Abstract: The present disclosure relates to an electric machine, a vehicle comprising such an electric machine and a manufacturing method for such an electric machine. The electric machine comprises a stator unit, a rotor unit, a housing, and a heat exchanging unit. The stator unit and the rotor unit are arranged inside the housing and the housing comprises an inlet port configured to provide a medium inside the housing and an outlet port configured to release the medium out of the housing. The heat exchanging unit is coupled with each of the inlet port and the outlet port and comprises a plurality of channels arranged on an outer surface of the housing. The plurality of channels being configured to transfer heat between the medium and the environment.

Abstract: A slasher saw system connectable to a source of hydraulic power which requires hydraulic lines for power and operation. First, a pressure/power hydraulic line is actuated to turn the saw on and bring the saw down to cut through a stack of timber. Second, the hydraulic pressure/power to bring the saw down is actually provided via back-pressure from a return line returning hydraulic fluid to the source of hydraulic power from the saw. Third, a separate line is used to power the hydraulic cylinder used to raise the saw arm again. Fourth, a separate line including a one-way fluid valve allowing hydraulic fluid flow only from the hydraulic fluid output of the saw blade motor to the hydraulic fluid input for the saw blade motor.

Abstract: A device for conveying thick matter including a thick matter pump; a feed line which leads away from the pump; a boom which receives the feed line and which includes at least one boom arm and which is arranged on a swivel bogie, wherein the swivel bogie is rotatable for angular orientation of the boom through a drive, in particular a hydraulic motor with a transmission arranged thereon, and a measuring device which includes rotation angle sensors for measuring the rotation angle of the swivel bogie, wherein the rotation angle of the swivel bogie is measured through direct measurement of a rotation angle of the drive or of the transmission arranged between the motor and swivel bogie.

Abstract: Apparatus for manipulating a longitudinally extensive member comprises a main body portion, ground contacting assemblies on which said main body portion is mounted, said ground contact assemblies being operable to convey the apparatus over a ground surface, a trench cutting device, and a mounting arm depending directly or indirectly from said main body portion and having a proximal end arranged proximate said main body portion and a distal end arranged distal from said main body portion, said distal end being operatively laterally movable with respect to the main body portion between a first limit position towards a first side of the apparatus and a second limit position towards an opposite second side of the apparatus. The mounting arm is provided with a lifting device configured to lift, and/or support assembly configured to support, said longitudinally extensive member, proximate said distal end thereof.

Abstract: An apparatus, method, and system are disclosed for cutting materials such as concrete. The apparatus includes a mounting assembly, and a pair of blades that are mounted at an end of the mounting assembly. Various types of driving assemblies can be provided to supply the force necessary to rotate the two blades. The distance between the blades can also be varied in order to adjust the width of the cut.

Abstract: A pneumatic impulse wrench for tightening screw joints includes a housing with a pressure air inlet passage, an exhaust air outlet passage, a rotation motor, a hydraulic impulse generator, and is connected to a stationary programmable control unit. The impulse wrench also includes a torque indicating mechanism connected to the control unit for feeding back electric signals responsive to the output torque of the wrench, an electromagnetically activated inlet valve arranged in the air inlet passage, and an electromagnetically activated exhaust valve which controls the exhaust air flow from the motor. The exhaust valve is a proportional valve activated by a linearly operated electromagnetic actuator and arranged to continuously adapt the exhaust air flow and, hence, the motor power to the characteristics of the actual screw joint being tightened in response to feed back signals from the torque indicating mechanism and in accordance with a programmed tightening strategy.

Abstract: An arrangement and a method for controlling at least one drill parameter when drilling in rock with a rock drill, comprising an impulse-generating device arranged to induce shock waves in a tool acting against the rock with a percussive force generated via a shock wave-generating pressure. The arrangement and method comprises a control system for determining a first parameter value representing the damping pressure, determining a second parameter value representing the rotation pressure of a drill bit, determining a deviation between the second parameter value and a rotation pressure reference value, determining a parameter reference value depending on the deviation, and regulating the percussion pressure based on a function of the deviation and the parameter reference value.

