JPH08197445A - Fastening device - Google Patents

Abstract

PURPOSE: To reduce cost by reducing the number of part items and assembling man-hours and detect a turning angle with high accuracy in a fastening device for fastening a screw member to a fastened body. CONSTITUTION: A fastening device is constituted of an operating lever 63 with four strain gages fitted in specified positions, and a rotating fulcrum part 62 provided with an output shaft 73 and ratchet mechanism 72 for directly fastening a screw member such as a bolt. A gyroscope 79 for detecting a turning angle is provided on the turning body 71 of the rotating fulcrum part 62.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fastening device for fastening a threaded member to a fastened body.

[0002]

2. Description of the Related Art Conventionally, as a method for strictly controlling tightening torque when tightening a threaded member such as a bolt with a torque wrench as a tightening device, a torque measuring method,
There are a rotation angle method and a torque gradient method. The torque measuring method is a method of tightening while measuring the tightening torque, and the tightening is completed at a predetermined torque, and the rotation angle method is a method of tightening to a predetermined torque and then rotating it by a predetermined angle.

Further, the torque gradient method utilizes the fact that the screwing member and the tightening torque have a substantially proportional relationship up to a certain point, and simultaneously obtains the rotational angle and the torque corresponding to the angle while obtaining the torque from the two relationships. It is a method of tightening to the specified value. Therefore, FIG. 7 shows an overall plan view of the conventional torque wrench, and FIG. 8 shows a vertical cross-sectional view of the main part of the torque wrench of FIG. Torque wrench 1 shown in FIGS. 7 and 8
Reference numeral 1 denotes a rotating portion 1 which is attached to a bolt described later and is tightened.
2 and an operating lever 13 from the rotating portion 12 to the other end. The rotating portion 12 is provided with a ratchet 14 inside the rotating body 12a, and a ratchet claw 15 formed on the ratchet 14 engages with the ratchet 14. Ratchet claw 15
The switching lever 16 specifies the restriction direction. The output shaft 17 extends from the ratchet 14 from one surface of the rotating body 12a, and the output shaft 17 is connected to a socket mounted on a bolt described later. The connecting shaft 18 extends to the other surface of the rotating body 12a.

On the other hand, a rotation angle detector 19 is attached to the other surface of the rotating body 12a. The rotation angle detector 19
A rotary encoder 25 is provided between the first fixing portion 23 and the second fixing portion 24 in the first cover portion 20, the second cover portion 21, and the cap 22 attached to the rotating body 12 a. Are arranged. The first cover portion 20 is rotatable by the first fixing portion 23 and the bearing 26, and
In the fixed portion 23, the rotary shaft 28 is connected to the connecting shaft 18 via the flexible coupling 27.

The rotary shaft 28 is supported by bearings 29a and 29b in the rotary encoder 25. Further, the locking pin 30 is extended to the first fixing portion 23, and a metal plate member described later is attached thereto. A shaft 31 is formed on the second fixing portion 24, and is supported by the second cover portion 21 and the bearing 32 so as to be relatively rotatable.

On the other hand, the operating lever 13 has a wrench body 33.
And grip portion 34, and the wrench body 33
Is two strain gauges 35 on the left and right on the plane of FIG.
The handle part 36 to which a to 35d are attached is covered with a cover 37. Further, the wrench body 33 is provided with a switch section 38 having two switches 38a and 38b, and the cover 37 outputs signals from the strain gauges 35a to 35d and signals from the switches 38a and 38b to the plug 3.
It is led out to the outside by the cable 40 connected at 9.

Therefore, FIG. 9 shows a side view of the torque wrench of FIG. 7 in use. In FIG. 9, a torque wrench 1
The clip 41 is fixed to the locking pin 30 of No. 1, and one end of the metal plate member 42 is attached to the clip 41. A magnet 43 is attached to the other end of the clip 41 and is attracted to the fastened body 44. As a result, the first and second fixing parts 23 and 24 in the rotation angle detecting part 19 are fixed even when the torque wrench 11 is rotated.

Then, the output shaft 17 of the torque wrench 11 is attached to the socket 45, and the socket 45 is fastened to the fastened body 44.
It is fitted with a bolt 46 for tightening. In this state, as shown in FIG. 7, the grip portion 34 is gripped and rotated in the A ₁ direction (for example, ratchet engagement state) and the A ₂ direction (free state) to tighten the bolt.

At this time, the first and second fixing portions 23, 2
Although the metal plate member 42 and the magnet 43 are in a fixed state, the rotating shaft 28 in the rotary encoder 25 is rotated together with the rotating body 12a (the first and second cover portions 20 and 21). Thereby, the strain gauges 35a to 35
The tightening torque is detected by d, and the rotation angle detection unit 1
The rotary encoder 25 of 9 detects the rotation angle.

FIG. 10 shows a block diagram of the torque and rotation angle detection of FIG. In FIG. 10, the rotation detection signal from the rotary encoder 25 is sent to a CPU (central processing unit) 51. Further, the strain gauges 35a to 35d have resistance values that change due to extension and compression of the strain gauges 35a to 35d.
A bridge circuit (power supply voltage E ₀ ) 52 is formed by d, and the adjustment gauges Rd ₁ and Rd ₂ are appropriately connected to the strain gauges 35b and 35d.

A change in output from the bridge circuit 52 is input to the differential amplifier 53, and a change in output from the differential amplifier 53 is detected as a torque change. The output of the differential amplifier 53 is converted into a digital signal by an ADC (analog / digital converter) 54, and the CPU 5
Sent to 1. Therefore, the CPU 51 obtains the detected value of the torque from the strain gauges 35a to 35d and the detected value of the rotation angle from the rotary encoder 25, manages the tightening torque by the rotation angle method or the torque gradient method, and when the specified value is reached. The alarm sound is generated by the alarm 56 while being displayed on the display unit 55.

[0012]

However, as described above, it is necessary to provide the first and second fixing portions 23 and 24 in order to detect the rotation angle by the rotary encoder 25, which increases the number of parts and the number of assembling steps. Then, there is a problem that it is difficult to reduce the cost, size and weight of the device.

The first and second fixing portions 23 and 24 are separated from each other by a clip 41, a metal plate member 42, and a magnet 4.
3 must be fixed, the work procedure is complicated, and there is a problem in management and transportability, which reduces the workability of tightening.

Further, the first and second fixing portions 23 and 24
The magnet 43 is used to fix the magnet, and there is a problem that an accurate rotation angle cannot be detected in a place where the magnet 43 cannot be used (for example, a fastening operation of a plastic member).

Therefore, the present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to provide a fastening device for reducing the cost by reducing the number of parts and the number of assembling steps and for detecting the rotation angle with high accuracy. To aim.

[0016]

In order to solve the above-mentioned problems, according to a first aspect of the present invention, in a fastening device for rotating a screwing member to fasten it to an object to be fastened, the rotation of the screwing member is rotated. The fastening device is provided with a rotation angle detection means for detecting the rotation angle of the screwing member based on the magnitude of the rotation angular velocity in the space generated in accordance with the above.

According to a second aspect, the rotation angle detecting means according to the first aspect comprises a gyro.

[0018]

As described above, in the invention of claim 1 or 2,
A rotation angle detection means, which is appropriately configured by a gyro, detects the rotation angle of the screwing member from the magnitude of the rotation angular velocity in the space generated according to the rotation of the screwing member. As a result, it is possible to reduce the cost by reducing the number of parts and the number of assembling steps without requiring a fixing mechanism, and it is possible to detect the rotation angle with high accuracy because it is not affected by the surrounding conditions.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram showing the main part of a first embodiment of the present invention. Further, FIG. 2 shows an overall plan view of the torque wrench of FIG. FIG. 1A is a vertical sectional view.
(B) is a schematic diagram of a gyro.

A torque wrench 61 as a fastening device shown in FIGS. 1 and 2 is roughly divided into a rotation fulcrum portion 62 at one end and an operation lever 63 extending from the rotation fulcrum portion 62 to the other end. To be done. The rotation fulcrum portion 62 is provided with a ratchet mechanism 72 in the rotation body 71, and the ratchet mechanism 72 is provided.
An output shaft 73 is rotatably provided on the rotary shaft of and is extended to the outside from a cover 74 closing the rotary body 71. The ratchet mechanism 72 is composed of a ratchet wheel 75 having a saw tooth 75a having a tapered surface and a vertical surface, and a switching lever 76 having a claw that engages with the saw tooth.

