Motor with rear centrifugal brake, linear actuating device and lifting platform

Abstract

The utility model relates to the technical field of electric drive equipment, in particular to a motor of a rear centrifugal brake, a linear actuating device and a lifting platform, the motor of the rear centrifugal brake comprises a main machine shell and a speed limiting box shell, and the speed limiting box shell is arranged at the rear end of the main machine shell; the motor shaft is rotationally connected into the main machine shell, and the output end of the motor shaft penetrates through the main machine shell; the driving assembly is arranged in the main machine shell and used for driving the motor shaft to rotate; the centrifugal assembly is arranged in the speed limiting box shell; wherein the rear end of the motor shaft penetrates through the main machine shell and extends into the speed limiting box shell to be connected with the centrifugal assembly, and the centrifugal assembly brakes the motor shaft through friction between the centrifugal assembly and the inner side wall of the speed limiting box shell. The centrifugal assembly is arranged at the rear end of the motor and is convenient to disassemble, assemble, replace and maintain.

Description

Technical Field

[0001] The present application relates to the technical field of electric drive equipment, and in particular to a motor of a rear centrifugal brake, a linear actuator and a lifting platform. Background Art

[0002] The core components of the electric cylinder include a reducer, a motor, and a screw. Electric cylinders are used in some specific industries that often require higher safety performance, especially lifting platforms with manned functions.

[0003] When the motor in the electric cylinder is powered on and working normally, the electromagnetic brake in the motor is fully opened, and the reducer operates normally, so that the electric cylinder can operate normally. After power failure, the electromagnetic brake in the motor is fully closed, the reducer stops running, and the electric cylinder stops running, but the electromagnetic brake in the motor can be mechanically opened by pulling the external manual release. However, when the electromagnetic brake in the motor fails and cannot provide braking torque, or when the electromagnetic brake in the motor is manually released, the electric cylinder will rotate in the direction of the external torque under the condition of external torque. When the external torque is much greater than the friction torque of the electric cylinder itself, the electric cylinder will stall, causing the lifting platform in the lifting platform to stall and land, which is prone to dangerous situations.

[0004] In this case, a brake, such as a centrifugal brake, is usually added to the motor. When the motor shaft stalls, the centrifugal brake locks the motor shaft by friction with the external housing. Existing centrifugal brakes are usually arranged inside the motor. Since the centrifugal brake brakes by friction, the centrifugal brake is prone to wear. Therefore, the centrifugal brake needs to be replaced and maintained regularly to ensure its normal use. Adding a centrifugal brake to the motor requires major modification of the motor and change of the internal structure of the motor. When replacing and maintaining the centrifugal brake, the motor needs to be disassembled, which makes replacement and maintenance of the centrifugal brake more difficult. Utility Model Content

[0005] The technical problem to be solved by the utility model is that the existing motor with a centrifugal brake needs to be modified during installation, and the subsequent maintenance of the centrifugal brake is relatively difficult.

[0006] To this end, the utility model provides a motor with a rear centrifugal brake, a linear actuating device and a lifting platform.

[0007] The technical solution adopted by the utility model to solve its technical problems is:

[0008] A motor with a rear centrifugal brake, comprising:

[0009] The main chassis, and

[0010] A speed limiting case shell, which is arranged at the rear end of the main housing;

[0011] A motor shaft, the motor shaft is rotatably connected in the main housing, and an output end of the motor shaft passes through the main housing;

[0012] A driving assembly, which is disposed in the main housing and is used to drive the motor shaft to rotate;

[0013] A centrifugal assembly, wherein the centrifugal assembly is disposed in a speed limiting housing;

[0014] The rear end of the motor shaft penetrates the main housing and extends into the speed limiting case to be connected with the centrifugal assembly. The centrifugal assembly brakes the motor shaft through friction with the inner wall of the speed limiting case.

[0015] By adopting the above technical solution, the centrifugal assembly is separately arranged in the speed limiting case shell, the speed limiting case shell is arranged at the rear end of the main case, the driving assembly is arranged in the main case, and the centrifugal assembly and the speed limiting case shell form a modular unit. The present application directly adds the modular unit to the rear end of the existing motor, so that the changes to the existing motor can be minimized during the installation of the centrifugal assembly, and in the process of replacing and disassembling the centrifugal assembly, it is only necessary to remove the speed limiting case shell to achieve maintenance and replacement of the centrifugal assembly.

[0016] Furthermore, the centrifugal assembly includes a counterweight block, which is slidably connected to the motor shaft along the radial direction of the motor shaft. The side wall of the counterweight block away from the motor shaft has friction and is used to abut against the inner wall of the speed limit box shell. The counterweight block is provided with a spring.

