ELECTROMAGNETIC CONTINUOUSLY VARIABLE TRANSMISSION SYSTEM

An electromagnetic continuously variable transmission system is provided, including: a pulley, including a first disc having an axial sleeve and a second disc, the first disc having a plurality of grooves which extend radially at one side, pulley balls being slidably received within respective ones of the grooves, the first disc having a first slope at another side, the second disc being located by the side of the first disc with the grooves; a driving shaft, disposed in the axial sleeve and the second disc, the first disc being axially slidable relative to the driving shaft; an electromagnetic assembly, disposed on the pulley, including electromagnets spacingly arranged in a part of the grooves; when each of the electromagnets is electrified and generate magnetism, each of the electromagnets magnetically attracts one of the pulley balls toward the axial sleeve.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to an electromagnetic continuously variable transmission system.

Description of the Prior Art

Regarding a continuously variable transmission system used by a common motorcycle, as a revolution speed of an engine increases, the pulley balls in a pulley is driven by a centrifugal force and slide radially within a groove toward outside, the pulley is pushed and moves with a driving shaft toward a belt to push the belt, the belt moves toward an outer edge of a disc to change routing diameters between the belt and the pulley and between the belt and a rear wheel driving disc so as to shift speed in replacement of the transmission effect created by gear ratio. Therefore, in the conventional CVT, the speed shifting time and traits are determined by the weight of the pulley balls. When the pulley balls are heavier, the centrifugal force is greater, and the engine runs in a slow revolution speed and saves oil with less preferable acceleration capability; when the pulley balls are lighter, the centrifugal force is smaller, and the engine runs in a high revolution speed and has better acceleration capability. However, in recent years, most of the vehicles sacrifice their acceleration capability to saves oil, and the consumers using the motorcycles with CVT are unable to strike a balance between acceleration capability and oil-saving effect.

SUMMARY OF THE INVENTION

The major object of the present invention is to provide an electromagnetic continuously variable transmission system, in which a plurality of electromagnets are assembled in a pulley to magnetically attract a part of a plurality of pulley balls to be near one of two ends of a plurality of grooves near an axis so as to accelerate. When the plurality of electromagnets do not magnetically attract the plurality of pulley balls, the plurality of pulley balls can be moved to the other of the two ends of the plurality of grooves remote from the axis to save oil. Therefore, the electromagnetic continuously variable transmission system can provide preferable acceleration capability and oil-saving effect.

To achieve the above and other objects, an electromagnetic continuously variable transmission system is provided, including a pulley, a driving shaft and an electromagnetic assembly. The pulley includes a first disc and a second disc, a center of the first disc has an axial sleeve, one of two sides of the first disc on an axial direction has a plurality of grooves which extend radially, a plurality of pulley balls are respectively slidably received within respective ones of the plurality of grooves, the other of the two sides of the first disc has a first slope, and the second disc is located by the side of the first disc having the plurality of grooves. The driving shaft is disposed within the axial sleeve of the first disc and the second disc, and the first disc is slidable relative to an axial direction of the driving shaft. The electromagnetic assembly is disposed on the pulley and includes a plurality of electromagnets, and the plurality of electromagnets are spacingly arranged in a part of the plurality of grooves and near one end of the axial sleeve. When each of the plurality of electromagnets is electrified and produce magnetism, each of the plurality of electromagnets magnetically attracts one of the plurality of pulley balls corresponding thereto toward the axial sleeve.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Please refer toFIGS. 1 to 8for a preferred embodiment of the present invention. An electromagnet continuously variable transmission system includes a pulley1, a driving shaft4and an electromagnetic assembly5.

The pulley1includes a first disc2and a second disc3, a center of the first disc2has an axial sleeve21, one of two sides of the first disc2on an axial direction has a plurality of grooves22which extend radially, a plurality of pulley balls23are respectively slidably received within respective ones of the plurality of grooves22, the other of the two sides of the first disc2has a first slope24, and the second disc3is located by the side of the first disc2having the plurality of grooves22.

