CA1113837A - Circular saw with riving knife - Google Patents
Circular saw with riving knifeInfo
- Publication number
- CA1113837A CA1113837A CA342,091A CA342091A CA1113837A CA 1113837 A CA1113837 A CA 1113837A CA 342091 A CA342091 A CA 342091A CA 1113837 A CA1113837 A CA 1113837A
- Authority
- CA
- Canada
- Prior art keywords
- riving knife
- circular saw
- saw according
- driven rocker
- bracket
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27G—ACCESSORY MACHINES OR APPARATUS FOR WORKING WOOD OR SIMILAR MATERIALS; TOOLS FOR WORKING WOOD OR SIMILAR MATERIALS; SAFETY DEVICES FOR WOOD WORKING MACHINES OR TOOLS
- B27G19/00—Safety guards or devices specially adapted for wood saws; Auxiliary devices facilitating proper operation of wood saws
- B27G19/08—Accessories for keeping open the saw kerf, e.g. riving knives or wedge plates
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Wood Science & Technology (AREA)
- Forests & Forestry (AREA)
- Sawing (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE:
A circular saw having a riving knife, a saw blade having an axis and adjustable in relation to a support surface of a baseplate, and a follow-up device to provide positive pivoting of the riving knife about the axis of the saw blade, character-ized in that the follow-up device has at least one additional degree of freedom permitting the riving knife to move in relation to its positive follow-up motion.
A circular saw having a riving knife, a saw blade having an axis and adjustable in relation to a support surface of a baseplate, and a follow-up device to provide positive pivoting of the riving knife about the axis of the saw blade, character-ized in that the follow-up device has at least one additional degree of freedom permitting the riving knife to move in relation to its positive follow-up motion.
Description
33~7 The present invention relates to a cixcular saw with a riving knife, and particularly to such a saw comprising a support plate and a saw~blade adjustable ln relation to the surface thereof, for the purpose of adjusting the ~epth of cut.
In the case of circular saws, it is known and prescribed that the ri~ing knife (or spLitting wedge) be arranged in such a manner that when the depth of cut is adjusted, the said knife does not alter its position in relation to the saw or to the highest point of the saw blade above the support surface. If the depth of cut is altered by displacing the saw housing and saw blade vertically in relation to the support plata, then, in known circular saws, the riving knife is secured to the motor-housing.
If, for the purpose of adjusting the depth of cut, the motor-housing and saw blade are connected pivotably to the support plate with a motor-carrier, then follow-up means must be provided, in known fashion, for the riving knife, to guide the latter as desired in relation to the saw blade.
Although the rivlngknife must normally be used to protect the operator, it is sometimes necessary to remove it for certain applications, for instance if the saw blade has to be introduced into the surface of the workpiece for the purpose of producing cut-outs in boards, or if, under certain circumstances, it is necessary to saw backwards. In such cases, the riving knife would interfere with the work and must therefore be removed. As soon as the circular saw is to be used again for normal work, the riving knife should be re-lnstalled, but this is often forgotten, or neglected for the sake of convenience, and the operator may thus be seriously endangered and injured by rebounding workpieces.
It is therefore the purpose of the invention to ,,".~ 1 : , , : '. ' : , . . ' . -:
~1383`7 arrange the riYing k~ife of a circu~ax s~ i~ such a m~p~er that the sa~ hlade may be inserted inta thle woxkpiece, ox the workpiece may be sawn baçkwards, without the necessity of removing the riving knife.
According to the present inYention there is provided a circular saw having a ri~ing knife, a saw blade having an axis and adjustable in relation to a support sur~ace of a base plate, and a follow-up device to provide positive pivot-ing of the riving knife about the axis of the saw blade, characterized in that the follow-up device has at least one additional degree of freedom permitting the riving knife to move in relation to its positive follow-up motion.
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Thus, when the saw blade is inserted into the workpiece, the riving knife is pivoted, preferably against the action of restoring force, behind the support surface and slides, during further sawing in the forward direction, in the cut produced by the sa~ blade. This ensures that the prescribed riving knife is in place during further sawing operations, and that the operator aannot therefore be endangered.
, According to one advantageous example of embodiment, this additional degree of freedom may be produced in that the length of the rocker which is not driven may be ~aried against a restoring force. Provision may also be made for one bearing of the articulated quadrangle to be made mobile.
