JPH0360957A - Tracer head for non-contact type digitalizer - Google Patents

Abstract

PURPOSE:To reduce the size of a tracer head by a method wherein the image of single light is formed as a luminescent spot in at least two spots spaced away from each other on a model surface through the optical system of a projection part, and the luminescent spot image of reflection light at the luminescent spot is formed on a displacement detecting element by means of the optical system of a collecting light detecting part. CONSTITUTION:Light (laser beam) emitted from a single light source (semiconductor element) 12 forms luminescent spots at least at two spots (a) and (b), spaced away from each other, on a model surface by means of optical systems 13 and 14 of a projection part 8A. Reflection light at the luminescent spot is enlarged by optical systems 17 and 18 of light collecting detecting part 8B. The luminescent spot images are formed on respective displacement detecting elements (CCD image sensors) 19A and 19B, and a displacement amount of a luminescent spot image generated due to the protrusions and recessed parts of a model surface through relative movement of the tracer head or a model is simultaneously outputted. Based on output data, the shape of the model surface and a speed vector are calculated.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a tracer head for a digitizer that digitizes a model shape and creates an NC program.

Conventional technology A tracer head for a non-contact digitizer that can calculate the model shape and velocity vector detects changes in the bright spot irradiated on the model surface with high precision, and the distance of the tracer head from the model surface is always constant. This method continuously detects the coordinate values of the model surface by tracing it while maintaining the coordinates of the model. At this time, it is necessary to calculate a velocity vector in order to automatically move the tracer head or model along the axis, and for this purpose, it is necessary to simultaneously detect changes in two bright spots on the model surface that are parallel to the direction of movement and separated by a certain distance. There is a need to. conventionally,
In order to detect changes in the bright spots at these two locations, sensors of the same type were placed side by side, and displacement was detected simultaneously by each sensor.

Problems to be Solved by the Invention The method of arranging sensors of the same type in parallel as described in the prior art has the problem that the entire tracer head becomes large, the working area as a digitizer becomes narrow, and the operability deteriorates. was.

The present invention has been made in view of the above-mentioned problems of the conventional technology, and its purpose is to reduce the size,
The present invention aims to provide a lightweight tracer head for a non-contact digitizer.

Means for Solving the Problems In order to achieve the above object, the tracer head for a non-contact digitizer according to the present invention has a V-shape in which the light emitting part and the light receiving detection part have a predetermined angle in a plane perpendicular to the scanning direction. In the optical tracer head disposed in the model, the light projecting section is constituted by an optical system that focuses one light beam on at least two distant points on the surface of the model as bright spots.

Further, in an optical tracer head in which a light emitting section and a light receiving detecting section are arranged in a V-shape at a predetermined angle in a plane perpendicular to the scanning direction, the light receiving detecting section is arranged at at least two distant points on the model surface. It includes one optical system that forms two bright spot images of a bright spot, and a displacement detection element that simultaneously outputs the displacement amount of each of the bright spot images.

In addition, in an optical tracer head in which a light emitter and a light receiving detector are arranged in a V-shape at a predetermined angle in a plane perpendicular to the scanning direction, one light is directed to at least two distant points on the model surface. an optical system that forms an image as a bright spot;
The apparatus includes one optical system that forms a bright spot image of the bright spot, and a displacement detection element that simultaneously outputs the amount of displacement of the bright spot image.

Effect: The light emitted from one light source forms bright spots at at least two separate locations on the model surface by the optical system of the light projector. The reflected light from this bright spot is magnified by the optical system of the light receiving and detecting unit, and a bright spot image is formed on each displacement detection element. outputs the amount of displacement at the same time.

Then, based on this output data, the shape and velocity vector of the model surface are calculated.

Embodiments In a well-known digitizer, a table 3 on which a model 2 is attached is moved on a guide surface in the X-axis direction carved in a bed 1. A rectangular column 4 is erected on both sides of the bed 1. Y of crossbeam 5 installed on column 4
The main spindle if6 is movably placed on the axial guide surface, and a tracer quiller is provided on the main spindle head 6 so as to be movable in the Z-axis direction. A tracer head 8 is removably attached.

As shown in FIG. 3, the tracer head 8 has a light emitting section 8A and a light receiving detecting section 8B arranged in a V-shape at a predetermined angle θ in a plane perpendicular to the scanning direction. A semiconductor element 12 that emits laser light is mounted on the light projecting tube 11 of the light projecting section 8A, and in the center of the light projecting tube,
A convex lens 13 is included to convert the diffused laser light into parallel light. Furthermore, two convex lenses 14A, 14 whose optical axes are slightly apart from each other with respect to parallel light are provided at the lower end of the light projection tube.
A combination lens 14 consisting of B is attached. Convex lens 14A of this combination lens 14.

