TOOL CHANGER, MACHINE TOOL, AND METHOD FOR CHANGING TOOL

Abstract

A tool changer includes at least one tool changer unit, wherein the at least one tool changer unit includes: a tool holder that receives and holds a tool; a base member that supports the tool holder so that the tool holder can be slid along a longitudinal direction of the tool; and a moving mechanism that slides the tool holder relative to the base member.

Claims

1. A tool changer comprising: at least one tool changer unit, wherein the at least one tool changer unit comprises: a tool holder that receives and holds a tool; a base member that supports the tool holder so that the tool holder can be slid along a longitudinal direction of the tool; and a moving mechanism that slides the tool holder relative to the base member.

2. The tool changer as defined in claim 1, comprising: a plurality of the tool changer units that are provided parallel to each other in the longitudinal direction.

3. The tool changer as defined in claim 1, wherein the tool holder comprises a holding member that sandwiches and holds the tool when the tool is moved downward, and releases the tool when the tool is moved upward.

4. The tool changer as defined in claim 3, wherein the holding member comprises a pair of clamp arms that are open on an upper side, and the pair of clamp arms are biased in a direction in which the pair of clamp arms are closed.

5. The tool changer as defined in claim 3, wherein the holding member is moved forward along the longitudinal direction toward a delivery position at which the tool is delivered, and the holding member is provided at a front end of the tool holder along a forward moving direction.

6. The tool changer as defined in claim 5, further comprising: a shutter that is opened and closed along a direction that intersects a forward moving path of the tool holder, wherein the holding member protrudes outward from an opening-closing position of the shutter when set to the delivery position of the tool.

7. A machine tool comprising the tool changer as defined in claim 1.

8. A method for changing a tool comprising: opening a shutter; selecting one tool changer unit that holds a desired tool from a plurality of tool changer units; moving a tool holder of the selected one tool changer unit forward along a longitudinal direction of a tool that is held by the tool holder to place a front end of the tool at a position outward from the shutter; moving a tool rest toward the tool, and causing a tool shaft that is provided to the tool rest to chuck the tool; and moving the tool rest upward to remove the tool from the tool holder.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0048] FIG. 1A is an external view illustrating a tool changer according to one embodiment of the invention in a state in which each tool (long tool) is placed at a backward position, FIG. 1B is an external view illustrating a tool changer according to one embodiment of the invention in a state in which a tool T1 has been moved forward, and FIG. 1C is an external view illustrating a tool changer according to one embodiment of the invention in a state in which a tool T2 has been moved forward.

[0049] FIGS. 2A to 2D schematically illustrate a flow in which a tool is delivered to a tool shaft that is provided to a tool rest.

[0050] FIGS. 3A to 3C illustrate an example (motion) in which a tool is received and held by a holding member.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

[0051] An example of the structure of a tool changer according to the exemplary embodiments of the invention is described below with reference to the drawings. Note that the invention is not limited thereto.

[0052] FIGS. 1A to 1C are external views illustrating a tool changer 10.

[0053] FIGS. 1A to 1C illustrate an example in which three tool changer units are provided parallel to each other. An arbitrary number of tool changer units may be provided.

[0054] Common reference signs and numbers are used for each tool changer unit.

[0055] The tool changer unit includes a base member 11, and a tool holder 12 that is slidable relative to the base member 11 along the longitudinal direction of a tool T. The tool holder 12 moves forward in the forward direction F and backward in the backward direction B as illustrated in FIG. 1A along the longitudinal direction of the tool T.

[0056] A clamp 14 (holding member) that holds the tool T is provided to the front end of the tool holder 12 in the forward direction F.

[0057] In the example illustrated in FIGS. 1A to 1C, a linear motion (LM) guide that includes an LM rail 11a and an LM block 12a is used as a slide moving mechanism, and a rod 13a of an air cylinder 13 (drive source) is connected to the rear end of the tool holder 12 in the forward direction F.

[0058] The tool holder 12 is configured so that a case 17 is supported by the upper part of brackets 17a to 17c that are vertically provided on each side of the tool holder 12, and the tool T is received in the space formed under the case 17.

[0059] A sensor 18 that detects whether or not the tool T is present, an air blow nozzle (not illustrated in the drawings), and the like are provided inside the case 17.

