Matsushita Electric Industrial Co., Ltd.

Michinori Nagahiro

Susumu Maruno

Masaharu Ushihara

Seiko Minamide

Yoshinobu Nakata

Masami Nakagawa

Noboru Miyaji

Shinobu Nakata

Humio Yamazaki

Hiroo Hosono

A gradation thermal printhead having a plurality of heat generating elements each having a heat generating body connected between a pair of electrodes, the electric resistance value of the heat generating body being locally increased in one or more portions thereof. Disclosed also is a gradation heat transfer printing apparatus making use of the gradation thermal printhead mentioned above and employing an energy controlling means for varying the voltage or pulse width of the signal pulse voltage applied to the thermal printhead, thereby allowing a control of the area of the printed dot corresponding to one heat generating element, i.e., the density of printing, thus attaining a gradation control of the printed image.

Gradation thermal printhead and gradation heat transfer printing

A plurality of magnetic styli are arranged in a row for effecting a line recording. A magnetic styli are magnetized by a magnet held in contact with these styli so that a magnetic fluid attaching to the styli is protruded from each stylus to form continuous wave-like protrusions along the row of the styli. The magnetic fluid protruded from the styli is to fly or migrate as a high voltage is applied selectively between the styli and a control electrode which opposes to the styli across the recording paper, due to a Coulomb force acting on the ends of the protrusions. In consequence, a recording is made by the magnetic fluid serving as an ink on the recording paper in accordance with a recording signal. A predetermined head or height differential is preserved between the magnet and an ink tank. The magnet and the ink tank are connected to each other by means of a pipe filled with the magnetic fluid. A slight gap is formed in the connection between the pipe and the magnet. This gap, however, is completely covered and closed by the magnetic fluid attaching to the magnet so that the ambient air is prevented from coming into the pipe. A vacuum is generated in the pipe due to the aforementioned height differential to control the amount of the magnetic fluid supplied to the magnet. As the magnetic fluid is consumed progressively at the ends of the protrusions, the magnetic fluid is supplied to the protrusions from the ink tank through the pipe and the gap. In consequence, various troubles such as printing failure due to magnetic thickening of the magnetic fluid which inevitably takes place in the conventional apparatus incorporating an elongated magnet type ink supplying device, is completely eliminated to ensure a stable printing of a high quality.

Magnetic fluid recording apparatus

An automatic tape winding device in which the leading end portion of a tape-like article inserted into the device is pressed against a portion of a reel hub rotating at a peripheral speed higher than the speed of said tape-like article and, upon passage of the point of pressure contact of said tape-like article with said reel hub, is again led to said point of pressure contact, and such operation is repeated, whereby said leading end portion of the tape-like article is automatically engaged with said reel hub.

Automatic tape winding device

Growing community of inventors

Katano, Japan

Michinori Nagahiro