JP2646817B2 - Welding equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a welding apparatus capable of maintaining a cutting margin of a component attached to an end of a work at an optimum value.

[Prior Art] An axle housing, which is one of the traveling parts of a vehicle,
It is a central component of the axle, where the final reduction gear, drive shaft, brakes, wheel bearings, suspension springs, etc. are mounted. Although there are various types of axle housings, a banjo type in which a large hole is formed in the center is often used today. An end rear axle housing is press-fitted into both ends of the axle housing, and the press-fitted end rear axle housing is welded to the axle housing.

FIG. 10 and FIG. 11 show a welding device for welding the axle housing 1 and the end rear axle housing 2. In the figure, reference numeral 5 denotes a bed, on which a head stock portion 6 and a tail stock portion 7 are provided. The head stock unit 6 is fixed to the bed 5. The tail stock unit 7 is slidable with respect to the bed 5. In the pre-process, the end rear axle housing 2 is press-fitted into both ends of the axle housing 1. The axle housing 1 into which the end rear axle housing 2 is press-fitted is loaded with a loading device 8
And is conveyed between the head stock unit 6 and the tail stock unit 7. The axle housing 1 transported between the head stock part 6 and the tail stock part 7 is pressed by the movement of the tail stock part 7. That is, the axle housing 1
It is gripped by the head stock part 6 and the tail stock part 7.

In this case, the total length of the axle housing 1 is measured by the measuring device 9 provided in the tail stock portion 7.
This is for maintaining the cutting allowance of the end rear axle housing 2 at the time of machining performed in a later step optimally. That is, when the axle housing 1 and the end rear axle housing 2 are welded, the entire length of the axle housing 1 contracts due to heat input by arc welding. The length from the end face of the end rear axle housing 2 to the end face of the other end rear axle housing 2 needs to be long in advance, and the total length of the axle housing 1 included in the end rear axle housing 2 is measured before welding by the welding torch 10.

When the welding of the axle housing 1 and the end rear axle housing 2 is completed, the axle housing 1 is sent to a machining process and the end rear axle housing 2
Of the end face 2a, the sub-plate face 3, and the inner peripheral face of the hole 4 are cut.

[Problems to be Solved by the Invention] However, in the case of the welding apparatus as shown in FIGS. 10 and 11, the entire length of the axle housing 1 into which the end rear axle housing 2 is press-fitted is measured to cut the end rear axle housing 2. Since it is trying to secure the cutting allowance to an optimum value, the cutting allowance has been extremely varied on the left and right. That is, since the axle housing 1 is bilaterally symmetric about the hole 4, even if the entire length of the axle housing 1 is measured, the distance from the center to the end surface of one end rear axle housing 2 may be significantly different. .

Therefore, in such a state, the axle housing 1
When the end rear axle housing 2 is welded to the end rear axle housing 2, only the cutting amount of one end rear axle housing 2 is significantly increased.
There is a possibility that the cutting load at the time of cutting of the workpiece becomes large and the machine tool is damaged. If the cutting amount of one end rear axle housing 2 is significantly large, the strength of the ed rear axle housing 2 becomes small due to a decrease in wall thickness, and the design strength cannot be satisfied.

This problem is evident when the axle housing 1 and the end rear axle housing 2 are welded and machined, and the defective product has to be discarded.

As described above, it is very important to optimally maintain and manage the cutting allowance of the end face of the end rear axle housing 2. However, the welding between the axle housing 1 and the end rear axle housing 2 is performed by rotating the axle housing 1 around the axis.゜ It was necessary to rotate, and it was difficult to newly arrange the centering device of the axle housing 1 because of interference with the loading device 8 and the axle housing 1.

The present invention focuses on the above problems, and provides a welding apparatus that can perform centering of a workpiece before welding and can maintain a cutting allowance of a component attached to both ends of the workpiece at an optimum value. The purpose is to do.

[Means for Solving the Problems] A welding apparatus according to the present invention for this purpose, comprising: gripping means for pressing and gripping a workpiece having components attached to both ends by pressing from both sides; and a workpiece having the component attached thereto. Transport means for transporting the workpiece to the grip means, and centering means for centering the workpiece with respect to the grip means by expanding a claw provided in the transport means and inserted into a hole formed in a central portion of the work. Measuring means for measuring a distance from a center of a hole of the work to an end surface of the component in a state where the work is positioned by the centering means provided on the gripping means; and A welding torch means for welding the workpiece and the component when the distance to the end face is within an allowable value.

