JP3204973U - Electric rotary tool with screw tightening state judgment function - Google Patents

Abstract

[PROBLEMS] To set a target value of a screw tightening state for determining an appropriate screw tightening state and various unsuitable screw tightening states in screw tightening operations, which can be performed with a simple operation. An electric rotary tool having a screw tightening state determination function is provided. A driver bit 20 is coupled to a drive output shaft of an electric motor 12 via a clutch mechanism 18, and a rotation amount detecting means 24 for detecting a screw tightening rotation amount based on the rotation of the driver bit 20 is provided. A target rotation amount for screw tightening is automatically set by a plurality of screw tightening operations, and an appropriate screw tightening state can be determined in subsequent screw tightening operations. [Selection] Figure 1

Description

  The present invention relates to an electric rotating tool configured to perform screw tightening work by connecting a driver bit to a drive output shaft of an electric motor via a clutch mechanism, and in an appropriate screw tightening state and various inappropriateness It is related with the electric rotary tool provided with the screwing state determination function which can be set so that it can confirm and determine easily and reliably about the screwing state which becomes.

  Conventionally, as a screw tightening device that performs screw tightening work by rotationally driving a driver bit by a driving means such as an electric motor, etc., it has various functions that can achieve screw tightening work properly and smoothly and quickly. Screw fastening devices have been proposed and put into practical use.

  For example, in an electric screwdriver configured to couple a screwdriver bit to a drive output shaft of an electric motor via a clutch mechanism and perform a screw tightening operation, screw tightening is performed with respect to a screw hole provided in a required screw mounting object. When the screw is tightened by the device, the predetermined screw tightening torque value is reached in a state where the screw is not completely screwed, and the clutch mechanism is operated to complete the screw tightening operation. is there.

  First, the applicant of the present invention can detect a screw tightening failure such as a screw galling or screw floating in a screw hole easily and simply with a relatively simple configuration at a low cost in an appropriate and reliable manner. A fastening device was developed and a patent application was filed (see Patent Document 1).

  That is, the screw tightening device described in Patent Document 1 performs a screw tightening operation by rotationally driving a rotary tool such as a driver bit by a driving means such as an electric motor, and completes tightening of a screw to a required screw mounting target. In the screw tightening device configured to detect the load torque generated in the rotary tool and to stop the rotation drive of the rotary tool when the load torque reaches a preset torque value, (1) A rotation amount detection means is provided in the rotary tool or the drive means to detect a rotation amount based on the number of rotations and rotation time associated with the rotation drive of the rotary tool, and (2) a screw head is provided at the tip of the rotary tool. When the tip of the screw shaft of the screw fitted with the portion is positioned and brought into contact with the screw hole of the screw mounting target, the screw tightening reference point ( 1) the is obtained by adapted to set by screwing the reference point setting means.

  (3) After the screw tightening reference time is set by the screw tightening reference time setting means, the driving means of the rotary tool is started and the screw tightening start time (t2) is set by the screw tightening start time setting means. (4) A screw tightening completion time (t3) when a load torque generated in the rotary tool reaches a preset torque value by rotating the screw positioned and abutting on the screw hole by the rotational drive of the rotary tool. ) Is detected by the screw tightening completion time detection means, and (5) after setting the screw tightening reference time (t1) by the screw tightening reference time setting means, the screw tightening start time setting means starts the driving means of the rotary tool. From the screw tightening start time (t2) to be detected to the screw tightening completion time (t3) detected by the screw tightening completion time detecting means, the rotation amount detecting means detects Rotation of the rolling tool, is obtained by constituting the quality of screw tightening by determining whether compared with a preset reference value is within the allowable range to determine the screwing quality determining means.

  Further, in the screw tightening device described in Patent Document 1, a torque setting clutch mechanism provided at the shaft coupling portion between the drive shaft of the drive means that rotates the rotary tool and the rotary tool is used as the screw tightening completion time detection means. , Using a load current detecting means for detecting a load current of an electric motor that rotationally drives the rotary tool, or a detection signal for detecting a screw tightening completion time when the clutch is operated when reaching a preset torque setting value. It is disclosed that a screw tightening completion point detection signal when reaching a load current value is obtained.

JP 2010-214564 A

  As described above, in the screw tightening device described in Patent Document 1, the screw tightening reference time (t1) is set, and the rotation amount is detected from the screw tightening start time (t2) to the screw tightening completion time (t3). It is judged whether the amount of rotation of the rotating tool detected by the means is within the allowable range compared with the preset reference value, and screw tightening failure such as screw galling or screw floating in the screw hole Can be detected appropriately and reliably at a low cost by a simple and simple and relatively simple configuration.

  However, in the screw tightening device, in each screw tightening operation, the screw tightening reference time (t1) is set, and from the screw tightening start time (t2) to the screw tightening complete time (t3), the rotation amount detecting means Since the detected amount of rotation of the rotating tool is detected, it is necessary to always pay attention to the work of setting the screw tightening reference time point (t1), and there is no particular problem for skilled workers, but unskilled workers In the screw tightening work in step 1, there may be a case where the proper work effect and work efficiency exhibited in the invention cannot be obtained.

  Therefore, the inventor of the present invention, in the electric driver employing the above-described variously proposed clutch mechanisms, detects the amount of rotation of the electric motor with respect to the control circuit of the electric motor that rotates the driver bit. Means for detecting and recording the amount of rotation of the electric motor in the screw tightening operation, detecting the completion of screw tightening by the clutch operation of the clutch mechanism, and We paid attention to the construction of an electric driver provided with a control unit for sequentially detecting or recording the rotation amount from the start of the screw tightening of the motor.

  In other words, in the present invention, when the predetermined screw tightening operation is started using the electric screwdriver having the above-described configuration, first, a plurality of preliminary screw tightening operations are performed, and the rotation is started from the start of each screw tightening. The detection of the amount of rotation of the electric motor is started by the amount detection means, and then the completion of screw tightening is detected by the clutch operation of the clutch mechanism, and the rotation of the electric motor from the start of screw tightening at the time of the clutch operation is detected. Each amount is detected and recorded, and the target rotation amount is automatically set based on the detected and recorded rotation amount on condition that all of the detected and recorded screw tightening rotation amount states are all appropriate. Then, in a predetermined screw tightening operation thereafter, the rotation amount of the electric motor from the start of the screw tightening operation to the clutch operation time of the clutch mechanism is sequentially detected, and the clutch operation time It was found that the appropriateness of the screw tightening state can be properly determined by comparing the detected rotation amount with the target rotation amount.

  In the present invention, when the preliminary screw tightening operation is performed a plurality of times for the first time, the clutch mechanism is preliminarily subjected to standard torque adjustment, and the target set thereafter is set. Based on the rotation amount (including the allowable range), the screw tightening state is determined for each screw tightening rotation amount detected in the predetermined screw tightening operation, so that the target rotation amount (including the allowable range) is satisfied. Therefore, it can be easily and reliably determined that the screw is properly tightened.

  Further, in the present invention, based on the stationary torque set for the electric motor, the rotation stop of the electric motor reaches the stationary torque when the screw tightening is completed, and the rotation is stopped. Therefore, instead of detecting the clutch operation time by the clutch mechanism, it is also possible to detect the rotation stop time based on the stopping torque of the electric motor, and to It is also possible to appropriately detect the amount of rotation of the electric motor accompanying the completion of tightening.