A rotation detector 77, which is a rotation angle detector, is mounted on the rotary body 71. The rotation detector 77 has a vibration gyro 79 provided in an outer cover 78. In the gyro 79, as shown in FIG. 1B, a triangular prism-shaped piezoelectric vibrator 81 is erected on a base 80, and one excitation piezoelectric element 82 and two detection piezoelectric elements 83 are provided on each side surface. , 84 are attached.

The gyro 79 as described above has two detecting piezoelectric elements 8 depending on the rotating directions B ₁ and B ₂ of the rotating body 71.
3 and 84 receive the rotational angular velocity in space, and the output changes in accordance with the magnitude of the rotational angular velocity to detect the rotational angle. For example, when a predetermined excitation voltage is applied to the excitation piezoelectric element 82 and the piezoelectric vibrator 81 is excited, when the rotating body 71 does not rotate, the output voltages of the left and right detection piezoelectric elements 83 and 84 have the same level. Is.
Then, when the rotating body 71 rotates in the B ₁ direction, the detecting piezoelectric element 83 receives a stronger vibration than the other due to the moment.
On the contrary, the vibration applied to the detection piezoelectric element 84 becomes weak. Therefore, when rotating in the B ₂ direction, the piezoelectric elements 8 for detection are similarly detected.
A voltage corresponding to the difference between the increase and the decrease of 3,84 is output, and the rotation angle is detected according to the output voltage.

In this embodiment, as an example, a vibration type
The case where a gyro 79 is used is shown.
A gyro, an optical fiber gyro, etc. may be used.
You may use the gyro etc. provided with a rotating body. Meanwhile, the operation
The lever 63 is integrated with the rotating body 71 of the rotating fulcrum portion 62.
The handle 91 is extended, and the tip of the handle 91 serves as the grip 92.
It The handle 91 is covered with an operation cover 93,
The 71 side and the rubber member 94 are interposed. On the handle 91
The first position d from the center C of the force shaft 73₁How to rotate
Strain gauges (resistance G₁, G₂) 9
5, 96 are attached, and the second position portion d from the center C₂
(Eg 2d₁= D₂) Strokes on both sides
Rain gauge (resistance G ₃, G_Four) 97, 98 are attached
Be killed.

A processing unit 99 is provided in the operation cover 93.
(Described later) is provided, and the operation panel 100 is exposed. A display unit 101, an alarm 102, and various switches 103 are arranged on the operation panel 100. Further, the side of the operation cover 93 is provided with a connector plug 10 from the outside
4 is provided with a connector 105 for external connection (see FIG. 3).

Next, FIG. 3 shows a side view of the torque wrench of FIG. 1 in use. As shown in FIG.
The output shaft 73 of the torque wrench 61 is the one that is tightened by the bolt 112 that is a screwing member.
It is attached to one end of 13, and the other end of the socket 113 is fitted to the head of the bolt 112.

Such a torque wrench 61 manages the tightening torque by the above-described rotation angle method (or torque gradient method), and the specified values of the torque and the rotation angle are preset by the switches 103, and The switching lever 76 switches the tightening direction. Then, when the bolt 112 is tightened by rotating it in the front and rear directions (B ₁ and B ₂ directions in FIG. 2) in FIG. 3, the strain gauge 95
˜98 to detect the tightening torque, and the gyro 79 to detect the rotation angle. The details will be described below.

FIG. 4 shows the torque and rotation angle detection of FIG.
The block block diagram is shown. FIG. 4 shows the processing of the processing unit 99 described above.
It is a block diagram showing four strain gauges 9
5-98 resistor G₁~ G_FourWith bridge circuit (power supply voltage
E₀) 121 is formed, and strain gauge 9
7,98 resistor G₁~ G_FourAdjustment resistor R
d ₁, Rd₂(The resistance does not change due to the bending of the handle 91)
Are connected in series. Output end of this bridge circuit 121
The output voltage is input to the differential amplifier 122 from the children A and B,
The output voltage of the differential amplifier 122 is digital by the ADC 123.
It is converted into a value and sent to the CPU 124. This brit
Circuit 121, differential amplifier 122, ADC 123
It becomes a detection means.

