JPH0575961B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a device that continuously inspects manufactured bolts for abnormalities such as thread collapse and deformation.

(Prior Art) Conventionally, in this type of inspection device, bolts to be inspected are held at required intervals along the circumference of a turntable in a state facing the generatrix direction, and the turntable is rotated intermittently at a constant angle. The bolts to be inspected are sequentially conveyed to the inspection position by rotating the bolts, and at the inspection position, an inspection wheel is formed on the outer circumferential surface of the bolt to be inspected, the same screw thread having the same lead angle as the thread of the bolt to be inspected is formed. is rotated while being in elastic pressure contact with the bolt to be inspected, with the screw on its outer surface engaged with the thread of the bolt to be inspected, and the displacement of the inspection wheel is detected to determine the thread of the bolt to be inspected. There are known devices configured to detect abnormalities.

However, conventional inspection equipment rotates the turntable intermittently and performs inspection at the inspection position when stopped, which has the disadvantage of low inspection efficiency.Moreover, bolts are used in all technical fields for mass production and mass production. As it is commonly used, its drawbacks are extremely serious.

(Problems to be Solved by the First Invention and Means for Solving the Problems) The first invention of the present application aims to improve the efficiency of bolt thread inspection, and as a means to solve the problem, it is possible to improve the efficiency of bolt thread inspection. In a configuration in which bolts to be inspected are rotatably held in a state facing the generatrix direction, and the bolts are sequentially conveyed to predetermined inspection zones by continuous rotation of the turntable, the bolts to be inspected are Inside the inspection bolt, a bolt position reference body is provided that guides the threaded portion of the bolt from the inside on a constant arc-shaped conveyance trajectory, and on the outside of the bolt to be inspected in the inspection zone, a bolt position reference body is provided that guides the threaded portion of the bolt from the inside on a constant arc-shaped conveyance trajectory. The test object has a concave thread surface formed by forming a large number of threads identical to those of the bolt to be inspected on an arcuate concave curved surface with the same curvature as the bolt to be inspected, with the same lead angle. We propose a bolt thread inspection device in which the bolt position reference body is elastically pressed sideways in a tangled state.

(Problems to be solved by the second invention and means for solving the problem) On the other hand, when using the thread inspection device of the first invention, depending on the type, size, etc. of the bolt to be inspected, the bolt that is transported to the inspection area may be The threaded part of the test object may not engage properly with the concave curved surface of the test object.
If this is left unchecked, uninspected bolts will be sent out.

The object of the second invention of the present application is to automatically correct the bolt to correct engagement when the bolt to be inspected does not engage with the concave threaded surface of the object to be inspected, and as a means for solving the problem, the bolt according to the first invention is The position reference body is a bolt position reference ring that guides the threaded portion of the bolt to be inspected from the inside so that it can roll and come in contact with the bolt on a circumferential surface, and the bolt position reference ring is rotatably supported and the threaded part of the bolt to be inspected is rotatably supported. We propose a bolt thread inspection device which doubles as a bolt engagement correction ring, which is rotated at such a rotational speed that the threaded portion of the bolt is rolled and engaged with the concavely curved thread surface of the inspection body. Embodiments of the present invention will be described below with reference to the drawings.

(Example) For convenience, an example of the second invention will be described first.

In FIGS. 1 and 2, a shaft 3 is rotatably supported via ball bearings 2, 2 in a hollow cylindrical support tube 1 with both ends open, which is vertically fixed on a base plate F. A disc-shaped turntable 4 is fitted into the upper end of the support cylinder 1 and is fixed with a fastening bolt 5. Above turntable 4
This turntable has bolt retaining grooves 6 (eight in the figure) recessed at equal intervals on its outer circumferential surface, each having a U-shaped cross section and opening outward in the direction of the generatrix. At the inspection bolt supply position around 4,
A supply chute 7 is installed that slopes downward toward the outer peripheral surface of the turntable 4 and guides the bolts B to be inspected in a freely sliding manner with the bolt heads facing upward. When the bolt holding groove 6 of the turntable is located at the feeding port, the bolt B is automatically thrown into the holding groove 6. As shown in the second figure, the bolt B is conveyed while being held with its head placed on the turntable 4 and its threaded portion protruding below the turntable 4.

