JP2000176852A - Nut runner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve durability of parts such as a socket, a shaft, a bearing, or gear parts and improve fastening force by providing a plurality of distance sensors arranged in the socket so as to irradiate the end face of a nut, a bolt or the like. SOLUTION: When a nut 4 is housed inside a socket 2, two distance sensors 3a, 3b respectively irradiate the end face of the nut 4, to measure distances A, B from the inner face of the socket to the nut end face. The positional relation between these distance sensors 3a, 3b and the nut 4 housed in the socket 2 is set so that the distances A, B are the same value when the nut 4 is normally housed. Consequently, when the nut 4 is not normally housed, the distances A, B measured by the two sensors 3a, 3b are output as different values, and hence abnormal housing of the nut 4 can be recognized. Hereby, the life of parts such as a socket, a bearing, or gear parts can be prevented from degrading, and fastening force fastening nuts or bolts can be prevented from dispersing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a nut runner for fastening nuts, bolts and the like.

[0002]

2. Description of the Related Art A conventional nut runner will be described with reference to FIG. FIG. 4 is a side view of a conventional nut runner when tightening a nut.

In FIG. 4, a conventional nut runner 11 includes a handle 12 provided for gripping and fixing the main body of the nut runner 11 and a motor (not shown) for rotating a socket 14 described later. A built-in drive unit 15, a gear unit 16 having a built-in gear (not shown) for reducing the rotation speed of the motor, converting the rotation axis by 90 °, and transmitting a driving force to the socket 14, a nut 17 and a bolt And a socket portion 18 having a socket 14 for tightening a nut 17 and a bolt while rotating.

When the nut 17 is tightened by the nut runner 11, first, a torque value for tightening the nut 17 is set. Then, the nut 17 is inserted into the socket 14. When the switch 19 attached to the handle 12 is turned on, the motor operates, and the driving force of the motor is transmitted to the socket 14 via a gear.
Then, the nut 17 is tightened while applying torque.

[0005] Also, as shown in the figure, due to the influence of the wall 20 and the like,
When the nut runner 11 cannot be arranged vertically with respect to the nut 17, that is, when the nut 17 is
There is a case where the nut 17 cannot be normally stored in the socket 14, but even at that time, the nut 17 can be tightened if a part of the nut 17 is stored in the socket 14.

[0006]

As described above, the conventional nut runner can tighten the nut to some extent even if the nut is not sufficiently stored in the socket. However, since an uneven force is applied to the socket, the life of components such as the socket, the shaft, the bearing, and the gear portion is shortened, and the fastening force is reduced.

[0007]

Therefore, according to the present invention, according to the first aspect of the present invention, a plurality of distance sensors provided so as to irradiate an end face of a nut, a bolt or the like are provided inside the socket. A nutrunner characterized by comprising:

According to a second aspect of the present invention, there is provided a nut runner characterized in that a plurality of strain gauges are provided on a socket portion.

According to the third aspect of the present invention, the signals output from the distance sensor and the strain gauge are processed to warn the user that the nuts, bolts and the like are unreliably stored in the socket. Means are provided, and a nut runner according to claim 1 or claim 2 is provided.

[0010]

[Action] A plurality of distance sensors are attached to the inner surface of the socket, and the distance sensors measure the distances from the inner surface of the socket to the end surfaces of the nuts and bolts, and compare the respective measurement results. Detects whether bolts etc. are properly stored.

Alternatively, a plurality of strain gauges are attached to the socket. When tightening nuts, bolts, etc., the strain of the socket is measured with a strain gauge, and these measurement results are compared.
Detects whether bolts etc. are properly stored.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is an enlarged side sectional view of a socket portion of a nut runner according to a first embodiment of the present invention. FIG. 2 is an enlarged side sectional view of a socket portion of a nut runner according to a second embodiment of the present invention. FIG. 3 is an enlarged side sectional view of a socket portion of a nut runner according to a third embodiment of the present invention.

In FIG. 1, two distance sensors 3a and 3b are built in the inside of a socket 2 of a nut runner 1 and a bottom surface of the inside. Distance sensor 3
For example, a light irradiation type such as an LED or an ultrasonic type is used for a and 3b, and a distance can be obtained by measuring a time required for reflected light and sound waves to be reflected.

