JPH0332408B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a billet transfer device for a press machine in which misclamping and missetting of billets can be accurately detected by simple means.

In billet forging, the most frequently used means for transferring the billet to the mold of the press machine is a clamp arm that moves the billet forward and backward and up and down using the required movement mechanism. The billet is clamped by a pair of clamp claws that can be opened and closed, and the billet is conveyed to the press mold, and when the grip is released, the billet falls into the mold. When the billet is clamped and the required carrying movement is carried out, there is a failure in clamping, that is, an incorrect clamp, and furthermore, when the clamp is released on the mold and the billet is allowed to fall, the billet is not set correctly and the billet is not properly set. If the top of the mold lands on an inclined surface or rolls, that is, if it is misset, this should be detected immediately and the press machine operation should be stopped immediately to prevent damage to the press side or transfer device side. is necessary. Conventionally, it is known that there are various types of abnormality detection devices for mis-clamping and mis-setting. , methods using proximity switches are known, but all of them have complicated mounting and installation structures, tend to be large and heavy, and phototubes, etc. are often used as misset detection means. However, because the space between the transfer device, punch, and billet is extremely narrow, it is difficult to accurately check only the billet, and it is difficult to check the billet at the right time when it falls into the mold. However, many problems still exist, such as difficulty, frequent malfunctions, and failure to obtain satisfactory functional effects.

In order to solve the problems in the conventional detection of misclamps or missets, the present invention has been developed by passing an electric circuit current for detection between the clamp claws held by the clamp arm and directly clamping the billet, and the billet. By comparing the signal generated by a signal generator that rotates in synchronization with the rotational movement of the shaft, misclamping can be immediately detected through the contact and separation of the billet and clamp jaw, and furthermore, it can be detected between the clamp jaw, billet, and mold. By passing a current through the electric circuit for the purpose of the clamp and comparing it with the signal generated by a similar signal generating device, a misset can be immediately detected through the contact between the contact member provided on the clamp claw and the billet, resulting in a compact device. The structure makes it easy to obtain an accurate detection function, and its characteristics include a pair of clamp claws for gripping the billet and a gripping billet as circuit components, and a press crankshaft. A mis-clamp detection circuit is provided, which comprises a signal generating device such as a rotary cam switch that rotates in synchronization with the angle and generates a signal, and a contact opening/closing relay that operates through the contact and separation of the clamp claw and billet. Along with the circuit,
A rotary cam switch, etc. that includes a detection member such as a spring that is provided on a clamp claw and comes into contact with a missetting billet, and the billet and mold as circuit components, and rotates in synchronization with a press crankshaft to generate a signal. The misset detection circuit comprises a signal generator and a contact opening/closing relay which operates through contact between the detection member and the billet.

The present invention will be described in detail below based on the illustrated embodiment. In FIGS. 1, 2, and 3, a target billet 17 is attached to each tip of a pair of openable and closable clamp arms 10, 10 in a known transfer device. The clamping claws 3, 3 are held and fixed together in an electrically insulated state. Since this is a known transfer device, a detailed illustration thereof will be omitted, but since the pair of clamp arms 10, 10 can be opened and closed mutually, the integrated clamp claws 3, 3 can also be opened and closed together to clamp and hold the billet 17. The arms 10, 10 as a whole are given forward, backward, and upward and downward movements by a required movement mechanism, so that the pair of horizontal and parallel clamping claws 3, 3 can move, for example, In the released state, the billet 17 is lowered at the loading point, raised with the billet 17 closed, and then advanced toward the mold.By lowering the billet at the setting point and releasing the clamp at the lowering point, the billet 17 is placed in the mold. When the setting is completed, the robot moves back to the loading point by the reverse process and waits. Failure to grasp the billet 17 during the movement of the clamp claws 3, 3 back and forth, and up and down, is a state of misclamping. Furthermore, FIG. 6 schematically shows a misset state at the setting point in the mold.
That is, if the clamp claws 3, 3 are opened and the unclamped billet 17 descends correctly vertically, it will fall and be properly set in the mold 19. As shown in 17a, the fallen billet 17 tilts or rolls and rolls irregularly on the upper surface of the mold. This is a misset condition. In the case of these misclamps and missets, the operation of the press machine must be stopped. It is necessary to make an emergency stop to prevent damage to the machine and equipment and eliminate the trouble. Since the space for detecting misclamps and missets is extremely narrow, the means for detecting misclamps and missets must be compact in construction and must exhibit prompt and accurate detection functions.

In configuring an electrical detection circuit for detecting such misclamps and missets, the present invention attaches a clamp claw 3 to the tip of a clamp arm 10 via an insulating seal 1, and further attaches an insulating ring 2 to the tip of a clamp arm 10, as shown in the figure. The lead wires 5 and 14 for the mis-clamp detection circuit are connected to each of the clamp claws 3 and 3, and when the clamp claws 3 and 3 are closed to clamp the billet 17,
This allows the circuit current to flow between the clamp claws 3, billet 17 and the clamp claws 3, and if a gap is created between the clamp claws 3, 3 and the billet 17,
The circuit current will now be interrupted. One of the clamp claws 3 is provided with a protrusion 3a at a position eccentric from the clamping center of the billet 17, and a contact member 11 formed by a spring for detecting a misset is provided in a protruding manner through an insulating spacer 12 insulated from the clamp claw 3. This contact member 11 is provided on the billet 1.
When the billet 7 is dropped and set into the mold 19 by releasing the clamp claws 3, 3, the billet 17 is misset and the 6th billet is placed on the upper surface of the mold 19 without any interference during normal vertical drop. It is assumed that contact occurs only when tilting and rolling, as shown by dotted lines as billets 17a in the figure.

The misclamp detection circuit B according to the present invention has a second
As illustrated in the figure, the above-mentioned clamp claws 3, 3
The billet 17 and the clamp claws 3, 3 are interposed in the circuit B, and the power generator 6 and one clamp claw 3 are connected to the circuit B. Connecting lead wire 1
On the 4th side, there is a 360mm press crankshaft (not shown).
The billet 17 rotates 360 degrees in synchronization with the normal clamping claws 3, 3, and a signal generating device 8 that generates a signal is intervened. Although various devices can be used as the signal generator 8, a known rotary cam switch is used in the illustrated example. Although the switch is not shown, it is a contact type in which a disk-shaped switching board with a cam shape is attached to the rotating shaft, and a signal is generated when the peripheral edge of the cam with a large radius contacts the actuator. In this case, the rotating shaft of the switching board is the crankshaft, which rotates 360 degrees (one rotation).
During this time, it also rotates 360 degrees (one rotation). In addition, the power generation section 6 and the other contact member 11
A contact opening/closing relay 9 is interposed in the lead wire 5 connecting the clamp claw 3 equipped with the clamp claw 3, and since the resistance value changes depending on the material of the billet 17 and the material of the clamp claw 3, a voltage regulator 7 is inserted. be. The relay 9 has clamp claw 3 → billet 1
7-> It is operated by the current flowing through the clamp claw 3, for example, using an electromagnetic relay that opens and closes the contacts by electromagnetic force, and has an A contact that closes only when operated, and a B contact that opens only when operated. .

On the other hand, the misset detection circuit C according to the present invention
As also illustrated in FIG. 2, the contact member 1
A relay 16 and a signal generator 15 similar to those described in connection with the misclamp device A, as well as a voltage regulator 18, are inserted into the lead wire 13 connected between the power source generator 1 and the power source generator 6, and a voltage regulator 18 is inserted between the lead wire 13 and the power generator 6. If the billet 17 is not set correctly on the mold 19 and rolls, the billet 17 will contact the contact member 11 and the billet 17 will move from the contact member 11 to the billet 17.
→The misset is detected by activating the relay 16 by causing a circuit current to flow between the molds 19 (which are grounded). The relays 9 and 16 in both circuits B and C described above are connected to the emergency stop signal device and the alarm signal device (not shown) on the D side, thereby detecting misclamps and missets. At the same time, the press is brought to an emergency stop and the necessary alarm notification is issued.
FIG. 7 schematically shows the contact state between the contact member 11 and the tilted and rolled billet 17a in the misset state described above.

According to the transfer device of the present invention, by providing both the misclamp detection circuit B and the misset detection circuit C on the side of the pair of clamp claws 3, 3 and the contact member 11 that directly clamp the billet 17, it is possible to prevent mistakes. Detection of clamps and missets is properly performed as follows.

That is, FIG. 4A to F show the detection contents of misclamp by the misclamp detection circuit B, and FIG. The OFF part of the figure shows the state of the signal when it is clamped (using the b contact of relay 9). On the other hand, what is shown in Figure B is the monitoring range for misclamping that is set in accordance with the press crankshaft angle in the signal generator 8 that rotates in synchronization with the press crankshaft, and the ON part in the diagram corresponds to this. Yes (using the a contact of relay 9). Therefore, if the billet 17 is dropped by the clamp pawl 3 during transportation, the signal from the pawl will be
Compared to Figure A, the OFF part changes as shown in Figure 4 C, so relay 9 is activated to detect the misclamp as shown in Figure 4 D, and the emergency stop signal device is activated. Then, the alarm signal device D side is activated to stop the machine and prevent damage. Furthermore, if the billet 17 is dropped from the claw 3 at the start of billet conveyance, the OFF portion of the signal from the claw changes as shown in Fig. 4E, compared to Fig. 4B, and as a result, as shown in Fig. 4F. Misclamping is detected in this way, and the machine is stopped and damage is prevented in the same way.

Fig. 5 shows the misset detection by the misset detection circuit C, in which the billet 17 held by the clamp claws 3, 3 is released from the mold at the falling set point by the clamp claws 3, 3. 19 and there is no missetting, the contact member 11 in circuit C does not come into contact with billet 17 at all, so the signal from member 11 remains constant throughout the entire stroke, as shown in Figure 5A.
Figure 5 (b) shows the misset monitoring range set corresponding to the crank angle in the signal generator 15 that rotates in synchronization with the press crankshaft. Using the b contact at 16, and b is a
Using contacts is the misclamp detection circuit B.
It is similar to that in . Therefore, as shown in FIGS. 6 and 7, especially in FIG. 7, when the billet 17 is misset as shown in 17a and the billet 17 comes into contact with the contact member 11, the contact member 11 billet 17a mold 17 (grounded), by the current flowing between
As shown in the ON part of the signal from the contact member 11 in the case of a misset shown in FIG. 5C, and the ON part of the misset detection shown in FIG. By activating the signal device and alarm signal device D, operation can be stopped and damage can be prevented.

According to the present invention, compared to various misclamp and misset detection means provided in conventional transfer devices, the clamping claws 3, 3 that directly clamp the billet 17 are used as circuit components, and the clamping Mis-clamping of the billet 17 can be detected by passing a current in the detection circuit between the billet jaws 3 and the clamping jaws 3, outputting a signal corresponding to the press crank angle from the signal generator 8 which rotates in synchronization with the press crankshaft, and comparing it. Accurate detection is possible, and a quick response can be easily obtained throughout the entire series of billet loading operations from the loading position of the billet 17 to the dropping set position, without fear of malfunction, and high detection is possible with a simple circuit configuration. It is superior in that it provides high precision and requires an extremely compact structure. Furthermore, when the billet 17 is dropped into the mold and set, a contact member 11 that can come into contact with the billet by missetting the billet is attached to a part of the clamp claw 3, and the contact member 11, the billet 17, and the metal are attached to a part of the clamp claw 3. By comparing the misset detection circuit C, which uses the mold 19 as a circuit component, with the signal output from the similar signal generator 15 corresponding to the press crankshaft angle, the misset can be similarly accurately detected. According to this, a misset billet can be reliably detected regardless of the position of the transfer device or punch, and the presence or absence of a misset can be known in accurate synchronization with the timing of the billet falling into the mold, thereby preventing mistakes. Like the clamp detection circuit B, the circuit C can be simple and compact, and troubles caused by misclamping and missetting in this type of press can be quickly dealt with.

[Brief explanation of drawings]

Fig. 1 is a front view of an embodiment of the main part of the device of the present invention;
The figures are a view taken along the line A-A in Fig. 1, Fig. 3 is an explanatory diagram of an embodiment of the same misclamp and misset detection circuit, Fig. 4 is an explanatory diagram of the misclamp detection state, and Fig. 5 is an explanatory diagram of the same misset detection state. FIG. 6 is a schematic diagram of the main parts of a conventional billet, clamp claw, and mold set, and FIG. 7 is a schematic diagram of the main parts of the present invention. 1... Insulating seal, 2... Insulating ring, 3...
Clamp claw, 5, 13, 14...Lead wire, 6...
...Power generation section, 7, 18...Voltage adjustment section, 8, 1
5... Signal generator, 9, 16... Relay, 10
...Clamp arm, 11...Contact member, 17...
... Billet, 19... Mold, B... Misclamp detection circuit, C... Misset detection circuit.

Claims (1)

[Claims] 1. In a transfer device that grips a billet by a pair of parallel clamp claws that are held by a clamp arm and are movable up and down, and that can be opened and closed, and transports and drops the billet into a press mold, the pair of clamps A signal generating device such as a rotary cam switch that includes a claw and a gripping billet as circuit components and rotates in synchronization with the press crankshaft to generate a signal, and a contact opening/closing relay that operates through the contact and separation of the clamping claw and billet. A billet misclamp detection circuit is provided, which includes a detecting member such as a spring provided on the clamp claw and comes into contact with the missetting billet, and the billet and mold as circuit components, and is synchronized with the press crankshaft. A billet misset detection circuit comprising a signal generating device such as a rotary cam switch that rotates to generate a signal, and a contact opening/closing relay that operates through contact between the detection member and the billet is provided. Press transfer device.