← Back to Patent Explorer
US4431062A Expired / Lapsed US ⏱️ 0.0 years remaining

Rotating drive for impact hammer

Assignee: Robert Bosch GmbH
•
Filing: 1979-05-04
•
Granted: 1984-02-14
•
Expires: 1999-05-04
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A hand-held power tool with an electric drive motor, by means of which a rotary sleeve impacting upon a tool retainer holding a tool can be rotatably driven by a transmission, and by means of which an impacting mechanism can furthermore be driven. The power tool includes an axially oscillating drive piston, an impactor impinged by the drive piston over an air cushion which will transmit its impact energy onto the tool. A translation drive acts upon the drive piston with a rotatably driven drive member with a curved guide. At least one actuator follows the curve guide and acts upon the drive piston to effect its axial displacement. The drive member consists of a drive sleeve coaxial with and concentrically enclosing the drive piston and the impactor. The drive sleeve has a guide surface closed in itself in the circumferential direction and has an essentially steadily rising or falling incline with curve maxima and curve minima. The actuator is designed as a separate and freely movable rolling or sliding body and is in immediate contact with the drive piston at a location adjoining the guide surface. The rolling or sliding body is prevented from deviating along the guide surface by means of a positive retainer securing these like a cage, but held in the axial direction with a degree of freedom required for following this guide surface.

Inventors

  • 👤 Karl Wanner
  • 👤 Manfred Bleicher

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 09:39
CPC Classifications
B; B25; B25D; B25D17/00; B25D17/005; B25D11/00; B25D11/06; B25D11/08; B25D16/00; B25D17/06; B25D2211/00; B25D2211/003; B25D2211/06; B25D2211/062; B25D2211/064; B25D2250/00; B25D2250/191

Claims Analysis

Total Claims: 69
Claim 1
Independent Claim 280 words
Hand-held power tool, specifically an impact drill or hammer, with an electric drive motor, by means of which a rotary sleeve impacting upon a tool retainer holding a tool can be rotatably driven by a transmission, and by means of which an impacting mechanism can furthermore be driven, having an axially oscillating drive piston, an impactor impinged by the drive piston over an air cushion which will transmit its impact energy onto the tool, and having a translation drive acting upon the drive piston with a rotatably driven drive member, with a curved guide and at least one actuator following the curved guide and acting upon the drive piston to effect its axial displacement, characterized; (1) by the drive member consisting of a drive sleeve (28; 728) coaxial with and concentrically enclosing the drive piston (27; 721) and the impactor (23; 723), (2) by the drive sleeve (28; 728) having a guide surface (30; 780) closed in itself in the circumferential direction and having an essentially steadily rising or falling incline with curve maxima (32, 734) and curve minima (33; 733), (3) by the actuator being designed as a separate and freely movable at least one displacing body (31; 782; 783) and being in immediate contact with the drive piston (21 or 721) at a location adjoining the guide surface (30 or 780), and (4) by the displacing body (31; 782; 783) being prevented from deviating along the guide surface (30 or 630 or 780) by a positive retaining means (35-37; 665; 677; 784; 785) securing the displacing body like a cage, but being held in the axial direction with a degree of freedom required for following this guide surface.
Claim 2
Dependent Claim 280 words
Hand-held power tool, specifically an impact drill or hammer, with an electric drive motor, by means of which a rotary sleeve impacting upon a tool retainer holding a tool can be rotatably driven by a transmission, and by means of which an impacting mechanism can furthermore be driven, having an axially oscillating drive piston, an impactor impinged by the drive piston over an air cushion which will transmit its impact energy onto the tool, and having a translation drive acting upon the drive piston with a rotatably driven drive member, with a curved guide and at least one actuator following the curved guide and acting upon the drive piston to effect its axial displacement, characterized; (1) by the drive member consisting of a drive sleeve (28; 728) coaxial with and concentrically enclosing the drive piston (27; 721) and the impactor (23; 723), (2) by the drive sleeve (28; 728) having a guide surface (30; 780) closed in itself in the circumferential direction and having an essentially steadily rising or falling incline with curve maxima (32, 734) and curve minima (33; 733), (3) by the actuator being designed as a separate and freely movable at least one displacing body (31; 782; 783) and being in immediate contact with the drive piston (21 or 721) at a location adjoining the guide surface (30 or 780), and (4) by the displacing body (31; 782; 783) being prevented from deviating along the guide surface (30 or 630 or 780) by a positive retaining means (35-37; 665; 677; 784; 785) securing the displacing body like a cage, but being held in the axial direction with a degree of freedom required for following this guide surface.
Claim 3
Dependent Claim 19 words
Power tool as per claim 1, characterized by the displacing body (782; 783) being formed as a rolling body.
Claim 4
Dependent Claim 18 words
Power tool as per claim 1, characterized by the displacing body (31) being formed as a sliding body.
Claim 5
Dependent Claim 25 words
Machine as per claim 1, characterized by the guide surface (30 780) having in the axial direction a sinusoidal course applied onto the drive sleeve.
Claim 6
Dependent Claim 30 words
Power tool as per claim 1, characterized by the guide surface (30, 780) having in the axial direction an asymmetric course deviating from the sinusoidal, applied onto the drive sleeve.
Claim 7
Dependent Claim 70 words
Power tool as per claim 1, characterized by the number of alternating curve maxima (32; 732) and curve minima (33; 733) on the guide surface (30; 780) being so selected that for every revolution of one of the rotating drive sleeve (28; 728) and the positive retaining means (335; 435; 535), a plurality of blows will be imparted to the impactor (23; 723) and thus onto the tool (19, 719).
Claim 8
Dependent Claim 25 words
Power tool as per claim 1, characterized by a plurality of displacing bodies (31; 782; 783) being arranged in circumferential direction at equal angular distances.
Claim 9
Dependent Claim 18 words
Power tool as per claim 1, characterized by the displacing body (782; 783) being designed as a roller.
Claim 10
Dependent Claim 17 words
Power tool as per claim 1, characterized by the displacing body (31) being designed as a ball.
Claim 11
Dependent Claim 20 words