In the inspection zone P, which is approximately 90 degrees apart in the rotational direction of the turntable 4, there is a A height adjustment nut 9 is screwed into the male screw portion 8 so as to be able to rise and fall freely, a ball bearing 10 is fitted to the nut 9, and the outer race of the bearing is connected to the bolt position reference and bolt engagement correction ring 11 (in this example). (hereinafter abbreviated as standard correction ring)
Under the turntable 4, the outer circumferential surface of the ring 11 contacts the threaded portion of the bolt B to be inspected from the inside, thereby guiding the outer circumferential surface of the ring 11 while holding the bolt to be inspected in a fixed position. In addition to having an arcuate conveyance track, the bolt has a rolling contact surface that actively rotates the bolt at a required rotational speed in order to correct the engagement of the bolt to be inspected with an inspection die, which will be described later.

Around the turntable 4, a guide rail 12 is disposed in close proximity to the outer peripheral surface of the turntable over a range of about a little more than half a circumference in the rotational direction from the position of the bolt supply chute 7. This prevents B from falling off.

An inspection die 13 is provided outside the bolt B to be inspected in the inspection zone P, as shown in Figure 13, and the inspection die 13 is attached to the outer periphery of the reference correction ring 11 (as shown in Figures 4 and 4a). A segment block having an arcuate concave curved surface with the same curvature as the arcuate conveyor track.A large number of screw threads 14, which are the same as those of the bolt B to be inspected, are engraved in an expanded state with the same lead angle on the concave curved surface. A curved threaded surface 15 is formed. In this example, the concave threaded surface 15 is a developed threaded surface corresponding to three rotations of the threaded portion of the bolt B to be inspected. The inspection die 13 as described above has its concave threaded surface 1
5 to face the reference correction ring 11 concentrically,
It is resiliently supported at a position where it can be engaged from the outside with the threaded portion of the bolt B to be inspected that is being transported.

The resilient support means for the inspection die 13 includes a first
3. As shown in Figure 3, a support frame 18 is fixed to a movable platen 17 that can be adjusted by moving up and down and back and forth by a normal position adjustment device 16 installed on the base plate F at the rear of the inspection zone P. frame 18
Guide sleeve 1 fixed parallel to both left and right sides of
The slide rods 20 and 20 are supported by the slide rods 9 and 19 so as to be able to slide back and forth toward the center of the turntable 4,
The rear ends of both slide rods 20, 20 are connected by a connecting bar 21, and an inspection die holder 22 is fixed to the front end, and an inspection die 13 is removably fixed to the front end of the boulder 22 with a bolt. Dice holder 22 and support frame 1
In this structure, the holder 22 and the inspection die 13 are pushed aside from the reference correction ring 11 by a coil spring 23 supported between the reference correction wheels 11 and 8.

The means for detecting an abnormality in the threads of the bolt B to be inspected is the inspection die holder 2 as shown in the first and third figures.
In this example, the displacement plate 24 is erected at the rear end of the upper surface of the support frame 18, and the displacement plate 24 is mounted on a bracket 25 protruding from the front end of the upper surface of the support frame 18.
An eddy current displacement sensor 26 is installed on the rear surface facing each other with a small interval, and detects an abnormality in the thread of the bolt to be inspected, and detects an abnormality in the thread of the bolt to be inspected.
When it is displaced backward against the spring 23, this displacement is detected by the sensor 26 and an abnormality detection signal is transmitted.

