US-12617027-B2 - Two-hole core drilling machine

US12617027B2US 12617027 B2US12617027 B2US 12617027B2US-12617027-B2

Abstract

A two-hole core drilling machine of the invention includes a body, a vertically reciprocating carriage vertically reciprocably mounted to the body, a fixing plate coupled to one side surface of the carriage, to rotatably support a drive shaft of a motor, a pivoting plate fastened to the fixing plate under a condition that a pivot angle of the pivoting plate is changed, a moving plate fastened to the pivoting plate under a condition that a length of the moving plate from the pivoting plate is varied, a belt or chain mounted between a drive pulley coupled to the drive shaft and a driven pulley coupled to a driven shaft rotatably mounted to the moving plate, a first core bit coupled to the drive shaft, and a second core bit coupled to the driven shaft.

Inventors

Sung Jun Lee
Chae Mun LEE

Assignees

EGUN CO., LTD.

Dates

Publication Date: 20260505
Application Date: 20220722
Priority Date: 20210802

Claims (9)

1 . A two-hole core drilling machine comprising: a body; a vertically reciprocating carriage vertically reciprocally mounted to the body; a fixing plate coupled to one side of the carriage, to rotatably support a drive shaft of a motor; a pivoting plate fastened to the fixing plate under a condition that a pivot angle of the pivoting plate is changed; a moving plate fastened to the pivoting plate under a condition that a distance of the moving plate from the fixing plate is varied, a driven shaft being rotatably mounted to the moving plate; a gear train coupled between the drive shaft and the driven shaft, to transmit rotation force of the drive shaft to the driven shaft; a first core bit coupled to the drive shaft; and a second core bit coupled to the driven shaft.
2 . The two-hole core drilling machine according to claim 1 , wherein: the fixing plate comprises a plurality of fastening holes arranged on a circumference having a predetermined radius from the drive shaft; the pivoting plate comprises a plurality of fastening holes extending vertically through the pivoting plate; and the pivoting plate is fixed at a predetermined pivot position with respect to the fixing plate by fasteners fastened through the plurality of fastening holes of the fixing plate and the plurality of fastening holes of the pivoting plate.
3 . The two-hole core drilling machine according to claim 2 , wherein: the pivoting plate comprises a plurality of slots formed along a length in a longitudinal direction; the moving plate comprises a plurality of fastening holes formed to extend vertically through the moving plate; and the moving plate is fixed at a predetermined position in a longitudinal direction with respect to the pivoting plate by fasteners fastened to the plurality of fastening holes and the plurality of slits.
4 . The two-hole core drilling machine according to claim 3 , wherein water supply hoses are connected to a middle portion of the drive shaft and an upper portion of the driven shaft, respectively, to supply cooling water.
5 . The two-hole core drilling machine according to claim 1 , wherein the gear train comprises: a first link bracket pivotably mounted to the drive shaft; a second link bracket pivotably connected, at one end thereof, to the first link bracket while being pivotably mounted, at another end thereof, to the driven shaft; a drive gear coupled to the drive shaft, to be rotatable by the drive shaft; a first intermediate gear mounted to the first link bracket while engaging with the drive gear; a second intermediate gear mounted to connection portions of the first link bracket and the second link bracket while engaging with the first intermediate gear; a third intermediate gear mounted to the first link bracket while engaging with the second intermediate gear; and a driven gear coupled to the driven shaft while engaging with the third intermediate gear, to be rotatable by the third intermediate gear.
6 . The two-hole core drilling machine according to claim 1 , wherein: the body comprises: a base fixed to a structure to be drilled; and a stand vertically coupled to the base and formed with a gear at one side surface thereof.
7 . The two-hole core drilling machine according to claim 1 , wherein the carriage is provided with a pinion engaged with a gear, and is vertically reciprocally mounted to a stand.
8 . The two-hole core drilling machine according to claim 1 , wherein the carriage is vertically reciprocally mounted to a stand by a hydraulic cylinder.
9 . The two-hole core drilling machine according to claim 1 , wherein a guide groove configured to guide movement of the moving plate is formed at an upper surface of the pivoting plate.