  In addition, with respect to the target rotation amount set in advance as described above, each of the electric motors sequentially detected by the predetermined screw tightening operation until the clutch operation time or the rotation stop time based on the stop torque of the electric motor. When comparing the rotation amount, the rotation amount of the electric motor detected from the set value of the target rotation amount to the clutch operation time or the electric motor rotation stop time in a predetermined screw tightening operation is sequentially added or subtracted. The final rotation amount detection value can be compared with the set value of the target rotation amount (including the allowable range).

  In the present invention, in the electric rotary tool having the above-described configuration, load current detection means is provided so that the load current value proportional to the screw tightening torque value is detected and recorded at the same timing as the screw tightening rotation amount. Along with the rotation amount detection means for detecting and recording the rotation amount of the electric motor, the rotation amount of the electric motor and the load current value are detected and compared with a preset target rotation amount (including an allowable range). It is set to display the determination result by comparing the pre-set target load current value (including the allowable range) to determine whether the screw tightening state is good or not, and detecting the load current value during clutch operation. can do.

  Further, in the present invention, in the electric rotary tool, an operation switch or an encoder that is operated when the driver bit is in contact with an object to be screwed, or a push operation switch that is operated by an axial displacement at the time of the contact. By providing and detecting the operation signal, it can be set as the screw tightening start time when the screw tightening operation is performed.

  In this way, setting the screw tightening start time when performing the screw tightening operation is performed when detecting and recording the rotation amount of the electric motor detected by the rotation amount detection means in the screw tightening operation by the electric screwdriver. At the same time that the drive switch for driving the electric motor is operated by the switch operating member, the rotation amount of the electric motor is detected by the rotation amount detecting means. As a result, for example, when the driver bit is idled until it abuts against the object to be screwed, the rotation amount detected at the idle rotation timing is the electric amount during the actual screw tightening operation. Since the rotation amount of the motor is inaccurate, it is possible to accurately detect the rotation amount of the electric motor during the actual screw tightening operation by setting the screw tightening start time as described above. It becomes.

  In particular, by detecting the operation signal of the push operation switch as described above, the screw tightening start time when the screw tightening operation is performed when the screwdriver bit is first brought into contact with the screw mounting target is set. Then, by operating a drive switch for driving the electric motor, it is possible to accurately detect the rotation amount of the electric motor during the actual screw tightening operation until the screw is seated.

  Therefore, according to the present invention, as seen in a micrometer, in precision screws, along with the improvement of the processing accuracy related to the pitch dimension of the screw, in conjunction with the improvement of the detection accuracy of the amount of rotation of the screw described above, The positioning of the screw rotation amount and the screw shaft movement distance can be set with high accuracy, so that when the screw is tightened, the screw is properly seated with respect to its mounting object. The relationship of the rotation amount can be set and confirmed accurately, and the reliability of the quality determination in the screw tightening operation can be sufficiently enhanced.

  Accordingly, an object of the present invention is to simply and surely confirm and determine in an electric rotary tool configured to couple a driver bit to a drive output shaft of an electric motor via a clutch mechanism and perform a screw tightening operation. An object of the present invention is to provide an electric rotary tool having a screw tightening state determination function that can be set so that

In order to achieve the above object, an electric rotary tool having a screw tightening state determining function according to claim 1 of the present invention includes an electric motor, a drive switch for driving the electric motor, and driving of the electric motor. A driver bit coupled to the output shaft via a speed reduction mechanism and a clutch mechanism, a switch operation member for operating the drive switch, a clutch operation detection sensor for detecting a clutch operation of the clutch mechanism, and an electric motor An electric motor control circuit that performs drive and stop control, and a rotation amount detection means that detects a rotation amount of the electric motor, each of which includes an electric rotary tool,
A screw tightening start time memory for detecting and recording a screw tightening start time when screw tightening is performed by an operation signal of the operation switch or encoder, provided with a drive switch or an encoder that operates when the screw of the screwdriver bit is in contact with an object to be mounted. Means,
The rotation amount detecting means detects the rotation amount of the electric motor relative to the rotation of the driver bit from the start time of the screw tightening to the clutch operation time due to the completion of the screw tightening by the screw tightening operation by the first plural times. A rotation amount storage means for recording the detected rotation amount and setting a target rotation amount (including an allowable range) on condition that the plurality of screw tightening states are all appropriate;
In the subsequent screw tightening operation, the rotation amount detection means sequentially detects the rotation amount of the electric motor relative to the rotation of the driver bit from the screw tightening start time to the clutch operation time by the clutch mechanism when the screw tightening is completed. Control means for controlling the screw tightening state to be judged by recording the rotation amount in the rotation amount storage means and comparing the detected rotation amount with the set target rotation amount (including an allowable range); Are provided.

According to a second aspect of the present invention, there is provided an electric rotary tool having a screw tightening state determination function, an electric motor, a drive switch for driving the electric motor, and a drive output shaft of the electric motor via a reduction mechanism. And a driver bit coupled to each other, a switch operating member that operates the drive switch, an encoder that detects a rotation stop state based on a stop torque of the electric motor, and an electric motor that controls driving and stop of the electric motor An electric rotary tool provided with a motor control circuit and a rotation amount detection means for detecting the rotation amount of the electric motor,
A screw tightening start time memory for detecting and recording a screw tightening start time when screw tightening is performed by an operation signal of the operation switch or encoder, provided with a drive switch or an encoder that operates when the screw of the screwdriver bit is in contact with an object to be mounted. Means,
The rotation amount of the electric motor due to the rotation of the driver bit from the start time of the screw tightening to the stop time of the rotation based on the stop torque of the electric motor accompanying the completion of the screw tightening is determined by the screw tightening operation by the first multiple times. Rotation amount storage which detects by the amount detection means, records the detected rotation amount, and sets a target rotation amount (including an allowable range) on condition that the plurality of screw tightening states are all appropriate. Means,
In the subsequent screw tightening operation, the rotation amount detection means detects the rotation amount of the electric motor due to the rotation of the driver bit from the start time of the screw tightening to the rotation stop time based on the stop torque of the electric motor accompanying the completion of the screw tightening. Sequentially detecting and recording in the rotation amount storage means, and comparing the detected rotation amount with the set target rotation amount (including an allowable range) to determine whether the screw tightening state is good or bad. And a control means for controlling.

According to a third aspect of the present invention, there is provided an electric rotary tool having a screw tightening state determination function according to the first aspect of the present invention, wherein the electric rotary tool has a screw tightening state determination function according to the first aspect. A load current detecting means for detecting a load current obtained in the electric motor based on a load torque (reaction force) applied to the bit;
A load current value proportional to a screw tightening torque value of the electric motor at the time of clutch operation by the clutch mechanism accompanying the completion of screw tightening from the start of screw tightening by a plurality of first screw tightening operations is calculated as the load current detecting means. Load current value storage means for recording the detected load current value and setting a target load current value (including an allowable range) on the condition that the plurality of screw tightening states are all appropriate. Provided,
In the subsequent screw tightening operation, the control means receives a load current value proportional to the screw tightening torque value of the electric motor from the start of the screw tightening to the time of clutch operation by the clutch mechanism accompanying the completion of the screw tightening. By sequentially detecting the current detection means and recording it in the load current value storage means, and comparing the detected load current value with the set target load current value (including an allowable range), It is characterized in that the control is performed so as to determine whether the quality is good or bad.

According to a fourth aspect of the present invention, there is provided an electric rotary tool having a screw tightening state determining function according to the present invention. The electric rotary tool having the screw tightening state determining function according to the second aspect, wherein the driver in the electric motor control circuit is A load current detecting means for detecting a load current obtained in the electric motor based on a load torque (reaction force) applied to the bit;
The load current value proportional to the screw tightening torque value of the electric motor at the rotation stop time based on the stop torque of the electric motor accompanying the completion of screw tightening from the screw tightening start time by the screw tightening operation by the first multiple times, Detected by the load current detecting means, records the detected load current value, and sets a target load current value (including an allowable range) on condition that the plurality of screw tightening states are all appropriate. Provide load current value storage means,
In the control means, in a subsequent screw tightening operation, a load proportional to the screw tightening torque value of the electric motor at the rotation stop time based on the stop torque of the electric motor accompanying the completion of screw tightening from the start time of the screw tightening. Current values are sequentially detected by the load current detection means and recorded in the load current value storage means, and the detected load current value is compared with the set target load current value (including an allowable range). Thus, the control is performed so as to determine whether the screw tightening state is good or bad.

  According to a fifth aspect of the present invention, there is provided an electric rotary tool having a screw tightening state determination function, which is operated by an axial displacement of a driver bit as a drive switch that operates when the screw of the driver bit is brought into contact with an object to be attached. A push operation switch is provided, and a screw tightening start time when screw tightening is set by an operation signal of the push operation switch.

  According to a sixth aspect of the present invention, there is provided an electric rotary tool having a screw tightening state determination function, wherein the control means records the clutch operation time point or the stoppage recorded in the rotation amount storage means during a subsequent screw tightening operation. When it is determined that the rotation amount of the electric motor detected at the time of rotation stop based on the dynamic torque matches the set target rotation amount (including the allowable range), and / or recorded in the load current value storage means The load current detection value proportional to the screw tightening torque value of the electric motor detected at the clutch operation time or the rotation stop time based on the stop torque is set to the set target load current value (including the allowable range). When it is determined that it is suitable, the screw tightening state is determined to be appropriate and recorded or displayed.

  According to a seventh aspect of the present invention, there is provided an electric rotary tool having a screw tightening state determining function, wherein the control means performs a subsequent screw tightening operation during or after the clutch operation recorded in the rotation amount storage means. When it is determined that the amount of rotation of the electric motor during operation or when the rotation is stopped or not based on the stationary torque does not match the set target rotation amount (including the allowable range), and / or The load current detection value proportional to the screw tightening torque value of the electric motor at the clutch operation time or the rotation stop time based on the stall torque recorded in the load current value storage means is set as a set target load current value ( If it is determined that it does not conform to (including the allowable range), the screw tightening state is determined to be defective, and is recorded or displayed.

  The electric rotary tool having the screw tightening state determination function according to claim 8 of the present invention is the screw of which the screw tightening state is determined to be appropriate when the control means determines that the screw tightening state is appropriate. The present invention is characterized in that the number and / or length dimension thereof is detected and recorded.

  According to the electric rotary tool having the screw tightening state determination function according to the first and second aspects of the present invention, the screwdriver is connected to the drive output shaft of the electric motor via the clutch mechanism to perform the screw tightening operation. As the first screw tightening operation, the clutch operation by the clutch mechanism is detected by the clutch operation detection sensor, and the rotation amount detection signal obtained by the rotation amount detection means of the electric motor is used. The operation for detecting the rotation amount based on the rotation amount is repeated a plurality of times to set the target rotation amount (including the allowable range) based on the detection record of the rotation amount, and is detected in the subsequent screw tightening operation. By comparing the rotation amount with the set target rotation amount (including the permissible range), it is possible to easily and simply confirm the quality of the screw tightening state appropriately. It can be. Therefore, if the electric rotating tool of the present invention is used, even an unskilled screw tightening operator can easily and accurately perform the screw tightening operation.

  According to the electric rotary tool having the screw tightening state determination function according to claim 2 of the present invention, the screwdriver is coupled with the driver bit without providing a clutch mechanism on the drive output shaft of the electric motor so as to perform the screw tightening operation. Rotation amount detection obtained by the rotation amount detection means of the electric motor by detecting the rotation stop state based on the stopping torque of the electric motor as the first screw tightening operation using the electric rotating tool configured The operation for detecting the rotation amount based on the signal is repeated a plurality of times to set the target rotation amount (including the allowable range) based on the detection record of the rotation amount. By comparing the rotation amount to be set with the set target rotation amount (including the allowable range), it is possible to easily and easily confirm whether the screw tightening state is good or not. It can be. Therefore, if the electric rotating tool of the present invention is used, even an unskilled screw tightening operator can easily and accurately perform the screw tightening operation.

  According to the electric rotary tool having the screw tightening state determination function according to the third and fourth aspects of the present invention, when the clutch operation by the clutch mechanism is detected by the clutch operation detection sensor in the configuration of the electric rotary tool described above. Alternatively, when the rotation stop state is detected based on the stationary torque of the electric motor, the load current value is detected based on the load current detection signal obtained by the load current detection means in the electric motor control circuit. By performing the detection simultaneously with the detection, the target rotation amount (including the allowable range) and the target load current value (including the allowable range) are set, and the rotation amount and the load current detected in the subsequent screw tightening operation. By comparing the value with the target rotation amount (including the allowable range) and the target load current value (including the allowable range), respectively, It can be confirmed in the proper quality of the screw tightening state as easily and conveniently.

  According to the electric rotary tool having the screw tightening state determination function according to claim 5 of the present invention, it is possible to accurately detect the rotation amount of the electric motor during the actual screw tightening operation, Based on this, it is possible to facilitate detection of various abnormal states of screw tightening, and to reliably confirm and determine an appropriate screw tightening state in the screw tightening operation. In this way, according to the present invention, data relating to control detected in the clutch-type electric rotary tool to be used or image processing is smoothly and easily achieved, and the control data processing function as the electric rotary tool is enhanced. be able to.

  According to the electric rotary tool having the screw tightening state determination function according to claims 6 and 7 of the present invention, for example, the rotation amount of the electric motor is set to the target rotation amount (allowable) together with the above-mentioned screw tightening state determination. If the motor rotation amount is larger than the target rotation amount (including the permissible range), or the rotation amount of the electric motor is greater than the target rotation amount (including the allowable range) It is possible to easily determine whether or not the screw tightening is abnormal as an abnormal state such as a screw fool, wear of a pilot hole, screw cam-out, breakage of a bit, or incompatibility of a selected screw size. Therefore, according to the present invention, it is possible to easily perform detection and confirmation of human and physical work mistakes as well as reducing the defective rate in the above-described screw tightening work.

  According to the electric rotary tool having the screw tightening state determination function according to the eighth aspect of the present invention, as described above, the quality determination of the screw tightening state can be performed very easily and accurately. The number of screws judged to be proper can be distinguished from the number of screws judged to be abnormal or defective, and can be recorded reliably in the control unit, and the number of these recorded screws can be confirmed or displayed. By doing so, the reliability of the screw tightening operation can be improved as well as the efficiency. Similarly to the above, when the screw tightening state is determined to be appropriate, the length of the screw tightened screw is accurately recorded by the control means based on the rotation amount detected during the clutch operation. Further, the recorded contents recorded can be displayed.

It is explanatory drawing which shows the schematic structure which shows one embodiment of the electric rotary tool provided with the screw-tightening state determination function based on this invention, and its control system. It is a control system diagram of the electric rotary tool provided with the screw tightening state determination function according to the present invention shown in FIG. It is a flowchart figure which shows the screw tightening control program as a basic control operation method for performing screw tightening quality determination with the electric rotary tool provided with the screw tightening state determination function shown in FIG. It is a flowchart figure which shows the screw tightening control program as an additional control operation method for performing screw tightening quality determination with the electric rotary tool provided with the screw tightening state determination function shown in FIG. It is explanatory drawing which shows the schematic structure which shows another embodiment of the electric rotary tool provided with the screw-tightening state determination function based on this invention, and its control system.

  Next, an embodiment of an electric rotary tool having a screw tightening state determination function according to the present invention will be described in detail with reference to the accompanying drawings.

[ Configuration example (1) of an electric rotary tool having a screw tightening state determination function ]
FIG. 1 is a schematic configuration explanatory view showing an embodiment of an electric rotary tool having a screw tightening state determination function according to the present invention. That is, in FIG. 1, reference numeral 10 indicates an electric rotary tool. An electric motor 12, a drive switch 13 for driving the electric motor 12, and the electric motor 12 are provided in a grip portion of the electric rotary tool 10. A speed reduction mechanism 16 and a clutch mechanism 18 coupled to a drive output shaft (not shown) are respectively built in, and a driver bit 20 is coupled via the clutch mechanism 18.

  In the electric rotary tool 10, a switch operation member 14 that operates the drive switch 13 of the electric motor 12, an electric motor control circuit 22 that performs drive control and stop control of the electric motor 12, and a clutch operation of the clutch mechanism 18. And a clutch operation detection sensor 28 for detecting the above. The electric motor control circuit 22 is provided with a rotation amount detecting means 24 for detecting the rotation amount of the precursor electric motor 12. Furthermore, load current detection means 26 for detecting the load current obtained in the electric motor 12 based on the load torque (reaction force) applied to the driver bit 20 is appropriately provided.

  In the electric rotary tool 10 of the present embodiment, a brushless motor can be suitably used as the electric motor 12. The switch operating member 14 for operating the drive switch 13 to drive the electric motor 12 can be configured as a known lever member provided on the outer periphery of the gripping portion of the electric rotary tool 10, for example.

  Further, in this embodiment, the rotation amount detection means 24 for detecting the rotation amount of the electric motor 12 counts the pulses generated at the time of magnetic pole detection with respect to the Hall element that detects the magnetic pole of the rotor in the brushless motor. It can be provided as a means. In this case, the count number of the pulses detected by the rotation amount detection means 24 can be detected and recorded as a rotation amount correlated with the screw tightening rotation amount in the screw tightening operation accompanying the rotation of the driver bit 20.

  Furthermore, the load current detection means 26 for detecting the load current of the electric motor 12 can be provided as means for detecting the load current in the power supply circuit of the electric motor 12. In this case, the detected load current value of the electric motor 12 can be detected and recorded as a load current value correlated with a screw tightening torque value in the screw tightening operation accompanying the rotation of the driver bit 20.

  As the clutch mechanism 18, for example, a clutch plate is attached to the output shaft of the speed reduction mechanism 16, and a clutch ball is elastically engaged with the clutch plate in the axial direction. When a load torque (reaction force) above a certain level is applied to the output shaft, the clutch plate gets over the clutch ball, and the transmission of the rotational driving force to the bit holder that engages and holds the driver bit 20 is cut off. Thus, the screw can be tightened with a preset torque. In this case, when the clutch ball is elastically engaged with the clutch plate, the screw tightening torque can be set by appropriately adjusting the elasticity.

  The clutch operation detection sensor 28 for detecting the clutch operation of the clutch mechanism 18 includes, for example, a limit switch that operates by displacement of the clutch plate at the time of clutch operation, and an internal that constitutes the deceleration mechanism 16 that idles at the time of clutch operation. It can be configured by a known means such as a magnetic sensor for detecting the rotation of the gear.

  Therefore, in the present embodiment, a control unit 30 is provided as a control means for determining the screw tightening state, and the CPU 32 uses a screw for the electric motor control circuit 22 provided in the electric motor 12 in the electric rotary tool 10. When starting the tightening operation, a drive switch operation signal S13 obtained by the operation of the drive switch 13 operated by the switch operation member 14 is input, and a motor drive control signal S22a is generated based on the drive switch operation signal S13. It is configured to output and input to the electric motor control circuit 22 to perform drive control of the electric motor 12.

  When the required screw tightening operation is performed by driving the electric motor 12, the CPU 32 detects the rotation amount detected by the rotation amount detection means 24 at the driving start time t0 of the electric motor 12 accompanying the start of the screw tightening operation. Based on the detection signal S24, the rotation amount Rt of the electric motor 12 is set to be detected and recorded.

  Further, similarly to the above, at the driving start time t0 of the electric motor 12 accompanying the start of the screw tightening operation, it is proportional to the screw tightening torque value based on the load current detection signal S26 detected by the load current detecting means 26. The load current value It is set to be detected and recorded.

  The CPU 32 detects the amount of rotation of the electric motor 12 at the clutch operation time t1 obtained based on the clutch operation detection signal S28 detected by the clutch operation detection sensor 28 at the clutch operation time of the clutch mechanism 18. Thus, setting of a target rotation amount Rm ± α (± α is an allowable range), which will be described later, and a rotation amount Rt1 for comparison with the target rotation amount Rm ± α are set to be detected and recorded.

  Similarly to the above, the load current proportional to the screw tightening torque value at the clutch operation time t1 obtained based on the clutch operation detection signal S28 detected by the clutch operation detection sensor 28 at the clutch operation time of the clutch mechanism 18. By detecting a value, a setting of a target load current value Im ± β (± β is an allowable range) described later and a load current value It1 for comparison with the target load current value Im ± β are detected and recorded. Set to.

  As described above, when the clutch operation is detected by the clutch operation detection sensor 28, the motor stop control signal S22b is output via the CPU 32 and also input to the electric motor control circuit 22, and the electric motor 12 stop control is performed.

  Further, in the present embodiment, as described above, the CPU 32 of the control unit 30 compares the rotation amount Rt1 detected at the clutch operation time t1 with the target rotation amount Rm ± α set in advance. When it is determined whether the screw tightening state is good and / or, by comparing the load current value It1 detected at the clutch operation time t1 with a preset target load current value Im ± β, the screw tightening state When the quality is determined, the determination content is appropriately displayed on the display device 40 by any one of the screw tightening determination signals S40 output from the CPU 32.

  Next, regarding the control operation method of the electric rotary tool having the screw tightening state determination function according to the present invention having the above-described configuration, the steps until the pass / fail determination of the screw tightening state in the screw tightening operation is performed. Description will be made based on a control system diagram and a flowchart showing its control operation.

