An embodiment of the present invention will now be described with reference to the accompanying drawings of which:
The embodiment of the invention described herein relates to a sliding compound miter saw, similar to that described in WO98/18588, which has a table mounted on top of the motor unit to enable the saw to act as a table saw.
Referring to
A bevel mount 110 is connected to the rear of the rotatable table 104. Bevel mount 110 is able to pivot about a horizontal axis in relation to the rotatable table 104. The pivotal movement of the bevel mount 110 in relation to the rotatable table 14 enables the sliding compound miter saw to perform bevel cuts.
Two guide rods 112, 116 as slideably mounted onto the bevel mount 110. The rods 112,116 are capable of sliding horizontally, backwards and forwards. The rods 112, 116 enable the sliding compound miter saw to perform sliding cuts.
A motor unit 118 is pivotally mounted on a motor support 208 which is rigidly attached to the ends of the guide rods 112, 116. A motor unit 118 comprises a motor (not shown) for rotationally driving a circular saw blade 120 mounted on a drive spindle on the motor unit 118. The pivotal movement of the motor unit 118 in relation to the guide rods 112, 116 enable the saw to perform chop cuts. The motor unit 118 is biased to an upward position by a spring (not shown). A slot 122 extends across the rotatable table 104 and along the extension arm 106.
A table 114 mounted on the top of the saw enables the sliding compound miter saw to be also used as a table saw. The table 114 is attached to the top side of the motor unit 118. A slot 124 is formed through the table 114 through which the top section of the circular saw blade 120 projects. The motor unit 118 can be locked in a downward position such that the table 114 is horizontal. A workpiece such as a piece of wood can then be slid across the top of the table 114 to engage with the top section of the saw blade 120 thus enabling the sliding compound miter saw to be used as a table saw. A riving knife 126 is located towards the rear of the saw blade 120 and a guard 128 can surround the top of the saw blade 120 when the saw is not being used as a table saw, which includes a chute 130 for the extraction of wood chips.
The saw comprises a plurality of guards located below the table 114 which are capable of enclosing the lower section of the saw blade 120 when the saw is not being used as a sliding compound miter saw for performing chop, miter, bevel or sliding cuts, for example when the saw is being used as a table saw, with the motor unit 118 locked downwardly.
Referring to FIGS. 1 and 3-6, a handle 132 is attached to the motor unit 118 by which a user can grip and pivot the motor unit 118 and the circular saw blade 120 downwards towards the rotatable table 104. An electric switch 134 is mounted on the handle 132 for activating the motor.
The motor unit 118 can be locked using a motor unit pivot locking mechanism in its lowest pivotal position (
The motor unit pivot locking mechanism comprises a slideable locking rod 500 which is capable of being slid along its longitudinal axis 510 with a tubular aperture 502 formed through a part 504 of the motor support 208. One end (not shown) of the tubular aperture 502 faces a side wall 506 of the motor unit 118.
A recess (not shown) is formed within the wall 506 which is capable of receiving the non-visible end of the slideable locking rod 500 when it is aligned with the non-visible end of the tubular aperture 502. The recess is located within the wall 506 of the motor unit in a position so that it is aligned with the non-visible end of the tubular aperture 502 when the motor unit 118 is located in its lowest position. When the motor unit 118 is in its lowest position, the non-visible end of the locking rod 500 is slid into the recess. The motor unit 118 is then locked in its lowest position against the biasing force of the spring and prevented from pivoting. In order to release the motor unit 118, the locking rod 500 is slid along its longitudinal axis, withdrawing the end of which from the recess, allowing the motor unit 118 to be pivoted. When the motor unit 118 is in any other position other than its lowest, the recess is not aligned with the tubular aperture 502 and therefore, the end of the locking rod 500 cannot be slid into it. Thus the locking mechanism cannot be operated. When the locking rod 500 is in the unlocked position so that the motor unit 118 can pivot, the exposed end 508 extends further away from the motor support 208 than when it is in the locked position. The exposed end 508 of the locking rod 500 comprises a finger grip region. A retention mechanism (not shown) prevents the locking rod 500 from being withdrawn completely from the motor support 208.
When the motor unit 118 is in the locked lower position, the table 114 is horizontal. In this position the table 114 can be used as a table saw, the workpiece 216 being cut by the part of the saw blade 120 which passes through the slot 124. The height of the table 114, and hence the amount of saw blade 120 passing through it, can be adjusted vertically. This is described in more detail further below.
The lower part of the circular saw blade 120 below the table 114 is surrounded by a guard actuation assembly. The guard actuation assembly which will now be described in more detail.
A first fixed guard 218 surrounding top and middle sections of the circular saw blade 120 is attached to the motor unit 118. A “fixed guard”, such as the first fixed guard 218, is a blade guard which remains stationary relative to the motor unit 118.
