Pneumatic product-on-demand delivery system for an agricultural machine with a hose disconnect monitor

The present invention provides a monitor of the hose connection of a pneumatic product-on-demand delivery system in an agricultural machine. This can be done in several ways. One way is to sense the product flow in the product hose and how long it is running. If the product is constantly running through the hose, that indicates a disconnection. A second way is to sense air pressure in the product hose to determine if it is still operating under pressure. If disconnected, the air pressure will drop indicating a disconnection. A third way is to sense a current through the connection to determine if it is on or off. All of these methods produce a signal that can be fed back to a monitor at the operator station and give the operator an alert if a disconnected hose is detected.

FIELD OF THE INVENTION

The present invention is directed to a pneumatic product-on-demand delivery system for an agricultural machine and in particular to a monitor for these system.

BACKGROUND OF THE INVENTION

Pneumatic product-on-demand delivery systems have been used on agricultural seeding machines to automatically direct seed from a main seed hopper to a plurality of individual planting units. Each of the individual planting units has an auxiliary seed hopper for receiving the seed, a seed meter for metering the seed from the auxiliary seed hopper and a furrow opener for forming a planting furrow into which the metered seed is deposited. A fan is used to create pressurized air that forms an air stream on which the seed is taken to the planting units. These systems automatically replenish the auxiliary hoppers as needed. An example of a pneumatic product-on-demand delivery system is shown in U.S. Pat. No. 7,025,010.

A pneumatic product-on-demand delivery system has a series of hoses to deliver the seed from the main seed hopper to the auxiliary seed hopper. The product hose has a connection point that allows the hose to be disconnected from the hopper for the meter to be removed. If this connection works its way off while planting, then the delivery system will keep running and spread seed on the ground. This will likely not be noticed until the operator turns around at the end of the row to plant in the other direction. By that time, the system has dropped several bushels of expensive seed onto the ground which can no longer be used.

SUMMARY OF THE INVENTION

The present invention provides a sensor to monitor the product hose for failure. This can be done in several ways. One way is to sense the seed flow in the product hose and how long it is running. If the seed is constantly running through the hose, that indicates a disconnection or other hose failure such as a hole in the hose resulting in the loss of seed on the ground. A second way to detect a hose failure is to sense air pressure in the product hose to determine if it is still operating at the proper pressure. If the hose is disconnected or an air leak is present, the air pressure in the hose will drop, indicating a failure. A third way detect a hose failure is the form of a disconnection is to sense a current through the connection to determine if it is on or off. All of these methods produce a signal that can be fed back to a monitor at the operator station and give the operator an alert if a hose failure occurs.

DESCRIPTION OF THE PREFERRED EMBODIMENT

An agricultural seeding machine10comprises a frame12on which are mounted a plurality of individual planting units14. The frame12includes a tongue (not shown) to connect the machine10to a tractor (not shown). The planting units14are coupled to the frame12by a parallelogram linkage16so that the individual planting units14can move up and down to a limited degree relative to the frame12. Each of the individual planting units comprises an auxiliary seed hopper18for holding seed, a seed meter20for metering seed received from the auxiliary seed hopper18and a furrow opener22for forming a planting furrow in a field for receiving metered seed from the seed meter20. The seed is transferred to the planting furrow from the seed meter by a seed tube24. A closing assembly26is used to close the planting furrow with the seed contained therein. In the preferred embodiment the seed meter20is a vacuum seed meter, although other types of seed meters using mechanical assemblies or positive air pressure could also be used with the subject invention. It should be noted that the present invention could also be used to apply non-seed products to the field. For seed and non-seed products, the planting unit could be considered an application unit with an auxiliary hopper for holding product, a product meter for metering product received from the auxiliary hopper and an applicator for applying the metered product to a field. For example a dry chemical fertilizer or pesticide could be directed to the auxiliary hopper and metered by the product meter and applied to the field by the applicator.

