37. A portion of the pad 31 located between the corner portions 34 and 36 will also be referred to as a side edge portion 38. A portion of the pad 31 located between the corner portions 35 and 36 will also be referred to as a side edge portion 39. The base 32 has a shape and a size corresponding to the outer shape of the pad 31 and also slightly smaller than the pad 31 as viewed vertically.

As illustrated in FIGS. 1, 2, 5, and 6, an inclination angle of the side surface of the pad 31 with respect to the flat surface 33 varies depending on the location. More specifically, the inclination angle of a first portion 40, which is the side surface of the corner portion 34, is a first angle θ1 (refer to FIG. 5). Further, the inclination angle of a second portion 41 of the side surface of the side edge portion 37 that is located adjacent to the corner portion 35 is a second angle θ2 (refer to FIG. 6). Similarly, the inclination angle of a second portion 41 of the side surface of the side edge portion 38 that is located adjacent to the corner portion 36 is the second angle θ2 (refer to FIG. 6). In the present embodiment, the first angle θ1 is approximately 80°, and the second angle θ2 is approximately 35°. However, the first angle θ1 and the second angle θ2 can be set to any angle as long as they satisfy 90°≥θ1>θ2>0°. A transition portion 42 is located between the first portion 40 and the second portion 41 on each of the side edge portion 37 and the side edge portion 38. Each transition portion 42 connects the first portion 40 and the second portion 41 in such a manner that the inclination angle of the side surface of the pad 31 gradually changes from the first angle θ1 to the second angle θ2.

In the present embodiment, when H is defined to represent the vertical thickness of the pad 31 and L is defined to represent the protruding distance of a distal edge 46 from a proximal edge 45 of the inclination of the second portion 41 as illustrated in FIG. 6, a ratio L/H is set to any value equal to or higher than 0.5 and equal to or lower than 2.5.

As illustrated in FIGS. 1, 2, and 6, a side surface 47 of the base 32 is inclined in the same direction as the pad 31 at least on a portion corresponding to the second portion 41 in the present embodiment. In the present embodiment, the inclination angle of the side surface 47 varies in conformity with the change in the inclination angle of the side surface of the pad 31 from the first portion 40 to the second portion 41. Further, in the present embodiment, the inclination angle of the second portion 41 of the pad 31 is smaller than the inclination angle of the side surface 47 of the base 32.

As illustrated in FIGS. 4 and 5, a plurality of through-holes 43 is formed on the bottom surface of the pad 31. The through-holes 43 vertically extend through the pad 31. A space 44 (refer to FIG. 5) is defined between the pad 31 and the base 32. The space 44 is in communication with the through-holes 43. The space 44 is in communication with the dust collection passage 28. Holes are formed on the sanding paper attached to the bottom surface of the pad 31 at positions corresponding to the through-holes 43 of the pad 31. When the dust collection fan 50 rotates according to the rotation of the motor shaft 61, air flows into the dust bag 100 by passing through the holes of the sanding paper, the through-holes 43, the space 44, and the dust collection passage 28. Dust generated due to the sanding can be collected into the dust bag 100 with the aid of this flow of air.

As illustrated in FIG. 5, the bearing 64 is fixed to the tool accessory 30. The bearing 64 supports the shaft portion 52 of the dust collection fan 50. Therefore, the tool accessory 30 is coupled with the motor shaft 61 via the bearing 64 and the dust collection fan 50. Further, the tool accessory 30 is further coupled operably with the front housing portion 21 via a vertically extending foot 66. The foot 66 is disposed at each of the front portion and the rear portion of the front housing portion 21.

The above-described sander 10 operates in the following manner. First, when the user operates the switch button 27 to drive the electric motor 60, the motor shaft 61 starts rotating. At this time, the bearing 64 coupling the motor shaft 61 and the tool accessory 30, and the shaft portion 52 of the dust collection fan 50 are eccentric with respect to the motor shaft 61 as described above. Therefore, when the motor shaft 61 rotates, the tool accessory 30 performs an eccentric circular motion (an orbital motion) while tilting the foot 66. In other words, the tool accessory 30 does not rotate itself, and moves so as to draw a circle along a horizontal surface while maintaining this posture. When the sanding paper attached to the flat surface 33 of the pad 31 is pressed against a machining target in this state, the sanding is performed.

According to the above-described sander 10, the user can selectively use the first portion 40 and the second portion 41 of the pad 31 inclined at different angles according to use conditions of the sanding work (i.e., according to what kind of region is sanded in the machining target).

For example, when sanding a narrow small machining target region, the user may sand it by pressing only the corner portion 34 with the first portion 40 formed thereon against the machining target region. The first portion 40 is inclined at a relatively large angle and is relatively high in rigidity. Therefore, even when the machining target is sanded with only a small region in the pad 31 pressed against it and a concentrative reaction force is applied only to a part of the pad 31, the pad 31 can sufficiently withstand the reaction force. In addition, because the first portion 40 is formed at the corner portion 34, even when a narrow machining target region in the machining target is sanded, the portion with the first portion 40 formed thereon (i.e., the corner portion 34) can be easily advanced into this machining target region. Especially, because being located at the distal edge of the triangular pad 31, the corner portion 34 can be easily advanced into the narrow machining target region in the machining target. Further, because having an angle equal to or smaller than 90° in a planar view, the corner portion 34 can be easily advanced into the narrow machining target region in the machining target.

Alternatively, when sanding a machining target region that imposes a constraint on an entry height (a distance in the direction perpendicular to a machining target surface) of the pad 31 (for example, a gap between a hinge attached to a machining target and the machining target), the user may sand it by pressing only the side edge portion 37 with the second portion 41 formed thereon (or the side edge portion 37 with the transition portion 42 and the second portion 41 formed thereon) against the machining target region. The second portion 41 is inclined at a relatively small angle, and therefore can be advanced into the machining target region that imposes a constraint on the entry height of the pad 31. Especially, the second portion 41 is formed on each of the side edge portions 37 and 38 between the corner portion 34 and the corner portions 35 and 36, and therefore can be used to efficiently sand a wide range. In addition, the user can sand the machining target region while moving the housing 20 in the direction in which the grip portion 22 extends with the second portion 41 advanced into the machining target region that imposes a constraint on the entry height of the pad 31, and therefore can engage in the sanding work with a natural arm posture and movement. Especially, the second portion 41 has the ratio L/H equal to or higher than 0.5 and equal to or lower than 2.5, and therefore can be easily advanced into the machining target region that imposes a constraint on the entry height of the pad 31. Further, in addition to the pad 31, the side surface 47 of the base 32 is also inclined in the same direction as the pad 31, and therefore the second portion 41 can be further deeply advanced into the machining target region that imposes a constraint on the entry height of the pad 31. Further, the inclination angle of the second portion 41 of the pad 31 is smaller than the inclination angle of the side surface 47 of the base 32, and therefore the second portion 41 can be further easily advanced.

Further, according to the sander 10, the transition portion 42 is formed between the first portion 40 and the second portion 41 of the pad 31, and therefore the concentration of a local stress on the pad 31 can be reduced. As a result, the pad 31 can be improved in strength. Similarly, the side surface 47 of the base 32 is also inclined at a gradually varying angle, and therefore the base 32 can be improved in strength.

In the following description, the configuration of the dust bag 100 detachably mounted on the dust collection nozzle 29 will be described with reference to FIGS. 7 to 11. Direction indicators in FIGS. 7 to 11 indicate directions with the dust bag 100 mounted on the dust collection nozzle 29. As illustrated in FIG. 7, the dust bag 100 includes a bag main body 110, a connector 120, and a frame 130. The bag main body 110 is made of cloth. The connector 120 is a portion for detachably connecting to the dust collection nozzle 29 of the sander 10, and has a generally cuboidal outer shape in the present embodiment. The connector 120 includes a through-hole 121 opened in the first direction D1. The through-hole 121 is in communication with the inside of the bag main body 110. The through-hole 121 is sized and shaped so as to be fitted to the dust collection nozzle 29.

The first direction D1 is also a direction in which the dust collection nozzle 29 is opened as illustrated in FIG. 3 with the dust bag 100 mounted on the dust collection nozzle 29. In other words, the first direction D1 is a direction inclined slightly upward from the front side toward the rear side with respect to the front-rear direction. As illustrated in FIG. 7, in the present embodiment, the bag main body 110 is kept generally shaped like a cuboid rectangular in cross-section in a direction perpendicular to the first direction D1 with the aid of the frame 130 disposed inside the bag main body 110. In the following description, the longer-side direction of this rectangle will also be referred to as a third direction D3, and the shorter-side direction of the rectangle will also be referred to as a second direction D2. The second direction D2 is a direction inclined slightly forward from the lower side toward the upper side with respect to the vertical direction. The third direction D3 matches the left-right direction.

According to the bag main body 110 shaped in this manner, the bag main body 110 can be configured vertically compactly. As a result, the sander 10 can be configured vertically compactly with the bag main body 110 mounted thereon. Especially, in the present embodiment, the power source cord 26 extends above the bag main body 110 with the bag main body 110 mounted, but the bag main body 110 is shaped so as to be relatively narrow in width in the second direction D2, and therefore the sander 10 can be configured vertically compactly while the interference is avoided between the power source cord 26 and the bag main body 110.

As illustrated in FIG. 10, the frame 130 includes a plurality (ten in the illustrated example) of non-flexible portions 131, a plurality (four in the illustrated example) of non-flexible portions 133, and a plurality (16 in the illustrated example) of flexible portions 134. Each of the non-flexible portions 131 extends in the second direction D2 perpendicular to the first direction D1 so as to have no flexibility in the first direction D1. In the present embodiment, the five non-flexible portions 131 are disposed so as to be spaced apart from the other five non-flexible portions 131 in the left-right direction (the third direction D3 perpendicular to the first direction D1). The non-flexible portions 131 disposed on the left side will also be referred to as first-side non-flexible portions 131a. The non-flexible portions 131 disposed on the right side will also be referred to as second-side non-flexible portions 131b. The five first-side non-flexible portions 131a are lined up in the first direction D1 at intervals from each other. Similarly, the five second-side non-flexible portions 131b are lined up in the first direction D1 at intervals from each other. The first-side non-flexible portions 131a and the second-side non-flexible portions 131b are disposed at the same positions in the first direction D1 in the present embodiment, but may be disposed at different positions.

The upper end and the lower end of the first-side non-flexible portion 131a located at the foremost side and the upper end and the lower end of the second-side non-flexible portion 131b located at the foremost side are respectively coupled with each other via the two non-flexible portions 133 extending in the third direction D3 perpendicular to the first direction D1. Similarly, the upper end and the lower end of the first-side non-flexible portion 131a located at the rearmost side and the upper end and the lower end of the second-side non-flexible portion 131b located at the rearmost side are respectively coupled with each other via the two non-flexible portions 133 extending in the third direction D3.

The flexible portions 134 are coupled with the non-flexible portions 131, and extend in a direction intersecting with the first direction D1 and the second direction D2 so as to have flexibility in the first direction D1. In the present embodiment, the non-flexible portions 131 and the flexible portions 134 are disposed alternately along the first direction D1. Further, in the present embodiment, the flexible portions 134 include first-side flexible portions 134a, which are disposed on the left side and coupled with the first-side non-flexible portions 131a, and second-side flexible portions 134b, which are disposed on the right side and coupled with the second-side non-flexible portions 131b.

In the present embodiment, the flexible portions 134 each have a shape of a triangle wave pulse (i.e., a V-like shape). More specifically, the first-side flexible portion 134a located on the left side extends from one first-side non-flexible portion 131a rightward (toward the right side where the second-side non-flexible portion 131b is located), and is also bent back in a V-shaped manner to extend to the adjacent first-side non-flexible portion 131a. The second-side flexible portion 134b located on the right side extends from one second-side non-flexible portion 131b leftward (toward the left side where the first-side non-flexible portion 131a is located), and is also bent back in a V-shaped manner to extend to the adjacent second-side non-flexible portion 131b. The shape of the flexible portion 134 can be changed to any pulse shape (for example, a circular arc-shaped pulse or a sawtooth wave pulse).

The first-side flexible portions 134a include first-side flexible portions 134a disposed on the upper side and coupled with the upper ends of the first-side non-flexible portions 131a, and first-side flexible portions 134a disposed on the lower side and coupled with the lower ends of the first-side non-flexible portions 131a. Similarly, the second-side flexible portions 134b include second-side flexible portions 134b disposed on the upper side and coupled with the upper ends of the second-side non-flexible portions 131b, and second-side flexible portions 134b disposed on the lower side and coupled with the lower ends of the second-side non-flexible portions 131b.

In the present embodiment, the first-side flexible portions 134a and the second-side flexible portions 134b are coupled with each other. More specifically, each of the first-side flexible portions 134a includes a first distal edge portion 136 located at the tip of the pulse shape thereof (the vertex of the V shape). Similarly, each of the second-side flexible portions 134b includes a second distal edge portion 137 located at the tip of the pulse shape thereof. The first distal edge portion 136 and the second distal edge portion 137 are coupled with each other in the third direction D3 (i.e., a direction in which the first-side non-flexible portion 131a and the second-side non-flexible portion 131b are spaced apart from each other).

A tubular fitted portion 138 protrudes forward in the first direction D1 from the non-flexible portions 131 located at the foremost side and the non-flexible portions 133 on the front side. As illustrated in FIG. 8, the fitted portion 138 is fitted in the connector 120 and is screwed to the connector 120 in this state. Due to that, the frame 130 is coupled with the connector 120. Further, in such a coupled state, the front edge portion of the bag main body 110 is fitted on the outer periphery of the rear edge portion of the connector 120, and a band 111 is attached so as to surround the bag main body 110 circumferentially (the second direction D2 and the third direction D3), as illustrated in FIGS. 8 and 9. As a result, the bag main body 110 is tightened inward by the band 111, and the bag main body 110 is coupled with the connector 120 and the frame 130.

At this time, the first-side non-flexible portions 131a and the second-side non-flexible portions 131b provide an outward tension to the bag main body 110 in the left-right direction in abutment with the inner surface of the bag main body 110. Due to that, the width of the bag main body 110 in the third direction D3 is kept equal to the distance by which the first-side non-flexible portions 131a and the second-side non-flexible portions 131b are spaced apart from each other. Further, as illustrated in FIG. 9, the non-flexible portions 131 extend over most of the width of the bag main body 110 in the second direction D2, and therefore the width of the bag main body 110 in the second direction D2 is prevented from considerably reducing due to a sag or deflection of the bag main body 110. Therefore, the frame 130 can keep the outer shape of the bag main body 110 generally cuboidal as illustrated in FIG. 7. As a result, the bag main body 110 is prevented from sagging to get in the way of the user during the sanding work.

In the present embodiment, the frame 130 structured in the above-described manner is made from synthetic resin. Therefore, even though the frame 130 is relatively complicatedly structured as described above, the frame 130 can be easily manufactured. Further, the frame 130 can be reduced in weight. However, the frame 130 can be manufactured from any material. Further, in the present embodiment, the frame 130 is an integrally formed member (one-piece member). Therefore, the frame 130 can be manufactured with a smaller number of processes. However, the frame 130 may be manufactured by bonding or mechanically joining two or more members.

According to the above-described dust bag 100, the frame 130 can be extended or compressed in the first direction D1 due to the flexible portions 134 deflected when an external force is applied in the first direction D1. Therefore, the user can extend and compress the bag main body 110 together with the frame 130 by pressing the bag main body 110 in the first direction D1 with his/her hand when detaching the dust bag 100 from the dust collection nozzle 29 and carrying out the work of discharging dust accumulated in the dust bag 100. This can facilitate the discharge of the dust deposited on the inner surface of the bag main body 110 via the through-hole 121. Further, the frame 130 can provide the extension and compression function in the first direction D1 while keeping the outer shape of the bag main body 110 generally cuboidal in contrast to a coil spring.

In addition, in the present embodiment, as illustrated in FIG. 11, the total width of the flexible portions 134 in the first direction D1 (L21+L22+L23+L24 in FIG. 11) is equal to or longer than the total width of the non-flexible portions