motor of the present invention;

[0026] Figure 3 This is a schematic diagram of the housing assembly in one embodiment of the servo motor of the present invention;

[0027] Figure 4 This is a schematic diagram of the deceleration mechanism in one embodiment of the servo motor of the present invention;

[0028] Figure 5 This is a side view of the deceleration mechanism in one embodiment of the servo motor of the present invention;

[0029] Figure 6 This is a schematic diagram of the position sensor structure in one embodiment of the servo motor of the present invention;

[0030] Figure 7 This is a schematic diagram of the locking mechanism in one embodiment of the servo motor of the present invention;

[0031] Figure 8 This is a schematic diagram of the heating sleeve in one embodiment of the servo motor of the present invention;

[0032] Figure 9 This is a cross-sectional view of the heating sleeve in one embodiment of the servo motor of the present invention.

[0033] Explanation of icon numbers:

[0034] 10. Housing assembly; 20. Motor; 30. Reduction mechanism; 40. Transmission mechanism; 50. Position sensor; 60. Locking mechanism; 70. Heating assembly; 11. First housing; 12. Second housing; 10a. First mounting cavity; 10b. Second mounting cavity; 61. Brake; 62. Rotor hub; 71. Heating sleeve; 71a. First inner hole; 71b. Second inner hole; 71c. Annular groove; 31. First gear; 32. Second gear; 33. Third gear; 34. Fourth gear.

[0035] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0036] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0037] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0038] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, if the word "and / or" appears throughout the text, it means including three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution that simultaneously satisfies A and B. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0039] This invention proposes a servo motor, especially a linear output servo motor, which can be applied to aircraft, robots, or ships, etc., and is not limited thereto.

[0040] Reference Figures 1 to 3 In one embodiment of the present invention, the servo motor includes a housing assembly 10, a motor 20, a reduction mechanism 30, a transmission mechanism 40, a position sensor 50, and a locking mechanism 60. The housing assembly 10 is provided with a first mounting cavity 10a, a second mounting cavity 10b, and a wiring hole, wherein the first mounting cavity 10a and the second mounting cavity 10b are communicatively connected. The motor 20 is fixed in the first mounting cavity 10a. The reduction mechanism 30 is disposed in the housing assembly 10, partly located in the first mounting cavity 10a and partly located in the second mounting cavity 10b, that is, the reduction mechanism 30 can be disposed in the first mounting cavity 10a and the second mounting cavity 10b. At the connection point of the mounting cavity 10b, the input end of the reduction mechanism 30 is connected to the output shaft of the motor 20; the transmission mechanism 40 is disposed in the second mounting cavity 10b, and its input end is connected to the output end of the reduction mechanism 30 to convert rotary motion into linear motion. The output end of the transmission mechanism 40 is adapted to be connected to the input end of the driven object; the position sensor 50 is mounted on the housing assembly 10 and partially inserted into the transmission mechanism 40 to detect the displacement signal of the transmission mechanism 40; the locking mechanism 60 is sleeved on the output shaft of the motor 20 to lock the output torque of the servo motor. At least one of the cables of the motor 20, the position sensor 50, and the locking mechanism 60 passes through a through-hole.

[0041] It should be noted that the object driven by motor 20 can be the moving parts of aircraft, robots, or ships, etc., and there is no limitation here.

[0042] refer to Figure 2 and Figure 3In this embodiment, the housing assembly 10 can be an irregularly shaped structure, specifically including a first housing 11 and a second housing 12. The first housing 11 has a two-cavity structure, that is, a first mounting cavity 10a and a second mounting cavity 10b are disposed within the first housing 11. Internal wiring holes can be provided on the first housing 11 and / or the second housing 12 to facilitate the internal routing of cables for the motor 20, position sensor 50, locking mechanism 60, and the heating component 70 described below. All electronic component wiring is located within the housing assembly 10, with no external exposure, thus improving product reliability. Of course, in some other embodiments, the housing assembly 10 can also be a one-piece molded housing, or assembled from multiple housings; this is not limited here.

[0043] In this embodiment, the deceleration mechanism 30 may be a gear assembly or other deceleration device, which is not limited here.

[0044] In this embodiment, the transmission mechanism 40 can be a ball screw or a planetary roller screw, etc., and is not limited here.

[0045] refer to Figure 6 In this embodiment, the position sensor 50 can be an integrated small sliding position sensor, which includes a main body and a sliding part. The sensor body can be fixed to the first housing 11 with screws, and one end of the sliding part can be inserted into the mounting hole of the transmission mechanism 40. The linear motion part of the transmission mechanism 40 drives the linear sliding part of the sensor to slide linearly. In this way, the operational stability of the servo motor can be improved.