[Operation] In the welding device configured as described above, the work having the components attached to both ends is transported to the gripper by the transporter. A centering means is provided on the gripping means for transferring the work, and before the transfer by the transfer means to the holding means, a claw of the centering means is inserted into a hole of the work, and the work is centered by expanding the claw. Is performed. When the work is centered, the work is gripped from both sides by the gripping means.

Since the gripping means is provided with a measuring means, the distance from the center of the hole of the work to the end face of the component is measured in a state where the workpiece is in the state of the sinking when the work is gripped by the gripping means. With this, the distance from the center of the work to the end face of one part and the distance from the center of the work to the end face of the other part are grasped, and whether a large offset occurs in the cutting allowance of any part is determined. Can be determined.

When the workpiece gripped by the gripping means has a distance from the center of the hole of the workpiece to the end face of the component within an allowable value,
The work and the component are welded by the welding torch means. When the distance from the center of the hole of the workpiece to the end face of the component is within the allowable value, welding by the welding torch means is not performed. If the measured length is other than the allowable value, the work is once taken out of the welding apparatus and the mounting position of the component is corrected.

As described above, by providing the centering means in the transfer means, interference between the work and the centering means at the time of welding is prevented, and the distance to the component can be measured based on the center of the hole of the work. Therefore, a remarkable increase in the cutting load and a decrease in the strength of the part due to excessive cutting of the part are eliminated.

[Example] Hereinafter, a preferred embodiment of the welding apparatus according to the present invention,
This will be described with reference to the drawings.

1 to 9 show an embodiment of the present invention. In the figure, reference numeral 21 denotes an axle housing as a work, and reference numeral 22 denotes an end rear axle housing as a part. At the center of the axle housing 21, a sub plate 24 is mounted.
At the center of 24, a mounting hole 23 is formed. 31 is axle housing 21 and end rear axle housing
22 shows a welding device for welding 22. The welding device 31
Stand 41, gripping means 51, transport means 61, centering means 7
1, a measuring means 91 and a welding torch means 101 are provided.

The holding means 51 is provided on the gantry 41. Gripping means
Reference numeral 51 denotes a left slide unit 52, a head stock 53, a right slide unit 54, and a tail stock 55. The left slide unit 52 and the right slide unit 53 are fixed to the gantry 41 side, and both are arranged so as to face each other with a gripping means 51 described later as a center. The headstock 53 is slidably held by the left slide unit 52, and the headstock 53 is
The hydraulic cylinder 52a of 52 is capable of moving forward and backward with respect to the transport means 61. The tailstock 55 is slidably held by the right slide unit 54, and the tailstock 55
Is movable forward and backward with respect to the transport means 61 by the hydraulic cylinder 54a of the right slide unit 54.

The head stock 53 has a rotating shaft 53a, and the tail stock 55 has a rotating shaft 55a. In this embodiment,
The rotation shaft 53a functions as a rotation drive shaft, and the other rotation shaft 55a functions as a driven shaft. The headstock 53 and the tailstock 55 press the axle housing 21 pressed by the end rear axle housing 22 from both sides while approaching each other, and the axle housing 21
Is to be gripped. During welding, the gripped axle housing 21 is rotated by the driving force of the rotating shaft 53a.

A transport unit 61 is disposed between the left slide unit 52 and the right slide unit 54 of the grip unit 51. The transport means 61 has a function of moving the axle housing 21 to the idle stations 32 and 33, the welding station 34, and the unloading station 35. The transport means 61 has an air cylinder 63 for moving a support 62 that receives the axle housing 21 in the horizontal direction, and an air cylinder 64 for moving the support 62 up and down.

The transfer means 61 is provided with a centering means 71 for centering the axle housing 21. The centering means 71 includes a pawl 72, as shown in FIGS.
Claw holder 73, taper cam 74, rod 75, rod holder 7
6. It has an air cylinder 77 and a cradle 78. The rod holder 76 is fixed to the support table 62 of the transfer means 61, and the rod 75 is slidably held in the rod holder 76 in the vertical direction. The rod holder 76 is a bush with high lubricity
The rod 75 is configured to smoothly move in the axial direction by sliding contact with the bush 76a. An oil seal 76b is provided at the top of the rod holder 76 to prevent foreign matter from entering the sliding surface. Below the rod 76, an air cylinder 77 fixed to the rod holder 76 is located. The rod 76 and the air cylinder 77 are connected via a connecting tool 79 having an automatic centering function.

On both sides of the top of the rod 75, claws 72 are respectively arranged. A pedestal 78 for receiving the sub plate 24 of the axle housing 21 is disposed outside each of the claws 72. Claws 72
Are fixed to the claw holder 73. The inside of each claw holder 73 can be in sliding contact with the tapered surface 73a of the tapered cam 74 on the tapered surface 73a. At the top of the rod 75, a tapered cam 74 having a T-shaped cross section is fixed.
74 is fitted inside the claw holder 73 so as to be slidable.
When the rod 75 is pushed up by the air cylinder 77, the claw 72 moves radially outward. That is, the pawl 72 is expanded by the raising of the rod 75. Conversely, when the rod 75 is pulled down by the air cylinder 77, the pawl 72 moves inward in the radial direction. When the pawl 72 is in the expanded state, it comes into contact with the inner peripheral surface of the hole 23 at the center of the axle housing 21, whereby the axle housing 21 is centered with respect to the gripping means 51. The taper angle of the rod 75 and the taper angle of the taper cam 74 are the same, and the amount of expansion of the left and right claws 72 is kept uniform during centering.

Measuring means 91 is provided on the left and right slide units 52, 54 of the gripping means 51. The measuring means 91 is a measuring rod
It comprises a detection unit 92 and a detection unit 93. A length measuring rod 92 is movably inserted into the detecting unit 93. On the left slide unit 52 side, both ends of the measuring rod 92 are headstock
On the right slide unit 54 side, both ends of the length measuring rod 92 are supported by tail stock 55. The detection unit 93 fixed to the left slide unit 52 measures the displacement of the headstock 53 with respect to the center of the centering means 71, and the detection unit 93 fixed to the right slide unit 54 adjusts the tailstock with respect to the center of the centering means 71. 55 displacements are measured. Each detector
93 converts the displacement amount of each stock 53, 54 into an electric signal, and the electric signal from each detecting unit 93 is input to the control unit 111.

The headstock 53 of the gripping means 51 has a welding torch means.
101 is installed. The welding torch means 101 has a torch shift unit 102, a torch elevating unit 103, and a welding torch 104. The torch shift unit 102 is fixed to the head stock 53. The torch shift unit 102 includes a torch elevating unit 103
The torch elevating unit 103 can move forward and backward with respect to the centering means 71 by the positioning air cylinder 102a of the torch shift unit 102. Torch lift 10
3 is equipped with a welding torch 104,
104 can be moved up and down by a positioning air cylinder 103a of the torch elevating unit 103. The torch shift section 102 and the torch elevating section 103 of the welding torch means 101 are connected to the welding torch 10
4 has a function of positioning the front end of the axle housing 21 at the joint between the axle housing 21 and the end rear axle housing 22.

The control unit 111 is provided with a hole 23 in the center of the axle housing 21
If the distance from the center of the end to the end face of each end rear axle housing 22 is within the allowable value, the welding torch means 10
1 outputs a signal indicating that the axle housing 21 and the end rear axle housing 22 are to be welded. Conversely, if the distance L ₁ from the center X of the central portion of the hole 23 to the end surface 22a of each end rear axle housing 22 of axle housing 21 is other than tolerance, stop welding,
A command to output the axle housing 21 to the transport means 61 is output.

Next, the operation of the above welding device will be described.

First, the end rear axle housing 22 is press-fitted into both ends of the axle housing 21 by a press-fitting device (not shown) located in the preceding process. When the press-fitting of the end rear axle housing 22 is completed, the axle housing 21 is carried into the welding device 31 and set in the idle station 32. Axle housing 21 is idle station
When set to 32, the axle housing 21 is
The axle housing 21 is set in the next idle station 33 by moving through a series of operations of ascending, advancing, descending, and retreating 61. When the axle housing 21 is set in the idle station 33, the pawl 72 of the centering means 71 is located immediately below the hole 23 of the axle housing 21.
72 is inserted into the hole 23 of the axle housing 21. When the rod 75 of the centering means 71 is pushed up by the air cylinder 77 in this state, the pawl 72 moves radially outward, and the axle housing 21 is centered by the expansion of the pawl 72.

