Tool changer, machine tool, and method for changing tool

1. A tool machine comprising:

a tool rest having a tool shaft;

a shutter;

a base member; and

at least one tool changer unit,

wherein a first tool changer unit of the at least one tool changer unit comprises:

a tool holder that receives and holds a tool; and

a moving mechanism that has a linear motion guide that extends parallel to a first axis, the moving mechanism also having a drive source, the drive source sliding the tool holder along the linear motion guide relative to the base member,

wherein the base member supports the tool holder so that the tool holder can move forward along the first axis, which extends parallel to a longitudinal axis of the tool,

wherein the shutter is configured to be opened and closed along a direction that intersects the first axis,

wherein the tool holder comprises a clamp that is configured to sandwich a first end portion of the tool and hold the tool when the tool is moved downward, and release the tool when the tool is moved upward,

wherein the clamp is configured to move forward along the first axis toward a delivery position at which the tool is delivered,

wherein the clamp is provided at a first end of the tool holder along the first axis,

wherein the clamp and the first end portion of the tool are configured to protrude outward from the shutter such that a second end portion of the tool, which is opposed to the first end portion of the tool, remains at a position inward of the shutter when the clamp is set to the delivery position of the tool,

wherein the tool rest is configured to move toward the tool along the first axis so that the tool shaft chucks the tool, which is held by the clamp at the delivery position,

wherein a second tool changer unit of the at least one tool changer unit comprises a second tool holder that receives and holds a second tool, the second tool holder being disposed on the base member and adjacent the tool holder with respect to a horizontal direction,

wherein the second tool holder can move forward along a second linear motion guide and along a second axis that extends parallel to the first axis, and the second tool holder and the tool holder are able to be driven forward separately.

2. The tool machine as defined in claim 1 ,

wherein a third tool changer unit of the at least one tool changer unit comprises a third tool holder that receives and holds a third tool, and

the tool holder, the second tool holder, and the third tool holder are provided parallel to each other on the base member.

3. The tool machine as defined in claim 1 ,

wherein the clamp comprises a pair of clamp arms that are rotatable in a vertical plane and are open on a side of the clamp, and the pair of clamp arms are biased in a direction in which the pair of clamp arms are closed.

4. A method for performing a tool change with the tool machine of claim 1 , the method comprising:

opening the shutter;

selecting one of the first tool changer unit that includes the tool holder for holding the tool and the second tool changer unit that includes the second tool holder for holding the second tool;

moving the selected one of the first tool changer unit and the second tool changer unit forward such that when the first tool changer unit is selected, the tool is moved forward to the delivery position, and when the second tool changer unit is selected, the second tool is moved forward to a second delivery position;

moving the tool rest toward the selected one of the first tool changer unit and the second tool changer unit such that when the first tool changer unit is selected, the tool rest chucks the tool, and when the second tool changer unit is selected, the tool rest chucks the second tool; and

moving the tool rest upward so as to remove the tool from the tool holder when the first tool changer unit is selected and remove the second tool from the second tool holder when the second tool changer unit is selected.