49results about How to "Consistent compression" patented technology

The invention relates to a cam roller negative stiffness structure low-frequency vibration isolator. According to the low-frequency vibration isolator, a positive and negative stiffness parallel connection principle is adopted, a positive stiffness element and a negative stiffness element are connected in parallel, system resonance is restrained in combination with an added damping device, and protection is provided for drastic situations. A positive stiffness adjustment device and a negative stiffness adjustment device are used for realizing effective and accurate adjustment of the positive stiffness range and negative stiffness range to meet different bearing mass and vibration isolation requirements. The problems that an existing low-frequency vibration isolator is inconvenient to install, complex in structure, poor in work condition adaptability and the like are solved.

The invention discloses a flexible die releasing method of a closed die forging large irregular profile structure forge piece. The flexible die releasing method comprises the steps that an upper forging die is taken out firstly and then force is applied to pushing rods to push up the large irregular profile structure forge piece in a lower forging die; flexible sections of each pushing rod are compressed to the elastic limit, and the compression amount is equal; when push-out force of a certain pushing rod is larger than frictional resistance of the position, located on the pushing rod, of the forging piece and a die mold cavity, the position of the forging piece loosens firstly and produces certain displacement, the pushing rod is not separated from the forging piece, the situation same with the just pushing rod occurs gradually on the other one pushing rod or the other multiple pushing rods, and the process occurs randomly and is conducted continuously; and when the total push-out force of all the pushing rods is larger than the total frictional resistance of the forging piece, the forging piece loosens overall, bears relatively-even force and is steadily pushed out of the die mold cavity. According to the flexible die releasing method, the die releasing process of the forging piece becomes steadier and is not liable to damage, and the flexible die releasing method is mainly used for die releasing after forging of forging pieces such as large aircraft structural pieces.

The invention relates to a transverse shock absorber for locomotives, which belongs to the technical field of locomotives and comprises a pressure cylinder mounted in an oil storage cylinder. An oil return cavity is formed between the oil storage cylinder and the pressure cylinder, the pressure cylinder is peripherally matched with a piston on the head of a piston rod, and the piston rod extends out from the other end, away from a mounting end, of the oil storage cylinder and is fixedly connected with another mounting end with a dustproof tube. An end cover is fixed into the other end of the oil storage cylinder, a damping valve and a first one-way valve are mounted on the end cover and a bottom valve respectively, a second one-way valve is mounted on the piston, one end of the end cover is provided with a stepped hole, the bottom of the stepped hole is provided with a shrinkage hole which forms an annular groove with the piston rod, the shrinkage hole is communicated with the interior of the pressure cylinder, and a radial damping valve and an axial oil return pipe communicated with the oil return cavity are mounted on the end cover at the position corresponding to the shrinkage hole. The transverse shock absorber is high in processing and assembly manufacturability and more effective in damping, the compression damping force and the stretch damping force are basically uniform, and the symmetry rate can reach more than 90%.

The invention discloses a sealing structure for a sealing box. The sealing structure comprises an annular accommodating groove (1) positioned on an upper edge of a box body, an annular elastic sealing piece (2) accommodated in the accommodating groove (1), and a pressing plate (3) which is arranged on a box cover and is used for pressing against the elastic sealing piece (2), wherein a contact surface between the pressing plate (3) and the elastic sealing piece (2) is a plane; the elastic sealing piece (2) and the pressing plate (3) are pressed against each other through a pressing device arranged on the box body and the box cover; the elastic sealing piece (2) has the hardness of 45-50 degrees and the compression of 1-1.5mm; and the pressing plate (3) has the surface flatness of not more than 0.4. The sealing structure for the sealing box is good in sealing effect and high in insulating level, and has a protection level of IP67.

The invention relates to a three-dimensional stacked packaging module single-board testing tool. The three-dimensional stacked packaging module single-board testing tool is composed of four parts of a control signal and radiofrequency signal circuit board and an installation module thereof (1010), a vertical interconnection connector and an installation frame thereof (1020), a circuit board to be tested and a fixing frame thereof (1030) and a radiofrequency signal output module (1040). The vertical interconnection connector and the installation frame thereof (1020) are composed of an installation frame (1021), vertical transition connectors (1022) and guide sleeves (1023); the circuit board to be tested and the fixing frame thereof (1030) are composed of a metal plate to be tested (1031) and a circuit board (1032); and the signal output module (1040) is composed of radio frequency connectors (1041), hexagon copper posts (1042), fuzz button conversion coaxial connectors (1043), guide pillars (1044), a mounting base plate (1045), microstrip boards (1046) and cover plates (1047). By employing the three-dimensional stacked packaging module single-board testing tool, the contact area of a radiator is increased, space of the thermal design is expanded, natural heat dissipation can satisfy the demand, and the difficulty level and cost of the thermal design are reduced.

The invention discloses a prefabricated assembled structure multi-point cooperative splicing system and method. The prefabricated assembled structure multi-point cooperative splicing system comprisesprefabricated assembled underground structure splicing center control equipment, a plurality of hydraulic jacks on splicing pieces, a plurality of laser distance measuring instruments arranged on thesplicing pieces and a plurality of laser reflecting plates arranged on a target piece. By utilization of a component rubber pad counter-force centroid algorithm, a tensioning method based on centroidtracking and slit width control, an assembled component splicing frictional resistance calculating method, a multi-point cooperative communication and multi-mode protection method, a multi-point cooperative loading control method and other methods and algorithms, simultaneous different-amount accurate output control over the tensioning force and the tensioning speed when the different jacks are tensioned is achieved, accordingly, the prefabricated assembled component splicing control effect is effectively improved, smooth and safe proceeding of splicing is guaranteed, accurate output control is achieved, the assembling quality is improved, structure damage is avoided, and the prefabricated assembled component splicing control effect can be effectively improved.

The invention discloses a test fixture for a broadband radio frequency BGA interface system-in-package product. The test fixture comprises a pressure applying device, a test fixture base, a test mother board, an elastic diaphragm and a positioning mechanism; the pressure applying device comprises a guide mechanism, a pressing plate, a spinning nut and a screwing handle; a guide groove is formed inthe guide mechanism, and a threaded hole matched with the spinning nut is formed in the upper part of the guide groove; the pressing plate is installed in the guide groove, and the spinning nut is arranged in the threaded hole. And the screwing handle is used for screwing the spinning nut. According to the pressure applying device, one spinning nut is adopted to apply pressure to the pressing plate, the pressing plate applies pressure to the BGA packaging product to be tested stably and uniformly in the pressing process, the compression amount of each BGA solder ball on the BGA packaging product to be tested to the elastic diaphragm is consistent, and radio frequency signal communication is stable and reliable.

The invention discloses a dynamic sealing structure of a main shaft of a large high speed geotechnical centrifuge, which has strong adaptability, including a combined sealing form of a multi-channel labyrinth sealing structure, a one-channel spiral sealing structure and a one-channel stuffing sealing structure. The dynamic sealing structure of the main shaft of the large high speed geotechnical centrifuge can be applied to vacuum dynamic seal and achieve oil seal under atmospheric pressure, and has long service life. The stuffing seals with wear are opened on demand through a structure of a first screw, a compaction mechanism and a gland combination, and are used only in a limited period of time when a centrifuge chamber is pumped vacuum. The vacuum dynamic seal has strong reliability, andis provided with a compression mechanism with springs in design to ensure that after the stuffing is worn out, the gland can still press the stuffing. The replacement and switching operation of the compression mechanism is simple. Arc grooves and T-shaped grooves corresponding to the compression mechanism are respectively arranged on the gland and a static ring, thereby being convenient to replace the compression mechanism. The compression is designed with a limit sleeve to guarantee the same compression amount of the springs in each compression mechanism and further reduce the difficulty ofmanual operations.

The invention provides a valve head, a parallel error automatic compensating device and an electron microscope. The valve head comprises a movable member bearer, a movable member which is accommodated in the mounting hole of the movable member bearer, and movable member supporting device which supports the movable member for floating relative to a fixed member in a direction which is opposite to the fixed member. The movable member has a second sealing plane which matches a first sealing plane of the fixed member, and a circumferential surface which is connected with the second sealing plane and is opposite to the fixed member. The circumferential surface is partially a spherical surface at least in the axial direction of the movable member. The mounting hole has a cylindrical surface which matches the spherical surface. When the movable member floats in a certain floating angle, the spherical surface is always in circumferential linear contact with the cylindrical surface of the mounting hole. According to the valve head provided by the invention, a parallelism error between two planes in each direction can be eliminated, thereby realizing sufficient fitting of the two sealing planes. The parallel error automatic compensating device with the valve head, and the electron microscope with the compensating device can ensure sealing repetition.

The invention discloses a fuel cell stack assembly method which comprises the steps of (S1) stacking stack components in order, (S2) adjusting the positions of the components by positioning holes, (S3) applying a small amount of torque and fixing the components including the steps of threadingly connecting and fixing fastening nuts to positioning columns, applying a small amount of torsion force to fix the stack components including a stack lower end plate, a lower collecting plate, a stack single cell, an upper collecting plate and a stack upper end plate through the positioning columns, and(S4) horizontally placing the stack components. In the invention, according to the fuel cell stack assembly method, the small amount of torque is applied in step (S3), after the components are fixed,the stack components are horizontally placed through the step (S4), then the lateral assembly is used to uniformly apply pressure in each direction, therefore, the uniform stress of each position of astack is ensured, the compression of a membrane electrode is consistent, the flow resistance distribution is more uniform, and the simulation and analysis of the stack are facilitated.

