Pull Rod Release Mechanism for a Push-Pull Table Tool
In at least one embodiment, a table saw includes a table, a moveable carriage supported by the table, a saw assembly supported by the carriage, and a pull rod coupled to the carriage. The pull rod is configured to move in a linear direction relative to the housing between a back position and a forward position. The carriage and saw assembly move in the linear direction when the pull rod is moved in the linear direction. A collar is positioned on the pull rod and configured to move in the linear direction between a locked position and an unlocked position. The pull rod is configured to move in the linear direction from the back position toward the forward position when the collar is in the unlocked position, and the pull rod is blocked from moving from the back position when the collar is in the locked position.
This application is a divisional application of co-pending application Ser. No. 12/821,884, filed on Jun. 23, 2010 (now U.S. Pat. No. 8,474,358), the disclosure of such application which is totally incorporated by reference herein in its entirety.
TECHNICAL FIELDThis disclosure relates to the field of to table-top power tool devices operated with pull rods, and to table top saws in particular.
BACKGROUNDTable-top power tools are used in a wide variety of applications including wood working and metal working. Table-top power tools are typically mounted to a flat work surface, the table, configured to accept and guide work piece to the table-top tool. These power tools allow users to operate with more precision on larger work pieces than allowed with hand-held power tools. While table-top power tools are mounted to the table, the angle and position of the tool may be adjusted during operation. Some table-top power tools use one or more pull rods to change the position of the table top tool.
An example of a table-top power tool using a pull rod is a table saw which includes a circular saw blade. The circular saw blade extends through the table top surface, and a work piece, typically a piece of wood, is placed on the table top for cutting. The saw blade assembly is mounted on rails running along the length of the table, and the saw blade may be pushed or pulled along the rails in response to pushing or pulling on the pull rod. If the saw is activated, the spinning saw blade cuts through work pieces placed in its path on the table. In some existing table saws, the pull rod is also used to adjust the height of the circular saw blade. This adjustment is carried out by rotating the pull rod along its longitudinal axis in either a clockwise or counter-clockwise direction. The rotation of the pull rod increases and decreases the height of the saw blade above the table surface, depending upon the direction of rotation of the pull rod.
The pull rod may also be configured to lock the blade in a fixed position relative to table top in order to provide a rip saw mode of operation. In the rip saw mode, the pull rod locks the circular saw blade into a fixed position on the rails, and the work piece may then be moved over the saw-blade to cut the work piece.
The pull rod may also be configured to lock itself and the circular saw blade in place to allow for safety and/or transportation of the table saw with the blade in a secured position. Existing pull rods that are locked into position require two or more steps to unlock. For example, some known pull rod assemblies require a central button to be pushed in while simultaneously pulling outward on the pull rod to unlock it. These pull rod assemblies are generally difficult for an operator to unlock.
In view of the foregoing, it would be advantageous to provide a locking and unlocking mechanism for a pull rod assembly that permits unlocking the pull rod using fewer motions than traditional pull rod assemblies. It would also be advantageous to provide a locking and unlocking mechanism for a pull rod assembly configured to unlock the pull rod using few motions while permitting the pull rod to rotate on its longitudinal axis.
SUMMARYIn at least one embodiment, a table saw includes a table, a moveable carriage supported by the table, a saw assembly supported by the carriage, and a pull rod coupled to the carriage. The pull rod is configured to move in a linear direction relative to the housing between a back position and a forward position. The carriage and saw assembly move in the linear direction when the pull rod is moved in the linear direction. A collar is positioned on the pull rod and configured to move in the linear direction between a locked position and an unlocked position. The pull rod is configured to move in the linear direction from the back position toward the forward position when the collar is in the unlocked position, and the pull rod is blocked from moving from the back position when the collar is in the locked position.
In at least one embodiment, a table saw includes a table, a moveable carriage supported by the table, a saw assembly supported by the carriage, and a pull rod coupled to the carriage. The pull rod is configured to move in a linear direction relative to the housing between a back position and a forward position. The carriage and saw assembly move in the linear direction when the pull rod is moved in the linear direction, and a lock is configured to retain the pull rod in the back position. The lock includes an actuator configured to move in the linear direction between a locked position and an unlocked position. The pull rod is configured to move in the linear direction from the back position toward the forward position when the actuator is in the unlocked position, and the pull rod is blocked from moving from the back position when the actuator is in the locked position.
In at least one embodiment, a table tool with a retention mechanism includes a table having a table top, a carriage assembly coupled to the table top and movable in relation to the table top, and a pull rod assembly connected to the carriage assembly. The pull rod assembly is configured to move in a linear direction, and movement of the pull rod assembly in a linear direction results in movement of the carriage assembly in relation to the table top. The pull rod assembly includes a pull rod, a detent movably supported by the pull rod and positionable in a blocking position and a recessed position, and a collar movably positioned on the rod. The collar is engaged with the detent such that movement of the collar causes movement of the detent between the blocking position and the recessed position. The pull rod is inhibited from moving in the linear direction in relation to the table top when the detent is in the blocking position, and the pull rod is allowed to move in the linear direction in relation to the table top when the detent is in the recessed position.
