JP3234114U - Excavator and rotary excavator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To deal with both soft layers and hard rocks without replacement of equipment, to save extra labor and time required for replacement work, and to excavate hard rocks with relatively low noise and low vibration. Provided are an excavator and a rotary excavator capable of performing excavation work. A rotary excavator 1 includes an excavator 2a and a rotary drive device 8. The excavator is a cylindrical casing 3 that can rotate in the circumferential direction of the shaft, a drive unit that is housed in the casing and can supply a driving force, and is arranged around the rotation axis of the casing to receive the driving force of the casing. It contains multiple excavation bits that can move forward and backward along the axial direction, and the striking force exerted by the excavation bit under the driving force differs for each excavation bit, or at least one excavation bit is another excavation bit. It is provided with a group of excavation bits set in any aspect, which is different from the above. [Selection diagram] Fig. 1

Description

The present invention relates to an excavator and a rotary excavator. More specifically, it is possible to deal with both soft layers and hard rock formations or hard rock boulders (hereinafter collectively referred to as "hard rocks") without replacing the equipment, and the extra work required for the replacement work is required. The present invention relates to a material that can save time and, in addition, can perform excavation work with relatively low noise and low vibration even when excavating hard rock.

In recent years, especially in construction work in urban areas, vibration and noise generated during excavation work due to pile driving of foundation piles have become a problem, and in order to solve this problem, the present inventors have described the following Patent Document 1 The rotary excavator described in is proposed. FIG. 17 shows the excavator of this rotary excavator as the excavator 9.

The excavation device 9 is subjected to a rotary motion by a rotary drive device (not shown) to perform excavation work (hereinafter referred to as “rotary excavation work”), and the diameter of the excavation device 9 is attached to the excavation side end of the excavation device 9. Smaller than, and has a plurality of bits consisting of a bit arranged at the center of rotation (hereinafter referred to as "center bit") and a bit arranged around the center bit (hereinafter referred to as "peripheral bit"). Are configured to strike and drive at different times. This speeds up the bit hitting cycle compared to the conventional down-the-hole hammer that hits the ground by moving a single bit of approximately the same diameter as the drilling hole up and down, and instead hits the bit once. The impact on the ground generated by each hit is reduced, enabling excavation work with low vibration and low noise.

By the way, when the present inventors are operating a rotary excavator using the excavator 9, the excavator 9 may hit the central bit 91 and the peripheral bits 92 at the same time. There was found. According to the excavation device 9, even if such simultaneous impacts occur, it is possible to perform excavation work with lower vibration and lower noise than the down-the-hole hammer that has existed before the excavation device 9, but the present inventors can perform the excavation work. A prototype 93 with an improved excavator 9 was manufactured with the aim of further reducing vibration and noise.

In the prototype 93 shown in FIG. 18A, the central bit is abolished on the excavation surface, and the peripheral bit is provided with a corner portion 933 in which the striking surface 931 is extended in the direction of the rotation axis of the excavation device 9, and each peripheral bit is provided. The tip angle of the corner portion 933 of the bit is positioned at the rotation axis 9R, and the corner portions 933 are arranged so as to abut each other with a slight gap (hereinafter, the peripheral bits having such a configuration are referred to as “excavation bit 930”. "). In general, a plurality of cemented carbide chips that are convex with respect to the impact surface are planted on the impact surface of the excavation bit, and the chips are dispersedly arranged at predetermined intervals. The excavation bit 930 of the prototype also has a structure in which a tip 934 is planted in the same manner.

Japanese Unexamined Patent Publication No. 2007-92447

However, when the present inventor or the like performs excavation work using the rotary excavator 9 or the prototype 93 (collectively, the "rotary excavator 9 or the like"), it is composed of earth and sand, soft rock, or the like. If excavation work is performed on the ground that is expected to consist of a soft layer (hereinafter referred to as "soft layer") and an unexpected hard rock is hit, can the rotary excavator 9 or the like crush the hard rock due to insufficient striking force? Alternatively, there is a problem that it takes time to crush the hard rock, or the excavation direction deviates along the inclined surface of the hard rock because it cannot be crushed.

In such a case, the rotary excavator 9 and the like were once pulled out and replaced with a single-bit down-the-hole hammer with a large striking force to deal with it. It took extra effort and time. During the work with the single-bit down-the-hole hammer, large vibrations and noises were generated.

The present invention was devised in view of the above points, and can be applied to both soft layers and hard rocks without replacing the equipment, and the extra labor and time required for the replacement work can be omitted. In addition, it is an object of the present invention to provide an excavator and a rotary excavator capable of performing excavation work with relatively low noise and low vibration even when excavating hard rock.

In order to achieve the above object, the excavator of the present invention has a tubular casing that can rotate in the circumferential direction, a drive unit that is housed in the casing and can supply driving force, and around the rotation axis of the casing. It has a plurality of excavation bits that can move forward and backward along the axial direction of the casing by receiving the driving force, and the striking force that the excavating bit exerts by receiving the driving force differs for each excavation bit. , Or a group of excavation bits set in any aspect in which at least one excavation bit differs from the other excavation bits.

Here, since the excavation device of the present invention includes a tubular casing that can rotate in the axial direction, a drive unit can be stored inside and a group of excavation bits can be provided, and a rotational drive that can apply a rotational force. Can be used in combination with the device. As a result, it is possible to carry out an excavation method in which the excavation bit group rotates in the circumferential direction while applying a striking force to the excavated object (hereinafter referred to as “excavated object”) to be excavated. Further, since this excavation device includes the above-mentioned drive unit, a driving force can be supplied to the excavation bit group, and each excavation bit can move forward and backward.

Further, since this excavation device includes the above-mentioned excavation bit group, each excavation bit moves forward and backward in the axial direction of the casing in response to the driving force supplied from the drive unit, and the object to be excavated is moved by the striking surface. You can hit.

In addition, this group of excavation bits is arranged around the axis of rotation of the casing, and has a plurality of excavation bits that can move forward and backward along the axial direction of the casing by receiving a driving force, and the excavation bits are the driving force. All excavation bits are set so that the striking force exerted by receiving the excavation bit is different for each excavation bit, or at least one excavation bit is different from the other excavation bits. The striking force to be applied is not uniform, and the striking force can be different. As a result, for example, when a hard rock is hit during a rotary excavation operation, the excavation bit to which a larger impact force is applied than other excavation bits crushes the hard rock or cracks the hard rock at the first impact. Can be crushed into small pieces by the subsequent impact of other drilling bits.

For example, when trying to improve the striking force of all the excavation bits constituting the excavation bit group, it is necessary to take measures such as increasing the size of each part (piston, etc.) of the drive unit, which is exchanged for the improvement of the excavation force. In addition, there are problems such as an increase in the weight or size of the entire device and an increase in the consumption of a power source (working fluid, etc.). Therefore, it is possible to minimize the increase in the weight of the entire device and the increase in the energy consumption of the drive unit.

For example, as described above, when excavation work of the ground predicted to be composed of a soft layer is performed using a rotary excavator 9 or the like and an unexpected hard rock is hit, the rotary excavator 9 or the like strikes. There was a problem that the hard rock could not be crushed due to insufficient force, or it took time to crush the hard rock, or the excavation direction deviated along the slope of the hard rock without being able to crush. Since the devised excavator can deal with hard rock by the excavation bit group set in any of the above modes, it can deal with both soft layers and hard rock without changing the equipment. This makes it possible to save time and effort due to replacement of equipment. In addition, even when excavating hard rock, the excavation work can be performed with relatively low noise and low vibration.

Further, the excavation bit group is arranged in the first arrangement mode in which only one of the striking surfaces of one excavation bit in each excavation bit overlaps with the rotation axis, or the rotation axis of the striking surface of the excavation bit. A corner portion is formed on the center side, and only the edge portion on the rotation axis center side of a set of striking surfaces arranged to face each other across the rotation axis center overlaps with the rotation axis center, and the tip of the corner portion is the rotation axis. In the case of a configuration in which the edges on the rotation axis side of each striking surface are assembled so as to be close to each other in the vicinity of the rotation axis by any of the second arrangement modes arranged so as not to overlap the center. Each drilling bit is mounted in and near the axis of rotation with almost no gap. According to the configuration of this excavation bit group, the object to be excavated hit by the excavation bit group can be excavated evenly, and it is convex to the center of the back side of the hole excavated at the time of hard rock excavation (hereinafter referred to as "excavation hole"). It becomes substantially flat without forming an uncut portion (hereinafter referred to as "central convex portion").

This will be described in detail with reference to FIG. In the past, when the present inventor and others performed excavation work using the above-mentioned prototype 93, they accidentally hit a hard rock in the soil and pulled out the prototype 93 after the work. The convex portion H6 is formed (see FIG. 18C), and the vicinity of the corner portion 933 of each excavation bit 930 is worn away, and the central deformed portion H7 in a state where the striking surface 931 itself is also recessed is generated. (See FIG. 18 (b)). When the excavation work for the hard rock was retried at a later date, it was confirmed that the central convex portion H6 was formed and the central deformed portion H7 of the prototype 93 was generated.

The cause of the formation of the central convex portion H6 and the occurrence of the central deformed portion H7 is not always clear, but it is presumed that the cause is as follows.
(A) When the prototype 93 is in operation, each of the excavation bits 930 arranged at the excavation side end of the excavation device 9 individually moves forward and backward at different timings. That is, each excavation bit 930 in the retracted state and the advanced state is mixed, and as a result, the load applied to each excavated bit 930 (axial load due to its own weight, impact load due to impact) is not evenly distributed and is in the advanced state. Will concentrate on the digging bit 930 of
(B) Further, the edge of the striking surface 931 of the excavation bit 930 in the advanced state, or a portion close to the edge, is more likely to be worn away than other flat portions, and in particular, the corner portion 933 is tapered, so that it goes to the tip. The strength is weak. In addition, since the corners and their vicinity are tapered and have a smaller area than the other parts, if the chips 934 are arranged at the same density as the other parts, the number of chips 934 that can be planted is small.
(C) As described above, considering that the load is concentrated on the excavation bit 930 in the advanced state and the load is likely to be concentrated on the corner portion 933 among the excavation bits 930 in the advanced state, the load is planted in the corner portion 933. A small number of chips 934 are loaded with a larger load than the chips in other parts, which causes damage such as the chip 934 being worn out or the chip 934 falling off at an earlier stage than the other parts.
(D) Since the excavation force near the corner 933 is significantly reduced due to the breakage of the tip 934, the excavation force is different from that of the other part of the striking surface 931 and the base portion is directly inferior in strength to the tip 934. In the state of excavation, the corner 933 and its vicinity are worn or plastically deformed together with the base part, and the excavation force is further reduced.
(E) As a result, due to the difference in excavation force between the vicinity of the rotation axis 9R and other parts of the striking surface 931, the central convex portion H6 having a shape in which the central portion of the hole bottom surface H3 of the excavation hole H1 is raised from the outer periphery. Is formed,
(F) Further, a strong pressing force is generated at the end of the prototype 93 on the side to be excavated during the excavation work due to the weight of the own machine or the load from the outside of the machine, and under this pressing state, the central convex portion H6 On the other hand, it is probable that the prototype 93 continued to rotate while hitting the striking surface 931 near the corner portion 933, causing plastic deformation or uneven wear, and the central deformed portion H7 was generated on the striking surface 931. ..

However, according to the excavation apparatus of the present invention, the excavation bit group has an edge on the rotation axis side of each striking surface in the vicinity of the rotation axis according to either the first arrangement mode or the second arrangement mode described above. By arranging them so that they are close to each other, it is possible to perform excavation work with low vibration and low noise even for hard rock, and it is possible to suppress the formation of a central convex part in the center of the back side of the excavation hole. It is possible to suppress the deformation and uneven wear of the excavation bit caused by the formation of the central convex portion (hereinafter, may be referred to as "suppression of the occurrence of the central deformed portion").

That is, when the excavation bit group is configured in the first arrangement mode, only one of the striking surfaces is arranged so as to overlap the rotation axis (hereinafter referred to as "rotation axis overlapping arrangement"), so that the striking surface is It is possible to always overlap the rotation axis and its vicinity. According to this rotation axis overlapping arrangement, during the rotary excavation work, a part of the above-mentioned striking surface is excavated in a state where it always overlaps and passes through the rotary axis and its vicinity, so that the center of the excavated surface is excavated. It can be excavated at all times and the load concentration on the corners is eased. As a result, the formation of the central convex portion is suppressed even during the excavation of hard rock, and the occurrence of the central deformed portion is also suppressed accordingly.

When the excavation bit group is configured in the second arrangement mode, a corner portion is formed on the rotation axis side of the striking surface, and the rotation axis of a set of striking surfaces arranged opposite to each other with the rotation axis in between. Since only the side edge overlaps with the rotation axis and the tip of the corner does not overlap with the rotation axis, the tip of the corner of the excavation bit overlaps with the rotation axis during rotary excavation work. No arrangement (hereinafter referred to as "non-overlapping arrangement of the rotation axis on the striking surface"), passing the long edge instead of the tip of the corner intermittently or substantially continuously through the rotation axis and its vicinity. Can be made to. As a result, the center of the surface to be excavated is excavated at the edge of the pair of striking surfaces arranged opposite to each other on the rotation axis side and the striking surface along the same, and a plurality of loads concentrated on the striking surface are applied. It can be dispersed on (at least two) striking surfaces, and the load concentration on the corners is also alleviated. Is suppressed.

Further, in the first arrangement mode, the drive unit is an excavation bit in which the striking surface overlaps the rotation axis, or in the second arrangement mode, the striking surface is the rotation axis only at the side edge of the rotation axis. If any of the excavation bits arranged in an overlapping manner is set to give the maximum striking force among the excavation bits constituting the excavation bit group, the excavation bits are arranged overlapping in the rotation axis. The striking force of the excavated bit is particularly enhanced. For example, if a hard rock is hit during a rotary excavation operation, the drilling bit with the maximum impact force will either crush the hard rock or crack the hard rock with the first impact, followed by another drilling bit. It can be crushed into small pieces by the impact of the above, which can further enhance the effects of suppressing the formation of the central convex portion and suppressing the generation of the central deformed portion during hard rock excavation.

Similar to the excavation bit group set in either the first striking mode or the second striking mode described above, the present invention also applies a striking force to at least one of the excavation bits constituting the excavation bit group. Since the configuration is improved, it is possible to minimize the increase in the weight of the entire device and the increase in the consumption of the driving fluid.

Further, when the excavation bit has a ridge striking portion protruding from the striking surface formed along the peripheral edge of the casing of the striking surface, the ridge striking portion is the first to be excavated. Since the impact can be applied, even if the object to be excavated is the hard rock in the excavation hole, the hard rock is crushed by this impact, or the hard rock is cracked by the first impact. It can be crushed into small pieces by hitting with other parts of the hitting surface that follows.

Each of the above-mentioned excavation bits has one striking surface on the excavated side, but the striking surface is not limited to only one flat surface, for example, a surface to be excavated. It may be a stepped structure composed of a plurality of surfaces, a mode including a plurality of different inclined surfaces, or the like. Further, the excavation bit on which the ridge striking portion is formed is at least one or more of the excavation bits constituting the excavation bit group, and the ridge striking portion is formed on all the excavation bits constituting the excavation bit group. Of course, it also includes. Each excavation bit may also have an excavation portion (for example, a portion for excavating the inner side wall of the hole) on the side surface, but the excavation portion on the side surface does not correspond to the above-mentioned striking surface.

Further, the drive unit has a plurality of cylinders and a piston built in each cylinder and actuated by a working fluid to apply a striking force to the excavation bit, and the weight of at least one piston is the weight of the other piston. If they are set to be different, the piston in the cylinder is operated by the working fluid flowing from the outside, and the excavation bit can be driven by the striking force of the piston. Further, since the drive unit is operated by the working fluid and has a relatively simple structure having a cylinder and a piston, the efficiency of the manufacturing process and maintenance can be improved.

In addition, when the pipe diameter of the cylinder containing the maximum weight of each piston is set to the maximum among each cylinder, the appearance is glimpsed as compared with the case where all the cylinders have the same diameter. For example, the cylinder containing the heaviest piston can be identified. As a result, for example, when the cylinder with the maximum weight piston is arranged for the excavation bit having the maximum striking surface portion, the weight of each cylinder or the like is not confirmed from the outside. Since the cylinder containing at least the maximum weight of the piston can be visually recognized, the efficiency of work can be improved in the manufacturing or assembling process and maintenance.

For example, when increasing the weight of the piston in order to increase the striking force applied by the excavation bit, if the piston is made of a material with the same specific gravity and the cylinder diameter and length are uniform, the weight will increase. Along with this, the length of the piston is extended, the moving distance in the cylinder is shorter than that of a lightweight piston, and there is a possibility that a sufficient striking force cannot be exerted compared to the weight of the piston. However, by setting the pipe diameter of the cylinder to be large, even if the piston with the maximum weight is built in, the height of each piston can be made uniform (or substantially uniform), thereby moving in the cylinder. The distance is the same as (or almost the same as) a lightweight piston, and the striking force can be fully exerted.

Further, when the pipe diameter of the other cylinder is set in the range of 100% to 50% with respect to the one having the largest pipe diameter among the cylinders, the area of the striking surface of each excavation bit is different. Can be suitably used for.

For example, when a cylinder with a small pipe diameter is applied to an excavation bit having a large striking surface area, the range of striking force transmitted from the cylinder is narrow, and the striking force applied by the striking surface may decrease. By applying a cylinder with a large pipe diameter to a drilling bit with a large area, the striking force is transmitted to a wider range of the striking surface of the drilling bit than when a cylinder with a small pipe diameter is applied, thus improving the power. Can be made to.

If the above-mentioned "tube diameter of another cylinder" is less than 50% of the cylinder having the maximum pipe diameter, the weight balance between the cylinder and the cylinder having the maximum weight is significantly deteriorated, which is not preferable.

For example, if the drilling rig is on the ground, the rotation balance will be poor and more counterweights will be required to correct this, resulting in increased manufacturing costs, increased maintenance effort, and an increase in overall weight. There is a disadvantage of increased energy consumption. In addition, if there is an extreme difference in the striking force applied from the striking surface due to the pipe diameter of the cylinder, the excavated surface on the excavated side becomes uneven, and slippage occurs especially when hitting hard rock. It may occur and the excavation direction may shift. For this reason, it is preferable that the above-mentioned "tube diameter of another cylinder" is 50% or more of the cylinder having the maximum pipe diameter.

Further, when the weight of the other piston is set in the range of 100% to 20% with respect to the maximum weight of each piston, the striking force applied based on the weight ratio of the piston is also different. This means that, for example, if a hard rock is hit during a rotary drilling operation, the heaviest drilling bit will either crush the hard rock or crack the hard rock on the first blow, followed by other. It can be crushed into small pieces by hitting a drilling bit.

Among a plurality of pistons, one or more pistons having the same weight as the maximum weight piston (100%) may be present, and all pistons other than the maximum weight piston have a light weight (99% to 20%). You may. If the above-mentioned "weight of another piston" is less than 20% of the maximum weight piston, the balance between the piston and the maximum weight piston is significantly deteriorated, which is not preferable.

For example, if the drilling rig is on the ground, the rotation balance will be poor and more counterweights will be required to correct this, resulting in increased manufacturing costs, increased maintenance effort, and an increase in overall weight. There is a disadvantage of increased energy consumption. In addition, if there is an extreme difference in the striking force generated from the piston, the excavated surface on the excavated side becomes uneven, and slippage may occur especially when hitting hard rock, which may cause a deviation in the excavation direction. .. For this reason, it is preferable that the above-mentioned "weight of another piston" is 20% or more of the maximum weight of the piston.

Further, when a storage tank connected to the side opposite to the excavation bit group of the casing and capable of storing the working fluid is provided, the working fluid introduced from the outside can be temporarily stored and supplied to the drive unit, for example. When the working fluid is compressed air (hereinafter referred to as "air"), the air can be temporarily stored in a high pressure state.

Further, when the storage tank has a working fluid distribution unit that appropriately distributes the working fluid so that the timing of supplying the driving force to the excavation bit by the drive unit is different, the operation to the drive unit is performed by the working fluid distribution unit. When the fluid supply timing can be changed, for example, when the drive unit has a structure having a plurality of cylinders and a piston built in each cylinder and actuated by the working fluid to apply a striking force to the excavation bit. Can change the operating timing of the piston for each cylinder.

In order to achieve the above object, the rotary excavator of the present invention has a tubular casing that can rotate in the circumferential direction, a drive unit that is housed in the casing and can supply driving force, and a rotation axis of the casing. It includes a plurality of excavation bits that are arranged around the excavation bit and can move forward and backward along the axial direction of the casing by receiving the driving force, and the striking force that the excavating bit exerts by receiving the driving force differs for each excavation bit. Alternatively, it comprises an excavator having an excavation bit group set in any aspect in which at least one excavation bit differs from the other excavation bits, and a rotary drive device that imparts a rotational force to the excavator.

Here, in the rotary excavator of the present invention, since the excavator has a cylindrical casing that can rotate in the axial direction, a drive unit can be stored inside and a group of excavating bits can be provided, and the rotary drive device can be provided. In combination with, rotational force is given. This makes it possible to carry out an excavation method in which the excavation bit group rotates in the circumferential direction while applying a striking force to the object to be excavated.

Further, in the rotary excavator of the present invention, since the excavator has the above-mentioned drive unit, a driving force can be supplied to the excavation bit group, and each excavation bit can move forward and backward. In addition, since the excavator has the above-mentioned excavation bit group, each excavation bit moves forward and backward in the axial direction of the casing in response to the driving force supplied from the drive unit, and hits the object to be excavated by the striking surface. can do.

In addition, in the rotary excavator of the present invention, the striking force exerted by the excavator under the driving force of the excavating bit differs from excavating bit to excavating bit, or at least one excavating bit is another excavating bit. By having the excavation bit group set in any of the modes different from the above, the striking force applied by all the excavation bits is not uniform, and the striking force can be different. As a result, for example, when a hard rock is hit during a rotary excavation operation, the excavation bit to which a larger impact force is applied than other excavation bits crushes the hard rock or cracks the hard rock at the first impact. Can be crushed into small pieces by the subsequent impact of other drilling bits.

Further, since the rotary excavator of the present invention includes the above-mentioned rotary drive device, the excavator can be rotated in combination with the rotary drive device, whereby the excavation bit group is rotated in the circumferential direction to be excavated. It is possible to carry out an excavation method in which a striking force is applied to an object.

Then, according to the rotary excavator of the present invention, the striking force exerted by the excavator bit by receiving the driving force differs for each excavation bit as compared with the case where the above-mentioned rotary excavator 9 or the like is used. Or, because at least one drilling bit is different from the other drilling bits, the hard rock can be dealt with by a group of drilling bits set in any aspect, so that the soft layer and the hard rock are not replaced. It can handle any of the rocks, which saves the extra effort and time of exchanging equipment. In addition, even when excavating hard rock, the excavation work can be performed with relatively low noise and low vibration. Further, according to the rotary excavator of the present invention, an excavator having an improved striking force to the extent that it can deal with hard rock is provided as compared with the case where the above-mentioned rotary excavator 9 or the like is used. However, it is possible to minimize the increase in the weight of the entire device and the increase in the energy consumption of the drive unit.

According to the excavator and the rotary excavator of the present invention, it is possible to handle both soft layers and hard rocks without replacing the equipment, and it is possible to save the extra labor and time required for the replacement work. In addition, excavation work can be performed with relatively low noise and low vibration even when excavating hard rock.

It is a front view which shows the rotary excavator of this invention. It is a perspective view which shows the excavation apparatus (first embodiment) of the rotary excavator shown in FIG. The structure of the excavator shown in FIG. 2 is shown. FIG. 2A is an explanatory view showing an attachment / detachment structure to and from an air tank, and FIG. 2B is an explanatory view showing an attachment / detachment structure to an air tank and an attachment. It is a perspective explanatory view which shows by disassembling the component part of the excavation apparatus shown in FIG. It is a side view enlarged explanatory view of the middle part to the tip part of the excavation apparatus shown in FIG. The vertical cross section of the excavator shown in FIG. 2 is shown, and it is explanatory drawing which showed the flow of the air in an air tank, and the movement of a piston and an excavation bit. The excavation bit group (second arrangement mode) of the excavation device shown in FIG. 2 is shown, and each piston member (a member having a cylinder and a piston; hereinafter used in the same meaning) arranged for each excavation bit is drawn by an imaginary line. It is the bottom view explanatory view shown. The excavation bit 6B1 (6B2) of the excavator shown in FIG. 7 is shown. FIG. 7A is a perspective view 1 seen from the bottom surface side, FIG. 7B is a bottom view, and FIG. , (D) is a side view explanatory view. It is a perspective view of the air flow control member. It is explanatory drawing of the use state of the excavation apparatus shown in FIG. Omits the excavator and the middle part of the excavation hole, and shows the process of discharging soil from the bottom of the hole to the mouth of the hole. It is a perspective view which shows the other excavation apparatus (second embodiment) of this invention. The excavation bit group (first arrangement mode) of the excavation apparatus shown in FIG. 11 is shown, and is a bottom view explanatory view showing each piston member arranged for each excavation bit with an imaginary line. It is a modification of the excavation bit group of the present invention, in which (a) does not apply the second arrangement mode to the excavation bit group shown in FIG. 7, and the tip corner portion of each excavation bit is non-overlapping arrangement on the rotation axis. It is a bottom view explanatory view of the modification 1, and (b) is a modification in which the first arrangement mode is not applied to the excavation bit group shown in FIG. It is a bottom view explanatory view of Example 2. It is a modification of the excavation bit group of the present invention, (a) is a bottom view explanatory view of modification 3, which is a mode in which a ridge striking portion is not formed on the excavation bit shown in FIG. 7, and FIG. 12 (b) is a modification. It is the bottom view explanatory view of the modification 4 which is the aspect which does not form the ridge striking part in the excavation bit shown in (c), and (c) has two excavation bits constituting the excavation bit group, and the piercing bit hits the excavation bit. It is a bottom view explanatory view of the modification 5 which is the aspect which does not form a portion. A modification of the excavation bit of the present invention, (a) is an excavation bit (deformation example) in which two openings on the striking surface are formed and two exhaust guide grooves extending from each opening are formed in parallel. 6) is a bottom view, and (b) is an excavation bit (deformation) in which two openings on the striking surface are formed, and two exhaust guide grooves extending from each opening are formed in opposite directions. It is a bottom view of Example 7). It is a modification of the excavator of the present invention, (a) is a side view of the modification 8 in which spiral blades are provided in the longitudinal direction of the outer periphery of the body of the excavator, and (b) is a modification of the excavator. It is a side view of the modification 9 which is the aspect which provided the flat bar extending in the longitudinal direction of the outer periphery of the body | body. It is a perspective view which shows the prior art of the excavation apparatus described in Patent Document 1. FIG. (A) is a perspective view showing a prototype of the excavator before the present invention, (b) is an explanatory view comparing the excavation bits before and after the excavation work of the prototype shown in (a), and (c) is in (a). It is explanatory drawing which shows the inside of the excavation hole excavated by the prototype shown.

Embodiments of the present invention will be described in more detail with reference to FIGS. 1 to 16. The following explanation is
[First Embodiment] (Excavator 2a in which the excavation bit group is the second arrangement mode),
[Second Embodiment] (Excavator 2b in which the excavation bit group is the first arrangement mode),
[Modification 1]-[Modification 9],
It is done in the order of. In addition, the reference numerals in the drawings are attached within a range that reduces complexity and facilitates understanding, and a plurality of equivalents having the same reference numerals may be assigned only a part thereof. .. And, in each embodiment and each modification described later, air is adopted as a working fluid, but the present invention is not limited to this, and for example, various gases, other fluids such as liquids such as water and oil can be used. It is not an exclusion.

[First Embodiment]
The rotary excavator 1 shown in FIG. 1 includes an excavator 2a and a rotary drive device 8 capable of imparting a rotational motion to the excavator 2a. Each part will be described in detail below. And the excavation method performed using the rotary excavator 1 is
(First step) An excavator 2a having an excavation bit group 5a composed of a plurality of excavation bits and a rotary excavator 1 composed of a rotary drive device 8 are assembled and installed on the object H to be excavated.
(Second step) While rotating the excavation device 2a by the rotary drive device 8 installed in the first step, each excavation bit of the excavation device 2a is moved forward and backward, and the object H to be excavated is hit by the striking surface 65d. Excavate the object to be excavated H,
It is done by.

According to this excavation method, the rotary excavator 1 rotates the excavation device 2a by the rotary drive device 8, and the excavation bit group 5a applies a striking force to the object to be excavated H while rotating in the circumferential direction. It can be carried out (see FIG. 1). Further, according to this excavation method, since the hard rock H4 can be dealt with by the ridge striking portion 655 as compared with the case where the above-mentioned rotary excavator 9 or the like is used, it is soft without changing the equipment. It is possible to deal with both the layer H5 and the hard rock H4 (see FIG. 10), which saves extra labor and time due to the replacement of equipment. In addition, even when excavating hard rock, the excavation work can be performed with relatively low noise and low vibration.

(Excavator 2a)
See FIGS. 1 to 10. The excavation device 2a includes a casing 3, a drive unit 4 housed in the casing 3, and a plurality of excavation bits 6A1, 6A2, 6B1, and 6B2 (hereinafter, referred to as “6A1 to 6B2” in all of these descriptions). The drilling bit group 5a, which is the configured second arrangement mode 52, is provided. In the excavation device 2a, the air tank 7 (corresponding to the storage tank described above) is continuously provided at a position opposite to the excavation bit group 5a of the casing 3.

<Casing 3>
The casing 3 is formed so as to be rotatable in the axial circumferential direction of the rotation axis 3R, and the drive unit 4 can be housed therein and the excavation bit group 5a can be provided. By rotating the entire excavation bit group 5a, it is possible to carry out an excavation method in which the excavation bit group 5a applies a striking force to the excavated object H (the ground in the present embodiment) while rotating in the circumferential direction 3C (FIG. 1). reference).

In the present embodiment, the casing 3 is a hollow cylindrical body, and the air tank side lid 33 is attached to and detached from the air tank 7 side of the casing 3, and the excavated side lid 34 is attached to and detached from the excavated side of the casing 3. It is installed as possible. The air tank side lid 33 and the object side lid 34 have a required thickness, and insertion holes 331 and 341 for inserting and inserting each end of the piston member 41 are formed (FIGS. 4 and 4). 6).

The insertion hole 331 of the air tank side lid 33 communicates with a ventilation hole (not shown) on one end side of the piston member 41 to be fitted. The insertion hole 341 of the lid 34 on the side to be excavated communicates with the ventilation hole (reference numeral omitted) on the other end side of the piston member 41 to be fitted (see FIGS. 4 and 6).

A removable chuck guide 35 and a drive chuck 36 are attached to the outer surface (bottom surface in FIG. 4) of the object side lid 34 to be excavated. The excavation bit group 5a is attached to the side to be excavated of the casing 3 via the chuck guide 35 and the drive chuck 36 (see FIGS. 4 and 6).

The chuck guide 35 is attached to the casing 3 by using a fastener composed of a bolt 370 and a nut 371. The chuck guide 35 has a substantially circular shape in a plan view in which a notch is formed on the side to be excavated, has a predetermined thickness, and has a plurality of through holes 351 (excavation bits 6A1 to 6B2) into which the excavation bits 6A1 to 6B2 can be inserted. (4 in total in this embodiment) are formed at substantially equal intervals in the circumferential direction (see FIGS. 4 and 6).

The drive chuck 36 is a cylindrical body, and is sandwiched and attached between the chuck guide 35 and the casing 3. Then, the drive chuck 36 is attached so that one end side in the longitudinal direction fits into the insertion hole 341 of the excavated side lid 34 and the other end side in the longitudinal direction fits into the through hole 351 of the chuck guide 35 (FIGS. 4 and 4). 6). The drive chuck 36 has a hexagonal inner diameter at least near the other end in the longitudinal direction (not shown), and has a size that allows the connection shaft portions 61 of the excavation bits 6A1 to 6B2 to be described later to be inserted. It is set.

Further, the casing 3 is provided with a screw portion 32 in a region intermediate in the longitudinal direction on the outer surface 31 of the body portion (see FIGS. 3, 5 and the like). According to the screw portion 32, the crushed rock or earth and sand (slime) generated during the excavation work is more efficiently sent out toward the hole H2 of the excavation hole (for example, in the case of a vertical hole, in the direction of the ground surface). (Hereinafter referred to as "excretion") can be performed (see FIG. 10 (c)).

The area of the screw portion 32 described above is set to be smaller than both ends (upper or lower in FIG. 5) in the longitudinal direction of the outer surface 31 of the body portion, and the spiral blade provided in this small diameter portion. It is composed of 321 and a reinforcing rib 322 that intersects with the spiral blade 321 and extends in the longitudinal direction of the outer surface 31 of the body. Further, the spiral blades 321 and the reinforcing ribs 322 are set so that the positions of the protruding tips in the outer peripheral direction are substantially the same as the virtual surface 3V connecting both ends of the body outer surface 31 in the longitudinal direction. Then, the spiral blades 321 are formed with engaging recesses 324 at equal intervals in the circumferential direction.

Since the screw portion 32 is set to this protruding height, soil can be discharged without expanding the excavation hole H1 from the initially set value during the excavation work. Further, since the screw portion 32 does not protrude from the upper portion or the lower portion of the outer surface 31 of the body portion, for example, when the excavator 2a is laid down and transported, the tip of the spiral blade 321 may be damaged. Can be suppressed. Further, since the screw portion 32 has the reinforcing rib 322, it is possible to suppress the possibility of deformation of the spiral blade 321 due to an external force applied from the plate thickness direction of the spiral blade 321.

<Drive unit 4>
FIG. 1, FIG. 4 and FIG. 6 are mainly referred to. The drive unit 4 is housed in the casing 3 and can supply a driving force to the excavation bit group 5a to move the excavation bits 6A1 to 6B2 forward and backward.

In the present embodiment, the drive unit 4 is composed of four piston members 41 housed in the casing 3. In addition to the piston 411, each piston member 41 includes a cylinder 412, a check valve (code omitted), an air distributor (code omitted), a valve spring (code omitted), a make-up ring (code omitted), and an O-ring (code omitted). , Piston retired ring (code omitted), bit retainer ring (code omitted), etc., and has almost the same structure as a known down-the-hole hammer drive mechanism (for example, described in JP-A-61-92288). .. Then, each piston member 41 is fixed in the casing 3 in a state of being sandwiched between the above-mentioned excavated object side lid 34 and the chuck guide 35.

The operation of the drive unit 4 will be briefly described. The air that has flowed into the piston member 41 from the air tank 7 first passes through the side surface of the piston 411 and turns to the excavation bits 6A1 to 6B2, whereby the piston 411 moves to the air tank 7 side. Next, as the piston 411 moves, air turns to the air tank 7 side of the piston 411, and air flows from the opening 611 of the connection shaft 61 of the excavation bits 6A1 to 6B2, which will be described later, to the opening 653 of the striking surface 65. The piston 411 moves from the air tank 7 side to the excavation bits 6A1 to 6B2 side. By repeating this operation, the piston 411 moves forward and backward, and when the piston 411 moves to the excavation bits 6A1 to 6B2, an impact force (corresponding to the above-mentioned driving force) is applied to the excavation bit 6, and the impact force causes the excavation bit. 6A1 to 6B2 are driven.

Further, in the drive unit 4, the inflow timing of the air E is adjusted by the air flow control member 73 (corresponding to the above-mentioned "working fluid distribution unit") provided in the air tank 7 described later, and the pistons 411 are respectively. It is set to move forward and backward at different timings.

Furthermore, the drive unit 4 is set so that the piston members 41 have different diameters and the weight of the built-in piston 411 is different (see FIG. 7). Specifically, in the present embodiment, the piston 411 of the piston member 41 connected to one excavation bit 6A1 to be described later has a diameter of 10 inches (254 mm) and a weight of 46 kg in the clockwise circumferential direction. The piston 411 of the piston member 41 connected to one excavation bit 6B1 adjacent to the excavation bit 6A1 has a diameter of 6 inches (152.4 mm) and a weight of 23 kg, and is adjacent to the excavation bit 6B1 (that is, one). The piston 411 of the piston member 41 connected to the other excavation bit 6A2 (opposed to the excavation bit 6A1) has a diameter of 8 inches (203.8 mm) and a weight of 31 kg and is adjacent to the excavation bit 6A2. The piston 411 of the piston member 41 connected to the other excavation bit 6B2 (ie, opposite one of the excavation bits 6B1) is set to have a diameter of 5 inches (127 mm) and a weight of 9.4 kg.

In this way, among the excavation bits 6A1 to 6B2 constituting the excavation bit group 5a, the maximum striking force generated by the maximum piston 411 is given to the maximum striking surface (the striking surface 65a of the excavation bit 6A1). During rotary excavation work, the excavation bit 6A1 to which the maximum impact force is applied crushes the hard rock H4 or cracks the hard rock H4 and is subsequently hit by other excavation bits 6A2, 6B1 and 6B2. It can be crushed into small pieces, which suppresses the formation of the central convex part H6 and central deformation during hard rock excavation, while minimizing the increase in the weight of the entire device and the increase in the consumption of working fluid (air). Each effect of suppressing the generation of the part H7 can be further enhanced.

<Excavation bit, excavation bit group>
See FIGS. 5 and 7. The excavation bit group 5a is provided on the object to be excavated side of the casing 3 and is composed of four excavation bits 6A1 to 6B2 that can move forward and backward in the axial direction of the casing 3 by receiving a driving force, and each of the excavation bits 6A1 to 6B2. The striking surface 65 is arranged around the rotation axis 3R of the casing 3.

The excavation bit group 5a is provided on the casing 3, and a plurality of excavation bits 6A1 to 6B2 in which the ridge striking portion 655 protruding from the striking surface 65 in the striking direction is formed along the peripheral edge portion of the casing 3 are excavated. It is configured so that the first hit can be applied to the object H by the ridge hitting portion 655. As a result, even if the object to be excavated is the hard rock H4 in the excavation hole H1, the hard rock H4 is crushed by this impact, or the hard rock H4 is cracked by the first impact. It can be crushed into small pieces by subsequent hits by other parts of the hitting surface. That is, since it is possible to deal with not only the soft layer H5 but also the hard rock H4, it is possible to deal with both the soft layer H5 and the hard rock H4 without changing the equipment. It is possible to save time and effort. In addition, even when excavating hard rock, the excavation work can be performed with relatively low noise and low vibration.

In addition, in the excavation bit group 5a, corner portions 67 are formed on the excavation bits 6A1 to 6B2 constituting the excavation bit group 5a on the rotation axis 3R side of each striking surface 65. In the excavation bit group 5a, only the edge portion 661 on the rotation axis 3R side of a set of striking surfaces 65 (striking surfaces of the excavation bits 6A1 and 6A2) arranged to face each other with the rotation axis 3R in between is the rotation axis. In the second arrangement mode 51 in which the tip of the corner portion 67 overlaps with the 3R and is arranged so as not to overlap with the rotation axis 3R, the edge of each striking surface 65 on the rotation axis 3R side is the rotation axis 3R. They are assembled so as to be close to each other in the vicinity of (see FIG. 7). Each striking surface 65 is located at 6C on a substantially orthogonal plane of the rotation axis 3R of the casing 3 (see FIG. 5), and can impact the object to be excavated H.

In the excavation bit group 5a, the striking surfaces 65 of the excavation bits 6A1 to 6B2 are arranged around the rotation axis 3R of the casing 3, and the rotation axis 3R side of each striking surface 65 is arranged according to the second arrangement mode 51 described above. Since the edges of the excavation bits 6A1 to 6B2 are assembled so as to be close to each other in the vicinity of the rotation axis 3R, the excavation bits 6A1 to 6B2 are attached to the rotation axis 3R and its vicinity with almost no gap. According to the configuration of the excavation bit group 5a, the excavated object H hit by the excavation bit group 5a can be excavated evenly, and the excavation hole H1 formed by the excavation work has a central convex portion formed on the inner bottom. It becomes almost flat without being done.

Since the excavation bit group 5a is configured in the second arrangement mode 51, the corner portion 67 is arranged so that the rotation axis does not overlap with the striking surface 65 in the direction of the rotation axis during the rotary excavation work. An edge portion 611 longer than the tip can pass the rotation axis 3R and its vicinity intermittently or substantially continuously. As a result, the center of the excavated surface is excavated at the edge portion 661 on the rotation axis side of the striking surface 65 of the excavation bits 6A1 and 6A2 arranged opposite to each other and the striking surface 65 of the portion along the rotation axis side. Therefore, the load concentrated on the striking surface 65 can be distributed by the plurality of striking surfaces 65 (two in the present embodiment), and the load concentration on the corner portion 67 is also alleviated. The formation of the central convex portion H6 is suppressed, and the generation of the central deformed portion H7 is also suppressed accordingly.

Specifically, in this excavation bit group 5a, a set (two) excavation bits 6A1 and 6A2 having the same shape and a set (two) excavation bits 6B1 and 6B2 (four in total) having the same shape are cross-shaped. It is configured in combination with. Here, the excavation bits 6A1 and 6A2 are arranged so as to face each other with the rotation axis 3R interposed therebetween, and the excavation bits 6B1 and 6B2 have the rotation axis 3R located between the excavation bits 6A1 and 6A2 in the circumferential direction. They are arranged opposite to each other.

The excavation bits 6A1 and 6A2 and the excavation bits 6B1 and 6B2 are different in shape and size of the striking surface and the like as will be described later (the excavation bits 6B1 and 6B2 are set smaller than the excavation bits 6A1 and 6A2). As a result, in the second arrangement mode 51, only the side portions 66 of the excavation bits 6A1 and 6A2 are arranged close to the rotation axis 3R, and the excavation bits 6B1 and 6B2 are arranged close to each other. , Neither the side portion 66 nor the corner portion 67 is arranged close to the rotation axis 3R (in other words, is arranged apart from the rotation axis 3R). Further, the corners 67 of the excavation bits 6A1 and 6A2 and the excavation bits 6B1 and 6B2 are located at about 6% of the distance from the rotation axis 3R to the outer peripheral end of the casing 3 with reference to the rotation axis 3R of the casing 3. Is located in.

Refer to FIGS. 8 and 10. The excavation bit 6A1 (same shape as 6A2) in the present embodiment is provided with a connecting shaft portion 61 that receives a driving force supplied from the driving unit 4 and a striking surface 65 on the side opposite to the connecting shaft portion 61, and each side thereof. The striking surface 65 surrounded by the portion 66 has a corner portion 67 at a position on the rotation axis 3R side when attached to the excavator 2a, and both edges sandwiching the corner portion 67 have different lengths. It is provided with a head portion 62 which is set so that the tip of the corner portion 67 does not overlap with the rotation axis 3R in the attached state (see FIG. 8). An air flow path 621 from the opening 611 of the connecting shaft portion 61 to the opening 653 of the striking surface 65 is formed in the excavation bit 6A1 (see FIG. 10).

The connecting shaft portion 61 is a means for connecting to the piston 411, is a free end having a cylindrical shape and an opening 611 formed at the tip thereof, and has a base end joined to the head portion 62, and is inside the drive chuck 36 described above. It is formed with an outer diameter that can be inserted into. In addition, the connection shaft portion 61 has a region on the head portion 62 side from the middle of the outer peripheral surface in the axial direction formed in a hexagonal cross-sectional view, and when the connection shaft portion 61 is inserted into the drive chuck 36, the portion is used as a spline shaft. In addition to demonstrating the function of, it is possible to prevent rotation in the circumferential direction and guide the advancing / retreating operation in the advancing / retreating direction. Further, the above-mentioned air flow path 621 in the connecting shaft portion 61 is provided with a check valve (not shown) capable of preventing a backflow of air flowing in the direction of the head portion 62. The connecting shaft portion 61 is mounted by the hammer bit retina ring and the O-ring described above so as not to come off from the drive chuck side.

The head portion 62 of the excavation bit 6A1 has a substantially pentagonal columnar shape, and has a joint portion 622 that joins with the base end of the connection shaft portion 61 and a second portion that connects with the joint portion 622 and extends toward the opposite side of the connection shaft portion 61. 1 side wall surface 623a, 2nd side wall surface 623b, 3rd side wall surface 623c, 4th side wall surface 623d and 5th side wall surface 623e (hereinafter, referred to as "623a to e" in all of these descriptions), side wall portion 623a It is composed of a striking surface 65 which is connected to ~ e and has a substantially pentagonal surface shape. Then, in the excavation bit 6A1, button-shaped cemented carbide tips 651 are formed at predetermined intervals on the entire striking surface 65 and a part of the side wall portion 623 (only the portion of the first side wall surface 623a described later near the striking surface). It is planted (distributed arrangement).

The excavation bit 6A1 has an arcuate end face shape arranged along a part of the outer surface 31 of the body of the casing 3 in the state of attachment to the chuck guide 35 (hereinafter, simply referred to as “attachment state” in this paragraph). 1st side wall surface 623a and one side edge of the 1st side wall surface 623a (“side edge” is used to mean excluding the joint portion 622 side and the striking surface 65 side, and the same shall apply hereinafter in this paragraph). Then, in the attached state, the second side wall surface 623b and the first side wall surface 623a extending toward the rotation axis 3R side of the casing 3 (hereinafter, simply referred to as “rotation axis side” in this paragraph). The third side wall surface 623c, which is connected to another side edge and extends toward the rotation axis 3R side in the attached state, and the first side wall surface 623a of the second side wall surface 623b are connected to the opposite side edge. The fourth side wall surface 623d extending on the rotation axis 3R side and in the horizontal major axis direction of the head portion 62 is connected to the end opposite to the first side wall surface 623a of the third side wall surface 623c, and the casing 3 is connected. It is extended toward the horizontal major axis direction of the rotation axis 3R side and the head portion 62, and is connected to the end opposite to the second side wall surface 623b of the fourth side wall surface 623d to form a sharp corner portion 67. It is composed of a fifth side wall surface 623e which is longer in the horizontal major axis direction than the fourth side wall surface 623d. That is, the striking surface 65 has a configuration in which the lengths of the side portions corresponding to the fourth side wall surface 623d and the fifth side wall surface 623e are different (unequal sides).

The striking surface 65 of the excavation bit 6A1 is a substantially flat flat striking portion 652 and the striking surface of the excavation bits 6A1 to 6B2 along the edge along the outer peripheral edge of the excavation bit group 5a in the direction of the rotation axis. (Along the peripheral portion of the casing 3 of 65), it is composed of a ridge striking portion 655 formed in an arc shape (see FIG. 8).

An opening 653 is formed substantially in the center of the flat striking portion 652, and air that has passed through the air flow path 621 formed in the excavation bit 6A1 is discharged from the opening 653. Further, the opening 653 is formed with two exhaust guide grooves 654 extending from the mouth edge of the opening 653 toward the second side wall surface 623b and the third side wall surface 623c. The exhaust guide groove 654 guides the air discharged from the opening 653 in the excavation hole H1 toward the outer surface 31 of the body of the casing 3 with the hole bottom surface H3, and efficiently diffuses the air in the hole. (See FIG. 10 (c)).

The ridge striking portion 655 has an inclined surface 656 formed between the ridge striking portion 652 and the flat striking portion 652, and the inclined surface 656 has a reverse taper shape having an inclination angle 65A from the flat striking portion 652 toward the ridge striking portion 655 of 35 °. The protruding height 65H of the ridge striking portion 656 is set to 3 cm from the flat striking portion 652 (see FIG. 8D). According to the ridge striking portion 656 of this configuration, the above-mentioned action and effect are exhibited, and at the same time, it is hard to be chipped and exhibits excellent durability.

Up to this point, the excavation bit 6A1 has been mainly described with reference to FIG. 8, but as described above, since the excavation bit 6A2 has the same structure as the excavation bit 6A1, it has the same effect and effect, and thus the description thereof will be omitted.

The excavation bits 6B1 and 6B2 have the same configuration as the excavation bit 6A1 for the side wall surfaces corresponding to the first side wall surface, the second side wall surface, and the third side wall surface, but the fourth side wall surface and the fifth side wall surface have the same configuration. The width of the side wall surface corresponding to the side wall surface is the same, and the striking surface 65 differs from the excavation bit 6A1 in that the side portions corresponding to the fourth side wall surface and the fifth side wall surface are equal sides. Further, since the excavation bits 6B1 and 6B2 have substantially the same basic configuration as the excavation bit 6A1 except for the above-mentioned points and sizes, individual illustrations and description of the structure and action / effect will be omitted.

By adopting the excavation bits 6A1 to 6B2 as described above, the striking surfaces 65 of the excavation bits 6A1 to 6B2 on which the ridge striking portion 655 is formed are arranged so that there is almost no gap in the rotation axis 3R of the casing 3. The excavation bit group 5a can be arranged, and the excavation bit group 5a can be arranged in the second arrangement mode 51, which is the above-mentioned non-overlapping arrangement of the rotation axes with respect to the striking surface.

(Air tank)
2, FIG. 3, FIG. 5, FIG. 6, FIG. 9, and FIG. 10 are mainly referred to. In the present embodiment, the drilling device 2a is provided with an air tank 7 for storing the working fluid (air) supplied to the drive unit 4. The air tank 7 can temporarily store the air introduced from the outside and supply it to the drive unit 4.

In the present embodiment, the air tank 7 is continuously provided on the side opposite to the excavation portion side of the casing 3 (that is, the side where the excavation bit group 5a is located). The air tank 7 is provided on a covered cylindrical body 70 having a diameter smaller than that of the casing 3 and airtightly, a connecting joint 71 provided on one end side of the body 70, and the other end side of the body 70. It has a connected body 72 and an air flow control member 73 provided in the body 70. Further, a cylindrical attachment 74 is externally fitted and attached to the air tank 7, and the attachment 74 has a structure that can be attached to and detached from the air tank 7 (see FIG. 3B).

Since the body portion 70 has a smaller diameter than the casing 3, the maximum diameter portion 74M of the attachment and the maximum diameter portion 3M of the casing are the same when the attachment 74 is attached, or the attachment 74 has a slightly smaller diameter (the diameter of the attachment 74 is slightly smaller. Hereinafter, it is set to be "substantially the same") (see FIG. 5), whereby the hole diameter of the excavation hole H1 is larger than the initially set value set from the maximum diameter portion 3M of the casing during excavation work. Allows excavation of soil without expansion (see FIG. 10). Further, since the body portion 70 is airtightly configured, air supplied from the outside can be temporarily stored in a high pressure state.

The connecting joint 71 has a hexagonal columnar shape in which the rotation axis 71R and the rotation axis 7R of the air tank coincide with each other. It is formed, and a flow passage 712 communicating with the inside of the air tank 7 is formed from the opening 711 (see FIG. 6. The rotation axis 71R and the rotation axis 7R are shown only in FIG. 6). The air tank 7 and the suspension shaft body 84, which will be described later, are rotatably connected by the connecting joint 71, and the air tank 7 is rotatably connected from an external air supply source via an air supply pipe 841 connected to the suspension shaft body 84. Air is supplied to (see FIGS. 1 and 6).

The connecting body 72 is a member for connecting to the excavating device 2a, and a through hole 721 having one end opened to the air tank 7 side and the other end opening to the piston member 41 side to which the other end is connected is substantially equal in the circumferential direction. A plurality of intervals (four in total in this embodiment) are formed at intervals. The air tank 7 and the excavator 2a can be connected by the connecting body 72, and the air in the air tank 7 can be supplied to the corresponding piston members 41 through the through holes 721 (see FIG. 6). The air flow direction is indicated by arrow AF in 6).

The air flow control member 73 is a sake cup-shaped member arranged on the surface of the connecting body 72 in the air tank 7, and is a bowl-shaped receiving portion 731 and a substantially truncated cone-shaped support 732 that supports the receiving portion 731. Has. The air flow control member 73 can control the flow direction of the air supplied through the connecting joint 71 in the air tank 7 (as shown by the arrow direction in FIG. 6). Specifically, first, the receiving portion 731 directly receives the air supplied from the connecting joint side 71, and then the air hits the receiving portion 731 and rebounds and swirls in the air tank 7, and penetrates the connecting body 72 at different timings. By flowing into the hole 721, the air flow is controlled. By changing the flow of air in the air tank 7 in this way, the arrival time of the air introduced from the air tank 7 to the piston member 41 can be changed (see FIGS. 6 and 9).

The attachment 74 is provided with spiral blades 741 on the outer peripheral surface 740 of the body thereof, and the spiral blades 741 are formed with engaging recesses 742 at equal intervals in the circumferential direction (see FIG. 3). The spiral direction of the spiral blade 741 is the same as that of the spiral blade 321 provided on the casing 3. The spiral blade 741 acts with the rotation of the excavating device 2a during the excavation work, and thereby, the soil is discharged from the back of the excavation hole H1 toward the hole opening H2 of the excavation hole to reach the position of the air tank 7. Can be further sent to the hole H2 of the drilling hole (see FIG. 10).

Since the attachment 74 has a structure that can be attached to and detached from the air tank 7, even if the spiral blade 741 is damaged by the excavation work, the attachment 74 only needs to be replaced, which contributes to the reduction of the work cost. However, the configuration is not limited to the above, and for example, a mode in which a spiral blade is directly provided on the body 70 of the air tank 7 is not excluded.

When the spiral blade 741 is attached to the air tank 7, the maximum diameter portion 74M of the attachment (that is, the position of the protruding tip of the spiral blade 741) is substantially the same as the maximum diameter portion 3M of the casing (same or slightly smaller diameter). ), This enables soil removal without expanding the excavation hole H1 from the initially set value during excavation work (see FIGS. 5 and 10).

Further, the engaging recess 742 is fitted with a locking convex portion (not shown) of the rotary drive device 8 described later, transmits the driving force from the rotary drive device 8 to the air tank 7, and excavates the air tank 7 and the like. The device 2a can be rotated. An engaging structure (not shown) is provided between the air tank 7 and the attachment 74, and the attached attachment 74 is integrated without idling around the air tank 7 by the engaging structure (not shown). It is designed to rotate in the axial direction. As the engaging structure portion, for example, a known engaging structure such as a concave portion and a convex portion, a fixing pin and a pin hole can be adopted.

<Rotation drive device>
In the present embodiment, the rotation driving device 8 includes a main body 80 having a rotary table 81 having an insertion hole 811 penetrating in the vertical direction, and support legs 82 having an outrigger structure for supporting the main body 80. .. The rotary table 81 has a drive unit (not shown) composed of a hydraulic motor, a gear device, and the like. Further, on the inner wall of the insertion hole 811 of the rotary table 80, a locking ridge portion (not shown) is formed in a direction along the central axis of the insertion hole 811.

By providing the above-described configuration, the rotary drive device 8 has a locking ridge provided in the device and a spiral blade of the excavator 2a when the excavator 2a is passed through the insertion hole 811 of the rotary table 81. The locking recesses 324 and 742 formed in the 321 and 741 are slidably locked, so that the excavator 2a attached to the rotary drive device 8 can be lowered by its own weight. Since the locking protrusions and the locking recesses 324 and 742 are in the locked state, the driving force from the rotary driving device 8 is applied to the excavating device 2a to rotationally drive the excavating device 2a in the horizontal direction. Can be done. Since the rotary drive device 8 has a known structure as disclosed in, for example, Japanese Patent Application Laid-Open No. 2011-269555, the description of the structure and operation is limited to the above-mentioned outline description, and the details will be omitted.

[Second Embodiment]
The excavation device 2b shown in FIGS. 11 and 12 is obtained by applying the excavation bit group 5b, which is the first arrangement mode 52, to the above-mentioned excavation device 2a. Further, in the air tank 7b, a flat bar 743 is applied instead of the spiral blade on the outer surface of the body portion 70. As for the excavator 2b, the rotary drive device 8 in the rotary excavator 1a described above can be used, but the description thereof will be omitted. In addition, the common parts (casing, drive unit, excavation bit) and the parts (casing, drive unit, excavation bit) described in the rotary excavator 1a are designated by the same reference numerals, the structure and operation thereof will be omitted, and only the differences will be described.

(Drilling equipment)
The excavation device 2b is composed of a casing 3b, a drive unit 4 mounted on the casing 3b, and a plurality of excavation bits 6D1, 6E1, 6E2 (hereinafter, referred to as "6D1 to 6E2" in all of these descriptions). The drilling bit group 5b having the first arrangement mode 52 is provided.

<Casing, drive unit, air tank>
In the present embodiment, a total of three through holes for inserting the excavation bit formed in the chuck guide 36 of the casing 3b are formed at substantially equal intervals in the circumferential direction, and the drive unit 4 is housed in the casing 3b. It is composed of the three piston members 41 (not shown). The piston members 41 have different diameters and are set so that the weights of the built-in pistons (not shown) are different (see FIG. 12).

Specifically, in the drive unit 4 of the present embodiment, the piston of the piston member 41 connected to the excavation bit 6D1 described later has a diameter of 10 inches (254 mm) and a weight of 46 kg in the clockwise circumferential direction. The piston of the piston member 41 connected to the excavation bit 6E1 adjacent to the excavation bit 6D1 on the clockwise side has a diameter of 8 inches (203.8 mm) and a weight of 31 kg, and the excavation bit 6E1 has a clockwise side. The piston of the piston member 41 connected to the excavation bit 6E2 adjacent to the excavation bit 6E2 has a diameter of 6 inches (152.4 mm) and a weight of 23 kg. While suppressing the increase in the weight of the entire device and the increase in the consumption of working fluid (air) to the minimum necessary, the effects of suppressing the formation of the central convex portion H6 and suppressing the generation of the central deformed portion H7 during hard rock excavation are further enhanced. Can be enhanced.

The flat bar 743 is a ridge provided on the body 70 of the air tank 7b and has a substantially quadrangular cross section and extends along the long axis direction of the air tank 7b. In the embodiment, four locations are provided (see FIG. 11).

When using an excavator 2b provided with a flat bar, the rotary drive device replaces the rotary table with a locking ridge formed on the inner wall of the insertion hole described in the description of the first embodiment. , The locking recess shall be formed in the direction along the central axis of the insertion hole. In this case, the rotary drive device has the above-mentioned configuration, so that when the excavator 2b is passed through the insertion hole of the rotary table, the locking recess provided in the device and the flat bar 743 of the excavator 2b are formed. It is slidably locked so that the excavator 2b attached to the rotary drive can be lowered by its own weight. Since the flat bar 743 and the locking recess are in the locked state, the driving force from the rotary driving device is applied to the drilling device 2b, and the drilling device 2b can be rotationally driven in the horizontal direction.

<Excavation bit, excavation bit group>
See FIG. The excavation bit group 5b is provided on the object to be excavated side of the casing 3b, and is composed of a plurality of excavation bits 6D1 to 6E2 that can move forward and backward in the axial direction of the casing 3b by receiving a driving force, and each striking surface 65b is the casing 3b. It is arranged around the rotation axis 3R of.

The excavation bit group 5b is provided on the casing 3b, and a plurality of excavation bits 6D1 to 6E2 in which the ridge striking portion 655 protruding from the striking surface 65b in the striking direction is formed along the peripheral edge of the casing 3b are excavated. It is configured so that the first hit can be applied to the object H by the ridge hitting portion 655. As a result, the drilling device 2b can deal with not only the soft layer H5 but also the hard rock H4 like the drilling device 2a, so that it can handle both the soft layer H5 and the hard rock H4 without changing the equipment. This makes it possible to save time and effort due to replacement of equipment. In addition, even when excavating hard rock, the excavation work can be performed with relatively low noise and low vibration.

The excavation bits 6D1 to 6E2 have corners 67b formed on the rotation axis 3R side of each striking surface 65b. The excavation bit group 5b is the first arrangement mode 52 in which only one of the striking surfaces 65 (the striking surface of the excavation bit 6D1) is arranged so as to overlap the rotation axis 3R, and the rotation axis of each striking surface 65b. The edges on the 3R side are assembled so as to be close to each other in the vicinity of the rotation axis 3R. Each striking surface 65b is on a substantially orthogonal surface of the rotation axis 3R of the casing 3 and can impact the object to be excavated H.

As for the excavation bits 6D1 to 6E2, like the excavation device 2a, each excavation bit 6D1 to 6E2 can be arranged so that there is almost no gap between the rotation axis 3R of the casing and its vicinity, and the excavation bit group. 5b can be the first arrangement mode 52, which is the above-mentioned overlapping arrangement of the rotation axis.

According to this rotation axis overlapping arrangement, the striking surface 65b of the excavation bit 6D1 can always be in a state of overlapping with the rotation axis 3R and its vicinity, and when the excavation bit 6D1 moves in the rotation direction, the angle can be set. Since the striking surface 65b of the excavation bit 6D1, which is a region wider than the portion 67b, excavates while constantly passing through the rotation axis 3R and its vicinity, the load is concentrated on the corner portion 67b and a small number of chips 651 in the corner portion 67b. This can suppress the formation of the central convex portion H6 during excavation of hard rock and also suppress the generation of the central deformed portion H7.

Further, in the present embodiment, the above-mentioned second arrangement mode 52 is a striking surface 65b in the vicinity of the corner portion 67b extending from the outer periphery of the rotation toward the rotation axis 3R in the excavation bit 6D1 in the direction of the rotation axis. A part of the above is arranged so as to overlap with the rotation axis 3R. With this configuration, the above-mentioned striking surface 65b and the rotary axis 3R can be overlapped with each other with a sufficient margin, and a part of the striking surface 65b rotates during the rotary excavation work. Since excavation is performed in a state where the axis 3R and its vicinity are always overlapped with each other, the effects of suppressing the formation of the central convex portion H6 and suppressing the generation of the central deformed portion H7 during hard rock excavation can be further enhanced. ..

More specifically, the excavation bit group 5b is configured by combining one excavation bit 6D1 and two excavation bits 6E1 and 6E2 having the same shape in a three-pronged shape. The striking surface 65b near the corner of 6D1 is arranged beyond the rotation axis 3R (in other words, including the rotation axis 3R), and each of the excavation bits 6E1 and 6E2 has the rotation axis 3R. They are arranged adjacent to each other with the diameter line L2 of the passing excavation part in between.

The excavation bit 6D1 and the excavation bits 6E1 and 6E2 are different in shape and size such as the striking surface 65b as described later (the excavation bits 6E1 and 6E2 are set smaller than the excavation bit 6D1). ), As a result, only the striking surface 65b of the excavation bit 6D1 overlaps with the rotation axis 3R in the direction of the rotation axis, and the excavation bits 6E1 and 6E2 have both the side portion 66b and the corner portion 67b of the rotation axis. It has a structure that does not overlap with the heart 3R. Further, the corner portions 67b of the excavation bits 6D1 and the excavation bits 6E1 and 6E2 are arranged at locations that are about 5.4% of the distance from the rotation axis 3R to the outer peripheral edge of the casing 3b with reference to the rotation axis 3R. ing.

The excavation bit 6D1 is one of a first side wall surface 624a having an arcuate end face view and a first side wall surface 624a arranged in a shape along a part of the outer surface 31 of the body of the casing 3b in a state of being attached to the chuck guide. Connected to the side edge and connected to the second side wall surface 624b extending to the rotation axis 3R side in the attached state and the other side edge of the first side wall surface 624a, and connected to the other side edge of the rotation axis 3R side in the attached state. The third side wall surface 624c extending to the center of the rotation is connected to the side edge opposite to the first side wall surface 624a of the second side wall surface 624b, and is directed to the rotation axis 3R side and the head portion (reference numeral omitted) in the horizontal major axis direction. The fourth side wall surface 624d is connected to the end opposite to the first side wall surface 624a of the third side wall surface 624c, and is directed toward the rotation axis 3R side of the casing 3b and the horizontal major axis direction of the head portion. It is composed of a fifth side wall surface 624e that is extended and connected to the end opposite to the second side wall surface 624b of the fourth side wall surface 624d to form a sharp corner portion 67b. The lengths of the side portions 66b corresponding to the fourth side wall surface 624d and the fifth side wall surface 624e on the striking surface 65b are equal sides, and the lengths of the side portions 66b corresponding to the second side wall surface 624b and the third side wall surface 624c. The dimensions are equal (see FIG. 12).

