JPS6027840A - Shock tester - Google Patents

Abstract

PURPOSE:To make it possible to generate the same impact acceleration for a long time with good reproducibility, by providing an acceleration detector, which is attached to a sample table and detects the actual impact acceleration, computing the impact acceleration, and automatically correcting the acceleration distance. CONSTITUTION:An acceleration detector 14 is attached to a sample table 1. The output signal from the detector 14 is guided to an operation circuit comprising an amplifier 15, a memory circuit 16, a computer 17, a pulse-motor driving circuit 18 and a reference value input circuit 19. The output of the pulse-motor driving circuit 18 is applied to a pulse motor 12. In this constitution, impact acceleration is computed, and the acceleration distance (equivalent free falling height) can be automatically corrected. Thus the same impact acceleration can be generated for a long time with good reproducibility.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an impact testing machine that is effective when used in a manufacturing process to test the characteristics of parts at the same impact acceleration that can occur.

The conventional configuration of a falling weight impact tester that applies a pulsed impact to mechanical parts or electrical/electronic parts is a frame or bed with a guide to support the sample stand when it falls, a sample stand, and It consists of a cylinder or hoisting device that lifts the sample stage to a set height. The impact acceleration is then monitored using an acceleration detector attached to the sample stage and captured using an oscilloscope as the C signal, an open-loop system that attempts to maintain impact acceleration with good reproducibility over the long term. There is no function.

The drop weight impact tester with the conventional configuration described above is affected by changes in the characteristics of the pad sprayed on both the sample stand and the bed, as well as changes in the friction coefficient of the sliding part between the sample stand and the bed. However, there is a problem in that the impact acceleration cannot be maintained constant over a long period of time. In other words, with conventional drop weight impact testing machines, the impact acceleration gradually changes over long periods of operation, so it is suitable for use in the manufacturing process where the same impact acceleration is applied to parts and the characteristics of the parts are tested. It wasn't a test machine.

The present invention was developed in view of the above problems, and it is an object of the present invention to provide an impact tester that can generate the same impact acceleration over a long period of time with good reproducibility.

Therefore, according to the present invention, a self-contained system comprising a V-gear, an acceleration detector attached to the sample stage, a calculation means, a pulse motor, and a ball screw is provided. An impact testing machine equipped with a extraction@structure compares the measured impact acceleration curve obtained from the Torahong Sa Jl, acceleration conversion 1111 domain with the required impact acceleration curve using calculation means such as a conbeater, and calculates the required impact acceleration. Determine the amount of correction for the acceleration distance that will yield the desired model, and then command this value to the automatic correction mechanism. The automatic correction mechanism adjusts the corrected appropriate acceleration distance 14III.
``!'' adjusts the sample stage and waits until the start of the next cycle.This enables automatic correction of the impact tester. Let us explain z′.

In Figures 11xj to 5, the sample stage 1 is held in the left and right directions by bearings 4 with respect to the guide post 3 fastened to the top surface of the bed 2, and can slide up and down. In addition, a rod 5 is attached to the lower surface of the sample table 1 and can be moved up and down together with the sample table 1.An upper rod 6 is attached to the bottom surface of the sample table 1 and can move up and down together with the sample table 1. It is well known that in combination with the lower pad 7 both pads 6.7 are repelled. A roller 8 is attached to the end of the rod 5 to reduce the frictional resistance between the horizontal cylinder 9 and the claw IO, which moves from side to side by the water modulation cylinder 9.The horizontal cylinder 9 and the claw IO are connected as a unit by a ball screw 11. They are combined so that they are moved up and down as one, and they move up and down by a correction amount in accordance with the amount of rotation of the pulse motor 12.

The vertical cylinder 13 lifts the horizontal cylinder 9 and the low IO to a fixed size, that is, to the theoretical falling height, and in turn lifts the sample stage 1 to the same height via the rod 5.

An acceleration detector 14 (not shown) is attached to the sample stage 1, and the output signal of this detector is transmitted to an amplifier 15, a memory circuit 16, and a converter 17, as shown in FIG.
, a pulse motor drive circuit 18, and a standard value input circuit 19, and is added to the output of the pulse motor drive circuit L8 trit<tvy, -E=-ta 12.

The operation of the impact tester having the above-mentioned IS solid structure will be explained in order.

At the descending end of the flying stone cylinder 13, the horizontal cylinder 9 is moved 1:1 (10) to the lower side of the roller 8.

At this time, the pulse motor 12 is at the theoretical rotation amount position, that is, the bearing screw 11 has set the horizontal cylinder 9 and pawl lO unit at the light period correction amount position, so the vertical cylinder 13 using said unit 9.
When the IO is pushed up, the sample stage 1 is lifted up via the rod 5 to the theoretical fall height.

After this, the horizontal cylinder 9 pulls out the claw lO in the horizontal direction at high speed, so the roller 8 does not lose its lower support, and the sample stage 1t
;l: Starts free fall along the guide post 3 together with the rod 5. Then, the upper pad 6 tightened to the lower surface of the sample stage 1 is fixed to the F pad 7 tightened to the upper surface of the pet 2.
When a tuna collides with a tuna, impact acceleration occurs. In addition, since the acceleration detector 14 attached to the sample stage 1 generates the surface line IIV'I velocity as r←; pressure, this is amplified by the amplifier 15 and recorded in the memory circuit 16 as the actually measured shock acceleration curve (5). T does. After that, the vertical cylinder 13
to lower the horizontal cylinder 9 and claw IO unit.

The measured impact acceleration curve obtained in this way is compared with the desired impact acceleration curve given by the standard value input circuit 19 in the combiner 17, the difference is calculated as a correction amount, and the difference is calculated as a correction amount. command to the pulse motor 12.

Since the pulse motor 12Fi rotates to a rotation angle corresponding to the amount of correction, the unit of the water cylinder 9 and claw 10, which are connected to the ball screw 11, has a height correction scale for the theoretical fall height Hl. The appropriate falling height H can be obtained (see Figure 3).

In this way, a series of operation sequences including the automatic correction function are completed, and the system waits until the start of the next cycle in order to perform the same operation again.

In this embodiment, as shown in FIG. 4, ! =(, consider the impact acceleration curve C as a hasrsine curve, and let the points where the curve C crosses the acceleration α-0 be A and B2, this point A-B
The time interval between them is defined as "period" T, the value of the highest acceleration (6) is defined as maximum acceleration "arn", and the integral value between points A and B on curve C is defined as "velocity" (2). These three elements (T,
crm, V) is compared with the required value and fed back as a correction fin for the falling height.

Further, if a re-fall prevention device 20 is added to the lower surface of the bed 2 to catch the rod 5 during the first jump and eliminate the impact caused by the re-fall, it will be even more effective and the cycle time can be shortened.

As other embodiments, in the embodiments described above, a combination of a pulse motor 12 and a ball screw 11 has been explained as a fall height correction mechanism of a falling weight type impact tester, but the present invention is also applicable to other "rotation mechanisms". A height setting mechanism including screws, screws, etc. can also be used. In addition, not only a drop weight type impact tester but also a pneumatic acceleration type impact tester can achieve the same effect by adding an automatic correction mechanism for the acceleration distance. The same applies even if automatic correction is performed. Further, among the three elements that determine the impact acceleration curve, that is, maximum acceleration (6 m), velocity (t), and period (2), the number and combination of the elements that perform the impact acceleration are also free.

As described above, since the impact tester according to the present invention has the above configuration, the impact acceleration curve is calculated and the acceleration distance is 1i1m.
By automatically correcting the (equivalent free fall height), there is an excellent effect that the same impact acceleration can be generated with good reproducibility over a long period of time. Therefore, the effectiveness of its use as fully automatic production equipment is great.

[Brief explanation of the drawing]

Fig. 1 is a side view showing an embodiment of the testing machine of the present invention in which an automatic correction mechanism is added to an example of a conventional falling weight type impact testing machine, and Fig. 2 is a front view of the part of this automatic correction mechanism. , 3rd
The figure is a schematic diagram showing the fall height correction situation, Figure 4 is a curve diagram showing an example of the generated impact acceleration curve and the names of each element of this curve, and Figure 5 is a curve diagram used in the test machine of the present invention. FIG. 2 is a block diagram of the system. 1...-Sample stand, 11... Pole screw, 12...
・Pulse mode Fig. 2 Fig. 1 Fig. 3 JP-A-Sho GO-27840 (4) Fig. 5 9/8

Claims (1)

[Claims] an acceleration detector for detecting the impact acceleration at the point of failure on the sample stage; a calculation means for comparing the impact acceleration at the point of failure with the required impact acceleration and calculating the difference as a correction amount; An impact tester comprising: an automatic correction mechanism for finely adjusting the acceleration distance of the sample stage based on the output of the calculation means.