Spring actuated axially locking shaft coupling for bi-directional loading

A coupling assembly adapted to couple a first shaft with a second shaft, the coupling comprising:

• a coupling cylindrical in shape with an outer surface and an inner surface, wherein a groove is formed radially within the inner surface of the coupling and wherein a pin port is defined by the coupling;
• a plunger bore extending axially into the first shaft;
• a locking key positioned in a key port disposed in the first drive shaft, wherein the key port extends radially into the plunger bore;
• a plunger assembly comprising a plunger and a plunger spring;
• wherein the plunger of the plunger assembly retains the locking key in the groove within the inner surface of the coupling;
• a release device coupled to the pin port in the coupling and to a pin port defined in the second drive shaft;
• and
• wherein the coupling assembly is configured to transfer tensile force from the first shaft to the second shaft via the locking key in the groove within the inner surface of the coupling and the release device in the pin port in the coupling and the pin port defined in the second drive shaft.

An electric submersible pump (ESP) assembly, comprising:

• a first section including a first outer housing and a first drive shaft, wherein the first outer housing is cylindrical with an inner chamber and the first drive shaft is cylindrical with splines on an outer surface thereof, a key port, and a plunger bore;
• a second section including a second outer housing and a second drive shaft, wherein the second outer housing is cylindrical with an inner chamber and the second drive shaft is cylindrical with splines on an outer surface thereof and a pin port;
• wherein the first outer housing of the first section is mechanically coupled to the second outer housing of the second section;
• a coupling assembly comprising a coupling, a locking key, a support ring, and a release device, wherein the coupling is generally cylindrical in shape with an outer surface, a support groove, and splines formed along an inner surface thereof, wherein the support ring is cylindrical in shape with a plunger bore and coupled to the support groove, wherein the locking key is installed within the key port of the first drive shaft, and wherein the release device is coupled to a pin port in the coupling and the pin port in the second drive shaft;
• a plunger assembly comprising a plunger and a plunger spring, wherein the plunger and plunger spring are slidingly engaged with the plunger bore of the support ring, and wherein the plunger retains the locking key in a locked position in a groove within the inner surface of the coupling, and wherein the plunger spring is configured to urge the plunger to drive the locking key into the locked position in the groove within the inner surface of the coupling during assembly of the pump assembly;
• wherein the coupling assembly mechanically couples the first drive shaft and the second drive shaft;
• wherein the coupling is configured to transmit torque from the first drive shaft to the second drive shaft via the splines of the first drive shaft, the splines of the second drive shaft, and the splines of the coupling;
• and
• wherein the coupling assembly is configured to transfer tensile stress from the pin port in the second drive shaft to the pin port in the coupling via the release device and from the coupling to the key port in the first drive shaft by the groove in the coupling via the locking key.