Adjustable positive clutch screwdriver

Claim 2

A portable power-operated tool of the type including a rotary output tool member and means for preselecting the torque applied through said output member to a workpiece, said tool comprising a housing; motor means within said housing and including rotary output shaft means; output tool means supported by said housing; torque-transmitting clutch means within said housing including a first clutch member associated with said rotary output shaft means and a second clutch meMber associated with said tool means, said first and said second clutch members being arranged upon engagement thereof to transmit rotational torque from said output shaft means to said tool means; biasing means normally urging said first and said second clutch members to a spaced-apart position; said biasing means being adapted to be overcome upon the application of an axial force between said tool means and said housing; said first and said second clutch members each including axially extending, circumferentially facing surfaces, said surfaces on said first clutch member being arranged to engage said surfaces on said second member when said clutch members are moved into engagement; and adjustable means for limiting the maximum axial depth of engagement of said surfaces.

Claim 3

A portable power tool as claimed in claim 1 wherein each of said first and second clutch members comprises axially extending teeth, said circumferentially facing surfaces comprising complementary sides of said teeth.

Claim 4

A portable power tool as claimed in claim 1 wherein said surfaces extend outwardly from said first and said second clutch members at an angle to the axis of said clutch means.

Claim 5

A portable power tool as claimed in claim 3 wherein at least a major portion of said surfaces is positioned at an angle of 15* to said axis of said clutch means.

Claim 6

A portable power tool as claimed in claim 3 wherein each of said surfaces includes a plurality of portions, each of said portions lying at a different angle to said axis than said other portions.

Claim 7

A portable power tool as claimed in claim 5 wherein a first of said portions extends at an angle of approximately 15* to said axis, a second portion extends at an angle of approximately 45* to said axis and a third portion extends at an angle of approximately 60* to said axis.

Claim 8

A portable power tool as claimed in claim 1 wherein said clutch means comprises the sole torque-transmitting coupling means between said output shaft and said tool means to permit rotation of said output shaft without rotation of said tool means when said first and said second clutch members are disengaged.

Claim 9

A portable power operated tool adapted to be held in an operator''s hand and to provide an output torque to a workpiece only when said tool is biased against said workpiece by the operator, said tool comprising a housing including a hand grip portion; a motor within said housing having a rotary output shaft; a rotatable chuck means supported by said housing; clutch means for transmitting rotational torque from said output shaft to said chuck means upon engagement thereof, said clutch means including a first clutch member associated with said output shaft and a second clutch member associated with said chuck means; biasing means normally urging said second clutch member out of engagement with said first clutch member; complementary clutch teeth formed on and axially extending from said first and said second clutch members; said chuck means and said second clutch member being slidably mounted within said housing for axial movement toward and away from said first clutch member; and adjusting collar means threadedly engaged with said housing for limiting the axial movement of said chuck means into said housing to control the depth of engagement of said complementary clutch teeth to thereby control the maximum torque transmissible through said clutch means.

Claim 10

A portable power operated tool adapted to be held in an operator''s hand and to provide an output torque to a workpiece only when said tool is biased against said workpiece by the operator, said tool comprising a housing including a hand grip portion; a motor within said housing having a rotary output shaft; a rotatable chuck means supported by said housing; clutch means for transmitting rotational torque from said output shaft to said chuck means upon engagement thereof, said clutch means including a first clutch member associated with said output shaft and a second clutch member associated with said chuck means; biasing means normally urging said second clutch member out of engagement with said first clutch member; complementary clutch teeth formed on and axially extending from said first and said second clutch members; said chuck means and said second clutch member being slidably mounted within said housing for axial movement toward and away from said first clutch member; and adjusting collar means threadedly engaged with said housing for limiting the axial movement of said chuck means into said housing to control the depth of engagement of said complementary clutch teeth to thereby control the maximum torque transmissible through said clutch means.