The invention discloses a rotary type unilateral opening adjustable sealing structure. The sealing structure comprises a box body, a box cover, a connecting pipe, a seal ring, a rotating device and alocking device, wherein the rotating device comprises a rotating seat and a rotating shaft, the connecting pipe is rotationally connected with the box cover through the rotating shaft, the locking device is arranged on the side opposite to the rotating device, the locking device comprises a clamping hook assembly and a lock catch assembly, the clamping hook assembly comprises a dovetail groove, fixing bolt holes, adjusting fixing bolt holes and a clamping hook, the fixing bolt holes are formed in the surface of the clamping hook assembly, the adjusting fixing bolt holes are arranged on the twosides of the clamping hook assembly, the clamping hook is arranged at the protruding part of the clamping hook assembly, moreover, an arc-shaped groove is formed in the tail end of the clamping hook,the lock catch assembly comprises a lock catch base and a lock catch, the lock catch base is fixed on the surface of the box cover, the buckling part of the lock catch is connected with the clampinghook in a buckling mode, the two sides, inside the rotating device, of the rotating seat are also provided with adjusting fixing bolt holes, and the surface of a pressing plate of the connecting pipeis also provided with adjusting bolt holes matched with the adjusting fixing bolt holes.

The invention discloses a distribution transformer cover plate which relates to the technical field of transformer devices. The distribution transformer cover plate comprises a square cover plate body and is characterized in that the upper cover surface of the cover plate body is a flat end surface, four sides of the cover plate body respectively extend by 60mm to be used as flanges, four corners of the flanges are respectively provided with a gap, and front 30-mm parts of the four flanges are inwards bent to form included angles of 90 DEG, so that edges are formed. The distribution transformer cover plate is flat, and is little in deformation of boat shape and waves, attractive in appearance and little in labor intensity; a temporary reinforcing rib is not needed to be welded or the thickness of a steel plate is not needed to be increased. The contact surface of the distribution transformer cover plate and a box edge sealing member is flat, the compression amounts of sealing members are consistent, and the leakage probability is reduced.

The invention provides a valve head, a parallel error automatic compensation device and an electron microscope. The valve head comprises a movable member and a movable member supporting means. The movable member is provided with a second sealing plane matched with a first sealing plane of a fixed member. One side of the movable member, back on to the fixed member, is provided with a first accommodating groove. The movable member supporting means is provided with a spherical surface adapted to be embedded in the first accommodating groove. The spherical surface is in point contact with the groove bottom holding point of the first accommodating groove. The spherical surface is in line contact with the groove wall of the first accommodating groove. The spherical surface is used for supporting the movable member to float relative to the fixed member in a direction back on to the fixed member. According to the technical scheme of the invention, the valve head is low in machining difficulty and high in adjustment sensitivity, wherein the parallelism error of two planes in each direction can be eliminated. Therefore, the two sealing planes can be adequately fitted with each other. The invention also provides a parallel error automatic compensation device provided with the above valve head, and an electron microscope provided with the compensation device and used for ensuring the sealing repeatability.

The invention discloses a non-contact heating flip-chip bonding process method, which comprises the following steps: providing flip-chip bonding equipment, and preparing a chip with solder ball bumpsand a tube shell with a bonding pad; enabling the face, provided with the solder ball bumps, of the chip to be opposite to the tube shell; moving a suction head carrying the chip to a corresponding welding position above the tube shell; pressing the tube shell downwards by the suction head carrying the chip, and stopping movement of the suction head when the pressure between the solder ball bumpand the bonding pad reaches the preset contact force; leaving the chip by the suction head and lifting the chip upwards; starting suction head heating, heating the surface of the suction head to a preset temperature, maintaining the temperature for corresponding time, and heating the chip to melt the solder ball; and stopping heating of the suction head and lifting the suction head to reset, and completing welding of the chip and the tube shell. According to the process method, the whole process flow is simplified, the production efficiency is greatly improved, the chip and the tube shell havea self-alignment effect in the welding process, and a problem that the solder ball bumps are compressed unevenly due to mechanical stress between the solder ball bumps and the bonding pads can be effectively solved.

A surgical compression gauge instrument comprising a compression gauge jaw member and an anvil jaw member for measuring a reactionary force from tissue captured and compressed to a predetermined gap distance between the two jaw members is disclosed herein. The compression gauge jaw member comprises a force gauge assembly for measuring the tissue reactionary force, and a gap sensor for generating an electrical signal indicative of the gap distance between the two jaw members.