Abstract: In one aspect, a sprinkler is provided having a nozzle, a deflector that receives fluid flow from the nozzle, and a friction brake assembly that controls rotation of a deflector. The friction brake assembly is releasably connected to the frame in order to enhance serviceability of the sprinkler. In another aspect, a sprinkler is provided having a frame, a deflector rotatably connected to the frame, a nozzle, and a nozzle socket of the frame. The nozzle and nozzle socket have interlocking portions that releasably connect the nozzle to the frame. The nozzle may be easily removed for servicing. Further, the nozzle socket can be configured to receive a plurality of nozzles having different flow characteristics. A nozzle can be selected and utilized with the sprinkler according to the desired application for the sprinkler.

Abstract: In one aspect, a sprinkler is provided having a nozzle, a deflector that receives fluid flow from the nozzle, and a friction or viscous brake assembly that controls rotation of a deflector. The friction or viscous brake assembly is releasably connected to the frame in order to enhance serviceability of the sprinkler. In another aspect, a sprinkler is provided having a frame, a deflector rotatably connected to the frame, a nozzle, and a nozzle socket of the frame. The nozzle and nozzle socket have interlocking portions that releasably connect the nozzle to the frame. The nozzle may be easily removed for servicing. Further, the nozzle socket can be configured to receive a plurality of nozzles having different flow characteristics. A nozzle can be selected and utilized with the sprinkler according to the desired application for the sprinkler.

Abstract: In one aspect, a sprinkler is provided having a nozzle, a deflector that receives fluid flow from the nozzle, and a friction brake assembly that controls rotation of a deflector. The friction brake assembly is releasably connected to the frame in order to enhance serviceability of the sprinkler. In another aspect, a sprinkler is provided having a frame, a deflector rotatably connected to the frame, a nozzle, and a nozzle socket of the frame. The nozzle and nozzle socket have interlocking portions that releasably connect the nozzle to the frame. The nozzle may be easily removed for servicing. Further, the nozzle socket can be configured to receive a plurality of nozzles having different flow characteristics. A nozzle can be selected and utilized with the sprinkler according to the desired application for the sprinkler.

Abstract: The invention relates to the field of machinery, and in particular relates to a small-resistance and high-efficiency digging apparatus with multiple layers of impact heads, which is applicable to the digging field or the field of engineering machinery. The apparatus comprises an impact power box and impact heads, wherein the impact heads are arranged at one end or two ends of the impact power box, more than two impact heads are arranged at each end of the impact power box, and the more than two impact heads are arranged vertically and/or bilaterally to increase the digging height and/or digging width. The apparatus is reliable in performance, strong in manufacturability, simple to machine and manufacture and long in service life.

Abstract: A high-efficiency mining machine for percussing falling-materials without trapping materials. Also disclosed is a high-efficiency mining method for percussing falling-materials without trapping materials. The mining machine has a simple structure and works in a reliable way.

Abstract: A rolling friction or suspension friction impact mining method and a wear-resistant impact mining machine using said method. The mining machine comprises a reciprocating impact part (3). The reciprocating impact part comprises an impact drive device (4), a rolling reciprocating device, and an impact head (6). The rolling reciprocating device comprises a rubbing body (38), a rubbing body support (39), an impact guiding element (5.1), and a position-limiting mechanism. The rubbing body (5.3) are disposed between the robbing body support (39) and the impact guiding element (5.1), and inside of the position-limiting mechanism to form rolling guiding.

Abstract: The invention relates to a tool for a breaking hammer, a breaking hammer, and the use of a breaking hammer. The breaking hammer includes a percussion device, the percussion piston of which providing impacts to the tool for breaking rock. An impact surface of the tool has a curved form surface that has a radius of curvature and a center axis on the longitudinal axis of the tool. The direction of the centre axis is transverse to the plane through the longitudinal axis of the boom of a work machine.

Abstract: A concrete hammer having a grapple associated therewith is provided which is mounted on the forward end of the boom arms of a skid-steer vehicle. The grapple is selectively movable between open and closed positions. When the grapple is in its open position, the concrete slab may be positioned between the concrete hammer and the grapple with the grapple then being closed to maintain the concrete slab on the upper end of the concrete hammer. The concrete slab may then be moved to a truck for disposal.

