JPS59152059A - Grinder for welded part of steel pipe, etc. - Google Patents

Abstract

PURPOSE:To economize man's labor and prevent excessive loading for a grindstone by installing an automatic reversal stopper for operating a normal/reverse revolution switching lever for a driving wheel installed onto a feeding-motor supporting board and controlling the revolution speed of a motor according to the cutting-in amount of the grindstone. CONSTITUTION:When a grindstone 10 makes a circuit around the outer periphery of a steel pipe 11, the top edge of a switching lever 45 is attached onto the top edge of a stopper 48, and the lever is bent until it clears a cam 40, and after the lever passes the cam a little, the lever passes a projected edge part 42, and then the lever 45 is turned by two repulsive forces of the stopper 48 and a spring 43, and the reverse cam 40 is turned by about 90 deg. with a valve body 37, and then a reverse valve V4 is switched and the motor 6 and a driving wheel 7 starts reversal, and a motor supporting base 5 is driven reversely. When the grindstone cuts-in and the resistance increases, the grindstone 10 runs over a welded part 12, and a motor 8 stops, and the driving wheel slips, and then the pressure in an air chamber increases, and the valve piece is pushed-in, and the amount of compressed air supplied to the motor 6 is reduced, and the revolution speed of the driving wheel 7 is reduced. Therefore, automation of the apparatus is permitted.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a grinding device for grinding the outer periphery of a welded portion of steel pipes whose abutted portions are welded.

Connecting steel pipes, which are made by butting steel pipes together and welding along the butt, are inspected using methods such as color checking to look for defects in the weld, but as a pretreatment, weld bead bulges are checked. It needs to be scraped off.

By the way, when trying to grind large-diameter connecting steel pipes that cannot be ground with a grinder or welds of butt-welded connecting steel pipes on-site, most of the conventional methods have been inefficient methods such as using a hand grinder. Since it is a manual process, it takes eight hours to grind, and it is difficult to grind the welded part smoothly and uniformly. Furthermore, in the case of manual work, vibration problems for workers and hygiene problems due to dust occur.

In an attempt to solve these problems, the applicant of the present application has already provided a processing device for steel pipes that can automatically grind the outer periphery of a welded part. (Tokuko Showa 56-2
(Japanese Patent Publication No. 668 and Japanese Unexamined Patent Application Publication No. 56-9158) The above inventions all include a first pipe that is movable in the circumferential direction along the outer periphery of the steel pipes. a second connector, a motor support mounted between one end of the first and second connectors, and a grinding motor that is supported by the motor support and whose position can be adjusted in the radial direction of the steel pipes. and a disk-shaped grindstone rotationally driven by the motor; It is composed of a feeding motor attached between the other ends of the second connector, and a drive wheel whose outer periphery partially contacts the outer periphery of the steel pipes and is driven by the feeding motor, The first drive wheel is driven by the feed motor. The welded portion is ground by a grindstone while moving the second connector and the motor support in the circumferential direction of the steel pipes.

Therefore, it is superior to manual grinding in that it can grind automatically and efficiently, but in the case of the above-mentioned known devices, they automatically stop after one rotation while grinding the outer periphery of steel pipes. Therefore, the operator must operate a predetermined part of the stopped grinding device to start the motor.

Therefore, it is necessary for the operator to constantly monitor the grinding device, which poses a problem in that the effect of saving manpower is weak.

The purpose of this invention is to solve the above-mentioned problems. After grinding the steel pipes by going around the outer circumference of the steel pipe, the grinding wheel automatically makes a certain cut and the feed motor is reversed. The present invention provides a grinding device that repeatedly rotates around the outer periphery of steel pipes in the opposite direction.

That is, the present invention provides a first tube that is movable in the circumferential direction along the outer periphery of the steel pipes. a second connector, a motor support mounted between one end of the first and second connectors, and a grinding tool that is supported by the motor support and whose position can be freely adjusted in the radial direction of steel pipes. a motor, a disc-shaped grindstone rotationally driven by the motor, and the first. In a grinding device configured with a feed motor attached between the other ends of the second connector and a drive wheel whose outer periphery partially contacts the outer periphery of the steel pipes and is driven by the feed motor, the motor is supported. A switching lever that rotates the drive wheel in the forward or reverse direction is installed at an appropriate location on the stand, and an automatic reversal stopper that contacts the switching lever and moves the lever in the forward or reverse direction is installed on the outside of the steel pipes. There is a grindstone feeding means between the support stand and the grinding motor that moves the motor a predetermined amount to cut the grindstone into the weld when the drive wheel rotates in reverse; If a control means is provided to control the rotational speed of the feed motor accordingly, it can be fully automated.