For the purposes of promoting an understanding of the principles of the embodiments disclosed herein, reference will now be made to the drawings and descriptions in the following written specification. It is understood that no limitation to the scope of the subject matter is thereby intended. It is further understood that the present disclosure includes any alterations and modifications to the illustrated embodiments and includes further applications of the principles of the disclosed embodiments as would normally occur to one skilled in the art to which this disclosure pertains.
Referring to
Referring to
In the embodiment of
The pull rod assembly configuration of
In the configuration of
The pull rod assembly of
The pull rod assembly of
With continued reference to
Referring to
A push-pull table saw employing the pull rod locking assembly discussed above is depicted in
The saw 800 of
In a locked mode of operation a pull rod in a table top power tool is prevented from sliding in a linear direction by a locking detent disposed within a housing of a table. The locked pull rod may rotate in a clockwise or counterclockwise direction to further adjust the table top power tool. The pull rod assembly may be unlocked by an operator squeezing the collar against the pull rod handle while pulling the pull rod handle away from the housing in a linear direction matching the direction of movement of the table top tool. This motion continues until the locking detent button moves past the interior of the table housing, at which point the collar may be released.
In an unlocked mode of operation, a pull rod assembly may travel a linear direction toward or away from a housing of a table. A power tool such as a circular saw may move in response to movement of the pull rod. The unlocked pull rod may also rotate in a clockwise or counterclockwise direction to further adjust the position of the table top power tool. Upon the pull rod being released, a return spring urges carriage and the unlocked pull rod to return to the locked position with the detent inside of the housing. The detent button locks automatically with the detent button hole disposed inside the housing. The operator can release the pull rod any distance from the locked position during pulling and the carriage will retract automatically to the home back locked position In one embodiment, the pull rod handle contacts a bushing disposed on the exterior of the table housing when in the locked position.
The foregoing pull rod assembly has advantages over existing pull rod mechanisms. One advantage is that the pull rod may be unlocked by an operator by squeezing the collar and the pull rod handle together instead of requiring a more complex unlocking procedure. Another advantage is that, once unlocked, the pull rod returns to a locked position and the carriage is locked automatically when the pull rod is released by an operator.
While the invention has been illustrated and described in detail in the drawings and foregoing description, the same should be considered as illustrative and not restrictive in character. For example, while the disclosed embodiments are directed to a table saw, other table top tools including drill presses or lathes may be modified to use the pull rod locking assembly disclosed above. 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 invention are desired to be protected.
Claims
1. A table tool with a retention mechanism comprising:
- a table having a table top;
- a carriage assembly coupled to the table top and movable in relation to the table top;
- a pull rod assembly connected to the carriage assembly, the pull rod assembly configured to move in a linear direction, wherein movement of the pull rod assembly in a linear direction results in movement of the carriage assembly in relation to the table top, the pull rod assembly comprising: a pull rod; a detent movably supported by the pull rod and positionable in a blocking position and a recessed position; and a collar movably positioned on the rod, wherein the collar is engaged with the detent such that movement of the collar causes movement of the detent between the blocking position and the recessed position; wherein the pull rod is inhibited from moving in the linear direction relation to the table top when the detent is in the blocking position, and wherein the pull rod is allowed to move in the linear direction in relation to the table top when the detent is in the recessed position.
2. The table tool of claim 1 further comprising:
- a bushing connected to the table, the bushing having an interior side and an exterior side, and the pull rod extending through the bushing;
- a button hole formed in a portion of the rod with the detent positioned in the button hole.
3. The table tool of claim 1 wherein the detent further comprises a leaf spring and a detent button, the detent button attached to the leaf spring, wherein the detent is in the blocking position when the detent button is in an extended position in the button hole and the button hole is positioned on the interior side of the bushing.
4. The table tool of claim 3 further comprising a roll pin connected to the collar and engaging the leaf spring;
- the roll pin configured to move the leaf spring such that the detent button is moved to a recessed position in the button hole when the collar is moved in the linear direction away from the bushing; and
- the roll pin configured to allow the leaf spring to return the detent button to the extended position when the collar is moved in the linear direction towards the bushing.
5. The work tool of claim 3 wherein the detent button is a tapered detent button.
6. The work tool of claim 5 wherein the tapered detent button includes a beveled edge configured to engage the exterior side of the bushing and urge the detent button towards the recessed position when the collar is moved in the linear direction towards the bushing.
7. The work tool with a retention mechanism of claim 1 wherein the carriage assembly further comprises:
- a saw blade and a motor configured to rotate the saw blade.
Type: Application
Filed: Jul 2, 2013
Publication Date: Nov 7, 2013
Inventors: Robert S. Doumani (Hoffman Estates, IL), Jan Koegel (Arlington Heights, IL), Eric Hendrickson (Palatine, IL), Venu Samprathi (Barrington, IL), Brian Chung (Schaumburg, IL)
Application Number: 13/933,613
International Classification: B23D 45/06 (20060101);