Abstract: A method of modifying a hand-held tool which having a stationary handle actuated by a movable handle connected to a movable tool jaw by a connection linkage, the method including removing the moving handle and the stationary handle. A pneumatic actuator with a piston rod is added. The connection linkage is modified to extend between the piston rod and the movable tool jaw. A trigger is added between the pneumatic actuator and a source of pressurized gas.

Abstract: A hydraulic control system includes a first motor, a second motor, a pump operatively associated with the first motor, a first coupling valve operatively associated with the second motor, first parallel valves operatively associated with the second motor, and a first switching valve operatively associated with the first coupling valve and the first parallel valves. The first switching valve is configured to switch the first coupling valve between a first coupling state and a second coupling state opposite the first coupling state and to switch the first parallel valves between a first parallel state and a second parallel state opposite the first parallel state. While the first parallel valves are in the first parallel state a portion of the output of the first motor drives the second motor while the first parallel valves are in the second parallel state, the output of the pump drives the second motor.

Abstract: In a hydraulic system for mining equipment and a method of adjusting the power of a rock drill machine, at least one mining actuator used for detaching rock is connected to a dedicated separate hydraulic circuit having a special hydraulic pump. The power of the mining actuator is adjusted by changing the hydraulic power generated by the separate hydraulic circuit of the hydraulic pump.

Abstract: A method, arrangement and valve for controlling rock drilling. In the method, a pressure difference acting across a rotation motor is used to regulate a separate feed regulating valve, which, on the basis of this, regulates control pressures of a feed control valve. The arrangement comprises a separate feed regulating valve, which, under the influence of the pressure difference acting across the rotation motor, regulates control pressures of a feed control valve. The valve comprises a separate retarding element, which slows down the returning of a spool of the valve to the normal position, if the spool has moved away from its normal position under the influence of the pressure difference acting across the rotation motor.

Abstract: The invention relates to a rock drilling arrangement and a method and program for controlling rock drilling on the basis of specific energy consumption. The specific energy of drilling is the quantity of energy used per a unit of length of the drilled hole. Not only the used impact energy, but also the energy used by at least one other sub-process is taken into account when determining the specific energy. Rotation energy is typically included, but feeding energy and flushing energy can also be considered. Drilling variables are adjusted so that the specific energy is of a predetermined size.

Abstract: A device for supplying hydraulic power to a rotary apparatus for percussive drilling (2) whereof the tool (3) is driven in one direction or another and subjected to the action of an impact device (6) acting independently of the rotation, of a hydraulic device (9) with forward movement enabling the tool to generate a pressure force on the ground, and optionally of a suction device (14) for the drilling dusts, driven by a hydraulic motor, the various hydraulic actuating elements being driven from a hydraulic liquid source under pressure through a hydraulic flow divider (16), a set of distributors (17, 18, 19, 20) and an assembly of branch pipes outside the apparatus, such as hose pipes. The device includes a branch pipe external to the apparatus (24) for communicating the return branch pipe (22) of the hydraulic device (4) driving the tool in rotation and the supply line (23) of the impact device (6), to add to the supply rate of the impact device the return flow rate of the rotation driving device.

Abstract: The invention comprises a staple gun with highly compact accessory apparatus for attaching a planar tab or label to a fixing surface. The accessory has a housing and a positioning and indexing assembly associated with the housing which is operable to feed and hold a tab or label between the staple gun head and fixing surface, thereby allowing single-handed fixing of a label or tab to a fixing surface. The apparatus can include a roller assembly, staple gun and accessory apparatus or have all components integrated into the construction of a staple gun apparatus. Preferably, the apparatus is mated with a tab or label holding magazine. Some exemplary embodiments of the invention are suitable for securing protective covering to lumber product and may be configured for rectangular polyolefin tabs measuring approximately 0.035 inch thick and 1.0 inches by 2.0 inches.