Power tool as per claim 1, characterized by the displacing body (31; 782; 783) being designed as a sliding piece.
Claim 12
Dependent Claim 23 words
Power tool as per claim 1, characterized by the displacing body (31; 782; 783) being designed as a body with a hollow interior.
Claim 13
Dependent Claim 36 words
Power tool as per claim 1, characterized by the positive retaining means (35; 135; 235; 335; 435; 535; 665, 667; 784, 785) being arranged in the housing non-rotatably relative to the drive sleeve (FIGS. 1-3, 9).
Claim 14
Dependent Claim 35 words
Power tool as per claim 1, characterized by the positive retaining means (35; 135; 235; 335; 435; 535; 665, 667; 784, 785) being arranged rotatably driven relative to the drive sleeve (FIGS. 4, 5, 8).
Claim 15
Dependent Claim 39 words
Power tool as per claim 1, characterized by the positive retaining means (35; 135; 235; 435; 535; 665, 667; 784, 785) being arranged non-rotatably, and by a clutch (667; 785-789) releasing the positive retaining means from its non-rotatable position.
Claim 16
Dependent Claim 34 words
Power tool as defined in claim 1, characterized by at least two of the drive sleeve (28), the rotary sleeve (20) and the tool holder (18) being jointly turnable and in joint coaxial arrangement.
Claim 17
Dependent Claim 34 words
Power tool as defined in claim 15, characterized by at least two of the drive sleeve (28), the rotary sleeve (20) and the tool holder (18) being integral with one another for joint turning.
Claim 18
Dependent Claim 33 words
Power tool as per claim 15, characterized by at least two of the drive sleeve (28), the rotary sleeve (20) and the tool holder (18) being connected with one another for joint rotation.
Claim 19
Dependent Claim 37 words
Power tool as per claim 1, characterized by at least two of the rotatably driven positive retaining means (335; 435; 535), the rotary sleeve (320; 420; 520) and the tool holder (318; 418; 578) being jointly turnable.
Claim 20
Dependent Claim 40 words
Power tool as per claim 18, characterized by at least two of the positive retaining means (335; 435; 535), the rotary sleeve (320; 420; 520) and the tool holder (318; 418; 518) being integral with one another for joint turning.
Claim 21
Dependent Claim 40 words
Power tool as per claim 18, characterized by at least two of the positive retaining means (335; 435; 535), the rotary sleeve (320; 420; 520) and the tool holder (318; 418; 518) being connected with one another for joint turning.
Claim 22
Dependent Claim 69 words
Power tool as per claim 1, characterized by the drive sleeve (26; 128; 228; 428; 628; 728) having on its end not facing the impactor, coaxial gear means (27; 127; 227; 627; 453; 791) rigidly coupled to the drive sleeve, and by the drive motor having on its motor shaft (26; 126; 326; 426) a drive pinion (25; 125; 325; 425) which is in mesh with the gear means.
Claim 23
Dependent Claim 26 words
Power tool as per claim 21, characterized by the gear means being formed by internal gearing (453; 791) provided on the end of the drive sleeve.
Claim 24
Dependent Claim 27 words
Power tool as per claim 21, characterized by the gear means being formed by an external gearing (453; 791) provided on the end of the drive sleeve.
Claim 25
Dependent Claim 25 words
Power tool as per claim 21, characterized by the gear means being formed as a gear (27; 127; 227; 627) coaxial with the drive sleeve.
Claim 26
Dependent Claim 20 words
Power tool as per claim 24, characterized by the coaxial gear being formed by a spur gear (127; 227; 627).
Claim 27
Dependent Claim 18 words
Power tool as per claim 24, characterized by the coaxial gear being formed by a bevel gear (27).
Claim 28
Dependent Claim 28 words
Power tool as per claim 21, characterized by the gear means being directly and rigidly coupled to the drive sleeve (FIGS. 1, 3 below; 5 below; 6, 9).
Claim 29
Dependent Claim 24 words
Power tool as per claim 21, characterized by a safety clutch (248, FIG. 3 top) which couples the gear means to the drive sleeve.
Claim 30
Dependent Claim 33 words
Power tool as per claim 1, characterized by the guide surface being arranged on an axial face (729) of the drive sleeve (728) and shaped as an axial cam surface (780, FIG. 9).
Claim 31
Dependent Claim 38 words
Power tool as per claim 29, characterized by the axial cam surface (780) being arranged on a radially projecting ring collar (781) on a portion of the circumference of the drive sleeve (728) not facing the impactor (723).
Claim 32
Dependent Claim 50 words
Power tool as per claim 29, characterized bu the impactor (723) as well as the drive piston (721) being arranged in succession within the drive sleeve (728) and the rotary sleeve (720) rigidly connected to it, and in such a manner that they may slide and will form a seal.
Claim 33
Dependent Claim 21 words
Power tool as per claim 31, characterized by the drive sleeve (728) and the rotary sleeve (720) being of integral construction.
Claim 34
Dependent Claim 74 words
Power tool as per claim 29, characterized by a positive retaining means consisting of at least one radial dowel (784) having at its end the displacing body (782; 783) that can rotate about the dowel axis and runs on the axial cam surface (780), and by the dowel (784) being held rigidly versus the housing (710), and allowing itself to be pressed with its displacing body (782; 783) against the axial cam surface (780).
Claim 35
Dependent Claim 27 words
Power tool as per claim 33, characterized by a compression spring (785) pressing the dowel (784) with its displacing body (782; 783) against the axial cam surface.
Claim 36
Dependent Claim 38 words
Power tool as per claim 33, characterized by the dowel (784) being designed as a piston pin (721) diametrally penetrating the drive piston (721) and held within it with the displacing bodies (782; 783) arranged at either end.
Claim 37
Dependent Claim 30 words
Power tool as per claim 34, characterized by the dowel and the drive piston (721) being in abutment against the housing (710) under the action of the compression spring (785).
Claim 38
Dependent Claim 20 words
Power tool as per claim 36, characterized by the dowel (784) and the drive pinion (721) being releasable for rotation.
Claim 39
Dependent Claim 64 words
Power tool as per claim 29, characterized by the drive sleeve (728) with its integral rotary sleeve (720) and integral tool holder (718) being supported on one side in the axial zone of the tool holder (718), and the ring collar (781) with its axial cam surface (780) being supported on the other within the housing (710), both respectively by a bearing (739; 778).
Claim 40
Dependent Claim 17 words
Power tool as per claim 38, characterized by the bearing being formed by an anti-friction bearing (739).
Claim 41
Dependent Claim 17 words
Power tool as per claim 38, characterized by the bearing being formed by a roller bearing (778).
Claim 42
Dependent Claim 26 words
Power tool as per claim 1, characterized by the guide surface (30) being arranged in the internal circumferential area of the drive sleeve (28, FIGS. 1-8).
Claim 43
Dependent Claim 44 words
Power tool as per claim 41, characterized by the guide surface being constructed as a guide groove (30) with an approximately semi-circular cross section of the groove, and by providing as an actuator a plurality of balls (31) in engagement with guide groove (301).
Claim 44
Dependent Claim 49 words
Power tool as per claim 41, characterized by the drive piston (21) being designed as a hollow piston with an axial piston (29) sleeve pointing towards the tool holder (18) and being open at that end within which the impactor (23) can be guided, sliding and forming a seal.
Claim 45
Dependent Claim 41 words
Power tool as per claim 41, characterized by the piston sleeve (29; 629) having on its outer circumferential area an actuating surface (34; 665, 666) engaged with at least one ball (31; 663, 664) as an actuator (FIGS. 1-5, 8, 6).
Claim 46
Dependent Claim 25 words
Power tool as per claim 44, characterized by the actuating surface (34; 665, 666) being an annular groove with which at least one ball engages.
Claim 47
Dependent Claim 57 words
Power tool as per claim 41, characterized by the positive retaining being formed by a guide sleeve (35) containing for every ball (31) at least one essentially axially running guide slot (36) within which the ball (31) is kept cage-like, being however movable in the direction of the extent of the guide slot (36, FIGS. 1-5, 8).
Claim 48
Dependent Claim 33 words
Power tool as per claim 46, characterized by the guide slot (36) provided for every ball (31) being inclined at an acute angle relative to an assumed axial line on the cylinder barrel.
Claim 49
Dependent Claim 33 words
Power tool as per claim 46, characterized by the guide slot (36) provided for every ball (31) and being of a curve-like shape relative to an assumed axial line of the cylinder barrel.
Claim 50
Dependent Claim 33 words
Power tool as per claim 46, characterized by the guide sleeve (35) running coaxial to the hollow piston (21), with piston sleeve (29), concentrically enclosing the latter and guiding it within its interior.
Claim 51
Dependent Claim 72 words
Power tool as per claim 46, characterized by the drive sleeve (28) enclosing the guide sleeve (35) at a radial distance and at least over that axial length over which at least one guide slot (36) extends, and by every ball (31) positively guided in a guide slot (36) radially protruding through the guide slot (36), engaging on one side the guide groove (30) and on the other the annular groove (34).
Claim 52
Dependent Claim 63 words
Power tool as per claim 46, characterized by the rotary sleeve (20; 120; 220; 620; 720) with the drive sleeve (28; 128; 228; 628; 778) and by the drive sleeve having a gear and being supported at its end facing away from the tool holder, in a manner allowing rotation and engaging of its gear with a drive pinion of the motor shaft.
Claim 53
Dependent Claim 31 words
