RU2023997C1 - Multiple-shock test facility - Google Patents

Abstract

FIELD: test technique. SUBSTANCE: desk 2 for part 3 to be tested made in the form of rocker arm with stops 13 and rollers 7 is periodically lifted and dropped by drive made in the form of cams 5 and 6 arranged symmetrically in respect to rocker arm turning axis. Cams are spaced 180 deg. apart, rotate in opposite directions, and are engageable with rollers. Position of stops and rollers through height and profile of cams are adjustable. Shock pulses are shaped during collision of stops with shock absorbers 9, 10 of brake mechanism mounted on bed under desk. Relations between adjustable design parameters of test facility and desired parameters of pulses are given in description of invention. EFFECT: provision for independent regulation of pre-shock speed, frequency, and length of linear acceleration pulses. 1 dwg

Description

 The invention relates to testing equipment, namely to stands for testing products for multiple impacts.

A known stand for testing products for impact, comprising a bed, a table for placing the test product, made in the form of a rocker arm with stops and rollers, a brake device mounted on the bed under the table, including shock absorbers placed with the possibility of impact with the rocker stops, table guides and lift drive and a reset section configured in the form of symmetrically arranged relative to the pivot axis of the rocker angularly offset from each other by ¹⁸⁰ ° and rotating in opposite directions eccentric c, installed with the possibility of interaction with the rollers [1].

 The disadvantage of the stand is that it allows you to adjust only one parameter of the linear acceleration pulses - the pulse repetition rate.

Closest to the technical nature of the invention is a stand for testing products for impact, containing a bed, a table for placing the test product, made in the form of a rocker arm with stops and rollers mounted with the possibility of height adjustment, mounted on the bed under the table brake device, including shock absorbers placed with the possibility of collision with the rocker arms, table guides and a table lifting and dumping drive, made in the form of omysla angularly offset from each other by ¹⁸⁰ ° and rotating in opposite directions eccentrics mounted to cooperate with rollers [2].

 The technical result that can be obtained by carrying out the invention is to expand the functionality by independently controlling the pre-shock speed, frequency and duration of the linear acceleration pulses.

 The drawing shows a structural diagram of the stand.

The stand for testing products for repeated impacts includes a bed 1, a table 2 made in the form of a rocker and serving to place the test product 3, a drive for lifting and dumping the table, including an engine (not shown) with gear 4 and two gears 4 mounted on the shafts rotatable opposite directions of the eccentric 5 and 6, located with an angular displacement of 180 ^about each other. The eccentrics are configured to interact with the rollers 7 mounted on the table 2.

 Shock absorbers 9 and 10 are installed on the projections 8 of the frame 1, in addition, guides 11 connected to the table 2 with a hinge 12 are mounted on the frame. Table 2 is equipped with stops 13, which, like the rollers 7, are mounted with the possibility of height adjustment.

 Devices for regulating the position of stops 13 and rollers 7 contain adjusting elements 14 and 15, for example, screw-nut pairs. Eccentrics 5 and 6 are made adjustable along the profile. The device for adjusting the profile of the eccentrics contains adjusting elements 16, for example, screw-nut pairs. A device with a hydraulic or pneumatic drive can also be used as a regulating one.

,
P=

X²Δ² -

+ Δ, где
y=n

t_и +

-0,5,
x =

,
Р - расстояние от нижней точки ролика 7 до наиболее близкой к оси вращения точки образующей эксцентрика, в его положении, при котором эта точка образующей находится в крайнем верхнем положении, а стол - в горизонтальном положении;
n - частота вращения эксцентриков;
V - требуемая предударная скорость;
t_и - требуемая длительность импульса;
а - расстояние от вертикальной оси направляющих 11 до оси крепления эксцентриков 5 и 6;
b - расстояние от вертикальной оси направляющих 11 до оси, проходящей через центр упоров 13;
Δ- расстояние между наиболее удаленной и наиболее близкой от оси вращения точками образующих эксцентриков 5 и 6;
g - ускорение свободного падения.Adjustable design parameters of the bench are related to the required parameters of the pulses by the relations
Δ = -

,
P =

X ² Δ ² -

+ Δ, where
y = n

t _and +

-0.5
x =

,
P is the distance from the lower point of the roller 7 to the closest to the axis of rotation of the point of the generatrix of the eccentric, in its position at which this point of the generatrix is in its highest position, and the table is in a horizontal position;
n is the speed of the eccentrics;
V is the required pre-shock speed;
t _and is the required pulse duration;
a is the distance from the vertical axis of the guides 11 to the axis of attachment of the eccentrics 5 and 6;
b is the distance from the vertical axis of the guides 11 to the axis passing through the center of the stops 13;
Δ is the distance between the points of the generating eccentrics 5 and 6 closest to the farthest and closest to the axis of rotation;
g is the acceleration of gravity.

 The stand works as follows.

 The eccentrics 5 and 6, when they rotate from the gearbox 4 through the rollers 7, raise the table 2 in turn. When the eccentric 6 runs on the roller 7, the opposite stops 13 come into contact with the shock absorbers 10 and the table 2 is lifted with a relative rotation around this point. When the top of the eccentric 6 comes out of contact with the roller 7, the table 2 falls on the shock absorbers 9 and the test product 3 perceives vertical linear acceleration and angular acceleration. In the future, the eccentric 5 raises the table 2, with the subsequent release of the table falls on the shock absorbers 10 and the product 3 perceives vertical linear acceleration and angular acceleration in the opposite direction.

 By changing the parameters of the stand n, Δ, p in accordance with the above formulas, it is possible to obtain the required parameters of the pulses, i.e. carry out independent regulation of pulse parameters, which extends the functionality of the stand.

Claims (1)

STAND FOR TESTING PRODUCTS FOR REPEATED SHOCKS, containing a bed, a table for placing the test product, made in the form of a rocker arm with stops and rollers mounted with the ability to adjust their height position, a brake device mounted on the bed under the table, including shock absorbers placed with the possibility of impact with each rocker stops, the table guides and the table lift and reset drive, made in the form of each other symmetrically positioned relative to the axis of rotation of the rocker arm with angular displacement flax other by 180 ^o and rotatable in opposite directions eccentrics set to interact with the rollers, characterized in that the eccentrics are adjustable along the profile, the adjustable stand design parameters associated with the pulse parameters relations treuemymi
Δ = -

,,
P =

X ² Δ ² -

+ Δ,
where y = n

t _and +

-0.5;
x =

;
P is the distance from the lower point of the roller to the point of the eccentric generatrix closest to the axis of rotation in its position at which this generatrix point is in its highest position and the table is in a horizontal position;
n is the speed of the eccentrics;
v is the required pre-shock speed;
t _and is the required pulse duration;
a is the distance from the vertical axis of the guides to the axis of attachment of the eccentric;
b is the distance from the vertical axis of the guides to the axis passing through the center of the stop;
Δ is the distance between the points of the eccentric forming the most remote and closest to the axis of rotation;
g is the acceleration of gravity.