[ Control operation method of electric rotating tool according to the present invention (1) ]
2 shows a control system of the control unit 30 of the electric rotary tool having the screw tightening state determination function according to the present invention shown in FIG. 1, and FIG. 3 shows the screw tightening state determination function according to the present invention shown in FIG. It is a flowchart which shows the control operation method of the said control part 30 of the electric rotary tool provided with.

  In FIG. 2, in the control system of the control unit 30 of the present invention, a CPU 32 indicates a processor that controls the whole, and the operation switch (encoder) 13, rotation amount detection means 24, load current detection means 26 described above via a data bus. The electric motor control circuit 24 is connected. A ROM 50 storing a control program is connected to the data bus of the CPU 32, and the electric rotary tool 10 detected by the operation switch (encoder) 13, rotation amount detection means 24, and load current detection means 26. A RAM 60 is connected as storage means for storing detection data and the like associated with the operation.

  That is, in the RAM 60, a screw tightening start time storage unit 61 that records and sets the screw tightening start time, and a rotation amount storage unit that records the rotation amount detected by the rotation amount detection means 24 and sets the target rotation amount. 62, and a load current value storage unit 63 for recording a load current value detected by the load current detecting means 26 and setting a target load current value.

  Further, an LCD 40a as a display for performing external display based on various data stored in the RAM 60 is connected to the data bus of the CPU 32 via an LCD IC 40b as a control circuit thereof, and an external operation is appropriately performed. An input / output circuit 52 for inputting / outputting data and the like is connected by a device.

  Next, as a control operation method of the electric rotary tool 10 according to the present invention, the control operation method shown in FIG. 3 will be described based on the configuration of FIG. 1 and the control system of the control unit 30 shown in FIG.

  First, when driving the electric rotary tool 10 according to the present invention, the drive switch 13 is operated by operating the switch operating member 14, and the motor drive control signal S22a is input to the electric motor control circuit 22, so that the electric motor is operated. 12 is controlled, and driving of the electric driver 10 is started (see FIGS. 1 and 2). When the electric rotary tool 10 is used for the first time, standard torque adjustment is performed on the clutch mechanism 18 in advance.

  Therefore, when the electric rotary tool 10 of the present invention is used for the first time, as a first screw tightening operation, a screw tightening operation on a desired object to be screwed is performed from 1 to n times (STEP- 1). In this case, the operation of the drive switch 13 provided in the electric rotary tool 10 detects the screw tightening start time t0 as the drive start time of the electric motor 12, and records it in the screw tightening start time storage unit 61 of the RAM 60 (FIG. 2).

  At the same time, the rotation amount detection signal S24 provided in the electric rotary tool 10 starts counting the rotation amount of the electric motor 12 that is proportional to the rotation amount of the driver bit 20 that performs screw tightening. Then, the screw tightening rotation amount counted until t1 when the screw tightening by the driver bit 20 is performed and the clutch operation by the clutch mechanism 18 is performed is recorded in the rotation amount storage unit 62 of the RAM 60 (STEP-2). ).

  In this way, in the screw tightening operation performed a plurality of times, the screw tightening rotation amount recorded in the rotation amount storage unit 62 is set on the condition that all the screw tightening states are properly performed. Based on this, the rotation amount storage unit 62 automatically sets the target rotation amount Rm ± α (± α is an allowable range) (STEP-3).

  As described above, in the electric rotary tool 10 of the present invention, the target rotation amount Rm ± α (± α is an allowable range) is set, so that a required screw tightening operation thereafter can be performed (STEP). -4). Therefore, when performing the required screw tightening operation by the electric rotating tool 10 thereafter (STEP-4), the time t1 when the clutch operation by the clutch mechanism 18 is performed from the screw tightening start time t0 as in the case described above. The screw tightening rotation amount counted until then is detected and recorded in the rotation amount storage unit 62 (STEP-5).

  The screw tightening rotation amount Rt1 thus detected is compared with the target rotation amount Rm ± α (± α is an allowable range) set in the rotation amount storage unit 62 (STEP-6). Based on this, it is set to determine whether the screw tightening state is good or bad. That is, when comparing the detected screw tightening rotation amount Rt1 with the target rotation amount Rm ± α (± α is an allowable range), if the condition of Rm + α ≧ Rt1 ≧ Rm−α is satisfied, proper screw tightening is performed. If the condition is not satisfied (STEP-7) and the condition is not satisfied, it is determined that the screw is in a defective or abnormal screw tightening state (STEP-8).

  It should be noted that, when the screw tightening operation by using the electric rotary tool 10 and the subsequent screw tightening operation (STEP-1 and STEP-4) are started, the motor is electrically driven based on the rotation amount detection signal S24 detected by the rotation amount detection means 24. When the rotation amount Rt of the motor 12 is recorded in the rotation amount storage unit 61, the rotation of the electric motor 12 during the actual screw tightening operation after the driver bit 20 comes into contact with the screw attachment object. If the amount Rt is detected, an accurate amount of rotation can be detected.

  Therefore, in the electric rotary tool 10 of the present invention, for example, as proposed by the present applicant in Japanese Patent No. 4721535, in the electric screwdriver 10, the axial direction at the time of contact of the screwdriver bit 20 with an object to which a screw is to be attached. A push operation switch (not shown) that is actuated by the displacement of the screw operation is provided, and the screw tightening start time t0 when performing the screw tightening operation can be set by an operation signal of the push operation switch.

  In this way, when it is determined whether the screw tightening state is good or bad, a determination display that can clearly distinguish between the appropriateness determination and the failure determination can be performed. Therefore, the electric rotary tool 10 according to the present invention is configured such that each determination content is appropriately displayed on the LCD 40a serving as a display by one of the screw tightening determination signals S40 output from the control unit 30. (See FIGS. 1 and 2).

[ Control operation method of the electric rotary tool according to the present invention (2) ]
FIG. 4 is a flowchart showing another control operation method of the control unit 30 of the electric rotary tool according to the present invention shown in FIG. That is, the control operation method shown in FIG. 4 is based on the control operation method shown in FIG. 3 and further shows a control operation method added.

  Therefore, the control operation shown in FIG. 4 is performed in parallel with the control operation method (1). Therefore, in the case where the screw tightening operation for the required screw tightening object is performed once to n multiple times by the first screw tightening operation at the first use of the electric rotary tool 10 (STEP-11), In the same manner as in the control operation method, the screw tightening start time t0 that is the drive start time of the electric motor 12 is detected by the operation of the drive switch 13 provided in the electric rotary tool 10, and the screw tightening start time storage unit of the RAM 60 is detected. 61 (see FIG. 2).

  At the same time, detection of the load current value It proportional to the screw tightening torque value of the electric motor 12 is started by the load current detection means 26 provided in the electric rotary tool 10. Then, the load current value of the electric motor 12 sequentially detected by the time t1 when the screw tightening by the driver bit 20 is performed and the clutch operation by the clutch mechanism 18 is performed is recorded in the load current value storage unit 63 of the RAM 60, respectively. (STEP-12).

  In this way, in the screw tightening operation performed a plurality of times, the load current values recorded in the load current value storage unit 63 are respectively set on condition that all the screw tightening states are properly performed. Based on this, the load current value storage unit 63 automatically sets the target load current value Im ± β (± β is an allowable range) (STEP-13).