A releasable locking device may be provided between the riving knife and the circular saw. In the locked position, - this device prevents free relative movement between the riving knlfe and the highest point on the saw blade. This eliminates the said additional degree of freedom, and the riving knife maintains its position at the highest point on ~. :
the saw blade. If a circular saw of this type is to be used
In the case of circular saws, it is known and prescribed that the ri~ing knife (or spLitting wedge) be arranged in such a manner that when the depth of cut is adjusted, the said knife does not alter its position in relation to the saw or to the highest point of the saw blade above the support surface. If the depth of cut is altered by displacing the saw housing and saw blade vertically in relation to the support plata, then, in known circular saws, the riving knife is secured to the motor-housing.
If, for the purpose of adjusting the depth of cut, the motor-housing and saw blade are connected pivotably to the support plate with a motor-carrier, then follow-up means must be provided, in known fashion, for the riving knife, to guide the latter as desired in relation to the saw blade.
Although the rivlngknife must normally be used to protect the operator, it is sometimes necessary to remove it for certain applications, for instance if the saw blade has to be introduced into the surface of the workpiece for the purpose of producing cut-outs in boards, or if, under certain circumstances, it is necessary to saw backwards. In such cases, the riving knife would interfere with the work and must therefore be removed. As soon as the circular saw is to be used again for normal work, the riving knife should be re-lnstalled, but this is often forgotten, or neglected for the sake of convenience, and the operator may thus be seriously endangered and injured by rebounding workpieces.
It is therefore the purpose of the invention to ,,".~ 1 : , , : '. ' : , . . ' . -:
~1383`7 arrange the riYing k~ife of a circu~ax s~ i~ such a m~p~er that the sa~ hlade may be inserted inta thle woxkpiece, ox the workpiece may be sawn baçkwards, without the necessity of removing the riving knife.
According to the present inYention there is provided a circular saw having a ri~ing knife, a saw blade having an axis and adjustable in relation to a support sur~ace of a base plate, and a follow-up device to provide positive pivot-ing of the riving knife about the axis of the saw blade, characterized in that the follow-up device has at least one additional degree of freedom permitting the riving knife to move in relation to its positive follow-up motion.
.
Thus, when the saw blade is inserted into the workpiece, the riving knife is pivoted, preferably against the action of restoring force, behind the support surface and slides, during further sawing in the forward direction, in the cut produced by the sa~ blade. This ensures that the prescribed riving knife is in place during further sawing operations, and that the operator aannot therefore be endangered.
, According to one advantageous example of embodiment, this additional degree of freedom may be produced in that the length of the rocker which is not driven may be ~aried against a restoring force. Provision may also be made for one bearing of the articulated quadrangle to be made mobile.
A releasable locking device may be provided between the riving knife and the circular saw. In the locked position, - this device prevents free relative movement between the riving knlfe and the highest point on the saw blade. This eliminates the said additional degree of freedom, and the riving knife maintains its position at the highest point on ~. :
the saw blade. If a circular saw of this type is to be used
2 -- . . . .
l~i;3 ~3~7 for insert-woxk, the locking deYice must be released, to allow the riYing knife to swing back behind the support plate.
- If, during further sawing, the said riving knife slides in the saw-cut, provision may be made for the locking device to engage automatically, in which case lt must be released again for the next insert-work. Provision may also be made to adjust the riving knife without any spring, weight, magnetic, hydraulic, or the like restoring force, but manual operation and locking in the terminal positions.
The riving knife according to the in~ention may be used with advantage both for portable circular saws and for stationary circular saws mounted on tables.
Examples of embodiment of the invention are described hereinafter in greater detail, without any limi~ative manner in conjunction with the drawings attached hereto, wherein:
Fig. 1 shows a portable circular saw, having a riving knife according to the invention, in part section;
Figs. 2-4 show diagrammatlc representatlons of ~0 three different examples of embodiment of the riving knife according to the invention with its follow-up device;
Fig. 5 is a section along the line V-V in Fig. 4;
Fig 6 is a section along the line VI-VI in Fig. 3;
Fig. 7 shows diagrammatically a table-mounted circular saw having a riving knife according to the invention and a follow-up device.
