JP6666178B2 - Goggle hydraulic resistance measuring device - Google Patents

Description

  The present invention relates to a goggle hydraulic resistance measuring device. More specifically, the present invention relates to an apparatus for measuring hydraulic resistance of swimming goggles suitable for swimming.

  A swimming goggle generally includes an eyecup lens, a goggle body including a pad integrated below the eyecup lens, and a belt for attaching the goggle body to a head of a human body. Patent Literature 1 proposes a goggle in which the lower surface is longer than the upper surface of the pad so that water leakage does not occur even when strong water pressure is applied such as when jumping. Patent Document 2 proposes a goggle in which a connecting member is fixed to a side portion of an eyecup and a head strap is connected to the connecting member in order to improve a feeling of wearing. Patent Literature 3 proposes that a convex ridge having a groove be provided on a side surface of an eyecup in order to reduce fluid resistance.

JP 2011-083539 A JP 2012-070794 A JP 2013-104469 A

  However, the conventional goggles have a problem that the goggles are displaced or come off when a strong water pressure is applied at the time of jumping or the like. To solve this problem, a goggle hydraulic resistance measuring device is required. However, such a device has not been found in the past, and development has been requested from the industry.

  SUMMARY OF THE INVENTION The present invention provides a goggle hydraulic resistance measuring device that exerts a strong hydraulic pressure at the time of diving or the like in order to solve the conventional problem.

  The goggles hydraulic resistance measuring device of the present invention is a swimming goggles hydraulic resistance measuring device, wherein a head mannequin equipped with the goggles and a slope rail having a predetermined angle are provided above a pool having standing water. An elevating device that moves up and down along with the elevating device, a support arm fixed to the elevating device, means for jumping the head mannequin fixed to the support arm into a pool, and pressure sensors connected to positions above and below the goggles And a means for measuring a change in water pressure over time and calculating a difference between moments applied to the goggles from respective pressure sensor measurement values.

  The goggles hydraulic resistance measuring device of the present invention includes a lifting device that moves up and down along an inclined rail having a predetermined angle above a pool having standing water, a support arm fixed to the lifting device, and the support device. Means for jumping the head mannequin fixed to the arm into the pool, and pressure sensors connected to the upper and lower positions of the goggles, measure changes in water pressure over time, and add to the goggles from each pressure sensor measurement value By including the means for calculating the difference in moment, it is possible to accurately measure the hydraulic resistance of goggles that are subjected to strong water pressure when jumping in.

FIG. 1 is a schematic perspective view of one embodiment of goggles used in the present invention. FIG. 2 is a schematic perspective view of another embodiment of goggles used in the present invention. FIG. 3 is a schematic sectional view taken along line II of FIG. FIG. 4 is a schematic side view of a hydraulic resistance measuring device according to one embodiment of the present invention. FIG. 5 is a front photograph showing the positional relationship between the pressure sensors arranged above and below the goggles of the head mannequin. FIG. 6 is a front view of the head mannequin with the goggles attached to the head mannequin. FIG. 7 is a graph showing the difference in moment of water pressure applied to the top and bottom of goggles during the dive experiment of Example 1. FIG. 8 is a graph showing the difference in moment of hydraulic pressure applied to the top and bottom of goggles during the dive experiment of the second embodiment. FIG. 9 is a graph showing the difference in moment of hydraulic pressure applied to the top and bottom of the goggles according to the third embodiment. FIG. 10 is a graph showing the difference in moment of hydraulic pressure applied to the top and bottom of the goggles according to the fourth embodiment. FIG. 11 is a graph showing the difference in moment of the water pressure applied to the top and bottom of the goggles according to the fifth embodiment. FIG. 12 is a graph showing a change in speed and load during the measurement time t = 0 to 1.5 seconds in Example 1 and Reference Example 1. FIG. 13 is a graph in which a moving distance is calculated after moving average calculation of a moving distance in a dive experiment according to an embodiment of the present invention. FIG. 14 is a graph of the speed calculated from the approximate curve. FIG. 15 is a graph of the acceleration calculated from the approximate curve. FIG. 16 is a graph of the load calculated from the approximate curve.

  The goggles hydraulic resistance measuring device of the present invention develops goggles free from such problems by analyzing phenomena such as the goggles being displaced, coming off, or being pressed down from below when strong water pressure is applied, such as when jumping in a swim. It was completed for the purpose of doing. This device includes a lifting device that moves up and down along a tilted rail having a predetermined angle above a pool having still water, a support arm fixed to the lifting device, and a head fixed to the support arm. Means for jumping the mannequin into the pool, and means for connecting pressure sensors to the upper and lower positions of the goggles, measuring changes in water pressure over time, and calculating the difference in moment applied to the goggles from each pressure sensor measurement. including.

  The angle of inclination of the inclined rail with respect to the water surface is adjustable, for example, between 30 ° and 50 °, preferably between 35 ° and 45 °, and the water entry speed of the head mannequin is 2.2 m / sec to 6 m. The height of the head mannequin from the water surface is adjusted so as to be 0.0 m / sec. The inclination angle and the water entry speed were obtained from general data on swimming races.

  This will be described below with reference to the drawings. In the drawings, the same reference numerals indicate the same components. FIG. 1 is a schematic perspective view of one embodiment of goggles used in the present invention. The goggles 20 include a goggle body 4 including an eye cup 2 in which the lens 1 is integrally formed, a pad 3 integrated below the eye cup 2, and a head for attaching the goggle body 4 to a human head. It includes a strap 7 and a connecting member 5 for connecting the goggle body 4 and the head strap 7. A slit is formed at the tip of the connecting member 5 in the vertical direction, and the connecting member 5 and the head strap 7 are connected to each other through the head strap 7 through the slit. Reference numeral 6 denotes a connecting portion between the connecting member 5 and the head strap 7. A length adjuster 8 is connected to the head strap 7. The two eyecups 2 are connected by a connecting bridge 9.

  In the goggles, the connecting member 5 is formed of a rubber-like belt, and the connecting member 5 covers the surface of the pad 3, goes around the lower part of the eyecup 2, and extends to the rear side of the goggle body 4. . As a result, the rubber belt presses the entire eyecup against the face with a uniform force, and a stable pressing force acts. Therefore, even when strong water pressure is applied, the goggle body is unlikely to shift or come off the face.

  In addition, the goggles of the present embodiment have a plurality of protrusions 10 in a horizontal row formed on the upper side surface of the eyecup 2. Thereby, the water flow resistance can be further reduced. As the projections, four hemispherical projections having a radius of 1.2 mm were arranged at an interval of 2 mm in a horizontal line on the inclined portion on the upper side surface of the eyecup.

  FIG. 2 is a schematic perspective view of another embodiment of goggles used in the present invention. This is an example of goggles 21 made in the same manner as in FIG. 1 except that no projection is formed on the side surface of the eyecup.

FIG. 3 is a schematic sectional view taken along line II of FIG. The eyecup 2 and the pad 3 are integrally formed, and the connecting member 5 of the rubber-like belt is fitted in a groove formed on the outer surface between the lower part of the eyecup 2 and the pad. In FIG. 3, θ ₁ is the angle between the surface of the lens 1 and the outer inclined portion of the eyecup 2, and θ ₂ is the angle between the parallel line on the surface of the lens 1 and the upper surface of the rubber belt 5. angle is preferably θ _1> θ ₂ between the theta ₁ and theta _2, more preferably greater it is theta ₂ than 5 ° or more theta _1, more preferably greater theta ₂ than 10 ° or more toward the theta _1. As a result, the rubber-like belt presses the entire eyecup against the face with a more uniform force, and a stable pressing force acts. Therefore, even when strong water pressure is applied, the goggle body is less likely to shift or come off the face.

  FIG. 4 is a schematic side view of a hydraulic resistance measurement test according to one embodiment of the present invention. The hydraulic resistance measuring device 18 includes a support arm 13 fixed to an elevating device 14 that moves up and down along an inclined rail 15 above a pool 16 containing water 17 (stationary water), and is fixed to the support arm 13. This is a device for jumping the drawn head mannequin 12 into the pool 16. The goggles 20 are mounted on the head mannequin 12, cover the cap 11, and jump into the water surface. The measured dimensions of the pool are 6.0 m in length, 2.0 m in width, and 1.0 m in water depth. As shown in FIG. 5, pressure sensors having a diameter of 6 mm are connected to the upper and lower positions of the goggles 20 at intervals of 32 mm, so that a change in water pressure over time can be measured. The difference between the moments applied to the goggles 20 can be calculated from the respective pressure sensor measurements. FIG. 6 is a front photograph in which goggles are mounted on a head mannequin and covered with a cap. The inclination angle of the inclined rail with respect to the water surface is adjustable, and the lifting device can be fixed at any position on the inclined rail. As an example, the inclination angle of the inclined rail 15 with respect to the water surface was set to 40 °, the rail was made to enter the water surface from a position at a height of 900 mm from the water surface, and the water surface entry speed was set to about 2.5 m / sec. The analysis followed the following procedure.

The first position sensor is arranged at a position at a height of 433 mm from the water surface, and time measurement is started from the time when the tip (forehead) of the head mannequin 12 has passed. The second position sensor is disposed at the water surface contact position, and measures the time when the tip (forehead) of the head mannequin 12 contacts the water surface. Thereby, the time from the start of the measurement time to the entry into the water surface is known. The moving image of the head mannequin 12 when it entered the water surface was shot as a high-speed moving image (300 fps) using a digital camera (CASIO EX-F1). The measurement conditions were as follows: sampling frequency: 1000 Hz, measurement time: 2 sec, resolution of A / D conversion: 14 bits, and processing was performed using a personal computer. Each data was acquired as a voltage value, and was converted into each physical quantity by post-processing. To summarize the above, the measurement items are as follows.
(1) Position of head mannequin 12 (2) Pressure due to wearing goggles (3) Time from start of measurement time to entry into water surface (4) Movie of head mannequin 12 entering water surface

The analysis followed the following procedure.
(1) The moving distance of the specimen (head mannequin) for 2 seconds from the start of measurement is measured, the speed is calculated from the moving distance, and an approximate curve of the speed is obtained (FIG. 13).
(2) The load is calculated from the approximate curve again by multiplying the acceleration by the speed, acceleration and the weight of each specimen during the measurement time (2 seconds) (FIGS. 14 to 16).
(3) The pressure change when the goggles are attached is converted as the load (N) by multiplying the pressure by the surface area of the pressure sensor (2.83 × 10 ⁻⁵ m ² ).
(4) From the load obtained in the above (2), the maximum value of the load in water due to the presence or absence of goggles and the difference in shape is compared.
(5) The impact force at the time of landing is evaluated from the impulse between “the time of entry into the water surface and the time of the maximum load in water” using the load obtained in (3). Further, the difference between the moment (arm length 0.016 m) at the center position of the two pressure sensors using the load is obtained, and the influence of the displacement of the goggles when the load is maximum in water is evaluated.

  In the above, the impulse (Impulse) is represented by the following equation (Equation 1), and is obtained by multiplying the force (F) by the time during which the force acts.

In this study sought two impulse on the lower sensor sensor from the time t ₁ of water inrush in load maximum time t ₂ in water, it showed the sum I _total resulting. As the sampling time △ t (= 0.001), obtained as follows (Equation 2) and (Equation 3) When the impulse on the sensor I _t, the impulse under the sensor and I _b

Here, F _t and F _b are forces acting on the sensor and below the sensor. Then, the sum I _total of the two impulse is as follows.
I _total = I _t + I _b
Next, the moment was set around a central position connecting the upper and lower portions of the sensor with a straight line. The moment arm length as L (= 0.016), respectively M _t moment at around the central position, when M _b, as follows.
M _t = F _t × L
M _b = F _b × L
Here, the direction in which the goggles pressed the face was positive. Next, the moment difference ΔM is calculated by the following calculation based on the moment on the sensor.
ΔM = M _t −M _b

  Hereinafter, the present invention will be described specifically with reference to examples. The present invention is not limited to the following examples.

(Example 1)
The goggles 20 shown in FIGS. 1 and 3 were produced. The lens 1, the eyecup 2, and the pad 3 were integrally formed of polycarbonate resin, the head strap 7 was formed of silicone rubber, and the rubber-like belt connecting member 5 was formed of polyurethane elastomer. The rubber-like belt connecting member 5 was fitted into a groove formed on the outer surface between the lower portion of the eyecup 2 and the pad 3. In FIG. 3, θ1 was 44.9 ° and θ2 was 31.7 °.
A plurality of protrusions 10 in a horizontal row were formed on the upper side surface of the eyecup 2. As the protrusions 10, four hemispherical protrusions each having a diameter of 1.2 mm were arranged at an interval of 2 mm in a horizontal line on the inclined portion on the upper side surface of the eyecup 2.
The goggles 20 thus obtained were mounted on the head mannequin 12 as shown in FIG. 4, covered with the cap 11, and subjected to a hydraulic resistance measurement test shown in FIG. The number of measurements was three, the average was calculated, and the results are summarized in Table 1. FIG. 7 is a graph showing the moment difference of the water pressure applied to the top and bottom of the goggles in the dive experiment at the time of the first measurement. It can be seen that there is almost no difference in water pressure moment applied above and below the goggles.

(Example 2)
As shown in FIG. 2, goggles 21 were formed in the same manner as in Example 1 except that the projections 10 were not formed. The results are summarized in Table 1. FIG. 8 is a graph showing the moment difference of the water pressure applied to the top and bottom of the goggles during the dive experiment at the time of the first measurement.

(Examples 3 to 5)
A hydraulic resistance measurement test was performed using Mizuno's trade name "Accel Eye Cutter" as Example 3, Mizuno's trade name "Accel Eye" as Example 4, and commercially available competitor's product as Example 5 (number of measurements). 3 average). The results are summarized in Table 1. FIG. 9 shows the result of the first measurement of Example 3, FIG. 10 shows the result of the first measurement of Example 4, and FIG. 11 shows the result of the first measurement of Example 5.

(Reference Example 1)
Table 1 summarizes the results of the measurement in the same manner as in Example 1 without wearing goggles.

