JPH11351987A - Method and apparatus for determining degradation of pulse wrench - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and an apparatus for determining degradation of pulse wrench easily and accurately through a simple arrangement. SOLUTION: A pulse wrench 1 comprises a power source 10 for continuous rotary drive, a pulse generating section 11 for converting a continuous rotary force tram the power source 10 into an intermittent pulse output, and a forward end part 12 being engaged to a threaded member in order to tighten the threaded member with an intermittent pulse output from the pulse generating section 11. The apparatus for determining degradation of the pulse wrench 1, comprises means 2 for detecting the tightening torque being applied to the threaded member by the intermittent pulse output from the pulse generating section 11 in the form of waveform, a torque signal processing section 30 for operating a tightening torque value from a tightening torque signal detected through the detecting means 2, and means 3 for determining degradation of the pulse wrench, based on the waveform of varying tightening torque value obtained from the torque signal processing section 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and a method for determining deterioration of a pulse wrench. A pulse wrench deterioration determination device for detecting deterioration of a wrench of a type that converts the pulse output into a pulse output and applies a tightening torque to a screw member by the pulse output (these wrenches are collectively referred to as a “pulse wrench”); Further, the present invention relates to a method for determining deterioration of a pulse wrench for determining the deterioration.

[0002]

2. Description of the Related Art A pulse wrench generally includes a power source that is driven to rotate continuously, a pulse generator that converts a continuous rotational force generated by the power source into an intermittent pulse output, and a pulse that is engaged with a screw member. And a tip for tightening the screw member by the intermittent output of the generator.

[0003] In the case of an oil pulse wrench as a pulse wrench, a pulse generating section rapidly increases the rotational energy of a driving source to increase the pressure of oil filled therein to generate a powerful pulse, and the tightening torque is generated by the pulse. Is applied to the screw member. In the case of an impact wrench, the pulse generating section generates an impact (impact) by a hammer mechanism or the like, and applies a tightening torque to the screw member by the impact.

[0004] In such a pulse wrench, a torque sensor such as a strain gauge is provided at the tip end in order to tighten the screw member with a constant torque. As shown in FIG. When the set value (cut torque CT) is reached, a cutoff signal is output to stop driving the drive source. When the tightening is completed, the value of the tightening torque is set to a predetermined upper limit Tmax.
And a predetermined range between the lower limit Tmin and that is, whether the screw member is properly tightened.

A conventional technique for outputting a cutoff signal when the tightening torque reaches a preset value (cut torque CT) and stopping the driving of the driving source is disclosed in Japanese Patent Application Laid-Open No. 8-294875. As disclosed in the official gazette, a driving means having a pulse component in a driving output, a main shaft having a joint with a screw at one end and driven by the driving means to tighten the screw, and detecting a change in torque of the main shaft. An impact-type screw tightening machine including torque detecting means for detecting the number of impacts occurring after seating based on the detection result of the torque detecting means; and a point in time when the number of impacts reaches a predetermined value. There is known an impact-type screw tightening device comprising a control means for shutting off a power source of the driving means.

In this device, the number of times of occurrence of impact after seating is detected from the detection result of the torque detecting means, and when the number of times of occurrence of the impact reaches a predetermined value, the power source of the driving means is shut off. It is described that the variation in the fastening force at the time of cutoff is reduced by simple control logic.

On the other hand, as an apparatus for controlling the use conditions of an impact wrench, as disclosed in Japanese Patent Application Laid-Open No. 62-203776, the air pressure is adjusted and a small amount of lubricating oil is mixed and supplied to the impact wrench. A forced oil supply means for discharging lubricating oil into a supply of compressed air, and a workpiece detection for detecting that the workpiece is between a start position and an end position of a predetermined process of a work line. Means for determining a fastening failure condition by means of, a supply air pressure, a fastening time at one place, the number of fastenings in one work piece, and the cumulative use number of the impact wrench; Is known to have a means for stopping a work line and a means for displaying a decrease in the amount of oil in a lubricating oil tank, and each of the above-described means is housed in a single box to form a unit. .