In the portable circular saw illustrated in Fig. 1, with vertical adjustment of the depth of cut, a motor-housing
l~i;3 ~3~7 for insert-woxk, the locking deYice must be released, to allow the riYing knife to swing back behind the support plate.
- If, during further sawing, the said riving knife slides in the saw-cut, provision may be made for the locking device to engage automatically, in which case lt must be released again for the next insert-work. Provision may also be made to adjust the riving knife without any spring, weight, magnetic, hydraulic, or the like restoring force, but manual operation and locking in the terminal positions.
The riving knife according to the in~ention may be used with advantage both for portable circular saws and for stationary circular saws mounted on tables.
Examples of embodiment of the invention are described hereinafter in greater detail, without any limi~ative manner in conjunction with the drawings attached hereto, wherein:
Fig. 1 shows a portable circular saw, having a riving knife according to the invention, in part section;
Figs. 2-4 show diagrammatlc representatlons of ~0 three different examples of embodiment of the riving knife according to the invention with its follow-up device;
Fig. 5 is a section along the line V-V in Fig. 4;
Fig 6 is a section along the line VI-VI in Fig. 3;
Fig. 7 shows diagrammatically a table-mounted circular saw having a riving knife according to the invention and a follow-up device.
In the portable circular saw illustrated in Fig. 1, with vertical adjustment of the depth of cut, a motor-housing
3 with a saw blade 4 is vertically displaceable in relation to a base-plate (or support-plate) 1 having a support surface 2. A riving knife (or splitting-wedge) carrier 5, to which . ~ .
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~13~3 7 :
~ .
a riving knife (spiittin~ wedge) 6 is secured detachably, is mounted pivotable upon motor-housing 3 aPd concentrically with axis 7 of saw blade 4. Motor-housing 3 also comprise a stop 8 and a tension-spring 9 between the said stop 8 and riving knlfe carrier 5, so that, in its posltlon of rest, the sald carrier bears against the said stop. At this time, riYing knife 6 assumes its position for normal sawing, with highest polnt 10 of saw blade 4 projectlng a few mlllimetres beyond the said riving knife.
If, for the purpose of sawing lnto the surface of the workpiece (insert-sawlng), the portable clrcular saw is now placed thereon wlth the blade rotating, then the saw blade penetrates into the workpiece, but riving knife 6 is swung back therefrom, against the action of tension spring 9, into the positlon shown in dotted lines ln Fig. 1, to allow the saw blade to enter into the workpiece untll support-surface 2 rests thereon. As the circular saw moves forward, riving knife 6 slides, under the action of tension spring 9, in the cut made by the saw blade, thus performing its prescribed safety function.
Figs. 2 to 4 are diagrammatic representations of portable circular saws having a pivotably mounted motor-carrier and a follow-up device for the rlving knife, various examples of the movement, according to the invention, of the riving knife being shown. Rocker 15 of a motor-houslng 16 is secured pivotally, in a bearing 13, 14, to a base (or support plate) 11 with a support surface 12, for the purpose of adjust-ing the depth of cut of saw blade 17. A riving knife carrier 19 is mounted pivotally upon motor-housing 16, and concentrical-30 ly with axis 18 of saw blade 17, a riving knife 20 being secured detachably to the said carrier 19. High-point 21 of saw blade 17 again projects by a specific amount beyong riving . , ~w - 4 -.~
~13~ 7 knife 20.
Riving knife carrier 19 is in the form of a~
elbow-lever, ri~ing knife 20 being secured to carrier-arm 22 thereof, while the other arm forms a link 23. Attached pivotally to hinge-point 24 of the said link is a rocker or connecting rod, or balance arm 25 (Fig. 2) or 26 (Flgs. 4 and 5), the other ends of the said rockers being connected at hinge-points 27, 28, 29 to support-plate 11.
The imaginary connecting lines between hinge-points 13-27, 14-28 and 13-29 form, in known fashion, in conjunction with driven rocker 15, link 23 and additional non driven rocker 25, 26 an articulated quadrangle which, when motor-housing 16 is plvoted, for the purpose of adjusting the depth of cut of saw blade 17, guides the riving knife 20 in such a manner as to keep the pre-determined distance between high-point 21 ..;
and the riving knife constant.
