JPS5858985A - Friction pressure welding machine - Google Patents

Abstract

PURPOSE:To prevent deformation, damage etc. of a work piece and clamp claw and to make the size of the clamping mechanism and frame small by providing an auxiliary centering clamping mechanism near the pressed part of a non-rotating work piece and two floating clampings mechanism in the rear of it. CONSTITUTION:A non-rotating work piece W' is supported sorresponding to the center axis line O of a spindle 4, and clamped relatively weakly by clamp claws 19, 20 of an auxiliary centering clamping mechanism C, and at the same time, clamped relatively strongly by claws 53, 54 of a main centering clamping mechanism D. Then, the piece W' is held relatively weakly by claws 68, 74 of a floating clamping mechanisms E1, E2. Next, relatively weak holding or clamping is released, and a pair of claws 74, 68 are brought into close contact with the claw 53 using a thrusting lever 76 of a clamp claw contacting mechanism, and clamped relatively strongly by them. A rotating work piece W hold by a chuck 5 is moved to the right, and tip faces of pieces W, W' are pressed against each other and the two work pieces are joined by frictional heat.

Description

[Detailed Description of the Invention] The present invention uses relative rotation and contact pressure under axial thrust to generate frictional heat in the contact area of a pair of workpieces to cause plastic deformation, and to join the workpieces by abruptly stopping rotation. The invention relates to a friction welding machine.

Conventionally, friction welding machines consist of a clamping rotating machine consisting of a spindle box, chuck, etc. that clamps and rotates one workpiece, and a clamping rotary machine that forcibly clamps and holds the other workpiece in a fixed position without rotating. It is composed of a centering clamp mechanism with an alignment function and a thrust receiving mechanism that corresponds to the rear end of the workpiece and receives thrust in the direction of the contact pressure that acts on the workpiece during contact pressure. Since one centering clamp mechanism is used to hold the work piece on the stationary side, the thrust receiving mechanism due to the frictional force between the work piece and the clamp claw is also made much thicker. Therefore, there was a drawback that the entire device became larger.

In particular, if the work piece is distorted, the degree of adhesion between the work piece and the centering clamp claw will deteriorate and the frictional force between the two will be reduced, resulting in a reduction in the thrust receiving capacity and even if the same clamping force is applied, the work piece will not be clamped. Since the pawl and the work piece tend to slip, it was necessary to increase the size of the thrust receiving mechanism.

Furthermore, in order to eliminate the above-mentioned defects, conventional friction welding machines were equipped with two centering clamp mechanisms, but deformation and damage to workpieces or clamp claws can be reduced to a certain degree, and the clamp mechanism and frame can also be made smaller to some extent. However, it is still impossible to omit the thrust receiving mechanism corresponding to the rear end of the work piece, and it cannot be said to be a sufficient solution.

In addition, by installing three or more centering clamp mechanisms in parallel, it is possible to improve the '-thrust receiving capacity, omit the thrust receiving mechanism corresponding to the work piece, and downsize each clamp mechanism and frame. However, it would be extremely difficult to install three or more centering clamp mechanisms at the same location in terms of manufacturing and assembly, and it would be difficult to place a distorted workpiece in three or more locations. If you try to clamp it tightly, a problem arises in that a large force is forced to act on the work piece.

The object of the present invention is to provide an auxiliary centering clamp mechanism close to the pressure contact part of a non-rotating work piece, and to provide an auxiliary centering clamp mechanism that is easy to manufacture, assemble, or work even if a plurality of auxiliary centering clamp mechanisms are installed in parallel behind the auxiliary centering clamp mechanism. By installing one or more floating clamp mechanisms that do not cause problems, it is possible to prevent deformation and damage to the work piece and clamp claws, and the clamp mechanism and frame can be made smaller. It is an object of the present invention to provide a friction welding machine which can improve thrust receiving capacity and make the entire device compact by omitting a thrust receiving mechanism corresponding to the rear end of a work piece.

An embodiment of the friction welding machine of the present invention will be described below with reference to the drawings.