Abstract: A rock claw is provided for a demolition hammer. The rock claw may be a separate component attachable to the external surface of the hammer housing. The rock claw may include a first portion with a first distal end and a first proximal end and a second portion with a second distal end and a second proximal end. The first proximal end is joined to the second proximal end to form an elbow and the second distal end having a first leg spaced apart from a second leg.

Abstract: A percussion tool for a demolishing hammer or the like, comprises an elongated body that has a first portion aimed to be connected with the demolishing hammer and a second portion, opposite to the first portion, that includes a working bit. The two portions are made of mutually different materials and are rigidly connected by means of a connection member that can be applied outside the portions. Both portions of the tool have formations that can be engaged by corresponding formations of the connection member.

Abstract: A continuous mining method includes operating a vibratory milling machine having a milling head, a base, and a milling tool to oscillate the milling head in a substantially linear reciprocating fashion relative to the base to move the milling tool along a milling axis; and advancing the vibratory milling machine in a work piece in a cutting direction and wherein milling axis is oriented at an attack angle relative to the cutting direction, the attack angle being between about 0 and about 40 degrees.

Abstract: A vibratory milling machine has a vibratory housing confined to substantially linear reciprocating motion relative to a base, causing a tool carried by the housing to impact a mineral formation or other work piece substantially in a primary milling direction. The vibratory motion may be generated by two or more eccentrically-weighted rotors rotated by a common drive mechanism. The rotors may be arranged in pairs with the rotors of each pair rotating in opposite directions about parallel axes so that lateral oscillations cancel and longitudinal vibrations in the milling direction reinforce one another. In one embodiment, a hydrostatic fluid bearing is provided between the outer surface of each rotor and the housing.

Abstract: A blade assembly for an earthworking implement has a set of teeth that are independently slideable within guides. The teeth slide to conform to an undulating surface and permit scraping of the surface.

Abstract: A boom arrangement (1) for a scaling device including a scaling boom for supporting a scaling hammer, wherein the scaling boom is arranged for connection to a carrier vehicle, is distinguished in that the scaling boom (4,5) is pivotally supported by a boom column unit (3), which is arranged for pivotal connection to the carrier vehicle, that the boom column unit (3)includes a boom column (7), and a column bar unit (8) extending at a distance from that element, that the boom column and the column bar unit are pivotally connected to a column link (9) for forming a four-link mechanism, and that the column link (9) supports a bearing for a boom lift cylinder (12). The invention also concerns a scaling device.

Abstract: A boom arrangement (1) for a scaling device including a scaling boom for supporting a scaling hammer, wherein the scaling boom is arranged for connection to a carrier vehicle, is distinguished in that the scaling boom (4,5) is pivotally supported by a boom column unit (3), which is arranged for pivotal connection to the carrier vehicle, that the boom column unit (3)includes a boom column (7), and a column bar unit (8) extending at a distance from that element, that the boom column and the column bar unit are pivotally connected to a column link (9) for forming a four-link mechanism, and that the column link (9) supports a bearing for a boom lift cylinder (12) . The invention also concerns a scaling device.

Abstract: A formation breaking apparatus with increased wear-resistance is disclosed. In one aspect of the invention, the apparatus has an assembly attached to an end of an articulated arm. The assembly has an actuator in mechanical communication with an axially guided penetrator. The penetrator may have a body intermediate a proximate end and a distal end; the proximate end being adapted to communicate with the actuator, and the distal end comprising a hard material with a hardness of at least 63 HRc.

Abstract: A mine scaling vehicle for use in removing loose materials from the roof and walls of underground mines includes an articulated frame with a turntable mounted on a forward portion of the frame and a drive system mounted on the back portion of the frame. The turntable rotatably supports an operators cab and a boom carrying a scaling pick, with the operators cab being located centered rearwardly of the boom to provide improved scaling visability for the operator. The drive system and a hydraulic control system of the mine scaling vehicle are mounted on the frame located below a plane of the turntable to provide a low center of gravity of the mine scaling vehicle.

Abstract: A scaling apparatus comprises a hammer component and a pick component which includes a tooth. The apparatus also includes a mechanism for moving the pick component with respect to the hammer component to thereby impart a scaling force to and through the tooth. In a preferred embodiment of the invention, the pick component includes a pick body comprising a first pivot having a pivot axis and a tooth mounted on the pick body. In this embodiment of the invention, the hammer component includes a hammer housing and a second pivot mounted within the housing and adapted to pivotally engage the first pivot of the pick body. This embodiment of the invention also includes a mechanism for rotating the pick body relative to the hammer component so as to impart a scaling force.

