JP2017003568A - Goggle hydraulic pressure resistance measurement device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a goggle hydraulic pressure resistance measurement device subjected to a strong water pressure at the time of jump-in.SOLUTION: A goggle hydraulic pressure resistance measurement device includes: a head mannequin (12) on which a goggle (20) for swimming is mounted; a lifting device (14) that ascends and descends along an inclined rail (15) having a prescribed angle at the upper part of a pool (16) having standing water (17); a support arm (13) fixed onto the lifting device (14); means for making the head mannequin (12) fixed onto the support arm (13) jump into the pool (16); and means for measuring a change in water pressure over time by a pressure sensor connected at a position above and below the goggle (20) to calculate difference in moment applied to the goggle from the measurement value of each pressure sensor.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a hydraulic resistance measuring device for goggles. More particularly, the present invention relates to a hydraulic resistance measuring device for swimming goggles suitable for swimming.

  The swimming goggles are generally composed of an eyecup lens, a goggle body including a pad integrated at the lower part of the eyecup lens, and a belt for attaching the goggle body to the head of the human body. Patent Document 1 proposes a goggle in which the lower surface is made longer than the upper surface of the pad so that water leakage does not occur even when a strong water pressure is applied, such as when diving. Patent Document 2 proposes goggles in which a connecting member is fixed to a side portion of an eye cup and a head strap is connected to the connecting member in order to improve the wearing feeling. Patent Document 3 proposes to provide a convex strip having a groove on the side surface of the eye cup in order to reduce fluid resistance.

JP 2011-083539 A JP 2012-070794 A JP2013-104469A

  However, the conventional goggles have a problem in that they are misaligned or disengaged when a strong water pressure is applied at the time of diving. In order to solve this problem, a hydraulic resistance measuring device for goggles is required. However, such a device has not been found so far, and development from the industry has been requested.

  In order to solve the above-described conventional problems, the present invention provides a hydraulic resistance measuring device for goggles in which strong water pressure is applied when diving.

  A hydraulic resistance measuring device for goggles according to the present invention is a hydraulic resistance measuring device for swimming goggles, on a head mannequin fitted with the goggles and an inclined rail having a predetermined angle above a pool having stationary water. A lifting device that moves up and down along, a support arm fixed to the lifting device, a means for jumping the head mannequin fixed to the support arm into the pool, and a pressure sensor connected above and below the goggles And 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.

  The hydraulic resistance measuring device for goggles according to the present invention includes a lifting device that moves up and down along an inclined rail having a predetermined angle above a pool having static water, a support arm fixed to the lifting device, and the support. Means for jumping the head mannequin fixed to the arm into the pool, and pressure sensors are connected to the upper and lower positions of the goggles, and the change in water pressure is measured over time, and the pressure sensor measurement values are added to the goggles. By including a means for calculating the difference in moments, it is possible to accurately measure the hydraulic resistance of goggles to which strong water pressure is applied when diving.

FIG. 1 is a schematic perspective view of an 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. 3 is a schematic cross-sectional view taken along the line II of FIG. FIG. 4 is a schematic side view of a hydraulic resistance measuring device according to an embodiment of the present invention. FIG. 5 is a front photograph showing the positional relationship of the pressure sensors arranged above and below the goggles of the head mannequin. FIG. 6 is a front photograph of the goggle worn on the head mannequin and covered with a cap. FIG. 7 is a graph showing a difference in water pressure moment applied to the top and bottom of the goggles during the diving experiment of Example 1. FIG. 8 is a graph showing a difference in moment of water pressure applied to the upper and lower sides of the goggles in the diving experiment of Example 2. FIG. 9 is a graph showing the difference in water pressure moment applied to the top and bottom of the goggles of Example 3. FIG. 10 is a graph showing the difference in water pressure moment applied to the top and bottom of the goggles of Example 4. FIG. 11 is a graph showing the difference in moments of water pressure applied to the top and bottom of the goggles of Example 5. FIG. 12 is a graph showing changes in speed and load in the measurement time t = 0 to 1.5 seconds in Example 1 and Reference Example 1. FIG. 13 is a graph obtained by calculating the speed after moving average calculation of the moving distance of the diving experiment of one embodiment of the present invention. FIG. 14 is a graph of the speed calculated from the approximate curve. FIG. 15 is a graph of acceleration calculated from the approximate curve. FIG. 16 is a graph of the load calculated from the approximate curve.

  The goggle hydraulic resistance measuring device of the present invention develops a goggle that does not have such problems by analyzing the phenomenon that the goggles shift or come off or lie down from underneath when strong water pressure is applied when diving, etc. It was completed for the purpose of doing. The apparatus includes an elevating device that moves up and down along an inclined rail having a predetermined angle above a pool having stationary water, a support arm fixed to the elevating device, and a head fixed to the support arm. Means for jumping the mannequin into the pool, and pressure sensors connected to the upper and lower positions of the goggles, measuring changes in water pressure over time, and calculating the difference in moments applied to the goggles from each pressure sensor measurement value including.

  The inclination angle 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 surface entry speed of the head mannequin is 2.2 m / second to 6 Adjust the height of the head mannequin from the water surface to 0.0 m / sec. Inclination angle and water surface entry speed are obtained from general data of swimming.

  This will be described below with reference to the drawings. In the following drawings, the same symbols indicate the same items. FIG. 1 is a schematic perspective view of an embodiment of goggles used in the present invention. The goggle 20 includes a goggle main body 4 including an eye cup 2 in which the lens 1 is integrally formed, and a pad 3 integrated under the eye cup 2, and a head for attaching the goggle main body 4 to the head of a human body. A strap 7 and a connecting member 5 for connecting the goggle body 4 and the head strap 7 are included. A slit is formed at the front end of the connecting member 5 in the vertical direction, and the connecting member 5 and the head strap 7 are connected to the slit through the head strap 7. 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 eye cups 2 are connected by a connecting bridge 9.

  In this goggles, the connecting member 5 is formed of a rubber belt, and this connecting member 5 covers the surface of the pad 3 and 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 works. Therefore, even when strong water pressure is applied, the goggle body is difficult to slip or come off the face.

  In addition, the goggles of the present embodiment form a plurality of protrusions 10 in a horizontal row on the upper side surface of the eye cup 2. Thereby, water flow resistance can further be reduced. As the protrusions, four hemispherical protrusions having a radius of 1.2 mm were arranged at intervals of 2 mm, and arranged in a horizontal row on the inclined portion of the upper side surface of the eye cup.

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

3 is a schematic cross-sectional view taken along the line II of FIG. The eye cup 2 and the pad 3 are integrally molded, and the connecting member 5 of the rubber belt is fitted in a groove formed on the outer surface between the lower part of the eye cup 2 and the pad. In FIG. 3, θ ₁ is an angle between the surface of the lens 1 and the outer inclined portion of the eye cup 2, and θ ₂ is an angle between a parallel line of 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 works. Therefore, even when strong water pressure is applied, the goggle body is difficult to slip or come off the face.

  FIG. 4 is a schematic side view of a hydraulic resistance measurement test of one embodiment of the present invention. This hydraulic resistance measuring device 18 is provided above a pool 16 containing water 17 (static water), a support arm 13 fixed to an elevating device 14 that moves up and down along an inclined rail 15, and fixed to the support arm 13. This is a device for jumping the head mannequin 12 into the pool 16. The goggles 20 are attached to the head mannequin 12, covered with the cap 11, and jumped into the water surface. The measurement dimensions of the pool are a length of 6.0 m, a width of 2.0 m, and a water depth of 1.0 m. 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 with an interval of 32 mm so that changes in water pressure can be measured over time. A difference in moment applied to the goggles 20 can be calculated from each pressure sensor measurement value. FIG. 6 is a front view photo of the goggle attached to the head mannequin and covered with a cap. The inclination angle between the inclined rail and the water surface can be adjusted, and the elevating device can be fixed at an arbitrary position of the inclined rail. As an example, the inclination angle of the inclined rail 15 with respect to the water surface was 40 °, and the water entered the water surface at a height of 900 mm from the water surface, and the water surface entry speed was about 2.5 m / second. The analysis followed the following procedure.

A 1st position sensor is arrange | positioned in the position of 433 mm in height from a water surface, and time measurement is started from the time of the front-end | tip (forehead part) of the head mannequin 12 passing. A 2nd position sensor is arrange | positioned in a water surface contact position, and measures the time when the front-end | tip (forehead part) of the head mannequin 12 contacted the water surface. Thereby, the time from the start of the measurement time to the entry of the water surface is known. The video of the head mannequin 12 when it entered the water surface was shot as a high-speed video (300 fps) using a digital camera (CASIO EX-F1). The measurement conditions were sampling frequency: 1000 Hz, measurement time: 2 sec, A / D conversion resolution: 14 bits, and processed using a personal computer. Each data was acquired as a voltage value and converted into a physical quantity by post-processing. In summary, the measurement items are as follows.
(1) Position of head mannequin 12 (2) Pressure due to wearing goggles (3) Time from measurement time start to water surface entry (4) Movie of head mannequin 12 water surface entry

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 after moving average calculation (5 points) in the measurement result, 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 weight of each specimen in the measurement time (2 seconds) (FIGS. 14 to 16).
(3) The change in pressure when the goggles are attached is converted to 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 (2) above, the maximum load value 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 “water surface entry time and the maximum load time in water” using the load obtained in (3). Further, the difference in 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 shift of the goggles when the load is maximum in water is evaluated.

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

In this test, _two impulses on the sensor and below the sensor from the time t _{1 when the} water surface enters to the time t _{2 when} the load is maximum in water are obtained, and the sum I _total is shown as a result. If the sampling time is Δt (= 0.001), the impulse on the sensor is I _t , and the impulse on the sensor is I _b , the following _equations (2) and (3) are obtained.

Here, F _t and F _b are forces acting on the sensor and below the sensor. The sum I _total of the two _impulses is as follows.
I _total = I _t + I _b
Next, the moment was set around the center position where the sensor was connected to the sensor by a straight line. When the moment arm length is L (= 0.016) and the moments around the center position are M _t and M _b , respectively, the following results.
M _t = F _t × L
M _b = F _b × L
Here, the direction in which the goggles push the face is positive. Next, the moment difference ΔM is calculated by the following calculation based on the moment on the sensor.
ΔM = M _t −M _b

  The present invention will be specifically described below 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 created. The lens 1, the eye cup 2 and the pad 3 were integrally formed of polycarbonate resin, the head strap 7 was formed of silicone rubber, and the connecting member 5 of the rubber belt was formed of polyurethane elastomer. The rubber belt connecting member 5 was fitted in a groove formed on the outer surface between the lower portion of the eye cup 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 eye cup 2. As the protrusions 10, four hemispherical protrusions having a diameter of 1.2 mm were arranged at intervals of 2 mm, and arranged in a horizontal row on the inclined portion of the upper side surface of the eye cup 2.
The goggles 20 thus obtained were attached to the head mannequin 12 as shown in FIG. 4, covered with the cap 11, and the hydraulic resistance measurement test shown in FIG. 4 was performed. The number of measurements was 3, and the average value was calculated and the results are summarized in Table 1. FIG. 7 is a graph showing the difference in moment of water pressure applied to the upper and lower sides of the goggles during the diving experiment at the first measurement. It can be seen that there is almost no difference in the water pressure moment applied to the top and bottom of the goggles.

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

(Examples 3 to 5)
A hydraulic resistance measurement test was conducted using the product name “Accel Eye Cutter” manufactured by Mizuno Co., Ltd. as Example 3 and the product name “Accel Eye” manufactured by Mizuno Co., Ltd. as Example 4, and a commercially available product from another company as Example 5. Average value of 3). The results are summarized in Table 1. The results of the first measurement of Example 3 are shown in FIG. 9, the results of the first measurement of Example 4 are shown in FIG. 10, and the results of the first measurement of Example 5 are shown in FIG.

(Reference Example 1)
The results measured in the same manner as in Example 1 without wearing goggles are summarized in Table 1.

