摘要:
An optoelectronic triangulation sensor mounted adjacent a path of travel of a material web or individual paper sheets has a pivotable lever biased toward a fixed reference platen to bias the article(s) against the platen. The sensor light source is focused on a target carried on the back of the lever and reflected to a position-sensitive detector (e.g. lateral-effect photo-diode), the output of which varies in an analog signal in direct proportion to displacement of the lever. A relatively wide included angle between light source and PSD receiver shortens the range of the sensor and eliminates a need for pulse modulated light. The current driving the light source is monitored to emit a signal when the light source current exceeds a threshold, signaling the need for maintenance on the sensor such as cleaning the lens.
摘要:
A displacement gauge or gauge for detecting misalignment (3) employs four magnetic coils (24N, etc.) 90.degree. apart, (each) energized by an oscillator (36N, etc.), to sense the dislocation of a machine part, such as a post (12), near their center. A nominal position of the part (9 or 12) relative to a reference component (6) of the machine is first established. Subsequent displacements are detected and are indicated if they exceed a predetermined threshold magnitude.Signals from the four coils are combined in such a way that the magnitude of the radius of a displacement of the part (9 or 12) from the nominal position is ascertained approximately, irrespective of the direction of displacement from the reference part (6). The combination signal (at 64) is the greatest of (a) the absolute value of a north/south displacement signal, (b) the absolute value of an east/west displacement signal, and (c) 0.707 multiplied by a combination signal which is the sum of the north/south and east/west absolute value signals. During setup the gauge is self-aligning on the post.
摘要:
A proximity switch assembly (10) for signaling the location of a movable member (36) at either of opposite end limits of movement relative to a stationary frame (44, 46) includes a compact elongate housing (58) adapted to be mounted on the frame to extend along the path of movement of a power driven member (32), such as the piston rod of a hydraulic cylinder, which shifts the movable member between its end limits. The proximity switch is fixedly mounted in the housing and carries a switch actuating member (68) mounted for sliding movement over a relatively short distance sufficient to move an actuating target (74) into and out of actuating proximity of an air core proximity sensing coil (120) within the housing. Lost motion abutment shoulders (70, 72) on the switch actuation member and power driven member (54) move into engagement with each other as a power driven member approaches each end of its stroke.
摘要:
An optoelectronic position-sensitive detector (PSD) is disposed within a protective housing. An operator is movably mounted to the housing to be mechanically displaced by an object whose position is being sensed. A light projector within the housing is moved in response to operator movement to move a narrow light beam along a surface of the PSD corresponding to the position of the operator. A control system receives signals from the two output terminals of the PSD, compares and processes the same and produces a single analog signal indicative of the position of the object. The operator may be axially reciprocally movable or rotatable, and may have direct or indirect coupling with the light projector.
摘要:
An optoelectronic position-sensitive detector (PSD) is used with a light emitting diode (LED) in a through-beam photoelectric sensor application to detect the lateral position of an edge of an article or the lateral position or size variation of a thin object such as a small diameter fiber. The LED is offset toward one end of the PSD to establish a higher output signal at one end of the PSD than at an opposite end, thereby maintaining a positive output signal for the sensor. The LED and the PSD are potted with clear epoxy within holes in aluminum housing plates to provide RFI and EMI shielding.
摘要:
A controller for an electric clamp closes the clamp rapidly at first, then runs at a slower speed while contacting the workpiece, and speeds up again after contacting it, to close with full clamping force. Arrival of the clamp at the position for slowing down is directly detected by means of a proximity sensor, as are arrivals at other positions. The speed of operation is relatively insensitive to the voltage of its AC electrical power source because an open-loop compensating signal controls the pulse duration of rectified DC pulses that drive the motor. The controller has dynamic braking that is applied between individual pulses of pulse trains of motor current; this results in sigfificant increase in swings of current values for a given motor speed, that reduces harmful effects of mechanical friction. Two jogging speeds are selectable.
摘要:
A protective shroud (22) for a flexible electrical cable (20) at the location where it emerges coaxially from the rear end (14) of an electrical device, such as an inductive proximity or photoelectric sensor (2), serving as a strain relief and protection from being bumped as well as retaining such electrical cable (20) at a gradual right-angle bend from a horizontally-mounted sensor (2) to keep it out of the way, such as from the aisle adjacent a conveyer on which the sensor is mounted. Snap-in means including an annular groove (18) on the rear end of the sensor (2) and a constricted-opening (22f) slot (22e) in the inner side wall (22d) of the shroud (22) afford snap-in mounting of the latter onto the rear end (14) of the sensor (2) with the shroud (22) being rotatable thereon to allow the electrical cable (20) to be oriented in any desired direction. Another version of protective shroud (24) adapted for a vertically-mounted sensor ( 2) in FIG. 3 has its snap-in slot (24f) in its upper end wall (24e) so as to surround and protect the downwardly hanging cable (20) at the location where it emerges from the rear end (14) of the vertically-mounted sensor (2). The shroud (22,24) is mounted of plastic material of a selected color to identify the product of a particular manufacturer.
摘要:
A method and system is provided for assigning addresses to input/output (I/O) devices in a control network, and for verifying addresses assigned to the I/O devices. The system comprises a logic controller providing memory into which a connectivity map may be programmed. The connectivity map defines a specific expected address for each I/O device in the system. The logic controller further provides an external controller bus and logic for downloading the connectivity map to an I/O bus manager connected to the logic controller via the external controller bus. The I/O bus manager provides logic for assigning the specific addresses to the I/O devices. Network nodes connect the I/O bus manager to I/O cluster units in the system, each network node including a multiplexer for multiplexing output signals from the I/O bus manager and a demultiplexer for demultiplexing input signals from the I/O cluster units, the multiplexing/demultiplexing functions provided by a controller area network (CAN) integrated circuit. Each I/O cluster unit includes a multiplexer for multiplexing input signals from the I/O devices and a demultiplexer for demultiplexing output signals from its associated network node, the multiplexing/ demultiplexing functions again provided by a controller area network (CAN) integrated circuit. Each I/O cluster unit provides means for manually requesting address assignments and a visual indication of addresses so assigned. Each I/O cluster unit also provides means to manually reject the address assigned to it by the I/O bus manager if the assigned address is not the expected address for the I/O cluster processor defined in the connectivity map.
摘要:
Light emitting diodes of a through beam photoelectric detector are positioned in a door hinged to a sensor body in which the photodetector diodes are located. The light emitting diodes and photodetector diodes are aligned to establish photoelectric sensors when the door is closed upon the body. A base provides a receptacle for attachment of the sensor, the base having a plug-in electrical terminal half for receiving the connector prongs of a second half of the connector carried by the body. The connector is symmetrical so that the sensor unit may be installed to the base in either of two operating positions spaced 180 degrees apart to enable the hinge to be located at either the right-hand or left-hand side of the sensor unit and of the stations to be sensed. LED indicators for indicating the condition of the material being sensed at any of the stations are connected through printed circuitry to the connector half located within the base so that the indicators correspond to a particular sensing station regardless of the position of the sensor unit on the base.