Abstract: A method for monitoring the spindle preload amount of a spindle by: S1 obtaining a spindle preload amount through a PPC Preload Analyzer; and S2 obtaining an axial force sensor output of the spindle through an axial force sensor, wherein the axial force sensor output is calibrated using the spindle preload amount that is obtained through the PPC Preload Analyzer; establishing a relationship between the spindle preload amount and the axial force sensor output, then regarding the axial force sensor output as the spindle preload amount, and then monitoring the spindle preload amount by monitoring the axial force sensor output.

Abstract: A method for monitoring the spindle preload amount of a spindle by: S1 obtaining a spindle preload amount through a PPC Preload Analyzer; and S2 obtaining an axial force sensor output of the spindle through an axial force sensor, wherein the axial force sensor output is calibrated using the spindle preload amount that is obtained through the PPC Preload Analyzer; establishing a relationship between the spindle preload amount and the axial force sensor output, then regarding the axial force sensor output as the spindle preload amount, and then monitoring the spindle preload amount by monitoring the axial force sensor output.

Abstract: A tool holder assembly includes a holder body, a pull stud and a flow adjustment unit. The holder body has a holder coolant channel extending through a first end and a second end thereof. The pull stud has an insertion potion, a grip portion, and a longitudinal passage extending through the insertion portion and the grip portion, and fluidly communicating with the holder coolant channel. The flow adjustment unit includes a connection tube that extends into the longitudinal passage and projects outwardly from the grip portion, a resilient member urging the connection tube to project outwardly from the grip portion, and a flow guide channel extending through the connection tube and fluidly communicating with the holder coolant channel.

Abstract: A tool holder assembly includes a holder body, a pull stud and a flow adjustment unit. The holder body has a holder coolant channel extending through a first end and a second end thereof. The pull stud has an insertion portion, a grip portion, and a longitudinal passage extending through the insertion portion and the grip portion, and fluidly communicating with the holder coolant channel. The flow adjustment unit includes a connection tube that extends into the longitudinal passage and projects outwardly from the grip portion, a resilient member urging the connection tube to project outwardly from the grip portion, and a flow guide channel extending through the connection tube and fluidly communicating with the holder coolant channel.

Abstract: A spindle and interior cooling circuit module for delivery cryogenic fluids. The spindle has an interior coaxially equipped with a mandrel and a drawbar. The drawbar has an interior coaxially equipped with a small diameter tube. An insulated layer coated between the interior wall of drawbar and the exterior wall of insulated layer. The insulated layer, made of thermal insulation material, lowers the thermal transmission effect between the small diameter tube and the drawbar of a spindle when the cryogenic fluids is delivering.