RECIPROCATING WORK MACHINE
Provided is a reciprocating work machine capable of further reducing vibration transmitted from a housing to a handle. The reciprocating work machine provided with an electric motor, a piston and a striker reciprocating by power of the electric motor and striking a tool, and a housing accommodating the electric motor, the piston, and the striker, includes: a resin handle operably connected to the housing; a spring provided between the housing and the handle and expanding and contracting in a reciprocating direction of the piston and the striker when the handle operates relative to the housing; and a weight provided to the handle and made of a material having a specific gravity higher than each of a specific gravity of a material constituting the handle and a specific gravity of a material constituting the housing.
1 . A reciprocating work machine provided with a motor, a striking mechanism reciprocating by power of the motor and striking a tool, and a housing accommodating the motor and the striking mechanism, the reciprocating work machine comprising:
a resin handle operably connected to the housing;
an elastic body provided between the housing and the handle and expanding and contracting in a reciprocating direction of the striking mechanism when the handle is operated relative to the housing; and
a weight provided to the handle and made of a material having a specific gravity higher than each of a specific gravity of a material constituting the handle and a specific gravity of a material constituting the housing.
2 . The reciprocating work machine according to claim 1 ,
wherein a supporting shaft disposed along a direction orthogonal to the reciprocating direction is provided, and
the handle is connected to the housing so as to be rotatable about the supporting shaft.
3 . The reciprocating work machine according to claim 2 ,
wherein the handle includes a gripping portion disposed along the direction orthogonal to the reciprocating direction,
the gripping portion has a first end portion and a second end portion disposed at both ends in a predetermined direction crossing the reciprocating direction,
the elastic body is disposed between the first end portion and the housing,
the supporting shaft connects the second end portion to the housing, and
the weight is provided to the first end portion.
4 . The reciprocating work machine according to claim 3 ,
wherein the elastic body is a spring supported by the housing and the handle, and
the weight is fixed to the handle and supports an end portion of the spring in an expansion and contraction direction.
5 . The reciprocating work machine according to claim 1 ,
wherein a mass of the weight is set such that a vibration transmission rate in the reciprocating direction transmitted from the housing to the handle when the motor rotates at a maximum rotational number and when the handle is provided with the weight is smaller than a vibration transmission rate in the reciprocating direction transmitted from the housing to the handle when the motor rotates at the maximum rotational number and when the handle is not provided with the weight.
6 . The reciprocating work machine according to claim 5 ,
wherein the vibration transmission rate when the handle is not provided with the weight is equal to or greater than 100%, and
the vibration transmission rate when the handle is provided with the weight is less than 100%.
7 . The reciprocating work machine according to claim 1 ,
wherein the elastic body is a spring sandwiched by the housing and the handle, and
the weight is fixed to the handle and supports an end portion of the spring in an expansion and contraction direction.
8 . The reciprocating work machine according to claim 7 ,
wherein a supporting shaft orthogonal to the reciprocating direction of the striking mechanism is provided,
the handle is connected to the housing so as to be rotatable about the supporting shaft,
the weight has a first side surface and a second side surface disposed at an interval in a direction of a center line of the supporting shaft,
the housing includes a guide portion,
the guide portion has a pair of leg portions disposed along the reciprocating direction, and
the pair of leg portions slides on the first side surface and the second side surface when the handle rotates about the supporting shaft.
9 . The reciprocating work machine according to claim 7 ,
wherein the weight has a recessed portion, and
the spring is disposed in the recessed portion.
10 . The reciprocating work machine according to claim 7 ,
wherein the weight restricts a range of operation of the handle relative to the housing by abutting on the housing.
11 . The reciprocating work machine according to claim 7 , comprising:
a resin member coming in contact with the spring.
12 . The reciprocating work machine according to claim 11 ,
wherein the spring is a cylindrical coil spring, and
the resin member is accommodated inside the spring.
13 . The reciprocating work machine according to claim 12 ,
wherein the resin member is formed to be smaller than an inner diameter of the spring and is floatable inside the spring.
14 . (canceled)
15 . The reciprocating work machine according to claim 13 ,
wherein the resin member is made of rubber and has a substantially cylindrical shape in which an edge portion of an end surface on either side of a cylinder is chamfered,
an outer diameter of the resin member is smaller than the inner diameter of the spring, and
a length of the resin member in an axial direction is shorter than a distance when a spring supporting portion provided to the housing and the weight are the closest to each other.
16 . The reciprocating work machine according to claim 11 , comprising:
a plurality of the resin members arranged in the expansion and contraction direction of the spring.