SK500382013A3 - Actuator with serially attached muscles - I. - Google Patents

Abstract

The actuator with serially connected artificial muscles - I. is formed by a base plate (1) with fixedly connected two columns (2), to which bearing bushes (3) are fixed. Despite this, the drive shaft (21) inserted is rigidly connected to the drive roller (15). The artificial muscles (6) and (36) are attached at one end to the front holders (4) by means of clips (14) and at the same time opposite ends of the artificial muscles (6) and (36) are attached to the artificial muscles (16) and (26) by flexible. bands (10) and (11). These are threaded onto the respective pulleys (5) and (25) which are slid onto the pulley shafts (7) located in the rear brackets (18) connected to the posts (2). The opposite ends of the artificial muscles (16) and (26) are connected by a drive flexible belt (13) threaded onto the drive pulley (15) fixedly coupled to the drive shaft (21) to which the hub of the actuator arm (12) is fixedly connected to arm (8) and this is connected with the load (9).

Description

Actuator with serially connected artificial muscles -1.

Technical field

The technical solution concerns an actuator with artificial muscles in series connection. Artificial muscle actuator is an automation and robotics device where light, powerful and movable drives are usually used.

BACKGROUND OF THE INVENTION

Current rotary motion generating devices using pneumatic artificial muscles are designed as mechanical systems with two rigidly anchored artificial muscles that are connected by opposite ends of the flexural belt. This belt is threaded onto the circumference of the rotary roller which is slid onto the actuator shaft and is supported by bearings located at the ends of the actuator support posts. The actuator thus constitutes an assembly where the columns are mounted on the support plate and at their ends there are bearings, a shaft and a load arm, with the artificial muscles positioned along the columns. Such an actuator forms a relatively long and slender unit with satisfactory weight and size characteristics. The actuator function is such that the initial position of the arm is adjusted by filling both pneumatic artificial muscles to a certain (maximum) pressure of the gaseous medium (air). Muscles, due to the same contraction, define the position of the actuator arm to a reference (starting) position parallel to the longitudinal axis of the actuator. By discharging the gas from one artificial muscle, it is prolonged and at the same time the other artificial muscle contractions, which is still under initial pressure. This action causes the displacement of the flexible belt and at the same time the rolling of the circular pulley accompanied by the rotation of the shaft. Thus, by varying the pressure in one artificial muscle at a constant pressure in the other artificial muscle, any position within a given range and direction can be achieved. When changing the controlled artificial muscle, the deflections are achieved in the opposite direction with an unchanged range. Each rotation of the shaft (caused by the loss of a certain volume of air from the respective artificial muscle) is given by the equality of torques between the artificial muscles. The extent of rotation thus obtained is determined by the radius of the pulley and the extent of contraction of the artificial muscles. The contraction of artificial muscle is directly proportional to its length. Relatively long artificial muscles must be used for larger actuator shaft rotation ranges. This extends the overall length of the actuator to a disproportionate and sometimes inappropriate dimension, which may limit the applicability of the actuator to the working conditions.

SUMMARY OF THE INVENTION

This drawback removes the proposed technical solution, which is based on the concept of creating angular displacement of the actuator drive shaft by applying two pairs of consecutive (serially) connected artificial muscles. Each pair replaces the original long artificial muscle of the required performance and contraction. The geometrical arrangement of the two pairs makes it possible to create an actuator that is almost half shorter than an actuator with only two long artificial muscles. One of the artificial muscles in each pair is attached with one end to the front brackets, the opposite ends are connected in each pair by a flexible belt with the other artificial muscle of the pair. This belt is in each pair threaded onto a respective pulley which is slid into the rear holder and the respective pulley shaft is slid into both pulleys. The second artificial muscle in the pair is connected to the corresponding muscle of another pair of artificial muscles in the opposite end by a driving flexural band. At the same time, the driving flexible belt abuts the actuator shaft pulley. This shaft is slid into the actuator bearing bushes. At the same time, the actuator arm hub is connected to the shaft to which the load is attached.