In order to achieve a further degree of freedom, rocker 25, as shown in Fig. 2, has a sleeve 30 attached pivotable to hinge-point 27. Mounted displaceably in the said sleeve ls a rod 31, and a compresslon sprlng 34 ls arranged between a plate 32 on rod 31 and end-wall 33 of the said sleeve. Rod 31 is connected pivotably to hinge-point 24 and, in the position of rest, plate 32 is urged by spring 34 towards the other end-wall 35 of sleeve 30.
The arrangement according to the invention, illustrated in Fig. 2, provides guidance (follow-up) for riving knife 20 upon adjustment of the depth of cut. If the circular saw is used for insert-sawing, riving knlfe 20 is ; swung away from the surface of the workpiece, against the action of compression spring 34, into the position shown in dotted lines in Fig. 2. After a saw-cut has been made, compression spring 34 automatically guides the said riving ~ ~ ~ 5 , , ~ .
. . . .
~13~3 ~
knife in the said cut~
In Fig. 3, hiP~e-point 28 is not.attached.to support-plate 11, but is connected pi~ota.lly, by ~eans of an intermediate member 36, to bearing 14 secured to support-plate 11. A compression spring 37 is arranged between in.ter~ediate member 36 and bracket 38 on.support-plate ll, the said sprin.g urging the said intermediate member towards a stop-cam 39 on bracket 38. Again in this example of embodiment, rivin.g knife 20 may be pivoted, during insert-sawing, towards support-surface 12. After a saw-cut has been made~it returns auto-matically to its position of rest.
As shown in Figs. 4 and 5, in these examples of ~.
embodiment hinge-point 29 is mounted in a curved slot 40 ~:~
. in a bracket 41 on support-plate 11. A shoulder-bolt 43 is located in a hole 42 in rocker 26, the said bolt being ~.
displaceable in slot 40 and being adapted to be locked to . bracket 41 by means of a wing-nut 44. In this example of embodiment, the additional degree of freedom may be eliminated ~ by the operator, the mo~ement of the riving kn.i~e being 20 limited to the follow-up movement. When wing-nut 44 is loosened, .; the displaceable arrangement of hinge-point 29 in slot 40 .
allows riving knife 20 to be swung towards support-surface 12 when saw blade 17 is used for insert-sawing.
Fig. 6 shows a modification of the design according ;
to Fig. 3. In this case, bearing 14 is in the form of a double hinge-point, carrying both rocker 15 for motor-housing .
~: 16 and intermediate member 36. :
Intermediate member 36 is mounted upon a bearing ; bolt 45 whlch is rotatable in bracket 38. An adjusting wheel 47 is secured to the said bolt by means of a pin 46. Arranged between adjusting wheel 47 and bracket 38 is a helical spring 48 which holds the said i~termediate ~ember, through bolt 45, .
. ~ 6 ~,-''~ ' .
, . ~ . . , ., ,: . - . :
~131~3 7 in the position of rest shown i~ Fig. 3.
A lock-pin 50 is mounted displaceably in a hole 49 in adjusting wheel 47, the said pin ha~ing t~o grooves 51 in which a spring-loaded ball 52 engages. When lock-pin 50 is in the release position, adjusting wheel 47 may ~otate freely, but when the said pin engages in a hole 53 in ~racket 38, the said wheel is locked thereto. In this case, the additional degree of freedom of ri~ing knife 20 is again ` eliminated.
The use of the riving knife according to the 5' invention in a stationary, table-mounted circular saw is shown in Fig. 7. Here again rocker 57 of motor-housing 58, with its saw blade 59, is mounted pivotably on a bracket 54 on support-table 55. Riving knife 60 is secured detachably ~; to one arm of riving knife carrier 61, the other arm thereof , .
forming link 62 of an articulated quadrangle which is complemented by a rocker 63 corresponding to rocker 25 in ` Fig. 3. One end of rocker 63 is secured to hinge-point 64 on bracket 54, while the other end is secured to hinge-point 65 on link 62.
Stationary, table-mounted circular saws are usually provided with a protective hood which may be secured pivotally to the end of riving knife 60, but this hood must be removed if the riving knife is to be used in accordance with the invention. When a workpiece 66 is in position, riving knife 60 assumes the position shown in full lines in Fig. 7. When the workpiece is removed, it returns to the position of rest ,. . .
shown in dotted lines.
, .' .