Abstract: A fluid-powered impact vibrator (5), in particular a hydraulic hammer, comprising a fluid-powered percussion hammer (8) with a percussion piston (18) that is moved back and forth under the effect of a control means (10) and comprising a guide unit (7) on which the percussion hammer is supported, wherein the impact vibrator is additionally provided with a control valve, designed as a pressure monitor, for adaptation to the supplied input power. The control valve preferably is a pressure shut-off valve or a pressure-limiting valve (25) that is connected to the input pressure line (3) provided with the operating pressure, and automatically stops the percussion hammer (8) if the operating pressure resulting from the input power exceeds a specified maximum value. To stop the percussion hammer (8), either the pressure line (3) is blocked or the control means (10) is held in one of its end positions, i.e., the operating stroke or the return stroke positions.

Abstract: It is suggested to machine contaminated surfaces, in particular radioactively contaminated concrete surfaces and masonry with pneumatically actuated striking tools. It has been shown that this is an extremely low-dust machining method with which the essentially the particles are struck off in the size order of 0.2 to 2.0 mm. The method may be realized with a device (1) with which in a housing (2) several chambers are arranged over one another. Most preferred at the top a pressurized air feed chamber (10) is fed via a pressurized air connection (3). Therebelow there is located a pressurized air suction chamber (12) which comprises a suction connection (4). At the bottom there is arranged a collecting chamber in which chisel-like hammer bolts (51) are effective. The hammer bolts which are part of the striking tools (5) project out of the housing (2).

Abstract: The present invention discloses an apparatus and method for imaging and clearing an ore pass hang-up. The apparatus includes: a platform that is movable along generally a longitudinal direction of an ore pass; a controllable propulsion unit capable of propelling the platform within the ore pass and to the location of the hang-up; an imaging unit capable of generating an image of the ore pass as the apparatus is moved trough the ore pass, wherein the image is transmittable to a remove viewer; extensible, remotely controllable immobilizing units affixed to the platform; and a remotely controllable unit for clearing the ore pass hang-up. Once in place the apparatus is used to break up or clear the hang-up by, for example, directing blows to the hang-up, directing high pressure fluids to the hang-up, and using an explosive charge.

Abstract: A pavement demolition hammer is removably fastened to a loader and includes a mounting plate securable to the loader. A framework is attached to the mounting plate and is provided with a lower spring and an upper spring spaced from the lower spring. A hammer handle has a proximal end pivotally mounted to the framework for swinging movement between the lower spring and the upper spring, and a distal end equipped with a hammer head adapted to engage the pavement. The loader applies a moving force to the mounting plate such that the lower spring is accelerated against the bottom of the handle causing the handle and the hammer head to swing upwardly from a pavement surface to be broken towards the upper spring. The handle and the hammer head return to the pavement surface either by gravity or acceleration from the upper spring against the top of the handle in a manner that the hammer head impacts and demolishes the pavement surface.

Abstract: A hammer-ripper system for use with the mounting on the boom arm, of an excavator/backhoe, of a conventional hydraulically-operated hammer fitted with a “shortened” chisel. A “ripping-type” device like a chisel tooth mounts to a lever with its pivot point attached to the side of the hammer. One end of the lever extends to be impacted by under the shortened chisel, while the other end extends inward. Thus, the tooth end can be placed under embedded boulders and used to hammer (using the transmitted reciprocating action of the hydraulic hammer), and pry or break up the boulders from underneath with the combined hammering and ripping action.

Abstract: It is suggested to machine contaminated surfaces, in particular radioactively contaminated concrete surfaces and masonry with pneumatically actuated striking tools. It has been shown that this is an extremely low-dust machining method with which the essentially the particles are struck off in the size order of 0.2 to 2.0 mm.

Abstract: The breaker device for removing the tops of columns comprises a support structure composed of a plurality identical chain elements reciprocally linked by link couplings to form a closed chain which can surround a column which is to be topped. Each chain element bears a jackhammer provided with a plurality of interchangeable breaker punches, of varying lengths. Each chain element exhibits a plurality of holes which are distanced from the link couplings and which are for linking the chain elements. Each hole is aligned with a corresponding hole of an adjacent chain element. A pin is used for blocking adjacent chain elements in predetermined positions. The invention is useful for breaking the stop of a reinforced-concrete column without damaging the reinforcement elements thereof. The device can be adapted to columns having different diameters.

