JPH0571333B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the tongs of a four-jaw manipulator.

[Prior Art] As shown in Figs. 12 and 13, conventional tongs are made by attaching jaws e and f having V-shaped recesses c and d to the tips of two links a and b that open and close. It grips the ingot and rotates it while forging the steel ingot.

However, since the opening and closing directions of the links a and b are on a straight line L, the steel ingot g having a square cross section can be reliably clamped by the V-shaped recesses c and d as shown in FIG. As shown in the figure, a steel ingot h with a rectangular cross section and a long length l has a V-shaped recess c,
It cannot be clamped at the corner of d, but must be clamped between the slopes i and j of the V-shaped recesses c and d.

Therefore, when forging a steel ingot h having a rectangular cross section with a hammer or the like, when hitting the narrow side i, it is supported by the recesses c and d, but when hitting the wide side n, the steel ingot h and the recess c , d were easily slippery, and the position of the steel ingot shifted, making it impossible to perform smooth forging work.

[Problems to be Solved by the Invention] The present invention attempts to make it possible to reliably clamp an object such as a steel ingot with a rectangular cross section, which could not be reliably clamped with a conventional two-jaw clamp. It is something.

[Means for Solving the Problems] The present invention provides two pairs of jaws that are arranged in directions orthogonal to each other so that the jaws facing each other with respect to the center of the tongs can open and close symmetrically and synchronously. The tongs of the manipulator are characterized in that they are configured to be able to operate independently.

[Function] Since four jaws are provided and the opposing jaws are opened and closed symmetrically and synchronously with respect to the center of the tongs, the object such as a steel ingot to be gripped can be gripped in alignment with the center of the tongs. , two orthogonal pairs of jaws were made to operate independently of each other, so
Even if the cross-sectional shape of the object is rectangular, it can be reliably clamped.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

FIGS. 1 to 5 show an embodiment of the present invention,
A bracket 2 provided on the hollow shaft 1 for the tongs of the manipulator has links 3, 4 bent in a dogleg shape.
5 and 6 are pivotally connected vertically and horizontally at their base ends with pins 7 so as to be point symmetrical, and each link 3, 4,
Attach the jaws 8, 9, 10, 11 to the tips of the links 5, 6 with pins 12, respectively, and connect the links 3, 4,
Brackets 13 are provided on the outside of the bent portions 5 and 6, and the tips of piston rods 15 made of silicone 14 disposed around the outer periphery of the hollow shaft 1 are connected to each bracket 13 with pins 16, and the links are formed by the operation of each cylinder 14. 3, 4, 5, and 6 can be rotated around a pin 7.

Gear teeth 17, 18, 19, 20 are carved on the outer periphery of the base end of each of the links 3, 4, 5, 6, and the gear teeth 17, 18 of the upper and lower links 3, 4 are
A connecting member 23 having racks 21 and 22 on the upper and lower sides that can engage with the connecting members 7 and 18 is attached, and the connecting member 2
3 is slidably supported by a guide 24 provided within the hollow shaft 1.

Further, another connecting member 25 is arranged so as to intersect with the connecting member 23 at right angles and to be movable separately, and racks 26 and 27 provided on the left and right sides of the connecting member 25 are connected to the left and right sides, respectively. The connecting member 25 is supported by a guide so that it can slide while meshing with the gear teeth 19 and 20 of the links 5 and 6.

Here, the assembly of the connecting members 23 and 25 is as follows:
A window or cutout 28 is provided in the body of one of the connecting members 23.
is provided, and a rack 2 is provided on the member passing through the notch 28.
6 and 27 from both sides, and connect the other connecting member 2.
This is done by setting it to 5.

FIG. 6 shows a hydraulic circuit for supplying pressure oil to each cylinder 14 to operate it. Oil in a tank 31 is discharged to a suction pipe 33 by a pump 32, and a solenoid switching valve is connected to the pipe 33. 34 is provided, and a conduit 36 having a flow rate control valve 35 is connected to the secondary side of the solenoid switching valve 34.
The end of the pipe is branched into four pipes, and each branch pipe 37, 38,
39, 40 to each cylinder 14a, 14b, 14
c, connect to the cylinder head side of 14d. Flow control valves 41, 42, 43 are provided on the piston rod side of each cylinder 14a, 14b, 14c, 14d.
The conduits 45, 46, 47, 48 each having a husband and wife 44 are glued together, and a conduit 49 in which the conduits 45, 46, 47, 48 are merged is connected to the secondary side of the solenoid switching valve 34. In the figure, 50 is a return pipe, 51
indicates an accumulator.

With the above configuration, when clamping a steel ingot with a rectangular cross section, the solenoid switching valve 34 is switched to the state A in FIG.
Pressure oil is supplied to pipes 33, 49 and 45, 46, 4 by
7, 48 to each cylinder 14a, 14b, 14
When it is supplied to the piston rod side of c, 14d, each piston rod is retracted, and the links 3, 4,
5 and 6 open.

Next, attach one end of the steel ingot to each link 3, 4, 5, 6.
After inserting the solenoid valve 34 into the B side, each cylinder 14a, 14b, 14
Pressure oil is supplied to the cylinder head side of cylinders 3 and 14d, and each piston rod is protruded and each link 3,
4, 5, 6 are closed. Each link 3, 4, 5,
6 has its gear teeth 17, 18, 19, 20 meshing with the racks 21, 22 of the connecting member 23 and the racks 26, 27 of the connecting member 25, respectively, so that the upper and lower links 3, 4 and the left and right links 5 , 6 are opened and closed synchronously, but the opening and closing speeds are different from each flow control valve 41, 6.
It is adjusted by the opening degree of 42, 43, and 44.

As shown in FIG. 7, the jaws 8 and 9 of the links 3 and 4 first come into contact with the narrow side of the steel ingot 52 having a rectangular cross section, and the cylinders 14a and 14 push the links 3 and 4.
Although the moving speed of the piston rod b is slow, the links 5 and 6 that clamp the other wide sides are still movable, so the pressure oil supplied from the pipe 36 is mainly sent to the cylinders 14c and 14d. , links 5 and 6 are closed. At this time, if the position of the steel ingot 52 is shifted to the left or right as shown by the two-dot chain line, the jaw 10 of the link 5 on the shifted side will come into contact first, but the link 6 on the other side can be moved. And since they are synchronized by the connecting member 25, when pressure oil is further supplied to the cylinders 14c and 14d, the frictional force between the jaws 8 and 9 and the steel ingot 52 is overcome and the link 5 and the jaw 10 Steel ingot 5
2 is moved to the center of the clamp.

When the steel ingot 52 is moved to the center of the vertical, left and right clamps, the jaws 8, 9, 10, 11 of the four links 3, 4, 5, 6 can come into contact with each side of the steel ingot 52, Further, each cylinder 14a, 14b, 14c, 14d applies a uniform and strong clamping force to each link 3, 4, 5, 6 by the supplied pressure oil.

Therefore, the orthogonal jaws 8, 9, 10, 11 operate independently of each other, and the four jaws 8, 9, 1
The final clamping force is not generated until all 0 and 11 hit the steel ingot.

This makes it possible to reliably clamp a steel ingot with a rectangular cross section.

FIG. 8 shows another embodiment of the present invention, which has a configuration substantially similar to that of the previous embodiment, but uses gear teeth and connecting members with racks as means for synchronizing the upper and lower, left and right links 3, 4, 5, and 6. This is an example in which a connecting member with links is used instead.

That is, a bracket 53 is provided at the base end of the links 3 and 4, and each bracket 53 and a connecting member 54 provided slidably within the hollow shaft 1 are connected to the links 55 and 5.
6 for pin connection and synchronization.

In the case of this embodiment as well, the opening/closing movement of one link 3 is transmitted to the other link 4 via the link 55, the connecting member 54, and the link 56, and they are mutually regulated. It can be gripped at the center of the tongs.

FIGS. 9 to 11 show still another embodiment of the present invention, in which the structure is substantially the same as that of the embodiment described above, and claws 57 and 5 are provided on the distal end surfaces of the respective jaws 8, 9, 10, and 11.
8, 59, 60 to mutually adjacent claws 57, 58,
This is an example in which the parts 59 and 60 are installed so that they can intersect. The width of each claw 57, 58, 59, 60 is made longer than the width of each jaw 8, 9, 10, 11, and the opposing claws 59, 60 are made wider than the other opposing claws 57, 58. It is made to protrude by a thickness of 58 mm.

According to this embodiment, when each link 3, 4, 5, 6 is closed and the distance between each jaw 8, 9, 10, 11 is narrowed, each claw 57, 58, 59, 60 closes a square frame. Since the square claws 57, 58, 59, and 60 cross each other and close, it is possible to reliably clamp a workpiece such as a thin steel ingot that easily escapes or fails to grasp at the center of the tongs.

Note that the tongs of the manipulator of the present invention are not limited to the above-mentioned embodiments; in the embodiments, the operating speed of each cylinder is adjusted by a hydraulic circuit, but there is no such adjustment mechanism. Of course, various modifications can be made without departing from the spirit of the present invention, such as being able to clamp steel ingots having a rectangular cross section.

[Effects of the Invention] As described above, the manipulator and tongs of the present invention are provided with four jaws, and the corresponding jaws open and close symmetrically with respect to the center of the tongs, and the orthogonal jaws operate independently. Therefore, various excellent effects are exhibited, such as being able to reliably clamp steel ingots with a rectangular cross section that could not be clamped with conventional two-jaw tongs.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of an embodiment of the tongs of the present invention;
Fig. 2 is a - direction arrow view of Fig. 1, Fig. 3 is a - direction arrow view of Fig. 2, and Fig. 4 is a - direction arrow view of Fig. 3.
5 is a view taken in the negative direction of FIG. 3, FIG. 6 is a diagram showing a hydraulic circuit for operating the cylinder in FIG. 1, and FIG. 7 is a clamped state of the tongs of the present invention. FIG. 8 is a partial explanatory diagram of another embodiment of the tongs of the present invention; FIG. 9 is an explanatory diagram of still another embodiment of the tongs of the present invention;
0 is a view taken in the - direction arrow of FIG. 9, FIG. 11 is a view showing a closed state of still another embodiment shown in FIG. 9,
Fig. 12 is an explanatory diagram of a conventional two-claw tong, Fig. 13 is a view taken in the - direction arrow of Fig. 12, and
FIG. 4 is an explanatory diagram showing a clamping state using conventional tongs, and FIG. 15 is an explanatory diagram showing another clamping state using conventional tongs. 1 is a hollow shaft, 3 to 6 are links, 8 to 11 are jaws, 14, 14a, 14b, 14c, 14d are cylinders, 17 to 20 are gear teeth, 21, 22, 2
6 and 27 are racks, 23 and 25 are connecting members, 52 is a steel ingot, 54 is a connecting member, and 55 and 56 are links.

Claims (1)

[Claims] 1. Two pairs of jaws that face each other with respect to the center of the tongs can be opened and closed symmetrically and in synchronization with each other. Two pairs of jaws are provided in directions orthogonal to each other, and the orthogonal jaws are configured to be able to operate independently. Manipulator tongs.