JPS5849447B2 - Bar positioning device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a center positioning device for positioning a dog-shaped round bar work whose length varies to the correct center position of a processing machine.

For example, for artificial graphite electrodes for electric steelmaking furnaces, after the primary fired product is taken out of the furnace, it must be fed to an electrode polisher and placed at an accurate processing center position.

Generally, the electrode material, ie, the center of the workpiece, is fed so as to match the processing center of the processing machine, and in the past, various methods have been devised and implemented for this purpose.

The object of the present invention is to provide a means for center positioning a workpiece that is considerably heavy and whose length fluctuates using the simplest and most robust device, without requiring high positional accuracy such as the positioning of precision parts.

In such cases, the conventional method is to place the workpiece transported by a crane or conveyor into the processing position of the processing machine, and then move it to the correct position by hand or with an attached positioning device. It is.

There is also a method in which the workpiece is not placed directly into the processing machine, but is parked on the side of the processing machine, the position is adjusted here, and then the workpiece is placed in the processing position.

In a device similar to this invention, a workpiece is sent to the side of a processing machine by a conveyor, and when the same number of detection switches in front and rear of the center of a large number of detection switches arranged symmetrically forward and backward from the center of a required stopping position output a detection signal, One possibility is to stop the workpiece, move it to the side, and put it into the processing machine.

If the workpiece is a carbon electrode, this level of accuracy is fine, but in practice, the detection switch frequently breaks down, causing problems in operation, and has the drawback of high repair costs.

This invention uses multiple detection switches to accurately align the center point of the workpiece with the center of the required stopping position on the conveyor and stop the workpiece, and also to move the stopped workpiece horizontally to the correct position on the processing machine without any deviation. It is.

First, the principle of this invention will be explained with reference to FIG.

From the right to the left of the work W paper diagram, the transport device, in this case,
It is conveyed by a roller conveyor 1.

On the conveyance path, a workpiece positioning and stopping center point M corresponding to the center of the processing position of the processing machine is assumed.

A detection switch S is placed at a fixed point A, which is a distance a from this stop center point M, and is activated by detecting the front end of the workpiece being transported, and is deactivated when the rear end of the workpiece is reached.

When this switch S is activated, the timer T starts counting, but the timer T can change the timekeeping speed to two slow speeds, and when the switch S is activated, the timer circuit is switched and the timer T starts counting at a relatively slow speed. Start.

When the operation of the switch S is canceled as the rear end of the workpiece W passes point A, the previously switched timer circuit returns.
Thereafter, time measurement is continued at the doubled time measurement speed, and when the set time count is reached, the timer T issues a command to stop the workpiece W using a well-known control circuit.

That is, in the figure, the conveying power source P is commanded to stop the conveying device, but a mechanism that only stops the workpiece W without stopping the conveying device may be used.

The time count set in advance in the timer T is a value obtained by dividing the distance a by the workpiece conveyance speed, or a multiple thereof.

Although the details will be described later, the timer T is calibrated to indicate the time when the charging circuit is only connected to R.

The variable resistor R' is also set to have the same characteristics as R and has the same scale.

With this, even if the number of detection switches S is small, the workpiece W will stop the moment the center of the workpiece W accurately reaches the positioning stop center point M.

The reason for this will be explained below. Distance a from stop center point M to fixed point A where detection switch S is located and length 1 of workpiece W
is expressed in meters, conveyance speed is expressed in (m/sec),
Let us express in seconds the elapsed time t1 when the leading edge of the workpiece W advances by its own length 1 after passing point A, and the time t2 until the workpiece center reaches the stop position at point M.

The timing speed of the timer T is relatively slow and counts 1 in 2 seconds while the detection switch S is detecting from the front end to the rear end of the workpiece.

After that, the clock will count 1 every second.

Therefore, the time required for the leading end of the workpiece to reach the correct stop position C from point A is (t1+t2) seconds, but timer T measures this time as (t/2+t2).

l By the way? By setting the count of timer T to (a/v), a stop command will be issued when the tip of workpiece W reaches the required point C, which is (a + 1/2) from point A. It will become.

Also, the timing speed of timer T is initially set to 1 per second,
It may be set to 2 in 1 second after switching.

In that case, it actually takes (t+12) seconds or S, but (t
+2t2), but since it is 1, it is only necessary to set the count of the timer T to (2 a / v).

Since both (a/■) and (2a/v) are constants that are unrelated to the workpiece length 1, the center of the workpiece W always stops at the positioning center point M without any problem even if the workpiece length changes.

Steps 4 and 5 are used to switch the timing speed of timer T in two stages.
You can create a circuit like the one shown in the figure.

In FIG. 4, a variable resistor R' is inserted in series with the CR charging circuit of a CR type timer.

Then, set the resistance value to be the same as the resistance R inside the timer.

Furthermore, if the b contact sb of the detection switch S is connected in parallel with this variable resistor R' and in series with the CR charging circuit, the timer will work at a timekeeping speed of 1/2 second while the switch S is operating, and will work at a timekeeping speed of 1/1 second after switching. becomes.

Note that the timer starting circuit is omitted in the figure.

In FIG. 5, a variable resistor R' is inserted in parallel with the resistor R of the CR charging circuit to match the resistance value inside the timer.

When the b contact sb of the detection switch S is connected in series (parallel to the resistor R) to the variable resistor R', the timer operates at a timing speed of 1/1 second at first and at 2/1 second after switching.

To explain the operation of the timer in Fig. 4, the detection switch S
When T is off, its b contact sb is closed and timer T operates as a normal timer.

When the detection switch S is turned on, the resistance value of the CR charging circuit doubles, so the timer's timing speed becomes 1/2 of the normal state.
be late.

The theoretical explanation will be omitted.

The explanation of the one in FIG. 5 is also omitted because it is similar.

Now, Figures 1 and 2 show a carbon electrode material positioning device that uses a rod-shaped carbon electrode material used in electric steelmaking furnaces, etc. as a workpiece, and accurately feeds this workpiece, which varies in length, to the processing center position of an electrode polishing machine. This is an example to which this invention is applied.

The electrode material which is the work in this case is assumed to be W.

The conveyance device is a roller conveyor with rollers 1 lined up.
Lay the workpiece along the center line of the conveyor and send it to the front of the processing position.

Parallel rails 2 that are perpendicular to the direction of movement and that are sunk below the roller surface during normal times are inserted between the par rollers 1 at the electrode material stop position.
One end of this parallel rail 2 reaches a processing position within the electrode polishing machine 3, and the other end holds and supports an electrode pushing device 4.

In addition, a lifting device, in this case a hydraulic cylinder 5, is provided below to unite all of the rails 2 and push the upper surface upwards from the surface of the roller 1, and by its operation, the parallel rails 2 are moved to the support provided at the front of the electrode polishing machine 3. It rotates around its axis and moves up and down.

The solid line position of the parallel rail 2 in FIG. 1 indicates when it is rising, and the chain line position indicates when it is descending.

The electrode pushing device 4 moves up and down together with the rail 2.

Each roller 1 of the roller conveyor is driven by a chain by an electric reducer 7, but the common chain 8 is hung downward so as not to interfere with the vertical movement of the parallel rail 2 sunk between the rollers. Each roller 1 is driven by.

The parallel rail 2 is oriented perpendicularly to the longitudinal direction of the electrode material at the processing position of the electrode polisher 3, and the roller conveyor is perpendicular to the parallel rail 2.

The point where the center line of the electrode material at the processing position intersects the axis of the conveyor becomes M, which is the center point for positioning and stopping the electrode material on the conveyor.

A detection switch, in this case a limit switch S, is provided at a fixed point A on the conveyor a distance a from point M.

The center line of the electrode pushing device 4 also passes through point M toward the electrode polisher 3.

When the tip of the electrode material W carried on the roller conveyor passes over the detection switch S, the attached timer starts timing at a relatively slow speed as described above.

When the rear end passes, the charging circuit of the timer is switched and the clocking speed is doubled, and when the set clocking speed of (a/V) described above is reached, the timer T issues a command to stop the conveyor.

