JP3050656U - Screw tightening failure detection device using charge integrated value - Google Patents

Abstract

(57) [Summary] [PROBLEMS] When a screw is tightened with an electric screwdriver, a signal indicating whether the screw is good or not is obtained as a count signal. SOLUTION: The starting power is taken directly from an electric screwdriver,
The value obtained by integrating the electric charge is used as a signal for judging the quality of the screw, and is processed by the microcomputer board.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a combination with a screw tightening counter device for the purpose of preventing, for example, forgetting to tighten, screwing, double tightening and oblique tightening when tightening a screw with an electric screwdriver.

[0002]

[Prior art]

 Conventionally, a device has been developed that counts the number of times when a screw is tightened with an electric screwdriver (a device using a microswitch or the like as a sensor). If you forget to turn the screw, turn it off and tighten the screw again, or if you tighten it diagonally, the screw will bite before the screw is completely tightened halfway and a clutch signal will be output. This causes a serious defect in the counting device for the purpose of control.

[0003]

[Problems to be solved by the invention]

 As described in the prior art, when a screw is tightened with an electric screwdriver, it is simply counted by the clutch signal, so it is impossible to judge the quality of the tightened screw. Therefore, before the clutch signal is input, it is necessary to grasp the state of the screw by some means.

[0004]

[Means for Solving the Problems]

 As a result, the inventor devised a solution to the above problem. As a result, the starting charge of the electric driver was directly taken into the integration circuit (op-amp), and the integrated value charged to the capacitor was set by the volume. Means for sending a signal that has reached the integral setting amount to an 8-bit general-purpose microcomputer board (using a circuit that makes use of the characteristic of comparing the difference between inputs, which is a characteristic of operational amplifiers), and comparing it with the clutch signal inside the microcomputer board It is.

[0005]

[Embodiment]

 Hereinafter, an embodiment of the present invention will be described with reference to FIGS. Fig. 1 is an overall view of the present invention. Although the electric driver is originally connected directly to the electric driver power supply, in the present invention, an integration circuit (Fig. 2) is provided in the middle so that the starting charge of the electric driver can be directly taken in. Things.

When the electric driver shown in FIG. 2 is started, the reset relay (RY) is turned on, the contacts are separated, and the integration capacitor is charged through the integration setting variable volume resistor. When the gradually increased voltage (Fig. 3) reaches its peak, it is input from the output to the microcomputer board through the photocoupler.

[0007] As shown in FIG. 5, the integration set value is turned to the charge completion signal ON, and a standby state (A) is set. At this time, the quality of the screw is judged by the microcomputer board, and the input of the OFF signal of the electric driver voltage and the electric driver starting voltage is awaited.

That is, as shown in FIG. 4, even if a signal is output from the electric driver before the integral set value is turned ON, the signal is not counted.

The integration setting signal, the electric driver power OFF signal, the electric driver activation power OFF signal, and these three inputs are counted by the program processing in the microcomputer board.

[0010] The counted signal is sent to the display, and the result of comparison with the number set in advance is processed by the microcomputer board. If OK, the signal is output to the outside and the confirmation switch (foot switch) is turned ON. , Reset to the initial state.

If the confirmation switch is turned on before the count reaches the set number, an alarm buzzer and a red LED lamp call attention.

[0011]

[Effect of the invention]

 According to the present invention, as a result of directly taking in the electric charge as described in claim 1, even if the voltage of the electric driver supply changes, the rotation speed of the motor and the achievement of the integral value change proportionally, and the screw tightening quality judgment signal is output. Is very small and good results can be obtained.

As for the circuit configuration, the number of parts is small, the circuit can be incorporated without adjustment, and the circuit can be configured at low cost.

By processing the clutch input signal with the integral signal, it is a very excellent means against twice tightening, idling, oblique tightening, forgetting to tighten, and the like.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of the present invention.

FIG. 2 is an integration circuit used in the present invention.

FIG. 3 is a diagram showing a state where an integral value rises, a clutch signal input standby state, and a reset state.

FIG. 4 shows an electric driver power supply O before an integral value is turned on.
FIG. 5 is a diagram in which an FF signal, an electric driver activation power supply OFF signal, that is, a clutch signal is input.

FIG. 5 is a diagram illustrating a state where a clutch signal is input in a standby state in which an integral value is turned on.

[Explanation of symbols]

 RY Integral reset relay A Integral value OK Clutch input standby B Reset

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[Procedure amendment]

[Submission date] February 13, 1998

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims for utility model registration

[Correction method] Change

[Correction contents]

[Utility model registration claims]

Claims (1)

[Utility model registration claims] 1. A combination means in which a starting charge is directly taken into an integration circuit from an electric screwdriver, and a signal indicating whether screw tightening is good or not is taken into a counter device according to a set integration value.