Description

TECHNICAL FIELD The present invention relates to a core drilling machine, and more particularly to a two-hole core drilling machine. BACKGROUND ART A core drilling machine is a mechanical apparatus for drilling a hole into a wall, a ceiling, etc. upon piping construction in a building. Generally, such a core drilling machine constitutes a core drill assembly together with various devices configured to manipulate a core drill. A general core drill assembly, which is currently used, includes a base fixed to a structure, into which a hole is to be drilled, by an anchor bolt, a stand disposed to be perpendicular to the base and formed with a rack at one side surface thereof, a driving body with a pinion mounted therein, the driving body being vertically reciprocable along the stand in accordance with a rotating operation of a handle, and a core drill mounted to the driving body and configured to drill a hole into a particular portion of the structure. Here, the core drill is constituted by a core bit configured to drill a hole into the structure through frictional contact between the core bit and the structure, and a drive motor configured to rotate the core bit at a high speed. The core drill assembly having the above-mentioned configuration operates as follows. When the handle installed at the driving body is rotated in a state in which the base is fixed to a wall or a bottom surface of the structure using a plurality of anchor bolts, the pinion of the driving body, which engages with the rack of the stand, moves along the rack. As a result, the driving body reciprocates vertically along the stand. In this state, when electric power is applied to the drive motor, the core bit is rotated. The core bit, which rotates at a high speed, drills a hole into the structure while moving forwards. However, such a conventional core drilling machine performs drilling using only one core bit mounted thereto. For this reason, for drilling of a plurality of holes, the core drilling machine should be moved to hole positions one by one, and tasks for fixing the core drilling machine using anchor bolts and drilling a hole should be performed for the hole positions one by one. As a result, there are problems in that work is troublesome, and a lot of time is taken. In particular, in a working environment in a large-scale factory requiring rapid drilling of a number of holes, use of only the conventional core drilling machine may cause a problem in that high costs are taken because a number of workers should be committed, in addition to a problem of an increased working time. The present invention proposes a two-hole core drilling machine in order to solve the above-mentioned problems. DISCLOSURE Technical Problem It is an object of the present invention to provide a two-hole core drilling machine. Technical Solution In accordance with an aspect of the present invention, the above and other objects can be accomplished by the provision of a two-hole core drilling machine including a body, a vertically reciprocating carriage vertically reciprocably mounted to the body, a fixing plate coupled to one side surface of the carriage, to rotatably support a drive shaft of a motor, a pivoting plate fastened to the fixing plate under a condition that a pivot angle of the pivoting plate is changed, a moving plate fastened to the pivoting plate under a condition that a length of the moving plate from the pivoting plate is varied, a belt or chain mounted between a drive pulley coupled to the drive shaft and a driven pulley coupled to a driven shaft rotatably mounted to the moving plate, a first core bit coupled to the drive shaft, and a second core bit coupled to the driven shaft. The body may include a base fixed to a structure to be drilled, and a stand vertically coupled to the base and formed with a gear at one side surface thereof. The carriage may be provided with a pinion engaged with the gear, and may be vertically reciprocably mounted to the stand. The fixing plate may include a pivot guide slit formed through the fixing plate while having an arc shape. The pivoting plate may include a plurality of fastening holes formed to extend vertically through the pivoting plate. The pivoting plate may be fixed at a predetermined pivot position with respect to the fixing plate by fasteners fastened to the plurality of fastening holes and the pivot guide slit. The pivoting plate may include a movement guide slit formed lengthily in a longitudinal direction. The moving plate may include a plurality of fastening holes formed to extend vertically through the moving plate. The moving plate may be fixed at a predetermined position in a longitudinal direction with respect to the pivoting plate by fasteners fastened to the plurality of fastening holes and the movement guide slit. The moving plate may further include a tension roller configured to be fixed after a rotation shaft of the tension roller moves toward the belt or chain loosened in accordance w