WO2013154271A1

WO2013154271A1 - Rotary head of large-diameter drilling machine

Info

Publication number: WO2013154271A1
Application number: PCT/KR2013/002082
Authority: WO
Inventors: Sun Keun Park
Original assignee: Core Geotechnics Co., Ltd.
Priority date: 2012-04-13
Filing date: 2013-03-15
Publication date: 2013-10-17
Also published as: KR101334298B1; KR20130115841A

Abstract

Disclosed therein is a rotary head of a large-diameter drilling machine, which rotates a rod connected with a head of the drilling machine. The rotary head includes: a gear box being composed of upper and lower flanges and a side plate and having an inner space of a closed structure; an interlocking gear formed in a shape of an annular ring having teeth formed on inner and outer peripheries thereof, the interlocking gear being mounted in the middle of the inner space of the gear box; a plurality of driving gears being smaller than the interlocking gear and being gear-coupled to the outer periphery of the interlocking gear inside the gear box, the driving gears being driven by receiving a driving power of a motor; a center shaft protruding upwardly and downwardly from the upper and lower flanges of the gear box while passing through the inside of the annular ring of the interlocking gear and penetrating the upper and lower flanges of the gear box, the center shaft being gear-coupled with the inner periphery of the interlocking gear and connected with the rod so as to rotate the rod while rotating according to the rotation of the interlocking gear; couplers respectively covering the portions of the center shaft, which respectively protrude upwardly and downwardly from the upper and lower flanges of the gear box, the couplers being fixed to the upper and lower flanges of the gear box through bolt-tightening; and plain bearings made of engineering plastic and contactingly mounted between the center shaft and the couplers.

Description

ROTARY HEAD OF LARGE-DIAMETER DRILLING MACHINE

The present invention relates to a rotary head for rotating and propelling a rod connected with a cutting device of a large-diameter drilling machine, and more particularly, to a rotary head of a large-diameter drilling machine, which has a simple assembling structure and is favorable to perforate a large-diameter hole because it propels while effectively rotating the rod.

In the foundation work for reinforcing the ground or for supporting structures, drilling into the ground must be preceded, and the drilling into the ground is carried out using a drilling machine. FIG. 1 illustrates an example of a drilling machine having a hammer as a cutting device. As shown in FIG. 1, the drilling machine includes the hammer which is the cutting device and a rod connected with the cutting device and rotated and propelled by a rotary head. While the rod is rotated and propelled by a rotary driving force of the rotary head, the cutting device cut the ground while being rotated and pressed.

In the meantime, in order to construct large-diameter mono piles, such as mono piles of the foundation of a off shore wind turbine, large-diameter holes are perforated before the mono pile construction. In order to perforate the large-diameter holes, a drilling machine with a great torque of the rod is needed. Conventionally, in order to increase the torque of the rod, a method of supplying a high power using a rotary head by a large-sized motor is mostly adopted. The large-sized motor makes the size of the drilling machine larger, and hence, it is a factor to decrease workability and economic feasibility. Moreover, there is a limit in application of the large-sized motor because it is produced no more than a predetermined size. In order to solve the above problems, a rotary head using a plurality of small-sized motors has been proposed.

Such a rotary head adopts a method of rotating the rod through a large-sized interlocking gear driving in interlock with a plurality of driving gears driven by the small-sized motors. Korean Patent Laid-open No. 10-2011-0119187 discloses such a rotary head. However, such a rotary head is nothing but propose a way to increase the torque of the interlocking gear through a gear reduction. That is, the rotary head cannot suggest a concrete method to effectively transmit the increased torque to the rod to rotate the rod. Furthermore, the conventional rotary head causes an increase of manufacturing costs of the drilling machine due to a complicated assembling structure.

Accordingly, the present invention has been made in an effort to solve the above-mentioned problems occurring in the prior arts, and it is an object of the present invention to provide a rotary head of a large-diameter drilling machine, which has a simple assembling structure and is favorable to perforate a large-diameter hole because it propels while effectively rotating the rod.

It is another object of the present invention to provide a rotary head of a large-diameter drilling machine, which can prevent a frequent replacement due to brokenness of a bearing when a large-diameter hole is perforated.