Claim 11

A portable power tool comprising a housing; motor means within said housing including rotary output shaft means; rotary tool means supported by said housing; torque-transmitting clutch means within said housing for coupling said output shaft means with said tool means, said clutch means comprising complementary sets of clutch teeth respectively associated with said shaft means and said tool means; biasing means normally urging said clutch teeth to a spaced-apart position and adapted to be overcome upon engagement of said power tool with a workpiece, and adjustablE means for limiting the maximum depth of engagement of said clutch teeth.

Claim 12

A portable power tool comprising a housing; motor means within said housing including rotary output shaft means; rotary tool means supported by said housing; torque-transmitting clutch means within said housing for coupling said output shaft means with said tool means, said clutch means comprising complementary sets of clutch teeth respectively associated with said shaft means and said tool means; biasing means normally urging said clutch teeth to a spaced-apart position and adapted to be overcome upon engagement of said power tool with a workpiece, and adjustablE means for limiting the maximum depth of engagement of said clutch teeth.

Claim 13

A power tool as claimed in claim 9 wherein one of said sets of clutch teeth is axially fixed relative to said housing and wherein said adjustable means comprises a surface axially movable relative to said housing.

Claim 14

A power tool claimed in claim 10 wherein the other of said sets of clutch teeth is provided with antifriction means for engagement with said surface.

Claim 15

A portable power tool comprising a housing; motor means within said housing including rotary output shaft means; rotary tool means supported by said housing; torque-transmitting clutch means within said housing for coupling said output shaft means with said tool means, said clutch means comprising complementary sets of clutch teeth respectively associated with said shaft means and said tool means, each of said sets of clutch teeth comprising a plurality of axially extending teeth, each of said teeth having a surface engageable with a corresponding surface on a corresponding tooth in the other of said sets, each of said surfaces including a plurality of regions positioned at different angles to the axis of said sets; biasing means normally urging said clutch teeth to a spaced-apart position and adapted to be overcome upon engagement of said power tool with a workpiece; and adjustable means for limiting the maximum depth of engagement of said clutch teeth.

Claim 16

A portable power tool comprising a housing; motor means within said housing including rotary output shaft means; rotary tool means supported by said housing; torque-transmitting clutch means within said housing for coupling said output shaft means with said tool means, said clutch means comprising complementary sets of clutch teeth respectively associated with said shaft means and said tool means, each of said sets of clutch teeth comprising a plurality of axially extending teeth, each of said teeth having a surface engageable with a corresponding surface on a corresponding tooth in the other of said sets, each of said surfaces including a plurality of regions positioned at different angles to the axis of said sets; biasing means normally urging said clutch teeth to a spaced-apart position and adapted to be overcome upon engagement of said power tool with a workpiece; and adjustable means for limiting the maximum depth of engagement of said clutch teeth.

Claim 17

A power tool as claimed in claim 12 wherein a first region at the peak of said teeth is positioned at an angle of 60* relative to said axis; a second region adjacent said first region is positioned at an angle of 45* relative to said axis and a third region adjacent said second region is positioned at an angle of 15* relative to said axis.

Claim 18

A portable power tool comprising a housing; motor means within said housing and including rotary output shaft means; rotary tool means supported by said housing; adjustable clutch means within said housing and adapted to couple said output shaft means with said tool means; means for adjusting the maximum torque transmission capability of said clutch; said clutch comprising first means connected to said rotary output shaft and having a first set of clutch teeth extending axially towards said tool means, a second member connected to said tool means and including a second set of clutch teeth extending axially towards said rotary output shaft means; resilient means spacing said first and second sets of clutch teeth apart, said resilient means arranged to be overcome by operator pressure in applying said tool to a workpiece; said adjustable means comprising a stop member threadedly mounted on said housing for limiting the depth of engagement of said first and second sets of clutch teeth.

Claim 19

A portable power tool comprising a housing; motor means within said housing and including rotary output shaft means; rotary tool means supported by said housing; adjustable clutch means within said housing and adapted to couple said output shaft means with said tool means; means for adjusting the maximum torque transmission capability of said clutch; said clutch comprising first means connected to said rotary output shaft and having a first set of clutch teeth extending axially towards said tool means, a second member connected to said tool means and including a second set of clutch teeth extending axially towards said rotary output shaft means; resilient means spacing said first and second sets of clutch teeth apart, said resilient means arranged to be overcome by operator pressure in applying said tool to a workpiece; said adjustable means comprising a stop member threadedly mounted on said housing for limiting the depth of engagement of said first and second sets of clutch teeth.

