Abstract: A mounting system for repeatedly attaching and detaching an optical sighting device having a sighting axis to and from a supporting base having a base axis without interfering with the alignment between the two axes when the sighting device is in place on the base. The system utilizes a plurality of precisely spaced locating points between the holder of the sighting device and the supporting base. It is highly precise, relatively simple in construction, and may be attached and detached without tools. The system finds particular but not exclusive utility for mounting a telescopic sight on a rifle or other firearm.

Abstract: A dryer for printed material and the like including a frame structure with upper and lower heater panel assemblies vertically movably mounted therein. Each heater panel assembly includes a plurality of quartz tube heat lamps. The heater panel assemblies are reciprocated between open and closed positions by a pneumatic cylinder. An air handling system includes a drying air subsystem, a cooling air subsystem and an exhaust system. A control system includes an infrared detector for determining the temperature of printed material in the dryer and automatically adjusts the output of the heat lamps to maintain a predetermined web temperature.

Abstract: A method of dehydrating metal pieces including immersing the pieces in an oil heated to or above the boiling point of water for a time to boil off the water and then removing the pieces from the oil. An apparatus for the dehydration of metal pieces includes a container for carrying the pieces to be dehydrated, a receptacle for holding oil in which the chips are to be immersed, means for heating the oil to or about the boiling point of water, and means for introducing the container into the receptacle to immerse the pieces in the oil and removing the container and pieces from the oil.

Abstract: A solar powered food dryer that may be used indoors is provided when a solar heated convection column is used to produce a draft of air and by means of this draft to draw air from a solar collector through a food drying chamber in such a way that the hot air from the collector is drawn over the food in the drying chamber and hot air ducting of the airstream provides a means of remoting the drying chamber to a sanitary and convenient place while leaving both the air heater and the draft generating convection column in a place exposed to solar radiation.

Abstract: A relatively stationary pipe or conduit, for the removal of a condensate or liquid from the interior of a steam heated rotatable drying drum or cylinder assembly and adapted for connection to a source of relatively low or sub-atmospheric pressure, has an inner end portion, disposed within the drum or cylinder assembly, which is provided with an inlet opening or port disposed in juxtaposition and close proximity to an inner cylindrical surface of the cylinder assembly; the inlet opening has a generally rearwardly situated wall which is substantially inclined as with respect to a radial plane of the cylinder assembly as to provide for enhanced transitional flow of the condensate from the inner cylindrical surface of the cylinder assembly to the condensate-removing pipe or conduit.

Abstract: A true moc shoe has a vamp with unitary bottom and side portions, and a sole coextensive with the vamp bottom. The vamp is stitched directly to the sole, and a cushioning element is interposed therebetween. The cushioning element has a shape substantially coextensive with the sole, and the peripheral edges of the element are spaced from the stitches. The sole may be formed of flexible rubber.

Abstract: This invention pertains to soles for boots and shoes. More particularly, it pertains to a sole that is useful for mountain climbing boots, hiking boots, walking shoes, and work shoes.

Abstract: A skiing boot comprises a gaiter, which is pivotally movable relative to the foot part, and a spring element, which is disposed between the foot part and the gaiter and under an adjustable initial stress. The spring element influences the movement of the gaiter relative to the foot part in the direction of skiing. Mutually independent means are provided for adjusting the initial stress of the spring element and for adjusting the forward lean of the gaiter relative to the foot part. A releasable adjusting device for fixing the inclination of the gaiter is provided between the foot part and the gaiter.

Abstract: A two-piece cutting edge construction wherein a plurality of adapters are mounted on the mold board each having releasably locked thereto a cutting edge; the sidewalls of the adapters and cutting edges being recessed for the receipt of longitudinally (forwardly/rearwardly) stabilizing pins; the lock for releasably coupling the cutting edge to the adapter including two legs resiliently inner connected by a compression spring with the lock being insertable and removable by forces extending transversely of the forward/rearward mounting and unmounting direction of the cutting edge.

Abstract: A workpiece stand including a base and an upright standard with a lower end attached to the base and an upper end. A universal joint assembly is mounted on the standard upper end and includes a tension spring and first and second mechanisms for adjusting the tension of the tension spring. A cross arm is connected at its middle to the universal joint assembly and includes opposite ends. A pair of clamp assemblies are attached to the cross arm at its opposite ends. The clamp assemblies are adapted for securing a frame for a workpiece.

Abstract: A dry fire unit which is placed in a gun in place of the firing pin is provided. The firing pin is removed and an energy-absorbing wedge of the dry fire unit is placed into the gun in lieu of the firing pin such that the dry fire unit is struck by the hammer of the gun when its trigger is pulled. The dry fire unit is an energy-absorbing wedge that allows the gun to be dry fired without cracking or peening the hammer. Further, since the dry fire unit replaces the firing pin, it is not necessary to remove ammunition from the gun since there is no possibility of the gun being fired.

Abstract: A shooting bench including an upper cross member having legs pivotally attached thereto to allow for collapsing of the legs for carrying of the shooting bench. A brace secures one of the legs in an extended position during use of the bench. The other leg carries a rest member at its upper end which is adjustable for elevation by pivoting the leg about its pivotable attachment to the upper cross member.

Abstract: A method and apparatus for forming and holding fish bait such as cheese or the like and for easy insertion of a fish hook therein. A flat mold member is provided with a plurality of indentations therein of generally cylindrical shape and with a generally hemispherical bottom with a vent hole therethrough communicating with the atmosphere. The indentations are sized to receive a fish hook, preferably a treble hook, therein. The cheese is spread across the mold member and into the indentations, being scraped level with the top thereof. Trapped air can escape through the vent hole. A treble hook can then be inserted into a cheese-filled indentation and then be withdrawn with the cheese adhering thereto. The vent hole allows air to re-enter so that the baited hook can be removed. A covered container is also provided for holding the mold member with the bait in the indentations for carrying in a safe manner. The bait is applied to the hooks as needed at time of use.

Abstract: A fishing net includes a photoconductive cable comprising a plurality of optical fibers having light-emitting portions, wherein said light-emitting portions are divided into a first group adapted to emit light having favorable influence upon fish and a second group adapted to emit light having an adverse influence upon fish. The direction of light emanating from said first group of light-emitting portions is counter to that of light emanating from said second group of light-emitting portions. Fish travel into the net influenced by the light of the first group and are discouraged from leaving by the light of the second group.

Abstract: A casting rod includes an elongated piston chamber tube and a connected guide tube for enclosing and guiding a push rod to accelerate and project a fishing lure or other weighted device attached to a line. The push rod has a piston fixed to its rearward end for coaction with the chamber tube, and the rod projects through the guide tube having a mounting tube at its exterior exposed end which is the rod tip. A weighted device has an axial pin received within the mounting tube and attached to the line which passes through a line aperture in the mounting tube. The rod includes a valve housing and handle at its base end, the handle enclosing a CO.sub.2 cartridge which is pierced to pressurize the valve chamber. A valve interposed between the valve chamber and the cylinder chamber is opened momentarily by a firing pin impacted by a hammer to pass a charge of pressurized gas to the piston chamber to accelerate the push rod and project the lure.

Abstract: A fish attractor blade adapted to remain substantially stationary within the water after the fish strikes or grabs the hook and "runs" with the line through the water.

Abstract: Improved fishing equipment includes a lure and apparatus for connecting the lure to a fishing line, the lure body being formed with a 180.degree. twist about its longitudinal axis and having openings formed along the sides thereof and away from the axis to provide turbulence when the lure revolves about the axis. The integral or separate connecting structure includes, in addition to a snap and a swivel, a flat anti-twist element extending on both sides of the axis so as to be acted upon by water resistance on both sides of the axis, the anti-twist element being formed to simulate a minnow being attacked by the lure.

Abstract: A multiple chamber fly trap contains approximately concentric screens defining a region within the inner screen into which the flies enter for the bait, an annular second region between the screens into which the flies enter to escape to the light, and a third region below the second region into which the flies drop after exhaustion. A plurality of openings between the consecutive regions allow passage of the flies from the first to the second to the third and into a removable collector which is preferably a disposable bag.

Abstract: A frost minimization or prevention machine comprising a fan to draw air downwardly from above the crop to be protected and disperse the air horizontally over the crop. Ideally the fan draws down warmer air from above the inversion layer.

