Circular saw blade inspection device
View Patent ↗A device and method for inspecting circular saw blades and measuring certain physical qualities of circular saw blades is provided. The device includes a holder for mounting a circular saw blade onto the device, a distance indicator for indicating relative movement of the saw blade when mounted, and opposing electromagnets for inducing movement of portions of the saw blade to measure tension in the blade.
1 . A device comprising:
a holder configured to removably secure a saw blade to the holder, wherein the holder is further configured to rotate about an axis of rotation such that the saw blade is rotatable about the axis of rotation when the saw blade is secured to the holder, wherein the saw blade has a central bore opening, wherein a center of the central bore opening defines the axis of rotation when the saw blade is secured to the holder;
two opposing electromagnets each mounted in a position adjacent to a surface of the saw blade on a same side of the saw blade when the saw blade is secured to the holder, wherein the two opposing electromagnets are disposed adjacent to respective portions of the surface of the saw blade that are disposed on opposing sides of the central bore opening when the saw blade is secured to the holder, wherein the two opposing electromagnets are disposed at an angle of about 180 degrees from each other relative to the axis of rotation such that the two opposing electromagnets are linearly aligned with each other along a line that intersects the axis of rotation; and
a distance indicator mounted in a position adjacent to the surface of the saw blade and configured to indicate variations of distance of the surface of the saw blade relative to the distance indicator when the saw blade is secured to the holder,
wherein the two opposing electromagnets are each mounted in a position relative to the surface of the saw blade such that there is a gap between each of the two opposing electromagnets and the surface of the saw blade when an electric current to each of the two opposing electromagnets is turned off with the saw blade secured to the holder, wherein the two opposing electromagnets are configured to cause the surface of the saw blade to contact both of the two opposing electromagnets when the electric current to each of the two opposing electromagnets is turned on to induce a magnetic field, and
wherein the two opposing electromagnets are further configured to cause the saw blade to flex when the electric current is turned on to induce a magnetic field, thereby causing surface deflections of the surface of the saw blade, and wherein the distance indicator is further configured to measure the surface deflections.
2 . The device of claim 1 , wherein the holder comprises a permanent magnet configured to removably secure the saw blade to the holder.
3 . The device of claim 1 , wherein the holder is configured to removably secure the saw blade to the holder in a position in which the saw blade is retained in a substantially vertical plane.
4 . The device of claim 1 , wherein the two opposing electromagnets are vertically aligned with each other.
5 . The device of claim 4 , wherein the position of each of the two opposing electromagnets is vertically adjustable.
6 . The device of claim 1 , wherein the holder is mounted onto an axle that defines the axis of rotation, wherein an axial position of the axle is axially adjustable such that a width of the gap is adjustable by adjusting the axial position of the axle.
7 . The device of claim 1 , wherein the distance indicator comprises a dial indicator.
8 . The device of claim 1 , wherein the position of the distance indicator is linearly adjustable along a line that is generally perpendicular to the axis of rotation.
9 . The device of claim 8 , wherein the line along which the position of the distance indicator is linearly adjustable is generally horizontal.
10 . The device of claim 1 , wherein the position of the distance indicator is linearly adjustable along a line that is generally perpendicular to a line extending directly between the two opposing electromagnets.
11 . The device of claim 1 , wherein the position of the distance indicator is about 90 degrees from the position of each of the two opposing electromagnets relative to the axis of rotation.
12 . The device of claim 1 , wherein the holder comprises a handle configured to allow manual rotation of the holder about the axis of rotation.
13 . The device of claim 1 , wherein the distance indicator is further configured to measure the surface deflections in a location of the surface of the saw blade that is about 90 degrees from both of the two opposing electromagnets relative to the axis of rotation.
14 . A method of measuring tension of a circular saw blade, said method comprising the steps of:
providing a device comprising:
a holder configured to removably secure a saw blade to the holder, wherein the holder is further configured to rotate about an axis of rotation such that the saw blade is rotatable about the axis of rotation when the saw blade is secured to the holder, wherein the saw blade has a central bore opening, wherein a center of the central bore opening defines the axis of rotation when the saw blade is secured to the holder,
two opposing electromagnets each mounted in a position adjacent to a surface of the saw blade on a same side of the saw blade when the saw blade is secured to the holder, wherein the two opposing electromagnets are disposed adjacent to respective portions of the surface of the saw blade that are disposed on opposing sides of the central bore opening when the saw blade is secured to the holder, wherein the two opposing electromagnets are disposed at an angle of about 180 degrees from each other relative to the axis of rotation such that the two opposing electromagnets are linearly aligned with each other along a line that intersects the axis of rotation, and
a distance indicator mounted in a position adjacent to the surface of the saw blade and configured to indicate variations of distance of the surface of the saw blade relative to the distance indicator when the saw blade is secured to the holder,
wherein the two opposing electromagnets are each mounted in a position relative to the surface of the saw blade such that there is a gap between each of the two opposing electromagnets and the surface of the saw blade when an electric current to each of the two opposing electromagnets is turned off with the saw blade secured to the holder, wherein the two opposing electromagnets are configured to cause the surface of the saw blade to contact both of the two opposing electromagnets when the electric current to each of the two opposing electromagnets is turned on to induce a magnetic field,
wherein the two opposing electromagnets are further configured to cause the saw blade to flex when the electric current is turned on to induce a magnetic field, thereby causing surface deflections of the surface of the saw blade, and wherein the distance indicator is further configured to measure the surface deflections;
deactivating the two opposing electromagnets;
removably securing the saw blade to the holder such that there is a gap between each of the two opposing electromagnets and the surface of the saw blade;
activating the two opposing electromagnets by supplying an electric current to each of the two opposing electromagnets to induce a magnetic field, thereby causing the saw blade to flex due to opposing first portions of the saw blade being magnetically drawn toward and contacting each of the two opposing electromagnets to cause surface deflections of the surface of the saw blade; and
using the distance indicator, measuring the surface deflections by measuring a relative distance differential of a second portion of the saw blade relative to a first position of the second portion in which the two opposing electromagnets are deactivated and a second position of the second portion in which the two opposing electromagnets are activated.
15 . The method of claim 14 , further comprising the steps of rotating the saw blade when the two opposing electromagnets are deactivated and using the distance indicator to measure variations of distance of the surface of the saw blade relative to the distance indicator as the saw blade rotates.
16 . The method of claim 14 , wherein the holder comprises a permanent magnet configured to removably secure the saw blade to the holder, wherein the step of removably securing the saw blade to the holder comprises magnetically securing the saw blade to the permanent magnet.
17 . The method of claim 14 , wherein the position of the distance indicator is linearly adjustable between an eye of the saw blade and an outer rim of the saw blade, wherein the method further comprises the step of adjusting the position of the distance indicator.
18 . The method of claim 14 , wherein the second portion of the saw blade defines a location of the surface of the saw blade at which the distance indicator measures the surface deflections, wherein the location of the second portion is about 90 degrees from both of the two opposing electromagnets relative to the axis of rotation.