DETECTEUR DE DEGRE D'ANGLE DE QUEUE D'ARONDE

DOVE TAIL ANGLE DEGREE FINDER

Abrégé anglais

This invention, called a Dove Tail Angle Degree Finder, is a mechanical
measuring device. It is a router application accessory enabling the operator
to find the specific degree of the cutting angle of dovetail router bits.
Distinct dovetail applications require specific degrees. The degree of
the cutting angle is usual not marked on the router bit's shaft. A custom
ground or resharpened bit also has a specific cutting angle.
This invention is very handy in a shop with an inventory of many
different dovetail bits.
Bits can be specified in a frustration less, fast and accurate way.

Revendications

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1: A Device enabling one to find and measure the degree of
dovetail router bits and other non parallel objects.
2: A stationary jaw affixed to .alpha.. sliding bar
3: The stationary jaw as defined in claim 2 is to be furnished with a
plate at it's inner side whereby creating a large surface area for the router
bit to rest against.
4: A specially shaped movable jaw which is riding on the sliding bar
as defined in claim 2.
5: A hole through the bottom-tip is to be furnished to the specially
shaped movable jaw as defined in claim 4 to hold the pin and coil spring for
the clocklike hand.
6: A clocklike hand is to be installed v1a a coil spring to said hole as
defined in claim 5.
7: A stopper has to be furnished on the movable jaw in order for the
spring loaded clock like hand to rest in it's zero degree reading position.
8: A scale with increments of dovetail-bit degree measurements is
to be incorporated and located at the prober distance for the tip of the
clocklike hand as defined in claim 6 to show the readings.
9: A tension spring is to pull the movable jaw toward .alpha. closed
position.

Description

CA 02313898 2000-07-17
Background of the Invention
To find the proper angle bit and to be sure it is of the exact required angle
was a bit guess work, frustrating and timely. To grind a specific bit In order
to
match the angle of an existing work piece was equally time consuming. This
phenomena led me to the idea of this invention.
Description of the Preferred Embodiments
The following detailed description illustrates embodiments
of the invention by way of example and not by way of limitation.
This description will clearly enable one to make, use and install
this invention.
This Invention is implemented by the use of a sliding bar with two jaws,
similar in appearance to that of a vernier caliber. One jaw is secured to the
sliding bar and the other jaw moves along said sliding bar.
The secured jaw's inner-side is furnished with a plate which increases its
surface area.
The sliding jaw's inner-side is designed to be slanted by approximately
35 degrees. The purpose of this pattern is to allow only the bottom tip of the
movable jaw's inner-side to come in contact with the secured jaw's inner-side
when closed. A hole has to be furnished near the bottom tip of the sliding
jaw. A clock-like hand is to be installed via a spring loaded pin to said
hole.
This spring loaded pin contains a coil spring which brings the hand back to
it's


CA 02313898 2000-07-17
standard zero degree position. A stopper is to be incorporated for the hand
to rest at the zero degree position.
A scale with one degree increments is marked on the sliding bar. The
scale Is located opposite to the sliding jaw's hand installation. When an ob-
ject is placed between the jaws, the hand moves to indicate the proper de-
gree reading.
An optional tension-spring may be used to pull the sliding jaw assem-
bly to the closed position.
Remarks: The angle degree specification on dovetail bits refer to the rela-
tionship between shaft and one cutting edge of the router bit. This has to be
taken into account when calculating the scale increments. Since the hand
shows the total V-shope of the dovetail bit, which is double the bit measure-
ment, the increments on the device are half degrees in order to display stan-
dard bit measurements.
The sliding bar can be made of any material, and in any shape.
The jaws functions can also be reversed. All these changes or modifica-
tlons do not have any merit on the distinctiveness of this invention being a
dove tall angle degree finder.
The operation of this device is best performed by using two hands, un-
less this device is made or fastened to be stationary.
To insert the bit the jaws must be pulled apart. If not installed with the
optional closing spring the jaw must be closed manually.
The device works as follows:


CA 02313898 2000-07-17
The dovetail bit is placed with the cutting edge firmly against the flat
plate surface off the fixed jaw. Make sure that the bit shaft is all the way
outside of this jaw. The closed sliding jaw forces the hand to move which
compensates for the bit angle. The measurements of the dovetail bit are ob-
tained from the degree scale reading. Other objects of non parollel shafts
can of course also be measured.

Dessin représentatif