JP3016502B2 - Surface roughness measuring device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring the surface roughness of a surface of an object by a contact-type optical measuring device. 2. Description of the Related Art As a method for measuring the surface roughness of an object, a measuring instrument such as a scale or a caliper is used for a surface having relatively large unevenness, and a micrograph is used for a minute unevenness. Techniques for measuring by using such methods are known. Further, in the case of a surface located in the middle of them, a technique of using a device for measuring a minute distance such as a laser range finder to grasp irregularities by a change in distance from a fixed position is also used. [0003] However, in the prior art, the detection is performed by human judgment, or by image processing or distance measurement by a camera. It is difficult to perform stable measurements due to problems such as the influence of external light and the like, and when measuring surface roughness in a wide range, it takes time to move humans and equipment, and it takes time and labor. Met. In particular, in the conventional method using a laser range finder or the like, it is necessary to always maintain a constant positional relationship with the object to be measured, and the irregular reflection on the surface of the object to be measured measures the time of receiving the reflected light of the laser. , Which is a factor of measurement error. Accordingly, the present invention has been made in view of the above problems, and provides a highly accurate surface roughness measuring device which can easily maintain a constant detection space, is resistant to disturbances such as the influence of external light, and the like. The purpose is to do. According to the present invention, light is projected from a light emitting section having a light emitting element onto a surface of an object to be measured by bringing the element into close contact with the surface of the object to be measured. In a surface roughness measuring device for receiving reflected light from the surface of the object by a light receiving unit and detecting the roughness of a corresponding surface of the measured object by a signal output corresponding to a change in the amount of light received from the light receiving unit, A V-shaped groove is provided on the measurement surface to be in close contact with the surface of the measurement body, and a main body is provided.
The bottom of the U-shaped groove is parallel to the measurement surface, and a light receiving portion having a plurality of light receiving elements arranged linearly is attached to the bottom, and a plurality of light receiving portions arranged linearly on the inclined surface of the groove. The light-emitting part having the light-emitting element is mounted. DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention is constructed as described above, and the contact measuring surface of the optical measuring device is brought into close contact with the surface of the measuring object whose surface roughness is to be measured. The light is projected onto the surface of the measured object, the light reflected from the surface of the measured point of the measured object is received by the light receiving element of the light receiving section, and a signal is output according to a change in the amount of received light. Further, since this measuring device has a linear light emitting unit and a lecture attending unit and can have linear measuring points, it is possible to measure at multiple points at the same time. [0008] Therefore, when the measurement results of these multiple points are displayed side by side with adjacent measurement points, the surface roughness is displayed. Since the measuring surface of the measuring device is in close contact with the object to be measured, it is possible to prevent the influence of external light from entering, and to prevent the relative positions of the measuring points from shifting, so that highly accurate measurement can be performed. It becomes possible and the operation is simple. Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing an example of a contact-type optical measuring device used in a surface roughness measuring method according to the present invention. A V-shaped groove 2 is provided on a measuring surface 7 which is a contact surface on a main body 1. A light receiving portion 4 having a plurality of light receiving elements 4a arranged linearly is attached to a bottom 3 of the V-shaped groove 2 parallel to the measurement surface 7, and a linear surface is provided on the inclined surface 5 of the groove 2. The light-emitting unit 6 having a plurality of light-emitting elements 6a arranged at the same position is attached. FIG. 2 shows a cross section taken along the line AA in FIG. 1, and reference symbol P indicates a measurement point P on the measurement surface 7. The projection light projected from the light emitting section 6 is reflected at the measurement point P, and the light receiving section is arranged at a position where the measurement point P is selectively viewed, and receives the reflected light at the measurement point P. . When the light receiving element 6a receives the light, it outputs a signal in accordance with a change in the amount of received light. Hereinafter, a method for measuring the surface roughness by the above-mentioned contact type optical measuring device will be described with reference to FIGS. FIG. 3 shows a state in which the main body 1 of the measuring device is brought into close contact with the measuring surface of the measured object 11, and the measuring surface is composed of a rough surface portion 11a and a less rough portion 11b. . FIG. 4 shows a cross section of FIG. 3, and FIG. 5 is a partially enlarged view of a rough portion 11a. At this time, the surface 11 of the object 11