[0060] The sensor 18 is used to check whether or not the tool T is being held by the tool holder 12, and the air blow nozzle is used to remove chips and the like from the tool T that has been returned to the tool changer unit by blowing air.

[0061] A flexible pedestal 15 may be provided to movably hold a cable and a pipe connected to the sensor 18 and the air blow nozzle.

[0062] A Cableveyor (registered trademark) may be used as the flexible pedestal 15, for example. The flexible pedestal 15 is configured so that a cable and the like are supported and guided between a moving end 15a (that is connected to the case 17 that moves) and a fixed end 15b, while the position of the U-shaped bent part changes so as to maintain a constant radius, for example. The fixed end 15b of the flexible pedestal 15 is secured using a bracket (not illustrated in the drawings). A proximity dock 16 is provided to the flexible pedestal 15. An air cylinder 13 is driven by a proximity switch and a control section (not illustrated in the drawings), and stopped at the forward position (tool delivery position) and the backward position (tool reception position) of the tool holder 12.

[0063] FIG. 3A illustrates an example of the structure of the holding member 14 (clamp) that holds the tool T.

[0064] The clamp 14 includes right and left clamp arms 14a that make a pair and are rotatably provided to a bracket (not illustrated in the drawings) secured on the tool holder 12 using shafts 14b. The clamp arms 14a are biased by a spring material 14c in the direction in which the clamp arms 14a are closed (i.e., the direction in which the upper opening becomes narrow).

[0065] When the tool T that is situated above the clamp 14 is moved downward, clamping sections 14d are pressed outward by the outer circumferential part of the tool T against the biasing force indicated by the arrows (see FIG. 3B).

[0066] When the tool T is further moved downward, the tool T is sandwiched and held between the arc-shaped clamping sections 14d (see FIG. 3C).

[0067] Note that the tool T is removed by performing the above steps in reverse order.

[0068] A step that delivers the tool to a tool shaft 21 of a tool rest 20 is described below with reference to FIGS. 2A to 2D.

[0069] FIGS. 2A to 2D illustrate the motion of the tool T, and the case 17 and the brackets 17a to 17c of the tool changer unit, the flexible pedestal 15, and the like are omitted.

[0070] The tool shaft 21 chucks the tool T that is used for machining. The tool shaft 21 is provided to the tool rest 20 in a state in which the tool shaft 21 can be turned.

[0071] The tool rest 20 is moved in the working area in an X-axis direction, a Y-axis direction, and a Z-axis direction that are orthogonal to each other.

[0072] An area 30 in which the tool changer 10 is placed is separated by a shutter 31 of the tool changer 10 from the working area in which the tool rest 20 is placed.

[0073] When the tool shaft 21 has approached the shutter 31 (see FIG. 2A), the shutter 31 is opened by the control section (not illustrated in the drawings) in synchronization with the approach motion, is driven (see FIG. 2B), and the tool holder 12 is moved forward to a given forward position by operating the air cylinder 13. In this case, the forward position (tool delivery position) of the tool holder 21 may be set to a constant position irrespective of the length of the tool T. When the tool changer 10 includes a plurality of tool changer units, one tool changer unit that holds the desired tool is selected by the control section from the plurality of tool changer units, and the tool holder 12 included in the selected tool changer unit is moved forward.

[0074] The tool shaft 21 then chucks the shank of the tool T (see FIG. 2B) under control of the control section (not illustrated in the drawings).

[0075] When the tool rest 20 is moved upward (see FIG. 2C) under control of the control section (not illustrated in the drawings), the tool T is removed from the clamp 14.

[0076] The tool T is thus delivered to the tool shaft 21 (see FIG. 2D). As illustrated in FIGS. 2A to 2D, since only the front end of the tool T protrudes from the shutter 31 into the working area, and the rear end of the tool T remain in the area 30 other than the working area, it is possible to reduce the space within the working area that required to deliver the tool T to the tool shaft 21 from the tool holder 12.

[0077] Note that the tool T is returned to the tool changer 10 from the tool shaft 21 by performing the above steps in reverse order. In this case, the backward position (tool reception position) of the tool holder 21 may be set to a constant position irrespective of the length of the tool T.

[0078] Although only some embodiments of the present invention have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention.