3results about How to "Avoid abnormal vibration" patented technology

This application provides a method, apparatus, device, vehicle refrigerator, and vehicle for controlling a vehicle refrigerator compressor, relating to the field of vehicle technology. The method includes acquiring the resonant speed of the vehicle refrigerator compressor and a pre-constructed set of operating speeds; the pre-constructed set of operating speeds includes compressor speeds corresponding to different vibration and noise performance characteristics; selecting a target operating speed from the pre-constructed set of operating speeds that avoids the resonant speed, and controlling the compressor to operate at the target operating speed. This application alleviates the limitations of traditional methods that solely limit speed in pursuit of NVH (Noise, Vibration, and Harshness), achieving a dynamic balance between NVH performance and cooling efficiency in vehicle refrigerators, effectively resolving the contradiction between slow cooling and vibration noise, and significantly improving user experience and overall vehicle comfort.

This utility model relates to a display device, which includes a display panel, a back plate, a rear shell, and a speaker assembly. The speaker assembly includes a speaker housing, at least one first speaker, and at least one second speaker. The diaphragm of the first speaker is exposed on the back of the speaker housing and faces the rear shell; the diaphragm of the second speaker is exposed on the front of the speaker housing and faces the back plate. A venting channel is provided on the front of the speaker housing, and the diaphragm of the second speaker is disposed within the venting channel. At least one end of the venting channel extends to the side edge of the speaker housing and forms an outlet. The diaphragms of the first and second speakers exert opposite forces on the speaker housing, thereby reducing the resultant force of the diaphragm vibration on the speaker housing and weakening or eliminating the vibration of the speaker assembly. Abnormal air pressure generated by the vibration of the second speaker can be discharged through the outlet of the venting channel, eliminating abnormal vibration of the display device.

This invention relates to the field of cementing equipment technology in oil extraction, specifically a casing centralizer for oil extraction cementing. It includes two identical centralizer mounting bases, a first centralizer mounting base and a second centralizer mounting base. Multiple inner constraint spring plates are distributed between the two bases and combined to form a cylindrical frame. Outer main spring plates are correspondingly located on the outer sides of the inner constraint spring plates. The centralizer also includes a curvature adjustment mechanism and wellbore inner diameter detection and control equipment. The curvature adjustment mechanism drives a sliding column via a hydraulic system, pulling a curvature adjustment rope to adjust the distance between the outer main spring plates and the inner constraint spring plates. This centralizer can dynamically adapt to the outer diameter according to the wellbore inner diameter, providing precise and stable adjustment. It reduces downhole movement friction and component wear, ensuring the casing remains centered, effectively improving cementing construction quality and equipment operational reliability, and adapting to complex and harsh downhole conditions.