Patent Application
20100201181
The present invention relates to machines for removal of floor surface coverings and particularly to an improved arrangement of hydraulics and transport wheel on such machines.
Some prior floor surface machines use hydraulics to adjust the height and angle of a blade situated on the front of the machine. Two such machines are shown in U.S. Pat. No. 5,641,206 to David B. Craft and U.S. Pat. No. 5,772,284 to Stephen B. Lindsey and Randy D. Lindsey. In each case, a hydraulic cylinder operates a blade holder that is adjustably mounted on the front of the machine, and the hydraulic cylinder attaches to the top of the blade holder. Craft and Lindsey are typical in that the hydraulic cylinder is mounted on top of the blade holding mechanism in a conspicuous manner such that the hydraulic ram and seals are exposed. Removal of floor covering materials creates a great amount of debris that often causes damage to the components of the floor covering removal machine. In particular, on many such machines the hydraulic cylinder or other hydraulic components for operation of a blade are exposed to the ongoing debris created. This causes scarring of the hydraulic ram and gouging out of dust and pressure seals in the bottom end of the hydraulic cylinder's barrel. The problems are exacerbated by the design of the double action hydraulic cylinder barrels normally having two threaded ports for attachment of hydraulic hoses to pressurize the cylinder barrel for extension and for retraction. The debris gradually causes much damage to the hydraulics system and results in loss of use of the machine and the expense of repair. With a top mounted hydraulic cylinder, designers must be careful to make the barrel static to prevent rubbing and abrasion of hoses from surrounding structures and debris.
On a floor surface removal machine, the need for changing the blade angle using the blade holder comes from the degree of difficulty of material being removed from the floor and the wear of the original blade angle by the blade moving across floor substrate, which is usually abrasive concrete. A need exists for a new and novel approach to changing the angle of a blade on a floor surface removal machine. Such approach should avoid damage by debris to the hydraulics involved and should provide a compact streamlined design. In the present invention, a hydraulic system for operation of a blade holder is arranged beneath the blade holder and beneath other features of the machine body. The blade holder and machine body shield and protect the hydraulic elements from damage through debris such as vinyl flooring, carpet, dirt, broken pieces of wood, and especially sharp broken pieces of ceramic type flooring material. The hydraulic system adjusts the angle of the blade through manipulation of the blade holder upward and downward. To further enhance the ability of the cylinder to maintain the blade angle, side plates are provided for the blade holder to mechanically fix the blade position when removing extremely well bonded floor coverings and or coatings such as ceramic or hardwood floors.
The invention provides for attachment of the hydraulic cylinder controlling the blade holder in a specific beneficial and operable arrangement. The horizontal angle of the hydraulic cylinder with relation to the machine frame and the blade holder is determined to provide optimal performance. The hydraulic cylinder is pivotally mounted to the blade holder and the machine body by a bracket and pin at each point. The attachment points of the hydraulic cylinder are in accordance with the preferred range of the horizontal angle of the hydraulic cylinder.
It is noted that the blade holder is pivotally attached by a pivot shaft to the front of the machine body. In the present invention, the relationship between the pin attaching the hydraulic cylinder ram to the bottom of the blade holder and the pivot shaft of the blade holder is specified. The relationship between these pivot points of the hydraulic ram and the blade holder effects the preferred operation of the hydraulic system for manipulation of the blade holder.
In one embodiment, the invention may use two separate low-pressure hydraulic systems to actuate the hydraulic cylinder for manipulation of the blade holder. In using two separate hydraulic systems, each system provides a separate hydraulic pump and each pump is an infinitely variable bidirectional axial piston pump. Using separate pumps allows the operator a choice of either pump desired for this modification.
However, a second efficient and sometime preferable embodiment requires only one hydraulic system for operation of the blade holder using the hydraulic cylinder arrangement of the invention. In this case, the port hydraulic pump is equipped with an integral auxiliary hydraulic pump. A selector valve of electric solenoid switch means allows hydraulic fluid to flow to hydraulically change the angle of blade in relation to the floor. A check valve block maintains hydraulic cylinder pressure while the machine is in operation. The solenoids (one for up, one for down) are controlled by a two pole double throw switch which provides 12 volt DC power to the solenoids. Power can be 12 volt DC or any other on board available power source (220 volt AC, 48 volt DC etc.). The cylinder's hydraulic power is supplied by the auxiliary hydraulic pump and controlled by the described solenoid directional control valve and electrical control switch system.
This modification also produces another valuable function. The need for any other lifting mechanism to attach to a front transport wheel is alleviated, whether manual or electric. This unique hydraulic design for manipulating the blade holder allows the blade holder to continue upward beyond the horizontal axis of the machine to a point that allows insertion of a transport wheel. After insertion of a transport wheel, reversal of a throw switch brings the blade holder with the transport wheel attached back down into a transport position.
Referring now to the drawings,
In an operating position, the blade tool 18 contacts and penetrates the floor covering being removed by bearing sufficient weight for the blade to operate on the covering. Floor surface removal machines are known to provide a jack placed on the front of the machine for providing a transport position when the apparatus is not in use. Some machines have provided permanently attached wheels beneath the front of the machine and a hydraulic cylinder attached to the top of the blade holder to lift the blade holder off the floor surface. In this arrangement, lifting the blade holder causes the front end of the machine to lower down onto the wheels. Lowering the blade holder causes the blade tool to address the floor surface at the angle desired. As discussed in the background, this methodology exposes the hydraulics on the front of the machine to damage. It is also known that the small wheels that are permanently attached have drawbacks due to their size, position and permanent attachment. Large transport wheels have been attached previously by using a jack to lift the front of the machine. However, this is inefficient.
