Soil modifying machine

Abstract: A soil modifying machine having a machine body (20) to which are disposed a soil hopper (28), a soil conveyer (27) for conveying a soil to be modified from the soil hopper (28), a soil conditioner supply device (29) for supplying a soil conditioner to the soil and a mixer (22) for crushing and mixing the conveyed soil and the soil conditioner to obtain a modified soil, wherein the mixer (22) is provided with a soil cutter device (32) and an impact hammer (33) and the soil cutter device (32) comprises a drum (45) and a cutter (46) mounted to an outer peripheral surface of the drum (45). The cutter (46) is disposed near an endless belt member (36) of the soil conveyer (27) to make small a gap between the endless belt member (36) and the drum (45) so that a large lump in the material soil having a large particle size does not pass this gap. According to such structure, since the large lump of soil does not fall to the impact hammer (33), the soil can be crushed and mixed by the impact hammer so that the soil conditioner can be fully infiltrated into the soil, thus the soil condition being effectively modified as a modified soil to be recycled as backfill or roadbed material.

Description: BACKGROUND OF THE INVENTION The present invention relates to a soil modifying machine for modifying or improving soil in a state of clay which is obtained by condensation and dewatering of muddy water generated at a crushing field, a shield-type tunnel excavating field or the like, such a modified soil being thereafter recycled as backfill (soil to be refilled) or roadbed material. Further, it is first to be noted that although the term "modify (modification or modified)" used herein may be substituted with "improve" or "ameliorate", the meaning thereof is to modify (improve or ameliorate) nature, form quality or the like of a soil. For example, Japanese Patent Laid-open (KOKAI) Publication No. HEI 11-169739 proposes such a soil modifying machine. This soil modifying machine generally comprises, as shown in Fig. 18, a machine body, not shown, a mixer 1, a modified soil conveyer 2, a soil conveyer 3, a soil conditioner supply device 4 and a soil hopper 5. In a such soil modifying machine, a soil to be modified 6, e.g., raw soil in the soil hopper 5 is conveyed to the mixer 1 through the material soil conveyer 3 and a soil conditioner is supplied from the soil conditioner supply device 4 to the soil 6 on the way of being conveyed by the soil conveyer 3. Thereafter, the soil 6 and the soil conditioner is supplied to the mixer 1 so as to be crushed and mixed, and the thus modified soil 7 is discharged out of the machine body by means of the modified soil conveyer 2. In such a soil modifying machine, the mixer 1 has an outer case (or housing) 10 in which a soil cutter cutting) device 11 as a primary mixer and a plurality of impact hammers (rotors having rotators) 12 are disposed so that the soil 6 conveyed by the soil conveyer 3 is cut off and dropped down by the soil cutter device 11 towards the impact hammers 12, and such soil and soil conditioner are crushed and then mixed by the impact hammers 12, thus performing the soil modification. The modified soil 7 is dropped down on the modified soil conveyer 2 through a discharge port 8. Another example of a soil modifying machine is described in WO97/25486, wherein the soil modifying machine has a machine body comprising a soil hopper, a soil conveyer for conveying a soil to be modified from the soil hopper, a soil conditioner supply device for supplying a soil conditioner to a soil, a mixer for crushing and mixing the conveyed soil and the soil conditioner to obtain a modified soil and a modified soil conveyer for conveying the modified soil. Incidentally, in the soil crushing field or site, raw stones which are collected from a mountain or the like, are crushed by a crusher, and mud component or like adhering or sticking to the crushed stones are washed and removed so that the crushed stones can be utilized as aggregate. The mud component removed in the above process is in a state of muddy water, which is then condensed and dewatered by a dehydrating (dewatering) press into a soil in the form of clay called as dewatered cake, which is then treated. When the dewatered cake is dried, fine particles scatter from its surface, and when the dewatered cake is wetted by rain water or like, it returns to the original muddy state. As mentioned above, the dewatered cake has a low strength, and hence, in a case where such dewatered cake is recycled as backfill or roadbed