摘要:
In an energy-saving evaluation apparatus for evaluating energy conservation for a machine that is to be operated by a user, the energy-saving evaluation apparatus includes: a detection unit that includes a monitor device for measuring a running state of the machine, detects an operating state of the machine operated by the user through measuring the running state of the machine by the monitor device; and an evaluation unit that performs an energy-saving evaluation based on the detected operating state of the machine.
摘要:
In an energy-saving evaluation apparatus for evaluating energy conservation for a machine that is to be operated by a user, the energy-saving evaluation apparatus includes: a detection unit that includes a monitor device for measuring a running state of the machine, detects an operating state of the machine operated by the user through measuring the running state of the machine by the monitor device; and an evaluation unit that performs an energy-saving evaluation based on the detected operating state of the machine.
摘要:
A sound absorbing structure is constituted of a vibration plate and a rear air layer and is installed in a luggage compartment or trunk which is separated from a cabin in a vehicle. Sound waves entering into the luggage compartment drive the vibration plate to vibrate so that acoustic energy is converted into mechanical energy and is consumed by way of vibration of the vibration plate. By appropriately setting parameters and dimensions, the sound absorbing structure efficiently absorbs low-frequency sound such as road noise occurring due to friction of wheels of the vehicle traveling on a road.
摘要:
A sound absorbing structure is constituted of a housing having a hollow portion and an opening and a vibration member composed of a board or diaphragm. The vibration member is a square-shaped material having elasticity composed of a synthetic resin and is bonded to the opening of the housing, thus forming an air layer closed inside the sound absorbing structure by the housing and the vibration member. In the sound absorbing structure, when the lateral/longitudinal dimensions of the air layer and characteristics of the vibration member (e.g. a Young's modulus, thickness, and Poisson's ratio) are set such that the fundamental frequency of a vibration occurring in a bending system falls within 5% and 65% of the resonance frequency of a spring-mass system, a vibration mode having a large amplitude occurs in a frequency band lower than the resonance frequency of the spring-mass system, this improving the sound absorption coefficient.
摘要:
A sound absorber is formed by covering the opening of a housing with a vibration member having a flat shape or a film shape so as to define an air layer therebetween. The sound absorber is attached to the wall of a room such that the vibration member is positioned opposite to the wall with a prescribed space therebetween. Sound generated in the room particularly in low frequencies enters into the space between the vibration member and the wall so as to cause vibration of the vibration member due to the pressure difference between the sound pressure applied to the space and the internal pressure of the air layer, thus consuming energy of sound waves. Thus, it is possible to efficiently absorb low-frequency sound with a reduced thickness of the air layer.
摘要:
In the floor base panel (40), an area on the support board (33) of the vibration proof support leg (30) is formed solid, and in the other area, a plurality of cavities (41) extending parallel to the floor surface are formed. Thereby, because the vibration energy propagated from the impact point of the floor base panel (40) is reflected on the boundary between the cavity formation area and the solid area, and repeatedly passes the cavity formation area, it is attenuated in a short time, and the vibration energy or sound energy transmitted to a slab (20) can be reduced.
摘要:
An electronic keyboard musical instrument, including: a keyboard; a musical-sound signal generating circuit; at least one speaker for emitting sound in accordance with a generated signal; a speaker accommodating body accommodating the speaker in its inner space; and at least one resonator disposed in the accommodating body, wherein the accommodating body includes a sound emission path by which the sound emitted by the speaker is introduced to an exterior of the accommodating body via the inner space for sound propagation to the exterior, a control point of the resonator is located at a position corresponding to an antinode of a sound pressure in a natural vibration mode at a specific frequency generated in the inner space by driving of the speaker, and the resonator resonates at the specific frequency for adjusting the sound pressure, whereby the sound is emitted from the sound emission path to the exterior.
摘要:
An acoustic resonator adaptable to a sound chamber is designed to decrease a sound pressure while increasing a particle velocity of medium particles in a low frequency range without increasing the overall size thereof. The acoustic resonator is constituted of a pipe member having one opening end and a resistance member embracing a high resistance region and a low resistance region. The resistance member is inserted into the pipe member such that one end thereof matches the opening end of the pipe member while the other end thereof is disposed at a predetermined position inside a hollow cavity of the pipe member. The high resistance region embraces an antinode region of the particle velocity distribution with respect to a standing wave occurred in the hollow cavity at a resonance frequency, thus causing an acoustic phenomenon decreasing the resonance frequency compared to a single unit of the pipe member.
摘要:
A sound absorber is formed by covering the opening of a housing with a vibration member having a flat shape or a film shape so as to define an air layer therebetween. The sound absorber is attached to the wall of a room such that the vibration member is positioned opposite to the wall with a prescribed space therebetween. Sound generated in the room particularly in low frequencies enters into the space between the vibration member and the wall so as to cause vibration of the vibration member due to the pressure difference between the sound pressure applied to the space and the internal pressure of the air layer, thus consuming energy of sound waves. Thus, it is possible to efficiently absorb low-frequency sound with a reduced thickness of the air layer.
摘要:
An electronic keyboard musical instrument, including: a keyboard; a musical-sound signal generating circuit; at least one speaker for emitting sound in accordance with a generated signal; a speaker accommodating body accommodating the speaker in its inner space; and at least one resonator disposed in the accommodating body, wherein the accommodating body includes a sound emission path by which the sound emitted by the speaker is introduced to an exterior of the accommodating body via the inner space for sound propagation to the exterior, a control point of the resonator is located at a position corresponding to an antinode of a sound pressure in a natural vibration mode at a specific frequency generated in the inner space by driving of the speaker, and the resonator resonates at the specific frequency for adjusting the sound pressure, whereby the sound is emitted from the sound emission path to the exterior.