On the other hand, in detecting the rotation angle, the output signal (voltage value) from the gyro 79 is input to the zero shift unit 125, and the output from the zero shift unit 125 is input to the first and second comparators 126 and 127, respectively. At the same time, it is input to the absolute amplifier 128. Zero shift unit 12
5 shifts the output signal (voltage value) of the gyro 79 to be 0V reference, and the shifted detection voltage is sent to the V / F (voltage-frequency converter) 129 via the absolute value amplifier 128. It The V / F 129 generates a predetermined number of pulses for a predetermined voltage, and the pulses are sent to the gate unit 130.

In addition, the first and second comparators 12
6, 127 compares the output signal from the gyro 79 of the zero shift unit 125 with each reference value and compares it with the gate unit 130.
And to the positive / negative determination unit 131. In the gate unit 130, the pulse from the V / F 129 is selected and selected by the outputs of the first and second comparators 126 and 127, and the counter 1 is selected.
32. The counter 132 adds or subtracts the pulse from the gate unit 130 according to the signal from the positive / negative determination unit 131, and sends the count value to the CPU 124.

The CPU 124 is set with the specified torque value and the set rotation angle value as described above, and the bridge circuit 12
Based on the torque detection signal from 1 and the count value from the counter 132, a predetermined display is performed on the display unit 101 and the alarm 102 is sounded.

Here, the torque generated by the bridge circuit 121
The detection will be described. The bridge circuit 121 is G₁・ G
_Four・ Rd₂= G₂・ G₃・ Rd₁Is in equilibrium when
Adjustment resistor Rd during initial setting₁, Rd₂Can be adjusted
And strain gauge G₃, G_FourThe sensitivity of the
Set in equilibrium. In torque detection, d₂/ D₁= K
(K> 1), and the first position portion d₁The moment at m
₁, The second position part d₂The moment at m₂Then,
The torque T is T = (kd₁m₁-D₁m₂) / (Kd₁-D₁) = (Km₁-M₂) / (K-1) ... (1), and (k-1) T = km₁m₂Therefore, the
Strain gauge G at position 1₁, G₂Second sensitivity
Strain gauge G at the position of₃, G_FourK times the sensitivity of
There must be. Adjustment resistor Rd₁, Rd₂With
Kiha (G₃+ Rd ₁) Resistance is G₃K times, and (G_Four
+ Rd₂) Resistance is G_FourAdjustment resistor R to be k times
d₁, Rd₂The resistance value of is set.

Therefore, when 2d ₁ = d ₂ , the moments of the strain gauges G ₁ and G ₂ are m ₁ and the moments of the strain gauges G ₃ and G ₄ are m ₂ , so the torque T at the center of rotation is , T = (2dm ₁ −d ₁ m ₂ ) / (2d ₁ −d ₁ ) = 2m ₁ −m ₂ (2) That is, the torque T from those obtained by doubling the moment of strain gauges G _1, G ₂ moiety, is calculated by subtracting the moment of the strain gauge G _3, G ₄ moieties.

Therefore, the bridge circuit 121 is connected to the first position.
Strain gauge G that extends the table ₁And the second position
Strain gauge G to compress_FourWith the opposite side as the first position
Strain gauge G that compresses the table₂And the second position
Expanding strain gauge G ₃As opposite sides
Thus, the calculation can be completed in the bridge circuit 121.
Becomes This calculation result is taken by the differential amplifier 122.
And is sent to the CPU 124 via the ADC 123.
It is what is done.

Next, the detection of the rotation angle will be described by showing a concrete example. The gyro 79 outputs a voltage according to the moment (rotational angular velocity) as described above, and outputs, for example, 2.5 V when the moment is not applied, and with this as a reference, the angular velocity is 1 ° / sec. To 10
Increase or decrease mV. For example, when rotated by 80 ° / sec in the B ₁ direction (assumed to be the plus direction) in FIG. 1B, 3.3 V is output, and 40 ° / in the B ₂ direction (minus direction).
Output 2.1V when rotated for sec. Zero shift part 1
25 is 2.5 with respect to the output voltage from the gyro 79.
The V reference is shifted to the 0V reference, and 0.8V is applied to the output voltage 3.3V from the gyro 79 in the above example.
(2.5V is subtracted), and the output voltage is 2.1V minus (-) 0.4V.