The rotational drive mechanism of the reference correction wheel 11 includes a first
2. As shown in the figure, the gear 28 fixed to the output shaft of the geared motor 27 installed under the bed plate F is meshed with the gear 30 fixed to the input shaft of the transmission 29 installed on the bed plate F. On the other hand, a vertically elongated friction wheel 32 and a pulley 33 connected to the friction wheel 32 are rotatably supported on a support 31 erected on the base plate F, and the friction wheel 32 is attached to the outer peripheral surface of the reference correction ring 11. The pulley 34 and the pulley 3 are brought into pressure contact and are fixed to the speed change output shaft of the transmission 29.
3 are connected by a belt 35, whereby the rotation of the gear motor 27 is appropriately changed in speed by a transmission 29, and this is transmitted to the standard correction wheel 11 via pulleys 34 and 33, and then a friction wheel 32, and the rotation of the gear motor 27 is The rotation is such that the bolt B to be inspected, which rolls into contact with the bolt B, is rolled and moved while engaging with the concavely curved threaded surface 15 of the inspection die 13. In this example, the reference correction ring 11 rotates at a rotational speed that is equal to the circumferential speed of the bolt B to be inspected on the pitch circle of the concave threaded surface of the inspection die 13. Such a reference correction ring 1
Due to the interlocking rotation of the bolt B to be inspected by the rotation of step 1, even if the threaded portion of the bolt B to be inspected transported to the inspection zone does not initially engage with the concave threaded surface of the inspection die 13, it is immediately corrected to the correct engagement. be.

The rotational drive mechanism of the turntable 4 includes a second
As shown in the figure, a pulley 36 fixed to the output shaft of the geared motor 27 and a pulley 37 fixed to the lower end of the shaft 3 are connected by a belt 38.

At a position slightly away from the inspection zone P in the direction of rotation of the turntable 4, a good product delivery chute 39 is disposed so as to be oriented substantially tangentially to the turntable 4 as shown in the first figure. A good product takeout plate 42 connected to the ram 41 of the air cylinder 40 installed on the outside extends above the turntable 4, and a guide piece 4 projects downward from the tip of the takeout plate 42 as shown in the fifth figure.
When the chute 39 is tilted substantially in the extending direction of the chute 39 and moved backward by the backward drive of the air cylinder 40, the guide piece 43 obliquely crosses the movement trajectory of the bottom holding groove 6 as shown in the first figure. It is located at a non-defective product take-out position extending to the entrance of the chute 39, and when moved forward, it moves to a release position inward from the bolt holding groove movement track as shown by the imaginary line in FIG. In this example, an air circuit for supplying and discharging air to and from the air cylinder 40 is provided as an example, and an abnormal output signal from the eddy current displacement sensor 26 is sent to the air circuit to drive the air cylinder 40 forward for a required time. It is designed to be driven backwards after a certain amount of time has elapsed.

At a position approximately 120 degrees away from the good product delivery chute 39 in the direction of rotation of the turntable, a defective product take-out plate 44 whose base is fixed to the outside of the turntable extends over the turntable 4 and extends from the tip of the take-out plate 44. Guide piece 45 protruding downward
As shown in the first figure, the bolt holding groove is extended to the outside of the turntable 4 by diagonally crossing the movement track of the bolt holding groove.

The function of this device will be explained along with its operation. When the geared motor 27 is started, the turntable 4 is rotated in the direction of the arrow in FIG.
9. Rotate the reference correction wheel 11 via the pulleys 34, 33 and the friction wheel 32. When the turntable 4 rotates and the bolt holding grooves 6 pass in front of the supply opening of the bolt supply chute 7, the bolts B to be inspected are sequentially supplied to the holding grooves 6 and transported to the next inspection zone P. be done. The bolt B to be inspected, which has reached the inspection zone P, has its threaded portion engaged with the concavely curved threaded surface 15 of the inspection die 13, and is pressed against the standard correction ring 11 which is rotated by being pushed by the inspection die. It is rotated at a speed that allows it to roll and move while engaging with the threaded surface 15. As a result, when the bolt B does not initially engage with the concavely curved threaded surface 15 of the inspection die 13 when it comes into contact with the concavely curved threaded surface 15, the bolt B is immediately corrected to the correct engagement with the concavely curved threaded surface 15 by the above-mentioned rotation, and then moves onto the concavely curved threaded surface 15. rolling. If the bolt B to be inspected has an abnormality such as crushed or deformed threads during the rolling, the inspection die 13 moves back against the spring 23, displacing the displacement plate 24 rearward, and converting this displacement into a vortex. The detection signal is detected by the current displacement sensor 26, and the air cylinder 40 is driven forward to move the guide piece 43 of the good product takeout plate 42 to the release position, thereby preventing the defective bolt from being sent to the good product delivery chute 39. , is pushed out from inside the holding groove 6 by the guide piece 45 of the defective product removal plate 44 in front of it. Bolts with no abnormality in their threads are removed from the inspection die 13 and placed on the good product extraction plate 42.
It is pushed out from the holding groove 6 by the guide piece 43 and guided to the non-defective product delivery chute 39.

