Patent Application
20130160623
The present disclosure relates generally to power saws, and particularly to power saws having a debris collection system.
One type of cutting tool is a power saw that includes an electrical motor mounted below a work surface. Users frequently refer to this type of power saw as a table saw, because the work surface resembles a tabletop. The table has an opening that allows a portion of the cutting tool, such as a saw blade, to extend above the surface of the table. The blade, which is rotatably connected to the electrical motor, is movable relative to the surface of the table to enable a user of the table to make cuts of a particular depth or angle. For example, to adjust the height of the blade, a user may position a workpiece adjacent to the blade and then adjust the height of the blade such that the apex of the blade extends just above the thickest portion of the workpiece. To cut the workpiece, a user positions the workpiece on the table, such that a line representing the cutting path of the blade is aligned with a region of the workpiece to be cut, energizes the motor to rotate the blade, and moves the workpiece toward the rotating blade. As the blade cuts through the workpiece, it generates dust, chips, and other workpiece debris, which may be collected by a debris collection system.
Table saw debris collection systems, commonly referred to as dust collectors, direct the workpiece debris into a collection receptacle such as a porous bag or other suitable container. Additionally or alternatively, an external negative pressure source, such as a vacuum may be configured to draw the debris from a debris exit port of the table saw into a container. Some users, however, may desire a table saw having a dust collector, which functions effectively without a separate negative pressure source.
In some cases the user may not apply vacuum to the debris exit port, for example when a vacuum source is unavailable. In this instance, the debris may not be adequately discharged through the exit port while the blade is operating, which can lead to clogging of the debris collection system and even to binding of the blade. The user is then required to turn off the power tool and manually attempt to dislodge the debris through the exit port or disassemble the dust collection system to clean out the debris and dust. Accordingly, further developments in the area of table saw dust collection systems are desirable.
A power tool includes a table structure defining a blade slot, a frame supporting the table structure, a blade assembly mounted within the frame, and a carriage assembly. The blade assembly includes a blade positioned within the blade slot and a motor assembly to rotate the blade, in which the carriage assembly supports the motor assembly relative to the table structure. The carriage assembly defines a chamber within which said blade operates and a discharge chute for discharge of dust and debris from the chamber during operation of the blade. The bottom wall of the carriage assembly below said blade defines one or more openings that are sized to permit passage of the dust and debris and to comply with finger probe test safety standards. In certain embodiments, the openings may be provided with a cover that is movable to expose or close the openings. The cover may be pivotably, slidably or rotatably mounted to the carriage assembly to move between a position closing the openings and a position in which the openings are exposed for removal of debris therethrough.
In certain embodiments, the one or more openings include a plurality of elongated slots that extend along a substantial portion of the length of the bottom wall. In embodiments with a cover, the cover may be slidably mounted within certain of the elongated slots. In other embodiments, the openings include a plurality of arc segment openings. In these embodiments, the cover may be rotatably mounted over the openings with arc segment openings that coincide with the openings in the bottom wall when rotated to a certain position.
Features of the present disclosure should become apparent to those of ordinary skill in the art to which this device pertains from the following description with reference to the figures, in which:
For the purpose of promoting an understanding of the principles of the device described herein, reference is made to the embodiment(s) illustrated in the figures and described in the following written specification. It is understood that no limitation to the scope of the device is thereby intended. It is further understood that the device includes any alterations and modifications to the illustrated embodiment(s) and includes further applications of the principles of the device as would normally occur to one of ordinary skill in the art to which this device pertains.
As shown in
In certain embodiments, the blade assembly 101 has a fixed position along the longitudinal axis L of the table 102 or along the length of the slot 106. In other embodiments, the blade assembly 101 may be mounted to a slide assembly (not shown) that enables the blade assembly longitudinally relative to the table 102, commonly referred to as a “push-pull” saw.
The blade assembly 101 of the table saw 100 includes an adjustment mechanism 110 for adjusting the angular and vertical position of the blade. The mechanism 110 is adapted to permit rotation of the blade assembly 101 about the longitudinal axis L so that the blade can make an oblique cut in the workpiece. The mechanism may be further adapted to raise and lower the cutting blade relative to the table 102 to adjust the depth of the cut into the workpiece.
As shown in
The adjustment mechanism 110 incorporates a mechanism for controlled pivoting of the carriage assembly 124 relative to the table 102, and for controlled up and down movement of the motor assembly 122 relative to the table, which ultimately provides for controlled positioning of the cutting blade 120. It can be appreciated that a variety of adjustment mechanisms may be utilized to provide the angular and up-down adjustments for the blade 120. For instance, a lead screw mechanism may be provided to move the motor assembly 122, and thus the blade 120, up and down relative to the carriage assembly 124 and thus relative to the table 102 and work surface. The angular adjustment mechanism may incorporate a locking pin, such as pin 112, engaged within a curved slot 113 in a side wall 114 of the frame 104. Other mechanisms are contemplated provided they are at least capable of adjusting the angle of the blade 120 relative to the table 102 and slot 106.
The carriage assembly 124 and cover 126 define a chamber 129 within which the blade 120 rotates when it is mounted to the motor assembly 122. The chamber 129 includes a discharge chute 130 defined at a lower portion of the chamber to direct dust and debris to an outlet 132, as shown in
The carriage assembly 124 and more particularly the chamber 129 and chute 130, are configured to contain and convey the majority of the dust and debris when the blade 120 is operated. However, these features have their greatest utility when coupled to a vacuum or suction source at the outlet 132. In some cases, the user may not apply vacuum, such as when working outdoors or where a vacuum source is not available. While some of the dust and debris may be discharged from the open outlet 132, dust will typically tend to accumulate within the discharge chute 130. If the outlet 132 is clogged, the dust will continue to build up within the chamber 129 until the saw blade is impeded. The user must then find some way to remove the built up dust and debris, which involves shutting the power tool down and opening the carriage assembly 124 or poking an instrument through the outlet 132 to scrape out the dust and debris from the discharge chute 130. It can be appreciated that this method for clearing the carriage assembly can be time consuming and frustrating for the user.
In accordance with one aspect of the present disclosure, the carriage assembly 124 is provided with openings that allow passage of dust and debris from the carriage assembly while still protecting the user from the blade. Thus, in one embodiment shown in
The openings 142 may assume various configurations, provided that they have sufficient area to allow passage of at least saw dust and are sufficiently small to pass the finger probe test. In the embodiment shown in
In the illustrated embodiment the openings 142 are shown without any closure. Thus, the openings 142 remain open even when vacuum or suction is applied at the outlet 132. However, it may be desirable to close the openings when suction is used so that all of the dust and debris is ejected through the outlet 132. The present disclosure thus contemplates the addition of a movable closure for the openings.
In one embodiment, a movable door 150 is provided that is configured to cover the openings 142, as shown in
In another embodiment, a sliding cover 160 may be provided, as shown in
As an alternative to engaging within the slots themselves, the prongs 161 of the cover 160 may be arranged to engage grooves in the carriage assembly. For example, grooves may be provided in the side walls of the carriage assembly with the prongs on the cover configured to wrap around the bottom wall 140 to engage the grooves. With this construction, the prongs do not interfere with the openings 142. The grooves and prongs may be configured to ensure a close running fit between the cover 160 and the openings.
In a further embodiment, a rotating cover 170 may be provided as shown in
The devices and apparatuses described herein has been illustrated and described in detail in the figures and foregoing description, the same should be considered as illustrative and not restrictive in character. It is understood that only the preferred embodiments have been presented and that all changes, modifications, and further applications that come within the spirit of the device described herein are desired to be protected.