Power tool as per claim 51, characterized by the drive sleeve being supported with its end facing away from the tool holder, on the guide sleeve (35; 135; 235; 435; 535).
Claim 54
Dependent Claim 28 words
Power tool as per claim 46, characterized by the guide sleeve (35; 135; 235) being held within the housing so that it is secured against turning (FIGS. 1-3).
Claim 55
Dependent Claim 66 words
Power tool as per claim 46, characterized by the rotary sleeve (320; 420; 520) being rigidly connected with the guide sleeve (335; 435; 535) and by the guide sleeve being supported in the housing so that it can rotate, the guide sleeve carrying a drive (327; 427) which is in mesh with a drive pinion (325; 425) of the motor shaft (326; 426, FIGS. 4, 5).
Claim 56
Dependent Claim 46 words
Power tool as per claim 54, characterized by the drive sleeve (328; 428) being rigidly connected by means of one of a shiftable friction or a positive clutch (350; 454-459), but so held in the housing that it can be released for rotation (FIGS. 4, 5).
Claim 57
Dependent Claim 69 words
Power tool as per claim 55, characterized by the drive sleeve (428) which is arranged rigidly by means of the clutch (454; 459) but free to rotate upon release of the clutch, being coupled to a transmission gear (453) which conjointly with the drive gear (427) of the driven guide sleeve (435) is in mesh with the drive pinion (425) of the motor shaft (426) but can be driven.
Claim 58
Dependent Claim 29 words
Power tool as per claim 56, characterized by the transmission gear (453) being driven in the direction opposite to the drive gear (427) of the driven guide sleeve (435).
Claim 59
Dependent Claim 29 words
Power tool as per claim 41, characterized by the rotary sleeve (20) being rigidly coupled to the tool holder (18) and supported in the coupling zone within the housing.
Claim 60
Dependent Claim 97 words
Power tool as per claim 41, characterized terized by the piston sleeve (629) having as an actuating surface on its external circumferential area, a radially recessed ball pocket (665; 666) for every ball (663; 664) with every ball within the pocket which acts as a positive retainer, being coupled, immovable axially and circumferentially, with the drive piston (621), and by the drive piston (621) being retained by a shiftable clutch (667) rigidly against the housing (610) or with the clutch released (667) being rotatable relative to the housing (610), conjointly with the drive sleeve (628, FIG. 6).
Claim 61
Dependent Claim 85 words
Power tool as per claim 59, characterized by the clutch (667) having a central ball cage (637) with clutch balls (674) held therein, ball groves (671) arranged on the drive piston (621), into which one respective clutch ball (674) will engage, and also having an external shifting ring (676) with holding pockets (677) for every clutch ball (674) arranged on its internal circumference and serving to hold the clutch balls (674) radially exiting from the ball grooves (675) when the clutch (FIG. 7) is released.
Claim 62
Dependent Claim 21 words
Power tool as per claim 60, characterized by the ball grooves being arranged on the drive piston parallel to its axis.
Claim 63
Dependent Claim 23 words
Power tool as per claim 60, characterized by the ball grooves being arranged on the drive piston in the shape of a helix.
Claim 64
Dependent Claim 30 words
Power tool as per claim 60, characterized by the central ball cage (673) of the clutch (667) being held rigidly within the housing (610) and supporting the drive piston (621).
Claim 65
Dependent Claim 28 words
Power tool as per claim 1, characterized by the motor shaft with the drive pinion being arranged parallel to the longitudinal axis of the drive pinion (FIGS. 2-5).
Claim 66
Dependent Claim 30 words
Power tool as per claim 1, characterized by the motor shaft with the drive pinion being arranged at an angle to the longitudinal axis of the drive piston (FIG. 1).
Claim 67
Dependent Claim 37 words
Power tool as per claim 1, characterized by the tool holder (18) having in its interior, at the side facing the impactor (23), a catching device (401) for the impactor (23) when in its expelled idling position.
Claim 68
Dependent Claim 42 words
Power tool as per claim 64, characterized by the catching device having within the tool holder (181) a clamping ring (401) and having on the impactor (23) a rin collar (41) with radially sloping shoulders (42; 43) arranged axially at both sides.
Claim 69
Dependent Claim 17 words
Power tool as per claim 67, characterized by the clamping ring (40) being formed by an O-ring.

References Cited (Backward Citations)

US1505493A Cited
DE1007148B Cited
US2492840A Cited
US2657383A Cited
US2974533A Cited
US2970483A Cited
SU612013A1 Cited
US3837410A Cited
US3924692A Cited
DE2449191A1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-02-13 1987-08-15 1988-02-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-02-13 1991-08-15 1992-02-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-02-13 1995-08-15 1996-02-14 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag