CORE SAND REGENERATION SYSTEM

Abstract

A rotary kiln-type core sand regeneration system, having a rotating cylinder, a burner for directing a flame into the rotating cylinder, a motor for rotating the rotating cylinder, front and rear boundary frames and rollers for supporting the rotating cylinder, and a platform on which the rotating cylinder, the burner, the motor, the front and rear boundary frames and the rollers are mounted. The rotating cylinder has a used core sand inlet, an exhaust cylinder and a preliminary heating cylinder arranged from the rear and a regenerated core sand outlet formed at a front part thereof, the rotating cylinder being directly coupled to the burner at a front end, and including at least one combustion cylinder having passing holes through which the core sand and the flame from the burner are passed in a front part thereof.

Claims

1-13. (canceled)

14. A rotary kiln-type core sand regeneration system, comprising a rotating cylinder, a burner for directing a flame into the rotating cylinder, a motor for rotating the rotating cylinder, front and rear boundary frames and rollers for supporting the rotating cylinder, and a platform on which the rotating cylinder, the burner, the motor, the front and rear boundary frames and the rollers are mounted, the rotating cylinder having a used core sand inlet, an exhaust cylinder and a preliminary heating cylinder arranged from the rear and a regenerated core sand outlet formed at a front part thereof, the rotating cylinder being directly coupled to the burner at a front end, the rotating cylinder having core sand scooping plates, attached to an interior surface thereof and slightly inclined downward and forward with respect to a horizontal plane, for scooping, lifting up and dropping, and dispersing core sand at the bottom of the rotating cylinder and transmitting it forward, and including at least one combustion cylinder having passing holes through which the core sand and the flame from the burner are passed in a front part thereof, wherein used core sand is introduced through the used core sand inlet into the rotating cylinder, transmitted forward through the preliminary heating cylinder in the rotating cylinder while being repeatedly scooped, lifted up and dropped, and dispersed by the core sand scooping plates, and transmitted to the regenerated core sand outlet after the binder adhering to the surface of the used core sand is combusted or fused in the combustion cylinder.

15. The rotary kiln-type core sand regeneration system according to claim 14, wherein core sand retaining plates for temporarily retaining the core sand are attached to the interior surface of the rotating cylinder.

16. The rotary kiln-type core sand regeneration system according to claim 14, wherein the at least one combustion cylinder having passing holes includes two or more combustion cylinders concentrically arranged in a multilayered fashion.

17. The rotary kiln-type core sand regeneration system according to claim 14, wherein the rotating cylinder has an adjustable rotational speed.

18. The rotary kiln-type core sand regeneration system according to claim 14, wherein the rotating cylinder has an adjustable inclination angle.

19. The rotary kiln-type core sand regeneration system according to claim 14, wherein a heat insulating material is provided on a wall surface of the rotating cylinder.

20. A batch-type core sand regeneration system, comprising a batch cylinder, a burner for directing a flame into the batch cylinder, a motor for rotating at least one combustion cylinder and a rotating cylinder provided in the batch cylinder, and a platform on which the batch cylinder, the burner and the motor are mounted, the batch cylinder having an exhaust cylinder, the batch cylinder having a first end face directly coupled to the burner and a second end face through which a rotating shaft operatively connected to the motor extends, the combustion cylinder and the rotating cylinder being concentrically attached to the rotating shaft in the batch cylinder, the rotating cylinder having core sand scooping plates attached to an interior surface thereof, wherein a series of operations including causing the core sand scooping plates attached to the rotating cylinder to scoop, lift up and drop, and disperse core sand introduced through a used core sand inlet formed through the batch cylinder and accumulated at the bottom of the batch cylinder by rotating the rotating shaft, and combusting and fusing the binder adhering to the surface of the used core sand in the combustion cylinder having passing holes, which is also being rotated by the rotation of the rotating shaft, is repeated for a predetermined period of time to regenerate the core sand, and the regenerated core sand is taken out of a regenerated core sand outlet formed through the batch cylinder.

21. The batch-type core sand regeneration system according to claim 20, wherein the center of the rotating cylinder is located on a vertical line passing through the center of the batch cylinder and a predetermined distance below the center of the batch cylinder so that the core sand scooping plates attached to the rotating cylinder cannot contact the bottom of the batch cylinder and the core sand can be efficiently scooped.

22. The batch-type core sand regeneration system according to claim 20, wherein the at least one combustion cylinder having passing holes in the batch cylinder includes two or more combustion cylinders concentrically attached to the rotating cylinder in a multilayered fashion.

23. The batch-type core sand regeneration system according to claim 20, wherein the combustion cylinder and the rotating cylinder in the batch cylinder has an adjustable rotational speed.

24. The batch-type core sand regeneration system according to claim 20, wherein the batch cylinder have an adjustable inside temperature.

25. The batch-type core sand regeneration system according to claim 20, wherein the batch cylinder is equipped with a blast door.

26. The batch-type core sand regeneration system according to claim 20, wherein a heat insulating material is provided on a wall surface of the batch cylinder.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0054] FIG. 1 is a front schematic view of a rotary kiln-type core sand regeneration system.

[0055] FIG. 2 is a right side schematic view of the rotary kiln-type core sand regeneration system.

[0056] FIG. 3 is a schematic layout view of a cross-section of the rotary kiln-type core sand regeneration system having a rotating cylinder provided with core sand retaining plates.

[0057] FIG. 4 is a schematic layout view, seen from the front, of the rotary kiln-type core sand regeneration system having a rotating cylinder provided with core sand retaining plates.

[0058] FIG. 5 is a schematic view of various combustion cylinders for the rotary kiln-type core sand regeneration system and their passing holes.

[0059] FIG. 6 is a schematic view of a burner and a combustion cylinder of the rotary kiln-type core sand regeneration system.

[0060] FIG. 7 is a photograph of a prototype of the rotary kiln-type core sand regeneration system.

[0061] FIG. 8 is a photograph of a motor and a roller for rotating a rotating cylinder of the rotary kiln-type core sand regeneration system.

[0062] FIG. 9 is a photograph of a front boundary frame and a burner of the rotary kiln-type core sand regeneration system.

[0063] FIG. 10 is a photograph of the front boundary frame of the rotary kiln-type core sand regeneration system taken with the burner removed.

[0064] FIG. 11 is a photograph of the inside of the rotating cylinder of the rotary kiln-type core sand regeneration system as seen from the front boundary frame.

[0065] FIG. 12 shows photographs of the inside of the rotating cylinder as seen from the front boundary frame as in the case of FIG. 11.

[0066] FIG. 13 shows photographs of used core sand and regenerated core sand that has been passed through the rotary kiln-type core sand regeneration system.

[0067] FIG. 14 is a schematic layout view of a batch-type core sand regeneration system.

[0068] FIG. 15 is a front schematic view of the inside of a batch cylinder.

[0069] FIG. 16 is a cross-sectional schematic view of the inside of the batch cylinder.

[0070] FIG. 17 is a basic plan view of the batch-type core sand regeneration system.

[0071] FIG. 18 is a basic front view of the batch-type core sand regeneration system.

[0072] FIG. 19 is a basic left side view of the batch-type core sand regeneration system.

[0073] FIG. 20 is a front photograph of the batch-type core sand regeneration system in the course of trial production.

[0074] FIG. 21 is a left side photograph of the batch-type core sand regeneration system in the course of trial production.

DETAILED DESCRIPTION OF THE INVENTION

[0075] Examples of this application are shown below.

Example 1

[0076] FIG. 1 through FIG. 13 are drawings and photographs of a rotary kiln-type core sand regeneration system 1. A prototype of the rotary kiln-type core sand regeneration system 1 is shown in FIG. 7. FIG. 7 is a view seen from the back side in contrast to the front schematic view of FIG. 1, and its front and rear are therefore inverted. Used core sand prepared in a hopper 71 is introduced into a rotating cylinder 3 in a rear boundary frame 2 through a used core sand inlet 21. The used core sand is passed through passing holes 34 of a combustion cylinder 32 or over the surface of the combustion cylinder 32 in the rotating cylinder 3 from the left side of FIG. 7 to the right side, where a burner 4 is located, while being repeatedly scooped, lifted up and dropped, and dispersed by core sand scooping plates 33 in the rotating cylinder 3, and the binder adhering to the surface of the used core sand is removed by combustion or fusion. The used core sand is then transported from inside of a front boundary frame 6 to a regenerated core sand outlet 61. A control panel 8 controls the start and stop of the core sand regeneration system, the rotational speed of the rotating cylinder 3, and so on. The system is mounted on a platform 7. Although not shown, a multiple dust removal device is located on the extension of an exhaust cylinder 22 to give consideration to the environment.