As a result, the center point of the electrode material W comes to a stop coincident with point M, which is located directly in front of the processing position stop point.

Subsequently, when the hydraulic device 5 operates to push the parallel rail 2 up to the horizontal position or to the position shown by the solid line in FIG.

Then, the fluid pressure cylinder 4a of the electrode pushing device 4 works to push out the wide pushing frame 4c, which rests on both front and rear wheels running along both outer rail sides, and the pushing head 4d on the front side thereof.

Since the pushing heads 4d are aligned at appropriate intervals, the electrode material W
Even if the electrode is not a perfect cylinder, it is reliably moved in parallel on the rail 2 in the perpendicular direction and sent to the processing position of the electrode polisher 3.

The front surface of the pushing head 4d is slightly tilted upward, which is effective for pushing up and rolling heavy electrode materials.

The cylinder 4a is attached to both outer rails, and the push frame 4
Since c always runs along the rail 2, it is also possible to stop the rail 2 before it becomes horizontal and push the electrode material W up a little N to prevent the electrode material W from moving freely.

Although one embodiment has been described above, it goes without saying that this invention can be varied and applied in various ways depending on the designer.

This invention transports the workpiece to the side of the processing machine using a conveyor,
A number of detection switches and a timer are used to stop the workpiece the moment the center of the workpiece reaches the positioning stop center point on the conveyance path corresponding to the center of the processing position.Then, the workpiece is moved at right angles and placed in the processing position, unlike conventional transport. It can be easily carried out using equipment, has few failure points, and has an optimal configuration for fully automating the processing positioning of graphite electrodes, which can easily stain the worker's body and equipment.

Even if you stop the work accurately on the conveyance path, it is meaningless if true parallel movement cannot occur during perpendicular transfer, but if the conveyance path is a roller conveyor, parallel rails sunk between the rollers rise to receive the work, and the rails Since the heavy workpiece is accurately translated in parallel by the pushing device that is engaged and supported by itself, the positioning accuracy on the conveyance path is directly transferred to the processing position.

[Brief explanation of drawings]

Fig. 1 is a front view of an embodiment of the present invention, Fig. 2 is a plan view thereof, Fig. 3 is an explanatory diagram of the principle, and Figs. 4 and 5 are explanatory diagrams of a timer. 2 is parallel rail, 3
is an electrode polisher, 4 is an electrode pushing device, 5 is a rail lifting device,
M is the positioning stop center point, A is the fixed point, and S is the detection switch.

Claims (1)

[Scope of Claims] 1. A roller conveyor that feeds dog-shaped nine-bar materials by laying them along the conveyor center line, and parallel rails that are perpendicular to the conveyor in front of the processing position and have each end of the rail reach the processing position; The rail end side of this parallel rail is pivotally supported, and the other lower end side is raised and lowered, and when the above-mentioned bar comes, the upper surface of each rail is raised from between the conveyor rollers, and the bar is placed horizontally or just before it. a rail lifting device that stops at a certain position; a wide bar pushing frame that runs on both outer rails of the parallel rail; a pushing frame driving device attached to the other end of the parallel rail; During the passage, there is a detection switch that operates, and the switch starts timing, and even after the operation ends, the clocking speed is halved or doubled to continue counting, and when the clock reaches the set value, the bar is stopped. Timing speed switching type C set so that the center point of the bar is directly in front of the center point of the processing position
A bar positioning device comprising: an R-type timer. 2. In the bar positioning device according to claim 1, the time measuring speed switching type CR timer is configured such that the C in the timer
A variable resistor R' equal to the resistance R is added in series to the R charging circuit, and a b contact connected in parallel to the variable resistor R' and in series with the CR charging circuit is opened and closed by the detection switch. thing. 3. In the bar positioning device according to claim 1, the time measuring speed switching type CR timer includes a variable resistor R' equal to the resistance R of the CR charging circuit in the timer, which is added in parallel to the resistor R together with a b contact. , the b contact connected in series with the variable resistor R' is opened and closed by the detection switch.