Patent Application
20070284465
Embodiments of a crusher according to the present invention will be described below with reference to the drawings.
The crusher shown in
The travel body 1 comprises a track frame 5, a drive wheel 6 and a driven wheel 7 disposed respectively at longitudinal opposite ends of the track frame 5, a driving unit (hydraulic motor for travel) 8 having an output shaft coupled to a shaft of the drive wheel 6, and a crawler (caterpillar belt) 9 looped over the drive wheel 6 and the driven wheel 7. A body frame 10 is disposed on the track frame 5. The body frame 10 supports the crushing function structure 2, the discharge conveyor 3, the power unit 4, etc.
The crushing function structure 2 comprises a hopper 11 for receiving the loaded target materials, a feed conveyor 12 (see
The feed conveyor 12 conveys the target materials toward a crushing rotor 15 (described later), and it comprises a sprocket-like drive wheel 16 (see
The pressing feeder unit 14 is provided adjacently rearward of the crushing rotor 15 (described later) above the feed conveyor 12 in an opposed relation to its conveying surface. With such an arrangement, the pressing feeder unit 14 introduces the target materials on the feed conveyor 12 toward the crushing rotor 15 while pressing the target materials from above. On that occasion, an anvil (first fixed bit) 70 (described later) presses the target materials toward the feed conveyor 12 side for crushing of the target materials.
The pressing feeder unit 14 comprises a support member (arm) 23 which has a rotary shaft 22 supported above the crushing apparatus 13 by a bearing provided in the side cover 20 such that the support member 23 is rotatable in a vertical plane (i.e., swingable up and down), a pressing roller 24 provided rotatably relative to the support member 23 and introducing the target materials to be crushed toward the crushing rotor 15 while pressing the target materials on the feed conveyor 12 from above, and the anvil 70 disposed at a position which is closer to the crushing rotor 15 than a point where the pressing roller 24 presses the target materials and which is outward of the crushing rotor 15 in the radial direction. The anvil 70 has a bumping surface 71, against which the target materials bump, disposed in an opposed relation to the rotating direction of a crushing bit 36 (described later).
The support member 23 comprises an arm portion 25 provided with the rotary shaft 22, and a bracket portion 26 provided at the distal end side of the arm portion 25 and supporting the pressing roller 24. A lower end surface of the arm portion 25 is formed to curve in a circular-arc shape, and a curved plate 28 defining a part of a crushing chamber 27 (described later) is attached to the curved lower end surface of the arm portion 25. On the other hand, a mount area of the bracket portion 26 to which the pressing roller 24 is mounted is formed in a circular-arc shape having a smaller diameter than the pressing roller 24 such that an outer circumferential surface of the pressing roller 24 projects out of the bracket portion 26.
The dimension of the pressing roller 24 in the transverse direction (i.e., in the direction perpendicular to the drawing sheet of
The bracket portion 26 has a projected portion 80 which is projected into the crushing chamber 27 in a direction toward the crushing rotor 15 (described later). The projected portion 80 includes a wall 81 which is extended in the transverse direction of a crusher body and covers the pressing roller 24 from the crushing chamber 27 side, and also includes a recess 82 formed at the lower end (at the side closer to the feed conveyor 12) of the wall 81 so as to face the crushing chamber 27. A bracket 84 having a protrusion 83 (see
The anvil (first fixed bit) 70 has a bumping surface 71 against which the target materials bump, the bumping surface 71 being disposed in an opposed relation to the rotating direction of the crushing bit 36 (described later), a recess 72 (see
The anvil 70 will be described in more detail below with reference to
Referring to
The bumping surface 71 of the anvil 70 is disposed at a level not lower than the height of the contact portion 91 (i.e., not lower than a position above the conveying surface of the feed conveyor 12 by the height h), and it is arranged such that, in the crushing posture, the normal line n is directed to the rear side of the crusher body (i.e., the lower left direction in
Also, the anvil 70 is preferably mounted to the bracket portion 26 such that, during the crushing operation, a part of the bumping surface 71 is positioned at a level of the height h. With such an arrangement, when the crushing bit 36 smashes against the target materials 90 introduced to the crushing chamber 27, the anvil 70 restricts the target materials 90 from being raised upward, whereby energy of the bumping can be efficiently utilized as crushing energy. Hence the crushing efficiency is increased.
