JP2021133472A - Tool changing device - Google Patents

Abstract

To provide a tool changing device in which the intrusion of foreign matters into an arm is reduced.SOLUTION: A tool changing device 10 according to the embodiment comprises: a housing 11 in which a first internal space 11a is formed; an arm 30 which has a gripping portion 32 for gripping a tool and in which a second internal space 31b is formed; a lock member 33 for pressurizing the tool gripped by the gripping portion; arm shaft 21 connected to the arm 30; a cam mechanism (a cam 17, a link 18, a rotary engaging portion 23, an ascending/descending engaging portion 26) arranged in the first internal space, and for rotating or ascending/descending the arm shaft; and a lock mechanism (a link 35, an elastic member 37) arranged in the second internal space, and for moving the lock member. The housing has a first communicative hole 11b that communicates the first internal space with the outside, and the arm shaft has a second communicative hole (axial hole 21a) that communicates the first internal space with the second internal space.SELECTED DRAWING: Figure 1

Description

The present invention relates to a tool changer.

Tool changers have been developed to change tools on the spindle of machine tools. The tool changer includes an arm for gripping the tool and a locking mechanism for locking and unlocking the gripped tool.

The lock mechanism is installed in the arm. The locking mechanism often has a link that operates by an external force and an elastic member (for example, a spring) that restores the link when no external force is applied. When this locking mechanism operates, the volume inside the arm may change and attract outside air (for example, when the tool is locked, the components of the locking mechanism move in a direction that protrudes out of the arm, thereby causing the inside of the arm to move. Increased volume and negative pressure).

Here, mist-like cutting fluid (mist) is often generated during the operation of the machine tool. This mist floats near the arm or adheres to the arm. Therefore, when the lock mechanism operates, mist may enter the arm together with the outside air. The mist in the arm can cause poor lubrication of the locking mechanism and thus damage to it. That is, the invasion of foreign matter (for example, mist) into the arm is not preferable.

Japanese Unexamined Patent Publication No. 2016-043466

An object of the present invention is to provide a tool changing device that reduces the intrusion of foreign substances into an arm.

The tool changing device according to the embodiment has a housing in which a first internal space is formed, a grip portion for gripping a tool, and an arm in which a second internal space is formed, and the grip portion. A lock member for pressing a tool gripped by the arm, an arm shaft connected to the arm, a cam mechanism arranged in the first internal space to rotate or raise and lower the arm shaft, and the second. It is provided with a locking mechanism that is arranged in the internal space of the above and moves the locking member. The housing has a first communication hole for communicating the first internal space with the outside, and the arm shaft has a second communication for communicating the first internal space with the second internal space. It has a hole.

According to the present invention, it is possible to provide a tool changing device that reduces the intrusion of foreign objects into the arm.

It is a figure which shows the tool change device which concerns on embodiment. It is a perspective view of the arm which concerns on embodiment. It is an exploded perspective view which shows the state which the arm shaft and the arm are separated. It is sectional drawing which cut the arm shaft and the arm in IV-IV of FIG. 1, and shows the connection state of an arm shaft and an arm.

The tool changing device according to the embodiment will be described in detail below with reference to the drawings. FIG. 1 shows the tool changing device 10 according to the embodiment. The tool changing device 10 includes a housing 11, a motor 13, a reduction mechanism 14, a cam 17, a link 18, an arm shaft 21, a tubular body 22, a rotary engaging portion 23, an elevating engaging portion 26, and an arm 30. Of these, the cam 17, the link 18, the rotary engaging portion 23, and the elevating engaging portion 26 form a cam mechanism for raising and lowering and rotating the arm shaft 21.

The housing 11 has an internal space 11a (first internal space) and a communication hole 11b (first communication hole). In order to maintain the lubricity of the cam mechanism, the internal space 11a contains a liquid lubricant L. As a result, the internal space 11a can be divided into a lubricating material region filled with the lubricating material L and an atmospheric region filled with the atmosphere above the lubricating material L (which may contain a component of the vaporized lubricating material L). However, the boundaries of these regions vary depending on the amount of lubricant L injected or consumed. The communication hole 11b opens in the atmospheric region, communicates the internal space 11a (atmospheric region) with the outside (atmosphere), and allows the atmosphere to flow.

The motor 13 is attached to the outside of the housing 11 and supplies a rotational force inside the housing 11. The deceleration mechanism 14 decelerates the rotation speed output from the motor 13 to an appropriate value. As an example of the reduction mechanism 14, a combination of a worm gear and a worm foil can be used, but the present invention is not limited to this, and various reduction mechanisms (for example, gears) can be used.

The cam 17 is rotated about the rotation shaft O by the motor 13 via the reduction mechanism 14. In this example, the rotation axis O is orthogonal to the axis of the motor 13, but may be parallel to each other. The cam 17 has a substantially cylindrical shape, and a groove 17a is formed on the end surface thereof, and a groove 17b (not shown) is formed on the peripheral side surface thereof. The groove 17a can be divided into sections A1 to A4. The groove 17a has a substantially arc shape in the sections A1 and A3, and has a substantially linear shape in the sections A2 and A4. The groove 17b is divided into sections B1 to B4 corresponding to sections A1 to A4 of the groove 17a. The groove 17b is substantially parallel to the circumference of the cam 17 in the sections B2 and B4, and is inclined with respect to the circumference of the cam 17 in the sections B1 and B2.

The link 18 has a link main body 18a, a fulcrum 18b, a protrusion 18c, and a protrusion 18d. The link body 18a has a rod shape or an elongated plate shape as a whole. The fulcrum 18b is arranged at one end of the link main body 18a and is rotatably fixed to the housing 11. That is, the link 18 can rotate around the fulcrum 18b. The protrusion 18c is inserted (engaged) into the groove 17a of the cam 17. The protrusion 18d is arranged at the other end of the link body 18a and engages with the elevating engagement portion 26.

The arm shaft 21 has a substantially cylindrical shape, and has an axial hole 21a, a through hole 21b, and a through hole 21c (first through hole). The axial hole 21a extends in the axial direction of the arm shaft 21. The through holes 21b and 21c are arranged in the upper part and the lower part of the axial hole 21a and penetrate between the axial hole 21a and the side surface. The axial holes 21a, through holes 21b, and 21c connect the internal space 11a (first internal space) of the housing 11 and the internal space 31b (second internal space) of the arm 30, which will be described later, to form a lubricant L. It functions as a flow path (second communication hole) of the lubricating material L that circulates. The tubular body 22 and the rotary engaging portion 23 are arranged on the upper portion of the arm shaft 21, and the elevating engaging portion 26 (guide ring) is arranged on the lower portion.

The upper end of the tubular body 22 is supported so as to be axially rotatable with respect to the housing 11. The tubular body 22 has a substantially tubular shape, and holds the upper portion of the arm shaft 21 inside the tubular body 22. The arm shaft 21 rotates integrally with the tubular body 22 and engages with the tubular body 22 so as to be able to move up and down relative to each other.

The rotary engaging portion 23 has a substantially ring shape having a concave cross section, is fixed to the outer periphery near the lower end of the tubular body 22, and can rotate together with the tubular body 22. The rotary engaging portion 23 has an engaging protrusion 23a that engages with the groove 17b.

The elevating engagement portion 26 has a substantially ring shape, is fixed to the outer periphery of the arm shaft 21, and engages with the protrusion 18d of the link 18.

Here, the movement of the arm shaft 21 when the motor 13 operates will be described. As shown below, when the motor 13 operates, the arm shaft 21 alternately moves up and down and rotates.

First, the protrusion 18c of the link 18 is arranged near the boundary between the section A1 and the section A4 of the groove 17a of the cam 17, and the engagement protrusion 23a of the rotary engaging part 23 is the boundary between the section B1 and the section B4 of the groove 17b. It is assumed that it is placed in the vicinity. When the motor 13 operates and the cam 17 rotates, the protrusion 18c of the link 18 moves in order in the sections A1, A2, A3, and A4 of the groove 17a, and the engagement protrusion 23a of the rotation engagement portion 23 It is assumed that the sections B1, B2, B3, and B4 of the groove 17b are moved in order.

When the protrusion 18c moves in the section A1 of the groove 17a and the engaging protrusion 23a moves in the section B1 of the groove 17b, the arm shaft 21 rotates without moving up and down. This can be explained as follows. That is, the groove 17b is tilted with respect to the circumference of the cam 17 in the section B1. Therefore, the engaging protrusion 23a moves in the axial direction of the cam 17 when moving in the section B1 to rotate the rotary engaging portion 23. When the rotary engaging portion 23 rotates, the tubular body 22 and eventually the arm shaft 21 rotate. On the other hand, the groove 17a has a substantially arc shape centered on the rotation axis O in the section A1. Therefore, when the protrusion 18c moves in the section A1, the distance from the rotation axis O is kept constant, so that the protrusion 18c does not substantially move up and down and the link 18 does not rotate. As a result, the protrusion 18d of the link 18, the elevating engaging portion 26, and the arm shaft 21 do not move up and down.

When the protrusion 18c moves in the section A2 of the groove 17a and the engaging protrusion 23a moves in the section B2 of the groove 17b, the arm shaft 21 moves up and down without rotating. This can be explained as follows. That is, when the protrusion 18c moves in the section A2, the distance from the rotation axis O changes, so that the protrusion 18c moves up and down (descends here), and the link 18 rotates. As a result, the protrusion 18d of the link 18, the elevating engaging portion 26, and the arm shaft 21 move up and down. On the other hand, the groove 17b is parallel to the circumference of the cam 17 in the section B2. Therefore, the engaging protrusion 23a does not move in the axial direction of the cam 17 when moving in the section B2, and the rotary engaging portion 23 does not rotate. Since the rotary engaging portion 23 does not rotate, the tubular body 22 and the arm shaft 21 also do not rotate.

Hereinafter, similarly, when the protrusion 18c moves in the section A3 of the groove 17a and the engaging protrusion 23a moves in the section B3 of the groove 17b, the arm shaft 21 rotates without moving up and down. Further, when the protrusion 18c moves in the section A4 of the groove 17a and the engaging protrusion 23a moves in the section B4 of the groove 17b, the arm shaft 21 moves up and down (here, ascends) without rotating. When the motor 13 is moved in this way, the arm shaft 21 rotates, descends, rotates, and rises in order.

Next, the details of the arm 30 will be described. FIG. 2 is a perspective view of the arm 30 fixed to the arm shaft 21. FIG. 3 is an exploded perspective view showing a state in which the arm shaft 21 and the arm 30 are separated. FIG. 4 is a cross-sectional view taken by cutting the arm shaft 21 and the arm 30 in IV-IV of FIG. 1, and shows a connected state of the arm shaft 21 and the arm 30.

The arm 30 is connected to the lower end of the arm shaft 21 and moves up and down and rotates together with the arm shaft 21. The arm 30 has a substantially rectangular parallelepiped shape, and has an arm body 31, a grip portion 32, a lock member 33, a lock shaft 34, a link 35, a pressing member 36, and an elastic member 37. The arm 30 is a so-called double arm and has a pair of grip portions 32 and a pair of lock members 33.

The arm main body 31 has a through hole 31a, an internal space 31b (second internal space), and a flow path 31c. The through hole 31a has a substantially cylindrical shape, and the arm shaft 21 is inserted and fixed.

The internal space 31b is a space for arranging the pressing member 36 and the elastic member 37. The internal space 31b is filled with the lubricating material L, and the lock shaft 34, the link 35, the pressing member 36, the elastic member 37, and the like are smoothly operated. The upper side of the internal space 31b is sealed by a vertically movable pressing member 36.

The flow path 31c communicates the through hole 21c of the arm shaft 21 with the internal space 31b of the arm body 31 so that the lubricant L can be supplied from the internal space 11a of the housing 11 to the internal space 31b of the arm body 31. .. One end side of the flow path 31c is connected to the internal space 31b. The other end side of the flow path 31c has an opening 31d that opens into the through hole 31a of the arm body 31. That is, the internal space 31b of the arm body 31 communicates with the through hole 21c (furthermore, the axial hole 21a, the through hole 21b, the internal space 11a) of the arm shaft 21 via the flow path 31c and the opening 31d.

