A hammer drill having a motor mounted within a body and an output spindle; a tool holder mounted on the body capable of holding a cutting tool; a hammer mechanism having a piston; a reciprocating drive for converting rotary movement of the motor into reciprocating movement of the piston; a ram reciprocatingly driven by the piston via an air spring to strike a cutting tool held in the tool holder, the hammer mechanism performing one hammer cycle each time the ram strikes a cutting tool during normal use; an air replenishment mechanism capable of refreshing the air spring during certain time periods during normal use; the air replenishment mechanism capable of being adjusted to refresh the air spring during time periods within the hammer cycle and/or the system allows different volumes of air into or out of the air spring during the refreshment time periods.

An automatic shutoff system for a hydraulic hammer is disclosed. The automatic shutoff system may include an inlet groove formed around a piston associated with the hydraulic hammer and configured to receive pressurized fluid, and an outlet groove formed around a piston associated with the hydraulic hammer and configured to discharge the pressurized fluid. The automatic shutoff system may also include an annular passage configured to allow the pressurized fluid to flow between the inlet and outlet grooves. The automatic shutoff system may further include a valve disposed upstream of the inlet groove and configured to selectively block the pressurized fluid from flowing into the inlet groove based on an operational state of the hydraulic hammer.

A processor-controlled, energy-based therapy apparatus includes a device configured to provide therapeutic energy to a patient and a processor that controls the output of the device. The output of the device is based on output profiles programmed into the processor. The output profiles include a therapeutic energy output profile and a ramp-up energy profile. The therapeutic energy output profile includes a desired target energy level and a therapeutic duration for controlling the output of the device during a therapeutic period. The ramp-up energy output profile includes an initial treatment energy level and a ramp-up duration for controlling the output of the device during a ramp-up period. The energy output specified by the ramp-up energy output profile incrementally increases over the ramp-up duration as a function of the desired target energy level and the ramp-up duration.

A processor-controlled, energy-based therapy apparatus includes a device configured to provide therapeutic energy to a patient and a processor that controls the output of the device. The output of the device is based on output profiles programmed into the processor. The output profiles include a therapeutic energy output profile and a ramp-up energy profile. The therapeutic energy output profile includes a desired target energy level and a therapeutic duration for controlling the output of the device during a therapeutic period. The ramp-up energy output profile includes an initial treatment energy level and a ramp-up duration for controlling the output of the device during a ramp-up period. The energy output specified by the ramp-up energy output profile incrementally increases over the ramp-up duration as a function of the desired target energy level and the ramp-up duration.

A hammer drill having a motor mounted within a body and an output spindle; a tool holder mounted on the body capable of holding a cutting tool; a hammer mechanism having a piston; a reciprocating drive for converting rotary movement of the motor into reciprocating movement of the piston; a ram reciprocatingly driven by the piston via an air spring to strike a cutting tool held in the tool holder, the hammer mechanism performing one hammer cycle each time the ram strikes a cutting tool during normal use; an air replenishment mechanism capable of refreshing the air spring during certain time periods during normal use; the air replenishment mechanism capable of being adjusted to refresh the air spring during time periods within the hammer cycle and/or the system allows different volumes of air into or out of the air spring during the refreshment time periods.

A hammer drill having a motor mounted within a body and an output spindle; a tool holder mounted on the body capable of holding a cutting tool; a hammer mechanism having a piston; a reciprocating drive for converting rotary movement of the motor into reciprocating movement of the piston; a ram reciprocatingly driven by the piston via an air spring to strike a cutting tool held in the tool holder, the hammer mechanism performing one hammer cycle each time the ram strikes a cutting tool during normal use; an air replenishment mechanism capable of refreshing the air spring during certain time periods during normal use; the air replenishment mechanism capable of being adjusted to refresh the air spring during time periods within the hammer cycle and/or the system allows different volumes of air into or out of the air spring during the refreshment time periods.

A self-charging assembly having a first side wall, a second side wall, a third sidewall, a first chamber, a second chamber, a first valve assembly, and a second valve assembly. The second side wall is disposed within the first side wall. The third sidewall connects the first side wall and the second side wall. The first chamber is defined by the first, second, and third sidewalls. The second chamber is disposed within the first chamber and is defined by the second side wall. The first valve assembly is configured to selectively place an interior portion of the second chamber in communication with an atmosphere outside of the self-charging assembly. The second valve assembly is configured to selectively place an interior portion of the first chamber in communication with the interior portion of the second chamber.

A self-charging assembly having a first side wall, a second side wall, a third sidewall, a first chamber, a second chamber, a first valve assembly, and a second valve assembly. The second side wall is disposed within the first side wall. The third sidewall connects the first side wall and the second side wall. The first chamber is defined by the first, second, and third sidewalls. The second chamber is disposed within the first chamber and is defined by the second side wall. The first valve assembly is configured to selectively place an interior portion of the second chamber in communication with an atmosphere outside of the self-charging assembly. The second valve assembly is configured to selectively place an interior portion of the first chamber in communication with the interior portion of the second chamber.

Illustrative embodiments of impact tools with speed controllers and methods of controlling such impact tools are disclosed. In at least one illustrative embodiment, an impact tool may comprise a ball-and-cam impact mechanism including a hammer and an anvil. The hammer may be configured to rotate about a first axis and to translate along the first axis to impact the anvil to cause rotation of the anvil about the first axis. The impact tool may further comprise a motor and a speed controller. The motor may include a rotor configured to rotate when a flow of compressed fluid is supplied to the rotor to drive rotation of the hammer of the ball-and-cam impact mechanism. The speed controller may be coupled to the rotor and may be configured to throttle the flow of compressed fluid supplied to the rotor based on a rotational speed of the rotor.

A control valve, an impact device for a rock breaking apparatus, and a method are provided. The control valve is an elongated piece with a central axis and radial outer and inner surfaces (Ros, Ris). The control valve includes several control surfaces disposed at axial distances from each other for controlling hydraulic fluid flows (Hff) in response to axial control movement (M). One or more radial surfaces of the control valve include one or more slanted surface (SS) a longitudinal direction of which have oblique orientation in relation to the central axis (Ca) of the control valve. The control valve rotates or turns during a working cycle due to hydraulic flow effecting on the slanted surfaces.