Dry-ice blast device

1. A dry-ice blast device comprising: an air compressor, an air flow path for guiding an air flow generated by the air compressor to a nozzle, and a dry-ice particle feeder for supplying dry-ice particles into the air flow;

wherein the air compressor is of a low pressure type having a delivery pressure of 1.2-2.5 atm; and

wherein the dry-ice particle feeder supplies the dry-ice particles into the air flow at a position upstream along the air flow path from the nozzle;

wherein the dry-ice particle feeder includes a hopper having a bottom opening and storing the dry-ice particles, and a supplier for causing the dry-ice particles to be discharged through the bottom opening and introduced into the air flow path through a branching pipe portion which transversely branches from the air flow path for allowing gravitational fall of the dry-ice particles and is located out of alignment with the bottom opening;

wherein the supplier includes a movable member having a plurality of accommodation portions for successively coming into communication with the bottom opening of the hopper and the pipe portion, the movable member constantly preventing the bottom opening of the hopper from directly communicating with the branching pipe portion.

2. The dry-ice blast device according to claim 1 , wherein the hopper has an inner surface which is entirely or partially irregular for effecting point contact with the dry-ice particles.

3. The dry-ice blast device according to claim 2 , wherein the irregular surface comprises a resin-coated surface.

4. The dry-ice blast device according to claim 1 , further comprising a knocker for knocking the hopper at a predetermined time interval for giving shock to the dry-ice particles contained in the hopper.

5. The dry-ice blast device according to claim 1 , wherein the supplier further comprises a casing formed with first and second openings communicating with the bottom opening of the hopper and the branching pipe, respectively; the movable member being a rotor rotatably arranged in the casing; wherein the accommodating portions, upon rotation of the rotor are moved to positions for communication with the first opening and the second opening of the casing, respectively, whereby the dry-ice particles are discharged downward from the bottom opening of the hopper into the accommodating portions and are further discharged downward from the accommodating portions into the air transfer path via the branching pipe portion, and

wherein the rotor keeps the first opening and the second opening separated from each other.

6. The dry-ice blast device according to claim 5 , wherein the plurality of accommodating portions are separated from each other by partition walls each having a width smaller than widths of the first and the second openings.

7. The dry-ice blast device according to claim 6 , wherein each of the accommodating portions comprises a through-hole extending in a thickness direction of the rotor, the first and the second openings of the casing penetrating an upper wall and a lower wall of the casing, respectively, the rotor being rotatable between the upper wall and the lower wall of the casing about an axis extending in a thickness direction of the casing, and wherein the rotor has an upper surface and a lower surface each of which is provided with an auxiliary piece disposed at an edge of one of the accommodating portions, the rotor being provided with an elastic member for pressing the auxiliary piece against the upper wall or the lower wall of the casing.

8. The dry-ice blast device according to claim 5 , wherein the rotational speed of the rotor is variable.

9. The dry-ice blast device according to claim 1 , further comprising a check valve for preventing air from flowing reversely toward the air compressor, the check valve being arranged in the air flow path upstream from a position where the dry-ice particles are fed from the dry-ice particle feeder.

10. The dry-ice blast device according to claim 1 , wherein the air flow path includes a flexible hose disposed adjacent to an end of the air flow path, the hose being provided with an operation switch and a wireless transmitter for outputting a wireless signal of data concerning an operational behavior of the operation switch, and wherein the air compressor and the dry-ice particle feeder in operation are controlled based on the wireless signal outputted from the wireless transmitter.

11. The dry-ice blast device according to claim 1 , further comprising a transferable frame provided with wheels for effecting required transfer, wherein the air compressor, a motor for driving the air compressor, the dry-ice particle feeder and piping constituting the air flow path are mounted on the transferable frame.