The absolute value amplifier 128 includes a zero shift unit 12
The absolute value of the output voltage from 5 is output, and 0.8V
To 0.8V, and to minus (-) 0.4V, plus (+) 0.4V. V / F129
Output a pulse of 1 Hz with respect to an input of 10 mV, and output voltage 0.
One pulse is output to the gate unit 130 every 1/80 sec with respect to 8V.

The gyro 79 outputs an offset voltage even when the angular velocity is zero, and this offset voltage may cause unnecessary pulses from the V / F 129. Therefore, for example, the pulse generated at the angular velocity of 0.5 ° / sec or less in the gyro 79 is deleted to avoid the influence of the offset voltage. For that purpose, the outputs from the first and second comparators 126 and 127 are input to the gate unit 130.

For example, in the above example, if the reference voltage of the first comparator 126 is +5 mV and the reference voltage of the second comparator 127 is -5 mV, both are high level "H" when the input is above the reference voltage. Gate signal 13 "
When the input voltage is equal to or lower than the reference voltage, a low level “L” signal is output to the gate unit 130. Then, in the gate unit 130, the first and second comparators 1
When one of the output signals from 26 and 127 is "H" and the other is "L", the pulse from the V / F 129 is deleted so that it is not output to the counter 132. That is, the first and second comparators 12
When the outputs of 6 and 127 are both “L” or “H”, the pulse from the V / F 129 from the gate unit 150 is used as the normal output voltage instead of the offset voltage.
Output to.

Therefore, when the output voltage from the gyro 79 is, for example, 2.502 V (the output voltage from the zero shift section 125 is 2 mV), one pulse is input to the gate section 130 from the V / F 129 every 5 seconds. However, since the output from the first comparator 126 is “L” and the output from the second comparator 127 is “H”, the pulse is deleted from the gate unit 130 and is not output. .

Further, the first and second comparators 12
Based on the outputs (“L” or “H”) of 6, 127, the rotation direction is determined by the positive / negative determination unit 131 and output to the counter 132. For example, the output voltage from the gyro 79 is 3.3.
When the output voltage from the zero shift unit 125 is 0.8V at V, the outputs of the first and second comparators 126 and 127 both become "H" and it is determined that the forward rotation is performed, and the counter 132 outputs from the gate unit 130. Add pulses.
When the output voltage from the gyro 79 is 2.1V and the output voltage from the zero shift unit 125 is -0.4V, the outputs of the first and second comparators 126 and 127 both become "L" and rotate in the reverse direction. It is determined that the counter 13
At 2, the pulse from the gate unit 130 is subtracted.

In the CPU 124, assuming that the tightening direction of the bolt 112 is forward rotation (may be reverse rotation), the torque from the bridge circuit 121 is obtained from the count value from the counter 132 corresponding to the rotation direction only during forward rotation. It is determined whether or not the rotation has occurred, the addition is performed, and the case of reverse rotation is ignored, so that the rotation angle corresponding to the count value is detected by the count value only in the tightening direction.

By the way, when the bolt 112 is tightened, a dead angle of the tightening angle is generated due to a spring back, a fitting backlash (play) with the socket 113, or the like. Therefore, in order to eliminate this dead angle, the CPU 124 refers to the torque value from the bridge circuit 121 when the count value of the counter 132 changes to monitor whether or not the torque is generated.

For example, when the torque value is 80% or more of the maximum torque measured during the tightening work, the counter 1
By determining that the change in the count value from 32 is effective for detecting the rotation angle, the above dead angle can be prevented. Therefore, FIG. 5 shows an operation flowchart of the rotation detection of FIG. In the present embodiment, it is assumed that the tightening work is performed by the above-described rotation angle method, and the tightening is performed until a predetermined torque value in the middle is reached, and after the predetermined torque value is reached, the tightening is performed at a predetermined rotation angle. As a predetermined torque value and a predetermined rotation angle are preset.

FIG. 5 is an operation flow chart of the CPU 124. When tightening is started, it is judged whether or not the tightening is the set torque value (step (S)).
1) When the set torque value is reached, the alarm 102 is activated (S2). Then, the tightening at the rotation angle is started, and the count value from the counter 132 and the torque value from the bridge circuit 121 are monitored (S3).