material, the fine particles thereof will be scattered on sunny days or will be wet and flowed on rainy days, thus being inconvenient. Accordingly, it is difficult to recycle the dewatered cake as the backfill or roadbed material, and hence, such dewatered cake is left as it is in the raw stone crushing filed or site in a mountain. The inventors of the subject application have tried to modify the soil condition by using a conventional soil modifying machine for recycling the dewatered cake as backfill or roadbed material, it was impossible to modify the soil condition to an extent suitable for recycling the dewatered cake as the backfill or roadbed material until the dewatered cake is very finely crushed and mixed with a solidifying agent because the dewatered cake has a low strength and is composed of a fine particle soil. Through the research and experiment of the inventors, thereafter, the following matters were found out. The soil cutter device 11 of the mixer 1 described above has a structure, as shown in Fig. 19A, that a plurality of cutters 14, each having a long scale, are mounted around a rotational shaft 13 so as to extend radially and to form widened V-shaped spaces 15 between the adjacent cutters 14 and the rotational shaft 13, respectively. When the rotational shaft 13 is rotated, the cutters 14 are also rotated to thereby cut off the soil 6 conveyed through the soil conveyer 3. During the above cutting operation, when lump of clay 16 which cannot be cut by the cutter 14 exists in the soil 6, as shown in Fig. 19A, the cutter 14 which collides with the clay lump 16, is rotated while pushing the clay lump 16 into the material soil 6 as shown in Figs. 19B and 19C and passes the clay lump 16 without cutting it. Thereafter, as shown in Fig. 19D, the next cutter 14 digs out the clay lump 16 and sputter it in a direction of the preceding cutter 14 into the V-shaped space 15 between this cutter 14 and the preceding cutter 14. When the cutter 14 is further rotated, the clay lump 16 between the space 15 drops down towards the impact hammers 12 as shown in Fig. 18. As mentioned hereinbefore, when the soil cutter device 11 of the conventional structure is utilized, the lump of clay 16 which cannot be cut off by the cutter may fall downward as it is towards the impact hammers 12, there increases a possibility of the clay lump having a large diameter being mixed with the cut soil 6. The clay lump having a large particle (soil) diameter has a worse infiltration of the soil conditioner. That is, in such a clay lump, even if the soil conditioner adheres to the outer surface of the clay lump, the soil conditioner hardly infiltrates thereinto, and hence, the inside central portion of the clay lump will maintain its clay state. As a result, in a case where the clay lump having a large diameter is mixed with the raw soil at a large mixing ratio, the soil conditioner cannot be sufficiently mixed with the soil, and hence, the modified soil which can be recycled as the backfill or roadbed material will not be obtainable. Furthermore, in the conventional structure, the impact hammer 12 comprises a central rotational shaft 17 and four hammer pieces (blades) 18 mounted thereon so as to extend radially, each hammer pieces 18 being a forged product in a fist-like shape. Because of such a structure, the hammer piece 18 has a not so-large beating surface for giving an impact to the materials to be mixed (soil to be modified and soil conditioner), and moreover, since the beating surface is curved, the materials will not be fully crushed by the impact, and the dewatered cake will not be made fine, thus maintaining a large percentage of existing clay lump having a large diameter to be mixed. Accordingly, in this case, as like as the aforementioned case, the soil conditioner cannot be sufficiently mixed with the soil to be modified, and hence, the modified soil which can be recycled as the backfill or roadbed material will not be obtainable. SUMMARY OF THE INVENTION An object of the present invention is to substantially eliminate defects or drawbacks encountered in the prior art mentioned above and to provide a soil modifying machine for obtaining a modified soil which can be recycled as backfill or roadbed material by mixing soil in the form of clay such as dewatered cake and a soil conditioner. The inventors of the subject application have searched and experienced in view of the prior art mentioned above and found out that the soil could be finely granulated by improving a shape of a soil cutter device of a mixer to be a modified soil which