JP2589447B2 - Elbow jig for friction welding machine and elbow jig with pipe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an elbow jig mounted on a fixed gripping device of a friction welding machine, and more particularly, to a friction welding operation in which one of friction-welded objects is an elbow, for example, an elbow. The present invention relates to an elbow jig capable of holding an elbow in a predetermined state and firmly so that friction welding with a pipe can be performed accurately and completely. Also, the present invention
Similarly, the present invention relates to a pipe-equipped elbow jig capable of firmly holding a pipe-equipped elbow in a predetermined state. In this specification, an elbow with a pipe refers to one in which a pipe is connected to one end of the elbow.

[0002]

2. Description of the Related Art A friction welding machine is a device for joining a tubular workpiece to a peripheral joint. One of a pair of workpieces to be pressed (a workpiece A) is fixed, and the other (a workpiece B). ) Is a device that is brought into contact with the workpiece A under pressure while rotating to perform pressure contact. There are various types of friction welding machines. As an example, a friction welding machine for a long pipe is shown in FIGS. The illustrated friction welding machine 50 includes a base 52, a fixed-side gripping device 56 fixed on the base 52 to grip the workpiece A,
And an operating body 58 that moves on the base 52 with respect to the gripping device 56. Further, the rotating body 70 is provided on the operating body 58.
A main shaft 100 extending through the operating body 58, integrally moving forward and backward, and being rotated by a rotating device 70 about a moving direction of the operating body, and an external burr cutting rotating with the main shaft. A device 78 is provided. The spindle accommodates the workpiece B inside thereof, and has the spindle gripping device 72 at the spindle end on the gripping device 56 side to grip the workpiece B.

Conventionally, a combination of workpieces that can be friction-welded in a friction welding machine with an external burr cutting device that has been put into practical use is as follows.
The combination of a pipe and a short pipe, or a combination of a pipe and a short pipe material such as a flange, a different diameter joint, a branch pipe, and the like, and a combination of an elbow and a pipe or an elbow with a pipe and a pipe, Since a suitable jig for holding the elbow has not been developed, friction welding cannot be performed.

[0004]

SUMMARY OF THE INVENTION A chemical device,
Process devices such as petroleum refining devices are formed by connecting a number of devices with piping. Such piping is 1
It is necessary to expand not only in two dimensions but also in two and three dimensions, and to branch in various ways, bend in some places, and have a connection end with equipment. In plumbing work, an elbow and a pipe or a pipe It is necessary to connect the attached elbow and the pipe. However, as described above, a suitable jig capable of gripping an elbow or an elbow with a pipe accurately and firmly to the extent that it can be friction-welded with a fixed-side gripping device has not been developed. However, a friction welding machine cannot be used for piping work requiring friction welding including an elbow as described above, and the use of the friction welding machine has been extremely limited.

Accordingly, a first object of the present invention is to provide an elbow for a friction welding machine which is capable of firmly gripping an elbow in a fixed state in a fixed side gripping device when performing friction welding using a friction welding machine. A second object of the present invention is to provide a jig, and an elbow jig with a pipe for a friction welding machine, which can firmly hold the elbow with a pipe in a predetermined state.

[0006]

The present inventor studied the conditions required for an elbow jig using an actual friction welding machine. As a result, firstly, the positioning and centering of the elbow were accurately performed. Secondly, the elbow can be held firmly against the thrust during friction welding, and thirdly, the elbow jig receives a large thrust and is easily worn away during welding, so measures against wear are taken. Is an important condition. Based on such knowledge, in order to achieve the above object, an elbow jig according to the present invention is a jig mounted on a fixed-side gripping device of a friction welding machine in order to firmly hold an elbow to be frictionally welded. , it is formed in the same contour as the outer shape of the elbow to be held, and only elbow length of at least the approach margin in the friction welding machine end protrude substantially with the end face of the elbow at the end <br/> surface of the other end D formed to be flush
Comprising a Rubo hollow portion, the said friction welding machine end of the elbow-shaped hollow portion connecter of high hardness, formed stopper as said the other end portion abuts against the end face of the elbow, mounted respectively is, the wall surface of the elbow-shaped hollow portion or intermittently a plurality of high hardness liner layer is annularly continuous in the circumferential direction of the elbow-shaped hollow portion or one another are spaced apart in the long side direction, further On the surface of the liner layer, a narrow groove is formed annularly in the circumferential direction of the elbow-shaped hollow portion, and the jig is fixed to the fixed side gripping device.
When mounted on the jig, the end face of the other end is horizontally
2 of a pair formed so as to be positioned and symmetrically divided with respect to a plane including a longitudinal center line of the elbow-shaped hollow portion.
It is characterized by being composed of a set of half halves.

