APPARATUS FOR CRUSHING THINGS

Abstract: An apparatus for crushing waste, having two rotating drums (15 and 16) mounted substantially at the same level and in parallel with each other in a casing (11) having an inlet (12) and an outlet (14). The rotating drums (15 and 16) are driven by a motor (17) and the rotations thereof are synchronized with each other by gears (22 and 23) mounted on the rotating drums (15 and 16), respectively. A plurality of cutting disks (25) are obliquely fixed to the outer circumferential surface of each of the rotating drums (15 and 16) so that each one of the cutting disks (25) of one rotating drum (15) may be substantially parallel with each one of the cutting disks (25) of the other rotating drum (16) when the rotating members (15 and 16) have certain phase angles.

Description: The present invention relates to a crusher which crushes things such as waste, wood, plastic and the like, and more particularly, to a crusher which crushes such things utilizing cutting disks. JP-A-58-500890 discloses a crusher of this kind. Referring to Figs. 1 and 2, this crusher is provided with a casing 3 fixed to a base 4 and having an inlet 1 and an outlet 2, screws 5a, 5b, and 5c rotatably mounted in the casing 3 in parallel with each other, and a motor 6 connected to the screws 5a, 5b and 5c for driving the screws 5a, 5b, and 5c. A spiral cutting blade 8a is dextrously mounted at regular pitches on a circumferential surface of a shaft 7a of the first screw 5a. A spiral cutting blade 8b is mounted dextrally at the same pitch as the above-described pitch on a circumferential face of a shaft 7b of the second screw 5b. A spiral cutting blade 8c is mounted sinistrally at the same pitch as the above-described pitch on a circumferential face of a shaft 7c of the third screw 5c. As shown in Fig. 2, waste introduced from the inlet 1 of the casing 3 into the space between the screws 5a and 5b and between the screws 5b and 5c is compressed, cut, shredded by the cutting blades 8a, 8b, and 8c. At this time, the cutting blade 8a rotates counterclockwise and the cutting blades 8b and 8c rotate clockwise. Thereafter, the crushed pieces are discharged from the outlet 2. However, the crusher has a disadvantage that the waste is not crushed more than once by the cutting blades 8a, 8b, and 8c while the screws 5a, 5b, and 5c rotate for 360°. The crusher has another disadvantage that if the waste includes a stiff foreign matter, the foreign matter is sandwiched between the adjacent screws 5a and 5b and/or between the adjacent screws 5b and 5c. As a result, the shafts 7a, 7b, and/or 7c may be stopped and this may stop the crushing operation. In addition, part of the screws 5a, 5b, and/or 5c may be broken, which necessitates the replacement of the screw(s). Another related art is disclosed in Japanese Utility Model Laid-open Publication No. 48-63389. A crusher assembly disclosed therein is provided with a first crusher consisting of crushing rollers or a compressing roller which crushes waste into large pieces. The crusher assembly is also provided with a second crusher consisting of a rotating drum and a fixed blade which crushes the large crushed pieces into small pieces. The first crusher is mounted on an upper portion of the crusher assembly and the second one is mounted on a lower portion thereof. This causes the crusher assembly to be large, so that a large space is required for installing it and further, the crusher may fail easily because it employs many parts. DE-A-1062977 discloses an apparatus for crushing things, which includes a plurality of cutting disks fixed on a rotating member, the cutting disks being fixed on the rotating member with a predetermined inclination with respect to the axis of the rotating member. EP-A-0130618 discloses another apparatus for crushing things, which includes a cutting disc fixed on a rotating member with a predetermined inclination with respect to the axis of the rotating member. According to the present invention, there is provided an apparatus for crushing things comprising: a casing having an inlet and an outlet; at least one first rotating member and a second rotating member rotatably mounted in the casing, axes of rotation thereof being in parallel with each other; means for rotating the first and second rotating members; and a screw fixed to an outer circumferential surface of the second rotating member; wherein: a plurality of cutting disks are obliquely fixed to an outer circumferential surface of at least one first rotating member at predetermined regular intervals so as to have a predetermined inclination with respect to the axis of the first rotating member; a plurality of blades are spirally fixed to the outer circumferential surface of the second rotating member so that the blades intersect the screw; and a stationary blade is fixed to an inner surface of the casing so as to confront the second rotating member; whereby crushing operation is performed by the cutting disks and the screw, followed by further crushing operation by the blades on the second rotating member and the stationary blade. The operation of the apparatus is described hereinbelow. When one first rotating member and one second rotating member are used, the first one for the cutting disks and the second one for the screw, waste thrown into between the rotating members is compressed and crushed into large pieces by the cutting disks and the screw. Thereafter, the large pieces of the waste are compressed and crushed into small pieces by the blades fixed to the second rotating member and the stationary blade. Embodiments of the present invention will now be described in detail, by way of example, with reference to the accompanying drawings, in which: Figs. 1 and 2 are vertical sectional and plan views showing a conventional crusher; Fig. 3 is a front view of a crusher of a fifth embodiment of the present invention; Fig. 4 is a view taken along the line A-A shown in Fig. 3; Fig. 5 is a cross-sectional view taken along the line B-B shown in Fig. 3; Fig. 6 is a view taken along the line C-C shown in Fig. 5; Fig. 7 is a view taken along the line D-D shown in Fig. 5; and Fig. 8 is a view taken along the line E-E shown in Fig. 5. An embodiment of the present invention is described with reference to Figs. 3 through 8. Referring now to Figs. 3, 4, there is shown a casing 301 which has an inlet 302 at an upper portion thereof and an outlet 303 at a lower portion thereof. Two rotating drums 304 and 314 serving as rotating members are provided in the casing 301 in such a manner that the rotating drums are arranged in parallel with each other and at the same level, and a further rotating drum 305 is provided below the rotating drums 304 and 314. The rotating drums 304, 314, and 305 are supported by respective bearings 306, and ends of the rotating drums 304 and 314 are coupled with motors 307 and 317, whereby the rotating drum 304 is rotated counterclockwise and the rotating drum 314 clockwise. The rotation of the rotating drum 314 is transmitted to the rotating drum 305 through a transmission member 308. As shown in Fig. 25, the upper rotating drums 304 and 314 are respectively provided with a plurality of cutting disks 309 and 319 arranged at predetermined intervals. The cutting disks 309 and 319 are oblique with respect to the rotating drums 304 and 314, respectively. The cutting disks 309 and 319 apply force acting in opposite directions, i.e., shearing force, to waste through the rotations in the opposite directions of the rotating drums 304 and 314. The waste is compressed and crushed in the space between the cutting disks 309 and 319 by such shearing force. Referring to Figs. 7 and 8, a screw 310 is mounted on the outer circumferential surface of the lower rotating drum 305 and a plurality of blades 311 are also spirally fixed thereto in such a manner that the blades 311 intersect the screw 310. The blades 311 helically run in a direction opposite to the direction in which the screw 310 turns. The helix angle of the blade 311 is much larger than that of the screw 310. Waste is compressed and crushed into large pieces by the screw 310 in cooperation with the cutting disks 319 mounted on the rotating drum 314. A stationary blade 312 is fixed to the casing 301 so as to confront the rotating drum 305. This stationary blade compresses and crushes the waste once roughly crushed into small pieces in cooperation with the blades on the rotating drum 305. Since the helical angle of each of the blades 311 is large, that is, the angle between a blade 311 and the stationary blade 312 is small, the waste is easily and smoothly crushed. A baffle plate 313 prevents non-crushed waste from dropping below it. Brackets 315 support the bearings 306 and the motors 307 and 317. In this embodiment, the blades 311 helically run in a direction opposite to the direction in which the screw 310 turns, but the former may run in the same direction as that of the screw 310 under the condition of a large helix angle. In this case, similar efficiency can be also obtained. The operation of this embodiment is described hereinbelow. Waste thrown into the casing 301 from the inlet 302 is introduced between the rotating drums 204 and 214, compressed and roughly crushed by the cutting disks 309 and 319 mounted on the respective rotating drum 304 and 314 rotating in the opposite directions shown by the arrows in Fig. 5. The waste crushed into comparatively large fragments passes through the space between the upper and lower rotating drums 314 and 305 because the rotating drum 305 is rotating in the direction shown by the arrow in Fig. 5. At this time, the waste is further crushed by the cutting disks 319 and the screw 310 and also by the cutting disks 319 and the blades 310 which gently incline with respect to the axis of the rotating drum 305. When the roughly crushed waste is introduced toward the stationary blade 312 owing to the directions of rotation of the upper and lower rotating drums 314 and 305, the waste is further crushed into small fragments by the stationary blade 312 and the blades 311. Even though any waste fragment slides down the blade 311, the screw 310 stops the slide. Therefore, the fragment can be reliably crushed into fine pieces. Three rotating drums are used to perform a crushing operation in this embodiment. However, the advantage of this embodiment can be obtained even when only one upper rotating drum 304 or 314 is used. As described above, a plurality of cutting disks are mounted on at least one rotating drum with certain inclination with respect to the axis thereof, while blades 311 and a screw are mounted on the other rotating drum. A crushing operation is carried out by the cutting disks and the screw and the blades first. Then, further crushing operation is effected by the blades and a stationary blade which is fixed to a casing so as to confront the other rotating drum. The crushing operation consists of two stages, one for crushing waste into large pieces and the other for crushing the large pieces into smaller pieces. In both stages of the crushing operation the other rotating drum functions, so that a crusher of the present embodiment can be compact. Further, because the number of components of the crusher can be reduced owing to the multifunction of one of the rotating drums, troubles or failures do not occur so often and in addition, such a crusher can be manufactured at a low cost.

Claims: An apparatus for crushing things comprising: a casing (301) having an inlet (302) and an outlet (303); at least one first rotating member (304,314) and a second rotating member (305) rotatably mounted in the casing, axes of rotation thereof being in parallel with each other; means (307,317) for rotating the first and second rotating members; and a screw (310) fixed to an outer circumferential surface of the second rotating member (305); characterised in that: a plurality of cutting disks (309,319) are obliquely fixed to an outer circumferential surface of at least one first rotating member (304,314) at predetermined regular intervals so as to have a predetermined inclination with respect to the axis of the first rotating member; a plurality of blades (311) are spirally fixed to the outer circumferential surface of the second rotating member so that the blades intersect the screw; and a stationary blade (312) is fixed to an inner surface of the casing (301) so as to confront the second rotating member; whereby crushing operation is performed by the cutting disks and the screw, followed by further crushing operation by the blades on the second rotating member and the stationary blade. An apparatus according to claim 1, having two of said first rotating members.

Inventors: DOUMEN, SUSUMU, HAGA, TOSHIAKI, KUNISADA, TAKESHI
Applicants: KYOKUTO KAIHATSU KOGYO CO., LTD.
Application year: 1988
Main classification: B02C18
IPC codes: B02C19, B02C18