Patent Application
20120325505
The present disclosure relates generally to a coupler, and more particularly, to a coupler including at least one visibility window.
Typically implements are coupled to mining and construction machines, such as wheel loaders, hydraulic excavators, skid steer loaders, multi-terrain loaders, track loaders, backhoe loaders, etc., to perform work. One example of such an implement is a pallet fork. A pallet fork may be mounted to one of these machines for performing work, such as picking up and carrying palletized materials around a building site or at a factory. Other non-limiting examples of implements include buckets, hammers, blades, brooms, and snow plows.
When a particular implement is attached to the machine, it enables the machine to perform a variety of tasks. Different implements may be attached to enable the machine to perform different tasks. The ability to attach multiple implements to a machine so the machine can perform a variety of tasks, which is called “multitasking,” increases the utility and value of the machine for the owner. On the other hand, attaching and detaching implements to a machine may be cumbersome and time consuming. The time spent switching implements instead of working reduces the utility of the machine.
Some implements may be mounted to a machine with a simple pin-style joint, which does not facilitate the switching of implements. To create the pin-style joint, a pin is manually inserted into complementary bores in the machine and implement. Switching implements with this pin-style joint requires an operator or technician, or multiple technicians, to manually remove the pins that hold the first implement to the machine, remove the first implement, position a second implement on the machine, and manually reinsert the pins. Besides being time consuming, this switching operation may require considerable skill on the part of the operator and technicians.
A coupler solves many of the problems that pin-style joints present for switching implements. The coupler provides an alternative way to mount implements to mining and construction machines. The coupler is interposed at the junction between the machine and the implement. The implement is attached to the coupler, and the coupler is attached to the machine. When switching implements, the operator of the machine may operate the coupler from inside the machine's cab to release a first implement. The machine is then repositioned near a second implement, where the operator may then manipulate the coupler and the machine to pick up the second implement.
One example of a coupler is described in U.S. Pat. No. 7,814,689 (the '689 patent) issued to Vering et al. The '689 patent describes a coupler for connecting a pallet fork to a machine. The coupler includes a mounting structure for mounting the coupler to the machine and a mounting structure for mounting the coupler to an instrument, such as a bucket or pallet fork. The mounting structure for mounting the coupler to the implement includes wedges that are received in wedge pockets in the implement.
Although the coupler of the '689 patent may be able to connect an implement to the machine, the coupler may not provide sufficient visibility to allow the operator of the machine to see, for example, the tines of the pallet fork from the cab of the machine. As a result, the coupler may prevent the operator from being able to see tines of the pallet fork when attempting to position the pallet fork, e.g., to pick up palletized materials.
The disclosed system is directed to overcoming one or more of the problems set forth above.
In one aspect, the present disclosure is directed to a coupler for connecting an implement to a machine. The coupler includes a first mounting structure configured to attach the coupler to the implement. The first mounting structure includes a first actuator including a first cylinder rod extendable relative to a first cylinder body, and the first cylinder rod has a first rod longitudinal axis. The first mounting structure also includes a first wedge attached to the first cylinder rod, and the first wedge is movable between a retracted position and an extended position by the first actuator. The first wedge includes a first wedge tip insertable into the implement, and the first wedge tip has a first wedge longitudinal axis. The first rod longitudinal axis is offset from the first wedge longitudinal axis to form a first opening extending through the coupler adjacent the first actuator. The coupler also includes a second mounting structure configured to attach the coupler to the machine.
In another aspect, the present disclosure is directed to a coupler for coupling a first body to a second body. The coupler includes a frame including a first mounting structure configured to attach the coupler to the first body and a second mounting structure configured to attach the coupler to the second body. The first mounting structure includes a first actuator including a first cylinder rod extendable relative to a first cylinder body, and the first cylinder rod has a first rod longitudinal axis. The first mounting structure also includes a first wedge attached to the first cylinder rod, and the first wedge is movable between a retracted position and an extended position by the first actuator. The first wedge includes a first wedge tip insertable into the first body, and the first wedge tip has a first wedge longitudinal axis. The first rod longitudinal axis is offset from the first wedge longitudinal axis to form a first opening extending through the coupler adjacent the first actuator. The first opening extends between the frame and the first actuator above the first wedge, and the first wedge longitudinal axis extends towards the first opening.
In a further aspect, the present disclosure is directed to a method of coupling an implement to a machine. The method includes attaching a coupler to the machine and attaching the implement to the coupler by actuating a first actuator including a first cylinder rod extendable relative to a first cylinder body. The first cylinder rod has a first rod longitudinal axis, and a first wedge is attached to the first cylinder rod. The first wedge is movable between a retracted position and an extended position when the first actuator is actuated. The implement is also attached to the coupler by advancing a first wedge tip of the first wedge into a first wedge pocket in the implement when the first actuator is actuated to position the first wedge in the extended position. The first wedge tip has a first wedge longitudinal axis, and the first rod longitudinal axis is offset from the first wedge longitudinal axis. The method also includes providing a first opening extending through the coupler and adjacent the first actuator to allow an operator operating the machine in a cab of the machine to see through the first opening to at least a portion of the implement.
Reference will now be made in detail to exemplary embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
In an exemplary embodiment, the machine 10 may be a wheel loader, and the implement may be a pallet fork 30, as shown in
The coupler 50 may include a frame 52 that may include a mounting structure (described in detail below) for attaching the coupler 50 to various implements, such as the pallet fork 30, and a mounting structure (described in detail below) for attaching the coupler 50 to the machine 10. The frame 52 provides rigidity between the mounting structures, and transfers forces between the machine 10 and the connected implement. The structure of the frame 52 may vary depending on the type of machine 10, the type of implement(s) intended to be coupled with the coupler 50, etc.
The frame 52 may include one or more plate-shaped center members 54, one or more plate-shaped middle members 56, and one or more plate-shaped end members 58. In the embodiment shown in
According to an exemplary embodiment, the mounting structure for mounting the different implements, such as the pallet fork 30, to the coupler 50 may include an elongated member, such as a tube 68, of the frame 52 that extends between the middle members 56 and is also attached to the center members 54.
The mounting structure for attaching the coupler 50 to various implements may also include one or more actuators, such as hydraulic cylinders 70, mounted at one end to the frame 52. In the exemplary embodiment, the coupler 50 includes two hydraulic cylinders 70. As is known in the art, each hydraulic cylinder 70 includes a cylinder rod 72 that is movable with respect to a cylinder body 74 mounted to the frame 52 under power of pressurized hydraulic fluid. Alternatively, instead of being hydraulically actuated, other actuators may be provided, such as pneumatic or other similarly actuated cylinders. Each hydraulic cylinder 70 is operable to extend the cylinder rod 72 from, and retract the cylinder rod 72 into, the cylinder body 74. The cylinder rod 72 may move with respect to the cylinder body 74 along a linear path of movement that is generally parallel to a longitudinal axis 76 of the cylinder rod 72. In the exemplary embodiment, the longitudinal axis 76 of the cylinder rod 72 is generally parallel to and collinear with the longitudinal axis of the cylinder body 74.
The cylinder bodies 74 of the hydraulic cylinders 70 may be mounted to the frame 52 by respective connecting members 78. In the exemplary embodiment, the connecting members 78 include one portion connecting to the tube 68 and another portion connecting to the respective middle members 56. Alternatively, the connecting members 78 may include only the portions connecting to the tube 68, or only the portions connecting to the respective middle members 56. As another alternative, the connecting members 78 may be omitted and the hydraulic cylinders 70 may connect directly to the tube 68 or the respective middle members 56.
Wedges 80 are connected to the ends of the respective cylinder rods 72 (opposite the ends extending into the cylinder bodies 74). The hydraulic cylinders 70 are configured to extend and retract the wedges 80. The extension and retraction of the wedges 80 occurs during the mounting and dismounting of the implement (e.g., the pallet fork 30) to the coupler 50. Although two hydraulic cylinders 70 are illustrated, a single hydraulic cylinder 70 with a linkage system may be used to extend and retract both wedges 80. For example, the operator in the cab 16 may initiate, with a single input via an input device (not shown), e.g., in the cab 16, actuation of both hydraulic cylinders 70. In an embodiment, the various components of the coupler 50, e.g., the center member 54, middle member 56, end member 58, hydraulic cylinder 70, and wedge 80, on one side of the centerline 51 may be substantially a mirror image of the same components on the other side of the centerline 51, as shown in
As shown in
The tip portion 84 may be positioned with respect to the attached cylinder rod 72 such that the longitudinal axis 86 of the tip portion 84 is offset from the longitudinal axis 76 of the attached cylinder rod 72 towards the outboard side of the coupler 50 (e.g., outward from the centerline 51 of the coupler 50), as shown in
Since the offset between the longitudinal axes 76, 86 allows the hydraulic cylinders 70 to be positioned closer to the centerline 51 of the coupler 50, an opening or window 90 of visibility may be formed that extends through the coupler 50 at two locations. The longitudinal axes 86 of the wedge tip portions 84 may extend towards the respective windows 90, as shown in
When attaching the pallet fork 30 to the coupler 50 after the coupler 50 is attached to the lift arms 22 of the machine 10, first the pallet fork 30 may be positioned with respect to the coupler 50 so that the tube 68 may be positioned in the hooks 36, as shown in
The top tube 68 may include ears 69. When the coupler 50 is mounted to an implement, such as the pallet fork 30, the ears 69 may abut the hooks 36, as shown in
The wedges 80 may be retracted from the corresponding wedge pockets 34 in the pallet fork 30 so that the coupler 50 may be detached from the pallet fork 30. In the retracted positions shown in
The details of the pallet fork 30 and the coupler 50 shown in
The disclosed coupler 50 may be applicable to any machine to which an implement is mounted. Several advantages may be associated with the coupler 50. For example, the coupler 50 may be easy to use, and may allow for fast mounting to the machine 10 and/or the implement.
The coupler 50 may also provide greater visibility to the operator operating the machine 10 from the cab 16. For example, as discussed above, the operator may have the line of sight 92 through the coupler 50 to various areas on and through the implement during and after mounting of the implement. The placement of the hydraulic cylinders 70 and the shape of the wedges 80 may be adjusted to improve visibility.
For example, the windows 90 may allow the operator in the cab 16 to see through the coupler 50 to the tines 38 of the pallet fork 30, e.g., the distal ends of the tines 38, thereby enabling the operator to see when the tines 38 are positioned properly to engage or lift materials, e.g., to position the tines 38 in a pallet. For example, the operator may view one of the tines 38 through one of the windows 90 and the other one of the tines 38 through the other one of the windows 90. The amount of the offset between the longitudinal axes 76, 86 described above (and therefore the size of the windows 90) may depend on various factors, such as size of the pallet fork 30 (e.g., the space between the tines 38, the length of the tines 38, etc.), the distance between the pallet fork 30 and the cab 16, a desired area of the pallet fork 30 or other implement to view, the forces and/or bending loads acting on the wedges 80 when actuated, etc. As a result, providing one or more of the windows 90 gives the operator increased confidence and increases the efficiency of the operation, e.g., the handling and transport of palletized and/or non-palletized materials.
Various types of implements may be used interchangeably with the coupler 50. The implements may include the windows 90 of visibility described above and/or other implements without the windows 90. The distance between the wedge tip portions 84 of the coupler 50 (or the distance between the longitudinal axes 86 of the tip portions 84) may be determined based on a set distance between the wedge pockets 34 in the interchangeable implements that are intended to be mounted to the coupler 50. The set distance may be generally constant between implements having the windows 90 of visibility and without the windows 90. Thus, the coupler 50 includes the windows 90 that allow for increased visibility for the operator while remaining useable with other various types of implements, such as buckets and other types of implements for which the operator may not necessarily desire to have increased visibility. As a result, since various types of implements may be used with the disclosed coupler 50, the design may be versatile and less costly to manufacture and use.
It will be apparent to those skilled in the art that various modifications and variations can be made to the coupler. Other embodiments will be apparent to those skilled in the art from consideration of the specification and practice of the disclosed coupler. It is intended that the specification and examples be considered as exemplary only, with a true scope being indicated by the following claims and their equivalents.