Returning to
The crushing apparatus 13 is mounted substantially on a central portion of the body frame 10 (see
The crushing rotor 15 is rotatably supported by bearings (not shown) each of which is mounted to, e.g., the side cover 20 of the crushing apparatus 13 (or a not-shown support member separately provided on the body frame 10). A plurality of support members 35 and crushing bits (i.e., smashing plates or crushing blades) 36 mounted respectively to the support members 35 are provided on an outer circumferential surface of the crushing rotor 15. The crushing bits 36 are arranged such that their edge faces precede the corresponding support members 35 when the crushing rotor 15 is rotated in the forward direction. Also, the crushing bits 36 are fixed to the support members 35 by bolts 37 or the likes, and therefore they are easily replaceable when worn out.
Outward of the crushing rotor 15 in the radial direction, the curved plate 28, the anvil 34, and a screen (sieve member) 38 are successively disposed in this order from a point where the target materials to be crushed are introduced toward the crushing rotor 15 (i.e., from a position near the surrounding of the pressing roller 24) in an upstream-to-downstream direction in which the target materials are carried (i.e., in the forward rotating direction of the crushing bits 36). The crushing chamber 27 is a space substantially defined by the curved plate 28, the anvil 34, the screen 38, etc. The crushing chamber 27 is opened at the same side as both the feed conveyor 12 and the pressing feeder unit 14 (i.e., the left side as viewed in
The anvil (second fixed bit) 34 has a surface (bumping surface) 60 against which the target materials introduced to the crushing chamber 27 bump, and it is mounted to a holding member 40 such that the bumping surface 60 is positioned in an opposed relation to the rotating direction of the crushing rotor 15. The holding member 40 has a rotary shaft 41 and is coupled through a shear pin 43 to a support member 42 fixed to the side cover 20. For example, when an impact load exceeding an allowable value of the shear pin 43 is applied to the anvil 34, the shear pin 43 is broken and the holding member 40 is released from a restricted state. Thus, the holding member 40 is rotated about the rotary shaft 41 to retreat from the crushing chamber 27.
The screen (sieve member) 38 has discharge holes (not shown) for discharging the materials having been crushed outward of the crushing chamber 27 while selecting the grain size of the crushed materials, and it is held at a position around the crushing rotor 15 by a frame-like screen holding member (screen holder) 44. The screen holding member 44 has a rotary shaft 45 provided at one end of the screen holding member 44 on one side (i.e., the left side as viewed in
The discharge conveyor 3 mainly comprises a frame 50, a conveyor cover 51 disposed over a conveyor belt (not shown) looped between a drive wheel (not shown) and a driven wheel (not shown) which are disposed at opposite ends of the frame 50 in the longitudinal direction thereof, a driving unit 52 (i.e., a hydraulic motor for the discharge conveyor) for rotating the drive wheel. A portion of the discharge conveyor 3 on the discharge side (i.e., its portion on the front side or the right side as viewed in
The power unit 4 is mounted on an end portion of the body frame 10 on the other side in the longitudinal direction (i.e., on the right side as viewed in
The operation of the crusher according to the first embodiment will be described below.
When target materials to be crushed are loaded into the hopper 11 by a heavy machine (such as a hydraulic excavator) equipped with an appropriate working device, e.g., a grapple, the target materials are dropped to be put on the running members 17 of the feed conveyor 12 while being guided by a spreading portion of the hopper 11. Then, the target materials are substantially horizontally conveyed toward the front side of the crusher with circulating motion of the running members 17. When the target materials on the feed conveyor 12 are conveyed to a position near the pressing feeder unit 14, they come into under the pressing roller 24 and push up the pressing feeder unit 14. Then, the target materials pushing up the pressing feeder unit 14 are introduced to the crushing chamber 27 while they are pressed toward the feed conveyor 12 side under the action of dead weight of the pressing feeder unit 14. At that time, the target materials are projected into the crushing chamber 27 in a cantilevered state with their ends gripped between the pressing roller 24 and the feed conveyor 12 to serve as support points.
The projected material portions are smashed from below by the crushing bits 36 of the rotating crushing rotor 15 rotating at a high speed, whereby the target materials are going to be pushed up. At that time of smashing, the anvil 70 positioned above the target materials acts as not only a support point for restricting the smashed target materials from being moved upward and for pressing the target materials toward the feed conveyor 12 side, but also as a fixed bit for crushing the target materials by shearing in cooperation with the crushing bits 36. Accordingly, the target materials are finely crushed, i.e., subjected to primary crushing.
The target materials having been thus subjected to the primary crushing are forced to move through the crushing chamber 27 in the rotating direction of the crushing rotor 15 until the anvil 34. The target materials are further finely crushed, i.e., subjected to secondary crushing, by the anvil 34. The target materials having been thus subjected to the secondary crushing are forced to pass through a space formed between the anvil 34 and the crushing rotor 15 with the rotation of the crushing rotor 15, and to reach a position near the screen 38.
Of the target materials having reached the screen 38, those materials having sizes smaller than the diameter of the discharge holes are discharged at once from the crushing chamber 27 through the screen 38, while those materials having sizes larger than the diameter of the discharge holes continue to circulate in the crushing chamber 27 and are repeatedly smashed by the crushing bits 36 and bumped against the anvil 34 and an inner wall surface of the crushing chamber 27 so that the target materials are gradually crushed into target grain sizes (i.e., tertiary crushing). The crushed materials (crushed chips) discharged from the crushing chamber 27 are dropped onto the conveyor belt of the circulating discharge conveyor 3 through a chute (not shown). The crushed materials having dropped onto the conveyor belt are conveyed toward the front side (i.e., the right side as viewed in
The advantages of the crusher according to the first embodiment will be described below.
For easier understanding of the advantages of the first embodiment, a crusher in which the pressing feeder unit includes no fixed bit corresponding to the anvil 70 used in the first embodiment is assumed to be a comparative example. Generally, in crushers, along with the crusher of the first embodiment, using the crushing method of smashing the crushing bit against the target materials to be crushed from below, which are introduced by the running members of the feed conveyor or the like, the target materials can be crushed into finer chips when a point (support point) where the target materials to be crushed are pressed and supported from above is positioned closer to a point (smashing point) where the crushing bit smashes against the target materials to be crushed. In the crusher of the comparative example, the support point where the target materials to be crushed are supported is a contact point between the pressing roller and the target materials (which corresponds to the contact portion 91 in the first embodiment). In trying to position the support point closer to the smashing point, however, there is a limit because of the problem with mechanical layout, e.g., the arrangement of the pressing roller and the crushing rotor. Thus, in the crusher of the comparative example, because of a limit in trying to position the support point and the smashing point closer to each other, a difficulty arises in crushing the target materials into chips finer than a certain level with the primary crushing by the crushing bit, and the target materials tend to be roughly crushed. In some cases, a longer time is required until the roughly-crushed target materials are finely crushed, and the crushed materials having relatively large sizes are discharged through the screen as they are. This may result in lowering of the crushing efficiency and a reduction in grain size quality of the crushed materials.
In contrast, in the crusher of this first embodiment, the pressing feeder unit 14 has the anvil 70 which is disposed at a position closer to the crushing rotor 15 than the contact portion 91 where the pressing roller 24 presses the target materials, and which is disposed at a position outward of the crushing rotor 15 in the radial direction. The bumping surface 71 of the anvil 70 against which the target materials bump is arranged in an opposed relation to the rotating direction of the crushing bits 36. Further, when the crushing bits 36 smash against the target materials introduced toward the crushing rotor 15, the anvil 70 presses those target materials toward the feed conveyor 12 side for crushing thereof. With such an arrangement, the anvil 70 acts not only as a fixed bit at an inlet of the crushing chamber 27, but also as a support point for pressing the target materials at a position closer to the crushing rotor 15 than the contact portion 91 of the pressing roller 24. Therefore, the support point and the smashing point can be located closer to each other than the case of the comparative example, and the crushed materials having smaller grain sizes can be obtained even in the primary crushing. As a result, the target materials can be more effectively crushed by the crushing bits 36, and the crushed materials having good grain size quality can be produced with higher efficiency.
Also, in the crusher of this first embodiment, the target materials crushed by the anvil 70 are further crushed, as described above, by the anvil 34 disposed downstream of the anvil 70 in the direction in which the target materials are forced to move in the crushing chamber 27. Accordingly, the target materials can be even more efficiently crushed by the interaction of both the fixed bits.
A modification of the first embodiment will be described below.
The modification of the first embodiment described below is featured in that the bumping surface 71 of the anvil 70 is arranged to have a difference posture during the crushing operation from that in the crusher of the first embodiment.
Referring to
By mounting the anvil 70A to the bracket portion 26 with the normal line n being directed vertically downward during the crushing operation as shown in
As another modification similar to the above-described modification, the anvil may be mounted such that the normal line n with respect to the bumping surface 71 is directed forward of the crusher body in the crushing posture. Such an arrangement is particularly advantageous in that, when the target materials are loaded, they can be smoothly introduced into the crushing chamber 27 without being caught by the edge of the anvil.
A second embodiment of the present invention will be described below. As compared with the first embodiment, the second embodiment is featured in that the anvil (first fixed bit) has two or more bumping surfaces.
Referring to
By performing the crushing operation with the thus-constituted anvil 70B mounted in place, when the crushing bits 36 smash against the target materials, the target materials are first crushed by the first edge 74a and are then crushed by the second edge 74b. Thus, since the target materials are crushed in two steps by the anvil 70B, the crushing efficiency is increased.
Another example of the anvil having two bumping surfaces is shown in
An example of the anvil having three bumping surfaces is shown in
By forming three bumping surfaces as described above, a plurality of edges (particularly, the first edge 74a and the third edge 74c) are also formed, and therefore the target materials can be crushed in plural steps substantially in a similar manner to that described above. Further, by forming bumping surfaces in number over three, e.g., four bumping surfaces, so as to provide two angular protrusions, a plurality of edges can be formed appropriately as in the above-described example. Thus, even in the case of three or more bumping surfaces, it is possible to crush the target materials in plural steps and to increase the crushing efficiency.
A third embodiment of the present invention will be described below. This third embodiment is featured in having a support-point constituting portion which positively acts on the target materials as a support point, instead of the anvil 70 which acts as the support point and the fixed bit in the above-described first embodiment.
Referring to
A fourth embodiment of the present invention will be described below. This fourth embodiment is featured in making, in the anvil 70 of the first embodiment, adjustable a distance (hereinafter referred to as a “gap size D”) from an inner end of the anvil in the radial direction of the crushing rotor 15 to a maximum locus R (described later) of rotation of the crushing bits 36.
Referring to
The anvil 70E has a side surface 73E which is projected into the crushing chamber 27 in the position during the crushing operation, shown in
Further, in the crusher of this fourth embodiment, in addition to the above-described anvil 70E having the edge 74E, there are prepared other plural types of anvils (not shown) which have edges with different distances (sizes D) up to the maximum rotation locus R. In the crusher of this fourth embodiment, the gap size D can be adjusted by replacing the plural types of anvils from one to another as required. Thus, since the gap size D can be adjusted to a value suitable for the desired grain size of the crushed materials, it possible to improve the grain size quality of the crushed chips and to increase the crushing efficiency. The above description has been made in connection with the case of adjusting the distance from the edge 74E to the maximum rotation locus R in the posture during the crushing operation. However, when another part of the anvil is positioned closest to the maximum locus R of rotation of the crushing bits 36 in the radial direction of the crushing rotor 15, a similar advantage to the above-described one can also be of course obtained by adjusting the gap size D on the basis of such a part of the anvil.
Moreover, the above description has been made of, by way of example, the case where the present invention is applied to a self-propelled crusher, but the present invention is not limited to such an application. As a matter of course, the present invention is also applicable to, e.g., a mobile crusher capable of traveling with traction, a transportable crusher capable of being lifted by, e.g., a crane for transportation, and a stationary crusher installed as a fixed machine in a plant or the like. Any of those applications can also provide similar advantages to those obtainable with the above-described embodiments. In addition, the crusher of the present invention can be used to crush woods, waste plastics, waste tatami (straw matting), bamboos, etc. as target materials, and can provide similar advantages to those described above regardless of the type of target materials to be crushed.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2006-158536 | Jun 2006 | JP | national |
