JP2023107420A - Screw hole quality guarantee device - Google Patents

Abstract

To provide a screw hole quality guarantee device with a structure that facilitates attachment and detachment of quality guaranteeing tools for inspection and re-tapping, and is adaptive to an angle of deviation of a screw hole and effective in up/down movement and centering of the quality guaranteeing tools.SOLUTION: A screw hole quality guarantee device inserts a quality guaranteeing tool 1 into a screw hole formed in an article to perform inspection, and comprises: a rotation transmission shaft 19 which is fitted to the quality guaranteeing tool 1 to rotate it; a first steel ball 14 which abuts on a peripheral edge part of the quality guaranteeing tool 1; a second steel ball 15 which is fitted to a groove part 1a provided to the quality guaranteeing tool 1 and also larger than the first steel ball 14; a retainer 13 which retains the first steel ball 14 and second steel ball 15; a steel ball presser 12 which is provided with a first taper part 12a abutting on the first steel ball 14 to increase the diameter downward and a second taper part 12b abutting on the second steel ball 15 to increase the diameter downward, and that can move up and down; and a tool connection part which comprises energizing means for energizing the steel ball presser 12 downward.SELECTED DRAWING: Figure 2

Description

The present invention relates to a threaded hole quality assurance device for inserting a quality assurance tool into a threaded hole formed in an article.

2. Description of the Related Art Conventionally, many screw holes are formed in industrial parts such as automotive parts, and screw hole inspection devices for inspecting the quality of screw diameters and screw depths of screw holes have been proposed.

For example, in Patent Document 1, the upper and lower limits of a proper screwing torque value corresponding to a proper screw diameter are set in advance, and the upper and lower limits of a proper screw depth position corresponding to a proper screw depth are set in advance. In addition, an invention relating to a screw hole inspection device in which appropriate torque-up values are set in advance and these values are compared with the detected torque values to inspect the quality of the screw diameter and screw depth. ing.

Further, in Patent Document 2, after a screw gauge is moved by a robot arm provided with a force detection unit and brought into contact with a screw hole, the force detection unit detects the force applied to the screw gauge and moves the screw gauge. The invention relates to a control device that allows a screw gauge to be easily and accurately fastened to a screw hole by allowing the screw gauge to be tightened.

Further, in Patent Document 3, a screw hole is mounted in a positional state such that the position of the start point of the complete screw thread of the screw gauge always has a constant phase difference with respect to the screwing start position of the screw hole to be inspected. An invention relating to an inspection device is described. Further, by providing an axis deviation allowance part that permits axis deviation of the rotating shaft part, even if the central axis of the screw gauge and the central axis of the screw hole are slightly misaligned, the screw gauge can be horizontally moved to this position. It is designed to absorb deviations.

JP-A-9-280854 Japanese Patent Application Laid-Open No. 2018-202602 JP 2018-77060 A

By the way, the screw holes in the screw hole inspection have various screw diameters depending on the part even within the same part. In addition, the inspection tool (screw gauge) used for each screw hole has no thread (no tap), can be properly screwed and inserted (GO), and cannot be inserted (NG). It may be a combination of multiple things. Therefore, the inspection tool used in the screw hole inspection device needs to be replaced frequently, so a connection structure that is easy to attach and detach is required.

In addition, due to manufacturing errors, the screw holes may be slightly inclined with respect to the design angle (declination) even in parts of the same type. Aside from extreme inclination, if the angle of declination is within the allowable range, it should be judged as good. madness will occur.

There is also room for improvement in the floating mechanism for centering the inspection tool.

Furthermore, the same problem arises not only in the inspection of screw holes but also in work (retapping) for removing welding dust and the like adhering to screw holes.

The present invention is intended to solve the above-mentioned conventional problems, it is easy to attach and detach quality assurance tools for inspection and re-tapping, it is possible to deal with deviation angles of screw holes, and it is possible to move the quality assurance tools up and down. To provide a screw hole quality assurance device having a structure effective also for movement and centering.