can be recycled as backfill or roadbed material. Further, the inventors have found out that the soil could be finely granulated by improving a shape of an impact hammer of a mixer to be a modified soil which can be recycled as backfill or roadbed material. Furthermore, the inventors have also found out that the once modified soil can be further finely granulated by again mixing it by another mixer disposed downstream side of the first mentioned mixer to thereby be a modified soil which can be effectively recycled as backfill or roadbed material. The above and other objects can hence be achieved according to the present invention by providing a soil modifying machine having a machine body to which are disposed a soil hopper, a soil conveyer for conveying a soil to be modified from the soil hopper, a soil conditioner supply device for supplying a soil conditioner to the soil, a mixer for crushing and mixing the conveyed soil and the soil conditioner to obtain a modified soil and a modified soil conveyer for conveying the modified soil, the soil modifying machine being characterized in that a rear side mixer is disposed for further crushing and mixing the modified soil discharged from the modified soil conveyer. According to this structure, the soil and the soil conditioner are once crushed and mixed by the mixer to be the modified soil, which is thereafter further crushed and mixed by the rear side mixer to be the modified soil having a small particle size (diameter) even if the soil once modified by the mixer has a comparatively large particle size, whereby the soil conditioner can fully infiltrate into the soil to be modified, thus achieving an excellent soil modifying function. Therefore, the thus obtained modified soil can be effectively recycled as backfill or roadbed material. Furthermore, there causes a case where the modified soil discharged from the mixer includes a large sized soil particle lump formed of a plurality of small sized ones at a time of being conveyed through the modified soil conveyer. However, in such a case, such large sized soil particles can be again crushed and mixed by the rear side mixer into small sized ones. Thus, the modified soil discharged from the rear side mixer is composed of small sized particles which can be surely visually observed as finely modified soil. In this structure, the rear side mixer may be disposed at a discharge portion of the modified soil conveyer. According to this structure, the rear side mixer can be moved together with the machine body. Furthermore, in this structure, the rear side mixer is disposed independently of the machine body and disposed downstream side of the modified soil conveyer. According to this structure, the rear side mixer can be arranged or removed in accordance with the condition of the soil to be modified. The nature and further characteristic features of the present invention will be made more clear from the following descriptions made with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings: Fig. 1 is a side view showing a general structure of a self-advancing (crawler-type) soil modifying machine; Fig. 2 is an illustration showing an essential structure of the soil modifying machine according to a first embodiment of the present invention; Fig. 3 is a side view showing a first example of a rear side mixer, in an enlarged scale, of the first embodiment of Fig. 2; Fig. 4 is a plan view of Fig. 3; Fig. 5 is a sectional view taken along the line XIX-XIX of Fig. 3; Fig. 6 is a side view of a rotary cutter device of the rear side mixer of the first embodiment; Fig. 7 is a side view showing a second example of a rear side mixer, in an enlarged scale, of the first embodiment of Fig. 2; Fig. 8 is a plan view of Fig. 7; Fig. 9 is a side view showing a third example of a rear side mixer, in an enlarged scale, of the first embodiment of Fig. 2; Fig. 10 is a perspective view of a plate shown in Fig. 9; Fig. 11 is a side view showing a fourth example of a rear side mixer, in an enlarged scale, of the first embodiment of Fig. 2; Fig. 12 is a side view showing a fifth example of a rear side mixer, in an enlarged scale, of the first embodiment of Fig. 2; Fig. 13 is an illustration showing an essential structure of the soil modifying machine according to a second embodiment of the present invention; Fig. 14 is an illustration showing an essential structure of the soil modifying machine according to a third embodiment of the present invention; Fig. 15 is an illustration showing an essential structure of the soil modifying machine according to a fourth