The distance between the optical axes 14B is accurately maintained at, for example, a distance of 2 mm for vector calculation, and they are separated in the scanning direction, and the light source by the semiconductor element 12 is placed on the model surface at two locations a, 211 apart in the scanning direction. It is designed to form an image as a bright spot on b.

On the other hand, inside the lens barrel 16 of the light receiving and detecting section 8B, the reflected light from the two bright spots a and b on the model surface is captured, and two bright spot images are displayed at an appropriate magnification on the element of a one-dimensional COD image sensor, which will be described later. An objective lens 17 and a magnifying lens 18 are provided to connect the two. The CCD image sensors 19A and 19B are installed in parallel at positions corresponding to the two bright spot images on the lens barrel 16, and are aligned in the direction of the COD element array in the moving direction of the bright spot images that move in response to changes in the model surface. The reading circuit of the COD image sensor detects and outputs the movement of the bright spot image. Further, a digitizer control word N20 is installed near the bed 1 to create NC data based on output data from the CCD image sensors 19A and 19B.

Next, the operation of this embodiment will be explained. When a voltage is applied to the semiconductor laser element and a laser beam is emitted, the diffused laser beam is converted into parallel light by a convex lens 13, and then illuminated by a combination lens 14 at positions a and b on the surface of the model 2. Image a point. The reflected light from this bright spot is captured by the objective lens 17 of the light receiving and detecting section 8B, and formed into an image on the front surface of the magnifying lens 18, which further magnifies it and projects it onto the element of the one-dimensional CCD image sensor 19A. The bright spot image at position a is captured by the COD image sensor 19B.
A bright spot image at position b is formed on the element. The bright image on the COD element is displaced due to the unevenness of the model surface caused by the relative movement of the CCD element of the model 2 or the tracer head 8. This amount of displacement is detected by the reading circuit of the COD image sensor and output to the digitizer control device 20, and the Z-axis movement of the quillure is controlled so that the distance from the bright spot on the model surface to the tracer head 8 is always constant. The coordinate value of the model surface is calculated from the current value of the Z axis, the slope angle is calculated from the deviation value of the data of the CCD image sensors 19A and 19B measured at the same time, and the velocity vector is calculated and the feed axis The speed is determined and NC data is created.

Effects of the Invention Since the present invention is configured as described above, it produces the following effects.

The optical system of the light projector focuses one light beam on at least two separate locations on the surface of the model as bright spots, and the optical system of the light receiver detects the reflected light of the bright spots on the displacement detection element. Since the image is formed and the displacement amount of the bright spot image is simultaneously output, there is no need to install tray heads of the same type in parallel, and the tracer head can be made smaller and lighter.

[Brief explanation of drawings]

Fig. 1 is a sectional view for explaining the light emitting part of the tracer head, Fig. 2 is a sectional view for explaining the light receiving and detecting part of the tracer head, and Fig. 3 is a perspective view of the light emitting part and the light receiving detecting part arranged in a V shape. , FIG. 4 shows the gap between the digitizer bags. 8A...Light projection part 8B...Light receiving detection part 13...Convex lens 14...Combination lens 17...Objective lens 18
・・Magnifying lenses 19A, 19B・・CCD image sensor 1

Claims (3)

[Claims] (1) The light emitter (
In an optical tracer head (8) in which a light reception detection section (8A) and a light receiving detection section (8B) are arranged in a V-shape at a predetermined angle (θ), the light projecting section transmits one light onto the surface of the model (2). A tracer head for a non-contact digitizer, comprising an optical system (13, 14) that forms an image as a bright spot on at least two distant points (a, b) on the top. (2) The light emitter (
In an optical tracer head (8) in which a light receiving detector (8A) and a light receiving detector (8B) are arranged in a V-shape with a predetermined angle (θ), the light receiving detector is located at least on the surface of the model (2). One optical system (17, 18) that forms two bright spot images of two bright spots (a, b), and a displacement detection element (17, 18) that simultaneously outputs the displacement amount of each of the bright spot images. 19A, 1
9B) A non-contact tracer head comprising: (3) The light emitter (
In the optical tracer head (8), in which the light reception detection section (8A) and the light receiving detection section (8B) are arranged in a V-shape at a predetermined angle (θ), one light beam is transmitted to at least one remote point on the surface of the model (2). An optical system (13,
14), one optical system (17, 18) that forms a bright spot image of the bright spot, and a displacement detection element (19A, 19B) that simultaneously outputs the displacement amount of the bright spot image. A non-contact tracer head that is characterized by: