JP2015127135A - SDS plus type shank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shank which belongs to a drilling tool such as a concrete drill or a core drill mounted mainly to an electric power tool and used to drill concrete and is mountable to both an electric power tool having an SDS plus type chuck matching with an SDS plus type shank and an electric power tool having a three-pawl type chuck matching with a straight type shank.SOLUTION: A shank which solves the above-mentioned problem is characterized by being based on an SDS plus type shank and by having a pin detachably attached to at least one of a pair of key grooves processed in the shank and a flat surface at a position off the key grooves, where the pin is mounted, by 120 degrees to right and left. The pin is removed for use to an electric power tool having a chuck matching with an SDS plus type shank, and the pin is mounted for use to an electric power tool having a chuck matching with a straight type shank.

Description

  The present invention relates to an SDS plus type shank used for mounting and fixing a drilling tool such as a concrete drill or a core drill for drilling mainly in concrete or stone to a chuck portion of an electric power tool.

  When drilling holes for attaching anchor bolts or pipes to concrete or stone, when drilling holes, such as concrete drills, core drills, etc., with a cutting edge suitable for the diameter and depth of the holes to be drilled and the material of the material to be drilled In many cases, the shank of this drilling tool is inserted into and mounted on a chuck of an electric tool with a built-in motor, and this is rotated for drilling. The rotational torque necessary for drilling is transmitted from the motor built in the power tool to the shank of the drill tool via the chuck of the power tool, and is transmitted to the cutting edge.

  At the time of drilling, an appropriate method is selected from different drilling methods such as continuous rotation drilling, hammer ring drilling, and impact drilling depending on the material of the material to be drilled. As power tools to be used, SDS plus type chucks developed by overseas tool companies or so-called three-jaw type chucks that are often used in general-purpose drilling machines, etc., are generally used. is there.

  The gripping method is completely different depending on whether the power tool chuck is an SDS plus type or a three-claw type. Therefore, unless a drilling tool with a shank shape corresponding to each chucking method is applied, the chuck and shank will be connected well. It cannot be drilled normally.

  7 and 8 show a drill having an SDS plus shank. FIG. 7 shows a concrete drill 10 including a cutting edge portion 11 and an SDS plus type shank 1. FIG. 8 shows a core drill 11 having an SDS plus type shank 1 and a cutting edge portion 11 capable of drilling a large diameter. In these SDS plus type shanks 1, as shown in FIG. 9, a pair of circular grooves 3 and a pair of key grooves 4 are machined in a circumferential portion 6 on the shank end surface 5 side at a position orthogonal to the circular grooves 3. The cross section is as shown in FIG.

  A pair of key members and a pair of radially movable steel balls are incorporated in the chuck portion of the electric tool to which the SDS plus type shank 1 is mounted, and the key members slide in the key grooves 4 of the shank. The steel ball plays a role of transmitting the rotational torque of the motor built in the electric tool to the drill, and the steel ball fits into the circular groove 3 and functions to grip the drill while being movable in the axial direction.

  When the drill is pushed or pulled in the axial direction by hand while being held by the chuck, the drilling tool is against the electric tool within the range where the steel balls stuck in the circular groove 3 come into contact with both ends in the longitudinal direction of the circular groove. Since the key member in the chuck is in sliding contact with the key groove 4 of the shank 1, the rotational torque of the motor in the power tool is transmitted to the drilling tool. The

  Therefore, when an SDS plus type chuck and a drilling tool are used for drilling work called hammer ring drilling while applying a hammering rotational force to the drilling tool, a part of the reaction from the drilling tool caused by the hammering is caused by the drilling tool and the electric tool. The shock vibration that is absorbed by the relative position fluctuation in the axial direction and is transmitted to the operator drilling with the electric power tool is alleviated, and the work load is reduced.

  On the other hand, as a drilling tool shank used by being mounted on an electric tool having a three-jaw chuck, as shown in FIG. 11, the cylindrical portion 6 is a completely circular rod-shaped shank 13, As shown in FIG. 12, a so-called three-sided round bar-type shank 14 in which three planes 2 are formed at positions that divide the circumferential portion 6 into three equal parts is common. FIG. 13 shows a cross-sectional view of a three-sided round bar shank 14.

  When gripping a drilling tool having a three-sided round bar shank 14 with a three-nail chuck of an electric tool, it is necessary to adjust the angle so that the plane 2 faces the direction of the nail of the chuck. Compared to the mounting of the full round bar shank 13, it is a little troublesome, but the full round bar shank 13 tends to slip between the shank and the claw of the chuck, whereas the three side round bar shank 14 causes this slip. Therefore, it is preferable to use a drilling tool having a three-sided round bar shank 14 for drilling that requires a large rotational torque.

  However, drilling tools such as drills with shanks of full round bars or round bars with three flat surfaces can be used for drilling by attaching them to electric tools of three-jaw type chucks, but key grooves Neither is it applicable to the power tool of the SDS plus type chuck. Conversely, the drilling tool having the SDS plus type shank 1 can be used by being attached to the electric tool of the SDS plus type chuck, but even if it is attached to the electric tool of the three jaw type chuck, the drilling tool of the SDS plus type shank can be used. Due to the characteristic circular groove and key groove, the three claws cannot normally grip the shank and stable drilling is impossible.In the worst case, the claws of the three-jaw chuck are damaged, Accidents occur when the drill is damaged by vibration.

  As mentioned above, drill tools such as SDS plus type shank concrete drills and core drills can be used with power tools of SDS plus type chucks. The drilling torque is not transmitted to the drilling tool, so stable drilling is not possible, and the jaws of the three-jaw chuck slide into the circular or key groove of the SDS plus shank, causing the nails to break or break the drill. Cause problems. Accordingly, there is a problem that the drill tool of the SDS plus type shank can only be used for the power tool of the SDS plus type chuck and cannot be used with the electric tool of the three-jaw type chuck.

  In order to solve the above problems, the present invention provides a pin that can be attached to and detached from at least one of a pair of key grooves machined into a shank, and a position that is shifted 120 degrees to the left and right from the key groove on which the pin is mounted. It is an SDS plus type shank with a flat surface.

  When the chuck method of the electric power tool is the SDS plus type, it is used as an SDS plus type shank without attaching a pin. When the chuck method of the electric tool is a three-claw type, the pin is attached to the keyway, and the claw of the three-claw type chuck is placed on a total of three planes: the pin and two planes machined on the shank circumferential surface. Install and use so that it contacts.

  In the SDS plus type shank according to the present invention, the drilling tool of the SDS plus type shank can be applied to both the electric tool of the SDS plus type chuck and the electric tool of the three-jaw type chuck by simply attaching and detaching the pins. Therefore, the application range as a drilling tool is wide, and there is no need to worry about the combination of the shank type and the chuck of the electric tool during drilling work. Furthermore, the company that manufactures the drilling tool does not need to make two types of drilling tools, that is, an SDS plus type shank drilling tool and a three-sided round bar type shank drilling tool. As long as a drilling tool with a diameter is made, it will be possible to supply drilling tools to the two markets of power tools for SDS plus chucks and three-jaw chucks. There is no stock.

A sketch showing one embodiment of the SDS plus type shank of the present invention The sketch which shows one Example of the pin which can be attached or detached to the SDS plus type | mold shank of this invention The sketch which shows another Example of the pin which can be attached or detached to the SDS plus type shank of this invention FIG. 2 is a sketch showing a state in which the pin shown in FIG. 2 is attached to the SDS plus type shank shown in FIG. Cross-sectional view of the SDS plus shank shown in FIG. FIG. 4 is a cross-sectional view of the shank portion of the SDS plus type shank with a pin attached thereto. Diagram showing one example of a concrete drill with SDS plus shank The figure which shows one example of the core drill which has the SDS plus type shank A sketch of a conventional SDS plus shank Cross-sectional view of the SDS plus shank of FIG. A sketch of a fully round bar shank A sketch of a three-sided round bar shank with three planes Sectional view of the shank of FIG.

  The SDS plus type shank used in combination with the detachable pin according to the present invention has a plane machined at a position shifted 120 degrees left and right from one groove of a pair of key grooves, It is the same as the conventional SDS plus type shank, and therefore the manufacturing method is almost the same as the conventional one.

  Since a flat surface is machined into the shank, a part of the circular groove is scraped off, but the amount of scraping is small, so that the steel ball built in the SDS plus type chuck has a groove depth that can stably grip the shank. The remaining gripping characteristics do not pose any problems even if they are mounted on the SDS plus type chuck. Moreover, since the keyway maintains the same shape as before, the rotation transmission performance is not deteriorated.

