Abstract: A torque delivering power tool includes a power line driven by a motor. The power line includes an input part with an input shaft, an output part with an output shaft, and at least one gear. The input shaft is drivingly connected to the output shaft via the gear. A motor shaft is drivingly connected to the input shaft via a reduction gearing. A torque meter monitors a torque acting in at least one point along the power line, an angle meter monitors an angular rotation in the power line, and an index meter monitors absolute angular positions of the input shaft or the output shaft. A control unit receives information from the angle meter, torque meter and index meter, and controls a torque output of the motor according to a mapping function corresponding to an angular index position dependent torque transmission over the power line.

Abstract: A foldable parabolic solar collector includes a first panel having a semi-parabolic reflective inner surface, a central tube to which the first panel is fixed, and a second panel having a semi-parabolic reflective inner surface. The second panel is pivotably mounted to the central tube with the reflective inner surface of the second panel facing the reflective inner surface of the first panel. A receiver tube carries a heat transfer fluid. A tracking motor rotates the central tube. A torque sensor lies in between the tracking motor and the central tube and is configured to measure torque between the tracking motor and the central tube. A servomotor pivots the second panel about the central tube between an open position and a closed position when it is determined by a controller that the torque between the tracking motor and the central tube exceeds a predetermined torque threshold.

Abstract: A method of drilling a borehole in an earth formation includes deploying a drilling assembly including a drill bit and a drill string, and performing a drilling operation according to one or more operational parameters to advance the drilling assembly through the formation, wherein performing the drilling operation includes rotating the drill bit and at least a portion of the drill string. The method also includes, during the advancing, monitoring a downhole condition, determining whether the downhole condition indicates at least one of a cuttings accumulation in the borehole and wear of a downhole component, and in response to the downhole condition indicating the cuttings accumulation or the wear, adjusting at least one operational parameter to induce or adjust an oscillating motion in the drill string, the oscillating motion causing at least one of a reduction in the cuttings accumulation and a reduction of wear of the downhole component.

Abstract: A system to optimize a drilling parameter of a drill string includes a drill string control subsystem. The system includes an optimization controller to coordinate operations of the drill string control subsystem during a drilling process at least in part by: determining a first optimized rate of penetration based on a drilling parameter model and a first drilling parameter estimate; providing a first set of commands to the drill string control subsystem based on the first optimized rate of penetration; determining a second drilling parameter estimate during the drilling process based, at least in part, on the drilling parameter model and feedback corresponding to the drill string control subsystem; determining a second optimized rate of penetration during the drilling process based on the second drilling parameter estimate; and providing a second set of commands to the drill string control subsystem based on the second optimized rate of penetration.

Abstract: A fastener driving apparatus includes a vacuum piston and a drive piston, which vacuum piston, when moved (by way of a motor and linear motion converter), draws a vacuum against the drive piston, which drive piston may be held in place by retention means. An anvil is coupled to the drive piston. The retention means is released electrically or mechanically at or near the point of maximum vacuum volume. This drive piston and anvil assembly is then driven by atmospheric pressure and may strike a fastener to drive it into a substrate. At least one position sensor may be used. Once the fastener is driven, the apparatus may reset to an initial position. At least one parasitic loss seal may be provided to reduce drag force on the drive piston, and a timed dwell may be provided for the vacuum piston for operation.

Abstract: The compensating/performance regulation system includes a power skin brush having a handle, an oscillating brushhead workpiece and a drive system, wherein the brushhead workpiece has an RFID tag. An RFID reader is provided in the handle and is responsive to the RFID tag moving past the reader to produce an indication of use of the brushhead. A microprocessor calculates a value of actual use from the RFID information and uses stored information to determine the decline in performance from the calculated use. A compensating change in drive frequency or duty cycle of the drive signal is then determined by the microprocessor from stored information and transmitted to the drive system to maintain performance of the appliance.

Abstract: A fastener driving apparatus includes a vacuum piston and a drive piston, which vacuum piston, when moved (by way of a motor and linear motion converter), draws a vacuum against the drive piston, which drive piston may be held in place by retention means. An anvil is coupled to the drive piston. The retention means is released electrically or mechanically at or near the point of maximum vacuum volume. This drive piston and anvil assembly is then driven by atmospheric pressure and may strike as fastener to drive it into a substrate. At least one position sensor may be used. Once the fastener is driven, the apparatus may reset to an initial position. At least one valve may be included to dump the energy stored in the vacuum in the case of a jam condition, thus providing good safety profile.

Abstract: A method of operating a rotary tool driven by a brushless motor including a DC brushless motor for rotationally driving a rotary bit, a torque setting clutch mechanism, a drive switch for drive-controlling a drive control circuit of the brushless motor, and a control means to rotationally drive the brushless motor by an operation of the drive switch and wherein the method includes a first step for stop-controlling of the drive control circuit, a second step for rotating forward or in reverse the brushless motor through the control and a third step for control-operating a semiconductor of an inverter circuit provided in the drive control circuit to short-circuit the magnetizing windings of the brushless motor, thus braking the rotor of the brushless motor and stopping the brushless motor.

Abstract: A power tool includes a brushless DC motor housed inside a tool housing, an input unit, and a control unit. The motor includes a rotor, a stator, and at least one sensor positioned to sense a state of the rotational position of the rotor inside the stator. A control unit controls commutation of the motor through a series of power switches coupled to the power supply. The control unit receives a current sensor state from the sensor and a user-selected speed from the input unit and determines whether the motor has reversed direction using the user-selected speed and the current sensor state. The control unit disables commutation of the motor if the motor has reversed direction until a proper current sensor state is received from the sensor.

Abstract: A portable power tool having a housing with a rotation motor for powering a working implement, wherein sensors are provided to indicate the motor speed and the power supply, and a programmable evaluation unit is arranged to compare indicated speed and pressure values with stored limit values, and to accumulate the total operation time of the power tool and compare that with preset time limits for tool service intervals, and an optical information unit is provided on the housing to indicate whether those stored limit values have been reached.

Abstract: An electric assembly device for tightening of fastener includes a housing and a rotation. motor which is drivingly connected to an output shaft. The output shaft has a forward portion extending out of the housing, and is adapted to carry a coupling device for releasable coupling with a fastener during tightening, which is to be performed along a first rotation axis. The device is adapted to determine an angular displacement of the housing with respect to the first rotation axis during tightening of the fastener, and to control the rotation speed of the motor during tightening based on the determined angular displacement of the housing.

Abstract: A pneumatically striking hand-held power tool is controlled by the following steps. An acceleration (a) along a striking axis (8) of the hand-held power tool (1) is detected. A driving power is reduced if the detected acceleration (a) is greater than a threshold value (A), the threshold value (A) being selected to be greater than maximum acceleration values (a1, a2) that occur on a workpiece during the striking operation of the hand-held power tool (1).

Abstract: Pneumatic drifters containing a drifter cylinder with removable feet and associated methods for using the pneumatic drifters are described. The removable feet are connected to feet pad of a drifter cylinder with multiple fasteners. The mating surfaces of the feet and the feet pad are provided with complimentary features that limit the shearing forces on the fasteners during operation of the drifter rock drill. The removable feet can be replaced quickly and easily without have to replace the entire drifter cylinder, thereby saving time and reducing costs. Other embodiments are also described.

Abstract: An electric power tool includes a motor, a reduction mechanism, a driving unit, a bearing unit, a housing, a speed changing unit, a power switch, and an operation detecting unit which detects a reduction ratio changing operation performed by the speed changing unit to control electric power supplied to the motor. The reduction mechanism transfers the rotating power of the motor, and the driving unit transfers the rotating power of the reduction mechanism to a tip end tool. The bearing unit rotatably supports the driving unit, and the housing accommodates the motor, the reduction mechanism, the driving unit and the bearing unit. The speed changing unit changes a reduction ratio of the reduction mechanism, a power switch for turning on and off a power source of the motor.

