1. Field of the Invention
The present invention relates to a differential unit structure, in particular to one that utilizes engagement and disengagement of first friction plates and second friction plates of a transmission shaft and a driven shaft to form a differential speed.
2. Description of the Prior Art
A conventional electric mobility scooter is provided with an electric power to drive wheels. However, this scooter does not have a differential speed. When the rider makes a turn, he needs to make a wide turn, otherwise the scooter may be overturned.
In view of this and many other shortcomings, the inventor has derived the present invention to solve the problems.
The primary object of the present invention is to provide a differential unit structure comprising a transmission shaft having a connecting tube. The connecting tube comprises a chamber. The inner wall of the chamber is provided with a plurality of troughs for engagement of first friction plates. Each of the first friction plates comprises a shaft aperture and a plurality of blocks around its circumferential edge for meshing with the troughs of the transmission shaft. A driven shaft is connected to the connecting tube of the transmission shaft and comprises a connecting rod provided with blocks thereon. Second friction plates are provided on the connecting rod of the driven shaft and engage with the first friction plates. Each of the second friction plates comprises a shaft aperture with a plurality of troughs around an inner edge for meshing with the blocks of the driven shaft. An engaging seat is provided on the driven shaft and urged by an elastic member to urge the first friction plates and the second friction plates. An activating rod penetrates through the connecting tube of the transmission shaft and comprises a push block to move the engaging seat.
It is another object of the present invention to provide a differential unit structure, which is safe for a rider.
It is a further object of the present invention to provide a differential unit structure, which is easy to operate.
As shown in
The transmission shaft 1 is connected to a power supply, and comprises a fixed end 11 and a connecting tube 12 at the other end. The connecting tube 12 comprises a chamber 13 with a plurality of troughs 14 on the inner wall of the chamber 13, as shown in
The second friction plates 2 are deposited in the chamber 13 of the transmission shaft 1. Each second friction plate comprises a shaft aperture 21 and a plurality of blocks 22 around its circumferential edge to mesh with the troughs 14 of the transmission shaft 1.
The driven shaft 3 is connected to the connecting tube 11 of the transmission shaft 1 and is activated by the transmission shaft 1. One end of the driven shaft 3 is a fixed end 31 and the other end is provided with a connecting rod 32 inserting through the shaft aperture 21 of the first friction plate 2. The connecting rod 32 is provided with a plurality of blocks 33 thereon, as shown in
The second friction plates 4 are provided on the connecting rod 32 of the driven shaft 3. The first friction plates and the second friction plates are alternatively arranged and abutted to one another. Each second friction plate 4 has a shaft aperture 41. The inner wall of the shaft aperture 41 is provided with a plurality of troughs 42 for engagement of the blocks 33 of the driven shaft 3.
The engaging seat 5 is deposited on the driven shaft 3, and comprises an elastic member 51 to urge the first friction plates 2 and the second friction plates 4 together. The engaging seat 5 further comprises a flange 52 extending from one end thereof.
As shown in
To operate the present invention, as shown in
To make a left turn of the electric mobility scooter incorporated with the present invention, the handle A is turned to the left, as shown in