  As described above, in the electric rotary tool 10 of the present invention, the target load current value Im ± β (including the allowable range) is set, so that the necessary screw tightening operation thereafter can be performed (STEP). -14). Therefore, when performing the required screw tightening work by the electric rotating tool 10 thereafter (STEP-14), the time t1 when the clutch operation by the clutch mechanism 18 is performed from the screw tightening start time t0 as in the case described above. Until then, the load current value It1 of the electric motor 12 is sequentially detected and recorded in the rotation amount storage unit 63 (STEP-15).

  The load current value It1 thus detected is compared with the target load current value IRm ± β (± β is an allowable range) set in the load current value storage unit 63 (STEP-16), and as a result. Is set to determine whether the screw tightening state is good or bad. That is, when comparing the detected load current value It1 and the target load current value Im ± β (± β is an allowable range), if the condition of Im + β ≧ It1 ≧ Im−β is satisfied, proper screw tightening is performed. If the condition is not satisfied (STEP-17) and the condition is not satisfied, it is determined to be a defective or abnormal screw tightening state (STEP-18).

  In the above-described electric rotary tool 10 of the present invention, the control operation method (2) is performed in parallel with the control operation method (1) described above.

  That is, in the first plural screw tightening operations, the rotation amount Rt1 of the electric motor 12 due to the rotation of the driver bit 20 from the screw tightening start time t0 to the clutch operation time t1 by the clutch mechanism 18 accompanying the completion of screw tightening. Is detected by the rotation amount detecting means 24, the detected rotation amount is recorded, and the target rotation amount Rm ± α (± α is an allowable range on the condition that the plurality of screw tightening states are all appropriate. ) Is set in the rotation amount storage unit 62. At the same time, a load current value It1 proportional to the screw tightening torque value of the electric motor 12 detected by the load current detecting means 26 is detected, the detected load current value is recorded, and the plurality of screw tightening states are detected. The target load current value IRm ± β (± β is an allowable range) is set in the load current value storage unit 63 on the condition that all are appropriate.

  In the subsequent screw tightening operation, the rotation amount detection means 24 determines the rotation amount Rt1 of the electric motor due to the rotation of the driver bit 20 from the start time of the screw tightening to the clutch operation time by the clutch mechanism 18 when the screw tightening is completed. The rotation amount is detected and recorded in the rotation amount storage unit 62, and the rotation amount detected at the time of the clutch operation is compared with the set target rotation amount Rm ± α (± α is an allowable range). At the same time, the load current value It1 from the start time of the screw tightening to the time of clutch operation by the clutch mechanism when the screw tightening is completed is sequentially detected by the load current detecting means 26 and recorded in the load current value storage unit 63. At the same time, the load current value detected at the time of clutch operation is compared with the set target load current value IRm ± β (± β is an allowable range). Then, it is possible to determine whether the screw tightening state is good or bad by the control unit 30 and confirm that the screw tightening state is mutually appropriate.

  Therefore, also in the control operation method (2), when it is determined whether the screw tightening state is good or bad, each determination content is appropriately displayed by the one of the screw tightening determination signals S40 output from the control unit 30. The LCD 40a can be displayed (see FIGS. 1 and 2).

  In the embodiment described above, in the electric rotary tool according to the present invention, as a basic configuration thereof, the clutch mechanism 18 is provided, and the clutch detection sensor 28 for detecting the clutch operation of the clutch mechanism 18 is provided. The amount of rotation of the electric motor 12 with respect to the rotation of the driver bit 20 accompanying the completion of screw tightening from the start of tightening, and the load current value of the electric motor based on the load torque (reaction force) applied to the driver bit 20 are detected. Explained when to do.

  However, the electric motor 12 is provided with a rotation stop state when the rotational drive of the electric motor reaches the stop torque upon completion of screw tightening based on the stop torque set in the electric motor 12. Therefore, the amount of rotation of the electric motor 12 accompanying the completion of screw tightening from the start of screw tightening can also be detected by detecting the rotation stop time based on the stationary torque of the electric motor 12. It is also possible to properly detect the load current value of the electric motor 12.

  Therefore, in the above-described embodiment, instead of providing the clutch mechanism and the clutch detection sensor, the driver bit of the rotation from the screw tightening start time to the rotation stop time based on the stop torque of the electric motor accompanying the completion of screw tightening is changed. It is configured to detect the amount of rotation of the electric motor with respect to the rotation, and the screw tightening torque value of the electric motor at the time of rotation stop based on the stop torque of the electric motor accompanying the completion of screw tightening from the time of screw tightening start. It can be configured to detect a proportional load current value.

[ Configuration example (2) of an electric rotary tool having a screw tightening state determination function ]
FIG. 5 is a schematic configuration explanatory diagram showing another embodiment of the electric rotary tool having a screw tightening state determination function according to the present invention. For convenience of explanation, the same constituent elements as those of the apparatus of the embodiment shown in FIG. 1 described above have the same functions, and thus the same reference numerals are given and detailed descriptions thereof are omitted. .

  That is, in the electric driver 10 ′ of the present embodiment, an electric motor other than the brushless motor can be applied as the electric motor 12, so that the rotation amount detecting means of the electric motor 12 is the driving shaft of the electric motor 12. The first encoder 25 made of a known rotary encoder is provided. Accordingly, in the present embodiment, the rotation amount of the electric motor 12 is determined as the rotation amount detection means by inputting the encoder detection signal S25 detected by the first encoder 25 to the CPU 32 of the control unit 30. Can be set. In this case, the encoder detection signal S25 detected by the first encoder 25 can be detected and recorded as a rotation amount correlated with a screw tightening rotation amount at the time of screw tightening of the driver bit 20 rotated by the electric motor 12. it can.

  Further, in the electric driver 10 ′ of the present embodiment, a second encoder 29 including a known rotary encoder coupled to the driver bit 20 can be provided as a rotation amount detection unit of the driver bit 20. Accordingly, the rotation amount of the driver bit 20 can be set as rotation amount detection means by inputting the encoder detection signal S29 detected by the second encoder 29 to the CPU 32 of the control unit 30. . In this case, the encoder detection signal S29 detected by the second encoder 29 can be detected and recorded as a rotation amount correlated with the screw tightening rotation amount in the screw tightening operation by the rotation of the driver bit 20.

  The other configuration of the electric rotary tool 10 ′ of the present embodiment is the same as that of the above-described embodiment. Therefore, the CPU 32 of the control unit 30 sets a preset target rotation amount Rm in the same manner as in the above-described embodiment. By comparing the rotation amount Rt1 detected at the clutch operation time point t1 with respect to ± α, whether or not each of the above-described screw tightening states is determined and / or a preset target load current value Im By comparing the load current value It1 detected at the clutch operation time t1 with ± β to determine whether or not each of the above-described screw tightening states is acceptable, any of the above-described screw tightening determinations output from the CPU 32 Each determination content is appropriately displayed on the display 40 by the signal S40.

  As shown in the present embodiment, the first encoder 25 or the second encoder 29 that detects a rotation amount correlated with the screw tightening rotation amount during the screw tightening operation and screw tightening operation of the driver bit 20 is used. By doing so, it is possible to detect and record the screw tightening start time t0 when performing the screw tightening appropriately and easily.

