US3802222A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Torque-responsive clutch for hedge trimmers and the like
Assignee: Black and Decker Corp
•
Filing: 1972-08-30
•
Granted: 1974-04-09
•
Expires: 1992-08-30
Abstract
Abstract A hedge trimmer including an electric motor and a reciprocating cutter blade assembly in which a pinion driven by the motor engages a spur gear drivingly connected through a slip clutch to the reciprocating cutter assembly. The slip clutch includes telescoped driving and driven members defining an annular recess in which is disposed leaf spring means bent by engagement with both members to impose a torque-releasable driving connection therebetween.
Inventors
- 👤 E Weber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 23:01
CPC Classifications
F; F16; F16D; F16D7/00; F16D7/02; F16D7/021; A; A01; A01G; A01G3/00; A01G3/04; A01G3/047; A01G3/053
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
227 words
In a power-operated hedge trimmer including a housing; a motor in said housing; a transmission driven by said motor and including pinion gear means; a cutter blade assembly mounted on said housing; and slip-clutch means operatively connected between said pinion gear means and said cutter blade assembly; the improvement in which said slip-clutch means comprises: a spur gear driving member including means for journaling the same about an axis of rotation, said driving member including an annular recess opening into one side thereof concentric to the axis of rotation; an annular driven member journaled for rotation in said annular recess of said driving member, said driving member and driven member defining an annular recess between confronting inner and outer peripheries, said annular driven member including power take-off means operatively connected to said cutter blade assembly; and torquetransmitting, slip clutch means including spring means positioned in said recess between the respective confronting peripheries of said driving member and said driven member, said recess and said spring means being so dimensioned that said spring means is stressed at or above the yield point for its material when positioned in said recess, whereby to develop a constant predictable force between said driving and driven members, whereby torque over a predetermined value causes relative rotation between said driving member and drivEn member for protecting the operative components of the hedge trimmer.
Claim 2
Dependent Claim
227 words
In a power-operated hedge trimmer including a housing; a motor in said housing; a transmission driven by said motor and including pinion gear means; a cutter blade assembly mounted on said housing; and slip-clutch means operatively connected between said pinion gear means and said cutter blade assembly; the improvement in which said slip-clutch means comprises: a spur gear driving member including means for journaling the same about an axis of rotation, said driving member including an annular recess opening into one side thereof concentric to the axis of rotation; an annular driven member journaled for rotation in said annular recess of said driving member, said driving member and driven member defining an annular recess between confronting inner and outer peripheries, said annular driven member including power take-off means operatively connected to said cutter blade assembly; and torquetransmitting, slip clutch means including spring means positioned in said recess between the respective confronting peripheries of said driving member and said driven member, said recess and said spring means being so dimensioned that said spring means is stressed at or above the yield point for its material when positioned in said recess, whereby to develop a constant predictable force between said driving and driven members, whereby torque over a predetermined value causes relative rotation between said driving member and drivEn member for protecting the operative components of the hedge trimmer.
Claim 3
Dependent Claim
17 words
The structure as claimed in claim 1 in which said torque-transmitting, slip clutch means comprises leaf-spring means.
Claim 4
Dependent Claim
47 words
The structure as claimed in claimed 2 in which said leaf spring means comprises at least one elongated flat element disposed in distorted relationship in the annular recess between said confronting peripheries and extends edgewise generally along and spaced from the axis of rotation of said members.
Claim 5
Dependent Claim
37 words
The structure as claimed in claim 2 in which said leaf spring means comprises a plurality of independent leaf springs each bowed independently and having alternate portions engaged between respective peripheries of said driving and driven members.
Claim 6
Dependent Claim
37 words
The structure as claimed in claim 5 in which the driving member includes spaced axially extending notch portions disposed outwardly of the inner periphery thereof and each receiving terminal ends of an independent leaf spring element therein.
Claim 7
Dependent Claim
39 words
The structure as claimed in claim 1 in which said driving member includes an annular hub co-axial with and extending into said annular recess, said driven member having an annular recess complimentary to and journaled on said annular hub.
Claim 8
Dependent Claim
164 words
A torque-responsive slip-clutch for use in a hedge trimmer or the like between a pinion gear and a cutter assembly comprising a spur gear driving member having an annular recess opening axially from one side thereof, a driven member having power take-off means, said driven member being journaled within the annular recess of said driving member and defining therewith an axial recess between confronting annular surfaces, and resilient torque-transmitting slip clutch means interposed between and engaging the confronting surfaces of said driving and driven members, said axial recess and said resilient clutch means being so dimensioned that when said resilient clutch means is positioned in said axial recess in engagement with said member confronting surfaces, said resilient clutch means is stressed at or above the yield point for its material, whereby said clutch means exerts a known constant predictable force between said driving and driven members permitting relative rotation between the driving and driven members when torque between the members exceeds a predetermined value.
