Hinge assembly for frame having two pivot axes

A hinge assembly with two pivot axes is provided for a folding frame. One pivot axis, a working pivot axis, allows the outer wing frame to rotate while in operation to follow the ground contours by rotating relative to the adjacent frame section without creating any interference between adjacent tools mounted to the frame sections. The second pivot axis is a folding pivot axis above the frame and about which the outer wing frame rotates to fold the outer wing into the transport position. This hinge assembly when used on a five section implement frame allows the outer wing frame to both follow the ground contour and to fold into an acceptable transport position.

FIELD

This relates to a hinge assembly defining two pivot axes and in particular to a hinge assembly used in a frame of an agricultural implement to fold an outer wing frame relative to an adjacent frame section and also to provide for floating the outer wing frame relative to the adjacent frame section when in the working position to follow the ground contours.

BACKGROUND

Agricultural producers, like other producers, are constantly seeking to increase productivity. One way to increase productivity is to increase the size of the land used for production. However, while area of land may increase, the length of the season for planting a crop is generally fixed in the duration. Thus, to increase the acreage in production, the producer must either buy additional equipment and hire operators for that equipment or purchase equipment with greater productivity. One way to increase machine productivity is to increase the width of the machine.

In the case of an air seeder drill such as the John Deere 1890 air drill, the difficulty of increasing the width is attaching an outer wing of a five section frame to enable folding of the outer wing for transport and to allow the outer wing frame float when in the planting position. A pivot axis of the hinge must be such that the row openers of the outer wing do not contact adjacent row openers when the outer wing floats during planting operations.

SUMMARY

A hinge assembly with two pivot axes is provided. One pivot axis, a working axis, allows the outer wing to follow the ground contours without creating any interference between adjacent row openers. The second pivot axis, a folding axis, is above the frame and is used to fold the outer wing into the transport position. This allows the five section planter to both follow the ground contour and to fold into an acceptable transport position.

DETAILED DESCRIPTION

With reference toFIG. 1, an air-drill10is shown having a hinge assembly connecting an outer wing frame to an inner wing frame. Air-drill10has a frame12including a tongue14used to couple the air-drill to a tractor or other prime mover. The frame12consists of five sections, a center frame16, inner wing frames18,20and outer wing frames22,24. Each inner wing frame is coupled to the center frame16by hinge mechanisms to enable the inner frames to pivot from the working position shown inFIG. 1to a raised transport position, not shown. Likewise, the outer wing frames22,24are coupled to the inner wing frames by hinge assemblies to enable the outer wing frames to pivot or fold relative to the inner wing frames from the working position shown inFIG. 1to a transport position shown inFIG. 10. Each of the five frame sections carry a number of ground engaging tools, in this case, furrow openers30to open a furrow into which seed is deposited and the furrow then closed. The furrow openers extend downwardly from the frame to engage the ground when in the working position. Other types of ground engaging tools can be used with the frame such as tillage tools or fertilizer applicators. The hinge assembly is not limited by the type of ground engaging tool.

The hinge assembly, having two pivot axes, is used to connect the outer wing frame to the inner wing frame. However, the hinge assembly could also be used to attach the inner wing frames to the center frame. With reference toFIG. 2, one hinge assembly is shown. The hinge assembly34couples the outer wing frame24to the inner wing frame20. The hinge assembly34includes a pivot plate36that is pivotally coupled to the frame20by a first pin38defining a folding pivot axis26, normal to the plane of the paper ofFIG. 2. The outer wing frame24is in turn pivotally coupled to the pivot plate36by a second pin40defining a working pivot axis28, also normal to the plane of the paper. The outer wing frame24includes a weldment42having a slot44. A float stop pin46is mounted to the pivot plate36and travels in the slot44. During operation, in the working position, the outer wing frame24is allowed to pivot about the second pin40to move up and down to follow the ground contour. The slot44defines of the amount of travel permitted by the outer wing frame during operation. The second pin40thus forms a working pivot axis about which the outer wing frame24is allowed to pivot relative to the inner wing frame20when in the working position.

An actuator48, shown as a hydraulic cylinder, has an extendable and retractable rod50. The cylinder is coupled to the inner wing frame20by a pivot pin52while the rod50is coupled to the pivot plate36by a third pin54. In the working position shown inFIG. 2, hydraulic pressure is maintained in the actuator48, holding a lower stop portion56of the pivot plate against the end of the inner wing frame20. This holds the pivot plate in a fixed position relative to the frame20. This prevents rotation of the pivot plate36about the first pin38when in the working position. To fold the frame, the rod50is retracted, causing the pivot plate36to rotate counterclockwise, as viewed inFIG. 2, about the first pin38. Upon initial retraction of the rod50, the float stop pin46will travel through the slot44until it engages the slot upper end58. During this travel, the outer wing frame24will rotate clockwise about the working pivot axis. Once the float stop pin46engages the slot upper end58and the rod50continues to retract, the pivot plate36and outer wing frame24will rotate together, counterclockwise, about a folding pivot axis defined by the first pin38until the transport position is reached. The hinge assembly34provides both a working pivot axis and a folding pivot axis. However, the hinge assembly34, when the outer wing frame24reaches a vertical position while being folded into the transport position, will allow the outer wing frame24to free fall as the frame24passes over center and the float stop pin46travels from the end58of the slot44to the slot end60. This free fall of the outer wing frame24is prevented in the hinge assembly shown inFIGS. 3-10.

