JPS59217003A - Torque actuator - Google Patents

Abstract

PURPOSE:To obtain a suitable rotational output with a simple construction by arranging an elastic contractible member on an outer periphery of a rotary drum, securing both ends thereof to a holding arm and the outer periphery of the rotary drum, respectively, and connecting an output shaft to an inner portion of the rotary drum through a series of gears. CONSTITUTION:An elastic contractible member 3 is arranged on the outer periphery of a rotary drum 2 supported on a hoding rod 1 through a bearing, both ends thereof are fixed to the outer periphery of the rotary drum 2 and a holding arm 11 connected to the holding rod 1, respectively, and an output shaft 4 coaxially supported inside the rotary drum 2 is conneted to the rotary drum 2 through a series of gears 5, 20 and 23, whereby the output shaft 4 can be rotated by supplying fluid into the elastic contractible member 3 and exhausting it from the elastic contractible member 3. Therefore, a suitable rotational output can be obtained with a simple construction.

Description

[Detailed description of the invention] (Technical field) For use in storage, refilling, distribution, and other operations of radioactive materials through the shielding wall of a so-called hot cell, which is surrounded by a protective wall from radioactive contamination during experiments and processing. The manipulator (Magic Hand), which was developed in 1993, has since expanded into a wide range of applications, including the replacement of manual labor, due to the development of robot technology.

The following discussion regarding the improvement of a torque actuator, which is particularly suitable as an operating part of such a manipulator or the like, is placed in the field of robotics technology.

(Prior art and its problems) There are various types of actuators for manipulators installed in the above-mentioned hot cells, but since sparks are unavoidable with motors, especially electric ones, fluid pressure is preferably used when explosion-proofing is required. ,・In this case, the usage is of course general purpose.

Many of the conventional scale actuators are of the so-called air cylinder type, but the cylinder piston solid body is usually made of iron, so its own weight as an operating part tends to be excessive compared to the operating force. In addition,
Particularly in the case of a torque actuator that requires rotational output, the transmission system for converting reciprocating motion becomes complicated.

On the other hand, the airbag type is also known, and in this case, the axial contraction force based on the inflation diameter by applying control pressure to the airbag is used as the operating force, so the airbag itself is lightweight and the sliding parts are In addition to the advantages of not having to worry about frictional force or air leakage, it is also flexible and can generate contractile force while in a curved position.

(Objective of the invention) To advantageously incorporate the advantages of a fluid pressure actuator, of which an air bag is a typical example, into the operation of a torque actuator, and to easily and appropriately obtain rotational output with a simple configuration. That is.

(Structure of the Invention) The above object is advantageously fulfilled by a concept based on the following points.

At the end of the holding rod, an elastic contracting body whose length can be contracted by filling with fluid and restored by discharging is arranged along the outer periphery of the supporting rotating body, and both ends of the body are connected from the holding rod to the rotating body. A torque converter is constructed by connecting an output shaft, which is fixed to a holding arm extending over the outer periphery of the rotary cylinder and the outer periphery of the rotary cylinder, and is supported concentrically inside the rotary cylinder, through transmission through the rotary cylinder and a gear train built inside the rotary cylinder. actuator.

In this torque actuator, the arrangement of the elastic contracting bodies is such that a pair of elastic contracting bodies are divided into each semicircle of the rotary cylinder, and in particular, the inside is divided into 22 parts over almost the entire circumference of the rotary cylinder. A particularly advantageous embodiment is a left and right pair fixed to the outer periphery of the rotary cylinder.

Here, the elastic contractile body has an outer periphery reinforced with a silk braided structure using organic or inorganic high tensile strength fibers as a tension-resistant element, and the openings at both ends are sealed and bonded on at least one side with a closing member having a connecting hole. It mainly consists of a tubular body made of rubber or rubber-like elastic material, and is expressed by the following formula, where P: Control pressure d: Internal diameter of the tubular body θ: Braiding angle; Subscript 0 is the initial value, and subscript X is elastic contraction according to the angle at the time of deformation. generate force.

-The braided structure described in F is similar to the customary case of C-+ for pressure-resistant rubber ports, but in that case, the internal pressure of the tubular body is Preferably, the initial braiding angle is 4+'+O so that the above rest angle is reached at the maximum expansion diameter due to the photon.
When o is about 20°, the normal distortion e・ is approximately 0.3
It is possible to determine the conditions of use until the

The reinforcing elements used in this braided structure 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 tying operation on the outer periphery of the tubular body is not necessarily easy under a considerably low angle arrangement such as the above initial value of 20 degrees, It is convenient to cover the outer periphery of the tubular body in a state where it is stretched in the axial direction so as to match the value, and at this time, adhesive may be applied to the outer periphery of the tubular body as appropriate.

Furthermore, the outer periphery of this braided structure may be provided with a weather-resistant, trauma-resistant protective coating, if appropriate.

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. did.

In the figure, 1 is a holding rod, 2 is a rotating body, 3 is an elastic contraction body, and 4
is the output d111.

In this example, a sun gear 5 is coaxially attached to the end of the holding rod 1 by a reamer pole 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 rubber-like elastic material with a braid-reinforced exterior as described earlier, and has an appearance similar to a pressure-resistant rubber hose. It shall be equipped with an embolus (not shown in the figure) that fits tightly into the inner periphery of the tubular body at the center of its length, airtightly seals both sides, and moves independently. The tubular body is secured and tightened to the top of the outer periphery of the rotating body 2 at the center of its length.

In other words, 9 is a pedestal for this tightening, IO is a holding metal fitting, which has two semicircular holes similar in appearance to a brane bearing, and an elastic contractile body is sandwiched between these and bolted. do.

Both ends of the elastic contractile body 3 are provided with insertion nips/l serving as closing members with connection holes on both ends of a holding arm 11 extending from the holding rod l onto the outer periphery of the rotary barrel 2.
/ 12 and then caulk with the cap 13.

The insertion nipple 12 has its air guide hole 14 connected to the holding arm 1.
It is connected to a pipe 16 (FIG. 1) that communicates a pressure control source S through a vent hole 15 bored in 1, 17 is a connection port thereof, and 18 is a control valve.

Inside the rotating body 2, a planetary pinion 19 that meshes with the sun gear 5 and rolls around it is wedged together with a transmission gear 20 to an intermediate shaft 21, supporting bearings, and an intermediate gear 22 that meshes with the transmission gear 20. Further, a driven gear 23 that meshes with the intermediate gear 22 is wedged to the output shaft 4, and the output shaft 4 is supported by a rolling bearing 24 with respect to the holding rod l.

In the figure, reference numeral 25 denotes a cover plate of the rotating body 2, and the intermediate shaft 21. Output ip!
It has bearings 26, 27 which serve to pivot II4.

The cover plate 25 is fixed with screws on a seat 28 (FIG. 3) formed on the rotating body 2.

Now, by introducing operating air from the operating valve 18 to the right side of the elastic contracting body 3, contraction occurs in the direction shown by the arrow α, and the rotating body 2 rotates in the same direction, so that the planetary pinion 19 moves toward the sun gear 5. The driven gear 23 and, in turn, the output shaft 4 rotate as shown by the arrow r. It is clear that a rotational output in the opposite direction can be obtained by evacuating air from the right side of the elastic contracting body 3 and applying control pressure to the left side.

During this rotation, a rotational position detector 28 such as a rotary encoder is fixed from the output shaft 4 with a gear mechanism 29-80 so as to increase the rotational speed several times, and is used to detect minute rotational angles. As a result, the position control of the rotation angle of the output shaft 4 is carried out in an advantageous and appropriate manner.This is because, as is clear from equation (1) above, the contractile force of the elastic contractile body 3 is This is because IIIJi shows a decreasing tendency with respect to an increase in .

This output shaft 4 is equipped with a gripping device such as a vacuum suction cup or a clamp that uses the thrust of an air cylinder to open and close the jaws using the movement of a hand graph. Use it to guide the necessary rotation.

Also, for the holding rod 1, connect an appropriate joint arm,
The bending, stretching and rotational movements are guided to the holding rod, and together with the rotational output by the torque actuator according to the present invention,
It is used to operate the manipulator.

In addition, in the embodiment described above, the gear train 5-19-20-20-
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 a binion that meshes with the sector gear is fixed. A gear train, in which gears are coaxially fixed and transmits power to the driven gear 23 via an idle, may be installed inside the rotating body 2.

(Effects of the Invention) According to the present invention, the rotational output can be appropriately obtained through the rotary cylinder by the elastic contraction force generated in the elastic contraction body, and is convenient for torque generation for manipulator operation 1. can be given.

[Brief explanation of drawings]

FIG. 1 is an external perspective view, FIG. 2 is a sectional view, and FIG. 3 is an internal view of the rotary drum. l... Holding rod 2... Rotating barrel 3... Elastic contractile body 4... Output shaft 11... Holding arm 5-19-20-22-23... Gear train d1: Applicant Brideston Tire Co., Ltd. Figure 1 Figure 3

Claims (1)

[Scope of Claims] 1. At the end of the holding rod, the bearing is arranged along the outer periphery of the supporting rotating body with an elastic contractible body whose length can be contracted by filling with fluid and restored by discharging the fluid. A holding arm extending from the holding rod onto the outer periphery of the rotary cylinder and an output shaft fixed on the outer periphery of the rotary cylinder and supported concentrically inside the rotary cylinder are connected via the rotary cylinder and a gear train built inside the rotary cylinder. Torque actuator consisting of a transmission connection. λ The torque actuator according to item 1, wherein the elastic contracting bodies are arranged in pairs separated by each half circumference of the rotating body. & The torque actuator according to 2, wherein the elastic contracting body is arranged so as to span almost the entire circumference of the rotary drum, dividing the inside into two parts, and fixing it to the outer periphery of the rotary drum at the bisected position.