Abstract: A splice protection system including a water resistant material disposed on a flexible wrapper that retains the water resistant material is disclosed. The splice protection system is useful for preventing unwanted entry of external elements into the splice regions of signal transmission devices, thus preserving the integrity and function of the signal transmission devices.

Abstract: A method of cable assembly with electromagnetic interference protection and a structure thereof are described. The cable comprises a transmission cable, a ground cable, and metal rings. The transmission cable connects the liquid crystal display and a motherboard of a notebook computer. The insulating cover of the ground cable is peeled off in at least one position of an insulating cover and exposes an internal conductive wire. The exposed positions correspond to positions of clips of the notebook computer. The conductive wire and the transmission cable are clamped in the metal rings, and therefore the electromagnetic interference noises transmit to a ground of the notebook computer.

Abstract: A physiological effect device comprising an elongate flexible member, band or strip having a magnetically inductive core around which is coiled at least one insulated electrically conductive wire. The conductive wire can act as a solenoid and utilise the small electrical pulses normally sent around or through a subject (such as an animal) wearing the device and thereby induce a (therapeutic) magnetic field in the core. The device may provide a useful induced magnetic field for physiological effects even when at rest and/or may absorb electrical pulses (such as those associated with pain in an animal). The device may further be arranged to absorb or screen radiation (such as microwaves or the like).

Abstract: The invention provides a communications cable comprising a plurality of cores through which communications signals can be transmitted, each core comprising a metallic conductor surrounded by a close-fitting sleeve of insulating material which is substantially free of halogenated polymers, the insulating material having a permittivity of no greater than 3, and comprising an outer layer of a non-foamed polymer surrounding a layer of foamed polymer, the outer layer containing a fire retardant, the layer of foamed polymer optionally surrounding a layer of non-foamed polymer, and wherein the region of the insulating material immediately adjacent the metallic conductor contains no fire retardant metal hydroxide and/or carbonate filler; an outer cable sheath disposed radially outwardly of and surrounding the cores, the outer cable sheath constituting a fire protection layer and being formed from an extrudable polymer containing a fire retardant material such as a metal hydroxide and/or carbonate filler; and optional

Abstract: A low cost, high performance flexible reinforcement member that can be used for both optical and copper communications cable. The reinforcement members made according to the preferred process are more rigid than known reinforcement members, but are less rigid than glass pultruded rods. Communications cables utilizing these members are lightweight and exhibit an improved combination of strength and flexibility compared to traditional communications cables. Further, these communication cables may then be installed into underground ducts using more economical and faster installation techniques.

Abstract: A low cost, high performance flexible reinforcement member that can be used for both optical and copper communications cable. The reinforcement members made according to the preferred process are more rigid than known reinforcement members, but are less rigid than glass pultruded rods. Communications cables utilizing these members are lightweight and exhibit an improved combination of strength and flexibility compared to traditional communications cables. Further, these communication cables may then be installed into underground ducts using more economical and faster installation techniques.

Abstract: A low cost, high performance, low profile flexible reinforcement member that can be used for both optical and copper communications cable. The reinforcement members made according to the preferred process are more rigid than known reinforcement members, but are less rigid than glass pultruded rods. Communications cables utilizing these members are lightweight and exhibit an improved combination of strength and flexibility compared to traditional communications cables. Further, these communication cables may then be installed into underground ducts using more economical and faster installation techniques.

Abstract: An electrical cable (K) has at least two strands (1) consisting of insulated conductors (2) stranded together. Insulation on the strands (1) consists of an inner layer in contact with the conductor, and which is softer than an outer layer. The strands (1) are surrounded by an inner sheathing (6). The cable (K) also has an electric shield (7) and an outer sheathing (8). A separator layer (5) is between the strands (1) and the inner sheathing (6), consisting of an inner layer (6a, 6b) fixedly joined together with an outer layer (6b). The inner layer (6a) facing the strands (1) is softer than the outer layer (6b), having an approximately circular peripheral surface and in firm contact with the separator layer (5) or the strands (1). The electric shield (7) consists of at least one essentially closed tubular metallic layer and a stranded layer and/or braiding of metallic wires in contact with the metallic layer.

