JPH07246528A - Chuck for fastening device for fastening member - Google Patents

Abstract

PURPOSE:To make the whole of a fastening device in occupied space in the vertical direction. CONSTITUTION:Paired rocking members 2 are installed at the lower section of a feed member 1, the locking members 2 are supported in such a way that they can be rocked by the use of paired shaft members 17 which, are directed to the radial direction while their axial lines are located on a split surface 9, and they are energized by an elastic member 19 to the normally closed direction. Therefore the lower end sections of the rocking members 2 is widened so as to be opened upward beyond a closing position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chuck for a tightening device for automatically tightening a fastening member such as a bolt by using a nut runner or the like.

[0002]

2. Description of the Related Art In a tightening device for automatically tightening a bolt, it is necessary to use a bolt chuck to hold the bolt so that the posture of the bolt is not disturbed during tightening by a nut runner or the like. A conventional structure of a bolt chuck used for such an application is shown in FIGS. 4 and 5.

As shown, the bolt chuck (25) is
It is composed of a cylindrical supply member (27) connected to a supply source (not shown) of the bolt (26) and a pair of swinging members (29) pivotally attached to the lower end of the supply member (27). To be done. Each of the swing members (29) has a holding portion (30) in which a cylindrical conical body is divided into two in the vertical direction, and a substantially rectangular columnar shape which is provided upright on the peripheral portion of the upper surface of the holding portion (30). It is composed of a support part (31). A vertical notch (32) is formed in the lower end portion of the supply member (27) facing each other while leaving a thin wall. The notch (32) has a support portion for both swinging members (29). (31) is stored. Both swing members (29) are swingably supported with respect to the supply member (22) by a shaft member (34) horizontally inserted through the support portion (31) and the supply member (27), and the support portion is also supported. (3
A spring (35) interposed in a compressed state between the inner diameter surface of the upper end portion of 1) and the outer diameter surface of the notch (32) always urges it in the closing direction. In addition, the supply member (27) has four outer peripheral surfaces to secure a space for attaching and detaching the shaft member (34) at the time of maintenance and inspection.
A storage portion (36) is formed by cutting out a portion.

Both holding parts (30) (shown by the solid line) in the closed position have their end faces in close contact with each other, and the inner diameter part thereof has a conical guide surface (37) whose diameter is reduced downward. ) Has been formed.

The bolt (26) supplied from the supply source falls with the screw portion down in the cylindrical supply passage (39) formed in the inner diameter portion of the supply member (27), and the flange portion (26a).
Stops when touches the upper end of the guide surface (37).
After this, a nut runner socket (not shown) is inserted into the supply passageway (39) to engage with the head of the bolt (26), and the bolt (26) is lowered while rotating the socket to hold it. Shower fastening members (4
Screw it into 0). Both swinging members (29) are pushed apart (shown by a chain double-dashed line) as the bolt (26) descends, and when the flange portion (26a) passes through the lower opening (41) of the holding portion (30). The elastic force of the spring (35) elastically returns to the closed position (shown by the solid line).

[0006]

By the way, in the conventional bolt chuck, the shaft member (34) is provided at the upper ends of both of the oscillating members (29) formed to be tapered, and the oscillating member (29) is provided. All of the lower ends of () are located on the inner diameter side of the shaft member (34). Therefore, when the swinging member (29) in the closed position is opened, the lower end of the swinging member (29) moves in a region below the closed position and reaches the open position. In this case, when the show fastening member (40) is arranged near the lower end of the swing member (29), the lower end of the swing member (29) and the show fastening member (40) collide and interfere with each other. Therefore, in the conventional device, as shown in the drawing, the fastening member (40) is replaced with the swinging member (29).
Since there is no choice but to dispose a certain gap (42) from the lower end of the device, the space occupied by the entire device in the vertical direction increases.

Therefore, an object of the present invention is to reduce the space occupied by the entire tightening device in the vertical direction.

[0008]

[Means for Solving the Problems] To achieve the above object,
In the present invention, a plurality of swinging members each having a shape obtained by dividing a tubular body in the vertical direction, a supply member arranged above the swinging members, and an elastic member for biasing each supply member in the closing direction are provided. Each swing member is swingably supported by the supply member by the shaft member, and a guide surface that reduces in diameter downward is provided below the inner diameter surface of each swing member. In the one that elastically holds the outer diameter surface of the member, the shaft member is arranged in the radial direction with its axis located on the dividing surface between the adjacent rocking members.

As the fastening member, bolts, nuts or screws can be used.

[0010]

When the fastening member elastically held by the swing member is pushed down by the nut runner or the like, the swing member spreads around the shaft member while resisting the elastic force of the elastic member, and the fastening member is lowered. Tolerate. Throughout the entire descending process, the guide surface of the swing member comes into contact with the outer diameter surface of the fastening member to provide smooth guidance. In the present invention, since the shaft member is provided in the radial direction with the axis of the shaft member located on the dividing surface between the adjacent rocking members, the lower end portion of the rocking member is the same vertical surface as the shaft member. It is located above or on the outer diameter side. As a result, the lower end portion of the swinging member expands above the closed position with the closed position as the lowermost position, so that the swinging member can be arranged close to the lower end portion of the swinging member. And there will be no collision or interference between the fastening members.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a bolt tightening device will be described below with reference to FIGS.

As shown in FIGS. 1A and 3, this tightening device has a cylindrical supply member (1) similar to the conventional device.
And a bolt chuck (3) including a pair of swing members (2).

The supply member (1) is fixed to a lift table (4) which can be moved up and down. The center of the supply member (1) is larger than the outer diameter of the flange portion (5a) of the bolt (5). A feed passage (6) having a slightly larger inner diameter is formed. A pair of small-diameter holes (7) communicating the outer diameter surface and the supply passage (6) are formed at opposite positions passing through the diameter of the supply member (1) with their axes parallel to each other.

The two rocking members (2) are, as shown in FIG.
It has a shape in which a cylindrical body whose diameter is gradually reduced downward is bisected in the vertical direction. A semi-circular hole (10) having a semi-circular cross-section is formed in the upper part of both split surfaces (9) of one swing member (2).
Is formed, and the semicircular hole (10) cooperates with a semicircular hole (10 ') similarly provided on the other swing member (2) to form a large diameter hole (11) having a circular cross section. Make up. The inner diameter surface of the upper end portion of the swing member (2) is a tapered surface (12) having a large diameter on the upper end side to prevent interference with the supply member (1) when opening and closing.

A guide surface (14) is formed on the lower inner diameter surface of both rocking members (2) so that the diameter gradually decreases downward.
Both guide surfaces (14) are formed in a shape capable of making line contact with the outer diameter surface of the flange portion (5a) of the bolt (5) at any height. That is, as shown in FIGS. 1 (b) to 1 (d), the horizontal cross section of the guide surface (14) draws an arc having a radius of curvature (r) equal to the radius of the flange portion (5a) at any height. . When both rocking members (2) are in close contact, the guide surface (1
The horizontal cross section of 4) forms a circle with the same diameter as the flange (5a) at its upper end. Further, the horizontal cross section below this forms a spindle-shaped cross section in which the divided surface (9) side is sharpened.
This spindle-shaped cross section becomes narrower as it goes below the guide surface (14).

The swinging member (2) having the above structure is shown in FIG.
As shown in (1), the small diameter hole (7) and the large diameter hole (11) are aligned and then fitted into the lower portion of the supply member (1).
The insertion hole (16) formed by the small diameter hole (7) and the large diameter hole (11) has a shaft member (17) formed in a stepped shaft shape according to the inner diameter dimension of the both holes (7) (11). Is inserted. As a result, the shaft member (17) is arranged in the radial direction with the axis of the shaft member positioned on the split surface (9) of both swing members (2).

After inserting the shaft member (17), the shaft member (17)
A retaining ring (18) is attached to the outer diameter surface of and the outer diameter surface of the supply member (1) from the surroundings. The retaining ring (18) prevents the shaft member (9) from coming off and the swinging member (2) from separating. Since the retaining ring (18) is not displaced even when the swinging member (2) swings, it is possible to mold the retaining ring (18) not only with an elastic material but also with an inelastic material. is there.

Reference numeral (19) is a ring-shaped elastic member, for example, a garter spring, mounted on the outer diameter surface of both swinging members (2). The elastic member (19) constantly applies elastic force in the closing direction to both swinging members (2).

With the above structure, the bolt supplied from the supply source (not shown) into the supply passage (6) falls inside the supply passage (6), and the flange portion (5a) is located at the upper end of the guide surface (14). Stop when it comes into contact with. Next, lower the nutrunner socket (not shown) to remove the bolt (5).
Push down while rotating the two swinging members (2)
Expand (indicated by a chain double-dashed line in FIG. 1). At this time, the lower end of the swinging member (2) moves upward with the closed position as the lowermost position. Therefore, the fastening member (2
Even if 0) is arranged close to or in contact with the lower end of the rocking member (2), there is no collision or interference between the rocking member (2) and the fastening member (20). Therefore, unlike the conventional device, there is no need to provide a gap between the lower end portion of the swinging member and the fastening member, and the space occupied in the vertical direction of the entire device can be reduced.

The present invention can be applied not only to the bolt tightening device described above, but also to other tightening members such as nuts and screws.

[0021]

As described above, in the device of the present invention, the shaft member for supporting the rocking member is provided in the radial direction with its axis located on the dividing surface of the adjacent rocking member.
The lower end of the swing member swings with its closed position as the lowermost position. Therefore, even if the fastening member is arranged close to or in contact with the lower end of the swing member, collision and interference do not occur between the swing member and the fastening member. Therefore, the space occupied in the vertical direction of the entire device can be reduced as compared with the case where a gap is provided between the lower end of the swinging member and the fastening member as in the conventional device.

[Brief description of drawings]

FIG. 1 (a) is a vertical sectional view of a device of the present invention,
(B) figure, (c) figure, (d) figure are sectional views in the BB, CC, and DD line in (a) figure, respectively.

FIG. 2 (a) is a bottom view of the rocking member closely attached,
7B is a cross-sectional view taken along line EE in FIG. 7A, and FIG. 7C is a cross-sectional view taken along line FF in FIG.

FIG. 3 is a sectional view taken along line AA in FIG.

FIG. 4 (a) is a side view of a conventional device, and FIG. 4 (b) is a cross-sectional view taken along line GG in FIG. 4 (a).

5A is a cross-sectional view taken along the line HH in FIG. 4A, and FIG. 5B is a cross-sectional view taken along the line I-I.

[Explanation of symbols]

 1 Supply member 2 Swing member 5 Bolt 5a Flange portion 9 Dividing surface 14 Guide surface 17 Shaft member 19 Elastic member

Claims (1)

[Claims] 1. A plurality of swinging members each having a shape obtained by vertically dividing a tubular body, a supply member arranged above the swinging members, and an elastic member for biasing each supply member in a closing direction. Each swing member is swingably supported by the supply member by the shaft member, and a guide surface that reduces in diameter downward is provided below the inner diameter surface of each swing member. In the one for elastically holding the outer diameter surface of the fastening member, the shaft member is provided in a radial direction with its axis located on a dividing surface between adjacent rocking members. Chuck for fastening device of fastening member.