This HEMS (200) is provided with a control unit (230) that, if an operation directive does not go through a server (600) provided externally to a customer's home (10), identifies said operation directive as having come from within the customer's home, and if the operation directive does go through the server (600) provided externally to the customer's home (10), identifies the operation directive as having come from outside the customer's home.

A drill according to an embodiment of the present invention has a pair of main cutting edges positioned at a front end of a drill body, a pair of first chisel edges each extending from the pair of main cutting edges toward a rotation axis, and a second chisel edge positioned between the pair of first chisel edges and intersecting with the rotation axis of the drill body. When viewing a locus of rotation of the pair of first chisel edges and a locus of rotation of the second chisel edge in a cross section taken so as to include the rotation axis, the respective locus of rotation of the pair of first chisel edges have a rectilinear shape, and respective imaginary straight lines obtained by extending the locus of rotation of the pair of first chisel edges toward the rotation axis are positioned further to a rear end side of the drill body than the locus of rotation of the second chisel edge.

The present invention relates to a step drill bit, characterized in that the step drill bit has a hole processing portion and at least two flutes extending on the hole processing portion, the hole processing portion comprising step sections, each step section and the at least two flutes forming at least two cutting edges distributed in a circumferential direction of the step section, wherein, the at least two cutting edges on at least one of the step sections at least comprise a first cutting edge and a second cutting edge, wherein the first cutting edge and the second cutting edge are respectively constructed in at least two-segment style, and therefore respectively include at least two cutting edge segments, wherein the first cutting edge and the second cutting edge are at least partially different from each other in the structure of their cutting edge segments, or one cutting edge of the first cutting edge and the second cutting edge is formed in one-segment style, while the other cutting edge is formed in at least two-segment style, and thus includes at least two cutting edge segments. The present invention further relates to a method for drilling a workpiece by using a step drill bit.

A drill includes a cutting section having a cylindrical shape and configured to be rotated about a rotation axis. The cutting section includes a first cutting section and a second cutting section, at a front end portion thereof, a first flute continuous with the first cutting section and extending helically around the rotation axis toward a rear end of the cutting section, and a second flute continuous with the second cutting section and extending helically around the rotation axis toward the rear end of the cutting section. The first cutting section includes a first inner cutting edge and a first outer cutting edge positioned closer to the outer peripheral surface than the first inner cutting edge and gradually inclined to the rear end of the cutting section toward the outer peripheral surface. The first inner cutting edge is positioned closer to the rear end of the cutting section than the inner end of the first outer cutting edge.

A ridgeline between the thinning face and the flank face includes a first thinning portion contiguous to the outer cutting edge, and a second thinning portion contiguous to the first thinning portion. When viewed in a direction along the central axis, the first thinning portion is linear and the second thinning portion is curved. When viewed in the direction along the central axis, the first thinning portion, and a boundary between the first thinning portion and the second thinning portion are located rearward in a rotational direction relative to a first straight line, and are located forward in the rotational direction relative to a second straight line, the first straight line being a straight line passing through the central axis and parallel to the first thinning portion, and the second straight line being a straight line perpendicular to the first straight line.

A general-purpose multiple-cutting edge drill includes: a drill point (1); a drill body (2); margins (3) located on an outer wall of the drill body (2); two lips, wherein, if viewed from an axial direction, from out to inside, each of the two lips successively includes an outer cutting edge (11), an arc cutting edge (12) and an inner cutting edge (13); a chisel edge (14); outer peaks (15) formed by intersection of the outer cutting edges (11) and the arc cutting edges (12); a center peak (16) formed by intersection of two inner flank surfaces and two split surfaces. Moreover, an included angle between the inner cutting edges (13) ranges from 108 to 128, an included angle between the outer cutting edge (11) ranges from 130 to 140, and an included angle between the inner cutting edge (13) and outer cutting edge (11) ranges from 28 to 40.