Abstract: A wire separator capable of maintaining wires in a fixed bundle. The wire separator comprises an inner member having a plurality of apertures into which wires may be positioned via a plurality of gaps in the inner member. The wire separator also comprises an outer member capable of attaching to the inner member. Furthermore, the outer member has a slot. When the outer member is in a first position, the slot misaligns with the gaps, thereby maintaining the wires in the inner member and inhibiting wires from inadvertently falling out. In a second position, the slot aligns with at least one of the gaps to thereby facilitate quick removal or insertion of a wire into the wire separator while the other wires remain securely enclosed within the wire separator. Also, the same outer member can attach to different inner members with different numbers of apertures to advantageously reduce costs.

Abstract: A low cost, high performance flexible, rodent resistant reinforcement member that can be used for both optical and copper communications cable. The reinforcement members made according to the preferred process are more rigid than known reinforcement members, but are less rigid than glass pultruded rods. Communications cables utilizing these members are lightweight and exhibit an improved combination of strength and flexibility compared to traditional communications cables. Further, these communication cables may then be installed into underground ducts using more economical and faster installation techniques.

Abstract: In the present invention an electronic package assembly includes an integrated circuit positioned on a substrate. The substrate has substantially horizontal layers including horizontal signal wires having vertical thicknesses and resistance. In a preferred embodiment, first and second vertical thicknesses of the signal wires alternate from the top to the bottom of the substrate such that the signal wires with greater vertical thicknesses have lower resistance than the signal wires would typically have. A plurality of substantially vertical conductive vias traverse the horizontal layers such that the vertical conductive vias connect to the integrated circuit and connect with at least one of the horizontal signal wires. A circuit board positioned beneath the substrate includes connection members for connecting with, and terminating the vertical conductive vias.

Abstract: A circuit board includes a substrate having a top surface and a bottom surface and including circuit patterns disposed on the top and bottom surfaces thereof, the substrate defining a connection hole therein; an upper terminal electrically connected to a circuit pattern formed on the top surface of the substrate; a lower terminal electrically connected to a circuit pattern formed on the bottom surface of the substrate, the lower terminal being located opposite to the upper terminal; and wherein the upper terminal and the lower terminal are bonded inside the connection hole of the substrate for electrical connection there-between. A method of fabricating the circuit board is also disclosed.

Abstract: A transmission line includes a transmission line substrate, a signal line, and a first ground pattern that is provided on the transmission line substrate and is located between the transmission line substrate and a metal wire used to connect the signal line to a component.

Abstract: An apparatus and method for determining at least one downhole formation property is disclosed. The apparatus includes a probe and a pretest piston positionable in fluid communication with the formation, and a series of flowlines pressure gauges, and valves configured to selectively draw into the apparatus for measurement of one of formation fluid and mud. The method includes performing a first pretest to determine an estimated formation parameter; using the first pretest to design a second pretest and generate refined formation parameters whereby formation properties may be estimated.

Abstract: A downhole drilling apparatus suspended by tubing includes a drill bit driven by an electric motor powered by a cable means. The motor is mounted upon a hollow shaft which allows fluid to pass through, so that a fluid circuit along the tube and back along the annulus between the borehole and the tubing via the drill bit is.established. The state of the motor, particularly its speed and torque, can be monitored, and the motor may then be regulated as a result of the this data. Various sensors may be included in the drilling apparatus, and the data gathered similarly used to regulate the motor. Thrust means are included to urge the drill along the borehole. Supplementary pumps may be provided to assist the fluid flow. Both the thrust means and the pumps may be controlled by the control means.

Abstract: A method for drilling a borehole, comprising transmitting a directional signal to a downhole processor, and maintaining the desired drill bit azimuthal direction by using the downhole processor to evaluate an actual drill bit azimuthal direction relative to the desired drill bit azimuthal direction, and using the downhole processor to adjust the actual drill bit azimuthal direction by controlling the directional drilling device.

Abstract: A two stage filter for drilling fluid using downhole tools filters solid materials from the drilling fluid and has a first, outer filter section and a second, inner filter section. A portion of the drilling fluid flowing through the first section is received by the second section, and passed on to the fluid using device of the tool. A flow area of the first filter section is greater than a flow area of the second filter section.

Abstract: A male portion for percussive rock drilling includes sections of reduced cross-sectional area. At least one thread for percussive rock drilling is provided at an end of the male portion. The end of the male portion comprises an abutment surface for the transfer of impact waves. The length of the portion is defined as the length of an imaginary cylinder from a plane of the impact surface to a point where the plane ceases to contact a crest of the thread, wherein the length divided by the external diameter of the cylinder lies within a range of 1-2.

Abstract: The invention comprises a balance (1) with at least one digital weighing cell (2, 3, 4, 5) and an evaluation unit connected to the balance. The digital weighing cell (2, 3, 4, 5) is provided with memory elements (12, 13, 14, 15) in which the weighing cell parameters and the system parameters of the balance (1) or code numbers formed thereof are stored in an unmanipulatable manner by known methods such as audit trail counters, for example. The evaluation device is embodied as a program controlled data processing device (7) and is directly connected to the balance (1) or weighing cells (2, 3, 4, 5) provided therein. The measured data of the digital weighing cells (2, 3, 4, 5) which are calibratable and/or not calibratable are read out by the program-controlled data processing device (7) during each weighing process (7), in addition to the stored weighing cell parameters and system parameters of the balance (1) or the codes formed thereof.

Abstract: An apparatus and technique that extend the useful weighing range of a weight scale is provided. A preferred embodiment comprises a screw and a moveable weight. A head of the screw fits into a notch on the weight scale and the location moveable weight is varied in relation to the screw head by driving the screw into or away from the center of the moveable weight via a tapped receiver of the moveable weight. In a second embodiment, a supplemental weight has a base and a movable weight that are associated and positionally adjustable along at least one linear axis. In a preferred embodiment, a threaded screw length is used to adjust the relative positions of the base and the movable weight. The supplemental weight is removably coupled with the weight scale and calibrated into an operating state, wherefrom the weighing range of the scale may be extended.

Abstract: A bipedal robot of the present invention has a trunk consisting of an upper trunk and a lower trunk which are rotatable around a rotation axis relative to one another. The upper trunk has shoulders on the right and left sides. An arm is provided at each shoulder. A pair of right and left legs is attached to lower ends of the lower trunk. A storage battery is mounted to the back of the upper trunk, positioned within a shoulder width. The storage battery is positioned below the top of a head mounted on the upper trunk. When the robot walks a narrow passage or corridor having a width slightly larger than the width thereof, for example, this arrangement prevents the storage battery from interfering with the passage or the like.

Abstract: A steering mechanism of an electric car including tandem wheel suspensions and steering means for each pair of right and left wheels is provided in order to perform a smooth turning motion.

Abstract: A power split hybrid wheel drive system of the present invention comprises a planetary gear train (16) coupled to the output shaft of a driving engine (12). A primary motor or generator (18) is coupled to an output shaft of the planetary gear train (16) for receiving power therefrom, and a secondary motor or generator (30, 32) is associated with each driven vehicle wheel (14) to provide an electrical power pathway. A mechanical differential gear train (20) is coupled between the output shaft of the planetary gear train (16) and each driven vehicle wheel; (14) to provide a mechanical power pathway, while a mechanical clutch (22) and brake system (24) is configured to regulate the mechanical power routed to the differential gear train (20). A control system (48) is included to regulate the flow of electrical power between the primary motor (18) and secondary motors or generators (30, 32).

Abstract: An engine is connected to front wheels via a primary motor, a clutch and a transmission, and a secondary motor is connected to rear wheels. A vehicle is driven by the secondary motor while performing a combustion suspended idle operating condition in which the engine which has been brought to a combustion suspended condition is run idly by the primary motor according to driving conditions of the vehicle. The necessity for idling the engine is obviated so as to reduce the fuel consumption. Further, the engine can also be started up in quick and secured fashions by resuming the control of fuel supply and injection to the engine which is being run idly with its combustion being suspended and driving the primary motor while reducing the consumed power to a minimum level by reducing the load of the primary motor which runs the engine idly with its combustion being suspended.

Abstract: A drive assembly including an electric motor and frequency variable generator for use with a multi-axle vehicle. The vehicle generally includes an engine driving a first axle and a drive assembly with an electric motor driving a second drive axle. The drive assembly includes a frequency variable generator with an input shaft driven by the engine and the electric motor electrically communicates with the generator to receive output power from the generator. Other details of selected embodiments of the invention include the frequency variable generator having a rotor coupled to rotate with the engine output shaft and a stator electrically connected to the electric motor. An inverter is electrically connected to an electrical power source, such as a battery or the frequency variable generator, as well as to the rotor. A controller communicates with the inverter and is configured to control the magnitude and frequency of the power communicated from the inverter to the rotor winding.

Abstract: A parking pawl is implemented on a series type, hybrid electric vehicle using a pair of parallel worm gear rollers. The worm gear rollers are placed on opposite sides of a transmission gear from one another and mounted for rotation along their major axes allowing the worm gear rollers to be rotated to present either a planed side or a threaded section to the gear. The gear is circumferentially slotted to cooperate with the threaded section of the rollers to prevent rotation of the gear, but to turn freely when the planed faces of the worm gear roller are adjacent the gear.

Abstract: A partition for adjusting noise emanating from the engine compartment of a vehicle. The partition is provided for installation over the engine compartment of a vehicle and may comprise an opening integrally formed therein, a conduit communicating with the orifice, and a movable panel, the movable panel being operatively connected with the conduit. The panel can be moved manually or by mechanical or electrical remote actuation. The partition can be light transmissive, and a light source can be disposed proximate to the partition for illuminating the engine compartment.

Abstract: A ground effect vehicle apparatus comprising a vehicle body of integral and contiguous construction including a medial portion having an aerodynamic upper surface, and a pair of spaced apart laterally positioned portions separated by the medial portion. Lower extremities of the laterally positioned portions extend downwardly below the medial portion to restrain air flow between them as it moves toward the rear of the body. Forward extremities of the laterally positioned portions extend forward of the medial portion to, again, restrain air flow from moving laterally. Power plants are mounted within the medial portion and support aircraft type propellers positioned forward of the medial portion of the body. The propellers are mechanized for moving over an arcuate vertical range, such that their force vectors are directable between the horizontal and approximately 45 degrees above the horizontal.

Abstract: A member for mounting a portable power tool to a vehicle, the mounting member comprising a bracket mounted to the vehicle, a collar member integral with the bracket adapted to engage a portion of said tool and position it at an angle to the longitudinal axis of the vehicle, and a member for removably holding the power tool in position on the bracket. When mounted, the power tool engages a rotatable shaft, the shaft in turn being coupled to the driven wheel of the vehicle through a gearing system. The rotational speed of the shaft, and thus the speed of the vehicle, is controlled by the vehicle driver using a remotely mounted hand control. The vehicle has a free wheel assembly, enabling the vehicle to move even when power is not applied to the power tool.

Abstract: A system for the proportional propulsion assistance by a DC motor propulsion secured to a wheel of a bicycle propelled by a user person who provides an effort. The system has a strain gauge for the detection and measurement of a flexion of a stationary shaft of a rear wheel of the bicycle. The gauge is disposed on a vertical face formed on the shaft. An amplifier amplifies a measurement signal coming from the gauge. A filter is connected at the input of the amplifier. An analog to digital converter is connected at the output of the amplifier. A digital processing circuit digitizes the signal at the output of the amplifier to compensate for any deviation of the signal to calculate, in real time, the effort provided by the user person on the gears secured to the rotor housing of the DC motor secured to the fixed shaft and to control the assistance effort provided by the DC motor of the rear wheel of the bicycle to give a progressive assistance to the user person.

Abstract: A three-wheel vehicle has two forward steered wheels and one rear powered wheel operatively connected to an engine disposed on a frame assembly. A straddle-type seat is disposed between the forward and rear wheels. A rear swing arm is pivotally connected at a first end to the frame at a pivot point and rotatably supports the rear wheel at a second end. A concentric sprocket assembly having first and second sprockets is attached to the swing arm at the pivot point. A transmission member operatively connects an output shaft of the engine and the first sprocket and a second endless flexible transmission member is operatively connnected between the rear wheel and the second sprocket. An eccentric endless flexible transmission member tension adjustment mechanism is attached to the swing arm to move the concentric assembly sprocket relative to a longitudinal axis of the swing arm.

Abstract: An electric scooter includes a scooter frame having a rear cover inside which a fuel cell stack is mounted in an inclined manner and a center cover connected to the rear cover by a footstep section. A front cover is mounted to a front side of the scooter frame and forms an interior space with the center cover. A hydrogen canister holder is mounted in the interior space for retaining a number of hydrogen storage canisters in an inclined manner for supply of hydrogen to the fuel cell stack. The canisters are arranged in pair on opposite sides of a centerline of the scooter frame. A heat dissipation system including a coolant container, a heat exchanger, and a pump is further provided in the interior space to maintain the hydrogen storage canisters at a proper operation temperature.

Abstract: The invention provides vehicle window-shattering (or dicing) systems and apparatuses that enable a vehicle occupant to escape a vehicle in the event of an emergency, particularly when a door or other means of escape is inoperable or undesirable. One embodiment of the invention is a system for dicing vehicle glass that provides a user interface, a propulsion system, and a vehicle glass-dicing tip whereby the propulsion system enables the tip to impact a vehicle window with a force sufficient to dice or shatter the vehicle window.

Abstract: The invention provides vehicle window-shattering systems and apparatuses. One embodiment of the apparatus includes a base having an opening large enough to accommodate a seat belt, and a tip coupled to the base.

Abstract: To enable restart of an engine by detecting that a vehicle is restored to the upright position after overturning in an early state. An acceleration sensor having a detection shaft laid laterally of a vehicle body is integrated into an ECU and mounted on the vehicle body. Outputs of the acceleration sensor are weighted and averaged, and when an average value exceeds an overturn threshold repeatedly, an overturn determination unit determines that the vehicle is overturned. On the other hand, when outputs of the acceleration sensor are determined to be below a restoration threshold, and the determination is repeatedly made, it is determined that the vehicle is restored from the overturned state. The engine is stopped when determination of overturn is made, while restart of the engine is enabled when determination of restoration is made. Especially, the reference value of determination is set so that determination of restoration is made at an early stage.

Abstract: A vehicle has two acceleration sensors, which are provided forward and rearward respectively from the rear end of a driver seat in the vehicle. The acceleration sensors output signals, which are the basis for sensing a signal related to rotation of the vehicle. The sensed signal is the basis for determining whether the vehicle has a lateral collision.

Abstract: An installation for hitching at least one personal transporter in a fixed position relative either to an immobile fixture or another conveyance. The installation has a clasp for coupling a personal transporter in such a manner as to immobilize the transporter. The installation may also have a powering junction for supplying electrical power to the personal transporter, a data connection for transferring information between the installation and the personal transporter, and a heater for heating the personal transporter. Straps may be provided to allow the transporter to be loaded onto a conveyance by wrapping the straps around the driven wheels of the transporter.

Abstract: A steering wheel mounted on a forklift 1 is provided with a steering wheel knob 17 which can be operated with one hand holding it. The steering wheel knob 17 has an approximately egg-like shape with switches 46, 47 provided on its end face. Incorporated in the steering wheel knob 17 are a transmission circuit 49, which radio-transmits a signal when the switches 46, 47 are operated, and a battery 51. The signal transmitted from the steering wheel knob 17 is received by a reception section 68 on a vehicle body 2 and a controller 48 executes predetermined control based on that signal.

Abstract: An electric power steering apparatus comprises an electric motor having a motor housing, a ball screw mechanism connected to the electric motor through power transmission means and used for driving a rack shaft, and a steering gear case encasing the rack shaft and the ball screw mechanism. The electric motor is supported by at least two supporting portions with respect to the steering gear case, and is supported by at lest one of the two supporting portions through an elastic member.

Abstract: A ball screw mechanism comprises a screw shaft, a nut and balls. The nut has a cylindrical portion in the axial middle on the outer peripheral surface thereof that becomes a fitting surface for fitting in a sleeve, and small diameter step portions in the opposite axial sides on the outer peripheral surface thereof that become non-fitting surfaces not fitting in the sleeve. A portion of a wheel steering shaft is provided with the screw shaft, and a plurality of balls are disposed in a rolling way defined between a thread groove formed in the outer periphery of the screw shaft and a thread groove formed in the inner periphery of the nut.

Abstract: An electric power steering apparatus comprises an electric motor having a motor housing, a ball screw mechanism connected to the electric motor through power transmission means and used for driving a rack shaft, and a steering gear case encasing the rack shaft and the ball screw mechanism. The electric motor is supported by at least two supporting portions with respect to the steering gear case, and is supported by at lest one of the two supporting portions through an elastic member.

Abstract: A steering assembly for a vehicle, including an input shaft connectable to a steering input system, an output shaft connectable to a steering output system, a torsion device connecting the input shaft and the output shaft and allowing relative rotation movement between the input shaft and the output shaft based upon a torque applied to the input shaft or the output shaft, a first sensor of sensing relative rotational movement of the input shaft and the vehicle, and a second sensor for sensing relative rotational movement of the output shaft and the vehicle.