The present apparatus overcomes the problems with transport wheels and blade holder adjustment by providing an improved hydraulic arrangement for manipulation of the blade holder 16. The main body section includes an upper frame section in the upper portion of the main body and a lower frame section beneath the upper frame section and encompassing the bottom area of the main body section. As an initial feature of the improved hydraulic arrangement, a hydraulic cylinder 22 is arranged within the lower frame section in the bottom area of the floor surface removal machine 10. This hydraulic cylinder with hydraulic ram 24 operates the blade holder that is pivotally attached to the front end 12 of the machine. Incorporating the hydraulic cylinder within the lower frame section streamlines the apparatus and protects the hydraulic cylinder and related parts from damage. The present invention overcomes problems found in attempting to locate the hydraulic cylinder within the bottom area such as the providing sufficient power to the blade holder for proper lifting, lowering and adjustment of the blade tool.
As shown in the embodiment of
The front bracket 36 is attached to the blade holder 16 and provides a cam-like motion for operation of the blade holder with the hydraulic cylinder 22. The connection of the front pin to the front bracket and blade holder is situated below the height of the connection of rear pin to the rear bracket within the lower frame section. The ram 24 is attached to the front bracket by a front pin 38 that permits pivoting of the ram within the front bracket.
A transport wheel 40 may be attached to the blade holder by inserting a transport wheel support member 42 into a blade holder clamp 44 as shown in
A preferred arrangement of the hydraulic system is shown in
Several features of the invention include that a finite adjustable blade angle is achieved by the hydraulic circuit's fitting size and flow control valves as described in the hydraulic schematic. Further, the size and angle of the front bracket 36, acting as a cam, is designed specifically to produce the most power at different stages of the blade holder 16 angle changes. The front bracket is designed to place the most power at the angle were the front detachable transport wheel 40 makes contact with the floor. The front bracket could be moved to other positions to give more power to any position of the blade holder angle if needed. The length of the angle travel can also be impacted by the placement and angle of the front bracket. Thus, for successful operation of the blade holder, if the front bracket is positioned to have too much travel of the front pin pivot point, this detracts from the power points on the angles desired, such as when the front transport wheel touches the floor. There is a direct link to the size and shape of the arm of the front bracket to the length of the blade holder. If the blade holder is one length, the front bracket has to compliment the size and length of the blade holder. If the size and shape of the front bracket is not matched with the length and travel of the blade holder, the mechanism will not produce enough power at the critical power points on the blade holder to lift the machine. A preferred design is shown in the drawings, and as illustrated the blade holder and attachments for the blade operating hydraulics are compactly arranged within the lower frame section of the main body section of the apparatus.
The point where the cylinder rear end 32 is attached to the rear bracket 26 on the frame of the machine also effects power as the blade holder 16 angle changes. The rear bracket impacts the angle of the hydraulic cylinder 22 at which it connects to the front bracket 36. If the front bracket and the angle of the hydraulic cylinder are not designed to the produce the most power at the very precise points in the power curve, the machine will not have the power to lift the machine 10. Preferably, the blade holder shaft 54 (i.e. the pivot point of the blade holder) and the front pin 38 of the hydraulic ram 24 in the front bracket will align whereby the front pin is directly below the blade holder shaft when the transport wheel 40 is attached and first touches the floor surface when the blade holder 16 is lowered. In other words, the angle of the front bracket should cause the pivot point of the front pin to be below the pivot point of the shaft when the transport wheel touches.
The front bracket's cam arm length and position, the length and position of the rear bracket for the cylinder creates the angle of the cylinder. The angle of the cylinder and the length of the blade holder are designed in the preferred embodiment to complement each other and provide needed power and streamlined operation. If any one of these components is not appropriate, then the speed, power and travel of the blade holder could cause the mechanism to have any of the following issues: the blade holder to travel at to slow or fast rate of change, the blade holder not lift high enough to insert the front wheel or not have the power at the critical power points in the angle change to operate or lift the machine.
In the preferred embodiment several angles of components with respect to the blade holder are considered. These angles are from the high point where attached to the rear bracket to the low point where attached to the front bracket. First, with respect to the angle of the cylinder, when the blade holder is at the highest point the cylinder is at 9 degrees. When the blade is lowered to the pivot point where the most power is needed, the angle is 5 degrees, and when the blade is lowered to the lowest position, the cylinder is at 4 degrees.
Second, with respect to the angle of the blade to the horizontal plane of the machine, when the blade is raised to the highest point the blade is at a downward angle of 2 degrees. When the blade is at the pivot point where the front transport wheel makes contact with the floor surface, the blade is at a 10 degree downward angle, and when the blade is lowered to the lowest point the angle is 45 degrees.
These angles discussed are subject to a range of plus or minor a few degrees possibly in which the blade holder may be successfully operated and various tolerances may be determined. However, the present tolerances were found through experimentation to be preferable and to overcome problems with the compact arrangement of hydraulics and the provision of power needed.
The present application claims benefit of U.S. Provisional Patent Application no. 61/148,638 filed Jan. 30, 2009.
| Number | Date | Country | |
|---|---|---|---|
| 61148638 | Jan 2009 | US |
