JP2001009748A - Angle wrench - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve visibility of a display of a twisting angle, and to enhance smoothness and facility of fastening work by electrically processing/displaying a twisting angle value after screw fastening torque reaches snag torque on the basis of detecting output from an angular velocity sensor or an angular acceleration sensor. SOLUTION: An angular velocity sensor or an angular acceleration sensor 18 is internally installed in a sensor case 16 installed on a handle tube 13, and a converting circuit for converting a signal outputted by the sensor 18 into an angle signal, a display driving circuit and a display 20 are incorporated into a processing displaying case 17. A fastening object screw is fitted to a head part 15 of a torque wrench 11 to fasten a screw by reciprocatively rotating the handle tube 134 by a grip part 12. The sensor 18 is started on the basis of snag torque detecting output from a strain gauge 24 to successively output angular velocity or angular acceleration signal, and a twisting angle after generating snag torque is electrically successively counted and displayed by the display 20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an angle wrench which can be used in a screw tightening operation employing an angle fastening method,
In particular, the present invention relates to an angle wrench provided with an electric sensor and a display for sequentially displaying the twist angle of a screw (an angle wrench) at the time of fastening a screw to be fastened.

[0002]

2. Description of the Related Art An object to be fastened such as a device is
Screw tightening with the specified tightening force using the screw to be tightened
As a fastening method, for example, torque fastening using a torque wrench
After tightening the screw with a torque wrench,
An angle fastening method that gives a twist amount by a specified angle within the plastic region,
Further, a gradient fastening method and the like are well known. This torque fastening method
And the angle fastening method will be specifically described with reference to FIG.
The torque fastening method detects and sets the fastening torque value of the screw.
Using a torque wrench that can
For example, the toggle link built into the torque wrench operates
Snag point, that is, the set torque value T₁ Screw
The angle fastening method uses a torque wrench.
Of the toggle link etc. built into the torque wrench
The torque detection mechanism operates and the set torque value T₁ (Snuggt
Torque value), then tighten the torque wrench
Predetermined twist angle θ within the plastic region₁ Just rotate and tighten the screw
Force T _Two This is the fastening method.

[0003] The gradient fastening method is a fastening method in which a deviation point between an elastic region and a plastic region of a screw is found and the screw is tightened.

[0004]

However, in the screw tightening operation employing the above angle tightening method, when the screw is tightened by the torque wrench, the rotation angle of the torque wrench after reaching the snag torque point is detected. For this purpose, mechanical positioning means such as a base member or the like which is conventionally used as an angle reference of an angle counter, such as a pulse encoder, attached to a torque wrench is required.

Therefore, in a conventional example for mechanically positioning a base member in this angle counter, as shown in FIG. 6, the stator 4 of the angle sensor 2 is fixed to the head of the torque wrench 1 and the angle sensor The rotor 3 is connected to the flexible shaft 5 and the tip of the flexible shaft 5 is connected to the base 7 via a fixed body 6 made of a magnet or the like.
Is fixed so that it cannot rotate.

In such a mechanical positioning means for the angle counter base member, the fixing body 6 must be set each time each screw is tightened, which makes the screw tightening work complicated and further increases the screw tightening. At the time of work, there was a drawback that the flexible shaft 5 and the fixed body 6 hindered the screw tightening workability, and the like.

SUMMARY OF THE INVENTION The present invention has been made in view of such a conventional disadvantage, and uses a manual screw fastener capable of electrically setting and detecting a fastening torque value and fastens a screw employing an angle fastening method. An angle wrench provided with a sensor capable of electrically detecting and displaying a wrench twist angle at the time of work, particularly a flexible shaft 5 and a fixed body shown in, for example, a conventional example. A sensor capable of detecting the twist angle after the snag torque is reached without using accessories such as 6 is provided.
By providing an electrical indicator capable of displaying the twist angle change electrically sequentially, the visibility of the twist angle display at the time of the screw fastening operation employing the angle fastening method is improved, and furthermore, the fastening is performed. A first object is to increase the smoothness and ease of work.

It is a second object of the present invention to reduce the size and cost of the sensor used in the torque wrench, and to improve the workability and economy of the screw fastener.

[0009]

In order to achieve the first and second objects, according to the first aspect of the present invention, a manual screw fastener provided with a fastening torque detecting means is provided with an angular velocity sensor or an angular acceleration. A sensor is provided, and the torsion angle value of the manual screw fastener after the screw fastening torque by the manual screw fastener reaches the snag torque is based on a detection output obtained from the angular velocity sensor or the angular acceleration sensor. It is characterized by an angle wrench provided with a twist angle display for performing electrical processing display.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on an embodiment shown in the drawings. 1 and 2 show the overall shape of a torque wrench that is a manual screw fastener.

The torque wrench 11 has a handle tube 13 having a grip portion 12 attached to a tail end thereof, and a head member 15 supported by a support shaft 14 attached to a distal end portion of the handle tube 13. A locking pin 23 for fixing the tail end of the head member 15 so as not to be displaceable is fixed to a substantially middle portion of the handle tube 13, and the head member 15 is fixed to the support shaft 1 by the locking pin 23.
The rotation about the fulcrum 4 is disabled. At a predetermined position of the head member 15, for example, a strain gauge 24 is attached.

