Polycrystalline diamond (PCD) laser lapping machine
A laser lapping machine has a platform for supporting and rotating a product, and a laser device for transmitting a laser beam onto the surface of the product. The product may contain polycrystalline diamond, and the platform and the laser device may be configured to move a cutting point along a spiral path across the product surface. A process for removing material, such as polycrystalline diamond material, from a surface of a product is also described. The process includes transmitting a laser beam onto the product surface to remove the material at a cutting point, rotating the product surface relative to the laser beam, and causing the cutting point to move in a radial direction. According to one aspect of the present disclosure, rotation of the platform and radial movement of the laser beam cause the cutting point to move along a spiral path across the product surface.
1 . A laser processing machine comprising:
a platform configured to support and rotate a product;
a laser device configured to transmit a laser beam onto a top surface of the product, the laser beam having: an angle α between a central axis of the laser beam and a plane parallel to the platform, and a cone with a convergence angle β; and
a controller configured to control the laser device and rotation of the platform;
wherein the controller is configured to control the laser device and rotation of the platform to move a cutting point of the laser beam along a spiral path across the product while maintaining the angle α: greater than one half of the convergence angle β, and in a range from 3° to 7°, inclusive.
2 . The machine of claim 1 , wherein the platform has three seats for supporting the product on the platform.
3 . The machine of claim 1 , further comprising an exhaust system for removing debris and gaseous products created by the laser beam at the cutting point.
4 . The machine of claim 1 , further comprising a sensor for sensing light and/or sound created by the laser beam at the cutting point.
5 . The machine of claim 4 , wherein the controller is operatively connected to the platform and the laser device, and wherein the controller is further configured to control a rate at which the cutting point moves along the spiral path based on signals from the sensor, such that the cutting point moves at a first speed when active cutting of the top surface is detected by the sensor and at a second speed greater than the first speed when active cutting of the top surface is not detected by the sensor.
6 . A process for removing material from a top surface of a product, the process comprising:
supporting the product on a rotatable platform;
transmitting a laser beam at an angle α onto the top surface of the product to remove the material at a cutting point on the top surface of the product, the laser beam having the angle α between a central axis of the laser beam and a plane parallel to the platform, and a cone with a convergence angle β; and
rotating the platform to rotate the top surface of the product relative to the laser beam, and moving the laser beam to move the cutting point in a radial direction relative to the top surface of the product, such that the cutting point follows a spiral path across the top surface of the product while maintaining the angle α: greater than one half of the convergence angle β, and in a range from 3° to 7°, inclusive.
7 . The process of claim 6 , further comprising using three seats to support the product on the platform.
8 . The process of claim 6 , further comprising using an exhaust system to remove debris and gaseous products created by the laser beam at the cutting point.
9 . The process of claim 6 , further comprising using a sensor to sense light and/or sound created by the laser beam at the cutting point.
10 . The process of claim 9 , further comprising using the sensor to control a speed at which the cutting point moves relative to the top surface of the product.
11 . The process of claim 9 , further comprising controlling a rate at which the cutting point moves along the spiral path based on signals from the sensor, such that the cutting point moves at a first speed when active cutting of the top surface is detected by the sensor and at a second speed greater than the first speed when active cutting of the top surface is not detected by the sensor.
12 . A laser lapping process for removing polycrystalline diamond material from a top surface of a product, the process comprising:
supporting the product on a rotatable platform;
transmitting a laser beam at an angle α onto the top surface of the product to remove the polycrystalline diamond material at a cutting point on the top surface of the product, the laser beam having the angle α between a central axis of the laser beam and a plane parallel to the platform, and a cone with a convergence angle β; and
rotating the platform to rotate the top surface of the product relative to the laser beam, and simultaneously moving the laser beam to move the cutting point in a radial direction relative to the top surface of the product, such that the cutting point follows a spiral path across the top surface of the product while maintaining the angle α: greater than one half of the convergence angle β, and in a range from 3° to 7°, inclusive.
13 . The laser lapping process of claim 12 , further comprising using three seats to support the product on the platform.
14 . The laser lapping process of claim 12 , further comprising using an exhaust system to remove debris and gaseous products created by the laser beam at the cutting point.
15 . The laser lapping process of claim 12 , further comprising using a sensor to sense light and/or sound created by the laser beam at the cutting point.
16 . The laser lapping process of claim 15 , further comprising using the sensor to control the speed at which the cutting point follows the spiral path.
17 . The laser lapping process of claim 15 , further comprising controlling a rate at which the cutting point moves along the spiral path based on signals from the sensor, such that the cutting point moves at a first speed when active cutting of the top surface is detected by the sensor and at a second speed greater than the first speed when active cutting of the top surface is not detected by the sensor.
18 . The laser lapping process of claim 12 , wherein the product is a disk.
19 . The laser lapping process of claim 12 , wherein the product is a cylinder.
20 . The laser lapping process of claim 12 , wherein the polycrystalline diamond material is located within a top layer of the product, and wherein a second layer of the product does not contain polycrystalline diamond material.
21 . The laser lapping process of claim 12 , wherein the product includes one or more other forms of diamond or other super-hard materials, and is shaped as a plate or rod, wherein the plate is one of round or rectangular or wherein the rod is one of round or square, or in an irregular raw form.