Abstract: A modular refrigerating appliance comprising a first planar heat-insulating element and additional planar heat-insulating elements, which are joined to one another whereby being able to be detached from one another and which, when joined, form a housing of the refrigerating appliance. The modular refrigerating appliance also has a cooling circuit, which comprises an evaporator, a condenser, and a compressor, and which is mounted on the first planar heat-insulating element. At least the condenser is, at least in part, mechanically protected on its surface facing away from the first heat-insulating element solely by the construction of the first planar heat-insulating element.

Abstract: An dispensing system suitable for lifting and dispensing ice through the refrigerator compartment door of a bottom-mount refrigerator or lifting and dispensing ice from an undercounter ice maker to a dispenser on the countertop.

Abstract: Heating, ventilation, air conditioning, and refrigeration (HVAC&R) systems and heat exchangers are provided which include manifold configurations designed to promote mixing of vapor phase and liquid phase refrigerant. The manifolds contain flow mixers such as a helical tape, sectioned volumes, and partitions containing apertures. The flow mixers direct the flow of refrigerant within the manifold to promote a more homogenous distribution of fluid within the multichannel tubes.

Abstract: A conformable nosing device is described herein which conforms to have a bowed shape that substantially matches a bowed shape of a glass sheet and which engages the glass sheet to help minimize the motion of the glass sheet and to help reduce the stress within the glass sheet while the glass sheet is being scored and separated into individual glass sheets. In addition, the conformable nosing device can include a passive nosing device which can be controlled to further help minimize the motion of the glass sheet while the glass sheet is being scored and separated into individual glass sheets.

Abstract: A knitting machine with latch needles and without sinkers comprising, in regions of the needle holder comprised between two contiguous slots which accommodate a corresponding needle, a knitting retention element with a portion forming a stop shoulder for the knitting; the knitting retention element can move on command from a first position, of no interference with the knitting formed, to a second position, of it insertion with the portion between two contiguous needles in a region which faces the knitting forming plane, such as retain the knitting portion lying between two contiguous needles, contrasting the entrainment of the knitting along the needles during extraction motion of the needles from the needle holder to release, onto their shank, the previously formed loop of knitting and/or to engage the yarn delivered at a feed or drop of the machine.

Abstract: Gradient compression hosiery with therapeutic and aesthetic properties broadly includes a stocking section extending continuously between a distal end and an open proximal end thereof. The stocking section includes a tubular foot portion and a tubular leg portion. The stocking section is knitted at least substantially of a core-spun yarn with an elastomeric core and a twisted fiber sheath and includes elastomeric threads integrated into the stretch yarn knitting. The stocking section further presents a gradient region that extends from a distal location adjacent the distal end to a proximal location adjacent the proximal end, with a property of the hosiery changing progressively along the gradient region to provide compression that decreases progressively from the distal location to the proximal location when the hosiery is donned.

Abstract: An additive dispenser includes a fluid-retaining chamber. A siphoning post extends upward from a lower surface of the fluid-retaining chamber and cooperates with a cap or other structure so as to form a siphon chamber. When water is added to the chamber and a liquid level rises above an inlet to the siphoning element, a siphoning effect draws fluid from the chamber. When the siphoning effect is interrupted, any unsiphoned fluid remaining in the chamber exits by permeation through one or more porous elements located in a base of the chamber.

Abstract: The present application relates to lock assemblies that provide a secondary coupling point, utilizing an anti-rotation pin or extended tailpiece leg or other method, which rotationally couples the tailpiece to the cylinder plug, thereby preventing rotation of the tailpiece independently of the cylinder plug. Therefore, a tailpiece within a bolt cam or other actuator used to withdraw a bolt or unlock a lockset cannot be rotated after the tailpiece connector connecting the tailpiece to the cylinder plug has been forcibly removed, severed, or destroyed.

Abstract: A cylinder lock assembly includes a cylinder body and a plug assembly which is manufactured in a multiple of pieces to facilitate casting of each plug piece in a single operation. The plug assembly includes a plug body with a plug insert opening to receive a plug insert. The plug insert opening is generally L-shaped in cross-section to receive the plug insert which is correspondingly shaped. The plug insert includes a plug outer portion which defines an arcuate outer surface which corresponds with the outer circumference of the plug body when the plug insert is mounted therein. A plug pin chamber portion extends generally transverse to the plug outer portion to define a multiple of tumbler pin chambers which extend through the plug outer portion.

Abstract: A lock driving mechanism for use in a lock has an inner driving member having an inner panel, and an outer driving member attached to the inner panel and having an outer panel. The inner panel has an inner surface from which a lock core driver extends and connects to a lock core assembly of the lock and an outer surface on which an inner driver and an outer driver are formed. The outer panel has an inner surface on which an inner limiting protrusion and an outer limiting protrusion are formed, and an outer surface from which a latch driver extends to connect with a latch bolt of the lock. When a key inserted into the lock core assembly rotates, the inner and outer driver rotate, synchronously push the inner and outer bump, respectively, to make the key and latch driver rotate smoothly to drive the latch bolt to lock or unlock a door.

Abstract: A cylinder lock includes a sleeve having a plurality of locking holes, a key plug housed in the sleeve and having an output portion to output an interrupted motion of a clutch device by moving in an insertion and extraction direction by an insertion and extraction of a matching key, and a plurality of key matching members movably supported to the key plug, arranged to be insertable and removable in the plurality of locking holes respectively, and withdrawn from the plurality of locking holes respectively by an insertion of the matching key into the key plug.

Abstract: In a water diversion system, in a preferred embodiment, a first fold of a deflector is disposed into a first hanger cavity and a second deflector fold is disposed into a second hanger cavity. The first fold of the deflector cooperates with the first cavity of the hanger to allow a resistance hinge-like action of the deflector. The deflector may be lifted open by compression of a curve of the deflector to remove the second fold of the deflector from the second hanger cavity. Methods are provided in which, in a preferred embodiment, a deflector-forming machine is disposed above a trough-forming machine and the deflector-forming machine is moveable forward and backward relative to the trough-forming machine.

Abstract: An exemplary embodiment of the invention provides a method for producing an ultra thin wall metallic tube by cold working method with significant wall thickness reduction. In a method for producing the metallic tube with a cold pilger mill according to the invention, cold rolling is performed while tube diameters are being expanded using rolls having tapered groove dies whose calibers increase from an engaging entry side toward a finishing exit side. In a method for producing the metallic tube with a drawing machine according to the invention, cold drawing is performed while the tube diameters are being expanded using a solid die whose calibers increase from an engaging entry side toward a finishing exit side and a plug of a tapered mandrel bar whose diameters increase from an entry side of the die toward an exit side. In the metallic tube producing method, a maximum diameter of the plug or tapered mandrel bar may be larger than an outside diameter of the mother tube.

Abstract: The invention relates to a rolling device (1) comprising at least two working rolls (2, 3) which are respectively mounted in a roll stand (6) by means of working roll assembly pieces (4, 5). At least one of the working rolls (2, 3) is adjustable relative to the other working roll (2, 3) within the roll stand (6), especially in a vertical direction, so as to adjust a desired rolling gap. At east one working roll (2, 3) is effectively connected to bending means (7), with the aid of which said working roll (2, 3) can be impinged upon by a bending moment. The working roll assembly piece (4, 5) is provided with arms (9, 10) that laterally protrude relative to the axis (8) of the working roll (2, 3) to absorb the force generated by the bending means (7).

Abstract: A products having at least a portion thereof with a nanocrystalline microstructure, and methods of producing such products. The method generally entails machining a body to produce a polycrystalline chip having a nanocrystalline microstructure. The chips produced by the machining operation may be in the form of particulates, ribbons, wires, filaments and/or platelets. The chips may be consolidated (with or without comminution) to form a product, such that the product is essentially a nanocrystalline monolithic material consisting essentially or entirely of nano-crystals, or of grains grown from nano-crystals. Alternatively, the chips may be dispersed in a matrix material, such that the product is a composite material in which the chips are dispersed as a reinforcement material. According to a particular aspect, a monolithic article can be formed entirely from a single chip by deforming the chip and/or removing material from the chip.

Abstract: In a method or system for simultaneously forging parts, a forging die is provided with a bottom part and a top part, the forging die having a first forging cavity, a second forging cavity surrounding the first forging cavity, and a connecting opening between the first forging cavity and the second forging cavity. A billet is placed in a lower portion of at least one of the first forging cavity, the second forging cavity, and the connecting opening, and then with a forging press, the forging die is closed so that the die bottom part and die upper part approach one another to cause material of the billet to spread throughout the first forging cavity, the connecting opening, and the second forging cavity. The forging die is opened and a resulting unified forging part is removed formed of a first forging part, a second forging part, and a connecting region. The first forging part and the second forging part are separated at the connecting region.

Abstract: A method of forging a workpiece includes (a) incrementally advancing the workpiece in a closed die forge, the closed die forge including a stationary, flat die and a first split die including a plurality of first die segments, each die segment being incrementally advanced in sequence to contact the incrementally advancing workpiece; (b) replacing the stationary, flat die with a second split die including a plurality of second die segments; and (c) forging the workpiece forged in (a) between the first split die and the second split die, wherein the first die segments are stationary and at least some of the plurality of second die segments are incrementally advanced in sequence.

Abstract: Methods and systems for reducing the stress state of compressed ends of compressed tubes are disclosed. The methods and systems may provide a reduced tensile residual stress state, or even a compressive residual stress state. Tube products produced from the same are also provided.

Abstract: An improved crimping mechanism and method well-suited for use with stented prosthetic heart valves. The crimping mechanism includes a plurality of jaws configured for linear non-rotational movement toward a central axis. A rotational plate is formed with a plurality of spiral grooves or tracks for engaging the jaws. Rotational movement of the spiral tracks produces linear movement of the jaws. Nesting of the inner ends of the jaws permits each to be acted on along different radial lines while their inner faces move together evenly to reduce the crimping aperture in a smooth fashion. The crimping mechanism is particularly well-suited for use with stented prosthetic heart valves, such as a prosthetic aortic valve, though it can also be applied to other stented heart valves, venous valves, and even stent grafts which tend to be fairly large.

Abstract: A gun barrel stamping tool includes a die ram having a first U-shaped gun barrel fastener, a die container having a second U-shaped gun barrel fastener, and at least one die ram to die container fastener. The die ram and the die container each include opposing longer sidewalls and an elongate aperture located medially within each longer sidewall, the fastener being received by the elongate aperture. The die ram and die container combine to form an interior space for receiving a punch die. A circular aperture located medially within the shorter sidewall of the die container receives a punch die fastener for securing the punch die against the end wall of the die ram. The die container may include an adjustment mechanism for widening the interior space of the die container. The U-shaped gun barrel fasteners are located on opposing ends of the die ram and die container.

Abstract: A breath test simulator for supplying a breath test analyzer with a vapor including ethyl alcohol includes a heated thermal mass to heat an inlet passage.

Abstract: The invention generally relates to atomic resolution imaging, and, more particularly, to systems and methods for calibrating an atomic resolution measurement tool. A sample holder for holding test samples used in measuring linearity of an atomic force microscope is provided. The holder includes a body having a top surface, and a plurality of inclined regions formed in the body and spaced apart along the top surface. Each of the inclined regions is structured and arranged to hold a test sample used to measure linearity of an atomic force microscope at one of a plurality of predefined angles.

Abstract: Embodiments of the apparatus, systems, and methods relate to a photoacoustic cell including an excitation source, a chamber, and a quantum dot substrate between the excitation source and the chamber. The excitation source generates a light spectrum. The quantum dot substrate, when subjected to the light spectrum, emits a specific wavelength of light to be received by the chamber. The photoacoustic cell apparatus may be part of a portable gas sensing system, and may be used to detect and measure the concentration of one or more gases. Additional apparatus, systems, and methods are disclosed.

Abstract: A device for detecting chemical or biological substances includes an analytical instrument for detecting the substances and for providing information concerning the qualitative or quantitative presence of the substances, and also a contamination sensor for measuring the degree of contamination of the analytical instrument and/or of the device.

Abstract: A method and apparatus are disclosed for using an acceleration of a flow control system to determine the density of a fluid relative to the density of an in-line flow object.

Abstract: To detect a defect or failure of a compressed air load circuit in a compressed air system for vehicles, pressure is measured in compressed air load circuits and evaluated in an electronic control unit, which briefly shuts off the compressed air load circuits, measures pressure values and/or determines pressure gradients during the shutoff time and compares the pressure values and/or the determined pressure gradients with a respective threshold value, identifies defective circuits and definitively shuts off circuits detected as defective if the results are below the threshold value.