Next, an embodiment of the first invention will be described. In this example, a means for correcting the engagement of the bolt with the inspection die is excluded depending on the type and size of the bolt, and as shown in FIG. The outer peripheral surface of the friction wheel 3 is an arc-shaped conveyance track, and the other structure is
In addition to excluding 2 and its accompanying structures, 1.
This is an example substantially the same as FIGS. 2, 3, 4, 4a, and 5.

As another embodiment of the first invention, the bolt position reference wheel 11a in FIG. 6 is rotatably fitted to the height adjustment nut 9a via a ball bearing, and the other structure is a friction wheel 32 and It is substantially the same as FIGS. 1, 2, 3, 4, 4a, and 5 except for the accompanying structures.

(Effects of the Invention) According to the bolt thread inspection device of the first invention of the present application, the bolt to be inspected is continuously conveyed in the inspection zone by continuous rotation of the turntable that holds the bolt to be inspected, and the bolt is engaged with the inspection object and threaded. It is possible to perform inspections and improve inspection efficiency.

According to the bolt thread inspection device of the second invention of the present application, in addition to the effects of the first invention, when the bolt to be inspected that is transported to the inspection zone does not engage with the concavely curved thread surface of the inspection object, the bolt position reference By rotating the bolt to be inspected at a predetermined speed with the rotation of the bolt engagement correction ring that also serves as a ring, the bolt can be automatically corrected to the correct engagement state with the concave threaded surface. Regardless of the type, size, etc., inspection can be performed reliably.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a partially cutaway plan view, FIG. 2 is a cross-sectional view taken along the line -- in FIG.
3 is a sectional view taken along the - line in FIG. 1, FIG. 4 is an enlarged plan view of the inspection die, FIG. 4a is an enlarged front view of the same as above, and FIG. FIG. 6 is a vertical sectional view of a portion of another thread inspection device. B... Bolt to be inspected, 4, 4a... Turntable, P... Inspection zone, 11... Bolt position reference and bolt engagement correction wheel, 11a... Bolt position reference wheel, 13... Inspection die, 15... ...Concave thread surface.

Claims (1)

[Claims] 1. Bolts to be inspected are rotatably held along the circumferential surface of a turntable in a state facing the generatrix direction, and the bolts are sequentially moved to predetermined inspection zones by continuous rotation of the turntable. In the conveying configuration, a bolt position reference body is provided inside the bolt to be inspected to be conveyed in the inspection zone, and a bolt position reference body is provided for guiding the threaded portion of the bolt from the inside on a constant arc-shaped conveyance trajectory, and On the outside of the bolt to be inspected, there is an inspection object having a concave curved thread surface formed by forming a number of threads identical to those of the bolt to be inspected at the same lead angle on an arcuate concave curved surface having the same curvature as the constant arc-shaped conveyance path. A bolt thread inspection device, wherein the bolt position reference body is elastically pressed sideways with its concave thread surface engaged with the threaded portion of the bolt to be inspected from the outside. 2. The bolt position reference body is a bolt position reference ring that is held on a circumferential surface of the threaded portion of the bolt to be inspected so that it can roll and come into contact with the threaded portion of the bolt to be inspected from the inside, and the bolt position reference ring is rotatably supported and Claim 1, wherein the bolt is rotated at a rotational speed such that the threaded portion of the bolt to be inspected engages with the concavely curved threaded surface of the inspection body and rolls and moves, and also serves as a bolt engagement correction ring. The bolt thread inspection device described in .