embodiment of the present invention; Fig. 16 is an illustration showing an essential structure of the soil modifying machine provided with another example of a soil conditioner supply device; Fig. 17 is a sectional view of a mixer and a material soil conveyer of another example; Fig. 18 is an illustration showing an essential structure of the soil modifying machine having a conventional structure; and Figs 19A to 19D include views explaining an operation of a soil cutter device of a conventional structure. DESCRIPTION OF THE PREFERRED EMBODIMENTS (General Construction of Soil Modifying Machine) As shown in Fig. 1, a self-advancing machine (crawler-type vehicle) is constructed by a machine body 20 and a traveling members 21, 21 such as crawlers mounted to both lateral sides of the machine body 20. A mixer 22 is mounted to intermediate portion of the machine body 20 in the longitudinal direction thereof (vehicle traveling direction). Moreover, a power source unit 23 including an engine, hydraulic pump and the like is disposed at a front portion (right side as viewed in Fig. 1) of the machine body 20 and is covered by a cover 24. Further, in the illustrated embodiment, although the traveling members 21 are crawlers, a wheel-type structure may be instead adopted. A boarding platform 25 is also provided for the machine body 20. A mount frame 26 is mounted to the machine body 20 at a portion on the rear side thereof so as to project rearward (left side as viewed) from the machine body 20, and a soil conveyer 27 for conveying a soil to be treated, e.g., a raw soil is also mounted to the mount frame 26 so as to extend in the longitudinal direction thereof. Furthermore, a soil hopper 28 is mounted to the mount frame 26 at a rear side upper portion of the soil conveyer 27. A soil conditioner supply device 29 is also mounted between the hopper 28 and the mixer 22 so as to cover the front side portion of the soil conveyer 27. A modified soil conveyer 30 is mounted to a lower portion of the machine body 20 so as to extend in the longitudinal direction thereof. Further, as shown in Fig. 1, the modified soil conveyer 30 has one side portion (rear side portion) in the conveying direction, and this one side portion is positioned below the mixer 22 and has another side portion (front side portion) in the conveying direction, which extends forward over the machine body 20. Although, in the described embodiment, the machine body 20 is mounted to the traveling member 21 such as crawlers, the soil modifying machine of the present invention may be constructed as a stationary soil modifying machine provided with no traveling member. (Structure of Soil Modifying Machine of First Embodiment) A first embodiment of the soil modifying machine according to the present invention is generally shown in Fig. 2. With reference to Fig. 2, the structures of the mixer 22, the soil conveyer 27, the soil hopper 28, the soil conditioner supply device 29 and the modified soil conveyer 30 have substantially the same as those of the conventional ones. In this first embodiment, another mixer, which is called hereinlater as rear (or rear side) mixer 60 is arranged at a convey-out (discharge) portion of the modified soil conveyer 30 downstream side (i.e. rear side) of the former mixer 22. This rear mixer 60 acts to again crush and mix the modified soil which has been once crushed by the former mixer 22 and conveyed through the modified soil conveyer 30. According to such an arrangement of the rear mixer 60, in a case where the soil crushed and modified by the mixer 22 still includes lumps having a large particle size, for example, in a mixing ratio of 20% of such large lumps, such large lumps can be effectively crushed and mixed by the rear mixer 60 so as to reduce the included large lumps, for example, in a mixing ratio of 5 to 10%. Accordingly, the infiltration of the soil conditioner into the material soil can be sufficiently improved, and the modified soil can be recycled and utilized as the backfill, roadbed material or like. The specific structure of this rear (rear side) mixer 60 will be explained hereunder. The modified soil conveyer 30 comprises, as shown in Fig. 2, a driving pulley 61, a driven pulley 62 and a belt wound around these pulleys in an endless manner With reference to Figs. 3 and 4, the driving pulley 61 is mounted to be rotatable between one end portions of the longitudinal direction of a pair of conveyer frames 64, and this driving pulley 61 is driven and rotated by a motor 65 for driving the conveyer mounted to one side conveyer frame 64. A conveyer cover 66 having approximately U-shaped in section is also mounted between the paired conveyer frames 64. To the one end portions of the paired conveyer frames 64 mentioned above, there are mounted brackets 61, respectively, by means of bolts 68, to which the rear mixer 60 is mounted. The bracket 67 has a plate shape having a downward projection, as mount portion 69, extending downward over the driving pulley 61. The rear mixer 60 has a frame body 70 which is mounted to the mount portion 69 of the bracket 67. The frame body 70 has a U-shaped plan view and is composed of a pair of long-scaled transverse members 71 and a connection member 72 mounted to one longitudinal end portions of both the transverse members 71 so as to cross the same. The paired transverse members 71 are secured to the mount portions 69 of the paired brackets 67 for the rear mixer 60, respectively. As shown in Fig. 5, a rotational shaft 73 crosses and is rotatably supported between the longitudinal other end portions of the paired transverse members 71 of the frame body 70. This rotational shaft 73 is driven and rotated by a motor 74 mounted to one of the transverse members 71. Furthermore, as shown in Figs. 5 and 6, a plurality of brackets 75 are fixed to the rotational shaft 73 with an axial interval from each other, and these brackets 75 are provided with a plurality of mount portions 75a, respectively so as to extend radially therefrom. A plurality of cutters 76 are mounted to the respective mount portions 75a of the brackets 75 through collars 77 with an axial interval from each other. These cutters 76, brackets 75 and rotational shaft 73 constitute a rotary cutter device 78 in the manner that the plural cutters 76 are arranged so as to extend radially with an interval from each other, and the cutter 76 has a plate structure having a thickness of 4.5 mm and the adjacent cutters 76 are arranged with an interval (distance) of 22 mm therebetween. A cover member 80 for covering the cutter device 78 is attached to the frame body 70. This cover member 80 comprises a front plate 81, a rear plate 82 and a pair of side plates 83 so as to provide a box-shaped structure having upper and lower openings, and the side plates 83 are secured to portions surrounding rotational shaft supporting portions of the paired transverse members 71 of the frame body 70 through ring-shaped spacers 84, respectively. The upper opening 80a of the cover member 80 is connected to the conveyer cover member 66 and the lower opening 80b is opened downward. According to the arrangement mentioned above, since the rotational shaft 73 (i.e. rotation center) of the rotary cutter device 78 is shifted, in position, apart from the driving pulley 61 (i.e. discharge portion of the modified soil conveyer 30) towards the downstream side in the conveying direction, the modified soil conveyed by the conveyer 63 falls on the driving pulley side 61 rater than the rotational shaft 73 of the cutter device 78. The modified soil crushed and mixed by the mixer 22 is conveyed on the belt member 63 of the modified soil conveyer 30, then falls downward at the discharge portion thereof on the driving pulley 61 side rather than the rotational shaft 73 side of the cutter device 78 of the rear side mixer 60 and collides with the cutters 76 which are rotating in arrowed directions as shown in Fig. 3, whereby the modified soil can be further crushed and mixed. In this operation, the lump of soil having a particle size smaller than the interval between the adjacent cutters 76 passes therebetween and falls therefrom. As mentioned above, the modified soil colliding with the cutter 76 is sputtered by the rotation of the cutter 76 and collides with the rear plate 82 of the cover member 80, thus being again crushed and mixed. Furthermore, the modified soil once colliding with the rear plate 82 of the cover member 80 again collides with the cutter 76 and is crushed and mixed, and thereafter, the further crushed modified soil falls and is discharged through the lower opening 80b of the cover member 80. The minimum interval (distance) between the rear plate 82 of the cover member 80 and the cutter 76 is set to a value of, for example, less than 20 mm, so that the lump of soil having a large particle diameter does not pass therebetween without colliding with the cutter 76. As mentioned above, since the modified soil can be again crushed and mixed by the rear side mixer 60, the lump of the modified soil having a large particle diameter can be again crushed to thereby reduce the mixing ratio of the amount of the large