This application claims priority under 35 U.S.C. ยง 119 to patent application number IN 201841020446 filed on May 31, 2018 in India, the disclosure of which is incorporated herein by reference in its entirety.
The present invention relates to a holder assembly for a circular saw tool.
According to a prior art US 2010/0040474, a fixing device for rotary blade is provided. A fixing device for fixing a rotary blade to a spindle in a bench circular saw, for example, has a structure in which it is difficult to achieve structural compactification in radial size. Therefore, there has been a problem of sacrificing an inclination angle and a cutting depth of the rotary blade. Provided is a fixing device free from such problems owing to employment of a structure which can be easily compactified in a radial direction. Cam portions are provided on respective surfaces opposite to each other of an intermediate flange and an outer flange so as to mesh with each other. The cam portions slide with each other with a rotational force imparted to the rotary blade so that the rotational force is converted into a displacement in a direction of an axis of the intermediate flange and is applied in a direction of clamping the rotary blade.
An embodiment of the disclosure is described with reference to the following accompanying drawings,
The blade 116 is mounted over the at least one clutch member 108 and then held between the inner flange 106 and the outer flange 110 with the help of a washer 112 and a bolt 114.
The at least one clutch member 108 is adapted to brake rotation of the blade 116 under emergency conditions. One of the emergency condition may be presence of a body part of a human operator in proximity or in contact with the rotating blade 116. The braking or stopping of the rotation of the shaft 102, under emergency conditions is performed by separate devices or systems known in the art.
In accordance to another embodiment of the present invention, at least one clutch member 108 comprises three clutch members 108, paired and mounted about respective three depressions 104 as shown in
Further, the inner flange 106 comprises at least one protrusion 202 acting as guide to position the at least one clutch member 108. The guide assist in placement of the at least one clutch member 108 in a fitting manner. In
The circular saw tool is selected from a group comprising a table-top tool, a portable tool, a hand-held tool, a plunge tool and the like. In an embodiment, the holder assembly 100 is retrofit to existing circular saw tools.
A working of the holder assembly according to the present invention is disclosed. When the circular saw tool is in operation, the complete holder assembly 100 is rotated. When the shaft 102 stops suddenly with external mechanism called brake, the blade 116 tends to rotate due to inertia as it is held in place with inner flange 106 and the outer flange 110. The sub-assembly of the blade 116, the inner flange 106 along with the clutch members 108 tend to rotates due to the inertia of the blade 116. As the clutch members 108 rotate rotates on the shaft 102 due to motion input from the inner flange 106, the clutch members 108 tend to move radially out and grip the internal surface of the blade 116 by harder gripping force as blade 116 tends to rotate further. The gripping enhances as the clutch members 108 move on the depression 104 or profile of the shaft 102. Hence, the mechanism converts moment of inertia of the blade 116 into higher gripping of the blade 116 during deceleration. As the blade 116 stops, the gripping force tends to reduce as the clutch members 108 are held in place with the restraining element 402.
In accordance to an embodiment of the present invention, the holder assembly 100 provides improved gripping while safety or emergency braking with easy access to the blade 116 and also reduces efforts for changing the blade 116. Further, the mounting and demounting torque required for the blade 116 is within normal human limit. The holder assembly 100, enhances safety braking mechanism by hard gripping blade 116 at braking event. Also, the temperature of blade 116 does not rise as the rotation of the blade 116 is stopped instantly.
It should be understood that embodiments explained in the description above are only illustrative and do not limit the scope of this invention. Many such embodiments and other modifications and changes in the embodiment explained in the description are envisaged. The scope of the invention is only limited by the scope of the claims.
Number | Name | Date | Kind |
---|---|---|---|
2239623 | Oster | Apr 1941 | A |
2308679 | Eason | Jan 1943 | A |
2491976 | Hauser | Dec 1949 | A |
2947399 | Moore | Aug 1960 | A |
3067597 | Sauerbrey | Dec 1962 | A |
3857180 | Dooley | Dec 1974 | A |
4033038 | Lunde | Jul 1977 | A |
4044533 | Wick | Aug 1977 | A |
4220064 | Potter | Sep 1980 | A |
4253556 | Zindler | Mar 1981 | A |
4414875 | Pearson | Nov 1983 | A |
5293798 | Otani | Mar 1994 | A |
5560465 | Zindler | Oct 1996 | A |
6439091 | Dibbern | Aug 2002 | B1 |
7510062 | Derr | Mar 2009 | B2 |
10570966 | Carlson | Feb 2020 | B2 |
20100040474 | Takahashi et al. | Feb 2010 | A1 |
20110048197 | Winkler | Mar 2011 | A1 |
Number | Date | Country | |
---|---|---|---|
20190366578 A1 | Dec 2019 | US |