JPH08136244A - Detecting device for bend of bolt shank part - Google Patents

Abstract

PURPOSE: To provide an automatic sorting device which automatically detects the bend of a bolt shank part generated on the way of bolt manufacturing, after manufacturing and before packaging. CONSTITUTION: From a parts feeder used when a thread is rolled, a screw is supplied between a rolling die 2a fixed through a supply chute and a moving belt 3. By gripping the thread part with the fixed die and the moving belt 3 and then making a bolt 11 rotate, the bend generated at the bolt shank part appears at a shank part near its head (under the neck part) as magnified deflection, so that, the bend of the bolt shank part is detected by detecting the deflection at least with one sensor of touch sensors 10a and 10b having contactors 21 and 22, respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ordinary bolt having a threaded shaft portion, and in particular, a special bolt having a long shaft portion may be bent during manufacturing. The present invention relates to a bolt shaft bending detection device for automatically selecting a defective bolt having a bending after manufacturing and before packaging.

[0002]

2. Description of the Related Art As an example, a case of manufacturing M5 × 80 bolts will be described. There is no particular problem in forging and rolling, but in the case of automatic heat treatment, it is often done in the unit of tens of thousands. In this case, since it is mass produced, it is not possible to align the bolts one by one, and the bolts may overlap in a cross shape. When it is hardened at 870 ° C, it becomes soft and a large amount of cloth is piled up in a cross shape, so that the bolt shaft portion may be bent. Of course, not only the heat treatment but also the forging / rolling may cause the shaft portion to bend due to manufacturing defects. In the current state of the industry, if there is even one defective product, all the bolts manufactured in that lot are returned, and each bolt is sorted by hand. A conventional method for inspecting the bending of the shaft of a bolt is as shown in FIGS. 5 and 6. Place the bolts one by one on the V block so that they are supported at two points near the head and the tip of the bolt, and bring the tip of the dial gauge contact into the maximum deflection of the shaft, and then touch the bolt by hand. Rotate with. The difference between the maximum value and the minimum value of the measured values at that time is used as the bending of the shaft portion, and a person determines whether the value is within the allowable limit. With this method, it is not possible to make an accurate measurement unless you find out exactly where the position of the apex of the maximum bending portion is, and touch the dial gauge there.
It is difficult to do that.

[0003]

Generally, the conventional method for inspecting the bending of the shaft of a bolt has the following problems. (1) Since the work is performed manually, if the workability is poor and the number of measured objects is tens of thousands, it takes a huge amount of time and people to perform 100% inspection. (2) Since it is done manually, a measurement error occurs by an individual. (3) In the conventional measuring method, since the dial gauge is applied to the maximum deflection of the shaft portion as a guide and the bolt is rotated by hand, it is impossible to know the accurate maximum value of bending.

The main object of the present invention is to automatically inspect mass-produced bolts and to greatly reduce the time and labor required for sorting.

[0005]

In order to achieve the above object, the following means is adopted in the bending defect detecting device for the shaft portion of the bolt of the present invention. In order to detect the bending of the shaft of the bolt, use a rolling die for thread rolling on one side and a belt that moves to the other side, and push the belt toward the rolling die through an iron plate. To In the meantime, if the bolt is caught and the belt is moved in one direction, the bolt rotates.

Generally, the threaded portion of a bolt is processed by rolling, and this portion has almost no bending. Therefore, by using this portion as a reference for bending, highly accurate rotation can be realized. As a result, the bolt is in a state where only the screw part is grasped, and if the belt is moved as it is, the deformation of only the part above the bolt part appears as a runout with the thread part as a reference, and the extent of runout is the most from the thread part. The maximum is near the head of the distant bolt.

At least one touch sensor for detecting whether or not the contactor has come into contact with the shaft portion (lower portion of the neck) close to the head is installed so as to come into contact with the bolt shaft portion when the shake exceeds an allowable limit. However, the contact of the touch sensor is installed in parallel with the traveling direction of the bolt for a length equal to or longer than the moving length when the bolt makes one rotation. If the length of the contactor is shorter than that, even if the maximum shake occurs at a position where there is no contactor, it cannot be detected and the initial performance cannot be exhibited. Even if only one touch sensor is functionally sufficient, it is preferable to use two touch sensors as shown in the figure because double checking is possible.

[0008]

When the bolts are automatically inserted into the device constructed as described above from the parts feeder used for ordinary thread rolling through the supply chute, the bolts pass through the detection unit according to the movement of the belt and are installed on the way. Bending is detected by the presence or absence of contact between the contact of the touch sensor and the bolt, and the bending is ejected from the detection portion. Corresponding to the contact, the control circuit automatically distinguishes between a good product and a defective product.

[0009]

Embodiments of the present invention will be described with reference to the accompanying drawings. 1, FIG. 2, FIG. 3, and FIG. 4, a thread rolling die 2a is fixed to the inner surface of a holder 2b provided in the detection device body 1, and the thread rolling die 2a faces the rolling die 2a in the longitudinal direction in the body 1. A belt 3 that moves in one direction and a push-out plate 4 that pushes the belt 3 toward the rolling die 2a are placed on. The pushing plate 4 is supported by the shaft 8 and is pushed out by the extension force of the spring 5. However, the washer 7 and the nuts 9a and 9b make it possible for the bolt 11 to be properly caught between the rolling die 2a and the belt 3. Try to stay in position.
The position is adjusted by the nuts 9a and 9b.