To achieve the above objects, the present invention provides a rotary head of a large-diameter drilling machine, which rotates a rod connected with a head of the drilling machine, including: a gear box being composed of upper and lower flanges and a side plate and having an inner space of a closed structure; an interlocking gear formed in a shape of an annular ring having teeth formed on inner and outer peripheries thereof, the interlocking gear being mounted in the middle of the inner space of the gear box; a plurality of driving gears being smaller than the interlocking gear and being gear-coupled to the outer periphery of the interlocking gear inside the gear box, the driving gears being driven by receiving a driving power of a motor; a center shaft protruding upwardly and downwardly from the upper and lower flanges of the gear box while passing through the inside of the annular ring of the interlocking gear and penetrating the upper and lower flanges of the gear box, the center shaft being gear-coupled with the inner periphery of the interlocking gear and connected with the rod so as to rotate the rod while rotating according to the rotation of the interlocking gear; couplers respectively covering the portions of the center shaft, which respectively protrude upwardly and downwardly from the upper and lower flanges of the gear box, the couplers being fixed to the upper and lower flanges of the gear box through bolt-tightening; and plain bearings made of engineering plastic and contactingly mounted between the center shaft and the couplers.

The rotary head of the large-diameter drilling machine according to the present invention can rotate the rod effectively, is favorable to perforate a large-diameter hole, and has a simple assembling structure. Particularly, the rotary head according to the present invention has simple components, and is economical due to a long exchange cycle because the components are usable even though the surfaces of the components are worn out and transformed.

FIG. 1 is a brief diagram of a drilling machine.

FIG. 2 is a perspective view of a rotary head of a large-diameter drilling machine according to the present invention.

FIG. 3 is a sectional view showing an assembled state of the rotary head of FIG. 2.

FIG. 4 is an exploded perspective view of the rotary head of FIG. 2.

(Explanation of essential reference numerals in drawings)

100: rotary head

110: gear box

111: upper flange

112: lower flange

113: side plate

120: interlocking gear

130: driving gear

140: center shaft

141: protrusion band

151: upper coupler

152: lower coupler

161: upper bearing

162: lower bearing

151a, 161a: first fragment

151b, 161b: second fragment

T: tapered portion

M: motor

D: decelerator

C: cable

Reference will be now made in detail to the preferred embodiment of the present invention with reference to the attached drawings.

FIG. 2 is a perspective view of a rotary head 100 of a large-diameter drilling machine according to the present invention, FIG. 3 is a sectional view showing an assembled state of the rotary head 100 of FIG. 2, and FIG. 4 is an exploded perspective view of the rotary head 100 of FIG. 2.

As shown in the drawings, the present invention relates to the rotary head 100 for rotating a rod connected with a cutting device, and is characterized by a simple assembly structure of gears and a bearing installation structure for effective rotation of a rod.

In detail, the rotary head 100 of the large-diameter drilling machine according to the present invention includes: a gear box 110 being composed of upper and

lower flanges

111 and 112 and a side plate 113, and having an inner space of a closed structure; an interlocking gear 120 formed in a shape of an annular ring having teeth formed on inner and outer peripheries, the interlocking gear 120 being mounted in the middle of the inner space of the gear box 110; a plurality of driving gears 130 being smaller than the interlocking gear 120 and being gear-coupled to the outer periphery of the interlocking gear 120 inside the gear box 110, the driving gears 130 being driven by receiving a driving power of a motor; a center shaft 140 protruding upwardly and downwardly from the upper and

lower flanges

111 and 112 of the gear box 110 while passing through the inside of the annular ring of the interlocking gear 120 and penetrating the upper and

lower flanges

111 and 112 of the gear box 110, the center shaft 140 being gear-coupled with the inner periphery of the interlocking gear 120 and connected with the rod so as to rotate the rod while rotating according to the rotation of the interlocking gear 120;

couplers

151 and 152 respectively covering the portions of the center shaft 140, which respectively protrude upwardly and downwardly from the upper and

lower flanges

111 and 112 of the gear box, the

couplers

151 and 152 being fixed to the upper and

lower flanges

111 and 112 of the gear box through bolt-tightening; and

plain bearings

161 and 162 made of engineering plastic and contactingly mounted between the center shaft 140 and the

couplers

151 and 152. Here, because the center shaft 140 protrudes upwardly and downwardly from the upper and

lower flanges

111 and 112 of the gear box, the

couplers

151 and 152 and the

bearings

161 and 162 are divided into an upper coupler 151 and an upper bearing 161 respectively mounted on the upper flange 111 of the gear box and a lower coupler 152 and a lower bearing 162 respectively mounted beneath the lower flange 112 of the gear box.

The rotary head 100 according to the present invention can be assembled just by fixing and mounting the

couplers

151 and 152 and the center shaft 140 to the upper and

lower flanges

111 and 112 of the gear box through the bolt-tightening so as to simply restrict the interlocking gear 120 and the driving gear 130 to the gear box 110. Moreover, because the

bearings

161 and 162 are contactingly mounted between the

couplers

151 and 152 and the center shaft 140, the torque of the center shaft 140 is transmitted to the rod without any loss to thereby enhance the torque of the rod. Particularly, because the

bearings

161 and 162 are made of engineering plastic, the rotary head 100 according to the present invention is economical and has a simple structure.

