238 results about "Linear encoder" patented technology

The head/disk tester of the invention has a housing 43 that houses spindle 44 that rotatingly supports a magnetic disk 31. The housing supports a moveable carriage 30 that, in turn, supports a magnetic head 32. Positioning means 39 and 41 are used to move the carriage and the magnetic head across the magnetic disk. These positioning means include stepper motors that realize coarse positioning of the magnetic head, and a piezo actuator 37 that is used for fine positioning. Linear encoders 40 and 42 located at both sides of the carriage provide feedback information to a closed-loop positioning system that controls the piezo actuator. A set of special signals ("servo bursts") pre-written at a given track of the magnetic disk is used as an additional source of feedback information for the same closed-loop positioning system. This positioning system includes a servo analyzer 45 that reads and processes servo burst signals from the magnetic disk, and a position controller 49 that controls the piezo actuator. The controller contains two control loops: a proportional-integral-derivative (PID) loop and an additional servo burst loop. During any movement of the magnetic head to a prescribed command position, the servo burst feedback is turned off, and feedback from linear encoders is used by the PID loop to move the head. When the magnetic head reaches the prescribed command position, servo burst loop is turned on; it changes the command position of the PID loop in a way to keep the ratio of pre-written burst signals constant. As a result, the position of the magnetic head with respect to the data track remains the same for as long as necessary, even in unstable temperature conditions.

An inductive linear encoder (10) has a position sensor (1) and scale (2) which are movably disposed relative to each other. The sensor (1) is with a drive wire (3) to which an alternating current is supplied, and one set of detection wires (4a-4d) at right angles to the drive wire (3) in the same plane. The scale (2) is configured including an elongate substrate (7) having its surface on which a series combination of conductive closed loop patterns (8) are periodically arranged at equal intervals. These conductive closed loop (8) are linearly laid out on the substrate (7) in the relative movement direction. Each loop (8) consists essentially of a reception conductor segment (8a) and signal transmit conductor segments (8b, 8c) integral with the former (8a). The receive conductor segment (8a) is responsible for generation of an induced current due to a first variable magnetic field creatable from the drive coil (3). The transmit conductor segments (8b, 8c) are to create second variable magnetic fields that are opposite in polarity to each other and are perpendicular to the first magnetic field. Creation of such second magnetic fields results in flow of an induced current in the detector wire (4) of sensor (1), which in turn acts as a position detection output current.

The invention provides a speed detecting method of a moving body and a device thereof. In the lift using terminal floor reduction device, the device is able to obtain the necessary overspeed detecting response time near the terminal floor by the speed detector equipped in the lift car without using the linear coder having high position resolving capability. The position differential value from the linear coder and the acceleration integral quantity from the acceleration sensor are combined into speed value to carry out the overspeed judgment. The acceleration integral quantity is reset and differed at pulse edge of the linear coder. The necessary response time detecting the overspeed near the terminal floor is improved, and the speed needed by the terminal floor reduction device is accurately processed.

The invention discloses a real-time catheter intervention information measuring device in a cardiovascular interventional operation. The information measuring device comprises a six-dimensional force sensor, a linear encoder and an angle photoelectric encoder. In the operation, a catheter penetrates through the six-dimensional force sensor, and is connected to a force bearing end of the six-dimensional force sensor in a clamping manner through a clamping device; when an operator clamps the catheter to contact with a vessel wall through a clamping shaft, the resistance and the resistance moment between the catheter and the vessel wall can be measured in real time through the six-dimensional force sensor; when the operator operates the catheter to rotate axially through the clamping shaft, the rotary angle can be measured through the angle photoelectric encoder; and when the operator operates the catheter to move forwards or backwards through the clamping shaft, the number of grating pulse is counted by a reading head to measure the displacement in real time. By the information measuring device, information monitoring during the operation can be realized, safety of the operation can be improved, and quantitative data are provided for evaluating a virtual operation training system.

A linear motor includes a frame linearly extending in a longitudinal direction and having a channel-shaped cross section. The frame has sidewalls and a bottom wall that define a channel. A core is disposed on each of the side walls of the frame. An armature-side block is disposed in the channel of the frame. The armature-side block has a plurality of armatures, each of the armatures having two end surfaces at positions opposing to the cores provided on the side walls of the frame. One linear guide is disposed between the frame and the armature-side block. The linear guide has a rail fixed to the bottom wall of the frame and a slide block fixed to the armature-side block, such that one of the frame and the armature-side block is linearly movable relative to the other. A linear encoder having a linear scale and a sensor spaced a distance from the linear scale are disposed within the channel of the frame.

A movable member is moved in a preset direction in a linear motor. A characteristic-change position-detecting unit detects a position where the magnetic characteristic of the magnets has abruptly changed. The position detected is used as an origin-setting reference position. A reference position for the absolute position of the magnetic linear encoder is set based on the reference position.

A sealed linear encoder for determining the relative position of a first object and a second object. The sealed linear encoder includes a scale unit arranged in a hollow body that is mounted to a mounting structure associated with the first object and includes a slot which extends in a direction of measurement. A scanning unit for scanning the scale unit and a carrier connected to the second object, wherein the carrier extends through the slot. Sealing lips arranged at the hollow body and abutting the carrier so as to seal the carrier and a cover form-fitted to the hollow body for covering at least the slot.

A fastening device for a casing of a linear encoder belongs to the technical field of optics and is used for firmly fastening the casing to a part to be detected, and for effectively controlling deformation of the linear encoder upon temperature effect to be within a small range so that the linear coder has certain repeatable temperature property. The fastening for the casing of the linear encoder comprises a rigid casing support and a plurality of flexible casing supports, wherein the rigid casing support is fixed in the middle of the casing, and the flexible casing supports are fixed at equal intervals on the casing and disposed on two sides of the rigid casing support in bilateral symmetry. The rigid casing support is provided with a pin hole in the middle, each flexible casing support is provided with a through hole in the middle, and each flexible casing support is provided with grooves which are reserved on two sides of the through hole in bilateral symmetry. By the aid of the designed structure of the rigid casing support and the flexible casing supports, the deformation of the linear encoder upon temperature effect is controlled well, and the certain repeatable temperature property of the linear encoder is realized.

A source channel encoder, source channel decoder and methods for implementing such devices are disclosed herein. The source channel encoder includes a linear transform encoder configured to generate a plurality of source components. A successive refinement quantizer is configured to generate a plurality of bit planes based on the source components. A systematic linear encoder configured to map the bit planes into channel-encoded symbols. The linear transform encoder may be configured to apply a Discrete Cosine Transform (DCT) or a Discrete Wavelet Transform (DWT). The linear transform encoder may be configured for differential encoding.

This invention is an apparatus consisting of components that can be assembled and reassembled in various configurations allowing students to perform multiple physics and engineering experiments, with sensors and electronics integrated into the apparatus that allowing extraction of data via integrated data links, while computing and displaying results graphically in near real time. The principal component of the system is a linear drive system with a movable carriage, the position of which is measureable by various rotary and linear encoders. Load cells are able to measure forces of compression and tension. Temperature and Pressure sensors are able to measure gas pressure and the thermal conductivity of materials. The various components of this flexible educational tool can be disassembled and stored in a portable “toolkit”, the size of a small briefcase.

In electronic component mounting equipment, a nozzle mechanism is constituted by disposing a shaft type linear motor vertically above a nozzle unit and disposing a linear encoder vertically above the shaft type linear motor so that it has a slim shape. Consequently, occupied area of each nozzle mechanism can be reduced in the XY direction (horizontal direction), a pitch between adjoining nozzles can be made smaller, and a smaller mounting pitch in electronic components on a miniaturized, high-integration substrate can be dealt with.

To provide a linear encoder including a scale unit and a slider that slides along the scale unit, wherein the slider includes a slider enclosure including a slider holding unit, a detection head holding unit mounted inside a scale enclosure of the scale unit, and a pillar extending between the outside and inside of the scale enclosure to connect these two holding units, and a part of the pillar closer to the detection head holding unit and a part of the detection head holding unit closer to the pillar are bored by a thickness larger than a thickness of the pillar.

A movable positioning apparatus for positioning a work piece, which includes a base having linear motors attached thereto for supporting and moving a stage or work piece in a longitudinal direction relative to the base. The apparatus includes two linear encoders to measure rotation error by calculating the difference in measured positions. An alignment laser measures straightness errors. Two slides control yaw by moving in opposite directions, and the slides control straightness by moving in the same direction.

A bearing providing at least an inner ring and an outer ring adapted to concentrically rotate with respect to one another, equipped with at least one embedded device for the detection of a displacement in translation of the rings relative to each other, the detection device including a linear encoder element mounted on one of the rings, and a sensor element mounted on the other ring and opposite the encoder element.