InFIGS. 3-10, elements of the hinge assembly134that are similar to elements in the hinge assembly34ofFIG. 2are given the same reference numeral with the addition of 100. The hinge assembly134includes a pivot plate136coupled to a riser167rigidly attached to the inner wing frame120. The pivot plate136is coupled to the riser by a first pin138defining the folding pivot axis126. The outer wing frame124is coupled to the pivot plate136by a second pivot pin140forming the working pivot axis128. SeeFIG. 5for the folding and working pivot axes126,128. The rod150of the actuator148, instead of being coupled to the pivot plate136is coupled to first and second links169and171by a third pin154. The opposite end of the first link169is pivotally coupled to the inner wing frame120by a fourth pin173. The opposite end of the second link171is coupled to the pivot plate136by a fifth pin175. The first and second links169,171provide a higher location for the third pin154as compared to the hinge assembly34ofFIG. 2, providing increased leverage to the actuator148as it moves the outer wing from the working position shown inFIG. 3to the folded transport position.

A control link177is coupled to the outer wing frame124by a sixth pin179. The opposite end of the control link contains a seventh pin, the float stop pin146. The float stop pin146is contained within a slot144in the second link171. During operation of the air-drill, the outer wing frame124is allowed to float up and down with the ground contour as the float stop pin146moves within the slot144. As is described and shown in the following figures, the control link177and slot144are configured to prevent the outer wing frame124from free falling as it passes over center when being folded from the working position to the transport position.

With reference toFIG. 4, the hinge assembly134is shown in perspective. This enables understanding of how the various components fit with one another. The front tube of the inner wing frame120and the front tube of the outer wing frame124are generally aligned with one another. The second link171is formed of a single plate. The first link169, however, is formed of a pair of bars169aand169bon opposite sides of the plate forming link171and on the outside of the two legs of the clevis181at the end of the rod150. The control link177is likewise formed of a pair of bars177aand177bon opposite sides of the second link171. The pivot plate136is formed of two plate members136aand136beach on the opposite sides of the outer wing frame124and are welded to a cross tube183. With reference toFIG. 5, a perspective view of the air-drill frame is shown with the front hinge assembly134aand a rear hinge assembly134bconnected by the cross tube183. The plate member136aof the pivot plate136of the front hinge assembly134ahas been omitted to better visualize the structure of the hinge assembly.

With reference toFIG. 6, the hinge assembly134is shown with the outer wing frame124in the working position with the outer wing frame floated downward to a lower limit. In this position, the float stop pin146is at the bottom end160of the slot144, preventing further downward movement of the outer wing frame124. InFIG. 7, the outer wing frame124is again shown in the working position. This time however the outer wing frame124has floated upward to the upper limit. The float stop pin146is at the upper end158of the slot144. Since of the control link177is pivotally connected to the outer wing frame124, the slot144can have any shape desired with the two ends defining the limits of travel for the outer wing frame while floating in the working position. However, as described below with reference toFIG. 9, the shape of the slot144is important to provide further benefits to the hinge assembly134.

InFIG. 8, the other wing frame124is shown during the initial stage of folding to the transport position. Upon initial retraction of the rod150, the pivot plate136begins rotating about the pin138. The first and second links169,171also begin to move. This causes the slot144to raise, causing the float stop pin146to move to the bottom end160of the slot144. Once the float stop pin reaches the end of the slot, continued retraction of the rod150causes of the other wing frame124to pivot along with the pivot plate136about the pin138and folding pivot axis126toward the transport position.

InFIG. 9, the outer wing frame124has been rotated to a position just past a vertical position where the weight of the outer wing frame124would cause it to rotate counterclockwise about the pin140. The outer wing frame124is stabilized by the control link177. The float stop pin146bears against the edge of the slot144applying a force in the direction of the arrow F. This force is perpendicular to the side of the slot144with a plus and minus angular range determined by the friction coefficient between the pin146and slot144such that the pin does not slide in the slot but rather remains at the slot end160, thereby holding the outer wing frame124in position and not allowing free fall of the outer wing frame.

InFIG. 10, the outer wing frame124is shown in the folded transport position. At all times during folding of the outer wing into the transport position, the float stop pin146remains at the bottom end160of the of the slot144, preventing uncontrolled rotation of the outer wing frame. The hinge assembly provides for two pivot axes, one axis being a working pivot axis128that allows the outer wing frame124to float relative to the inner wing frame120, and the other axis being a folding pivot axis126generally located vertically higher than the working pivot axis about which the outer wing frame rotates from the working position to the transport position. The hinge assembly134allows the outer wing frame124to float downward about 10° from the horizontal in the working position and to float upward about 15° from the horizontal. When folded to the transport position, the wing rotates about 155° from the horizontal working position. To unfold the frame, the rod150is extended, causing the pivot plate136and the outer wing frame124to rotate about the folding pivot axis126. At all times while unfolding, the float stop pin146remains at the lower end160of the slot144and the force acting between the float stop pin146and the slot edge is generally normal to the slot length.

It will become apparent that various modifications can be made without departing from the scope of the accompanying claims.