When the axle housing 21 is centered, the axle housing 21 is transferred to the welding station 34 by the transfer means 61. Axle housing 21 is a welding station
When positioned at 34, the axle housing 21 is centered by pawls 72. In this state, the holding means 51
Is moved by the left slide unit 52 toward the centering means 71, and the tail stock 55 is moved by the right slide unit 54 toward the centering means 71. As a result, the headstock 53 and the tailstock 55 approach each other, and the axle housing 21 into which the end rear axle housing 22 is press-fitted has a rotation shaft 53a of the headstock 53 and a rotation shaft 55a of the tailstock 55.
Is pressed and gripped.

Here, the length measuring rod 92 of the measuring means 91 moves with the movement of the head stock 53 and the tail stock 55, and the distance from the center of the hole 23 of the axle housing 21 to the end face of one end rear axle housing 22; The distance from the center of the hole 23 of the axle housing 21 to the end surface of the other end rear axle housing 22 is measured. That is, the stroke amount of the head stock 53 and the stroke amount of the tail stock 55 are distribution measurement values of the axle housing 21. The measurement signal from each detector 93 is transmitted to the controller 111
And the control unit 111 compares the preset measurement value with the input measurement value. The preset value is a value in consideration of shrinkage of the entire length of the axle housing 21 at the time of welding. With this set value, it is possible to maintain the cutting allowance in the cutting of the end surface of the end rear axle housing 22 at an optimum value. Becomes

Results of the comparison of the set value of the control section 111 and the measured value, when the distance L ₁ from the center X of the hole 23 of the axle housing 21 to the end face 22a of the end rear axle housing 22 is determined to other tolerances, the axle The housing 21 is not welded to the rear axle housing 22 and the gripping means 51
The axle housing 21 is released from gripping by the
Moved to 35. When the axle housing 21 is set in the unloading station 35, the axle housing 21 is transported from the welding device 31 by a transport device (not shown), and is transported into the reworking process. In the reworking step, the end rear axle housing 22 is removed from the axle housing 21, and the press-fit position of the end rear axle housing 22 is corrected.

Results of the comparison of the set value of the control section 111 and the measured value, if the distance L ₁ to the end face 22a of the end rear axle housing 22 from the center X of the hole 23 of the axle housing 21 is determined to within the tolerance, the axle A signal indicating that the housing 21 and the end rear axle housing 22 are to be welded is transmitted to the control unit 11.
1 is output to the welding torch means 101. When the welding signal is input to the welding torch means 101, the rod 75 of the centering means 71 is lowered by the air cylinder 77, and the pawl 72 is pulled out of the hole 23 of the axle housing 21. Thereafter, the welding station 35 moves away from the centering means 71 with the retreat of the transport means 61, and the interference between the axle housing 21 and the centering means 71 is avoided.

When the centering means 71 moves away, the torch shift unit 10
2 and the torch elevating unit 103 are operated, and the tip of the welding torch 104 is positioned toward the joint between the axle housing 21 and the end rear axle housing 22. Welding torch
When the positioning of 104 is completed, a welding wire is fed from the tip of welding torch 104, and welding of axle housing 21 and end rear axle housing is started. At the same time, the axle housing 21 is rotationally driven by the rotating shaft 55a of the gripping means 51 being gripped, and the entire circumference of the axle housing 21 and the end rear axle housing 22 is welded. Note that this full circumference welding is not limited to CO ₂ welding, but can be performed by another welding method such as laser welding.

When the welding of the axle housing 21 and the end rear axle housing 22 is completed, the conveying means 61 rises and the gripping of the axle housing 21 by the gripping means 51 is released.
In this state, the axle housing 21 is received by the raising of the transport means 61. When the axle housing 21 is supported by the transporting means 61, the headstock 53 and the tailstock 55 of the gripping means 51 retreat, and the headstock 53 and the tailstock 55 return to the return position. When the retraction of the head stock 53 and the tail stock 55 is completed, the axle housing 21 is set to the unloading station 35 by the transport means 61. The axle housing 21 set in the unloading station 35 is transported by a transporting means (not shown) to the next step in which machining is performed. In the next step, the axle housing
End face of end rear axle housing 22 welded to 21
The machining of 22a is performed.

