46results about How to "Avoid thermal convection" patented technology

An illumination lamp comprises a lamp body, a light-emitting module, a power supply module, and a circuit module. The lamp body defines an inner space. The partitioning unit is disposed in the lamp body for dividing the inner space into a first space for receiving the power supply module, and a second space for receiving the circuit module. Due to the presence of the partitioning unit, thermal convection between the first and second spaces is prevented to reduce adverse influence of a high temperature of the circuit module on the power supply module.

The invention discloses a heat insulation cold closet. According to the heat insulation cold closet, due to the fact that a vacuum heat insulation panel layer and a rigid polyurethane layer are arranged in a polyurethane foamed plastic layer to form a composite head insulation structure, the thickness of the heat insulation cold closet is reduced so that the effective volume of a heat insulation closet in the same shape can be greatly increased; furthermore, the coefficient of heat insulation of the heat insulation cold closet is smaller than or equal to 0.004W / mK, heat radiation, heat conduction and heat convection between the interior of the closet body and the outside environment can be effectively prevented, and the heat insulation closet can guarantee that the interior temperature is controlled below 2-8 DEG C for more than 120 hours. The heat insulation cold closet is mainly used for cold storage and refrigeration during transportation and storage of medicine such as vaccine, insulin, blood products, biological products and reagents.

The invention provides a light fixture for illuminating a sign. The light fixture has a lamp and one or more reflectors to provide for substantially uniform illumination of a sign with a minimum number of light fixtures. One or more of the reflectors of some embodiments can formed from a material having predetermined pattern for reflecting and transmitting light from the lamp. For example, the reflectors can be made from a neutral density polymeric material consisting of a translucent or substantially transparent polymeric substrate with a pattern of reflective media disposed on or within the substrate. In some embodiments, one of the reflectors can be a specular reflector. Some embodiments of the light fixture can also include a thermal shield to at least partially prevent thermal convection along a portion of the lamp.

The invention relates to a heat-insulated refrigerator for medical medicine, comprising a box body with an opening, and a cover body sealingly fitted with the opening; the box body is sequentially composed of a hard polyurethane layer and a vacuum insulation board layer , foamed polyurethane board and shell. In the heat-insulating refrigerated box of the present invention, since the vacuum insulation board layer and the rigid polyurethane layer are arranged in the polyurethane foam plastic layer to form a composite heat-insulating structure, not only the thickness of the heat-insulated refrigerated box is reduced, but also the same appearance The effective volume of the insulation box is greatly improved, and its thermal insulation coefficient is less than or equal to 0.004W / mK, which can effectively prevent heat radiation, heat conduction and heat convection between the inside of the box and the external environment. The heat insulation box can ensure that the temperature inside the box is within At 2-8°C, the duration is more than 120 hours; the insulated refrigerator of the present invention is mainly used for refrigeration and freezing of vaccines, insulin, blood products, biological products, reagents and other medicines during transportation and storage.

A preparation method of a polyurethane resin including the following steps is provided. A liquid polyamine compound is placed in a continuous reaction system, and the liquid polyamine compound is circulated in the continuous reaction system. A solid bis(cyclic carbonate) and a solid catalyst are placed in the continuous reaction system to mix the solid bis(cyclic carbonate), solid catalyst, and liquid polyamine compound to form a heterogeneous mixture. The heterogeneous mixture is heated in the continuous reaction system in a microwave manner, such that the heterogeneous mixture reacts to form a polyurethane resin.

The invention provides a small-rotation-angle transmission device with a gap eliminating mechanism, which can be taken as a small-rotation-angle transmission system with a small rotation stroke, such as a declination axis. The small-rotation-angle transmission device comprises a transmission case and a rotating shaft, wherein the rotating shaft is externally provided with a shaft sleeve which is fixedly connected with the transmission case; a transmission shaft is provided with a pre-stretched spring; one end of the spring is fixed on the end face of the transmission shaft, and the other end of the spring is fixed on the shaft sleeve; when the rotating shaft rotates to any angle, rotating torque output from the spring is same. The small-rotation-angle transmission device provided by the invention adopts the spring to output the constant torque so as to implement transmission gap elimination, so that a motor and a drive circuit are omitted, the device cost and power consumption are saved, the motor is prevented from heating, and imaging quality is prevented form being reduced by thermal convection. The small-rotation-angle transmission device is simple in structure, reliable in performance, and not easy to be damaged.

The invention discloses an aluminum alloy laminar flow distribution plane solidification casting device and a casting method thereof, and belongs to the technical field of aluminum alloy ingot blank casting. The device comprises a support. A translation flow distribution mechanism capable of moving horizontally is arranged on the upper portion of the support. A flow control mechanism is arranged at an outlet of the translation flow distribution mechanism. A casting tank is arranged below the translation flow distribution mechanism. A water spraying system and a cooling plate system are arranged below the casting tank. The method includes the steps that the cooling plate system rises into the casting tank, and molten aluminum alloy enters a flow distribution groove and then enters a guide rod sleeve; a second motor is started to control flow of the molten aluminum alloy; a first motor is started, a movable plate drives the flow distribution groove to move horizontally, and the molten aluminum alloy flows to a cooling plate upper plate body in a laminar mode; when an aluminum alloy solidification layer can be supported, a cooling plate oil cylinder is started, and thus the cooling plate system descends; then the water spraying system is pushed in, and sprayed water is cooled; the descending speed of a main oil cylinder is controlled until casting reaches a preset thickness; and after all the cooling is completed, water spraying is stopped, the water spraying system is extracted, ingot castings are taken out, and accordingly casting is completed.