JPH0479956B2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention moves an actuator by the rotation of a sheave suspended by suspension means such as a wire rope, metal tape, or chain, and grips the actuator by the rotation of the sheave. The present invention relates to a claw opening/closing device for a gripping tool that operates a claw.

The claw opening/closing device of the present invention can be particularly preferably applied to gripping tools used in fuel handling machines such as fuel exchange machines, fuel loading/unloading machines, and cask cars in nuclear reactor facilities.
It can also be applied to general industrial gripping tools that grip objects by operating gripping claws.

<Prior Art> A gripping tool of a fuel handling machine used for loading or unloading a nuclear fuel assembly (hereinafter referred to as "fuel") in a fast breeder reactor core will be described below as an example.

As shown in Figure 3, a handling head part 2 is provided on the top of the fuel, in which a grip part 1 that fits with the claws of a gripper is machined, while a gripper 3 has a handle inside thereof. A sheave 5 rotated by a windable suspension means 4 such as a wire rope, metal tape, or chain, an actuator 6 rotatably suspended at a position eccentric from the center of rotation of the sheave, and a convex portion 6a at the free end of the actuator.
The claw body 7 opens and closes by lever action due to the vertical movement of the
is incorporated. The operation of such a gripping tool 3 is as follows.
This is carried out by a gripper drive device 8 provided above, and a pair of winding drums 9a and 9b for winding up or lowering the suspension means 4 are housed inside. That is, by simultaneously winding up and lowering the suspension means, for example, the metal tapes 4a and 4b, by the drums 9a and 9b, the entire gripping tool 3 can be raised and lowered as it is or with fuel gripped. Furthermore, by lowering the tape 4a from one drum 9a and winding up the tape 4b for the same stroke on the other drum 9b, it is possible to rotate only the internal sheave 5 while keeping the position of the gripping tool 3 unchanged. The rotary movement of the sheave is controlled by actuator 6.
is converted into a vertical movement of the convex portion 6 of the actuator.
The claw body 7 swings about the pin 10 as a fulcrum and opens and closes due to the vertical movement of a.

<Problems to be Solved by the Invention> However, regarding the drive for opening and closing the claws of the conventional gripping tool described above, a complicated mechanism is used in the gripping tool drive device to avoid interference with the transmission system for raising and lowering the entire gripping tool. However, in order to open and close the claw, it is necessary to rotate a pair of winding drums using a motor, and to wind down the same stroke of metal tape with one drum and wind it up with the other drum. Therefore, () the opening/closing operation of the claw and its confirmation must be performed by calculating the stroke of a suspension means such as a metal tape, which requires a complicated measurement/control circuit.

() Since the two axes for opening and closing the claws must be driven synchronously by one or two drive devices, it is necessary to use multiple gears, clutches, brakes, etc., and therefore the reliability of operation is low. .

() From the above () and (), the claw opening/closing device ends up being expensive and structurally complex, requiring a large space.

There were some drawbacks.

Therefore, the present invention improves the drawbacks of the prior art as described above, and provides a claw opening/closing device for a gripping tool that has a simple structure, can be made compact, and can operate with high certainty and reliability. It was made for the purpose of providing.

<Means for Solving the Problems> The present invention provides a conventional gripper as shown in FIG. A gripping tool in which one end of an actuator is rotatably suspended, the free end of the actuator is brought into sliding contact with a claw body, and the claw body is opened and closed by vertical movement of the actuator due to rotation of the sheave. Thus, a claw opening/closing device for a gripping tool is provided in which the claw body is opened and closed.

The claw opening/closing device according to the present invention has a pair of winding drums for winding up or lowering the suspension means above the gripper. Each of the drums has a through hole in its center, and a spiral groove is cut into the inner surface of the through hole. Each such through hole includes
A helical spline shaft having teeth that mesh with a helical groove cut into the inner surface is slidably inserted therethrough.
These pair of helical spline shafts are arranged parallel to each other and have the same shape and tooth profile in the same torsional direction. In addition, one end of the pair of helical spline shafts on the same side is connected to one table via a joint that does not transmit the rotation of the helical spline shaft but transmits reciprocating motion in the axial direction, while the other end is connected to the helical spline shaft. The spline shaft is supported by a support means that does not allow rotation but allows reciprocating movement in the axial direction. Furthermore, each of the drums is provided with a frame means that does not allow axial movement but only rotation.

With the claw opening/closing device having the above structure, the pair of winding drums are rotated simultaneously and in the same direction by the reciprocating movement of the table, and the suspension means is hoisted up or down in the same stroke to open the claw opening/closing sheave. It can be rotated.

<Examples> The present invention will be described in further detail below with reference to preferred embodiments shown in the drawings.

FIG. 1 is a perspective view showing a preferred embodiment of the pawl opening/closing device of the present invention, in which a sheave 5 rotates by a windable suspension means 4 such as a chain, and a sheave rotatable to a position eccentric from the sheave rotation center. The depending actuator 6 is similar to that in the conventional gripper 3 of FIG. Further, the pair of winding drums 19a, 19b in FIG. 1 have substantially the same function as the conventional winding drums 9a, 9b in FIG. .

The winding drum 19a has a cylindrical portion 11 that projects from both sides and is integral with the drum, and a through hole 12 provided at the center of the drum extends into the cylindrical portion 11. The inner surface of this through hole 12 has a helical groove 13 that meshes with the tooth profile of a helical spline shaft 17a, which will be described later.
is dug out. This drum 19a has a cylindrical portion 1
1, the drum 19a is supported and fixed by a frame means 16 consisting of a bearing 14 and a fixed frame 15, so that the drum 19a rotates but is supported so that its movement in the direction of the rotation axis is restricted.

A helical spline shaft 17a having teeth that mesh with a spiral groove 13 carved on the inner surface of the drum 19a is inserted into the through hole 12 of the drum 19a so that it can slide with the spiral groove and teeth meshing. One end of this helical spline shaft 17a is connected to a table 20 via a joint 18. FIG. 2 shows a detailed view of this connection part, in which the cylindrical end formed at the end of the helical spline shaft 17a is connected to the joint 1.
It is rotatably inserted into the through hole 21 of No. 8 and is held by the end plate 22 so as not to come out. On the other hand, joint 1
8 is integrally engaged with the table 20 by a pin 23. With such a connection style, the rotation of the helical spline shaft 17a is controlled by the rotation of the table 20.
The axial reciprocating motion of the table 20 can be transmitted to the helical spline shaft 17a.

On the other hand, the other end of the helical spline shaft 17a is
The helical spline shaft 17a is supported by a support means 30 that does not allow rotation but allows reciprocating motion in the axial direction. In the embodiment shown in FIG. 1, this support means 30 is composed of a gear 31 integrally attached to the end of the helical spline shaft 17a, and a cylindrical coupling 32 into which this gear fits. , the gear 3 is on the inner surface of the coupling ring 32.
A straight spline 33 that meshes with 1 is carved. If this support means 30 is fixed so as not to rotate, reciprocating motion of the helical spline shaft 17a in the axial direction becomes possible by sliding the gear 31 and the straight pline 33 while being meshed with each other. The helical spline shaft 17a integrally connected thereto does not rotate.

In the above description, the drum 19a, the helical spline shaft 17a, and the structures associated therewith have been described, but the drum 19b, the helical spline shaft 17b, and the structures associated therewith, which are paired with these, are also completely similar, so to avoid duplication, The explanation will be omitted. What should be particularly noted here is that the pair of helical spline shafts 17a and 17b are arranged parallel to each other, and that the tooth profiles of the helical splines have the same shape and twist direction.

In the illustrated embodiment, the shaft 34 is further extended from the coupling ring 32, and the gear 3 is attached to the tip of the shaft 34.
5a is attached so that the rotation of this gear 35a is transmitted to the coupling ring 32. On the other hand, a gear 35b is similarly attached to the side of the helical spline shaft 17b, and the gears 35a and 35b are meshed with each other and connected.

Next, the operation of the pawl opening/closing device constructed as above will be explained. When the table 20 is moved in the direction of the arrow in the figure, the movement is transmitted to the helical spline shafts 17a, 17b via the joint 18, and the table 20 moves to the left in the figure. At this time, if the support means 30 is fixed so as not to rotate, the helical spline shaft 17a,
17b does not rotate but moves in the axial direction. As a result, the drum 19a, which is rotated by the frame means 16 but not moved in the axial direction,
Due to the sliding action between the helical groove 13 and the helical spline of the helical spline shaft 17a, which are slidably engaged, the table 20 rotates in the direction of the arrow by an amount proportional to the amount of movement, and the drum 19b similarly rotates by the same amount. Rotate in the same direction. Then, drum 19
Chain 4a that engages with the circumference of a without slipping
is hoisted up, and the chain 4b, which engages with the drum 19b, is hoisted down. As a result, the sheave 5 can rotate in the direction of the arrow without changing its vertical position, and the actuator 6 can be pulled up by the required stroke. On the other hand, if the table 20 is moved in the direction opposite to the direction of the arrow in the figure, the actuator 6 can be lowered by a stroke proportional to the amount of movement. The reciprocating motion of the table 20 in the axial direction can be provided by an existing power cylinder (not shown) or the like.

The entire gripping tool can be raised and lowered using the apparatus of the illustrated embodiment as follows. Connected gears 35a, 3 are connected by a gripper lifting motor (not shown).
When either gear 5b is rotated in the direction of the dotted arrow, the gears 35a and 35b rotate in opposite directions. This rotation is applied to the helical spline shaft 17a through the coupling 32 and the gear 31 that meshes with the straight spline 33 of this coupling.
However, the rotation of these 17a and 17b is not transmitted to the table 20 by the joint 18. Furthermore, even if forces in opposite directions in the axial direction are applied to the table 20 from each of the shafts 17a and 17b, the table 20 is guided so that it can only move in translation in the axial direction. Since the table is designed so that it does not rotate, the table posture remains unchanged. Therefore, the helical spline shafts 17a and 17b rotate in opposite directions without moving in the axial direction. On the other hand, since the helical spline of the helical spline shaft meshes with the spiral groove 13 of the drums 19a, 19b, an axial motion force is generated in the drums 19a, 19b as the helical spline shaft rotates. Since axial movement is suppressed by the frame means 16, only the polarizing rotational force is transmitted. As a result, drums 19a, 19
The chain 4 b rotates in opposite directions as shown by the dotted arrows and engages with these drums.
a and 4b are simultaneously hoisted up or down, making it possible to raise and lower the sheave 5, that is, to raise and lower the entire gripper.

The above explanation and examples have been explained using fuel handling equipment in nuclear reactor facilities as an example, but they are also applicable to general industrial equipment in which the actuator is operated using a suspension means and the pawl is operated thereby. The present invention can also be applied to a claw opening/closing device in a gripping tool.

<Effects of the Invention> Since the pawl opening/closing device according to the present invention has the above-described configuration, it has the following effects compared to conventional devices.

() Reliability of operation is improved because the number of component parts of the pawl opening/closing device is reduced.

() Unlike a clutch, there is no friction transmission means, and two axes can be directly driven in synchronization, improving reliability of operation.

() Since the number of component parts is small, the claw opening/closing device is smaller.

() Since the motion of the motive force for opening and closing the claw is a reciprocating motion, an operation confirmation limit switch can be used, which has the advantages of being inexpensive and highly reliable.

() Since a hydraulic cylinder can be used as the driving force,
It becomes easy to change the opening/closing speed of the claws.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway perspective view showing a preferred embodiment of the claw opening/closing device of the present invention, and Fig. 2 is a -
A partial side view seen from the line direction and FIG. 3 are explanatory diagrams showing a conventional gripping tool and its driving device. 4... Suspension means, 5... Claw opening/closing sheave, 6...
... Actuator, 12 ... Through hole, 13 ... Spiral groove, 16 ... Frame means, 17a, 17b ... Helical spline shaft, 18 ... Joint, 19a, 19
b... Winding drum, 20... Table, 30...
... means of support.

Claims (1)

[Claims] 1 One end of the actuator is rotatably suspended at a position eccentric from the rotation center of the pawl opening/closing sheave rotated by a retractable suspension means, and the free end of the actuator is brought into sliding contact with the pawl body, and the sheave is A pawl opening/closing device for a gripping tool in which the pawls are opened and closed by vertical movement of an actuator due to rotation, the pawl opening/closing device for a gripping tool having a pair of winding devices for winding up or lowering the suspension means above the gripping tool. Drums are provided, each of the drums having a through hole at its center, and a helical spline shaft having a tooth profile that engages with a spiral groove carved on the inner surface of the through hole is slidably inserted into each of the through holes. The pair of helical spline shafts are arranged parallel to each other and have tooth profiles of the same shape and the same torsional direction, and one end of the pair of helical spline shafts on the same side is connected to the helical spline shaft. They are connected to one table through a joint that does not transmit rotation but transmits reciprocating motion in the axial direction, while the other ends of the pair of helical spline shafts do not allow rotation of the helical spline shafts but transmit reciprocating motion in the axial direction. Each drum is supported by support means that allow rotation, and each drum has a frame means that does not allow axial movement but only rotation, so that reciprocating movement of the table also supports the winding of the pair of drums. 1. A pawl opening/closing device for a gripping tool, characterized in that the drums are rotated simultaneously and in the same direction, and the suspension means is lowered or lowered by the same stroke to rotate the pawl opening/closing sheave.