Abstract: A speaker enclosure (10) comprising a speaker box (12) having an opening (27) and adapted for mounting within a wall (20) upon a wall stud (22); a compressible gasket (14) affixed about the box opening (27); a faceplate (16); and a plurality of independently adjustable coupling mechanisms (18) for coupling the faceplate (16) with the box (12). The protruding, uncompressed gasket (14) is compressed by the faceplate (16) and the coupling mechanisms (18), which may be independently adjusted to provide an optimum and substantially uniform degree of separation between faceplate (16) and wall (20), thereby reducing distortion, vibration, and damage due to undesirable contact therebetween. A spring (160) is provided to prevent over-compression of the gasket (14) due to heavy or low frequency speakers, thereby facilitating maintaining the uniform degree of separation; and a spacer (162) is provided to maintain the spring (160) in its operating position.

Abstract: The exhaust sound and emission control system is a system for reducing sound and noxious emissions from an automotive exhaust. The system may have an exhaust resonator having one or more catalytic converter elements in combination therewith in a single device. Alternatively, the system may have multiple angularly disposed chambers therein, with a series of V-shaped baffles or guides in one of the chambers, thereby combining resonator and muffler functions in a single device. In another alternative, the system has a series of longitudinal tubes therein, in combination with a series of V-shaped guides or vanes, combining catalytic converter, muffler, and resonator functions in a single device. The various elements of the different embodiments, e.g. catalytic converter element(s), double wall shell, perforated tubes and multiple flow paths, interconnecting crossover tubes, etc., may be combined with one another as practicable.

Abstract: A sound absorbing material having a homogenous mixture of an organic man-made fiber, an inorganic man-made fiber, a co-binder, and a cellulose material wherein the organic man-made fiber is polyester, the inorganic man-made fiber is fiberglass, and the co-binder is a thermo-setting resin. The cellulose material may include Kaolin clay and/or boric acid.

Abstract: A supporting bracket assembly for a horizontal lifeline cable (4) comprises a base plate (14), bracket means (24) and holding means (28) for the cable. The base plate (14) is provided for securing to a structure (6). The bracket means (24) is secured to the base plate and adapted for frictionally restrained pivotability with respect to the base plate and the holding means (28) for the cable (4) is secured to the bracket means (24). In this way, dynamic loading of the cable (4) results in pivoting of the bracket means (24), against frictional restraint, from a first position (36) into a second position (38).

Abstract: Platform assemblies may be built up using a substantial number of inverted U-shaped vertical supports with platform hold down members that hold the platforms in place, thus avoiding slippage or pilferage. The hold down members form a unitary structure with the supports and platform assemblies to hold the platforms securely in place. The unitary structure of the scaffolding assembly with hold down members acts as a deterrent against pilferage of the platforms because the unitary structure does not allow the planks to be removed unless the platform assembly is substantially disassembled. It also reduces the steps required to assemble a secure platform assembly with hold down members thus saving time while still preventing slippage and pilferage. The hold down members may have holes at one end, and these holes have a diameter slightly greater than the outer diameter (OD) of the guide pipes at the junctions between vertically extending pipes.

Abstract: The invention relates to a vertical scaffolding element consisting of a tubular portion provided with a number n of radially projecting sockets, distributed peripherally in a star arrangement, designed for the attachment of one end of a horizontal crosspiece of the scaffolding; the sockets are defined by a metal strip folded in order to form a star-shaped part closed on itself having protuberances forming the said sockets alternating with re-entrant regions bearing against the tubular portion, the upper and lower edges of the reentrant regions in contact with the tubular portion being welded thereto by continuous or discontinuous annular weld beads.

Abstract: A skirt for use on an applicator bar, wherein the applicator bar includes a body and a flow passageway having an exit end defined in the body, and wherein a second section of the skirt defining a lip is adapted to coact with the body so that the second section is positioned adjacent the exit end of the body.

Abstract: An oil-hydraulic vehicle comprising (i) at least one oil-hydraulic pump 10 driven by an engine E, an input shaft of said oil-hydraulic pump being directly coupled with a crankshaft of the engine, (ii) at least one oil-hydraulic motor 30 to drive at least one wheel 31 in both forward and backward directions, (iii) an oil-hydraulic circuit 50 to connect said oil-hydraulic pump 10 and said oil-hydraulic motor 30, and (iv) at least one flow control valve 60 provided between said at least one oil-hydraulic pump 10 and said at least one oil-hydraulic motor 30.