Saw accessory for aerial work platform

A wall saw accessory is provided for an aerial work platform, where a wall saw is movably affixed on a track secured to a wall to be sawed. The accessory includes a saw/track manipulator fixable to the aerial work platform. The saw/track manipulator movably supports the track and saw and enables positioning of the saw and track to and from a working position. A hydraulic power source is coupled with a water supply to provide hydraulic power and coolant flow to the wall saw. In one arrangement, the accessory additionally incorporates an onboard pressure washer, which serves to streamline the process and maintain a clean work area. The accessory may be attached to a lift vehicle including a chassis supporting an onboard water supply.

BACKGROUND OF THE INVENTION

The present invention relates generally to aerial work platforms and, more particularly, to a wall saw accessory cooperable with an aerial work platform to facilitate a wall sawing operation.

It may be desirable in the building construction industry to cut openings in exterior walls and the like, including those made of concrete, stone, and other hard materials. Such cuts are best made using a saw mounted to a carriage for movement along a track attached to the wall. The carriage is typically guided along the track by a plurality of rollers or other guide elements bearing against contact surfaces on opposite sides of the track.

In order to mount the saw for a cutting operation, several operations are typically required in order to secure the track to the wall and mount the saw on the track. This operation is particularly troublesome when a cut is to be performed in an exterior wall at a significant height.

Additionally, in order to maintain the integrity of the saw blade during the saw operation, the wall saw typically requires a source of coolant such as water to be applied to the saw blade during use. Accessibility to the coolant source can be an obstacle to efficient operation.

Still further, the cutting operation can leave a residue on the cut surface, which ultimately requires cleaning via a pressure washer or the like. Particularly at height, a pressure washer may be burdensome to manipulate, and, like the coolant for the wall saw, the fluid source for the pressure washer can create additional problems.

BRIEF SUMMARY OF THE INVENTION

In order to overcome these drawbacks of existing wall saw systems, the present invention provides a wall saw accessory for an aerial work platform that facilitates manipulation of the saw and track while streamlining the saw operation. Additionally, the wall saw accessory of the present invention enables a single operator to perform the wall sawing operation more efficiently than an entire crew using conventional arrangements.

In an exemplary embodiment of the invention, a wall saw accessory for an aerial work platform is cooperable with a wall saw is movably affixed on a track secured to a wall to be sawed. The wall saw accessory includes a saw/track manipulator fixable to the aerial work platform, where the saw/track manipulator movably supports the track and saw and enables positioning of the saw and track to and from a working position. Hydraulic power from the machine's hydraulic system may be coupled with a water supply to provide hydraulic power and coolant flow to the wall saw. Alternatively, a separate hydraulic power source may be mounted on the aerial work platform.

Preferably, the saw/track manipulator includes a bottom bracket securable to the aerial work platform and supporting a lateral rail; a sliding bracket movably mounted on the lateral rail; a telescope assembly secured to the sliding bracket, where the telescope assembly includes a hydraulically assisted lifting arm; and a rotatable track support assembly attached to the lifting arm of the telescope assembly via at least one structural link. The track support assembly includes holding brackets for holding the track during installation and removal.

The saw/track manipulator is preferably constructed to enable positioning of the saw and track with five degrees of freedom. Moreover, the hydraulic power source may be coupleable with the saw via a quick-connect coupler.

The wall saw accessory may additionally include a pressure washer system connected with the hydraulic power source. In this context, the pressure washer system may comprise a spray nozzle, a hose, and a pressure adjustment mechanism. Moreover, the hydraulic power source may further include a toggle switch for the wall saw and the pressure washer system such that only one is operable at a time.

In another exemplary embodiment of the invention, a lift vehicle includes an aerial work platform, and the wall saw accessory of the invention coupled to the aerial work platform. The vehicle may include a chassis, wherein the water supply is at least one water tank mounted to the chassis, and preferably two water tanks saddle mounted on the chassis.

In still another exemplary embodiment of the invention, a method of constructing a lift vehicle with wall saw accessory includes the steps of movably affixing a wall saw on a track; securing the wall saw accessory to an aerial work platform by fixing a saw/track manipulator to the aerial work platform, the saw/track manipulator movably supporting the track and saw and enabling positioning of the saw and track to and from a working position; and coupling a hydraulic power source with a water supply, the hydraulic power source providing hydraulic power and coolant flow to the wall saw.

