Rotary disconnect for a rotary hammer tool

Claim 2

In a rotary hammer power tool of the type having an output member in the form of a tappet which is adapted to be subjected to rotation and to axial hammering blows simultaneously, the improvement comprising: a. said tappet having a first set of clutch teeth and oppositely extending, centrally disposed, first and second hammering formations; b. a rotary tool bit driver and wall means mounting the same for rotation coaxially with said tappet, said wall means also permitting axial reciprocal movement of said driver, which driver has a centrally disposed, axial, through bore and a second set of clutch teeth adapted for engagement with said first set of clutch teeth thereby to permit said tappet to transfer rotation to said driver; c. a tool element having a shank received in said bore of said driver with the distal end thereof in abutting engagement with said first hammering formation thereby permitting the tappet to impart hammering blows to the tool element; d. connection means on said driver and said shank for transferring rotation of the former to the latter and permitting axial reciprocal movement of said driver relative to said tool element and vice versa; e. selection means engaged with said driver for reciprocating the same axially thereby to engage and disengage said first and second sets of clutch teeth for selectively imparting rotation to said driver and to the tool element therein; f. said power tool having a reciprocal hammering element arranged to engage said second hammering formation thereby to impart hammering blows to said tappet; g. other wall means rotatably mounting said tappet and including an abutment surface; and h. said tappet having an abutment element arranged to abut said abutment surface thereby to establish the forwardmost position of said tappet, which tappet is out of the range of the movement of said hammering element when the former is in said forwardmost position thereof, said tappet being moved inwardly and into the range of movement of said hammering element by the engagement of the distal end of said shank with said first hammering formation.

Claim 3

The improvement according to claim 1 further defined by, said first and second clutch teeth engaging each other only at respective surfaces contained in planes radially disposed with respect to the axis of rotation of said tappet and driver, the surfaces on said first clutch teeth being slidably engaged with the surfaces on said second clutch teeth whereby said tappet transfers rotational forces only to said driver.

Claim 4

The improvement according to claim 1 wherein said connection means are defined by a multi-surface configuration of said bore and a correspondingly shaped cross-section of the shank of said tool element.

Claim 5

The improvement according to claim 1 wherein said selection means includes a manually operated rotary member mounted by said wall means and having a pin eccentric with respect to the center of rotation thereof, and scotch-yoke means on said driver and engaged with said pin.

Claim 6

In a rotary hammer power tool of the type having a motor and a drive train for rotating a nose member and for actuating a hammering mechanism, the improvement comprising: a. a tappet and first wall means rotatably mounting the same in co-axial relationship with said nose member; b. first connection means on said nose member and said tappet for transferring rotation of the former to the latter; c. said tappet having a first hammering formation cooperating with said hammering mechanism such that the tappet is subjected to simultaneous hammering and rotation in one axial position and to rotation only in another axial position; d. abutment means adjacent said first wall means and adapted to be engaged by said tappet thereby to limit axial movement of the latter and to establish said positions of the tappet; e. said tappet having a second hammering formation and a first clutch formation; f. a rotary tool bit driver and second wall means mounting the same for rotation co-axially with said tappet, other abutment means permitting limited axial movement of said driver; g. said driver having a centrally disposed, axial, through bore and a second clutch formation arranged for engagement with said first clutch formation thereby to permit said tappet to transfer rotation to said driver; h. a tool element having a shank received in said bore of said driver with the distal end thereof in abutting engagement with said second hammering formation on the tappet thereby to allow alternate positioning of the tappet in said positions thereof and to allow the transmission of hammering blows from the tappet to the tool element when the former occupies said one axial position thereof; i. second connection means on said driver and on said shank for transferring rotation of the former to the latter and permitting axial movement of the driver relative to the tool element and vice versa; and j. selection means engaged with said driver for shifting the same axially thereby to engage and disengage said first and second clutch formations for selectively imparting rotation to said driver and to the tool element therein.

Claim 7

In a rotary hammer power tool of the type having a motor and a drive train for rotating a nose member and for actuating a hammering mechanism, the improvement comprising: a. a tappet and first wall means rotatably mounting the same in co-axial relationship with said nose member; b. first connection means on said nose member and said tappet for transferring rotation of the former to the latter; c. said tappet having a first hammering formation cooperating with said hammering mechanism such that the tappet is subjected to simultaneous hammering and rotation in one axial position and to rotation only in another axial position; d. abutment means adjacent said first wall means and adapted to be engaged by said tappet thereby to limit axial movement of the latter and to establish said positions of the tappet; e. said tappet having a second hammering formation and a first clutch formation; f. a rotary tool bit driver and second wall means mounting the same for rotation co-axially with said tappet, other abutment means permitting limited axial movement of said driver; g. said driver having a centrally disposed, axial, through bore and a second clutch formation arranged for engagement with said first clutch formation thereby to permit said tappet to transfer rotation to said driver; h. a tool element having a shank received in said bore of said driver with the distal end thereof in abutting engagement with said second hammering formation on the tappet thereby to allow alternate positioning of the tappet in said positions thereof and to allow the transmission of hammering blows from the tappet to the tool element when the former occupies said one axial position thereof; i. second connection means on said driver and on said shank for transferring rotation of the former to the latter and permitting axial movement of the driver relative to the tool element and vice versa; and j. selection means engaged with said driver for shifting the same axially thereby to engage and disengage said first and second clutch formations for selectively imparting rotation to said driver and to the tool element therein.