JPS6211982B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a positioning device for the end face of a steel pipe that allows the length of the steel pipe to be accurately set when processing the end face of the steel pipe that is transported along the spindle axis.

Conventionally, when machining the end face of a steel pipe, it is known that, for example, the amount of movement of the steel pipe transferred by a conveyor roller is set using a length measuring pulse counter connected to the roller. If a slip or the like occurs in the steel pipe, accurate positioning cannot be performed, so the position of the end face of the steel pipe varies, resulting in the disadvantage that the amount of cutting of the end face of the steel pipe cannot be determined.

That is, in order to prevent defective products from being produced due to insufficient cutting, it is necessary to allow for a larger amount of cutting than necessary as a margin for positioning, resulting in a problem that the processing time becomes longer. As another method, as seen in known bar processing machines, there is a method of positioning a steel pipe by abutting it against a stopper provided on the processing area side. In this case, especially with large steel pipes, the inertial force associated with the transport of the steel pipe is large, so energy absorption during collision must be taken into account, and the stopper may also be moved in the axial direction to ensure accurate positioning. arise. Another problem was that the stopper had to be retracted once the position was determined.

Furthermore, when the transfer length changes due to differences in the diameter of the steel pipe, the setting position of the stopper must be changed each time, which requires a lot of setup time.

The present invention solves the above-mentioned conventional drawbacks by firmly grasping the outer diameter portion of the steel pipe carried in on the spindle axis, and feeding the grasped steel pipe to the processing machine side along the spindle axis using a feed stand. A detector installed at a fixed position on the processing machine side detects the fixed passing position of the steel pipe end face, and based on this fixed passing position, the distance of the steel pipe end face transferred to the predetermined position set in the processing area is calculated. Positioning is performed accurately through control.

According to the present invention, since the steel pipe is fed while being firmly gripped, there is no deviation due to slipping from the predetermined position, and since the feeding dimensions are reliably controlled, accurate positioning is possible without the need to use a stopper. It became.

Furthermore, even if steel pipes with different diameters are brought in and the setting distance for feeding changes, the setting distance for feeding relative to the diameter of the steel pipe is automatically determined by the operation panel. That is, since it is only necessary to input the designation of the diameter of the steel pipe, there is no need for complicated setup operations, and the operation can be performed quickly and reliably, and the configuration is also extremely simplified.

Examples will be described in detail below with reference to the drawings.

FIG. 1 is an overall view showing a steel pipe feed device arranged along the main axis of a steel pipe end face processing machine.

FIG. 2 is a cross-sectional view taken along the line A-A in FIG. 1, showing the configuration of the feed table of the steel pipe feeding device and the state in which the steel pipe is carried into the grasping device.

A base 1 is arranged at the rear left side of the processing machine along the main axis of the processing machine. Further, a pedestal 3 on which the steel pipe 2 is placed is installed on the left side of the base 1, and a plurality of guide rollers 4 are rotatably provided above the pedestal 3. When the steel pipe 2 is carried in, it is inserted into a grasping device which will be described later, and at the same time, the rear part of the steel pipe is supported by the guide rollers 4 of this pedestal 3.

The guide rollers 4 are designed to be retracted when the steel pipe is fed into the processing machine, its position is determined, and the processing process begins. Furthermore, although not shown in the drawings, this pedestal 3 is provided with a steady roller to prevent the steel pipe from swinging during machining. These steady rest rollers are retracted when the steel pipe is carried in, but come out to support the steel pipe when the processing process begins.

Next, two guide surfaces 5 are formed on the upper surface of the base 1 and are provided parallel to the main shaft axis. Further, a feed table 6 is slidably placed astride the guide surface 5. The feed table 6 is slid in parallel to the spindle axis via a ball screw 8 by a servo motor 7 attached to the end of the base 1.

A grasping device 9 is attached to the feed table 6,
The grasping device 9 is constructed as follows. That is, the bases 10 and 11 are mounted to be slidable in a direction perpendicular to the spindle axis, and the bases 10 and 11 are moved in opposing directions via a screw 13 by a hydraulic motor 12 provided at the end of the feed table 6. slide each. That is, since the bases 10 and 11 are screwed together by threaded portions of the screw 13 in different left and right directions, the bases 10 and 11 repeatedly advance and retreat symmetrically with respect to each other. The bases 10 and 11 are configured such that the forward and backward distance can be calculated according to the rotation angle of the hydraulic motor 12. That is, the diameter of the steel pipe carried into the grasping device is adjusted by the pulse generator 27, which will be described later, provided on the hydraulic motor 12.
This can be determined by the forward and backward movements of 0 and 11. Blocks 14 and 15 are attached to the bases 10 and 11, respectively, and the blocks 14 and 15 have opposite V-shaped recesses and are opposed to each other. Therefore, the steel pipe to be carried in is tightly narrowed along the main shaft axis by this V-shaped recess. In this embodiment, two sets of grasping devices 9 are provided to stably hold the steel pipe.