Abstract: A lockout mechanism for a fastener driving tool having a magazine for storing and sequentially urging fasteners toward a nosepiece through which a driver blade impacts and drives the fasteners into a workpiece, the lockout mechanism is configured for preventing the firing of the fastener driving tool when the magazine is empty or nearly empty of fasteners. A fastener track is defined in the magazine for the passage of the fasteners toward the nosepiece. A biased follower urges the fasteners in the fastener track toward the nosepiece. The fastener track has a bypass portion dimensioned for receiving the follower whereby upon reaching the bypass portion, the follower becomes disengaged from the fasteners and moves into engagement with the nosepiece for preventing operation of the tool. The bypass portion is located near a magazine driving end to indicate when the magazine is empty or nearly empty.

Abstract: The rock drill (9) includes a reversible rotary motor (10) and a percussion unit (11) with a percussion valve (17). Rotary unit and Percussion unit (11) are operated via separate valves (39, 46) in a control unit (34). The percussion frequency of the percussion unit (11) is coupled to the rotation rate of the rotary motor (10) in such a way that the percussion unit (11) stops automatically when the rotary motor (10) comes to a standstill. The coupling is achieved by employing a fluid driven assembly without a mechanical clutch between the rotary motor (10) and the percussion valve (17). When disassembling the drill rods a jammed thread can be shaken loose with the percussion unit (11) be manually bypassing the fluid coupling. The same is also possible in case the drill rods becomes jammed in the drill bore. With the described embodiment a simple, space-saving and cost-effective construction is achieved which is versatile in application.

Abstract: Arrangement in a hydraulically operated rock drilling equipment comprising a feed motor (3), a percussion device (2), and a hydraulic pump (1) for feeding hydraulic fluid to the feed motor (3) and the percussion device (2). The arrangement comprises a pressure control valve (17) connected to be controlled on the basis of the control signal of the feed regulation valve (8) when starting the drilling so that when the value of the control signal is below a predetermined switching value, the pressure relief valve (18) is connected to the percussion pressure line (13) of the percussion device (2), and when the control signal exceeds the switching value, the pressure control valve (17) disconnects the pressure relief valve (18) from the percussion pressure line (13) and connects the pressure difference valve (20) in communication with the percussion pressure line (13).

Abstract: A control system for a percussion drill with a hydraulically actuated drill rotation mechanism and drill feed mechanism which includes a control means which operates, in response to the hydraulic pressure in the drill feed mechanism, to start percussion movement of the drill.

Abstract: In forging hammers, according to the present invention, more than one inlet valve is employed and more than one exhaust may be employed. The force of impact for a particular blow is controlled by the number of valves employed and the timing of the opening and closing of those valves relative to one another. By making successive adjustments with different combination of valves, the controls may be calibrated so that the same ram force may be repeated. Knowing the valve settings required to produce differing amounts of force, it is possible to program the settings into the memory of a computer, so that when a particular impact force is selected the appropriate valve timing will be reproduced and the desired force obtained. It is also possible to set up a sequence of blows of differing selected force, setting each blow using the computer memory.

Abstract: A hydraulic circuit (10) is disclosed for use in controlling a horizontal boring machine which requires hydraulic fluid under pressure for rotating a drill bit or backreamer through a rotation circuit and hydraulic fluid under pressure for thrusting the drill bit or backreamer within the bore hole through a thrust circuit. Pressures from both the thrust circuit and control circuit are combined through restrictors in a mixing zone or area (26). The control port of a diversion valve (32) is connected to mixing zone (26). When the combined pressure in the mixing zone exceeds the adjustable spring bias on the diversion valve, the diversion valve will open, diverting fluid from the thrust circuit to a low pressure zone. This will cause a reduction in the pressure in the rotation circuit as well. The reduction of both pressures will reduce the combined pressure in the mixing zone (26), causing the diversion valve to close and the pressures to increase.