[0008] This device is for controlling the operating conditions for securing and assuring the tightening torque accuracy of the impact wrench. A small amount of lubricating oil is mixed in the compressed air pressure supplied to drive the impact wrench. By doing so, attention is focused on preventing seizure. When it is detected that the tightening torque has reached a predetermined value, the tightening is terminated.

[0009]

However, while the pulse wrench 1 is used, the pulse generator 11
In the case of an oil pulse wrench, the oil filled therein leaks and decreases. In the case of an impact wrench, the oil wrench deteriorates due to wear of a hammer mechanism for generating an impact.

In the case where the screw member is tightened by using the pulse wrench 1 deteriorated in this way and stopped when the peak of the tightening torque reaches the preset cut torque CT as described above, a detection is made. Even if the apparent tightening torque reaches the cut torque CT, there is a problem that the substantial work (tightening force) by the pulse generator decreases and the axial force of the screw member becomes insufficient.

This means that the impact-type screw tightening device disclosed in Japanese Patent Application Laid-Open No. 8-294875 similarly cuts off the power source of the driving means when the number of times of occurrence of impact after seating has reached a predetermined value. Therefore, when the pulse generation unit is deteriorated, the tightening of the screw member is terminated in a state where the predetermined tightening torque is not reached, and there is a problem that the axial force of the screw member is insufficient.

Also, in the impact wrench use condition management device disclosed in Japanese Patent Application Laid-Open No. 62-203776, the supply air pressure, the fastening time at one location, the number of fastenings in one work piece, and the like. This is to determine the fastening failure condition based on the cumulative number of times the impact wrench has been used, but not to directly determine the deterioration of the pulse generator.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and provides a pulse wrench deterioration determination apparatus and a deterioration determination method capable of accurately and easily determining deterioration of a pulse wrench with a simple configuration. Accordingly, an object of the present invention is to improve the accuracy of a substantial tightening force of a screw member by a pulse wrench.

[0014]

According to a first aspect of the present invention, there is provided an apparatus for determining deterioration of a pulse wrench, comprising: a power source which is driven to rotate continuously; A pulse wrench having a pulse generation unit that converts the pulse output into a pulse output, and a tip that is engaged with the screw member and fastens the screw member by intermittent pulse output of the pulse generation unit. Detecting means for detecting a tightening torque to a screw member by an intermittent pulse output as a waveform, and a torque signal processing unit for calculating a tightening torque value from a tightening torque signal obtained by the detecting means, Determining means for determining deterioration of the pulse wrench based on the waveform of the changing tightening torque value obtained by the torque signal processing unit. A.

According to a second aspect of the present invention, there is provided a pulse wrench deterioration judging device according to the first aspect, wherein the judging means further comprises a tightening torque value obtained by a torque signal processing section. A pulse interval time processing unit for calculating the pulse interval time from the pulse interval time, and determining the deterioration of the pulse wrench based on the number of pulse outputs determined from the pulse interval time determined by the pulse interval time processing unit It is characterized by being.

According to a third aspect of the present invention, in order to achieve the above object, the invention according to the first or second aspect further comprises a tightening means which is provided by a torque signal processing unit. It has a pulse width processing unit that calculates the pulse width of the waveform from the torque value,
It is characterized in that deterioration of the pulse wrench is determined based on the pulse width obtained by the pulse width processing unit.

According to a fourth aspect of the present invention, there is provided a method for determining deterioration of a pulse wrench, in order to achieve the above object, a power source which is driven to rotate continuously, and which converts a continuous torque from the power source into an intermittent pulse output. A pulse wrench having a tip portion that engages a screw member and a tip portion that is engaged with the screw member and tightens the screw member by intermittent pulse output of the pulse generator portion, wherein the thread member is intermittently output by intermittent pulse output. When tightening, the intermittent tightening torque is detected as a waveform, and deterioration of the pulse wrench is determined based on the waveform of the tightening torque.

According to a fifth aspect of the present invention, there is provided a pulse wrench deterioration judging method according to the fourth aspect, wherein the pulse wrench is determined based on the number of pulse outputs obtained from the detected tightening torque waveform. It is characterized in that deterioration of the wrench is determined.

According to a sixth aspect of the present invention, there is provided a pulse wrench deterioration judging method according to the fourth or fifth aspect of the present invention, wherein the pulse generating portion of the pulse wrench is determined based on the detected tightening torque waveform width. It is characterized by determining deterioration.

According to the first aspect of the present invention, the distal end portion is engaged with the screw member, and the continuous torque generated by the power source is converted into an intermittent pulse output by the pulse generator, and the screw member is tightened by the pulse output. At the time of this tightening, the detecting means detects the tightening torque for the screw member as a waveform.
The determining means is a torque signal processing unit that calculates a tightening torque value from the tightening torque signal obtained by the detecting means,
The deterioration of the pulse generator is determined based on the waveform of the changing tightening torque value obtained by the torque signal processor.

According to the second aspect of the present invention, the determining means calculates the pulse interval time by the pulse interval time processing section from the waveform of the tightening torque value obtained by the torque signal processing section, and obtains the pulse interval time from the pulse interval time. The deterioration of the pulse wrench is determined based on the number of pulse outputs.

According to the third aspect of the present invention, the determination means calculates the waveform pulse width by the pulse width processing section from the tightening torque value obtained by the torque signal processing section, and determines the pulse wrench of the pulse wrench based on the pulse width. Deterioration is determined.

According to the fourth aspect of the present invention, the continuous torque generated by the power source is converted into an intermittent pulse output by the pulse generator while the tip is engaged with the screw member. Is tightened. At this time, the tightening torque applied to the screw member is detected as a waveform by the detecting unit, and the determination unit determines deterioration of the pulse generating unit based on the detected tightening torque waveform.

According to the fifth aspect of the present invention, the deterioration of the pulse wrench is determined based on the number of times of pulse output obtained from the waveform of the tightening torque detected by the determining means.

According to the present invention, the deterioration of the pulse generator is determined based on the width of the tightening torque waveform detected by the determination means.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a pulse wrench deterioration judging device according to the present invention will be described in detail mainly with reference to FIG. In this embodiment, an oil pulse wrench will be described as a pulse wrench, but the present invention is not limited to this embodiment. In the drawings, the same reference numerals denote the same or corresponding parts. The degradation determination device for a pulse wrench of the present invention generally includes a power source 10 that is driven to rotate continuously, a pulse generator 11 that converts a continuous rotation force from the power source 10 into an intermittent pulse output,
Pulse generating unit 1 engaged with a screw member (not shown)
A pulse wrench 1 having a tip portion 12 for tightening a screw member by an intermittent pulse output is a deterioration determining device for detecting a tightening torque to a screw member due to an intermittent pulse output of a pulse generator 11 as a waveform. Detecting means 2
And a torque signal processing unit 30 for calculating a tightening torque value from the tightening torque signal obtained by the detection unit 2. The waveform of the fluctuating tightening torque value obtained by the torque signal processing unit 30 is Determining means 3 for determining the deterioration of the pulse wrench based on the determination. The judging means 3 further includes a pulse interval time processing section 31 for calculating a pulse interval time from the tightening torque value obtained by the torque signal processing section 30. The deterioration of the pulse wrench 1 is determined on the basis of the number of pulse outputs obtained from the obtained pulse interval time. Also, determination means 3
Further includes a pulse width processing unit 32 for calculating the pulse width of the waveform from the tightening torque value obtained by the torque signal processing unit 30. The pulse width processing unit 32
Is to judge the deterioration of the pulse wrench 1 on the basis of the pulse width obtained by the above.

First, a description will be given of an oil pulse wrench 1 in which deterioration is determined in this embodiment. In this embodiment, the power source 10 comprises an air motor that is continuously driven to rotate by being supplied with compressed air. As shown in FIG. 16 is connected. The power source 10 is not limited to an air motor, but may be a motor driven by electricity. The output shaft 10a of the power source 10 is connected to the pulse generator 11, and the continuous torque is transmitted to the pulse generator 11.

The pulse generator 11 receives the continuous rotational force from the power source 10 and rapidly increases the pressure of the oil filled therein, thereby converting the pulse into an intermittent pulse (pulsation) and outputting the pulse output. This intermittent pulse output is transmitted to the tip 12.

When the screw member is a bolt (not shown), the distal end portion 12 has a socket 12a at the distal end to be engaged with the head of the bolt.
The bolt is tightened by receiving the intermittent pulse output by 1.

In the pulse wrench 1 configured as described above, during use, the pulse generating unit 11 is deteriorated due to leakage of the oil filled therein and reduction in the case of an oil pulse wrench. Becomes In addition,
Even in the case of an impact wrench, the pulse generator 11
As a result, the hammer mechanism for generating the impact deteriorates due to wear and the like.

FIGS. 3 and 4 show an oil pulse wrench 1.
In order to make the pulse generating section 11 of the above-mentioned type artificially deteriorated, the cut torque when the oil filled in each of the pulse generating sections 11 is removed from a normal state with a different type of pulse wrench is reached. 6 is a graph for each pressure condition, showing the number of pulses and the width (time) of the pulse waveform detected up to this point. 5 and 6 show the results of detecting the pulse waveform until the cut torque is reached in the normal state (FIG. 5) and the deteriorated state (FIG. 6) of the pulse generator 11. .

As shown in FIGS. 3 and 4, as the pulse generator 11 deteriorates, the number of pulses indicated by the broken line increases and the pulse width indicated by the solid line decreases. Will be done. Then, comparing the normal state (FIG. 5) and the deteriorated state (FIG. 6),
In the state where the pulse generation unit is deteriorated (FIG. 6), the number of pulses until the cut torque CT is increased, and the width (time) t2 of each pulse of the detected pulse waveform is increased.
Is narrower (shorter) than the width t1 of each pulse in the normal state. Therefore, in the present invention, the pulse wrench 1 is determined based on at least one of the pulse count and the pulse width.
Is determined.

In the case of this embodiment, the detecting means 2 is constituted by a torque transducer having a strain gauge provided at the distal end portion 12, and the distortion generated at the distal end portion when the screw member is tightened by intermittent pulse output. Is output to the determination means as a tightening torque signal.

The determining means 3 includes a torque signal processing section 30 for calculating a tightening torque value from the tightening torque signal output from the detecting means 2 and a pulse interval time based on the tightening torque value obtained by the torque signal processing section 30. And a pulse width processing unit 32 for calculating the pulse width (time) of the waveform from the tightening torque value obtained by the torque signal processing unit 30.
And a torque signal processing unit 30 and a pulse interval time processing unit 31
A tightening torque value calculated by the pulse width processing unit 32, a pulse interval time, and a comprehensive determination processing unit 33 that comprehensively determines the control of the pulse wrench 1 based on the pulse width time.
And Further, the determination unit 3 includes a display unit 34 that displays a result determined by the comprehensive determination processing unit 33,
The power source 10 and the compressed air supply 16
And an output unit 35 connected to the shut-off device 15 interposed therebetween to output a control signal, and input means (not shown) for inputting various set values. From the input means, as various setting values, as shown in FIG. 5,
The cut torque value CT for stopping the tightening of the screw member, the upper and lower torque values Tmax and Tmin for determining whether the tightening torque at the end of the tightening is within a predetermined range, and for determining the deterioration of the pulse generator 11. , The number of pulses having a predetermined range (upper limit and lower limit), the respective thresholds of the pulse width (time), and the like are input, and these various set values are stored in the comprehensive judgment processing unit 33.

