Bidirectional overrunning clutch and mobile robot with same

Abstract

The utility model discloses a bidirectional overrunning clutch and a mobile robot with the bidirectional overrunning clutch, and the bidirectional overrunning clutch comprises a driving shaft which is provided with a driving section with a polygonal longitudinal section; the retainer comprises a plurality of mounting blocks which are arranged around the driving shaft, mounting holes are formed in the mounting blocks, and every two adjacent mounting blocks are connected through an elastic piece which enables the two adjacent mounting blocks to have a tendency to be close to each other to apply pressure to the mounting blocks; the pin rollers and the driving shaft are arranged side by side in the same direction and are rotationally arranged in the mounting holes; the driven shaft is provided with an inner hole and is arranged outside the retainer in a sleeving manner, and the inner wall of the inner hole is provided with a plurality of meshing grooves used for being meshed with the pin rollers; the drive section has a maximum radial dimension H and a minimum radial dimension h, the roller has a diameter d, the inner bore has a maximum inner radius R and a minimum inner radius r, H + d > 2R, and h + d < 2r. The bidirectional clutch of the driving shaft relative to the driven shaft can be realized, and the driven shaft can be prevented from reversely driving the driving shaft to rotate.

Description

Technical Field

[0001] The present application relates to the technical field of mechanical transmission components, and in particular to a bidirectional overrunning clutch and a mobile robot having the same. Background Art

[0002] The overrunning clutch is a basic mechanical transmission component in mechatronic products, mainly used for power transmission and separation between the prime mover and the working machine or between the driving shaft and the driven shaft inside the machine. It is a self-controlled clutch that uses the speed change or rotation direction change of the active and driven parts or the transmission characteristics of certain parts to achieve the self-clutching function. According to the working principle, the overrunning clutch can generally be divided into a wedge-type overrunning clutch, a ball-type overrunning clutch and a ratchet-type overrunning clutch. However, most of the overrunning clutches in the related art cannot achieve the function of two-way clutching (that is, the driving shaft can drive the driven shaft to rotate clockwise or counterclockwise). In addition, the overrunning clutch in the related art cannot achieve the function of idling of the driven shaft, that is, when the driven shaft rotates, it will drive the driving shaft to rotate in the opposite direction, which will affect the use of electromechanical in some application scenarios. Utility Model Content

[0003] The present application aims to solve one of the technical problems in the related art to a certain extent. To this end, the present application provides a two-way overrunning clutch and a mobile robot having the same.

[0004] In order to achieve the above-mentioned purpose, the present application adopts the following technical solution: a two-way overrunning clutch, comprising:

[0005] A driving shaft having a driving section with a polygonal longitudinal section;

[0006] A retainer, comprising a plurality of mounting blocks arranged around the driving shaft, the mounting blocks being provided with mounting holes penetrating the mounting blocks in the radial direction of the driving shaft, two adjacent mounting blocks being connected by elastic members, and the elastic members applying pressure to the mounting blocks so that the two adjacent mounting blocks have a tendency to approach each other;

[0007] a roller, which is arranged side by side with the driving shaft in the same direction and rotatably disposed in the mounting hole; and

[0008] A driven shaft having an inner hole and sleeved outside the retaining frame, wherein the inner wall of the inner hole is provided with a plurality of meshing grooves for meshing with the rollers, and the plurality of meshing grooves are evenly distributed along the circumference of the inner hole;

[0009] The driving section has a maximum radial dimension H and a minimum radial dimension h, the roller has a diameter d, and the inner hole has a maximum inner radius R and a minimum inner radius r, wherein H+d>2R, h+d<2r.