Next, in FIG. 4, the bolts 11 are automatically supplied from the parts feeders normally used for thread rolling through the supply chutes 12a, 12b. The belt 3 is supported by the guide rollers 13a and 13b and the drive roller 20, and the drive roller 20 is moved in the direction indicated by the arrow by the rotation of the motor 18 via the drive belt 19.

As shown in FIG. 2, the bolt 11 is caught between the die 2a and the belt 3, and the bolt is rotated in the direction of the arrow in accordance with the moving direction of the belt 3 indicated by the arrow ▲ A ▼. Move in the direction. At this time, the shaft portion and the head portion of the bolt 11 move as shown by the broken line in FIG. 1 when the shaft portion is bent, but touch sensors 10a, 10
b is installed, and the position of the contact is adjusted so as to make contact when the allowable dimension of bending of the bolt 11 is exceeded. Further, the lengths of the contacts 21 and 22 are set to be equal to or longer than the circumference of the shaft portion of the bolt 11, that is, the length to be moved when the bolt 11 makes one rotation. The reason is that, if the lengths of the contacts 21 and 22 are shorter than the above-mentioned lengths, the touch sensors 10a and 10b do not sense the situation when the most bent portion comes to a place without the contacts. This is because defective products are mixed into non-defective products and the original purpose cannot be achieved. It is preferable that only one touch sensor 10a is functionally sufficient, but it is preferable to add two touch sensors 10b to double check.

In this way, the bolt 11 moves and finally comes off between the die 2a and the belt 3,
The shutter 15 passes through between the discharge chutes 14a and 14b of FIG.
If the product is defective, it is discharged to the defective product discharge chute 17.

[0013]

EFFECTS OF THE INVENTION A screw is fed from a parts feeder used when rolling a screw between a rolling die fixed to a moving die and a moving belt. By grasping the screw part with the fixed die and the moving belt and rotating the bolt, the bending generated in the shaft part of the bolt appears as expanded runout at the shaft part (lower neck) near the head, so this runout Bending of the bolt shaft portion is detected by detecting with a touch sensor having at least one contactor. Pass between the dies and the belt and between the discharge chutes. Usually, most of the good products flow to the good product discharge chute. After the touch sensor detects that there is a defective product, close the shutter,
It is discharged to the defective product discharge chute. Since the speed is slow, defective products are reliably discharged to the defective product discharge chute. In this way, a large number of bolts with particularly long shafts can be automatically inspected and selected with high accuracy, and labor and time can be dramatically reduced compared to the conventional manual selection by humans. Produce the effect of.

[0014]

[Brief description of drawings]

FIG. 1 shows an elevation view of the detection part of the device of the present invention.

FIG. 2 is a plan view of a detection portion of the device of the present invention, in which a bolt is inserted between the rolling die and the belt, and the belt is indicated by an arrow ▲ A.
Move in the direction indicated by ▼, and the bolt will move accordingly
The state is shown in which the touch sensor is approached while moving in the same direction while rotating in the direction indicated by A. The part indicated by the broken line shows the behavior due to bending during movement of the bolt.

FIG. 3 shows an overall elevation view of the device of the invention.

FIG. 4 is an overall plan view of the device of the present invention, in which the bolt is caught between the rolling die and the belt, the belt moves in the direction indicated by the arrow, and the bolt rotates in the direction indicated by the arrow accordingly. While moving in the same direction, the touch sensor is approached.

FIG. 5 is a front view of a conventional bending detection portion of a bolt, in which a V block supports two parts, a shaft part near the head of the bolt and a tip part, and a dial gauge for measuring the bending from above is attached to the shaft part of the bolt. The state of being in contact is shown. The part shown by the broken line shows the behavior due to bending when the bolt is rotated and the behavior of the contact tip of the dial gauge.

6 shows a side view of FIG.

FIG. 7 shows a block diagram of a control circuit of the device of the present invention. It is a figure of two touch sensors. In the case of one touch sensor, the input signal contact conversion circuit may be removed.

[Explanation of symbols]

 1 Detection Device Main Body 2a Rolling Die 2b Holder 3 Belt 4 Extrusion Plate 5 Spring 6 Fixing Plate 7 Washer 8 Shaft 9a, 9b Nut 10a, 10b Touch Sensor 11 Bolt 12a, 12b Supply Chute 13a, 13b Guide Roller 14a, 14b Discharge Chute 15 Shutter 16 Good Discharge Chute 17 Defective Discharge Chute 18 Motor 19 Drive Belt 20 Drive Roller 21 Contact 22 Contact

Claims (1)

[Claims] 1. A fixed screw rolling die for guiding a screw portion of a bolt, a belt for pressing the screw portion to rotate the die, a pressing force adjusting device for pressing the belt against the screw, and a screw. At least one touch sensor provided with a contactor for detecting a shake generated on the upper portion of the bolt shaft by rotating the guide portion, and a switching mechanism for switching a discharge passage between the defective product and a defective product by detecting a defective product Bolt shaft bend detection device.