34results about How to "Accurate preload" patented technology

The invention discloses a super magnetostrictive actuator driving single-stage direct-acting jet pipe servo valve, and belongs to the technical field of hydraulic servo control. The servo valve comprises a valve body (16), a flow distributor (8), a pair of electro-mechanical converters, and a pair of micrometric displacement amplifiers positioned between the electro-mechanical converters and the flow distributor (8), wherein each electro-mechanical converter comprises a thermal compensation hood (5), a super magnetostrictive rod (10) mounted in the thermal compensation hood, and a coil frame (2) positioned outside the thermal compensation hood (5), and also comprises a drive coil (4) and a bias coil (3) which are orderly wound outside the coil frame (2); each micrometric displacement amplifier comprises a cylinder, a big piston (9) arranged at one end of the cylinder and connected with the corresponding super magnetostrictive rod (10); and the other end of the cylinder is connected with the flow distributor (8). The jet pipe servo valve has obvious characteristics of quick response, big driving power and control flow, and the like.

The invention provides a method and a device for exerting an anchor rod pretightening force and is suitable for general tunnel and roadway surrounding rock timbering engineering. During anchor rod pretightening force exerting, an anchor rod drilling hole is firstly constructed through a drilling machine, a resin medicine roll and an anchor rod are filled in the drilling hole sequentially, and a tray and a nut are sleeved on an external road section of the anchor rod. A pneumatic rock drill drives the anchor rod to rotate so as to break the medicine roll, and strength can be formed when the medicine roll is solidified; a hydraulic tensioner is installed; a hydraulic cylinder is started to exert a tension pretightening force on the anchor rod, and a suspended nut is screwed in by a wrench to be contacted with the tray; and the pressure of the hydraulic cylinder is reduced to be zero, and the hydraulic tensioner is removed. By means of the method and the device for exerting the anchor rod pretightening force, anchor rod pretightening force construction can meet the design requirements easily, the process that a traditional torque circumferential force is converted into an axial force in an anchor rod pretightening force construction method is changed, requirements on materials of the anchor is reduced, damage to the anchor rod is avoided, and the construction efficiency is improved.

The invention provides a space flexible arm pressing releasing mechanism for wire fuse unlocking, and belongs to the technical field of the space flexible arm pressing releasing mechanism. The space flexible arm pressing releasing mechanism comprises a fixed base, a wire fuse unlocking device, a pressing cover plate, a position detecting micro switch, phenyl silicone rubber sheets, torsion springs, hinge pins and limiting micro switches. Before launching, locking machines of the wire fuse unlocking device is adjusted, and proper pre-tightening force is applied to the pressing cover plate through stays to press a space flexible arm against the fixed base. After orbit injection, a command is sent from the ground, a cutter of the wire fuse unlocking device is energized, and a resistance wireof the cutter is rapidly heated to melt the stays. The space flexible arm pressing releasing mechanism for wire fuse unlocking is reliable in pressing and adopts the wire fuse unlocking device as a pressing and unlocking tool, the structure is simple, the relatively accurate pre-tightening force can be applied, and the assembly and adjustment are convenient; and no impact or vibration is generatedwhen unlocking, the space flexible arm can be protected from being damaged by the vibration shock load during launching, and the space flexible arm pressing releasing mechanism for wire fuse unlocking is suitable for the occasion in which the locking force of the space flexible arm is not required too much.

The invention discloses a device and a method for measuring a pretightening force of a bolt. The device comprises a holed bolt, and three temporarily pressed sheets, a specially-made nut, a pressure tester and a nut which sleeve the holed bolt are mutually overlapped sequentially from the top to the bottom, wherein a reserved hole in the holed bolt stretches out of the bottommost temporarily pressed sheet; a pin is horizontally inserted into the reserved hole in the holed bolt and stretches out along the two side walls of the holed bolt; a reserved groove in the specially-made nut sleeving the holed bolt is butted with the pin; the inside diameter of the pressure tester sleeving the holed bolt is greater than the outside diameter of the holed bolt, and the pressure tester does not contact the side wall of the holed bolt; the nut is screwed at the tail end of the holed bolt. The device calculates the pretightening force of the bolt by sequentially twisting the nut and the specially-made nut to stretch the bolt twice. The device improves the method for measuring the pretightening force of the bolt, improves the accuracy for measuring the pretightening force of the bolt, and finally measures a more accurate pretightening force, so that in the actual using process, the device is more convenient.

The invention belongs to the technical field of pushing pre-tightening devices, and particularly relates to a locknut pushing pre-tightening system. The system comprises a fixed base; a main nut, a pushing sliding piece, an auxiliary nut, and a main bolt are included; the main bolt is arranged on a connected part, the main nut is provided with a first thread hole, a thread groove is formed in thebottom end of the main nut, a second thread hole is formed in the auxiliary nut, a mounting groove is formed in the upper end of the auxiliary nut, the main bolt is sleeved with the pushing sliding piece, a first outer thread and a second outer thread are arranged on the outer side of the pushing sliding piece, a pushing spring is arranged in the mounting groove, the top end of the pushing slidingpiece is in threaded connection with the thread groove through the first outer thread, the bottom end of the pushing sliding piece is in threaded connection with the mounting groove through the second outer thread, and the bottom end of the pushing sliding piece is in contact fit with the pushing spring. The phenomenon that when the connected part vibrates, the main bolt loosens can be avoided; and firm connection of the main bolt and the main nut can be improved, and loosening can be avoided.

Disclosed is a one-dimensional heavy load sensor which is high in accuracy, high in rigidity, large in load and low in cost. The concrete filled steel tube structure is adopted as a bearing body, the outer portion of the concrete filled steel tube structure is of a cylindrical structure, two sets of resistance strain sheets are arranged in the bearing body, the first set comprises four resistance strain sheets vertically and evenly distributed on the contact surface of concrete and the steel tube, the other set comprises one resistance strain sheet which is arranged in the center of the concrete filled steel tube, the two ends of the resistance strain sheets are connected with wires, and the wires on the resistance strain sheets are connected to external equipment through through holes in the wall and the bottom end of the sensor. The concrete filled steel tube is adopted as the bearing body, the load bearing capacity is largely increased, and the size of the bearing body can be largely reduced. The sensor is provided with the two sets of resistance strain sheets which are five in number, so that the sensitivity and accuracy of the sensor are improved. The pressure heavy load sensor of the concrete filled steel tube has the advantages of being simple in structure, convenient to machine, reliable in performance, good in load bearing capacity, high in measurement accuracy, small in size, high in rigidity, stable in performance and the like.

The present invention belongs to the precision machinery engineering technology field, and especially relates to a precision matched bearing rapid adjustment device and a usage method thereof. The device comprises a single-bearing special measuring device and a matched bearing preload special measuring device. The device adjusts a matched bearing and applies preload at two ends of the matched bearing to avoid the problem that one bearing preload force is too large and another bearing has the unloading phenomenon in the preload loading process so as to allow the obtained matched bearing preload force to be more accurate and reasonable; a precision motor and a precision ball screw are employed to perform applying of the preload force of the matched bearing, the precision is high, and the stability is good; and moreover, the process of error test in the current operation process is avoided, the generation cost is saved, and the production efficiency is improved.

The invention provides a double-groove siamesed edge-contact spherical bearing, comprising an outer bearing ring, two arrays of bearing beads, two inner bearing rings, two support stands, an inner ring bushing, and a regulation gasket. Both ends of the outer bearing ring are respectively provided with a ring rolling channel corresponding with rolling channels of the two inner bearing rings, and form a contact angle; the inner ring bushing, a shoulder and the regulation gasket lock the inner bearing rings; the invention is assembled by a shaft, a craft gasket and craft screws into a detachable siamesed bearing. The invention adopts siamesed outer bearing rings, which can increase such size and position requirements as concentricity and perpendicularity of the shaft system, and endows the bearing with high precision, thus prolonging the service life of the bearings without increasing the working difficulty. The invention also has the advantages of simple structure, being convenient to be arranged, and adjustable axial preload and so on.

The invention provides a precise pre-tightening bolt. The precise pre-tightening bolt comprises a head, a screw, a mandrel and an indication wheel, wherein a through hole is formed in the end surfaceof the head, a blind hole is formed in one end of the screw, the end, where the blind hole is formed, of the screw is fixed with the head, and the though hole is coaxial with the blind hole; the mandrel is located in the through hole and the blind hole, one end of the mandrel is arranged at the bottom of the blind hole, the other end of the mandrel penetrates through the through hole and is fixedwith the indication wheel, and the distance between the indication wheel and the end surface of the head is the height increase distance of the blind hole after the precise pre-tightening bolt is mounted and reaches required pre-tightening force. The precise pre-tightening bolt has the advantages that the precise pre-tightening bolt can solve the problems that the pre-tightening force errors are large during pre-tightening mounting, pre-tightening is inconvenient and whether bolt pre-tightening is loose or not cannot be judged.

The invention discloses a precise chuck plate. The precise chuck plate comprises a threaded rotary disc, a fixed ring, clamping clacks, a guiding ring and a worm, wherein the threaded rotary disc is in a disc shape and comprises an annular side surface and a cylindrical outer surface; a first pre-tightened thread of which the lead direction is distributed in the radial direction of the threaded rotary disc is formed on the side surface of the threaded rotary disc; a gear structure is formed on the outer surface of the threaded rotary disc; the threaded rotary disc is accommodated in a cavity body of the fixed ring and can rotate around the axis of the fixed ring; the guide ring and the fixed ring are oppositely arranged and fixedly connected; the side surface of the guide ring makes contact with the other sides of the clamping clacks; and the worm and the threaded rotary disc form a worm wheel and worm transmission structure. According to the precise chuck plate provided by the invention, the shrinkable clamping clacks are arranged in the precise chuck plate, and the worm wheel and worm transmission structure is used, so that the function of controlling the clamping clacks to be shrunk or released synchronously and concentrically is achieved by screwing the worm; the structure of a clamping hoop is precise, and precise pre-tightening can be achieved; and in addition, pre-tightening operation is easy, the manual operation difficulty is reduced, and remote control operation is achieved conveniently through a mechanical hand.

The invention relates to the technical field of bearing pre-tightening, in particular to an angular contact bearing pre-tightening method. The method comprises the following steps that the length of a bearing inner ring mounting position is measured; the left side end of an angular contact bearing is provided with a first measuring block, and the right side end of the angular contact bearing is provided with a second measuring block; the thickness of the first measuring block and the thickness of the second measuring block are measured through a measuring instrument; the first measuring block and the second measuring block are installed in a mounting bearing outer ring part main body, so that the mounting end face is tightly attached to the main body mounting bearing end face; the high-precision measuring instrument is used for measuring the distance between the opposite end faces of the first measuring block and the second measuring block, the distance between the outer side end face of the first measuring block and the left side end face of the main body as well as the distance between the outer side end face of the second measuring block and the right side end face of the main body; the distance L between the two end faces of the mounting bearing outer ring part main body is calculated; and the thickness of a gasket is calculated through the value L. By adoption of the method, the accurate size of the angular contact bearing adjusting gasket is obtained by arranging the measuring blocks, and it is guaranteed that the pre-tightening force of the angular contact bearing is achieved.