The main frame12supports a main hopper30and an air pump32. The air pump32is driven by a hydraulic motor; however other motor arrangements could be used, like electric motors for driving the air pump32. The air pump32directs pressurized air to a manifold34through main air hose36. The manifold34is formed from a hollow closed tubular support of the main frame12. The manifold34is provided with a plurality of manifold outlets. Individual air supply lines38extend from the manifold outlets and direct pressurized air from the manifold34to the upstream side of the nozzle assembly39. The nozzle assembly39is located at the bottom of the main hopper30. Product located in the main hopper30flows by gravity to the nozzle assembly39. The upstream side of the nozzle assembly39is provided with a number of air inlets41corresponding to the number of air supply hoses38. The air inlets41are spaced transversely along the upstream side of the nozzle assembly39. The downstream side of the nozzle assembly39is provided with a number of product outlets43corresponding to the number of air supply hoses38. The product outlets43are also spaced transversely along the downstream side of the nozzle assembly39. The product outlets43lie opposite from the air inlets41. Each air inlet41is aligned with a respective product outlet43. Product supply hoses42extend from the product outlets43to the individual auxiliary hoppers18for directing product entrained in the air stream to the auxiliary hoppers18.

The auxiliary hopper18is connected to the product hose42through a fitting46shown inFIG. 2. Fitting46is coupled to the hopper18by use of a flange48and four fasteners49, only two of which are shown inserted through openings50arranged in a rectangular pattern. The fitting46has an inlet52(FIG. 6) connected to the hose42by a quick connect coupling54(FIG. 6). The fitting further has an outlet56shown through the broken away portion of the fitting46. The quick connect coupling54is engaged by a hose coupling58at the end of the hose42. The hose coupling58has a plurality of L-shaped slots60that receive the posts62of the quick connect coupling54. During use, it is often necessary for the operator to remove the hose42from the fitting46, thus the connection between the quick connect coupling54and the hose coupling58must be easily disconnected. But by being easily disconnected, it is possible that due to vibrations during operation, the coupling can inadvertently become disconnected. If this occurs, seed or other product, will be dumped on the ground and wasted. The system of the present invention monitors the coupling and provides an alert to the operator of a disconnection.

Various sensors can be used to determine if there is a disconnection or other hose failure. One sensor is shown inFIG. 4. A seed sensor64is provided in the hose42to sense the passage of seed there through. The seed-on-demand distribution system operates to fill the auxiliary hopper to a predetermined level. Once that level is reached, the air exit is block, causing air to stop flowing through the tube42and thus seed flow through the tube42will also stop. Seed sensor64can be any of a variety of common seed sensors. One such sensor is shown in U.S. Pat. No. 4,166,948 which comprises a LED optically exposed to the path of travel of seeds with photo-sensitive element detecting changes in light level. In normal operation, the flow of seeds in the tube42will periodically cease when the auxiliary hopper is filled, until the level of seed drops, allowing air to flow once again. If the sensor detects a continuous flow of seed over a predetermined period time without any cessation in the seed flow, that indicates the hose42is disconnected or that a hole has developed in the hose resulting in seed being dumped on the ground instead of filling the auxiliary hopper. The sensor64is connected to a monitor66by a wire68, or wirelessly, to communicate a signal to the monitor. The monitor is located at the operator station of the tractor or other towing vehicle pulling the machine10. An alert is provided by the monitor to the operator when a disconnection is detected.

FIG. 5illustrates another sensor to detect a hose disconnection. Here, a pressure sensor70is provided on the hose42to measure the air pressure within the hose. During normal operation, an air pressure elevated above the ambient pressure will be present in the hose42. However, if the hose becomes disconnected or if a leak develops in the hose, the pressure will drop to, or close to, ambient. The pressure sensor70communicates with the monitor via the wire72concerning the pressure in the hose. If the pressure falls below a predetermined value, an alert of a disconnection is provide by the monitor.

A further embodiment is shown inFIG. 6. There, electrical contact74is provided in the quick connect coupling54that mates with electrical contact76in the hose coupling58. The slots60and posts62are arranged such that when the hose42is connected, the contacts74and76engage one another to complete an electrical circuit. Contacts74and76are connected by wires (not shown) to the monitor66. If the circuit is opened, a disconnection has occurred and an alert is provided to the operator.

By monitoring and detecting a disconnection of the hose or other hose failure, lose of seed or other product can be minimized, resulting in a savings to the operator. While the invention has been shown in the context of a seeding machine, the invention can be used in other machines with other products that are conveyed by a pneumatic delivery system.