Structure of one-way bearing

[0001] The present invention relates to the technical field of bearings, and more particularly to a lightweight structure of one-way bearing that can effectively reduce the weight of the one-way bearing without affecting the strength for power transmission and further has the effect of easy machinability and reduction of manufacturing costs.

[0002] A prior art one-way bearing is shown in FIGS. 1 and 2, and the one-way bearing 10 is arranged between an input member 20 and an output member 30 so as to utilize the one-way bearing 10 to allow the input member 20 to selectively drive the output member 30 in a one-way manner, wherein the one-way bearing 10 comprises a transmission ring 11, and a circumference of the transmission ring 11 that corresponds to the input member 20 is formed with a plurality of equidistant receptacles 12. Two ends of an inside bottom surface of each or the receptacles 12 is respectively formed with a shallow trough portion 121 and a deep trough portion 122, and a roller 15 is disposed in the receptacle 12, and further, the receptacle 12 is provided with an elastic element 16 therein between the roller 15 and the deep trough portion 122 corresponding thereto, so as to bring the rollers 15 in the quickest way toward the shallow trough portion 121 for clamping and inducing one-way driving. An outer circumference of the transmission ring 11 is formed with a plurality of equidistant semi-circular pin notches 18, which mate with a plurality of positioning pins 19 to fulfill an effect of constraining the output member 30.

[0003] The known one-way bearing 10 described above is a one-piece structure. To prevent undesired influence on the resistance for transmission, it needs to machine the transmission ring 11 for assembling the rollers 15 therewith, and it is also necessary that the rollers 15 be in direct contact with the input member 20 to generate a transmission force toward the output member 30. As such, in order to enhance the strength of the transmission ring 11 of the one-way bearing 10 for bearing the resistance and to prevent fracturing and breaking, it is necessary to increase the thickness of the transmission ring 11. This inevitably increases the overall weight and the difficulty of machining, making it contrary to the trend of lightweight designs. Further, the one-way bearing 10 uses the semi-circular pin notches 18 and the positioning pins 19, which are generally small in diameter, to generate the effect of constraining to the output member 30, and this makes it hard to persistently bear the output force for transmission. Long term operation may result in fracture of the positioning pins 19 or breaking of the transmission ring 11, and thus affecting the life span thereof.

[0004] In other words, the existing one-way bearing is imperfect with respect to the structural design thereof and suffers problems of being not easy to reduce the weight and insufficiency of bearing force. Thus, further improvement is necessary. To solve such problems is what the present invention aims for.

[0005] Therefore, the primary objective of the present invention is to reduce the weight through change of material and to increase the area of resistance strength so as to be not easily fractured or broken and effectively extend the life span.

[0006] Further, the secondary objective of the present invention is to effectively achieve the purposes of being light weight and having a small occupation area, without affecting the strength for power transmission, so as to achieve the purposes of easy machinability and reduction of cost.

[0013] As shown in FIGS. 3, 4, and 5, the present invention provides a one-way bearing 50 that is applicable between an input member 80 and an output member 90. The one-way bearing 50 comprises a plastic mounting base 60, a plurality of rollers 65, and a metallic transmission base 70 and allows the input member 80 to selectively drive the output member 90 to move toward a driving side in a one-way manner.

[0014] A detailed structure of the one-way bearing 50 may refer to FIGS. 3, 4, and 5, wherein the plastic mounting base 60 is made through injection molding of plastics, and the plastic mounting base 60 comprises a plurality of equidistant radially-penetrating mounting recesses 61. The mounting recesses 61 respectively receive the rollers 65 to dispose therein. The mounting recesses 61 each have two opposite inside surfaces each of which forms a concave arc surface 62 corresponding to a circumference of the rollers 65 to increase an operation space for the rollers 65. One inside surface of the two opposite inside surfaces of each of the mounting recesses 61 that corresponds to a non-clamping-operation side of the respective roller 65 is formed with a stepped notch 63, which receives therein an elastic element 66 that biasingly pushes an outer circumference of the roller 65. Further, one side of the two opposite inside surfaces of the mounting recesses 61 of the plastic mounting base 60 that corresponds to the metallic transmission base 70 is formed with a first retention curved surface 64 for combining and positioning the plastic mounting base 60 and the metallic transmission base 70. The input member 80 is arranged at one side of the plastic mounting base 60 that is opposite to the metallic transmission base 70, so that the input member 80 is settable in contact with and thus driving the rollers 65 received in the plastic mounting base 60 for operation.