On the other hand, the excavation bits 6E1 and 6E2 have the same configuration as the excavation bit 6D1 for the first side wall surface 624a, but the side portion 66b corresponding to the second side wall surface 624b is the side corresponding to the third side wall surface 624c. The excavation bit 6D1 and the excavation bit 6D1 are unequal sides longer than the portion 66b, and the side portion 66b corresponding to the fifth side wall surface 624e is longer than the side portion 66b corresponding to the fourth side wall surface 624d. It's different.

By forming the striking surfaces 65b of the excavation bits 6D1 and the excavation bits 6E1 and 6E2 into the above-mentioned shapes, the excavation bits 6D1 to 6E2 can be arranged so that there is almost no gap in the rotation axis 3R of the casing 3b. At the same time, the excavation bit group 5b can be set to the first arrangement mode 52, which is the above-mentioned rotation axis overlapping arrangement.

[Modification example]
In addition to the embodiments described in the first embodiment and the second embodiment (hereinafter abbreviated as "first and second embodiments"), the present invention also includes the embodiments described in the following modifications.

<Excavation bit group and excavation bit>
(Modification example 1, modification 2)
13 (a) is a modification 1 which is another aspect of the excavation bit group 5a shown in FIG. 7, and FIG. 13 (b) is a modification 2 which is another aspect of the excavation bit group 5b shown in FIG. be. Modifications 1 and 2 will be described with reference to FIG. Since the excavation bit group 5c and the excavation bit group 5d are the same as those of the first and second embodiments except for the differences described later, the description of the structure and the action and effect will be omitted.

The excavation bit group 5c, which is the first modification, is similar to the excavation bit group 5a shown in FIG. 7 in that it is composed of four excavation bits 6F1, 6F2, 6F3, and 6F4 (hereinafter referred to as “6F1 to 6F4”). The second arrangement mode 51 described above is not applied, and the corner portions 67c located at the tips of the excavation bits 6F1 to 6F4 are non-overlapping arrangements on the rotation axis 3R, and the lengths of the side portions sandwiching the corner portions 67c. Is the same (equal sides) configuration, and each excavation bit 6F1 to 6F4 is different from the excavation bit group 5a in that the structure including the shape of the striking surface is the same.

According to the excavation bit group 5c, since each excavation bit 6F1 to 6F4 has the same structure, it is not necessary to manufacture, purchase or store two types of excavation bits as in the excavation bit group 5a, and only one type can be procured. I'm done. As a result, for example, when used as a replacement part or a spare part, even if any excavation bit is missing, only one type of excavation bit needs to be prepared, so that waste such as a surplus of one type of excavation bit can be reduced. In addition, space can be saved during storage, and the number of replacement parts and the like to be carried to the site can be reduced.

The excavation bit group 5d, which is the second modification, is the same as the excavation bit group 5b shown in FIG. 12 in that it is composed of three excavation bits 6G1, 6G2, and 6G3 (hereinafter referred to as “6G1 to 6G3”). The first arrangement mode 52 of the above is not applied, and the corner portions 67d located at the tips of the excavation bits 6G1 to 6G3 are non-overlapping arrangements on the rotation axis 3R, and the lengths of the side portions sandwiching the corner portions 67d are the same. It is different from the excavation bit group 5b in that the excavation bits 6G1 to 6G3 have the same structure including the shape of the striking surface.

According to the excavation bit group 5d, since each excavation bit 6G1 to 6G3 has the same structure, it is not necessary to manufacture, purchase or store two types of excavation bits as in the excavation bit group 5b, and only one type can be procured. I'm done. As a result, for example, when used as a replacement part or a spare part, even if any excavation bit is missing, only one type of excavation bit needs to be prepared, so that waste such as a surplus of one type of excavation bit can be reduced. In addition, space can be saved during storage, and the number of replacement parts and the like to be carried to the site can be reduced.

(Modification 3, Modification 4, Modification 5)
FIG. 14A shows a modified example 3 in which a ridge striking portion is not formed on the excavation bit of the excavation bit group 5a shown in FIG. 7, and FIG. 14B shows the excavation bit of the excavation bit group 5b shown in FIG. Modification example 4 in which the ridge striking portion is not formed, FIG. 14 (c) shows a modification in which the excavation bit group 5 has two excavation bits and the ridge striking portion is not formed in the excavation bit. It is 5. Modifications 3 to 5 will be described with reference to FIG. Since the excavation bit group 5e to the excavation bit group 5g are the same as those of the first and second embodiments except for the differences described later, the description of the structure and the action and effect will be omitted.

The excavation bit group 5e, which is the third modification, is composed of four excavation bits 6Q1, 6Q2, 6R1, and 6R2 (hereinafter referred to as “6Q1 to 6R2”) as in the excavation bit group 5a shown in FIG. It is the same in some respects, but differs from the excavation bit group 5a in that the above-mentioned ridge striking portion is not formed. According to the excavation bit group 5e, the object to be excavated H1 hit by the excavation bit group 5e can be excavated evenly, and the central convex portion is not formed in the center of the back side of the excavation hole and is substantially flat. be able to.

The excavation bit group 5f, which is the fourth modification, is composed of three excavation bits 6S1, 6T1, 6T2 (hereinafter referred to as “6S1 to 6T2”) as in the excavation bit group 5b shown in FIG. 12, and is the first arrangement mode. However, it differs from the excavation bit group 5b in that the above-mentioned ridge striking portion is not formed. According to the excavation bit group 5f, the object to be excavated H1 hit by the excavation bit group 5f can be excavated evenly, and the central convex portion is not formed in the center of the back side of the excavation hole and is substantially flat. be able to.

In the excavation bit group 5g which is the modification 5, the striking surface portion 65g is composed of semicircular excavation bits 6U1 and 6V1, and only the striking surface portion 65g of the excavation bit excavation bit 6U1 is the rotation axis 3R in the direction of the rotation axis. On the other hand, the excavation bit 6V1 has a configuration (first arrangement mode) that does not overlap with the rotation axis 3R. According to the excavator equipped with the excavation bit group 5 g of this modified example, although the excavation device of the first and second embodiments is handed over in terms of quietness and low vibration, it has lower vibration and lower vibration than the single-bit down-the-hole hammer. Since it has low noise and has a larger striking force than the excavating equipment of the first and second embodiments, it can be suitably used for an object to be excavated containing a large amount of hard rock.

(Modification 6 and Modification 7)
In the first and second embodiments, the opening 653 of the flat striking portion 652 is one for each excavation bit, but the present invention is not limited to this, and for example, the excavation of the modified example 6 shown in FIG. Like the bit 6P1 or the excavation bit 6N1 of the modified example 4 shown in FIG. 15B, the air flow path is branched in the head portion, and the opening 653 formed in the flat striking portion 652 is set to 2 or more. You can also do it.

Further, in the first and second embodiments, the exhaust guide groove 654 forms two rows in different directions from the rim of the opening 653 (since the two rows merge around the opening 653, it can also be expressed as one). However, the present invention is not limited to this, and for example, the exhaust guide groove to be formed may have one or three or more grooves, and is formed toward the same direction such as the first side wall surface. It may be the mode to be used. For example, the exhaust guide groove 654 of the excavation bit 6P1 of the modified example 6 shown in FIG. The exhaust guide groove 654 of the excavation bit 6N1 of the modified example 7 shown in FIG. 15 (b) is formed in two different directions from the rims of the two openings 653. There is.

In each of the above-described embodiments and modifications, the chips 651 are planted and distributed in the excavation bit 6A1 and the like, but the present invention is not limited to this, and for example, a plurality of concave grooves are formed on the striking surface. However, as a result of the flat surface and the concave portion being continuous, the flat surface may be substantially a convex portion to replace the function of the chip.

In the arrangement mode constituting the excavation bit group in each of the above-described embodiments or modifications, the tip of each excavation bit is from the rotation axis to the outer peripheral edge of the casing with reference to the rotation axis of the casing. It is preferable that it is set so as to fit inside a radius region of 5% to 30% of the distance. If it is less than 5%, the corners are too close to the center of rotation, and a central convex portion H6 as shown in FIG. 18C is formed in the center of the back side of the excavation hole during hard rock excavation. It is not preferable because the central deformed portion H7 may be generated in the bit. On the other hand, if it exceeds 30%, an excavation bit smaller than the diameter of the piston member is generated, and the transmission efficiency of the striking force may decrease. After all, it is not preferable.

In each of the above-described embodiments or modifications, the head portion 62 has a pentagonal surface shape of the striking surface 65, but the present invention is not limited to this, and for example, the surface shape of the striking surface is semicircular. Or, it may be a fan shape, a substantially triangular shape, a substantially square shape, or the like, and in a state where a plurality of excavation bits are attached to the excavation device, the side wall portion facing the rotation axis side of one excavation bit is at an opposite position or. Any shape may be used as long as it can be abutted against the side wall portion of another excavation bit at an adjacent position facing the rotation axis side so that there is almost no gap between them. Further, the head portion may have a frustum shape or the like whose bottom surface is a striking surface as well as a prismatic shape.

In each of the above-described embodiments or modifications, the ridge striking portion 655 is set to have an inclination angle 65A of the inclined surface 656 set to 35 °, but the inclination angle is not limited to 35 °, and the inclination angle is, for example, 20. It is preferably set within the range of ° to 60 °, more preferably 30 ° to 50 °. If this inclination angle is less than 20 °, the inclined surface on the entire striking surface becomes too wide and becomes flat as a whole, making it difficult to exert a striking force that bites into the hard rock, and a central convex portion is generated in the excavation hole. On the other hand, if this inclination angle exceeds 60 °, the ridge striking part protrudes too sharply, and the ridge striking part tends to be chipped when hitting a hard rock, which is also not preferable. be.

In each of the above-described embodiments or modifications, the protrusion height 65H of the ridge striking portion 655 is set to 3 cm from the flat striking portion 652, but the present invention is not limited to this, and for example, this height. Is preferably at a height of 2 cm to 6 cm, more preferably 3 to 5 cm from the flat striking portion. If the protrusion height is less than 2 cm, the protrusion height from the flat striking part is low, and it is difficult to exert a striking force that causes the rock to bite into the rock. Therefore, when hitting a hard rock, the striking portion of the ridge is likely to be chipped, which is also not preferable.