Abstract: A rotary angle tool is provided for driving a fastener while controlling the rotational speed of the chuck by varying the pressure or force of the tool against the fastener. The tool includes an angled chuck assembly that is drivable by a motor, an output shaft of the chuck assembly having a rotational axis that is non-parallel to the rotational axis of the motor drive shaft. A sensor is responsive to the proximity of or movement of a detectable element at the chuck output shaft. The sensor generates a signal for controlling the output of the motor in response to detection of the proximity or movement of the detectable element. Moving the chuck output shaft by urging the rotary tool against a fastener varies the proximity of the detectable element relative to the sensor and the sensor output or control proportionally varies the power supplied to the motor.

Abstract: A control system is provided for use in a power tool. The control system includes: a rotational rate sensor having a resonating mass and a controller electrically connected to the rotational rate sensor. The rotational rate sensor detects lateral displacement of the resonating mass and generates a signal indicative of the detected lateral displacement, such that the lateral displacement is directly proportional to a rotational speed at which the power tool rotates about an axis of the rotary shaft. Based on the generated signal, the controller initiates a protective operation to avoid further undesirable rotation of the power tool. The controller may opt to reduce the torque applied to shaft to a non-zero value that enables the operator to regain control of the tool.

Abstract: Pneumatic drifters containing a drifter cylinder with removable feet and associated methods for using the pneumatic drifters are described. The removable feet are connected to feet pad of a drifter cylinder with multiple fasteners. The mating surfaces of the feet and the feet pad are provided with complimentary features that limit the shearing forces on the fasteners during operation of the drifter rock drill. The removable feet can be replaced quickly and easily without have to replace the entire drifter cylinder, thereby saving time and reducing costs. Other embodiments are also described.

Abstract: A lifting device such as a mobile crane having a main body and a boom, such as a lattice boom, for supporting a pile lead for, e.g., pile driving or continuous flight auger drilling, and a method of using same. A hydraulically operated mechanical spotter arm may be attached between the device body and the pile lead. Electronic position sensors on the spotter arm may be used to measure angular relationships between the pile lead and the spotter arm. Position sensors on a boom box on the boom may also be used. When the pile lead is swung, information from the sensors may be used by an electronic control system to automatically maintain the pile lead in a desirable position, limiting torque induced in the boom. The boom box position sensors may be used to counter-steer the spotter arm to further limit torque. The boom box may also be fitted with rubber springs to permit controlled pile lead deflection while limiting load transmitted to the boom.

Abstract: A control system is provided for use in a power tool. The control system includes: a rotational rate sensor having a resonating mass and a controller electrically connected to the rotational rate sensor. The rotational rate sensor detects lateral displacement of the resonating mass and generates a signal indicative of the detected lateral displacement, such that the lateral displacement is directly proportional to a rotational speed at which the power tool rotates about an axis of the rotary shaft. Based on the generated signal, the controller initiates a protective operation to avoid further undesirable rotation of the power tool. The controller may opt to reduce the torque applied to shaft to a non-zero value that enables the operator to regain control of the tool.

Abstract: A hand-held power tool (1) includes a linear motor (2) having a rotor (3) which is movable along a percussion axis (A) in an axially limited manner between two reversal points (W) and which can be driven by the striking piston (5) of the power tool with the intermediary of an air spring (4), sensors designed for determining the actual state of the rotor (3) and connected to a computer (9) connected via power electronics (33) to at least one field coil (10) of the linear motor (2), with the rotor (3) being displaced against a contact element (11a, 11b) at least at one reversal point (W) and being pressed against the contact element electromagnetically; and a control process for the hand-held power tool.

Abstract: A power tool (1) for driving a working tool (3) that penetrates at least axially into a to-be-machined material (2), and including a signal processor (6, 6?), and a transducer (5) which is suitable for exciting and detecting a high-frequency electromagnetic wave (4) propagating axially along the working tool (3) and which is connected to the signal processor (6, 6?) that is designed to determine the penetration depth (T) of the working tool (3) into the material (2) based on high-frequency electromagnetic waves (4).