The friction welding machine of this embodiment, as shown in FIGS. 1 and 2, grips and rotates the first work piece W while moving it in the direction of contacting the second work piece W. The rotary contact pressure mechanism A of the 1st. A thrust receiving mechanism B capable of receiving the thrust acting on the second workpieces w and w', and a grasping force for clamping the tip of the second workpiece W' and holding it in a predetermined position. A comparatively weak auxiliary centering clamp mechanism C and a fixed stopper bracket 6 located behind the clamp mechanism C and constituting the thrust receiving mechanism B are used to clamp the intermediate portion of the second workpiece W'. A main centering clamp mechanism with relatively strong gripping force for gripping and holding in a predetermined position, and a main centering clamp mechanism disposed close to the clamp mechanism,
Two first and second floating clamp mechanisms El and E2 with relatively strong gripping force are configured to clamp and grip the middle part of the second work piece W' along its outer circumferential surface, and a further clamp mechanism. The lamp claw contact mechanism F is configured to bring the clamp claws 68, 74 of the first and second floating clamp mechanisms El and E2 into close contact with the clamp claws 53 (54).

Therefore, among the above-mentioned mechanisms, the rotary contact mechanism A and the thrust receiving mechanism B of the first workpiece W will be explained with reference to FIG. A spindle box 3 is supported on the table 2 so as to be slidable back and forth in the left-right direction in FIG. 1, that is, in the direction of contact with the first workpiece W. The spindle box 3 supports a spindle 4 in the pressure direction, which is rotated at high speed by a motor (not shown) and suddenly stopped by a stop mechanism. A chuck 5 for gripping the first workpiece W is attached to the tip of the spindle 4.

A fixed stopper bracket 6 constituting the thrust receiving mechanism B is erected and fixed on the upper right end of the frame 1, and a movable stopper bracket 7 is mounted on a roller or flat surface (not shown) on the left side of the upper surface of the frame 1 so as to correspond to the bracket 6. It is supported so that it can reciprocate in the left and right direction by sliding contact.

The movable stopper bracket 7 and the fixed stopper bracket 6 are connected and fixed by a pair of hollow rods 8.9 that receive thrust. A thrust cylinder 10 is fixed to the rear surface of the movable stopper bracket 7, and its piston rod 11 passes through the bracket 7 and is connected to the spindle box 3 in the front.

In this embodiment, the spindle 4 and the piston rod 1
1, and the pair of tie rods 8 and 9 are disposed at positions equidistant from the central axis O and 180 degrees apart (see FIG. 3). Therefore, when the piston rod 11 of the thrust cylinder 10 is moved to the right in FIG.
, chuck 5, etc. are moved together in the same direction, and the tip of the first workpiece W is brought into pressure (material contact) with the tip surface of the second workpiece W'. When thrust is applied to the second workpieces w and w', the reaction force is applied to the chuck 5, spindle 4,
Box 3, piston rod 11, thrust cylinder 1
0 and the movable stopper bracket 7 to the pair of tie rods 8 and 9.

Next, the auxiliary centering clamp mechanism C clamps and holds the tip of the second work piece W' in a fixed position without rotating.
Referring to FIG. 3, a support 12 is fixed horizontally to the upper surface of the frame 1 so as to be perpendicular to the central axis 0 of the spindle 4, and a slide base 13 is fixed to the upper surface of the support 12. There is. Same slide base 13
Fixed brackets 1-14.15 are arranged on both sides of the upper surface, and a movable bracket 16.17 is supported in front of both brackets 14.15 so as to be able to reciprocate toward the central axis O. Front vertical surfaces 16a, 17a of the movable brackets) 16, 1.7, horizontal surfaces 161), 1
71), clamp claws 19 and 20 are secured by bolts 21 via shim plates 18, respectively.

Incidentally, arc-shaped pads 22 are fitted into the front surfaces of the clamp claws 19 and 20, respectively, and keys 23 are fitted into the lower surfaces of the clamp claws 19 and 20 for transmitting pressure to the movable brackets 16 and 17.

On the agreement bracket 14.1'4, equalizer levers 24.25 are rotatably supported by pins 26.27, and at the lower ends of both levers 24.25, an equalizer link 2B is supported in a parallel manner by pins 29.30. They are articulated to form clause links. Further, another equalizer lever 33,34 is connected to the front end of the equalizer lever 24, 2% by means of a pin 31,32.
．． The tip end of 34 is articulated to the movable bracket 16.17 by a pin 35.36.