Abstract: A down hole hammer comprising a cylindrical casing defining a piston chamber between a top sub at one end and a drill bit support at the other end, a piston within the piston chamber for reciprocation between the one and other end, the piston having a central portion which is sealingly engaged with the internal wall of the casing, one end portion of the piston being intended to impact on the drill bit with movement to an impact position at which position the one end portion sealingly defines a first space at the one end of the piston chamber, the internal wall of the casing adjacent the top sub having two sets of axially spaced fluid ports, the piston adapted to cooperate with a first set of the fluid ports to admit fluid into the first space when the piston is in the impact position and cause movement of the piston to a raised position where the piston is in spaced relation from the drill bit support, the piston adapted to cooperate with a second set of said set of fluid ports to admit fluid into a second sp

Abstract: A breaker, used for breaking target hard objects, such as reinforced concrete structures, rocks or hard soil, using pneumatic and hydraulic pressure, is disclosed. In the breaker, the piston is multi-stepped to form first, second and third oil chambers between the piston and the cylinder. First, second, third and fourth oil paths are formed in the sidewall of the cylinder. The first oil path extends from the oil inlet port to the first chamber, thus feeding pressurized oil from an external oil source to the first chamber. A valve chamber is formed in the sidewall of the cylinder. The second oil path allows the valve chamber to selectively communicate with the second chamber. A directional control valve unit is installed within the valve chamber, and selectively returns the pressurized oil from the first chamber to the valve chamber prior to feeding the oil from the valve chamber to the second chamber through a plurality of oil ports and the second oil path.

Abstract: A rotatable cutting drum to be mounted on a machine for mining or for milling a surface such as a roadway. The drum is equipped with a set of movable bits or chisels which impact on the surface to be cut. The movable bits or chisels are impacted by pendulums mounted on a rotating cylinder mounted inside of the drum so that a percussive force is generated to assist cutting.

Abstract: The present invention is directed to a method for breaking rock and other hard materials using small-charged blasting techniques followed by a mechanical impact breaker. In small-charge blasting techniques, a gas is released into the bottom of a sealed hole located at a free surface of the hard material. The gas pressure rises rapidly in the hole until the gas pressure causes the hard material to fracture. In one embodiment, the a deeper hole is drilled and/or a small amount of blasting agent is used to cause the formation of a network of subsurface fractures while either not removing any of the rock or removing the rock with very low energy flyrock. In another embodiment, only the central portion of the face is broken and/or removed by blasting. The impact breaker is then used to complete fracturing and removal of the material.

Abstract: A portable mechanized scaling bar for the dislodging of unstable rocks in the galleries of subterranean mines provided with a telescopic handle of one (1) to two (2) meters in length terminated by a periodic displacement hitting piston, and a scaling tool adapted to the handle and comprising an anvil with a first longitudinal axis in line with the handle and having a penetrating portion including a point with a circular section, an angular stem with a convex back and concave face, an S-shape connecting the stem with an elongated anvil wherein when the point is displaced axially between rocks a lever is formed for dislodging the rocks. This tool generates a lever effect while penetrating between unstable rocks and rapidly dislodges them while minimizing efforts by the operator.

Abstract: The digging apparatus support boom of a continuous excavating machine is vibrated in a directional mode so as to enhance digging efficiency. Directionally compliant mounting of the boom isolates this vibration from the machine proper while allowing unimpaired application of digging torque and crowd forces.

Abstract: A rectangular shield excavating machine comprises a quadrangularly tubular shield body having a space for receiving an excavated matter at the front end, a rotor disposed in the space so as to be capable of being rotated onward and backward angularly around an axis extending in the direction orthogonal to a pair of facing exterior portions of the body, and excavating means disposed in the body, drive means for rotating onward and backward the rotor angularly around the axis, and for driving the excavating means. Large gravels contained in the excavated matter are crushed by being put between the rotor and a member defining the space with the rotationally reciprocating motion of the rotor.