A second forward pivotal guard 220 is pivotally attached to the first fixed guard 218. The second forward pivotal guard 220 pivots about the axis 222 of the circular saw blade 120. A spring (not shown) biases the second forward pivotal guard 220 downwardly (clockwise) as shown in
A bar 226 is pivotally attached at one end to the motor support 208 attached to the end of the guide rails 112, 116. An elongate slot 228 is formed along a section of the length of the bar 226 at the other end. A pin 230, rigidly attached to the second forward pivotal guard 220 passes through the slot 228 and which is capable of sliding along the slot 228. The biasing spring acting on the second forward pivotal guard 220 causes the guard to pivot until the pin 230 is at the inner end position of the slot where it remains held by the force of the spring. The pin 230 located within the slot 28 of the bar 26 controls the pivotal movement of the second guard 220 on the housing as it pivots upwards and downwards. When the housing 10 is in its upper most pivotal position (
A third rearward pivotal guard 232 is pivotally mounted about a point 234 on the rear of the first fixed guard 218. A spring (not shown) biases the third rearward pivotal guard 232 backwards (clockwise) as shown in
When the housing is raised to its upper pivot point (
When the motor unit 118 is pivoted downwardly, the second forward pivotal guard 220 is moved counterclockwise as shown in
Similarly, the third rearward pivotal guard 232 pivots once the tip 236 has engaged, allowing the edge of the blade 120 to pass through the third rearward pivotal guard 232, thus exposing the rear lower section of the blade 120 to cut the workpiece 216 (see
The first embodiment of height adjustment mechanism will now be described with reference to
Referring to
When the bolt is screwed into the threaded hole, it sandwiches the tubular support 440 against the casting 9 as the head of the bolt cannot pass through the slots 442, and prevents it from being able to slide in a vertical manner. In order to raise the height of the table 114 above the housing 410, the bolt is unscrewed slightly, so that the tubular support 440 can slide vertically, the sliding movement of the bolt along the elongate slot 442 controlling the movement of the tubular support 440. The height is then adjusted and then the bolt tightened to hold the tubular support 440, and hence table 114, stationary.
A second embodiment of the height adjustment mechanism is now described with reference to
Referring to
It is desirable to ensure that when the saw is being used to perform miter, bevel or chop cuts on a workpiece located on the rotatable table 104, maximum visibility is provided to the operated. In order to achieve this, the table ought to be raised to its maximum height while the saw is being used to perform such cuts. In order to ensure that the height of the table 114 is raised to its maximum above the rotatable table 104, a height adjustment mechanism has been incorporated. Referring to
When the table 114 is at its highest position, the lower end 514 of the strip 512 locates above the exposed end 508 of the locking rod 500. As such, when the table 114 is at its maximum height, the operator can freely slide the locking rod 500 within the tubular aperture 502. Therefore, when the motor unit is in its lowest position, the locking rod can be slid to lock or unlock the motor unit 118 to prevent or allow pivotal movement respectively of the motor unit 118 on the motor support 208. If the height of the table is reduced when the motor unit 118 is pivotally locked in it lowest position, the exposed end 508 of the locking rod 500 being located in its closest position to the motor support 208, the lower end 514 of the metal strip 512 passes the exposed end 508, causing a part of the metal strip 512 to locate adjacent the exposed end 508 of the locking rod 500, as such, the strip 512 prevents the locking rod 500 from being slid within the aperture 502 to withdraw the end from the recess, as movement of the exposed end 508 is blocked by the strip 512. As such, when the table 114 is not in its highest position, the motor unit pivot locking mechanism cannot be released and thus the motor unit 118 cannot be pivoted relative to the motor support 208 moved while the table 114 is not in its highest position. In order to release the motor unit pivot locking mechanism, the table 114 must be raised to its maximum height, in order to stop the strip 512 from blocking the movement of the locking pin 500.
If the motor unit pivot locking mechanism has been released while the table 114 is at its maximum height, the exposed end 508 of the locking rod moves to its most furthest position away from the motor support 208. In this position, the exposed end 508 is located beneath the lower end 514 of the strip 512. Therefore, if the table 114 is lowered, the lower end 514 of the strip 512 will engage with the exposed end 508 of the locking rod 500 and will then be prevented from moving further. This happens regardless of the angular position of the table 114 relative to the motor support 208. As such, the table 114 cannot be lowered when the motor unit pivot locking mechanism is released as the exposed end 508 of the locking rod 500 prevents the downward movement of the strip and hence the table 114. Therefore, in order to allow the height of the table 114 to be reduced, the motor unit pivot locking mechanism must be locked in order to move the exposed end 508 of the locking rod 500 out of the path of the strip.
As such, the table is always located at its maximum height when the motor unit 118 is capable of pivoting on the motor support 208.
Number | Date | Country | Kind |
---|---|---|---|
GB 06 151 50.0 | Jul 2006 | GB | national |