On the other hand, a clamp cylinder 37 is fixed to the rear end surface of the fixed bracket 14, and a connecting link 40 is articulated by a pin 39 between the piston rod 3B of the cylinder and one end of the equalizer link 2B. There is. Therefore, when the clamp cylinder 37 is actuated and its piston rod 38 is moved to the left in FIG.
The equalizer link 28 is swung in the same direction via the levers 33, 34, 33, 34, and 34, so that the lever 24.25 is rotated clockwise in FIG. 3 about the pin 26.27.
The movable bracket 16.17 and the clamp claw 19.20 are each moved at a constant speed toward the center axis 0, and the tip of the second workpiece W' is in the fixed position, and then the main centering clamp mechanism is moved to the fourth position. To briefly explain the figures and FIG. 5, a support stand 41 is fixedly installed on the upper surface of the frame 1 in a horizontal direction perpendicular to the center axis 0 of the spindle 4, and on the upper left and right sides of the support stand 41 there are horizontal square posts. Fixed guide frames 42.43 are arranged, and clamp cylinders 44.45 are fixed to the rear ends of both guide frames 42.43 so as to face each other.

Movable brackets 46 and 47 are slidably supported within the guide frames 42 and 43 so as to be movable toward and away from the center axis 0 of the spindle 4. Said clamp cylinder 44.45
As shown in FIG. 5, on the distal end surface of the piston rod 48, there is a square plate-shaped plate that is loosely fitted into a recess 47B formed on the rear end surface of the movable bracket 46, 47 (only the 41 side is shown in FIG. 5). A connecting block 49 is secured by bolts 50. Key grooves are formed on both sides 1 of the connecting block 49 and on both sides of the recess 47B, and the key 5
1 is inserted loosely. Therefore, when the piston rods 4B of the clamp cylinders 44, 45 are reciprocated in the front-rear direction, the movable bracket 47 is moved through the end surface of the piston rod 48 during forward movement and through the connecting block 49 and key 51 during backward movement. is reciprocated in the direction.

The front vertical surface 461) of the movable bracket) 46.47)
, 471) and the horizontal surface 46 (: , 47 (l), clamp claws 53.54 are fixed by bolts 55 via shim plates 52. Furthermore, on the opposite surface of the clamp claws 53.54, a second An arc-shaped pad 56 is fitted to clamp the outer circumferential surface of the workpiece EW', and the movable bracket 46 is attached to the lower surface to transfer the thrust that acts on the second workpiece W' during contact pressure.
A key 57 is inserted therein to transmit the information to 47 degrees.

As shown in FIG. 5, a fixed pressure-receiving ring 5B that receives thrust during pressure-contacting work is fitted into recesses 5.4a formed on both sides of the clamp claw 54.

A movable pressure receiving ring 59 is engaged with a pressure receiving surface 58 having an arcuate cross section formed on the inner edge of the ring 58 so as to be slidable in any direction. Further, a pressure receiving metal fitting 60 is fitted into the movable pressure receiving ring 59, and is fastened to the clamp claw 54 with a bolt 61. A surface contact holding mechanism for bringing the clamp claw 54 into surface contact with the fixed stopper bracket 6 is formed.

On the other hand, a pressure receiving member 62 is fixed to the front surface of the fixed stopper bracket 6 so as to correspond to the pressure receiving metal fitting 61.
A certain minute gap 01 is formed between the pressure receiving member 62 and the pressure receiving metal fitting 60. The smaller this gap 01 is, the more desirable it is, and it is also possible to eliminate it and make the two contact each other.
In this case, the number is usually set to 0.1 to 0.3, since problems may occur in manufacturing and assembly, and parts may become more prone to wear.

As shown in FIG. 4, the movable brackets 46 and 47 have leg pieces 4f, d, and 47d on the lower front side, respectively.
A pair of equalizer links are provided between the lower ends of both leg pieces 46d and 47d and both ends of an equalizer mechanism 64 rotatably supported by a support shaft 63 in the center of the support base 41. 65 are connected by pins 66, respectively. Therefore, when the movable brackets 1-46, 47 are pushed by the piston rod 48 of the cylinder link 44, 45, both the brackets 46, 47 and the clamp claws 53, 54 are moved at the same speed by the lever 64 and the link 65. The second workpiece W' is clamped and held in a fixed position coincident with the central axis O by clamp claws 53,54.

Next, two first and second floating units are arranged to clamp the second workpiece W' which has been clamped in place by the auxiliary and main centering clamp mechanism C1D along the circumferential surfaces on both sides thereof. Among the clamp mechanisms El and E2, the first floating clamp mechanism El is equipped with a clamp claw contact mechanism F.
will be explained with reference to FIGS. 6 to 8.

