Toyota Jidosha Kabushiki Kaisha

Toyota Motor Corporation

Toyoda Jidosha Kabushiki Kaisha

Tokyo Diamond Tools Mfg. Co., Ltd.

Libo Zhou

Sumio Kamiya

Hiroshi Eda

Hisao Iwase

Tetsuya Nagaike

Yuji Yoshida

Yoshiaki Tashiro

Noboru Otake

Masaaki Kenmochi

Teruki Yamashita

A synthetic grinding stone used for the polishing of a silicon wafer is composed of a structure containing cerium oxide fine particles as abrasive grains, a resin as a binder, a salt as a filler and a nano diamond as an additive. This synthetic grinding stone is characterized in that the purity of the cerium oxide is not less than 60% by weight, the content of the salt as a filler is not less than 1% but not more than 20%, the volume content of the nano diamond as an additive is not less than 0.1% but less than 20% relative to the total volume of the structure, and the porosity as the volume fraction relative to the total volume of the structure is less than 30%.

Synthetic grinding stone

A precision machining method enabling grinding with high accuracy is provided. The method includes a first step of producing an intermediate ground workpiece by roughly grinding a workpiece (a) with a diamond grinding wheel (b), and a second step of producing a final ground workpiece by grinding the intermediate ground workpiece with a grinding wheel for CMG. In the first step, feed of the rotator () and the base () is controlled in multiple stages with different feed speeds according to control based on the amount of movement, and in the second step, movement of the rotator () and the base () is controlled with a constant pressure or in multiple stages having different constant pressures.

Precision machining method

A precision machining apparatus is structured such that a feed-screw mechanism and an actuator are mounted on a second mount which supports a rotating device that rotates a wheel, and grinding is performed while appropriately adjusting the amount of movement of the second mount in a rough grinding stage through an ultra-precision grinding stage. A posture control device is interposed between a first mount and a rotating device that rotates a grinding target body. The thickness and evenness of the grinding target body are measured by an optical probe and the measurement results are sent to a computer. A feedback command is then sent to the posture control device to reduce the difference between target values and the measurement values and posture control is performed accordingly.

Precision machining apparatus and precision machining method

A precision machining apparatus and a precision machining method capable of carrying out grinding with accuracy by performing switching control, for example, on a device for rotating a grinding wheel according to grinding stages through the amount of movement and constant pressure changed stepwise. To a second pedestalsupporting a rotary devicefor rotating a grinding wheel b, an actuatorand a feed screw mechanismconstituted by at least a feed screwand a nutare attached. In a rough grinding stage, the movement of the rotary deviceand the second pedestalis adjusted through a predetermined amount of movement of the nut. In a super-precision grinding stage, the movement of the rotary deviceand the second pedestalis adjusted by pressure control using stepwise a plurality of pneumatic actuatorsdiffering in pressure performance. An attitude control deviceis interposed between a first pedestaland a rotary devicefor rotating an object a to be ground.

An attitude control device and a precision machining apparatus capable of accurately controlling the attitude of an object mounted on the attitude control device according to grinding stages. The attitude control device is constituted by a first flat-plate memberand a second flat-plate memberdisposed in parallel with the first flat-plate while being spaced apart from the same by a distance L. A spherical memberis interposed between the first and second flat-plate memberswhile fitting its portions in recessesrespectively formed in the first and second flat-plate membersA first actuatorexpandable in a Z-axis direction perpendicular to a plane defined by an X-axis and a Y-axis is interposed between the flat-plate members. Second actuatorsexpandable in a suitable direction in the plane defined by the X-axis and the Y-axis are connected to the second flat-plate memberThe second flat-plate memberis movable relative to the first flat-plate member while being in an attitude with an object mounted thereon. The spherical memberis bonded to the first and second flat-plate membersby an adhesiveelastically deformable.

Growing community of inventors

Hitachi, Japan

Libo Zhou