1. Technical Field
The present disclosure relates generally to magnetic gears, more particularly, to a magnetic gear for a transmission mechanism.
2. Description of Related Art
A magnetic gear is a new type of gear, it utilizes magnetic force to transmit torque. In the transmission of torque by the magnetic gears, the adjacent magnetic gears do not touch each other, and thus no friction and no wear is generated, thereby eliminating the friction loss and mechanical fatigue. Consequently, the magnetic gears is widely used in transmission mechanisms. However, the gear transmission ratio of two magnetic gears is generally fixed. If the transmission ratio needs to be changed, the original magnetic gears should be replaced by another pair of suitable magnetic gears, and thus a plurality of magnetic gears need to be prepared for each one transmission mechanism.
Therefore, there is room for improvement within the art.
The components in the drawings are not necessarily drawn to scale, the emphasis instead placed upon clearly illustrating the principles of the present disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.
Referring to
Referring to
The gear hub 14 includes a fixing portion 141, a connecting portion 143, and a shaft portion 145. The fixing portion 141 is substantially cylindrical, and forms a resisting surface 1412 at a top edge of the fixing portion 141. The resisting surface 1412 is coplanar with the positioning surface 125. The resisting surface 1412 defines a plurality of fixing holes 1414. In the illustrated embodiment, the fixing holes 1414 are evenly arranged in the resisting surface 1412, and positioned in one same circle. The connecting portion 143 is substantially cylindrical, and formed above the resisting surface 1412. The connecting portion 143 defines a plurality of through holes 1432 extending through the connecting portion 143 and the fixing portion 141, and thereby reducing a weight of the gear hub 14. The shaft portion 145 is substantially cylindrical, and extends axially from a center portion of the connecting portion 143. The fixing portion 141, the connecting portion 143, and the shaft portion 145 are aligned in a straight line. The shaft portion 145 defines a pivot hole 1452 extending through the shaft portion 145, the connecting portion 143 and the fixing portion 141.
The connecting plate 16 is annular, and defines a plurality of positioning posts 162. Each positioning post 162 is positioned between two adjacent fixing protrusions 124, and defines a threaded hole 1622. The connecting plate 16 further includes a plurality of receiving portions 164, a plurality of first restricting portions 166, a plurality of second restricting portions 168. Each receiving portion 164 is defined in the connecting plate 16, and around one corresponding positioning post 162. One first restricting portion 166 and one second restricting portion 168 are formed in the receiving portion 164. The first restricting portion 166 forms a first restricting surface 1662 perpendicular to the connecting plate 16, and the second restricting portion 168 forms a second restricting surface 1682 perpendicular to the connecting plate 16. The first restricting surface 1662 is substantially perpendicular to the second restricting portion 168.
A total number of the magnetic members 30 is equal to the total number of receiving portions 164 of the connecting plate 16. In this embodiment, each magnetic member 30 is a bar magnet and has a south pole and a north pole at opposite ends thereof. The magnetic member 30 further defines a connecting hole 32 corresponding to one positioning post 162.
Referring to
Each operating member 70 forms a friction portion 72 at an end, and defines a pivot hole 74 and two connecting holes 76. The friction portion 72 is composed of a plurality of protrusions arranged in a circle. The pivot hole 74 and the connecting holes 76 are aligned in a straight line, and the pivot hole 74 is positioned between the connecting holes 76. Each fixing member 80 is a screw corresponding to the positioning post 162.
Referring to
Referring to
When two magnetic gears 100 are employed, an attraction magnetic force or a repulsion magnetic force can be generated, and thus a torque is transmitted without friction. If the transmission ratio of the magnetic gears 100 needs to be changed, the fixing members 80 are loosened from the operating members 70, and the operating members 70 can be rotated together with the magnetic members 30 and the rotating members 50. A rotation axis of the magnetic member 30 is substantially parallel to a rotation axis of the magnetic gear 100. When the rotating members 50 resist the second restricting surface 1682, the magnetic member 30 is rotated through 90 degrees. As a result, a magnetic torque between the magnetic gears 100 is changed, and thus the transmission ratio of the magnetic gears 100 is changed.
The positioning portion 122 may be omitted in the magnetic gear 100, and the cover 90 can be directly attached to a top edge of the gear flange 12. The receiving portions 164 may be omitted in the connecting plate 16, and the first restricting portions 166 and the second restricting portion 168 protrude from the connecting plate 16. Furthermore, the first restricting portions 166 and the second restricting portion 168 can be omitted, and correspondingly, the rotating members 50 is also omitted.
It is believed that the present embodiments and their advantages will be understood from the foregoing description, and it will be apparent that various changes may be made thereto without departing from the spirit and scope of the disclosure or sacrificing all of its material advantages.
Number | Date | Country | Kind |
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201010264809.7 | Aug 2010 | CN | national |