Slide mechanism and rip fence of table saw

A table saw includes a slide mechanism on a table assembly and including a knob, front and rear roller pinions, two slides slidably secured to front and rear ends of the table respectively, each slide having a bottom rack engaging the roller pinion, a groove on an outer surface, and projections projecting out of the groove, front and rear mounting members secured to the table, and an axle; and a rip fence assembly on either side of the table assembly and including front and rear arms each having a cavity for releasably securing to one projection, a rip fence between the arms, front and rear risers respectively for fastening either end of the rip fence and either one of the front and rear arms, and two levers on the arms respectively, each lever including an upper pivot, an intermediate urging protuberance, and a lower protrusion.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to table saws and more particularly to a rack and roller pinion driven slide mechanism having improved characteristics and a rip fence also having improved characteristics.

2. Description of Related Art

U.S. Pat. No. 9,095,989 to Chang, entitled “rip fence with locking mechanisms”, discloses a table saw including a movable rip fence and a base including an upper cutting surface through which a blade extends. The rip fence includes front and rear clamping mechanisms connected to front and rear ends of a casing respectively. The front clamping mechanism includes a frame, a lever pivotably secured to the frame to be pivotal between a locked position and a released position, the lever having an internal cam member, a clamping member pivotably secured to the lever, the clamping member having a hook at an open end, a spring biased shaft, and a C-clip for retaining an inner end of the shaft in the frame. A pivotal movement of both the lever and the clamping member causes the cam member to push the shaft inward until the shaft is pushed outward to urge against the cam member in the locked position.

U.S. Pat. No. 9,731,432 to Chang, entitled “rip fence with locking device”, discloses a moveable rip fence of a table saw comprising a housing including an elongated top opening, a seat secured to an underside of top of the housing, the seat having a lower through hole, and a stop member across two sides of the housing, a lever pivotably fastened in the elongated opening; a link pivotably interconnecting the lever and a spring biased rod, an inverted L-shaped limit member secured across two sides of the housing; a clamping member having a top secured by a support member and including an intermediate hole member and a projecting base member; and a locking member including a lower wedge member fastened on the base member, and a flexible inclined member on a top. The lever is flush with the top of the housing in a locked position. A pressing of a rear portion of the lever unlocks the rip fence.

U.S. Pat. No. 10,183,415 to Chang, entitled “table saw”, discloses a table saw comprising a table, a saw, a track, a slide strip, and a fence member. The table has an axial direction and a radial direction which are orthogonal to each other. The saw is arranged at a predetermined position of the table. The track is arranged at each side of the table. The slide strip is slidably engaged with the track. An outer surface of the slide strip opposite to the track has a first position part, a second position part, and a third position part. The first position part and the second position part are respectively arranged at two ends of the slide strip and the third position part is arranged at a center of the slide strip. The fence member is bridged on the table and secured to one of the first position part, the second position part, and the third position part.

While the table saws enjoy their success in the market, continuing improvements in the exploitation of table saw of this type are constantly being sought.

SUMMARY OF THE INVENTION

It is therefore one object of the invention to provide a table saw comprising a base assembly; a table assembly mounted on the base assembly and including a table; a slide mechanism mounted on the table assembly and including a knob, front and rear roller pinions adjacent to the knob, front and rear mounting members secured to a bottom of the table and being adjacent to the front and rear roller pinions, two slides slidably secured to front and rear ends of the table respectively, each slide having a bottom rack engaging either one of the front and rear roller pinions, and an axle mounted under the table and having two ends attached to the front and rear roller pinions respectively so that the axle is configured to rotatably pass through the front and rear mounting members; and a rip fence assembly mounted on either side of the table assembly and including a lengthwise groove on an outer surface, a plurality of projections projecting out of the groove, front and rear arms each having a cavity at an open end configured to releasably secure to one of the projections, a rip fence disposed between the arms, front and rear risers respectively for fastening either end of the rip fence and either one of the front and rear arms, and two levers disposed on the arms respectively, each lever being adjacent to the cavity and including a spring biased pivot at an upper end, an intermediate urging protuberance, and a lower protrusion.

DETAILED DESCRIPTION OF THE INVENTION

Referring toFIGS. 1 to 22B, a table saw1in accordance with the invention comprises a base assembly10, a table assembly20mounted on the base assembly10, a slide mechanism30mounted on both the base assembly10and the table assembly20, and a rip fence assembly40mounted on the right side of the table assembly20as discussed in detail below.

