Patent Description:
A header typically includes conveyors to move crop materials from the lateral ends of the header towards the center of the header, and from the center of the header back towards the combine's threshing and separating system. In some cases, these conveyors comprise draper belts that are supported on rollers or the like. Draper belts typically require occasional replacement, as well as periodic maintenance to adjust tension and tracking. It is also sometimes necessary to remove crop material that become trapped between the inner surface of the belt and the support rollers. To facilitate such service, the a draper belt might be mounted on one or more movable belt tensioning rollers. For example, a tensioning roller might be located at one end of the belt, and be mounted such that it is movable towards and away from an opposite roller to increase and decrease tension. The tensioning roller is attached to the header frame by one or more compression or tension springs, which are deformed to generate tension in the belt. In some cases, the spring compression is adjusted by rotating mounting screws that hold the springs to the frame.

Such maintenance can be time-consuming, and relatively difficult to accomplish. For example, it might be necessary to move a tensioning roller mounted on M16 bolts up to two inches or more to remove the belt, thus requiring as many as <NUM> complete turns of each mounting bolt. Such procedure can become even more difficult when the belt maintenance is performed in the field to open the belts to remove accumulated crop materials.

Thus, the state of the art still requires development. <CIT> discloses a conveyor belt tensioning arrangement for an agricultural harvesting header and the agricultural harvesting header with the conveyor belt tensioning arrangement, the arrangement comprising a conveyor belt roller supported on a roller carriage, the conveyor belt roller being spring-loaded to maintain tension in the conveyor belt, the conveyor belt roller also being supported to pivot about an axis generally perpendicular to the longitudinal extent of the conveyor belt roller.

This description of the background is provided to assist with an understanding of the following explanations of exemplary embodiments, and is not an admission that any or all of this background information is necessarily prior art.

In one exemplary aspect, there is provided a draper belt tensioning system according to claim <NUM>. Preferred embodiments are provided in the dependent claims.

In another exemplary aspect, there is provided a method for disconnecting a draper belt tensioning system according to claim <NUM>.

Embodiments of inventions will now be described, strictly by way of example, with reference to the accompanying drawings, in which:.

Exemplary embodiments of the present invention provide draper belt tensioning systems for use on headers for agricultural equipment, such as combines, swathers, windrowers, and the like. It will be appreciated that other embodiments may be used in other types of machines having a similar arrangement of parts, upon incorporation of the appropriate features of the inventions herein.

<FIG> illustrates an example of a prior art agricultural combine <NUM>, with which embodiments of the invention may be used. The combine <NUM> includes a chassis <NUM> that is configured for driving on a surface (e.g., the ground or a road), such as by being supported by pneumatic wheels <NUM>, tracked wheel assemblies, or the like. The combine <NUM> includes a threshing and separating system <NUM> mounted on or within the chassis <NUM>. The threshing and separating system <NUM> may include mechanisms such as one or more threshers (e.g., an axial flow thresher), sieves, blowers, and the like, as well as an associated grain hopper and unloader. Threshing and separating systems <NUM> and their associated components are well-known in the art, and need not be described in detail herein. The combine <NUM> also may include other features, such as a spreader <NUM>, operator cab <NUM>, and the like.

Referring also to <FIG>, the combine <NUM> also includes a header <NUM>, which is configured to cut and harvest crop material from the ground as the combine <NUM> drives in the forward direction F. For example, the header <NUM> may include one or more cutter bars <NUM> located at or near the leading edge of the header <NUM> to cut crops at or near the ground level, and one or more reels <NUM> configured to pull the crop material backwards towards the header <NUM>. The header <NUM> also includes crop conveyors <NUM> that are configured to move the crop material at the lateral ends of the header <NUM> towards the center of the header <NUM>. The crop conveyors <NUM> may be in the form of draper belts, auger screws, or the like. At the center, the header <NUM> may include a feeder conveyor <NUM> that conveys the crop material backwards towards a crop outlet <NUM>. The feeder conveyor <NUM> may comprise a draper belt, a feeder drum, one or more augers, or the like. The header <NUM> also may include gauge wheels <NUM> or skids to control the height of the header <NUM> over the ground.