When the nut 4 is accommodated in the socket 2, the two distance sensors 3a and 3b irradiate the ends of the nut 4, respectively, to determine the distances A and B from the inner surface of the socket to the nut end surface. Measure.

Further, these distance sensors 3a, 3b,
The positional relationship between the nuts 4 stored in the socket 2 is such that the distances A and B have the same value if the nuts 4 are normally stored. Therefore, if the nut 4 is not properly stored, the distances A and B measured by the two sensors 3a and 3b are output as different values, and the abnormal storage of the nut 4 is recognized. it can.

In FIG. 2, two distance sensors 5a,
5b is built in the peripheral surface inside the socket 6. When the nut 4 is stored in the socket 6, the two distance sensors 5a and 5b irradiate the end faces of the male screw 7 respectively, and the distances C,
Measure D.

Then, similarly to the first embodiment, the distance sensors 5a and 5b and the nut 4 housed in the socket 6 are provided.
Is set so that the distances A and B have the same value if the nut 4 is normally stored. If the nut 4 is not properly stored, the two sensors 5
The distances C and D measured at a and 5b are output as different values, and abnormal storage of the nut 4 can be recognized.

In FIG. 3, two strain gauges 8a and 8b are attached to the tip of the outer periphery of the socket 9. The strain gauges 8a and 8b can measure the strain of the socket 9 when tightening the nut 4.

When the nut 4 is tightened, torque is gradually generated, and the socket 9 starts to be distorted.
When distortion occurs in the socket 9, the strain gauges 8a and 8b attached to the socket 9 are elongated, and the internal resistance of the strain gauges 8a and 8b changes. That is, the torque generated when the nut 4 is tightened due to the change in the internal resistance value can be measured as the amount of distortion.

If the nut is not properly stored in the socket 9, the torque applied to the socket becomes uneven, and the respective strain amounts measured by the strain gauges 8a and 8b become different values. Abnormal storage can be recognized.

As described above, the nut runner of the present invention transfers signals output from various sensors disposed therein to a control device built in the nut runner main body or to a separate control device, and the control device controls the nut in the socket. Or the tightened state can be recognized. And
If abnormal storage or abnormal tightening is performed, a means is provided to warn the user of the nut runner by uttering a buzzer or the like, or a means is provided for stopping the power supply to the nut runner. You may.

In this embodiment, the state of the nut and the like in the socket is measured using two distance sensors or two strain gauges. The number of distance sensors or strain gauges may be increased, or the arrangement position may be changed.

[0023]

According to the present invention, the life of components such as sockets, bearings and gears can be prevented from being shortened.
Variations in fastening force for fastening nuts and bolts can be prevented.

[0024]

[Brief description of the drawings]

FIG. 1 is an enlarged side sectional view of a socket portion of a nut runner according to a first embodiment of the present invention.

FIG. 2 is an enlarged side sectional view of a socket portion of a nut runner according to a second embodiment of the present invention.

FIG. 3 is an enlarged side sectional view of a socket portion of a nut runner according to a third embodiment of the present invention.

FIG. 4 is a side view of a conventional nut runner when tightening a nut.

[Explanation of symbols]

 1, 11 ... nut runner 2, 6, 9, 14 ... socket 3a, 3b, 5a, 5b ... distance sensor 4, 17 ... nut 7 ... male screw 8a, 8b ... strain gauge 12 ... handle part 15 ... drive part 16 ... Gear part 18 ... Socket part 19 ... Switch 20 ... Wall

Claims (3)

[Claims] 1. A nut runner for fastening nuts, bolts, etc., wherein a plurality of distance sensors are provided inside a socket for accommodating the nuts, bolts, etc., so as to irradiate end faces of the nuts, bolts, etc. A nut runner characterized by being performed. 2. A nut runner for fastening nuts, bolts, etc., wherein a plurality of strain gauges are provided in a socket portion. 3. A warning means for processing a signal output from the distance sensor and the strain gauge to warn a user that a nut, a bolt or the like is unreliably stored in the socket. Claim 1 and Claim 2
Nut runner as described.