A new design for a gate valve comprises a rotating shaft with a head that can be mated to a drill bit, allowing the valve to be operated by use of a powered rotary tool such as an impact drill rather than the more difficult, traditional manual wheel or wrench. The shaft rotates freely while remaining mated to the gate valve, which in turn moves up or down to open or close the valve.

BACKGROUND

The standard gate valve is used in mines, factories, power plants, and other places all over the world. The gate is designed to start or stop the flow of fluids and slurries, and more rarely to regulate flow rate. The working component of the gate is a plane or wedge which slides into place perpendicular to the flow within a pipe valve. When lowered, the plane blocks the flow; when raised, the plane allows the fluid to flow unrestricted. When a gate valve is used to regulate the flow, partially raising or lowering the gate will change flow rate.

In the prior art, a typical example of a gate valve is lowered by turning a wrench or handle about a threaded shaft. The handle is mated to a rotatable bushing and threaded nut in such a way that the handle does not move up or down. The threaded shaft is mated to the gate such that it cannot rotate; as a result, turning the handle causes the shaft to raise or lower rather than rotating; the rotating wheel or wrench is not raised or lowered during normal operation. Due to cost or to conditions in the valve's environment, manually operated valves remain prevalent in the industry and will remain so for the foreseeable future. However, manually-operated valves face continuing problems due to the effort involved in their operation. Slurries and acids tend to foul working surfaces and shaft threads and make the valves increasingly difficult to operate. Even under normal conditions, turning the valves is a physically-demanding task that may take ten or fifteen minutes.

Mines in particular are sensitive to the problems of manual valves in conditions prohibitive to electric valves. Slurries contain sediments, acids, and other byproducts of the ore concentrate which can quickly foul a threaded shaft beyond use in the uncontrolled outdoor or underground environments common to mines. Industry practice is to simply replace the valves on a regular basis; as such, mines have the frequent opportunity to update their valve technology, but no new valves have been introduced which adequately address the problems of the current design. A heretofore unaddressed need exists for a device which can ameliorate these issues.

FIG. 1illustrates a cross-section view of a typical example of the prior art gate valve30. The valve pipe12connects to surrounding pipes to allow fluids to flow. A gate block14permits or restricts flow within the valve pipe12through the prior art gate valve30. The interior of the gate block14comprises a shaft lock16which grips the bottom of the shaft18and prevents said shaft18from rotating. A user applies rotational force to the handle22. Said rotational force interacts with the threading20to create upward force on the shaft18, which further translates to the gate block14. This force opens and closes the valve.

Another example of prior art includes knife gates, which have a narrower gate blocking the flow through the valve but otherwise operates on a similar principle—the shaft does not rotate with the handle; rather, torque applied to the handle moves the shaft up and down with the gate. A typical example of a prior art knife gate comprises four struts supporting a threaded mount. The shaft passes through the threaded mount and extends down to the valve body where it immovably mates with the knife gate. A handle is mounted onto the shaft outside of the threaded mount; just like the gate valve, torque applied to the handle applies forces through the threading on the threaded mount and the threaded portion of the shaft to move the shaft and gate up or down without rotating the shaft.

FIG. 2illustrates a typical example of a prior art knife gate valve40. Like the prior art gate valve30, this embodiment of the prior art comprises a handle22, a threaded shaft18, and a valve pipe12. Instead of a gate block14, this embodiment comprises a knife gate24joined to the shaft18by a coupling26which raises when the threaded shaft18is raised by the action of the handle22against the nut28and bushing29.

SUMMARY

The power-driven gate valve presents a solution to the difficulties of turning these heavy valves. In the preferred embodiment, top end of the threaded shaft is a hexagonal head that can be mated with an attachment to a rotary tool. The preferred embodiment is designed for use with impact drills because that type of rotary tool can shake sediment and other impediments from the threads of the threaded shaft, but any sort of handheld drill or other rotary tool will suffice. The lower end of the shaft is reshaped with a rounded head that rotatably mates with the gate rather than remaining fixed.

In the preferred embodiment, the top of the shaft comprises a hex head which can be mated to an impact drill attachment. This tool gives the worker the ability to exert much greater power than the worker could exert by hand, but is not stationary like a built-in electric motorized valve. Impact drills are preferred over other types of rotary tools because the impact action will tend to loosen the valve's moving parts by shaking out corrosion or sediments. The ability to use a rotary tool such as an impact drill saves time and effort, increasing efficiency for mines and other facilities. In the event that an impact drill is unavailable, workers can still mate a wrench or wheel to the hex head and turn the shaft manually, so the present invention comprises no loss of function over the old technology. However, unlike the typical prior art, the wheel in the present invention will be raised and lowered during operation as the hex head of the shaft rises or falls.

The bottom of the threaded shaft and the top of the gate are configured to rotatably mate with one another. In the preferred embodiment, the lower end of the threaded shaft comprises a round section at the bottommost end of the threaded shaft. Above the bottommost end is a section of the shaft with a smaller diameter than the rest of the shaft. The gate is shaped with a cutout slot around its perimeter; the cutout slot at its narrowest is preferably slightly wider than the round section of the threaded shaft. The cutout slot is also preferably slightly wider at its widest than the maximum diameter of the threaded shaft. The threaded shaft's round section is mated to the cutout portion of the plane such that the shaft can rotate and apply upward or downward force to the plane. When the threaded shaft rotates in its housing, it travels up or down according to its direction of rotation. The gate is restricted to upward or downward motion within its frame. When the two parts are mated together, the threaded shaft's rotation raises or lowers both the shaft and the gate within the valve. The threads of the threaded shaft interact with threads in the fixed shaft bushing rather than in a rotatable bushing, handle, and nut. As a result of this design, the shaft rotates as it moves up and down against the threads of the bushing. This action stands in contrast to the prior art where a shaft moves up and down without rotating and all rotational force is directed up and down by the threading on a non-rotating shaft mated to a plane, said plane being free to move only up or down. The use of a rotating shaft in the preferred embodiment of the present invention enables the use of the hex head and impact drill components described above. Without the features of the present invention, use of a handheld drill is impractical.

