Electric screwdriver with screw locking detecting function

Abstract

The invention provides an electric screwdriver with a screw locking detecting function. The electric screwdriver comprises a screwdriver driving module, an operation detecting unit, a halting detecting unit, a control unit and an alarm unit. The screwdriver driving module is provided with a tool head, the operation detecting unit is connected with the screwdriver driving module, operation signals can be continuously outputted when the screwdriver driving module is operated, the control unit is connected with the operation detecting unit and the alarm module, and a first warning signal can be outputted to the alarm module when a computed operation signal starting and finishing duration is shorter than a lower limit of locking time. The electric screwdriver has the advantages that the electric screwdriver can know that the tool head stops rotating by the aid of interruption of the operation signals even if the electric screwdriver is braked not because of a clutch, so that screw unlocking phenomena not because of clutch braking can be detected, and negligence of users can be prevented.

Description

technical field [0001] The invention relates to an electric screwdriver, in particular to an electric screwdriver capable of detecting screw locking, detecting whether the screw is floating or slipping, and sending out a warning signal. Background technique [0002] The existing electric screwdrivers mainly use the electric motor in the sub-drive module to drive a tool head to rotate (such as a screwdriver, etc.), so that the user can use the tool head to lock screws, nuts and other components, and the earliest electric screwdriver In order to prevent the tool head from continuing to rotate after the screw is tightened, causing the internal circuit to burn out, a clutch unit is installed in the driver module of the screwdriver. The clutch unit can detect that the tool head has locked the screw (that is, the tool head rotates). The resistance is too large), and when it is detected that the tool head has locked the screw, it will automatically perform the braking action to sto...

AI Technical Summary

Problems solved by technology

[0008] Generally, when a thread slips or a floating lock occurs on a screw, usually because the thread of the screw and the thread of the screw hole are not aligned, the two are stuck before the screw is tightened. Therefore, the clutch unit 72 in the screwdriver drive module 70 will lock The action of disengaging the tool head 73 from the electric motor 71 is performed before the lower limit of time is attached. Once the above-mentioned electric screwdriver detects that the driver drive module 70 is started, the clutch unit 72 quickly disengages the tool head 73 from the electric motor 71 (the time is shorter than the lower limit of the locking time). , it means that the screw is slipping; however, if the thread is not stuck due to misalignment, but the user has stopped the electric screwdriver before the screw is tightened (for example, the finger loosens the start button, etc.), at this time, The screw is still in the floating lock state, but because the tool head 73 in the screwdriver drive module 70 is not in the state of tightening the external screw, the stop detection unit 80 does not output a stop signal, so that the control unit 90 cannot confirm that the screwdriver drive module 70 has started running Until the time when the control unit 90 receives the stop signal, the warning signal will not be output, and the warning module will not perform the warning action. This kind of floating lock situation will be ignored by the user. Therefore, the above-mentioned electric screwdriver still needs to be improved.

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