[0010] The application of the present invention has the following beneficial effects: by designing a driving section on the driving shaft, the longitudinal section of the driving section is polygonal, so that the driving section can have a maximum radial dimension H and a minimum radial dimension h, and by designing the dimensions of the driving section, the roller and the inner hole of the driven shaft, H+d>2R, h+d<2r. Since h+d<2r, when the driving shaft is not rotating, the roller is relatively separated from the meshing groove, and the rotation of the driven shaft cannot drive the driving shaft to rotate in the reverse direction; and since H+d>2R, when the driving shaft rotates forward or reversely, the cage can be driven to rotate by rotation, and the centrifugal force on the cage during rotation and the force of the driving shaft on the cage and the roller can be used to make the roller mesh into the meshing groove, thereby driving the driven shaft to rotate.

[0011] Optionally, the longitudinal section of the driving section is an octagon, and the octagon has four long sides and four short sides arranged in an alternating manner, the distance between two opposite short sides is the maximum radial dimension H, and the distance between two opposite long sides is the minimum radial dimension h.

[0012] Optionally, the mounting block is provided with a through hole along the axial direction of the driving shaft, a rotating shaft is provided in the through hole, and the roller is rotatably arranged in the mounting hole via the rotating shaft.

[0013] Optionally, the elastic member is disposed at both the front end and the rear end of the mounting block in the axial direction of the driving shaft.

[0014] Optionally, the elastic member is a spring, a connecting member is provided on the mounting block, and two ends of the spring are respectively fixedly connected to the connecting members on two adjacent mounting blocks.

[0015] Optionally, the engagement grooves are distributed along the circumference of the inner hole.

[0016] Optionally, the driving shaft also includes a first connecting section and a second connecting section respectively located on both sides of the driving section and coaxial with the driving section, the longitudinal cross-sections of the first connecting section and the second connecting section are both circular, and the maximum diameter dimensions of the first connecting section and the second connecting section are not greater than the minimum radial dimension h of the driving section.

[0017] Optionally, bearings are disposed outside the first connecting section and the second connecting section, and the driven shaft sleeve is disposed outside the bearings.

[0018] Optionally, a resistance structure is provided between the retaining frame and the driven shaft, and the resistance structure is used to limit the retaining frame from rotating along with the driven shaft at the moment when the driving shaft starts to rotate.

[0019] Optionally, the resistance structure is a friction ring disposed between the outer surface of the mounting block and the inner wall of the inner hole, and the friction ring is fixedly disposed on the outer surface of the mounting block or the inner wall of the inner hole.

[0020] In addition, to solve the above-mentioned technical problems, the present application also provides a mobile robot, comprising a mobile chassis and a driving motor for driving the mobile chassis to move, the mobile robot also comprising a two-way overrunning clutch as described in any one of the above-mentioned technical solutions, wherein the driving shaft is connected to the output end of the driving motor, and the driven shaft is connected to the mobile chassis.

[0021] These features and advantages of the present application will be disclosed in detail in the following specific embodiments and drawings. The best embodiments or means of the present application will be described in detail in conjunction with the drawings, but they are not intended to limit the technical solutions of the present application. In addition, there are multiple features, elements, and components that appear in each of the following texts and drawings, and different symbols or numbers are marked for convenience, but they all represent components with the same or similar structures or functions. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present application is further described below in conjunction with the accompanying drawings:

[0023] Figure 1 A schematic diagram of the structure of a bidirectional overrunning clutch provided in an embodiment of the present application;

[0024] Figure 2 An exploded view of the bidirectional overrunning clutch provided in an embodiment;

[0025] Figure 3 An exploded view of the bidirectional overrunning clutch provided in an embodiment from another perspective;

[0026] Figure 4 An overall cross-sectional view of the bidirectional overrunning clutch provided in an embodiment;

[0027] Figure 5 A cross-sectional view of the bidirectional overrunning clutch provided in the embodiment when the roller is engaged with the engagement groove;

[0028] Figure 6 A cross-sectional view of the bidirectional overrunning clutch provided in an embodiment when the roller is separated from the meshing groove;

[0029] Figure 7 A schematic cross-sectional view of a driving section in the bidirectional overrunning clutch provided in an embodiment;

[0030] Figure 8 A schematic cross-sectional view of a driven shaft in the bidirectional overrunning clutch provided in an embodiment;

[0031] Fig. 9 An exploded view of the retaining frame in the bidirectional overrunning clutch provided in an embodiment.

[0032] Among them, 1. driving shaft, 10. driving section, 11. first connecting section, 12. second connecting section, 2. retaining frame, 20. mounting block, 200. mounting hole, 201. through hole, 202. connecting piece, 3. elastic piece, 4. roller, 40. rotating shaft, 5. driven shaft, 50. meshing groove, 6. bearing. DETAILED DESCRIPTION

[0033] The embodiments of the present application are described in detail below, and 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 with the same or similar functions. The embodiments based on the embodiments are intended to be used to explain the present application and cannot be understood as limiting the present application.

[0034] References to "one embodiment" or "an example" or "an example" in this specification mean that a particular feature, structure, or characteristic described in conjunction with the embodiment itself may be included in at least one embodiment disclosed in the present application. The appearance of the phrase "in one embodiment" in various places in the specification does not necessarily refer to the same embodiment.

[0035] Embodiment: This embodiment provides a two-way overrunning clutch, such as Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown in , the two-way overrunning clutch comprises a driving shaft 1, a retainer 2, an elastic member 3, a roller 4 and a driven shaft 5. The driving shaft 1 has a driving section 10 with a polygonal longitudinal section, and the retainer 2 comprises a plurality of mounting blocks 20 arranged around the driving shaft 1, and the mounting blocks 20 are provided with mounting holes 200 that penetrate the mounting blocks 20 in the radial direction of the driving shaft 1. Two adjacent mounting blocks 20 are connected by an elastic member 3, and the elastic member 3 applies pressure to the mounting blocks 20 so that the two adjacent mounting blocks 20 have a tendency to approach each other. The roller 4 is arranged side by side in the same direction as the driving shaft 1 and is rotatably arranged in the mounting hole 200. Through the action of the elastic member 3, the plurality of mounting blocks 20 surrounding the driving shaft 1 are surrounded by a certain force outside the driving shaft 1, so that when the driving shaft 1 rotates, the retainer 2 will rotate with the driving shaft 1; at the same time, when the retainer 2 reaches a certain speed, under the action of centrifugal force, the adjacent mounting blocks 20 will overcome the force of the elastic member 3 and open radially outward relative to the driving shaft 1. Correspondingly, the driven shaft 5 has an inner hole and is sleeved outside the cage 2. The inner wall of the inner hole is provided with a plurality of meshing grooves 50 for meshing with the rollers 4. The plurality of meshing grooves 50 are evenly distributed along the circumference of the inner hole. Thus, when the cage 2 is expanded outward, the rollers 4 on the cage 2 can enter the meshing grooves 50 and mesh with the meshing grooves 50, so that the power of the driving shaft 1 can be transmitted to the driven shaft 5, so that the driving shaft 1 can rotate forward or reverse to drive the driven shaft 5 to rotate.

[0036] Combination Figure 5 , Figure 6 , Figure 7 and Figure 8 As shown in, as mentioned above, the driving shaft 1 in this embodiment has a driving section 10 with a polygonal longitudinal section, the driving section 10 has a maximum radial dimension H and a minimum radial dimension h, and the inner hole has a maximum inner radius R (the spacing between the bottoms of the two opposite meshing grooves 50 is 2R) and a minimum inner radius r (the spacing between the ends of the two opposite meshing grooves 50 is 2r). The driving section 10 has a roller 4 with a diameter d. The dimensions of the driving section 10, the inner hole and the roller 4 satisfy the following relationship: H+d>2R, h+d<2r.

[0037] By designing the driving section 10 on the driving shaft 1, the longitudinal section of the driving section 10 is polygonal, so that the driving section 10 can have a maximum radial dimension H and a minimum radial dimension h, and by designing the dimensions of the driving section 10, the roller 4 and the inner hole of the driven shaft 5, H+d>2R, h+d<2r. Since h+d<2r, when the driving shaft 1 is not rotating, the roller 4 is relatively separated from the meshing groove 50, and the rotation of the driven shaft 5 cannot drive the driving shaft 1 to rotate in the reverse direction; and since H+d>2R, when the driving shaft 1 rotates forward or reversely, the cage 2 can be driven to rotate by rotation, and the centrifugal force on the cage 2 during rotation and the force of the driving shaft on the cage 2 and the roller 4 can be used to make the roller 4 mesh with the meshing groove 50, thereby driving the driven shaft 5 to rotate.

[0038] It should be noted that, in this embodiment, the meshing grooves 50 are distributed along the circumference of the inner hole. In an optional embodiment, a certain number of meshing grooves 50 may be provided but not distributed along the circumference of the inner hole.

[0039] When the two-way overrunning clutch is applied, at the moment when the driving shaft 1 starts to rotate, the retaining frame 2 is clamped to the outside of the driving shaft 1 with a certain force through the action of the elastic member 3. In this way, the retaining frame 2 and the roller 4 on the retaining frame 2 will rotate with the driving shaft 1. However, when the rotation speed of the driving shaft 1 reaches a certain value, under the action of centrifugal force, the mounting block 20 will overcome the elastic force of the elastic member 3 and be pushed outward relative to the driving shaft 1. This creates a speed difference between the retaining frame 2 and the driving shaft 1, and then the driving shaft 1 will rotate circumferentially relative to the roller 4. Due to the aforementioned dimensional design, the driving shaft 1 will pressurize the roller 4 so that the roller 4 and the mounting block 20 will further overcome the elastic force of the elastic member 3 and be pushed outward relative to the driving shaft 1. The final result is as follows Figure 6, the roller 4 is embedded in the meshing groove 50, so that the roller 4 and the meshing groove 50 are meshed, and the driven shaft 5 is driven by the driving shaft 1 to rotate. When the driving shaft 1 stops rotating, under the elastic force of the elastic member 3, the mounting block 20 brings the roller 4 back to its original position, so that the roller 4 is separated from the meshing groove 50, and the driven shaft 5 is driven by the driving shaft 1 to rotate. Figure 5 In this state, even if the external driven shaft 5 rotates, it cannot drive the driving shaft 1 to rotate in the opposite direction.

[0040] The roller 4 overcomes the pulling force between the springs and moves in the circumferential direction under the combined effect of its own centrifugal force and the centrifugal force of the cage 2. At the same time, due to the gap between the roller 4 and the driving shaft 1, when the driving shaft 1 rotates, there is a speed difference between the two. At this time, the polygonal structure of the driving shaft 1 further forces the roller 4 to "embed" the corresponding groove position of the driven shaft 5, thereby achieving the purpose of meshing transmission. Figure 4 When the speed of the driving shaft 1 decreases to a certain level or stops rotating, under the action of the spring force, the roller 4 / cage 2 is out of contact with the groove of the driven shaft 5 and moves to the minimum margin of the driving shaft 1. At this time, the driven shaft 5 can achieve free rotation, i.e., idling.

[0041] Specifically in this embodiment, Figure 7 As shown in , the longitudinal section of the driving section 10 in the two-way overrunning clutch is an octagon, and the octagon has four long sides and four short sides arranged in a staggered manner, and the staggered arrangement means that both sides of each long side are short sides, and both sides of each short side are long sides. Among them, the spacing between two opposite short sides is the maximum radial dimension H, and the spacing between two opposite long sides is the minimum radial dimension h. Correspondingly, four rollers 4 are provided in this embodiment. It is easy to understand that in other optional embodiments, the longitudinal section of the driving section 10 can also be designed as a polygon with other numbers of sides, such as a hexagon or a decagon, etc., and the number of rollers 4 can be changed accordingly.

[0042] Combination Fig. 9 As shown in , the mounting block 20 in this embodiment is provided with a through hole 201 along the axial direction of the driving shaft 1, and a rotating shaft 40 is provided in the through hole 201, and the roller 4 is rotatably provided in the mounting hole 200 through the rotating shaft 40. The rotating shaft 40 can be installed in the through hole 201 with a tight fit, and the roller 4 is correspondingly rotatably connected to the rotating shaft 40; or the roller 4 can be installed in the rotating shaft 40 with a tight fit, and the rotating shaft 40 is correspondingly rotatably connected to the through hole 201. In addition, the mounting block 20 in this embodiment is provided with the aforementioned elastic member 3 at the front end and the rear end along the axial direction of the driving shaft 1. Specifically, the elastic member 3 is a spring, and a connecting member 202 is provided on the mounting block 20, and the two ends of the spring are respectively fixedly connected to the connecting members 202 on two adjacent mounting blocks 20.

[0043] Four mounting blocks 20 are also provided in this embodiment. Generally, the number of mounting blocks 20 is set to be the same as the number of rollers 4. The connecting member 202 in this embodiment is a screw. During assembly, the screw is tightened on the front and rear ends of the mounting block 20 to fix the two ends of the spring to the screws on the two adjacent mounting blocks 20. Optionally, a fixing pin or the like may also be used as the connecting member 202.

[0044] like Figure 3 As shown in , the driving shaft 1 in this embodiment also includes a first connecting section 11 and a second connecting section 12 respectively located on both sides of the driving section 10 and coaxial with the driving section 10, the longitudinal sections of the first connecting section 11 and the second connecting section 12 are both circular, and the maximum diameters of the first connecting section 11 and the second connecting section 12 are not greater than the minimum radial dimension h of the driving section 10. Further, bearings 6 are provided outside the first connecting section 11 and the second connecting section 12, and the driven shaft 5 is sleeved outside the bearings 6. By providing the bearings 6, the driving shaft 1 and the driven shaft 5 can be prevented from relative movement in the radial direction.

[0045] As mentioned above, when the two-way overrunning clutch provided in this embodiment is used, the centrifugal force can be used to cause the mounting block 20 to move outward only after the rotation speed of the driving shaft 1 reaches a certain value. If it is necessary to achieve the clutch of the roller 4 and the meshing groove 50 when the driving shaft 1 rotates at a low speed, it can also be achieved by improving the design based on the above structure. In an optional embodiment, a resistance structure can also be set between the retaining frame 2 and the driven shaft 5, and the resistance structure is used to limit the retaining frame 2 from rotating with the driving shaft 1 at the moment when the driving shaft 1 starts to rotate. By setting it in this way, at the moment when the driving shaft 1 starts to rotate, due to the existence of the resistance structure, the retaining frame 2 will not rotate with the driving shaft 1, so that a speed difference can be caused between the retaining frame 2 and the driving shaft 1 without the action of centrifugal force. In this way, the driving section 10 of the driving shaft 1 can abut against and press the roller 4 and drive the roller 4 to expand outward until it engages with the meshing groove 50.

[0046] Specifically, the resistance structure is a friction ring disposed between the outer surface of the mounting block 20 and the inner wall of the inner hole, and the friction ring can be fixedly disposed on the outer surface of the mounting block 20 or on the inner wall of the inner hole. The friction ring can be made of rubber, plastic or metal, and convex points can be disposed on its surface to obtain the required friction force.

[0047] The two-way overrunning clutch can be applied to a mobile robot, and the mobile robot can be used for tasks such as transporting materials and guiding travel. The mobile robot includes a mobile chassis, a driving motor for driving the mobile chassis to move, and the two-way overrunning clutch, wherein the driving shaft in the two-way overrunning clutch is connected to the output end of the driving motor, and the driven shaft in the two-way overrunning clutch is connected to the mobile chassis. In this way, the power of the driving motor can be transmitted to the mobile chassis through the two-way overrunning clutch to drive the mobile chassis to move. The connection described here can refer to either a direct connection or a connection through a common transmission mechanism.

[0048] The above are only specific embodiments of the present application, but the protection scope of the present application is not limited thereto. Those skilled in the art should understand that the present application includes but is not limited to the contents described in the drawings and the above specific embodiments. Any modification that does not deviate from the functional and structural principles of the present application will be included in the scope of the claims.

Claims

1. A two-way overrunning clutch, characterized in that: include: A driving shaft (1) having a driving section (10) with a polygonal longitudinal section; A retaining frame (2), comprising a plurality of mounting blocks (20) arranged around the driving shaft (1), the mounting blocks (20) being provided with mounting holes (200) penetrating the mounting blocks (20) in a radial direction of the driving shaft (1), two adjacent mounting blocks (20) being connected via an elastic member (3), and the elastic member (3) applying pressure to the mounting blocks (20) so that the two adjacent mounting blocks (20) have a tendency to approach each other; a roller (4), which is arranged side by side with the driving shaft (1) in the same direction and rotatably disposed in the mounting hole (200); and A driven shaft (5) having an inner hole and sleeved outside the retaining frame (2), wherein the inner wall of the inner hole is provided with a plurality of meshing grooves (50) for meshing with the rollers (4), and the plurality of meshing grooves (50) are evenly distributed along the circumference of the inner hole; The driving section (10) has a maximum radial dimension H and a minimum radial dimension h, the roller (4) has a diameter d, and the inner hole has a maximum inner radius R and a minimum inner radius r, wherein H+d>2R, h+d<2r.

2. The two-way overrunning clutch according to claim 1, characterized in that: The longitudinal section of the driving section (10) is an octagon, and the octagon has four long sides and four short sides arranged in a staggered manner, the distance between two opposite short sides is the maximum radial dimension H, and the distance between two opposite long sides is the minimum radial dimension h.

3. The two-way overrunning clutch according to claim 1 or 2, characterized in that: The mounting block (20) is provided with a through hole (201) along the axial direction of the driving shaft (1), a rotating shaft (40) is provided in the through hole (201), and the roller (4) is rotatably arranged in the mounting hole (200) via the rotating shaft (40).

4. The two-way overrunning clutch according to claim 1 or 2, characterized in that: Along the axial direction of the driving shaft (1), the front end and the rear end of the mounting block (20) are both provided with the elastic member (3).

5. The two-way overrunning clutch according to claim 4, characterized in that: The elastic member (3) is a spring, and a connecting member (202) is provided on the mounting block (20), and two ends of the spring are respectively fixedly connected to the connecting members (202) on two adjacent mounting blocks (20).

6. The two-way overrunning clutch according to claim 1 or 2, characterized in that: The engagement grooves (50) are distributed along the circumference of the inner hole.

7. The two-way overrunning clutch according to claim 1 or 2, characterized in that: The driving shaft (1) further comprises a first connecting section (11) and a second connecting section (12) respectively located on both sides of the driving section (10) and coaxial with the driving section (10); the longitudinal sections of the first connecting section (11) and the second connecting section (12) are both circular, and the maximum diameters of the first connecting section (11) and the second connecting section (12) are not greater than the minimum radial dimension h of the driving section (10).

8. The two-way overrunning clutch according to claim 7, characterized in that: Bearings (6) are disposed outside the first connecting section (11) and the second connecting section (12), and the driven shaft (5) is sleeved outside the bearings (6).

9. The two-way overrunning clutch according to claim 1 or 2, characterized in that: A resistance structure is provided between the retaining frame (2) and the driven shaft (5), and the resistance structure is used to limit the retaining frame (2) from rotating following the driven shaft (5) at the moment when the driving shaft (1) starts to rotate.

10. The two-way overrunning clutch according to claim 9, characterized in that: The resistance structure is a friction ring arranged between the outer surface of the mounting block (20) and the inner wall of the inner hole, and the friction ring is fixedly arranged on the outer surface of the mounting block (20) or the inner wall of the inner hole.

11. A mobile robot, comprising a mobile chassis and a driving motor for driving the mobile chassis to move, characterized in that: The mobile robot further comprises a bidirectional overrunning clutch as claimed in any one of claims 1 to 10, wherein the driving shaft (1) is connected to the output end of the driving motor, and the driven shaft (5) is connected to the mobile chassis.

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