7  EP 3 800 013 A1 8  the top handle 40 with the right hand, the lock release lever 43b is pushed down with the palm, and the lock of the trigger lever 43a is released. Further, the operator places the pad of the thumb of the right hand, with which the gripping part 43 is gripped, on the thumb rest 45 in FIG.2 so thatthe operatorcan stably holdthe tophandle 40. 5 the axis P running through the centers in the lateral di- rection of the battery part 12 and the battery 90 is posi- tioned on the axis line L. [0057] When the operator grips the top handle 40 with the right hand and moves the chain saw 1A slightly far from the operator to cut an object relatively far from the operator,or,raisesthe chainsaw 1A slightlyupward from the operator to cut an object relatively upward from the operator,the operator slightlyextends the right arm from the top handle 40 toward the rear of the body case 10. [0050] Next, the operator shifts the thumb of the right hand to the right side to push the power switch 46 so as to be in an on-state. The pad of the thumb of the right handisthen returnedto thethumbrest 45, and whenthe trigger lever 43a is pulled up with the index finger of the right hand, as shown in FIG. 1, the motor 30 is driven to rotate the saw chain 22. As a result, the object to be cut can be cut with the saw chain 22. 10 15 [0058] In this case, the palm gripping the top handle 40 or wrist of the right hand is placed on the inclined surface 13c formed on the upper end part of the corner at the front right of the holding part 13 of the battery part 12. Thus,the palm orwristof the right hand is positioned leftward with respect to the right side surface 13b of the holding part 13. [0051] As shownin FIG.4,the chain saw 1A ofthe first embodiment includes, behind the top handle 40, a first interference reduction part 100, a second interference reduction part200,and a third interference reductionpart 300 to reduce interference with the palm holding the top handle 40 or the wrist. 20 [0059] Further, the palm holding the top handle 40 or the wrist of the right hand is placed in the recess 90c formed in the upper part of the corner at the front right of the battery 90. Thus, the palm or wrist of the right hand ispositioned leftwardwithrespectto the rightside surface 90b of the battery 90. [0052] The first interference reduction part 100 formed such that an upper end part of a part facing a front surface 90a of the battery 90 is positioned lower than an upper edge part of the rear end part 42 of the top handle 40 at a corner between the front surface 13a and a right side surface 13b of the holding part 13 of the battery part 12. An upper end part of the corner between the front surface 13a and right side surface 13b of the holding part 13 is formed with an inclined surface 13c graduallyreduced inheightfroman innerside toan outer side in the lateral direction. [0060] Further, the chain saw 1A has the axis P, run- ning through the centers in the lateral direction of the battery part 12 and the battery 90, which is positioned leftward with respect to the center in the lateral direction of the gripping part 43 of the top handle 40. Thus, the palm or wrist of the right hand can be shifted leftward. [0061] As shown in FIG. 2, the chain saw 1A (electric powerworkdevice)described above includesthe battery part 12 and the battery 90 shifted leftward. Therefore, when the operator moves the chain saw 1A relatively far away from the operator, or, when the operator raises the chain saw 1A relatively upward, the palm or wrist of the right hand is easily moved leftward. As a result, the op- erator easily extends the right arm rearward from the body case 10. [0053] The second interference reduction part 200 is formed such that a recess 90c is formed, with respect to the front surface 90a of the battery 90, on an upper part of the front surface 90a of the battery 90 at a corner be- tween the front surface 90a and a right side surface 90b of the battery 90. 35 40 [0062] Thus, with the chain saw 1A, the interference between the palm grippingthe top handle 40 orthe wrist, and the batterypart12 as wellas thebattery90 isreduced during operation so that the degree of freedom of the hand movement is increased. [0054] An upper end part of the corner between the frontsurface 90a and rightside surface 90b ofthe battery 90 is formed with an inclined surface 90d gradually re- duced in height from an inner side to an outer side in the lateral direction. The inclined surface 90d of the battery 90 is formed to continue to a rear part of the incli ned surface 13c of the holding part 13. 45 [0063] Further, as shown in FIG. 1, the chain saw 1A accommodates the motor 30 in the front part of the body case 10 and the battery 90 increased in size can mounted in the rear part so that the weight balance be- tweenthe frontand rearofthechain saw 1A isincreased. [0064] Accordingly, with the chain saw 1A of the first embodiment, the handling during operation and working efficiency are improved. [0055] As shown in FIG. 2, the third interference re- duction part300 ispositioned such thatan axisP running through the centers in the lateral direction of the battery part 12 and the battery 90 is positioned leftward with re- spect to an axis L in the longitudinal direction running through the center in the lateral direction of the gripping part 43 of the top handle 40. [0056] The battery part 12 and the battery 90 greatly protrudemore leftwardthan rightward withrespecttothe gripping part 43 of the top handle 40. That is, an amount of protrusion of the battery part 12 and the battery 90 rightward with respect to the gripping part 43 of the top handle 40 is reduced as compared with a case where 55 50 [0065] In the chain saw 1Aofthe presentembodiment, the battery 90 is mounted in the battery part 12 such that the longitudinal direction of the battery 90 corresponds to the height direction of the body case 10. In this con- figuration,the centerofgravityofthe battery 90 is shifted frontward even ifthe battery 90is increased in size in the height direction, as compared with a casewherethe lon- 5