Patent EP0131376A2 successfully refreshed from Google Patents.
EP0131376A2
Expired / Lapsed
EP
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Chop saw linkage system
Assignee: Black and Decker Inc
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Filing: 1984-06-06
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Granted: —
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Expires: 2004-06-06
Abstract
Abstract A chop saw (90) pivotably mounted for movement between a raised rest position and a lowered operational position, having a motor driven saw-blade (32) rotatably supported about a shaft (28), with a saw housing (106) partially encasing the saw-blade (32) and a swinging blade guard (108) which covers the exposed segment of the saw-blade (32) when the saw (90) is in the rest position. When the saw (90) is lowered to its operational position, a linkage system comprising four effective levers and four hinges clears the blade guard (108), thereby exposing the saw blade (32) to the work piece. To accommodate changing the saw blade (32) while the saw-unit (90) is in its rest position, the effective length of one of the levers can be temporarily reduced, thereby clearing the blade guard (108) from the exposed section of the saw blade (32). This provides easy access to the saw-blade (32) to be changed.
Inventors
- 👤 Horst Kaiser
- 👤 Rainer Herting
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 09:19
CPC Classifications
B; B27; B27G; B27G19/00; B27G19/02; B27G19/025
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
276 words
A chop saw (90) pivotally mounted on a bearing bracket (26) for movement between a lowered, operational position and a raised, rest position, having a motor driven saw blade (32) rotatably supported on a shaft (28), a housing (106) partially encasing the saw blade (32), and a swinging blade guard (108) disposed to cover an exposed segment of the saw blade (32) when the chop saw (90) is in the rest position, characterized in that a linkage system is provided for moving the blade guard (108) in response to movement of the chop saw (90) between the lowered and raised positions, such that the blade guard (108) immovably covers the exposed segment when the chop saw (90) is in the raised position and is moved to uncover the exposed segment when the chop saw (90) is moved to the lowered position, linkage system comprising a frame (105) fixed to and extending upwardly from the bearing bracket (26), a first hinge (101) for pivotally mounting the housing (106) near the base of the frame (105), a second hinge (102) pivotally attaching one end of an actuation lever (107) to the frame (105) upwardly from the first hinge (101), a third hinge (103) pivotally attaching the other end of the actuating lever (107) to the swinging blade guard (108)and a fourth hinge (104) pivotably connecting the swinging blade guard (108) to the housing (106), the third hinge (103), being eccentrically positioned on the blade guard (108) with respect to the fourth hinge (104) and the distance between the third (103) and fourth (104) hinges being substantially less than the distance between the first (101) and second (102) hinges.
Claim 2
Dependent Claim
276 words
A chop saw (90) pivotally mounted on a bearing bracket (26) for movement between a lowered, operational position and a raised, rest position, having a motor driven saw blade (32) rotatably supported on a shaft (28), a housing (106) partially encasing the saw blade (32), and a swinging blade guard (108) disposed to cover an exposed segment of the saw blade (32) when the chop saw (90) is in the rest position, characterized in that a linkage system is provided for moving the blade guard (108) in response to movement of the chop saw (90) between the lowered and raised positions, such that the blade guard (108) immovably covers the exposed segment when the chop saw (90) is in the raised position and is moved to uncover the exposed segment when the chop saw (90) is moved to the lowered position, linkage system comprising a frame (105) fixed to and extending upwardly from the bearing bracket (26), a first hinge (101) for pivotally mounting the housing (106) near the base of the frame (105), a second hinge (102) pivotally attaching one end of an actuation lever (107) to the frame (105) upwardly from the first hinge (101), a third hinge (103) pivotally attaching the other end of the actuating lever (107) to the swinging blade guard (108)and a fourth hinge (104) pivotably connecting the swinging blade guard (108) to the housing (106), the third hinge (103), being eccentrically positioned on the blade guard (108) with respect to the fourth hinge (104) and the distance between the third (103) and fourth (104) hinges being substantially less than the distance between the first (101) and second (102) hinges.
Claim 3
Dependent Claim
64 words
A chop saw linkage system according to claim 1, characterized in that means are provided for selectively disengaging the second hinge (102) to permit temporary shortening of the effective length of the actuation lever (107) and moving of the blade guard (108) to uncover the exposed segment when the chop saw (90) is in the raised position for facilitating changing the saw blade (32).
Claim 4
Dependent Claim
156 words
A chop saw linkage system according to claim 2, characterized in that the second hinge (102) is a pivot bolt having a shank received through a pivot point aperture (40) in the actuation lever (107) and a threaded end section threadably secured to the frame member (105), the threaded end section having a diameter less than the shank, the means for disengaging the second hinge (102) comprises an axial slot (41) in the actuation lever (107) adjoining the pivot point aperture (40), the width of the slot (41) being less than the diameter of the shank of the pivot bolt (102) and less than the diameter of the pivot point aperture (40) and greater than the diameter of the threaded portion, means being provided for partially withdrawing the threaded end section of the pivot bolt (102) from the frame (105) to dispose part of the threaded end section for slidable movement in the axial slot (41).
Claim 5
Dependent Claim
56 words
A chop saw linkage system according to claim 3, characterized in that the withdrawing means includes an opening (45) in the housing (106) providing access to the head of the pivot bolt (102) when the chop saw (90) is in the raised position permitting manual partial withdrawal of the threaded end section from the frame (105).
Claim 6
Dependent Claim
78 words
A chop saw linkage system according to claim 4, characterized in that the opening (45) includes a central bore (47) of insufficient diameter to permit removal of the pivot bolt (102) therethrough and an expanded inner cavity (49) of sufficient diameter to receive the head of the pivot bolt (102) and wherein disposition of the head of the pivot bolt (102) in the inner cavity (49) prevents the chop saw (90) from being moved to the lowered position.
Claim 7
Dependent Claim
53 words
A chop saw linkage system according to claim 3, characterized in that the actuation lever (107) is L-shaped and is connected to the pivot bolt (102) by its longer leg and is attached to the third hinge (103) by its shorter leg, permitting the linkage system to be essentially mounted in one plane.
Claim 8
Dependent Claim
33 words
A chop saw linkage system according to claim 6, characterized in that the axis of rotation of the fourth hinge (104) is the longitudinal axis of the shaft (104) supporting the saw-blade (32).
Claim 9
Dependent Claim
36 words
A chop saw linkage system according to claim 3, characterized in that a locking means (50, 52, 54, 55 and 56) detachably engages the actuation lever (107) when the saw (90) is in the. raised position.
References Cited (Backward Citations)
No citation records indexed.
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