JPH03251366A - Dressing timing detector for grinding wheel - Google Patents

Abstract

PURPOSE:To surely detect the dressing timing of a grinding wheel and prevent the erroneous operation accompanied with the change of the working condition by installing a comparison part which compares the standard consumed electric power and the consumed electric power in grinding work and outputs a dressing signal when the ratio becomes over a certain value and an anomaly signal does not exist. CONSTITUTION:When grinding work starts, the consumed electric power of a motor 4 is detected by an electric power detection part 5. In a comparison part 7, the standard consumed electric power supplied from a setting part 6 and the actual consumed electric power are compared, and the clogging state of a grinding wheel is checked. While, if the working condition changes, an anomaly detection part 3 detects the anomaly, and outputs an anomaly signal. If clogging develops to the degree where the grinding wheel requires dressing, the ratio between the both of the electric power becomes over a certain value, and the comparison part 7 outputs a dressing signal. However, even if the ratio becomes over a certain value, if an anomaly signal is outputted, the comparison part 7 does not output the dressing signal, since the anomaly is generated because of the change of the working condition.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a dressing timing detection device for a grinding wheel in a grinding machine.

(Conventional technology) In a grinding machine that performs grinding by rotating a grinding wheel at high speed,
If the grinding wheel becomes clogged, problems such as grinding will occur.

Therefore, during grinding work, it is necessary to constantly check the clogging condition of the grinding wheel, and if clogging occurs, the grinding wheel must be immediately dressed.

Therefore, conventionally, a method has been adopted in which an operator determines the clogging state of the grinding wheel based on the grinding sound or the like.

(Problem to be Solved by the Invention) Conventionally, as mentioned above, the worker judged the clogging state of the grinding wheel based on the grinding sound, etc., so the worker was required to be skilled in grinding work, and There is a problem in that even a person skilled in the art would have difficulty distinguishing abnormal sounds from abnormal sounds caused by changes in processing conditions. As a result, machining defects such as grinding and burning sometimes occur, and work efficiency decreases due to errors in handling abnormalities.

In view of such conventional problems, the present invention provides a dressing time detection device for a grinding wheel that can reliably detect clogging of the grinding wheel with a simple configuration and prevent malfunctions due to changes in processing conditions.

(Means for Solving the Problems) The present invention includes a setting section 6 that sets standard power consumption according to processing conditions, and a power detection section 5 that detects the power consumption of the grinding wheel drive motor 4 during grinding. , an abnormality detection unit 3 that detects a change in machining conditions and outputs an abnormal signal, compares the standard power consumption and the power consumption during grinding, and outputs a dressing signal when the ratio is above a certain level and there is no abnormal signal. It is equipped with a comparing section 7 which outputs the following.

(Function) When the grinding process is started, the power detection unit 5 detects the power consumption of the motor 4. Then, the comparing section 7 compares the standard power consumption from the setting section 6 with the actual power consumption, and checks the clogging state of the grinding wheel.

On the other hand, if there is a change in the machining conditions, the abnormality detection section 3 detects it and outputs an abnormality signal. If the grinding wheel becomes clogged to the extent that dressing is required, the ratio of both electric powers becomes a certain value or more, so the comparator 7 outputs a dressing signal. However, even if the ratio exceeds a certain level, if there is an abnormal signal at that time, it is due to a change in processing conditions.
The comparator 7 does not output a dressing signal.

(Example) Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

In the figure, reference numeral 1 indicates a rotation detecting section such as a tachometer that detects the feed rate of the grinding wheel, and 2 indicates a displacement detecting section such as a displacement meter that detects the actual depth of cut during grinding.

Reference numeral 3 denotes an abnormality detection section which outputs an abnormality signal when either or both of the feed rate and the depth of cut change by a certain amount or more due to a change in the grinding conditions. 4 is a grinding wheel drive motor that drives the grinding wheel via a grinding wheel shaft, and 5 is a power detection unit such as a wattmeter that detects the power consumption of the motor 4 during grinding. Reference numeral 6 denotes a setting section, which sets the standard power consumption of the motor 4 during grinding according to the workpiece, the type of grinding wheel, and other processing conditions. 7 is the comparison section,
The standard power consumption set by the setting unit 6 and the actual power consumption during grinding detected by the power detection unit 5 are compared, and when the latter exceeds the former and the ratio is above a certain level, the abnormality detection unit If the ratio continues for a predetermined time or longer when there is no abnormal signal from No. 3, it is determined that the grinding wheel is clogged, and a dressing signal is output. 8 is a dressing time display section, 9 is a dressing time alarm section, and these are the comparison section 7.
It is activated by the dressing signal from.

Next, the operation will be explained. When performing the grinding process, first, the standard power consumption according to the processing conditions is set by the setting section 6, and then the process is started.

When machining is started, the rotation detection section 1 detects the feed rate, the displacement detection section 2 detects the depth of cut, and the power detection section 5 detects the power consumption. Then, if the feed rate and/or the depth of cut change by a certain amount or more due to a change in machining conditions, the abnormality detection section 3 outputs an abnormality signal. On the other hand, a comparison section 7 compares the power consumption from the power detection section 5 and the standard power consumption from the setting section 6 to check the clogging state of the grinding wheel. That is,
If the grinding wheel becomes clogged, the power consumption of the motor 4 increases accordingly, so by comparing the power consumption with the standard power consumption, the clogging state of the grinding wheel can be determined. If the power consumption exceeds the standard power consumption and the ratio is above a certain level, and there is no abnormal signal at that time, the comparison unit 7 outputs a dressing signal when the power consumption continues for a predetermined time or more, and the dressing time display unit 8, The dressing time alarm section 9 operates to display and warn that the grinding wheel is in the dressing time. When there is an abnormal signal, even if the power consumption increases, it is due to a change in the machining conditions and there is a cause other than the clogging of the grinding wheel.
The comparator 7 does not output a dressing signal. Therefore, malfunctions due to changes in processing conditions can be prevented, and clogging of the grinding wheel can be detected with high accuracy. Further, even if the ratio is equal to or higher than a certain value, if the ratio does not continue for a predetermined period of time or more, the comparator 7 does not output a dressing signal because it is due to noise.

Note that the signal processing may be performed by hardware or by software using a microcomputer or the like. Further, the feed rate and depth of cut may be detected by other methods.

(Effects of the Invention) According to the present invention, the setting section 6 sets the standard power consumption according to the processing conditions, the power detection section 5 detects the power consumption of the grinding wheel drive motor 4 during grinding, and the processing An abnormality detection unit 3 that detects a change in conditions and outputs an abnormal signal, compares the standard power consumption and the power consumption during grinding, and outputs a dressing signal when the ratio is above a certain level and there is no abnormal signal. Since the comparison unit 7 is provided, the dressing time of the grinding wheel can be reliably detected with a simple configuration, and malfunctions due to changes in processing conditions can be prevented, and detection accuracy is improved.

[Brief explanation of drawings]

The drawing is a block diagram showing one embodiment of the present invention. 3-abnormality detection section, 4.-low stone wheel drive motor, 5 power detection section, 6-setting section, 7-comparison section.

Claims (1)

[Claims] (1) A setting section (6) that sets the standard power consumption according to the machining conditions, a power detection section (5) that detects the power consumption of the grinding wheel drive motor (4) during grinding, and An abnormality detection section (3) that detects a change and outputs an abnormal signal compares the standard power consumption with the power consumption during grinding, and outputs a dressing signal when the ratio is above a certain level and there is no abnormal signal. A dressing time detection device for a grinding wheel, characterized by comprising a comparing section 7.