JPH057565B2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) During storage, refilling, distribution, and other experiments and processing of radioactive materials, operations can be carried out through the shielding wall of a so-called hot cell, which is surrounded by a protective wall from radioactive contamination. The manipulator (magic hand) that was developed for this purpose has since expanded into a wide range of applications, including the replacement of manual labor, due to the development of robotics technology.

The following discussion regarding improvements in torque actuators suitable as operating parts of such manipulators or similar devices, particularly for accurately guiding minute angular displacements, is placed in the field of robotics technology.

(Prior Art) There are various types of actuators for manipulators installed in the above-mentioned hot cells, but in general, motors, especially electric ones, are unavoidable, so when it is necessary to prevent an explosion, a fluid pressure operated type is preferred. is often used, and in this case it is of course used for general purposes.

However, many of the conventional actuators of this type are of the so-called air cylinder type, but the cylinder-piston assembly is usually made of iron, so the weight of the actuator as an operating part is excessive compared to the operating force. In addition to the disadvantages, it also complicates the conversion transmission system for reciprocating motors, especially in the case of torque actuators that require rotational output.

On the other hand, the air bag type is also known, and in this case, the axial contraction force based on the expansion diameter by applying control pressure to the air bag is used as the operating force for reciprocating displacement, so the air bag itself is lightweight, and the sliding part In addition to having the advantage that it does not contain any frictional force and is virtually free from the influence of frictional force, it is also flexible in itself and is advantageous in that it can generate contractile force even in a curved position.

(Problem to be Solved by the Invention) The advantages of fluid pressure actuators, of which the air bag is a typical example, can be advantageously applied to the operation of torque actuators to easily and accurately output rotation even for minute angular displacements. This paper attempts to propose a simple actuator with a simple structure that can be derived as follows.

(Means for solving the problem) The above purpose can be advantageously fulfilled by a concept based on the following matters.

A rotary cylinder supported by a bearing at the end of the holding rod, an elastic contraction cylinder arranged along the outer periphery of the rotary cylinder over a length corresponding to the circumference, and a concentrically supported cylinder inside the rotary cylinder. , has an output shaft that is transmission-connected to the rotary cylinder through a speed-increasing gear train installed inside the rotary cylinder, and the elastic contraction cylinder has a pair of reinforcing elements made of filaments of organic or inorganic high-tensile fibers arranged in a cross-wound shape. A tubular body of rubber or elastomer-like elastic material with outer circumferential reinforcement braided to fit tightly the embolus inside the tubular body at a position bisecting its total length, and the length of the tubular body relative to the embolus. The center of the tubular body is fixed to the outer periphery of the rotary cylinder, while the ends of the tubular body are closely fitted into respective nipples into the insertions of retaining arms formed overhanging the outer periphery of the rotary cylinder from the above-mentioned retaining rods, and the retaining arms are fitted with both sides of the tubular body. A torque actuator that is constructed by connecting piping that selectively connects each internal part to a pressure control source.

Here, the elastic contractile body can be expressed as follows by applying a control pressure P inside it. Here, P: control pressure d: inner diameter of the tubular body θ: braid angle; subscript 0 is the initial value, and subscript x produces an elastic contractile force according to the angle value at the time of deformation.

The cross-helical braid for the pair of reinforcing elements is in accordance with that customary for braid reinforcement in pressure-resistant rubber hoses, for example, in which case:
In contrast to the braiding angle which is close to the so-called resting angle (55°44'), in this invention, the above-mentioned resting angle is desirable so as to reach the above-mentioned resting angle at the maximum expansion diameter (shortest length) due to internal pressure filling of the tubular body. is the initial value of the braid angle θ _p is 20°
It is possible to set the usage conditions while the strain ε for normal use reaches approximately 0.3.

The reinforcing elements used in this braiding are suitable for organic or inorganic high tensile strength fibers, such as aromatic polyamide fibers (Kevlar: trade name), twisted or untwisted bundles of filaments such as ultrafine metal wires.

Although the braiding operation on the outer periphery of the tubular body is not necessarily easy under a considerably low angular arrangement such as the above-mentioned initial value of 20 degrees, for example, the braided body obtained with a normal rubber hose braiding machine can be It is convenient to use it as reinforcement for the outer periphery of the tubular body in a state in which it is stretched in the axial direction so as to fit the above, and in this case, adhesive may be applied to the outer periphery of the tubular body as appropriate.

Furthermore, the outer periphery of this braid can be suitably provided with a weather-resistant, trauma-resistant protective coating.

(Embodiment) Now, Fig. 1 shows the external appearance of a preferred embodiment of a torque actuator using air as the working fluid according to the present invention, Fig. 2 shows a cross section of the main part, and Fig. 3 shows the internal structure of the rotating body. expressed.

In the figure, 1 is a holding rod, 2 is a rotary drum, 3 is an elastic contractile body, and 4 is an output shaft.

In this example, a sun gear 5 is coaxially attached to the end of the holding rod 1 by a reamer bolt 6, and the rotary cylinder 2 is supported on the boss of the sun gear 5 via a rolling bearing 7. 8 is a restraining wheel.

The elastic contractile body 3 is a tubular body made of rubber or a rubber-like elastic material, which is reinforced with outer periphery and is braided as described above, and has an appearance similar to a pressure-resistant rubber hose and has a total length that extends almost around the rotating body 2, An embolus (not shown in the figure) is provided at the center of the length of the tubular body to tightly fit the inner periphery of the tubular body and airtightly seal both sides of the body. It is fixed to the top of the outer periphery of the body 2.

In other words, 9 is a pedestal for this fixation, and 10 is a presser metal fitting, in which two semicircular holes having an appearance similar to a plain bearing are formed, and the elastic contractile body is sandwiched between these and bolted.

Both ends of the elastic retractable body 3 fit tightly into insertion nip 12 serving as a closing member with a connecting hole on both sides of the tip of a retaining arm 11 formed overhanging the outer periphery of the rotating barrel 2 from the retaining rod.
3. Caulk and secure.

The insertion nipple 12 connects its air guide hole 14 to a pipe 16 (Fig. 1) that communicates with the pressure operation source S through a ventilation hole 15 bored in the holding arm 11, 17 is its connection port, and 18 is an operation valve. It is.

A transmission gear 2 includes a planetary pinion 19 that meshes with the sun gear 5 and rolls around it.
0, the intermediate gear 2 is wedged to the intermediate shaft 21 and supported by a bearing, and also meshes with the transmission gear 20.
A driven gear 23 that meshes with 2 is wedged to the output shaft 4, and the output shaft 4 is connected to the holding rod 1 by a rolling bearing 2.
4.

In the figure, numeral 25 denotes a cover plate of the rotating body 2, which has bearings 26 and 27 that serve to support the intermediate shaft 21 and the output shaft 4. The cover plate 25 is fixed with screws on a seat 28 (FIG. 3) formed on the rotating body 2.

(Function) Now, by introducing working air from the action valve 18 to the right side of the elastic contracting body 3, contraction occurs in the direction shown by the arrow α, and the rotary cylinder 2 rotates in the same direction. 19 revolves around the sun gear 5 as shown by the arrow β, the driven gear 23 and thus the output shaft 4 rotates as shown by the arrow γ. Conversely, it is clear that by exhausting the air from the right side of the elastic contracting body 3 and applying control pressure to the left side, a rotational output in the opposite direction can be obtained.

As shown in FIG. 2, during this rotation, a rotational position detector 28 of, for example, a rotary encoder is provided in the rotating barrel 2 so as to increase the rotational speed several times from the output shaft 4 through a gear mechanism 29-30. By applying the present invention to detect minute rotational angles, the positional control of the rotational angular displacement of the output shaft 4 can be performed particularly advantageously and appropriately. This is because, as is clear from equation (1) above, the contractile force of the elastic contractile body 3 shows a tendency to gradually decrease as the displacement increases.

This output shaft 4 is equipped with a vacuum suction cup, for example.
A gripping mechanism such as a clamp that opens and closes the jaw by pantograph movement is provided using thrust from an air cylinder or the like, and is used to guide the necessary rotational angle displacement of the object gripped and held.

Further, the holding rod 1 is connected to a suitable articulated arm, and its bending/extending and rotational movements are guided to the holding rod 1, and are used for operating the manipulator along with the rotational output from the torque actuator according to the present invention. .

In addition, in the embodiment described above, gear trains 5, 19, 2
0, 22, and 23, the case where a planetary gear mechanism is used has been explained, but instead, for example, an internally toothed sector gear that is concentric with the output shaft 4 is fixed along the inner circumference of the rotating body 2, and an idler is used. A gear train or the like that transmits power to the driven gear 23 may be installed inside the rotating body 2.

(Effects of the Invention) According to the present invention, the angular displacement of the rotary cylinder due to the elastic contraction force generated in the elastic contractile body is outputted accurately to minute angular displacements through the speed-up gear train incorporated inside the rotary cylinder. Since it can be appropriately guided with a simple configuration, it is possible to conveniently generate torque for manipulator operation.

[Brief explanation of the drawing]

FIG. 1 is an external perspective view, FIG. 2 is a sectional view, and FIG. 3 is an internal view of the rotary drum. DESCRIPTION OF SYMBOLS 1... Holding rod, 2... Rotating body, 3... Elastic contractile body, 4... Output shaft, 11... Holding arm,
5, 19, 20, 22, 23... Gear train.

Claims (1)

[Claims] 1. A rotary cylinder supported by a bearing at the end of the holding rod, an elastic shrinkable cylinder arranged along the outer circumference of the rotary cylinder over a length corresponding to its circumference, and a concentrically supported member inside the rotary cylinder. The elastic cylinder has an output shaft that is transmission-connected to the rotating cylinder through a speed-increasing gear train built inside the rotating cylinder, and the elastic contraction cylinder has a pair of reinforcing elements made of filaments of organic or inorganic high-tensile fibers wound in a cross-wound manner. The embolus is tightly fitted inside the tubular body at a position that bisects the entire length of the tubular body, and the length of the tubular body is The center of the tube is fixed to the outer periphery of the rotating barrel, while the ends of the tubular body are closely fitted to the insertion nipples of a retaining arm formed overhanging the outer periphery of the rotating barrel from the retaining rod. A torque actuator that is constructed by connecting piping that selectively connects each internal part to a pressure control source.