[0015] The metallic transmission base 70 is made of a metal material that possesses resistance. The metallic transmission base 70 is arrangeable on the inner circumference or the outer circumference of the plastic mounting base 60, and the metallic transmission base 70 being arranged at the outer circumference of the plastic mounting base 60, with the input member 80 being arranged at the inner circumference of the plastic mounting base 60, is adopted as a primary embodiment of the present invention. A surface of the metallic transmission base 70 that corresponds to the plastic mounting base 60 is formed, along a circumference thereof, with a plurality of transmission slopes 71 to respectively correspond to the mounting recesses 61, and as shown in FIG. 5, each of the transmission slopes 71 has two ends, of which one corresponding to a non-driving side is formed with a deep trough portion 72, while one end that corresponds to a driving side is formed with a shallow trough portion 73, so that when operation of the input member 80 causes the rollers 65 to move to the shallow trough portions 73 of the transmission slope 71, an effect of tightly clamping and driving may be induced (as shown in FIG. 6). Oppositely, when operation of the input member 80 causes the rollers 65 to move to the deep trough portions 72 of the transmission slope 71, an effect of free rotation may be induced (as shown in FIG. 5). Between the shallow trough portion 73 and the deep trough portion 72 of adjacent transmission slopes 71 of the metallic transmission base 70, a second retention curved surface 74 is formed to correspond to the first retention curved surface 64 of the plastic mounting base 60 for combining and retaining the metallic transmission base 70 and the plastic mounting base 60 in position with respect to each other. A circumference of the metallic transmission base 70 that corresponds to the output member 90 is formed with at least one first retaining engagement surface 75, and a corresponding circumference of the output member 90 is formed with a second retaining engagement surface 95 corresponding to the first retaining engagement surface 75, so as to allow the metallic transmission base 70 drives the output member 90 to move in synchronization therewith and increase an area of resistance between the metallic transmission base 70 and the output member 90.

[0016] In this way, the plastic mounting base 60 uses the rollers 65 to be selectively tightened to the metallic transmission base 70 in a one-way manner, allowing the input member 80 to develop an effect of one-way driving relative to the output member 90 by means of the one-way bearing 50, and a structure of one-way bearing that is lightweight and not easy to damage is constructed.

[0017] Operation of the structure of one-way bearing according to the present invention will be discussed with reference to FIGS. 5 and 6. When the input member 80 rotates in a direction opposite to the driving side (such as stationary or clockwise), the rollers 65 of the plastic mounting base 60 of the one-way bearing 50 are correspondingly located at the deep trough portions 72 of the transmission slopes 71 of the metallic transmission base 70, so that the plastic mounting base 60 cannot drive the metallic transmission base 70 through the rollers 65, and therefore, a state of free rotation is established between the input member 80 and the output member 90.

[0018] When the input member 80 rotates in a direction toward the driving side (such as counterclockwise), the rollers 65 of the plastic mounting base 60 are driven to move in synchronization therewith, so that the rollers 65 are moved to the shallow trough portions 73 of the transmission slopes 71 of the metallic transmission base 70, making the input member 80 and the transmission slopes 71 of the metallic transmission base 70 tightly clamp the rollers 65 therebetween, and therefore, the input member 80 is allowed to drive, in a one-way manner, the output member 90 to move through the one-way bearing 50.

[0019] With the previous arrangement and description, the structure of one-way bearing according to the present invention includes the plastic mounting base 60 that is molded to form a plurality of equidistant and radially-penetrating mounting recesses 61, and the mounting recesses 61 respectively receive the rollers 65 to dispose therein. Further, the surface of the circumference of the metallic transmission base 70 that corresponds to the plastic mounting base 60 is formed with a plurality of transmission slopes 71 respectively corresponding to the mounting recesses 61, so that the rollers 65 arranged on the plastic mounting base 60 may utilize the oppositely arranged metallic transmission base 70 to induce an effect of one-way driving and, in addition, the plastic mounting base 60 being made of plastics may help reduce the weight, and the metallic transmission base 70 includes the first retaining engagement surface 75 that can help increase the area of resistance strength, making it hard to fracture or break, thereby effectively extending the life span thereof, and achieving the purpose of weight reduction without affecting the strength for power transmission, and can further possess advantages of easy machining and cost reduction to significantly improve the utilization thereof.