Abstract: Apparatus for remote inspection of fluid containers, e.g., portable tanks or fluid pipelines, includes an electronic circuit in communication between each container (or at various locations along a pipeline) and a remote central station. The electronic circuit is adapted to issue a wireless signal to the remote central station upon detection of predetermined internal conditions, such as an out-of-range pressure condition of fluid contained within the volume of the container, or upon detection of predetermined external conditions, such as the lack of presence of the container in its installed position or the presence of an obstruction to viewing of or access to the container.

Abstract: Methods and systems for constructing microfabricated devices including a microknife and methods and devices for a three-dimensional microstructure constructed from a plurality of separable planar components using one or more microfabrication techniques and optionally using one or more interlock structures.

Abstract: An evaluation method for pneumatic tires and a system thereof, is provided, capable of appropriately evaluating an adverse effect, such as deterioration, of tire temperature by expressing severity of a temperature imposed on a member of tire made of rubber or the like in quantitative and convenient manners. Detection counts are calculated for each detected temperature according to a detection counts calculating unit 102 based on information of temperatures of pneumatic tires detected by a temperature sensor of a temperature detector 101. Temperature severity numbers of the pneumatic tires are calculated from a computing equation by a severity calculating unit 104 based on the detection counts and contribution coefficients of deterioration of tire rubber with temperatures stored in a contribution coefficient storage 103 as parameters. Using the calculated temperature severity number, a determination unit 105 determines thermal deterioration of the tire.

Abstract: The present invention aims to coaxially aligning a tire with support rims with high accuracy by eliminating an effect of a tread outer surface. A radial inner end position of the bead portion of the tire his detected by a photoelectric sensor at circumferentially separated four points, and a deviation between the central axis of the tire and the central axis of a pair of support rims. The bead portion of the tire, which is an subject of the detection of the inner end position, is a portion where its dimension and shape are hardly changed even if the tire runs (i.e., is used) for a long time, so that the above-mentioned deviation can be determined at a high accuracy to, thereby, conduct a center alignment of the tire with the support rims at a high accuracy.

Abstract: A heater chip (4) as a heat generation element is secured to the surface on the periphery of piping (2). Further, a temperature sensor chip couple (6) is placed on the surface on the periphery of the piping (2), along the direction of flow of fluid flowing in the piping (2). One (6a) of the sensor chips in the couple is placed on the upstream side of the heater chip (4) and the other (6b) is placed on the downstream side of the heater chip (4). The heater chip (4) and the temperature sensor chips (6a, 6b) are formed in a chip type. The temperature sensor chips (6a, 6b) as the pair are placed at positions spaced by the same distance from the heater chip (4).

Abstract: A radar level gauge system, for determining a filling level of a product contained in a tank, the radar level gauge system comprising a transceiver including a signal generator for generating electromagnetic signals for transmission; a transmitter branch for transmitting the electromagnetic signals; and a receiver branch for receiving electromagnetic signals.

Abstract: The liquid depth sensing and identification system determines both the pressure head or depth, and therefore the quantity, of a liquid in a tank, as well as determining the characteristics of the liquid at the bottom of the probe. Two principles of operation are disclosed herein. The system may use a gas bubble collector about the outlet end of the purge tube, with the difference in height of the collector and purge tube mouths defining the very small difference in pressure head required to resolve the bubble emission characteristics produced in different liquids. Alternatively, the system incorporates a mass flow sensor capable of detecting minute changes in mass flow as bubbles are emitted from the purge tube in order to determine the type and characteristics of the liquid. The system operates using an open loop principle of operation, with no feedback provided to control the purge pump.

Abstract: The invention relates to a gas/liquid separator comprising a capacitive level sensor, which is particularly suitable for systems that employ reduced volumes of fluids at high pressures. The inventive separator includes a metal part comprising a borehole which is closed at the lower end thereof, such as to form a container. The aforementioned container comprises at least one gas inlet, one liquid outlet and one gas outlet. A cooling system in the form of a Peltier cell that is in contact with the walls of the metal part, generates the condensation of the liquid which is collected at the bottom of the container until the introduction of a probe, which is electrically isolated from the system and which forms an electric condenser with the walls of the part. The capacity of the condenser varies according to the level of liquid in the container.

Abstract: A rotation sensor has a substrate with a first surface and a second surface. A shear-wave transparent mirror is arranged on the first surface of the substrate, and a shear-wave isolator is arranged above the shear-wave transparent mirror, the shear-wave transparent mirror and the shear-wave isolator being arranged separated from each other to define a Coriolis zone there between. A bulk-acoustic-wave resonator is arranged above the shear-wave isolator, and a shear-wave detector is arranged on the substrate in a direction, in which a shear-wave generated by the bulk-acoustic-wave resonator upon rotation propagates.

Abstract: A method for operating a vibrating gyroscope and to a sensor arrangement comprising such a vibrating gyroscope, wherein the vibrating gyroscope is used as a resonator and is part of at least one control circuit that excites the vibration gyroscope by feeding an excitation signal with its natural frequency. An output signal can be tapped from the vibrating gyroscope from which the excitation signal can be derived by filtering and amplification. In accordance with the invention, once a sensor arrangement comprising the vibrating gyroscope is switched on, an initial value for the natural frequency is calculated from a previously measured value of the natural frequency stored in a memory and parameters that effect a modification of the natural frequency since start of the measurement, and the excitation signal is fed to the vibrating gyroscope with the calculated initial value of the frequency.

Abstract: A driver device includes a gain control amplifier that causes a vibrator to produce driving vibrations by controlling an oscillation amplitude in an oscillation loop, a signal generation circuit that generates a signal having a given frequency, and a modulation circuit that modulates the frequency of the signal generated by the signal generation circuit to a resonance frequency of the vibrator. The driver device causes the vibrator to produce the driving vibrations using the signal modulated by the modulation circuit, and then causes the vibrator to produce the driving vibrations by controlling the oscillation amplitude in the oscillation loop formed by the vibrator and the gain control amplifier.

Abstract: A computer implemented method, or hardware filtration apparatus, and computer usable program code for measuring porosity in materials. An ultrasonic signal is emitted from a transmitting transducer in an ultrasonic measurement system into a material. A response signal is received at a receiving transducer in the ultrasonic measurement system from the material. The response signal is filtered to pass only frequencies in the response signal within a selected frequency range to form a filtered response signal. A porosity level of the material is identified using the filtered response signal.

Abstract: A pressure sensor includes a housing, a pressure input orifice opened on a pipe sleeve formed on the housing, a diaphragm that seals the pressure input orifice and has one face as a pressure receiving face, a force transmitting unit connected to a central area of the other face of the diaphragm in the housing, and a pressure sensitive element whose detection direction of a force is a detection axis. A displacement direction and the detection axis of the force transmitting unit are roughly orthogonal to the pressure receiving face. One end and the other end of the pressure sensitive element are respectively fixed to the housing and the force transmitting unit with an adhesive therebetween, and the adhesive is an inorganic adhesive.

Abstract: A sensor assembly consists of a metallic pressure sensor cap welded to a tubular gland, which integrally forms a sealing edge on its one end opposing the pressure sensor cap side, a housing part, which has an opening formed therein such that the gland can penetrate the same, and a gland nut being turnably supported on a projecting portion of the gland for attaching the sealing edge to a process port. A stepped portion of the sensor cap is welded to a stepped portion of the gland, and the housing part is fixed to the outside surface of the gland in a position between the sensor cap and the sealing edge. Here, the sensor cap has an outer diameter, which is smaller than or equal to an outer diameter of the gland, so that the sensor cap being welded to the gland beforehand can be fitted into the opening of the housing part.

Abstract: A negative pressure gauge includes a body and a multi-stage positioning means. The body is provided with an airflow passage. The multi-stage positioning means includes a rotary piece and a cover plate. The rotary piece is pivotally connected to the body and is provided with positioning recesses and venting troughs. The cover plate covers the rotary piece and is fixedly connected to the body. The cover plate extends to form a positioning protrusion corresponding to the positioning recesses. When the rotary piece rotates with respect to the cover plate, the positioning recesses allow the positioning protrusion to be selectively positioned therein and control the communication or obstruction between the venting troughs and the airflow passage.

Abstract: A biomechanical system for testing a coupled joint is provided. The coupled joint has a fixed first end and a moving second end within the testing system. The testing system includes a servo actuation system operatively connected to the moving end. The system is able to impart at least four degrees of freedom to the moving end of the coupled joint. The testing system also includes a first force sensor disposed between the servo actuation system and the moving end of the coupled joint for sensing applied load, and a second force sensor disposed at the fixed end of the coupled joint for sensing transmitted load. The system also includes a controller for selectively directing input signals to the servo actuation system in order to apply selected forces and/or motions to the moving end of the coupled joint. The coupled joint may be a cervical spine specimen.

Abstract: The invention relates to a method of measuring a stress wave and to a measuring device and a rock breaking device. A percussion device (7) gives impact pulses to a waveguide (21), where a compression stress wave and a reflected tensile stress wave are generated, which propagate in the waveguide. The compression stress wave causes an extension in the waveguide and the tensile stress wave a thinning, in which case properties of the waveguide may be determined by measuring geometric changes in the cross section of the waveguide. The measurement data are utilized in controlling the rock breaking device.

Abstract: A pressing head structure (100) for testing key durability includes a pressing mechanism (10), a rubber head (40), a connecting mechanism (20) and a balance mechanism (30). The pressing mechanism includes a sliding rod (12) and a first spring (16). The first spring is placed over the sliding rod. The connecting mechanism connects the pressing mechanism and the rubber head. The balance mechanism is rotatably fixed to the connecting mechanism. The balance mechanism engages with the pressing mechanism. When the sliding rod moves down, the first spring and the balance mechanism together supply an unaltered resultant resistance in the moving direction of the sliding rod.

Abstract: An electromagnetic flow meter has a pipe body 16 in which a measurement target fluid flows. The pipe body 16 includes: a measurement pipe 1 having a groove 3 whose cross-section is any of a semicircular shape, a rectangular shape, and a triangular shape formed on an inner surface in a circumferential direction; and a resin lining portion 10a formed on the inner surface of the measurement pipe.

Abstract: A method and apparatus for determining at least one characteristic of a fluid flowing within a pipe is provided and includes at least one sensing device. The at least one sensing device includes a first sensor segment having a first segment polarity and being associated with a first outer portion of the pipe and a second sensor segment having a second segment polarity and being associated with a second outer portion of the pipe, wherein the first sensor segment and the second sensor segment generate sensor data responsive to the fluid flowing within the pipe. The apparatus further includes a processing device communicated with the at least one sensing device, wherein the processing device receives the sensor data and processes the sensor data to determine the at least one characteristic of the fluid.

Abstract: A multi-vortex flowmeter includes a vortex flowmeter for measurement by volume flow rate and a thermal flowmeter for measurement by mass flow rate to selectively use the two flowmeters according to the flow rate of fluid to be measured flowing through a flow channel. The multi-vortex flowmeter has a switching point between two flowmeters based on the mass flow rate. A mass flow rate Qm at the switching point in a range larger than the minimum flow rate of a vortex flowmeter and smaller than the maximum flow rate of a thermal flowmeter is determined by: Qm=K3*?P. Alternatively, a volume flow rate Q at the switching point in a range larger than the minimum flow rate of a vortex flowmeter and smaller than the maximum flow rate of a thermal flowmeter is determined by: Q=K1/?P.

Abstract: A flowmeter including a system chip with a silicon substrate provided on a carrier, in an opening whereof at least one silicon flow tube is provided for transporting a medium whose flow rate is to be measured, the tube having two ends that issue via a wall of the opening into channels coated with silicon nitride in the silicon substrate, wherein the flow tube forms part of a Coriolis flow sensor and/or a thermal flow sensor, and wherein the channels are preferably in communication through the carrier with connection lines to the external world.

Abstract: A sensor includes a shaft and a magnetic sensor. The shaft may have at least one magnetized active region. The magnetic sensor may be configured to sense a magnetic field about the shaft, and may provide an output representative of torque applied to the shaft, shaft rotational speed and shaft rotational position.

Abstract: In a method for measuring the tensile stress of a running web, force sensors (7) are connected in the form of a Wheatstone bridge (11). An amplifier (18) amplifies a diagonal voltage (17) of the Wheatstone bridge (11). In order to be able to detect whether at least one of the force sensors (7) is defective, the Wheatstone bridge (11) can be loaded using at least one resistor (26) by means of at least one switch (24, 25). Comparing the measured values, with loading, with the measured values, without loading, determines whether the force sensors (7) of the Wheatstone bridge (11) are functional. Otherwise, an active error signal (28) is output.