[0007] Here, the approaching margin means a length shortened due to the generation of burrs. That is, in the process of friction welding of the workpiece, the portion softened by the frictional heat is joined while being discharged to the inner and outer surfaces of the tube by the thrust of the welding, so that the original base material portion becomes burr and rises to the inner and outer surfaces of the tube. As a result, the workpiece becomes shorter. This shortened length is called the shift. The half-split type material is not particularly limited as long as it has a strength capable of firmly holding the elbow, but is generally made of steel. The base provided at the end of the friction welding machine is preferably made to be replaceable because the elbow is more or less microscopically elastically deformed due to the thrust, and is likely to be worn away by receiving a large load. Hard materials that can be used for the base include, for example, hardened hardened steel.
Also, the liner layer is subject to similar loads and is easily worn away,
The material used is, for example, hardened hardened steel, similar to the base. The shape of the stopper is not particularly limited, as long as the stopper has a stopper surface formed so as to contact the end surface of the elbow.
It may be plate-shaped or ring-shaped.

The elbow jig with a pipe according to the present invention holds the elbow with a pipe by combining an elbow jig body having the above-mentioned elbow jig with the stopper removed and a standpipe. In the union jig, the stand pipe is in the elbow shape of the elbow jig body.
It comprises a tubular stand pipe main body having an inner diameter substantially the same as the inner diameter of the hollow portion, and a stand slidably hooked on the end face of the other end of the elbow jig main body. A cylindrical hollow portion having the same inner diameter as the outer diameter and being formed so as to be orthogonal to the end face of the other end of the elbow jig main body; and the cylindrical hollow portion having the same inner diameter as the inner diameter of the stand pipe main body. A shoulder portion projecting radially inward from the wall surface of the hollow portion in an annular shape so that the stand pipe body is fitted into the cylindrical hollow portion and supported by the shoulder portion, and the stand pipe has a longitudinal center line. consists of two half sets of pairs divided into symmetrically about the plane containing the pipe section of the pipe with an elbow in the standpipe, the elbow portion elbow jig body, characterized in that so as to accommodate each And

As in the embodiment described later, it is desirable to provide a cramp means such as a band for clamping the stand pipe on the upper portion in order to ensure the integrity of the stand pipe. Further, each of the stand pipe main body and the stand, which constitute the half of the stand pipe, may be integrally formed.

[0010]

According to the first aspect of the present invention, when the elbow jig is mounted on the fixed-side gripping device of the friction welding machine, the other end surface of the elbow jig is configured to be horizontal. When one end face of the elbow is aligned with the other end face of the elbow jig, the other face of the elbow is automatically vertically positioned as predetermined. Also, since the high-hardness liner layer with the fine grooves is engraved in the hollow part of the elbow jig,
When the elbow receives the thrust, the liner layer constituting the convex portion elastically contacts the elbow to reliably prevent the movement, and further, microscopically, the narrow groove of the liner layer elastically cuts into the surface of the elbow. To stop the movement completely. At the time of friction welding, when thrust acts on the elbow, the elbow is slightly elastically deformed microscopically, and a large load is generated at the end of the elbow jig hollow portion on the side of the friction welding machine, so that the end portion is easily worn out. However, since the high-hardness base is provided, no wear occurs and even if worn, the base may be replaced. In addition, since the elbow has at least a length longer than the margin, protruding from the base, there is no problem in friction welding.

According to the second aspect of the present invention, since the stand pipe stands upright in the direction perpendicular to the other end face of the elbow jig via the stand, the main body of the elbow jig is fixed at a predetermined position by the friction welding machine. When the pipe part of the elbow with a pipe is mounted on the standpipe, the end face of the elbow part is automatically and vertically positioned as specified.