Abstract: A rock drilling device has a feed beam (1) and a rock drilling machine (2) movable along the feed beam. The rock drilling machine is fed along the feed beam (1) by a feed line (7), which is routed over a sheave (6) arranged at the movable end (5) of a pressure medium cylinder (3). A further line (8) is arranged between two points (9, 10) which are fixed relative to the movable end of the pressure medium cylinder. The further line (8) is connected to a measuring device (11) which is fixed to the feed beam (1) for measuring displacement of the rock drilling machine (2) along the feed beam.

Abstract: A method for self-programming a computerized power nutrunner control system for tightening a number of similar screw joints to a desired final torque level (MF) is provided. The method includes the steps of: (i) tightening initially at a low speed one of the screw joints up to the final torque level (MF), while detecting and analyzing one or more screw joint characteristics, (ii) adjusting successively during a number of succeeding tightening processes one or more nutrunner operating parameters with respect to the detected and analyzed screw joint characteristics, and (iii) locking the self-programming after the nutrunner operating parameters have been adjusted to accomplish a safe tightening of respective following ones of the screw joints to the final torque level (MF) at a satisfactory short time interval.

Abstract: A depth assembly for use with a hand-held power tool (2) and including a motorized control unit for adjusting a position of a depth-setting member (3) and connectable with an energy source (4) which supplies power thereto, and a micro-controller (6) for controlling the operation of the control unit (5) and connected with a length-determining sensor.

Abstract: A drilling device comprises a drive motor (22), which sets a tool (36) in rotation, and a feed motor (14) which axially displaces the tool. Load sensors (12, 18, 20, 24) detect not only the tool feedrate (V) but also at least two of the three parameters, tool feed force (F), tool torque (M) and tool speed (U). An evaluation and control unit (70) evaluates the above-mentioned parameters and via control units (38, 42) activates the drive motor (22) and the feed motor (14) in such a way that the tool feed force (F) and the tool speed (U) or the tool torque (M) assume values at which the tool feedrate (V) for a specific ground hardness (H) is maximized.

Abstract: Methods and devices are provided for drilling with impregnated diamond drill bits in which the drill bit (30) automatically continues cutting. The speed of a drilling device (3) along a feed device (2) is determined, and the measured value is used for continuously controlling the feed cylinder (10) and a flushing medium pump (29) such that a substantially constant feed rate is achieved while simultaneously maintaining the rotational speed of the drill bit (30) within predetermined limits.

Abstract: A method of regulating drilling conditions applied to a given well bit comprises assaying the compressive strength of the formation in an interval to be drilled by said bit. Wear of critical bit structure of the same size and design as in said given bit and which structure has drilled material of approximately the same compressive strength as that so assayed, is analyzed along with respective drilling data for the worn structure. From said analysis, a power limit for the respective compressive strength, above which power limit excessive wear is likely to occur is determined. Drilling conditions, such as rotary speed and weight-on-bit, at which the given bit is operated are regulated to maintain a desired operating power less than or equal to the power limit. Where several feasible rotary speed/weight-on-bit combinations may result in the desired operating power, these conditions are optimized.

Abstract: An arrangement for controlling the feed motion of the feed beam of a rock drill, the arrangement including sensing elements for detecting the position of the front and for rear end of the rock drill and for controlling the feed and the return motion. In the arrangement of the invention, inductive sensors are mounted in the middle of the feed beam, and indicators are secured to the cylinder sleeve of the feed cylinder so that the position of the cylinder sleeve indicates the position of the front and the rear end of the drill and thus controls the feed motion of the drill.

Abstract: A method for optimizing rock drilling, wherein the drilling is adjusted by means of one or more adjustable parameters such as the feed rate and the rotation rate. In the method, a set value (H.sub.s) of each adjustable parameter is deviated in accordance with a sinusoidal curve while integrating a change caused by the deviation in the penetration rate (x) and adding it to the set value (H.sub.s) so that the set value (H.sub.s) shifts closer to an optimum penetration rate (x.sub.opt).

Abstract: A blasthole drill is provided with sensors for sensing the pressure (AP) applied to and through a drill bit to convey cuttings from the drill hole, the rate of rotation (N) of the drill bit, the torque (RT) required to rotate the bit, the force (FB) applied axially to the bit and the instantaneous vertical position (Y) of the bit. Output signals from the sensors are applied to a microprocessor-based controller which computes the penetration of the drill bit per revolution of the bit (P/R) and the rock specific fracture energy (Es). Using the sensed values and the computed values, the controller produces output signals to increment/decrement the force (FB) applied axially to the drill. The applied axial force is controlled such that the penetration of the bit per revolution remains substantially constant for a given range of values of the rock specific fracture energy but varies for different ranges of the rock specific fracture energy. The rate of rotation of the drill bit is controlled to a reference value.

Abstract: A self-propelled, pneumopercussive, cyclic action, ground penetrating machine (200) has decreased energy consumption and increased average working velocity compared to conventional machines. This is obtained in part by a valve-operated air-distribution mechanism (203) having separate forward and reverse compressed air supply lines (35, 37), which mechanism (203) does not limit the length of the forward and backward strokes of the striker (202). This mechanism allows the backward stroke chamber (75) to be connected with the atmosphere during the entire forward stroke of the striker (202). This eliminates generation of an air buffer in the backward stroke chamber (75) and, consequently, the striker (202) does not lose part of its kinetic energy before impact.

Abstract: A self-propelled, pneumopercussive, cyclic action, ground penetrating machine (200) has decreased energy consumption and increased average working velocity compared to conventional machines. This is obtained in part by a valve-operated air-distribution mechanism (203) having separated forward and reverse compressed air supply lines (35, 37), which mechanism (203) does not limit the length of the forward and backward strokes of the striker (202). This mechanism allows the backward stroke chamber (75) to be connected with the atmosphere during the entire forward stroke of the striker (202). This eliminates generation of an air buffer in the backward stroke chamber (75) and, consequently, the striker (202) does not lose part of its kinetic energy before impact.

Abstract: A technique for providing a continuous underground tunnel between first and second spaced-apart points and for installing new cable, pipe or conduit is disclosed herein. This technique utilizes a boring device including means for boring through soil and a thrust conduit which pushes the boring device through the soil from a first starting point to a second end point as the device bores through the soil, whereby to form a tunnel between the two points. Thereafter, the cable to be installed within the tunnel is attached to the front end of the boring device and the latter is pulled back through the tunnel to its starting point by means of the thrust cable, thereby automatically pulling the new cable in place.

Abstract: A power-wrench bolting spindle (1) is used to insert and tighten screws or nuts. The bolting spindle is driven at one end by a motor through a reduction gear (5) and at its other end a bolting tool is seated. A torque sensor (7) is mounted between the motor and the spindle. During bolting, other essential data besides the bolting torque are ascertained. The bolting spindle is equipped with a depth sensor (24) connected to the regulating circuit to measure the depth of bolting. An angular-speed sensor is connected to the regulating circuit and measures the motor or spindle angular speed. The bolting procedure is carried out in two operational stages separated by a pause, namely an application stage (L) and a tightening stage (Z). Each of these operational stages terminates when a specific shutdown bolting torque is reached.

Abstract: A programmed automatic drill control for optimizing the drilling of subterranean holes by large drilling machinery such as blast hole drills. Sensing means are provided to sense a first set of drilling parameter limits to effect maximum r.p.m. of the motor to rotate the pipe drilling bit and to sense a second set of drilling parameter limits to effect a maximum rate for the motor to drive the hoist pull-down mechanism. These conditions will prevail until a sensed limit is reached or the drilling conditions require operation along a torque or force limit set value. When a limit is reached, the control will regulate at a value of r.p.m. or rate which is consistent with maintaining operation at the limit value.