[0046] refer to Figure 7 In this embodiment, the locking mechanism 60 may include a brake 61 and a rotor hub 62, which are coaxially arranged with the output shaft of the motor 20. The locking mechanism 60 is relatively simple to install, requiring no clearance adjustment. Its function is to achieve torque locking of the servo motor output. It is connected to the locking shaft via the rotor hub 62 and has two locking methods: one is to directly lock the output shaft of the motor 20, and the other is to rationally position the reduction mechanism 30 through a parallel shaft reduction configuration. This invention achieves a locking function; through proper configuration, the servo motor can achieve the required locking torque, and even in abnormal locking conditions, the motor 20 can still output torque.

[0047] In the technical solution of this invention, the servo motor includes a housing assembly 10, a motor 20, a reduction mechanism 30, a transmission mechanism 40, a position sensor 50, and a locking mechanism 60. The housing assembly 10 has a first mounting cavity 10a, a second mounting cavity 10b, and a wiring hole. The motor 20 is fixed in the first mounting cavity 10a. The reduction mechanism 30 is disposed in the housing assembly 10, and its input end is connected to the output shaft of the motor 20. The transmission mechanism 40 is disposed in the second mounting cavity 10b, and its input end is connected to the output end of the reduction mechanism 30 to convert rotational motion into linear motion. The output end of the transmission mechanism 40 is adapted to connect to the input end of the driven object. The position sensor 50 is mounted on the housing assembly 10 and partially inserted into the transmission mechanism 40 to detect the displacement signal of the transmission mechanism 40. The locking mechanism 60 is sleeved on the output shaft of the motor 20 to lock the output torque of the servo motor. At least one of the cables of the motor 20, the position sensor 50, and the locking mechanism 60 passes through the wiring hole. Thus, through the above-mentioned reasonable optimization design, the internal space of the servo housing is utilized to the maximum extent. All electronic components are routed inside the housing, with no external exposed wiring. This reduces the overall size of the servo, resulting in a compact structure, reduced weight of the servo system, and higher transmission efficiency.

[0048] In some low-temperature environments, servo motors may experience starting difficulties due to frozen grease. To address this, the servo motor of the present invention may further include a heating component 70, which is disposed within the housing assembly 10 and located on the transmission mechanism 40. The heating component 70 is used to heat the transmission mechanism 40, enabling the servo motor to operate in low-temperature environments. This solves the problem of the servo motor failing to start due to frozen grease under low-temperature conditions and improves the environmental adaptability of the servo motor.

[0049] Further, refer to Figure 8 and Figure 9 In one embodiment, the heating assembly 70 may include a heating sleeve 71 and a heating wire. The heating sleeve 71 is sleeved on the transmission mechanism 40 and fixed on the housing assembly 10. The heating wire is disposed on the heating sleeve 71, and the heating sleeve 71 has a wire hole for the cable of the heating wire to pass through.

[0050] Heating sleeve 71 is heated by heating wire, and the heating sleeve 71 transfers heat to the first housing 11 and transmission mechanism 40, thereby heating the first housing 11 and transmission mechanism 40, avoiding the problem of difficult start-up of servo motor at low temperature, and improving the environmental adaptability range of servo motor.

[0051] Main reference Figure 9 In this embodiment, the heating sleeve 71 is provided with an annular groove 71c, the heating wire is placed in the annular groove 71c, and the wire hole is opened on the groove wall of the annular groove 71c. In this way, it is convenient to install the power cord of the heating wire, making the servo motor structure more compact.

[0052] Furthermore, refer to Figure 9 The heating sleeve 71 may be provided with a first inner hole 71a and a second inner hole 71b communicating with the first inner hole 71a. The first inner hole 71a is for the transmission mechanism 40 to be inserted. The inner wall of the housing assembly 10 is provided with a boss, which is inserted into the second inner hole 71b to fix the heating sleeve 71 on the housing assembly 10.

[0053] The heating sleeve 71 may have stepped structures on both sides of the annular groove 71c. These stepped structures can be connected to the first housing 11 and function as end cover baffles. Furthermore, the heating sleeve 71 can be made of beryllium bronze, a material known for its wear resistance and high thermal conductivity; this is not a limitation.

[0054] To further miniaturize the servo motor, in one embodiment, the housing assembly 10 may be provided with an electrical communication interface, through which the cables of the motor 20, the position sensor 50, and the locking mechanism 60 are respectively connected. This also facilitates connection to control devices or other devices.

[0055] Please refer to Figure 4 and Figure 5 In one embodiment, the reduction mechanism 30 is a reduction gear set, which may include a first gear 31, a second gear 32, a third gear 33 and a fourth gear 34. The shaft of the first gear 31 is driven to be connected to the output shaft of the motor 20. The first gear 31 meshes with the second gear 32, the third gear 33 meshes with the fourth gear 34, and the second gear 32 and the third gear 33 are coaxially connected. The fourth gear 34 is connected to the input end of the transmission mechanism 40 to further improve the transmission efficiency of the servo motor.

