JP7177471B2 - Drilling rigs and rotary excavators - Google Patents

Description

The present invention relates to drilling rigs and rotary drilling machines. More specifically, the impact force is improved compared to a conventional drilling device (hereinafter referred to as "conventional device"), and the drilling device is broken in a hole drilled during drilling work (hereinafter referred to as "drilled hole"). It relates to a device capable of suppressing the occurrence of an accident in which a part remains in an excavated hole (hereinafter referred to as "fracture residual accident").

In recent years, especially in construction work in urban areas, vibration and noise generated during excavation work accompanying foundation pile driving, etc. have become a problem. proposes a rotary excavator described in . The excavator of this rotary excavator is shown as an excavator 9 in FIG.

The excavator 9 performs excavation work (hereinafter referred to as "rotary excavation work") by being imparted with rotational motion by a rotary drive device (not shown). and has a plurality of bits consisting of a bit arranged at the center of rotation (hereinafter referred to as "central bit 91") and bits arranged around this central bit (hereinafter referred to as "peripheral bit 92"). , each bit is configured to be impact-driven with a time lag from each other. Compared to conventional down-the-hole hammers that hit the ground by moving a single bit of approximately the same diameter as the drilled hole, this makes the bit hitting cycle faster, instead of the bit hitting once. By reducing the impact on the ground caused by each impact, it is possible to perform excavation work with low vibration and low noise.

JP 2007-92447 A

By the way, when the inventors of the present invention operated a rotary excavator using the excavator 9, it was found that the excavator 9 sometimes strikes the central bit 91 and the peripheral bit 92 at the same time. There was found. Even if such simultaneous impacts occur, excavation work can be performed with less vibration and noise than the conventional down-the-hole hammer. Prototype 93, which is an improved version of 9, was produced.

A prototype machine 93 shown in FIG. 12(a) does not have a central bit on the excavation surface, and has corners 933 formed by expanding the striking surface 931 of the peripheral bits in the direction of the rotation axis of the prototype machine 93. The tip angle of the corners 933 is located on the rotation axis 9R, and the corners 933 are arranged so as to face each other (hereinafter, a peripheral bit having such a configuration is referred to as "excavation bit 930"). In general, a plurality of chips made of cemented carbide are implanted on the striking surface of the drilling bit to form convex portions with respect to the striking surface. The excavation bit 930 of the prototype 93 is similarly configured to have a tip 934 implanted therein.

When the inventors of the present invention operated a rotary excavator using the prototype machine 93, it was found that the prototype machine 93 had a first problem related to impact force and a second problem related to a fracture residual accident. There was found.

The first problem is that when the inventors of the present invention perform excavation work using the prototype machine 93, the excavation work of the ground that is predicted to consist of a soft layer (hereinafter referred to as "soft layer") composed of earth, sand, soft rock, etc. It turned out when I hit an unexpected hard rock.

The prototype machine 93 enables excavation work with low vibration and low noise by reducing the impact on the ground caused by each impact of the excavation bit 930. , the hard rock cannot be crushed due to insufficient striking power, or it takes time to crush the hard rock, or the excavation direction deviates along the slope of the hard rock because it cannot be crushed ( hereinafter referred to as "obstacles such as inability to crush hard rock due to insufficient striking power").

In such a case, it is possible to remove the prototype machine 93 once, replace it with a single bit type down-the-hole hammer with a large impact force, replace it again with the prototype machine 93 after crushing the hard rock, and restart the excavation work. , it took extra time and effort. During the work with the single bit type down-the-hole hammer, large vibration and noise were generated.

The second problem was discovered when the prototype machine 93 was similarly used for excavation work, and an accident occurred in which the prototype machine 93 was broken in the excavated hole and the tip remained in the excavated hole.

The prototype machine 93 has a structure in which the connection portion between the main body of the device and the connecting object (for example, the chuck guide to which the drilling bit is attached) is flat and connected in the longitudinal direction by connecting bolts. , when the excavator rotates in the excavated hole, it is resisted by earth pressure, and a shear load is applied in the longitudinal direction of the prototype machine 93, so that a large shear force is applied to the connection bolt.

If this state continues, the connecting bolt may break, and when the connecting bolt is broken, when the prototype machine 93 is pulled up from the excavated hole, the tip of the prototype machine 93 will remain (left behind) in the excavated hole rather than the broken part. In order to continue the excavation work, it is necessary to lift the remaining part, but the remaining part is also quite heavy and is in a state that it is contained in a narrow hole, so the labor, time, and cost required for the lifting work will be burdened. was big. It should be noted that there is a possibility that a similar accident may occur in the excavator 9 as well.

The present invention has been invented in view of the above points, and provides an excavator that can improve impact force compared to conventional equipment and can suppress the occurrence of fracture residual accidents in an excavated hole during excavation work, and , the purpose of which is to provide a rotary excavator.

In order to achieve the above object, the excavator of the present invention is provided rotatably about a rotation axis, and has a plurality of drive unit storage sections provided parallel to the rotation axis. A device main body having a body portion having a substantially solid structure except for the portion and a first connection portion formed on one end side, and a drive unit using air as a power source and disposed for each drive unit storage portion; a chuck guide in which a second connection portion connected to the first connection portion with a fitting structure is formed, and a plurality of guide holes, which are through holes that are linearly communicated with the drive unit storage portion, are formed; a plurality of excavation bits having a head portion including a connecting shaft portion that is inserted into and axially moved forward and backward upon receiving a driving force from the drive unit, and a striking surface provided at the tip of the connecting shaft portion; an air tank having a tank body connected to the other end side of the body and capable of feeding air to each drive unit, and an air introduction part capable of introducing air supplied from the outside into the tank body; An air distribution part capable of distributing the air supplied from the inside of the air tank to the drive unit so that part or all of the drilling bits advance and retreat at different timings.

Here, since the device main body is provided rotatably about the rotation shaft, when a rotational force is applied in combination with the rotation driving device, the device main body rotates about the rotation shaft, and the plurality of excavation bits are generated. rotary excavation work can be performed by

The main body of the apparatus can store each drive unit by forming a plurality of drive unit storage sections in the body. In addition, since the drive unit storage section is provided in parallel with the rotation shaft, the drive force from the drive unit is transmitted linearly to the excavation bit, and the loss of power transmission can be reduced.

The drive unit storage section is arranged in parallel with the rotation axis so that it is arranged around the rotation axis. It is possible to suppress unnecessary expansion of the excavated hole due to vibration caused by shaft vibration and shaft vibration.

Furthermore, unlike the conventional device, the body is not a hollow cylinder, but a substantially solid column except for the drive unit storage section. , the impact force against an excavated object such as the ground (hereinafter referred to as "excavated object") is improved. In addition, due to the substantially solid structure, the rigidity is higher than that of the conventional device, and breakage due to the body is less likely to occur, so that the service life can be extended.

In addition, "substantially solid structure except for the drive unit storage part" means that the drive unit storage part and the liquid flow path, etc. are formed in addition to the drive unit storage part. It means an embodiment in which the portion to be removed has a solid structure, and is used in the sense of including a solid structure.

Since the first connecting portion is formed on one end side, the body portion can be connected to the second connecting portion formed on the chuck guide. As a result, the device body and chuck guide can be connected in a fitted state, and the device body and chuck guide that are connected in a fitted state are integrated and reinforced at the joint, thereby improving the shear strength. Therefore, it is possible to suppress the occurrence of residual fracture accident due to the connection portion, which was seen in the conventional device.

For example, when the first connection portion is a projection, the second connection portion is a recess. , the second connecting portion may be a convex portion. Moreover, the fitting structure may be such that a plurality of projections and recesses are provided in each of the first connection portion and the second connection portion.

The main body of the device has a drive unit that uses air as a power source, so that the device has good operability and does not generate waste such as liquid working fluid, which is a power source, and exhaust gas, reducing the environmental load. be able to. Further, in the main body of the apparatus, a drive unit is arranged for each drive unit storage section, that is, a plurality of drive units supply driving force to each drilling bit in a corresponding arrangement, thereby performing the drilling operation using a plurality of drilling bits. It can be performed.

In addition, since the drive units are arranged for each drive unit storage section, multiple drive units can be arranged around the rotating shaft in a well-balanced manner, reducing vibration caused by shaft shake during rotary excavation work. can be suppressed.

In the drilling apparatus of the present invention, since the chuck guide is formed with the second connecting portion, as described above, it can be connected to the first connecting portion of the device main body in a fitted state. They can be connected so that they rotate together.

Since the chuck guide is formed with a plurality of guide holes, a drilling bit can be attached to each guide hole. Furthermore, since each guide hole is a through hole that communicates linearly with the drive unit storage section, the connecting shaft section of the drilling bit can be inserted so as to move forward and backward in the axial direction, and the drive unit can be moved forward and backward. can be transmitted linearly to the drill bit.

In the drilling apparatus of the present invention, since each drilling bit has a connecting shaft portion, it can be fitted into each guide hole of the chuck guide and attached to the chuck guide.

Since the connecting shaft portion of the excavating bit is inserted into the guide hole, the driving force from the drive unit is transmitted to the base end of the connecting shaft portion, and the driving force is received so that the connecting shaft portion moves along the guide hole. As a result, the drilling bit as a whole, including the head portion, also moves forward and backward. As a result, the drilling bit hits the object to be excavated in front of the excavator with the striking surface of the head portion, so that the object to be excavated can be excavated.

Further, each drilling bit can be independently advanced and retracted by having the connecting shaft portion individually fitted into the guide hole.

By the way, the drive unit storage section is provided parallel to the rotation shaft, that is, it is configured to be provided around the rotation shaft. Since each guide hole of the chuck guide communicates with the drive unit storage portion and penetrates in the same axial direction, each guide hole of the chuck guide is also provided around the rotation shaft.

In other words, each drilling bit fitted into each guide hole of the chuck guide is arranged around the rotary shaft of the chuck guide. , each drilling bit hits the object to be excavated multiple times, so that the object to be excavated can be excavated evenly.

In the drilling apparatus of the present invention, the air tank has the air introduction portion, so that air can be introduced into the tank body. For example, the air may be introduced (supplied) from the outside by connecting a device such as a compressor to the air introduction portion.

By connecting the tank body to the other end side of the body of the device main body, the device main body and the air tank can be brought into a connected state, whereby the device main body and the air tank can be connected so as to rotate integrally. can. The air tank connected to the main body of the apparatus can supply the air introduced into the body of the tank to each drive unit. For example, the air may be supplied through a path that opens to the connecting surfaces of the apparatus main body and the air tank and is formed so that the air tank and the drive unit storage section communicate with each other in an air-permeable manner.

The drilling apparatus of the present invention is provided with the air distribution section, so that the air supplied to the drive unit can be distributed so that the timing of hitting the drilling bits is different. Since the drill bit strikes the excavated object and the simultaneous impact of the drilling bits on the excavated object is less likely to occur, the excavation work can be performed with less vibration and noise than a conventional down-the-hole hammer. Further, as a mode of distribution by the air distribution section, for example, air from the inside of the air tank to the drive unit is distributed by changing one of the supply amount and the supply timing, or by changing both the supply amount and the supply timing. is mentioned.

It should be noted that "some or all of the drilling bits have different timings" means that all the drilling bits advance and retreat at different timings, and that some of the drilling bits advance and retreat at different timings. It is used in the sense of including both. The arrangement of the air distribution section is not particularly limited. It fits well and is unlikely to be damaged by an external force, so it is more preferable from the standpoint of maintenance.

Further, in an end view of the excavator in the excavation direction, the striking surfaces of the respective excavating bits are arranged around the rotation axis of the chuck guide, and only one of the striking surfaces is arranged so as to overlap the rotation axis. Arrangement mode, or a set of striking surfaces in which corners are formed on the rotating shaft side of the striking surface, and only edges on the rotating shaft side of a pair of striking surfaces arranged to face each other across the rotating shaft overlap with the rotating shaft and or a second arrangement mode in which the tips of the parts are arranged so as not to overlap the rotation axis, and the edges of the striking surfaces on the rotation axis side are assembled so as to be close to each other in the vicinity of the rotation axis. In some cases, each drill bit may be mounted with little clearance at and near the axis of rotation.

According to this arrangement configuration of the drilling bits, even if the drilling bits arranged in the center of the drilling surface in the conventional device are eliminated, the drilling bits can uniformly drill the object to be drilled, especially hard rock. During excavation, it is possible to make the bottom of the excavated hole substantially flat without forming a convex undigged portion (hereinafter referred to as "central convex portion") at the center of the deep side of the excavated hole.

The central protrusion will be described in detail with reference to FIG. 12 . The present inventor further improved the excavator 9 and created a prototype 93 (see FIG. 12(a)) having the above-described configuration. When the inventor of the present invention performed excavation work using the prototype 93, he accidentally hit a hard rock in the ground. was formed (see FIG. 12(c)).

In addition, the vicinity of the corner portion 933 of each excavation bit 930 was worn away, and the striking surface 931 itself also had a central deformed portion H7 in a depressed state (see FIG. 12(b)). At a later date, when the excavation work on the hard rock was tried again, the formation of the central convex portion H6 and the occurrence of the central deformed portion H7 of the prototype 93 were again confirmed.

Although the reasons for the formation of the central convex portion H6 and the occurrence of the central deformed portion H7 are not necessarily clear, it is presumed that they are due to the following reasons.
(a) During the operation of the prototype machine 93, 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. In other words, the drilling bits 930 in the retracted state and the advanced state are mixed, and as a result, the loads (shaft load due to self-weight, impact load due to impact) applied to each drilling bit 930 are not evenly distributed, but are distributed in the advanced state. will concentrate on the drilling bit 930 of
(b) In addition, the edge of the striking surface 931 of the drilling bit 930 in the advanced state, or a portion close to the edge, is more likely to be worn away than other flat portions. the weaker the strength. In addition, since the corners and their vicinity are tapered and have a narrower area than the other portions, if the tips 934 are arranged at the same density as the other portions, the number of implantable tips 934 is reduced.
(c) As described above, the load concentrates on the drilling bit 930 in the advanced state, and furthermore, the load tends to concentrate on the corner 933 of the drilling bit 930 in the advanced state. A smaller number of the tips 934 that are formed are subjected to a greater load than the rest of the tips, which causes the tips 934 to wear out or break, such as the tips 934 falling off, at an earlier stage than the rest of the parts.
(d) The breakage of the tip 934 significantly reduced the excavation force near the corner 933 , causing a difference in excavation force from the other portions of the striking surface 931 , and directly In the excavating state, the corner portion 933 and its vicinity are worn or plastically deformed together with the base portion, further reducing the excavating force.
(e) As a result, due to the difference in excavation force between the vicinity of the rotary shaft 9R and other portions of the striking surface 931, a central convex portion H6 having a shape in which the central portion swells more than the outer periphery on the hole bottom surface H3 of the excavated hole H1. formed,
(f) Further, the end of the excavated object side of the prototype machine 93 during excavation work is subjected to a strong pressing force due to the weight of the machine itself or the load from the outside of the machine. On the other hand, it is considered that the prototype machine 93 continued to rotate while the hitting surface 931 near the corner 933 mentioned above was in contact, causing plastic deformation or uneven wear, and the central deformation part H7 was generated on the hitting surface 931. .

However, according to the drilling apparatus of the present invention, each drilling bit is arranged such that the edge of each striking surface on the rotary shaft side is in the vicinity of the rotary shaft of the chuck guide in either the first arrangement mode or the second arrangement mode. By having a configuration in which they are gathered so as to be close to each other, it is possible to excavate even hard rock, and it is possible to suppress the formation of a central protrusion at the center of the deep side of the excavated hole. It is possible to suppress the occurrence of a central deformed portion (that is, deformation and uneven wear of the drilling bit) caused by the formation of the .

That is, when each drilling bit is configured in the first arrangement mode, only one of the striking surfaces is arranged so as to overlap the rotation axis of the chuck guide (hereinafter referred to as "rotational axis overlapping arrangement"). can always overlap the rotation axis and its vicinity. According to this rotating shaft overlapping arrangement, during the rotary excavation work, excavation is carried out in a state in which a portion of the striking surface reliably overlaps and passes through the rotating shaft of the chuck guide and its vicinity at all times. can be excavated at all times, and the concentration of load on the corners is alleviated. As a result, even when excavating hard rock, the formation of the central convex portion is suppressed, and accordingly the occurrence of the central deformed portion is also suppressed.

In the case where each drilling bit is configured in the second arrangement mode, a pair of rotating shafts of the striking surfaces are arranged so that a corner portion is formed on the rotating shaft side of the chuck guide on the striking surface, and the rotating shaft is interposed therebetween. Only the side edge overlaps with the rotation axis, and the tip of the corner is arranged so as not to overlap with the rotation axis. hereinafter referred to as "non-overlapping arrangement of the rotating shafts on the striking surface"), the long edge, not the tip of the corner, can intermittently or substantially continuously pass through the rotating shaft and its vicinity. As a result, the center of the surface to be excavated is excavated by the edge of the chuck guide on the rotating shaft side of the set of striking surfaces facing each other and the striking surfaces along the edges, and the load is concentrated on the striking surfaces. can be distributed over a plurality of (at least two) striking surfaces, and the concentration of load on the corners is also alleviated. Therefore, the occurrence of central deformation is also suppressed.

Also, each drive unit is configured so that one drive unit and the other drive unit can supply different driving forces, and in a first arrangement mode, a drilling bit arranged so that the striking surface overlaps with the rotary shaft, or In the second arrangement mode, a driving unit that supplies the maximum driving force among the driving units to one of the drilling bits whose striking surface overlaps only the rotating shaft side edge with the rotating shaft. In the case of the filling structure, the striking force of the drilling bit, which is arranged overlapping the rotating shaft, can be particularly enhanced.

Due to the above structure, the impact force imparted by all drilling bits is not uniform, and the impact force can be differentiated, so that, for example, when hitting hard rock during rotary excavation work, the maximum driving force is supplied. The drilling bit crushes hard rock, or the first blow causes it to crack and the subsequent blows of other drilling bits break it into small pieces (these effects are hereinafter referred to as "breaking hard rock, etc."). By doing so, it is possible to further enhance the effects of suppressing the formation of a central protrusion and suppressing the occurrence of a central deformed portion during excavation of hard rock.

By the way, in order to improve the impact force of all drilling bits, it is necessary to take measures such as increasing the size of each part (piston, etc.) of the drive unit. However, since the present invention is configured to improve the striking force of at least one of the drilling bits, the size of the entire device is increased and the air consumption of the drive unit is increased. can be minimized.

In addition, as described above, conventional devices such as the drilling device 9 may cause problems such as inability to crush hard rocks due to insufficient striking power when hitting unexpected hard rocks, but the drilling device of the present invention Since hard rock can be dealt with by each drilling bit set in one of the above-mentioned modes, it is possible to deal with both soft layers and hard rock without replacing the equipment. It is possible to omit unnecessary labor and time due to the replacement of .

In addition, when each drilling bit is formed with a ridge striking portion projecting from the striking surface toward the object to be excavated along the outer peripheral edge of the drilling bit when viewed in the direction of the rotation axis of the chuck guide. Since the first impact can be applied to the object to be excavated with the ridge striking portion that concentrates the load along the ridge, the impact force is further improved compared to the impact with a flat striking surface. Even if the object to be excavated is hard rock in an excavation hole, the impact can be used as a trigger to crush the hard rock.

The striking surface of each excavating bit described above is not limited to a single flat surface. A mode such as one including a surface may be used. In addition, the drilling bit having the ridge striking portion is at least one or more of the respective drilling bits, and naturally includes a mode in which all the drilling bits are formed with the ridge striking portion. Each drilling bit may have a drilling portion on its side surface (for example, a portion for drilling the inner wall of the hole), but the drilling portion on the side does not correspond to the striking surface described above.

Further, the first connection portion is a convex portion having a smaller diameter than the outer diameter of the middle portion in the longitudinal direction of the body portion, and in an end view, the convex portion has a recessed curved cutout that does not overlap with the opening of the drive unit housing portion. It is a structure in which a part is formed,
When the second connecting portion has a structure in which a concave portion capable of tightly fitting the first connecting portion is formed in the end surface of the connecting portion with the device main body, the above-described concave portion of the first connecting portion and the second connecting portion The apparatus main body and the chuck guide can be connected with the fitting structure by the projection.

Since the first connecting portion is a projection having a smaller diameter than the outer diameter of the middle portion in the longitudinal direction of the body, it can be fitted into the second connecting portion which is a recess. In addition, in the end view of the first connecting portion, the convex portion is formed with a recessed curved cutout portion that does not overlap with the opening portion of the drive unit storage portion, so that the drive unit storage portion and the guide hole are aligned linearly. , and has a structure that does not hinder the entry and movement of the connecting shaft of the drilling bit.

The second connecting portion is closely integrated with the first connecting portion fitted to the second connecting portion by forming a concave portion into which the first connecting portion can be tightly fitted on the end surface of the connection portion with the device main body. It is possible to disperse the stress (stress concentration is suppressed) in the entire fitting portion against the external force applied in the direction intersecting the longitudinal direction of the drilling rig, thereby suppressing the occurrence of residual fracture accidents.

Further, in the case where the contact portion between the first connection portion and the second connection portion is provided with the anti-rotation structure, the contact portion where the first connection portion and the second connection portion contact during rotary excavation work , so that mutual sliding rotations do not occur. As a result, the structural rigidity against the shear stress generated at the seam between the apparatus main body and the chuck guide is improved, and the occurrence of residual fracture accidents between the apparatus main body and the chuck guide can be suppressed.

The abutting portion between the first connecting portion and the second connecting portion may be, for example, a combination of the tip surface of the first connecting portion and the bottom surface of the second connecting portion, but is not limited to this. It may be a combination of the side surface of the first connecting portion and the inner side surface of the second connecting portion. Further, as the anti-rotation structure, for example, there is a structure consisting of a rotation-preventing shaft or pin provided in the first connecting portion and a receiving hole for the anti-rotating shaft formed in the second connecting portion. It is not particularly limited as long as it has a suitable structure.

Further, at the connection point between the apparatus main body and the air tank, a third connecting portion, which is either a convex portion or a concave portion, is formed on the other end side of the barrel portion, and the tank barrel portion is fitted with the third connecting portion. In the case where the fourth connecting portion that is connected by the mating structure is formed, and a detachment suppressing structure that suppresses detachment of the third connecting portion and the fourth connecting portion that are in the mated state is provided, the above-described third connecting portion and The fitting structure of the fourth connecting portion enables connection between the air tank and the device main body.

The device body can be connected to the fourth connecting portion formed on the air tank by forming the third connecting portion, which is either a convex portion or a concave portion, on the other end side of the trunk portion. As a result, the device body and the air tank can be connected in a fitted state, and the device body and the air tank that are connected in a fitted state are integrated and reinforced at the joint, thereby improving the shear strength. Therefore, it is possible to suppress the occurrence of residual fracture accident due to the connection portion, which is seen in the conventional device.

Further, since the fourth connection portion is formed on the tank body, the air tank can be connected to the third connection portion of the apparatus main body in a fitted state as described above, thereby integrally connecting with the apparatus main body. can be connected so that it rotates

Furthermore, the detachment prevention structure described above can prevent the air tank and the device main body from being detached (separated) from each other. Further, as the detachment restraint structure, for example, a locking pin penetrating the third connecting portion and the fourth connecting portion, a screwing structure of the third connecting portion and the fourth connecting portion, etc. may be mentioned, but it is limited to this. Instead, it may be another known structure or means capable of suppressing detachment between members.

Note that the third connection portion and the fourth connection portion are, for example, when the third connection portion is a protrusion, the fourth connection portion is a recess, but the present invention is not limited to this. , the fourth connecting portion may be a convex portion. Moreover, the fitting structure may be such that a plurality of projections and recesses are provided in each of the third connection portion and the fourth connection portion.

In addition, the third connecting portion is a convex portion having a diameter smaller than the outer diameter of the intermediate portion in the longitudinal direction of the body, and has a structure in which a male screw is threaded on the side surface of the convex portion. 3 In the case of a structure in which the opening end of the tank body has an inner diameter that allows the connection portion to be tightly fitted, and a female screw is threaded on the inner surface near the opening end, the third connection portion and the fourth connection portion The apparatus main body and the air tank can be connected with the above-described fitting structure of the concave portion and the convex portion.

Since the third connecting portion is a projection having a smaller diameter than the outer diameter of the intermediate portion in the longitudinal direction of the body, it can be fitted into the fourth connecting portion, which is a recess. Moreover, since the third connecting portion has a structure in which a male thread is threaded on the side surface of the convex portion, it can be screwed into the female thread that is threaded on the fourth connecting portion. In other words, although the detachment prevention structure has a simple configuration consisting of a combination of male and female threads, it is possible to firmly connect the air tank and the device body so that they do not detach, and workability during assembly or disassembly is improved. Also good.

The fourth connection portion is an open end of the tank body having an inner diameter that allows the third connection portion to be closely fitted, so that the fourth connection portion is closely integrated with the third connection portion fitted to the fourth connection portion, and the drilling device is extended along the length of the excavator. With respect to the external force applied in the direction crossing the direction and the shear force generated in the twisting direction, the stress can be dispersed (stress concentration can be suppressed) over the entire fitting portion, and the occurrence of residual fracture accidents can be suppressed. Since the structure does not require connection bolts for connecting the air tank and the apparatus main body, there is no possibility of the above-mentioned breakage remaining accident caused by the connection bolts.

In order to achieve the above objects, a rotary excavator of the present invention is provided rotatably about a rotation axis, and has a plurality of drive unit storage sections provided parallel to the rotation axis, and a drive unit storage section. The main body of the device includes a body portion having a substantially solid structure except for the portion, and a first connection portion formed on one end side, and a drive unit that uses air as a power source and is arranged for each drive unit storage portion. , a chuck guide having a second connecting portion that is connected to the first connecting portion with a fitting structure, and a plurality of guide holes that are through holes that are linearly communicated with the drive unit storage portion; A plurality of excavation bits, including a head portion including a connecting shaft portion that is inserted into and axially moved forward and backward upon receiving a driving force from the drive unit, and a striking surface provided at the tip of the connecting shaft portion; an air tank connected to the other end side of the unit and including a tank body capable of feeding air to each drive unit, and an air introduction part capable of introducing air supplied from the outside into the tank body; A drilling device having an air distribution part capable of distributing air supplied from an air tank to a drive unit so that part or all of each drilling bit advances and retreats at different timings, and a rotation that imparts rotational force to the drilling device and a driving device.

Here, in the rotary excavator of the present invention, the main body of the excavator is rotatable around the rotation axis, so that when a rotational force is applied by the rotary drive device, the rotary excavator rotates around the rotation axis. and can perform rotary drilling operations with multiple drill bits.

The main body of the apparatus can store each drive unit by forming a plurality of drive unit storage sections in the body. In addition, since the drive unit storage section is provided in parallel with the rotation shaft, the drive force from the drive unit is transmitted linearly to the excavation bit, and the loss of power transmission can be reduced.

The drive unit storage section is arranged in parallel with the rotation axis so that it is arranged around the rotation axis. It is possible to suppress unnecessary expansion of the excavated hole due to vibration caused by shaft vibration and shaft vibration.

Furthermore, unlike the conventional device, the body is not a hollow cylinder, but a substantially solid column except for the drive unit storage section. , the impact force against the excavated object is improved. In addition, due to the substantially solid structure, the rigidity is higher than that of the conventional device, and breakage due to the body is less likely to occur, so that the service life can be extended.

Since the first connecting portion is formed on one end side, the body portion can be connected to the second connecting portion formed on the chuck guide. As a result, the device body and chuck guide can be connected in a fitted state, and the device body and chuck guide that are connected in a fitted state are integrated and reinforced at the joint, thereby improving the shear strength. Therefore, it is possible to suppress the occurrence of residual fracture accident due to the connection portion, which was seen in the conventional device.

The main body of the device has a drive unit that uses air as a power source, so that the device has good operability and does not generate waste such as liquid working fluid, which is a power source, and exhaust gas, reducing the environmental load. be able to. Further, in the main body of the apparatus, a drive unit is arranged for each drive unit storage section, that is, a plurality of drive units supply driving force to each drilling bit in a corresponding arrangement, thereby performing the drilling operation using a plurality of drilling bits. It can be performed.

In addition, since the drive units are arranged for each drive unit storage section, multiple drive units can be arranged around the rotating shaft in a well-balanced manner, reducing vibration caused by shaft shake during rotary excavation work. can be suppressed.

Since the chuck guide is formed with the second connecting portion, the drilling device can be connected to the first connecting portion of the device main body in a fitted state as described above. Can be connected to rotate.

Since the chuck guide is formed with a plurality of guide holes, a drilling bit can be attached to each guide hole. Furthermore, since each guide hole is a through hole that communicates linearly with the drive unit storage section, the connecting shaft section of the drilling bit can be inserted so as to move forward and backward in the axial direction, and the drive unit can be moved forward and backward. can be transmitted linearly to the drill bit.

Since each drilling bit has a connecting shaft portion, the drilling device can be fitted into each guide hole of the chuck guide and attached to the chuck guide. Since the connecting shaft portion of the excavating bit is inserted into the guide hole, the driving force from the drive unit is transmitted to the base end of the connecting shaft portion, and the driving force is received so that the connecting shaft portion moves along the guide hole. As a result, the drilling bit as a whole, including the head portion, also moves forward and backward.

As a result, the drilling bit hits the object to be excavated in front of the excavator with the striking surface of the head portion, so that the object to be excavated can be excavated. Further, each drilling bit can be independently advanced and retracted by having the connecting shaft portion individually fitted into the guide hole.

As described above, each drilling bit fitted into each guide hole of the chuck guide is arranged around the rotary shaft of the chuck guide. During operation, each drilling bit hits the object to be excavated multiple times, and the object to be excavated can be evenly excavated.

The excavator can introduce air into the body of the tank because the air tank has the air introduction portion. Further, the air tank can be connected to the apparatus body by connecting the tank body to the other end side of the body of the apparatus body, thereby rotating integrally with the apparatus body. can be connected to The air tank connected to the main body of the apparatus can supply the air introduced into the body of the tank to each drive unit.

Since the drilling rig includes the air distribution section, it is possible to distribute the air supplied to the drive unit so that the drilling bits strike at different timings, so that each drilling bit alternately hits the object to be excavated. Since the drill bit hits the object to be excavated at the same time, it is difficult for the drill bits to strike the object at the same time, so that the excavation work can be performed with less vibration and less noise than a conventional down-the-hole hammer.

Further, since the rotary excavator of the present invention is provided with the above-described rotary drive device, it is possible to rotate the drilling device in combination with the rotary drive device. An excavation method can be implemented in which an impact force is applied to the excavated material.

According to the excavator and the rotary excavator of the present invention, the impact force can be improved as compared with the conventional apparatus, and the occurrence of accidents of remaining fractures in the excavated hole during excavation work can be suppressed.

