US3785443A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Portable electric impact tool
Assignee: Robert Bosch GmbH
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Filing: 1972-11-24
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Granted: 1974-01-15
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Expires: 1992-11-24
Abstract
Abstract A portable electric impact drill wherein an axially reciprocable tool spindle can be driven at two speeds by a gear transmission which is installed in front of a universal electric motor. The tool spindle is movable axially by a rotary or reciprocable selector to assume one of four positions including a first position in which it receives torque from a first gear of the transmission and is driven at a relatively low speed, a second position in which it receives torque from a second gear of the transmission and is driven at a relatively high speed, a third position in which it is disengaged from both gears, and a fourth position in which it receives torque from the second gear and causes an annulus of projections on the second gear to travel along an annulus of projections in the housing of the power tool so that the tool spindle rotates at the higher speed and is caused to perform axial oscillatory movements.
Inventors
- 👤 G Armbruster
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 03:49
CPC Classifications
B; B23; B23B; B23B45/00; B23B45/008; B25; B25D; B25D16/00; B25D16/006; B25F; B25F5/00; B25F5/001; B25D2211/00; B25D2211/06; B25D2211/062; B25D2211/064; Y; Y10; Y10T; Y10T74/00; Y10T74/19; Y10T74/19219; Y10T74/19293; Y10T74/19298; Y10T74/19307; Y10T74/19377; Y10T74/19414; Y10T74/19419; Y10T74/19442; Y10T74/19451; Y10T74/1946
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
172 words
In a portable power tool, particularly in a portable electric impact drill, a combination comprising a housing; a tool spindle rotatably and axially movably mounted in said housing; a multispeed transmission provided in said housing and including first and second gears rotatably mounted on said spindle and means for rotating said gears at different speeds, each of said gears having torque transmitting first coupling means and said spindle having torque receiving second coupling means; axial impulse transmitting means provided in said housing; and selector means actuatable to effect axial movements of said spindle between a plurality of positions including first and second positions in which said second coupling means respectively engages with and receives torque from the first coupling means of said first and second gears and a third position in which said second coupling means engages the first coupling means of one of said gears and at least said spindle receives axial impulses from said impulse transmitting means so that said spindle oscillates axially while being driven by said one gear.
Claim 2
Dependent Claim
172 words
In a portable power tool, particularly in a portable electric impact drill, a combination comprising a housing; a tool spindle rotatably and axially movably mounted in said housing; a multispeed transmission provided in said housing and including first and second gears rotatably mounted on said spindle and means for rotating said gears at different speeds, each of said gears having torque transmitting first coupling means and said spindle having torque receiving second coupling means; axial impulse transmitting means provided in said housing; and selector means actuatable to effect axial movements of said spindle between a plurality of positions including first and second positions in which said second coupling means respectively engages with and receives torque from the first coupling means of said first and second gears and a third position in which said second coupling means engages the first coupling means of one of said gears and at least said spindle receives axial impulses from said impulse transmitting means so that said spindle oscillates axially while being driven by said one gear.
Claim 3
Dependent Claim
60 words
A combination as defined in claim 1, wherein said one gear is movable with said tool spindle while the spindle moves axially from the respective one of said first and second axial positions to said third position, said impulse transmitting means being arranged to oscillate said spindle by way of said one gear in said third position of said spindle.
Claim 4
Dependent Claim
48 words
A combination as defined in claim 2, wherein said impulse transmitting means comprises a first annulus of projections provided in said housing and said one gear comprises a second annulus of projections which travel along the projections of said first annulus in said third position of said spindle.
Claim 5
Dependent Claim
34 words
A combination as defined in claim 1, further comprising electric motor means mounted in said housing and having a rotary output element arranged to drive said means for rotating said gears at different speeds.
Claim 6
Dependent Claim
23 words
A combination as defined in claim 1, further comprising means for biasing said tool spindle to at least one of said positions thereof.
Claim 7
Dependent Claim
68 words
A combination as defined in claim 1, wherein said tool spindle is provided with follower means at one end thereof and said selector means comprises a rotary element mounted in said housing and having a cam face tracked by said follower means, said rotary element being turnable by hand to thereby change the axial position of said spindle by way of said cam face and said follower means.
Claim 8
Dependent Claim
33 words
A combination as defined in claim 6, wherein said housing is provided with an opening and said rotary element has a roughened peripheral surface a portion of which extends outwardly through said opening.
Claim 9
Dependent Claim
53 words
A combination as defined in claim 6, wherein the configuration of said cam face is such that said follower means has freedom of limited axial movement relative to said rotary element in said third position of said spindle so that said spindle is free to oscillate while receiving torque from said one gear.
Claim 10
Dependent Claim
35 words
A combination as defined in claim 1, wherein said selector means is slidable relative to said housing between a plurality of positions each of which corresponds to a different axial position of said tool spindle.
Claim 11
Dependent Claim
49 words
A combination as defined in claim 1, wherein said housing includes an outer portion defining a chamber and a bridge member provided in said chamber, said spindle having a portion rotatable and axially movable in said bridge member and said impulse transmitting means being provided on said bridge member.
Claim 12
Dependent Claim
42 words
A combination as defined in claim 10, further comprising electric motor means installed in said chamber and having a rotary output element arranged to drive said means for rotating said gears at different speeds and being rotatably journaled in said bridge member.
Claim 13
Dependent Claim
41 words
A combination as defined in claim 11, wherein said means for rotating said gears at different speeds comprises an intermediate shaft mounted in said bridge member and a third gear mounted on said intermediate shaft and meshing with said first gear.
Claim 14
Dependent Claim
47 words
A combination as defined in claim 12, wherein said means for rotating said first and second gear at different speeds further comprises a second intermediate shaft mounted in said bridge member and a fourth gear mounted on said second intermediate shaft and meshing with said second gear.
Claim 15
Dependent Claim
30 words
A combination as defined in claim 13, wherein said selector means comprises a rotary element and a shaft for said rotary element, said shaft being mounted in said bridge member.
Claim 16
Dependent Claim
40 words
A combination as defined in claim 1, wherein said first and second gears are mirror symmetrical to each other with reference to a plane passing between said first and second gears and normal to the axis of said tool spindle.
Claim 17
Dependent Claim
45 words
A combination as defined in claim 1, wherein said housing comprises an outer portion defining a chamber for said transmission and a bridge member provided in said chamber and consisting of sintered metal, said spindle being rotatably and axially movably mounted in said bridge member.
Claim 18
Dependent Claim
21 words
A combination as defined in claim 1, wherein at least one of said first and second gears consists of sintered metal.
Claim 19
Dependent Claim
25 words
A combination as defined in claim 1, wherein said means for rotating said first and second gears comprises additional gear means consisting of sintered metal.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-01-14 | 1977-07-16 | 1978-01-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-14 | 1981-07-16 | 1982-01-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-14 | 1985-07-16 | 1986-01-15 | $7700.00 | Window Closed / Lapsed |