[0012]

EXAMPLE Figure 1 elbow jig front embodiment of the elbow jig according to the present invention which holds the elbow view, FIG. 2 arrow left mold halves constituting the elbow jig of Figure 1 FIG. 3 is a side view of II, and FIG.
FIG. 4A is a cross-sectional view taken along the line III-III of FIG. 2 in order to show details of the liner layer provided on the wall surface of the hollow portion of the elbow jig. As shown in FIG.
The elbow jig 10 is a pair of left and right half halves 12A, 12A.
B. In FIG. 1, reference numerals 14A and 14B denote bases attached to the end of the elbow jig 10 on the friction welding machine side, respectively.
6A and 6B are stopper rings, and A and B make a pair, respectively. E is a retained elbow.

Since the left half mold 12A and the right half mold 12B of FIG. 1 have a symmetrical structure, the left half mold 12A will be described below. As shown in FIG.
The half mold 12A is made of a rectangular member 18 made of steel.
As shown in FIG. 3, a semi-circular groove 22 having a semi-circular groove side wall surface 20 is provided on the surface of the member 18 where the half mold 12A is in contact with the half mold 12B. Semi-circular shape of half type 12A
The groove 22 and the semicircular groove 22 of the half mold 12B are combined.
As described later, an elbow-shaped hollow portion 25 is formed.
You. As shown in FIGS. 3 and 4A, a plurality of relatively thin strip-shaped liner layers 24 are provided on the wall surface 20 so as to be spaced apart from each other in a direction perpendicular to the longitudinal center line of the groove 22. A plurality of narrow grooves 26 having a rectangular or triangular cross section are formed on the upper surface of the liner layer 24 in the longitudinal direction of the liner layer 24 , that is, around the hollow portion 25.
Engraved in the direction . The liner layer 24 is a hardened and quenched steel strip formed in a semi-annular shape, and is attached to the member 18 by an embedded bolt or the like (not shown). In this embodiment, the lengthwise side 27 of the liner layer 24 is directed toward the center of curvature of the elbow, and the width of the liner layer 24 is reduced from the periphery having a large radius of curvature to the periphery having a small radius of curvature. However, the present invention is not limited to this.

A plurality of liner layers 2 mounted in grooves 22
4 is a continuous envelope of the upper surface
The groove 22 and the liner layer 24 are formed so as to define the same outline as the left side portion of the external outline of FIG. Therefore, half type 1
When 2A and 12B are combined, the hollow portion 25 (see FIG. 1) formed by the groove 22 in the elbow jig 10
When the upper surfaces of the liner layers 24 are connected, the shape becomes equal to the outer shape of the elbow E.

[0015] cap 14A is a half of the same curing hardening steel ring to the outer diameter of the inner diameter D ₁ is elbow E, detachably to the friction welding machine end 28 of the member 18, for example studs ( (Not shown). on the other hand,
End face 30 of end 29 opposite to end 28 on the friction welding machine side
The stopper ring 16 is detachably attached thereto, and is attached to the stopper ring 16 by conventional means such as a combination of an annular groove and a key so that the stopper ring 16 does not come up against the upward force in FIG. Stopper rings 16 are in close contact with the end face 30 at its lower surface 32, and an inner diameter D ₂ is smaller than the inner diameter of the elbow E. Elbow E half-split type 1
The half mold 12A is configured so that one end face of the elbow E abuts on the lower surface 32 of the stopper ring 16 and the other end face protrudes from the base 14A by at least a length L longer than the offset margin when housed in the 2A. Have been.

Hereinafter, a method of using the elbow jig 10 will be described. The elbow jig 10 is used by being attached to a fixed-side holding device of a friction welding machine. There are various types of friction welding machines. Here, the friction welding machine 50 for a long pipe shown in FIGS. 7 and 8 will be described as an example. 7 is a plan view of the friction welding machine 50, and FIG. 8 is a side view of the friction welding machine 50. As shown in FIGS. 7 and 8, the friction welding machine 50 includes a base 52, a fixed-side holding device 56 fixed on a front end 54 of the base 52, and a fixed-side holding device 56 on the base 52. , A driving device 62 which is located on the rear end portion 60 side, is connected to the operating member 58 and can integrally move forward and backward, and an operating member 58 and a second driving device. 62 and another gripping device 64 connected to the operating body 58 and integrally advanced and retracted.