Next, a processing machine 16 for processing the end face of a steel pipe, for example, a processing machine 16 for thread cutting, has a headstock 18 mounted on a bed 17, and a main shaft 19 rotatably supported on the headstock 18. The main shaft 19 is provided with a through hole that coincides with the main shaft axis, and the steel pipe is inserted through this through hole and positioned on the processing area side. Also, main shaft 1
There are chucks 2 on both ends of 9 for gripping the steel pipe.
0,21 are attached. This chuck 2
0 and 21 conform to a known chuck configuration, and automatically grip the outer diameter portion of the steel pipe by, for example, fluid pressure operation. (Refer to Japanese Patent Laid-Open No. 53-5330.) On the other hand, the stay 22 attached to the end face of the headstock 18 is provided with a detector for detecting the passage of the end face of the steel pipe. This detector is the floodlight 2
3 and a light receiver 24, and detects the position when the end face of the steel pipe passes between the light emitter 23 and the light receiver 24 and blocks the light. Next, on the right side of the bed 17 is a tool rest 25.
is mounted so as to be movable parallel to the main axis direction and in a right angle direction. The tool rest 25 is provided with a turret head 26 to which a plurality of tools can be attached and indexed according to a machining program.

The tool post 25 is controlled by a known numerical control device to perform thread cutting on the end face of the steel pipe.

The present invention is configured as described above and operates as follows. A steel pipe is carried in from above or behind the base 1 using, for example, a crane, and the front part (processing machine side) of the steel pipe is inserted into the grasping device 9, and the rear part is placed on the guide rollers 4. The front part of the steel pipe inserted into the grasping device 9 is connected to a pair of blocks 14,1.
5, it is firmly grasped by the operation of the hydraulic motor 12. As described above, the blocks 14 and 15 are arranged in opposite directions and are moved forward and backward by the screw 13 connected to the hydraulic motor 12. The moving distance of the blocks 14 and 15 is controlled by the hydraulic motor 12.
The rotation angle is calculated by the pulse generator 27 attached to the rotation angle. That is, the diameter of the steel pipe to be inserted is determined by the rotation angle of the hydraulic motor 12.

The signal determined by the pulse generator 27 is applied to a steel pipe positioning control system, shown in block diagram form in FIG. 3, to determine the advancement distance of the steel pipe from a reference point. The steel pipe whose diameter has been confirmed and understood moves forward, and the end face of the steel pipe passes through a detector installed on the processing machine side. When the steel pipe passes this detection position, pulse counting starts from this point and the feeding operation of the steel pipe stops when the distance matches a set distance L determined in advance according to the diameter of the steel pipe. The distance traveled by the steel pipe is read by a linear scale 28 attached to the side surface of the base 1. This pulse signal is applied to the position control circuit 29, where it is compared with a pre-stored set distance, and the result is sent to the speed control circuit 30. (See Figure 5) That is, since the speed signal detected by the tachometer generator 31 of the servo motor 7 is sent to the speed control circuit 30, the position signal from the position control circuit 29 causes the end face of the steel pipe to move within the set distance L. When the positioning point is reached, a command to decelerate from fast forward is automatically applied, and the servo motor is driven to accurately stop and position at the set distance. Although the linear scale 28 is used to determine the position as the steel pipe moves, other methods such as an encoder may be used. Regarding the steel pipe feeding operation, as shown in Fig. 4, the detector 2
3 and 24, the steel pipe is fed at a detectable speed, and after passing, it is transported in rapid traverse, and then decelerated and stopped just before the set position.

