Fundamental Studies for the Development of a High Speed Japanese Plow (I)

Relationship between the Moldboard Shape and the Path of Furrow Slice

Abstract

As a basis for the development of a high speed Japanese plow, the author studied the relationships between moldboard shape and path of furrow slices. This relationship could be used for the calculation of a high speed Japanese plow shape which has the same path of furrow slice and the same parformance as the conventional Japanese plow.
The main results are the followings.
1. By means of painting method on the plow surface, the path of furrow slices was obtained from a series of field tests. Then, the obtained path on the plow surace was measured with an optical profilograph.
2. The calculated curve of the minimum path of furrow slice did not agree with the test results. The rectified minimum path in terms of α-plane (X-Z plane) did, however, become closer to the experimental curves.
3. The rectified minimum path is expressed in formulae (8), (9) and (10) in terms of dimensions, and also in the formulae (11), (12) and (13) in terms of angles.
4. The above relationship can be used to obtain the path of furrow slice from the formula of plow shape, and vice versa. In this case, for example, the formula (18) of the path was obtained from a hyperbolic plow surface.