The base 52 is a rigid structure having a rectangular plane and a rear end portion 60 formed to be one step higher, and is fixed on the floor of a factory. The fixed-side gripping device 56 includes a pair of clamp claws 68A, B each having a driving device 66A, B, such as a hydraulic cylinder, on each of the left and right sides, and drives the clamp claws 68A, B by the driving devices 56A, B. Then, the workpiece or the jig 10 is clamped. Actuator 58
Is a main body 100 that is a rectangular-shaped rigid structure and is mounted in the operating body 58 to house and grip a workpiece such as a pipe.
As drive device for rotating the electric motor 70 includes on its upper surface and the spindle gripping device 72 on the front, slides on the base 52 in the longitudinal direction of the base 52 at the bottom, stationary gripping device 56 Move forward and backward. Forward and backward movement of the actuating member 58 is a base 52 integrally formed with the support member 74A erected on the left and right, fixed drive device 76A to B, B,
For example, it is performed by the driving force of a hydraulic cylinder.

In the illustrated example, one of a pair of tubular workpieces to be pressed is an elbow E, which is clamped by a fixed-side gripping device 56 via an elbow jig 10 according to the present invention. The other workpiece B is a long pipe, which penetrates the operating body 58 and one end of which is clamped by the gripping device 64 .

In order to mount the elbow jig 10 on the friction welding machine 50, first, the elbow jig 10 is held at a predetermined position by a gripping device 56.
Is placed so that the end face 30 is horizontal. Next, the elbow E is housed in the elbow jig 10 in a predetermined manner such that one end surface of the elbow E is brought into contact with the stopper ring 16. Subsequently, the drive devices 66A and B are operated while the other workpiece B is being aligned, and the clamp claws 68A and
B tightens the elbow jig 10, thereby holding the elbow E firmly in a predetermined state.

As described above, the elbow jig 10 is
, When the elbow E is gripped, one end face of the elbow E is kept horizontal, the other end face is automatically aligned with the other workpiece B, and is perpendicular to the main shaft of the friction welding machine. Is positioned at a right angle. When the elbow E comes into contact with the workpiece B and is pressed against the workpiece, the elbow E receives a large thrust. However, the liner layer 24 forming the convex portion elastically abuts the elbow E to reliably prevent the movement due to the thrust. Further, microscopically, the narrow grooves 26 of the liner layer 24 elastically bite into the surface of the elbow E to completely stop the movement, so that the pressure welding can be reliably performed without changing the position. In addition, since the elbow E protrudes from the base 14 by at least the length of the offset margin, there is no problem when friction welding is performed and when the external burr is cut by the external burr cutting device 78 after the pressure welding.

Embodiment of an Elbow Jig with a Pipe FIG. 5 is a front view of an embodiment of an elbow jig with a pipe according to the present invention holding an elbow with a pipe composed of an elbow E and a pipe P, and FIG. It is a side view from the arrow IV-IV of the left part which comprises the elbow jig with a pipe. The elbow jig 80 with a pipe is composed of two halves obtained by removing the stopper ring 16 from the elbow jig 10 of the above embodiment.
That elbow jig body 81 A, 81B and the stand pipe 82
The standpipe 82 is composed of a standpipe main body 84 and a stand 86. Both the stand pipe body 84 and the stand 86 are paired with the left and right stand pipe halves 84A and 84B and the stand half 86 in the same manner as the elbow jig bodies 81A and 81B.
A, 86B. In FIG. 5 , reference numeral 88 denotes a band-like band wound around the upper portion of the stand pipe half 84 to integrally tighten the stand pipe halves 84A and 84B. Reference numeral 92 denotes an adjustment bolt for adjusting the verticality of the pipe P accommodated in the stand pipe 82, as will be described later.

The left part (part A) and the right part (part B) of the stand pipe 82 shown in FIG.
The left side of the stand pipe 82 will be described below. In addition, the elbow jig main body 81 is formed by moving the stopper ring 16 from the elbow jig 10.
Are omitted from the description.
As shown in FIG. 6, the left part of the stand pipe 82
It is composed of a stand pipe half 84A and a stand half 86A. Standpipe halves 84A, the inner diameter D ₃ is formed of a semi-cylindrical member is equal to the outer diameter of the pipe P connected to the elbow E (generally a short pipe), the length of which elbow E Is determined according to the length of the pipe P connected to the pipe P, but does not necessarily require the same length as the pipe P.

