JPS62157756A - Pallet changer - Google Patents

Abstract

PURPOSE:To improve working efficiency, by providing a pallet moving mechanism which is provided at the hook part of a pallet with a disengageable hook, and moves the pallet in an engaged state to and from the table of a machine tool. CONSTITUTION:Plural rotary tables 19, having a guide way 21 guiding a pallet 22 for mounting a work, are rotatably mounted on a turn table 18. Each rotary table 19 is provided with a pallet holding mechanism, enabling the rotary table 19 to be rotated in a state to hold the pallet 22. Further, a pallet moving mechanism 35, having a hook 36 which is engageable with a hook part 33 attached to the pallet 22, and moving the pallet 22, in a hook-engaged state, from the rotary table 19 to the table of a machine tool or reversing above movement of the pallet, is situated on the turn table 18. This constitution enables efficient mounting of the work onto the pallet 22.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a pallet changer that supplies and discharges a balent with a workpiece attached to a table of a machine tool such as a machining center.

[Background technology and its problems]

Conventionally, for the purpose of improving the machining efficiency of machine tools, ? j［
Using pallet B, set up a new workpiece on another pallet while machining the workpiece attached to pallet - with a machine tool, and then set up a new workpiece on another pallet after finishing machining the workpiece on pallet -. A pallet that is ejected from the machine tool and another pre-set up pallet is supplied to the table of the machine tool for processing, and the processed workpiece of the - pallet is replaced with an unprocessed workpiece to continue processing. changer is known.

In such conventional pallet changers, the pallet pedestal on which the pallet is placed is fixedly provided to the frame or swivel base. There is a problem in that it becomes difficult to attach workpieces located on the side, prolonging workpiece exchange time, and hindering improvement in the work efficiency of the machine tool.

[Purpose of the invention]

SUMMARY OF THE INVENTION The present invention provides a pallet changer that can highly efficiently set up a plurality of workpieces onto pallets on the pallet changer.

[Means and effects for solving the problems] The present invention has the following features:
A rotating table is rotatably supported on the frame, and a plurality of rotating tables are rotatably provided on the rotating table, each having a guideway for guiding a pallet for mounting a workpiece. A pallet holding mechanism is provided that allows the rotating table to rotate while holding the pallet, and further includes a hook that is removable from a hook provided on the pallet and that engages with the hook. The present invention is characterized in that a pallet moving mechanism is provided on the rotating table to move the pallet from the rotating table to the table of the machine tool or vice versa.

With this configuration, it is possible to attach a plurality of workpieces to the pallet in sequence while rotating the pallet together with the rotary table on the revolving table, thereby achieving the above object.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on the drawings.

In FIGS. 1 and 2 showing the overall configuration, a pivot shaft 13 is rotatably supported on the frame 11 via a bearing 12, and a support shaft 14 is inserted into the axis of the pivot shaft 13 so as to be relatively rotatable. has been done.

This support shaft 14 is connected to the frame 1 via a bracket 15.
1 is supported. A gear 16 is fixed to the outer periphery of the lower part of the pivot shaft 13, and a rack 17 is meshed with the gear 16. When the rack 17 is moved in a direction perpendicular to the paper plane in FIG. It is designed to rotate together with the gear 16.

A turning table 18 is fixed to the upper end of the turning shaft 13, and a rotating table 19 is rotatably provided at two places on the left and right sides of the upper surface of the turning table 18.

A cover 20 is attached to the top surface of the rotary table 19, and a guideway 21 consisting of a plurality of rollers is provided on both sides of the rotary table. pallets 22 can be guided onto the rotating table 19. Further, a center shaft 23 is supported substantially at the center of the rotary table 19 so as to be movable in the axial direction, that is, in the vertical direction, and a spring 24 is interposed between the lower part of the center shaft 23 and the rotary table 19. 23 is always biased upward. The upper end of this center shaft 23 passes through the cover 20 and connects to the pallet 22.
The center shaft 23 is normally engaged with the engagement hole 25 formed in the lower central part of the center shaft 23 by the action of the spring 24.

Further, a horizontal hole 26 is formed in the middle of the center shaft 23 , and a spherical tip of a swing shaft 27 is engaged with the horizontal hole 26 . It is swingably supported by the rotating table 19. The other end of the swing shaft 27 extends to the outside of the rotating table 19, and a cam follower 29 is provided at this outer position, and the cam follower 29 is engageable with a cam 30 provided on the rotating table 18. When this is done, the swing shaft 27 is swung so that the spherical tip faces downward as shown in FIG. The center shaft 23 is moved downward against the spring 24.
The upper end of the barre 7) can be disengaged from the engagement hole 25 of the barre 7) 23.

Therefore, the upper end of the center shaft 23 is connected to the engagement hole 2 of the pallet 22.
5, the pallet 22 is removed from the rotating table 19.
The table 3 of a machine tool such as a machining center is movable along the guideway 21 in the left and right directions in FIG.
It can be transferred onto 1. On the other hand, when the upper end of the center shaft 23 is engaged with the engagement hole 25, the rotation table 1 of the pallet 22 positioned on the rotation table 19 due to this engagement.
The position on the guideway 21 is maintained, and the pallet 22 is prevented from moving along the guideway 21. Further, the cam 30 is provided only at a position where it engages with the cam follower 29 of the swing shaft 27 when the rotary table 19 is located at a predetermined angular position, that is, the position where the pallet 22 is transferred to the table 31. When the cam 30 and the cam follower 29 are rotated to other positions, the cam 30 and the cam follower 29 do not engage with each other, so that the upper end of the center shaft 23 is engaged with the engagement hole 25 of the pallet 22. . put it here,
The center shaft 23, the spring 24, the engagement hole 25 of the pallet 22, the swing shaft 27, the bearing 28, the cam follower 29, and the cam 30 constitute a pallet holding mechanism 32.

On the sides of the two pallets 22 facing the raw tiles shown in FIG. A hook 36 is lockable.

The hook 36 has a downward groove that engages with the hook 33, and the shape of the downward groove is such that the pallet 22 can be moved in the left-right direction in FIG. 1 while engaged with the hook 33. It is said that Two sets of pallet moving mechanisms 35 are provided so that each pallet 22 can be moved independently, and the detailed structure thereof is shown in FIGS. 3 to 6. In these figures, the hook 36 is pivotally supported at its base end by a box-shaped portion of a swinging arm 37 whose upper portion is formed into a box-shape so that it can pivot in a horizontal plane, and the hook 36 and the swinging arm 3
7, a hook return spring 39 made of a compression coil spring is interposed via a spring receiver 38 having a spherical bearing. As a result, the hook 36 is biased clockwise in FIG.
It is maintained at a position where it can be engaged with the hook portion 33 of the. The swinging arm 37 has a bearing portion projecting downward and is rotatably supported by the upper bifurcated portion 40A of the movable table 40 via a shaft 41, so that the hook 36 can be moved vertically about the shaft 41. It is possible to swivel.

A swing arm return spring 41A is interposed between the lower part of the movable arm 37 and the upper part of the movable base 40, and the movable arm 37 and the movable base 40 are connected by bolts 41B, and the swing arm 41A is connected to the movable arm 37 by a bolt 41B. Rotation of the movable arm 37 is restricted.

As a result, the movable arm 37, ie, the hook 36, is held in a substantially horizontal position.

The movable table 40 is supported so as to be movable in the horizontal direction in FIG. 5 along a guide 42 provided on the side surface of the turning table 18, and holds a ball shaft 43 at its lower part. This ball nut 43 is screwed into a ball screw 44, and this ball screw 44 is rotationally driven by a motor 45 attached to the turning table 18. Therefore, by driving the motor 45, the movable table 40 is moved in the left-right direction in FIG. 5 along the guide 42 via the ball screw 44 and the ball nut 43. Further, a hole is provided on the outer periphery of the portion of the movable table 40 that supports the pole napft 43.

A dog 46 for detecting advance/retreat is provided, and when this dog 46 comes into contact with a limit switch (not shown), the advance or retreat limit of the movable platform 40 is detected, and the motor 45 is stopped.

At this time, the advancing limit and the retreating limit of the moving table 40 are the transfer position of the pallet 22, which is moved via the hook 36 and the hook 33 as the moving table 40 moves, onto the table 31 of the machine tool and the rotary table, respectively. 19 is the transfer position. Here, the pallet moving mechanism 35 is composed of members having a series of part numbers from the hook 36 to the hook advance/retreat detecting dog 46. Note that the reference numeral 47 in FIG.
It is a cover provided to cover a part of the

FIG. 7 shows the detailed structure of the gear 16 and rack 17 attached to the lower part of the pivot shaft 13 described in FIG. 1. In this figure, the hook 1
7 is a guide block 48 attached to the frame 11
The guide block 48 is supported so as to be movable in the axial direction, and is driven in the axial direction by a cylinder 49 attached to the guide block 48. Further, a pair of dogs 50 and 51 are provided at the tip of the rack 17, and the dog 51 at the tip can come into contact with a limit switch 52 for detecting the extension limit, and the inner dog 51 is for detecting the rearward limit. The cylinder 49 can be brought into contact with the limit switch 53, and the movement of the cylinder 49 can be controlled. Here, gear 16, rack 17, guide protector 48, cylinder 49, dog 50.51 and limit switch 5
2.degree. 53 constitutes a turning drive mechanism 54 for the turning table 18.