It is a front view which shows the rotary excavator of this invention. 1. It is sectional view explanatory drawing which disassembles and shows the excavator (1st Embodiment) shown in FIG. 1 for every component. FIG. 2 is an explanatory cross-sectional view showing a longitudinal cross section of the entire drilling device shown in FIG. 1 and partially enlarging a connection structure between the device main body and the chuck guide. 4A is a perspective view showing the connection structure between the apparatus main body and the chuck guide shown in FIG. 3, where (a) is a perspective view showing the lower surface of the apparatus main body, and (b) is a perspective view showing the upper surface of the chuck guide. be. Fig. 2 shows the arrangement of the striking surfaces of the drilling bit of the drilling rig, where (a) is a bottom view of the first embodiment, and (b) is a bottom view of another mode (modification 1) of the drilling bit shown in (a). is. Fig. 2 shows the arrangement of the striking surface of the drilling bit of the drilling rig (second embodiment), (a) is a bottom view of the second embodiment, and (b) is another aspect (deformation) of the drilling bit shown in (a). It is a bottom view of example 2). Fig. 12 shows the arrangement of the striking surface of the drilling bit of the drilling rig (third embodiment), (a) is a bottom view of the third embodiment, and (b) is another aspect (deformation) of the drilling bit shown in (a). FIG. 8C is a bottom view of Example 3), and FIG. 8C is a bottom view of another embodiment (Modification 4) of the excavating bit shown in FIG. FIG. 10 shows a drilling bit of a drilling rig (fourth embodiment), (a) is an explanatory side view of an enlarged main part, and (b) is a bottom view showing the layout of the striking surface of the drilling bit shown in (a). , (c) is a bottom view of another embodiment (modification 5) of the excavating bit shown in (a). It is an excavator (fifth embodiment), showing a vertical cross section of the entire excavator, and is an explanatory cross-sectional view showing a partially enlarged connection structure between an air tank and an apparatus main body. FIG. 10 is an explanatory view showing a connection structure between the air tank and the apparatus main body shown in FIG. 9; It is a perspective view which shows the excavator of patent document 1 description. (a) is a perspective view showing the prototype of the excavator before the present invention, (b) is an explanatory diagram comparing the excavation bit before and after the excavation work of the prototype shown in (a), and (c) is shown in (a). It is explanatory drawing which shows the inside of the excavation hole excavated by the prototype machine shown.

Embodiments of the present invention are described in further detail with reference to FIGS. 1-10. The following description will be given in the order of [first embodiment] to [fifth embodiment]. In addition, the reference numerals in each figure of the drawings are attached within the scope of reducing complexity and facilitating understanding. .

A rotary excavator 1 shown in FIG. Each part is described in detail below.

[First embodiment]
(drilling equipment)
Please refer to FIGS. 1-5(a). The drilling device 2 includes an air tank 21 , a device main body 22 , a chuck guide 25 , a plurality of drilling bits 26 and an air distributor 27 .

(device body)
The apparatus main body 22 has a structure having three drive units 220 and a trunk section 221 that houses each drive unit 220 . The trunk portion 221 is provided with a third connection portion 222 on one end surface (the upper end portion in FIG. 2 etc.) and a first connection portion 223 on the other end surface (the lower end portion in FIG. 2 etc.). ing.

A drive unit housing portion 224 is provided in the body portion 221 . The drive unit storage section 224 is a through hole arranged parallel to the rotation axis of the device main body 22. Three drive unit storage sections 224 are provided at equal intervals. It is formed In addition, the drive unit storage section 224 is configured such that the drive unit 220 can be inserted through an opening on the lower end face in FIG. 2 and the like.

Since the drive unit storage part 224 is provided in parallel with the rotation shaft, the drive force from the drive unit 220 is linearly transmitted to the excavation bit 26, and the loss of transmitted power is small. In addition, since the drive unit storage section 224 is provided around the rotation axis and in parallel with the rotation axis, when the rotation drive device 3 is used to apply a rotary motion to the entire excavator 2, vibration due to shaft shake may occur. Also, unnecessary expansion of the excavated hole due to shaft vibration is suppressed.

The body portion 221 is a cylindrical body made of metal, and the portion other than the drive unit storage portion 224 has a substantially solid structure (see FIG. 2-3). By adopting this structure, the excavator 2 has a larger weight (approximately twice the weight of the conventional device) compared to the conventional device (the body is a hollow cylinder) even though the volume is the same. It has improved striking power against excavated objects. In addition, since the trunk portion 221 has a substantially solid structure, it has high rigidity and is hardly deformed by an external force, so that the service life can be extended.

Furthermore, a surface material (not shown) made of a high-strength steel plate is attached to the surface of the body portion 221 . By having this surface material, the body part 221 itself is treated so as not to be worn, and when the surface material is worn or damaged, the surface material can be replaced or repaired to recover the wear resistance. be able to.

The first connecting portion 223 is provided on the other end surface of the body portion 22 (lower end of the body portion 22 in FIG. 2, etc.), and can connect the apparatus main body 22 and the chuck guide 25 with this. A connection bolt 251 is used to connect the device main body 22 and the chuck guide 25 .

The third connecting portion 222 is provided at one end of the trunk (the upper end of the trunk 22 in FIG. 2 and the like). In the present embodiment, the third connecting portion 222 is a flat surface, and with this, the lower surface of the fourth connecting portion 212 of the air tank 21, which is also a flat surface, is brought into contact without gaps to connect the air tank 21 and the apparatus main body 22. can do.

In this embodiment, the first connecting portion 223 is a disk-shaped convex portion having a diameter smaller than the outer diameter of the middle portion in the longitudinal direction of the body portion 221, and is recessed along the extension direction of the guide hole 250 of the chuck guide 25, which will be described later. It is configured in a curved notched shape (substantially trifurcated when viewed from the end face direction). The chuck guide 25 has a structure in which a second connecting portion 252 formed of a concave portion in which the first connecting portion 223 is just accommodated is provided on its upper surface (the end surface facing the apparatus main body 22).

By having this structure, the first connection portion 223 and the second connection portion 252 are connected with a fitting structure using unevenness, and the first connection portion 223 enters and integrates with the second connection portion 252 , so that the excavator 2 is integrated. It is possible to disperse the stress over the entire fitting portion (in other words, suppress the concentration of stress at a specific location) against the external force applied in the direction that intersects the longitudinal direction, thereby suppressing the occurrence of residual fracture accidents. .

The convex portion of the first connecting portion 223 has a concave curved surface along the extension direction of the guide hole 250 at the portion that would normally overlap the guide hole 250 , and has a shape along the edge of the guide hole 250 . Therefore, the forward and backward movement of the connecting shaft portion 260 of the drilling bit is not hindered.

Furthermore, the anti-rotation structure 4 is provided on the abutment surface where the first connection portion 223 and the second connection portion 252 abut. The anti-rotation structure 4 includes first fitting holes 41 (three in total) provided in the first connecting portion 223 and second fitting holes provided in the second connecting portion 252 at positions corresponding to the first fitting holes 41. 42 (three places in total) are formed, and a detent shaft 43 having a length and a thickness that can be just fitted in both mutually aligned holes is fitted.

By having the anti-rotation structure 4 , it is possible to prevent the first connection portion 223 and the second connection portion 252 from sliding against each other on the contact surfaces during the rotary excavation work of the excavator 2 . As a result, the structural rigidity against the shear stress generated at the seam between the device main body 22 and the chuck guide 25 is improved compared to the structure in which the connection bolt 251 is connected alone, and the fracture remains between the device main body 22 and the chuck guide 25. Accident occurrence can be suppressed.

The drive unit 220 has a structure capable of supplying a driving force using air as a power source, and adopts a piston structure in this embodiment. The drive unit 220 has substantially the same structure as a known down-the-hole hammer drive mechanism (for example, described in JP-A-61-92288), and includes a cylinder, piston, check valve, air distributor, valve spring, makeup ring, It is a structure having an O-ring, a piston retainer ring, a bit retainer ring (reference numerals omitted), and the like.

Briefly explaining the operation of the drive unit 220, the air that has flowed into the drive unit 220 first passes through the side of the piston and flows toward the drilling bit (lower side of the drive unit 220 in FIG. 2), and the piston moves toward the air tank. Move to Next, as the piston moves, air flows toward the air tank side of the piston, and air is discharged from the air inlet 263 of the connecting shaft portion 260 of the drilling bit 26 to be described later to the opening air outlet 264 of the striking surface 262. This causes the piston to move from the air tank side to the drilling bit side.

By repeating this action, the piston advances and retreats, and when the piston moves toward the drilling bit, an impact force (corresponding to the aforementioned driving force) is applied to the drilling bit 26, and the drilling bit 26 is driven by this impact force. Further, the drive unit 4 is set so that the timing of inflow of air is adjusted by the air distributor 27 so that the pistons advance and retreat at different timings.

(chuck guide)
The chuck guide 25 has a substantially circular shape in plan view with a notch formed on the side to be excavated and has a predetermined thickness, and a plurality of guide holes 250 are formed along the notch. The chuck guide 25 is connected to the device main body 22 using fasteners consisting of connection bolts 251 and nuts (reference numerals omitted). Since the chuck guide 25 is connected to the device main body 22 as described above, it rotates integrally with the device main body 22 when the device main body 22 rotates.

As described above, the upper surface of the chuck guide 25 is provided with a recessed portion that exactly accommodates the first connection portion 223 , and this portion constitutes the second connection portion 252 . The second connection portion 252 has a shape corresponding to that of the first connection portion 223 (substantially three-pronged recess when viewed from the end face direction), overlaps the rotation axis of the chuck guide 25, and is partly formed by the holes of the guide holes 250. formed along the edges. When the second connecting portion 252 is fitted with the first connecting portion 223, the outer peripheral surface (side surface and lower end surface) of the first connecting portion 223 and the inner peripheral surface (side surface and bottom surface) of the second connecting portion 252 are aligned. It has a structure in which they are in close contact with each other with almost no gap.

The guide holes 250 are through holes formed around the rotating shaft of the chuck guide 25 in parallel with the rotating shaft and communicating with the drive unit housing portion 224 in the same axial direction. It is formed in such a size that a connection shaft portion 260 of the excavation bit 26, which will be described later, can be slidably accommodated.

The guide hole 250 has a hexagonal inner diameter portion with a predetermined length extending from the opening in the lower end face in FIG. 260 can be inserted, and the connection shaft portion 260 can advance and retreat along the guide hole 250 in the inserted state.

That is, the chuck guide 25 can attach the drilling bit 26 through each guide hole 250, and the driving force from the drive unit 220 stored in the drive unit storage part 224 at the position communicating with the guide hole 250 is applied to the chuck guide 25 for drilling. Bit 26 can be conveyed.

At the opening edge of the guide hole 250 on the side where the second connection portion 252 is formed, a groove-shaped recess 253 is formed that extends along the outer edge portion. A rubber ring 254 slightly larger than the diameter is press-fitted (see the enlarged portion of FIG. 3 and FIG. 4(b)) to suppress rattling and provide a cushioning effect.