Claim 9
Dependent Claim
164 words
A torque-responsive slip-clutch for use in a hedge trimmer or the like between a pinion gear and a cutter assembly comprising a spur gear driving member having an annular recess opening axially from one side thereof, a driven member having power take-off means, said driven member being journaled within the annular recess of said driving member and defining therewith an axial recess between confronting annular surfaces, and resilient torque-transmitting slip clutch means interposed between and engaging the confronting surfaces of said driving and driven members, said axial recess and said resilient clutch means being so dimensioned that when said resilient clutch means is positioned in said axial recess in engagement with said member confronting surfaces, said resilient clutch means is stressed at or above the yield point for its material, whereby said clutch means exerts a known constant predictable force between said driving and driven members permitting relative rotation between the driving and driven members when torque between the members exceeds a predetermined value.
Claim 10
Dependent Claim
124 words
A torque-responsive slip-clutch construction comprising rotatable driving and driven members located adjacent one another, said driving and driven members having confronting, generally annular surfaces and defining an annular cavity, means holding said driving and driven member adjacent one another and preventing movement of said adjacent surfaces away from one another, spring means located in said cavity and engaging said surfaces of said driving and driven members, said cavity and said spring means being so dimensioned that when said spring means is positioned in said cavity and engaging said member surfaces, said spring means is stressed at or above the yield point for the material thereof, where by to develop a constant, predicatable frictional force normally causing conjoint rotation of said driving and driven members.
Claim 11
Dependent Claim
124 words
A torque-responsive slip-clutch construction comprising rotatable driving and driven members located adjacent one another, said driving and driven members having confronting, generally annular surfaces and defining an annular cavity, means holding said driving and driven member adjacent one another and preventing movement of said adjacent surfaces away from one another, spring means located in said cavity and engaging said surfaces of said driving and driven members, said cavity and said spring means being so dimensioned that when said spring means is positioned in said cavity and engaging said member surfaces, said spring means is stressed at or above the yield point for the material thereof, where by to develop a constant, predicatable frictional force normally causing conjoint rotation of said driving and driven members.
Claim 12
Dependent Claim
25 words
The structure as claimed in claim 8 in which said slip clutch means comprises distorted leaf spring means having engaging portions of the confronting surfaces.
Claim 13
Dependent Claim
35 words
The structure as claimed in claim 9 in which said leaf spring means comprises an elongated section distorted along its longitudinal axis with alternate portions of the distorted section in engagement with the confronting surfaces.
Claim 14
Dependent Claim
109 words
A torque-responsive slip-clutch comprising rotatable driving and driven members supported for rotation about a common axis, said members being telescoped and defining an annular recess formed by spaced, opposed annular surfaces, elongated spring means located in said cavity and stressed to engage said annular surfaces at spaced locations therearound, said cavity being dimensioned and said spring means being constructed of a Material and having a size and dimension such that when said spring means is interposed in said annular recess, said spring means is stressed at or above the yield point for the material thereof, whereby to develop a constant, predictable frictional force between said driving and driven members.
Claim 15
Dependent Claim
109 words
A torque-responsive slip-clutch comprising rotatable driving and driven members supported for rotation about a common axis, said members being telescoped and defining an annular recess formed by spaced, opposed annular surfaces, elongated spring means located in said cavity and stressed to engage said annular surfaces at spaced locations therearound, said cavity being dimensioned and said spring means being constructed of a Material and having a size and dimension such that when said spring means is interposed in said annular recess, said spring means is stressed at or above the yield point for the material thereof, whereby to develop a constant, predictable frictional force between said driving and driven members.
Claim 16
Dependent Claim
104 words
A power-operated device comprising a motor having a rotatable output shaft, a power train interconnected with said shaft and driven thereby, said power train including slip clutch means which comprises separable driving and driven members having spaced confronting surfaces defining recess means there-between, spring means located in said recess means to transmit torque from said driving to said driven member, said recess means being dimensioned and said spring means being constructed of a material and sized so that when said spring means is in position in said recess means, said spring means is stressed at or above the yield point for the material thereof.
Claim 17
Dependent Claim
104 words
A power-operated device comprising a motor having a rotatable output shaft, a power train interconnected with said shaft and driven thereby, said power train including slip clutch means which comprises separable driving and driven members having spaced confronting surfaces defining recess means there-between, spring means located in said recess means to transmit torque from said driving to said driven member, said recess means being dimensioned and said spring means being constructed of a material and sized so that when said spring means is in position in said recess means, said spring means is stressed at or above the yield point for the material thereof.
Claim 18
Dependent Claim
32 words
A device as defined in claim 12 wherein said spring means includes a plurality of elongated, relatively thin spring elements symmetrically disposed about the axis of rotation of said slip clutch members.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-04-08 | 1977-10-08 | 1978-04-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-08 | 1981-10-08 | 1982-04-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-08 | 1985-10-08 | 1986-04-09 | $7700.00 | Window Closed / Lapsed |