Abstract: An electro-hydraulic forming tool is disclosed in which a membrane is retained between two volumes of liquid that are separated by a membrane. Electrodes are provided with a high voltage impulse to create a shockwave in one of the volumes of fluid that is transferred through the membrane to the other volume of fluid. The shockwave is transmitted to a blank that is formed into a one-sided die. The blank is formed against the forming surface of the die. Air evacuation means are provided to remove air from the upper surface of one or both volumes of liquid.

Abstract: A deep rolling roller head includes two housings for the deep rolling of the outer radii or fillets of split-pin crankshaft journals by means of two deep rolling rollers which are pressed into one of the two fillets under a rolling force while the crankshaft rotates around its axis of rotation. The two housings follow at the same time the different movements of the journals and support each other with their insides across from each other on a bearing plate. The insides of the housings bear on either side of the axis of rotation of the crankshaft and at a distance from it on an extension segment extending in the direction of the rolling force to below a contact point between the deep rolling rollers and the fillets to be deep-rolled. The bearing plate connected permanently to the inside and the extensions of one of the two housings.

Abstract: A rescue tool includes an elongate body and a pair of opposing arms. The arms include a first arm and a second arm that extend outwardly from the body. At least one of the first arm and the second arm is slidably coupled to the body. Each of the arms includes an inner face and an outer face, wherein at least one of the arm inner and outer faces includes a plurality of teeth. At least one of the first arm outer face and the second arm outer face includes a plurality of grooves defined therein.

Abstract: An easy open end for a container includes an end panel having a score defined therein that defines a removable end panel portion. The score is preferably notched to define a bottom edge having a continuous V-shaped recess. A first double fold is defined adjacent to and positioned radially inward from the score that defines beneath the score a first outwardly projecting extending cut protection bead. A second double fold is defined adjacent to and positioned radially outward from the score that defines beneath the score a second inwardly projecting cut protection bead. The end panel is elastically deformed in an area near the score so as to define a concave depression about the score, which provides enhanced cut protection.

Abstract: An electrical connector crimp die including a main body and an indicia forming section. The main body has a connector contacting surface between opposite ends of the main body. The indicia forming section is on the connector contacting surface. When the crimp die forms a crimp on an electrical connector, the indicia forming section is adapted to form an alignment indicia on the electrical connector for subsequent alignment of the die with the crimp to form a subsequent overlapping crimp.

Abstract: The inventive crimping tool (1) comprises a pushing head (2) which contact the fold (3) of a sheet (4) and has a front convex contour (5) in a plane view and a guiding seat (6) applicable to the sheet (4), wherein the pushing head (2) and the guiding seat (6) are remote from each other and define therebetween a groove (7) bounded by faces (8, 9) which are opposite in a substantially parallel direction with respect to the pushing head and the seat. The thickness (e) of said groove (7) substantially corresponds to the thickness of parts to be crimped, the front face of the pushing head is convexly connected to said flat face delimiting the groove and the bottom (10) thereof and extends along a convex contour, in particular substantially in a parallel direction with respect to the front face (5) of the pushing head (2).

Abstract: A breath simulator for supplying a breath test analyzer with a sample effluent of ethyl alcohol that controls headspace and adjacent effluent passageway temperature.

Abstract: A caliper atomic force microscope (AFM) comprises two AFM probes (each comprised of an oscillator and an attached tip) that operate on a sample in a coordinated manner. The coordinated operation of the AFM probes may be spatially or temporally coordinated. The result of the coordinated operation may be an image of the sample or a dimensional measurement of an unknown sample. The probes of the caliper AFM may be tilted, or the tips may be tilted at a non-orthogonal angle with respect to the probes, so as to enable the tips to access vertical sample surfaces or to enable the tips to touch each other. The tip shapes may include conical, boot-shaped, cylindrical, or spherical and materials from which the tips are fabricated may include silicon or carbon nanotubes. The oscillators may be beveled to allow the tips to operate in close proximity or in contact without interference of the oscillators. The disclosure of the present invention is discussed in terms of an atomic force (van der Waalls) interaction.