The following can be seen from Table 1 and FIGS.
(1) The difference between the moments is the result of taking the direction in which the sensor presses the face as positive around the center between the two sensors. That is, if the difference in the moment is positive, the goggles are turned from below, and if the difference is negative, the force is turned from above. All goggles have a positive difference in moment, and exert a force to flip from below. In the first and second embodiments of the present invention, the difference in moment at the time of water entry is lower than that of the third to fifth embodiments, and the difference between the pressure moments above and below the goggles at the time of maximum load when entering the water surface is 1 × 10 ⁻⁶ N (N : Newton) or less, and the power to turn from below is low.
(2) In Example 3, it can be seen that a large moment force is generated in the eyecup at the time of entering water, and then decreases, and the difference is large. Further, in Example 4, it can be seen that a large moment force is generated in the eyecup when water enters, and a small moment force remains thereafter. In addition, in Example 5, it can be seen that a large moment force is generated in the eyecup at the time of entering water, and then sharply decreases, and the difference is large.
(3) From the average value of the impulse, the impact force of pressing the face acts in the third and fifth embodiments, and the impact force of the goggles coming off the face acts in the fourth embodiment. On the other hand, the impulse of Examples 1 and 2 is low and is not more than 10 × 10 ⁻⁶ Ns (N: Newton, s: second). This indicates that the impact force at the time of entry into the water surface is small, hard to be shifted, and is in close contact with the face.
(4) As described above, in Examples 1 and 2, almost no moment force was generated at the time of entering water, and it was confirmed that the goggles stably adhered to the face. It was also confirmed that displacement was suppressed with low resistance to water pressure.

  FIG. 12 shows changes in speed and load in the measurement time t = 0 to 1.5 seconds in the first embodiment and the reference example 1. However, the data in the figure are the results of the first measurement for clarity. Taking the measurement result of Reference Example 1 as an example, the speed becomes maximum at t = 0.109 seconds, and rapidly decreases when the vehicle enters the water surface at t = 0.134 seconds. The speed becomes a negative value from about 0.9 seconds because the buoyancy of the head mannequin itself causes a force to float on the water surface. The load reaches a negative maximum at t = 0.368 seconds after entering the water surface, and thereafter shows a change in which the negative load gradually decreases. The measurement results of Example 1 were the same as those of Reference Example 1. However, due to the effect of wearing goggles, the speed reduction after entering the water surface was larger than that of Reference Example 1, and the maximum load in water was larger.

  INDUSTRIAL APPLICABILITY The apparatus for measuring hydraulic resistance of swimming goggles according to the present invention is useful for the development of various swimming goggles such as swimming goggles, dive goggles, water polo goggles, synchronized swimming goggles, and general goggles.

REFERENCE SIGNS LIST 1 lens 2 eyecup 3 pad 4 goggle body 5 connecting member 6 connecting part 7 head strap 8 length adjuster 9 connecting bridge 10 protrusion 11 cap 12 head mannequin 13 support arm 14 elevating device 15 inclined rail 16 pool 17 water 18 water pressure Resistance measuring devices 20, 21 Goggles

Claims (5)

A water resistance measuring device for swimming goggles,
A head mannequin equipped with the goggles,
An elevating device that elevates and lowers along a slope rail having a predetermined angle above a pool having still water,
A support arm fixed to the elevating device, and means for jumping the head mannequin fixed to the support arm into a pool;
Pressure sensors are connected to the upper and lower positions of the goggles, and the goggles include means for measuring a change in water pressure over time and calculating a difference in moment applied to the goggles from each pressure sensor measurement value. Hydraulic resistance measuring device.   The goggle hydraulic resistance measuring device according to claim 1, wherein the inclination angle of the inclined rail with respect to the water surface is adjustable, and the lifting device can be fixed at an arbitrary position of the inclined rail.   A position sensor is disposed at a position where the tip forehead of the head mannequin enters the water surface and on the front side thereof, respectively, and the maximum speed of the head mannequin and the water entry time are measured, and the top and bottom of the goggles are measured. The goggles hydraulic resistance measuring device according to claim 1 or 2, wherein a maximum load applied to the goggles is measured by a pressure sensor at a position. Measuring a moving distance of the head mannequin for two seconds from the start of measurement, calculating a speed from the moving distance , obtaining an approximate curve of the speed, and obtaining a speed graph, an acceleration graph, and a load graph of the head mannequin. Item 4. The goggle hydraulic resistance measuring device according to any one of Items 1 to 3.   The change in the pressure of the goggles is converted as a load (N) by multiplying the surface area of the pressure sensor, and using this load, an impulse between the time of entry into the water surface and the time of the maximum load in water is determined. The goggle hydraulic resistance measuring apparatus according to any one of claims 1 to 4, wherein an impact force at the time of landing is obtained from the following.