A rotary union for use along an incompressible fluid path between a rotating machine component and a non-rotating machine component includes a non-rotating seal carrier including a non-rotating seal element, which together with the non-rotating seal carrier define a net hydraulic surface on an internal side and a net pneumatic surface on an external side. Contact of an incompressible fluid under pressure with the net hydraulic surface creates a closing force, and contact of a compressible fluid under pressure with the net pneumatic surface creates an opening force.

1. Device for machining

2. The invention relates to a device for machining workpieces, preferably provided for use with a handling system, consisting of at least one rotary drive unit (26), which is guided in a device housing (2) in a longitudinally movable manner and which rotatably drives a cutting tool (100), and having a feed drive unit (32, 60), which moves the rotary drive unit (26) from a rear non-working position into a front working position and vice versa.

A rotary union for use along an incompressible fluid path between a rotating machine component and a non-rotating machine component includes a non-rotating seal carrier including a non-rotating seal element, which together with the non-rotating seal carrier define a net hydraulic surface on an internal side and a net pneumatic surface on an external side. Contact of an incompressible fluid under pressure with the net hydraulic surface creates a closing force, and contact of a compressible fluid under pressure with the net pneumatic surface creates an opening force.

A spindle unit includes a casing defining a spindle housing space, a spindle housed in the spindle housing space with a gap from an inner wall of the casing and has a first large-diameter part and a second large-diameter part separated from the first large-diameter part in the axial direction, a motor coupled to a base end part of the spindle, a high-pressure air source, and a valve between the air source and an air supply path. When the valve is opened to introduce high-pressure air into the gap and the motor is rotated and the rotation speed of the spindle becomes equal to or higher than a predetermined rotation speed, the controller closes the valve to interrupt supply of the high-pressure air into the gap and the spindle is rotatably supported by a dynamic pressure air bearing enclosed in the gap and is dragged by the spindle's rotation.

A low pressure shut off for a pneumatic tool. The tool may include an air path for input air. A shaft may be positioned along the air path and movable relative to the air path between a first position and a second position. First and second pistons may be spaced axially apart along the shaft and each may extend radially outward beyond the shaft. In the first position, the first piston may extend across the air path to block the air path. In the second position, the second piston may be positioned to be acted on by air from a secondary inlet to apply a force to the second piston that overcomes a biasing force and positions the first piston to allow air to flow along the air path.

Positive feed tools that include gear heads configured to be driven by a motor. The gear heads further include a pneumatic manifold that provides for access to input/output signals to add on additional components that include additional air logic functionality. The gear head includes first and second interface positions. Each interface is configured to receive either the motor for powering the gear head or an add-on component to provide additional functionality to the tool.

Positive feed tools that include gear heads configured to be driven by a motor. The gear heads further include a pneumatic manifold that provides for access to input/output signals to add on additional components that include additional air logic functionality. The gear head includes first and second interface positions. Each interface is configured to receive either the motor for powering the gear head or an add-on component to provide additional functionality to the tool.

Feed tools and methods of use for initiating a change in a spindle feed direction from an advance direction that moves the spindle towards a workpiece to a retract direction that moves the spindle away from the workpiece. The tool and methods may use a thrust overload force that is generated on one or more of the components to initiate the shift from forward to retract and/or a lift ring that acts on one or more of the components. The tool and methods may also include a two-stage piston to accomplish the shift. The various components may be used independently or in combination within the tool.

Positive feed tools and methods of use that include a spindle with a distal end configured to receive a tool bit. The spindle is movable in a forward direction for the tool bit to act on a workpiece, and a retract direction to move the tool bit away from the workpiece. The spindle is configured to retract to a home position at which an air motor that drives the spindle is shut off. The feed tool includes a clutch to prevent jamming of the spindle at the home position in the event the air motor is not shut off at the proper time.

A positive feed tool that includes a spindle that is axially moved along a feed path to perform work on a workpiece. The tool includes a gear head with a plurality of gears configured to rotate and axially move the spindle. The gear head is designed to change the changing gears within the gear head to change feed rates on the spindle. The gears can be interchanged without a complete disassembly of the gear head.