335 results about "Leadscrew" patented technology

A control rod drive mechanism (CRDM) for use in a nuclear reactor, the CRDM comprising: a connecting rod connected with at least one control rod; a lead screw; a drive mechanism configured to linearly translate the lead screw; an electromagnet coil assembly; and a latching assembly that latches the connecting rod to the lead screw responsive to energizing the electromagnet coil assembly and unlatches the connecting rod from the lead screw responsive to deenergizing the electromagnet coil assembly. The latching assembly is secured with and linearly translates with the lead screw, while the electromagnet coil assembly does not move with the lead screw. The electromagnet coil assembly is at least coextensive with a linear translation stroke over which the drive mechanism is configured to linearly translate the lead screw.

A control rod drive mechanism (CRDM) comprises a lead screw, a motor threadedly coupled with the lead screw to linearly drive the lead screw in an insertion direction or an opposite withdrawal direction, a latch assembly secured with the lead screw and configured to (i) latch to a connecting rod and to (ii) unlatch from the connecting rod, the connecting rod being free to move in the insertion direction when unlatched, and a release mechanism configured to selectively unlatch the latch assembly from the connecting rod.

A drug delivery device drive that includes a single shape memory alloy wire actuator to advance a lead screw via a ratcheting mechanism and method thereof are disclosed. In one embodiment, a shape memory alloy wire is operably connected to one of a pair of ratchet wheels and configured to drive incrementally the rotation of the connected ratchet wheel via a contraction, which in turn drives the rotation of the other ratchet wheel about a rotational axis which moves a lead screw and advances a plunger to dispense a liquid drug from a drug container. A drug delivery device using the shape memory alloy wire actuator in combination with the ratcheting mechanism to incrementally rotate a shaft, a lead screw or a sleeve provides for a more compact an less complicated design.

Described is a drive mechanism for a drug infusion pump. In one embodiment, an in-line drive mechanism is provided that includes a motor operatively coupled to a lead screw, which is configured to engage a piston. The piston includes a cavity to receive the motor and the lead screw such that the lead screw and at least a portion of the motor are substantially contained within the piston cavity when the piston is in a retracted position. In one embodiment, at least a portion of the motor is also substantially contained within a cavity of the lead screw regardless of whether the piston is in the retracted or extended position. The configuration of the piston, the lead screw and the motor results in a more compact drug delivery device.

An improved lead screw actuator for use in applications including power vehicle windows is provided that significantly reduces the amount of machining that must be performed on the lead screw to enable secure attachment of a gear or pulley. The lead screw has a plurality of threads on its outer annular surface and a first and second axially spaced circumferential groove. A gear or pulley disposed about the lead screw has a female thread formed into an inner annular surface that is configured to engage at least one of the plurality of threads of the lead screw between the first and second grooves. A pair of rings are disposed within the first and second grooves in order to restrict axial movement of the gear or pulley on the lead screw.

A method for gripping objects by means of a robotic gripper mechanism is provided, wherein the gripping mechanism comprises gripping jaws, a wedge actuator between the gripping jaws, wherein the wedge actuator moves the gripping jaws together and apart as it slides backward and forward, and a motor that moves the wedge actuator by means of a connecting leadscrew. The method comprises applying current to the motor so that the motor reaches maximum operating speed before the gripper mechanism comes into contact with any object. When the gripping jaws contact an object, e.g., media cartridge, they collapse over the object, gripping it. The inertia from the rotating mass of the motor increases the force and speed of the gripping action. In another embodiment, a flywheel may be added to the leadscrew to provide additional rotating mass and increase the inertia before contact.

A power swing door actuator for moving a passenger swing door relative to a body portion of a motor vehicle. The power swing door actuator includes a housing rigidly fixed to the swing door, a motor mounted to the housing, a connector link having a first end pivotably coupled to the vehicle body portion and a second end pivotably coupled to a drive nut of a spindle drive mechanism. A leadscrew of the spindle drive mechanism is rotatably driven by the motor for causing relative translational movement between the drive nut and the leadscrew which, in turn, results in pivoting movement of the connector link while the vehicle door swings between open and closed positions in response to selective actuation of the motor.

A syringe pump has a motor rotating a leadscrew to drive a plunger head actuator along it. The head actuator engages the plunger of a syringe and moves the plunger along the syringe barrel to dispense medication. An optical encoder mounted on the leadscrew is rotated by the motor to produce a pulse output. A control unit times the interval between the pulses and compares these timings with a stored value representative of a predetermined multiple of the minimum time. If the head actuator is obstructed, the speed of rotation of the motor is slowed and the time interval between pulses rises. When this exceeds the stored value, the control unit stops the drive to the head actuator and generates an alarm.

A syringe pump has a motor rotating a leadscrew, which drives a plunger head retainer to push a plunger along the barrel of a syringe so as to dispense medication to a patient. A force sensor in the head retainer measures the force on the plunger to detect when there is an occlusion restricting flow of medication. When an excess force is detected an alarm is generated and the motor is reversed to reduce the force to about 10% of that at which the occlusion is detected. The occlusion can be removed with a reduced risk of a bolus of medication being dispensed after which the user restarts the pump so that the plunger is driven normally.

An electromechanical strut and method of moving a closure member of a vehicle between an open position and a closed position is provided. The electromechanical strut includes a power drive unit including a motor, a leadscrew, a planetary gearset operably connecting the motor to the leadscrew, and an electromechanical brake assembly. The electromechanical strut further includes a telescoping unit including an extensible tube and a drive nut for converting rotary motion of the leadscrew into linear motion of the telescoping unit. The electromechanical brake assembly is selectively moveable between an engaged state, wherein the leadscrew is prevented from rotating to prevent relative axial movement between the power drive unit and the telescoping unit, and a disengaged state, wherein the leadscrew is permitted to rotate to allow relative axial movement between the power drive unit and the telescoping unit.

An electric parking brake assembly includes an electric motor having an output shaft, a control module coupled to the electric motor for controlling the electric motor and a transmission coupling a threaded lead screw to the output shaft of the electric motor. The transmission preferably includes a gear train having a plurality of helical gears and the lead screw and the output shaft are preferably coaxial. A stationary elongate guide shaft extends substantially parallel to and spaced apart from the lead screw. A drive nut has a lead screw bore threadably receiving the lead screw therein and a guide shaft bore slidingly receiving the elongate guide shaft therein. The drive nut also has a cable attachment for attaching a brake cable to the drive nut. The cable attachment has a central axis offset from a central axis of the lead screw and is preferably located midway between the lead screw bore and the guide shaft bore. The control module controls the electric motor such that rotation of the output shaft causes motion of the transmission and rotation of the lead screw, rotation of the lead screw causes linear motion of the drive nut along the lead screw and the guide shaft, and linear motion of the drive nut causes tensioning and untensioning of the brake cable. The assembly preferably includes a manual override device operatively connected to the lead screw. The manual override device selectively causes manual rotation of the lead screw, rotation of the lead screw causes linear motion of the drive nut, and linear motion of the drive nut causes tensioning and untensioning of the brake cable.

A motor with a shaft and a shaft axis is disposed within a housing. A lead screw has an axis and is rotatably mounted in the housing. A deadbolt linearly extends from the housing based on rotation of the lead screw. A gear set with a plurality of gears, each having an axis, is disposed in the housing and operably connects the motor and the lead screw. A circuit board is disposed within the housing and has a plurality of portions communicatively connected by a ribbon. Each portion is disposed substantially orthogonal to the motor shaft axis, the lead screw axis, and the plurality of gear axes.