Therefore, the set distance of a steel pipe carried into an arbitrary position is automatically determined by the distance L to the set position based on the point of passage of the detectors 23 and 24, so that when carrying in the steel pipe, complicated work such as positioning is not required. No setup work required. When the diameter of the steel pipe changes, the set length L is determined in comparison with the steel pipe diameter as shown in Fig. 5, so the steel pipe diameter can be input using the numeric keys on the operation panel, that is, the keyboard input circuit 32.
Store them in sequence. Accordingly, when the grasping device 9 reads the diameter of the steel pipe, the set length L is automatically determined, so there is no need to manually change the setting conditions each time depending on the type of steel pipe. Furthermore, accidents caused by mistakes such as malfunctions can be prevented, which has a significant safety effect. In the steel pipe positioning control device, the reference position detection signals of the detectors 23 and 24 are input to the RAM through a data input (input interface) 33.
34 and the storage circuit of ROM 35 is performed by CPU 36 (central processing unit). That is, settings such as the steel pipe diameter are stored in the RAM 34 via the keyboard input circuit 32 as a memory whose settings can be changed, and the system control program and sequence control program, which are the basis of the present invention, are stored in the ROM 35. NC for processing along with accurate stop positioning control of steel pipes
An NC machining start command signal is sent to the device via a data output (output interface) 37. That is, when the steel pipe is positioned and stopped, the chucks 20 and 21 are tightened to grip the steel pipe, then the guide roller 4 is retracted, the steady rest roller is extended, and the gripping device 9 is unclamped. The main shaft rotates and the tool post 25 starts processing under NC control. When the machining is completed, the main shaft is stopped by a completion signal, and contrary to the above, the grasping device 9 clamps the steel pipe, the steady rest roller is retracted, the guide roller 4 is extended, and
Subsequently, the chucks 20 and 21 become loose.
Next, the processed steel pipe is quickly returned to its original position together with the feed table 6 by the servo motor 7. Subsequently, the grasping device 9 is unclamped again and the steel pipe is carried out. After being carried out, a new steel pipe material to be processed is carried in again and the above-mentioned operation is repeated. A limit switch 38 is provided to detect the presence or absence of steel pipes when the steel pipes are carried in and out. (Figure 3) This steel pipe presence/absence signal is sent to the data input (input interface) 39, and when a steel pipe machining completion signal is received and the delivery of a new material steel pipe is confirmed, the above-mentioned operation is executed. ing.

By having the present invention configured and operated as described above, even if the steel pipe is brought in with a changed diameter, the steel pipe transfer positioning is automatically performed accurately, so that the work can be carried out safely without fear of erroneous operation. Furthermore, the structure is simplified as there is no need for positioning devices such as stoppers. Furthermore, since the position of the set and positioned end face of the steel pipe remains constant, stable cutting conditions can be obtained, and there is no need to estimate wasteful cutting allowance, making it possible to shorten cutting time. In addition, the setup work does not require work such as adjusting the loading position of the steel pipes, so even inexperienced workers can easily perform the work.

Further, according to the present invention, the length of the steel pipe is not limited and can be freely adjusted.

As described above, the present invention is not limited to the configurations shown in the embodiments, and modifications are expected without departing from the technical idea of the present invention as described in the claims.

[Brief explanation of the drawing]

Fig. 1 is an overall view of a steel pipe feeding device installed in a steel pipe end face processing machine, Fig. 2 is a sectional view taken along line A-A in Fig. 1, and Fig. 3 is a steel pipe positioning control device for carrying out the present invention. FIG. 4 is a speed diagram of steel pipe feeding, and FIG. 5 is a comparative explanatory diagram showing set lengths with respect to steel pipe diameters. In the figure, 1... base, 2... steel pipe, 6...
Feeding table, 7... Servo motor, 9... Grasping device,
16...processing machine, 19...main axis, 23...emitter, 24...light receiver, 28...linear scale.

Claims (1)

[Claims] 1. In a machine that transports a long work along the spindle axis and processes the end face of the long work, there is a base provided at a position where the work is fed, and a machine that is movably provided on the base in parallel to the spindle axis. a feeding table, a driving device for driving the feeding table, a gripping device provided on the feeding table for gripping a work carried in on the spindle axis, and a movable block forming a workpiece gripping surface of the gripping device. a first detection means for detecting an opening/closing amount; a second detection means for detecting a workpiece end surface that is arranged between the feed table and the rear of the workpiece end surface processing machine and fed by the feed table; A third device that continuously detects the forward and backward movement position of the feed base.
a detection means for storing the distance from the position of the second detection means to the machining position of the end face of the workpiece as the workpiece transfer amount for each diameter; It consists of a calculation processing means that compares the value with the value of the detection means, and a control means that changes the feed speed according to the transfer amount in the calculation process of the calculation processing means, and automatically changes the transfer amount of the workpiece according to the diameter of the workpiece. A workpiece positioning device for a long workpiece processing machine, which is characterized by changing the position of the workpiece.