In a (for example, section AA), the projection light from the light emitting unit 6 is irregularly reflected on the surface of the measured object, and the reflected light is detected by the light receiving unit 4, but most of the projected light is diffused by diffuse reflection, The change in the amount of light received by the light receiving section 4 is large (FIG. 6), and the area immediately next to it changes as shown in FIG. Next, the portion 1 of the measured object 11 having a small roughness
In 1b (section BB), the projection light from the light emitting unit 6 is reflected on the surface of the measured object without being diffused so much, the change in the amount of light received by the light receiving unit 4 is small (FIG. 8), and is immediately adjacent thereto. Is slightly changed as shown in FIG. Since such detection patterns are sequentially combined over a linear measurement point (measurement line) composed of the light emitting section 6 and the light receiving section 4 of the main body 1, the detection output from the measuring apparatus is shown in FIG. become that way. That is, when the light receiving element 4a of the light receiving unit 4 corresponding to a in FIG. 4 is set as the first element and the following numbers are assigned in ascending order, the detection output of the student element corresponding to b and c in FIG. The difference between c) and c) corresponds to the concavo-convex interval in FIG. Therefore, 1 corresponding to a in FIG.
By taking the difference between the detection outputs of the next element in order from the element No., it is possible to determine the size of the unevenness. Also, for example, FIG.
The variation in the detection output between a and d in FIG.
To d section can be represented. Similarly,
Variations in the detection output from d to e in FIG. 6 are the surface roughness in the portions d to e with little unevenness in FIG. As described above, the surface roughness can be easily measured by arranging the main body 1 of the measuring device at the portion to be measured. Further, since the detection is performed in the measurement space formed by the groove defined by the measuring device main body 1 which is in close contact with the surface of the object to be measured, the positional relationship with the object to be measured is different from the conventional method using a laser distance meter. It is not necessary to measure with particular awareness. Furthermore, the measuring device according to the present invention utilizes the irregular reflection on the surface of the object to be measured, which has been a problem with the conventional technology such as a laser range finder, so that stable measurement is possible and high accuracy. The present invention has the following advantages because it is configured as described above. (1) Since the detection is performed within a fixed measurement space provided in the measurement device, the operation is simple, stable and highly accurate. (2) Since the measuring device is in close contact with the measured object, the influence of disturbance such as external light is small. (3) Therefore, accurate and accurate surface roughness can be measured.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a contact-type optical measurement device used in one embodiment of the present invention. FIG. 2 is a sectional view taken along line AA of FIG. FIG. 3 is a perspective view showing a mode in which measurement is performed by the measurement device in FIG. 1; FIG. 4 is a longitudinal sectional view of FIG. 3; FIG. 5 is an enlarged view of a portion D in FIG. 4; FIG. 6 is a sectional view taken along line BB of FIG. 4; FIG. 7 is a cross-sectional view of a portion adjacent to the BB cross section in FIG. 4; FIG. 8 is a sectional view taken along line CC of FIG. 4; FIG. 9 is a cross-sectional view of a portion adjacent to a cross section taken along line CC of FIG. 4; FIG. 10 is a diagram showing an example of a detection output indicating surface roughness. [Description of Signs] 1 ... Main body 2 ... Groove 3 ... Bottom 4 ... Light receiving unit 5 ... Inclination unit 6 ... Light emitting unit 7 ... Adhesion measuring unit 11 ... Measured object

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-60-135810 (JP, A) JP-A-63-61111 (JP, A) JP-A-54-110865 (JP, A) JP-A-62 69112 (JP, A) JP-A-3-202705 (JP, A) JP-A-2-32206 (JP, A) JP-A-63-206604 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01B 11/00-11/30 102 G01N 21/84-21/91 G06T 1/00-7/00

Claims (1)

(57) [Claims] A light-emitting unit having a light-emitting element, which is in close contact with a surface of a measured object, projects light projected from the light-emitting unit on the surface of the measured object, and receives light reflected from the surface of the measured object. In a surface roughness measuring device that detects the roughness of a corresponding surface of a measured object by a signal output corresponding to a change in the amount of received light from a light receiving unit, a measuring surface to be brought into close contact with the surface of the measured object The body is provided with a V-shaped groove,
The bottom of the V-shaped groove is parallel to the measurement surface, and a light receiving section having a plurality of light receiving elements arranged linearly is attached to the bottom, and the light receiving section is linearly arranged on the inclined surface of the groove. A light emitting section having a plurality of light emitting elements is attached.