From Table 1 and FIGS.
(1) The difference in moment is a result of positively pressing the face on the sensor around the center between the two sensors. That is, if the moment difference is positive, the goggles will turn from the bottom, and if the moment difference is negative, the force will turn from the top. Every goggle has a positive moment difference, and the force to turn from below works. In Examples 1 and 2 of the present invention, the difference in moment when entering water is lower than in Examples 3 and 5, and the difference between the pressure moments above and below the goggles at the maximum load when entering the water surface is 1 × 10 ⁻⁶ N (N : Newton) 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 the water and then reduced, and the difference is large. In Example 4, it can be seen that a large moment force is generated in the eye cup when the water enters, and a small moment force remains thereafter. Further, in Example 5, it is understood that a large moment force is generated in the eye cup at the time of entering water, and then suddenly decreases, and the difference is large.
(3) From the average value of impulse, Example 3 and Example 5 have an impact force that pushes the face, and Example 4 has an impact force that causes goggles to come off the face. On the other hand, the impulse of Examples 1 and 2 is low and 10 × 10 ⁻⁶ Ns (N: Newton, s: second) or less. This indicates that the impact force at the time of entering the water surface is small, is not easily displaced, and is in close contact with the face.
(4) As described above, in Examples 1 and 2, almost no moment force was generated when water entered, and it was confirmed that the goggles were stably adhered to the face. It was also confirmed that the displacement was suppressed with low resistance to the water pressure.

  FIG. 12 shows changes in speed and load in the measurement time t = 0 to 1.5 seconds in Example 1 and Reference Example 1. However, the data in the figure is the result of each first measurement for the sake of clarity. Taking the measurement result of Reference Example 1 as an example, the speed becomes maximum at t = 0.109 seconds, and decreases rapidly when entering the water surface at t = 0.134 seconds. The reason why the speed becomes a negative value from around 0.9 seconds is that a force that rises on the water surface works due to the buoyancy of the head mannequin itself. The load enters the water surface and reaches a negative maximum at t = 0.368 seconds, and thereafter shows a change in which the gently negative load decreases. Although the measurement result of Example 1 was the same as that of Reference Example 1, due to the influence of wearing goggles, the speed reduction after entering the water surface was larger than that of the data of Reference Example 1, and the maximum load in water was also large.

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

DESCRIPTION OF SYMBOLS 1 Lens 2 Eyecup 3 Pad 4 Goggles main body 5 Connection member 6 Connection part 7 Head strap 8 Length adjustment tool 9 Connection bridge 10 Protrusion 11 Cap 12 Head mannequin 13 Support arm 14 Lifting device 15 Inclination rail 16 Pool 17 Water 18 Water pressure Resistance measuring device 20, 21 Goggles

Claims (5)

A hydraulic resistance measuring device for swimming goggles,
A head mannequin wearing the goggles;
A lifting device that moves up and down along an inclined rail having a predetermined angle above a pool having static water;
A support arm fixed to the lifting device, and means for jumping the head mannequin fixed to the support arm into the pool;
A pressure sensor is connected above and below the goggles, and includes means for measuring a change in water pressure with time and calculating a difference in moment applied to the goggles from each pressure sensor measurement value. Hydraulic resistance measuring device.   2. The apparatus for measuring hydraulic resistance of goggles according to claim 1, wherein an inclination angle between the inclined rail and the water surface is adjustable, and the lifting device can be fixed at an arbitrary position of the inclined rail. 3.   Position sensors are arranged at the position where the forehead portion of the head mannequin enters the water surface and the front side thereof, respectively, and the maximum speed of the head mannequin and the water surface entry time are measured, and above and below the goggles The hydraulic resistance measuring device for goggles according to claim 1 or 2, wherein a maximum load applied to the goggles is measured by a pressure sensor at a position.   Measure the moving distance of 2 seconds from the start of the measurement of the head mannequin, calculate the speed from the value after moving average calculation to this result, obtain the approximate curve of the speed, the speed graph and acceleration graph of the head mannequin The hydraulic resistance measuring device for goggles according to any one of claims 1 to 3, wherein a load graph is obtained.   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, the impulse between the water surface entry time and the maximum load time in water is obtained. The apparatus for measuring hydraulic resistance of goggles according to any one of claims 1 to 4, wherein an impact force at the time of landing is obtained from the water.