The torque signal processing section 30 includes a low-pass filter for removing noise from the tightening torque signal output from the detecting means 2 and an amplifier for amplifying the tightening torque signal from which the noise has been removed ( (Not shown), a tightening torque signal that changes in a pulse-like waveform is digitized, and this tightening torque value is converted into a pulse interval time processing unit 31, a pulse width processing unit 32, and a comprehensive judgment processing unit 33.
Respectively. In the pulse interval time processing unit 31,
The pulse interval time is obtained from the interval time of the received tightening torque value that fluctuates in a pulse shape. The pulse width processing unit 32 determines the pulse width of the waveform from the received tightening torque value that fluctuates in a pulse shape. The overall determination processing unit 33 compares the tightening torque value output from the torque signal processing unit 30 with the set cut torque value CT, and when the tightening torque value reaches the cut torque value CT, tightens the screw member. Output unit 35 to stop
A shut-off signal is output to the shut-off device 15 via the. Also,
The comprehensive judgment processing unit 33 determines whether the tightening torque value at the time of interruption output from the torque signal processing unit 30 falls within a predetermined range (tolerance) between the set upper limit torque value Tmax and the set lower limit torque value Tmin. That is, it is determined whether the screw member has been properly tightened. Further, the comprehensive judgment processing unit 33 calculates the number of pulses per unit time from the pulse interval time obtained by the pulse interval time processing unit 31,
Alternatively, the number of pulses from the start of tightening to reaching the cut torque CT is calculated, and at least one of the number of pulses and the pulse width obtained by the pulse width processing unit 32 is within a predetermined range of the threshold value. It is determined that the pulse generator 11 is degraded when it is not within this range.

In the display means 34, the input various set values, the tightening torque value obtained by the torque signal processing unit 30, the determination result as to whether the screw member is tightened normally, and the pulse interval time processing unit 31 determine Number of pulses,
The pulse width determined by the pulse width processing unit 32, the deterioration determination result of the pulse wrench 1 determined by the comprehensive determination processing unit 33, and the like are displayed.

The pulse generator 1 is controlled by the overall judgment processor 33.
If it is determined that 1 is deteriorated, the display means 34
May simply be configured to give the notice to
The output unit 35 may output a signal from the output unit 35 to the shutoff device 15 so that the next screw member cannot be tightened until the reset operation is performed.

Next, a method of determining deterioration of a pulse wrench according to the present invention will be described mainly with reference to FIG. 2 in the case where a deterioration determining apparatus configured as described above is used. The method for determining deterioration of the pulse wrench 1 of the present invention generally includes a power source 10 that is driven to rotate continuously, a pulse generator 11 that converts a continuous rotational force from the power source 10 into an intermittent pulse output,
This is a method for determining deterioration of the pulse wrench 1 having a tip portion 12 engaged with a screw member and tightening the screw member by an intermittent pulse output of the pulse generator 11, wherein the screw member is tightened by an intermittent pulse output. At this time, the intermittent tightening torque is detected as a waveform, and the deterioration of the pulse wrench 1 is determined based on the waveform of the tightening torque. Then, deterioration of the pulse wrench is determined based on the number of times of pulse output obtained from the waveform of the detected tightening torque. Further, the deterioration of the pulse generator is determined based on the width of the detected tightening torque waveform.

First, prior to tightening the screw member using the pulse wrench 1, a cut torque value CT for stopping the tightening of the screw member is to determine whether the tightening torque at the time of the stop is within a predetermined range. Tightening torques such as upper and lower torque values Tmax and Tmin are set (S1),
Next, ranges having predetermined upper and lower limits of the number of pulses and the pulse width (time) for determining the deterioration of the pulse generator 11 are set (S2), and these set values are input by input means (not shown). Then, it is stored in the comprehensive judgment processing unit 33.

Next, the socket 12a of the distal end portion 12 is engaged with the screw member, and a command to start tightening is input from the input means to the comprehensive judgment processing section 33. From the overall judgment processing unit 33, the tightening start signal is output from the shutoff device 15 via the output unit 35.
The compressed air is supplied to the air motor 10 from the compressed air supply source 16. Thus, the air motor 10 is continuously driven to rotate, and the pulse generated by the pulse generator 11 is rapidly increased by receiving the continuous rotational force, so that an intermittent pulse output is generated. The distal end portion 12 is intermittently driven to rotate by an appropriate pulse output, and tightening to the screw member is started (S3). The fastening start signal may be automatically output by detecting that the socket 12a of the distal end portion 12 is engaged with the screw member.

When the tightening is started, the tightening torque signal which fluctuates in a pulse form output from the detecting means 2 provided at the tip 12 is transmitted to the torque signal processing unit 30 of the determining means 3.
Calculates the tightening torque value and outputs it to the pulse interval time processing unit 31, the pulse width processing unit 32, and the comprehensive judgment processing unit 33. Then, the determined tightening torque value is recorded by the comprehensive determination processing unit 33 (S
4). The pulse interval time processing unit 31 determines the pulse interval time from the determined waveform of the tightening torque value that fluctuates in a pulse shape.
3 is recorded (S5). In the pulse width processing section 32, a pulse width (time) is obtained from the obtained waveform of the tightening torque value that fluctuates in a pulse shape, and this pulse width is recorded by the comprehensive judgment processing section 33 (S6).

The overall judgment processing unit 33 compares the tightening torque value output from the torque signal processing unit 30 with the set cut torque value CT to determine whether the tightening torque value has reached the cut torque value CT. (S7). If it is determined that the cut torque CT has not been reached (NO in S7), the tightening is continued until the cut torque CT is reached, the tightening torque value is recorded (S4), and the pulse interval time is recorded (S5). ) And recording of pulse width (S
Step 6) is repeated.

When it is determined that the tightening torque value has reached the cut torque value CT (YES in S7),
The shut-off device 1 from the comprehensive judgment processing unit 33 via the output unit 35
5 is output (S8), the tightening of the screw member is stopped, and the tightening torque value at this time is displayed on the display unit 34 (S9). Then, the comprehensive determination processing unit 33 calculates the number of pulses per unit time from the pulse interval time, or the number of pulses from the start of tightening to the time when the cut torque value CT is reached (S10).

Thereafter, (S
It is determined whether the number of pulses obtained in 10) is within the range of the number of pulses set in (S2) (S11), and the pulse width recorded in (6) is the pulse set in (S2). It is determined whether it is within the range of the width (S12), and the deterioration of the pulse wrench 1 is determined. The deterioration of the pulse wrench 1 is caused when the calculated pulse number is not within the set pulse number range (NO in S11), or when the recorded pulse width is not within the set pulse width range ( If NO in S12), if either the calculated pulse number or the recorded pulse width is not within the set pulse number or pulse width range, both the calculated pulse number and the recorded pulse width Is not within the set pulse number or pulse width range.

When it is determined that the pulse wrench 1 has deteriorated when the calculated number of pulses is not within the range of the set number of pulses, a signal for immediately informing of the deterioration is sent from the comprehensive judgment processing unit 33. Output to the display unit 34 (S1
3) The determination of whether the recorded pulse width is within the set threshold (S12) is omitted.

When it is determined that the pulse wrench 1 has deteriorated when the recorded pulse width is not within the set pulse width range, the number of pulses is calculated (S10) and the number of pulses is set. The determination as to whether the number of pulses is within the range of the number of pulses (S11) is omitted, and after determining whether the pulse width is within the set range (S12), a signal for notifying deterioration is immediately sent from the comprehensive determination processing unit 33 to the display unit 34. (S13).

