JPH08187626A - Nut holding device - Google Patents

Abstract

PURPOSE: To securely hold a nut with a small-size and a light-weight without damage thereon. CONSTITUTION: A guide pin 25 capable of being inserted in and pulled out from a threaded hole 10b of a nut 10 is fixed to a support shaft 23 of a table 20. A nut holder 27 being fitted around the nut 10 and having the same center as the guide pin 25 is mounted turnably by a bracket 26 fixed to the table 20. A plunger 30 applying a resistance-to-turning to a lower face of the holder 27 is arranged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nut holding device for properly holding a nut and delivering the nut to a socket of a nut runner.

[0002]

2. Description of the Related Art For example, in a vehicle tire assembling apparatus, an assembling robot attaches a tire to an axle and then fastens a nut using a nut runner to assemble the tire. In this case, the nut runner receives the nut held at a predetermined position, moves to the assembly position, and fastens the nut. Therefore, the nut retention device must retain the nut for easy receipt by the nut runner. 9 (a), 9 (b) and 9 (c) schematically show a conventional nut holding device.

The nut holding device 101 shown in FIG.
A guide pin 103 having a tapered shape is integrally formed on the upper portion of the support shaft 102 via a step portion 104. Nut 10
Has a tapered surface 10a at one end,
The guide pin 103 is inserted into b and is mounted and held on the step portion 104. Therefore, in this way, the nut holding device 10
The socket 201 of the nut runner approaches the nut 10 held by No. 1, the tip of the socket 201 is pressed against the nut 10 and the socket 201 is rotated, and the phase of the nut 10 and the holding hole 202 of the socket 201 is changed. When fitted, the nut 10 fits into the holding hole 202 and is transferred to the socket 201.

Further, a nut holding device 11 shown in FIG. 9 (b).
1 is a guide pin 1 having a tapered shape on the upper portion of the support shaft 112.
13 is integrally formed via a step portion 114, and has a pair of claws 115 for holding the outer shape of the nut 10 by an air cylinder (not shown). Nut 10 has screw hole 1
The guide pin 113 is inserted into 0b and placed on the step 114,
In addition, the pair of claws 115 are held by gripping the outer shape. Therefore, the socket 201 of the nut runner approaches the nut 10 held by the nut holding device 111 as described above, the tip of the socket 201 is pressed against the nut 10, and the socket 201 is rotated to rotate the nut 10 and the socket 201. When the nut 10 is in phase with the holding hole 202, the nut 10 is transferred into the socket 201 by fitting into the holding hole 202 and releasing the holding by the pair of claws 115 at the same time.

Further, the nut holding device 12 shown in FIG. 9 (c).
In the first embodiment, a pair of collets 123 each having a tapered tip end portion are integrally formed on a support shaft 122 via a step portion 124, and an operating shaft 125 is movably supported in the support shaft 122. A pressing portion 126 capable of widening the diameter of the collet 123 is formed in the. The nut 10 is held by the collet 123 being inserted into the screw hole 10b, being placed on the step portion 104, and the pressing portion 126 of the operating shaft 125 widening the diameter of the collet 123 and being pressed against the screw hole 10b. Therefore, with respect to the nut 10 held by the nut holding device 121 as described above, the socket 201 of the nut runner
Approach, press the tip of the socket 201 against the nut 10 and rotate the socket 201, and when the nut 10 and the holding hole 202 of the socket 201 are in phase,
The nut 10 is fitted into the holding hole 202, and at the same time, the operation shaft 125 is lowered to release the pressure contact by the collet 123, so that the nut 10 is transferred to the socket 201.

[0006]

However, in the above-mentioned conventional nut holding devices 101, 111, 121, there is a problem that the nut is not damaged and cannot be properly supplied to the socket.

That is, in the nut holding device 101, the nut 10 is held by inserting the guide pin 103 into the screw hole 10b, and is not rotated. Therefore, when the nut runner socket 201 is rotated while being pressed against the nut 10, the nut 10 will be
1 and the nut 10 and the socket 20
It is difficult to fit the first holding hole 202.

In the nut holding device 111, the nut 10 is held by the guide pin 113 inserted into the screw hole 10b and the pair of claws 115 holding the outer shape. Therefore, when the nut runner socket 201 rotates in a state of being pressed against the nut 10, the nut 10 causes the nut 10 to move.
5, the nut 10 is fitted in phase with the holding hole 202 of the socket 201. At the same time as this fitting, the grip by the pair of claws 115 is released. However, it is difficult to simultaneously fit the nut 10 and the holding hole 202 of the socket 201 and release the grip by the claw 115. When the release of the grip of the nut 10 by the claw 115 is delayed, the claw 115 is released. There is a problem that rubbing occurs between the nut 10 and the nut 10 and damages the outer peripheral surface of the nut 10.

Further, in the nut holding device 121, the nut 10 is held by inserting the collet 123 into the screw hole 10b and expanding the collet 123. Therefore, when the socket 201 of the nut runner is rotated in a state of being pressed against the nut 10, the nut 10 will collet the collet 123.
The nut 10 is engaged with the holding hole 202 of the socket 201 in phase with each other. Simultaneously with this fitting, the diameter of the collet 123 is reduced to release the pressure contact. However, the nut 10 and the socket 201
It is difficult to perform fitting with the holding hole 202 and releasing the pressure contact of the collet 123 at the same time, and when release of the pressure contact of the nut 10 by the collet 123 is delayed, the collet 123 and the nut 10 are released. Rubbing causes nut 10
There is a problem that the screw hole 10b of 1 is damaged. Further, the collet 123 does not have sufficient durability and may be damaged when a large force is applied.

The above-mentioned nut holding devices 101,
In addition to 111 and 121, for example, actual development Sho 63-1313
There is one disclosed in Japanese Patent Publication No. 30. In the one disclosed in this publication, the nut inserted into the guide pin is directly urged from the outside by a roller attached to the lever, so that the nut is stopped and held. However, in this device, since the roller is directly in pressure contact with the nut from the side of the nut, it is difficult to insert the nut into the guide pin, and the nut may be slanted to cause misalignment. There is. Further, since the rotation preventing mechanism including a lever and a roller is provided on the outer peripheral side of the nut pin, the device becomes large in size, an extra space is required, and there is a possibility that it may interfere with peripheral devices.

The present invention solves such a problem, and an object of the present invention is to provide a nut holding device capable of reducing the size and weight of the nut and securely holding the nut without damaging the nut. To do.

[0012]

SUMMARY OF THE INVENTION In order to achieve the above object, a nut holding device of the present invention has a guide pin projecting from a table in a screw hole of a nut and having the same center as the guide pin. And a rotation resistance member that rotatably supports the nut holder, on which the outer peripheral surface of the nut can be fitted and removed, and which applies a rotation resistance force to the nut holder from the lower surface side of the nut holder. It is characterized by.

Further, in the nut holding device of the present invention, a plurality of concave portions arranged at equal intervals in the circumferential direction are formed on the lower surface of the nut holder, and the rotation resistance member is one of the concave portions of the nut holder. It is characterized in that it is a plunger having a spring-biased ball to be pressed against one another.

[0014]

The nut is held on the table by inserting the guide pin into the screw hole and contacting the nut holder with the outer peripheral surface. When the socket is pressed against the nut and rotated in this state, the nut rotates along with the contact resistance with the socket, but the rotation resistance force is applied to the nut holder by the rotation resistance member, so it does not rotate along with the nut. It has stopped. Then, when the nut rotates with respect to the nut holder and the phases of the two match, the nut fits into the nut holder. Then, since the rotation resistance force is applied to the nut holder by the rotation resistance member, the rotation of the nut is stopped, the socket and the nut rotate relative to each other, and when the phases of the socket and the nut match, the outer peripheral surface of the nut is It fits into the socket and is retained. After that, the socket continues to rotate, but the nut holder in which the nut is fitted overcomes the rotation resistance member and rotates, so that the nut and the nut holder are not loaded and the nut is not damaged.

Since the rotation resistance member applies a rotation resistance force to the nut holder from the lower surface side of the nut holder, the rotation resistance member can be arranged below the nut holder, and the device can be made compact. Also, since the rotation resistance member prevents the nut from rotating through the nut holder,
The installation of the rotation resistance member does not make it difficult to insert the nut, and the nut does not become slanted.

In addition, a plurality of recesses are formed on the lower surface of the nut holder at even intervals in the circumferential direction, and the rotation resistance member is a plunger having a spring-biased ball so as to press into contact with one of the recesses. Since the resistance member can be unitized, the structure can be made compact, and at the same time, the rotation resistance can be controlled by the rotation force of the ball over the recess, so that stable rotation resistance can be imparted.

[0017]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a cross section of a nut holding device according to an embodiment of the present invention, FIG. 2 is a schematic view of a nut holder used in this nut holding device, and FIG. 3 is a tire to which the nut holding device of this embodiment is applied. Schematic of the assembling device, FIG. 4 is a plan view of the nut holding device attached to the nut feeder, and FIGS.
An outline of the nut passing operation is shown in FIG.

In the embodiments described below, the nut holding device of the present invention is mounted on the nut feeding device of the tire mounting device. As shown in FIGS. 3 and 4, the articulated work robot 11 is adjacent to a tire assembly line (not shown).
And a hand 13 is attached to the tip of the work arm 12 of the work robot 11. A tire gripping mechanism 14 is attached to the hand 13 and
A plurality of nut runners having sockets 15 are mounted. Then, the tire 16 is provided close to the work robot 11.
Supply line 17 is provided. Further, the work robot 11 is provided with a nut feeder 18, and a table 20 is rotatably attached to a tip end portion of an arm 19 of the nut feeder 18, and four nut holding devices are provided on the table 20. 21 is attached so that the supplied nut 10 can be held.

The four nut holding devices 21 have substantially the same structure. As shown in FIGS. 1 and 2, a support shaft 23 is axially movable in a through hole 22 formed in the table 20. A guide pin 25 having a tapered tip is fitted on the support shaft 23 via a step portion 24.
Are fixed together. The guide pin 25 can be inserted into the screw hole 10b of the nut 10 to support the nut 10. The lower part of the support shaft 23 is connected to a drive device (not shown).
The nut 10 supported via the can be moved upward.

On the table 20, the table 2
A nut holder 27 is rotatably guided and supported by a ring-shaped bracket 26 fixed to 0, and the bracket 26 is engaged with the outer peripheral edge of the nut holder 27 from above to prevent the nut holder 27 from tilting from the table 20. To prevent. The nut holder 27 has a ring shape, is supported by the bracket 26 with a minute gap, and is rotatably supported by the same central axis as the guide pin 25. The nut 1 is attached to the inner peripheral surface of the nut holder 27.
A fitting portion 28 is formed as a recess conforming to the outer shape of 0, and a plurality of slits 29 are formed on the lower surface at equal intervals in the circumferential direction along the radial direction. On the other hand, a plunger 30 is attached to the table 20 below the nut holder 27, and a ball 31 to which a biasing force is applied by a spring provided inside is elastically pressed against the lower surface of the nut holder 27. The plunger 30 is engaged with one of the slits 29 and applies a predetermined rotation resistance force to the nut holder 27.

Reference numeral 32 is a photoelectric detector for detecting the presence or absence of the nut 10, and 33 is a hole for removing dust formed in the table 20. Further, the socket 15 has a holding hole 1 at the tip.
5a, and the nut 10 in the holding hole 15a.
A magnet 15b for adsorbing is attached.

Therefore, in order to assemble the tire 16, as shown in FIGS. 1 and 2, the tire 16 is conveyed along the supply line 17, while the nut feeder 18 is mounted on the table 20 via the arm 19. Each nut holding device 21
The nut 10 is supplied to. The work robot 11 operates the hand 13 via the work arm 12 to grip the tire 16 by the tire gripping mechanism 14, while the socket 15 of the nut runner receives the nut 10 held by the nut holding device 21.

At this time, as shown in FIG.
Is held by the guide pin 25 being inserted into the screw hole 10b and the tapered surface 10a coming into contact with the nut holder 27. In this state, as shown in FIG. 5, when the socket 15 is lowered and the tip portion is pressed against the nut 10 to rotate, the nut 10 is in surface contact with the socket 15 and is rotated by the frictional resistance. Since the ball 31 of the plunger 30 is locked in the slit 29 on the lower surface of the nut holder 27 to give a rotational resistance force, the nut holder 27 is stopped without rotating together with the nut. When the nut 10 rotates together with the socket 15 by a predetermined angle, the nut 10 is rotated by the nut holder 27 as shown in FIG.
And the outer peripheral surface fits into the fitting portion 28 of the nut holder 27.

Then, the nut 10 is held by the nut holder 27 whose rotation is restricted by the plunger 30, and the socket 15 rotates against the frictional resistance force with the nut 10, and as shown in FIG. Socket 15 and nut 1
The outer peripheral surface of the nut 10 is fitted into the holding hole 15a of the socket 15 in phase with 0. Even if the nut 10 is held by the socket 15 as described above, the socket 15 rotates slightly, but the rotation of the socket 15 is absorbed by the nut holder 27 overcoming the resistance force of the plunger 30 to rotate,
Load may be applied to the nut 10 or the nut holder 27,
The nut 10 is not damaged.

After that, as shown in FIG.
Is stopped, and the support shaft 23 is moved upward by the drive unit to push up the nut 10 held by the guide pin 25, and the nut 10 is pulled out from the nut holder 27. Then, when the socket 15 is raised, the nut 10
The magnet is held in the holding hole 15a by the magnet 15b, and thus is transferred from the nut holding device 21 to the socket 15 (nut runner).

When the nut runner socket 15 receives the nut 10 from the nut holding device 21 as described above, FIG.
2, the work robot 11 operates, the gripped tire 16 is mounted at a predetermined position, and then the nut runner operates and the nut 10 held by the socket 15 is fastened to a bolt (not shown) to fix the tire 16. To do.

Although the nut holding device of the present invention has been applied to the tire assembling device in the above embodiment, the description has been made.
The scope of application is not limited to this. Further, in the above-described embodiment, the nut 10 having the tapered surface 10a is used, but a normal nut may be used. Furthermore, the nut holder 2
Although the plunger 30 is used as the rotation resistance member that applies the rotation resistance force to the member 7, a leaf spring or the like may be used, and in addition, one plunger 30 is used, but a plurality may be used.

[0029]

As described above in detail with reference to the embodiments, according to the nut holding device of the present invention, the guide pin which can be inserted into and removed from the table is projected from the table and the guide pin Since the nut holder that has the same center and the outer peripheral surface of the nut can be freely inserted and removed is rotatably supported on the table, and the rotation resistance member that gives the rotation resistance force to this nut holder is provided, the rotation resistance member The nut holder to which force is applied is prevented from rotating until the nut is fitted, and after fitting, it will overcome this rotation resistance force and rotate, so that the nut can be held securely without damaging the nut. In addition, it is possible to reduce the size and weight of the device itself, and the workability is not hindered by the difficulty of inserting the nut and the diagonal inclination of the nut.

According to the nut holding device of the present invention,
Since a plurality of recesses are formed on the lower surface of the nut holder at even intervals in the circumferential direction and the rotation resistance member is a plunger having a spring-biased ball to press into contact with one of the recesses, it is possible to promote downsizing of highlands. At the same time, stable operation can be obtained, and durability and reliability can be improved.

[Brief description of drawings]

FIG. 1 is a sectional view of a nut holding device according to an embodiment of the present invention.

FIG. 2 is a schematic view of a nut holder used in the nut holding device.

FIG. 3 is a schematic view of a tire mounting device to which the nut holding device of the present embodiment is applied.

FIG. 4 is a plan view of a nut holding device attached to a nut feeder.

FIG. 5 is a schematic diagram showing a nut delivery operation.

FIG. 6 is a schematic diagram showing a nut delivery operation.

FIG. 7 is a schematic diagram showing a nut delivery operation.

FIG. 8 is a schematic diagram showing a nut delivery operation.

FIG. 9 is a schematic view showing a conventional nut holding device.

[Explanation of symbols]

 10 Nut 10a Tapered Surface 10b Screw Hole 15 Socket 15a Holding Hole 20 Table 21 Nut Holding Device 23 Support Shaft 25 Guide Pin 26 Bracket 27 Nut Holder 28 Fitting Part (Recess) 29 Slit 30 Plunger (Rotation Resistance Member)

Claims (2)

[Claims] 1. A nut holder is provided on a table, the guide pin projecting from a table so that the nut can be inserted into and removed from the threaded hole of the nut, and the outer peripheral surface of the nut can be inserted into and removed from the table. A nut holding device comprising a rotation resistance member that is rotatably supported and that applies a rotation resistance force to the nut holder from a lower surface side of the nut holder. 2. The nut holding device according to claim 1, wherein a plurality of concave portions arranged at equal intervals in a circumferential direction are formed on a lower surface of the nut holder, and the rotation resistance member is a concave portion of the nut holder. Is a plunger having a ball that is spring-biased so as to come into pressure contact with one of the nuts.