Reference numeral 16 denotes a sensor case attached to the outside of the handle tube 13, and 17 denotes a processing display case similarly supported up and down on the outside of the handle tube 13. Inside, for example, an angular velocity sensor or an angular acceleration sensor 18 such as a gyroscope is provided. As shown in FIG. 4, a conversion circuit 1 for converting an angular velocity or angular acceleration signal output from the angular velocity sensor or angular acceleration sensor 18 into an angle signal is provided inside the processing display case 17.
9 (for example, an integration circuit), a display drive circuit 21 for electrically displaying the value of the angle signal obtained by the conversion circuit 19 on the display 20, and the display 20 are incorporated. .

As shown in FIG. 3, the processing display case 17 is supported by a support shaft 22 fixed in position parallel to the axial direction of the handle tube 13. For example, the display surface can be displaced from a horizontal direction to a vertical direction.

The operation of the present embodiment has been described above. Next, the operation of the embodiment will be described. The head member 15 of the torque wrench 11 which is a manual screw fastener is connected to a head screw 15 (not shown) via a socket (not shown) or the like. ), The grip portion 12 is gripped, and the handle tube 13 is repeatedly rotated back and forth, whereby the screw to be fastened is tightened.

When the screw tightening torque reaches a specified fastening torque (snag torque), the output from the strain gauge 24 detects that the screw to be fastened has reached the snag torque. In the angle fastening method, the torque wrench 11 is further rotated by a predetermined angle after reaching the snag torque.

Then, when the fastening torque value of the screw to be fastened reaches the snag torque, the fact that the snag torque has been reached is detected by the torque detection output from the strain gauge 24, and the angular velocity is determined based on the snag torque detection output. The sensor or the angular acceleration sensor 18 is activated, and the torque wrench 1 after the torque wrench 11 reaches the snag torque.
One angular velocity signal or angular acceleration signal is sequentially output. The angular velocity signal or the angular acceleration signal output from the sensor 18 is converted (integrated) by the conversion circuit 19, and is output from the conversion circuit 19 as an angle signal. This angle signal is used as a drive signal for the display 20 by the display drive circuit 21, and the display 20 electrically counts and displays the twist angle of the torque wrench after the occurrence of the snag torque.

Although not shown, if a warning device is provided that emits a pre-bell when the twist angle of the torque wrench approaches a set angle, and emits a main bell when the twist angle exceeds the set angle, the screw can be screwed down. The tightening operator can visually and / or audibly know the twist angle information of the torque wrench by the alarm.

As described above, according to the angle wrench of the above embodiment, since the angular velocity sensor or the angular acceleration sensor is used as the sensor for detecting the twist angle after the snag torque of the torque wrench, the torque wrench is used. The torsion angle after the snag torque can be displayed electrically and sequentially on the display, so that the screw fastening using the angle fastening method can be performed accurately and the twist angle display during the work The visibility is improved. In addition, the use of mechanical accessories such as the flexible shaft and the fixed body described in the conventional example can be omitted, thereby greatly improving the workability and ease of screw fastening.

The angle sensor or the angular acceleration sensor used for detecting the twist angle is small and the circuit configuration can be simplified, so that the torque wrench can be made relatively small. In addition to this, it is also possible to increase economic efficiency by reducing costs and the like.

Further, according to the above-described embodiment, the display surface of the display device 20 can be changed, so that the display surface can be most easily viewed by an operator in accordance with the screw tightening posture of the operator. This makes it easy to visually check the twist angle of the torque wrench displayed on the display 20, and the screw tightening operation at the set angle is performed smoothly.

[0021]

As described above, according to the angle wrench according to the present invention, during the screw fastening operation using the manual screw fastener, the torque after the snag torque has been reached by the electric processing display means. Since the rotation angle of the wrench can be displayed electrically, the screw can be tightened while confirming the twist angle of the angle wrench on this electrical display. The fastening operation can be performed accurately and easily. Further, the angle wrench can be relatively reduced in size, the handling of the angle wrench becomes easy, and furthermore, there is an effect that the cost is reduced and the economy is enhanced.

[Brief description of the drawings]

FIG. 1 is a plan view showing an embodiment of an angle wrench according to the present invention.

FIG. 2 is a side view showing an embodiment of the angle wrench according to the present invention.

FIG. 3 is an explanatory view of the operation of the display case of the embodiment of the angle wrench according to the present invention.

FIG. 4 is a circuit diagram showing an embodiment of an angle wrench according to the present invention.

FIG. 5 is a characteristic diagram showing a relationship between a screw tightening axial force and a twist angle.

FIG. 6 is an explanatory sectional view of a main part of a conventional angle wrench.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 ... Torque wrench 12 ... Grip part 13 ... Handle tube 14 ... Support shaft 15 ... Head member 16 ... Sensor case 17 ... Processing display case 18 ... Sensor 19 ... Conversion circuit 20 ... Display 21 ... Display drive circuit 22 ... Support shaft 23 ... locking pin 24 ... strain gauge

Claims (1)

[Claims] An angular velocity sensor or an angular acceleration sensor is provided in a manual screw fastener provided with a fastening torque detecting means, and a manual screw fastening after the screw fastening torque by the manual screw fastener reaches a snag torque. An angle wrench, comprising: a twist angle display for electrically processing and displaying a twist angle value of the vessel based on a detection output obtained from the angular velocity sensor or the angular acceleration sensor.