  If this shank is used in combination with a pin that can be attached to and detached from the keyway and has a trapezoidal shape that is substantially the same as the cross section of the keyway, a total of three planes will be composed of the pin and two planes that have been pre-processed on the shank. When mounted on the three-jaw chuck, the flat tool and the pawl come into contact with each other and the drilling tool is firmly held, so that the rotational torque of the electric tool is reliably transmitted to the drilling tool. Once gripped with a three-claw chuck, the pin does not fall off due to drilling vibration, etc., so a pin with a simple structure is also practical, so the manufacturing cost of the pin compared to the manufacturing cost of the drilling tool It is minute.

An embodiment of an SDS plus type shank according to the present invention and a pin that can be attached to and detached from the shank will be described with reference to FIGS.
As shown in FIG. 1, the SDS plus type shank 1 of the present invention is characterized by having a plane 2 on the circumferential portion 6 of the conventional SDS plus type shank. Although the cross section is shown in FIG. 5, the plane 2 is provided at a total of two positions at positions shifted by 120 degrees to the left and right from one of the key grooves 4, and the processing depth is a circular groove. 3 is limited to a range in which no significant change occurs in the shape of 3.

  A U-shaped pin 7 which can be attached to and detached from the SDS plus type shank 1 is shown in FIG. The shape is similar to the letter “K” in Katakana, and it has two trapezoidal claws 8 that fit firmly into the pair of key grooves 4 of the SDS plus type shank 1.

  FIG. 4 shows a state where the U-shaped pin 7 is fitted in the SDS plus type shank 1 of FIG. 1 of the present invention, and FIG. As can be seen in FIG. 6, a trapezoidal claw 8 is fitted into the pair of key grooves 4, and two planes 2 are arranged at positions shifted from the trapezoidal claw 4 on one side by 120 degrees to the left and right.

  In the SDS plus type shank 1 shown in FIG. 1 of the present invention without a detachable pin, the two circular grooves 3 are still sufficient although the two planes 2 are processed in the circumferential portion 6. In addition, since the two key grooves 4 do not overlap with the plane 2 while maintaining a circular shape, even if it is mounted on an electric tool of an SDS plus type chuck and used, the conventional SDS plus type shank without the plane 2 Equivalent gripping characteristics and rotational torque transmission characteristics are maintained, and no problems occur in drilling operations.

  When it is necessary to drill with a three-jaw chuck electric tool, the U-shaped pin 7 of FIG. 2 is inserted into the two key grooves 4, and the pin 7 and the SDS plus type shank 1 are integrated as shown in FIG. If the nail of the three-jaw chuck is inserted and gripped so that the two claws of the three-jaw chuck and the two planes 2 of the shank 1 and the trapezoidal nails 8 are aligned, drilling is possible even with the electric tool of the three-jaw chuck. is there.

  As a detachable pin, as shown in FIG. 3, a so-called trapezoidal pin 9 having the same cross section as that of the key groove 4 of the SDS plus type shank 1 may be used. Since it may drop when attached to the chuck, if the trapezoidal pin 9 is magnetized or a small magnet is fixed to a part of the trapezoidal pin 9, the shank and the pin are integrated by magnetic force, so the drill can be attached and detached Sometimes it becomes difficult for the pins to fall off, improving workability.

  In addition, with the U-shaped pin of FIG. 2, one or both tip portions of the two trapezoidal claws 8 are bent inward, and the shank is processed with a small depression at a position corresponding to this bending. When the U-shaped pin is inserted into the keyway, the bent part of the pin fits into the recess of the shank, so the combination of the U-shaped pin and the shank is stable, and the work for attaching and detaching to the electric tool of the three-claw chuck In addition to being easy, problems such as losing pins when stored in a tool box or the like are less likely to occur.

DESCRIPTION OF SYMBOLS 1 SDS plus type shank 2 Plane 3 Circular groove 4 Key groove 5 Shank end surface 6 Circumferential part 7 U-shaped pin 8 Trapezoidal claw 9 Trapezoidal pin 10 Concrete drill 11 Cutting edge 12 Core drill 13 Full round bar type shank 14 Three side round bar type shank

Claims (1)

An SDS-plus-type shank having a pin that can be attached to and detached from at least one of a pair of key grooves processed into a shank, and a plane that is shifted 120 degrees to the left and right from the key groove on which the pin is mounted.

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