[0056] It should be noted that, in order to achieve better machinability, the second gear 32 and the third gear 33 can be interference-fitted, with two implementation methods: tooth interference or shaft interference. Specifically, one method is that the addendum circle of the third gear 33 is interference-fitted with the center hole of the second gear 32, and the other method is that a stepped shaft is provided on the third gear 33 and interference-fitted with the center hole of the second gear 32.

[0057] Furthermore, the center points of the axial end faces of the first gear 31, the second gear 32, the third gear 33 and the fourth gear 34 are connected to form a triangle, so as to make the internal structure of the servo motor more compact, further reduce the size of the servo motor, and also improve the transmission efficiency.

[0058] In this embodiment, the gear type can be selected according to the actual deceleration situation and space constraints. It can be a spur gear or a helical gear, with spur gears being preferred. By selecting a reasonable number of teeth, module, and displacement coefficient based on the actual reduction ratio, a large reduction ratio transmission design can be achieved. The reduction gear system realizes the reduction and torque increase of the motor 20 output. To further achieve miniaturization, the reduction gear layout can adopt a triangular layout design. The angle of the triangle can be reasonably allocated according to actual needs. By adjusting the angle of the triangle, the shape structure of the servo motor can be changed to minimize and make reasonable use of space.

[0059] In one embodiment, the transmission mechanism 40 adopts a ball screw, which is fixed to the housing assembly 10 by a support bearing. The ball screw is provided with a first step portion, and the fourth gear 34 is located on the first step portion. The fourth gear 34 is provided with a matching second step portion corresponding to the position of the first step portion, and one side of the second step portion abuts against the support bearing, and the other side of the second step portion abuts against the nut.

[0060] In this embodiment, the support bearing can be an angular contact support bearing, but it is not limited here.

[0061] The fourth gear 34 is fixed in the axial direction of the transmission mechanism 40 by setting a nut, and the angular contact support bearing on the transmission mechanism 40 is axially locked, which further improves the reliability of the servo motor.

[0062] The above description is merely an optional embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A steering gear, characterized in that The rudder comprises: a housing assembly provided with a first mounting cavity, a second mounting cavity and a wire hole; a motor fixed in the first mounting cavity; a speed reduction mechanism arranged in the housing assembly, an input end of the speed reduction mechanism being connected with an output shaft of the motor; a transmission mechanism arranged in the second mounting cavity, an input end of the transmission mechanism being connected with an output end of the speed reduction mechanism for converting rotary motion into linear motion, and an output end of the transmission mechanism being adapted to be connected with an input end of a driving object; a position sensor mounted on the housing assembly and partially arranged in the transmission mechanism for detecting displacement signals of the transmission mechanism; and a locking mechanism sleeved on the output shaft of the motor for locking an output torque of the rudder; at least one of a cable of the motor, a cable of the position sensor and a cable of the locking mechanism passes through the wire hole; a heating assembly arranged in the housing assembly and located on the transmission mechanism for heating the transmission mechanism; the heating assembly comprises a heating sleeve and a heating wire, the heating sleeve is sleeved on the transmission mechanism and fixed on the housing assembly, the heating wire is arranged on the heating sleeve, and a wire hole is formed in the heating sleeve for the cable of the heating wire to pass through; the heating sleeve is provided with a first inner hole and a second inner hole in communication with the first inner hole, the first inner hole is for the transmission mechanism to be inserted, and an inner wall of the housing assembly is provided with a boss, the boss is clamped into the second inner hole to fix the heating sleeve on the housing assembly.

2. The servo motor of claim 1, wherein, The locking mechanism comprises a brake and a rotor hub, and the brake and the rotor hub are coaxially arranged with the output shaft of the motor.

3. The servo motor of claim 1, wherein, The heating sleeve is provided with an annular groove, the heating wire is arranged in the annular groove, and the wire hole is formed in the groove wall of the annular groove.

4. The steering gear according to any one of claims 1 to 3, characterized in that An electrical communication interface is arranged on the housing assembly, and the cable of the motor, the cable of the position sensor and the cable of the locking mechanism are connected with the electrical communication interface respectively.

5. The actuator of claim 1, wherein, The speed reduction mechanism is a speed reduction gear set, the speed reduction gear set comprises a first gear, a second gear, a third gear and a fourth gear, a rotating shaft of the first gear is drivingly connected with the output shaft of the motor, the first gear is engaged with the second gear, the third gear is engaged with the fourth gear, the second gear is coaxially connected with the third gear, and the fourth gear is connected with the input end of the transmission mechanism.

6. The servo motor of claim 5 wherein, The first gear, the second gear, the third gear and the fourth gear are connected with the center points of the axial end faces to form a triangle.

7. The servo motor of claim 5 wherein, The transmission mechanism is a ball screw; The ball screw is fixed on the housing assembly through a support bearing, the ball screw is provided with a first stepped portion, the fourth gear is located on the first stepped portion, the fourth gear is provided with a second stepped portion corresponding to the position of the first stepped portion, one side of the second stepped portion abuts against the support bearing, and the other side of the second stepped portion abuts against through a nut.

Images