However, as shown in FIGS. 3 and 4, the lower end of the axial hole 21a of the arm shaft 21 is opened, and the opening / closing member 41 is inserted into the opening / closing member 41 to open / close the through hole 21c. The details will be described later.

The grip portion 32 grips the tool. The lock member 33 locks the tool gripped by the grip portion 32. The lock member 33 is connected to the pressing member 36 by the lock shaft 34 and the link 35.

One end of the lock shaft 34 is connected to the lock member 33. The other end of the lock shaft 34 is rotatably connected to one end of the link 35.

The link 35 is rotatably connected to another member by the rotation shafts O1 to O3. The rotation shaft O1 is arranged at the center of the link 35 and rotatably connects the link 35 to the arm body 31. The rotation shaft O2 is arranged on one end side of the link 35, and rotatably connects the link 35 to the pressing member 36. The rotary shaft O3 is arranged on the other end side of the link 35 and rotatably connects the link 35 to one end of the lock shaft 34.

The pressing member 36 is divided into a sealing portion 361, a protruding portion 362, and a main body portion 363, and is pressed and displaced downward. The sealing portion 361 seals the internal space 31b and prevents the lubricant L from leaking from the internal space 31b. The protruding portion 362 protrudes from the arm main body 31. By pressing the protrusion 362 from above, the pressing member 36 is displaced downward. The main body 363 is connected to the link 35 by the rotation shaft O2. The elastic member 37 urges the pressing member 36 upward.

The link 35, the pressing member 36, and the elastic member 37 move the lock member 33 as follows.

When the pressing member 36 (protruding portion 362) is pressed, the pressing member 36 is displaced downward and the rotation axis O2 of the link 35 is lowered. The link 35 rotates about the rotation shaft O1 and moves the rotation shaft O3 (lock shaft 34, lock member 33) in the direction toward the arm shaft 21. As a result, the lock member 33 unlocks the tool gripped by the grip portion 32 (unlock).

When the pressing on the pressing member 36 is stopped, the pressing member 36 returns upward by the urging force of the elastic member 37, and the lock member 33 locks the tool gripped by the grip portion 32.

The tool is unlocked and locked by applying and stopping the pressure on the pressing member 36. The link 35 and the elastic member 37 function as a locking mechanism for moving the locking member 33.

When the locking mechanism operates, the pressing member 36 (sealing portion 361) that seals the internal space 31b is displaced vertically, and the volume (and thus the internal pressure) of the internal space 31b fluctuates. For example, when the tool is locked, the urging force of the elastic member 37 causes both the pressing member 36 and the lock shaft 34 to move in the direction of protruding outside the arm 30, so that the volume of the internal space 31b increases and the inside of the arm 30 (internal space). A negative pressure is generated in 31b). Such a change in volume (internal pressure) can cause the inflow of outside air into the internal space 31b through the gap between the lock shaft 34 and the arm body 31 and the like. As a result, foreign matter (mist or the like) may enter the internal space 31b of the arm 30 and cause poor lubrication of the lock mechanism, which in turn may cause damage to the lock mechanism.

However, in the present embodiment, the internal space 31b of the arm 30 communicates with the internal space 11a of the housing 11 having the communication hole 11b (air bleeding duct). Therefore, the volume change of the internal space 31b is absorbed on the housing 11 side.

That is, as the volume of the internal space 31b changes, the lubricant L flows in and out from the internal space 11a of the housing 11 to the internal space 31b of the arm 30. As a result, the lubricating material L is always arranged in the internal space 31b in an amount corresponding to the volume, and even if the volume of the internal space 31b changes, the outside air or the like does not flow into the internal space 31b.

At this time, the change in the volume of the internal space 31b causes an increase or decrease in the amount of the lubricant L in the internal space 11a, and this increase or decrease is absorbed by the intake and exhaust of the atmosphere from the communication hole 11b to the internal space 11a.

Even if mist is contained in this atmosphere, the amount of intake and exhaust of this atmosphere is very small considering the size of the internal space 11a (the amount of the lubricant L), and the influence on the cam mechanism is extremely small. Further, by installing a filter for removing mist and the like contained in the atmosphere in the communication hole 11b, this influence can be further reduced. Instead of this, or together with this, a pipe extending from the communication hole 11b to the outside of the processing room (the room in which the tool changing device 10 or the like is installed) may be used to prevent the intrusion of mist or the like.

In this way, the internal space 11a of the housing 11 and the internal space 31b of the arm 30 are communicated with each other by the axial holes 21a, the through holes 21b, and 21c of the arm shaft 21, and the lubricant L can be distributed. As a result, the inflow of outside air or the like into the internal space 31b can be prevented, and the lubricant L that lubricates the cam 17 or the like can be supplied to the arm 30 as well. In this way, by preventing foreign substances from entering the internal space 31b and supplying the lubricant L to the internal space 31b, the life of the lock mechanism (link 35, elastic member 37) of the lock member 33 can be extended. Can be planned.

As shown in FIGS. 3 and 4, the opening / closing member 41 and the cover 42 are arranged at the lower end of the arm shaft 21.

The opening / closing member 41 has a bottomed tubular shape as a whole, has an opening / closing portion main body 411, and a lid portion 412, and opens and closes the through hole 21c (first through hole) of the arm shaft 21. The opening / closing part main body 411 has a substantially cylindrical shape, and has an axial hole 41a and a pair of through holes 41b (second through holes). The through hole 41b penetrates the inner circumference (axial hole 41a) and the outer circumference of the opening / closing portion main body 411. The outer circumference of the opening / closing portion main body 411 corresponds to the inner circumference of the arm shaft 21, and is inserted into the inner circumference of the arm shaft 21. The lid portion 412 has a substantially cylindrical shape and seals the lower end of the arm shaft 21.

Normally, the pair of through holes 41b are arranged so as to face the pair of through holes 21c of the arm shaft 21. In this case, the axial hole 21a and the through hole 21c of the arm shaft 21 are connected through the axial hole 41a and the through hole 41b of the opening / closing main body 411. On the other hand, the opening / closing member 41 can be rotated with respect to the arm shaft 21 so that the through hole 21c of the arm shaft 21 and the through hole 41b of the opening / closing main body 411 do not face each other. At this time, the space between the axial hole 21a and the through hole 21c of the arm shaft 21 is closed by the outer peripheral surface of the opening / closing main body 411.

By rotating the opening / closing member 41 in this way, the communication / non-communication between the through hole 21c (first through hole) and the through hole 41b (second through hole) is switched, and the through hole 21c of the arm shaft 21 is switched. Can be opened and closed.

The cover 42 includes an opening 42a that covers the lid portion 412 but exposes the bottom surface of the lid portion 412. Therefore, with all the members of the arm 30 attached to the arm shaft 21, the bottom surface of the lid 412 is accessed from the opening 42a of the cover 42, the opening / closing member 41 is rotated, and the through hole 21c of the arm shaft 21 is formed. Can be opened and closed. For example, a groove is formed on the bottom surface of the lid portion 412, and a predetermined tool (for example, a screwdriver) can be engaged with the groove to rotate.

The opening / closing member 41 can be used when removing the arm 30 from the arm shaft 21. As described above, the through hole 21c of the arm shaft 21 is usually opened. If the arm 30 is removed from the arm shaft 21 in this state, the lubricant L in the housing 11 may leak from the through hole 21c. That is, before removing the arm 30 from the arm shaft 21, the opening / closing member 41 is rotated to close the through hole 21c, and leakage of the lubricant L at the time of removing the arm 30 (during assembly and maintenance) can be prevented. After closing the through hole 21c, the cover 42 is removed, and the arm 30 is further removed from the arm shaft 21.

[Technical Thought Obtained from the Embodiment]
The technical ideas that can be grasped from each of the above embodiments are described below.

