JPH0585821U - Helmet - Google Patents

Abstract

(57) [Summary] [Purpose] To obtain a helmet that can display the history of impacts received and warn of the possibility of security defects inside its structure. A helmet having impact sensors 21, 22, 23 on a main body 10 and a peak hold voltmeter 30 for displaying impact information received by them as impact history.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a helmet used while riding a motorcycle or an automobile, or at the site of construction or disaster, and particularly to a helmet whose impact history can be visually recognized.

[0002]

[Prior Art]

 Conventionally, a helmet is worn to protect a person's head from accidents that occur while riding a motorcycle or car, working at a factory or a construction site, or at a disaster site. Such helmets are molded from FRP, a composite material such as fiber reinforced plastic, and are designed and manufactured to have sufficient strength to protect the wearer's head from impact. However, such strength is possessed when the helmet is not subjected to any impact, and even if it cannot be visually recognized once it has been impacted, the internal structure of the helmet will be distorted and When received, it may not have sufficient strength to protect it. In fact, as it is said that a helmet once dropped from a height of 1 meter onto a hard surface such as a concrete floor should not be used, if it has impact strain inside the structure, it cannot be visually recognized. Even if it exists, it is easily damaged by a comparatively mild impact, resulting in a serious safety hazard.

[0003]

[Problems to be solved by the device]

 Such a conventional helmet has a problem that a safety defect inside the structure due to impact strain cannot be recognized unless a special device such as an ultrasonic flaw detector is used. Therefore, in order to confirm the safety of the helmet before wearing it, there has been a demand for a helmet that can display the history of impact received by itself and warn of the possibility of a security defect.

[0004]

Means for Solving the Problems Such problems can be solved by using a helmet having a means for displaying impact history. In the above, it is preferable that the impact history display unit includes an impact sensor unit and a history display unit. In the above, the impact sensor unit is rigidly attached to the object to be measured, the film-shaped piezoelectric body fixed to the measurement surface perpendicular to the sensing axis of the base, and the inertia sensor attached to the film-shaped piezoelectric body. It has a load body consisting of a rigid body that acts as a mass, and the planar shape of the film-shaped piezoelectric body is point symmetric with the sensing axis as the center of symmetry in the plane parallel to the measurement plane. The plane shape of the surface in contact with the film-shaped piezoelectric body is point-symmetrical with the sensing axis as the center of symmetry, and when crossing through the sensing axis and innumerable planes perpendicular to the measurement surface, the sensing axes are It is preferable that it is made to be line-symmetrical with the axis of symmetry as.

Since the helmet of the present invention is provided with a means for displaying the history of the impact received by the helmet (hereinafter referred to as an impact history display means), the helmet may cause a security defect inside the structure. When an impact that exceeds a certain safety limit value is received, the impact history is displayed. Therefore, whether or not the helmet has already been subjected to a dangerous degree of impact can be easily visually recognized at the site of use, and it is possible to warn of the possibility of a security defect that poses a serious safety obstacle.

Next, each element constituting the helmet of this invention will be described. The material and shape of the helmet body of the present invention are not particularly limited, but it can be manufactured by using a material conventionally used for this purpose such as FRP and molding it into a shape satisfying the function according to the purpose. it can.

The impact history display means included in the helmet of the present invention comprises an impact sensor section and a history display section. The shock sensor unit is a device that receives a shock and outputs the shock information through some medium. Although such a device is not particularly limited, a device generally known as an acceleration sensor or a vibration sensor can be used. An example of such an acceleration sensor or vibration sensor is one in which a load body composed of a rigid body acting as an inertial mass is arranged with a gap from a pedestal rigidly attached to the object to be measured. it can. If it is subdivided further, for example, the relative displacement of the gap between the pedestal and the load body when it is subjected to acceleration is output as a change in solid pressure, or is output as a change in fluid pressure. There are those which output as a change in current and voltage by a piezoelectric sensitive magnetic circuit, and those which output as a change in electrostatic pressure like a piezoelectric element, and any of them can be used as an impact sensor portion of the helmet of the present invention. As an example of a particularly preferable impact sensor unit, a pedestal rigidly attached to an object to be measured, a film-shaped piezoelectric body fixed to a measurement surface perpendicular to the sensing axis of the pedestal, and a film-shaped piezoelectric body fixed to the film-shaped piezoelectric body. , A load element composed of a rigid body that acts as an inertial mass, and the planar shape of the film-shaped piezoelectric body is a point pair with the sensing axis as the center of symmetry in a plane parallel to the measurement surface. The plane shape of the surface in contact with the film-like piezoelectric body is point-symmetrical with the sensing axis as the center of symmetry, and when crossing through the sensing axis in a myriad of planes perpendicular to the measurement surface, An example is a piezoelectric acceleration sensor that is line-symmetrical with the sensing axis as the axis of symmetry.