[0077] FIG. 8 shows photographs of a motor 5 and a roller 51 for rotating the rotating cylinder. Because the motor 5 is located on the left side toward the front on the platform, it is visible in FIG. 1 but not in FIG. 7. The torque of the motor 5 is transmitted to the rollers 51 to rotate the rotating cylinder 3. It should be noted that because a trademark was affixed to a part of the motor 5, that part was erased.

Example 2

[0078] FIG. 9 is a layout photograph of the front boundary frame 6 and the burner 4. The regenerated core sand outlet 61 is located below the front boundary frame 6.

[0079] FIG. 10 is a photograph of the front boundary frame 6 taken with the burner 4 removed, and FIG. 11 is a photograph of the inside of the rotating cylinder 3 seen from the front boundary frame 6. The combustion cylinder 32 having the passing holes 34 is provided within the rotating cylinder 3. Further, FIG. 12 shows the layout of the core sand scooping plates 33 and core sand retaining plates 36 in the rotating cylinder 3. FIGS. 12A and 12B are photographs taken from different positions. A C-shaped steel is used as each core sand scooping plate 33, and a plurality of core sand scooping plates 33 extend from the rear to the front of the rotating cylinder 3. The core sand retaining plates 36 are perpendicularly fixed to the interior wall of the rotating cylinder 3, and a U-shaped member is used for each core sand retaining plate 36.

Example 3

[0080] FIGS. 13A and 13B show used core sand and regenerated core sand having been passed through the rotary kiln-type core sand regeneration system 1, respectively. Although their difference is not apparent from FIG. 13, it can be easily felt with fingers because the former is sticky whereas the latter is smooth.

Example 4

[0081] FIG. 14 through FIG. 19 are schematic views of a batch-type core sand regeneration system 10. FIG. 17 is a plan view, FIG. 18 is a front view, and FIG. 19 is a left side view. In FIG. 17, a blast door 124 is provided at an upper part of a batch cylinder 12. This is to prepare for accidental explosion of an organic solvent or the like to ensure safety because a binder containing the organic solvent and so on adheres to the surface of the used core sand and because the batch cylinder 12 is coupled to an exhaust cylinder 121 and is in an airtight state. A used core sand inlet 122 shown in FIG. 18 is opened and closed by an air cylinder 128 via a control panel 17. A regenerated core sand outlet 123 is also opened and closed by another air cylinder 128 via the control panel 17 as shown in FIG. 19. The rotation of a motor 16 rotates a sprocket 164 via driving belt 162, which rotates a rotating shaft 161 operatively connected thereto to rotate a combustion cylinder 13 and a rotating cylinder 14, thereby rotating the core sand scooping plates 141 attached to the rotating cylinder 14.

Example 5

[0082] FIG. 20 and FIG. 21 are photographs of a batch-type core sand regeneration system 10 in the course of trial production, and the exhaust cylinder 121, the control panel 17 and so on have yet to be attached. Compared to the rotary kiln-type core sand regeneration system 1 of the prior application (JP Patent Application 2015-231682), the batch-type core sand regeneration system 10 has an advantage of being small in size and occupying less space. In FIG. 20, an inspection opening 181 is provided outside the batch cylinder 12. In addition, as shown in FIG. 21, a chain is used as the driving belt 162. Because the inside of the batch cylinder 12 reaches 700° C. to 800° C., a heat-resistant stainless steel is used for the interior wall of the batch cylinder 12, the rotating cylinder 14, and the combustion cylinder 13.

