Overload protection rotary actuator

Abstract

The utility model belongs to the technical field of rotary actuators, and particularly relates to an overload protection rotary actuator. The overload protection rotary actuator comprises a power source located at the upstream end of power, a reduction gear set driven by the power source, a rotary output piece located at the downstream end of the power and used for outputting rotary driving force to an acting object, and a shell. The rotary output piece is rotatably assembled on the shell, and the rotary output piece is provided with a gear ring arranged in the circumferential direction; a transition gear is arranged in the reduction gear set; a clutch rack is connected between the transition gear and the gear ring; the two ends of the clutch rack are limited in the shell to slide linearly, and the middle of the clutch rack is provided with an elastic clutch section with the rigidity smaller than that of the two ends. The transition gear is meshed with the clutch section; when the load between the transition gear and the clutch section exceeds the limit, the clutch section is bent to form decoupling. According to the actuator provided by the utility model, the overload protection capability which is large enough can be ensured, and the size and the cost of the device cannot be obviously increased.

Description

Technical Field

[0001] This utility model belongs to the field of rotary actuator technology, specifically relating to an overload protection rotary actuator. Background Technology

[0002] With the development of smart homes and home appliances, consumers are increasingly demanding higher levels of functionality, intelligence, and safety from these products. This is especially true for smart refrigerators and other home appliances, which are trending towards more compact and aesthetically pleasing designs; for example, built-in refrigerators have very strict space constraints on the top of the refrigerator.

[0003] In these smart home appliances, rotary actuators play a crucial role as core components for key functions such as door opening and closing. However, in practical applications, rotary actuators often face overload situations. For example, when the refrigerator door is obstructed or abnormal resistance is caused by improper user operation, the lack of an effective overload protection mechanism may lead to problems such as motor burnout and gear damage, and in severe cases, may even cause safety accidents, such as pinching a user's fingers. Therefore, developing a rotary actuator that can quickly respond and effectively protect the system under overload conditions is particularly important.

[0004] In existing technologies, electromagnetic clutches are commonly used to interrupt power transmission for overload protection. However, this approach has significant limitations: First, the maximum torque that an electromagnetic clutch can withstand is relatively small. To adapt to high-torque applications, the size of the electromagnetic clutch needs to be increased, which contradicts the current trend of miniaturization in smart home appliances, especially the trend of thin actuators in compact refrigerators. Second, electromagnetic clutches are expensive and have a complex structure, increasing maintenance difficulty. Furthermore, the response speed and sensitivity of electromagnetic clutches are prone to instability after long-term use, affecting the user experience. Utility Model Content

[0005] To address the shortcomings of existing technologies, this utility model provides an overload-protected rotary actuator.

[0006] The purpose of this invention is to provide a solution that can ensure sufficient overload protection without significantly increasing the size and cost of the device, especially for products with strict limitations on installation space, such as zero-embedded refrigerators.

[0007] The overload-protected rotary actuator includes a power source located upstream of the power source, a reduction gear set driven by the power source, a rotary output component located downstream of the power source for outputting rotary driving force to the workpiece, and a housing; the rotary output component is rotatably mounted on the housing and has a circumferentially arranged gear ring; the reduction gear set includes a transition gear; a clutch rack is connected between the transition gear and the gear ring; the two ends of the clutch rack are restricted to slide linearly within the housing, and the middle of the clutch rack has a clutch section with less stiffness than the two ends and is elastic; the transition gear meshes with the clutch section; when the load between the transition gear and the clutch section exceeds the limit, the clutch section bends away from the transition gear, causing the clutch section to decouple from the transition gear.

[0008] As a further optimization of the overload protection rotary actuator, the power source and reduction gear set are installed inside the housing; the rotary output component is rotatably mounted on the housing, with one end of the rotary output component located inside the housing and the other end protruding from the housing; the end of the rotary output component located inside the housing has a circumferentially arranged gear ring.

[0009] As a further optimization of the overload protection rotary actuator, a stop block is provided on the housing and located near the gear ring; one end of the clutch rack is slidably disposed in the channel formed between the stop block and the gear ring; the stop block supports the back of the clutch rack to keep the clutch rack and the gear ring in an engaged state.

[0010] As a further optimization of the overload protection rotary actuator, the abutment has a flat abutment surface on the side adjacent to the gear ring; the abutment surface abuts against the back of the clutch rack, and a lubricating medium is applied between the two.

[0011] As a further optimization of the overload protection rotary actuator, the housing also has a groove, and the end of the clutch rack away from the gear ring slides in the groove.

[0012] As a further optimization of the overload protection rotary actuator, the thickness of the clutch section in the clutch rack is smaller than that at both ends, giving the clutch section relatively low stiffness.

[0013] As a further optimization of the overload protection rotary actuator, the back side of the clutch section in the clutch rack is cut to form a stiffness adjustment groove, so that the clutch section has relatively small stiffness; the stiffness adjustment groove extends along the length direction of the clutch rack.

[0014] As a further optimization of the overload protection rotary actuator, the clutch rack is made of plastic injection molding or metal machining.

[0015] As a further optimization of the overload protection rotary actuator, the power source is a motor; the reduction gear set also includes a worm, a first transmission gear, a second transmission gear, a third transmission gear, and a reduction planetary gear set; the worm is mounted on the motor output shaft; the first transmission gear and the second transmission gear are coaxially connected, and the diameter of the first transmission gear is larger than the diameter of the second transmission gear; the first transmission gear meshes with the worm; the third transmission gear connects between the second transmission gear and the reduction planetary gear set, transmitting the rotational driving force of the second transmission gear to the reduction planetary gear set; the reduction planetary gear set transmits the rotational driving force to the transition gear.

[0016] As a further optimization of the overload protection rotary actuator, the housing has a flattened receiving chamber, in which the power source, worm gear, first transmission gear, second transmission gear, third transmission gear, and reduction planetary gear set are arranged; the outer side of the housing has a recessed area, in which the transition gear and clutch section are arranged.

[0017] Beneficial effects

[0018] Compared with existing technologies, the overload protection rotary actuator provided by this invention can effectively protect the rotary drive system in home appliances from overload damage. When the rotary output component encounters an abnormal load, the elastic clutch section of the rack bends and disengages from the intermediate gear, thereby quickly interrupting power transmission, preventing damage to the motor and reduction gear set due to overload, and reducing the risk of possible impact or pinching injuries to users. Furthermore, because the rack clutch structure occupies very little height and does not increase the overall thickness of the actuator, it can adapt to various space-constrained applications, such as smart refrigerators. In addition, by adjusting the structure of the clutch section, such as changing the stiffness adjustment groove, the trigger point of overload protection can be precisely controlled, and actuators with different overload protection trigger forces can be mass-produced at extremely low cost to adapt to different application scenarios. Attached Figure Description

[0019] Figure 1 A schematic diagram of the overall structure of the rotary actuator for overload protection.

[0020] Figure 2 A schematic diagram of the back of a rotary actuator for overload protection.

[0021] Figure 3 A schematic diagram of the internal structure of a rotary actuator for overload protection.

[0022] Figure 4 for Figure 2 A magnified view of a portion of the image.

[0023] Figure 5 This is a schematic diagram of a clutch rack with a thinning section.

[0024] Figure 6 This is a schematic diagram of a clutch rack with a stiffness adjustment groove.

[0025] Figure 7 This is a partial structural diagram of a reduction gear set.

[0026] Figure 8 and Figure 9 This is a schematic diagram of a planetary gear set for speed reduction.

[0027] Figure 10 This is a top view of the refrigerator.

[0028] Figure 11 This is a magnified view of a portion of the refrigerator's actuator area.

[0029] In the diagram: 1. Power source; 3. Rotary output component; 4. Clutch rack; 9. Housing; 21. Worm gear; 22. First transmission gear; 23. Second transmission gear; 24. Third transmission gear; 25. Reduction planetary gear set; 29. ​​Transition gear; 31. Gear ring; 41. Clutch section; 81. Refrigerator body; 82. Refrigerator door; 91. Stop block; 92. Slide groove. Detailed Implementation

[0030] The present invention is further illustrated by the following embodiments, which are intended to more clearly illustrate the technical solution of the present invention, and should not be construed as a limitation.

[0031] Firstly, overload protection for rotary actuators.

[0032] like Figure 1 and Figure 2 The overload-protected rotary actuator shown includes a power source 1 located upstream of the power source, a reduction gear set driven by the power source 1, a rotary output component 3 located downstream of the power source for outputting rotational driving force to the target object, and a housing 9. The housing 9 serves as a supporting and protective component of the overall structure; the power source 1 provides the initial driving force; the reduction gear set transmits torque and increases torque by reducing the rotational speed through a series of gears; the rotary output component 3 outputs the final rotational force to the target object to drive its rotation, such as the rotatable door of a refrigerator, oven, or other household appliance.

[0033] like Figures 1 to 3As shown, the power source 1 and the reduction gear set are installed inside the housing 9; the rotary output component 3 is rotatably mounted on the housing 9, with one end of the rotary output component 3 located inside the housing 9 and the other end protruding from the housing 9; the end of the rotary output component 3 located inside the housing 9 has a circumferentially arranged gear ring 31. The reduction gear set has a transition gear 29; a clutch rack 4 is connected between the transition gear 29 and the gear ring 31; both ends of the clutch rack 4 are restricted to slide linearly within the housing 9, and the middle of the clutch rack 4 has a clutch section 41 with less stiffness than the two ends and elasticity; the transition gear 29 meshes with the clutch section 41; when the load between the transition gear 29 and the clutch section 41 exceeds the limit, the clutch section 41 bends away from the transition gear 29, causing the clutch section 41 to decouple from the transition gear 29.

[0034] When the actuator is working normally, the clutch rack 4 maintains good meshing with the transition gear 29, allowing power to be smoothly transmitted from the power source 1 to the rotating output component 3. When an abnormal situation occurs that causes excessive load, the clutch section 41 deforms due to its unique low stiffness and elasticity, thereby disengaging from the transition gear 29, releasing the load exceeding the limit, and achieving high-response overload protection. Moreover, this overload protection structure occupies only a very small thickness of the actuator, and will not become a limiting factor for compressing the actuator thickness, thus avoiding excessive actuator thickness that would restrict installation in various household appliances.

[0035] like Figure 3 and Figure 4 As shown, a stop block 91 is provided on the housing 9 and located near the gear ring 31; one end of the clutch rack 4 is slidably disposed in the channel formed between the stop block 91 and the gear ring 31; the stop block 91 supports the back of the clutch rack 4 to keep the clutch rack 4 and the gear ring 31 engaged, and also prevents the clutch rack 4 from being bent and broken by unrestricted bending when the actuator is subjected to excessive load.

[0036] Preferably, the abutment block 91 has a flat abutment surface on the side adjacent to the gear ring 31; the abutment surface abuts against the back of the clutch rack 4, so that the angle of the rack near the gear ring 31 remains consistent.

[0037] Preferably, the contact surface and the contact area between the clutch rack 4 and the back of the clutch rack 4 are coated with a lubricating medium, such as lubricating oil or grease.

[0038] like Figure 2As shown, the housing 9 also has a groove 92, and the end of the clutch rack 4 furthest from the gear ring 31 is slidably engaged in the groove 92. The groove 92 and the stop block 91 restrict the deviation of the clutch rack 4 at both ends, thereby ensuring that the clutch rack 4 can only slide on a predetermined path when subjected to overload bending. In addition, the groove 92 and the stop block 91 restrict the deviation of the clutch rack 4 at both ends, so that the bending of the clutch rack 4 mainly occurs in the clutch section 41. This allows for more precise control of the critical point for overload protection triggering, enabling the actuator to activate the overload protection mechanism under the same load conditions, thereby improving the consistency and reliability of different batches of products.

[0039] In some embodiments, such as Figure 5 As shown, the thickness of the clutch section 41 in the clutch rack 4 is smaller than that at both ends, giving the clutch section 41 relatively low stiffness.

[0040] In some other embodiments, such as Figure 6 As shown, the back side of the clutch section 41 in the clutch rack 4 is cut to form a stiffness adjustment groove, giving the clutch section 41 relatively low stiffness; the stiffness adjustment groove extends along the length of the clutch rack 4. By presetting different depths and widths of the stiffness adjustment groove, a series of clutch racks 4 with different stiffnesses can be mass-produced to correspond to overload protection triggering critical points of different forces, thereby facilitating the mass production of actuators of different specifications to adapt to products with different parameter requirements, such as adapting to refrigerators of different sizes.

[0041] like Figure 2 , Figure 3 , Figure 7 , Figure 8 , Figure 9 As shown, the power source 1 is an electric motor; the reduction gear set also includes a worm 21, a first transmission gear 22, a second transmission gear 23, a third transmission gear 24, and a reduction planetary gear set 25; the worm 21 is mounted on the output shaft of the motor; the first transmission gear 22 and the second transmission gear 23 are coaxially connected, and the diameter of the first transmission gear 22 is larger than the diameter of the second transmission gear 23; the first transmission gear 22 meshes with the worm 21; the third transmission gear 24 is connected between the second transmission gear 23 and the reduction planetary gear set 25, transmitting the rotational driving force of the second transmission gear 23 to the reduction planetary gear set 25; the reduction planetary gear set 25 transmits the rotational driving force to the transition gear 29. The housing 9 has a flattened receiving chamber, in which the power source 1, worm 21, first transmission gear 22, second transmission gear 23, third transmission gear 24, and reduction planetary gear set 25 are arranged; one side of the housing 9 has a recessed area, in which the transition gear 29 and the clutch section 41 are arranged.

[0042] The worm gear 21 and the first transmission gear 22 form the first stage of reduction; the first transmission gear 22 and the second transmission gear 23 form the second stage of reduction; and the planetary gear set 25 forms the third stage of reduction. This achieves a high reduction ratio within a compact space, requiring only a small height. The clutch rack 4 and the reduction gear set are separated to avoid mutual interference and improve operational reliability. Figure 8 , Figure 9 As shown, in the third-stage reduction structure consisting of the planetary gear set 25, the external gear ring remains fixed, the sun gear serves as the input end, and the planet carrier serves as the output end.

[0043] Secondly, overload protection is applied to rotary actuators.

[0044] The aforementioned overload-protected rotary actuators can be widely used in various household appliances. Taking refrigerators as an example, for instance... Figure 10 , Figure 11 As shown, the refrigerator includes a refrigerator body 81 and a refrigerator door 82 rotatably connected to the refrigerator body 81; an overload protection rotary actuator is installed on the top of the refrigerator body 81, and a rotary output component 3 is assembled at the pivot of the refrigerator door 82 to drive the refrigerator door 82 to rotate, thereby driving the refrigerator door 82 to rotate to complete the opening and closing.

[0045] When the refrigerator door 82 is opened or closed normally, the clutch rack 4 maintains good engagement with the transition gear 29, ensuring that power is smoothly transmitted from the power source 1 to the rotary output component 3. However, if the refrigerator door 82 encounters an obstacle or experiences abnormal resistance leading to excessive load, the clutch section 41 in the clutch rack 4 will bend due to overload, causing the clutch rack 4 to slip and decouple from the transition gear 29. This prevents damage to the power source 1 and the reduction gear set due to overload, and also prevents accidental injury to the user. Once the overload situation is relieved, the clutch rack 4 will immediately re-engage, continuing to support the normal operation of the refrigerator door 82.

[0046] Additionally, it should be noted that the top of the refrigerator body 81 of this type of smart refrigerator is usually equipped with a protective cover (not shown) to house the actuator, preventing the actuator structure from being directly exposed and improving operational reliability.

[0047] The above embodiments are exemplary and are intended to illustrate the technical concept and features of this utility model, so that those skilled in the art can understand the content of this utility model and implement it accordingly. They should not be construed as limiting the scope of protection of this utility model. All equivalent changes or modifications made in accordance with the spirit and essence of this utility model should be included within the scope of protection of this utility model.

Claims

1. An overload-protected rotary actuator, characterized by: The application relates to a power transmission device, which comprises a power source (1) located at an upstream end of power, a reduction gear set driven by the power source (1), a rotary output member (3) for outputting rotary driving force to an acting object located at a downstream end of power, and a housing (9); the rotary output member (3) is rotatably assembled on the housing (9), and the rotary output member (3) has a gear ring (31) arranged in a circumferential direction; the reduction gear set has a transition gear (29); a clutch rack (4) is connected between the transition gear (29) and the gear ring (31); two ends of the clutch rack (4) are limited to slide in a straight line in the housing (9), and the clutch rack (4) has a clutch section (41) with a smaller rigidity than two ends and with elasticity in a middle part; the transition gear (29) is engaged with the clutch section (41); when a load between the transition gear (29) and the clutch section (41) exceeds a limit, the clutch section (41) is bent away from the transition gear (29) to cause the clutch section (41) to be decoupled from the transition gear (29).

2. The overload-protected rotary actuator of claim 1, wherein: A stop block (91) is arranged on the housing (9) and located close to the gear ring (31); one end of the clutch rack (4) is slidably arranged in a channel formed between the stop block (91) and the gear ring (31); the stop block (91) supports a back surface of the clutch rack (4) to keep the clutch rack (4) engaged with the gear ring (31).

3. The overload-protected rotary actuator of claim 2, wherein: The stop block (91) has a flat abutting surface on a side close to the gear ring (31); the abutting surface is abutted with the back surface of the clutch rack (4), and lubricating medium is attached between the abutting surface and the back surface.

4. The overload protection rotary actuator of claim 2, wherein: The housing (9) further has a sliding groove (92), and one end of the clutch rack (4) away from the gear ring (31) is slidably arranged in the sliding groove (92).

5. An overload protection rotary actuator according to any one of claims 1 to 4, characterized in that: The thickness of the clutch section (41) in the clutch rack (4) is smaller than that of two ends, so that the clutch section (41) has a relatively small rigidity.

6. An overload protection rotary actuator according to any one of claims 1 to 4, characterized in that: The back side of the clutch section (41) in the clutch rack (4) is cut to form a rigidity adjusting groove, so that the clutch section (41) has a relatively small rigidity; the rigidity adjusting groove extends along the length direction of the clutch rack (4).

7. An overload protection rotary actuator according to any one of claims 1 to 4, characterized in that: The clutch rack (4) is a plastic injection molding part or a metal machining part.

8. An overload protection rotary actuator according to any one of claims 1 to 4, characterized in that: The power source (1) is an electric motor; the reduction gear set further comprises a worm (21), a first transmission gear (22), a second transmission gear (23), a third transmission gear (24), a reduction planetary gear set (25); the worm (21) is installed on the output shaft of the electric motor; the first transmission gear (22) is coaxially connected with the second transmission gear (23), and the diameter of the first transmission gear (22) is greater than that of the second transmission gear (23); the first transmission gear (22) is engaged with the worm (21); the third transmission gear (24) is connected between the second transmission gear (23) and the reduction planetary gear set (25), and transmits the rotating driving force of the second transmission gear (23) to the reduction planetary gear set (25); the reduction planetary gear set (25) transmits the rotating driving force to the transition gear (29).

9. The overload-protected rotary actuator of claim 8, wherein: The housing (9) has a flat accommodating cavity inside, and the power source (1), the worm (21), the first transmission gear (22), the second transmission gear (23), the third transmission gear (24), and the reduction planetary gear set (25) are arranged in the accommodating cavity; one side of the housing (9) has a recessed area, and the transition gear (29) and the clutch section (41) are arranged in the recessed area.

Images