<Casing>
(Modification 8 and Modification 9)
In the first and second embodiments, the spiral blade 321 and the reinforcing rib 322 are provided on the outer surface 31 of the body portion of the casing 3, but the present invention is not limited to this, and for example, the modified example 5 shown in FIG. 16A is shown. A mode in which the spiral blade 321a is provided in the longitudinal direction of the outer periphery of the body of the casing 3c as in the excavator 2c of the above, and the body of the casing 3b as in the excavator 2d of the modification 6 shown in FIG. 16B. It does not exclude various deformations such as a mode in which a flat bar 325 parallel to the rotation axis of the casing extending in the longitudinal direction of the outer circumference is provided.

In the casing 3, the voids formed between the inner wall of the casing 3 and the drive unit 4 may be filled with granules such as sand as a vibration-proof material or a sound-proof material (not shown). Further, when the weight of the piston 411 of each piston member 41 constituting the drive unit 4 is set to be non-uniform, a counter weight may be arranged in this gap in order to prevent malfunction (not shown).

Further, the drilling device 2a or the like in each of the above-described embodiments or modifications has a structure in which the casing 3 and the air tank 7 are detachable, but the structure is not limited to this, and for example, the casing and the air tank are detachably integrated. It does not exclude the structure that became. Further, in this non-detachable type excavator, the outer circumference may be flush with each other, and spiral blades or flat bars extending in the long axis direction may be provided.

<Drive unit>
In the first and second embodiments, the drive unit 4 is composed of three or four piston members 41 in the casing as described above, but the present invention is not limited to this, and for example, at least for each excavation bit. It is preferable that one piston member is used.

In each of the above-described embodiments or modifications, the drive unit 4 is set so that the piston members 41 have different diameters and the weights of the built-in pistons 411 are different (all different modes). For example, a piston member having a maximum striking force is applied only to a striking surface having a maximum area, and a common piston member having a weaker striking force than a piston member having a maximum striking force is applied to other striking surfaces. It may be an aspect (partially common aspect) or the like. It should be noted that the pipe diameter of the piston member is common, and the mode in which the weight (striking force) is changed depending on the length of the built-in piston is not excluded.

Further, when the drive unit has a partially common mode, for example, when the drive unit is a set of four piston members, two sets of two types of piston members having different piston weights are combined, and the drive unit is a set of three piston members. In the case of, the piston member having the maximum striking force may be applied to only one striking surface having the maximum area, and the common piston member having a slightly weak striking force may be applied to the other two striking surfaces. For example, it is possible to make a difference in striking force for each excavation bit, and it is possible to reduce the number of parts (some parts are shared) compared to all different modes, and to reduce costs during manufacturing and operation. Can be done.

Further, the drive unit is not limited to the above-mentioned structure, and is not limited to the above-mentioned structure. There is no particular limitation as long as the pistons have a structure that allows them to move forward and backward individually. Also in this case, as described above, the weight of each piston can be set to be different.

<Storage tank>
In each of the above-described embodiments or modifications, the air flow control member 73 has a cup shape, but is not limited to this, and for example, a disk-shaped plate having holes at predetermined intervals in the circumferential direction is formed. A structure that is rotatably attached along the surface of the connecting surface inside the storage tank so as to intermittently close the above-mentioned through holes formed in the connecting body as the rotation occurs, and each from the storage tank to the piston member. The shape or structure is not particularly limited as long as the air in the storage tank does not flow into each piston member at the same timing, such as a structure in which the length of the path is provided to be long or short.

In addition, a plurality of other openings and flow passages formed in the connecting joint of the storage tank may be formed (these are referred to as "other flow passages" for convenience in this paragraph), and in this case, for example, soil reinforcement. A fluid such as a material can flow into another flow path and be discharged into the excavation hole from the excavated object side of the excavator through a supply pipe passing through the storage tank.

<Rotation drive device>
The rotary drive device 8 shown in the first embodiment is a mode in which a rotational force is applied to the excavator 2a in a state where it can be lowered by its own weight of the excavator 2a, but the present invention is not limited to this, and for example, the rotary drive device 8 is rotationally driven. The device may have a mechanism for pushing the attached excavation device toward the object to be excavated, and in that case, it can be suitably used particularly for a wall-shaped object to be excavated such as a rock wall. Further, the rotary drive device 8 shown in the first embodiment is provided in a table shape, but is not limited to this, and has, for example, a holding portion to be attached to the body of the excavating device. The device is not particularly limited as long as it is a device capable of applying a rotational force to the excavating device, such as a rotary driving device in which a rotational force is applied to the excavating device via a holding portion.

The terms and expressions used in the present specification and the utility model registration claims are for explanatory purposes only and are not limited in any way, and are described in the present specification and the utility model registration claims. There is no intention to exclude terms or expressions equivalent to these features and some of them. In addition, it goes without saying that various modifications are possible within the scope of the technical idea of the present invention. In addition, words such as first and second do not mean grade or importance, but are used to distinguish one element from another.

1 Rotary excavator 2a, 2b, 2c, 2d Excavator 3, 3b, 3c, 3d Casing 3R Rotating axis 3C Circumferential direction 31 Body outer surface 32 Screw part 321, 321a Spiral blade 322 Reinforcing rib 324 Engagement recess 325 Flat Bar 33 Storage tank side lid 331 Insertion hole 34 Excavated side lid 341 Insertion hole 35 Chuck guide 351 Through hole 36 Drive chuck 370 Bolt 371 Nut 3V Virtual surface 3M Maximum diameter part of casing 4 Drive unit 41 Piston member 411 Piston 412 Cylinder 5a, 5b, 5c, 5d, 5e, 5f, 5g Drilling bit group 51 Second placement mode 52 First placement mode 6A1, 6A2, 6B1, 6B2, 6D1, 6E1, 6E2, 6F1, 6F2, 6F3, 6F4, 6G1, 6G2, 6G3, 6N1, 6P1, 6Q1, 6Q2, 6R1, 6R2, 6S1, 6T1, 6T2, 6U1, 6V1 Excavation bit 6C Approximately orthogonal surface of the rotation axis of the casing 61 Connection shaft 611 Opening 62 Head 621 Air flow path 622 Joint 623a, 624a 1st side wall surface 623b, 624b 2nd side wall surface 623c, 624c 3rd side wall surface 623d, 624c 4th side wall surface 623e, 624e 5th side wall surface 65, 65b, 65c, 65d, 65e, 65f, 65g Strike surface 651 Chip 652 Flat striking part 653 Opening 654 Exhaust guide groove 66, 66b Side part 67, 67b, 67c, 67d, 67e, 67f, 67g Square part 655 Protruding striking part 656 Inclined surface 65A Inclined Angle 65H Protrusion height 661 Edge 7, 7b Storage tank 7R Storage tank rotation axis 70 Body 71 Connection joint 71R Connection joint rotation axis 711 Opening 712 Flow passage 72 Connection body 721 Through hole 73 Air flow control member 731 Receiving part 732 Support AF Air flow direction 74 Attachment 740 Body outer peripheral surface 741 Spiral blade 742 Engagement recess 743 Flat bar 74M Maximum diameter part of attachment 8 Rotation drive device 80 Main body 81 Rotating table 811 Insertion hole 82 Support leg 84 Suspended shaft body 841 Air supply pipe H Excavated object H1 Excavation hole H2 Excavation hole hole mouth H3 Hole bottom surface H4 Hard rock H5 Soft layer H6 Central convex part H7 Central deformation part L2 Diameter line 9 Excavator 91 Central bit 92 Peripheral bit 93 Prototype 930 Excavation bit 931 Strike surface 933 Square part 934 Tip 9R Rotation axis

Claims (10)

A tubular casing that can rotate in the circumferential direction,
It has a plurality of cylinders housed in the casing and a piston built in each cylinder and actuated by a working fluid to apply a striking force to the drilling bit, the weight of at least one piston being that of the other piston. A drive unit that can supply driving force, which is set to be different from the weight,
It has a plurality of excavation bits arranged around the rotation axis of the casing and capable of advancing and retreating along the axial direction of the casing by receiving the driving force, and the excavation bits exert themselves by receiving the driving force. An excavator comprising an excavation bit group set in any aspect in which the striking force to be performed is different for each excavation bit, or at least one of the excavation bits is different from other excavation bits. The excavator according to claim 1, wherein the pipe diameter of the cylinder containing the maximum weight of each piston among the cylinders is set to the maximum. The excavator according to claim 1, wherein the pipe diameter of the other cylinder is set in the range of 100% to 50% with respect to the one having the largest pipe diameter among the cylinders. The excavator according to claim 1, wherein the weight of the other piston is set in the range of 100% to 20% with respect to the one having the maximum weight among the pistons. The first arrangement mode in which the excavation bit group is arranged such that only one of the striking surfaces of one excavation bit in each excavation bit overlaps with the rotation axis, or the striking surface of the excavation bit. A corner portion is formed on the rotation axis side, and only the edge portion on the rotation axis side of a set of the same striking surfaces arranged so as to face each other across the rotation axis overlaps with the rotation axis, and the said By any of the second arrangement modes in which the tips of the corners are arranged so as not to overlap with the same rotation axis, the edges of the respective striking surfaces on the rotation axis side are close to each other in the vicinity of the same rotation axis. The excavator according to any one of claims 1 to 4, which is configured as such. The drive unit is the excavation bit in which the striking surface is arranged so as to overlap the rotation axis in the first arrangement mode, or the striking surface is the side edge of the rotation axis in the second arrangement mode. 5. Claim 5 is set to give the maximum striking force among the excavation bits constituting the excavation bit group to any of the excavation bits arranged only in the portion overlapping the rotation axis. The excavator described in. Each of the excavation bits has a connecting shaft portion that receives a driving force supplied from the driving unit, and a head portion that is connected to the connecting shaft portion and has a striking surface portion on the opposite side of the connecting shaft portion. However, the striking surface portion includes a substantially flat flat striking portion and a ridge striking portion protruding higher than the flat striking portion, and the ridge striking portion is the excavation in the direction of the rotation axis of the casing. The excavator according to any one of claims 1 to 6, which is formed in an arc shape along an edge along the outer peripheral edge of the bit group. The excavator according to any one of claims 1 to 7, which is connected to the side of the casing opposite to the excavation bit group and includes a storage tank capable of storing the working fluid. The excavator according to claim 8, wherein the storage tank has a working fluid distribution unit that appropriately distributes the working fluid so that the timing of supplying the driving force to the excavation bit by the drive unit is different. It has a tubular casing that can rotate in the axial direction, a plurality of cylinders that are housed in the casing, and a piston that is built in each cylinder and is actuated by a working fluid to apply a striking force to the excavation bit. A drive unit capable of supplying a driving force, the weight of at least one piston being set to be different from the weight of the other piston, and the driving force arranged around the rotation axis of the casing. Including a plurality of excavation bits that can move forward and backward along the axial direction of the casing in response to the above, the striking force that the excavation bit exerts by receiving the driving force differs for each excavation bit, or at least. An excavator having an excavation bit group set in any aspect, wherein the same excavation bit is different from another excavation bit.
A rotary excavator including a rotary drive device that applies a rotational force to the excavator.

Images