If it is determined that the pulse wrench 1 has deteriorated when either the calculated pulse number or the recorded pulse width is not within the set pulse number or pulse width range, the pulse number Calculation (S10) and determination whether the number of pulses is within a set range (S1)
If 1) is performed and the number of pulses is not within the set range, a signal for immediately informing of deterioration is output from the comprehensive determination processing unit 33 to the display unit 34 without performing determination of the pulse width (S12). (S13). If the number of pulses is within the set range, then the pulse width is determined (S12). If the pulse width is not within the set range, a signal for notifying the deterioration is determined by the comprehensive judgment processing unit 33. Is output to the display unit 34 (S13). In this embodiment, the case where the determination of the number of pulses (S11) is followed by the determination of the pulse width (S12) has been described. However, the present invention is not limited to this order. Next, the number of pulses can be determined (S11).

If it is determined that the pulse wrench 1 has deteriorated when both the calculated pulse number and the recorded pulse width are not within the set pulse number and pulse width ranges, the pulse number calculation is performed. (S10) and whether the number of pulses is within the set range is determined (S11). If the number of pulses is not within the set range, the pulse width is determined (S12) and the pulse width is set. If not, the signal for notifying the deterioration is output from the comprehensive judgment processing unit 33 to the display unit 34 (S13). If the number of pulses is within the set range, the determination of the pulse width (S12) is omitted.

It is determined that the pulse generator 11 of the pulse wrench 1 has deteriorated, and after notifying the deterioration (after S13), usually, the tightening of the screw member is temporarily terminated to temporarily stop the pulse wrench 1. The deterioration is repaired, that is, the oil is filled into the pulse generator 11 and the like. However, in the initial stage of deterioration or the like, as shown by a chain line in FIG. 2, it is also possible to notify the deterioration (S13) and to continue the tightening of the screw member.

If it is determined that the pulse wrench 1 has not deteriorated, or if the tightening of the screw member is to be continued, it is determined whether the tightening of the screw member is to be terminated (S1).
4) If not terminated (NO in S14)
In the case where the above (S3) and subsequent steps are repeated to terminate the tightening of the screw member (NO in S14)
Becomes END.

[0051]

According to the first aspect of the present invention, a detecting means for detecting a tightening torque to a screw member due to an intermittent pulse output of the pulse generating section as a waveform, and a detecting means for detecting a tightening torque signal obtained by the detecting means. A torque signal processing unit for calculating and processing a tightening torque value; and a determination unit for determining deterioration of the pulse wrench based on a waveform of the fluctuating tightening torque value obtained by the torque signal processing unit. Thus, it is possible to provide a pulse wrench deterioration determination device that can easily determine the deterioration of the pulse wrench with a simple configuration, and thus improve the accuracy of the substantial tightening force of the screw member by the pulse wrench. be able to.

According to a second aspect of the present invention, in the first aspect of the present invention, the determining means further includes a pulse interval time processing section for calculating a pulse interval time from the tightening torque value obtained by the torque signal processing section. The pulse wrench is determined based on the number of pulse outputs determined from the pulse interval time determined by the pulse interval time processing unit. In addition, it is possible to provide a pulse wrench deterioration determination device that can be easily determined.

According to a third aspect of the present invention, in the first or second aspect, the determining means further calculates a pulse width of the waveform from the tightening torque value obtained by the torque signal processing section. It has a processing unit, and determines the deterioration of the pulse wrench based on the pulse width obtained by the pulse width processing unit, so that the deterioration of the pulse wrench can be determined accurately and easily. It is possible to provide a pulse wrench deterioration determination device that can perform the above.

According to the fourth aspect of the invention, when the screw member is tightened by the intermittent pulse output, the intermittent tightening torque is detected as a waveform, and the pulse wrench of the pulse wrench is detected based on the waveform of the tightening torque. By determining the deterioration, it is possible to provide a deterioration determination determination of the pulse wrench that can easily determine the deterioration of the pulse wrench with a simple configuration. The accuracy of the tightening force can be improved.