Abstract: An automatic door operator for a swing door supported by a door supporting frame to swing about a vertical axis. The automatic door operator includes a mechanism for opening and closing the swing door, a drive for driving the door opening and closing mechanism to open the swing door, the drive including a prime mover for driving the door opening and closing mechanism, a door closer including a resilient device for storing part of mechanical energy provided by the drive in opening the swing door and for exerting driving force on the door opening and closing means by using the stored mechanical energy to close the door, a unit for electrically controlling the drive to swing the swing door, and a sensor for sensing a body accessing the door and thereby providing an electric signal to open the door to the controlling unit.

Abstract: A drum is mounted to rotate about its drum axis. A pair of elongated, complementary guides are proximate to and extend along the axial length of the drum. The guides are sized and spaced to allow a workpiece to span the guides and roll upon them. A driver is mounted alongside the guides for rolling the workpiece on them. These guides are positioned between the drive means and the drum. The workpiece is positionable between the driver and the guides to protrude beyond the guides and reach the drum.

Abstract: The invention is concerned with performing grinding operations on a workpiece at predetermined locations along its length and is described in connection with a machine for sharpening broaches in which a broach to be sharpened is mounted on a fixed bed, the positions of all the teeth on the broach are sensed by a probe during a first or forward pass of a work head along the whole length of the broach, the information so obtained is fed to a micro-processor and the broach teeth are sharpened in turn by a grinding wheel during a return pass of the work head along the broach using the information obtained by the sensing probe and input data fed initially into the micro-processor by means of a keyboard on a control panel.

Abstract: The disclosure relates to a profile forming apparatus and in particular a cam grinding machine in which a cam to be ground is mounted for rotation about the axis of the cam shaft in a work-table and a drive motor rotates the cam about its axis at a speed controlled by a predetermined programme. The work-table is mounted for rocking movement about an axis parallel to the cam shaft axis to move towards and away from the rotating grinding wheel which grinds cam surfaces spaced apart along the camshaft. The work-table is driven positively about its axis by a reversible drive motor in accordance with a further programme to rock the camshaft towards and away from the axis of the grinding wheel as the camshaft rotates and thereby determine the shape and dimensions of the profile to which the cam is ground.

Abstract: A control system for a workpiece conditioner grinder that compensates for bowing or curvature of the workpiece. The curvature of the workpiece is initially determined by recording a set of grinding wheel position measurements when the grinding wheel is contacting the upper surface of the workpiece. These measurements are used to calculate offsets from a fixed plane of reference, and the offsets are summed with vertical grinding wheel position command signals generated while the grinding wheel is grinding the sides of the workpiece. The vertical position of the grinding wheel is thus modified by the offset in order to cause the grinding wheel to remove material in a longitudinally extending strip having a curvature conforming to the curvature of the workpiece. Alternatively, the offset signal may be generated in real time and summed with the vertical position command signal.

Abstract: A rotor assembly comprised of a multiplicity of blades mounted around the periphery of a disk has the blade tips ground to great diametrical precision when the assembly is rotated at a high speed in excess of 1000 rpm in a special grinding process. Individual blade lengths are dynamically measured while the assembly is being ground. These measurements are used to control the grinding process and to also permit accurate assessment of the quality of assemblies in general. A laser triangulation measurement system is used. It is capable of very fast reading of blade length since 3300 or more blades may pass by the measuring point each second.

Abstract: A hand-held sanding device holds a sheet of sandpaper or other abrasive sheet material around the three intersecting faces of a resilient, generally triangularly shaped block. While two of the block faces are flat right-angled surfaces the third face is a generally curved surface extending between the two flat surfaces. An angled receiving slot laterally extends along and bisects the block's curved surface, and serves to hold the ends of the sandpaper wrapped around the block in such a manner that sanding pressure placed on any surface of the block will cause the receiving slot to tighten its grip on the sandpaper ends. The block is fabricated of deformable polystyrene, has corners with three different angles and sanding surfaces of different sizes, including a curved sanding surface, and is easily gripped to handle a variety of different sanding jobs.

Abstract: A ridge element for corrugated roofs is made as a monolithic tile member (2) having an upper arched shell portion (4), the underside of which is provided with protrusions (8) showing exterior edges (10) profiled so as to be engageable with the corrugations of the opposed roofing elements (12) when these form a specific ridgeangle with each other. The same or similar ridge elements will be advantageously usable for other ridge angles, too, because a relative tilting of the roofing elements will produce small gaps only between the surface thereof and the non-engaged portions of the tile edges (10), whereby a complete sealing will require relatively small amounts of sealing compound. In practice, therefore, one type of ridge tile will be usable for all relevant ridge angles, Preferably the tile edges are provided with compressible sealing strips which will normally obviate any additional use of sealing compound, whereby the tiles are very easy to mount.