Then, it is judged whether the rotating direction of the rotating body 71 is the tightening direction, that is, whether it is the effective rotating direction or not, based on whether the torque is generated from the bridge circuit 121 (S).
4) If the rotation direction is not valid, the count is invalidated (S5). When the rotation direction is valid, it is determined whether or not the generated torque value is equal to or more than a set value (80% or more of the maximum torque measured during the tightening work) (S
6) If it is 80% or less, the springback or the fitting is loose and the count is invalid (S7).

When the torque value is 80% or more, the count value from the counter 132 is added, and the rotation angle corresponding to the added count value is displayed on the display unit 101 (S).
9). It is determined whether or not the tightening progresses and the added set value, that is, the rotation angle at which the tightening is completed, is reached (S10), and if not reached, S4 and subsequent steps are repeated (S4 to S10).

When the rotation angle at which the tightening is completed is reached, the alarm 102 is sounded and the tightening work is ended. (S11). in this way,
By using the gyro 79 for detecting the rotation angle, the number of parts and the number of assembling steps can be reduced, and the cost can be reduced, and the size and the weight can be reduced. Further, since it is not necessary to fix the torque wrench 61 to any one, the work procedure can be simplified, management, transportability and workability can be improved, and the rotation angle can be detected with high accuracy. It is possible. Further, as is clear from comparison between FIG. 4 and FIG. 10, the bridge circuit 121, the differential amplifier 122, the ADC 123, the CPU 1
24, the display unit 101, and the alarm 102 can be shared, and the cost can be reduced.

Next, FIG. 6 shows a block diagram of a second embodiment of the present invention. In FIG. 6, the mechanical configuration of the torque wrench 61 is the same as in FIGS. 1 and 2, and in the processing unit 99 _A , the output from the gyro 79 is C through the ADC 141.
It is sent to PU124 _A. The CPU 124 _A includes first and second counters 142 and 143. For example, the first counter 142 is the operating lever 6 of the torque wrench 61.
The second counter 1 counts according to the rotation of 3 (± directions).
43 counts according to the rotation angle of the bolt 112.

Although the gyro 79 is the same as that of the first embodiment, a more detailed specification will be described. The output voltage at zero angular velocity (0 deg / sec) is 2.5 V (reference voltage), and the maximum angular velocity is The output is ± 90 deg / sec, the maximum output is ± 2 V with respect to the standard output 2.5 V, the output per angular velocity is 22.2 mV ± 1.4 mV / deg / sec, and the angular resolution is 0.1 deg / sec.

Further, the AD for the output of the gyro 79
The output of C141 is used as the ADC value, and the voltage at reset is used as the reference ADC value. For example, angular velocity of 0.05 deg / s
The ADC value of ec is 1. Here, the operation condition of the processing unit 99 is that the count is integrated as + when the turning direction of the operation lever 63 of the torque wrench 61 is clockwise and-when the turning direction is counterclockwise. In addition, the ADC value is ± for noise removal.
When the speed is 5 or less (the angular velocity is 0.25 deg / sec or less), the integration is not performed, it is determined that the rotation is stopped, and the integration is performed when the ADC value exceeds ± 6. Furthermore, the ADC value is 5 or less and 6
When the above is mixed, alarm 1 is set as a low speed alarm.
02 is sounded, and when the ADC value is 2000 or more, the alarm 102 is sounded as a high speed alarm.

When the ADC value 22.2 is integrated 1000 times, it is assumed that it has advanced by 1 deg (the ADC value 222.
May be integrated 100 times and the ADC value 2220 may be integrated 10 times). Further, the count in the second counter 143 is integrated, for example, when the torque during tightening is 80% or more of the maximum torque, as in the first embodiment, and when the torque is 80% or less of the maximum torque, or the operating lever 63. When the direction of is opposite to the tightening direction (the first counter 142 subtracts), it is not integrated and remains as it is.

Therefore, when tightening the torque wrench 61, the condition is first set. Specifically, the tightening direction is set to right rotation or left rotation, and the torque T _{i at} an angle of zero is set.
The setting and the rotation angle θ _t are set from the torque T _i , and when the tightening is started, the count value of the first and second counters 142 and 143 and the torque value are reset and initialized.