[0083] The used core sand is crushed by a crusher (not shown), and collected into a primary tank (not shown). The used core sand is then weighed, and a predetermined amount of used core sand is stored in a pool tank (not shown). In the rotary kiln-type core sand regeneration system 1, the used core sand stored in the pool tank is continuously introduced into the used core sand inlet 21 and continuously regenerated. When the burner 4 is ignited and the combustion cylinder 32 and the rotating cylinder 3 are started to rotate, the core sand scooping plates 33 are rotated and a series of operations including scooping, lifting up and dropping, and dispersing the used core sand, and, at the same time, removing the binder adhering to the surface of the used core sand by combustion or fusion in the combustion cylinder 32 with passing holes 34, which is also being rotated, is repeated for a predetermined period of time. The resulting regenerated core sand is transported to the regenerated core sand outlet 61 and falls into a storage tank (not shown). In the batch-type core sand regeneration system 10, the used core sand inlet 122 is opened and a predetermined amount of used core sand is introduced into the batch cylinder 12. When the used core sand inlet 12 is closed, the burner 15 is ignited and the combustion cylinder 13 and the rotating cylinder 14 are started to rotate to rotate the core sand scooping plate 141. Then, a series of operations including scooping, lifting up and dropping, and dispersing the used core sand, and, at the same time, removing the binder adhering to the surface of the used core sand by combustion or fusion in the combustion cylinder 13 with passing holes 131, which is also being rotated, is repeated for a predetermined period of time. After maintaining the temperature inside the batch cylinder 12 at 700° C. or higher for 30 minutes, the rotation of the rotating shaft 161 is stopped, the regenerated core sand outlet 123 is opened and the regenerated core sand falls into a storage tank (not shown). The core sand regenerated in the rotary kiln-type core sand regeneration system 1 or the batch-type core sand regeneration system 10 is high in temperature and is therefore cooled by spraying water. This series of operations is performed automatically. The regenerated core sand is put into flexible container bags and delivered to core manufactures and so on. It should be noted that maintaining the temperature at 700° C. for 30 minutes is shown as examples of regenerate conditions, and the temperature and time conditions vary depending on the type of the binder.

INDUSTRIAL APPLICABILITY

[0084] A core is an indispensable technique for the production of precision components of transportation machines and so on, and the quality of core has a significant effect on the fuel efficiency. In addition to having proper particle size and composition, the individual particles of the core sand need to be round. Each core is expendable without exception, and used core sand needs regeneration. The core sand regeneration system of this application has the advantage of being able to regenerate used core sand using an inorganic binder. The rotary kiln-type core sand regeneration system can continuously regenerate used core sand, and the batch-type core sand regeneration system can regenerate core sand with different binders on a batch-by-batch basis. Because both are not complicated in structure in contrast to conventional used core sand regeneration systems, they can be offered at a low price and expected to be in high demand.

DESCRIPTION OF REFERENCE NUMERALS

[0085] 1: rotary kiln-type core sand regeneration system [0086] 2: rear boundary frame, 21: used core sand inlet, 22: exhaust cylinder [0087] 3: rotating cylinder, 31: preliminary heating cylinder, 32: combustion cylinder, 33: core sand scooping plate [0088] 34: passing hole, 35: heat insulating material, 36: core sand retaining plate [0089] 4: burner [0090] 5: motor, 51: roller [0091] 6: front boundary frame, 61: regenerated core sand outlet [0092] 7: platform, 71: hopper, 72: (platform leg) height adjusting jig [0093] 8: control panel [0094] 10: batch-type core sand regeneration system [0095] 12: batch cylinder, 121: exhaust cylinder, 122: used core sand inlet [0096] 123: regenerated core sand outlet, 124: blast door [0097] 125: center of batch cylinder, 126: vertical line, 127: heat insulating material [0098] 128: air cylinder [0099] 13: combustion cylinder, 131: passing hole, 132: center of combustion cylinder [0100] 14: rotating cylinder, 141: core sand scooping plate, 142: center of rotating cylinder [0101] 15: burner, 151: combustion cover [0102] 16: motor, 161: rotating shaft, 162: driving belt [0103] 163: rotational bearing, 164: sprocket [0104] 17: control panel, 171: thermocouple, 172: communication line [0105] 18: platform frame, 181: inspection opening

[0106] It should be noted that the components and parts of the rotary kiln-type core sand regeneration system and the batch-type core sand regeneration system are named the same but designated by different numerals. This is for easy description of their differences and because this application is made by combining two patent applications filed in Japan into one patent application to claim for priority based thereon. When components or parts are named the same in both applications, they may be different in shape but are the same in function and use.