, ~ ' ., ' ' ~ ' ' , "
,;'.,.. ' .
.
~13~3 7 :
~ .
a riving knife (spiittin~ wedge) 6 is secured detachably, is mounted pivotable upon motor-housing 3 aPd concentrically with axis 7 of saw blade 4. Motor-housing 3 also comprise a stop 8 and a tension-spring 9 between the said stop 8 and riving knlfe carrier 5, so that, in its posltlon of rest, the sald carrier bears against the said stop. At this time, riYing knife 6 assumes its position for normal sawing, with highest polnt 10 of saw blade 4 projectlng a few mlllimetres beyond the said riving knife.
If, for the purpose of sawing lnto the surface of the workpiece (insert-sawlng), the portable clrcular saw is now placed thereon wlth the blade rotating, then the saw blade penetrates into the workpiece, but riving knife 6 is swung back therefrom, against the action of tension spring 9, into the positlon shown in dotted lines ln Fig. 1, to allow the saw blade to enter into the workpiece untll support-surface 2 rests thereon. As the circular saw moves forward, riving knife 6 slides, under the action of tension spring 9, in the cut made by the saw blade, thus performing its prescribed safety function.
Figs. 2 to 4 are diagrammatic representations of portable circular saws having a pivotably mounted motor-carrier and a follow-up device for the rlving knife, various examples of the movement, according to the invention, of the riving knife being shown. Rocker 15 of a motor-houslng 16 is secured pivotally, in a bearing 13, 14, to a base (or support plate) 11 with a support surface 12, for the purpose of adjust-ing the depth of cut of saw blade 17. A riving knife carrier 19 is mounted pivotally upon motor-housing 16, and concentrical-30 ly with axis 18 of saw blade 17, a riving knife 20 being secured detachably to the said carrier 19. High-point 21 of saw blade 17 again projects by a specific amount beyong riving . , ~w - 4 -.~
~13~ 7 knife 20.
Riving knife carrier 19 is in the form of a~
elbow-lever, ri~ing knife 20 being secured to carrier-arm 22 thereof, while the other arm forms a link 23. Attached pivotally to hinge-point 24 of the said link is a rocker or connecting rod, or balance arm 25 (Fig. 2) or 26 (Flgs. 4 and 5), the other ends of the said rockers being connected at hinge-points 27, 28, 29 to support-plate 11.
The imaginary connecting lines between hinge-points 13-27, 14-28 and 13-29 form, in known fashion, in conjunction with driven rocker 15, link 23 and additional non driven rocker 25, 26 an articulated quadrangle which, when motor-housing 16 is plvoted, for the purpose of adjusting the depth of cut of saw blade 17, guides the riving knife 20 in such a manner as to keep the pre-determined distance between high-point 21 ..;
and the riving knife constant.
In order to achieve a further degree of freedom, rocker 25, as shown in Fig. 2, has a sleeve 30 attached pivotable to hinge-point 27. Mounted displaceably in the said sleeve ls a rod 31, and a compresslon sprlng 34 ls arranged between a plate 32 on rod 31 and end-wall 33 of the said sleeve. Rod 31 is connected pivotably to hinge-point 24 and, in the position of rest, plate 32 is urged by spring 34 towards the other end-wall 35 of sleeve 30.
The arrangement according to the invention, illustrated in Fig. 2, provides guidance (follow-up) for riving knife 20 upon adjustment of the depth of cut. If the circular saw is used for insert-sawing, riving knlfe 20 is ; swung away from the surface of the workpiece, against the action of compression spring 34, into the position shown in dotted lines in Fig. 2. After a saw-cut has been made, compression spring 34 automatically guides the said riving ~ ~ ~ 5 , , ~ .
. . . .
~13~3 ~
knife in the said cut~
In Fig. 3, hiP~e-point 28 is not.attached.to support-plate 11, but is connected pi~ota.lly, by ~eans of an intermediate member 36, to bearing 14 secured to support-plate 11. A compression spring 37 is arranged between in.ter~ediate member 36 and bracket 38 on.support-plate ll, the said sprin.g urging the said intermediate member towards a stop-cam 39 on bracket 38. Again in this example of embodiment, rivin.g knife 20 may be pivoted, during insert-sawing, towards support-surface 12. After a saw-cut has been made~it returns auto-matically to its position of rest.