Other exemplary embodiments of the invention include a coolant circuit integrated with the aerial work platform and a pressure washer system utilizing the coolant circuit.

DETAILED DESCRIPTION OF THE INVENTION

An aerial work platform provides a convenient way for an operator to work at heights. Typically, a platform includes a floor upon which the operator can stand and a guard rail about its perimeter. Tools and other functional apparatus may be integrated with the guard rail or floor to facilitate use by the operator. The platform itself is raised and lowered by a suitable lifting apparatus, such as a boom lift or scissors lift or the like. Typically, a position of the vehicle as well as its platform can be controlled by the operator from the platform.

FIG. 1is an exemplary perspective view of an aerial work platform10. The platform10includes a floor or base12and a guard rail14about its perimeter. A control unit16is integrated with the guard rail14.

With continued reference toFIG. 1and with reference toFIG. 2, the wall saw accessory of the present invention generally includes a saw/track manipulator20attachable to the aerial work platform10. As will be described in more detail below, the saw/track manipulator20movably supports a track and wall saw and enables positioning of the saw and track to and from a working position. The accessory additionally includes a hydraulic power source22shown schematically inFIG. 1either diverted from the machine's hydraulic pump, which normally powers the drive system, or as a separate unit mounted on the aerial work platform10. The hydraulic power source22is coupled with a water supply and provides hydraulic power and coolant flow to the wall saw.

The saw/track manipulator20is a multiple degree of freedom (preferably five-degree of freedom) mechanical device that aids in the positioning of both the saw and track section simultaneously. The manipulator includes a bottom bracket24(FIG. 1) secured to the aerial work platform10and supporting a lateral rail26(FIG. 2). A sliding bracket28may be movably mounted on the lateral rail26for side-to-side movement across the lateral rail26. Alternatively, the bracket28may be fixed. A telescope assembly30is secured to the sliding bracket28and includes a hydraulically assisted lifting arm32. A rotatable track support assembly34is attached to the lifting arm32of the telescope assembly30via at least one structural link36. The track support assembly34includes holding brackets38for holding the track during installation and removal.

With this assembly, the manipulator is constructed to enable positioning of the saw and track with preferably five degrees of freedom, including hydraulically assisted vertical movement (preferably, +/−four inches) with manual adjustment in and out, left and right, and lockable 360° rotation of the saw and track via the track support assembly34. A fifth joint via the structural link36provides for angular and horizontal adjustment of the track to the wall. A simple tether-mounted pendant or other suitable structure controls the vertical cylinder motion. Once positioned, the track is secured to the wall in a conventional manner and disconnected from the manipulator20for the sawing process. The manipulator20may be provided with a stow cradle to prevent it from interfering with the sawing process.

The hydraulic power source22may itself form part of an accessory assembly providing multiple energy power sources for air or water powered tools. In one arrangement, the power sources may be powered either from an onboard engine driven generator or from an outside AC power outlet. With reference toFIG. 3, the hydraulic power source is preferably coupleable with the wall saw via a known quick-connect coupler40or the like. The quick-connect coupler is preferably provided with an emergency disconnect feature, where the coupling is disconnected when the operator attempts to move the machine while it is connected to the saw mounted on the wall. The power source22preferably provides hydraulic power to the wall saw and incorporates an onboard water source (described below) required for wall sawing and pressure washing. In one arrangement, the hydraulic power consists of a maximum of 25 GPM at 2500 psi. This flow is provided by the machine function pump and is adjustable by the user at the accessory control box from a minimum of 10 GPM up to the maximum flow. The cooling water for the saw is also used to cool the returning hydraulic oil before it returns to its tank.

This power arrangement allows for the saw operator to be independent on the site by not tethering the mobile unit to fixed hydraulic and water supplies. The chance of hose damage due to construction site traffic is also significantly reduced or eliminated because all hoses from source to user are managed on the machine.

FIG. 4illustrates a pressure washer system42also connectable to the hydraulic power source22. The pressure washer system42includes a hydraulically driven high pressure water pump, a conventional spray nozzle, a hose, and a pressure adjustment mechanism44. As shown inFIG. 6, the hydraulic source22further includes a toggle switch46for the wall saw and the pressure washer system such that only one is operable at a time. A combination of the water pump coupled with the source of hydraulic power22and a water supply may serve generally as a coolant circuit providing coolant flow to any aerial work platform accessory.

The onboard pressure washer42is a hydraulically driven unit that provides preferably 4 GPM at a user-selected operating pressure of between approximately 1000 psi and a maximum of 3500 psi. The pressure washer42is mounted on the platform where the operator can easily adjust the washing pressure on the fly. Activation of the pressure washer is achieved via a simple two-step process. Once the saw is turned off, the manual water diverter valve47is turned to the pressure washer selection, and the power switch for the pressure washer is turned on. See, for example, steps1and3inFIG. 6(discussed in detail below).

FIG. 5illustrates the chassis50of a lift vehicle incorporating the wall saw accessory according to the present invention. As shown inFIG. 5, the onboard water source for the wall saw accessory preferably includes two “saddle” mounted water tanks52on the chassis50. In a preferred arrangement, the water tanks52are 150 gallon water tanks. Water is pumped from the tanks52to the platform at a constant flow rate, preferably about 4 GPM.

In operation, the saw is first connected to generally the midpoint of the desired track length, the saw and track themselves may be of conventional construction. This subassembly is then secured to the manipulator20via the holding brackets38before ascending the platform12to the cut location. The operator then lays out the first cut and mounts and levels conventional track brackets to the wall. Position controls on the aerial work platform are then used to position the saw/track assembly in the necessary orientation adjacent the mounted brackets. Final adjustments are accomplished using the manipulator20via its five degrees of freedom to finally align the track with the track brackets secured to the wall. Locking bolts are then installed to secure the track to the bracket.

Subsequently, the operator disconnects the manipulator from the track, and the manipulator20is returned to its stowed position. The track/bracket connection bolts can then be fully secured for the sawing operation. Resultant binding, due to the weight transfer from the machine to the wall, may require slight vertical adjustments via the telescope assembly30to more easily accomplish the separation.

The operator then installs the appropriate blade and guard for the saw, makes the required power and water connections, and positions the platform at a safe working distance from the saw. With reference toFIG. 6, the water supply diverter valve is placed in the water hose position, and the water pump switch is activated. With water flowing to the blade, the saw power switch is then activated, and the desired hydraulic flow rate is selected. The sawing operation then proceeds until the cut is finished.

Upon completion of the first cut, the operator reverses the start-up procedure: the hydraulic power is switched off, the water pump is turned off, and the saw guard and blade are removed. The manipulator20is then reattached to the saw and track, and the track/bracket bolts are removed. The operator can then prepare for the next cut in the same manner as the first, moving the saw/track assembly to the next cut location. The wall and equipment can be power washed using the onboard power washer at any time the saw is not being operated.

With the hydraulic power source, the manipulator and the pressure washer of the wall saw accessory according to the invention, overall operating costs for sawing operations can be reduced. The system provides time savings, reduced or eliminated back charges, improved quality, reduced worker turnover, reduced maintenance costs, and the ability to almost double the output of a two-man sawing crew. The time savings begin with the reduced set up time at the start of the job and continue throughout the working day from the conveniences of the accessory functionality. Steady productivity throughout a work day results from the lessened operator strain while using the manipulator. Traditionally, the operator would have to handle the up to 10-foot section of track and the 100+ pound saw individually and for each cutting sequence. With the saw accessory including the saw/track manipulator, once the saw and track are installed at the beginning of a work day, the operator is not required to lift the saw again until the end of the day when it is stowed for transport.

The integrated pressure washer allows for the operator to maintain a clean working area and tools, also saving time by not forcing the crew to wait until the slurry has dried before attempting to remove it from the wall and at the same time eliminating possible back charges from doing so. Quality is improved in both the short and long terms from the use of the manipulator in the positioning of the cumbersome saw and track. Work days will not require as much effort, which will add up to equal more experienced saw operators. The per man productivity can also increase by essentially turning a two-man operation into one easily managed by a single person. Furthermore, maintenance costs will also be reduced by the ability to rent readily equipped machines from local rental facilities.