FIG. 2 illustrates an example that four driving gears 130 are arranged around the interlocking gear 120 in the rectangular composition. Of course, because there are four driving gears 130 around the interlocking gear 120, four motors (M) and four decelerators (D) for respectively driving the four driving gears 130 are prepared. Additionally, cables for lifting the rotary head 100 may be disposed. Here, it is preferable that the motors (M) are track motors. Because the motors (M), the decelerators (D) and the lifting cables (C) are mounted in the same way as the conventional drilling machine, detailed descriptions of them will be omitted.

FIG. 3 is a sectional view showing an assembled state of the rotary head 100 of FIG. 2, and FIG. 4 is an exploded perspective view of the rotary head 100, and in FIGS. 3 and 4, an assembling structure for simply and stably mounting the

couplers

151 and 152 and the

bearings

161 and 162 is illustrated.

As shown in the drawings, the interlocking gear 120 is thinner than the height of the inner space of the gear box 110 and is spaced apart from the upper and

lower flanges

111 and 112 of the gear box, and hence, the interlocking gear 120 freely rotates inside the gear box 110. The lower bearing 162 is fit between the interlocking gear 120 and the lower flange 112 of the gear box in order to effectively support the rotation of the interlocking gear 120 without any interference. Such a lower bearing 162 is located to a position between the center shaft 140 and the lower coupler 152.

In addition, in FIGS. 3 and 4, the lower coupler 152 is an annular ring member of a 'ㅏ' shaped cross section having an outward wing. The lower coupler 152 is fit between the lower flange 112 of the gear box and the center shaft 140 and fixed to the lower flange 112 of the gear box by tightening a bolt to the outward wing.

Therefore, the lower flange 112 of the gear box, the lower coupler 152, the lower bearing 162 and the center shaft 140 are closely joined in a contact state just by tightening the bolt to the lower flange 112 of the gear box and the lower coupler 152. In this instance, it is preferable that the inner peripheral surface of the lower coupler 152 and the outer peripheral surface of the lower bearing 152 are tapered and contactingly mounted in order to prevent a damage of the bearing due to a stress concentration at an edge. Here, if the tapered portion (T) of the lower coupler 152 is galvanized, the tapered portion (T) of the lower coupler 152 can more effectively cope with the rotary power of the center shaft 140 together with the lower bearing 162 made of engineering plastic.

In the meantime, the upper coupler 151 and the upper bearing 161 are mounted above the upper flange 111 of the gear box, and in FIGS. 3 and 4, are mounted conjunctly with the center shaft 140 through the groove-protrusion combination. The center shaft 140 has a protrusion band 141 formed at the center of the outer peripheral surface thereof, and the upper coupler 151 and the upper bearing 161 respectively have grooves for receiving the protrusion band 141 of the center shaft to form the groove-protrusion combination.

Particularly, the upper coupler 151 has a first fragment 151a and a second fragment 151b for tightening bolts, and it is the result of consideration that it is difficult to batch-install the upper coupler 151 by the protrusion band 141 of the center shaft during the process of assembling and manufacturing the rotary head 100. That is, the first fragment 151a is an annular ring member of a 'ㅏ' shaped cross section having an inward wing and is fit under the protrusion band 141 of the center shaft 140 in such a way as to face the side of the protrusion band 141, and the second fragment 151b is an annular ring member of an 'L' shaped cross section having an outward wing and is mounted in such a way as to face the upper portion of the center shaft 140, which is located above the protrusion band 141, above the first fragment 151a. After that, the second fragment 151b is joined to the first fragment 151a by tightening a bolt.

Of course, the upper bearing 161 is mounted between the center shaft 140 and the first and

second fragments

151a and 151b of the upper coupler, but in this instance, the upper bearing 161 mounted between the center shaft 140 and the second fragment 151b of the upper coupler is mounted in such a manner that a second fragment 161b being an annular ring member of a 'ㄱ' shaped cross section having an outward wing is separated from a first fragment 161a of a disc ring as shown in FIG. 3 so as to mount the second fragment 151b of the upper coupler between the first fragment 161a and the second fragment 161b.