In order to solve the above problems, a screw hole quality assurance device of the present invention is a screw hole quality assurance device for inserting a quality assurance tool into a screw hole formed in an article, wherein the quality assurance tool is fitted to the screw hole quality assurance device. a rotation transmission shaft that rotates with a force, a first steel ball that abuts against the peripheral edge of the quality assurance tool, and a second steel ball that is larger than the first steel ball and fits into a groove provided in the quality assurance tool. a retainer that retains steel balls, the first steel balls and the second steel balls, a first tapered portion that abuts on the first steel balls and expands in diameter downward, and the second steel ball. A tool connecting portion comprising a vertically movable steel ball retainer provided with a second tapered portion that abuts against a steel ball and expands downward, and a biasing means that biases the steel ball retainer downward. characterized by having

Also preferably, a fixed table, a movable frame that is moved by external stress, a fixed magnet provided on the fixed table, a movable magnet provided on the movable frame, and a magnet moving cylinder that moves the movable magnet. characterized by having a floating portion with

In the above, the quality assurance includes screw hole inspection for judging the quality of the screw diameter, screw depth, etc. of the screw hole, and work (retapping) for removing welding dust and the like adhering to the screw hole.

The screw hole quality assurance device of the present invention is a screw hole quality assurance device for inserting a quality assurance tool into a screw hole formed in an article. A rotation transmission shaft fitted to and rotated by the quality assurance tool, a first steel ball in contact with the peripheral edge of the quality assurance tool, and a first steel ball fitted in a groove provided in the quality assurance tool. a second steel ball larger than the steel ball, a retainer holding the first steel ball and the second steel ball, and a first tapered portion contacting the first steel ball and expanding downward in diameter and a vertically movable steel ball retainer provided with a second tapered portion that abuts on the second steel ball and expands downward in diameter; and biasing means that biases the steel ball retainer downward. It has a tool connection.

When the steel ball retainer moves up and down, the position of contact between the first taper portion and the first steel ball changes, and the position of contact between the second taper portion and the second steel ball also changes. and the second steel ball move in a horizontal direction (inward and outward directions) perpendicular to the axis of rotation. When the second steel ball moves inward, the groove provided in the quality assurance tool and the second steel ball are fitted into a connected state (attached state). When the second steel ball moves outward, the fitting between the groove provided in the quality assurance tool and the second steel ball is released, resulting in a disconnected state (disconnected state). Since the steel ball retainer is biased downward, it remains attached after the quality assurance tool is attached.

In addition, when external stress acts horizontally on the quality assurance tool with the screw hole deviated, a force acts to push the first steel ball and the second steel ball outward from the quality assurance tool. At the same time, a force acts to push the steel ball retainer upward. As a result, the quality assurance tool can continue to rotate while absorbing the external stress to the quality assurance tool due to the deflection angle of the screw hole. The steel ball retainer is biased downward so that the quality assurance tool returns to a vertical position when the external stress is removed.

In addition, the floating section includes a fixed table, a movable frame that is moved by external stress, a fixed magnet provided on the fixed table, a movable magnet provided on the movable frame, and a magnet moving cylinder that moves the movable magnet. , the quality assurance tool can be centered without increasing the repulsive force over a wide stroke.

As described above, the screw hole quality assurance device of the present invention can easily attach and detach quality assurance tools for inspection and retapping, and can cope with deviation angles of screw holes. It also has an effective structure for centering.

BRIEF DESCRIPTION OF THE DRAWINGS It is a front view which shows the screw hole quality assurance apparatus which concerns on embodiment of this invention. It is (A) a cross-sectional view and (B) a vertical cross-sectional view showing the tool connecting portion in a state in which the quality assurance tool is attached. It is (A) a cross-sectional view and (B) a longitudinal cross-sectional view showing the tool connecting portion in a state in which the quality assurance tool is removed. It is (A) a cross-sectional view, (B) a vertical cross-sectional view (normal), and (C) a vertical cross-sectional view (deviation angle) showing the tool connection portion during operation. It is (A) a front view which shows a rotation transmission shaft, (B) is a cross-sectional view of a front-end|tip part. It is (A) a top view, (B) a vertical cross-sectional view (upward), and (C) a vertical cross-sectional view (downward) showing a hollow cylinder part. It is a top view which shows a floating part (X direction). 4 is a plan view showing a floating portion (Y direction); FIG. It is a side view which shows a floating part.

Next, a screw hole quality assurance device according to an embodiment of the present invention will be described with reference to FIGS. 1 to 9. FIG. A screw hole quality assurance device 100 according to this embodiment inserts a quality assurance tool into a screw hole formed in an industrial part (article) such as an automobile part. The quality assurance includes a screw hole inspection for judging the quality of the screw diameter, screw depth, etc., and an operation (retapping) for removing welding dust adhering to the screw hole.

FIG. 1 is a front view showing a screw hole quality assurance device 100. FIG. The screw hole quality assurance device 100 is attached to a robot arm (not shown) of an industrial robot via the robot attachment portion 5 . Industrial robots have information on screw holes formed in articles (screw diameter, screw depth, position, etc.), select screw holes to be inserted and quality assurance tools to be used, and control the robot arm. While doing so, the attachment/detachment of the quality assurance tool, insertion into the screw hole, pass/fail judgment, re-tapping, etc. are automatically performed. Good/bad judgment can be made based on a known method (standard).

A screw hole quality assurance device 100 includes a quality assurance tool 1 having a measuring gauge 2 (or a re-tapped part) attached to the tip, a tool connection part 10 for connecting the quality assurance tool 1, and the quality assurance tool 1 up and down. Hollow cylinder part 20 for moving, rotation motor 3 for rotating quality assurance tool 1, depth measurement part 4 for measuring screw depth of screw hole, and horizontal movement of screw hole quality assurance device 100 It has a floating part 30 that The tool connecting portion 10, the hollow cylinder portion 20 and the floating portion 30 will be described in detail below.

2A and 2B are a cross-sectional view and a vertical cross-sectional view, respectively, showing the tool connecting portion 10 with the quality assurance tool attached. 3A and 3B are a cross-sectional view and a vertical cross-sectional view, respectively, showing the tool connecting portion 10 in a state in which the quality assurance tool is removed.

The tool connection portion 10 includes an outer ring 11, a steel ball retainer 12, a retainer 13, first steel balls 14, second steel balls 15, a radial bearing 16, thrust bearings 17 and 18, a rotation transmission shaft 19, and biasing means. (not shown).

The outer ring 11 is vertically moved by a vertical driving cylinder attached to the device, and the outer ring 11 holds a radial bearing 16 , thrust bearings 17 and 18 , and a steel ball holder 12 . As the outer ring 11 moves up and down, the radial bearing 16, the thrust bearings 17 and 18, and the steel ball retainer 12 also move up and down.

The steel ball retainer 12 is a tubular body having a first tapered portion 12a and a second tapered portion 12b on its inner wall surface. The first taper portion 12a is located above the second taper portion 12b, expands in diameter downward, and abuts on the first steel ball 14. As shown in FIG. The second tapered portion 12b is located below the first tapered portion 12a, expands in diameter downward, and abuts on the second steel ball 15. As shown in FIG. The inner wall surface of the steel ball retainer 12 gradually widens in inner diameter in the order of an upper flat portion, a first tapered portion 12a, a middle flat portion, a second tapered portion 12b, and a lower flat portion.

The first steel ball 14 and the second steel ball 15 are held by a cylindrical retainer 13 having openings corresponding to each steel ball. The cage 13 is not held by the outer ring 11 and does not move up and down according to the vertical movement of the outer ring 11 . The second steel ball 15 is larger than the first steel ball 14 . In this embodiment, the number of the first steel balls 14 and the number of the second steel balls 15 are six, respectively, but the present invention is not limited to this. It can be less or more than this.

The first steel ball 14 is in contact with the upper peripheral edge portion of the quality assurance tool 1 in the mounted state of the quality assurance tool 1 shown in FIG. The second steel ball 15 is fitted in the groove 1a provided in the peripheral portion of the quality assurance tool 1 in the mounted state of the quality assurance tool 1 shown in FIG.

A biasing means (not shown) of the tool connecting portion 10 biases the outer ring 11 downward, and the steel ball retainer 12 held by the outer ring 11 is always biased downward.