  As is clear from the above embodiments, according to the electric rotary tool according to the present invention, in a predetermined screw tightening operation using various screws or the like, from the start of screw tightening to a required screw hole until the screw is seated. If the amount of rotation of the electric motor can be detected up to about 50%, half of the trouble that results in screw tightening failure in the screw tightening operation can be confirmed and solved. In other words, it is called the four major troubles of screw tightening, (1) screw galling generated at the entrance by slant tightening to the pilot hole of the screw, and (2) work piece and pilot hole generated when tightening the tapping screw etc. It is possible to confirm each of the screw floats that torque up before sitting due to a problem. These troubles occur during about half the length of the screw from the start of screw tightening. And when these conditions are cleared and the specified screw tightening torque after screw seating is reached, (3) If the camout occurs due to bit wear etc. and the specified screw tightening torque cannot be achieved, (4) By detecting and confirming the amount of rotation of the electric motor and the torque-up signal by the clutch mechanism, such as poor screw fastening due to wear of the pilot hole, the above four major troubles of screw tightening work require skill respectively. Therefore, it is possible to obtain an excellent effect that detection can be performed easily and reliably.

  Further, according to the electric rotary tool according to the present invention, when the plurality of preset screws are sequentially tightened in the required screw tightening operation, the above-described screw tightening state of each screw is acceptable. At the same time, the detection and recording of the screw tightening can be performed at the same time, and the number of screw tightening can be detected and recorded at the same time, making it easy to build a production management system for various screw tightening operations and their networks. It becomes.

  In particular, according to the electric rotary tool according to the present invention, in the required screw tightening operation, the proper screw tightening completion (screw tightening operation) is achieved by properly detecting the rotation amount of the electric motor by the electric screwdriver using the clutch mechanism. It is possible to easily and reliably determine the (sitting) state, and to record or display each screwing state in relation to the number of screws to be subjected to many continuous screwing. Also, by detecting and recording the load current of the electric motor at the time of clutch operation in each screw tightening operation, the load current value at the time of clutch operation is the screw tightening torque value of the screw that has been completely screwed (seated), respectively. Therefore, various settings can be made by detecting the amount of rotation of the electric motor and setting the load current value of the electric motor to be detected and recorded or displayed in combination with the detection of the rotation amount of the electric motor. It becomes possible to easily construct a production management system in a production line for performing screw tightening work and a network thereof.

  As described above, as a preferred embodiment of the present invention, the case where screw tightening control is performed using an ordinary screw on an object provided with an ordinary screw hole has been described, but the present invention is not limited to such an embodiment. For example, the present invention can be similarly applied to an electric rotary tool that performs screw tightening control using a tapping screw or a drill screw or performs screw processing using a tap.

DESCRIPTION OF SYMBOLS 10,10 'Electric rotary tool 12 Electric motor 13 Drive switch 14 Switch operation member 16 Deceleration mechanism 18 Clutch mechanism 20 Driver bit 22 Electric motor control circuit 24 Rotation amount detection means 25 1st encoder (rotation amount detection means)
26 Load current detection means 28 Clutch operation detection sensor 29 Second encoder (rotation amount detection means)
30 control unit 32 CPU
40 Display 40a LCD 40b LCDIC
50 ROM 52 I / O circuit 60 RAM 61 Screw tightening start time storage unit 62 Rotation amount storage unit 63 Load current value storage unit S13 Drive switch operation signal S22a Motor drive control signal S22b Motor stop control signal S24 Rotation amount detection signal S25 Encoder detection signal S26 Load current detection signal S28 Clutch operation detection signal S29 Encoder detection signal S40 Screw tightening state determination signal Rm ± α Target rotation amount (including allowable range)
Im ± β Target load current value (including allowable range)
t0 Electric motor drive start time / screw tightening start time t1 Clutch operation time Rt1 Rotation amount at clutch operation time It1 Load current detection value at clutch operation time

In order to achieve the above object, an electric rotary tool having a screw tightening state determining function according to claim 1 of the present invention includes an electric motor, a drive switch for driving the electric motor, and driving of the electric motor. A driver bit coupled to the output shaft via a speed reduction mechanism and a clutch mechanism, a switch operation member for operating the drive switch, a clutch operation detection sensor for detecting a clutch operation of the clutch mechanism, and an electric motor An electric motor control circuit that performs drive and stop control, and a rotation amount detection means that detects a rotation amount of the electric motor, each of which includes an electric rotary tool,
Wherein the driving switch or encoder operates at abutment provided for mounting the object the driver bit of the screw, the screw tightening start time storage for screwing beginning the detection record when performing the screw fastening by the operation signal of the drive switch or encoder Means,
The rotation amount detecting means detects the rotation amount of the electric motor relative to the rotation of the driver bit from the start time of the screw tightening to the clutch operation time due to the completion of the screw tightening by the screw tightening operation by the first plural times. A rotation amount storage means for recording the detected rotation amount and setting a target rotation amount (including an allowable range) on condition that the plurality of screw tightening states are all appropriate;
In the subsequent screw tightening operation, the rotation amount detection means sequentially detects the rotation amount of the electric motor relative to the rotation of the driver bit from the screw tightening start time to the clutch operation time by the clutch mechanism when the screw tightening is completed. Control means for controlling the screw tightening state to be judged by recording the rotation amount in the rotation amount storage means and comparing the detected rotation amount with the set target rotation amount (including an allowable range); Are provided.

According to a second aspect of the present invention, there is provided an electric rotary tool having a screw tightening state determination function, an electric motor, a drive switch for driving the electric motor, and a drive output shaft of the electric motor via a reduction mechanism. And a driver bit coupled to each other, a switch operating member that operates the drive switch, an encoder that detects a rotation stop state based on a stop torque of the electric motor, and an electric motor that controls driving and stop of the electric motor An electric rotary tool provided with a motor control circuit and a rotation amount detection means for detecting the rotation amount of the electric motor,
Wherein the driving switch or encoder operates at abutment provided for mounting the object the driver bit of the screw, the screw tightening start time storage for screwing beginning the detection record when performing the screw fastening by the operation signal of the drive switch or encoder Means,
The rotation amount of the electric motor due to the rotation of the driver bit from the start time of the screw tightening to the stop time of the rotation based on the stop torque of the electric motor accompanying the completion of the screw tightening is determined by the screw tightening operation by the first multiple times. Rotation amount storage which detects by the amount detection means, records the detected rotation amount, and sets a target rotation amount (including an allowable range) on condition that the plurality of screw tightening states are all appropriate. Means,
In the subsequent screw tightening operation, the rotation amount detection means detects the rotation amount of the electric motor due to the rotation of the driver bit from the start time of the screw tightening to the rotation stop time based on the stop torque of the electric motor accompanying the completion of the screw tightening. Sequentially detecting and recording in the rotation amount storage means, and comparing the detected rotation amount with the set target rotation amount (including an allowable range) to determine whether the screw tightening state is good or bad. And a control means for controlling.

Incidentally, Oite the electric rotating tool according to the present invention, when the required screwing operation, the rotation amount storage unit to the load current value storage unit, data such as the target rotation amount to the target load current value is set, respectively, generally In particular, when the required screw tightening operation is completed and the power is turned off, the data can be reset. In addition, when resetting the data of the storage unit that has been backed up as appropriate, regardless of such power shutdown, it is possible to provide a conventionally known reset switch or the like so that it can be reset at any time. Of course .
Furthermore, when the electric rotary tool according to the present invention sequentially tightens a plurality of preset screws in a required screw tightening operation, the above-described screw tightening state determination for each screw is performed. Simultaneously with the detection recording, the detection recording of the number of screw tightening can be performed in a lump, and it is possible to easily construct a production line for performing various screw tightening operations and a production management system in those networks.