Abstract: A method of constructing a house comprising constructing modular structures for a first level of the house away from the building site in a factory. The modular structures are constructed according to Uniform Building Code standards and provide substantially all standard dimension portions of the first level of the house. The modular structures are positioned on the foundation, and the non-standard portions of the first level of the house, and the second level if there is one, are then constructed to provide those portions of the house possessing creative architectural design. Finally, a roof structure is constructed over the house and exterior finishing is performed.

Abstract: A modular greenhouse has Y-shaped vertical support members connected to roof supports and horizontal supports forming a frame for sealingly adhering glass panes thereto. The roof supports extend from a central annular ring member which has a controllable vent member which can be moved between an open and close position at the center of the roof. In addition, two adjacent vertical supports can mount a standard storm door for entrance into the greenhouse. The modular greenhouse can be adjoined to other modular greenhouse sections sharing two common vertical supports. An entranceway formed between the two common vertical supports provides passage between the two modular sections.

Abstract: A method and apparatus for making swimming pools wherein all the pool walls are formed from sheet metal panels joined together at welded junctions. The method and apparatus is characterized by constructing the bottom wall of the pool from a plurality of bottom wall panels provided with edge flange configurations that mate with edge flanges on adjacent panels and thereby facilitate alignment of the panels during assembly. The mating edge flanges of the panels are further adapted to locate the top surfaces of the panels in co-planar relationship to provide a flush pool bottom. In addition, the edge flanges of the panels are adapted to form weld receiving grooves that result in non protruding welded junctions between the panels.

Abstract: A fire rated component wall system includes first and second compartmentalized units joined by top and bottom steel cover plates. The first and second units are constructed from interlocking steel panels with sheets of fire retardant material defining a compartment therebetween. The first and second units are mated along the sides formed from the fire retardant material to provide a structural wall system with exterior steel panels and interior layers of fire retardant material. The steel panels are interlocked by an insert member from the end of one panel received and held within a slot of a second panel. An interior weld may be applied to the inside of the interlocking panels of the first and second units to provide a tamperproof connection between the steel panels.

Abstract: A joist-like wood beam formed of parallel, spaced apart, wood chords joined together by end and central elongated wood filler strips which fill the space between the chords at the opposite ends of and at the central portion of the chords. Sheet metal web units formed of angled struts are located between the central and end strips for spanning the space between and for interconnecting the chords between the strips. The chords and strips are joined together by staple-like mechanical fasteners embedded within the face of adjacent edge portions thereof. The fasteners are angled, relative to the chords, upwardly at an acute angle toward their nearest beam end so as to be placed in tension under beam loading thereby tightening the chords and strips together.

Abstract: A building construction comprised of front and rear planar supports having purlins spanning between the supports and attached to the supports by hangers attached to the outside surfaces of the supports, i.e. the surface of the support opposite the surface generally adjacent to the purlin. The hanger comprises a seat to which each purlin is connected, and two arms integrally secured to the seat. The arms include integrally formed nails which attach to the surface opposite the surface adjacent to the seat portion of the hanger. Notches are included at the periphery of the support through which the arms of the hangers are hung. The method of construction involves setting up a floor, attaching and bracing the planar supports, hanging and attaching the purlins, taking away the braces, and adding the roof, sidewalls, and the other parts to provide a building construction to be used as a storage hut or the like.

Abstract: An apparatus for sealing cover attachments to the plastics couplers of multipacks of containers, comprising conveyor means for transporting a succession of the multipacks along a generally horizontal path, a reservoir for a plurality of the blanks, an applicator device operating in timed relation to the conveyor means to place blanks for the cover attachments individually upon the multipacks moving along the conveyor means so that tabs, which extend out from the plain portion of each blank, are disposed laterally in relation to the conveyor path and, along each side of the conveyor path, heating means for directing hot gas onto the tabs and onto the lateral surfaces of the coupler so as to render them heat-sealable together. The apparatus further comprises folding means for folding the tabs downwardly and pressure means for holding the tabs against the coupler to heat-seal the coupler and cover attachment together.

Abstract: In a film wrapping machine for wrapping packages in stretchable film, a monitoring system is provided to generate a signal each time film is drawn into the machine. If no film is drawn into the machine indicating that the film source has expired, broken or otherwise become disengaged from the film feeding apparatus for the wrapping machine, the machine is stopped. The film draw into the machine is monitored by an electrical switch which is coupled to a tensioning roller, the motion of which is adjusted to activate the switch each time even at least a minimum length of film is drawn into the machine.

Abstract: In a stretch film wrapping machine an improved control system provides for automatic or manual selection of one of at least two differing width film rolls and provides individualized wrapping parameters dependent upon the film width selected. Automatic film selection is performed in response to signals identifying the height, width and length of a package to be wrapped which characteristics are sensed or measured by a package sensing system. Both automatic and manual film selection includes timing controls for synchronizing film gripping and clamping apparatus with underfolding apparatus dependent upon the film selected to provide improved control over the tensioning of film wrapped about individual packages.

Abstract: An improved apparatus for collecting and stacking insulation batts or other similar articles and transferring these collections into one of a plurality of packing or compression chambers. The apparatus has a batt-transfer device that operates in a horizontal reciprocating motion, moving a first collection of batts from a collecting surface to a position in a packing chamber located on either side of the collection surface, and cycling back for another collection. Lifting members in each chamber raise the stack up to a predetermined height and holding fingers are inserted underneath this collection to hold them in place. The lifting members then cycle back down to the floor or bottom of the chamber for successive loads with the holding fingers being alternately extended and retracted in sequence to retain the successively larger collection of batts.

Abstract: A method of sealing a cryogenic tube comprising the steps of inserting the tube into a tubular body made from a heat-shrinkable material and having a length greater than that of the receptacle, heating the tubular body to a temperature sufficiently high to effect shrinkage of the tubular body and compressing the ends of the tubular body to cause the opposite tube walls to melt together to form an envelope completely surrounding the receptacle.

Abstract: A vertical form, fill and seal packaging machine in which a predetermined length of web or film is pulled downwardly past a tube forming collar by endless belts located downstream of the collar. A power-rotated feed roll is located upstream of the collar and pulls film from a supply roll for delivery to the collar, the feed roll being driven at a higher surface speed than the pull down belts. To match the supply of the feed roll with the demand of the belts, means sense the tension in the film at a location between the feed roll and the forming collar and cause the feed roll to slip relative to the film as an inverse function of that tension.

Abstract: A riding spur is disclosed wherein the spur body is provided with a shank extending rearwardly therefrom. The shank terminates in a bifurcated rowel support member that is secured to the shank by a pin. A rowel is rotatably mounted in the bifurcated portion and the rowel and bifurcated support are rotatably mounted on the pin extending into the shank of the spur. The rowel thus rotates about a first axis while the rowel support rotates about an axis perpendicular to the rowel axis.

Abstract: An apparatus primarily adapted for removing cranberries from vines in a flooded bog bed includes a self-propelled, wheeled chassis and at least a pair of forwardly mounted, transversely extending reel assemblies. Each reel assembly includes a support frame having a base portion and a pair of arms. A reel is rotatably supported on the arms of the support frame. The reel includes an elongated shaft and a plurality of spaced discs interconnected by rods. A trunnion drive motor is secured to one of the arms and is directly coupled to the shaft to rotate the reel during harvesting operations. The base portion of the frame is pivotally secured to a spindle support arm at a free end thereof. The opposite end of the spindle support arm is pivoted to the wheeled chassis. The reels may pivot about an axis transverse to the base portion of the frame and move vertically to conform to the bog bed.

Abstract: The present invention provides an improved cotton duct structure for a cotton harvester. The air supply line has a nozzle which releases air on the cotton ducts ascending front wall, thereby projecting harvested cotton in a direction towards the receptacle on the cotton harvesting machine.