The lower portion of the stand pipe half 84A is fitted into the stand half 86A. Stand half 86A
Is a member mounted on the end surface 30 of the half mold 12A, and is one of members that constitute a pair of thick-walled cylinders having a hollow portion having a circular cross section in a direction perpendicular to the end surface 30. Hollow upper portion of the stand 86 has the same diameter as the outer diameter D ₄ of the stand pipe halves 84A, the intermediate portion consists of a shoulder portion 94 which projects annularly inwardly, the shoulder 94 is fitted to the standpipe and a half The body 84A is supported. Shoulder 94
The inner diameter D _5, the inside diameter D ₃ of the stand pipe halves 84A,
That is, it is the same as the outer diameter of the pipe P. The diameter of the lower portion of the hollow portion below the shoulder portion 94 is larger than the diameter of the upper portion of the shoulder portion 94 and the diameter of the hollow portion, and in this embodiment, for convenience, the stopper ring 16 which is a component of the elbow jig 10 can be just accommodated. Is formed.

The stand half 86A is connected to the half mold 12A by a shoulder bolt 96 so as to be slidable with respect to the end face 30 of the half mold 12A. The diameter and shaft of the head of the shoulder bolt 96 are provided on the stand half 86A.
T-shaped groove 98 having the same diameter as the diameter of the portion
But as a space to accommodate the head of the shoulder bolt 96
Provided , so that the stand half 86A has an end face
30 and can slide back and forth and right and left . Adjustment bolt 92
Is moved into and out of the stand pipe half 84,
A bolt capable of adjusting the perpendicularity of the pipe P accommodated in the standpipe half 84 to the horizontal plane, and when the standpipe halves 84A and B are combined to form the standpipe body 84, at least 90 ° So that they are provided at four separate locations.

The method of using the elbow jig 80 with a pipe is as follows.
The elbow jig 10 is substantially the same as the elbow jig 10, and the elbow E is connected to the stand pipe 84 and the elbow E is connected to the elbow jig body 81 on the gripping device 56 of the friction welding machine 50.
And the band 90 is fastened. After that,
The operation is performed in the same manner as in the case of the elbow jig 10.

According to the present embodiment having the above-described configuration, when the pipe portion P of the elbow with a pipe is accommodated in the stand pipe 84, the elbow E is automatically held vertically and the end face of the elbow E on the friction pressure contact side is automatically adjusted. It is positioned perpendicular to the main axis of the friction welding machine in alignment with the other workpiece B. Even if there is a slight misalignment between the elbow E and the pipe P, the stand 86 is connected to the elbow jig main body.
The elbow with a pipe can be accommodated by sliding in contact with the end face 30 of 81, and adjustment can be made by moving the adjustment bolt 92 forward and backward even if the perpendicularity between the elbow E and the pipe P is somewhat poor. Can be. The effects relating to the elbow E are the same as in the embodiment described above.

[Modification 1] In both of the above-described embodiments, the liner layer 24 has been described as being formed in a continuous annular shape. But it is good. [Modification 2] In both of the above-described embodiments, the narrow groove 26 provided in the liner layer 24 is formed.
Groove cross-sectional shape has been described in the rectangle, also exhibits the same effect with triangles as shown in Figure 4 (b). [Modification 3] In the embodiment of the elbow jig with a pipe , the stand pipe 8 is used.
Although 2 has been described as a pair, it is possible to use only the portion A. In this case, the operator of the friction welding machine can visually check the mounted state of the elbow with the pipe. [Modification 4] In the embodiment of the elbow jig with the pipe, the stopper ring is used.
16 is not attached, but the lower cavity of the stand 86
Can also be set to This allows the
The rubo jig 80 can also be used as an elbow jig [Modification 5] In the embodiment of the elbow jig with a pipe, each half or half A of the stand pipe body 84 and the stand 86 is a separate part. However, it may be formed as an integrated type of a cast product or a forged product.