Abstract: The invention relates to a method and an arrangement for adjusting the percussion and the feed of a rock drilling apparatus with respect to each other. In the method, the volume flow of pressure fluid to be supplied to a percussion device (7) and a feed motor (8) is adjusted on the basis of the feed pressure of the feed motor (11), a volume flow adjusted pump (1) being controlled so that the ratio of the pressure applied to the persussion device (7) to the pressure of the feed motor (11) is set by control valves (10, 14). In the arrangement, pressure fluid is supplied to the percussion device (7) and the feed motor (11) by means of a volume flow adjusted pump (1). The arrangement further comprises control valves (10, 14) by means of which the volume flow of the pressure fluid fed by the pump (1) is kept such that the ratio of the pressure of the percussion device and that of the feed motor (11) remains substantially constant.

Abstract: A working head for a tree-shaping machine comprises drive means and at least one shaping unit comprising at least one mobile blade and an actuating jack (8, 9) for applying the blade to the surface of a tree. The pressure in the jacks is cancelled during the starting phase of the drive means.

Abstract: A forging hammer employs compressible fluid to drive the ram into impact and a trapped volume of compressible fluid to cause the ram to be retracted from impact position when fluid driving the ram into impact is released. The velocity of impact is adjusted by the timing of the opening of a valve allowing variable amounts of compressible fluid into a cylinder from a compressible fluid supply. Historical data is accumulated on a given forging hammer correlating the peak lifting fluid pressure with ram stroke. Thereafter, it is possible by measuring lifting fluid pressure and obtaining the peak value to determine the stroke by comparing the measured value against compiled pressure vs. stroke data for various residual lifting air pressures. Knowing the dimensions of dies and other structures employed with a forging hammer, it is then possible to calculate the rate of deformation from the forging size of the previous blow and the forging size of the current blow.

Abstract: A forging hammer employs compressible fluid to drive the ram into impact and a trapped volume of compressible fluid to cause the ram to be retracted from impact position when fluid driving the ram into impact is released. The velocity of impact is adjusted by the timing of the opening of a valve allowing variable amounts of compressed fluid into a cylinder from a compressible fluid supply. As the ram is driven into impact, the compressible fluid which causes the ram to be retracted is compressed and increases in pressure. The peak of pressure in this trapped volume of compressible fluid is sensed and compared with a peak value of reference pressure which represents a desired impact energy. If there is an error between the measured peak and the desired peak effect, an incrementing or decrementing signal is provided to correct the valve to adjust the effect of the next blow.

Abstract: A forging hammer employs compressible fluid to drive the ram into impact and a trapped volume of compressible fluid to cause the ram to be retracted from impact position when fluid driving the ram into impact is released. The velocity of impact is adjusted by the timing of the opening of a valve allowing variable amounts of compressible fluid into a cylinder from a compressible fluid supply. Pressure sensing means is provided to sense the pressure of the lifting fluid, calculating means for calculating kinetic energy from the rate of change of lifting air pressure, comparator means for comparing kinetic energy with a standard and a counter for accumulating error. Sensing the rate of change of pressure of the lifting fluid permits calculation of the velocity of the hammer. Kinetic energy at the time of impact is calculated from the velocity and the mass of the ram assembly.

Abstract: In a method of and device for adjusting the feed movement of a drill rod for drilling a rock, the drill rod is rotated by a pressure-medium-operated rotary motor and fed in a drilling direction and in the opposite direction by a pressure-medium-operated feed motor. A pressure change on the pressure side of the rotary motor due to a change in the rotation resistance on the rotary motor acts oppositely on the pressure and outlet sides of the feed motor toward reversing the feed force of the feed motor, i.e. in inverse and direct dependence on the pressure change, respectively. The pressures on the pressure side and the outlet side of the feed motor are, therefore, controlled so that, when the pressure on one side increases because of the pressure change, the pressure on the other side decreases and vice versa.

Abstract: A method and apparatus for controlling the rotational torque of a drill bit powered by a downhole motor. The downhole motor is suspended from a hydraulic ram at the lower end of a string of drill pipe. A torque sensor detects the reactive torque in the downhole motor during drilling. In response to the detected torque level, pressurized drilling fluid from the downhole motor is provided to the hydraulic ram thereby varying the weight applied to the drill bit in order to maintain a constant torque level.

Abstract: Apparatus and method for digging deep trenches having parallel generally vertical walls in solid rock such as limestone. The apparatus includes a transport means for providing support and for moving along a traverse on the earth's surface while cutting a trench along that traverse. The transport carries a boom which may be articulated into the ditch being cut and a pair of rock cutterwheels carried on the end of the boom and assembled so that the outermost cutter teeth are wider than any other part of the boom assembly. The apparatus further includes means for aligning the flat surfaces of the rock cutter wheels parallel to and between the walls of the ditch and for maintaining alignment of the wheels with the trench as the transport moves along the traverse so that repeated cuts may be made to extend the trench to any desired depth.

Abstract: A rock drill having a hydraulic system for controlling striking, rotating and advancing movements of a drilling rod. The advancing or forward feeding conduit for a feed actuator is provided with a relief valve which is responsive to the pressure in the positive rotating conduit for a rotary actuator so that the pressure in the forward feeding conduit is relieved to weaken the advancing force when the load on the rotary actuator is increased. A further relief valve is also provided for relieving the pressure in the striker conduit to weaken the striking force.

Abstract: A hydraulic control system for use with a rock drill is adapted to sense a pressure build-up in the drill's rotation motor and in response thereto, to reverse the direction of feed of the feed motor as well as to supply hydraulic fluid to a shank cylinder on the rock drill. Supplying hydraulic fluid to the shank cylinder assists in freeing the drill from the rock.

Abstract: A rock drill having a hydraulic system for controlling a striking, rotating and advancing movements of a drilling rod. The advancing or forward feeding conduit for a feed actuator is provided with a relief valve which is responsive to the pressure in the positive rotating conduit for a rotary actuator so that the pressure in the forward feeding conduit is relieved to weaken the advancing force when the load on the rotary actuator is increased. A further relief valve is also provided for relieving the pressure in the striker conduit to weaken the striking force. A switching valve is provided between the advancing and retreating conduits for the feed actuator so that the direction of movement of the feed actuator is automatically changed when there is an abrupt decrease in the pressure in the striker conduit.

Abstract: The method and power transmission system of this invention for driving a road planar machine has the cutter unit in a positive mechanical drive with the drive shaft of a machine power unit through a hydraulically actuated clutch mechanism. The wheel traction units for the machine are continuously driven from the power unit by hydraulic motors operated by variable volume displacement pumps. A control system for retaining the power unit at a set rotational speed required for a predetermined cutting or planing load is responsive to a drop in the set rotational speed, resulting from the cutting unit encountering an overload, to actuate the variable displacement pumps to decrease the forward speed of the machine without appreciably reducing the rotational inertia force of the cutting unit. If the cutting unit overload is of a short duration or momentary the set rotational speed of the power unit is resumed.

Abstract: A torque control for a fluid operated motor includes a first gear to be driven through operation of the motor and a second gear in driving engagement with said motor and maintained in a generally stationary position during normal operation thereof. The torque control further includes a drive mechanism connected to the first gear and to a load to be rotationally driven through operation of the motor. A valve is provided in the fluid supply to the motor to open and close the supply of fluid thereto. Disconnect means is operatively connected to the second gear and the valve to maintain said valve in an open position to permit supply of fluid to said motor when the second gear is stationary. The second gear rotates when the torque required from the motor to rotate the load exceeds a predetermined magnitude to move the disconnect means relative to the valve to close the valve to terminate the supply of fluid to the motor.

Abstract: An apparatus operable on a wireline logging cable for drilling a hole in the sidewall of a drill hole which comprises a hydraulically operated backup shoe for wedging the apparatus at a selected location in the drill hole, a hydraulic motor with a drilling bit connected thereto for rotation by the hydraulic motor and hydraulic means connected to the hydraulic motor for moving the bit into drilling engagement with the sidewall of the drill hole. In the improvement of this invention, the hydraulic means for moving the bit into drilling engagement comprises a new flow restrictor valve. This flow restrictor valve has an orifice and a slender pointed rod for restricting the flow of fluid through the orifice. Opposing spring means and control fluid means engage the rod for controlling its movement toward and away from the orifice.

Abstract: A needle valve placed in series with the hydraulic drill feed motor, and responsive to fluid flow in the hydrualic system subject to the operation of a pressure relief valve therein, causes the thrust to increase and the feed rate to decrease as the drill enters a difficult drilling material, a proportional flow divider interposed between the pressurized hydraulic fluid source and the hydraulic drill rotation motor and the hydraulic feed motor splits the flow and maintains a fixed proportion between the flows to the two motors to cause the rotational motor to slow down as the feed motor slows down. A pressure compensated flow control valve bypassing the proportional flow divider to the drill rotation motor insures a fixed amount of fluid flow to the rotational motor regardless of the difficulty of material being drilled to maintain a minimal rotational speed of the drill rotation motor.

Abstract: A drilling apparatus includes a drilling rod, a feed motor for advancing and retreating the rod in relation to an object to be drilled, and a control system for controlling the movement of the rod. The control system includes a pulse generator for producing one long duration pulse upon completion of each rotation of the drilling rod, an oscillator for producing high frequency pulses, a counter for counting the number of high frequency pulses during the long duration pulse, and a control circuit for controlling the feed motor in response to the counted number of pulses, the control system operating so that the counted number of high frequency pulses equals a predetermined number during the period of the long duration pulse.The control system is arranged to increase the advancing force of the drilling rod when its rotational speed increases (i.e.

Abstract: A control system for a hydraulic percussion rock drill and feed mechanism including a single constant power hydraulic pump for supplying pressure fluid to operate the feed mechanism, drill stem rotation motor, and the percussion hammer. The drill feed, rotation and percussion functions are controlled by individual manually actuated pressure compensated valves. Fluid pressure to the feed mechanism is controllable at one of two selectable pressures and is automatically reduced if fluid pressure to the drill stem rotation motor exceeds a predetermined limit. The drill percussion blow intensity and frequency is controlled by a mechanism responsive to a fluid pressure signal which is automatically operated to provide for a high blow frequency and low blow intensity operating mode when the drill is retracted away from the workface. The constant power hydraulic pump is provided with a control which will adjust the pump output to a partial displacement setting when the drill is being retracted away from the workface.

Abstract: An apparatus employed in the searching of the optimized rate of penetration of a drill into a given medium based upon the two drilling parameters of thrust and speed of revolution. Preset base values of both parameters are input into the drilling control mechanism at the start of drilling. Thereafter, based upon readings from an automatic penetration rate calculator, the apparatus effects automatic incremental changes to one of the parameters, the other being held constant, until a maximized rate of penetration is established. Subsequently, the other parameter, previously held constant, is changed until a new maximized penetration rate is found. This optimized penetration rate searching is continuously and automatically effected until the drilling process is completed. The apparatus additionally provides for the allowance of a wait period between successive incremental changes for accommodating response times of the system as well as instabilities which may occur as the result of nonlinear process dynamics.

Abstract: This disclosure relates to a machine for clearing bulk material from a bin table by moving therealong a movable support carrying a pivotally mounted rotatable clearing wheel including a first drive mechanism for moving the movable support and a second drive mechanism for rotating the clearing wheel and a control mechanism responsive to operational conditions of the second drive mechanism for controlling the operation of the first drive mechanism whereby the rotational speed of the clearing wheel may be increased or decreased as might be the speed of the movable support in dependence upon the resistance of the bulk material being offered to the clearing wheel during the rotation of the latter.

Abstract: A hydraulic drilling machine for cutting into rock formations and the like. The machine has a rotating drill rod with a bit at one end and a rotary hydraulic drive motor at the other end. The drill rod is supported on a carriage adapted for linear travel to advance the rotating bit into the rock formation. The carriage is extended and retracted by means of a hydraulic feed motor. The rotary hydraulic motor and the hydraulic feed motor are connected in series in the hydraulic operating system so that when rotation resistance increases accompanied by a greater pressure drop across the rotary hydraulic motor, there is a consequent decrease in the force exerted by the hydraulic feed motor in order to avoid jamming of the drill bit.

Abstract: A hydraulic drill, more particularly a rock drill, having a self-adaptive servo control system comprising three separate but interdependent hydraulic circuits, one for operating and controlling the drill rotation motor, one for controlling and operating the drill impact unit and a third for operating and controlling the drill feed motor.

Abstract: A hydraulic rock drill having a hydraulic drill drive motor, a hydraulic feed motor, and a hydraulic impact unit and associated pumps for supplying hydraulic fluid under pressure and provided with an automatic control system including a valve controlling the flow to the impact unit under the dependence of the pressure in the rotation motor circuit such as to reduce the power of the impact unit when the pressure in the drive motor circuit exceeds a permissible pressure and vice versa. Additionally, the hydraulic system preferably includes an additional flow control valve such as to decrease the feed power when the impact power increases.

Abstract: A hydraulically controlled and driven dredge, in which the pumps for delivering the driving fluid for the bucket wheel drive are equipped with output controls for controlling the fluid delivery in conformity with the encountered digging resistance and that a control conduit branched off from a pressure conduit leading to a hydraulic motor for driving the bucket wheel is connected to an output limiting valve located in a control circuit which includes an adjusting device connected through conduits to a manually operable control for varying the delivery and the delivery direction of the pump for actuating the hydraulic motor for pivoting the upper structure of the dredge. The fluid delivery of the pumps to the hydraulic motor employed for driving the track laying mechanism being conveyed to the hydraulic motor for driving the bucket wheel when the track laying mechanism is not to be operated.

Abstract: A fastener driving tool includes a housing assembly with a nosepiece assembly defining a drive track. A driving mechanism is housed within the housing assembly to drive a fastener through the drive track and into a workpiece in response to a trigger. The tool includes a safety trip assembly which includes a trigger enabling portion and a workpiece engaging portion and is movable between an extended disabling position and a retracted enabling position. The safety trip assembly is biased toward the extended position and is moved toward the retracted position by engagement between the workpiece and the workpiece engaging member. The workpiece engaging portion is movable to permit adjustment of a length of the safety trip assembly. The safety trip assembly includes a coupling mechanism including a fixed locking structure formed on an exterior portion of the workpiece engaging portion and a manually operable locking mechanism.

Abstract: A hydraulic circuit (10) is disclosed for use in controlling a horizontal boring machine which requires hydraulic fluid under pressure for rotating a drill bit or backreamer through a rotation circuit and hydraulic fluid under pressure for thrusting the drill bit or backreamer within the bore hole through a thrust circuit. Pressures from both the thrust circuit and control circuit are combined through restrictors in a mixing zone or area (26). The control port of a diversion valve (32) is connected to mixing zone (26). When the combined pressure in the mixing zone exceeds the adjustable spring bias on the diversion valve, the diversion valve will open, diverting fluid from the thrust circuit to a low pressure zone. This will cause a reduction in the pressure in the rotation circuit as well. The reduction of both pressures will reduce the combined pressure in the mixing zone (26), causing the diversion valve to close and the pressures to increase.