Abstract: The invention is directed to a cartridge bin and a rotatable drum. The objective is to reduce labor associated with loading and unloading articles processed in a rotatable drum, for instance during laundering operations. The cartridge bin is configured to at least partially nest within the rotatable drum. Features are disclosed to rotationally align and couple these two components.

Abstract: The present invention relates to a drum drive for a truck mixer with a vehicle drive train and a mixing drum, wherein the drum drive can be driven by at least one electric motor.

Abstract: A system for managing a concrete delivery vehicle having a mixing drum 14 and hydraulic drive 16 for rotating the mixing drum, including a rotational sensor 20 configured to sense a rotational speed of the mixing drum, a hydraulic sensor 22 coupled to the hydraulic drive and configured to sense a hydraulic pressure required to turn the mixing drum, a temperature sensor for sensing temperature of the drum, and a communications port 26 configured to communicate a slump calculation to a status system 28 commonly used in the concrete industry, wherein the sensing of the rotational speed of the mixing drum is used to qualify a calculation of current slump based on the hydraulic pressure required to turn the mixing drum. Temperature readings are further used to qualify or evaluate a load. Also, water purge connections facilitate cold weather operation.

Abstract: A system for calculating and reporting slump in a delivery vehicle having a mixing drum 14 and hydraulic drive 16 for rotating the mixing drum, including a rotational sensor 20 configured to sense a rotational speed of the mixing drum, a hydraulic sensor 22 coupled to the hydraulic drive and configured to sense a hydraulic pressure required to turn the mixing drum, and a communications port 26 configured to communicate a slump calculation to a status system 28 commonly used in the concrete industry, wherein the sensing of the rotational speed of the mixing drum is used to qualify a calculation of current slump based on the hydraulic pressure required to turn the mixing drum.

Abstract: The present invention relates to a building material mixer having a mixer drum which can be rotationally driven by a mixer drive, with the mixer drum being rotatably supported by the mixer drive at a mixer frame part, in particular a traveling gear frame part, at one of its end face ends and with the mixer drive having a drive part, in particular a hydraulic motor, and a drive transmission connected to the mixer drum. In accordance with the invention, the building material mixer is characterized in that the mixer drive is movably supported by movable bearing means at the mixer frame part allowing tilting movements; and in that the mixer drum is fastened to the transmission housing of the drive transmission.

Abstract: A mixer drum driving apparatus includes a mixer drum carried on a frame of a mixer truck in a frontward tilted condition to be free to rotate, and a drive source configured to drive the mixer drum to rotate. The drive source includes a motor which is disposed in a space between a rear portion of the mixer drum and a rear portion of the frame in order to drive the mixer drum to rotate.

Abstract: A warm mix asphalt plant comprising a counter-flow drum, apparatus for precisely metering flows of A/C and water, an asphalt expander with no moving internal parts where a circular curtain of flowing clean water is mixed with a coaxial circular curtain of moving heated A/C to create asphalt foam which is heated and mixed inside a lower portion of the asphalt expander and then distributed to cover aggregate inside the counter-flow drum.

Abstract: A concrete mixing-and-transport truck is provided, which comprises a stirring cylinder with a rotary sealed feeding/discharging opening. A annularity sealed cavity is formed between the outer wall of a rotary inner cylinder (15), the inner wall of a fixed outer cylinder (6-2), the back end face of a rotary flange support base (6-1) and the front end face of a sealing end cover (7). At least one sealing belt (13) is set in the annularity rotary sealed cavity. The back end face of the last end sealing belt (13) is contacted tightly with the front end face of the sealing end cover (7). The stirring cylinder and the feeding/discharging opening are connected rotationally by reliable rotary sealing so as to make the stirring cylinder keep rotating when feeding, and reduce the centre of gravity of the carrier vehicle. The truck improves driving safety, eliminates concrete demixing problem and improves the quality of concrete and architecture quality.

Abstract: A system for monitoring plant equipment is provided. Another aspect provides an automated analysis system wherein software instructions operably compare sensor data to predefined valves and determine mechanical problems in multiple machines. In another aspect, a cement manufacturing system includes sensors for sensing movement conditions of cement making machines. A further aspect provides a central computer connected to vibration sensors associated with cement making machines, where software instructions perform real-time comparisons and machine performance determinations, based at least in part on sensed signals.