Abstract: According to the applicant's invention a load detector is used, in which a load sensor and a vibration sensor are combined using an AND gate. A load signal from the load detector is used for the feedback control of the cutter drum height and double ranging drum cutter running speed, so that a person who is not skilled can operate the double ranging drum cutter while preventing overload acting on the cutter drum.

Abstract: A method for controlling drilling process based on the use of an adaptive model of drilling process comprises two control modes of which one is a multicycle rock formation trial mode and the other mode is a drilling mode proper. During the first cycle of the trial mode the drilling speed is determined on the basis of pre-set values of controlled parameters and approximate values of coefficients of the adaptive model being corrected and this drilling speed is compared to the value of drilling speed as measured during the first cycle; and corrected values of a respective coefficient of the adaptive model being corrected are formed based on the comparison results; and, taking into account these values, the values of control signals close to optimum values are determined which are the settings for acting on the bit during the next trial mode cycle. In each next cycle the corrected coefficients of the preceding cycle are used for determining control signals.

Abstract: A system for automatic control of a rotary drill comprises a unit for computing the value of drilling tool penetration per single revolution, said unit connected with its inputs to respective transducers and with its output--to an element for comparison of the current value of drilling tool penetration per single revolution thereof with the preset value of such penetration. The preset value of drilling tool penetration is computed by computer means connected with its inputs to respective transducers and to setters of input parameters. With its outputs, the computer means is connected to the element for comparison of the current value of drilling tool penetration per single revolution thereof with the preset value of such penetration, to regulators of drilling tool axial load and rotation frequency and to an element for comparison of the current value of specific drillability of the rock being drilled with the preset value of specific drillability.

Abstract: A drilling machine comprises a quill, pneumatic cylinder for reciprocating the quill in the forward and backward direction, a feed control device which includes a liquid cylinder parallelly disposed to the quill and provided with a piston assembly with a projecting portion engageable with the quill for controlling the advancing speed of the quill, one-way clutch for allowing the piston assembly only the forward movement thereof by engaging with the projecting portion of the piston assembly, and an operation control device for repeatedly reciprocating the quill. The quill is advanced firstly at a rapid speed; upon engaging with the projecting portion of the piston assembly, the quill is advanced at a regulated speed by the liquid cylinder. When the quill has completed several times of reciprocation movement under the control of the operation control device, one working cycle is finished.

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: A rock drill assembly and more particularly a rock drill assembly having improved fluid power means therefor.

Abstract: A control system is provided for use in a power tool. The control system includes: a rotational rate sensor having a resonating mass and a controller electrically connected to the rotational rate sensor. The rotational rate sensor detects lateral displacement of the resonating mass and generates a signal indicative of the detected lateral displacement, such that the lateral displacement is directly proportional to a rotational speed at which the power tool rotates about an axis of the rotary shaft. Based on the generated signal, the controller initiates a protective operation to avoid further undesirable rotation of the power tool. The controller may opt to reduce the torque applied to shaft to a non-zero value that enables the operator to regain control of the tool.

Abstract: A control system is provided for use in a power tool. The control system includes: a rotational rate sensor having a resonating mass and a controller electrically connected to the rotational rate sensor. The rotational rate sensor detects lateral displacement of the resonating mass and generates a signal indicative of the detected lateral displacement, such that the lateral displacement is directly proportional to a rotational speed at which the power tool rotates about an axis of the rotary shaft. Based on the generated signal, the controller initiates a protective operation to avoid further undesirable rotation of the power tool. The controller may opt to reduce the torque applied to shaft to a non-zero value that enables the operator to regain control of the tool.

Abstract: A control system is provided for use in a power tool. The control system includes: a rotational rate sensor having a resonating mass and a controller electrically connected to the rotational rate sensor. The rotational rate sensor detects lateral displacement of the resonating mass and generates a signal indicative of the detected lateral displacement, such that the lateral displacement is directly proportional to a rotational speed at which the power tool rotates about an axis of the rotary shaft. Based on the generated signal, the controller initiates a protective operation to avoid further undesirable rotation of the power tool. The controller may opt to reduce the torque applied to shaft to a non-zero value that enables the operator to regain control of the tool.