405 results about "Pre tension" patented technology

Apparatus and methods for conditioning and pre-tensioning soft tissue grafts during joint repair surgery, such as during repair of the anterior cruciate ligament (ACL). The inventive apparatus is advantageously adapted and configured so as to enable a surgeon to independently apply a desired tensile load to individual graft strands or graft bundles of a multi-strand tissue graft. The inventive methods enable each graft strand or bundle to be properly tensioned so as to both “condition” the graft to prevent subsequent stretching, relaxation or elongation following surgery, which can destabilize the joint, and to pre-tension each graft strand or bundle to a predetermined amount so that each contributes to the strength and stability of the joint, thus resulting in a stronger and more durable joint. The tensioning device is advantageously equipped with structure for attachment to a patient's limb during the conditioning and pre-tensioning procedure. It has multiple adjustable tension applicators that can be independently manipulated so as to apply a separate tensile load to one or more ends of a tissue graft strand attached to each adjustable tension applicator.

A bottom garment for providing improved appearance to the wearer. The garment includes a front panel; a back panel; and at least one tummy control panel formed of a low-stretch, high pre-tensioned fabric attached to the inside of the front panel beneath the waistband of the front panel. In one embodiment, the low-stretch, high pre-tension fabric is formed of a mesh construction. The front panel may further include at least one pocket assembly.

Analyzing the mechanical state of an assembly modeled by a computer aided design system includes generating a model of a fastener and a part of the assembly. The fastener model includes an engaging region and the part model includes a receiving region to fastenably receive the engaging region. The fastener and the part are each represented by finite element representations that include elastically interconnected nodes. A tightening mesh interconnecting nodes of the engaging region and nodes of the receiving region is generated and a force applied between the nodes of the engaging and receiving region is determined based on a pre-tension force occurring upon engaging the engaging region with the receiving region.

A CMC airfoil (20) formed with CMC stitches (37) interconnected between opposed walls (26, 28) of the airfoil to restrain outward flexing of the walls resulting from pressurized cooling air within the airfoil. The airfoil may be formed of a ceramic fabric infused with a ceramic matrix and dried, and may be partially to fully cured. Then holes (32, 34) are formed in the opposed walls of the airfoil, and a ceramic stitching element such as ceramic fibers (36) or a ceramic tube (44) is threaded through the holes. The stitching element is infused with a wet ceramic matrix before or after threading, and is flared (38) or otherwise anchored to the walls (26, 28) to form a stitch (37) there between. The airfoil and stitch are then cured. If the airfoil is cured before stitching, a pre-tension is formed in the stitch due to relative curing shrinkage.

A device for eliminating oil particles from the crankcase ventilation gas of an internal combustion engine. The device is located in the flow duct of the gas that runs from the crankcase to an induction tract of the engine. The device includes an oil separator in the form of an outlet for the gas with a deflection of the flow, causing the oil particles to be deposited on a baffle surface and thus to be eliminated from the crankcase ventilation gas flow. The device has an infeed cross-section, which lies upstream of the baffle surface when viewed from the flow direction of the crankcase ventilation gas, and which is sub-divided into several infeed sub-sections. The baffle surface is a solid surface that is devoid of perforations. The baffle surface is configured on a valve body, which lies downstream of the infeed sub-sections when viewed in the flow direction of the gas, and which is pre-tensioned by a force. The valve body can be displaced in the opening direction in opposition to the pre-tension, as a result of the differential pressure in the gas between the crankcase and the induction tract.

The invention discloses a vibration measurement and control device and method of a rotary flexible hinge beam. The vibration measurement and control device comprises a flexible hinge beam body portion, a vibration signal detecting portion and a driving control portion. The flexible hinge beam is formed by connecting two beams through a hinge, and a prestretching shape memory alloy wire is arranged between the two beams, and is used for restraining low-frequency large-amplitude bending vibration of the connecting position. A piezoelectric ceramic piece sensor and a piezoelectric ceramic piece driver are pasted on to the front face and the rear face, close to a mechanical tightening device, of the flexible hinge beam respectively, and are used for detecting and restraining the bending vibration of the hinge beam. An acceleration sensor used for detecting vibration is arranged at the tail end of the hinge beam. The device is used for simulating vibration measurement and control over a space flexible joint and a flexible mechanical arm, the sensors and the composite control drivers are adopted, the corresponding control algorithm is operated, and active control over the bending vibration of the rotary hinge flexile beam is achieved.

The invention relates to a method for manufacturing a permanent-magnet excited rotor for a high speed electric motor, according to which method a support sleeve (1) is mounted with a pre-tension around the rotor body (2), characterised in that the sleeve is expanded by a liquid that solidifies and is solid at the working temperatures of the rotor, said liquid is injected under pressure between the sleeve and the rotor body and held under pressure during solidification.

The invention relates to a closure for a container that holds a free-flowing product. The container is characterized by the following: a fixed lower part which can be fastened to a container neck that surrounds a container opening in order to seal said neck; a cover comprising a protruding connecting piece that forms a passage for the free-flowing product; a displaceable upper part which can be coaxially displaced on the lower part in and against the direction of the container between an outer resting position and an inner actuating position; a breaker or dish-shaped diaphragm valve which has a base consisting at least of a flexible elastic material and whose upper edge seals the underside of the upper part; perforations in the base of the diaphragm valve which are closed in the testing position of the upper part; and a diameter of the base that is greater than the inner cross section of the connecting piece. The outer end of the connecting piece continuously supports the base of the diaphragm valve, and the latter continuously pre-tensions the upper part in the direction of its resting position in such a way that, when axial pressure is exerted on the upper part in the direction of the container, the diaphragm valve is bent outwards, thus opening the perforations in the base.

The invention discloses a positive/negative pressure vacuum film covering machine, and belongs to the technical field of mechanical devices. The positive/negative pressure vacuum film covering machine is composed of a main machine, a hydraulic system, a heating system, an electric system and a positive and negative system. The main machine comprises an upper cylinder, an upper beam, an upper vacuum chamber, a film pressing plate, a lower vacuum chamber, a lower beam, stand columns, a film pressing cylinder and a lower cylinder. The hydraulic system is located on the rear side of the main machine. The heating system is arranged at the top end in the upper vacuum chamber. The electric system is located on the right side of the main machine. The positive/negative pressure system is located on the left side of a machine body. A main body is a closed cavity, the closed cavity is partitioned into two independent air chambers through a decorative film, the forming process is conducted in the same closed space and not likely to be affected by the external environment, and the stability of processing can be improved so as to achieve the purpose of improving positioning accuracy; the elongation of the film can be improved by the adoption of prestretching, the interior of a plastic part can be wrapped by the film smoothly, and the high-quality film-decorative plastic part is obtained.

The invention discloses a process for cutting a silicon wafer by using a steel wire with the diameter of 0.1mm. In the process, silicon carbide (SiC) and a cutting fluid are proportioned according to the mass ratio of 1:1 to 1:1.2; in a glue curing process, single crystals are pressurized for 0.5 to 3h by a 5 to 10kg heavy pressurizing punch to remove redundant glue; and the cutting is performed by using the steel wire with the diameter of 0.10mm under the pre-tension of 15 to 23N, a wire speed is 400 to 1,000m/min, the descending speed of a workbench is 0.3 to 1mm/min, and a cutting stroke is set according to the actual diameter of the single crystal. The process for cutting the silicon wafer by using the steel wire with the diameter of 0.1mm can effectively reduce cutting loss and improve the quality of a cut surface, achieves more remarkable benefits if the silicon wafer is thinner, and compared with the processes in which the steel wires with the diameters of 0.14mm and 0.12mm are adopted generally, saves raw materials by 6.45 percent and 2.15 percent respectively.

The invention is a method of erecting all-cantilever erected steel truss beams assisted by diagonal ropes, as well as a relevant system. The method utilizes a bearer cable tower combined with a steel structure center tower column with diagonal ropes; install a tower-type crane on the top face of the steel truss beam end at the first hole with an overhead bridge crane in a ground craning station; anchor cases below the front and rear diagonal ropes are connected with side plates at steel beam nodes, and after that, directly lift the tower to apply pre-tension on the diagonal ropes; perform all-cantilever erection for the front steel truss beam. After finishing erection of the orifice steel beam, complet load removal from the diagonal ropes with a method of pushing up the temporary seat for the front pier and lowering back a pushing and craning device between upper and lower seats of the bearer cable tower. The system comprises an auxiliary tower truss, a tower center vertical column, the upper and lower support seats, the front and rear diagonal ropes, the upper and lower anchor cases for diagonal ropes, a tower top anchor beam and a walking mechanism. The invention has the following advantages: For large-span continuous steel truss beams, utilize a special device additionally to erect multi-span steel truss beams, so as to reduce internal stress in installation of steel truss beam members, lower end deflection of the front extension arm, and increase the inclination stability of a steel truss beam on the extension arm. Meanwhile, the invention can low investment and short construction period and provide very convenient operation.

The invention relates to a reinforcing system and reinforcing method of a wind power generation tower foundation ring foundation. The system comprises the foundation ring foundation (1) and a draught fan tower drum (2). The foundation ring foundation (1) comprises a foundation bottom plate (10), a concrete column pier (9) and a foundation ring (8), and the foundation ring (8) is connected with the draught fan tower drum (2). Steel beams (5) are symmetrically arranged on the outer side of the foundation ring (8) and on the top of the concrete column pier (9), the steel beams (5) surround the foundation ring (8) to form a regular-hexagon-shaped area, and steel-reinforced concrete beams (6) are poured around the regular-hexagon-shaped steel beams (5) and on the outer side of the foundation ring (8). The two ends of the steel beams (5) are connected with prestress anchor rod assemblies (7), and the lower ends of the stress anchor rod assemblies (7) are anchored in the foundation bottom plate (10). Pre-tension force is applied to a prestress anchor rod, so that pre-compressive stress is generated on concrete around the foundation ring, and accordingly the crack problem of the foundation ring foundation caused by fatigue can be fundamentally solved.

The invention discloses a steel belt deviation correction system of a cooling forming machine for remote transportation of a high-temperature material. A driving wheel and a driven wheel are connected through a steel belt, wherein one end of the driving wheel is fixed, and the other end of the driving wheel is fixed through a hydraulic cylinder; the two ends of the driven wheel are fixed respectively through a cylinder; the pre-tension of the steel belt between the driving and driven wheels is adjusted by two cylinders; the bottom of the steel belt is provided with a driving wheel carrier roller and a driven wheel carrier roller to support the bottom of the steel belt respectively; a compression roller is arranged at the upper side of the bottom of the steel belt between the driving wheel carrier roller and the driven wheel carrier roller; limit switches are arranged close to the bottoms at the two sides of the driven wheel steel belt respectively, limit switches are arranged close to the tops at the two sides of the driving wheel respectively, and each limit switch is connected with an alarm; the driven wheel is provided with a photoelectric sensor close to the bottom of each cylinder, a photoelectric sensor is arranged at a position, which is close to the top of the hydraulic cylinder, on the driving wheel, and the photoelectric sensors detect the deviation quantity of the steel belt respectively; and all the sensors and limit switch alarms are connected with an upper computer through a PLC (programmable logic controller). According to the invention, double-closed-loop control on the position of the steel belt at the driving wheel end and driven wheel end is realized, and real-time deviation correction of the steel belt transmission system is finished.

The invention discloses a preparation method of an Al-Cu-Li-X series aluminum lithium alloy sheet. The sheet prepared by the method is 0.8mm-8.0mm in thickness. The method comprises the following steps: cogging and hot-rolling homogenized slab ingots to a specified thickness and coiling; carrying out annealing treatment, uncoiling and carrying out band-type cold-rolling; carrying out intermediate annealing according to deformation during cold-rolling, thus obtaining the sheets with uniform thicknesses. The sheets can be in different states after being subjected to solution treatment, prestretching and aging treatment, so as to meet different usage requirements. Compared with the prior art, the aluminum lithium alloy sheet with high surface quality, uniform sheet size and smooth sheet shape is prepared by the method through band-type cold-rolling. The sheets can be in different states by different heat-treating processes, so as to meet usage requirements under different application conditions.

The invention provides a planet gear unit for a planet carrier with a planet load plate. The planet carrier is provided with at least a planet shaft; therefore, on the both sides of the load plate, the planet wheel is arranged on the planet shaft through a taper roller bearing, and the extremities of the planet shaft are provided with axial shifting parts to forms a support; the support provides axial support for an internal bearing ring of the taper roller bearing; a tension device is arranged on the planet shaft, which enables the axial shifting part to mutually shift and is used for controlling the pre-tension of the taper roller bearing. By shifting the axial shifting part through the tension device, the pre-tension on the taper roller planet bearing can be controlled, so as to avoid or at least limit the gap in the bearing, thereby reducing the failure of the planet bearing caused by misplacement and dynamic effect.

Pre-tension and post-tension processes for the manufacture of pre-stressed structures in which bonded carbon fiber cables are provided with burial anchors and temporary anchors outward of the burial anchors. The burial anchors are embedded in the structure. The temporary anchors enable stressing of the carbon fiber cables.

The invention provides a drawing and hydraulic integrated forming method. The method comprises the following steps of: step 1: pre-drawing a sheet material, step 2: closing a die; step 3: expanding by introducing a liquid, step 4: releasing the pressure of a liquid chamber, opening the die and taking out the molded part. The drawing and hydraulic integrated forming method provided by the invention can solve the rebound problem of the molded part while well ensuring surface quality and wall thickness distribution of the part. Besides, the formed part has a high surface quality and a uniform distribution of wall thickness.

A weight compensation device for a lifting door, includes a spring element and a tensile element, which can be wound onto or unwound from a winding device in such a way that the spring element achieves its greatest pre-tension when the door leaf is in the closed position and is essentially tension-free when the door leaf is in the open position. The tensile element is narrower at the end facing the winding device than at the end facing the spring element and the winding device includes a guide device, which is used to wind the tensile element in such a way that the wound layers lie adjacent to one another without making contact. To achieve this, the guide faces around the perimeter of the guide device have a continuously increasing radius in the winding direction. This enables the provision of a weight compensation device that achieves the torques required for effective weight compensation by means of a simple construction. This also relates to a lifting door that is equipped with a weight compensation device of this type.