An impact tool enables a front cover part to be easily attached to and detached from a housing body, with a device having a simplified structure. The front cover part has an annular fastening portion clamped to the outer peripheral surface of a front edge portion of the housing body, a cylindrical p
An impact tool enables a front cover part to be easily attached to and detached from a housing body, with a device having a simplified structure. The front cover part has an annular fastening portion clamped to the outer peripheral surface of a front edge portion of the housing body, a cylindrical portion extending from the front end of the housing to the region of the fastening portion, and a connecting portion connecting together the cylindrical portion and the fastening portion. The fastening portion is split at a circumferential part thereof to form a pair of circumferentially opposing tongue-shaped portions. A clamping device is provided between the tongue-shaped portions, which is movable between a clamping position where it pulls the tongue-shaped portions toward each other and an unclamping position where the tongue-shaped portions are released from being pulled toward each other.
대표청구항▼
What is claimed is: 1. An impact tool comprising: an impact tool assembly including a reciprocating ram, an anvil positioned forward of said ram to receive an impact force from said ram, a needle chisel holder for carrying needle chisels longitudinally and movably, and for receiving the impact forc
What is claimed is: 1. An impact tool comprising: an impact tool assembly including a reciprocating ram, an anvil positioned forward of said ram to receive an impact force from said ram, a needle chisel holder for carrying needle chisels longitudinally and movably, and for receiving the impact force from said ram through said anvil, and a cylinder that accommodates said ram, anvil and needle chisel holder in coaxial alignment with one another; a cylindrical housing slidably retaining said impact tool assembly; and a grip extending outward from one side of said housing, said grip being adapted to be held by an operator; wherein said cylinder has a small-diameter portion extending axially along an outer peripheral surface of said cylinder through a predetermined length, said small-diameter portion having a front end and a rear end, said cylindrical housing having a spring engaging portion provided on an inner peripheral surface thereof, said cylindrical housing further having a spring retainer provided at a rear end thereof, wherein a first coil spring is set between the front end of said small-diameter portion of said cylinder and the spring engaging portion of said cylindrical housing, and a second coil spring is set between the rear end of said small-diameter portion and said spring engaging portion, and a third coil spring is set between a rear end of said impact tool assembly and the spring retainer at the rear end of said cylindrical housing, said first and second coil springs being adapted to floatingly support said impact tool assembly in an axial direction of said cylindrical housing, said third coil spring being adapted to receive a substantial part of reaction force acting on said impact tool assembly when tips of the needle chisels are pressed against a workpiece to perform a desired operation. 2. An impact tool according to claim 1, wherein said grip extends obliquely rearward from said cylindrical housing, said grip having: an air inlet provided in a distal end portion of said grip, said air inlet being adapted to be connected to an air hose for supplying compressed air to drive the ram of said impact tool assembly, and an air outlet for the compressed air; and a compressed air inlet passage provided in said grip to guide compressed air supplied through said air inlet to said impact tool assembly, and an air outlet passage provided in said grip to lead compressed air having been used to drive said ram to said air outlet. 3. An impact tool according to claim 2, wherein a chamber is provided between said cylinder and said needle chisel holder to receive compressed air for retracting said needle chisel holder, and a pipe is integrally cast in said grip, said pipe opening at a rear end thereof into said compressed air inlet passage and extending forward therefrom, said pipe being communicated with said chamber at a front end portion thereof. 4. An impact tool according to claim 1, wherein a thermal insulating covering material is provided around said grip. 5. An impact tool according to claim 1, wherein the outer peripheral surface of said cylinder has a small-diameter portion extending from a rear end of said cylinder toward a front end thereof, and a large-diameter portion extending forward from said small-diameter portion, and said cylinder has a rear plug detachably fitted into the rear end thereof to close said rear end to form a compressed air chamber between said rear plug and said ram, said spring engaging portion of said housing being formed by an annular member secured to a predetermined position on an inner surface of said housing, said annular member having at a front end thereof a first spring fitting portion inserted into a rear end portion of said first coil spring to retain said rear end portion, said annular member further having at a rear end thereof a second spring fitting portion inserted into a front end portion of said second coil spring to retain said front end portion. 6. An impact tool according to claim 1, wherein said needle chisel holder is set in a distal end portion of said cylinder so as to be reciprocatable in the axial direction of said cylinder, said needle chisel holder having a large-diameter portion slidably engaged with an inner surface of said cylinder and a small-diameter portion extending forward from said large-diameter portion, wherein a stop ring is detachably fitted to an inner surface of the distal end portion of said cylinder, said stop ring being set so as to slidably engage an outer peripheral surface of the small-diameter portion of said needle chisel holder, said stop ring cooperating with the large-diameter portion and the small-diameter portion of said needle chisel holder and said cylinder to form a chamber for receiving compressed air to urge said needle chisel holder rearward of said cylinder, said stop ring being secured to the distal end portion of said cylinder so as to be immovable in the axial direction by a split wire ring set in an elastically expanded state in an annular groove formed in the inner peripheral surface of the distal end portion of said cylinder. 7. An impact tool according to claim 1, wherein said housing includes: a front cover part extending rearward from the front end of said housing; a housing body detachably connected to a rear end of said front cover part; and a clamping device that clamps said front cover part to said housing body; said front cover part having: an annular fastening portion placed on and clamped to an outer peripheral surface of a front edge portion of said housing body, thereby being connected to said outer peripheral surface; a cylindrical portion extending from the front end of said housing to a neighborhood of said fastening portion; and a connecting portion connecting together said cylindrical portion and said fastening portion; said annular fastening portion being split at a circumferential part thereof, thereby having a pair of tongue-shaped portions opposing each other circumferentially; said clamping device being provided between said tongue-shaped portions and movable between a clamping position where said clamping device pulls said tongue-shaped portions toward each other and an unclamping position where said tongue-shaped portions are released from being pulled toward each other. 8. An impact tool according to claim 7, wherein said clamping device includes: a lever member having a proximal end pivotally attached to a distal end of one of said tongue-shaped portions; and a clamping member having a first end portion pivotally attached to said lever member at a position closer to a distal end of said lever member than the proximal end of said lever member, and a second end portion engageable with the other of said tongue-shaped portions; wherein, in said clamping position, said lever member applies tension to said clamping member in a state where the second end portion of said clamping member is engaged with said other of said tongue-shaped portions, wherein said first end portion is located further away from said second end portion than the proximal end of said lever member, and an imaginary line connecting said first and second end portions passes radially inward of the proximal end of said lever member at said fastening portion, whereas in said unclamping position, in a state where the second end portion of said clamping member is engaged with said the other of said tongue-shaped portions, an imaginary line connecting said first and second end portions passes radially outward of said proximal end at said fastening portion.
Henry Edgar G. (Kirtland OH) Schossler Frank W. (Willoughby Hills OH) Kuhl Donald K. (Chesterland OH), Pneumatic impact tool having improved vibration and noise attenuation.
※ AI-Helper는 부적절한 답변을 할 수 있습니다.