Abstract: A mounting bracket for mounting a working device to a boom of a carrier includes a base, flanges for attaching the bracket to the boom, and ears for attaching the working device to the bracket. The ears each define a hole for pivotally coupling the working device thereto for free pivotal movement about a single axis to alleviate the generation of excessive side forces. The bracket further includes stops to limit the free angular movement so that the working device can be oriented at an inclination and so that it may be used to pry pieces of the worked material.

Abstract: An impact assisted segmented cutterhead device is provided for cutting various surfaces from coal to granite. The device comprises a plurality of cutting bit segments deployed in side by side relationship to form a continuous cutting face and a plurality of impactors individually associated with respective cutting bit segments. An impactor rod of each impactor connects that impactor to the corresponding cutting bit segment. A plurality of shock mounts dampening the vibration from the associated impactor. Mounting brackets are used in mounting the cutterhead to a base machine.

Abstract: A system is provided for forcibly drawing a flexibly-supported, acute angled, wedge under an existing stretch of a predetermined width of reinforced pavement to initiate removal thereof from the ground below. Gravity-assisted impact hammers apply downward blows of a controlled magnitude and at a predetermined rate onto an upper surface of the reinforced pavement, to crack the same across the entire width thereof over the wedge being driven therebelow. The wedge is flexibly supported, with a predetermined amount of elasticity in the up-and-down direction, so that it essentially "floats" and facilitates absorption of the impact forces by the reinforced pavement to be cracked thereby. Cracked reinforced pavement is subjected to further blows by a hammer coacting with a set of bars transverse thereto, to forcibly render a bulk component of the reinforced pavement into small pieces separated from reinforcement material contained therein.

Abstract: A low velocity, high mass ram is connected to the cutting tool. The cutting tool has an array of impact forward and side buttons or bars which form chip-forming spaces there between. The side buttons or bars advantageously cut a gage in the slot. A method of slot kerfing which cuts the kerf on an angle.

Abstract: An improved ripper using a hydraulic hammer with a rotating long service life hammer tool is provided. The tool is cylindrical with a large cylindrical upper portion and a central portion of reduced diameter. The tool is retained in the hammer by means of a pin passing through the tool cavity of the hammer housing which prevents passage of the large upper portion.

Abstract: A bucket system which includes a bucket having a bottom with a digging edge. An impact-type penetration member projects beyond the digging edge to penetrate the surface of a body being excavated. The free edge of the penetration member is continuous and is at least as long as the bucket is wide. Bearing surfaces and restraint surfaces enable the penetration member to be driven by an impact member with reduced wear, and with the ability to respond to irregularities in the surface being penetrated. Preferably the penetration member includes a pair of deflector wings spaced apart farther than the sides of the bucket.

Abstract: A bucket system which includes a bucket having a bottom with a digging edge. An impact-type penetration member projects beyond the digging edge to penetrate the surface of a body being excavated. The free edge of the penetration member is continuous and is at least as long as the bucket is wide. Bearing surfaces and restraint surfaces enable the penetration member to be driven by an impact member with reduced wear, and with the ability to respond to irregularities in the surface being penetrated.

Abstract: The present invention is a device for removing boulders loosened by an explosion, from the hanging roof of a mining gallery. The device is a pole which supports a pneumatic hammer and a striking head at one end thereof and a gripping handle at its opposite end. The handle has a trigger mechanism for remote control of the pneumatic hammer. The inner section of the striking head is a formation of hollow, honeycombed cells, for reducing the weight of the striking head.

Abstract: A machine for driving workings in hard rocks comprises a movable carrier (1) having a boom (2) to which is secured a frame (4). An implement (9) having a hammer piston (10) is mounted in the frame (4) by pins (8). The pins (8) have support members (7) cooperating with piston rods (12) of shock-absorbing elements (11) comprising cylinders. Each shock-absorbing elements (11) has a space filled with a compressible fluid in which the end face of the piston rod (12) is received, and a first and second dashpot spaces filled with a non-compressible fluid which communicate with one another through a throttling device. The piston rod (12) has an enlarged piston-like portion which forces the non-compressible fluid to overlfow through the throttling device between the first and second dashpot spaces during movement of the piston rod (12).

Abstract: A method for drilling a hole in a hard material such as rock. According to this method, the rock is fragmented by impact along spaced-apart, parallel paths while it is simultaneous fragmented by shear between these paths. An apparatus for carrying out this method is also disclosed.