In the mounting state of the quality assurance tool 1 shown in FIG. 2, the outer ring 11 (steel ball retainer 12) moves downward, and the second steel ball 15 is pushed inward by the second tapered portion 12b. Then, the second steel ball 15 fits into the groove portion 1a of the quality assurance tool 1, and the quality assurance tool 1 can be maintained in the attached state.

At this time, the rotation transmission shaft 19 is inserted into the fitting hole 1b provided on the top surface of the quality assurance tool 1 . As the rotation transmission shaft 19 rotates, the quality assurance tool 1 rotates.

On the other hand, in the removed state of the quality assurance tool 1 shown in FIG. Due to the decrease, the second steel ball 15 moves outside the installed state. Then, the second steel ball 15 is released from the groove portion 1a of the quality assurance tool 1, and the quality assurance tool 1 can be removed.

FIG. 4 shows (A) a cross-sectional view, (B) a vertical cross-sectional view (normal), and (C) a vertical cross-sectional view (deviation angle) showing the tool connecting portion during operation. As shown in FIGS. 4A and 4B, when the screw holes are formed as designed (usually), the quality assurance tool 1 is mounted vertically on the tool connecting portion 10. , rotates in accordance with the rotation of the rotation transmission shaft 19, and the steel ball retainer 12, the first steel ball 14, and the second steel ball 15 also rotate in the illustrated direction.

On the other hand, as shown in FIG. 4(C), when the screw hole is not formed as designed and is inclined (deviation), the quality assurance tool 1 is inserted into the screw hole. , an external stress acts in the lateral direction. As a result, a force acts on the first steel ball 14 and the second steel ball 15 in the direction of pushing them out, but the steel ball retainer 12 rises to absorb this force. When the quality assurance tool 1 returns to vertical and the external stress disappears, the steel ball retainer 12, which is always downwardly biased, moves downward to its normal position. The steel ball retainer angle (taper angle) of the steel ball retainer 12 is set so that the first steel ball 14 and the second steel ball 15 move outward when external stress is applied.

5A and 5B are a front view and a cross-sectional view of the tip portion of the rotation transmission shaft 19, respectively. The distal end portion 19a of the rotation transmission shaft 19 has a substantially spherical shape when viewed from the side, but has a hexagonal cross section. By making the cross section hexagonal, the rotational force is reliably transmitted to the quality assurance tool 1, and by making the side view approximately spherical, the rotational force is transmitted even when the quality assurance tool 1 is tilted. to maintain rotation. The fitting hole 1b of the quality assurance tool 1 is also hexagonal.

FIG. 6 shows (A) a plan view, (B) a vertical cross-sectional view (upward), and (C) a vertical cross-sectional view (downward) showing the hollow cylinder portion 20 . The hollow cylinder portion 20 includes a cylinder tube 21, a piston 22 and a spring 23. The cylinder tube 21 is a tubular body having a hollow portion 6 penetrating in the center axial direction. The piston 22 is a cylindrical body that moves up and down within the wall surface of the cylindrical cylinder tube 21 . The cylinder tube 21 and the piston 22 are connected by a spring 23 that urges the piston 22 upward. The piston 22 moves downward due to pressure such as air, and returns upward when the pressure is released. . By combining the cylindrical cylinder tube 21 and the cylindrical piston 22 in this manner, the hollow portion 6 is obtained, and the hollow portion 6 is effectively used as a passage for the rotation shaft of the screw hole quality assurance device 100. can do. Note that the biasing means is not limited to springs.

The floating portion 30 will be described with reference to FIGS. 7 to 9. FIG. The floating portion 30 is composed of an X-direction floating portion 40 and a Y-direction floating portion 50 . 7 is a plan view showing the floating portion 40 (X direction), FIG. 8 is a plan view showing the floating portion 50 (Y direction), and FIG. 9 is a side view showing the floating portion 30. As shown in FIG. Note that the horizontal direction in FIGS. 7 and 8 is the X direction, and the vertical direction is the Y direction.

