204 determines if the pump drive 203 should be on or off and sends the appropriate signal to the pump drive 203.

The one or more sensors 205 may measure any physical characteristic or physical parameter of the lubrication system 200 and/or high-pressure pump and/or the environment. In this embodiment, one sensor 205 is shown measuring a characteristic of the fluid end 216. Also in this embodiment, the sensor 205 shown in FIG. 7 is a temperature sensor. As discussed above, there may be multiple sensors 205 measuring multiple things and providing multiple outputs to the pump drive controller 204.

The high-pressure hoses 208, low-pressure hoses 209, and low-pressure return hoses 219 and 229 are similar to the high-pressure hoses 108, low-pressure hoses 109, and low-pressure return hoses 119 and 129 in that they perform the same functions in the same manner. However, due to the differences in the lubrication system 200 from lubrication system 100, there may be changes to the fit, form and/or number of hoses 208, 209, 219, 229 as compared to the hoses 108, 109, 119, 129 of lubrication system 100.

Referring now to FIG. 7, the check/relief manifold 218 comprises a body 222, a plurality of check valves 206, and a plurality of pressure relief valves 207. In this embodiment, the plurality of check valves 206 and the plurality of pressure relief valves 207 are mounted to the exterior of the check/relief manifold 218 or installed internally within it.

The check valves 206 are similar to the check valves 106 in that they each comprise a guide stem, a body, legs, and an insert, and they perform the same function in the same manner, providing the same advantages as the check valves 106. However, as a result of the check valves 206 being mounted to the exterior of the check/relief manifold 218 or installed internally within it, the check valves 206 may differ in fit or form from check valves 106. Also in this embodiment, there are the same number of check valves 206 as plungers 211 on a one-to-one basis.

The pressure relief valves 207 are similar to pressure relief valves 107 in that they perform the same function in the same manner. However, because the pressure relief valves 207 are mounted to the exterior of the check/relief manifold 218 or installed internally within it, the pressure relief valves 207 may differ in fit or form from pressure relief valves 107. Also in this embodiment, there are the same number of pressure relief valves 207 as plungers 211 on a one-to-one basis.

To assemble the lubrication system 200, a low-pressure hose 209 connects the reservoir 201 to the pump 202. High-pressure hoses 208 further connect the output of each plunger 211 of the pump 202 to the check/relief manifold 218, and to an inlet of a corresponding check valve 206. The check/relief manifold 218 is constructed so that the hydraulic circuit from the output of each plunger 211 to the inlet of each lubrication port on the fluid end 216 is isolated from the other hydraulic circuits. High-pressure hoses 208 also connect an outlet of each check valve 206 to lubrication ports on the fluid end 216 on a one-to-one basis.

In this embodiment, the outlets of the plurality of pressure relief valves 207 each connect to low-pressure return hoses 219, which then combine within the check/relief manifold 218 and exit the check/relief manifold 218 through a single port. A single low-pressure return hose 229 connects the single port of the check/relief manifold 218 to the reservoir 201. In alternative embodiments, there may be separate ports formed for each pressure relief valve 207. In these cases, there may be separate low-pressure return hoses 229 connecting each of the separate ports to the reservoir 201.

The reservoir 201, pump 202, pump drive 203, pump drive controller 204, one or more sensors 205, and check/relief manifold 218 may be mounted on the same conveyance as the fluid end 216 separately or as a unit. Depending on the type of pump drive 203 used, the pump drive 203 may be mounted to the pump 202. Also, depending on the types of sensors 205 used, one or more sensors 205 may be mounted to the fluid end 216.

In operation, the one or more sensors 205 and the pump drive controller 204 are used to activate and deactivate the pump drive 203 in a similar fashion as the one or more sensors 105 and pump drive controller 104 discussed above. In this embodiment, the sensor 205 is a temperature sensor monitoring the temperature of the fluid end plunger.

As can be seen by comparing FIG. 2 to FIG. 8, the hydraulic circuit for this embodiment is the same as that of the previous embodiment and provides the same advantages as the previous embodiment. Specifically, that the lubricant pumped by a single plunger 211 in the pump 202 is delivered to the lubrication port of a single plunger of a fluid end section. If a restriction 217 in the circuit causes the pressure to increase beyond a predetermined limit, the pressure relief valve 207 will activate and the lubricant will flow directly back to the reservoir 201 without damaging the components in that particular fluid end section. This provides an advantage in that all the other fluid end sections will continue to receive full lubricant flow since their hydraulic circuits are isolated from the others. The primary difference between the two embodiments 100 and 200 is the addition of the check/relief manifold 218. The check/relief manifold 218 may simplify assembly by reducing the number and/or lengths of high-pressure hoses 208 and/or low-pressure hoses 209.