Since this invention has the above-mentioned configuration, the grinding device automatically repeats normal and reverse rotation along the circumferential direction of the steel pipes, and when it has a grindstone feeding means, cuts the grindstone into the part to be ground. Since only manpower is required for starting and stopping, the effect of saving manpower is significant.In addition, if a control means is provided, the rotational speed of the feed motor changes according to changes in the cutting resistance of the whetstone, This has the effect of not forcing people to overdo it.

An embodiment of the present invention will be described below with reference to the accompanying drawings.

As shown in FIGS. 1 and 2, the first wire is wound around the outer circumference of the steel pipe 11 at opposing positions. The second connector 1.2 includes a plurality of links 3 connected to each other and a roller 4 attached to each connecting shaft of the links 3, and allows the connectors 1, 2 to run along the outer periphery of the steel pipe. Then, each roller 4 comes into contact with the outer periphery of the steel pipe. Furthermore, the lengths of each of the connectors 1 and 2 can be adjusted.

One end of the first connector 1 and the second connector 2 is connected to a position facing the motor support 5, and the other end is connected to a position facing the outer periphery of the feed motor 6. , a drive wheel 7 having a rubber tire on the outer periphery is attached to the rotating shaft of the feed motor 6.
is fixed.

The motor support stand 5 has wheels 1 in contact with the outside of the steel pipe 11.
3, a grinding motor 8 is fixed on a support stand 5, and a disc-shaped grindstone 1o is attached to a rotating shaft 9 of this motor 8.

The motor 8 is attached to a motor case 14 as shown in FIGS. 2 to 4, and dovetail grooves 15 are formed on both sides of the motor case 14 as shown in FIG. On the other hand, a pair of guide plates 16 are attached to both sides of the upper part of the motor support base 5, and by fitting the guide plates 16 into the dovetail grooves 15, the motor 8 can freely slide vertically with respect to the motor support base 5. It becomes. Further, a connecting plate 17 is attached to the upper part of the pair of guide plates 16, and the lower end of the feed screw 8 screwed into the screw hole in the center of the connecting plate 17 is rotatably connected to the motor case 14. ,
Moreover, since the screw 18 and the case 14 are attached so as to move up and down together, by rotating the feed screw 18, the height of the motor 8 with respect to the motor support base 5 can be freely changed.

As shown in FIGS. 3 and 4, a pinion gear 21 is attached to the outer periphery of the feed screw 18 through a clutch 20, and a rack gear 22 is meshed with this gear 21. This rack gear 22 has a knee ring 23 fixed to the motor case 14.
This cylinder 23 is a spring return type and has a return spring 26, and when the piston 24 is pushed by compressed air, the rack gear 22 moves the pinion gear 21 to the feed screw. 18 to move the motor 8 together with the grindstone 10 in the radial direction of the steel pipe 11.

The feed screw 18 also has a nut 1 as a stopper.
9 is for installation.

The feed motor 6 and the grinding motor 8 are air motors, and 30 in FIGS. 5 to 8 is a valve box provided at the rear end of the grinding motor 8.

In this valve box 30, 31 is a compressed air supply port,
32 is a valve body of a manually operated stop valve v2. 33 is an air chamber communicating with the stop valve v2, and 34 is moved to a position where the air pressure in this chamber 33 and the spring 35 are balanced, and the feed motor 6
This is the valve body of the automatic control valve v3 that adjusts the air heading to.

V is a feed stop valve, and 37 is a valve body of a reverse valve v4 that rotates the motor 6 in the forward and reverse directions.

Reference numeral 40 in FIGS. 5 and 8 indicates a reverse cam that is integrated with the valve body 37 of the reverse valve v4, and has a planar shape as shown in FIG. 9.

This cam 40 is located in a recess 41 in the lower part of the valve body 30, and a spring 4 is attached to the chevron-shaped end 42 of the cam 40 on the end face of the recess 41.
3, a ball 44 is provided which is pressed against the ball 44 to hold the cam 40 and the valve body 37 in the normal rotation position and the reverse rotation position.

45 is a switching bar which is rotatably attached to the lower part of the valve box 30 by a shaft 46. A long hole 46' is provided in a part of this lever 45, and the pin 47 on the lower surface of the cam 40 is loosely fitted into this long hole 46'. It is configured to allow large rotations. Note that the valve box 3o may be provided on the motor support stand 5.

” This lever 45 is moved by an automatic reversal stopper 48 fixed to the outer periphery of the steel pipe 11 as shown in FIG.

This stopper 48 is made of a plate spring, and its rear end is fixed to a band 49 wound around and fixed to the steel pipe 11. however,
This stopper 48 may be fixed to the steel pipe 11 using, for example, a permanent magnet other than the band 49.

A guide hand 52 is also fixed to the outer periphery of the steel pipe 11 at the rear of the support stand 5, and the support stand 5 is fixed as shown in FIGS. 2 and 4.
Guide rollers 29 fixed to the rear ends of a pair of left and right bolts 27 that are adjustable on both sides of the belt are brought into contact with the rear side of the guide band 52 as shown in FIG.

Figure 10 is a circuit diagram, and 50 in the figure is a compressed air source consisting of a compressor, receiver tank, etc., and the air supply hose connected to the compressed air outlet is connected to the supply port 31 shown in Figure 6, etc. 31 reaches the motor 6 via the stop valve v7, control valve v3, and reverse valve v4 of the feed motor 6, and the reverse valve v4 is connected to the cylinder 2.
The passage leading to 3 is also connected.

The compressed air source 5o also supplies air to the grinding motor 8 via the grinding wheel stop valve v2, but in the middle of this, air is supplied from the air chamber 33 to the automatic control valve v3 as shown in FIG. It is designed to apply air pressure.

To explain the operation of the above embodiment, FIGS.
As shown in the figure, the connectors 1 and 2 are attached to the steel pipe 11, the grindstone 10 is positioned outside the welded part 12, and the feed screw 18 is turned using the handle to tighten the screw 18 into the motor case 14.
At the same time, the grindstone 10 is moved in the radial direction of the steel pipe 11 to bring it into contact with the welded portion 12 .

At this time, a gap is provided between the lower end of the nut 19 and the upper surface of the connecting plate 17 to allow the outer periphery of the grindstone 10 to descend to the same surface as the outer periphery of the steel pipe 11.

In this state, when the stop valve V2 is first opened and then the stop valve V is opened, the compressed air from the compressed air source 50 flows to the air motors 8, 6, rotates the grindstone 10, and drives the drive wheel 7. , the steel pipe 1 while grinding the welded part 12.
Move along the circumference of 1.

When the grindstone 10 and the like go around the outer circumference of the steel pipe 11 in this way,
The tip of the switching lever 45 hits the tip of the stopper 48, bends it slightly until it passes over the chevron-shaped end 42 of the cam 40, and then immediately after passing the chevron-shaped end 42, the two repulsions of the stopper 48 and the spring 43 lever 45 by force
is rotated from the solid line position in FIG. 9 to the chain line position and rotated about 90 degrees together with the reverse cam 40 or the valve body 37, so the reverse valve v4 is switched and the motor 6 and drive wheels 7 rotate in the reverse direction. The motor support stand 5 and the like begin to move backward. If the repulsive force of the stopper 48 and the spring 43 were not utilized, the reverse valve V4 would stop at the neutral position and the motor 6 would stop.

When reverse valve v4 switches as described above, cylinder 2
Since air pressure is applied to the gear 3, the screw 24 inside compresses the spring 26 and moves forward, causing the rack gear 22 to rotate the pinion gear 21. At this time, the one-way clutch 20 is connected to the gear 28.
1 and a feed screw 18 are combined and rotated, and the screw 18 is lowered by an appropriate amount to cut the grindstone 10 into the welded portion 12.

In this state, when the grinding wheel 10 etc. kneels in the reverse direction on the steel pipe 11 and the tip of the lever 45 hits the back side of the stopper 48, the reverse valve v4 switches, the driving wheel 7 rotates forward, and the grinder 10 etc. rotates on the steel pipe. 11 in the positive direction.

Further, when the reverse valve v4 is switched as described above, the compressed air in the cylinder 23 is exhausted, and the piston 24 is returned to its original position by the spring 26. At this time, pinion gear 21
is reversed, but the feed screw 18 does not turn because the clutch 2° slips.