(drilling bit)
Please refer to FIGS. 2, 4 and 5(a). The excavation bit 26 has a connecting shaft portion 260 and a head portion 261 provided at the lower end portion of the connecting shaft portion 260 (opposite direction to the drive unit 220) in FIG. 2 and the like, a hitting surface 262 is provided at the lower end portion of the head portion 261 (opposite direction to the connecting shaft portion 260), and an air discharge port 264 is formed substantially in the center.

The connection shaft portion 260 is a portion that receives the driving force from the drive unit 220, and has a substantially cylindrical outer shape that can be inserted into the guide hole 250. The tip is a free end with an air inlet 263 formed therein. , the proximal end is fixed to the upper portion of the head portion 261 . In addition, the flow path in the connection shaft portion 260 and the flow path formed in the head portion 261 communicate with each other to form an air flow path 265 . The air flow path 265 has an air inlet 263 as a starting point and an air outlet 264 as an end point, and a check valve (not shown) is provided in the flow path to prevent backflow of air toward the head portion 261 . .

More specifically, the connecting shaft portion 260 has a hexagonal outer peripheral surface from the axial center to the head portion 261 side in a cross-sectional view. , and the forward and backward movement of the connection shaft portion 260 is not hindered. Further, the connection shaft portion 260 is mounted so as not to come off from the guide hole 250 by the hammer bit retainer ring and the O-ring described above.

The head portion 261 has a substantially pentagonal prism shape, and the striking surface 262 also has a substantially pentagonal shape. The striking surface 262 has an arcuate portion along a portion of the outer circumference of the excavator 2 in a bottom view in a state of being attached to the chuck guide 25 (hereinafter simply referred to as "attached state" in this paragraph). , and a corner portion 267 having an obtuse angle (approximately 120°) at the tip is provided in the opposite direction of the arc-shaped portion (that is, toward the rotating shaft of the excavator 2). The corner portion 267 has the same length on both sides sandwiching the same corner portion (equilateral).

In the head portion 261, button-shaped cemented carbide chips (reference numerals omitted) are implanted at predetermined intervals in the entire hitting surface 262 and in a portion of the sidewall rising from the hitting surface 262 near the hitting surface. (distributed arrangement).

The air discharge port 264 is formed substantially in the center of the striking surface 262, and the air passing through the air flow path 265 is discharged from here. Also, the air discharge port 264 is formed with two exhaust guide grooves 266 extending from the rim of the air discharge port 264 toward the side edges of the striking surface 262 . The exhaust guide groove 266 guides the air discharged from the air discharge port 264 in the excavated hole H1 toward the outer surface of the excavator 2 between the hole bottom surface H3 and efficiently diffuses the air in the hole. Discharge of soil can be promoted.

In the drilling bit 26 configured as described above, the connecting shaft portion 260 advances and retreats along the guide hole 250, and the entire drilling bit 26 including the head portion 261 also advances and retreats accordingly. The object to be excavated ahead of the device 2 is hit to perform excavation.

The three excavation bits 26 are arranged around the rotation shaft 2R of the device main body so that the corners 267 are butted against each other. . In this embodiment, each excavation bit 26 is arranged such that the tips of the corners 267 are close to each other in the vicinity of the rotation axis 2R and none of the corners 267 overlaps the rotation axis 2R (hereinafter referred to as "rotational axis non-overlapping arrangement"). It has become.

In the drilling device 2, the drilling bits 26 are arranged in the above-described configuration, so that the striking surfaces 262 of the drilling bits 26 are closely gathered in the vicinity of the rotating shaft 2R of the device main body. , there is no extra gap around the rotating shaft 2R. According to this configuration, by performing the excavation work while rotating the excavator 2, the object to be excavated that is hit by each excavation bit 26 can be excavated evenly.

Since each drilling bit 26 has the same structure, there is no need to manufacture, purchase, or store two types of drilling bits like the drilling bits 26b1 to 26f2 described later, and only one type of drilling bit can be procured. As a result, for example, when used as a replacement part or a spare part, even if any drilling bit is lost, only one type of drilling bit needs to be prepared. In addition, space can be saved during storage, and the number of replacement parts and the like to be brought to the site can be reduced.

(air tank)
The air tank 21 is connected to the other end side of the device main body 22, and is arranged so as to be above the drilling rig 2 in FIG. (See Figure 1-4). A connection bolt 219 is used to connect the air tank 21 and the device main body 22 . Since the air tank 21 is connected to the device main body 22 as described above, it rotates integrally with the device main body 22 when the device main body 22 rotates.

The air tank 21 temporarily stores high-pressure air introduced from an air supply source such as an external compressor (not shown) and supplies it to the apparatus main body 22. shaped tank body 210, an air introduction part 211 provided on the lid on one end side (upper side in FIG. 2 etc.) of the tank body 210, provided on the other end side (lower side in FIG. 2 etc.) of the tank body 210 It has a fourth connection portion 212 provided with the tank body 210 and a spiral blade 213 provided on the side surface of the tank body portion 210 .

In this embodiment, the air tank 21 has a structure in which a detachable cylindrical attachment (reference numerals omitted) is fitted onto the outside, and the spiral blade 213 appearing on the side surface of the air tank 21 in FIG. 1 etc. is provided on the attachment. However, it is not limited to this. For example, instead of the spiral blade 213, a flat bar or the like extending in the longitudinal direction of the device may be provided, or the spiral blade may be directly attached to the surface of the air tank 3 without using an attachment. It may be provided.

Since the tank body 210 has a smaller diameter than the device body 22, the maximum diameter portion 21M of the tank body 210 and the maximum diameter portion 22M of the device body 22 are the same or the tank body 210 has a slightly larger diameter. (hereinafter referred to as “substantially the same”) (see FIG. 4, etc.). The soil is lifted up via the spiral blades and discharged without increasing the hole diameter of the hole H1. The tank body 30 has an airtight structure, and can temporarily store air supplied from the outside in a high pressure state.

The air introduction part 211 is a hexagonal prism-shaped connecting joint whose rotation axis coincides with the rotation axis of the air tank 21 , and the base end is attached to the air tank 21 . The air introduction portion 211 has an opening 214 with a free end, and a flow path 215 communicating with the air tank 21 from the opening 214 is formed (see FIG. 2). The air introduction portion 211 rotatably connects the air tank 21 and a suspension shaft 34 to be described later. Air is supplied to (see FIG. 1-3).

The fourth connection portion 212 has a required thickness, and is formed with insertion holes 218 (three in total) into which respective ends of the drive unit 220 are inserted (see FIG. 2). The fitting hole 218 communicates with a drive unit housing portion 224 of the apparatus main body 22, which will be described later, and has a shape in which the upper region in FIG. , and the tip portion opens into the tank body 210 of the air tank 21 . This opening serves as an air lead-out hole 226 through which air can be led out to the drive unit housing portion 224 .

A welded portion 217 is formed by welding on the outer surface of the connecting portion between the lower end of the tank body portion 210 and the upper end of the fourth connecting portion 212 . This welded portion 217 improves wear resistance, rigidity against shear stress, and locking force at the connecting portion between the lower end of the tank body portion 210 and the upper end of the fourth connecting portion 212 .

(Air distributor)
The air distribution portion 27 is arranged on the upper surface of the fourth connection portion 212 inside the air tank 21 and has an air receiving portion 270 and a support base portion 271 . The air receiving portion 270 has a flat plate shape and a concave curved surface is formed on the upper portion thereof. The support base portion 271 has a cylindrical shape, supports the lower surface of the air receiving portion 270 at its upper end, and is fixed to the upper surface of the fourth connecting portion 212 at its lower end. The air distribution portion 27 controls the flow direction of air supplied through the air introduction portion 211 in the air tank 21 .

Specifically, first, the air receiving portion 270 directly receives the air supplied from the direction of the air introducing portion 211, and then the air hits the air receiving portion 270, changes its direction of flow, and swirls within the air tank 21, turning The flow of the air is controlled by flowing the air into the air lead-out hole 226 of the device main body 22 at different timings. By changing the flow of air in the air tank 21 in this way, the arrival time of air from the air tank 21 to the drive unit 220 is also changed, and the pistons of the drive unit 220 advance and retreat at different timings.

(rotation drive device)
In the present embodiment, the rotary drive device 3 includes a body portion 30 having a rotary table 31 formed with an insertion hole 311 penetrating in the vertical direction, and a support leg 32 having an outrigger structure for supporting the body portion 30. . The rotary table 31 has a driving portion (not shown) composed of a hydraulic motor, a gear device, and the like. An inner wall of the insertion hole 311 of the rotary table 31 is formed with a locking projection (not shown) extending along the central axis of the insertion hole 311 .

The rotation drive device 3 has the above-described configuration, so that when the drilling device 2 is passed through the insertion hole 311 of the rotary table 31, the locking projection provided in the device and the spiral blade 213 of the drilling device 2 are aligned. The locking recesses (reference numerals omitted) formed in are slidably locked, whereby the drilling device 2 attached to the rotary drive device 3 can be lowered by its own weight. Since the locking projection and the locking recess are in the locked state, the driving force from the rotary drive device 3 is applied to the excavator 2, and the excavator 2 can be driven to rotate in the horizontal direction. Note that the rotary drive device 3 has a known structure as disclosed in, for example, Japanese Patent Application Laid-Open No. 2011-26955, so the description of the structure and action is limited to the above-mentioned outline description, and the details are omitted.

[Modification 1]
Please refer to FIG. A drilling rig 2a shown in the figure is another aspect (modification 1) of the drilling rig 2, and differences will be described based on the drawings. Except for differences described later, the structure and effects of each part are substantially the same as those of the drilling rig 2, and thus the description thereof will be omitted.

The excavator 2a has four excavation bits 26a of the same shape. When viewed from the bottom, the drilling bit 26a has a corner portion 267a formed at a right angle (approximately 90°) and both sides sandwiching the corner portion 267a have the same length (equilateral). As a result, the striking surfaces 262a of the drilling bits 26a are arranged in a substantially cross shape with equal intervals in the circumferential direction in a bottom view.

Along with this difference, portions corresponding to the number of drilling bits 26a (drive unit storage portion 224 of body portion 221 of device main body 22, drive unit 220, air outlet hole 226, guide hole 250 of chuck guide 25) ) are also configured to be four each.

[Second embodiment]
Please refer to FIG. A drilling rig 2b shown in the figure is another aspect (second embodiment) of the drilling rig 2, and differences will be described based on the drawings. Except for differences described later, the structure and effects of each part are substantially the same as those of the drilling rig 2, and thus the description thereof will be omitted.

The drilling rig 2b is formed by combining two sets of drilling bits 26b1 and 26b2 having different shapes (four in total), and is a mode in which the second arrangement mode described above is applied to the arrangement of the striking surfaces. The drilling bits 26b1 and 26b2 have striking surfaces 262b1 (striking surface of the drilling bit 26b1) and 262b2 (striking surface of the drilling bit 26b2) arranged around the rotating shaft 2R of the device body, and the drilling bits of the same shape are arranged. are not adjacent to each other (that is, the drilling bits 26b1 are not adjacent to each other, and the drilling bits 26b2 are not adjacent to each other).

The drilling bit 26b1 has a corner portion 267b1 on the striking surface 262b1, and the corner portion 267b1 has different lengths on both sides sandwiching the same corner portion (unequal sides). The drilling bit 26b2 has a corner portion 267b2 on the striking surface 262b2, and the corner portion 267b2 has the same length on both sides sandwiching the same corner portion (equilateral). The excavation bits 26b1 and 26b2 are collectively arranged so that the corners 267b1 and 267b2 face the direction of the rotation axis 2R of the apparatus main body and are close to each other in the vicinity of the rotation axis 2R so that there is no gap.

Each excavation bit 26b1 is arranged to face the rotation axis 2R of the device body, only the long side of the corner portion 267b1 overlaps the rotation axis 2R of the device body, and the tip of the corner portion 267b1 is the rotation axis of the device body. It is arranged so as not to overlap with 2R. Further, the drilling bits 26b2 are arranged to face each other across the rotation axis 2R of the device main body between the drilling bits 26b1, and are arranged so that the tip and both sides of the corner portion 267b2 do not overlap the rotation shaft 2R of the device main body. ing.

According to the drilling bits 26b1 and 26b2 arranged in the second arrangement mode, the striking surfaces 262b1 and 262b2 are attached to the rotating shaft 2R of the device main body and its vicinity with almost no gap. According to this configuration, the object to be excavated H hit by the excavation bits 26b1 and 26b2 is excavated evenly, and the excavation hole H1 formed by the excavation work is substantially flat without forming a central protrusion on the inner bottom. become something.

Further, the excavation bits 26b1 and 26b2, which are arranged so that the rotation axis does not overlap, intermittently or substantially continuously rotate the rotation axis 2R of the apparatus main body and the vicinity thereof at the long edges sandwiching the corner 267b1 during rotary excavation work. It passes through and excavates with the striking surfaces 262b1 and 262b2 of the long edge portion and the portion along the long edge portion. As a result, the load concentrated on the striking surface near the rotary shaft 2R of the device main body is dispersed at a plurality of locations (two locations in this embodiment), and the concentration of the load on a small number of chips at the corners is also alleviated. Also during excavation of hard rock, the formation of the central convex portion H6 is suppressed, and along with this, the occurrence of the central deformed portion H7 is also suppressed.

The drilling bits 26b1 and 26b2 have different shapes and sizes of striking surfaces (the drilling bit 26b2 is smaller than the drilling bit 26b1). Only the long side portion of the drilling bit 26b2 is arranged close to the rotary shaft 2R of the device main body, while neither of the two sides of the corner portion 267b2 and the same corner portion of the drilling bit 26b2 are arranged close to the rotary shaft 2R of the device main body ( In other words, it is arranged apart from the rotating shaft 2R of the apparatus main body).

The excavation bits 26b1 and 26b2 are arranged at positions where the tips of the corners are about 6% of the distance from the rotation axis 2R of the device main body to the outer peripheral end of the body 221, with the rotation axis 2R of the device main body as a reference. is set to

[Modification 2]
See FIG. 6(b). A drilling rig 2c shown in the figure is another aspect (modification 2) of the drilling rig 2b, and differences will be described based on the drawings. Except for differences described later, the structure and effects of each part are substantially the same as those of the drilling rig 2b, and thus the description thereof is omitted. Further, in Modification 2, the number of portions corresponding to the number of drilling bits (the drive unit storage portion, the drive unit, the air introduction hole, and the guide hole in the chuck guide 25) is three each. ing.

The excavator 2c is formed by combining two sets of excavating bits 26c1 and 26c2 (three in total) having different shapes, and is a mode in which the first arrangement mode described above is applied to the arrangement of the striking surfaces. The drilling bits 26c1 and 26c2 have striking surfaces 262c1 (striking surface of the drilling bit 26c1) and 262c2 (striking surface of the drilling bit 26c2) arranged around the rotary shaft 2R of the device body, and the striking surface of each drilling bit is It has a three-pronged arrangement that is evenly spaced in the circumferential direction.

The drilling bit 26c1 has a corner portion 267c1 on the striking surface 262c1, and the corner portion 267c1 has the same length on both sides sandwiching the same corner portion (equilateral). The drilling bit 26c2 has a corner portion 267c2 on the striking surface 262c2, and the corner portion 267c2 has different lengths on both sides sandwiching the same corner portion (unequal sides). The drilling bits 26c1 and 26c2 are collectively arranged such that the corners 267c1 and 267c2 face the direction of the rotation axis 2R of the apparatus main body and are close to each other near the rotation axis 2R so that there is no gap.

The striking surface 262c1 is formed to be slightly larger than the striking surface 262c2, and the tip of the corner portion 267c1 extends beyond the rotating shaft 2R of the device main body (in other words, including the rotating shaft). be. That is, only the corner portion 267c1 overlaps the rotation axis 2R of the apparatus main body, and the corner portion 267c2 is arranged so as not to overlap the rotation axis 2R of the apparatus main body. Each hitting surface 262c2 is arranged such that one side edge of the corner portion 267c2 is adjacent to the diameter line, and the other side edge is adjacent to the corner portion 267c1.

According to the drilling bits 26c1 and 26c2 arranged in the first arrangement mode, the striking surfaces 262c1 and 262c2 are attached to the rotating shaft 2R of the device main body and the vicinity thereof with almost no gap. According to this configuration, the object to be excavated H hit by the excavation bits 26c1 and 26c2 is excavated evenly, and the excavation hole H1 formed by the excavation work is substantially flat without forming a central protrusion on the inner bottom. become something.

Further, the drilling bits 26c1 and 26c2 drill while the striking surface 267c1 of the drilling bit 26c1 always passes through the rotating shaft 2R of the apparatus main body and the vicinity thereof during the rotary drilling operation. As a result, the load concentrated on the striking surface near the rotary shaft 2R of the main body of the device is received by the corner 267c1, which is relatively wide and has a large number of chips, so that the load concentration is alleviated. The formation of the central convex portion H6 is suppressed even at times, and along with this, the occurrence of the central deformation portion H7 is also suppressed.

The tips of the corners of the excavation bits 26c1 and 26c2 are located at positions where they are about 5.4% of the distance from the rotation axis 2R of the device main body to the outer peripheral end of the body 221, with the rotation axis 2R of the device main body as a reference. set to be placed.

[Third embodiment]
Please refer to FIG. A drilling rig 2d shown in the figure is another aspect (a third embodiment) of the drilling rig 2, and differences will be described based on the drawings. Except for differences described later, the structure and effects of each part are substantially the same as those of the drilling rig 2, and thus the description thereof will be omitted.

Like the drilling rig 2b, the drilling rig 2d is formed by combining two sets of drilling bits 26b1 and 26b2 having different shapes (four in total), and is a mode in which the second arrangement mode described above is applied to the arrangement of the striking surfaces. . In the excavator 2d, the four drive units 220a, 220b, 220c, and 220d are arranged to hit the excavation bit whose striking surface overlaps the rotation axis only at the side edge of the rotation axis. It has a structure that gives impact power.

The drive units 220a, 220b, 220c, and 220d are set so that the cylinders have different diameters and the weights of the built-in pistons are different.

Specifically, with the excavation bit 26b1 located on the lower right side of FIG. , and the drive unit 220b that supplies drive to its clockwise circumferentially adjacent drill bit 26b2 has a diameter of 6 inches (152.4 mm) and weighs 23 kg and its clockwise circumferentially adjacent drill bit. The drive unit 220c that supplies drive to 26b1 is 8 inches (203.8 mm) in diameter and weighs 31 kg, and its clockwise circumferentially adjacent drill bit 26b1 is driven by: It has a diameter of 5 inches (127 mm) and a weight of 9.4 kg.

In this way, the drive unit 220a having the largest piston is attached to the largest striking surface (the striking surface 262b1 of the drilling bit 26b1) among the drilling bits 26b1 and 26b2, and the maximum striking force is applied. , during a rotary drilling operation, the drilling bit 26b1 crushes the hard rock H4, or cracks the hard rock H4 so that it can be broken into small pieces by subsequent impacts of other drilling bits 26b1, 26b2.

According to the excavator 2d, the increase in the weight of the entire apparatus and the increase in the consumption of working fluid (air) are suppressed to the necessary minimum, while suppressing the formation of the central convex portion H6 and the occurrence of the central deformation portion H7 during excavation of hard rock. Each effect of suppression can be further enhanced.

[Modification 3]
Refer to FIG. 7(b). A drilling rig 2e shown in the figure is another aspect (modification 3) of the drilling rig 2d, and differences will be described based on the drawings. Except for differences described later, the structure and effects of each part are substantially the same as those of the drilling rig 2d, and thus the description thereof is omitted. Further, in the third modification, as in the first modification, the number of portions corresponding to the number of drilling bits (the drive unit housing portion, the drive unit, the air introduction hole, and the guide hole in the chuck guide 25) is also three. It is configured to be one by one.

Like the drilling rig 2c, the drilling rig 2e is formed by combining two sets of drilling bits 26c1 and 26c2 having different shapes (three in total), and is a mode in which the first arrangement mode described above is applied to the arrangement of the striking surfaces. . The excavator 2e has a structure in which the three drive units 220e, 220f, and 220g apply the maximum striking force among the excavating bits to the excavating bits whose striking surfaces overlap the rotating shafts. ing.

The drive units 220e, 220f, and 220g are set so that the cylinders have different diameters and the weights of the built-in pistons are different.

Specifically, with the excavation bit 26c1 positioned at the bottom center of FIG. , and the drive unit 220f that supplies drive to its clockwise circumferentially adjacent drill bit 26b2 has a diameter of 8 inches (203.8 mm) and weighs 31 kg and its clockwise circumferentially adjacent drill bit. The drive unit 220g that supplies drive power to 26b2 has a diameter of 6 inches (152.4 mm) and a weight of 23 kg.

The excavator 2e also suppresses the formation of the central convex portion H6 and the occurrence of the central deformed portion H7 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 can be further enhanced.

[Modification 4]
Refer to FIG. 7(c). A drilling rig 2f shown in the figure is another aspect (modification 4) of the drilling rig 2d, and differences will be described based on the drawings. Except for differences described later, the structure and effects of each part are substantially the same as those of the drilling rig 2d, and thus the description thereof is omitted. Also in Modification 4, as in Modification 1, the number of portions corresponding to the number of drilling bits (the drive unit storage portion, the drive unit, the air introduction hole, and the guide hole in the chuck guide 25) is two. It is configured to be one by one.

The excavator 2f is formed by combining two sets of excavating bits 26f1 and 26f2 having different shapes (two in total), and is a mode in which the first arrangement mode described above is applied to the arrangement of the striking surfaces. The striking surfaces of the drilling bits 26f1 and 26f2 are substantially semicircular, and the striking surface 262f1 of the drilling bit 26f1 is larger than the striking surface 262f2 of the drilling bit 26f2. The edge portion of the striking surface 262f1 of the excavating bit 26f1 on the side of the rotating shaft 2R of the device main body extends beyond the rotating shaft 2R of the device main body (in other words, including the rotating shaft). be. That is, only the striking surface 262f1 overlaps with the rotation axis 2R of the device main body, and the striking surface 262f2 is arranged so as not to overlap with the rotation axis 2R of the device main body.

In the excavator 2f, the two drive units 220h and 220i are set so that the cylinders have different diameters and the weights of the built-in pistons are different, and the striking surface is arranged so as to overlap the rotation axis. It has a structure that gives the maximum impact force to the drilling bit among the drilling bits.

Specifically, with the excavation bit 26f1 positioned on the lower left side of FIG. , the drive unit 220i, which provides drive to the adjacent drilling bit 26f2, is set to have a diameter of 8 inches (203.8 mm) and a weight of 31 kg.

Although the drilling rig 2f yields to the other drilling rigs described above in terms of quietness and low vibration, it has less vibration and noise than a single-bit down-the-hole hammer, and has a greater impact force than the other drilling rigs. , can be suitably used for excavated objects containing a large amount of hard rock. The excavator 2f also suppresses the formation of the central convex portion H6 and the deformation of the central deformed portion H7 during hard rock excavation, while minimizing an increase in the weight of the entire device and an increase in the consumption of working fluid (air). Each effect of occurrence suppression can be further enhanced.

In this modification, the drive unit of the excavator 2f is set so that the cylinder diameter and the piston weight are different, but this is not restrictive. may be in the same manner.

[Fourth embodiment]
Refer to FIGS. 8(a) and 8(b). A drilling rig 2g shown in the figure is another aspect (fourth embodiment) of the drilling rig 2, and differences will be described based on the drawings. Except for differences described later, the structure and effects of each part are substantially the same as those of the drilling rig 2, and thus the description thereof will be omitted.

The drilling rig 2g differs from the drilling rig 2 in the structure of the drilling bit, and the drilling rig 2g is a combination of four drilling bits 26g. Each excavation bit 26g is formed with a ridge striking portion 268 that protrudes from the striking surface 262g toward the object to be excavated along the outer peripheral edge of the excavation bit 26g as viewed in the rotation axis direction.

The ridge striking portion 268 has an inclined surface formed between it and the flat portion of the striking surface 262g. The projection height of the ridge striking portion 268 is set to 3 cm from the flat portion.

The drilling rig 2g can apply an initial impact to the drilled object with a ridge striker 268 that concentrates the load along the ridge at each drilling bit 26g, thus providing more impact than a flat striking surface. The force is improved, and even if the object to be excavated is hard rock in an excavation hole, the hard rock can be crushed by this impact.

In addition, since the drilling device 2g has the ridge striking portion 268, it is possible to cope with both soft layers and hard rocks without having to replace the equipment. can be omitted. Also, when excavating hard rock, excavation work can be performed with relatively low noise and low vibration. In addition, the ridge striking portion 268 is set to the above-described inclination angle and projection height, so that it has a structure that is resistant to chipping and exhibits excellent durability.

[Modification 5]
See FIG. 8(c). A drilling rig 2h shown in the figure is another aspect (modification 5) of the drilling rig 2g, and differences will be described based on the drawings. Except for differences described later, the structure and effects of each part are substantially the same as those of the drilling rig 2, and thus the description thereof will be omitted.

The excavator 2h has three excavation bits 26h of the same shape, and is arranged in a three-pronged manner at regular intervals in the circumferential direction when viewed from the bottom. Each excavation bit 26h is formed with a ridge striking portion 268 that protrudes from the striking surface 262h toward the object to be excavated along the outer peripheral edge of the excavation bit 26g as viewed in the rotation axis direction. The ridge striking portion 268 has an inclined surface formed between it and the flat portion of the striking surface 262h. The projection height of the ridge striking portion 268 is set to 3 cm from the flat portion.

Due to this difference, the number of portions corresponding to the number of drilling bits 26h (the drive unit housing portion, the drive unit, the air introduction hole, and the guide hole in the chuck guide) is also three. ing.

[Fifth embodiment]
Please refer to FIGS. The drilling rig 2i shown in the figure is another aspect (fifth embodiment) of the drilling rig 2, and the differences will be described based on the drawings. Except for differences described later, the structure and effects of each part are substantially the same as those of the drilling rig 2, and thus the description thereof will be omitted.

The drilling rig 2i has a structure in which a fourth connecting portion 212i of an air tank 21i is an opening having an inner diameter that can accommodate a third connecting portion 222i, which will be described later, and a female screw 216 is provided on the inner surface near the opening. As a result, the fourth connection portion 212i can be fitted with the third connection portion 222i inside thereof, and can be screwed together with a female screw 216 and a male screw 225 provided on the side surface of the third connection portion 222i, which will be described later. can.

The excavator 2i has a shape in which a third connection portion 222i provided on one end surface of a body portion 221i of a device body 22i (the upper end of the body portion 221i in FIG. 2 and the like) is fitted with a fourth connection portion 212i. In addition, the structure includes a detachment restraining structure that restrains detachment of the fourth connecting portion 212i in the connected state. The third connection portion 222i and the fourth connection portion 212i can be connected with a fitting structure, that is, the air tank 21 and the device main body 22 can be connected.

More specifically, the third connecting portion 222i is a substantially cylindrical convex portion having an outer diameter smaller than the outer diameter of the middle portion in the longitudinal direction of the body portion 22i and just fitting into the opening of the fourth connecting portion 212i. It has a structure in which a male screw 225 (a paired part of the detachment restraint structure) is provided on its side surface. As a result, the third connecting portion 222i can be fitted into the fourth connecting portion 212i, and can be screwed using the female thread 216 and the male thread 225. As shown in FIG. The height from the base end to the upper end of the third connection portion 222i is set to about 20 cm.

In the structure described above, when the female screw 216 and the male screw 225 are screwed together, the connected air tank 21i and the apparatus main body 22i are prevented from separating (separating). In addition, compared with the conventional device, the structure does not require connection bolts for connecting the air tank 21i and the device main body 22i, so the possibility of occurrence of fracture residual accidents in the excavated hole is reduced. Moreover, since the fitting structure is a simple structure, workability during assembly or disassembly is good.

Furthermore, according to this fitting structure, the third connecting portion 222i is densely inserted into the fourth connecting portion 212i without any gaps to be integrated, thereby dispersing the stress in the entire fitting portion (in other words, stress applied to a specific portion). By suppressing concentration, the shear strength is improved, and this also reduces the possibility of occurrence of residual fracture accidents.

Further, in the excavator 2i, a welded portion 217 is formed by welding on the outer surface of the connecting portion between the lower end of the air tank 21i and the upper end of the device main body 22i. This welded portion 217 improves wear resistance, rigidity against shearing stress, and locking force at the connecting portion between the lower end of the air tank 21i and the upper end of the device main body 22i.

The excavator 2-2i has two to four drive units 220-220i housed in the device main body 22, but is not limited to this, and may have, for example, five or more. In that case, the number of drive unit housings, the number of excavation bits, etc. may also be appropriately changed to match this number.

The device main body 22 is provided with a flat bar parallel to the longitudinal direction of the outer periphery of the body portion 221, but is not limited to this. Various modifications such as a mode in which spiral blades are provided and a mode in which reinforcing ribs are provided between spiral blades are not excluded.

As an example of the third connecting portion, the apparatus main body 22 has a structure composed of a substantially cylindrical convex portion smaller in diameter than the outer diameter of the middle portion in the longitudinal direction of the trunk portion, but it is not limited to this. Instead, it may be, for example, an elliptical columnar protrusion, a triangular columnar protrusion, a square or other polygonal columnar protrusion, and the shape of the fourth connecting portion of the air tank 21 may also be changed in accordance with the shape of the third connecting portion. . In this case, for the detachment restraint structure, for example, known means such as fixing with a locking pin passing through both the fourth connection portion and the third connection portion may be applied.

In addition, although the third connecting portion 222i has a height of about 20 cm from the base end to the upper end, it is not limited to this. The height is preferably in the range 10 cm-30 cm. If it is less than 10 cm, the fitting part becomes small, and the effect of improving the shear strength by dispersing the stress as a whole cannot be expected much, which is not preferable. This is also not desirable because the tank capacity will be smaller.

Furthermore, the first connecting portion of the device main body 22 and the second connecting portion of the chuck guide 25 may have a structure in which the unevenness is reversed (the first connecting portion is a concave portion and the second connecting portion is a convex portion). And, the shape of the convex portion is not limited to the shape described above, and may be appropriately changed to another shape. Similarly, even if the third connecting portion 222i of the device main body 22 and the fourth connecting portion 212i of the air tank 21 have opposite concave and convex structures (the third connecting portion is a concave portion and the fourth connecting portion is a convex portion). good.

The drilling bits 26-26h have one air discharge port provided on the striking surfaces 262-262h, but this is not a limitation. may be provided two or more. When two or more air discharge ports are provided, it is possible to facilitate the diffusion of excavated debris in the circumferential direction at the bottom of the excavated hole, thereby further promoting the efficiency of earth removal.

Further, the drilling bits 26 to 26h are formed so that the exhaust guide grooves 266 are oriented in different directions from the rim of the air discharge port 264 (the two lines join together around the air discharge port 264, so it can be expressed as one line). However, it is not limited to this. For example, the number of exhaust guide grooves may be one or three or more, and the exhaust guide grooves 266 may be oriented in the same direction. good too.

Furthermore, although the excavation bits 26-26h have chips dispersedly planted on the striking surfaces 262-262h, the present invention is not limited to this. As a result of connecting the flat surface and the recessed portion, the flat surface may be substantially a convex portion and substitute for the function of the chip.

When each drilling bit is arranged in the first arrangement mode or the second arrangement mode, each drilling bit has a tip of a corner portion which is positioned from the rotation axis 2R of the device main body with respect to the rotation axis 2R of the device main body. Although it is set to be arranged at a location that is about 6% of the distance to the outer peripheral end of the body 221, it is not limited to this, for example, the distance is 5% to 30% of the radius area. It is preferably set to fit inside. If it is less than 5%, the corner portion is too close to the rotation axis, and a central convex portion H6 is formed at the center of the deep side of the excavated hole during hard rock excavation, as shown in FIG. 12(c). On the other hand, if it exceeds 30%, there is a possibility that a drilling bit that is smaller than the diameter of the piston member may occur, and there is a risk that the impact force transmission efficiency will decrease. It is also not preferable because there is

The drilling bits 26-26h have striking surfaces 262-262h formed in a pentagonal or substantially semicircular shape, but are not limited to this. It may be rectangular or the like, and when a plurality of drilling bits are attached to the drilling device, the portions of the drilling bits in the direction of the rotation axis 2R of the device body are close to each other in the vicinity of the rotation axis, leaving a gap. It suffices if they are configured so that they are collectively arranged so that they do not overlap. Further, the head portion is not limited to a prism shape, and may be a frustum shape having a bottom surface that serves as a hitting surface.

The ridge striking part 268 provided on the excavation bit has an inclined surface with an inclination angle of 35°, but the inclination angle is not limited to this, and may be, for example, within a range of 20° to 60°. , more preferably 30° to 50°. If the angle of inclination is less than 20°, the entire inclined surface of the striking surface portion becomes too wide and flat as a whole. On the other hand, if the angle of inclination exceeds 60°, the ridge striking portion protrudes too sharply, and the ridge striking portion tends to be chipped when hitting hard rock, which is also undesirable. be.

In addition, the projection striking part 268 has a projection height of 3 cm from the flat portion of the striking surface, but is not limited to this. It is preferably 3 to 5 cm, more preferably 3 to 5 cm. If the protrusion height is less than 2 cm, the protrusion height from the flat portion is low, so it is not preferable because it is difficult to exert a striking force that bites into hard rock. This is because the ridge hitting portion is likely to be chipped when hitting hard rock, which is also not preferable.

Although the illustrated air distribution portion 27 has a cup shape, it is not limited to this. 222, which is rotatably attached along the upper surface of the device body 22 and intermittently closes the air lead-out hole 226 formed in the apparatus main body 22 as it rotates; Designed with a shape or structure that prevents the air in the air tank from flowing into the drive unit at the same timing, such as a structure that changes the inflow timing by dividing the length of the path into long or short, or a structure that opens and closes the air outlet hole intermittently. It is not particularly limited as long as it is specified.

The illustrated rotary drive device 3 is of a mode that imparts a rotational force to the excavating devices 2a-2i so that they can be lowered by their own weight, but is not limited to this. A mode having a mechanism for pushing the excavator toward the object to be excavated may be used. Although the illustrated rotation drive device 3 is provided in a table shape, it is not limited to this. The device is not particularly limited as long as it can apply a rotational force to the excavator, such as a rotary drive device that applies a rotational force to the excavator.

The terms and expressions used in the specification and claims are for the purpose of description only and are not limiting in nature. There is no intention to exclude some equivalent terms or expressions. Moreover, it goes without saying that various modifications are possible within the scope of the technical idea of the present invention. Also, the terms first, second, etc. do not imply a degree or importance, but are used to distinguish one element from another.

1 rotary excavator 2, 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h, 2i excavator 2R rotary shaft of device main body 21, 21i air tank 210 tank body 211 air introduction part 212, 212i fourth connection Portion 213 Spiral blade 214 Opening 215 Flow passage 216 Female thread 217 Welding portion 218 Fitting hole 219 Connection bolt 21M Maximum diameter portion of tank body 22, 22i Device main body 220, 220a, 220b, 220c, 220d, 220e, 220f, 220g , 220h, 220i Drive unit 221, 221i Body 222, 222i Third connection part 223 First connection part 224 Drive unit storage part 225 Male screw 226 Air introduction hole 22M Maximum diameter part of device body 25 Chuck guide 250 Guide hole 251 Connection Bolt 252 Second connecting portion 253 Recessed portion 254 Rubber ring 26, 26a, 26b1, 26b2, 26c1, 26c2, 26f1, 26f2, 26g, 26h Excavation bit 260 Connection shaft portion 261 Head portion 262, 262a, 262b1, 262b2, 262c1, 262c2 , 262f1, 262f2, 262g, 262h Impact surface 263 Air inlet 264 Air outlet 265 Air flow path 266 Exhaust guide groove 267, 267a, 267b1, 267b2, 267c1, 267c2 Corner 268 Ridge impact part 27 Air distribution part 270 Air Receiving portion 271 Support base portion 3 Rotation drive device 30 Body portion 31 Rotary table 311 Insertion hole 32 Support leg 34 Hanging shaft 341 Air supply pipe 4 Anti-rotation structure 41 First insertion hole 42 Second insertion hole 43 Anti-rotation shaft 9 Drilling device 91 Central bit 92 Peripheral bit 93 Prototype 930 Drilling bit 931 Striking surface 933 Corner 934 Tip 9R Rotating shaft H Object to be drilled H1 Drilling hole H6 Central convex part H7 Central deformation part

Claims (8)

A plurality of drive unit storage portions are provided rotatably about a rotation axis and parallel to the rotation shaft, and a portion other than the drive unit storage portion has a substantially solid structure, and the first connection a device main body having a body portion formed on one end side, and a drive unit using air as a power source and arranged for each of the drive unit storage portions;
a chuck guide having a second connection portion connected to the first connection portion with a fitting structure and having a plurality of guide holes, which are through holes linearly communicating with the drive unit storage portion;
It has a connection shaft portion that is individually inserted into the guide hole and moves back and forth in the axial direction upon receiving a driving force from the drive unit, and a head portion that includes a striking surface provided at the tip of the connection shaft portion. , a plurality of drilling bits, and
an air tank having a tank body connected to the other end side of the body and capable of feeding air to each of the drive units, and an air introduction part capable of introducing air into the tank body;
an air distribution unit capable of distributing the air supplied from the air tank to the drive unit so that part or all of the drilling bits advance and retreat at different timings ,
A third connecting portion formed on the other end side of the barrel portion of the apparatus main body, and the third connecting portion formed on the tank barrel portion of the air tank, at a connecting portion between the apparatus main body and the air tank. and a fourth connection portion connected with a fitting structure, and a detachment suppression structure for suppressing detachment of the third connection portion and the fourth connection portion in the fitted state,
The third connecting portion is a convex portion having a diameter smaller than the outer diameter of the intermediate portion in the longitudinal direction of the trunk portion, and has a structure in which a male screw is threaded on the side surface of the convex portion. , the opening end of the tank body having an inner diameter that allows the third connection portion to be tightly fitted, and a female screw that is screwed with the male screw is threaded on the inner surface near the opening end.
drilling rig. The excavator according to claim 1 , wherein a welded portion is formed on an outer surface of a connecting portion between the air tank and the device main body . The first connecting portion is a convex portion having a diameter smaller than the outer diameter of the intermediate portion in the longitudinal direction of the trunk portion, and in an end view, the convex portion has a concave curved surface that does not overlap with the opening portion of the drive unit storage portion. is a structure in which a notch is formed in
The second connecting portion has a structure in which a concave portion capable of tightly fitting the first connecting portion is formed in the end face of the connecting portion with the main body of the device.
Drilling equipment according to claim 2. A detent structure is provided at a contact portion between the first connection portion and the second connection portion.
A drilling rig according to claim 3 . In an end view of the excavator in the excavation direction, the striking surfaces of the respective drilling bits are arranged around the rotation axis of the chuck guide, and only one of the striking surfaces is arranged so as to overlap with the rotation axis. A first arrangement mode, or a corner portion is formed on the rotating shaft side of the striking surface, and only the edge portions on the rotating shaft side of a pair of the striking surfaces arranged opposite to each other across the rotating shaft rotate in the same manner. A second arrangement mode in which the tip of the corner portion overlaps with the shaft and is arranged so that the tip of the corner portion does not overlap with the rotation shaft, and the edge portion of each of the striking surfaces on the side of the rotation shaft rotates in the same direction. It is a configuration that is gathered so as to be close to the axis
The drilling rig according to any one of claims 1 to 4. Each of the drive units is configured such that one drive unit and the other drive unit can supply different driving forces, and in the first arrangement mode, the drilling bit is arranged such that the striking surface overlaps with the rotating shaft. or, in the second arrangement mode, the drilling bit in which the striking surface overlaps the rotary shaft only at the side edge of the rotary shaft. It is a structure that allocates a drive unit that supplies driving force
A drilling rig according to claim 5 . Each of the excavation bits has a ridge striking portion projecting from the striking surface toward the object to be excavated along a position corresponding to the outer peripheral edge of the excavation bit when viewed in the direction of the rotation axis of the chuck guide.
The drilling rig according to any one of claims 1 to 6. A plurality of drive unit storage portions are provided rotatably about a rotation axis and parallel to the rotation shaft, and a portion other than the drive unit storage portion has a substantially solid structure, and the first connection a body portion formed on one end side, an apparatus main body including a drive unit that uses air as a power source and is arranged for each of the drive unit storage portions, and a first connection portion that is connected to the first connection portion with a fitting structure. 2 connection portions are formed, and a plurality of guide holes, which are through holes linearly communicating with the drive unit storage portion, are formed in a chuck guide; A plurality of excavation bits, each of which includes a connection shaft portion that moves forward and backward in the axial direction under force, and a head portion that includes a striking surface provided at the tip of the connection shaft portion, is connected to the other end side of the body portion. an air tank including a tank body capable of feeding air to each of the drive units; an air introduction portion capable of introducing air supplied from the outside into the tank body; an air distribution part capable of distributing the air supplied to the unit so that part or all of the drilling bits advance and retreat at different timings;
A third connecting portion formed on the other end side of the barrel portion of the apparatus main body, and the third connecting portion formed on the tank barrel portion of the air tank, at a connecting portion between the apparatus main body and the air tank. and a fourth connection portion connected with a fitting structure, and a detachment suppression structure for suppressing detachment of the third connection portion and the fourth connection portion in the fitted state,
The third connecting portion is a convex portion having a diameter smaller than the outer diameter of the intermediate portion in the longitudinal direction of the trunk portion, and has a structure in which a male screw is threaded on the side surface of the convex portion. , the opening end of the tank body having an inner diameter that allows the third connection portion to be tightly fitted, and a female screw that is screwed with the male screw is threaded on the inner surface near the opening end.
a drilling rig;
a rotary drive device that imparts a rotary force to the excavator;
have
rotary excavator.

Images