Single-piece crankshaft
Crankshafts for handheld power tools are provided. A crankshaft includes an input section configured to be coupled to a motive device and an output section comprising first and second engagement members. The first and second engagement members are configured to drive a first and second cutting implement, wherein the first and second engaging members are spaced apart from each other in a direction along a rotational axis of the crankshaft and in a direction transverse to the rotational axis of the crankshaft, and wherein the first and second cutting implements are each coupled to or detached from the crankshaft by translating relative to the crankshaft in a direction along the rotational axis.
1 . A handheld power tool comprising:
a first cutting implement;
a second cutting implement;
a motive device; and
a crankshaft connecting the motive device to the first and second cutting implements, the crankshaft comprising:
an input section coupled to the motive device; and
an output section comprising:
a first engaging member configured to drive the first cutting implement; and
a second engaging member configured to drive the second cutting implement;
wherein the first and second engaging members are spaced apart from each other in a direction along a rotational axis of the crankshaft and in a direction transverse to the rotational axis of the crankshaft, and
wherein the first and second cutting implements are each configured to be detached from the crankshaft by translating relative to the crankshaft in a direction along the rotational axis.
2 . The handheld power tool of claim 1 , wherein the first and second cutting implements each comprise a connecting rod defining a cavity.
3 . The handheld power tool of claim 2 , wherein the cavity of the first connecting rod has an oval cross-sectional shape, wherein the first engaging member has a circular cross-sectional shape, and wherein the cavity of the first connecting rod receives the first engaging member.
4 . The handheld power tool of claim 1 , wherein the crankshaft comprises a single-piece construction in which the input section and output section are both integrally part of a single body.
5 . The handheld power tool of claim 1 , wherein the crankshaft comprises a shoulder with a beveled edge.
6 . The handheld power tool of claim 5 , wherein the shoulder extends a circumferential distance around an axis extending parallel with the rotational axis, and wherein the circumferential distance is less than 270°.
7 . The handheld power tool of claim 1 , wherein the power tool further comprises a bearing assembly coupled to the input section of the crankshaft.
8 . The handheld power tool of claim 1 , wherein translating the first and second cutting implements in the direction comprises translating the second cutting implement less distance than the first cutting implement.
9 . The handheld power tool of claim 1 , wherein the first and second cutting implements are slidably coupled together by a bushing spaced apart from the crank shaft, and wherein the bushing is configured to maintain the first and second cutting implements in alignment with the first and second engaging members, respectively.
10 . The handheld power tool of claim 1 , wherein the crankshaft comprises a spacing member disposed adjacent to both the first and second engaging members, wherein the spacing member contacts both the first and second cutting implements.
11 . The handheld power tool of claim 1 , wherein the first and second engaging members are configured to convert rotational motion of the crankshaft about the rotational axis to linear motion of the first and second cutting implements.
12 . The handheld power tool of claim 1 , wherein the handheld power tool is a hedge trimmer.
13 . A handheld power tool comprising:
a first cutting implement;
a second cutting implement;
a motive device; and
a crankshaft connecting the motive device to the first and second cutting implements, the crankshaft comprising:
an input section coupled to the motive device; and
an output section comprising:
a first engaging member configured to drive the first cutting implement; and
a second engaging member configured to drive the second cutting implement;
wherein the first and second engaging members are spaced apart from each other in a direction along a rotational axis of the crankshaft and in a direction transverse to the rotational axis of the crankshaft,
wherein the input section of the crankshaft is spaced apart from the first and second engaging members, and
wherein the crankshaft comprises a single-piece construction in which the input section and output section are both integrally part of a single body.
14 . The handheld power tool of claim 13 , wherein the first and second cutting implements each comprise a connecting rod defining a cavity.
15 . The handheld power tool of claim 14 , wherein the cavity of the first connecting rod has an oval cross-sectional shape, wherein the first engaging member has a circular cross-sectional shape, and wherein the cavity of the first connecting rod receives the first engaging member.
16 . The handheld power tool of claim 13 , wherein the crankshaft comprises a shoulder with a beveled edge.
17 . The handheld power tool of claim 16 , wherein the shoulder extends a circumferential distance around an axis extending parallel with the rotational axis, and wherein the circumferential distance is less than 270°.
18 . The handheld power tool of claim 13 , wherein the power tool further comprises a bearing assembly coupled to the input section of the crankshaft.
19 . The handheld power tool of claim 13 , wherein translating the first and second cutting implements in the direction comprises translating the second cutting implement less distance than the first cutting implement.
20 . The handheld power tool of claim 13 , wherein the crankshaft comprises a spacing member disposed adjacent to both the first and second engaging members, wherein the spacing member contacts both the first and second cutting implements.