The history display unit includes a device that converts the impact information provided by the impact sensor unit into visual information and holds the visual information. As such a history display section, various ones can be used according to the form of information provided from the impact sensor section. For example, for impact information output as a change in solid pressure, when an acceleration pressure above a certain value is applied to the gap between the load and the pedestal, for example, a box made of fragile plastic, There may be mentioned a display device which itself is destroyed. In this case, if the box is destroyed, the impact history can be visually confirmed. For example, for a shock information output as a change in fluid pressure, a history display section composed of two liquids which are color-reactive and color-changing and are arranged with a thin film interposed therebetween can be cited. When a pressure higher than a certain value is applied to one of the two liquids, the thin film is ruptured by the fluid pressure or the pin that is operated by the fluid pressure, and the two liquids mix and react, causing color change and color development. It is retained as a shock history. For example, for impact information output as current / voltage changes, a history display unit including a current / voltmeter having a peak hold function can be cited. Further, for example, for impact information output as a voltage change, an electrochromic display element that changes color by application of a voltage of a certain value or more and holds the color, for example, a history display section including a liquid crystal element can be used.

As the impact history display means included in the helmet of the present invention, it is possible to use other means than the above-mentioned load body as the inertial mass. An example thereof is a pressure-sensitive color-developing coating film that covers the entire outer surface of the helmet. In this case, when the helmet receives an impact, the microcapsules distributed in the coating film are destroyed, and the leuco dye in the helmet reacts with the color-forming agent in the vehicle to develop color, and the coloring causes impact history. It is held at the site where it was received.

The helmet of the present invention is constructed by disposing one or more sets of impact history display means including the impact sensor section and the history display section as described above on the body thereof. In this case, the impact history display means may be a combination of a plurality of impact sensor sections and one history display section. When the impact history display means composed of one history display unit is used for a plurality of impact sensor units, each impact information provided by the plurality of impact sensor units may be transmitted in parallel to the history display unit. However, a means for transmitting the resultant force of the impact detected by each impact sensor to the history display section may be used. Such means comprises, for example, a well-known arithmetic circuit configuration for synthetically calculating the fluid pressure and the current / voltage values output by the respective impact sensors.

The parts and the number of parts on the helmet where the impact sensor part is arranged are determined by the shape and structure of the helmet body, the sensitivity directivity of the adopted impact sensor part, and the like. It is preferable to select which parts of Helmet will be displayed when the safety limit value is exceeded no matter which part of the helmet is hit. The impact sensor part, which has a structure that uses the load body as the inertial mass, generally has sensitivity directivity. Therefore, when using multiple such impact sensor parts, arrange them on the surface of the helmet so that the extension lines of the sensing axis that maximize the sensitivity are orthogonal to each other, and The impact value output by the impact sensor when the impact of the safety limit value is applied to the point where a straight line with an angle of 45 degrees to each sensing axis intersects with the outer surface of the Hermet is used as the safety limit value in the history display section. If shown, even if any part of the helmet body receives an impact exceeding the safety limit, it can be displayed in the history display section as an impact history to be warned. The minimum number of impact sensor units that satisfy this condition is three. On the other hand, if the history display unit is integrated with the impact sensor unit, the location and number of the history display unit are dependent on the impact sensor unit. If they are not integrated, it is sufficient to determine the parts and number that are easy to see and whose display function is not destroyed. In this case, a shock information transmission means is provided by connecting the shock sensor unit and the history display unit. If the information medium is a fluid, a plastic pipe or a copper pipe is used as the transmitting means, and if it is electric, a lead wire is used.

[0012]

【Concrete example】

 Next, a specific example of the present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective view showing a specific example of the helmet of the present invention. The arrow in the figure indicates the front of the helmet (face direction). In FIG. 1, reference numeral 10 indicates the body of the helmet. The main body 10 is integrally formed by FRP, and the head entrance 11 and the visual field hole 12 are opened. A windshield (not shown) is attached to the visual field hole 12 to secure the field of view of the wearer. The integrally molded main body 10 continuously forms a crown 13, a occipital region 14, and temporal regions 15 and 15 '. The top portion 13, the back portion 14, and the side portion 15 on one side are provided with recesses for accommodating an impact sensor described below.

Impact sensors 21, 22 and 23 are respectively inserted in the recesses provided in the crown 13, the occipital region 14, and the temporal region 15 on one side, and each pedestal has an epoxy adhesive. It is rigidly joined to the body 10. These impact sensors are of the same type, and are piezoelectric impact sensors of 10 mm square and 5 mm thick. They are arranged so that their sensitivity axes are orthogonal to each other inside the main body 10. The impact sensors 21, 22 and 23 have leads 41, 42 and 43 for outputting impact information, respectively. Each lead wire extends through the shell from the bottom of the recess in which each impact sensor of the main body 10 is inserted and is drawn out to the inside of the main body 10. The lead wires 41, 42 and 43 drawn out from the respective impact sensors to the inside of the main body 10 are wired along the inner surface of the main body 10, respectively, inside the main body portion where the peak hold voltmeter 30 described below is arranged. Collected, penetrating the shell of the main body 10 and connected to respective input terminals (not shown) of the corresponding peak hold voltmeter 30. A peak hold voltmeter 30 is joined to the outer surface of the shell near the head opening 11 below the temporal region 15 'on the side opposite to the site where the impact sensor 23 is provided. This peak hold voltmeter 30 is an indicator 31 consisting of a series of liquid crystal segment rows arranged on the scale plate and capable of displaying and holding the peak voltage value as a bar graph, and a scale 31 across the liquid crystal segment rows on the scale plate. It has a mark 32 representing the drawn warning area. Further, although not shown, the peak hold voltmeter 30 has a power supply battery, a holder for the power supply battery, an input terminal for an electric signal provided from each impact sensor, and a signal processing device for processing the input signal and outputting it to the indicator 31. is doing.

Next, the operation of this helmet will be described. When the main body 10 receives a strong shock due to the helmet falling on a hard floor or colliding with a hard object, the shock is sensed by one of the shock sensors 21, 22 or 23. Since these shock sensors are arranged so that their sensitivity axes are orthogonal to each other, even if a shock is applied to any part of the outer surface of the main body 10, one to three shock sensors sense it. . The impact sensor that receives an impact generates a charge corresponding to the impact force received by the piezoelectric effect and outputs it as a voltage. This output is individually input to the input terminal of the peak hold voltmeter 30 through the lead wires 41, 42 or 43. Each input voltage is sent to the signal processing device in the peak hold voltmeter 30, where it is arithmetically processed to be combined into one voltage value and compared with the past peak voltage value (history value). Only when it is higher, the indicator 31 indicates a new peak voltage value. Then, if the peak voltage value indicated by the indicator 31 falls within the warning area of the mark 32, it means that the history of the impact of the helmet over the regulation is displayed.

Next, a test example of the helmet having the configuration of the above specific example will be shown. As the impact sensors 21, 22, and 23, those which generate an output of 4 mV per impact 1 G were used. As the peak hold voltmeter 30, a marker 32 for warning is attached to a region instructing output of 500 G (2000 mV) or more. 20 such helmets were prepared. As a comparative example, 20 helmets of the same shape having no impact history display means were prepared. The helmets of the test example and the comparative example were dropped onto a concrete surface from a height of 1 m. The collision area with the helmet floor was not constant. The coating was peeled off partly in all helmets, and no cracks or the like were observed from the outside. However, the peak hold voltmeters of the helmets of the specific examples all showed peak values corresponding to 500 to 1,000 G, indicating that the degree of impact was in the warning area. When all the helmets of Examples and Comparative Examples were inspected with an ultrasonic flaw detector, internal cracks were found in 10 or more helmets each.

[0016]

【effect】

 Since the helmet of the present invention has a means for displaying the impact history, it has the effect of displaying the history of the impact received and warning of the possibility that a security defect exists inside the structure.

[Brief description of drawings]

FIG. 1 is a perspective view showing a specific example of a helmet of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Main body, 11 ... Head entrance, 12 ... Visual field hole, 13 ... Top of head, 14 ... Occipital region, 15, 15 '... Temporal region 21, 21,
2, 23 ... Impact sensor, 30 ... Peak hold voltmeter,
31 ... Pointing tool, 32 ... Marker, 41, 42, 43 ... Lead wire.

Claims (3)

[Scope of utility model registration request] 1. A helmet comprising an impact history display means. 2. The helmet according to claim 1, wherein the impact history display means comprises an impact sensor section and a history display section. 3. The pedestal according to claim 2, wherein the impact sensor unit is rigidly attached to the object to be measured, a film-shaped piezoelectric body fixed to a measurement surface perpendicular to the sensing axis of the pedestal, and the film-shaped piezoelectric body. Having a load body made of a rigid body that is fixed on the body and acts as an inertial mass, the planar shape of the film-shaped piezoelectric body is point symmetric with the sensing axis as the center of symmetry in a plane parallel to the measurement surface, The load body, when the plane shape of the surface in contact with the film-shaped piezoelectric body is point-symmetrical with the sensing axis as the center of symmetry, and passes through the sensing axis, and is sectioned by a myriad of planes perpendicular to the measurement surface, A helmet characterized in that it has line symmetry with the sensing axis as the axis of symmetry for all cross sections.