JPH0748350Y2 - Centering device for fastening bolts and nuts - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] In this invention, when the bolts and nuts are fastened, the tips of the bolts and the screw holes of the nuts are centered (the axial centers are aligned. The device which makes the fastening smooth and reliable.

[Prior Art] Fastening of bolts and nuts may be automatically performed using a machine when the number of bolts and nuts is large or the working environment is poor. For example, Japanese Utility Model Laid-Open No. 63-113523 discloses an automatic fastening device that can be used for segment bolts in tunnel excavation work.

When performing such automatic fastening, the fastening itself is performed by turning a bolt or a nut by a rotating means, but prior to that, it is necessary to center the tip portion of the bolt and the screw hole of the nut. This is because if the axial center position is displaced, the two cannot be screwed (screwed together) even if they are rotated, or the screw thread is damaged. In fact, this kind of centering work is necessary when manually tightening bolts and nuts.In that case, the operator puts the end face of the nut in his hand on the tip of the bolt and moves the nut slightly. Screw the screw hole to the tip of the bolt and then turn the nut (or bolt). When holding the nut directly in the hand like this, it is possible to perform centering by unconsciously moving the tip of the hand, but it is necessary to take some technical measures to automatically center it with a machine. Was subject to the following conditions. That is, b) Method of sharpening the tip of the bolt in advance or enlarging the end of the screw hole of the nut to form a tapered surface there: Move the bolt or nut by an appropriate amount in the radial direction. If it is possible, the centering is automatically performed by this method. This is because if the bolt and the nut are brought into contact with each other at any tapered surface, then the axes are aligned along the tapered surface only by bringing the bolt and nut close to each other.

B) A device in which a nut socket is mounted in a rotating member that rotates a nut so that the shaft center can move in parallel in the radial direction: the means described in the above-mentioned public relations, and Oldham for moving the shaft center of the socket. Insert joints. According to this device, the deviation of the axial center between the bolt and the nut is absorbed by the joint.

[Problems to be Solved by the Invention] The means (a) and (b) have the following problems, respectively.

First, in the case of (a) in which bolts and nuts are processed in advance, it is easy to carry out because it is a simple method, but when the number of bolts and nuts is large, the working cost increases due to the processing cost. For example, when this method is applied to the segment bolts or their nuts for the tunnel excavation work described above, the cost advantage cannot be expected to be large due to the large number.

On the other hand, with regard to the device in (b) where the socket is attached via the Oldham joint, etc., high precision parts such as the joint and a spring for holding the socket at the center of the rotating member while allowing the socket to move In short, the structure is complicated.

An object of the present invention is to provide a centering device for fastening bolts and nuts which does not require any special processing on the bolts and nuts and has a simple structure.

[Means for Solving the Problems] The centering device according to the first aspect of the present invention has the following a) with respect to the socket that holds the nut so as not to rotate relative to each other.
And b) are deployed. That is, a) a plurality of projecting pieces which are supported by a pin and can rotate around (reciprocating rotation within a certain range.
When projecting into the same path, the inner edge of each is inclined toward the screw hole of the retained nut.

b) pressing a part of each of the protrusions to keep the protrusion in the protruding state when the nut is held in the socket, and retracting the protrusion when the nut separates from the socket through the path. A spring that is arranged to be most compressed by the projection when it is between the protruding state and the retracted state in order to keep it.

Further, in the centering device according to the second aspect, the following a) and b) are provided for the socket that holds the nut so as not to rotate relative to each other. That is, a) a plurality of projecting pieces which are supported by pins and can rotate around (same as above) into and out of the nut insertion / removal path in the socket, and the front part of the retained nut. When the protrusions on the front side (the side closer to the bolt) and on the rear side (back side) project into the same path as the protrusions on the front side, the front inside toward the screw hole of the retained nut While the edge is tilted, the rear projection protrudes into the same path when the front projection retracts from the same path.

b) Engage with a part of each of the above-mentioned projecting pieces through a sphere pressed by a spring and a recess into which a part thereof enters, and when the nut is held in a socket, the projecting piece is provided with When the nut enters into the recess to keep it protruding into the path, and when the nut disengages from the socket through the path, the projection of the front part retracts and the projection of the rear part projects into the same path. A mechanism that allows the above-mentioned sphere to enter the dent in order to keep the above state.

[Operation] In the centering device according to claims 1 and 2 of the present invention, first, a nut is inserted into the socket to insert a nut a) (in the device according to claim 2, a front projection part. (Unless otherwise noted), each protrusion is kept in the protruding state as it is by the spring or mechanism of b) above when it is projected into the nut insertion / removal path. At that time, the inner edge of each protrusion inclines toward the screw hole of the held nut, and if each edge is connected by a surface (virtual curved surface), the funnel is placed in front of the nut toward the screw hole. It will be in a state similar to that.

Therefore, when the socket holding the nut and the bolt to be fastened are brought close to each other, the inner edge portion of the protruding piece in the protruding state hits the tip portion of the bolt, and the socket is guided according to the inclination of the edge portion, The screw hole position of the nut reaches the tip of the bolt (or the bolt is guided according to the inclination, and the tip of the bolt aligns with the screw hole of the nut).

After the bolts and nuts have been centered in this way, either the socket is turned, or the socket is fixed and the bolt is turned to complete the fastening of the two. This is because the held nut and socket do not rotate relative to each other, and this socket can be treated as the head of a spanner (a normal handheld spanner or a spanner for automatic fastening).

After the fastening is completed, when the socket is moved away from the bolt / nut (or the former is moved away from the latter), the nut is disengaged from the socket through the insertion / removal path. At this time, since the protrusion of a) is pushed by the nut and retracted from the same path by the mechanism of b), the detachment is not hindered by this protrusion.

The centering device of the invention is characterized in that the protruding piece retracted from the insertion / removal path when the nut is removed from the socket in this way is kept in the retracted state as it is. Therefore, it is easy to insert a new nut used for the next fastening into the socket. The reason why the projecting piece is kept in the protruding state in the insertion / removal path as described above and is also kept in the retracted state is as follows.

That is, first, in the case of the centering device of claim 1, the protrusion of a) is rotatably supported by the pin and a part of the protrusion is pushed by the spring of b). The spring is in the most compressed relationship when it is between the retracted state and the retracted state. Therefore, in order to bring the projecting piece in the retracted state into the projecting state, it is necessary to temporarily compress the spring on the way, and the projecting piece does not return to the projecting state even if no operation is performed. The reason why the protruding piece is kept in the protruding state as described above is that the spring needs to be compressed once while the protruding piece is moved from the protruding state to the retracted state.

On the other hand, in the case of the centering device according to claim 2, the projecting piece of a) has a projecting part at the front and rear parts, is rotatably supported by a pin, is pressed by a spring, and a sphere for it. Engages with the mechanism of b) having a recess. Then, in the above retracted state, that is, in the state where the front protrusion is retracted from the nut insertion / removal path, the spherical body enters the recess, and the projecting piece cannot freely rotate from the retracted state.
Therefore, the projecting piece is kept in the retracted state until the nut is inserted into the socket next time. When the nut is out of the socket, the front protrusion is retracted while the rear protrusion is protruding into the insertion / removal path, so when inserting a new nut into the socket through the same path. The projecting piece is pushed by the nut at the rear projection and pivots around the pin to displace to the projecting state (state where the front projecting section projects into the insertion / removal path), and in the same manner as above -It is kept in that state by the engagement (entry) between the depressions. Therefore, in the device according to the second aspect, when the nut is inserted into the socket, the projecting piece is naturally in the projecting state and kept in that state, while when the nut is taken out after the fastening is completed, the projecting piece is automatically retracted. The state is maintained, and the state is maintained until the next nut is inserted.

[Embodiment] As a first embodiment of the present invention, a detailed view of a centering device 10 is shown in FIG. 1, and a schematic view of a bolt / nut automatic fastening device using the centering device 10 is shown in FIG. . 1 (a) is a sectional view of the device 10 holding the nut A, FIG. 1 (b) is a sectional view of the device 10 separated from the nut A after fastening, and FIG. 1 (c) is the same part (a). ) Is a view taken along the line cc of FIG.

As shown in FIG. 1, the centering device 10 includes a socket 11 having a hexagonal hole 11a for holding the nut A, and three (or six) projecting pieces radially attached to the socket 11.
12 and a mechanism for supporting and moving the projecting piece 12. That is, the projecting piece 12 is rotatably attached to the socket 11 through the support pin 13 in the notch 11e, and the ring 14 and the compression piece 12 are compressed between the projecting piece 12 and the flange portion 11d of the socket 11. The coil spring 15 is interposed. Protrusion
When 12 rotates around the pin 13, the protrusion 12a at the tip of the pin 12 projects into and out of the socket 11, but its position is in front of the hexagonal hole 11a (left in FIG. That is, it corresponds to a path for inserting and removing the nut A (insertion and removal).
Further, when the projection 12a projects into the above-mentioned path as shown in FIG. 4A, the projection 12 has a taper inclination toward the screw hole of the nut A (however, the projection 12a is located inside the root diameter of the female screw). There is also an inner edge 12b which does not) and an outer end 12c which projects out of the socket 11. In FIG. 1, reference numeral 11c (the same figure (c)) is a mounting bracket for the support pin 13 formed integrally with the socket 11, and reference numeral 11b (the same figure (a)) is the bolt B passing through the nut A. Is the protruding space at the tip of the.

Due to the action of the spring 15, the protruding piece 12 has the outer end portion 12c.
Is pushed forward by the ring 14 (normally the socket 11 hexagon
(Including when the nut A is held in 11a) is maintained in the state of FIGS. 1 (a) and (c), while the pin 13 of the pin 13 is removed when the socket 11 is removed from the nut A fastened to the bolt B. By turning around, the protrusion 12a is retracted out of the path as shown in FIG. As is clear from the figure, the spring 15 has the protrusion 12a of the protrusion 12 as shown in FIG.
In the intermediate stage between the state of projecting into the path and the state of retracting as shown in FIG. 7B, the corners at the rear of the projecting piece 12 are most compressed and shortened. Since the protrusion 12 naturally receives a force from the compressed spring 15 in the direction in which it extends, when the protrusion 12 is in the protruding state as shown in FIG. 8A and as shown in FIG. When in the retracted state, each state will be maintained as long as no other force is applied. As shown in (a) and (c) of the same figure, when the socket 11 is brought close to the bolt B with the nut A attached, the inclined inner edge portion 12b of the protruding piece 12 touches the tip portion of the bolt B. Since the socket 11 is guided, the screw hole of the nut A is naturally aligned with the tip of the bolt B, and the nut A is centered with respect to the bolt B. The protruding portion 12a protruding as shown in FIG. 4A also has an effect of preventing the unfastened nut A from falling off from the socket 11.

The automatic fastening device of FIG. 2 is a device for automatically fastening the nut A to the segment bolt B for tunnel excavation work by utilizing such a centering function of the centering device 10. In the figure, symbols S1 and S2 are attached to the inner surface of the drill hole,
It is a segment assembled by fastening the bolt B and the nut A.

The overall structure of this automatic fastening device is as follows.
The above-described centering device 10 and a partially modified centering device 10 '
Of the booms 21 and 22 are arranged so as to face the tips of the booms 21 and 22, respectively.
It is slidably attached to 23a and is connected to a hydraulic cylinder (not shown) in the frame 23. The frame 23 is attached to the tip end support portion 42 of the moving arm 41 provided on the excavator (not shown) via the support shaft 43. As will be described later, a displacement absorbing mechanism (not shown) is provided between the frame 23 and the support shaft 43 in order to allow displacement of the axis of the centering device 10, 10 ', which allows the displacement. Based on the displacement being
On the other hand, some swing and parallel movement are possible.

The centering device 10 is the same as that shown in FIG. 1 and is fixedly arranged at the tip of the boom 21 via the support member 17. However, one centering device 10 'is provided with a pinion 19 outside the socket 11'. In addition, it is rotatably arranged at the tip of the boom 22 through a support 18 having a bearing (not shown) inside. A motor 31 is attached to the base of the boom 22, and the socket 11 'on the side of the device 10' rotates by using the motor 31 as a drive source and a power transmission mechanism (not shown). In addition, although not shown, in the vicinity of the lower portion of the boom 21, a delivery device (for inserting the bolt B, which pulls out the bolt B previously stored in the bolt storage hole u in the segment S2 for fastening and passes through the insertion hole v , Those that rotate and send out) are also deployed.

The automatic fastening device having the above structure is operated as follows. That is, the approximate position and orientation of the frame 23
Determined by the movement of 41, the respective tips of the booms 21, 22 provided with the centering devices 10, 10 'are put into the recesses t1, t2 of the predetermined segments S1, S2. A nut A is inserted and held in advance in each socket 11, 11 'of the centering device 10, 10'.

The bolt B previously put in the accommodation hole u is passed through the insertion hole v by the above-mentioned delivery device.

After aligning the positions of the sockets 11 and 11 'substantially on the axis of the bolt B, the hydraulic cylinders in the frame 23 are operated to bring the centering devices 10 and 10' together with the booms 21 and 22. As described with reference to FIGS. 1A and 1C, the screw hole of the nut A is guided to the tip portion of the bolt B by this, so that each nut A is accurately centered at both ends of the bolt B. . In this example, since the bolt B has almost no degree of freedom in moving the axial center in the radial direction,
Due to the action of the displacement absorbing mechanism between the 43 and the frame 23, the nut A
(In other words, the axial center position of sockets 11 and 11 ') is displaced.

Drives the motor 31 so that the socket 1 of the centering device 10 '
Turn 1 '. Since one socket 11 is fixed,
The nuts A at both ends are screwed into the bolts B, and the fastening is completed in due course.

The hydraulic cylinders in the frame 23 are reversely operated to separate the centering devices 10 and 10 '. At this time, the centering device
10 ・ 10 'is in the state shown in Fig. 1 (b), and smoothly separates from the nut A.

Next, a reference second embodiment in which a part of the technical idea of the present invention is diverted will be described with reference to FIG. FIG. 3 (a) is a sectional view of the centering device 60, and FIG. 3 (b) is a front view thereof. This centering device 60 has an extremely simple structure, but also has a centering effect between the bolt and nut, and minimizes the number of protrusions so that it can be retracted by hand when inserting the nut. Although it is made easier, it is not always sufficient because the protrusion is not naturally kept in the retracted state.

In this centering device 60, only two wide protruding pieces 62 that are key-shaped are attached to the socket 61 that holds the nut A1 in the hexagonal hole 61a, and the protruding portion 62a at each tip is the insertion / removal path of the nut A1. It is designed to appear inside. The projecting piece 62 is swingably supported on the bracket 61c of the socket 61 via a support pin 63, and an inner edge portion 62b having a conical surface shape is formed in the vicinity of its tip, and a rear end portion 62c and Locking piece of socket 61
A tension spring 64 is installed between the tension spring 64 and 61d.

Since the rear end portion 62c (inside the pin 63) is pulled by the spring 64, after inserting the nut A1 into the socket 61 (the same when not inserted), the protruding portion of the projecting piece 62 is as shown in the figure. 62
The a projects from the notch 61e at the front end of the socket 61 inward (in the insertion / removal path of the nut A1). In this state, the inner edge 62
b) is tapered toward the screw hole of the nut A1, so simply move the socket 61 forward toward the bolt B1,
The socket 61 is guided by the contact between the inner edge portion 62b of the protruding piece 62 and the bolt B1, and the nut A1 is centered with respect to the bolt B1.

After the fastening is completed by turning the bolt B1 or turning the socket 61 by the operation piece 68, the device 60 is separated from the nut A1 only by retracting the socket 61. Nut A1 is socket 61
This is because the protrusion 62a of the protrusion 62 withdraws to the outside of the socket 61 (upper and lower in the drawing; outside the insertion / removal path of the nut A1) against the force of the spring 64 when it is pulled out of the socket 61.

Next, FIG. 4 shows a third embodiment of the present invention. (A) of the drawing is a vertical cross-sectional view of the centering device 70. The upper half shows the state during centering, and the lower half shows the state after completion of centering and fastening. FIG. 2B is a sectional view taken along line bb of FIG.

In this centering device 70, the plurality of projecting pieces 72 are swingably supported by the pins 73 on the bracket 71c of the socket 71, but two projecting portions capable of sandwiching the hexagonal hole 71a of the socket 71 from the front and rear. In addition to 72a and 72c, an arcuate edge 72b is provided in front of the protrusion 72a, and recesses 72d and 72e are provided at two locations around the pin 73.

As shown in the upper half of FIG.
When mounted in the hexagonal hole 71a of 71, the edge 72b of the projecting piece 72 inclines toward the screw hole of the nut A2, and this edge 72b serves as a guide for centering. Therefore, the bolt B2 and the nut A2 are centered simply by bringing the socket 71 and the bolt B2 closer to each other. The bracket 71c of the socket 71
Sphere 74 pressed from the inside by screws 75 and springs 76
However, since the protrusion 72a is prevented from swinging by entering one of the recesses 72d, the protruding portion 72a is kept in a state of protruding in front of the nut A2, and the nut A2 is prevented from falling off the socket 71. There is.

Then, in the same manner as above, either turn the bolt B2 or turn the socket 71 with the operation piece 78 to complete the fastening, then
The device 70 is separated from the nut A2 simply by pulling 71. At this time, the nut A2 pushes the protrusion 72a forward, so that the protrusion 72 swings around the pin 73, and the ball 74 stops in the lower half state of FIG. To do. From this state, continue to attach the nut to be tightened next to the socket 71.
When inserted into the inside, the projection 72c at the back is pushed by the nut and the projection 72 swings, and the state shown in the upper half of FIG.

The three embodiments of the centering device of the present invention have been introduced above, but the device of the present invention is not limited to the automatic fastening device (not limited to the segment as in the first embodiment), but the spanner for manual fastening. It can also be applied to the head, etc. For example, the third
Hold the operation piece (68 or 78) shown in Fig. 4 and Fig. 4 by hand,
If you insert the nut into the socket (61 or 71) and then bring the device (that is, the head of the wrench) into contact with the tip of the bolt, you can easily perform centering and immediately start the fastening operation. . In that case, if a ratchet mechanism is interposed between the socket and the operation piece, the fastening can be performed more quickly.

[Advantages of the Invention] According to the centering devices of claims 1 and 2 of the invention, the centering between the two can be reliably and smoothly performed without any special processing on the bolts and nuts to be fastened. Therefore, for example, it is particularly effective when a large number of bolts (and nuts) such as segment bolts in tunnel excavation work are automatically fastened by a machine in an environment where it is difficult to center manually. Since each device does not use high-precision parts and has a simple structure, the device cost is low and it is hard to break down. Further, in the device of each claim, when the nut is detached from the socket, the projecting piece (or the projecting portion at the front part) retracted from the insertion / removal path is kept in the retracted state as it is, and therefore it is used for the next fastening. Easy to insert a new nut into the socket. In particular, in the device according to claim 2, when the nut is inserted into or removed from the socket, the projecting state and the retracted state are switched without any special operation. Improves the efficiency of a series of operations including putting out and fastening.

[Brief description of drawings]

1 and 2 relate to a first embodiment of the present invention. FIG. 1 is a detailed view of a centering device, and FIG. 2 is a schematic view of an automatic fastening device for a segment using the centering device. is there. 1 (a) is a cross-sectional view of the centering device holding the nut (more precisely, a cross-sectional view taken along the line aa in FIG. 1 (c)), and FIG. 1 (b) is the device after fastening. Is a sectional view in a state of being separated from the nut, and FIG. 7C is a view taken along the line cc of FIG. FIG. 3 relates to a second embodiment of the present invention, and FIG. 3 (a) is a sectional view of the centering device (more precisely, a in FIG. 3 (b)).
(A sectional view), and FIG. 6B is a front view thereof. FIG. 4 relates to a third embodiment of the present invention, and FIG. 4 (a) is a vertical cross-sectional view of the centering device. The upper half of the figure is during centering and the lower half is after centering and fastening. Represents a state. Further, FIG. 7B is a sectional view taken along line bb of FIG. 10 ・ 60 ・ 70 …… Centering device, 11 ・ 61 ・ 71 …… Socket,
12 ・ 62 ・ 72 …… Projection piece, 12b ・ 62b ・ 72b …… Inner edge, A
・ A1 ・ A2 …… Nut, B ・ B1 ・ B2 …… Bolt.

Claims (2)

[Scope of utility model registration request] 1. A device for centering a tip portion of a bolt and a screw hole of a nut before fastening, which is supported by a pin for a socket for holding a nut so as not to rotate relative to the socket. A plurality of projecting pieces that can be retracted into and out of the nut insertion / removal path in the socket by rotating around, and when projecting into the same path, the inner edge of each of them is directed toward the screw hole of the retained nut. A part of which is inclined, and b) When the nut is held in the socket, the projection is kept in the projecting state while pushing a part of each of the projecting pieces, and when the nut is separated from the socket through the path, In order to keep the piece in the retracted state, a spring arranged so as to be most compressed by the projecting piece when it is between the protruding state and the retracted state is provided, and a centering device for fastening bolts and nuts is characterized. . 2. A device for centering a tip portion of a bolt and a screw hole of a nut before fastening, which is supported by a pin for a socket holding a nut so as not to rotate relative to the socket. It is a plurality of projecting pieces that can be retracted into and out of the nut insertion / removal path in the socket by rotating around, and have projecting portions at positions that are the front part and the rear part of the held nut. When the protrusion protrudes into the same route, the inner edge of the front inclines toward the screw hole of the retained nut, while the front protrusion retracts from the same route, the rear protrusion protrudes from the same route. Which protrude into the inside, and b) engage with a part of each of the above-mentioned projecting pieces through a sphere pressed by a spring and a recess into which a part thereof enters, and when the nut is held in the socket, Keep the front projection protruding into the path When the nut enters the recess and the nut separates from the socket via the path, the projection is retracted and the projection on the rear part is kept protruding in the path. A centering device for fastening bolts and nuts, which is equipped with a mechanism that goes into the recess.