Abstract: The present invention provides a gas detection method and detection apparatus that provide better sensitivity and faster recovery after response than conventional gas detection methods and apparatus, by improving on these conventional methods and apparatus. The present invention is a gas detection method, in which the target gas is detected while oxygen is supplied to a sensor element 11a of a metal oxide-type gas sensor 11, wherein the target gas is detected while water vapor is supplied to the sensor element 11a, and is also a gas detection apparatus equipped with an oxygen supply means 14 for supplying oxygen to a sensor element 11a of a metal oxide-type gas sensor 11, said gas detection apparatus being provided with a water vapor supply means 15 for supplying water vapor to the sensor element 11a.

Abstract: A sensor is described for determining a physical property of a gas that is to be measured, especially the pressure, the temperature or the concentration of a gas component in the exhaust gas of internal combustion engines, which has a sensor element supported in a sensor housing whose gas-sensitive sensor section protrudes from the sensor housing, and has a protective tube that surrounds the sensor section. In order to achieve an effective protection of the gas-sensitive sensor section from water drops and solid substances included in the exhaust gas, in conjunction with cost-effective production of the protective tube, protective tube is developed spiral-shaped, yielding a tube wall that is spiral-shaped in cross section.

Abstract: A relaxation time constant associated with a fluid can be determined and then compared with a stored reference value. The difference between the relaxation time constant and the stored reference value can then be calculated in order to provide qualitative and/or quantitative data indicative of an adulteration of the fluid. The relaxation time constant associated with the fluid can be determined by first generating a static charge and then injecting the static charge into the fluid. The charge can then be collected from the fluid and utilized to determine the relaxation time constant.

Abstract: A system and methodology is provided for dynamically adjusting fluids that operate as a lubricant in a machine. The system includes a control module having a processor and one or more sensors providing data to the processor in situ with the machine, wherein the processor employs the data to monitor the fluid. One or more inputs are provided to receive a plurality of additives that are associated with the fluid, wherein actuators are employed by the processor to dispense the additives to the fluid. The processor dispenses the fluid based upon one or more parameters of the fluid.

Abstract: A method for sampling a host liquid in a vessel to detect the presence of an undesired liquid in the host liquid and removing host liquid that contains undesired liquid from the vessel, wherein an electrical capacitance probe is employed to detect the presence of the undesired liquid, and the liquid that is passed by the capacitance probe is fed to an incinerator.

Abstract: A low-cost artificial fingerprint liquid for quantitatively and with a good reproducibility evaluating an anti-staining property, and a fingerprint adhering property or a fingerprint removing property on the surface of an optical disk such as a reproduction-only optical disk, optical recording disk, magneto-optical recording disk, various displays such as a CRT, and various substances such as glass including a fine-particle-form substance and a dispersion medium capable of dispersing the fine-particle-form substance.

Abstract: There is provided an identification device capable of accurately, rapidly, and easily identifying a hydrocarbon-based liquid and alcohol-based liquid. An identification sensor unit (2) is arranged to face a flow passage (20) of a liquid to be measured and includes a liquid type detection unit with indirect heating (21) having a heating body and a temperature-sensitive body, and a liquid temperature detecting unit (22) for detecting the temperature of the liquid to be measured. The identification device further includes an identification calculation unit for applying a single pulse voltage to the heating body of the liquid type detection unit (21) so as to generate heat and identifying the liquid to be measured according to an output of a liquid type detection circuit formed by the temperature-sensitive body of the liquid type detecting unit (21) and the liquid temperature detection unit.

Abstract: A ball penetrometer probe for in situ measurement of soft soil properties, particularly in the seabed, comprises a spherical body and slender shaft assembly, and either individually or in combination, an anti-friction sleeve enclosing the shaft and/or a peripheral porous ring on the spherical body with connecting internal passages through the shaft assembly, the shaft being adapted to attach to an electronic transducer module. The ball penetrometer is deployed to penetrate the soil bed, to continuously measure the soil bearing forces resisting penetration and withdrawal of the ball, to optionally measure the pore water pressure of the soil in contact with the ball and to transmit the measurement data from the probe to a remote operating station, either by wireless means such as an acoustic transducer or via a wired electrical connection.

Abstract: The invention relates to a fuel supplying device comprising a low-pressure circuit, a high-pressure pump which is coupled to the low-pressure circuit on the input side thereof and transports fuel into a fuel accumulator, and an actuator which controls the fuel flow rate of the high-pressure pump. In the event of a stationary load, a first value of a fuel pressure and a first actuating signal of the actuator are determined, a second value of the fuel pressure is set, and said second value being larger or smaller than the first value of the fuel pressure by a pre-determined amount, a second actuating signal of the actuator is determined once the second value of the fuel pressure has been set, and an error in the fuel supplying device is detected according to the first and second actuating signals of the actuator.

Abstract: An apparatus for testing the brakes, wheel alignment, suspension, transmission, and engine of motorized wheeled vehicles, includes a dynamometer for self-calibration. A platform supports a road vehicle to be tested. Two or four pairs of short high-inertia rollers are revolvably supported adjacent to the platform, and positioned to individually support either the front wheels or the back wheels of the vehicle. The rollers are drivable by a stationary vehicle resting thereon, each pair of high-inertia rollers supporting one vehicle wheel. A floating roller contacts the wheel to detect side forces. Sensors are connected to the rollers and a computer for data processing, display and recording is connected to the sensors. Speed of the rollers is monitored by an encoder having a resolution of at least 1000 pulses/sec. A preferred embodiment of the apparatus includes electric motors which can be connected to drive the rollers.

Abstract: A test unit is electrically coupled between a motion controller and each of first and second redundant brakes. The test unit is responsive to the motion controller for automatically selecting one of the brakes to be tested. A microcontroller receives a signal from the motion controller that identifies one of the redundant brakes for activation, or deactivation, by an associated microcontroller output. The microcontroller outputs may be coupled respectively to activation terminals of respective brake switches connected in parallel to a brake activation voltage.

Abstract: The invention concerns a tire provided with a capacitative sensor including two substantially parallel electrodes, the sensor being carried by a sidewall of the tire. The electrodes of the sensor lie substantially in a plane perpendicular to the rotation axis of the tire and are substantially orientated in an ortho-radial direction. The invention also concerns a tire provided with a deformation sensor, a method for evaluating the deflection of a tire, and a deformation sensor.

Abstract: A tire pressure indicator that is combined with a fill valve. The indicator and the fill valve are coaxial or concentric. The invention may be screwed onto a tire valve stem. The indicator has three bands or sections, each of which is a different color, for indicating whether tire pressure is within a predetermined range, above that range, or below that range. The colors are viewed through a lens, aided by a mirror. A diaphragm pushes the indicator up when pressure rises, while a spring pushes the indicator down when pressure drops. A tire may be inflated or deflated while the invention is mounted on a tire stem. During inflation, the pin in an air chuck at the end of an air hose may depress a valve pin assembly to open the fill valve. A user may deflate the tire by manually depressing the valve pin assembly to release air.

Abstract: Disclosed is a method for measuring deformation of a turbine blade, the method including identifying at least one measuring point disposed on the turbine blade, retaining information pertaining to a first position of the at least one measuring point, operating the turbine blade over a period of time, measuring a spatial distance traveled by the at least one measuring point after the operating of the turbine blade over the period of time, the spatial distance being measured relative to the first position of the at least one measuring point; and determining an amount of deformation in the blade based on the measuring of the spatial distance.

Abstract: A mechanical load bearing indicator producing signals to a user when the user applies more than selected amounts of load between an extremity of the use and a surface. The indicator has a base plate adapted to establish a frame of reference with the surface, a load plate mounted for movement toward and away from the base plate and adapted to receive loads from the user's extremity, and at least two snap domes mechanically engaged between the base plate and the load plate for generating two signals when more than two different respective loads are applied to the load plate by the extremity. The domes are either in series between the plates or are together in a dual dome containing both, or are one or more stacks of domes which individually collapse under incremental loads which are added together to form the selected lower and higher loads.

Abstract: A positive displacement water meter includes a measuring chamber having an outlet port defined therein, wherein the outlet port includes a channel defined around the outlet port. A seal includes a planar surface and a curved surface, wherein the planar surface is substantially parallel to the curved surface, and the planar surface is situated within the channel. A meter casing includes an outlet port defined therein, wherein the meter casing receives the measuring chamber therein such that the outlet port of the measuring chamber is substantially aligned with the outlet port of the meter casing. The curved surface of the seal abuts a periphery of the outlet port of the meter casing forming a seal therewith. Due to the substantially arcuate cross section, the seal is adapted to resist the dislodging thereof from the channel during assembly of the positive displacement water meter.

Abstract: An isometric strength testing device includes a base for selectively supporting either a chair or a wheelchair for the subject to be tested. A pair of limb supports are positioned on the base, one to immobilize an arm and the other a leg of the subject. Each support includes a band carrying a load cell for generating a signal measurement of the force applied to the cell. Goniometers are associated with the supports for establishing appropriate angles of the subject's limbs at the knee and elbow. A computer connected to the force plates processes and displays data generated by the load cells.

Abstract: An instrument [particularly barometer ]movement includes a plurality of elements including a pressure transducer capable of sensing barometric pressure and converting the sensed pressure into electric signals, a stepper motor having an hour shaft used in a conventional quartz clock movement, a microprocessor, and a battery, operatively connected together so that the microprocessor controls movement of the stepper motor with power supplied by the battery in response changes in atmospheric pressure sensed by the pressure transducer; and a housing mounting the plurality of elements with the motor shaft extending outwardly from the housing. Other transducers, such as temperature or humidity, may alternatively be utilized. Other d.c. motors with positional feedback may sometimes alternatively be used in place of the stepper motor. The movement is operatively connected to a pointer (which may be much larger and heavier than in conventional analog instruments) which is accurately moved by the d.c.

Abstract: Operation of a planar resonator gyroscope with in-plane parasitic modes of vibration to obtain improved performance is disclosed. A planar resonator gyroscope, such as a disc resonator gyroscope, may be operated with embedded electrodes. The embedded electrodes may be disposed adjacent to the planar resonator and proximate to one or more anti-nodes of a parasitic vibration mode. A sensed amplitude of the parasitic mode is applied in differential signals used to operate the gyroscope. A feedback controller for damping the parasitic mode applies a drive voltage generated from the proportional voltage to one or more drive electrodes adjacent to the planar resonator disposed proximate to one or more anti-nodes of the parasitic vibration mode of the planar resonator. Parasitic in-plane modes may be thus damped in operating the gyroscope with active damping applied through an analog operational amplifier or digital feedback.

Abstract: An acceleration-triggered or shock-triggered, smart, tunable MEMS switch that may function as both a classic accelerometer and an acceleration threshold detector. A parallel element MEMS device has a stationary and a movable element forming a capacitor. Varying acceleration moves the movable member with respect to the stationary member, thereby changing the capacitance of the device. The capacitance varying may be used, in cooperation with appropriate circuitry, to provide a signal representative of instantaneous acceleration. By applying a biasing voltage, the movable element may be positioned in a predetermined fashion such that acceleration of a predetermined magnitude causes the movable element to pull in (snap down). The movable and stationary elements may function as a switch such that when the predetermined acceleration or shock level occurs, electrodes close, a current flows between the elements so that an external device such as an air bag may be activated.

Abstract: An aspirated smoke detector includes a flow path and a generator of acoustic waves in the flow path. Airborne particulate matter in the flow path responds to the acoustic field by particle agglomeration; the resulting larger particles flow into a photoelectric-type smoke sensor. A sensed level of particles can be processed, or compared to one or more predetermined thresholds to establish presence of one or more predetermined conditions.

Abstract: A method and apparatus for inspecting the walls of an underground pipe from inside the pipe in which an inspection apparatus having a circular planar platform having a plurality of lever arms having one end pivotably attached to one side of the platform, having a pipe inspection device connected to an opposite end, and having a system for pivoting the lever arms is inserted into the underground pipe, with the inspection apparatus oriented with the planar platform disposed perpendicular to the pipe axis. The plurality of lever arms are pivoted toward the inside wall of the pipe, contacting the inside wall with each inspection device as the apparatus is conveyed along a length of the underground pipe.

Abstract: The drop impact measuring system has i) a plurality of bimorph-type acceleration sensor containing a plurality of free vibrating sections each of which has individual draw-out electrodes; ii) a switch section for selecting output from the bimorph-type acceleration sensors; iii) an amplifying circuit for amplifying a signal applied via the switch section from the acceleration sensors; and iv) a logic circuit for logically evaluating the output from the amplifying circuit and controlling the switch section according to the result acquired from the logical evaluation.

Abstract: A micromechanical pressure sensor includes a substrate having a front side and a back side, the front side facing a medium and the back side being situated on the opposite side of the substrate. A sensor diaphragm having at least one sensor area is situated on the front side, and a recess or cavity is situated behind the sensor diaphragm, and electrical contacting is provided on the back side.

Abstract: An apparatus for monitoring fuel filter performance and transmitting performance information. The performance information may be transmitted wirelessly to a computer or a wireless telephone and then transmitted to a technician. The performance information is preferably transmitted with location information which identifies the location of the filter for which maintenance is required. The information may also be transmitted to a web server which can store the information in a database and also send information via text messaging or telephone voice transmission or other automatic electronic transmission mechanism.

Abstract: This invention relates generally to a micromachined acoustic transducer that has a scalable array of sealed cavities and perforated members forming capacitive cells that convert the electrical signal to acoustic signal or vice versa. It also relates to the method and more particularly to a micromachined acoustic transducer which includes a plurality of micromachined membranes and perforated members forming capacitive cells and more particularly to an acoustic transducer in which the capacitive cells are connected in a scalable array whereby electrical signals are applied to the said array and converted to acoustic signals. The transducer can either be used as an acoustic actuator or a microphone.

Abstract: A gauge pressure sensor apparatus and a method of forming the same. A constraint wafer can be partially etched to set the diaphragm size, followed by bonding to a top wafer. The thickness of the top wafer is either the desired diaphragm thickness or is thinned to the desired thickness after bonding. The bonding of top wafer and constraint wafer enables electrochemical etch stopping. This allows the media conduit to be etched through the back of the constraint wafer and an electrical signal produced when the etching reaches the diaphragm. The process prevents the diaphragm from being over-etched. The invention allows the die size to be smaller than die where the diaphragm size is set by etching from the back side.

Abstract: A semiconductor-based pressure sensor adapted for enhanced operation with controls electronics includes a pressure transducer having an output formed on a silicon die and an amplifier having an input and an output and fabricated on the silicon die next to the pressure transducer. The pressure transducer's output is provided to the amplifier's input via electrical connection. Output from the amplifier is connectable to a controller such as an ASIC.

Abstract: A connecting element for the releasable sealed connection of a fluid line system to a pressure transducer for detecting positive and negative pressures of a fluid located in the connecting element includes a housing, at least one fluid line connection, and a measuring chamber in the housing. The measuring chamber communicates with the fluid line connection, a diaphragm adjacent to the measuring chamber which is tightly connected to the housing for sealing the measuring chamber, and a connecting section on the housing. The connecting section being a repeatedly releasable connection of the connecting element to the pressure transducer. The connecting section has a tubular connection pointing away from the housing and having at least one locking element.

Abstract: A method of operating a take-up frame is disclosed herein. Specifically, a method of operating a take-up frame is disclosed which includes reading a force indication, wherein the force indication is obtained and provided through mechanical means. Additionally, the method includes adjusting the amount of force applied to achieve a desired amount of force.

Abstract: A method for reducing force and position control tracking errors caused by changes in hydraulic pressure at the actuator ports of a hydraulic servo valve. The method may use either the force command signal or the load cell signal in conjunction with a mathematical algorithm to compensate for changes in the flow capacity in the servo valve caused by changes in pressure at its ports. Good performance can be attained using the load cell signal. Alternatively, the algorithm can use the force command signal. The performance of the control loop with proper velocity feed-forward compensation keeps the feedback signal largely in phase with the command. Pressure sensors for detecting pressure changes at the actuator ports of the servo valve are not required for load droop compensation.

Abstract: A variable reluctance load cell for measuring the static or slowly fluctuating load, or tension, on devices is contained in a support tube. A sensor in the tube utilizes opposing C and I shaped magnetic cores attached to opposing ends of the support tube. A magnetic circuit is formed having an inductance defined by the size of the gap between the magnetic cores with the reluctance dominated by the gap. The sensor inductance is coupled with a fixed, predetermined capacitance in a resonant LC circuit, and the resonant frequency is a function of the gap. The sensor is in a cavity within the tube, and the cavity is sealed in a manner that prevents water or other damaging agents from entering the sensor. In this manner, mounting the sensor and tube to a static device and measuring the AC voltage at the sensor, the amount of load, or stress can be determined.

Abstract: A single drive shaft simulator and method is disclosed that allows up to four independent actions to be imposed on a test specimen such as an artificial joint specimen. These motions about mutually orthogonal axes are provided, and a constant compressive force and/or dynamic force may also be applied. The mechanical simulator is simple, accurate, and robust. The simulator assures synchronous movement where amplitude and profiles of the motion can be independently adjusted.

Abstract: A flow meter for a variable displacement compressor comprises a movable body operable to move by differential pressure, a magnet provided in the movable body, a magnetic sensor for detecting change of magnetic flux density of the magnet, a flow passage for refrigerant gas which is discharged from cylinder bores to flow therethrough, a sealed chamber connected perpendicularly to the flow passage and accommodating therein the movable body, an urging member for urging the movable body into the flow passage, a clearance formed between a movable body and an inner wall surface of the flow passage, a by-pass passage opened and closed as the movable body is moved in an axial direction of the movable body, and a communication passage for introducing into the sealed chamber the refrigerant gas in a downstream flow passage of the flow passage which is located downstream of the movable body.

Abstract: A mechanical torque wrench including a wrench body defining an elongated interior compartment and a wrench head including a bar extending therefrom being pivotally secured to a first end of the wrench body. A hand grip located on a second end of the wrench body, the hand grip being non-rotationally fixed to the second end of wrench body, and a set spring is disposed within the wrench body. A pawl is disposed between the bar and the set spring. Rotation of a dial screw in a first direction compresses the set spring and rotation in a second direction allows expansion of the set spring. A set ring is operatively connected to the dial screw and rotatable relative to the wrench body. A resistive element produces an output signal that depends on a position of the dial screw relative to the resistive element. A processor converts the output signal into an equivalent torque value in a selected system of units for display on a user interface.

Abstract: The present disclosure provides a device for sensing a torque applied through a shaft (18). The device includes a shaft (18) and a bearing (40) attached to the shaft (18). The bearing (40) includes an inner race (44), an outer race (42) and a plurality of rolling elements (46). A magnetoelastic ring (24) is press-fit onto the inner race (44). An eddy current or a magnetic field sensor (30) is placed in close proximity to the magnetoelastic ring (24). In the case of an eddy current sensor (30), the magnetoelastic ring (24) is not magnetized. In the case of a magnetic field sensor (30), the magnetoelastic ring (24) is magnetically circularly polarized. In either case, the chosen sensor (30) senses the induced changes of the magnetoelastic ring (24) characteristics and its associated electronics provides a measure of the applied torque.

Abstract: A method of fabricating a magnetoelastic torque sensor includes plating a magnetoelastic material to a magnetically inert substrate, and its endowment with uniaxial magnetic anisotropy through the creation within the transducer element of stress anisotropy. The plating of magnetostrictive material to the magnetically inert substrate provides a less expensive torque element that exhibits desired levels of accuracy and reliability.

Abstract: The Invention relates to a load cell which is designed to be coupled a flat belt-or similar-type elements for lifting elevators or similar. The inventive cell comprises a cell body (1) and a casing (2) which can be coupled to one another. According to the Invention the solid, metallic cell body support the corresponding strain gage. In addition, three cylindrical pivots (5) project out from the body, said pivots comprising a smooth outer surface and having a length that is adapted to the width of the lifting belt (9). One of the smaller lateral faces (6a) of the essentially prism shaped casing is open such that it can be coupled to the cell body. Furthermore, the upper and lower faces of the casing are provided with opposing openings for the passage of the lifting belt during the operational mounting of the cell.

Abstract: A newborn dummy used in a dynamic test comprises a head, a spine member including a neck member connected to the head, a trunk mounted on said spine member at a lower part of the neck member and provided so as to cover the spine member and spaced apart from the spine member. An abdomen pressure sensor is provided close to the spine member at a part corresponding to an abdomen in the trunk so as to be spaced apart from the trunk.

Abstract: The invention relates to a measuring sensor held under pre-stress for measuring forces and/or torques. In the inventive embodiment, a sensor is integrated into an adapter sleeve, which is configured in a compact manner in such a way that it is equipped with devices for connection to an adapter part and devices for fixing to a measuring component. The sensor is subjected to the required pre-stress by connecting the adapter sleeve to the adapter part. An amplification module can also be mounted in the adapter sleeve.

Abstract: A ball screw unit has a plurality of partition-rooms each of them accommodating a spacer ball interposed between two load carrying balls. The partition room is formed into two oblique frustum shaped recesses each of them extends a flared mouth tilted downwards to the longitudinal axis of the ball screw unit. The partition room is made of elastic polymer material to facilitate pushing the spacer ball into an oblate ellipsoidal hole opened on the partition room, and the hole is also communicated with the two recesses. With this structure, the spacer balls can be held stably in the partition rooms without the fear of escaping or occurrence of disorganized ball squeezing during operation of the ball screw unit. Besides, the dimension of spacer ball may be made as small as possible so as to increase the number of load carrying balls thereby resulting in improvement of load carrying capability of the structure.

Abstract: A multi-bit screwdriver comprises a housing with a bit chuck at the front end and bit assemblies retained within the housing. Each bit assembly has a tool bit at a front end and a contact surface at a back end. An actuator extends from each bit assembly for operative engagement by a user, for movement of the actuator and bit assembly between a forwardly extended in-use configuration whereat the bit assembly is positioned such that the tool bit extends outwardly from the housing, and the contact surface of the bit assembly is disposed in longitudinal force transmitting engagement against an abutment surface to preclude rearward movement of the bit assembly due to substantially longitudinally directed forces transmitted from the tool bit, and a retracted configuration whereat the contact surface of the bit assembly is removed in a lateral direction from the longitudinal force transmitting engagement with the abutment surface.