Claims (8)

An electric motor, a drive switch for driving the electric motor, and a driver bit coupled to a drive output shaft of the electric motor via a speed reduction mechanism and a clutch mechanism, and a switch operation member for operating the drive switch A clutch operation detection sensor that detects the clutch operation of the clutch mechanism, an electric motor control circuit that performs drive and stop control of the electric motor, and a rotation amount detection means that detects the rotation amount of the electric motor, respectively It consists of an electric rotating tool provided,
A screw tightening start time memory for detecting and recording a screw tightening start time when screw tightening is performed by an operation signal of the operation switch or encoder, provided with a drive switch or an encoder that operates when the screw of the screwdriver bit is in contact with an object to be mounted. Means,
The rotation amount detecting means detects the rotation amount of the electric motor relative to the rotation of the driver bit from the start time of the screw tightening to the clutch operation time due to the completion of the screw tightening by the screw tightening operation by the first plural times. A rotation amount storage means for recording the detected rotation amount and setting a target rotation amount (including an allowable range) on condition that the plurality of screw tightening states are all appropriate;
In the subsequent screw tightening operation, the rotation amount detection means sequentially detects the rotation amount of the electric motor due to the rotation of the driver bit from the screw tightening start time to the clutch operation time by the clutch mechanism accompanying the completion of the screw tightening. Control means for controlling the screw tightening state to be judged by recording the rotation amount in the rotation amount storage means and comparing the detected rotation amount with the set target rotation amount (including an allowable range); The electric rotary tool provided with the screw tightening state determination function characterized by the above. An electric motor, a drive switch for driving the electric motor, a driver bit coupled to a drive output shaft of the electric motor via a speed reduction mechanism, and a switch operating member for operating the drive switch; An encoder that detects a rotation stop state based on a stop torque of the electric motor, an electric motor control circuit that performs drive and stop control of the electric motor, and a rotation amount detection means that detects a rotation amount of the electric motor, respectively It consists of an electric rotating tool provided,
A screw tightening start time memory for detecting and recording a screw tightening start time when screw tightening is performed by an operation signal of the operation switch or encoder, provided with a drive switch or an encoder that operates when the screw of the screwdriver bit is in contact with an object to be mounted. Means,
The rotation amount of the electric motor with respect to the rotation of the driver bit from the start time of the screw tightening to the rotation stop time based on the stop torque of the electric motor accompanying the completion of the screw tightening by the screw tightening operation by the first multiple times Rotation amount storage which detects by the amount detection means, records the detected rotation amount, and sets a target rotation amount (including an allowable range) on condition that the plurality of screw tightening states are all appropriate. Means,
In the subsequent screw tightening operation, the rotation amount detection means detects the rotation amount of the electric motor due to the rotation of the driver bit from the start time of the screw tightening to the rotation stop time based on the stop torque of the electric motor accompanying the completion of screw tightening. Sequentially detecting and recording in the rotation amount storage means, and comparing the detected rotation amount with the set target rotation amount (including an allowable range) to determine whether the screw tightening state is good or bad. An electric rotary tool provided with a screw tightening state determination function, characterized by comprising a control means for controlling. 2. The electric rotary tool having a screw tightening state determination function according to claim 1, wherein a load current obtained in the electric motor based on a load torque (reaction force) applied to the driver bit is detected in the electric motor control circuit. Provide load current detection means,
A load current value proportional to a screw tightening torque value of the electric motor at the time of clutch operation by the clutch mechanism accompanying the completion of screw tightening from the start of screw tightening by a plurality of first screw tightening operations is calculated as the load current detecting means. Load current value storage means for recording the detected load current value and setting a target load current value (including an allowable range) on the condition that the plurality of screw tightening states are all appropriate. Provided,
In the subsequent screw tightening operation, the control means receives a load current value proportional to the screw tightening torque value of the electric motor from the start of the screw tightening to the time of clutch operation by the clutch mechanism accompanying the completion of the screw tightening. By sequentially detecting the current detection means and recording it in the load current value storage means, and comparing the detected load current value with the set target load current value (including an allowable range), An electric rotary tool provided with a screw tightening state determination function, characterized in that control is performed so as to determine whether the quality is good or bad. The electric rotary tool having a screw tightening state determination function according to claim 2, wherein the electric motor control circuit detects a load current obtained in the electric motor based on a load torque (reaction force) applied to the driver bit. Provide load current detection means,
The load current value proportional to the screw tightening torque value of the electric motor at the rotation stop time based on the stop torque of the electric motor accompanying the completion of screw tightening from the screw tightening start time by the screw tightening operation by the first multiple times, Detected by the load current detecting means, records the detected load current value, and sets a target load current value (including an allowable range) on condition that the plurality of screw tightening states are all appropriate. Provide load current value storage means,
In the control means, in a subsequent screw tightening operation, a load proportional to the screw tightening torque value of the electric motor at the rotation stop time based on the stop torque of the electric motor accompanying the completion of screw tightening from the start time of the screw tightening. Current values are sequentially detected by the load current detection means and recorded in the load current value storage means, and the detected load current value is compared with the set target load current value (including an allowable range). Thus, an electric rotary tool having a screw tightening state determination function characterized in that control is performed to determine whether the screw tightening state is good or bad.   As a drive switch that operates when the screw of the screwdriver bit is brought into contact with an object to be mounted, a push operation switch that is operated by an axial displacement of the screwdriver bit is provided, and when performing screw tightening by an operation signal of the push operation switch The electric rotary tool having a screw tightening state determination function according to claim 1 or 2, wherein a screw tightening start time is set.   In the control means, during the subsequent screw tightening operation, the rotation amount of the electric motor detected at the clutch operation time or the rotation stop time based on the stalling torque recorded in the rotation amount storage means is set as a target. An electric motor that is detected when it is determined that the rotation amount (including an allowable range) is met and / or when the clutch operation time recorded in the load current value storage means or the rotation stop time based on the stop torque When it is determined that the load current detection value proportional to the screw tightening torque value matches the set target load current value (including the allowable range), the screw tightening state is determined to be appropriate and recorded or displayed. The electric rotary tool provided with the screw tightening state determination function according to any one of claims 1 to 4.   In the control means, during the subsequent screw tightening work, the electric motor of the electric motor at the time of the clutch operation or the inoperative state recorded in the rotation amount storage means, or at the time of the rotation stop or the inoperative state based on the stationary torque When it is determined that the rotation amount does not match the set target rotation amount (including the allowable range), and / or based on the clutch operation time point or the stationary torque recorded in the load current value storage means If it is determined that the load current detection value proportional to the screw tightening torque value of the electric motor at the time of rotation stop does not match the set target load current value (including the allowable range), the screw tightening state is defective. The electric rotary tool provided with the screw tightening state determination function according to any one of claims 1 to 4, characterized in that it is determined and recorded or displayed.   The control unit is configured to detect and record the number of screws and / or the length of the screws determined to be proper when the screw tightening state is determined to be appropriate. An electric rotary tool having the screw tightening state determination function according to claim 6.

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