160results about How to "Prevent chatter" patented technology

An end mill including a cylindrical body having (a) flutes each formed in the cylindrical body and each extending from an axially distal end of the cylindrical body toward an axially proximal end of the cylindrical body, (b) peripheral cutting edges each provided by one of widthwise opposite edges of a corresponding one of the flutes, and (c) end cutting edges each located at the axially distal end of the cylindrical body and contiguous to a corresponding one of the peripheral cutting edges. The end cutting edges include first and second end cutting edges, while the peripheral cutting edges include first and second peripheral cutting edges which are contiguous to the first and second end cutting edges, respectively. A first axial rake angle of the first end cutting edge is smaller than a second axial rake angle of the second end cutting edge, while a first radial rake angle of the first peripheral cutting edge is larger than a second radial rake angle of the second peripheral cutting edge.

The nanometer vibration-reducing and noise-reducing self repairing material is prepared with nanometer level metal powder and natural ore powder as main material and through adding several kinds of supplementary material and certain technological process, and is added into lubricating oil or ultrasonic medium as high performance repair material. The present invention features that the high performance repair material can create high hardness self-repairing lubricating film fast on the surface of metal friction pairs to regulate the interval of the friction pair, reduce friction coefficient, raise bearing capacity, leveling the friction surface, reduce vibration and noise caused by the unbalance, friction and damage of the moving machine parts, and prolong the service life of the machine parts. The present invention may be used widely in improving performance of mechanical friction parts.

The invention relates to a drill tip (2) comprising a base body (6) having chip flutes (22A,B) and extending in the axial direction along an axis of rotation (8) and having at least two main cutting edges (14A,B) on the front face thereof extending outward in the radial direction to a cutting corner (16A,B). Seen in cross section, the base body is asymmetric relative to rotation about the axis of rotation (8) at the height of the cutting corner (16A,B). The cross section of the base body is simultaneously designed having symmetrical spacing from the main cutting edges (14A,B). The drill tip (2) is in particular designed as an interchangeable modular part of a modularly designed drill tip (5). A drill base body (4) in which the drill tip (2) can be inserted can therefore in turn be designed symmetrically.

A power-on reset circuit comprises a power supply voltage detection circuit that detects a rise of a power supply voltage and that changes a logic level of a first internal node; a capacitor charge / discharge circuit that charges and discharges a capacitor according to the first internal node level and that in an event that the power supply voltage is reduced, discharges the capacitor to follow the event; and a reset pulse generation circuit that before the power supply voltage rises higher than the predetermined voltage, outputs a first output voltage to an output node and that after the power supply voltage has risen higher than the predetermined voltage, outputs a second output voltage to the output node upon detecting that a charge level of the capacitor has become higher than a charge level detection voltage.

The invention discloses a non-smooth technique-based direct yaw moment control method of electric vehicles. By means of the method, the vehicle stability under extreme driving circumstances can be increased under the conditions of external disturbances and system uncertainty. The method comprises the following main steps: (1) building a linear two-degree-of-freedom vehicle dynamic model and a seven-degree-of-freedom whole vehicle dynamic model; 2, calculating the ideal yaw velocity and ideal side slip angle of the vehicles through the linear two-degree-of-freedom model, and constructing a state observer to observe the actual side slip angle of the vehicles; 3, designing a non-smooth control module controlled by yaw moment on the basis of non-smooth control technique; and 4, distributing the yaw moment by using a moment distributing module, thereby realizing the stable control of the vehicles. The method disclosed by the invention has the advantages that (1) the system has fast convergence performance and better disturbance-resistant performance; and (2) a chattering phenomenon is effectively avoided while good robust performance is obtained at the same time.

When a door sensor is touched, a vehicle-mounted unit and a portable unit performs mutual communications for authentication, and the doors are unlocked. When the door sensor is touched without intending to unlock the doors, wasteful consumption of electric energy is avoided which would otherwise result from mutual communications for authentication triggered by a request signal. When the door sensor may possibly be operated not for the purpose of unlocking the doors, e.g., when a CPU detects the doors as being already unlocked from a signal outputted from a door lock knob switch, a request signal is inhibited from being transmitted from the vehicle-mounted unit to the portable unit.

A vehicular illumination device includes a light distribution control unit, a determination unit and a control unit. The light distribution control unit performs an alteration control of a vehicular illumination unit so as to alter a light distribution with respect to an illumination object detected by a detection unit. When the illumination object ceases to be detected, the determination unit determines whether or not there is a need to maintain the alteration control in a current state. When it is determined that there is a need to maintain the alteration control in the current state, the control unit controls the light distribution control unit so as to maintain the alteration control in the current state.

The present invention relates to a device and method for providing precise temperature control using inexpensive temperature controllers and / or thermostats. Specifically the invention provides modifications to either a temperature controller and / or a thermostat that enables precise temperature control using inexpensive components. The series rheostat type differential eliminator (SRDE) is an inexpensive circuit that interfaces between a temperature controller and a thermistor or other temperature sensor element. The SRDE is essentially a circuit that switches the thermistor between a shunt and a rheostat in a manner that reduces or eliminates the temperature differential, while preventing the system from going into “chatter.” The heating resistor type differential eliminator (HRDE) is an inexpensive and simple circuit design that uses a thermostat and heating resistor to provide both direct and accurate temperature control for a heating and / or cooling control element, while also preventing the system from chattering. Either of these devices can be used with a temperature-controlled device for sleeping. Both the SRDE and HRDE embodiments reduce the temperature differential of simple automatic temperature controllers so that they are better capable of achieving precise temperature control.

The invention discloses an adaptive inversion integral nonsingular fast terminal sliding mode controller design method based on an extended state observer for mechanical arm trajectory tracking control. Firstly, in order to better reflect the state of the mechanical arm in actual work and improve the control precision, a LuGre friction force model is combined with a mechanical arm kinetic model. And a novel integral fast terminal sliding mode surface is designed on the basis, so that the convergence speed and the tracking precision can be greatly improved, and a reasonable saturation functionis designed for a singular item to avoid singularity. Due to the fact that external disturbance and system uncertainty are unknown, an extended state observer is adopted to estimate and compensate theexternal disturbance and the system uncertainty, and meanwhile buffeting can be effectively eliminated. The speed information of the mechanical arm joint can be obtained through the expansion observer, and therefore people only need to measure the position information of the joint through the encoder. And finally, a control moment is designed by using a backstepping method to realize global asymptotic stability based on the Lyapunov theorem.

A vane-type compressor includes: a cylinder block; a rotor rotating within the cylinder block; vane slots provided on the rotor; vanes each provided slidably within each of the vane slots; coil springs provided within the vane slots for pushing the vanes; guide pins each provided along each of the coil springs and directly fixed on the vanes or the rotor; and guide holes each provided for each of the guide pins and formed on the rotor or the vane. The guide holes are formed on the vanes in case where the guide pins are directly fixed on the rotor. Alternatively, the guide holes are formed on the rotor in case where the guide pins are directly fixed on the vanes. The compressor prevents chattering of the vanes and also prevents a complex structure and cost rise.

The disclosure allows a short runner valve or manifold tuning valve type manifold tuning device to retain sufficient force on the valve assembly in its closed state to eliminate any vibration or chatter from the system under normal engine operation. The disclosure also allows the device to be “pulsed” to the open or closed position; thus no electrical power is required to keep the system in one state. This is especially useful if activated times are extended due to certain engine operating conditions.

Upon self-alignment of a steering wheel of the present invention, a steering wheel body has its ring plane displaced toward the vertical plane by means of plastic deformation of the steering wheel core. There is located a switch operation portion in at least one of the two front spokes neighboring a front space inside the ring portion and generally symmetrically arranged relative to the boss portion. The cores of the front spokes are further provided at positions generally symmetric relative to the boss portion and to the boss portion relative to the switch operation portion with deformable portions, respectively, to be twist-deformable upon self-alignment.

The invention discloses an adaptive robust slip form control method for a hybrid robot used for automobile electrophoretic painting transportation, and belongs to the technical field of automobile electrophoretic painting. The method comprises the following steps that: firstly, aiming at the hybrid robot to adopt a Lagrange method to establish a kinetic model of the hybrid model for carrying out trajectory planning; then, on the basis of the kinetic model, designing an adaptive superhelix slip form controller, dynamically regulating a gain through an adaptive rule to avoid the selection of anoverhigh gain so as to inhibit slip form control buffeting; meanwhile, introducing a disturbance observer to estimate and compensate uncertainty in the hybrid robot and improve the anti-interference performance of the system; and finally, combining the disturbance observer with the adaptive slip form controller to form an adaptive robust slip form controller. By use of the method, the robustness and the anti-interference performance of the hybrid robot control system can be enhanced, in addition, the problems of slip form control buffeting and executor saturation can be solved, and the high-performance control of the hybrid robot used for automobile electrophoretic painting transportation can be realized.

A humerus implant for a reverse shoulder prosthesis has a cup shaped body and a thread at the outside of the body. The thread has a plurality of fins with cut-outs between the fins. At least one fin has an inclined leading surface which helps in incising into the bone by rotating the body in an inward direction. Furthermore, at least one fin has a forward oriented undercut trailing surface blocking rotation in the outward direction.

A main spindle of an air saw is reciprocated by sliding a piston in a cylinder chamber with the pressure of air supplied to the cylinder chamber via an air supply path so as to alternately apply the air pressure to pressure-receiving surfaces of a back plate and a front plate, wherein a rear air-cushion chamber is formed in a portion for fixing a return spring for urging the back plate toward the center of a cylinder while a front air-cushion chamber is formed in a portion for fixing a return spring for urging the front plate toward the center of the cylinder, so that the front and rear balance is maintained.

A magnetic sensor is provided. The magnetic sensor includes a magneto-resistance element. The magneto-resistance element includes an anti-ferromagnetic layer, a fixed magnetic layer being in contact with the anti-ferromagnetic layer, and a free magnetic layer. The free magnetic layer opposes the fixed magnetic layer via a non-magnetic layer interposed therebetween. The free magnetic layer has a magnetization direction that varies in accordance with an external magnetic field. The magneto-resistance element has a narrow and longitudinal shape and has an element length L greater than an element width W that is in the range of about 1 μm to 5 μm.

The invention discloses a fixed time dynamic surface high-order sliding-mode suppression method for chaotic oscillation of a power system. The suppression method comprises the steps of (1) determining the reactive power of the to-be-compensated power system; (2) establishing a mathematical model of a current source type static synchronous compensation controller, and determining the output and reference value of the current source type static synchronous compensation controller; (3) determining a control target value, wherein the output can achieve an adjacent domain with an arbitrarily small reference value within finite time, and the upper bound of the convergence time does not depend on the initial value; (4) designing a fixed time dynamic surface high-order sliding-mode surface and control law to realize target control; and (5) determining the control parameter of the designed control law according to stability analysis of the Liapunov function. By adoption of the method, system stability can be realized within predetermined time under any initial starting condition of the system; and in addition, a buffeting phenomenon is overcome, higher transient response is obtained, the convergence speed is accelerated and the stability of the power system is improved.

Disclosed is a hydraulic circuit for a pipe layer, in which the generation of hydraulic shock in equipment is prevented when an operating device or a moving device is finely operated during combined work in a pipe-laying operation mode. The hydraulic circuit for a pipe layer according to the present invention comprises a main control valve having a straight traveling valve and controls a discharged flow of a hydraulic pump by a negative flow control system, wherein the hydraulic circuit comprises: an unloading valve which linearly controls the closing of a passage of a flow that flows to a hydraulic tank from a center bypass passage of a hydraulic pump when an operating device or a moving device is finely operated during combined work; a pilot valve which is linked with a straight traveling valve, and supplies signal pressure corresponding to an operation signal of the moving device or the operating device to the unloading valve; and an operation mode switch valve which is switched during the combined work, and respectively supplies pilot signal pressure to the straight traveling valve, the pilot valve, and a valve spool which is installed on a downstream side of the center bypass passage of the hydraulic pump.

A damper assembly includes a fixed rack gear, a rotary gear damper having a gear engaged with the rack gear, and a tether movable with the damper along the rack gear and connected to the movable object to be controlled by the damper. A biasing element normally urges the damper away from anti-rotation locking members.

The invention discloses a self-adaption limited time command filtering backstepping control method of a multi-mechanical-arm system. The method comprises the steps of establishing a limited time command filter, a virtual control signal, a self-adaption updating rule, an error compensation mechanism and the like. By means of the method, the computing complexity problem caused by a traditional backstepping method can be avoided, and the effect that when a system contains uncertain parameters and unknown dynamic states, the set tracking error limited time is converged into an expected neighborhood can be guaranteed. In addition, errors generated by the command filter can be eliminated by utilizing an error compensation signal, and the control performance is further improved. Due to the fact that the virtual signal and the error compensation mechanism only use the neighborhood information of each mechanical arm, the method is completely distributed, and simulation results further indicatesthe effectiveness of the method.

A damper assembly includes a fixed rack gear, a rotary gear damper having a gear engaged with the rack gear, and a tether movable with the damper along the rack gear and connected to the movable object to be controlled by the damper. A biasing element normally urges the damper away from anti-rotation locking members.

The invention provides a finite time combination synchronization sliding mode control method for composite chaotic systems with uncertain parameters. The method comprises the following steps: A, as for three composite chaotic systems with uncertain parameters, the two serve as driving systems, the other one serves as a response system, subtraction is correspondingly carried out between the combination of the two driving systems and the response system, and a combination error system is obtained; B, a terminal sliding mode control plane is designed to enable the combination error system to achieve the designed sliding mode plane, three parameter control laws and a sliding mode control law in the finite time are designed, and realization of sliding mode control in the finite time of the combination error system is ensured; and C, finally, the three parameter control laws and the sliding mode control law in the finite time are loaded to the response system, and combination synchronization sliding mode control in a finite time on the three composite chaotic systems with uncertain parameters can be realized. Safety of secure communication is improved, and the control efficiency is greatly improved.

The invention belongs to the technical field of robots, and particularly relates to a movement decoupling hydraulic driving three-degree-of-freedom spherical wrist. The problems that the flexibility,the posture adjustment capacity and the precision positioning capacity of an end effector are conducted due to the fact that a wrist is complex in structure, incompact, small in power intensity, low in integration level and high in self weight, a transmission chain is long, and movement coupling exists are solved. The movement decoupling hydraulic driving three-degree-of-freedom spherical wrist comprises a rotation hydraulic motor, an angle sensor, a machine frame, a displacement sensor, a pitching hydraulic oil cylinder, a pitching ring, a side-sway end cover, a bearing, a transmission shaft,a transmission shaft coupler and a side-sway hydraulic oil cylinder. The pitching axis, the side-sway axis and the rotation axis of the movement decoupling hydraulic driving three-degree-of-freedom spherical wrist cross at one point, uncoupling of three active input movements including pitching, side-sway and rotation can be achieved, thus, the posture of the wrist is easy and convenient to control, the control precision is high, the posture capacity is high, and the mechanical arm vibrating phenomenon caused by movement coupling generated during joint matching adjustment is avoided.

Method, article of manufacture and system using minimum data to determine whether a sliding-mode control should be applied in a plant. First measure the plant in an open-loop control fashion, and using the measured data, describe a state equation of the plant by system identification and order determination methods. Then design a switching hyperplane for sliding-mode control. Next, calculate higher order statistics on the difference between an output of a linear model on the hyperplane and an output of the sliding-mode control model in the measured data; When any of the higher order moments is larger than a predetermined threshold, configure a controller as a sum of the linear control input term and the nonlinear control input term. If both higher-order moments are smaller than the threshold, then configure the controller using only a linear control input term.

A refrigerant system includes a compressor with a discharge valve that temporarily restricts the compressor's outflow at startup so that the discharge pressure can quickly rise to force lubricant back to the compressor. The discharge valve also helps prevent an axial face of a rotor of a screw compressor from rubbing against a bearing housing axial face of the compressor's housing. When the system turns off under certain low ambient air temperature conditions, the valve closes to help prevent the system's evaporator from freezing up. The discharge valve includes a novel arrangement of a piston, a valve stem extending from the piston, and a valve plug pivotally attached to the valve stem. The pivotal connection ensures a positive seal between the valve plug and a valve seat. A somewhat restricted fluid passageway between the valve's discharge chamber and piston chamber helps prevent the valve from chattering as the valve opens.

A dynamic baffle system for a magnetic separator includes a containment barrier secured to a frame and positioned between a rotary screen drum and a magnetic drum. The dynamic baffle system further includes a baffle configured to block an opening of the containment barrier. The baffle is movable between an open position in which media mixture is capable of flowing from the containment barrier to the magnetic drum and a closed position in which the media mixture is prohibited from flowing from the containment barrier to the magnetic drum and configured to evenly build up on the containment barrier. The dynamic baffle system further includes a sensor and a controller coupled to the sensor and the baffle to control the amount of media mixture flowing from the rotary screen drum to the magnetic drum.

A cam drive gear for an engine is described where the distance between the axes of a crankshaft and an idle shaft bearing an idle gear thereon can be made smaller, thereby contributing to a reduction in the size of the engine. In addition, a valve-operating system drive gear for an engine is also described where it is possible to restrain a cam chain from chattering at its portion wrapped around a drive sprocket.