Abstract: A heavy-duty industrial transmission is provided that can be implemented in a frac pump system with planetary gearsets with straightforward shift methodologies, slow back-driven speeds, and no recirculating torque in any of the ranges. The heavy-duty transmission has a high number of ranges and may be configured with no reverse range, no countershaft, no overdrive range(s), small and consistent steps of ratios between ranges, and a deep or large reduction ratio of the lowest range, such as at least about a 5:1 reduction. The heavy-duty industrial transmission may have a four-stage planetary arrangement that is configured to provide nine (9) ranges for the transmission that only requires two double pack shifts, with the remaining shifts being single pack shifts.

Abstract: A heavy-duty industrial transmission is provided that can be implemented in a frac pump system with planetary gearsets with straightforward shift methodologies, slow back-driven speeds, and no recirculating torque in any of the ranges. The heavy-duty transmission has a high number of ranges and may be configured with no reverse range, no countershaft, no overdrive range(s), small and consistent steps of ratios between ranges, and a deep or large reduction ratio of the lowest range, such as at least about a 5:1 reduction. The heavy-duty industrial transmission may have a four-stage planetary arrangement that is configured to provide nine (9) ranges for the transmission that only requires two double pack shifts, with the remaining shifts being single pack shifts.

Abstract: A balanced clutch system is provided for use in a transmission. The balanced clutch system includes a clutch assembly that has a clutch piston and a balance piston that cooperate with a clutch piston cavity and a balance piston cavity. Each of the clutch piston cavity and balance piston cavity receives a continuous supply of fluid and establishes a centrifugal head pressure therein, during use. The centrifugal head pressure established in the balance piston cavity contributes to a force that opposes a self-engaging tendency of the clutch assembly that is created by the centrifugal head pressure established within the clutch piston cavity.

Abstract: A balanced clutch system is provided for use in a transmission. The balanced clutch system includes a clutch assembly that has a clutch piston and a balance piston that cooperate with a clutch piston cavity and a balance piston cavity. Each of the clutch piston cavity and balance piston cavity receives a continuous supply of fluid and establishes a centrifugal head pressure therein, during use. The centrifugal head pressure established in the balance piston cavity contributes to a force that opposes a self-engaging tendency of the clutch assembly that is created by the centrifugal head pressure established within the clutch piston cavity.

Abstract: The present invention is a pressure regulator for regulating a fluctuatable fluid pressure of a fluid flow, the fluid flow being received from a first device and being transmitted to a second device, including a spool valve being translatable between a closed non-regulating disposition and an open regulating disposition, a throttled portion of a fluid flow acting on a first spool working surface and a main portion of the fluid flow acting on a second opposed spool working surface. A method of regulating a fluctuatable fluid pressure is further included.

Abstract: A transmission housing having a modulatable power transmission therein which includes a clutch having interleaved clutch plates and having a central power transmitting shaft extending axially through the clutch. The clutch includes a fluid operated movable piston for effecting clutch operation by compression of the plates. The piston has a smaller piston area and a larger piston area, the smaller piston area has fluid flow directed to it at a variable fluid pressure whereby the clutch is modulatable. The larger piston area is adapted to have fluid flow directed thereto to effect maximum and unmodulatable engagement of the clutch. A spring loaded normally closed trigger valve controls fluid flow to the larger piston area in response to fluid pressure above a predetermined amount at the smaller piston area. The trigger valve is mounted on the outside of the transmission housing and is readily accessible for adjustment, for example.

Abstract: A transmission housing having a modulatable power transmission therein which includes a clutch having interleaved clutch plates and having a central power transmitting shaft extending axially through the clutch. The clutch includes a fluid operated movable piston for effecting clutch operation by compression of the plates. The piston has a smaller piston area and a larger piston area, the smaller piston area has fluid flow directed to it a variable fluid pressure whereby the clutch is modulatable. The larger piston area is adapted to have fluid flow directed thereto to effect maximum and unmodulatable engagement of the clutch. A spring loaded normally closed trigger valve controls fluid flow to the larger piston area in response to fluid pressure above a predetermined amount at the smaller piston area. The trigger valve is mounted on the outside of the transmission housing and is readily accessible for adjustment, for example.