The driving shaft4is disposed within the axial sleeve21of the first disc2and the second disc3, and the first disc2is slidable relative to an axial direction of the driving shaft4. In this embodiment, a third disc7is further provided, the driving shaft4is disposed into the third disc7, the first disc2is between the second disc3and the third disc7, one side of the third disc7toward the first slope24has a second slope71, the first slope24and the second slope71are configured for engagement of a transmission belt8therebetween, through the first disc2moving toward or away from the third disc7, the transmission belt8is pushed or released so that the transmission belt8moves radially outward or inward on the first slope24and the second slope71to shift speed.

The electromagnetic assembly5is disposed on the pulley1and includes a plurality of electromagnets51, and the plurality of electromagnets51are spacingly arranged in a part of the plurality of grooves22and near one end of the axial sleeve21.

Preferably, a number of the plurality of electromagnets51is half a number of the plurality of grooves22. For example, in this embodiment, there are six grooves22and six pulley balls23, and there are three electromagnets51spacingly arranged. In actual practice, when each of the three electromagnets51are electrified and generate magnetism, each of the three electromagnets51magnetically attracts one of the plurality of pulley balls23corresponding thereto toward the axial sleeve21so that the six pulley balls23will not moves radially outward due to a centrifugal force from a revolution of the pulley1. At this moment, a part of the six pulley balls23in the first disc2which are not magnetically attracted by the three electromagnets51are still driven by the centrifugal force to move radially outward to shift speed, and since a part of the six pulley balls23will not move outward due to the centrifugal force during revolution, the pulley1has a lower moment of inertia, and an engine revolves in a higher speed and has a more preferable acceleration capability. On the contrary, if the three electromagnets51are not electrified, the six pulley balls23are not magnetically attracted by the three electromagnets51and can moves outward due to the centrifugal force, the pulley1has a higher moment of inertia, the engine revolves in a lower speed and can save oil. Therefore, a user can decide whether to electrify the electromagnets51to enhance acceleration capability or not to electrify the electromagnets51to save oil in accordance to his/her needs.

Specifically, the electromagnetic assembly5further includes a conducting disc52, the conducting disc52is electrically connected to the three electromagnets51, and the conducting disc52is disposed on one side of the second disc3remote from the first disc2. In this embodiment, a control module6is further provided, the control module6includes a switch61and a power supply unit62, and when the switch61is turned on, the power supply unit62supplies electricity to the conducting disc52to make the three electromagnets51to generate magnetism; on the contrary, when the switch61is turned off, the power supply unit62stop supplying electricity to the conducting disc52to stop the three electromagnets51from generating magnetism.

Preferably, a plurality of conductive brushes53extends radially beyond the conducting disc52so that when the conducting disc52revolve with the second disc3, currents can be effectively transmitted to the conducting disc52.

Furthermore, the three electromagnets51are disposed through the second disc3and project into the six grooves22, in this embodiment, each of the three of electromagnets51has a curved surface511shaped in complementary to a circumference of one of the six pulley balls23so that the six pulley balls can tightly fit to the curved surface511of the three electromagnets51to prevent the six pulley balls23from shaking and enable the pulley1to revolve more stably.

Compared to the embodiment above, in another embodiment shown inFIG. 9, a plurality of conductive brushes53A extends radially beyond the conducting disc52, and the plurality of conductive brushes53A can effectively transmit currents to the conducting disc52. A plurality of electromagnets51A are disposed on an outer circumference of the axial sleeve21, and the plurality of electromagnets51A are flat. Other structures are the same as the embodiment mentioned above.

Given the above, in the electromagnetic continuously variable transmission system, when the plurality of electromagnets are electrified, the plurality of pulley balls are magnetically attracted by the plurality of electromagnets, the pulley will not move outward due to the centrifugal force during revolution, so the pulley has a lower moment of inertia, and the engine revolves in a greater speed and has a more preferable acceleration capability.