The header <NUM> is built on a frame <NUM>, which is attached to the chassis <NUM> by a feeder housing <NUM>. The feeder housing <NUM> is configured to convey crop material backwards from the header <NUM> to the threshing and separating system <NUM>. The feeder housing <NUM> may be movable by one or more feeder housing actuators <NUM> to raise and lower the header <NUM> in a vertical direction V relative to the ground.

The illustrated exemplary header <NUM> is a unitary header having a single frame that extends continuously between the ends of the header <NUM> in the lateral direction L. In other embodiments, the header <NUM> may comprise a multi-segment or articulated header having a center section and one of more wing sections movably attached to the lateral end of the center section by pivots or linkages. In either case, the header <NUM> has a central region defined by the lateral extent of the crop outlet, and lateral regions extending in the lateral direction L from the central region.

In use, the header <NUM> cuts crop materials with the cutter bar <NUM>, receives the crop materials on the conveyors <NUM>, <NUM>, and conveys the crop materials back through the crop outlet <NUM> to the threshing and separating system <NUM>. One or both of the conveyors <NUM>, <NUM> may comprise a draper belt system having a segmented or continuous belt supported on rollers. At least two of the rollers are configured to apply some degree of tension to the belt, to ensure that the belt does not slip on the drive roller. Maintenance on the belt is performed by releasing the tension, such as by canceling the force of a biasing spring and/or moving the rollers towards each other. Mechanisms for releasing and reapplying belt tension are described in more detail in relation to the following exemplary embodiments.

Referring to <FIG>, a first exemplary embodiment of a draper belt tensioning system <NUM> is shown. The system <NUM> connects the header frame <NUM>, and is configured to apply a tensile force to a roller <NUM> to hold the draper belt in tension. It will be appreciated that the header frame <NUM> may be any structural part of a unitary header or a multi-segment header. For example, the header frame <NUM> may be a component of a multi-segment header center section or wing section, or it may be the a component of a unitary header. The system includes a tensioner mount <NUM> that is attached to the frame <NUM>, a roller <NUM> that extends along a roller axis <NUM> from one end of the roller to the other end of the roller, and a belt tensioner <NUM> that is connected to a first end of the roller <NUM> and is selectively connectable to the tensioner mount <NUM>. The roller <NUM> is mounted on an axle, bearings or the like to allow the roller to rotate about the roller rotation axis <NUM>, as known in the art. A draper belt <NUM> is wrapped around the roller <NUM>. The roller <NUM> is movable in a lateral direction L that is perpendicular to the roller rotation axis <NUM>, to release or apply tension to the belt <NUM>.

The belt tensioner <NUM> generally includes a travel stop <NUM>, a spring <NUM> and a threaded connector <NUM>. When the belt tensioner <NUM> is attached to the tensioner mount <NUM>, the travel stop <NUM> abuts the tensioner mount <NUM>, with the tensioner mount <NUM> located between the travel stop <NUM> and the end of the roller <NUM>. The threaded connector <NUM> is configured to move the end or the roller <NUM> closer to, and further from, the travel stop <NUM>, which is accomplished by rotating the threaded connector <NUM>. Specifically, in the shown example, the threaded connector <NUM> comprises a threaded portion of a bolt that is threaded into a threaded hole in a receiver <NUM> mounted to the end of the roller <NUM>. The spring <NUM> is captured between the head <NUM> of the bolt and the tensioner mount <NUM>. In this case, the end of the spring <NUM> that is in contact with the tensioner mount <NUM> acts as the travel stop <NUM>. Rotating the bolt head <NUM>, such as by using a manual tool (socket or wrench) or a power tool, changes the distance between the bolt head <NUM> and the receiver <NUM>, thereby compressing the spring <NUM> to different degrees. The restoring force of the spring <NUM> moves the roller <NUM> in the lateral direction L, and generates a tension force in the belt <NUM>.

