PURPOSE: To scarcely adhere carbon of a copy to a bottom layer and to be easily removed even in the case of adhering by forming it of a polyvinyl chloride to be laminated at a high temperature, and forming a three-layer structure having different hardnesses, thereby providing a high production efficiency, possibility of transporting and stocking with a rolled state as a product CONSTITUTION: The mat 10 used for the other has a three-layer structure of a front surface layer 11, an intermediate layer 12 and a bottom layer 13 The layers 11, 12, 13 are formed of polyvinyl chloride resins having different hardnesses from each other and laminated at a high temperature The layer 11 has the lowest hardness The layer 13 has a highest hardness The layer 12 has an intermediate hardness between the layers 11 and 13 The layers have flexibility of rolling in a rolled state Accordingly, a damage mark generated on the layer 11 is blocked and original smoothness can be easily recovered The layer 13 improves durability of the entire mat 10 The layer 12 can laminate for a roller type for a mass production in a short time

Combination cutting mat and desk mat and manufacture thereof

PURPOSE:To obtain a vibration suppressing effect with a high degree of accuracy, by calculating a variation rate of rotational speed of a main engine, and by adding thus calculated value to a speed detection signal from the main engine to control the speed of a motor in accordance with the deviation value between thus added speed detection signal from the engine and a speed signal from the motor. CONSTITUTION:Even though the rotational speed of a main engine 10 is slightly changed, the variation rate is added to a speed detection signal from the main engine 10, and therefore, the value of the signal is such that the rotation speed of the main engine 10 is as if changed greatly. As a result, the deviation between the speed detection signal from the main engine 10 and a speed signal from a motor 5 becomes larger, and therefore, the followability of the motor 5 may be enhanced with respect to even a small change in the rotation of the main engine 10. Accordingly, it is possible to obtain a vibration suppressing effect with a high degree of accuracy.

Yamada Manabu

Papers

Control device for dynamic vibration absorber