Patent Application
20100115802
The present invention is directed to an earth-working vehicle, such as a backhoe loader, having an implement, such as a backhoe, in which the implement is capable of being shifted transversely of the vehicle.
For many years, it has been common to mount the backhoe support structure or swing tower on a frame and utilize a pair of hydraulic cylinders to pivot the tower with respect to the frame. In such a unit, the hydraulic cylinders are usually connected to the boom support or swing tower on opposite sides of the vertical pivot axis between the swing tower and the frame. For example, in one type disclosed in Long U.S. Pat. No. 3,047,171, the free ends of the piston rods of the hydraulic cylinders are connected to the frame structure at spaced locations while the cylinder barrels are connected at transversely spaced points to the swing tower or mast.
In more recent years, an earth-working vehicle of the type disclosed in the Long patent has also been mounted in a manner that the entire unit can be shifted transversely with respect to the vehicle. The frame supporting the mast or tower is supported on transversely extending rails that are secured to the rear end of the vehicle. This allows the operator to position the frame in any one of an infinite number of positions with respect to the fixed rails and readily lock the unit with respect to the rails.
A side-shift backhoe incorporates a frame which supports the backhoe mechanism and which is mounted for lateral, transverse movement with respect to the tractor or the like on which the backhoe is mounted. This type of backhoe was developed primarily for trenching in confined spaces, such as in close proximity to a house or other obstruction and enables operation closer to the obstructions than if the backhoe were mounted centrally of the rear of the tractor.
Traditionally, an implement bucket has been repositioned by uncontrolled movement of the backhoe while supporting the backhoe bucket teeth on the ground to one side and pushing the slide carrying the backhoe out on the other side using hydraulic cylinders. Some of the side-shift backhoes required complex components including hydraulically or manually operated clamps or pins.
In one preferred embodiment, an earth-working vehicle, such as a backhoe loader, has an elongated main frame and an implement support slidingly mounted to the main frame. The implement support is mounted at one end of the main frame and is capable of sliding transversely with respect to the elongated main frame. The vehicle also includes a motive means to slide the implement support with respect to the elongated main frame. The motive means includes a hydraulic motor mounted to one of the main frame and the implement support and either a chain having both ends secured to the other of the main frame and the implement support or the rack of a rack and pinion secured to the other of the main frame and the implement support. The hydraulic motor has a driving sprocket to drive the chain or a pinion to drive the rack and slide the implement support.
Other features and advantages of the present invention will be apparent from the following more detailed description of the preferred embodiment, taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the invention.
Upper and lower plates 22 and 24 each have a pair of transversely spaced abutments 27 secured thereto by bolts and the abutments engage the forward surfaces of plates 18 while the lower surface of upper plate 22 is supported on the edge of upper plate 18. Thus, the entire tower frame 20 may be laterally shifted with respect to rails 16 and locked in adjusted positions by lock means 28.
Mobile tower frame 20 supports a swing tower 40 that has a substantial C-shaped configuration with upper and lower portions 42 and 44 respectively pivotally supported on upper and lower plates 22 and 24 by pivot pins 46. Pivot pins 46 define a vertical tower pivot axis for supporting swing tower 40 for pivotal movement on tower frame 20. Swing tower 40 supports an implement, such as backhoe 48 for pivotal movement about a horizontal pivot 49. The backhoe 48 is well known in the art.
The swing tower 40 is pivoted with respect to the tower frame 20 by a pair of hydraulic cylinders that are mounted in order to allow the tower frame 20 to be moved along the sliding rails 16 while still having the center of gravity for the backhoe 48 as close as possible to the rear axle for the vehicle 10. As most clearly shown in
Piston rods 54 of the hydraulic cylinders are connected to an intermediate portion of the swing tower 40. This connection consists of brackets 66 extending from the body of the swing tower 40 with pins 68 extending through the apertures in the brackets and apertures in the end of piston rods 54. As shown in
As shown in
The ends of a roller chain 79 are secured to a pair of yoke end connectors 80 that are mounted on the implement support plate 18. See
The LSHT motor 72 rotates under applied hydraulic pressure from the vehicle hydraulic circuit at very low speeds without need for an intermediate speed reducer, and directly moves the roller chain 79, which moves the backhoe 48. The mechanism is simple with very few parts. Hence, frictional losses are minimal and the system is easy to maintain. The steel roller chain 79 is designed to operate without an enclosure. Due to the short duration and extent of movement, as well as the low speed of operation, the roller chain 79 runs efficiently without lubrication.
By using the present system, movement of the backhoe 48 is controlled. Safety is improved since the controlled movement is without jerking that is prevalent in the prior systems. The present system is compact and improves vehicle maneuverability.
A second embodiment of the slidable implement support is shown in
In
The mounting bracket 73, hydraulic motor 72 and pinion 88 may be mounted on the rails 16, as shown in
While the invention has been described with reference to a number of preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.