<FIG> shows the tensioning system <NUM> in the fully-tensioned state. In this state, the spring <NUM> is preloaded to generate the desired tension force in the belt <NUM>. When it is desired to remove or service the belt <NUM> or roller <NUM>, the operator can rotate the bolt head <NUM> (and thus the threaded connector <NUM>) to release tension from the spring <NUM>. For example, <FIG> shows the threaded connector <NUM> being backed out of the receiver <NUM> a sufficient distance to reduce the tension in the spring <NUM> to zero, or to a relatively low level. When the spring tension is sufficiently reduced, the operator can move the belt tensioner <NUM> through an opening <NUM> through the tensioner mount <NUM>, to remove the travel stop <NUM> from the tensioner mount <NUM>, such as shown in <FIG>. In this position, the roller <NUM> is fully released from the tensioner mount <NUM> and is free to move laterally to allow belt service and replacement.

This configuration is expected to provide various advantages. For example, the travel stop <NUM>, spring <NUM> and threaded connector <NUM> can be removed from the tensioner mount <NUM> without disassembling them from each other, and without detaching them from the roller <NUM>. This allows an operator to detach the roller <NUM> for service without risking the loss of the belt tensioner components, and without having to reassemble the parts. Such benefits are particularly helpful in relation to certain existing products, in which a tensioning bolt must be completely removed to release the roller (requiring many turns of the bolt, even after spring tension is released), and reassembly requires the operator to insert bolts into blind nuts or the like. The advantages become greater when such service work is being performed in the field during the harvesting operation.

The direction in which the belt tensioner <NUM> moves to release the travel stop <NUM> from the tensioner mount <NUM> may have a bearing on other aspects of the mechanism design. For example, if the opening <NUM> is positioned to require the belt tensioner <NUM> to pivot in a direction that is not perpendicular to the roller rotation axis <NUM>, it might be necessary to provide an articulated joint to allow such motion. In the example of <FIG>, the receiver <NUM> is formed as a spherical rod end fitting that is connected to the roller axle <NUM> by a bolt <NUM>, to allow the displacement necessary to release the belt tensioner <NUM> from the tensioner mount <NUM>. Other mechanisms (e.g., ball joints or elastomeric bushings) may be used in other embodiments. If the opening <NUM> is configured to allow the belt tensioner <NUM> to release by rotating the belt tensioner in a plane perpendicular to the roller rotation axis <NUM> (such as in <FIG>), it may not be necessary to provide an articulated joint.

For illustration purposes, <FIG> show only the portion of the tensioning system <NUM> located at one end of the roller <NUM>. At the other end, the roller <NUM> may be mounted by a second tensioner mount and a second belt tensioner, which may be identical to or different from the system at the other end of the roller.

<FIG> shows another example of a belt tensioning system <NUM>. Here, the belt tensioning system <NUM> includes once again includes a tensioner mount <NUM> attached to the header frame, a roller <NUM>, and a belt tensioner <NUM> that selectively connects the roller <NUM> to the tensioner mount <NUM>. The belt tensioner <NUM> includes a travel stop <NUM>, a spring <NUM>, and a threaded connector <NUM>.

As before, when the travel stop <NUM> is engaged with the tensioner mount <NUM>, the tensioner mount <NUM> is located between the travel stop <NUM> and the roller <NUM>. In this case, the threaded connector <NUM> is a threaded nut, and the travel stop <NUM> is a surface of a washer <NUM> located between the threaded connector <NUM> and the tensioner mount <NUM>.

The threaded connector <NUM> is threaded onto the end of a bolt <NUM> that extends through a passage <NUM> through the end of the roller <NUM>. The passage <NUM> may be formed, for example, through an end of an axle <NUM> upon which the roller <NUM> is mounted. The spring <NUM> is captured between the bolt head <NUM> and the axle <NUM>.

In use, the spring <NUM> generates a resilient force acting between the bolt head <NUM> and the axle <NUM>, to thereby generate tension in a belt <NUM> wrapped around the roller <NUM>. The amount of tension can be adjusted by turning the threaded connector <NUM>. When it is desired to release belt tension, the operator turns the threaded connector <NUM> to allow the bolt head <NUM> to move away from the tensioner mount <NUM>, and such rotation eventually releases all tension from the spring <NUM>. When the tension is eliminated or reduced to a low level, the operator can slide the threaded connector <NUM> and washer <NUM> through an opening <NUM> in the side of the tensioner mount <NUM>, similar to the manner shown in <FIG>.

