RU2818234C1 - Stand for calibration and testing of motion parameter sensors - Google Patents

Abstract

FIELD: test equipment.

SUBSTANCE: invention relates to test equipment for objects exposed to mechanical factors causing overloads. Device consists of fixed base on which cranks are installed on axes, drive motor with pulley, connecting rod with a platform for mounting sensors, wherein two cranks of the same radius are made in the form of discs, which are driven by an electric motor with controlled revolutions through a pulley, platform for installation of sensors is installed on connecting rod hinged on cranks. This design of the drive makes it possible to expand functional capabilities, to reduce error of test results and to reduce time for testing.

EFFECT: broader functional capabilities, high accuracy of test results.

1 cl, 2 dwg

Description

The present invention relates to testing equipment and is intended to reproduce the parameters of reciprocating motion when testing and calibrating motion parameter sensors.

As a result of patent research, devices possessing all the essential features inherent in the proposed device were not found.

There are many types of vibrator circuits, including crank-rod and crank-rod, used to reproduce low-frequency reciprocating motion.

The device closest to the proposed invention is a vibration stand with an eccentric drive [1], containing a slider (platform with a rod), a connecting rod and a crank (eccentric).

All of the mentioned devices have significant drawbacks, leading to a significant deviation of the law of reproducible motion from the harmonic one, the main sources of which are fluctuations in the angular velocity of the crank, caused by a variable moment of resistance to rotation, and gaps in the hinges.

To solve the technical problem of eliminating these shortcomings and achieving a technical result - increasing the accuracy of test results and expanding functionality, this invention is proposed. A positive result is achieved by the fact that in the proposed device, which contains two cranks of the same radius and a platform for the sensors being tested, the platform is mounted on a connecting rod pivotally connected to the cranks.

The appearance of the device is shown in the photograph of Fig. 1.

The essence of the proposed technical solution is illustrated by the figure in Fig. 2, which schematically shows the general view of the device.

The device contains a fixed base (frame) 1, on which cranks of the same radius 3 with balancers 4 are installed on axes 2; the cranks have the shape of disks and are driven by an electric motor with an adjustable number of revolutions through a pulley 5. A connecting rod is attached to the ends of the cranks 3 through bearing units 6 7 with a platform for mounting test 8 and model 9 sensors. The diameter of pulley 5 is determined by the required value of the rotation speed of the cranks.

The device works as follows. The bed is fixed on a strong, stationary base to ensure the required orientation of the plane of rotation of the cranks (horizontally or vertically). With the sensors installed, the cranks are balanced. The rotation speed and diameter of the electric motor drive pulley are selected. The electric motor pulley is engaged with the crank discs. After turning on the electric motor, the platform with sensors begins to move forward in a circular path, maintaining its spatial orientation. In this case, the parameters of the platform’s movement along any direction of movement that does not change over time are described by the expressions:

L=Rsin(ω t),

V=ωRcos(ω t),

J=- ω ² Rsin(ω t),

where L is the movement of the platform;

V - platform speed;

J - platform acceleration;

ω - angular velocity of the crank;

t - time;

R - crank radius.

The platform drive circuit of the proposed device practically eliminates the change in time of the moment of resistance to rotation of the cranks, which significantly reduces the errors in test results arising from the variability of the speed of rotation of the cranks and backlash in the hinge units, and also makes it possible to determine the values of the platform movement parameters without using a reference sensor.

The nature of the motion of the platform of the proposed device makes it possible to evaluate the parameters of multicomponent sensors by components located in the plane of motion of the platform simultaneously based on the results of one experiment, which is a sign of expanded functionality and significantly reduces testing time. In this case, there are no requirements for the orientation of the sensors in the plane of motion, i.e. in this case there is no error due to orientation error inherent in stands with purely linear movement.

Thus, the proposed device design makes it possible to achieve a technical result - increasing the accuracy of test results and expanding functionality.

The proposed invention can be used in research and testing institutions of the Ministry of Defense and organizations engaged in research and testing of objects exposed to mechanical factors that cause overloads.

A source of information:

1. Iorish Yu.I. Vibrometry. M., “Mechanical Engineering”, 1963, 356 p.

Claims (1)

A stand for calibration and testing of motion parameter sensors, consisting of a frame, a crank mechanism, a platform for mounting sensors, characterized in that the crank mechanism consists of two cranks of the same radius in the form of disks located in the same plane and driven into rotation through an engine pulley adjacent to them, while the platform for attaching the sensors is installed on a connecting rod, pivotally mounted on the cranks, which ensures the translational movement of the platform with the sensors along a circular path.