Alternatively, the rip fence assembly40is mounted on the left side of the table assembly20(seeFIG. 11) or a short distance from the right side of the table assembly20(seeFIG. 12).

The table assembly20includes a table21.

The rip fence assembly40includes front and rear arms42each having a cavity421at an open end; and a rip fence41between the arms42, and front and rear risers44in which the front riser44is used to secure the front arm42and one end of the rip fence41together, and the rear riser44is used to secure the rear arm42and the other end of the rip fence41together.

The slide mechanism30includes a knob31, front and rear roller pinions32each adjacent to the knob31, an axle33mounted under the table21and having two ends attached to the roller pinions32respectively so that the knob31, the roller pinions32and the axle33may co-rotate. The slide mechanism30further comprises front and rear mounting members34secured to the bottom of the table21and being adjacent to the roller pinions32. The axle33rotatably passes through the front and rear mounting members34.

The slide mechanism30further comprises two slides35slidably secured to front and rear ends of the table21respectively, each slide35having a rack351on a bottom, the rack351engaging teeth of the corresponding roller pinion32, a lengthwise groove352on an outer surface, and a plurality of projections353projecting out of the groove352for releasably inserting into the cavity421.

As shown inFIG. 5Bspecifically, a clockwise rotation of the knob31clockwise values the roller pinions32. And in turn, the racks351move rightward. As a result, both the slides35and the arms42move rightward. To the contrary, a counterclockwise rotation of the knob31counterclockwise rotates the roller pinions32. And in turn, the racks351move leftward. As a result, both the slides35and the arms42move leftward.

Two levers43are provided on the arms42respectively. The lever43is adjacent to the cavity352. The lever43includes a pivot431at an inner, upper end, and a torsion spring432put on the pivot431and secured to both the lever43and the arm42so that the lever43may pivot about the pivot431, i.e., the lever43being pivotably secured to the arm42. The lever43further comprises an inner, intermediate urging protuberance433and an inner protrusion434under the urging protuberance433.

In a locking operation, an employee may pivot the lever43downward to urge the urging protuberance433against a resisting surface422of the arm42and insert the protrusion434into an opening423of the arm42to urge against the slide35. As a result, both the arm42and the slide35are locked by the lever43.

To the contrary, in an unlocking operation, an employee may pivot the lever43upward to disengage the urging protuberance433from the resisting surface422of the arm42and disengage the protrusion434from the opening423of the arm42. As a result, both the arm42and the slide35are unlocked by the lever43and thus the slide35is allowed to slide.

Operation of securing the rip fence assembly40to the slide35(i.e., the slide mechanism30and the table assembly20) is discussed inFIGS. 13, 14A, 14B, 14C,15A,15B,15C,16A,16B and16C.

As shown inFIGS. 17 to 18B, a non-use state of an elongated, rectangular metal plate50is shown. The metal plate50includes two mounting elements51at two ends respectively. The mounting element51includes a first positioning hole511, a second positioning hole512and an oval slot513at an open end and releasably put on a pivot411at either end of the rip fence41. The riser44includes an upper positioning member (e.g., steel ball)441disposed at the mouth of a first hole442, a first helical spring443anchored in the hole442, a lower positioning member (e.g., steel ball)444disposed at the mouth of a second hole445, and a second helical spring446anchored in the second hole445. Thus, in the non-use state of the metal plate50, the spring biased upper positioning member441is inserted into the first positioning hole511, and the pivot411is at one end of the slot513.

As shown inFIGS. 19 to 21B, a use state of the metal plate50is shown. As shown inFIGS. 20A and 20Bspecifically, the metal plate50is flush with the table21, the spring biased lower positioning member444is inserted into the second positioning hole512, and the pivot411is at one end of the slot513.

As shown inFIGS. 21A and 21Bspecifically, bottom of the metal plate50is flush with the table21, the spring biased lower positioning member444is inserted into the first positioning hole511, and the pivot411is at the other end of the slot513.

As shown inFIGS. 22A and 22Bspecifically, a tool60is received in a space412of the hollow rip fence41. In detail, an anchor member413is secured to a wall of the space412, the anchor member413including a shaft4131and an enlargement4132at an end of the shaft4131; a clip414is also secured to the wall of the space412, the clip414being configured to clamp the tool60; and the tool60includes a plurality of sets of a larger hole601tightly put on the enlargement4132, and a smaller hole602tightly put on the shaft4131. As a result, the tool60is fastened in the rip fence41.