As before, it may be necessary to provide for some rotation of the bolt <NUM> relative to the roller <NUM> to allow the belt tensioner <NUM> to release from the tensioner mount <NUM>. In this case, such motion may be provided by making the passage <NUM> large enough to allow angular displacement of the bolt <NUM>. If the passage <NUM> is large enough to risk the spring <NUM> passing through it, a washer <NUM> may be provided to prevent this from happening.

<FIG> illustrates another exemplary belt tensioning system <NUM>. In this case, the structure is the same as that of <FIG>, with two differences. First, the washer <NUM> is omitted, and the travel stop <NUM> is formed by a face of the threaded connector <NUM>. Second, a lip <NUM> is added at the end of the opening <NUM> to prevent the threaded connector <NUM> from moving out of the tensioner mount <NUM> without displacing the threaded connector <NUM> axially away from the tensioner mount <NUM>. The lip <NUM> may be helpful to hold the belt tensioner <NUM> in place during assembly and disassembly at times when there is little or no tension present to generate friction force between the travel stop <NUM> and the tensioner mount <NUM>. The lip <NUM> also might be useful to prevent the belt tensioner <NUM> from disengaging from the tensioner mount <NUM> during operation or if the tensioner mount <NUM> becomes deformed.

<FIG> shows another example of a belt tensioning system <NUM>. Here, the system <NUM> again includes a tensioner mount <NUM> attached to the header frame, a roller <NUM>, and a belt tensioner <NUM> that selectively connects the roller <NUM> to the tensioner mount <NUM>. The belt tensioner <NUM> includes a travel stop <NUM>, a spring <NUM>, and a threaded connector <NUM>. Also as before, when the travel stop <NUM> is engaged with the tensioner mount <NUM>, the tensioner mount <NUM> is located between the travel stop <NUM> and the roller <NUM>.

In this case, the threaded connector <NUM> is provided as a threaded collar that surrounds the belt tensioner shaft <NUM>. An adjustment nut <NUM> also surrounds the shaft <NUM>, and has inner threads that match the outer threads of the threaded connector <NUM>. Thus, rotation of the threaded connector <NUM> relative to the adjustment nut <NUM> causes the assembly to expand or contract. The threaded connector <NUM> is captured, along with the spring <NUM>, between the tensioner mount <NUM> and an end stop <NUM> located at the end of the belt tensioner shaft <NUM>. The spring <NUM>, threaded connector <NUM> and adjustment nut <NUM> are dimensioned such that the threaded connector <NUM> and adjustment nut <NUM> may be rotated relative to one another to apply tension to the spring <NUM> to generate tension in the belt <NUM>, and to release tension from the spring <NUM> to allow belt service. When the tension is removed or reduced to a low level, an operator can slide the belt tensioner <NUM> out of engagement with the tensioner mount <NUM> to allow the roller <NUM> to move freely without requiring disassembly of the belt tensioner <NUM>. The threaded connector <NUM> may be located between the tensioner mount <NUM> and the spring <NUM>, such as shown, in which case the travel stop <NUM> may comprise one face of the threaded connector <NUM> or adjustment nut <NUM>. Alternatively, the spring <NUM> or a washer (not shown) may be located to abut the tensioner mount <NUM> to form the travel stop.

The belt tensioner <NUM> may be connected to the roller <NUM> using any suitable connection. In this example, the belt tensioner <NUM> has a spherical or hemispherical rod end <NUM> that fits into a corresponding hemispherical recess in the roller axle <NUM>.

Referring now to <FIG> and <FIG>, the tensioner mount may have any suitable construction to provide a surface against which the belt tensioner operates to generate tension in the belt, while also allowing the belt tensioner to selectively release the tensioner mount.

In <FIG>, the tensioner mount <NUM> is formed as a cylindrical tube having an opening <NUM> along one side. The end of the tube facing away from the roller is configured as an engagement surface that is sized to engage the travel stop to prevent the spring tensioner <NUM> from passing through the tube. The side opening <NUM> is sized to allow the shaft of the belt tensioner <NUM> to pass through.

<FIG> shows a modification of the embodiment of <FIG>. As before, the tensioner mount <NUM> comprises a cylindrical tube <NUM> having an opening <NUM> through one side, and an engagement surface <NUM> facing away from the roller. In this case, however, a cover <NUM> is provided to selectively close the opening <NUM>. For example, the cover <NUM> may be formed as a tubular section that fits the opening <NUM>, and is attached to the remainder of the tensioner mount <NUM> by a pivot <NUM>. The cover <NUM> may or may not form a portion of the engagement surface <NUM>.

<FIG> shows another example of a tensioner mount <NUM>. In this case, the tensioner mount <NUM> is formed as a plate <NUM> forming an engagement surface facing away from the roller. The plate <NUM> has a notch <NUM> extending through it. The notch <NUM> is open to one side to allow the belt tensioner shaft <NUM> to pass through by moving it in the lateral direction. The notch <NUM> may have a U-shape or any other suitable shape sized for receiving the belt tensioner shaft <NUM> while preventing the travel stop from passing through in the axial direction. If desired, a safety pin <NUM> may be provided to prevent inadvertent release of the belt tensioner shaft <NUM> from the notch <NUM>.

<FIG> shows yet another embodiment of a tensioner mount <NUM>. In this case, the tensioner mount <NUM> comprises a plate <NUM> forming an engagement surface facing away from the roller. The plate <NUM> has an enclosed passage <NUM> having a first portion <NUM> and a second portion <NUM> that are joined together to form a single continuous opening. The first portion <NUM> is dimensioned to receive the belt tensioner shaft <NUM> while preventing the travel stop from passing through. The second portion <NUM> is dimensioned to allow the travel stop and the remaining portions of the belt tensioner to pass through. In use, an operator can release tension on the belt tensioner, and then slide it sideways to the second portion <NUM> to allow it to move freely through the second portion <NUM> of the opening <NUM>.

<FIG> shows another embodiment of a tensioner mount <NUM>. In this case, the tensioner mount again includes a plate <NUM> having a single opening <NUM> that is large enough to allow the travel stop of the belt tensioner to pass through. A notched aperture plate <NUM> is provided to selectively overlap the plate <NUM> and opening <NUM>, and is dimensioned to prevent the travel stop from passing through the opening <NUM>. Thus, the aperture plate <NUM> cooperates with the plate <NUM> to form an engagement surface facing away from the roller to hold the travel stop of the belt tensioner. To release the belt tensioner, the operator reduces or removes tension on the spring, slides the aperture plate <NUM> out of the way, and then passes the travel stop and remaining portions of the belt tensioner through the opening <NUM>.

<FIG> illustrate another exemplary embodiment of a belt tensioner system <NUM>. In this case, the belt tensioner system <NUM> includes a first belt tensioner <NUM> connected to a first end <NUM> of a roller <NUM>, and a second belt tensioner <NUM>' connected to a second end <NUM>' of the roller <NUM>. Each belt tensioner <NUM>, <NUM>' comprises a travel stop <NUM>, <NUM>', a spring <NUM>, <NUM>', and a threaded connector <NUM>, <NUM>'.

In this case, the threaded connectors <NUM>, <NUM>' are bolts that extend from bolt heads <NUM>, <NUM>' to threaded ends that are threaded into corresponding holes at the respective ends <NUM>, <NUM>' of the roller <NUM>. The travel stops <NUM>, <NUM>' are formed as collars that surround the threaded connectors <NUM>, <NUM>', and the springs <NUM>, <NUM>' are captured between the travel stops <NUM>, <NUM>' and the bolt heads <NUM>, <NUM>'.

Each travel stop <NUM>, <NUM>' also includes a pin <NUM>, <NUM>' that engages a corresponding track <NUM> in a respective tensioner mount <NUM>, <NUM>'. The tensioner mounts <NUM>, <NUM>' are mounted to the header frame and provide surfaces against which the pins <NUM>, <NUM>' can apply pressure to tension the belt. As shown in <FIG>, the tracks <NUM> each have a first portion <NUM> and a second portion <NUM>. Each first portion <NUM> has an engagement surface <NUM> facing away from the roller <NUM>. The engagement surface <NUM> is configured to receive a respective pin <NUM>, <NUM>' to hold the pin <NUM>, <NUM>', and thus the travel stop <NUM>, <NUM>', at a first distance from the roller <NUM>. The second portion <NUM> of the track is adjacent the first portion <NUM>, and comprises a slot that extends towards the roller <NUM>.

In use, the threaded connectors <NUM>, <NUM>' are rotated to compress or decompress the springs <NUM>, <NUM>' to generate or release tension on the roller <NUM>. When the tension is sufficiently low or entirely removed, the operator can move the belt tensioners <NUM>, <NUM>' to remove the pins <NUM>, <NUM>' from the respective engagement surfaces <NUM>, whereupon the pins <NUM>, <NUM>' and the travel stops <NUM>, <NUM>' may slide along the slots <NUM> to release the roller <NUM> for service. To facilitate simple operation of the mechanism, the first travel stop <NUM> may be connected to the second travel stop <NUM>' by a crossbar <NUM>.

Another exemplary embodiment of a draper belt tensioning system <NUM> is shown in <FIG>. In this case, a single belt tensioner <NUM> is joined to both ends of a roller <NUM> by a rigid crossbar <NUM>. The belt tensioner <NUM> may comprise any type of belt tensioner such as previously described herein. In this example, the belt tensioner is constructed like the belt tensioners <NUM>, <NUM>' in <FIG>, and includes a spring <NUM> and a travel stop <NUM>. The travel stop <NUM> is mounted in a tensioner <NUM>, via laterally-extending pins <NUM> that fit into a corresponding slot in each tensioner <NUM>. The tensioner <NUM> is attached to the frame of the header. Operation is the same as in <FIG>.

The foregoing embodiments may provide various advantages, but it is expected that all or most embodiments will be helpful to alleviate some difficulties with operating existing belt tensioning systems. In particular, where a typical belt tensioning system requires the operator to completely remove tensioner bolts holding the roller, the foregoing embodiments allow the roller to be de-tensioned for service without disassembling the belt tensioners. In use, the operator adjusts one or both belt tensioners by rotating the threaded connector to move the end of the roller some distance away from the tensioner mount, and moving the belt tensioner out of engagement with the tensioner mount. With the belt tensioner disengaged from the tensioner mount, the operator can move the roller further from the tensioner mount without resistance from the belt tensioner, to allow relatively fast and simple service.

However, it is expected that embodiments will have particular utility in agricultural combines such as described in relation to <FIG>, to improve the serviceability of such equipment both in the shop and in the field.

Claim 1:
A draper belt tensioning system comprising:
a frame (<NUM>, <NUM>) having a first tensioner mount (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>);
a roller (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) extending along a roller rotation axis (<NUM>) from a first roller end to a second roller end, the roller being movable relative to the frame along a lateral direction (L) that is perpendicular to the roller rotation axis; and
a first belt tensioner (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) connected to the first roller end and selectively connectable to the first tensioner mount, the first belt tensioner comprising:
a first travel stop (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) configured to selectively abut the first tensioner mount with the first tensioner mount between the first travel stop and the first roller end,
a first spring (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>),
a first threaded connector (<NUM>, <NUM>, <NUM>, <NUM>) configured to move the first roller end closer to and further from the first travel stop upon rotation of the threaded connector, and
wherein the first travel stop, first spring and first threaded connector are removable from the first tensioner mount without disassembly from each other and without disassembly from the first roller end
characterized in that
the first belt tensioner comprises a threaded hole (<NUM>) connected to the first roller end, and the first threaded connector comprises a threaded rod that is rotationally engaged with the threaded hole, or
the first belt tensioner comprises a threaded rod fixed to the first roller end, and the first threaded connector comprises a threaded nut (<NUM>) rotationally engaged with the first threaded rod.