Referring now to FIGS. 9-10, another embodiment of a lubrication system 300 is shown. The lubrication system 300 comprises a lubricant reservoir 301, a pump 302, a pump drive 303, a pump drive controller 304, one or more sensors 305, a plurality of high-pressure conduits or high-pressure hoses 308, a plurality of low-pressure conduits or low-pressure hoses 309, a low-pressure return conduit or low-pressure return hose 329, a check/relief manifold 318, and a lubricant or lubricating medium (not shown). The lubrication system 300 is configured to be connected to a fluid end 316. The lubricant used in this embodiment has a relatively low viscosity to encourage greater volume flow at lower system pressure. The lubricant may be many things such as a lubricating oil or a lubricating grease.

The pump 302 may be a positive displacement pump and comprises an intake manifold 310, a plurality of plungers 311, and a discharge manifold 320. As with pumps 102 and 202, lubricant enters the pump 302 via an intake manifold 310, from which all the plungers 311 draw lubricant. The pump 302 also has the same number of plungers 311 as there are fluid end sections of the fluid end 316 that is being lubricated. The pump 302 differs from pumps 102 and 202 in that the plungers 311 discharge the pressurized lubricant into a common chamber or discharge manifold 320. Lubricant exits the pump 302 through a single outlet, shown in FIG. 9. A high-pressure hose 308 connects this single outlet and a single inlet of the check/relief manifold 318.

The pump drive 303 is shown as an internal combustion engine in this embodiment, however it may be an electric motor, hydraulic motor, or any other type of driver. The schematic representation of the pump drive 303 as shown in FIG. 10 illustrates that a single pump drive 303 provides power to all the plungers 311 of the pump 302, as indicated by the connecting shaft between each schematic pump symbol 311.

The pump drive controller 304 receives output from the one or more sensors 305. Applying preprogrammed logic to the output, the pump drive controller 304 determines if the pump drive 303 should be on or off and sends the appropriate signal to the pump drive 303.

The one or more sensors 305 may measure any physical characteristic or physical parameter of the lubrication system 300 and/or high-pressure pump and/or the environment. In this embodiment, one sensor 305 is shown measuring a characteristic of the fluid end 316. Also in this embodiment, the sensor 305 shown in FIG. 9 is a linear transducer. As discussed above, there may be multiple sensors 305 measuring multiple things and providing multiple outputs to the pump drive controller 304.

The high-pressure hoses 308, low-pressure hoses 309, and low-pressure return hose 329 are similar to the high-pressure hoses 108, low-pressure hoses 109, and low-pressure return hose 129 in that they perform the same functions in the same manner. However, due to the differences in the lubrication system 300 from lubrication system 100, there may changes to the fit, form and/or number of hoses 308, 309, 329 as compared to the hoses 108, 109, 129 of lubrication system 100.

Referring now to FIG. 9, the check/relief manifold 318 comprises a body 322, a plurality of check valves 306, a pressure relief valve 307, and an intake manifold 321. In this embodiment, the plurality of check valves 306 and the pressure relief valve 307 are mounted to the exterior of the check/relief manifold 318 or installed internally within it. In contrast to check/relief manifold 218, the check relief manifold 318 has a single inlet for the lubricant. That single inlet directs fluid into the intake manifold 321 of the check/relief manifold 318 from which all the check valves 306 draw lubricant.

The check valves 306 are similar to check valves 106 in that they each comprise a guide stem, a body, legs, and an insert, and they perform the same function in the same manner, providing the same advantages as check valves 106. However, as a result of the check valves 306 being mounted to the exterior of the check/relief manifold 318 or installed internally within it, the check valves 306 may differ in fit or form from check valves 106. Also in this embodiment, there are the same number of check valves 306 as plungers in the fluid end 316 on a one-to-one basis.

The pressure relief valve 307 is similar to pressure relief valve 107 in that it performs the same function in the same manner. However, since there is only one pressure relief valve 307 in this lubrication system 300, there is only a single low-pressure return conduit 329 extending from the intake manifold 321. Further, because the pressure relief valve 307 is mounted to the exterior of the check/relief manifold 318 or installed internally within it, the pressure relief valve 307 may differ in fit or form from pressure relief valves 107.

To assemble the lubrication system 300, a low-pressure hose 309 connects the reservoir 301 to the pump 302. A single high-pressure hose 308 further connects the outlet of the discharge manifold 320 of the pump 302 to the inlet of the intake manifold 321 of the check/relief manifold 318. The check/relief manifold 318 is constructed so that the hydraulic circuits from the output of each plunger 311 to the inlet of each lubrication port on the fluid end 316 are not isolated from the other hydraulic circuits. High-pressure hoses 308 connect the outlet of each check valve 306 to the lubrication ports on the fluid end 316 on a one-to-one basis.

As discussed above, the flow from the single pressure relief valve 307 exits the check/relief manifold 318 through a single low-pressure outlet. A low-pressure return hose 329 connects the single low-pressure outlet of the check/relief manifold 318 to the reservoir 301. The reservoir 301, pump 302, pump drive 303, pump drive controller 304, one or more sensors 305, and check/relief manifold 318 may be mounted on the same conveyance as the fluid end 316 separately or as a unit. Depending on the type of pump drive 303 used, the pump drive 303 may be mounted to the pump 302. Also, depending on the types of sensors 305 used, one or more sensors 305 may be mounted to the fluid end 316.

In operation, the one or more sensors 305 and the pump drive controller 304 are used to activate and deactivate the pump drive 303 in a similar fashion as the one or more sensors 105 and pump drive controller 104 are used to activate and deactivate pump drive 103. In this embodiment, the sensor 305 is a linear transducer monitoring the position of a plunger in the fluid end 316. Detection of movement by the linear transducer indicates to the pump drive controller 304 that the fluid end 316 is active. When the pump drive controller 304 receives the signal that the pump drive 303 is active, the pump drive controller 304 starts a timer. When the timer reaches a predetermined value, the pump drive controller 304 deactivates the pump drive 303, thus beginning another timer that activates the pump drive 303 when it reaches a predetermined value.

Referring now to FIG. 10, the hydraulic circuit for this embodiment shows that the lubricant pumped by the pump 302 is combined and delivered at a common pressure to the intake manifold 321 of the check/relief manifold 318. Since no two plunger packings are the same, there are different restrictions 317. The result of different restrictions 317 in this system is that the highest restriction 317 will receive the smallest amount of lubricant. However, setting the pressure relief valve 307 at the correct setting will facilitate adequate flow to all the plunger packings. The advantage of this system is a reduction in cost by eliminating multiple pressure relief valves 307 and additional high-pressure hoses 308 as compared to lubrication systems 100, 200.

Referring now to FIGS. 11-12, another embodiment of a lubrication system 400 is shown. The lubrication system 400 comprises a lubricant reservoir 401, a pump 402, a pump drive 403, a pump drive controller 404, one or more sensors 405, a plurality of high-pressure conduits or high-pressure hoses 408, a plurality of low-pressure conduits or low-pressure hoses 409, a low-pressure return conduit or low-pressure return hose 429, a check/relief manifold 418, and a lubricant or lubricating medium (not shown). The lubrication system 400 is configured to be connected to a fluid end 416. The lubricant used in this embodiment has a relatively low viscosity to encourage greater volume flow at lower system pressure. The lubricant may be many things such as a lubricating oil or a lubricating grease.

The pump 402 may be a positive displacement pump, and comprises an intake manifold 410, a plurality of plungers 411, and a discharge manifold 420. As with pump 302, lubricant enters the pump 402 via the intake manifold 410, from which all the plungers 411 draw lubricant, and discharges the pressurized lubricant into the common chamber or discharge manifold 420. Lubricant exits the pump 402 through a single outlet. A high-pressure hose 408 connects this single outlet and an inlet of the check/relief manifold 418.

The pump 402 differs from pump 302 in that the pump 402 has fewer plungers 411 than there are fluid end sections of the fluid end 416 that is being lubricated. In this embodiment, the pump 402 has three plungers 411 and the fluid end 416 has five fluid end sections.

The pump drive 403 is shown as an electric motor in this embodiment, however it may be a hydraulic motor, internal combustion engine, or any other type of driver. The schematic representation of the pump drive 403 as shown in FIG. 12 illustrates that a single pump drive 403 provides power to all the plungers 411 of the pump 402, as indicated by the connecting shaft between each schematic pump symbol 411.

The pump drive controller 404 receives output from the one or more sensors 405. Applying preprogrammed logic to the output, the pump drive controller 404 determines if the pump drive 403 should be on or off and sends the appropriate signal to the pump drive 403.

The one or more sensors 405 may measure any physical characteristic or physical parameter of the lubrication system 400 and/or high-pressure pump and/or the environment. In this embodiment, one sensor 405 is shown receiving one output from the high-pressure hose 408 between the pump 402 outlet and the check/relief manifold 418 inlet. Also in this embodiment, the sensor 405 shown in FIG. 11 is a volume flow sensor. As discussed above, there may be multiple sensors 405 measuring multiple things and providing multiple outputs to the pump drive controller 404.

The high-pressure hoses 408, low-pressure hoses 409, and low-pressure return hose 429 are similar to the high-pressure hoses 108, low-pressure hoses 109, and low-pressure return hose 129 in that they perform the same functions in the same manner. However, due to the differences in the lubrication system 400 from lubrication system 100, there may changes to the fit, form and/or number of hoses 408, 409, 429 as compared to the hoses 108, 109, 129 of lubrication system 100.

Referring now to FIG. 11, the check/relief manifold 418 comprises a body 422, a plurality of check valves 406, a pressure relief valve 407, and an intake manifold 421. In this embodiment, the plurality of check valves 406 and the pressure relief valve 407 are mounted to the exterior of the check/relief manifold 418 or installed internally within it. The check/relief manifold 418 is similar to check/relief manifold 318 in that it performs the same functions in the same manner. However, due to the difference in the lubrication system 400 from the lubrication system 300, there may be changes to the fit and/or form.

The check valves 406 are similar to check valves 306 in that they each comprise a guide stem, a body, legs, and an insert, and they perform the same function in the same manner, providing the same advantages as check valves 306. However, as a result of the changes to pump 402 as compared to pump 302, the check valves 406 may differ in fit or form from check valves 306. In this embodiment, there are the same number of check valves 406 as plungers in the fluid end 416 on a one-to-one basis.

The pressure relief valve 407 is similar to pressure relief valve 307 in that it performs the same function in the same manner. However, as a result of the changes to pump 402 as compared to pump 302, the pressure relief valve 407 may differ in fit or form from pressure relief valve 307.

To assemble the lubrication system 400, a low-pressure hose 409 connects the reservoir 401 to the pump 402. A single high-pressure hose 408 further connects the outlet of the discharge manifold 420 of the pump 402 to the inlet of the intake manifold 421 of the check/relief manifold 418. The check/relief manifold 418 is constructed so that the hydraulic circuits from the output of each plunger 411 to the inlet of each lubrication port on the fluid end 416 are not isolated from the other hydraulic circuits. High-pressure hoses 408 also connect the outlet of each check valve 406 to lubrication ports on the fluid end 416 on a one-to-one basis.

In this embodiment, the flow from the single pressure relief valve 407 exits the check/relief manifold 418 through a single low-pressure outlet. A low-pressure return hose 429 connects the single low-pressure outlet of the check/relief manifold 418 to the reservoir 401. The reservoir 401, pump 402, pump drive 403, pump drive controller 404, one or more sensors 405, and check/relief manifold 418 may be mounted on the same conveyance as the fluid end 416 separately or as a unit. Depending on the type of pump drive 403 used, the pump drive 403 may be mounted to the pump 402. Also, depending on the types of sensors 405 used, one or more sensors 405 may be mounted to the fluid end 416.

In operation, the one or more sensors 405 and the pump drive controller 404 are used to activate and deactivate and pump drive 403 in a similar fashion as the one or more sensors 105 and pump drive controller 104 are used to activate and deactivate pump drive 103. In this embodiment, the sensor 405 is a volume flow sensor measuring the volume of lubricant flow into the check/relief manifold 418. The measured value is used by the pump drive controller 404 to adjust the speed of the pump drive 403, thus increasing or decreasing lubricant flow to the check/relief manifold 418 and, by inference, flow to each plunger packing.

Referring now to