The invention discloses a gear machining punching device capable of preventing punching offset and adjusting the pore diameter and a punching method. The gear machining punching device comprises a base plate, belt pulley mechanisms, a rotary motor and a storage platform; a servo motor is installed at the bottom of the base plate, the belt pulley mechanisms are installed at the outer sides of leadscrews, the rotary motor is installed on the upper end face of a top plate, movable grooves are reserved in the two ends of the top plate, and locking bolts are arranged at the outer sides of adjusting rods; guide blocks are connected to the bottoms of the adjusting rods, fixed plates are fixed to the upper end face of the base plate, movable rods penetrate through the interiors of the fixed plates, clamping plates are connected to the ends of the movable rods, and connected with the fixed plates through springs, and the storage platform penetrates through the middle of the base plate. According to the gear machining punching device capable of preventing offset and adjusting the pore diameter, by replacing punching heads with different diameters, pores with different sizes can be obtainedthrough punching, besides, the phenomenon of positional offset in the punching process can be avoided, and the practicability of the punching device is improved.

A lead screw assembly having a lead screw rotatable within a hollow tubular portion of a reinforcing rail. A nut engages with threads of the lead screw and is movable along the reinforcing rail. The lead screw includes plurality of first threaded portions having an outer diameter and extending lengthwise of the lead screw; and at least one second gap portion having an outer diameter that is less than the outer diameter of the first threaded portions. The second gap portion is positioned between adjacent first threaded portions of the lead screw. At least one generally U-shaped bearing is secured within the reinforcing rail and contacts the lead screw at a second gap portion. Each U-shaped bearing supports the lead screw along its length as the screw rotates within the rail, so that the lead screw assembly can be safely operated at high speeds over comparatively long distances while minimizing whipping and vibration of the lead screw. The reinforcing rail can include a base portion which permits the assembly to be securely mounted to a support structure at any convenient location along its length. An anti-backlash nut assembly includes a threaded follower for engagement with the threads of a lead screw. A pair of wedges bias the follower in a radial direction so that the threads of the follower are brought into forcible engagement with the mating threads of the screw. In a preferred embodiment, the nut assembly is adjustable to provide variable levels of backlash resistance and wear-compensation.

A drive for adjusting parts of seating and reclining furniture is provided, which includes: an electric motor, disposed within a motor cover of a cabinet and engaged with a gear connected to a lead screw via one end of a drive shaft of the electric motor, and a slider, for moving rectilinearly back and forth in cooperation with the lead screw. The slider is provided with a drive nut therein, which is screwed onto the lead screw to enable the slider to move rectilinearly. One or more positioning grooves are disposed on the slider in parallel with the nut. Guide rails are correspondingly disposed in the positioning grooves. One end of each guide rail is fixed to the cabinet and the other end of each guide rail is fixed to a top stopper. Therefore, a better adjustability is achieved within a limited inner space of the furniture. Moreover, the drive does not need to move, and the stroke length of the drive is independent from the cabinet size thereof, so that the drive has a low manufacturing cost and is easily assembled.

An improved structure of linear actuator includes an actuator including a gear set having a friction portion located at the periphery of the gear shaft of a driven gear thereof, a one-way bearing mounted on the gear shaft for rubbing against the friction portion to brake the driven gear from reverse rotation, a driver for driving the gear set and a transmission mechanism including a lead screw coaxially coupled to and rotatable by the gear shaft of the driven gear and a retractable tube assembly coupled to the lead screw and movable by the lead screw between an extended position and a received position, and a stopping mechanism including a thrust bearing coupled to the gear shaft of the driven gear and stoppable against an inner race of the one-way bearing inner race to bear an axial thrust load.

An optical unit is disclosed which is capable of being easily assembled, enabling its optical element to smoothly move, and preventing friction loss from being generated around its nut member. A lens driving apparatus is provided for moving an optical element holder, which supports an optical element having an optical axis and is movable along a guide member, in an extension direction of the optical axis, using a nut integrally provided at the holder, and a lead screw threadedly coupled to the nut to rotate forward and backward by a driving unit. In the lens driving apparatus, the forward or backward rotation of the motor is transmitted to the lead screw via a reduction gear train. The lead screw is installed to be inclinedly movable with respect to the extension direction of the optical axis about threaded coupling portions of a threaded section of the lead screw and the nut.