An alternate embodiment of the powered gate valve is a powered knife gate valve. The powered knife gate valve comprises a thin knife gate and a thin housing to stop or regulate fluid and slurry flow through the pipe. As with the gate valve, the knife gate valve comprises a shaft and is designed such that said shaft rotates. The bottom portion of the shaft rotatably mates with the top portion of the knife gate. In the prior art, the shaft is fixed to the knife gate. In contrast, this embodiment of the present invention encloses the bottom portion of the shaft in a coupling, said coupling comprising two parts which are fixed to the knife gate. The shaft can rotate freely within the coupling but cannot be separated from said coupling without first disassembling the coupling.

Further alternate embodiments may fashion the hex head with a different number of sides; for example, a four-sided square head, or a five-sided pentagonal head. More sides tend to increase the head's durability, while fewer sides tend to make the head easier to torque. The hex head remains the preferred embodiment both for its balance of durability and torque and in order to make the present invention compatible with existing tool bits.

Yet further alternate embodiments would incorporate the rotating threaded shaft, hex head, and any variants thereof into the designs of other types of gate valves such as globe valves, ball valves, butterfly valves, and others.

The foregoing and other features and advantages of the power-driven gate valve will be apparent to those of ordinary skill in the art from the following more particular description of the invention and the accompanying illustrations.

DESCRIPTION OF THE EMBODIMENTS

FIG. 3represents a side view of the preferred embodiment of the power-driven gate valve10. The pipe100is fitted to an existing pipeline where it is necessary to stop and start flow or, less commonly, to regulate flow rate. The gate200lies with the pipe100. The valve attachment300directly above the gate200is secured in place by a bonnet310. Directly above the valve attachment300is the packing box400, and above that is the bushing501which is located in the yoke500. The yoke500also contains the fixed threading510which interacts with the working threads610of the threaded shaft600. The fixed threading510remains fixed in place during normal operation of the power-driven gate valve10. At the top end of the threaded shaft600is the top portion620, preferably embodied as a hex head compatible with an impact drill bit. The preferred embodiment further comprises grease inserts410near the moving parts.

FIG. 4represents the gate200, threaded shaft600, and wheel700. The gate200lies entirely within the body of the power-driven gate valve10, while the threaded shaft600partially emerges during operation. The wheel700remains outside the body of the power-driven gate valve10at all times; in fact, the wheel700can be removed entirely in some embodiments, though doing so is not necessary even in order to use a powered rotary tool as intended. The top portion620of the shaft mates with the wheel700or with a powered rotary tool. When the threaded shaft600rotates, working threads610of the threaded shaft600push against the fixed threading510to raise and lower the threaded shaft600as well as the rotatably mated gate200.

The threaded shaft600comprises a rounded bottom end630and rounded cutout640at its lower end. The rounded cutout640allows the rotatable mating of flanges210from the gate200in order to pull the gate200upward, while the rounded bottom end630presses directly on the gate200in order to push the gate200downward. The flanges210may include planar sidewalls on the sides of the gate200. The flanges210may be spaced apart from one another along an axis orthogonal to a flow within the pipe100. This spacing may allow a user to slide the rounded bottom end630of the threaded shaft600into or out of the flanges210in the direction orthogonal to a flow within the pipe100when the threaded shaft600and the gate200are not assembled within the gate valve10.

An alternate embodiment of the present invention is the knife gate valve80shown inFIG. 5. A knife gate800rests within a frame810. When open, the knife gate800is withdrawn through a packing box820. The packing box820rests between a plurality of yokes830which support a threaded bushing840. Said threaded bushing840mates with the threaded shaft600, preferably one identical to the preferred power-driven gate valve10embodiment of the present invention including its rounded bottom end630and rounded cutout640(not shown), such that the threaded shaft600moves up or down as it rotates. A grease insert860on the threaded bushing840enables easier maintenance such that the threaded shaft600continues to move easily and smoothly. Below the threaded bushing840, he threaded shaft600rotatably mates with a coupling870which is immovably fixed to the knife gate800. Said coupling870preferably comprising two halves immovably mated to one another around the threaded shaft600.

FIG. 6shows a view of the thread shaft600and disassembled halves of the coupling870for the knife gate valve80alternate embodiment. The rounded bottom end630and rounded cutout640are shown.

The top portion620is also visible in its preferred hex shape. The two halves of the coupling870preferably comprise a grease insert860to maintain the smooth movement of the threaded shaft600.

FIGS. 7A-7Bshow the use of a power drill701and impact drill702to operate the power-driven gate valve.

The embodiments of the present invention described above, particularly the preferred embodiments, merely set forth a clear understanding of the principles of the invention. Many variations and modifications may be made to the above-described embodiments of the invention without departing substantially from the spirit and principles of the invention. All such modifications and variations are intended to be included herein within the scope of this disclosure and the present invention and protected by the following claims.