Abstract: A concrete mixer truck includes: a driving device that drives a mixer drum to rotate; a pressure sensor that detects a pressure of the working fluid in the driving device; a material introduction determination unit that determines whether or not a material for generating the mixed concrete has been introduced into the mixer drum; a pressure determination unit that determines whether or not the pressure of the working fluid detected by the pressure sensor has fallen to a set pressure set in advance in accordance with a carrying amount and a fluidity of the mixed concrete after the introduction of the materials for the mixed concrete into the mixer drum; and a notification device that notifies an operator that the pressure of the working fluid in the driving device has fallen to the set pressure on the basis of the determination made by the pressure determination unit.

Abstract: The invention relates to a method for adjusting concrete rheology requiring only that load size and target rheology value be selected initially rather than requiring inputs into and consultation of a lookup table of parameters such as water and hydration levels, mix components, temperature, humidity, aggregate components, and others. Dosage of particular rheology-modifying agent or combination of rheology-modifying agents is calculated based on a percentage of a nominal dose calculated with reference to a nominal dose response (“NDR”) curve or profile. The NDR profile is based on a correlation between a rheology value (e.g., slump, slump flow, yield stress) and the rheology-modifying agent(s) dose required to change rheology value by one unit (e.g., slump change from 2 to 3 inches) such that exemplary methods can employ corrective dosing based on the NDR and the measured deviation by the system.

Abstract: A silicone composition comprising an organopolysiloxane containing at least two silicon-bonded alkenyl and/or hydroxyl groups in the molecule and a filler having a BET surface area of at least 10 m2/g is prepared by kneading the components in a batchwise high-shear mixer. The mixer includes a rotatable mixing pan (1), a high-speed rotation agitator (3) disposed eccentrically in the pan, and a stationary scraper (4) disposed in the pan for creating a vertical counterflow.

Abstract: Recycled asphalt product is heated within an indirectly heated recycled asphalt product heater by passing heated gases through heat exchange members within a drum while the recycled asphalt product is moved through the drum from one end to the other end of the drum. The heat exchange members provide conduits for the heated gases, the conduits extending from an inlet adjacent a source of heated gases to an outlet communicating with an exhaust, each conduit following a looped path and having two or more segments each with a longitudinal length extending from adjacent one end of the drum to adjacent the other end of the drum. The segments are arranged serially in a serpentine configuration, are generally parallel to one another, and are spaced apart radially within the interior of the drum.

Abstract: A concrete agitating drum (1) is driven by a hydraulic motor (81). A connection switch-over valve (20) is arranged to have a function to regulate a flow cross-sectional area of pressurized working oil supplied to the hydraulic motor (81) from a variable capacity hydraulic pump (10). The variable capacity hydraulic pump (10) is driven by a combustion engine (60) together with a charge pump (11). When a discharge pressure of the charge pump (11) is low, the connection switch-over valve (20) maintains a small flow cross-sectional area to rotate the agitating drum (1) at a low rotation speed so that fuel consumption of the combustion engine (60) is suppressed to be small. When the discharge pressure of the charge pump (11) becomes high, the connection switch-over valve (20) enlarges the flow cross-sectional area, thereby realizing a rated rotation speed of the agitating drum (1).

Abstract: A system for recovering concrete wash product includes a support frame mounted pivotally to a chassis of a transit concrete mixing vehicle, and a container mounted to the frame for arcuate movement with the frame, between a collecting position with the container disposed below a discharge chute of the vehicle, and a dispensing position with the container disposed adjacent an opening of a mixing drum of the vehicle. The container initially is placed in the collecting position to receive concrete wash product from the discharge chute by gravity as the chute is cleaned with water. After cleaning, the frame is pivoted to raise the container to the dispensing position, and a valve is opened to allow the concrete wash product to flow from the container into the mixing drum by gravity. In vehicles equipped with booster axle systems, the booster axle frame supports and positions the container, and also supports and positions the booster wheel/axle assembly.

Abstract: A rotary concrete mixing drum (16) for a vehicle (10) having a drivetrain (18) for rotating the drum (16) includes a wall (33) having an opening (67) and a hatch cover assembly (37/200) removably closing the opening. The hatch assembly (200) may include a hatch cover (202) coupled to a panel (204) by bolts (212).

Abstract: A power take-off unit is connected to a power take-off gear/port on a concrete mixing truck transmission, the power take-off unit being driven by the engine so it is always providing power as long as the engine is running. A hydraulic pump is connected to and driven by the power take-off unit. Hydraulic lines connect the pump to a planetary drive assembly for the concrete mixing drum; the drum itself is capable of receiving only a small/light load of concrete, in the range of two to five cubic yards.

Abstract: A self-purging auxiliary fluid supply system for supplying washout or makeup water or other fluids under pressure to a truck-mounted concrete mixing/dispensing drum is disclosed. The system includes a truck-mounted fluid reservoir for containing a quantity of fluid connected to supply fluid to an air-operated diaphragm pump connected to supply auxiliary fluid from the fluid reservoir under pressure to a discharge assembly. The pump further provides an integral purge system for displacing fluid in the fluid supply system after use.

Abstract: A composite, heavy duty rotary concrete mixing drum (16) for coupling to a vehicle having a drivetrain (18) for rotating the drum (16) comprises a wall and a drive ring. The wall defines a first end of the drum and a second end of the drum. The drive ring (39) is coupled to the first end of the drum and includes a hub (108, 252) and a plurality of extensions (110, 254). The hub is operatively coupled to the drivetrain. The plurality of extensions (110, 254) extend outwardly from the hub (108, 252) into the wall of the drum. At least one of the extensions includes an aperture (121, 126) extending therethrough. Rotation of the hub by the second drivetrain causes rotation of the drum.

Abstract: A rotary concrete mixing drum (16) includes an interior surface (74) at least partially provided by a polymer (90) impregnated with a slip agent.

Abstract: An environmental shield for reducing or eliminating leakage of materials from transit vehicles, including truck-mounted concrete mixers, is provided. The environmental shield preferably engages at least a portion of an opening on a mixer drum such that the leakage that generally occurs in such situations as travel along hilly or bumpy terrain, surging, etc. may be prevented or minimized. The environmental shield preferably includes a discharge cover and a combination steel/rubber abrasion resistant sealing member and may be preferably coupled to a charging hopper of the transit vehicle.

Abstract: A heavy duty rotary concrete mixing drum capable of attachment to a vehicle. The drum comprises a first end which engages a vehicle powered drive assembly which rotates the drum for mixing of said concrete and a second end from which mixed concrete is discharged. The drum is manufactured from at least one layer of plastics material; wherein the drum includes a wall having integral internal formations which promote mixing and discharge of said concrete and an inner surface which promotes mixing of the concrete.

Abstract: A computer controlled pumping and measuring system is used to dispense chemicals into a concrete mix. The redundant use of positive displacement pumps and flow meters ensure that any problems with the chemical dispensing are immediately caught. The computerized control system may be operable to control exact batch configurations of concrete and aggregate in conjunction with the chemical dispensing, as well as provide precise mixture control and recording of the various components.

Abstract: An automated apparatus for preparing material samples includes a rotatable drum support assembly, a drum rotatably contacting the drum support assembly, a fan, and a powered drive mechanism. The drum includes a hollow main section and first and second hollow end sections attached to the main section. The first hollow end section includes a first end wall tapering to a first outer aperture. The second hollow end section includes a second end wall tapering to a second outer aperture. The fan is mounted approximate to the first outer aperture for establishing forced air flow through the drum toward the second outer aperture. The drive mechanism rotatably communicates with the drum support assembly for rotating the drum. The apparatus is useful for preparing samples such as paving materials for test such as the determination of specific gravity and absorption.

Abstract: A target object modification apparatus includes an aligner device configured to be able to manipulate the posture of a supplied target modification minute object (8), a first feed unit configured to be able to individually supply a target modification minute object (2) to the aligner device, and an injection unit configured to be able to inject modifiers onto the target modification minute object after the target modification minute object is set to a predetermined posture by the aligner device.

Abstract: An apparatus and method for testing asphalt in the field is described. The apparatus includes a motor for rotatively driving a chamber containing the asphalt to be tested. The chamber is rotated while cooler, ambient air is circulated through the asphalt particulate. After cooling the particles of the asphalt, the asphalt particles are separated by tumbling action.

Abstract: A power assisted method and injector device for controllably delivering to patients a dispersion medicament or diagnostically active agent, the homogeneity of which is preserved throughout delivery. Diagnostically active agents disclosed are gas microbubble suspensions useful in ultrasonic diagnostic imaging and liposomal formulations in which liposome vesicles are loaded with iodinated compounds.

Abstract: A cementing apparatus includes a readily transportable chassis, such as that of a convention cement truck or a trailer, a rotatable mixer, a holding tank for receiving material extruded from the mixer, a pump that receives and pressurizes material from the holding tank, and an outflow conduit for directing the pressurized material to a desired location. The cementing apparatus may also include a fluid inflow system for pressurizing and directing fluid from an external source into the mixer. In addition, a valve may be positioned at an appropriate location to shut off the flow of material from the mixer through the outflow conduit and to cause fluid from an external source to flow through the outflow conduit. The apparatus may be used to mix and pump cement slurry into a drill hole through an outflow conduit and to pump displacement fluid into the drill hole through the same outflow conduit.

Abstract: There is disclosed a barrel mixer (11) comprising a support (12) for a rotary mixer barrel (13), including a tipping arrangement (14) for said barrel (13) limiting tipping between a mixing position in which the barrel (13) is angled so as to retain its contents and a tipping position in which the barrel (13) is angled so that its contents are poured out, a motor (15) and transmission (16) mounted on said support (12) for rotating the barrel including step-down gearing between the motor (15) and the barrel (13), the motor (15) and gearing (33) tipping with the barrel (13), the motor shaft (15b) being, at an intermediate position between mixing and tipping positions of the barrel (13), vertical, and the motor (15) being of a type having a mounting plate (31) surrounding the motor shaft (15b).

Abstract: A power assisted method and injector device for controllably delivering to patients a dispersion medicament or diagnostically active agent, the homogeneity of which is preserved throughout delivery. Diagnostically active agents disclosed are gas microbubble suspensions useful in ultrasonic diagnostic imaging and liposomal formulations in which liposome vesicles are loaded with iodinated compounds.

Abstract: Over-the-road concrete mixer motor trucks with rotatable concrete mixer drums have indicia placed on the drums comprising advertisements of a product or service, and which may be readable from opposite sides of the motor truck as it traverses a roadway. In alternate embodiments, indicia on the rotatable mixer drum is placed in a helical or spiral fashion or simulates the appearance of an article other than the drum itself.

Abstract: A drying and mixing plant is provided comprising a tapered inner drum (1) and an oppositely tapered outer drum (4) attached together concentrically and rotated as a unit. A burner (37) directs a hot air stream into the small end (2) of the inner drum (1). Material is fed into the small end of the inner drum, where impellers (40) lift it and drop it into the hot air stream and move the material through the inner drum (1) aided by the downward taper of the inner drum. The material exits the inner drum and enters the outer drum (4) where an additive material is introduced and mixed with the material (42) as both move through the chamber (28) between the inner and outer drums to a material outlet. The receiving end (5) of the outer drum (4) is enclosed in a shroud (12), therefore the air stream is directed through the chamber (28) between the drums, the chamber having an expanding cross section which slows the air down allowing fines to precipitate out.

Abstract: A barrel mixer assembly is disclosed. The barrel mixer assembly comprises a rotary mixer barrel and a support for a rotary mixer barrel. The support includes a tipping arrangement for the barrel, wherein the support limits tipping of the barrel between a mixing position in which the barrel is angled so as to retain its contents and a tipping position in which the barrel is angled so that its contents are poured out. The support further includes wheels disposed proximate a bottom portion of the support. The assembly has a motor having a motor output shaft aligned parallel to an axis of rotation of the barrel. The assembly also has a transmission mounted on the support for rotating the barrel. The transmission includes step-down gearing between the motor and the barrel. The motor and gearing tip with the barrel when the support is moved between the mixing position and the pouring position.

Abstract: A drum insulating device for a concrete truck for insulating ready mix concrete trucks. The drum insulating device for a concrete truck includes a sheet of material having a pair of outer layers and an inner layer and further having a first portion and a second portion and being adapted to be securely fastened about a mixing drum of a concrete truck with fasteners; and also includes fastening members for fastening the first and second portions together.

Abstract: A barrel mixer and assembly is disclosed. The barrel mixer comprises a rotary mixer barrel and a support for the rotary mixer barrel. The support includes a tipping arrangement for the barrel, wherein the support limits tipping of the barrel between a mixing position in which the barrel is angled to retain its contents, and a pouring position in which the barrel is angled so that its contents are poured out. The mixer also a motor having a motor output shaft aligned parallel to an axis of rotation of the barrel, and a mounting plate attached to the motor and surrounding the motor output shaft. Finally, the mixer has a transmission mounted on the support for rotating the barrel. The transmission includes step-down gearing between the motor and the barrel.

Abstract: A front discharge concrete vehicle includes a chassis having a front end and a rear end, a mixing drum supported by the chassis having a first end and a second end, a support column extending between the chassis and the second end of the drum to support the second end of the drum and a cab enclosure supported by the chassis below the second end of the drum. The cab enclosure includes an integrally formed housing extending about a first operator station and a second operator station. The cab enclosure further includes at least one control member between the first and second operator stations and an opening extending between the first and second operator stations. The opening extends below the at least one control member to enable the at least one control member to be accessed from both the first operator station and the second operator station.

Abstract: A front-end discharge concrete mixer truck which includes a truck chassis with frame rails wherein the frame rails are spaced apart a distance greater than 34 inches. The truck chassis having a front end and a rear end. An engine is mounted to the truck chassis midway between the front end and the rear end thereof. A mixer assembly is attached to the chassis. The mixer assembly has a rotatable barrel and an outlet chute. The mixer barrel is driven by the engine. The outlet chute is movable so as to discharge concrete at the front end of the chassis.

Abstract: A washout bucket which receives waste water and concrete material washed from equipment used to deliver concrete material from the mixing drum of a cement mixer truck to a desired location on a job site, is used in cooperation with a tag axle assembly pivotally mounted on a rear end of the truck to recover the concrete material washed from the equipment. The washout bucket can be connected to the tag axle assembly. The tag axle assembly is then raised to an upright position and in the process the front of the washout bucket contacts the mixing drum and tips over, emptying the waste material into the mixing drum. As a result, waste concrete material can be properly disposed of or salvaged for reuse rather than indiscriminately washed onto the ground at the job site.

Abstract: Pieces of meat are tumbled with a marinade in a tumbler that has a smoothly continuous surrounding side wall with no protrusions or baffles or other protrusions contacting the pieces of meat. The tumbler is rotated about the axis of the side wall and gas is pumped from the tumbler during the tumbling to maintain a reduced pressure. The gas may be pumped to maintain a lower reduced pressure for a first time interval and to permit a higher pressure, still below atmospheric pressure, for a second period of time during a rest period. These two pressure levels are alternated during the alternate tumbling and rest periods.

Abstract: A tobacco treatment system comprising a rotatable cylinder and a plurality of axially directed flights, with each flight having a forward side and a back side relative to the rotational motion of the cylinder, with both the forward and back sides being concave-open in a direction toward the interior of the cylinder.

Abstract: A mixing apparatus, comprising, a frame, a pair of handles secured to the frame with each handle having a proximal and a distal end thereto and a pair of downwardly depending support elements. A first wheel is secured to the distal ends of the pair of handles by frame elements and a rear set of wheels are secured to the proximal ends of the pair of handles by frame elements. A mounting element is secured to the frame for supporting a drive engine. A drive chain mechanism is linked to a toothed wheel and to the drive engine, the toothed wheel having an internal brake drum and internal brake shoes. The internal brake drum and internal brake shoes are connected to a brake cable having a tension reduction cam for tension reduction. A centrifugal clutch for engagement with the drive mechanism is linked to a throttle operably engaged to the to the drive engine.

Abstract: A portable concrete plant that can be transported on a single vehicle to a construction site consists of a transporting vehicle, a rotating drum for mixing the concrete, containers for sand and crushed rock, a scale for weighing a mixture of sand and crushed rock, a conveyor for conveying the mixture of sand and crushed rock to the rotating drum, a container for portland cement, a conveyor for conveying the portland cement to the rotating drum, a source of water, and a concrete pump for dispensing the concrete from the rotating drum. A fly ash container and a second scale for weighing fly ash may also be on the vehicle. The entire apparatus may be controlled by a computer which controls the various containers and scales so as to vary the proportions of sand, crushed rock, fly ash, portland cement, and water in the rotating drum to produce concrete of varying strength. The entire apparatus has dimensions which meet the length, width and height requirements for vehicles moving on the highways.

Abstract: A concrete mixing truck having an apparatus for mixing materials used to make concrete includes a mixing product receiving and delivery assembly, a platform, which is located proximate the mixing product receiving and delivery assembly for providing operator access thereto, and a repositionable safety rail. The safety rail is located on and partially encloses the platform and is positionable, via a hinge or other suitable means, between an upraised position and a lowered position. With the safety rail in the upraised position, an operator present on the platform is provided with an added measure of safety to prevent against accidental falling and resulting injury. With the safety rail in a lowered position, the platform is essentially inaccessible to operators and the mixing product receiving and delivery assembly is unobscured and completely accessible to machinery such as associated with a ready-mix concrete plant.

Abstract: In an apparatus for heating and mixing a particulate material composition, an elongated drum is supported for rotation on a frame and hot gases are supplied to the drum at an output end of the drum and directed toward an input end. An outer shell encircles the drum adjacent the output end and defines an outer mixing chamber between the drum and the shell. A first particulate material is introduced into the drum adjacent the input end, is conveyed toward the output end, and is diverted into the mixing chamber. A second particulate material is introduced into the outer mixing chamber and is heated to an output temperature during mixing with the first material. Thereafter, the mixed materials are delivered from the outer mixing chamber and from the apparatus.

Abstract: An apparatus is provided for uniformly coating particulate material. The apparatus includes a frame, a cylindrical drum rotatable about an axis tilted with respect to a horizontal plane, and a spray nozzle extending into the drum so as to spray a coating solution onto the particulate material tumbled within the rotating drum. Perforations in the side wall of the drum allow a flow of air through the drum so as to dry the material within the drum as it is coated with solution. A vacuum system removes the coated seeds from the drum without manual handling. In operation, the seeds form a dense mass, and migrate away from the mass as the seeds increase in size and weight from the sprayed coating. Eventually, all of the particles are uniformly coated, and thus a new mass is formed and the process repeated until the material reaches a desired size.

Abstract: A system and method for reclaiming unused portions of mixed concrete by adding a chemical agent to retard the hydration state of the concrete for up to several days. When the stored concrete is again desired for use, a chemical accelerating agent is added to the mixed concrete which returns the hydration state to normal, once again allowing the concrete to set. The concrete can then be poured at a construction site or alternatively, the stored concrete can be added to a new batch of newly mixed concrete before pouring.

Abstract: A granulating and coating apparatus comprising a rotary drum to be charged therein a powdery or granular material, and a baffle plate provided in the rotary drum and not rotatable together with the rotary drum. The rotary drum is formed to be a polygonal shape. This polygonal shape may be, for example, a pentagon, a hexagon, an octagon or a decagon. The baffle plate may be positionally fixedly supported. Or, the baffle plate can be made to change a position in a rocking direction, a position of the rotary drum in the axial direction, a depth of insertion into a layer of a powdery or granular material or an angle of insertion by use of plurality of actuators.

Abstract: A concrete mixing vehicle having a retractable tag axle assembly and a distribution chute is disclosed. To ensure that the tag axle assembly does not come into contact with the distribution chute as the tag axle assembly as it moves between a first ground engaging position and a second elevated position, a limit switch is provided in the control circuit for the tag axle assembly. The limit switch only permits movement of the tag axle assembly when the distribution chute is outside of the tag axle assembly's path of travel as it moves between said first and second positions.

Abstract: The invention includes apparatus and method for inhibiting the hardening of a wetted concrete premix in a filled concrete mixer including providing a rotatable concrete mixer drum having a plurality of sealed apertures located throughout the entire length and circumference of the drum such that at least one of the apertures is located at or near the bottom of the drum at all points of rotation, and injecting a fluid under pressure through at least one aperture and into the drum when filled with a charge of wetted concrete premix to disperse the fluid throughout a portion of the charge adjacent to the aperture and up to the surface of the charge thereby inhibiting hardening.

Abstract: An auxiliary tag axle assembly for a work vehicle such as a ready-mix concrete truck which is positionable via actuation of a linear actuator to extend the wheel assembly from the rear end of the vehicle's frame to a ground engaging disposition and retractable to a stowed position where the wheels straddle the rear end of the frame and with the auxiliary axle elevated to a position above the level of the bottom of the frame. The need for plural actuators is obviated by utilizing a flexible cable of a predetermined length to effect desired movement of the working parts upon extension and retraction of the main linear actuator.