[1] The tool changing device (10) according to the embodiment has a housing (11) in which a first internal space (11a) is formed, and a grip portion (32) for gripping a tool. The arm (30) in which the internal space (31b) of 2 is formed, the lock member (33) for pressing the tool gripped by the grip portion (32), and the arm (30) are connected to each other. A cam mechanism (cam 17, link 18, rotary engaging portion 23, elevating engagement) arranged in the arm shaft (21) and the first internal space (11a) to rotate or elevate the arm shaft (21). A portion 26) and a lock mechanism (link 35, elastic member 37) arranged in the second internal space (31b) and moving the lock member (33) are provided. The housing (11) has a first communication hole (11b) that communicates the first internal space (11a) with the outside, and the arm shaft (21) has the first internal space (11a). ) And the second internal space (31b) have a second communication hole (axial hole 21a). As a result, by communicating the first internal space (11a) and the second internal space (31b), the invasion of foreign matter into the second internal space (31b) is prevented, and the length of the locking mechanism is increased. The life can be extended.

[2] The atmosphere circulates in the first communication hole (11b), and the lubricant (L) circulates in the second communication hole (axial hole 21a). Thereby, the increase / decrease in the amount of the lubricant (L) in the first internal space (11a) can be absorbed.

[3] The second communication hole (axial hole 21a) communicates with the axial hole (21a) formed along the axial direction of the arm shaft (21) and the axial hole (21a). It has a first through hole (21c) that opens on the side surface of the arm shaft (21). The tool changing device (10) further includes an opening / closing member (41) that opens / closes the first through hole (21c). As a result, the opening / closing member (41) closes the first through hole (21c), and the lubricant (L) can be prevented from leaking when the arm (30) is removed.

[4] The opening / closing member (41) has a bottomed tubular member (41) that is rotatably inserted into the axial hole (21a), and the tubular member (41) has a bottomed tubular member (41). A second through hole (41b) penetrating the inside and outside thereof is formed, and by rotating the tubular member (41), the first through hole (21c) and the second through hole (41b) are formed. Communication and non-communication are switched. This facilitates opening and closing of the first through hole (21c).

10 ... Tool changer 11 ... Housing 11a, 31b ... Internal space 11b ... Communication hole 13 ... Motor 14 ... Reduction mechanism 17 ... Cam 18, 35 ... Link 21 ... Arm shaft 21a ... Axial hole 21b, 21c, 31a, 41b ... Through hole 22 ... Cylindrical body 23 ... Rotational engaging part 26 ... Elevating engaging part 30 ... Arm 31 ... Arm body 31c ... Flow path 31d, 42a ... Opening 32 ... Gripping part 33 ... Lock member 34 ... Lock shaft 36 ... Pressing member 37 ... Elastic member 41 ... Opening / closing member 41a ... Axial hole 42 ... Cover

Claims (4)

The housing in which the first internal space is formed and
An arm and an arm that has a grip for gripping the tool and forms a second interior space.
A lock member for pressing the tool gripped by the grip portion and
An arm shaft connected to the arm and
A cam mechanism that is arranged in the first internal space and that rotates or raises and lowers the arm shaft,
It is provided with a lock mechanism that is arranged in the second internal space and moves the lock member.
The housing has a first communication hole that allows the first internal space to communicate with the outside.
The arm shaft is a tool changing device having a second communication hole for communicating the first internal space and the second internal space. The tool changing device according to claim 1.
Atmosphere circulates in the first communication hole.
The second communication hole is a tool changer through which a lubricant flows. The tool changing device according to claim 1 or 2.
The second communication hole is
Axial holes formed along the axial direction of the arm shaft and
It has a first through hole that communicates with the axial hole and opens on the side surface of the arm shaft.
The tool changing device is a tool changing device further comprising an opening / closing member for opening / closing the first through hole. The tool changing device according to claim 3.
The opening / closing member has a bottomed tubular member that is rotatably inserted into the axial hole.
A second through hole that penetrates the inside and outside of the tubular member is formed in the tubular member.
A tool changing device that switches between communication and non-communication between the first through hole and the second through hole by rotating the tubular member.

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