As shown in FIG. 6, this clamp mechanism E1 has a movable bracket 46.
The equalizer mechanism that moves 7 at a constant speed is omitted, and the pair of left and right clamp claws 68 for 46.47
．． The difference is that the main centering clamp mechanism 68 is supported in a floating manner, and the other configurations are the same as the main centering clamp mechanism, so of the pair of different left and right floating mechanisms, the right clamp claw 68 will be described.

As shown in Figure 7, the front vertical surface 4 of the movable bracket 47
71) is formed with an arcuate pressure-receiving concave surface 41-() in the vertical direction tζ, and two claw support rods 67 are erected on the horizontal surface 47c as shown in FIG.

A clamp claw 68 is loosely fitted to the support rod 67 so as to be able to float in any direction. A support ring portion 681 is provided in the middle of the support rod through hole 68a on the 6th day of the clamp claw.
+ is integrally formed. A spring receiver 69 and a plurality of disc springs 70 are provided between the horizontal surface 4TC of the movable flaket 41 and the lower surface of the support ring portion 681 and between the ring portion 681) and the heads 67B of the support rods 6 and 7.
are interposed therebetween to elastically hold the clamp claw 68 in a state floating above the horizontal surface 47C. Note that a lid 71 is attached to the upper end of the through hole 68)l with screws.

The movable bracket 47 is provided on the rear surface of the clamp claw 68.
A pressure receiving block 72 having an arcuate pressure receiving convex surface 12+L that is in close contact with the arcuate pressure receiving concave surface 4-7e is fixed (it may be held in a sandwich-like manner simply by making contact with it). A stopper plate 13 for regulating the upward position of the pressure receiving block 12 is fixed to the upper part of the movable bracket 47 with bolts.

Therefore, the piston rod 48 of the lamp cylinder 45
is moved in the direction of the arrow in FIG. 6, the piston rod 48
The movable bracket 47 is pushed by the tip of the movable bracket 47.
are moved in the same direction, and the clamp claw 68 is moved and pressed against the outer surface of the second work piece W' held in a fixed position.

At this time, the clamp claw 68 and the movable bracket 47
Since it is floatingly supported, the bad 56
The entire workpiece is brought into close contact with the outer peripheral surface of the second workpiece W' which is clamped in place. Therefore, the second workpiece W
The thrust force acting on the second workpiece 1 may cause damage by strongly pressing the curved surface of the second workpiece W′, or may cause a bending reaction force on the clamp claw 68, or may cause a poor contact between the pad s6 and the workpiece W′. This prevents the retention function from deteriorating. In particular, the provision of a floating clamp mechanism is very effective for clamping workpieces such as seamless pipes for oil drilling, which have extremely poor coaxiality.

Another second floating clamp mechanism E2 interposed between the main centering clamp mechanism and the first floating clamp mechanism El is configured almost the same as the first floating clamp mechanism E1. Clamp claw 74.7 of floating clamp mechanism E2
4 and the clamp claws 53 and 54 as shown in FIG. 9(a).
As shown in , the minute gap 62 < o, t~Q, 3arg
) are provided for each. Moreover, the clamp claw 74
．． There is also a small gap Ga between 74 and the clamp claws 68 and 68.
(0,1-OJH) is provided.

Next, the first clamp claw 53 and 54 of the main centering clamp machine WIID mentioned above are used. Clamp claw 68.68.74.7 of second floating clamp mechanism E, , E2
The right-hand contact mechanism F of the pair of clamp claw contact mechanisms F that brings the clamps 4 into close contact will be described with reference to FIG.

A bracket support shaft 76 is provided on one side of the fixed guide frame 43.
For pressing the clamp claw, the central portion of the lever 77 is supported so as to be horizontally rotatable. Similarly, a relatively small-capacity cylinder 78 is fixed to one side of the guide frame 43, and the tip of a piston rod 79 of the cylinder 78 is connected to the rear end of the clamp claw pressing lever 77. In addition, for pressing the clamp claw, the tip of the lever 77 is bent at a right angle toward the clamp claw 68, and can come into contact with the end surface of the pressure receiving metal fitting 60, similar to the one described above, formed and arranged at the end of the same type 6B. It is said that

Therefore, the piston rod 79 of the cylinder 7B is the seventh
When the clamp claw is pushed in the direction of the arrow in the figure, the lever 7
7 is rotated in the clockwise direction in FIG. 7 around the support shaft 76,
The clamp claw 68 in the floating state is connected to the lever 77.
is pressed toward the clamp claw 74 (clamp claw 6
8 and the pressure receiving block 72 are integrated, the arcuate pressure receiving concave surface 47 (which can be moved by a set amount depending on the size of the gap between 1 and the arcuate pressure receiving convex surface 72a); The clamp claw 74 is in close contact with the clamp claw 54 of the main centering clamp mechanism I), and the three clamp claws 6
B, 74.54 are tightly pressed together like one rigid body.