[0028]

According to the first aspect of the present invention, the elbow can be positioned at the correct position and in the correct direction on the fixed-side gripping device and firmly held during friction welding.
This makes it possible to perform friction welding of a member including an elbow, for example, friction welding of an elbow and a pipe, which was conventionally difficult in practice. According to the second aspect of the present invention, the elbow with a pipe can be positioned in the correct position and the correct direction in the fixed-side gripping device and firmly held in the friction welding operation. This makes it possible to perform friction welding of an elbow with a pipe, which was conventionally difficult in practice.

[Brief description of the drawings]

FIG. 1 is a front view of an embodiment of an elbow jig according to the present invention.

FIG. 2 is a half view arrow I- constituting the elbow jig of FIG. 1;
It is a side view of I.

FIG. 3 is a cross-sectional view taken along a line II-II of a wall surface of a hollow portion of the elbow jig of FIG. 2;

4 (a) and 4 (b) are views II in FIG. 2, respectively.
It is sectional drawing of I-III.

FIG. 5 is a front view of an embodiment of an elbow jig with a pipe.

6 is a side view of the left side part of the elbow jig with a pipe shown in FIG. 5, taken along the line IV-IV.

FIG. 7 is a plan view of a friction welding machine.

FIG. 8 is a side view of a friction welding machine.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Elbow jig 12 Half mold 14 Base 16 Stopper ring 18 Member 20 Wall surface 22 Groove 24 Liner layer 25 Hollow part 26 Narrow groove 28 Friction welding machine side end 29 End opposite to friction welding machine side end 30 End face 32 Lower face 80 Elbow jig with pipe 81 Remove the stopper ring from the elbow jig of the first embodiment.
Ri eliminated therefrom 82 standpipe 84 standpipe body 86 stands 88 band 90 volts 92 adjustment bolt 94 shoulder 96 shoulder bolt

Claims (3)

(57) [Claims] A fixed gripping device (5 ) of a friction welding machine (50) for firmly holding an elbow (E) to be frictionally welded.
A jig (10) to be attached to 6) , wherein the jig is formed to have the same contour as the outer shape of the elbow to be held, and the elbow protrudes at least at a length of a margin at a friction welding machine side end (28). The elbow formed so that the end surface (30) of the end portion (29) is substantially flush with the end surface of the elbow.
A high-hardness base (14) is formed at the end of the elbow-shaped hollow portion on the side of the friction welding machine, and the other end is formed so as to contact the end surface of the elbow. stopper (16), respectively mounted, a plurality of high hardness liner layer on the wall surface (20) of the elbow-shaped hollow portion (24) and continuously in an annular or intermittently in the circumferential direction of the elbow-shaped hollow portion, or One long-side direction mutually are spaced apart to further narrow groove on the surface of the liner layer (26) is d
Are engraved annularly circumferential direction of Rubo hollow portion, when wearing the jig to the stationary gripping device, jig end surface of the other end portion is formed so as to be positioned horizontally cage, and the two mold halves of pairs divided into symmetrically about a plane containing the longitudinal center line of the elbow-shaped hollow portion pairs (12A,
12B) an elbow jig for a friction welding machine. 2. The elbow jig (1 ) according to claim 1,
A combination jig (80) configured to hold an elbow with a pipe by combining an elbow jig body (81A, 81B) having a configuration in which the stopper (16) is removed from 0) and a standpipe (82). The standpipe is the elbow-shaped hollow part of the elbow jig body.
A tubular stand pipe body (84) having an inside diameter substantially the same as the inside diameter of (25) , and a stand (86) slidably hooked on the end face of the other end of the elbow jig body. The stand has a cylindrical hollow portion having the same inner diameter as the outer diameter of the stand pipe main body and formed so as to be perpendicular to the end face of the other end of the elbow jig main body, and the stand pipe main body. A shoulder (94) projecting radially inward from the wall surface of the cylindrical hollow portion so as to have the same inner diameter as that of the cylindrical hollow portion. The standpipe has a pair of two halves (82A, 82A) that are symmetrically divided with respect to a plane including the longitudinal center line thereof.
B), wherein the pipe part of the elbow with a pipe is accommodated in a stand pipe, and the elbow part is accommodated in a main body of the elbow jig , respectively. 3. Half (8 ) of said stand pipe (82)
2A) constituting the semi-% of the stand pipe body (84)
The elbow jig with a pipe for a friction welding machine according to claim 2, wherein the (82A) and the half (86A) of the stand (86) are formed integrally.