lump of the modified soil in the soil crushed by the rear side mixer 60, whereby such modified soil can be effectively utilized as backfill, roadbed material or like. Accordingly, even in a case where the modified soil which is obtained by crushing and mixing the soil to be modified and the soil conditioner by the mixer 22 includes much lump of soil having a large particle diameter size by the amount not recycled and usable as modified soil, the mixing ratio of such large particle sized lump of soil can be reduced by further crushing and mixing the once modified soil by the rear side mixer 60, such mixing ratio can be reduced, for example, to less than 5 % of the included amount of lump of soil having a particle diameter of more than 20 mm. Such further modified soil can be recycled as backfill or roadbed material. In the former embodiment, although the cutter device 78 of the rear mixer 60 is rotated by the motor 74, it may be driven and rotated by the conveyer motor 65 for the modified soil conveyer 60. For example, as shown in Figs. 7 and 8, a pulley 85 is mounted to a shaft 61 a of the driving pulley 61 and another pulley 86 is mounted to the rotational shaft 73 of the rotational cutter device 78. A belt is wound around these pulleys 85 and 86 and the cutter device 78 is rotated by the conveyer motor 65. Further, impact hammers 33 of the mixer 22 may be utilized in place of the rotational cutter device 78. Moreover, the rear side mixer 60 may merely have a structure with which the falling modified soil collides and is crushed. For example, as shown in Fig. 9, mounting brackets 88 are fixed to the conveyer frames 64 and a plate 89 is fixed to the mounting brackets 88 at an attitude inclined obliquely downward with respect to the horizontal attitude. The modified soil c falling from the conveyer belt 63 collides with the plate 89 to be thereby crushed and mixed, and then, falls along the plate 89. In such case, although the crushing and mixing ability is reduced in comparison with the case that the rear side mixer 60 provided with the cutter device 78 in the cover member 80 is used, it is possible to obtain the modified soil including lump of soil having a particle diameter of for example, more than 20 mm at a mixing ratio of about 10%. The plate 89 may take a structure, as shown in Fig. 10, that raised pieces 89b are formed to both side edges of a bottom plate 89a. According to this structure, the modified soil falling down and colliding with the plate 89 is not scattered therearound and can be moved downward along the bottom plate 89a. Further, in the structure of the embodiment mentioned above, although the rear side mixer 60 is secured to the modified soil conveyer 30, it may be disposed separately therefrom. For example, as shown in Fig. 11, the rear side mixer 60 may be composed of a secondary belt conveyer 90 disposed downstream side of the modified soil conveyer 30, a housing 92 is mounted, through a bracket 93, to a conveyer frame 91 of the secondary conveyer 90, and the rotational cutter device 78 of the structure mentioned above is disposed inside the housing 92. According to such a structure, the modified soil c conveyed by the modified soil conveyer 30 falls inside the housing 92 and collides with the cutter 76 arranged at a portion near the conveyer 30 rather than the rotational shaft 73. The modified soil sputtered by the cutter 76 collides with a rear wall section 92a of the housing 92 and again collides with the cutter 76. Thereafter, the crushed modified soil is discharged. Furthermore, as shown in Fig. 16, the housing 92 may be attached to a frame structure 94 through a bracket 95, and the frame structure 94 may be made movable by attaching wheels 96 thereto. According to such structure, the rear mixer 60 can be easily moved to a portion lower than the discharge portion of the modified soil conveyer 30 to again crush and mix the once modified soil c. discharged through the conveyer 30. Still furthermore, with reference to Figs. 11 and 12, the rear side mixer 60 is disposed below the discharge portion of the modified soil conveyer 30, a further conveyer means may be disposed downstream side of the modified soil conveyer 30 and the rear mixer 60 is located to a discharge portion of this further disposed conveyer. In such arrangement, substantially the same function as that in the case of Figs. 11 and 12 will be attained. The rear side mixer 60 may have a structure in which impact hammers 33 are disposed inside the housing 92 in place of the cutter device 78. (Structure of Soil Modifying Machine of