Next, the operation of the friction welding machine configured as described above will be explained.

In FIG. 9(a), the second workpiece W' is supported by a support roller (not shown) at a fixed position corresponding to the center axis 0 of the spindle 4, and each clamp m structure c, D, El, E2
indicates an inactive state. In order to clamp the second work piece W' in this state, first, as shown in FIG. 9(I), the work piece W is
The tip of the workpiece W' is clamped with a relatively weak force (for example, 4°1, on), and the middle part of the workpiece W' is clamped with a relatively strong force (for example, 4°1, on) using the clamp claws 53 and 54 of the main centering clamp mechanism.
For example, 2001. on ) to hold it in place.

Subsequently, the clamp claws 68, 68 and 74 of the two first and second floating clamp mechanisms E+, E2.
74 applies a relatively weak force (
For example, 3 Q1. (on) (Fig. 9 (h)
reference). After that, while holding the work piece W' with a relatively weak force or with the clamping pressure released, the clamp claw contact mechanism F is pressed by the lever? Clamp claw 74.74.68.68 against clamp claw 53 (54) by ff (7B)
are brought into close contact with each other as shown in FIG. 2. Clamp the workpiece W' along its outer circumferential surface.

After the second workpiece W' is clamped and held in a predetermined position in this way, the thrust cylinder 1o is operated to move the first workpiece W, which is gripped and rotating by the chuck 5, to the right (c). by moving the tip of the first workpiece W onto the tip of the second workpiece W'' (for example, /40).
on or 150tOn), both workpieces w
, Frictional heat is generated on the contact pressure surface of w', causing plastic deformation, and after a certain period of time, the chuck 5 is suddenly stopped and left as it is, or at the same time as the sudden stop, or after a minute time, an even higher thrust than mentioned above is generated. After adding the first. 2nd workpiece w,
w' is combined.

By the way, during the contact pressure work shown in FIGS. A thrust force T (1
5Qt, on) acts, a reaction force of the same strength is applied to the two tie rods 8 and 9, and therefore the frame 1
The fixed stopper bracket 6 fixed to is about to be pulled leftward with a strong force as shown in FIG. 9(d). However, at the same time as the contact pressure work starts, a thrust force T also acts on the second work piece W', and this thrust force is applied to the parts 74.53 and 6 B, 74, 5
．． 4, each clamp pawl 6 substantially fixed to the frame 1 by clamping the second work piece W'.
B, 74° 53 and 6B, 74.54 are moved toward the fixed stopper bracket 6 together with the second workpiece W' by a clamping mechanism, and are brought into close contact with the fixed stopper bracket 6 while slightly elastically deforming El and E2. As a result, the fixed stopper bracket 6 and the clamp claws 53 and 54 come into close contact with each other with the same thrust force T, but because the gap Gl between the fixed stopper bracket 6 and the clamp claws 53 (54) is minute, the clamp mechanism Before El and 'E2 are elastically deformed and a large bending load is applied to the frame 1,
The fixed stopper bracket 6 and the clamp claw 53 (54) are in close contact and cancel each other's thrust, so that the fixed stopper ts
No bending load or tensile load is applied to the frame via the O-bracket 6 and the clamp mechanism Et, E2, and the thrust force T is received by the tie rods 8 and 9.

Now, in the embodiment of the present invention, an auxiliary centering clamp mechanism C is installed close to the pressure contact part of the second workpiece W', and two first and second clamp mechanisms are installed behind the clamp mechanism C. Floating clamp mechanism - E1 and E2 are installed, so the clamping force of the auxiliary centering clamp mechanism C, which is likely to cause deformation and damage to the workpiece and clamp claw, is weakened, and the floating clamp is less likely to cause deformation or damage. Mechanism El,
By increasing the clamping force of E2, deformation and damage to the work piece and clamp claw can be reduced.