The floating unit 40 includes a fixed table 41, a movable frame 42 movable in accordance with the movement of the quality assurance tool 1 in the X direction, fixed magnets 47, 47, 47, 48, 48, 48 provided on the fixed table 41, Movable magnets 45, 45, 45, 46, 46, 46 provided on the movable frame 42, magnet moving cylinders 43a, 43b for moving the movable magnets 45, 45, 45, magnets for moving the movable magnets 46, 46, 46 It has moving cylinders 44a and 44b. The three movable magnets 45 are held by the magnet holder 43c, and the magnet moving cylinders 43a and 43b are connected to the magnet holder 43c. Similarly, three movable magnets 46 are held by a magnet holder 44c, and magnet moving cylinders 44a and 44b are connected to the magnet holder 44c.

The movable magnet 45 and the fixed magnet 47 repel each other. Similarly, the movable magnet 46 and the fixed magnet 48 repel. By extending and contracting the magnet moving cylinders 43a and 43b and the magnet moving cylinders 44a and 44b, the repulsive force between the movable magnet and the fixed magnet can be adjusted. For example, in the state of FIG. 7, the repulsive force between the movable magnet 46 and the fixed magnet 48 is greater than the repulsive force between the movable magnet 45 and the fixed magnet 47 . By changing the positions of the movable magnets 45 and 46 when the movable frame 42 is moved, it is possible to control the left and right repulsive forces to approach each other.

The floating portion 50 is obtained by rotating the floating portion 40 by 90 degrees so as to correspond to the movement in the Y direction. Since the configuration of each part is the same as that of the floating part 40, description thereof will be omitted. As shown in FIG. 9, the floating section 30 is constructed by laminating an X-direction floating section 40 and a Y-direction floating section 50, and is adapted to move on the XY plane.

When an external stress is generated due to the deviation angle of the screw hole, the floating part 30 can also cope with it in addition to the above-described tool connection part 10 . In the case of a general floating mechanism, the repulsive force (or attractive force) increases according to the amount of displacement, so the amount of floating slide is very small and the range of use is limited. On the other hand, the floating part 30 according to the present embodiment changes the positions of the movable magnets 45, 46, 55, 56 when the movable frames 42, 52 move, so that the front, rear, left, and right repulsive forces approach each other. The stroke amount can be increased by controlling and stabilizing the stroke.

In FIG. 7, springs 49 are attached between the magnet moving cylinders 43a, 43b and the magnet holding portion 43c, and between the magnet moving cylinders 44a, 44b and the magnet holding portion 44c. The spring 49 is for use when the screw hole quality assurance device 100 is tilted horizontally (when a quality assurance tool is inserted horizontally). Gravity acts on the floating portion 40 when the screw hole quality assurance device 100 is tilted horizontally. The spring 49 urges in a direction to cancel the influence of gravity at this time. The same applies to the floating portion 50 shown in FIG.

A screw hole quality assurance device 100 according to this embodiment is a screw hole quality assurance device for inserting a quality assurance tool 1 into a screw hole formed in an article. A rotation transmission shaft 19 fitted to and rotated by the quality assurance tool 1 , a first steel ball 14 abutting on the peripheral edge of the quality assurance tool 1 , and a groove 1 a provided in the quality assurance tool 1 . a second steel ball 15 that is larger than the first steel ball 14 fitted to the cage, a retainer 13 that holds the first steel ball 14 and the second steel ball 15, and the first steel ball 14 a vertically movable steel ball retainer 12 provided with a first tapered portion 12a expanding downward in diameter and a second tapered portion 12b contacting with a second steel ball 15 and expanding in diameter downward; It has a tool connecting portion 10 with biasing means for biasing the steel ball retainer 12 downward.

When the steel ball retainer 12 moves up and down, the contact position between the first taper portion 12a and the first steel ball 14 changes, and the contact position between the second taper portion 12b and the second steel ball 15 changes. The first steel ball 14 and the second steel ball 15 move in the horizontal direction (inward and outward directions) orthogonal to the rotation axis. When the second steel ball 15 moves inward, the groove 1a provided in the quality assurance tool 1 and the second steel ball 15 are fitted into a connected state (attached state). When the second steel ball 15 moves outward, the fitting between the groove 1a provided in the quality assurance tool 1 and the second steel ball 15 is released, resulting in a disconnected state (disconnected state). Since the steel ball retainer 12 is biased downward, the attached state is maintained after the quality assurance tool 1 is attached.

Further, when an external stress acts horizontally on the quality assurance tool 1 with the screw hole deviated, a force pushing out the first steel ball 14 and the second steel ball 15 from the quality assurance tool 1 is generated. In accordance with this, a force that pushes the steel ball retainer 12 upward acts. As a result, the quality assurance tool 1 can continue to rotate while absorbing the external stress applied to the quality assurance tool 1 due to the deflection angle of the screw hole. Since the steel ball retainer 12 is biased downward, the quality assurance tool 1 returns to its vertical position when the external stress is removed.

A fixed table 31, a movable frame 32 which is moved by external stress, a fixed magnet 33 provided on the fixed table 31, a movable magnet 34 provided on the movable frame 32, and a magnet moving magnet for moving the movable magnet 34. Since the floating part 30 has the cylinder 35, the quality assurance tool 1 can be centered without increasing the repulsive force even with a wide stroke amount.

As described above, the screw hole quality assurance device 100 according to the present embodiment can easily attach and detach the quality assurance tool 1 for inspection and retapping, and can cope with deviation angles of screw holes. It has an effective structure for vertical movement and centering of the tool 1 as well.

Although the screw hole quality assurance device according to the embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and various other modifications are possible.

For example, in the above-described embodiment, the screw hole quality assurance device 100 is attached to the robot arm of the industrial robot, but the attachment location is not particularly limited, such as transport equipment, fixed equipment, and walls.

In the above-described embodiment, the floating portion 30 is divided into the X-direction floating portion 40 and the Y-direction floating portion 50, but the X-direction and the Y-direction may be integrally formed. Alternatively, a ring-shaped movable frame may be provided around a circular fixed table so that the magnets face each other.

REFERENCE SIGNS LIST 1 quality assurance tool 2 measurement gauge 3 rotation motor 4 depth measurement section 5 robot mounting section 6 hollow section 10 tool connection section 11 outer ring 12 steel ball retainer 13 retainer 14 first steel ball 15 second steel ball 16 Radial bearing 17 Thrust bearing 18 Thrust bearing 19 Rotation transmission shaft 20 Hollow cylinder part 21 Cylinder tube 22 Piston 23 Spring 30 Floating part 40 Floating part (X direction)
41 Fixed table 42 Movable frame 43a Magnet moving cylinder 43b Magnet moving cylinder 43c Magnet holding part 44a Magnet moving cylinder 44a Magnet moving cylinder 44b Magnet moving cylinder 44c Magnet holding part 45 Movable magnet 46 Movable magnet 47 Fixed magnet 48 Fixed Magnet 49 Spring 50 Floating part (Y direction)
51 Fixed table 52 Movable frame 53a Magnet moving cylinder 53b Magnet moving cylinder 53c Magnet holding part 54a Magnet moving cylinder 54a Magnet moving cylinder 54b Magnet moving cylinder 54c Magnet holding part 55 Movable magnet 56 Movable magnet 57 Fixed magnet 58 Fixed Magnet 59 Spring 100 Screw hole quality assurance device

Claims (2)

A screw hole quality assurance device for inserting a quality assurance tool into a screw hole formed in an article,
A rotation transmission shaft that fits and rotates the quality assurance tool, a first steel ball that contacts the peripheral edge of the quality assurance tool, and a first steel ball that fits into a groove provided in the quality assurance tool. a second steel ball that is larger than the first steel ball; a retainer that holds the first steel ball and the second steel ball; a vertically movable steel ball retainer provided with a first tapered portion and a second tapered portion that abuts on the second steel ball and expands in diameter downward; A threaded hole quality assurance device, comprising: a tool connection with force means. A floating device comprising a fixed table, a movable frame movable by external stress, a fixed magnet provided on the fixed table, a movable magnet provided on the movable frame, and a magnet moving cylinder for moving the movable magnet 2. The screw hole quality assurance device according to claim 1, further comprising a part.

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