55results about How to "Guaranteed concentricity requirements" patented technology

The invention discloses an anti-adhesive shoulder fixture for improving the efficiency of an endurance test, which aims to provide a novel test fixture structure to improve the efficiency of the endurance test, prevent the adhesion and the tripping between a specimen and a fixture and between the fixture and a pull rod of a testing machine, and ensure the authenticity and the reliability of the test. The technical scheme of the anti-adhesive shoulder fixture has the following key points that: the fixture adopts a shoulder type structure to prevent the adhesion and the tripping between the specimen and the fixture and the adhesion and the tripping between the fixture and the pull rod of the testing machine; a shoulder type serial connector is designed, and two specimens are connected in series and are synchronously tested on one testing machine so as to improve test efficiency; a shoulder large pull head adopts K002 high-temperature alloy, and the shoulder fixture and the shoulder typeserial connector adopt directional high-temperature alloy DZ22 or single crystal high-temperature alloy DD3 to improve the applicable test temperature of the fixture to 1200 DEG C; and the fixture has simple operation and quick and convenient clamping, ensures the concentricity, and is applicable to different models of endurance testing machines produced by different testing machine manufacturers.

The invention discloses a method for machining an airfoil hole on a two-layer beam lining girder of an automobile frame, and the method comprises the following steps of: machining the ventral hole and airfoil hole of a dual-layer beam main girder by virtue of a panel numerical-control automatic punching machine at one step; machining the ventral hole of the dual-layer beam lining girder by virtue of the panel numerical-control automatic punching machine at one step; positioning the holes by using a ventral standard process and welding at a middle frequency; feeding the dual-layer beam main girder and the dual-layer beam lining girder into a pressure machine and carrying out punch forming; placing the dual-layer beam main girder and the dual-layer beam lining girder, which are formed by the pressure machine, on a device for machining the airfoil hole of the lining girder; and machining the airfoil hole on the lining girder by using the airfoil hole on the dual-layer beam main girder as a standard. By using the airfoil hole on the dual-layer beam main girder as the standard, the holes with equal diameter are rapidly machined. The method for machining the airfoil hole on the two-layer beam lining girder of the automobile frame disclosed by the invention has the advantages of convenience for positioning, high positioning precision and rapidness, simplicity and convenience in operation. The machined airfoil hole of the lining girder is high in precision. The requirement on the concentricity of the airfoil holes of the dual-layer beam main girder and the dual-layer beam lining girder is ensured. The method disclosed by the invention is beneficial to the sufficient riveting when the automobile frame is riveted, so that the adhering strength is high after a longitudinal beam is riveted, thus the product quality is improved.

The invention provides a CNC (computer numerical control) grinding machine and belongs to the technical field of machinery. The CNC grinding machine comprises a frame, a grinding tool and a bench movably mounted on the frame. The frame includes a conveying area and a processing area sequentially from front to rear. An incoming mechanism and a conveying mechanism are disposed in the conveying area. A spindle box and a discharging mechanism are disposed in the processing area. The discharging mechanism and the incoming mechanism are disposed on two sides of the spindle box. The conveying mechanism is disposed over the incoming mechanism and can linearly reciprocate between the incoming mechanism and the spindle box. A floating chuck is mounted on the spindle box. The frame is provided with an ejector base arranged right in front of the spindle box. The grinding tool is movably mounted right in rear of the spindle box. The spindle box is fixedly connected with the bench. The ejector base is disposed over the bench. The frame is further provided with a first drive motor and a second drive motor; the first drive motor can control the grinding tool to linearly move in the horizontal direction; the second drive motor can control the bench to linearly slide. The CNC grinding machine has the advantages of high automation level and operational convenience.

The invention discloses a multi-stage centrifugal pump and belongs to the technical field of fluid pumps. The centrifugal pump comprises a pump body, a transmission shaft is rotatably mounted in the pump body which comprises a pumping-in section, an intermediate section and a pumping-out section, the intermediate section is arranged between the pumping-in section and the pumping-out section, a plurality of impellers are fixedly mounted on the transmission shaft, guide blades corresponding to the impellers are arranged on the intermediate section, a pumping-in seal mechanism is arranged between the pumping-in section and the transmission shaft, a pumping-out seal mechanism is arranged between the pumping-out section and the transmission section, an air filtering plate is arranged between the pumping-in section and a primary impeller and is fixedly mounted on the pump body, a plurality of through holes are formed in the air filtering plate, a wheel disc is fixedly mounted on the transmission shaft, blades are arranged on the wheel disc, the pumping-out section is fixedly connected with a compensating shell, and a compensating seal mechanism used for preventing fluid from leaking is arranged between the compensating shell and the transmission shaft. The multi-stage centrifugal pump solves the technical problems of poor sealing performance, proneness to air binding formation and low pumping out efficiency of an existing multistage centrifugal pump and is widely applied to continuous fluid delivering.