JPH0652229B2 - Drop impact tester - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a drop impact tester used when determining impact cushioning performance or the like of the sole of a running shoe.

[Conventional technology]

In sports shoes such as running shoes, in particular, a large impact force is applied to the heel portion at the time of landing, so that the shock absorbing performance of the sole material of the heel portion is an important point when manufacturing the sports shoe.

By the way, conventionally, to judge the shock absorbing performance of the sole material,
A drop impact tester is used in which an impact imparting body composed of impact force and weight is dropped onto a test body formed of a shoe sole material such as sponge, and the impact force received by the striker at that time is measured.

[Problems to be Solved by the Invention]

However, as described above, when the impact imparting body composed of the impactor and the weight is dropped on the shoe sole material as the test body, and when the person actually wears the sports shoes and runs, the sole material There is a big difference in how the impact force is applied to.

That is, when a person actually wears athletic shoes and runs, the impact force due to the weight of the person is applied to the sole, but since the person's foot has a cushioning part due to joints such as knees and ankles, the sole is The impact force is applied relatively slowly over time, but when the impact force is applied simply by dropping a rigid body as in the above drop impact tester, the impact force is momentarily applied to the test body. Join. When a person actually wears athletic shoes and runs, it is said that the impact force is applied to the heel part at a speed of about 10 Hz, whereas
Approximately 21Hz with a conventional drop impact tester that simply drops a rigid body
It has been confirmed by experiments that the impact force is applied at about twice the speed.

For this reason, when a conventional drop impact tester is used to impact a test piece of highly deformed shoe sole material such as urethane or sponge, the deformation of the sole material that occurs when a person actually wears sports shoes and runs. A deformed state that is completely different from the state occurs in the test body.

Also, in the case of simply dropping a rigid body and applying an impact force to the test body instantly as in the conventional drop impact tester, the impact force will be increased unless the weight of the striker is considerably lighter than the weight of the person. As a result, the deformed state of the test body greatly differs from the actual deformed state of the shoe sole.

For this reason, there is a problem that the determination of the shock absorbing performance of the sole material by the conventional drop impact tester does not match the shock absorbing performance of the sole when a person actually wears running shoes and runs. .

Therefore, the present invention is to apply an impact force to a test piece such as a shoe sole material in a state similar to that when a person actually wears athletic shoes, that is, relatively slowly and slowly. It is a technical object to provide a drop impact tester capable of

[Means for Solving the Problems]

In order to solve the above-mentioned technical problem, the present invention has a buffer portion interposed between a weight and a striker which constitute an impact imparting body of a drop impact tester.

A combination of a coil spring and a hydraulic shock absorber can be used as the shock absorber.

[Action]

When the impact imparting body is dropped onto the test body, the load due to the weight of the impact imparting body is transmitted to the test body through the buffer section, so that the impact force is slowly applied to the test body over time. It

〔Example〕

Next, an embodiment of the present invention will be described with reference to the accompanying drawings.

The drop impact tester is a support base 3 provided with a holding device 2 for pressing and holding a test body 1 such as a shoe sole material such as urethane or sponge, and the test body 1 on the upper surface of the support base 3 is dropped. An impact imparting body including an impacting impacting element 4 and a weight 5 to which an impact is applied, a dropping device for lifting the impacting impacting element upward and dropping it, and adding it to the impacting element 4 when the impact imparting element is dropped onto the test body 1. In the drop impact tester according to the present invention, a shock absorber including a coil spring 6 and a hydraulic shock absorber 7 is provided between the striker 4 and the weight 5 of the impact imparting body. Intervenes.

A pair of left and right guide poles 8 are provided on the upper surface of the support base 3.
Is erected. A mounting frame 9 for the coil spring 6 and the hydraulic shock absorber 7 is attached to the guide arm 10 on the guide pole 8.
It is mounted slidably via. A weight 5 is slidably attached to the guide pole 8 above the attachment frame 9 via a guide arm 11.

The mounting frame 9 includes upper and lower triangular plates 9a, 9b and 9c,
The triangular plate 9a, 9b, 9c is formed by a shaft rod 12 inserted into each corner portion of the triangular plate 9a, 9b, 9c, and between the upper triangular plate 9a and the central triangular plate 9b, and the central triangular plate 9b. A pair of coil springs 6 and a hydraulic shock absorber 7 are fitted between the lower triangular plate 9c and spacer frames 13 and 14, respectively, and the coil spring 6 is installed around the hydraulic shock absorber 7.

The striker 4 is attached to the lower surface of the lower triangular plate 9c between the test body 1 and the lower body.

On both sides of the mounting frame 9, a pair of left and right arms 15 of a dropping device for lifting the weight 5 upward and dropping it on the upper surface of the triangular plate 9a above the mounting frame 9 are installed.
The arm 15 is fixed to an endless chain 18 that is bridged between a pair of upper and lower sprockets 16 and 17 installed on both sides of the mounting frame 9. And the weight 5
Engaging projections 19 are provided on both lower sides of the arm 15 to engage when the arm 15 is rotated upward by the chain 18, and the weight 5 is engaged with the arm 15 and the engaging projection 19. Raised upwards, FIGS. 4 and 5
As shown in the figure, when the arm 15 rotates further upward to rotate around the upper sprocket 16 and the engagement state between the arm 15 and the engaging protrusion 19 is released, the weight 5 is attached to the mounting frame 9. It is designed to drop onto the upper surface of the upper triangular plate 9a. The pair of sprockets 16 and 17 are mounted on a support column 20 standing on the rear side of the mounting frame 9 with brackets 21 and 2.
The supporting column 20 is installed via a vertical axis 2 and is vertically movable by an elevating device provided on the lower surface of the support base 3.
By raising and lowering the support column 20 by this raising and lowering device, the engagement position between the arm 15 and the engaging protrusion 19 of the weight is raised and lowered, whereby the stroke of raising and lowering the weight 5 can be changed. The lifting device is
The rotating handle 23, the two screw rods 26 and 27 rotated by the rotating handle 23, and the screw rods 26 and 2.
7 and a lifting table 28 which moves up and down by screwing. The lower end of the column 20 is integrally attached to the lifting table 28.

Further, the lifting table 28 is provided with a driving device 29 for driving the chain 18 bridged between the pair of sprockets 16 and 17.

As the measuring device, for example, a load sensor 30 can be used, and the load sensor 30 is attached to an intermediate portion of the striker 4. Further, it is preferable that a displacement sensor 32 for measuring the amount of displacement of the test body 1 is attached to the support base 3.

When the shock-absorbing portion is configured by the combination of the coil spring 6 and the hydraulic shock absorber 7 as described above, the strengths of the coil spring 6 and the hydraulic shock absorber 7 analyze the movement of the lower limbs of the person during exercise,
It can be determined by the following equation from the movement of the lower limb and the ground reaction force applied at that time.

Here, k indicates the strength of the coil spring 6, and η indicates the strength of the hydraulic shock absorber 7, respectively.

From the above equation, for example, the coil spring 6 during running
And the coefficient of the hydraulic shock absorber 7 are calculated, k = 2000 Kg / m, η =
It was 2500 Kg / sec / m. In this case, the values of k and η are determined from the landing impact at the time of analyzing the running, so when the conditions are different from the running, such as when landing after an attack like volleyball. The movement is analyzed, and the strengths of the coil spring 6 and the hydraulic shock absorber 7 are appropriately changed according to the analysis.

Next, the operation of the above embodiment will be described.

First, the strength of the coil spring 6 and the hydraulic shock absorber 7 of the shock absorber is
It is set so that a cushioning force that is almost the same as the cushioning force of the joints of the lower limbs according to various exercise conditions is obtained, and then the falling stroke of the weight 5 and the weight of the weight 5 are appropriately changed to perform various exercises. Adjust so that the impact force that meets the conditions is applied to the test body 1. At this time, it is desirable that the weight 5 has a weight of 50 to 60 kg, which is almost the same as the weight of a person.

After that, when the driving device 29 is driven from the state shown in FIG. 2 to rotate the chain 18, the arm 15 rises,
Thereafter, the arm 15 engages with the engaging projection 19 of the weight 5 and the weight 5 rises, and when the arm 15 further rotates upward from the state shown in FIG. 4, the engaging projection 19 between the arm 15 and the weight 5 is formed. As a result, the weight 5 lifted up is dropped onto the upper surface of the triangular plate 9a above the mounting frame 9 as shown in FIG.

The impact force of the weight 5 dropped on the upper surface of the upper triangular plate 9a is generated by the spacer frame 1 on the lower surface of the upper triangular plate 9a.
3 is transmitted to the upper coil spring 6 and the hydraulic shock absorber 7, and then through the central triangular plate 9b, the spacer frame 14, the lower coil spring 6 and the hydraulic shock absorber 7, and the lower triangular plate 9c. The impact force is transmitted to the striker 4, and the impact force is applied to the test body 1 by the striker 4.

The impact force applied to the test body 1 is measured by the load sensor 30 attached to the striker 4, and the displacement sensor 32 of the deformation amount of the test body 1.

〔The invention's effect〕

As described above, according to the drop impact tester of the present invention, the drop impact of the impact imparting body can be imparted to the test body relatively slowly over a time period as compared with the conventional drop impact tester. Therefore, since the impact force is applied to the test body in a state similar to the impact force applied to the shoe sole in the actual exercise state, there is an effect that the impact cushioning performance of the shoe sole material can be correctly determined.

[Brief description of drawings]

FIG. 1 is a front view showing an example of a drop impact tester according to the present invention, FIG. 2 is a side view of the same, and FIG. 3 is a plan view of the same.
FIG. 4 is a partial front view showing the state in which the weight is lifted by the arm, and FIG. 5 is a partial front view showing the state immediately after the weight is dropped. DESCRIPTION OF SYMBOLS 1 ... Test body, 4 ... Impactor, 6 ... Coil spring, 7 ... Hydraulic shock absorber, 15 ... Arm, 19 ... Engagement protrusion, 30 ... Load sensor.

Claims (1)

[Claims] 1. An impact imparting body composed of a striker and a weight, a dropping device for dropping the impact imparting body to the test body, and an impact applied to the striker when the impact imparting body is dropped on the test body. A drop impact tester comprising a measuring device for measuring a child, characterized in that a shock absorbing portion composed of a combination of a coil spring and a hydraulic shock absorber is interposed between the impacting element and the weight of the impact applying body. Drop impact tester.