By repeating the action described above, the grindstone 10 etc. repeatedly go back and forth to grind the welded part 12, and when the surface of the welded part 12 becomes flush with the outer peripheral surface of the steel pipe 11, - Natsu 1
9 hits the outer surface of the connecting plate 17 and the grindstone 10 no longer cuts, so at this stage the stop valves V, , v2 are closed to end the grinding.

In addition, during the above-mentioned grinding, if the grinding wheel 10 cuts into a large built-up part of the welding part 12 and the resistance becomes large, if the motor 6 is running at a constant speed, the grinding wheel 10 will cut into the welded part. 12, the motor 8 stops, and the drive wheel 7 slips.

As a result, the pressure inside the air chamber 33 in FIG. The amount of air is restricted and the rotational speed of the drive wheels 7 is slowed down.

In addition, in the part of the weld 12 with less build-up, the resistance applied to the grinding wheel 10 becomes smaller, and the rotation of the drive wheel 7 becomes faster, so the pressure in the compressed air chamber 33 decreases, and the action of the spring 35 of the control valve V3 causes the valve v1 to The amount of air flowing toward the vehicle increases, and the rotation of the drive wheels 7 becomes faster.

As is clear from the above-mentioned embodiments, the grinding device of the present invention has a grinding wheel, a support stand equipped with a motor that drives the grinding wheel, and a drive wheel that, together with a connecting tool, automatically move back and forth along the circumference of the steel pipe. Since it is a return mechanism, it requires human labor at the time of starting and stopping, but there is no need for human labor at all during that time.

Further, since the rotation of the drive wheel is controlled according to the resistance applied to the grindstone, the support base moves at a moving speed suitable for the cutting depth of the grindstone. Therefore, there are effects such as not causing strain on the grindstone.

In the embodiment, an air motor is used as the grinding motor and the feeding motor, but an electric motor may be used instead of the air motor, and in this case, the valve vI.

v2. (3) etc. become switches, the cylinder 23 is replaced with an electromagnet, and the control valve v3 becomes a rotational speed control device for the feed motor.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an embodiment of the grinding device of the present invention;
Fig. 2 is a partially longitudinal side view of the same as above, Fig. 3 is an enlarged longitudinal sectional front view of the main part of the same, Fig. 4 is a partially cross-sectional enlarged plan view of the same as above, Fig. 5 is a partially longitudinal section of the grindstone drive part 1. 6 is an enlarged cross-sectional plan view taken along the line I-I in FIG. 10 is a partial cross-sectional enlarged bottom view of the reverse valve operating section (illustrated circuit diagram). 1... First connector, 2... Second connector, 5... Motor support stand, 6 ... Feeding motor, 8... Grinding motor, 11... Steel pipe, 12... Welded part, 45...
Switching reno <-148...Automatic reversal stone/N01A・
... Grinding wheel feeding means, B... Control means Patent applicant: Japan Pneumatic Industry Co., Ltd. Agent: Sickle 1) Text - Figure 10 - 339

Claims (1)

[Scope of Claims] 1. First and second connectors movable in the circumferential direction along the outer periphery of the steel pipes; a motor support mounted between one end of the second connector; a grinding motor that is supported by the motor support and whose position can be freely adjusted in the radial direction of the steel pipes;
a disk-shaped grindstone rotationally driven by the motor; In a grinding device configured with a feed motor attached between the other ends of the second connector and a drive wheel whose outer periphery partially contacts the outer periphery of the steel pipes and is driven by the feed motor, the motor is supported. A switching lever for rotating the drive wheel in the forward or reverse direction is installed at an appropriate location on the stand, and an automatic reversal stopper is provided on the outside of the steel pipes to contact the switching lever and move the lever in the forward or reverse direction. Equipment for grinding welded parts of steel pipes. 2. The scope of claims characterized in that a grindstone feeding means is provided between the motor support stand and the grinding motor to move the motor by a predetermined amount and cut the grindstone into the grinding part when the drive wheel is reversed. The apparatus for grinding welded parts of steel pipes according to item 1. 3. A steel pipe according to claim 1, characterized in that the circuit of the feed motor is provided with a control means for controlling the rotational speed of the feed motor in accordance with changes in the cutting resistance of the grindstone. Welding part grinding equipment.