Abstract: Hard rock trenching apparatus comprised of a pair of spaced apart diamond toothed cutting blades mounted for rotation in combination with a hydraulically operated breakout tool having a chisel face supported behind the cutting blades in a plane located intervening within the spacing between the cutting blades. The tool is continuously operable for removing the center core remaining between the blades while an adjustable linkage enables positioning the chisel of the tool at or above the cutting plane of the blades.

Abstract: An apparatus for impacting on a hard surface such as concrete so as to break up the hard surface. This apparatus comprises a frame having a bed and an upstanding rail assembly projecting from the bed, a drive shoe, a hammer means attached to the rail assembly so as to be movable in only one direction and operatively connected to the drive shoe for impacting upon the drive shoe. The drive shoe lies adjacent the surface so that upon impact from the hammer means, the shoe forcefully impacts the surface so as to break up the surface. An adjustment means is used to selectively position the drive shoe relative to the hammer means.

Abstract: A guide member is mounted to the housing frame to be integrated into the boom or shovel arm of a hydraulic excavator to control an additional implement in the form of a clearing blade or clearing shovel which is displaceable on the guide member between a rest position laterally abutting the housing frame and an operational position pointing approximately in the same direction as the actual hammer and which can be locked in place at least in each of the end positions.

Abstract: For cutting rock by means of cutting head (1) having its bits (24) cooperating over a limited axial shifting stroke (a) with a cylinder-piston-aggregate, for example a valve (18), it is proposed to intermittently subject the cylinder-piston-aggregate to the action of pressurized fluid, thus exposing the bit (24) during its engaging the rock to percussion forces. During the phases lacking any action of pressurized fluid onto the cylinder-piston-aggregate, the bit (24) shall be pushed into its starting position. This embodiment can be realized with both hydraulic and pneumatic cylinder-piston-aggregates, noting that in case of an embodiment having a hydraulic cylinder-piston-aggregate it is preferred to design this cylinder-piston-aggregate as a valve (18) which simultaneously provides the possibility to expel pressurized liquid via a spraying nozzle (32) onto the mine face. (FIG.

Abstract: The invention disclosed herein is a mining machine with an adjustable hood-scoop assembly. The machine provides a means to remove coal from the face of a seam and extract the removed coal to a position removed from the mining area utilizing a vacuum system. The instant mining machine encloses the total face of the mine seam and acts to remove all solid and gaseous material from the mining area. Use of this apparatus in the mining of coal will provide better insurance for a healthy methane-free environment for the miner. The hood-scoop assembly is constructed to provide both horizontal and vertical moving plates so as to encompass totally the area contacted by the coal removal means, such as a multitude of air hammers. The machine is both braced and made mobile by means of vertical hydraulic jacks. Hydraulic cylinder means on the hood-scoop assembly are provided with specific trackways to insure four-way movement of the adjustable plates as shown in FIGS. 1, 2, 4 and 7.

Abstract: A tool assembly in which the tool holder 6 forms a relatively small volume of metal thereby facilitating brazing of the tool bits (21, 23) and inexpensive replacement.

Abstract: For progressively breaking-in-place concrete of roadways or the like, a vertically extending diesel power driver, of a type used as a pile driver, but with a concrete-breaking shoe forming its lower end, is advanced by a towed chassis. Guide angles at the upper portion of the power driver, cooperating with a guide bar vertically disposed, guide the power driver in its conventional rythmic bobbing, with sufficient looseness to permit the power driver to have a pendulum like swinging action. This swinging action results from relatively intermittent movement of the bottom portion of the power driver while the top portion is advanced more steadily by the chassis. Shoe-towing means extend forwardly from the shoe to a hanging link which is resiliently biased forwardly to tow the shoe. The biasing is provided by long-throw cushions. The forwardly extending shoe-towing means is flexible, to prevent damage when the shoe is driven deeply.

Abstract: The invention relates to a chisel alignment unit for a facility for breaking the crust of solidified electrolyte on an electrolytic cell, in particular on a cell for producing aluminum. A mechanically stable alignment box extends from the under side of the chisel in its non-working position to the piston rod. The chisel features at least one vertical alignment surface which is in contact with at least one alignment roll mounted on the alignment box by means of roller bearings. A wiper for removing electrolyte from the chisel is mounted below the alignment rolls and extends over the full width of the alignment surface or surfaces.