When the torque wrench 61 rotates and the rotational angular velocity is less than the absolute value 5 ADC value, it is determined that the torque wrench 61 is not rotating. ADC 141 by A 141
Add the DC value (subtract when tightening direction is opposite). For example, when tightening 40 deg to the right and returning 30 deg to the left and then further tightening to the right, the first counter 142 counts a count value of 10 deg.

When the torque value of the second counter 143 is rotated by the torque wrench 61 in the tightening direction and the torque value is 80% or more of the maximum torque measured up to that point, the second counter 143 is AD.
The C value is integrated and ignored if it is 80% or less. For example, as described above, when rotating by 40 deg in the tightening direction, returning by 30 deg, and further tightened by 15 deg, when the torque values at the time of tightening are all 80% or more of the maximum torque before that, the ADC value of 55 deg becomes It will be accumulated. By the way, the first counter 142 has 25
ADC values for deg are integrated.

On the other hand, CPU 124 _A is, ADC value of the first counter 142, ADC value of the second counter 143 collected (angle 1deg min) and torque value at that time, the memory (Figure provided in the relevant CPU 124 _A with angle (Not shown). That is, the tightening transition data is collected.

Then, when the value of the tightening torque reaches the set value T _i , the CPU 124 _A causes the alarm 102 to sound, displays on the display unit 101, etc., and resets the second counter 143. Thereafter, as described with reference to FIG. 5, the rotation angle of further tightening is monitored by the second counter 143, and when the rotation angle reaches θ _t , the alarm 102 is sounded and tightened with a desired torque. To notify that the process has been completed.

As described above, by providing the first and second counters 142 and 143 in the CPU 124 _A , the circuit can be simplified and the cost can be reduced. The present invention can be applied not only to the rotation angle method described in the above embodiment but also to the torque gradient method in monitoring torque during tightening.

[0057]

As described above, according to the first or second aspect of the invention, the rotation angle detecting means, which is appropriately constituted by a gyro, is screwed from the magnitude of the rotation angular velocity in the space generated according to the rotation of the screwing member. By detecting the rotation angle of the member, it is possible to reduce the number of parts and the number of assembling steps without using a fixing mechanism, and it is possible to detect the rotation angle with high accuracy because the surrounding conditions are not affected.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a main part of a first embodiment of the present invention.

FIG. 2 is a plan view of the torque wrench shown in FIG.

FIG. 3 is a side view of the torque wrench of FIG. 1 in use.

4 is a block configuration diagram of torque and rotation angle detection of FIG. 1. FIG.

5 is an operation flowchart of rotation detection of FIG.

FIG. 6 is a block configuration diagram of a second embodiment of the present invention.

FIG. 7 is an overall plan view of a conventional torque wrench.

8 is a vertical cross-sectional view of the main part of the torque wrench of FIG.

9 is a side view of the torque wrench of FIG. 7 in use.

10 is a block configuration diagram of torque and rotation angle detection of FIG. 7. FIG.

[Explanation of reference numerals] 61 torque wrench 62 rotation fulcrum 63 operation lever 71 rotation body 72 ratchet mechanism 73 output shaft 75 ratchet wheel 76 switching lever 77 rotation detection unit 79 gyro 91 handle 92 gripping portion 95 to 98 strain gauge 99, 99 _A processing unit 100 operation panel 101 display unit 102 alarm 111 fastened object 112 bolt 113 socket 121 bridge circuit 122 differential amplifier 123 ADC 124124 _A CPU 125 zero shift unit 126 first comparator 127 second comparator 128 absolute value amplifier 129 V / F 130 Gate unit 131 Positive / negative determination unit 132 Counter 142 First counter 143 Second counter

Claims (2)

[Claims] 1. A fastening device for rotating a screwing member to fasten it to an object to be fastened, wherein the screwing member is selected from the magnitude of a rotational angular velocity in a space generated according to the rotation of the screwing member to be rotated. The fastening device is provided with a rotation angle detecting means for detecting a rotation angle of the. 2. A fastening device, wherein the rotation angle detecting means according to claim 1 is constituted by a gyro.