Impact tool
AssigneeMakita Corporation
InventorsHiroki Ikuta, Yoshitaka Machida, Masanori Furusawa
Life of this patent
Estimating the term…
Abstract
An electrical hammer (100) comprises a main housing (101), a hand grip (500) connected to the main housing (101) via a compression coil spring (321). In the electrical hammer (100), a hammer bit (119) is driven by a first motion converting mechanism (120) and thereby a hammering operation is performed. During the hammering operation, the hand grip (500) is moved against the main housing (101) in a state that biasing force of the compression coil spring (321) is applied on the hand grip (500). Further, the electrical hammer (100) comprises a second motion converting mechanism (220) which drives a counterweight (231).
Claims18
An impact tool which drives a tool bit in a longitudinal direction of the tool bit and performs a predetermined operation, comprising:
- a motor which includes a motor shaft,
- a driving mechanism which is driven by the motor and drives the tool bit,
- a main housing which houses the driving mechanism,
- a handle which includes a grip portion extending in a cross direction crossing the longitudinal direction of the tool bit, the handle being configured to be moved with respect to the main housing,
- a biasing member which is arranged between the main housing and the handle and applies biasing force on the handle,
- a weight which is housed in the main housing and movable with respect to the main housing,
- a first crank mechanism which has a first rotation shaft and a first eccentric shaft which is offset from the rotational center of the first rotation shaft, the first crank mechanism being configured to be driven by the motor and drive the driving mechanism, and
- a second crank mechanism which has a second rotation shaft and a second eccentric shaft which is offset from the rotational center of the second rotation shaft, the second crank member being configured to be driven by the motor and drive the weight such that the weight is relatively moved with respect to the main housing,
- wherein the weight is configured to reduce vibration generated on the main housing during the operation by relatively moving with respect to the main housing,
- the handle is configured to prevent vibration transmission from the main housing to the handle during the operation by relatively moving with respect to the main housing in a state that the biasing force of the biasing member is applied on the handle, and
- the first and second eccentric shafts are disposed such that when the first eccentric shaft is positioned at the closest position to the tool bit in the longitudinal direction of the tool bit within its movable range, the second eccentric shaft is positioned at a position other than the closest position to the tool bit in the longitudinal direction of the tool bit and the most distant position from tool bit in the longitudinal direction of the tool bit within its movable range.
An impact tool which drives a tool bit in a longitudinal direction of the tool bit and performs a predetermined operation, comprising:
- a motor which includes a motor shaft,
- a driving mechanism which is driven by the motor and drives the tool bit,
- a main housing which houses the driving mechanism,
- a handle which includes a grip portion extending in a cross direction crossing the longitudinal direction of the tool bit, the handle being configured to be moved with respect to the main housing,
- a biasing member which is arranged between the main housing and the handle and applies biasing force on the handle,
- a weight which is housed in the main housing and movable with respect to the main housing,
- a first crank mechanism which has a first rotation shaft and a first eccentric shaft which is offset from the rotational center of the first rotation shaft, the first crank mechanism being configured to be driven by the motor and drive the driving mechanism,
- a second crank mechanism which has a second rotation shaft and a second eccentric shaft which is offset from the rotational center of the second rotation shaft, the second crank member being configured to be driven by the motor and drive the weight such that the weight is relatively moved with respect to the main housing, and
- an outer housing which covers at least a part of a region of the main housing which houses the driving mechanism and the motor,
- wherein the weight is configured to reduce vibration generated on the main housing during the operation by relatively moving with respect to the main housing,
- the handle is configured to prevent vibration transmission from the main housing to the handle during the operation by relatively moving with respect to the main housing in a state that the biasing force of the biasing member is applied on the handle, and
- the handle is connected to the outer housing and integrally moved with the outer housing with respect to the main housing.
Dependencies are inferred from the claim text.