Each pair of artificial muscles replacing the long artificial muscle of the desired power and contraction has the artificial muscles arranged sequentially connected by a flexural belt through the respective pulley, with the unchanged force adding up the magnitude of their contractions. The two pairs of artificial muscles are arranged antagonistic to each other in the actuator. Such an actuator has twice the range of angular displacements achieved than an actuator with only two of the same artificial muscles of the same type. The pulleys of both pairs of artificial muscles serve, in addition to summing the contractions of individual artificial muscles, to compensate for short-term inequalities of movements and strokes between individual artificial muscles. This may be due to individual material and dimensional differences between individual muscles. It is also necessary that each pair of artificial muscles be fed by a pressure medium from a common electro-pneumatic valve and that the inlets between the artificial muscles and the electro-pneumatic valve have the same length. The same applies to the discharge electropneumatic valve and its inlets. The above condition applies when controlling the movement of the actuator shaft in the respective direction by means of one control signal per pair. In the case of feeding each artificial muscle in each pair of artificial muscles from a separate electropneumatic valve, i. two independent signals, the resulting position of the actuator shaft will be proportional to the sum of these signals.

The two pairs of serially connected artificial muscles can be installed so that the planes of their pulleys are parallel to the plane of the driving pulley (the artificial muscles in the pair are above each other) or so that these planes are perpendicular to each other (the artificial muscles in the pair are side by side).

The proposed technical solution envisages the use of pulleys and a pulley with any surface, i. toothed for chain or toothed belt drives, eventually smooth for flat, V-belts, for cableways and the like. The main advantage of the proposed solution is the possibility to create actuators with twice the range of maximum angular displacement of the actuator drive shaft at half the length of the actuator.

BRIEF DESCRIPTION OF THE DRAWINGS

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows the overall arrangement of the functional parts of the device in front view, and FIG. 2 shows the overall arrangement of the functional parts of the device in a side view.

DETAILED DESCRIPTION OF THE INVENTION

In FIG. 1 and FIG. 2 shows an embodiment of the invention. It shows the overall arrangement of the functional parts of the device. Actuator with serially connected artificial muscles -1. it consists of a base plate 1 with two columns 2 fixedly connected to which the bearing bushes 3 are fixedly connected. A drive shaft 21 is fixedly connected thereto with a drive pulley 15, on which a flexible belt 13, the ends of which are connected to artificial muscles 16 and 26. The artificial muscles 6 and 36 are attached to the front brackets 4 by one end via clips 14. Opposite ends of the artificial muscles 6 and 36 are connected to the artificial muscles 16 and 26 by flexible bands 10 and 11 which are threaded onto respective pulleys 5 and 16. 25. The pulleys 5 and 25 are slid onto the pulley shafts 7, which are located in the rear brackets 18 connected to the posts 2. Opposite ends of the artificial muscles 16 and 26 are connected by a drive bending band 13 fitted to a drive pulley 15 which is fixedly connected to the shaft. 21 actuator. This shaft 21 is slid into the bearing bushes of the actuator 3. At the same time, the shaft 12 of the actuator arm is connected to the arm 8 and this is connected to the load 9.

Industrial usability

The device according to the proposed solution can be used in short and long term application of functional units in which pneumatic or other artificial muscles are used in individual, antagonistic or other connection. The system of the device can also be used on other actuators (electric, hydraulic), their dimensions and performance depend on the size of the equipment used. The device can be used individually, but can also be mechanically interconnected into more complex units (eg in robotics).

Claims (1)

Actuator with serially connected artificial muscles, characterized in that it consists of a base plate (1) with fixedly connected two columns (2), to which bearing bushes (3) are fixedly connected, through which the drive shaft (21) is fixedly connected with a drive pulley (15), wherein the artificial muscles (6) and (36) are attached at one end to the front brackets (4) by clips (14) and at the same time the opposite ends of the artificial muscles (6) and (36) are attached to the artificial muscles ( 16) and (26) by flexible belts (10) and (11) which are slid onto respective pulleys (5) and (25) slid onto the pulley shafts (7) located in the rear brackets (18) connected to the posts (2) and at the same time, the opposite ends of the artificial muscles (16) and (26) are connected by a drive bending band (13) threaded onto a drive pulley (15) firmly connected to a drive shaft (21) to which the actuator arm hub (12) is rigidly connected (8) and this is associated with the burden (9).