In addition, in the embodiment of the present invention, the auxiliary centering clamp mechanism C
and two floating clamp mechanisms El.

Since E2 is installed, the force for clamping the second workpiece W' is reduced by 3.
By dividing the clamp mechanism into three parts, each of the clamp mechanisms C, El, and E2 can be made smaller, and the frame that supports the clamp mechanism can be made smaller.

Furthermore, since the embodiment of the present invention uses a floating clamp mechanism that does not require much precision in manufacturing and assembly,
The thrust receiving capacity can be increased by installing multiple floating clamp mechanisms in parallel, and the second workpiece W'
There is no need to provide a thrust receiving mechanism corresponding to the rear end of the device, and the entire device can be made more compact.

Furthermore, in the embodiment of the present invention, the second workpiece W' and the floating clamp claws 68, 74 are in good contact with each other, so even if the same clamping force is applied, the frictional force between the workpiece W' and the clamp claws is high. Therefore, the thrust receiving ability of the clamp claws 68, 74 is improved, and it becomes easier to omit the thrust receiving mechanism corresponding to the rear end of the second workpiece W'.

Note that the present invention can also be embodied in the following embodiments.

(1) Instead of the main centering clamp mechanism of the above embodiment,
Use a floating clamp mechanism. In addition, one or three or more flow element ink clamp mechanisms must be installed.

(2) The stopper bracket 7 can be fixed, the fixed stopper racket 6, the tie rods 8 and 9, and the clamp claw contact mechanism F are omitted, and the thrust force is received by the frame 1 through each clamp mechanism.

As detailed above, the present invention can prevent deformation and damage to workpieces and clamp claws, downsize the clamp mechanism and frame, improve thrust receiving ability, and improve machining. There is an effect that the entire device can be made more compact by omitting the thrust receiving mechanism corresponding to the rear end of the piece.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an embodiment of the friction welding machine of the present invention, FIG. 2 is a plan view of FIG. 1, and FIG. 4 is an enlarged sectional view taken along the Y=Y line in FIG. 1, FIG. 5 is an enlarged sectional view taken along the ZZ line in FIG. 6 is an enlarged sectional view taken along line I-/r in FIG. 6, FIG. 8 is an enlarged sectional view taken along line J- and 1 in FIG. It is a diagram. Auxiliary centering clamp narrow groove 01 Floating clamp mechanism E+, E2, 2nd work piece W'O Patent applicant Toyota Industries Corporation Type Attorney Patent attorney
Thank you 1) Hiroshi ■ C N , j,,,,, (--Utori□1 i 71 1 l- da\ ya [Ino,・□

Claims (1)

[Scope of Claims] l The relative rotation and the contact pressure under the axial thrust generate frictional heat in the contact area of the pair of workpieces to cause plastic deformation, and the pair of workpieces are joined by sudden rotation stop. In the friction welding machine, an auxiliary centering clamp mechanism for clamping the non-rotating workpiece of the pair of workpieces from both sides and holding it in a predetermined position is provided in the vicinity of the contact area of the workpiece. A floating clamp mechanism is provided at the rear of the auxiliary centering clamp mechanism for clamping and holding the non-rotating workpiece from both sides following the curve of the workpiece. Friction welding machine. 2 The auxiliary centering clamp mechanism consists of 1 a slide base arranged horizontally on the upper surface of the frame perpendicular to the contact pressure direction of the work piece, and a pair of fixing brackets fixed to both ends of the slide base. A pair of movable brackets are supported on a slide base so as to be able to reciprocate toward both sides of the work piece, a pair of clamp claws are attached to opposing surfaces of both movable brackets, and a movable bracket is supported between the two fixed brackets and between the fixed brackets. 2. The friction welding machine according to claim 1, comprising an equalizer link mechanism articulated with the bracket, and a clamp cylinder that operates the equalizer link mechanism. 3. The floating clamp mechanism includes a slide base disposed in a horizontal direction perpendicular to the contact pressure direction of the work piece against the upper surface of the frame, and a slide base that is supported so as to be reciprocatingly movable toward both sides of the work piece with respect to the slide base. a pair of movable brackets, a pair of clamp rings that are fixed to the rear end of the slide base facing each other and actuate the movable brackets, and a clamp ring that is movable relative to the opposing portions of the movable brackets; The friction welding machine according to claim 1, wherein the friction welding machine comprises a pair of floatingly supported clamp claws.