What is claimed is:
1. A metal-less bond grinding stone for dressing a ground surface by electrolytic dressing, comprising:
abrasive grains and a bond portion for holding the abrasive grains, wherein the bond portion comprises a carbon-containing nonmetallic material alone.
2. The metal-less bond grinding stone according to claim 1, which comprises a mixture of abrasive grains, carbon powder and resin powder and which is formed by sintering the mixture under pressure at a softening temperature lower than a resin melting temperature.
3. The metal-less bond grinding stone according to claim 2, wherein a blend ratio of carbon to the resin is about 20% or more and about 30% or less.
4. The metal-less bond grinding stone according to claim 1, which comprises a mixture of the abrasive grains and carbon-containing powder and which is obtained by sintering the mixture to impart conductivity and mechanical strength to the carbon-containing powder.
5. The metal-less bond grinding stone according to claim 1, which comprises a mixture of the abrasive grains and resin powder and which is obtained by sintering the mixture to carbonize at least a part of the resin powder.
6. An electrolytic in-process dressing grinding method comprising a step of applying a voltage between a metal-less bond grinding stone (1) having a bond portion comprising a carbon-containing nonmetallic material alone and an electrode (2) while a conductive grinding fluid (3) is allowed to flow between the metal-less bond grinding stone (1) and the electrode (2), and a step of grinding a work piece (4) while the grinding stone is subjected to electrolytic dressing, wherein a current which is allowed to flow between the grinding stone and the electrode is controlled within a desired range.
7. An electrolytic dressing grinding apparatus using a metal-less bond grinding stone, which comprises a metal-less bond grinding stone (1) having a bond portion comprising a carbon-containing nonmetallic material alone, a carbon electrode (2) which is located at a distance from a grinding surface of the metal-less bond grinding stone (1) and at least whose side opposite to the grinding stone is made from a carbon material, a grinding fluid supply means (6) for causing a conductive grinding fluid (3) not containing any heavy metal ions to flow between the grinding stone and the electrode, and an power source unit (8) for electrolytic dressing which applies a voltage between the grinding stone and the electrode and which controls the current flowing between them within a predetermined range.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A planting device comprising:
one or multiple planting containers, each having a water storage portion capable of storing an amount of planting water therein and a planting space capable of mounting a water-absorbent planting bed material, the container being capable of forming, at least on a side of its front face, an opening portion exposing the planting bed material therethrough; and
a frame member capable of surrounding and supporting the one or multiple planting containers, with the one or multiple planting containers being detachably attachable thereto;
wherein the planting container forms a projection in a portion of an outer circumference thereof and the frame member includes, in an outer circumference thereof, an interlocking opening portion to be engaged with the projection.
2. The planting device according to claim 1, wherein an overflow pipe for discharging an amount of the planting water over a predetermined level is formed integral with the planting container.
3. The planting device according to claim 2, wherein the projection comprises a lower end of the overflow pipe.
4. The planting device according to claim 2, wherein the overflow pipe is formed with an inclination relative to the perpendicular line as viewed in its front view.
5. The planting device according to claim 1, wherein a transparent water-level checking portion is formed in at least one lateral face of the planting container to project therefrom, and the water-level checking portion constitutes the projection.
6. The planting device according to claim 1, wherein the planting container is formed integral by blow-molding of resin.
7. The planting device according to claim 1, wherein the opening portion is disposed with an upward offset from the vertical center; and downwardly of the opening, there are formed a pair of supporting portions for supporting the planting bed material along a frontrear direction, with the supporting portions projecting inwards.
8. The planting device according to claim 1, wherein in opposed lateral faces of the planting container, there are integrally formed gripping portions projecting toward the planting space, the gripping portions acting also as restricting means for restricting lateral displacement of the planting bed material.
9. The planting device according to claim 1, wherein the planting container has a rear face side opposed to the front face side, and on the rear face side, an auxiliary opening portion can be formed in opposition to the opening portion.