Second Embodiment) A second embodiment of the soil modifying machine according to the present invention is generally shown in Fig. 13, in which the soil cutter device of the mixer 22 is made as drum-type soil cutter device and the rear side mixer 60 is arranged to the discharge portion of the modified soil conveyer 30. According to the structure of this embodiment, the mixing ratio of the large sized soil particles (having a diameter of more than 20 mm) in the modified soil c discharged from the rear side mixer 60 is less than 5%. Accordingly, the thus obtained modified soil can be adequately recycled as backfill or roadbed material. (Structure of Soil Modifying Machine of Third Embodiment) A third embodiment of the soil modifying machine according to the present invention is generally shown in Fig. 14, in which the impact hammer 33 of the mixer 22 is made as plate-type hammer 33 and the rear side mixer 60 is arranged to the discharge portion of the modified soil conveyer 30. According to the structure of this embodiment, the mixing ratio of the large sized soil particles (having a diameter of more than 20 mm) in the modified soil c discharged from the rear side mixer 60 is less than 5%. Accordingly, the thus obtained modified soil can be adequately recycled as backfill or roadbed material. (Structure of Soil Modifying Machine of Fourth Embodiment) A fourth embodiment of the soil modifying machine according to the present invention is generally shown in Fig. 15, in which the soil cutter device 32 of the mixer 22 is made as drum-type soil cutter device 32, the impact hammer 33 is made as the plate-type impact hammer 33 and the rear side mixer 60 is arranged to the discharge portion of the modified soil conveyer 30. According to the structure of this embodiment, the large sized soil particles (having a diameter of more than 20 mm) less remains in the modified soil c discharged from the rear side mixer 60. Accordingly, the thus obtained modified soil can be adequately recycled as backfill or roadbed material. (Structure of Soil Modifying Machine of Fifth Embodiment) An fifth embodiment of the soil modifying machine according to the present invention is generally shown in Fig. 16, in which the soil conditioner supply device 29 is composed of a nozzle 100 arranged near a charging port 37 of the mixer 22 and a liquid soil conditioner is jetted to the soil to be modified on the conveyer 27 through the nozzle 100. Such nozzle 100 may be disposed inside the case 31 of the mixer 22 as shown with a virtual line. Such arrangement of the soil conditioner supply device 29 may be applied to the respective embodiments mentioned hereinbefore. (Structure of Soil Modifying Machine of Sixth Embodiment) A sixth embodiment of the soil modifying machine according to the present invention is partially shown in Fig. 17, in which the soil conveyer 27 is formed of a plate member so that the soil slides downward along the plate member by its self-gravity. Such soil conveyer 27 may be applied to the respective first to fourth embodiments mentioned hereinbefore. It is to be noted that the present invention concerning the soil modifying machine is not limited to the described embodiments and many other changes, modifications and organic combinations may be made without departing from the scopes of the appended claims.

Claims: A soil modifying machine having a machine body (20) to which a soil hopper (28), a soil conveyer (27) for conveying a soil to be modified from the soil hopper (28), a soil conditioner supply device (29) for supplying a soil conditioner to a soil, a mixer (22) for crushing and mixing the conveyed soil and the soil conditioner to obtain a modified soil and a modified soil conveyer (30) for conveying the modified soil are disposed, characterized in that a rear side mixer (60) is disposed for further crushing and mixing the modified soil discharged from the modified soil conveyer (30). A soil modifying machine according to claim 1, wherein said rear side mixer (60) is disposed at a discharge portion of the modified soil conveyer (30). A soil modifying machine according to claim 1, wherein said rear side mixer (60) is disposed independently of the machine body (20) and disposed downstream side of the modified soil conveyer (30).

Inventors: KAMOSHIDA YASUHIRO, YOSHIDA YASUHIRO, KAMOSHIDA, YASUHIRO, YOSHIDA, YASUHIRO, Kamoshida, Yasuhiro, Komatsu Ltd., Yoshida, Yasuhiro, Komatsu Ltd.
Applicants: KOMATSU MFG CO LTD, KOMATSU LTD.
Application year: 2000
Main classification: E02D3
IPC codes: E02F7, B02C21, E01C21, E02F5, E02D3, B01F7, B02C18