In this case, the distance from the center X of the hole 23 of the axle housing 21 to the end face 22a of the end rear axle housing 22 is measured by the welding device 31 in the previous process, and only those whose distance is within an allowable value are welded. In this machining, the cutting allowance of the end rear axle housing 22 is maintained at an optimum value. Thus, the total length L ₀ of the axle housing 21 in the present invention are not considered.

Therefore, one end rear axle housing 2
The amount of cutting of the end rear axle housing 22 is not significantly increased, and an increase in the cutting load when cutting the end rear axle housing 22 and a decrease in the strength of the end rear axle housing 32 are eliminated.

In the present embodiment, the control unit 11 is applied to the axle housing 21 in which the left and right lengths are the same with respect to the center of the hole 23.
By setting the set value to 1 to a predetermined length, the cutting allowance of the end rear axle housing 22 can be maintained optimally. Further, after welding, the center X of the hole 23 of the axle housing 21 is moved to the end rear axle housing.
By re-measuring the distance of the 22 to the end face 22a, the distribution accuracy is completely guaranteed.

In addition, in the conventional device, when measuring the length of the axle housing, the fixed headstock portion is used as a reference, so the center when loading and unloading the axle housing is offset by 1/2 of the total length difference. In the case of a long axle housing, stable unloading may be difficult, but in the case of this embodiment, even if a long axle housing is inserted, the center can be used as a reference. Can be carried out.

[Effect of the Invention] As described above, when the welding apparatus according to the present invention is used, the centering means for centering the work by expanding the pawls on the transfer means for transferring the work to which the parts are attached to the holding means. In the state where the work is centered by the centering means, the distance from the center of the hole of the work to the end face of the part is measured by the measuring means, and when the measured distance is within the allowable value, the work is performed by the welding torch means. And the parts are welded, the following effects can be obtained.

(B) Since welding is performed only on the parts whose distance from the center of the hole in the work to the end face of the part is within the allowable value, the distance from the center of the work to the end face of the part is determined by The optimum distance can be set in consideration of the distance. Therefore, there is no variation in the cutting allowance of the part at the time of machining in the post-process, and it is possible to prevent an increase in the cutting load and a decrease in the strength of the part due to excessive cutting of the part.

(B) If the distance from the center of the hole of the work to the end face of the part is not the allowable value, welding between the work and the part is prevented beforehand, so the mounting position of the part on the work can be corrected. , Can be used as product. Therefore, there is no need to dispose of the product as in the related art, and the defective rate of the product can be greatly reduced.

[Brief description of the drawings]

 1 is a plan view of a welding apparatus according to one embodiment of the present invention, FIG. 2 is a front view of the apparatus of FIG. 1, FIG. 3 is a side view of the apparatus of FIG. 1, and FIG. 5 is a cross-sectional view of FIG. 4, FIG. 6 is a plan view of the vicinity of the measuring means in FIG. 1, FIG. 7 is a front view of FIG. 6, and FIG. 9 is a side view of FIG. 8, FIG. 10 is a plan view of a conventional welding apparatus, and FIG. 11 is a front view of the apparatus of FIG. 21 Workpiece (axle housing) 22 Parts (end rear axle housing) 23 Workpiece hole 31 Welding device 51 Gripping means 61 Transporting means 71 Centering means 72 Claws 91 Measuring means 101 ... Welding torch means 111 ... Control unit

Claims (1)

(57) [Claims] 1. A gripping means for pressing and gripping a workpiece having components attached to both ends thereof from both sides by pressing from both sides, a transporting means for transporting the workpiece having the components attached thereto to the gripping means, and provided on the transporting means. A centering means for centering the work with respect to the gripping means by expanding a claw inserted into a hole formed at the center of the work, and positioning the work by the centering means provided on the gripping means. Measuring means for measuring the distance from the center of the hole of the work to the end face of the component in a state where the work is performed, and the work if the distance from the center of the hole of the work to the end face of the component is within an allowable value. A welding apparatus comprising: welding torch means for welding with a part.