Abstract: A vacuum operated fruit harvesting machine is disclosed for harvesting fruit from fruit trees. The fruit harvesting machine of the invention comprises a picker head connected to an airflow control valve. A discharge valve is then connected to the airflow control valve by means of a plurality of rigid or flexible conduits. The picker head comprises a curved conduit having a lower lip portion. A gripper means is positioned relative to the upper edge of the curved conduit for gripping the stem of the fruit to be picked. As the fruit is conducted into the picker head, the fruit pivots against the upper edge of the curved conduit causing the stem to be peeled away from the fruit at the calex thereof. The airflow control valve comprises a pair of gates which open in response to a pressure differential between the atmospheric air and the air contained within the picker head.

Abstract: The passage of material through a textile spinning or twisting machine is regulated through operation of a control element associated with the movement of said material. Light reflected from the moving material is converted into a variable electrical signal which is then modulated and used to operate a light-emitter. The modulated output of the light-emitter is sensed by a receiver located remote therefrom, but in direct-line-of sight, into an electrical command signal for operating the control element.

Abstract: A wire rope for use in a traction type elevator system is coated with a soft-solid agent or a greasy agent having a drip temperature higher than 55.degree. C. and exhibiting physical properties such that it is evaporated in an amount less than 1 weight percent at 105.degree. C. for an interval of eight hours and elevates the coefficient of friction or traction between the wire rope and the drive sheave when coated on the wire rope.

Abstract: In order to wind a newly joined thread onto a tube newly inserted on a spooling device on an open-end spinning mechanism, the newly joined thread, together with a thread portion containing a leader, is guided away before the start of the bobbin build-up. Thereupon, the thread portion containing the leader is severed from the thread, and subsequently, the thread supplied by the open-end spinning mechanism is transferred to the newly inserted tube. To exchange a full bobbin for a new tube, a thread break is produced, the open-end spinning mechanism is cleaned and the thread is thereupon joined anew. To carry out this process, there are, on an open-end spinning mechanism, provided with a thread-joining device and a spooling device, a thread-suction device (4), a thread feeder (42) transferring the thread (35) supplied to the thread-suction device (4) to a newly inserted tube, and a thread-severing device (41) assigned to the thread-suction device (4).

Abstract: Disclosed is an improved device to control and regulate the opening and closing of a cross section of a turbojet propulsive nozzle having at least one hydraulic cylinder acting on at least one movable flap element. The invention includes a first system to supply the cylinder with hydraulic fluid under pressure for normal operation and a second supply system to be used in an emergency. The elements for changing from the normal operation to an emergency operation are combined with the elements to generate in the hydraulic cylinder a differential pressure, such that the cross section of the nozzle assumes an intermediate position assuring sufficient thrust for the engine, while avoiding the danger of overloading the compressor. The system is effected automatically when the pilot actuates the emergency supply system.

Abstract: A catalytic converter includes a longitudinally disposed body portion having first and second shell halves and an interior through which the combustion product can flow. A manifold is provided for forming a passageway between the body interior containing a reducing catalyst and the body interior containing an oxidizing catalyst. The manifold includes first and second manifold halves, with each manifold half including a pair of flanges which extend perimetrally and substantially completely along the interior wall of one shell half. The manifold flanges are disposed substantially parallel to the interior wall and coupled thereto. The manifold flanges include a portion which is recessed inwardly from the interior wall and first and second mating sections. The recessed portions include air holes for introducing air into the passageway between the reducing catalyst and the oxidizing catalyst.

Abstract: A pump jack of the type comprising a rocker arm pivotably mounted intermediate its ends on a support member, said rocker arm being divided by said pivot mounting into a sucker-rod limb and a drive limb wherein the improvement comprises a pneumatic motor pivotably attached to the drive support member and further pivotably attached to the mounting base of the pump jack to provide the power to reciprocate the pump jack. The working fluid of said pneumatic motor being natural gas which is available from the well casing of the well without any interference with the flow of the oil in the oil tube of the well thereby making use of an energy source available at any oil well without having to provide gasoline to drive a rotating type gasoline engine or electricity to drive an electric motor usually of the rotating variety.

Abstract: In a refrigeration system such as a split Stirling system, fluid seals associated with the reciprocating displacer are virtually dragless clearance seals. Movement of the displacer relative to the pressure variations in the working volume of gas is retarded by a discrete braking element. Because it is not necessary that the brake providing any sealing action, the brake can be designed for greater durability and less dependence on ambient and operating temperatures. Similarly, the clearance seal can be formed of elements having low thermal expansion such that the seal is not temperature dependent. In the primary embodiments the braking element is a split friction brake.