38results about How to "Constrained degrees of freedom" patented technology

The invention discloses an active-passive combined vibration isolator based on positive-stiffness and negative-stiffness parallel connection. The active-passive combined vibration isolator based on positive-stiffness and negative-stiffness parallel connection comprises a basic platform (10), a load-bearing platform (30), a passive vibration isolation unit and an active vibration isolation unit, wherein the passive vibration isolation unit is provided with a positive-stiffness air spring (20) and a magnetic negative-stiffness mechanism (28) with adjustable negative stiffness in the first direction, so that the inherent frequency in the first direction is decreased, and the passive vibration isolation unit is provided with a stiffness-adjustable positive-stiffness leaf spring and a negative-stiffness inverted pendulum in the second direction, so that the inherent frequency in the second direction is decreased; the active vibration isolation unit is arranged at the outer side of the passive vibration isolation unit, the upper end of the active vibration isolation unit is linked with the load-bearing platform (30), and the lower end of the active vibration isolation unit is linked with the basic platform (10); and the active vibration isolation unit comprises displacement sensors, speed sensors, a proportional pressure valve and a voice coil motor, and the voice coil motor is used for fine adjustment of the load-bearing platform, so that vibration is further isolated. The active-passive combined vibration isolator based on positive-stiffness and negative-stiffness parallel connection has high bearing capacity, and active and passive vibration isolation of two degrees of freedom is achieved at the same time.

The invention relates to the technical field of rail vehicles, and discloses a traction beam structure, an end chassis with the traction beam structure and a rail vehicle. The traction beam structurecomprises a coupler mounting seat, a first traction beam body and a second traction beam body, wherein the first traction beam body and the second traction beam body are oppositely arranged and are arranged on the two sides of the coupler mounting seat correspondingly, the first traction beam body and the second traction beam body both comprise lower cover plates and traction beam web plates whichare arranged at the upper ends of the lower cover plates and are in butt joint with the lower cover plates, V-shaped grooves are formed in the butt joint positions of the lower cover plates and the traction beam web plates, and the edges of the traction beam web plates protrude out of the edges of the lower cover plates to form mounting parts. The traction beam structure has the advantages of being capable of realizing automatic welding, good in welding quality and small in deformation after welding.

The invention relates to a sector welding tool which can enable the welding positions between a sector and a master arm to be accurate, avoid the abnormal sound which is generated during the operation process of a lifter, and prolong the service life of the lifter. The sector welding tool comprises a plate body, wherein first location pins which are symmetrical to each other are arranged on the surface of the plate body, a groove which extends from the outer parts of the location pins to the edge of one side of the plate body is arranged on a central axis between the two first location pins, and a second location pin and a third location pin are respectively arranged in the groove along the length direction of the groove. Through the technical scheme, the tool adopts a double-point positioning mode, so the six freedom degrees of the sector can be effectively restrained, the sector is accurately positioned, the welding positions between the sector and the master arm are enabled to be accurate during the welding process, the abnormal sound which is generated during the operation process of the lifter is avoided, and meanwhile, the service life of the lifter is prolonged.

The invention provides a stretching and compressing both-way steel wire rope vibration isolator to overcome the defects of an existing vibration isolator. The stretching and compressing both-way steel wire rope vibration isolator comprises a cross guide rod, an upper outer side limiting block, an upper inner side limiting block, upper vibration isolation steel wire ropes, a sliding block, plate-shaped connecting pieces, lower vibration isolation steel wire ropes, a lower inner side limiting block and a lower outer side limiting block. The stretching and compressing both-way steel wire rope vibration isolator has the technical beneficial effects that the freedom degree of axial rotation of the vibration isolator is completely restrained, meanwhile, it is guaranteed that the vibration isolator cannot be bent, and the performance of the vibration isolator is guaranteed.

The invention discloses a fixture mechanism for creep feed grinding of tenon teeth of a turbine blade. According to the fixture mechanism, a supporting block, a blade body locating block, a side locating block and an axial locating pin are all locating points, are fixed to a main body and are used for locating the bottom face, the side face and the axial direction of the blade; a pressing rod is connected to a cover plate through a pin shaft; a front pressing head and a rear pressing head are connected to the two ends of the pressing rod through pin shafts; the cover plate, the pressing rod, the front pressing head and the rear pressing head form a whole and are arranged on the main body; a front pressing rod and a rear pressing rod are connected with a pressing rod body through pin shafts; a side pressing head is connected with the front pressing rod, a tail pressing head is connected with the rear pressing rod, and a side pressing plate assembly of a lever structure is formed; a leftguide plate and a right guide plate are fixed into grooves in the front ends of two bosses of the main body respectively; and a rapid locating clamping groove is formed in the bottom end of the mainbody and is used for being connected with a machining tool. The tool achieves a very good effect through on-site application. The fixture structure has the advantages of clamping convenience, accuracyand stability, thereby having important significance in optimizing and improving a process route.

The invention relates to a marine abandoned wellhead cutting device based on plasma arc cutting and application of the marine abandoned wellhead cutting device. The marine abandoned wellhead cutting device comprises a supporting mechanism, a rotating mechanism, a feeding mechanism, a cutting mechanism and a guiding mechanism. The supporting mechanism is used for providing underground support for the whole device and guaranteeing that the lower rotating mechanism of the supporting mechanism is located in the center of a casing pipe; the rotating mechanism is used for driving the feeding mechanism and the cutting mechanism to rotate so as to achieve the purpose of casing pipe girdling; the feeding mechanism is used for adjusting the distance between the cutting mechanism and the inner wall of the casing pipe; the cutting mechanism is used for generating high-temperature plasma arcs to realize cutting operation; and the guiding mechanism provides guiding for the whole device, and it is guaranteed that the device can be smoothly lowered in the axial direction of the casing pipe. The marine abandoned wellhead cutting device is simple and compact in structure, good in stability, low in equipment manufacturing cost and large in application range; by by using plasma arcs for cutting, the marine abandoned wellhead cutting device is small in cutting force, free of vibration, efficient incutting, free of pollution and capable of greatly reducing the operation cost so as to be good in economic benefit and market value and worthy of application and popularization.

The invention discloses a foot joint structure of a wheel type walking type vehicle steering drive axle. An upper mechanical leg is fixedly connected with a motor assembly; the motor assembly comprises two gear motors which are coaxial in output shaft and oppositely arranged, and the two gear motors serve as power sources and provide torque for wheel steering and foot joint movement; a transmission mechanism assembly can convert the single-direction output of the motor into two different-direction outputs, namely the rotation of wheels around a main pin and the rotation of the foot joint around the axis of the motor; a foot joint rotation locking mechanism is used for locking the rotation movement of the foot joint and positioning the position of the foot joint in a wheel steering mode, and a wheel steering locking mechanism is used for locking the steering of the wheels and positioning the position of the wheels in a foot joint rotation mode. The foot joint structure has two transmission routes, well decomposes the rotation motion of the foot joint around the wheel main pin and the rotation motion around a motor rotating shaft, switches the working modes by means of the two locking mechanisms, is reliable and effective, and has good application potential.

The invention relates to a box culvert carrying auxiliary support. The auxiliary support comprises a frame, wherein the frame comprises a first supporting plate and a second supporting plate, and thelength of the first supporting plate is greater than the length of the second supporting plate; the second supporting plate is rotationally connected to one end of the first supporting plate in the length direction through a hinge shaft, and the second supporting plate can rotate from a folded position to an unfolded position around the hinge shaft; a plurality of first baffles are arranged on theside wall, perpendicular to the hinge shaft, of the first supporting plate, and a plurality of second baffles are arranged on the side wall, away from the first supporting plate, of the second supporting plate; and when the second supporting plate is in the unfolded position, the first supporting plate and the second supporting plate are perpendicular to each other to form a containing area, andthe first baffles and the second baffles are arranged in a protruding mode towards the containing area. According to the box culvert carrying auxiliary support, a box culvert can be turned over 90 degrees before loading, and corners of the box culvert can be prevented from being damaged in the turning over process.