As shown in Figs. 4 and 5, in these examples of ~.
embodiment hinge-point 29 is mounted in a curved slot 40 ~:~
. in a bracket 41 on support-plate 11. A shoulder-bolt 43 is located in a hole 42 in rocker 26, the said bolt being ~.
displaceable in slot 40 and being adapted to be locked to . bracket 41 by means of a wing-nut 44. In this example of embodiment, the additional degree of freedom may be eliminated ~ by the operator, the mo~ement of the riving kn.i~e being 20 limited to the follow-up movement. When wing-nut 44 is loosened, .; the displaceable arrangement of hinge-point 29 in slot 40 .
allows riving knife 20 to be swung towards support-surface 12 when saw blade 17 is used for insert-sawing.
Fig. 6 shows a modification of the design according ;
to Fig. 3. In this case, bearing 14 is in the form of a double hinge-point, carrying both rocker 15 for motor-housing .
~: 16 and intermediate member 36. :
Intermediate member 36 is mounted upon a bearing ; bolt 45 whlch is rotatable in bracket 38. An adjusting wheel 47 is secured to the said bolt by means of a pin 46. Arranged between adjusting wheel 47 and bracket 38 is a helical spring 48 which holds the said i~termediate ~ember, through bolt 45, .
. ~ 6 ~,-''~ ' .
, . ~ . . , ., ,: . - . :
~131~3 7 in the position of rest shown i~ Fig. 3.
A lock-pin 50 is mounted displaceably in a hole 49 in adjusting wheel 47, the said pin ha~ing t~o grooves 51 in which a spring-loaded ball 52 engages. When lock-pin 50 is in the release position, adjusting wheel 47 may ~otate freely, but when the said pin engages in a hole 53 in ~racket 38, the said wheel is locked thereto. In this case, the additional degree of freedom of ri~ing knife 20 is again ` eliminated.
The use of the riving knife according to the 5' invention in a stationary, table-mounted circular saw is shown in Fig. 7. Here again rocker 57 of motor-housing 58, with its saw blade 59, is mounted pivotably on a bracket 54 on support-table 55. Riving knife 60 is secured detachably ~; to one arm of riving knife carrier 61, the other arm thereof , .
forming link 62 of an articulated quadrangle which is complemented by a rocker 63 corresponding to rocker 25 in ` Fig. 3. One end of rocker 63 is secured to hinge-point 64 on bracket 54, while the other end is secured to hinge-point 65 on link 62.
Stationary, table-mounted circular saws are usually provided with a protective hood which may be secured pivotally to the end of riving knife 60, but this hood must be removed if the riving knife is to be used in accordance with the invention. When a workpiece 66 is in position, riving knife 60 assumes the position shown in full lines in Fig. 7. When the workpiece is removed, it returns to the position of rest ,. . .
shown in dotted lines.
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, ~ ' ., ' ' ~ ' ' , "
,;'.,.. ' .
Claims (19)
1. A circular saw having a riving knife, a saw blade having an axis and adjustable in relation to a support surface of a base-plate, and a follow-up device to provide positive pivoting of the riving knife about the axis of the saw blade, characterized in that the follow-up device has at least one additional degree of freedom permitting the riving knife to move in relation to its positive follow-up motion.
2. A circular saw according to claim 1, character-ized in that the follow-up device comprises a mobile bearing element cooperating with said riving knife.
3. A circular saw according to claim 2, wherein said follow-up device is in the form of an articulated quadrangle having links formed by one arm of a carrier for carrying said riving knife, a driven rocker thereof and a motor-carrier, characterized in that said one arm moves independently of said driven rocker.
4. A circular saw according to claim 3, character-ized in that said articulated quadrangle is further provided with a non-driven rocker which is adjustable against a restoring force.
5. A circular saw according to claim 4, character-ized in that it further comprises a releasable locking element which in a locking position prevents relative movement between the riving knife and a high point on said saw blade.
6. A circular saw according to claim 2, wherein said riving knife is pivotally and concentrically mounted about the axis of said saw blade by means of a riving knife carrier.
7. A circular saw according to claim 6, wherein said riving knife is detachably secured to one end of said riving knife carrier, the other end of said riving knife carrier being pivotally and concentrically mounted about said axis of said saw blade.