Through the above, the coupler 151, the lower bearing 162 and the center shaft 140 are closely joined and seated and fixed on the upper flange 111 of the gear box in a state where they are engaged with each other and are in contact with each other just by assembling the second fragment 151b of the upper coupler to the first fragment 151a via a bolt. Particularly, in FIGS. 3 and 4, the second fragment 151b of the upper coupler is assembled only to the first fragment 151a via the bolt and the first fragment 151a of the upper coupler is closely fixed to the upper flange 111 of the gear box through the tightening force of the bolt. However, it is also possible to fasten the bolt to the upper flange 111 of the gear box by penetrating the first fragment 151a of the upper coupler. Moreover, it is also preferable that the upper coupler 151 and the upper bearing 161 are tapered and contactingly mounted and the tapered portion (T) of the upper coupler is galvanized, so that an exchange cycle of components can be extended because the surface roughness is moderated.

As described above, while the present invention has been particularly shown and described with reference to the example embodiments thereof, it will be understood by those of ordinary skill in the art that the above embodiments of the present invention are all exemplified and various changes, modifications and equivalents may be made therein without departing from the scope of the present invention. Therefore, it would be understood that the technical and protective scope of the present invention shall be defined by the technical idea as defined by the following claims.

Claims

A rotary head of a large-diameter drilling machine for rotating a rod connected with a head of the drilling machine, the rotary head comprising:

a gear box (110) being composed of an upper flange (111), a lower flange (112), and a side plate (113) and having an inner space of a closed structure;

an interlocking gear (120) formed in a shape of an annular ring having teeth formed on inner and outer peripheries thereof, the interlocking gear (120) being mounted in the middle of the inner space of the gear box (110);

a plurality of driving gears (130) being smaller than the interlocking gear (120) and being gear-coupled to the outer periphery of the interlocking gear (120) inside the gear box (110), the driving gears (130) being driven by receiving a driving power of a motor;

a center shaft (140) protruding upwardly and downwardly from the upper and lower flanges (111, 112) of the gear box (110) while passing through the inside of the annular ring of the interlocking gear (120) and penetrating the upper and lower flanges (111, 112) of the gear box (110), the center shaft (140) being gear-coupled with the inner periphery of the interlocking gear (120) and connected with the rod so as to rotate the rod while rotating according to the rotation of the interlocking gear (120);

couplers (151, 152) respectively covering the portions of the center shaft (140), which respectively protrude upwardly and downwardly from the upper and lower flanges (111, 112) of the gear box, the couplers (151, 152) being fixed to the upper and lower flanges (111, 112) of the gear box through bolt-tightening; and

plain bearings (161, 162) made of engineering plastic and contactingly mounted between the center shaft (140) and the couplers (151, 152).
The rotary head according to claim 1, wherein the interlocking gear (120) is thinner than the height of the inner space of the gear box (110) and is spaced apart from the lower flange (112) of the gear box,

wherein the lower coupler (152) mounted at a lower portion of the center shaft (140) is fit between the lower flange (112) of the gear box and the center shaft (140) and is fixed to the lower flange (112) of the gear box through bolt-tightening,

wherein the lower bearing (162) mounted at a lower portion of the center shaft (140) is fit between the lower flange (112) of the gear box and the interlocking gear (120), and

wherein the inner periphery of the lower coupler 152 and the outer periphery of the lower bearing (162) are tapered and contactingly mounted.
The rotary head according to claim 1, wherein the interlocking gear (120) is thinner than the height of the inner space of the gear box (110) and is spaced apart from the upper flange (111) of the gear box,

wherein the portion of the center shaft (140), which protrudes upwardly from the upper flange (111) of the gear box has a protrusion band (141) formed at the center of the outer peripheral surface thereof,

wherein the upper coupler (151) mounted at the upper portion of the center shaft (140) comprises: a first fragment (151a) fit under the protrusion band (141) of the center shaft (140) in such a way as to face the side of the protrusion band (141); and a second fragment (151b) mounted above the first fragment (151a) in such a way as to face the center shaft (140), which is located above the protrusion band 141, so that the upper coupler (151) is fixed to the upper flange (111) of the gear box through bolt-tightening of the second fragment (151b),

wherein the upper bearings (161) mounted at the upper portion of the center shaft (140) are respectively mounted above and beneath the protrusion band (141) of the center shaft, and

wherein the inner peripheries of the first fragment (151a) and the second fragment (151b) of the upper coupler and the outer periphery of the upper bearing (161) are tapered and contactingly mounted.
The rotary head according to claim 2 or 3, wherein the couplers (151, 152) are galvanized at the tapered portions (T)
The rotary head according to one of claims 1 to 3, wherein the four driving gears (130) are arranged around the outer periphery of the interlocking gear (120) in the rectangular composition.
The rotary head according to claim 5, wherein the driving gears (130) are driven by track motors.