[0017] By adopting the above technical solution, when the motor shaft stalls, the counterweight block is thrown out under the action of centrifugal force and brakes by friction with the inner wall of the speed limit box shell, thereby braking the motor shaft.

[0018] Furthermore, the centrifugal assembly also includes an inner sleeve, which is coaxially sleeved on the motor shaft, and the counterweight is slidably connected to the inner sleeve along the radial direction of the inner sleeve.

[0019] Furthermore, the shape of the side wall of the counterweight block that abuts against the inner side wall of the speed limit box shell is adapted to the inner side wall of the speed limit box shell.

[0020] Furthermore, a plurality of the counterweight blocks are provided, and the plurality of the counterweight blocks are circumferentially arranged on the outer side wall of the inner sleeve.

[0021] Furthermore, an arc-shaped limiting groove is arranged on the end face of each of the counterweight blocks, and the limiting grooves on the multiple counterweight blocks form a limiting ring groove. The spring is arranged as a closed ring, and the spring is embedded in the limiting ring groove.

[0022] Furthermore, the front end of the inner sleeve is sealed and connected to the main housing via an O-ring.

[0023] By adopting the above technical solution, the setting of the O-ring can prevent powder debris generated by the friction between the counterweight block and the inner wall of the speed limit box shell from entering the electromagnetic brake, thereby affecting the opening and closing functions of the electromagnetic brake, protecting the electromagnetic brake, reducing the possibility of electromagnetic brake failure, and increasing the service life of the electromagnetic brake.

[0024] Furthermore, a deep groove ball bearing is provided between the rear end of the centrifugal assembly and the speed limiting housing, and the deep groove ball bearing is used for press-fitting the centrifugal assembly.

[0025] Furthermore, a disc spring is installed between the deep groove ball bearing and the speed limiter housing.

[0026] Furthermore, a retaining spring is connected to the motor shaft, and the retaining spring is arranged at the front end of the centrifugal assembly and is used to position the centrifugal assembly.

[0027] Furthermore, an electromagnetic clutch is arranged in the main housing, and the electromagnetic clutch is used to brake the motor shaft.

[0028] Furthermore, a manual release is provided on the main housing, and the manual release is connected to the electromagnetic brake.

[0029] Furthermore, a detection meter is provided on the main housing, and the detection meter is used to detect the current of the driving component or the rotation speed of the motor shaft.

[0030] A linear actuator, comprising:

[0031] Drivers, and

[0032] A reducer connected to the driver;

[0033] The motor of the rear centrifugal brake as described above, wherein the motor of the rear centrifugal brake drives the driver through a speed reducer.

[0034] Furthermore, the centrifugal assembly is arranged on a side away from the reducer.

[0035] A lifting platform uses the above-mentioned linear actuator as a driving source.

[0036] The beneficial effect of the utility model is that the centrifugal assembly and the speed limiting case are arranged as a modular unit at the rear end of the motor main body, and the counterweight, spring, and inner sleeve are installed on the motor shaft as a whole. In this way, the workload is reduced when the user installs, because there is already a complete set of pre-assembled modular units, and there is no need to install the electric cylinder and brake separately. The modular unit is directly added to the rear end of the existing motor. In the process of replacing and disassembling the centrifugal assembly, the speed limiting case at the rear end of the main housing is directly disassembled to maintain and replace the centrifugal assembly. The two ends of the centrifugal assembly are limited by the retaining ring and the deep groove ball bearing, which improves the axial stability of the centrifugal assembly, can better control noise and vibration, and improve the comfort of operation.

[0037] Since the centrifugal assembly is manufactured as a whole, it can be directly added to the rear end of the motor body. Therefore, only the length of the motor shaft needs to be increased, and no other modifications are required to the motor body. The motor can still be tested for dynamic balancing. The motor with a rear centrifugal brake can improve the reliability of the system by reducing the connectors and transmission elements in the transmission chain, reducing the possibility of failure.

[0038] In addition, an O-ring is arranged at the connection between the centrifugal assembly and the main housing to prevent powder debris generated by the friction between the counterweight block and the inner wall of the speed limit box housing from entering the electromagnetic brake, thereby affecting the opening and closing function of the electromagnetic brake, protecting the electromagnetic brake, reducing the possibility of electromagnetic brake failure, and increasing the service life of the electromagnetic brake.

[0039] In addition, due to the integration of the system, maintenance points are easier to access, and component replacement and inspection are more convenient. Additional parts and fasteners are reduced, reducing overall assembly costs, saving material costs and labor costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0041] Figure 1 It is a structural schematic diagram of the motor of the rear centrifugal brake in the utility model.

[0042] Figure 2 It is a structural schematic diagram of the centrifugal assembly in the utility model.

[0043] Figure 3 It is a structural schematic diagram of the linear actuating device in the utility model.

[0044] In the figure: 1. Motor; 10. Main housing; 11. Speed ​​limit box housing; 12. Drive assembly; 13. Motor shaft; 14. Braking mechanism; 141. Electromagnetic brake; 142. Manual release; 15. O-ring; 16. Retaining spring; 17. Deep groove ball bearing; 18. Disc spring; 19. Centrifugal assembly; 191. Inner sleeve; 192. Counterweight; 193. Spring; 194. Limiting groove; 2. Reducer; 3. Driver. DETAILED DESCRIPTION

[0045] 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.

[0046] 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.

[0047] 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.

[0048] Example 1

[0049] Reference Figure 1 , 2 A motor 1 with a rear centrifugal brake includes a housing, a driving component 12, a motor shaft 13, a brake mechanism 14 and a centrifugal component 19. The housing includes a main housing 10 and a speed limiting case housing 11. The driving component 12 is connected to the main housing 10. The motor shaft 13 passes through the main housing 10. The driving component 12 is connected to the motor shaft 13 to drive the motor shaft 13 to rotate.

[0050] With the output end of the motor shaft 13 as the front end, the speed limiter housing 11 is fixedly connected to the rear end of the main housing 10 by screws. The brake mechanism 14 includes an electromagnetic brake 141 and a manual release 142. The electromagnetic brake 141 is connected inside the main housing 10 and arranged near the rear end. The manual release 142 is connected to the main housing 10. The electromagnetic brake 141 is used to brake the motor shaft 13, and the manual release 142 acts on the electromagnetic clutch.

[0051] The centrifugal assembly 19 is arranged in the speed limiting case 11. The rear end of the motor shaft 13 passes through the main case 10 and extends into the speed limiting case 11 to be connected to the centrifugal assembly 19. The centrifugal assembly 19 is used to brake the motor shaft 13. A retaining spring 16 is connected to the motor shaft 13. The retaining spring 16 is located at the front end of the centrifugal assembly 19. The retaining spring 16 is used to locate the axial installation position of the centrifugal assembly 19. A deep groove ball bearing 17 is connected to the rear end of the motor shaft 13. The deep groove ball bearing 17 presses the centrifugal assembly 19 onto the motor shaft 13. A disc spring 18 is installed between the deep groove ball bearing 17 and the speed limiting case 11.

[0052] The centrifugal assembly 19 includes an inner sleeve 191, a counterweight 192 and a spring 193. The inner sleeve 191 is coaxially sleeved on the motor shaft 13. The front end of the inner sleeve 191 extends into the main housing 10. The front end of the inner sleeve 191 is sealed and connected to the main housing 10 via an O-ring 15. A plurality of counterweights 192 are provided. The plurality of counterweights 192 are circumferentially arranged on the outer wall of the inner sleeve 191. The counterweights 192 are slidably connected to the inner sleeve 191 along the radial direction of the inner sleeve 191. The side wall of the counterweight 192 away from the inner sleeve 191 is a contact surface. The contact surface is frictional. The contact surface is used to abut against the inner wall of the speed limit case shell 11. The material of the speed limit case shell 11 is a hard metal with a certain roughness and friction resistance in the inner hole. The shape of the contact surface is adapted to the inner wall of the speed limit case shell 11. Each counterweight block 192 is provided with an arc-shaped limiting groove 194 on the front and rear end surfaces. The limiting grooves 194 on the multiple counterweight blocks 192 form an annular limiting ring groove. The spring 193 is configured as a closed ring and is embedded in the limiting ring groove.

[0053] When the motor 1 is powered on and working normally, the electromagnetic brake 141 is fully opened, the motor 1 operates normally, and the drive assembly 12 drives the motor shaft 13 to rotate. After power failure, the electromagnetic brake 141 is fully closed, and the motor shaft 13 stops running, but the electromagnetic brake 141 in the motor 1 can be mechanically opened by pulling the external manual release 142.

[0054] When the electromagnetic brake 141 in the main housing 10 fails and cannot provide braking torque, or when the electromagnetic brake 141 is manually released and the linear actuator is subjected to an external force, the linear actuator will tend to move in the direction of the external force. When the external force is much greater than the friction of the electric cylinder itself, the linear actuator will stall, which may lead to dangerous situations in some specific application scenarios. However, after the centrifugal brake is added, the higher the stall speed, the greater the centrifugal force generated by the stall. Once the centrifugal force of the stall exceeds the tension of the spring 193, the tensioned frictional counterweight 192 will be thrown out and rub against the inner wall of the speed limit box housing 11. At this time, most of the kinetic energy is converted into internal energy, resulting in a deceleration braking effect.

[0055] During the braking process of the centrifugal brake, the frictional counterweight 192 and the speed limit box will produce powder debris after friction braking. An O-ring 15 is installed at the connection between the inner sleeve 191 and the main housing 10 to prevent the generated powder debris from entering the electromagnetic brake 141, thereby affecting the opening and closing function of the electromagnetic brake 141.

[0056] Example 2

[0057] Reference Figure 1 , 3 A linear actuator device includes a driver 3, a reducer 2, and a motor 1 of the rear centrifugal brake as described in Example 1, wherein the motor 1 is rigidly connected to the reducer 2, and the motor 1 is connected to the driver 3 through the reducer 2. The driver 3 can be a linear actuator device such as an electric cylinder, and the driver 3 includes a rotating shaft, which is connected to the motor shaft 13.

[0058] Example 3

[0059] A lifting platform, which uses the linear actuator described in Example 3 as a driving source.

[0060] Lifting platforms include but are not limited to mast-type aerial work platforms, cranes, etc. Lifting platforms usually use linear actuators to drive corresponding load-bearing platforms.

[0061] When an emergency occurs on the lifting platform (such as a sudden power outage) and an emergency descent is required, a deceleration protection is required. At this time, the electromagnetic brake 141 closes and locks the motor shaft 13. At this time, the lifting platform is at a certain height and is dangerous. It is necessary to descend the platform as soon as possible. At this time, the manual release 142 can be pulled, and the electromagnetic brake 141 in the motor 1 is opened accordingly. Under the action of gravity acceleration, the electric cylinder begins to accelerate and retract, and the motor shaft 13 will rotate at a faster speed. When the centrifugal force caused by the speed exceeds the tension of the spring 193, the counterweight 192 is thrown out and rubs against the inner wall of the speed limit box. The kinetic energy loss is heat energy, and the motor slows down and falls.

[0062] Example 4

[0063] The difference from the first embodiment is that a detection meter is provided on the motor 1, and the detection meter may be a current detection meter or a rotation speed detection meter.

[0064] Since the centrifugal assembly 19 is braked by friction deceleration, it will inevitably be worn out and needs to be replaced from time to time. This wear can be monitored by the speed value of the motor 1.

[0065] In this embodiment, the detection meter is a speed detection meter. After the motor 1 with a centrifugal brake is installed on the electric cylinder, the rated load is applied for emergency fallback and the fallback speed is tested. After a period of use, the rated load is applied for emergency fallback again to compare the speeds. When the electric speed difference is large, a new centrifugal component 19 is replaced in time.

[0066] In summary, in this application, the centrifugal assembly 19 and the speed limiting housing 11 are arranged as a modular unit at the rear end of the main body of the motor 1, and the counterweight 192, the spring 193, and the inner sleeve 191 are installed on the shaft of the motor 1 as a whole. In this way, when the user installs, the workload is reduced, because there is already a set of pre-assembled modular units, and there is no need to install the electric cylinder and the brake separately. The modular unit is directly added to the rear end of the existing motor 1. In the process of replacing and disassembling the centrifugal assembly 19, the speed limiting housing 11 at the rear end of the main housing 10 is directly disassembled to maintain and replace the centrifugal assembly 19. The two ends of the centrifugal assembly 19 are limited by the retaining ring 16 and the deep groove ball bearing 17, so as to improve the axial stability of the centrifugal assembly 19, better control noise and vibration, and improve the comfort of operation.

[0067] Since the centrifugal assembly 19 is manufactured as a whole, it can be directly added to the rear end of the main body of the motor 1, so only the length of the motor 1 shaft needs to be increased, and no other modifications are required to the main body of the motor 1, and the motor 1 can still be subjected to dynamic balancing test. The motor 1 with a rear centrifugal brake can improve the reliability of the system by reducing the connectors and transmission elements in the transmission chain, thereby reducing the possibility of failure.

[0068] In addition, an O-ring 15 is provided at the connection between the centrifugal assembly 19 and the main casing 10 to prevent powder debris generated by the friction between the counterweight block 192 and the inner wall of the speed limit box casing 11 from entering the electromagnetic brake 141, thereby affecting the opening and closing function of the electromagnetic brake 141, protecting the electromagnetic brake 141, reducing the possibility of failure of the electromagnetic brake 141, and improving the service life of the electromagnetic brake 141.

[0069] 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 motor with a rear centrifugal brake, characterized in that: include, a main housing (10), and A speed limiting housing (11), wherein the speed limiting housing (11) is arranged at the rear end of the main housing (10); A motor shaft (13), the motor shaft (13) being rotatably connected in the main housing (10), and an output end of the motor shaft (13) passing through the main housing (10); A driving assembly (12), wherein the driving assembly (12) is disposed in the main housing (10) and is used to drive the motor shaft (13) to rotate; A centrifugal assembly (19), wherein the centrifugal assembly (19) is arranged in the speed limiting housing (11); The rear end of the motor shaft (13) passes through the main housing (10) and extends into the speed limiting housing (11) to be connected to the centrifugal assembly (19), and the centrifugal assembly (19) brakes the motor shaft (13) through friction with the inner wall of the speed limiting housing (11).

2. The motor of the rear centrifugal brake according to claim 1, characterized in that: The centrifugal assembly (19) comprises a counterweight (192), the counterweight (192) being slidably connected to the motor shaft (13) along the radial direction of the motor shaft (13), the side wall of the counterweight (192) away from the motor shaft (13) having friction and being used to abut against the inner side wall of the speed limiting case (11), and a spring (193) being arranged on the counterweight (192).

3. The motor of the rear centrifugal brake according to claim 2, characterized in that: The centrifugal assembly (19) further comprises an inner sleeve (191), wherein the inner sleeve (191) is coaxially sleeved on the motor shaft (13), and the counterweight (192) is slidably connected to the inner sleeve (191) along the radial direction of the inner sleeve (191).

4. The motor of the rear centrifugal brake according to claim 3, characterized in that: The shape of the side wall of the counterweight (192) that abuts against the inner side wall of the speed limiter housing (11) is adapted to the inner side wall of the speed limiter housing (11).

5. The motor of the rear centrifugal brake according to claim 3, characterized in that: A plurality of the counterweight blocks (192) are provided, and the plurality of counterweight blocks (192) are circumferentially arranged on the outer side wall of the inner shaft sleeve (191).

6. The motor of the rear centrifugal brake according to claim 2, characterized in that: An arc-shaped limiting groove (194) is provided on the end surface of each counterweight block (192), and the limiting grooves (194) on the plurality of counterweight blocks (192) form an annular limiting ring groove. The spring (193) is configured as a closed ring, and the spring (193) is embedded in the limiting ring groove.

7. The motor of the rear centrifugal brake according to claim 5, characterized in that: The front end of the inner shaft sleeve (191) is sealed and connected to the main housing (10) via an O-ring (15).

8. The motor of the rear centrifugal brake according to claim 1, characterized in that: A deep groove ball bearing (17) is arranged between the rear end of the centrifugal component (19) and the speed limiting housing (11), and the deep groove ball bearing is used for press-fitting the centrifugal component (19).

9. The motor of the rear centrifugal brake according to claim 8, characterized in that: A disc spring (18) is installed between the deep groove ball bearing (17) and the speed limiter housing (11).

10. The motor of the rear centrifugal brake according to claim 1, characterized in that: The motor shaft (13) is connected to a retaining spring (16), which is arranged at the front end of the centrifugal assembly (19) and is used to position the centrifugal assembly (19).

11. The motor of the rear centrifugal brake according to claim 2, characterized in that: An electromagnetic clutch is arranged in the main housing (10), and the electromagnetic clutch is used to brake the motor shaft (13).

12. The motor of the rear centrifugal brake according to claim 9, characterized in that: The main housing (10) is provided with a manual release (142), and the manual release (142) is connected to the electromagnetic brake (141).

13. The motor of the rear centrifugal brake according to claim 2, characterized in that: The main housing (10) is provided with a detection meter, which is used to detect the current of the drive component (12) or the rotation speed of the motor shaft (13).

14. A linear actuator, characterized in that: include: Driver (3), and A reducer (2), wherein the reducer (2) is connected to a driver (3); The motor (1) of the post-mounted centrifugal brake according to any one of claims 1 to 13, wherein the motor (1) of the post-mounted centrifugal brake drives the driver (3) via a reducer (2).

15. The linear actuator according to claim 14, characterized in that: The centrifugal component (19) is arranged on a side away from the reducer (2).

16. A lifting platform, characterized in that: The lifting platform is driven by the linear actuator described in claim 15.

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