8. A circular saw according to claim 7, wherein said riving knife carrier is in the form of an elbow-lever having a carrier arm which carries said riving knife at its one end and having another arm in the form of a link.
9. A circular saw according to claim 8, wherein said link is provided with an hinge point to which is connected one end of a non-driven rocker, the other end of said non-driven rocker being connected by means of a hinge point system to said base plate.
10. A circular saw according to claim 9, wherein a driven rocker of a motor housing is secured pivotally by bearing means to said base plate for adjusting the depth of cut of said saw blade.
11. A circular saw according to claim 10, wherein an imaginary connecting line between said bearing means and said hinge point system, in conjunction with said driven rocker, said link and said non-driven rocker form an articulated quadrangle which, when said motor housing is pivoted guides said riving knife in such a manner as to keep a predetermined distance between said riving knife and a high point on said saw blade constant.
12. A circular saw according to claim 9, wherein said non driven rocker is provided with a sleeve connected pivotally to said hinge point system, a rod being displaceably mounted in said sleeve and a compression spring being arranged between a plate on said rod and an end wall of said sleeve, in the position of rest, said plate being urged by said spring towards said end wall of said sleeve.
13. A circular saw according to claim 9, wherein said hinge point system is pivotally connected by means of an intermediate member to a bearing means secured to said base plate by means of bracket, a compression spring being arranged between said intermediate member and said bracket, said spring urging said intermediate member torwards a stop cam on said bracket.
14. A circular saw according to claim 9, wherein said hinge point system is mounted in a curved slot provided in a bracket connected to said base plate, a shoulder bolt being located in a hole in said non driven rocker, said bolt being displaceable in said slot and being adapted to be locked to said bracket by means of a wing nut.
15. A circular saw according to claim 13, wherein said bearing means is in the form of a double hinge point, carrying both said driven rocker and said intermediate member.
16. A circular saw according to claim 15, wherein said intermediate member is mounted upon a bearing bolt which is rotatable in said bracket, an adjusting wheel being secured to said bearing bolt by means of a pin, a helical spring being arranged between said adjusting wheel and said bracket which holds said intermediate member through said bolt in a position of rest.
17. A circular saw according to claim 16, wherein a lock pin is displaceably mounted in a hole in said adjusting wheel, said lock pin having two grooves in which a spring loaded ball engages.
18. A circular saw according to claim 9, wherein said driven rocker of said motor housing with its saw blade is pivotably mounted on a bracket of a support table, the riving knife being detachably secured to one arm of said riving knife carrier, the other end of said riving knife carrier forming a link of said articulated quadrangle, one end of said non driven rocker being secured to a hinge point on said bracket, while the other end is secured to a hinge point of said link.
19. A circular saw according to claim 18, further comprising a protective hood pivotally secured to one end of said riving knife.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEP2854369.3 | 1978-12-16 | ||
| DE2854369A DE2854369C2 (en) | 1978-12-16 | 1978-12-16 | Circular saw with riving knife |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1113837A true CA1113837A (en) | 1981-12-08 |
Family
ID=6057363
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA342,091A Expired CA1113837A (en) | 1978-12-16 | 1979-12-14 | Circular saw with riving knife |
Country Status (5)
| Country | Link |
|---|---|
| EP (1) | EP0012404B1 (en) |
| AT (1) | ATE3382T1 (en) |
| CA (1) | CA1113837A (en) |
| DE (1) | DE2854369C2 (en) |
| ES (1) | ES486928A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5481806A (en) * | 1994-06-27 | 1996-01-09 | Pratt; Edgar L. | Tongue attachment for circular saw |
Families Citing this family (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3206419A1 (en) * | 1982-02-23 | 1983-09-01 | Eugen Lutz GmbH u. Co Maschinenfabrik, 7130 Mühlacker | Saw unit |
| DE3912307A1 (en) * | 1989-04-14 | 1990-10-25 | Metabowerke Kg | Splitting knife support mechanism for circular saw - has simple spring-loaded cam system for optimum positioning of knife |
| DE3933261A1 (en) * | 1989-10-05 | 1991-04-18 | Bosch Gmbh Robert | Circular saw |
| DE4010456A1 (en) * | 1990-03-31 | 1991-10-02 | Elektra Beckum Lubitz & Co | Combined cut=off and table type circular saw - has telescopic strut to lock vertical traverse of saw unit when inverted in table saw mode |
| GB2273078A (en) * | 1992-12-04 | 1994-06-08 | Black & Decker Inc | Adjustable riving knife |
| US5381233A (en) * | 1993-03-03 | 1995-01-10 | National Tsing Hua University | Polarized-light scatterometer for measuring the thickness of a film coated on the partial of a substrate |
| DE19635527A1 (en) * | 1996-08-20 | 1998-02-26 | Black & Decker Inc | Hand-held circular saw |
| US7437981B2 (en) | 2005-11-21 | 2008-10-21 | Robert Bosch Gmbh | Modular guard system and apparatus for a power saw |
| US7600456B2 (en) | 2005-11-21 | 2009-10-13 | Robert Bosch Gmbh | Modular guard system for a power saw |
| DE102007062256A1 (en) | 2007-12-21 | 2009-06-25 | Robert Bosch Gmbh | circular saw |
| US8127648B2 (en) | 2008-07-31 | 2012-03-06 | Robert Bosch Gmbh | Table saw guard system |
| DE102012005173A1 (en) * | 2012-03-16 | 2013-09-19 | Festool Group Gmbh & Co. Kg | Hand-cutting machine |
| DE102012005169A1 (en) * | 2012-03-16 | 2013-09-19 | Festool Group Gmbh & Co. Kg | Hand-cutting machine |
| DE102012005165A1 (en) * | 2012-03-16 | 2013-09-19 | Festool Group Gmbh & Co. Kg | Hand-cutting machine |
| DE102013101480A1 (en) | 2013-02-14 | 2014-08-14 | Wolfcraft Gmbh | Saw table top with splitting wedge attachable to it |
| DE102016103152A1 (en) * | 2016-02-23 | 2017-08-24 | Eberhard Berhalter | Machine tool device |
| DE102017201493A1 (en) * | 2017-01-31 | 2018-08-02 | Robert Bosch Gmbh | Circular saw, in particular circular saw |
| DE102019119230A1 (en) | 2019-07-16 | 2021-01-21 | Homag Gmbh | Unit for grooving and separating cut machining with chip guiding function |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1435252A (en) * | 1919-12-17 | 1922-11-14 | John C Haswell | Separating device for sawing machines |
| US1602040A (en) * | 1925-03-05 | 1926-10-05 | Stover Lumber Company | Separating device for resawing machines |
| US1711490A (en) * | 1927-09-12 | 1929-05-07 | William D Drummond | Saw guard |
| US2530867A (en) * | 1949-03-28 | 1950-11-21 | Galanga Charles | Spreaders for circular saw wood cutting machines |
| US2518684A (en) * | 1949-04-21 | 1950-08-15 | Hyman M Harris | Duplex bench saw |
| DE1202964B (en) * | 1957-12-19 | 1965-10-14 | Reich Maschf Gmbh Karl | Circular saw with riving knife |
| US2916062A (en) * | 1958-09-18 | 1959-12-08 | Dormeyer Corp | Splitter for portable electric saw |
| CH393716A (en) * | 1959-07-24 | 1965-06-15 | Metabowerke Kg | Circular saw with a riving knife downstream of the saw blade |
| FR2087454A5 (en) * | 1970-05-20 | 1971-12-31 | Guilliet Ets |
-
1978
- 1978-12-16 DE DE2854369A patent/DE2854369C2/en not_active Expired
-
1979
- 1979-12-10 EP EP79105023A patent/EP0012404B1/en not_active Expired
- 1979-12-10 AT AT79105023T patent/ATE3382T1/en active
- 1979-12-14 ES ES486928A patent/ES486928A1/en not_active Expired
- 1979-12-14 CA CA342,091A patent/CA1113837A/en not_active Expired
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5481806A (en) * | 1994-06-27 | 1996-01-09 | Pratt; Edgar L. | Tongue attachment for circular saw |
Also Published As
| Publication number | Publication date |
|---|---|
| DE2854369C2 (en) | 1983-10-20 |
| EP0012404B1 (en) | 1983-05-18 |
| ES486928A1 (en) | 1980-05-16 |
| DE2854369A1 (en) | 1980-06-19 |
| ATE3382T1 (en) | 1983-06-15 |
| EP0012404A1 (en) | 1980-06-25 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |