JPH0510314A - Clamping method and device - Google Patents

Abstract

PURPOSE:To realize the fixation free from the position deflection by fixing both the members to be clamped and a coupling made of shape memory allay by each clamping mechanism and adjusting the position relation between both the members and the coupling so as to become proper and heating the coupling as it is. CONSTITUTION:Nipping holding parts 12a and 22a on one side of clampers 1 and 2 are formed longer than the nipping holding parts 12b and 22b on the other side, and cutting-in parts 14 and 24 for receiving a clamping member are formed inside. Grooves 16 and 26 are formed on the side surface with which the nipping holding parts 12a and 22a are opposed. A mark 0 showing the top edge positions of the clamping members P1 and P2 is drawn on the plane of the third clamper 4 so that a coupling J is temporarily fixed at the proper position for the clamping members Pi and P2 which are temporarily fixed by th8 clampers 1 and 2. Further, a cut-in part 5 is formed at the position corresponding to the proper coupling position, and fixed in the vicinity of the top edges of the nipping holding parts 12a and 22a. As for a heating mechanism 200, a frame body 7 is inserted along the grooves 16 and 26 after both the members P1 and the P2 and the coupling J are temporarily fixed, and fixed by heat at a constant position by the heating members 6a and 6b.

Description

Detailed Description of the Invention

[0001]

The present invention relates to members such as pipes and rods,
The present invention relates to a fastening method and a fastening device when fastening with a tubular shape memory alloy joint whose inner diameter shrinks due to heating.

[0002]

2. Description of the Related Art As one of methods for connecting members such as pipes and rods, the members are inserted into a shape-memory alloy joint formed into a tubular shape, and the joint is heated to a temperature higher than the shape-recovery temperature of the shape-memory alloy. There is a method of shrinking the inner diameter and fastening. The number of times the joint is heated depends on the type of shape memory alloy used, but generally the range of about 100 to 400 ° C. is common.

There are various heating methods for contracting the joint, and there are electric heaters (for example, Japanese Patent Laid-Open No. 2780/1990).
92) and electric heating (for example, Japanese Patent Laid-Open No. 2-27909).
A wide range of studies have been conducted, such as those utilizing the Japanese Patent No. 1). However, especially in the case of pipe connections, it is necessary that the connections be made in a short time in a limited space. In order to satisfy such conditions, the present inventors have previously proposed a joint heating device that employs an induction heating method with a high heating rate (Japanese Utility Model Laid-Open No. 20294/1990). According to this induction heating type joint heating device, even if the power source capacity is limited to about 1 kW which can use a 100 V outlet,
Fittings for size 15A pipes in 3 minutes in less than 1 minute
It is possible to heat to about 00 ° C.

By the way, when the members are fastened by the shape memory alloy joint, it is necessary to maintain the relative positional relationship between the two members to be fastened and the joint accurately. Except for special cases, it is desirable to shrink and fix the joint in a state where both members to be fastened are evenly inserted into the joint by half. In order to realize such an appropriate inserted state, in a normal fastening operation using a shape memory alloy joint, for example, an appropriate length portion to be inserted into the joint from the end surface of the member to be fastened is shown. It is common practice to mark the location to ensure that the required length of the member is inserted into the joint. Since such measures will depend entirely on the attention of the plumbing operator, they impose an undue mental burden on the operator and cannot be the final solution. Is clear. Moreover, even if the joint and the member are temporarily set at the proper position, it is apt to move from the normal position while being heated for fastening. In other words, no matter how carefully the worker performs the work, completely avoid the inconvenience that the joint shrinks and fixes both members at a position offset to the two members to be fastened. Was impossible.

If it is possible to find that the joint is greatly deviated from the proper position and the appearance of the fastening portion is abnormal, it is possible to redo the fastening of that portion, but if the position shift is slight, it is apparent. Above all, there is a possibility that the fastening is mistaken for normal. If such a defective fastening part is overlooked without being found, piping will start to be used and internal pressure will be applied and leakage will occur, so it will be installed not only in the piping system but also in the surrounding area. There is always the worry of developing into a very serious situation that causes major damage to existing equipment and the entire building.

The shape memory alloy joint essentially needs to be made larger than the member to be fastened, such as a pipe or rod, and was inserted into the joint before being heated and contracted. It is unavoidable that the member has room for movement inside the joint. Moreover, it is not possible to confirm from outside the position of the tip of the member once inserted into the joint. To ensure the proper insertion length, mark the member before inserting,
The only practical means is to make sure that the mark is correctly inserted. However, even with such consideration, as described above, it is not possible to prevent the position of the joint from moving during the subsequent heating operation.

As a method for avoiding displacement of the joint during heating, a groove is provided on the inner surface near the end face of the shape memory alloy joint to incorporate a temporary fixing ring, and a pipe member is used when the pipe is inserted into the joint. A proposal has been made to have a role of temporarily fixing the joint (Japanese Patent Laid-Open No. 2-286991). However, this joint is a temporary fixing ring that is unnecessary only once the pipe is fixed by the original shrinkage force of the shape memory alloy once assembled, and is incorporated only for temporary temporary fixing, which reduces the manufacturing cost of the joint. The current situation is that it has not been widely accepted because it will increase significantly.

[0008]

As described in the previous section,
When fastening a member such as a pipe or a rod with a shape memory alloy joint, it is necessary that the joint to be used is heated while being kept in a proper position with respect to the two members to be fastened. Also, the consideration for maintaining the proper position of the joint during heating is taken care of by the device side used for heating, not by the method of adding as a function of each joint side as already proposed. If you can
It seems that it is possible to achieve the aim at low cost. An object of the present invention is to provide a heating device for heating a shape memory alloy joint with a function of completely positioning and temporarily fixing a member such as a pipe or a rod to be fastened and the joint. A fastening method and device are provided.

[0009]

According to the present invention, two members, such as a pipe and a rod, are manufactured so that an inner diameter smaller than an outer diameter of the two members is stored in advance and then the member is inserted so that the member can be inserted. When using a shape memory alloy joint, the two members are temporarily fixed by a first clamper and a second clamper that are separated by a predetermined distance, and the relative positions of the two members are temporarily fixed. By temporarily fixing the joint with a third clamper for specifying the relationship and temporarily fixing the joint, and then heating the joint by housing a heating device between the first clamper and the second clamper. A fastening method, characterized in that the joint inner diameter is contracted to fasten the two members, and an apparatus for fastening a shape memory alloy joint for connecting the two members such as a pipe and a rod. A clamp mechanism for positioning and temporarily fixing each of two members such as a rod and a joint and a heating mechanism for heating the joint, and the clamp mechanism temporarily fixes the member on one side to be fastened. A portion corresponding to a proper position of the joint, which is composed of a second clamper for temporarily fixing the other member to be fastened to the clamper, and a connecting member for holding the first clamper and the second clamper at a predetermined interval. It has a third clamper which has a notch in it and is movable between two positions, a standby position and a joint fixed position, and the heating mechanism is detachably accommodated between the first and second clampers of the clamp mechanism. A fastening device characterized by the above.

However, in the above-mentioned device, at least one of the first and second clampers is provided with a stopper against which the joint end surface abuts, thereby positioning and temporarily fixing the joint.
As an embodiment having a function as a clamper and a method of combining a heating mechanism with a clamp mechanism, a method of inserting the heating mechanism along a groove provided on the side of the clamp mechanism, and a first and second heating mechanism. The heating unit may be configured to be openable and closable, and may be combined with the clamp mechanism in an open state and then heated in a meshed state. Further, as a heating method of the heating mechanism, a resistance wire heating method, an induction heating method, or the like, which is configured so that the existing method can be combined with the clamp mechanism as a split method such as splitting, can be used. As a heating method, it is possible to adopt a method of directly energizing the joint to generate heat, but in this case, the portion that directly contacts the fastening member such as the clamper or the joint is made of an electrically non-conductive material. , It is necessary to take care so that electricity does not escape.

[0011]

The present invention will be described below with reference to FIG. 1 showing an example of the apparatus of the present invention and FIG. 2 showing an example of a concrete method of fastening a joint using the apparatus. In order to securely fasten members such as pipes and rods with the shape memory alloy joint, assuming that the members may be fastened in the vertical position, first, the proper position of one of the reference members is set to the fastening device. It is effective to integrate the fastening device itself with one member by temporarily fixing it with one of the clampers. As a result, the position at which the other member is to be clamped and the position at which the joint is to be arranged can be determined with reference to the position of the member temporarily fixed by the clamper. One means for realizing such an idea is the clamp mechanism 100 in the apparatus of FIG. 1 and 2 are clampers for temporarily fixing each of the two members to be fastened. Both clampers are configured so as to be integrated via the connecting member 3. Each clamper has sandwiching portions 12a and 22a provided with notches 14 and 24 for stably receiving the members, and means 11 and 21 for temporarily fixing the members at positions opposed to these (here, in the case of a screw type, as an example). And a holding member 12b, 22b having a mark (1), and a mark 0 is provided on the connecting member 3 to indicate the position of the tip of the member. In the example of FIG. 1, the third clamper 4 for clamping the joint at an appropriate position is separated from the main body 100 of the clamp mechanism, but this is set as a standby position at a part of the clamp mechanism 100. Naturally, it is also possible to mount the joint fixed position so as to be reciprocally movable to form an integrated structure. In addition, the heating mechanism shown by 200 in the figure is one in which a resistance wire heater is molded to have a two-part structure, and after the clamp mechanism 100 temporarily fixes the member and the joint at appropriate positions,
It is configured to be used in combination so as to wrap the joint portion between the two clampers.

Next, a specific procedure of the fastening method will be described with reference to FIG. FIG. 2A shows one member P1 to be fastened to the side of the clamper 1 (referred to as a first clamper).
Is aligned and the fixing screw 11 is tightened to be temporarily fixed. The tip position of the member is determined based on the mark 0 written on the connecting member 3. FIG. 2B shows a state in which the joint J is inserted into the member P1. This shows the most basic step, and in practice, it is also possible to insert the joint J into the member P1 in advance and then set it on the clamper 1. In addition, although the tip of the member P1 is hidden by inserting the joint in the figure, it may be preferable to insert the joint deep enough to expose the tip of the member.

FIG. 2C shows a state in which the other member P2 is temporarily fixed by the fixing screw of the clamper 2 (referred to as a second clamper). If the joint J is only slightly inserted into the member P1 in the previous step, it is possible to insert the tip into the joint when positioning the member P2. In this example, the joint J is shown inserted into the P1 side first, but it is exactly the same even if the joint J is inserted into the P2 side and set.

FIG. 2D shows a state in which the joint is moved laterally and positioned at an appropriate position by the third clamper 4. After that, the heating mechanism 200 is set on the joint (FIG. 2 (e)) and electricity is applied, whereby the joint J contracts and the members P1 and P2 are fastened. In the above example, the tip position of the member to be clamped first among the members to be fastened is
The case has been explained in which the operator temporarily adjusts and fixes the sign based on the sign on the clamper. This sign is shown in Figure 3.
It is also possible to configure it as a projection shape that functions as a stopper at the tip of the member when necessary, such as 0 '.
The protrusion 0'is usually placed at the standby position as shown in FIG. 3A, and immediately before the first member is temporarily fixed by the clamper 1, it is pulled out to the position as shown in FIG. As described above, if the tip of the member P1 is brought into contact with this to perform positioning, more reliable work becomes possible. After the temporary fixing of the member P1 is completed, the projection 0'is returned to the standby position again, and the joint J is inserted into P1 (FIG. 3 (d)).
The members P1 and P2 can be fastened through the steps after (C).

Some of the shape memory alloy joints have a stopper for hitting and positioning the tip of the inserted member at the center of the inner surface of the joint. Even when such a joint with a stopper is used, it is not impossible to proceed with the work in the same manner as in the above case, but as shown in FIG. 4, the two fastening members P1 and P2 are preliminarily outside the clamp mechanism. It is also possible to insert into the both ends of the joint J and to set it in the clamp mechanism with the member and the joint combined. In this case, if force is applied lightly from both sides of the member so that the tips of both members P1 and P2 reach the contact stop J1 on the inner surface of the joint surely, the positional relationship between the member and the joint is automatically normal. Be kept in good condition. Therefore, the third clamper does not necessarily have to be used to position the joint, but in order for the joint to be set in the proper position with respect to the heating mechanism, the joint is placed in a proper position in the clamper. Since it is necessary, it is necessary to temporarily fix both members after adjusting the joint by moving the joint (or the clamper side) so that the third clamper comes to a position where the joint can be clamped.

[0016]

【Example】

Example 1 The apparatus shown in FIG. 1 is already one of the examples having the most basic functions of the present invention, but here, as a practical apparatus capable of reliably carrying out the method of the present invention, A specific example shown in FIG. 5 will be described. The device consists of a clamping mechanism shown as 100 and a heating mechanism shown as 200. The clamp mechanism 100 is made of a first clamper 1 and a second clamper 2, a connecting member 3 for holding these two clampers at a predetermined interval, and a heat-resistant insulating plate movably fixed to the two clampers. Third clamper 4
It consists of and. The third clamper needs heat resistance because it approaches the joint to be heated. However, in the first embodiment, since the heating mechanism is an induction heating system as described later, in order to prevent direct heat generation due to induction, Furthermore, it is made of a hemit board that also has insulation performance.

The first clamper 1 has grip portions 11a and 11a.
When grasping b, the other side holding portion 12b which opposes to the one side holding portion 12a in the front end direction moves as shown by the arrow, and the one side member P1 placed between the two can be held. it can. Similarly for the second clamper, the grip portion 2
When grasping 1a and 21b, the other side holding portion 22b that opposes the holding portion 22a moves, and the other side member P
2 can be clamped. Reference numerals 13 and 23 are knobs for adjusting the clamping force. In this clamp mechanism, the clampers 1 and 2 have one-side clamping portions 12a and 22.
a is formed to be longer than the tips of the other side holding portions 12b and 22b by a predetermined length, and notches 14 and 24 for receiving the fastening member are provided inside thereof. Reference numerals 16 (not shown because they are hidden in the drawing) and 26 are grooves formed on the side surfaces facing the one side holding portions 12a and 22a, which is one of the features of the apparatus of this embodiment. Will be described later.

The third clamper 4 plays a role of temporarily fixing the joint at an appropriate position with respect to the fastening member temporarily fixed by the first and second clampers. A mark 0 for clearly indicating the tip position of the fastening member is written on the plane, and a shallow cut 5 is provided at a position corresponding to the proper joint position.
Is formed, and is fixed near the tips of the one-side sandwiching portions 12a and 22a of the first and second clampers so as to be movable in two states, a standby state and a joint fixed state.

FIG. 5 already shows that one of the two members to be fastened is temporarily fixed to P1 by the first clamper, the other P2 is fixed by the second clamper, and the joint is temporarily fixed by the third clamper at the proper position. It represents the state. The process of temporarily fixing the fastening members P1 and P2 and the joint J up to this point can be performed in exactly the same manner as described above with reference to FIG. 2 except for the fixing means.

The heating mechanism 200 is a flat plate-shaped first conductor formed by embedding a spirally wound conductor in a heat-resistant and non-conductive material.
The heating unit 6a and the second heating unit 6b are composed of a U-shaped frame 7 and a handle 8 connected to the frame. The first heating portion 6a is fixed to the facing surface of the one side facing side 71a of the U-shaped frame body 7 via a heat insulating plate 9a, and the other side facing side 7
The second heating portion 6b is fixed to the facing surface of 1b via a heat insulating plate 9b. The first heating portion 6a and the second heating portion 6b are in a state of being divided into two by the connecting side 71c, but conductors (not shown) embedded in the respective heating portions 6a and 6b.
As described in detail in Japanese Unexamined Utility Model Publication No. 2-20294 mentioned above, the magnetic fluxes generated are connected to a circuit configuration in which currents strengthen each other, and power is supplied from a power source (not shown). There is.

The width of each of the one side facing side 71a and the other side facing side 71b of the frame is such that it can be inserted between the first clamper 1 and the second clamper 2 of the clamp mechanism 100. The groove 16/26 provided in the holding portion of the clamp mechanism, which has not been described above, is used. The rising portion 81 of the handle 8 of the heating mechanism 200 is provided to regulate the stop position when the heating mechanism 200 is inserted into the clamp mechanism 100 and moved forward. The heating mechanism 200 is provided with a temperature measuring device 9 for grasping the heating temperature for fastening, and the tip of the detector S (here, a thermocouple) applies a constant pressing force to the joint to be measured. It is attached via a spring (not shown) to give.

The heating mechanism 200 is used after the clamp mechanism 100 temporarily fixes both members P1 and P2 and the joint J as shown in FIG. If the rising portion 81 provided on the handle 8 of the heating mechanism 200 sufficiently pushes the heating mechanism 200 until it abuts along the groove of the clamp mechanism 100, the first and second heating portions 6a and 6b are to be heated by the joint J. It is automatically stopped at the proper position with respect to.

Embodiment 2 FIG. 6 shows another apparatus example which can surely carry out the method of the present invention.
Since the method of temporarily fixing the members to be fastened is the same as in the previous embodiment, the members and joints are not shown in FIG. 6, and only the device is depicted. The important points of the second embodiment different from the first embodiment are two points, that is, the part related to the third clamper that clamps the joint and the part related to the heating system of the heating mechanism. Add a description.

First, in the first embodiment, the integral third clamper movably attached to the tip of the one side clamping portion of the first clamper 1 and the second clamper 2 is divided into the first clamper 1 and the second clamper 1.
-The big difference is that it was fixed inside the second clamper as shown as 41 (hidden and not visible in Figure 6) and 42 in the figure. Along with this, the marker 0 indicating the reference position of the member tip on the third clamper in the first embodiment is changed to be displayed on the connecting member 3 in the second embodiment. Here, the inner rectangular length of the space sandwiched by the third clamper 41 and 42 divided into two is made so as to be almost equal to the length of the joint, so the first clamper should be fastened first. When one member is clamped by aligning the tip with reference to the mark 0, the tip of the third clamper 41 waits at a position corresponding to the insertion stop position when the joint is inserted into the fastened member. It becomes a form to do. Then, the joint is then inserted until it abuts on the third clamper 41, then the other member to be fastened is inserted into the joint, and then the member is clamped by the second clamper, and the member is fixed to the second clamper side. The part 42 of the third clamper is configured to hold one end of the joint so that it does not move, and can serve to temporarily fix the joint so as not to be displaced with respect to the member during heating.

Further, in the second embodiment, the heating mechanism is also changed, and instead of the induction heating method of the previous example, a band heater divided into two is used. That is, FIG.
6a and 6b correspond to the first heating unit and the second heating unit using the band heater, respectively. Also in this example, the first
Since the second heating portions are opposed to each other by the gripping handles 8a and 8b so as to be openable and closable, by combining the above-described clamp mechanism 100 so as to cover the joint portion in a state where the member and the joint are clamped at the proper positions. , The shape memory alloy joint can be heated to a specified temperature to shrink the inner diameter in a state where relative displacement between the member and the joint does not occur, and it is possible to stably obtain an appropriate fastening state. .

The heating mechanism has almost the same structure as that of the second embodiment, and it is also possible to adopt a method in which an electric current is directly applied to the joint portion to be heated to carry out heating by energization. The selection of the heating method such as induction heating, resistance heating, and electric heating can be freely performed in consideration of factors such as the size of the joint to be heated, the allowable working time, and the use environment.

[0027]

INDUSTRIAL APPLICABILITY According to the present invention, when a member such as a pipe or a bar to be fastened is inserted into a shape memory alloy joint and the shape memory alloy joint is fastened and contracted to be fastened, the member to be fastened and the joint. Since it can be heated while temporarily fixed to the proper position, fastening can be realized in a state where the positional relationship between the member and the joint is always normal, so that the performance of the joint is stable and the construction worker can Since it is not necessary to concentrate excessive attention on the positional relationship of the joint, the mental burden can be reduced, and the normal fastening work can be performed extremely efficiently.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of a device for explaining basic elements of the present invention.

FIG. 2 is a diagram showing standard steps of the method of the present invention.

FIG. 3 is a diagram illustrating a method when a part of the standard process of FIG. 2 is changed.

FIG. 4 is a diagram illustrating a method when a part of the standard process of FIG. 2 is modified.

FIG. 5 is a diagram showing an embodiment of the present invention.

FIG. 6 is a diagram showing an embodiment of the present invention.

[Explanation of symbols]

P1, P2 Members to be fastened such as pipes or rods J Shape memory alloy joint 100 Clamping mechanism 200 Heating mechanism 1 First clamper 12a First clamper one side clamping section 12b Other side clamping section 2 of the first clamper 2 Second clamper 22a 2nd clamper one side holding part 22b Other side holding part 13 of the 2nd clamper 23, holding force adjusting knob 14, 24 member receiving notch 16, 26 heating mechanism locking groove 3 connecting member 4 third clamper 41, 42 3rd clamper 5 of another form 5 Joint positioning notch 0 Marking 0'indicating the position of the tip of the member to be fastened Protrusion 6a for positioning the tip of the member to be fastened 6a 1st heating part 6b 2nd heating part 7 U-shape Frame 71a, 71b opposite sides 71c of the frame 71c first and second heating section connecting sides 8 handle 81 insertion limit stoppers 8a, 8b of heating mechanism heating section The handle 9 temperature measuring device S temperature-measuring detector at which a clamping type

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Toshiharu Kikuchi             1618 Ida, Nakahara-ku, Kawasaki-shi, Kanagawa             Inside the 1st Technical Research Laboratories (72) Inventor Takahiko Mio             3-6 Kandanishikicho, Chiyoda-ku, Tokyo Awaji Sangyo             Tokyo branch office (72) Inventor Kazutomi Oka             386-5 Kataoka, Hiratsuka City, Kanagawa Prefecture (72) Inventor Morihiko Yano             798-2 Shinomiya, Hiratsuka City, Kanagawa Prefecture

Claims (7)

[Claims] 1. A shape memory alloy joint made to allow two members such as a pipe and a bar to have an inner diameter smaller than an outer diameter of the two members and then to be expanded so that the member can be inserted. When fastening by using the first clamper and the second clamper, which are separated by a predetermined distance, temporarily fix each of the two members, and specify the relative positional relationship with respect to the temporarily fixed two members to temporarily fix the joint. After the joint is temporarily fixed by the third clamper for fixing, a heating device is housed between the first clamper and the second clamper, and the joint is heated to shrink the inner diameter of the joint, and the heating device is housed between the first clamper and the second clamper. A fastening method comprising fastening members. 2. The fastening method according to claim 1, wherein the heating mechanism is provided with a heating coil in a two-divided state, and the joint is induction-heated from the opposing radial direction. 3. A device for fastening a shape memory alloy joint for connecting two members such as a pipe and a rod, wherein each of the two members such as the pipe and the rod and the joint are positioned and temporarily fixed. The clamp mechanism includes a clamp mechanism and a heating mechanism for heating the joint, and the clamp mechanism includes a first clamper for temporarily fixing a member on one side to be fastened and a second clamper for temporarily fixing a member on the other side to be fastened. The first clamper and the second clamper are formed of a connecting material that holds the second clamper with a predetermined space therebetween, and a joint has a notch at a portion corresponding to an appropriate position and has two states of a standby position and a joint fixing position. A fastening device comprising a movable third clamper, wherein the heating mechanism is detachably accommodated between the first and second clampers of the clamp mechanism. 4. A frame in which a heating mechanism fixes a flat plate-shaped first heating part and a second heating part, in which a spirally wound conductor is embedded in a heat-resistant and non-conductive material, and both heating parts. The fastening device according to claim 3, wherein the fastening device is configured by a body and a handle connected to the body, and the magnetic fluxes generated from the conductors of the first and second heating units are connected to strengthen each other. 5. The joint by providing at least one of the first clamper and the second clamper with a stopper for abutting the end face of the joint at a proper position when the joint is inserted into the pipe or rod to be fastened. The fastening device according to claim 3, further having a function as a third clamper for positioning and temporarily fixing the. 6. A structure in which grooves are provided on the inner surface sides of the first clamper and the second clamper which face each other, and the frame bodies constituting the first and second heating portions of the heating mechanism are inserted along the grooves. The fastening device according to 3. 7. The first heating part and the second heating part of the heating mechanism are configured to be openable and closable with a base point on the handle side as a fulcrum, and the heating mechanism is attached to the clamp mechanism after temporarily fixing a pipe or a rod. The fastening device according to claim 3, wherein, when assembled, the first and second heating units are assembled in an open state and then closed to temporarily fix the joint.