According to the fifth aspect of the present invention, in the fourth aspect of the invention, the deterioration of the pulse wrench is determined based on the number of times of the pulse output obtained from the waveform of the detected tightening torque. It is possible to provide a pulse wrench deterioration determination method capable of accurately and easily determining the deterioration of the pulse wrench.

According to the invention of claim 6, in the invention of claim 4 or 5, the deterioration of the pulse generator is determined based on the width of the waveform of the detected tightening torque. Can be provided accurately and easily.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of the configuration of a pulse wrench deterioration determination device of the present invention.

FIG. 2 is a flowchart showing an embodiment of a pulse wrench deterioration determination method according to the present invention.

FIG. 3 is a diagram showing a state in which the oil generated inside the pulse generator is removed from a normal state to detect a cut torque in order to make the pulse generator of the oil pulse wrench artificially deteriorated. It is a graph for each pressure condition which showed the number of times of the applied pulse and the width (time) of the pulse waveform.

FIG. 4 is a graph for each pressure condition showing the number of pulses detected and the width (time) of a pulse waveform until a cut torque is reached in a pulse wrench different from FIG. 3;

FIG. 5 is a graph showing a detected pulse waveform until the pulse generator reaches a cut torque in a normal state.

FIG. 6 is a graph showing a detected pulse waveform until a cut torque is reached in a state where the pulse generator is deteriorated.

[Description of sign]

 DESCRIPTION OF SYMBOLS 1 Pulse wrench 2 Detecting means 3 Judging means 10 Power source 11 Pulse generating part 12 Tip part 30 Torque signal processing part 31 Pulse interval time processing part 32 Pulse width processing part

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Eiichi Wada 3-55, Nishiiwata, Higashi-Osaka-shi, Osaka Inside Yokota Industries Co., Ltd. (72) Makoto Hasebe 3-5-Nishiiwata, Higashi-Osaka-shi, Osaka No. 55 Inside YOKOTA INDUSTRY CO., LTD.

Claims (6)

[Claims] 1. A power source that is driven to rotate continuously, a pulse generator that converts continuous torque from the power source into an intermittent pulse output, and an intermittent pulse output of the pulse generator that is engaged with a screw member. A pulse wrench having a tip for tightening a screw member, comprising: detecting means for detecting, as a waveform, a tightening torque applied to the screw member by an intermittent pulse output of a pulse generating unit; A torque signal processing unit for calculating a tightening torque value from the tightening torque signal obtained, and determining deterioration of the pulse wrench based on a waveform of the fluctuating tightening torque value obtained by the torque signal processing unit. And a means. 2. The determining means includes a pulse interval time processing section for calculating a pulse interval time from a tightening torque value obtained by the torque signal processing section, and a pulse obtained by the pulse interval time processing section. The pulse wrench deterioration determination device according to claim 1, wherein the deterioration of the pulse wrench is determined based on the number of times of pulse output obtained from the interval time. 3. The determining means has a pulse width processing section for calculating the pulse width of the waveform from the tightening torque value obtained by the torque signal processing section, and the pulse width obtained by the pulse width processing section. 3. The apparatus according to claim 1, wherein the deterioration of the pulse wrench is determined based on the width. 4. A power source that is driven to rotate continuously, a pulse generator that converts continuous torque from the power source into an intermittent pulse output, and an intermittent pulse output of the pulse generator that is engaged with a screw member. A method for determining deterioration of a pulse wrench having a tip portion for tightening a screw member, comprising: detecting an intermittent tightening torque as a waveform when the screw member is tightened by intermittent pulse output; A method for determining deterioration of the pulse wrench based on the waveform of the pulse wrench. 5. The method according to claim 4, wherein the deterioration of the pulse wrench is determined based on the number of times of pulse output obtained from the detected tightening torque waveform. 6. The pulse wrench according to claim 4, wherein the deterioration of the pulse generator is determined based on the width of the detected tightening torque waveform.