Claim 20

A power tool as claimed in claim 14 wherein each tooth in said first and second sets of clutch teeth comprises a driving face, said driving faces including a first surface region extending respectively from said first and said second members at a shallow angle to the axis of said clutch; and a second surface region extending from said first surface region at a larger angle from the axis of said clutch.

Claim 21

A power tool as claimed in claim 15 wherein each of said driving faces further includes a third surface region extending from said second surface region at a larger angle from the axis of said clutch.

Claim 22

A power tool as claimed in claim 14 wherein said tool means is slidably supported by said housing and wherein said adjustable means comprises a shoulder axially movably mounted on said housing for limiting the maximum possible movement of said tool means into said housing whereby the maximum torque transmission capacity of said clutch is adjustable.

Claim 23

A portable power tool as claimed in claim 14 wherein said output shaft is supported by a bearing fixed in said housing; said first member is axially limited by said bearing; said housing extends forwardly of and encloses first and second members and wheRein said adjustable means comprises an external collar movably mounted on said housing.

Claim 24

A power tool as claimed in claim 18 wherein said collar includes an internal extending surface positioned to limit the extent of movement of said tool means into said housing.

Claim 25

A power tool as claimed in claim 18 wherein said collar is mounted on said housing by means of said screw threads; and wherein a plurality of fixed positions are provided to which said collar can be positively located.

Claim 26

A portable power-operated tool of the type including a rotary output tool member and means for selecting the torque applied through said output member to a workpiece, said tool comprising a housing; motor means within said housing including rotary output shaft means; rotary tool means supported by said housing; torque transmitting clutch means within said housing for coupling said output shaft means with said tool means, said clutch means comprising complementary sets of clutch teeth respectively associated with said shaft means and said tool means; biasing means normally urging said clutch teeth to a spaced-apart position and adapted to be overcome upon engagement of said power tool with a workpiece; an adjustable means for limiting the maximum depth of engagement of said clutch teeth, said adjustable means comprising an adjusting collar threadedly mounted on said housing; stop means carried by said collar and cooperable with said tool means for limiting the movement of said tool means into said housing; locking collar means rotationally fixed to and axially slidable on said adjusting collar; said locking collar being juxtaposed with an exposed surface on said housing, said locking collar and said exposed surface including complementary engaging members for preventing rotation of said locking collar relative to said housing; and spring means normally urging said complementary engaging means into engagement.

Claim 27

A portable power-operated tool of the type including a rotary output tool member and means for selecting the torque applied through said output member to a workpiece, said tool comprising a housing; motor means within said housing including rotary output shaft means; rotary tool means supported by said housing; torque transmitting clutch means within said housing for coupling said output shaft means with said tool means, said clutch means comprising complementary sets of clutch teeth respectively associated with said shaft means and said tool means; biasing means normally urging said clutch teeth to a spaced-apart position and adapted to be overcome upon engagement of said power tool with a workpiece; an adjustable means for limiting the maximum depth of engagement of said clutch teeth, said adjustable means comprising an adjusting collar threadedly mounted on said housing; stop means carried by said collar and cooperable with said tool means for limiting the movement of said tool means into said housing; locking collar means rotationally fixed to and axially slidable on said adjusting collar; said locking collar being juxtaposed with an exposed surface on said housing, said locking collar and said exposed surface including complementary engaging members for preventing rotation of said locking collar relative to said housing; and spring means normally urging said complementary engaging means into engagement.

Claim 28

A portable power-operated tool as claimed in claim 21 wherein said locking collar includes axially extending pin means and wherein said surface on said housing includes axially opening aperture means for receiving said pins.

Claim 29

A portable power-operated tool as claimed in claim 21 wherein said locking collar comprises a plurality of ribs and wherein said adjusting collar comprises a plurality of grooves receiving said ribs whereby said locking collar and said adjusting collar are prevented from relative rotational movement.