SU1511112A1 - Mechanism for balancing manipulator - Google Patents

Abstract

The invention relates to mechanical engineering and can be used in various robotic devices. The purpose of the invention is to eliminate emergency situations by eliminating the spontaneous movement of the links of the manipulator. In the neutral position, the longitudinal axis of the swivel link 1, pivotally mounted on the base 6, is located vertically. By preloading the spring 9, one end of which is rigidly fixed to the base and the other connected to the main roller chain 5, additional roller chains 3 and 4, each of which is connected to chain 5, interact with deflecting units 7 and 8, also hinged on the base. This prevents spontaneous exit of link 1 from the neutral position, since chains 3 and 4 are pivotally connected to the pivot link. When the link 1 is rotated, under the action of the manipulator actuator, one of the additional roller chains turns out to be unloaded, and the other interacts with the teeth of the toothed sector 2 rigidly fixed on the rotary link, and transmits the counterbalancing force of the spring 9 to it.

Description

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The invention relates to mechanical engineering and can be used in various robotic devices.

The purpose of the invention is to eliminate emergency situations by eliminating the spontaneous movement of the links of the manipulator.

FIG. Figure 1 shows the mechanism for balancing the manipulator with the rotary link in the neutral position; in fig. 2 - the same, when the rotary link deviates from the neutral position; Fig, 3 is a design diagram of the mechanism without taking into account the work of the toothed sector; in fig. 4 - graphs of moments without the work of the gear sector; in fig. 5 is a design diagram of the mechanism taking into account the influence of the operation of the toothed sector; FIG. 6 - graphs of moments, taking into account the influence of the work of the toothed sector; in fig. 7 is a diagram for determining the magnitude of spring preload.

The trimming mechanism of the manipulator contains a gear sector 2 fixed on the hinge axis i toothed sector 2, along the edges of which additional roller chains 3 and A are rigidly fixed, the main roller chain 5, on both sides of which, on the base 6, deflection blocks 7 and 8, and the second end of the chain 5 is connected to a spring 9 fixed to the base 6.

The balancing mechanism works as follows.

In the neutral position, the longitudinal axis of the pivot link 1 is vertical. At the same time, due to the preliminary installation of springs 9, additional roller chains 3 and 4 interact with deflecting blocks 7 and 8, which prevents the spontaneous release of link 1 from the neutral position. When the link 1 rotates under the action of the manipulator actuator (not shown), one of the additional roller chains, for example, 4, is unloaded, and the other interacts with the teeth of the toothed sector 2 rigidly fixed on the rotary link. With the horizontal arrangement of the rotary link 1, the moment created by the force of the spring has a maximum value. When the manipulator is moved upwards, the magnitude of the moment from the mass of the link 1 with the load changes according to the sinusoid law. In order to ensure high precision, the balancing moment due to the force generated by the spring 9 must also vary according to the law of the sine wave. However, the force of the spring 9 when it is compressed is not constant and varies linearly. In this case, when turning

at the angle d, the moments from the mass of the link 1 with the load and from the force of the compression of the spring 9 are unequal (Fig. 4), i.e. RG cosof i mgl cos d, with the magnitude of the inequality

 cos o -Pl cos in (

Therefore, to compensate for changes in the balancing force in order to provide the necessary moment of equilibrium when the link 1 is rotated within a certain angle (the arm must be kept unchanged (Fig. 5). This is achieved by adding an additional end point

body roller chains are spaced apart

the distance a, which is determined by the preliminary compression of the spring 9. At the same time, the moment created by the strengthening of the preliminary compression of the spring

9, is determined by the moment of the mass of the forearm of the manipulator with the load (Fig. 7) with the vertical position of the pivot link 1 and the horizontal position of the forearm. but

the value of the moment created by the preliminary compression of the spring 9 should not exceed the value of the moment created by the power module of the manipulator.

The use of the toothed sector, fixing on it at different points of the additional roller chains at a certain distance, creating a preliminary tension of the chain makes it possible to reduce, by balancing, the 4I value to a minimum, practically in section 1 (Fig. 6). F (z) l mgl cos sec /.

50

Claims (1)

Invention Formula A trimming mechanism for the manipulator comprising a base, a pivot link, pivotally connected 55 to the base, a spring rigidly fixed at one end on the base and kinematically connected to the pivot link by means of the main roller chain, as well as deflecting blocks pivotally mounted on the base, differing that, in order to eliminate emergency situations by eliminating the spontaneous movement of the links of the manipulator, it is equipped with two additional roller chains, each of which is articulated one end with a rotary link, as well as a toothed sector rigidly mounted on this link and having the ability to interact alternately with each of the additional roller chains, the second ends of these chains are pivotally connected to the second end of the main roller chain, and the additional roller chains interact with with Q corresponding deflection blocks. 2 f (z) l cOS (i mi lcosa. wasp FIG. five f (z} t / Ki lcasii HZ) (P.