In FIG. 1, a rotary table locking shaft 57 is supported on both sides of the rotating table 18 via brackets 56 so as to be able to move up and down, and this locking shaft 57 has a grip 58 in the middle. A spring 59 is interposed between the bracket 56 and the locking shaft 57! ,L;
At +'i, it is biased upward in the figure. In addition, the locking shaft 57
The upper end portion protrudes through the top plate of the rotating table 18, and is provided at multiple locations on the lower surface of the rotating table 19, i.e., 9 in this embodiment.
It can be fitted into four engagement holes 60 provided at 0 degree intervals. Of these engagement holes 60, the depth of the engagement hole 60 in which the tip of the locking shaft 57 is engaged when each rotary table 19 is in the state shown in FIG. It is formed deeper than the depth of the hole 60, and the locking shaft 57 is held by the spring 59.
It is now possible to rise higher. Accordingly, a dog 61 for detecting the position of the rotary table provided at the lower end of the locking shaft 57 also rises, and this dog 61 acts on a limit switch (not shown) to bring the rotary table 19 to the position shown in the figure. It is possible to detect this. This limit switch is used to detect whether or not the motor 45 of the pallet moving mechanism 35 can be driven, and the motor 45 can only be driven when this limit switch is activated.

Next, the operation of this embodiment will be explained.

In the work start state, empty pallets 22 are placed on each rotating table 19 on the rotating table 18, and the hooks 33 of these pallets 22 are attached to the rotating table 18.
hook 36 of the pallet moving mechanism 35
are engaged with each other. Therefore, the turntable 19
The cam follower 29 of the swing shaft 27 is swingably supported on the
are respectively engaged with the cams 30, so that the spherical tip of the swing shaft 27 is lowered downward, and the center shaft 23 is pushed downward against the spring 24.

Therefore, the center shaft 23 is disengaged from the engagement hole 25 of the pallet 22, and the pallet 22 is made movable on the rotary table 19 along the guideway 21. However, in this state, since the hook portion 33 of the pallet 22 is engaged with the hook 36, the movement of the pallet 22 is prevented and the stopped state is maintained.

Further, at this time, since the rotating table locking shaft 57 is engaged with the engaging hole 60 of the rotating table 19, rotation of the rotating table 19 is also prevented.

In this state, one workpiece is mounted on each of the four sides of the pallet 22 on the right side of the pallet 22 located away from the table 31 of the machine tool in FIGS. 1 and 2. This attachment is carried out after attaching the workpiece to one side of the pallet 22, and then
is manually pulled down against the spring 59 to release the engagement between the locking shaft 57 and the rotary table 19, and manually rotates the rotary table 19 90 degrees at a time. This is done by engaging the shaft 57 and the engagement hole 60. On this occasion,
As the pallet 22 rotates, the hook portion 33 and the hook 36 are disengaged. However, since the swing shaft 27 is also rotated as the pallet 22, that is, the rotating table 19, is rotated, the cam follower 29 of the swing shaft 27 is moved to the cam 30. The center shaft 23 rises due to the action of the spring 24 and the tip of the center shaft 23 engages with the engagement hole 25 formed in the center of the lower surface of the pallet 22 to prevent the pallet 22 from moving. is prevented from falling off the rotary table 19.

When the installation of the four workpieces is completed while rotating the pallet 22 by 90 degrees in this way, the pallet 22
The hook portion 33 provided on the hook portion 33 rotates once and is again engaged with the hook 36, and this engagement is performed as follows. That is, when the hook portion 33 is rotated as the pallet 22 rotates, the hook portion 33 contacts the hook 36 and rotates the hook 36 counterclockwise in FIG. 6 against the hook return spring 39. When the groove formed on the lower surface of the hook 36 is rotated to a position where it can be held on the hook portion 33 by this rotation, the two are engaged and the hook 36 is returned to the old position by the biasing force of the spring 39. 36 and the hook portion 33 are properly secured, and the pallet 22 becomes movable by the hook 36. In addition, in this state, the rotary table locking shaft 57 is engaged with the deepest engagement hole 60 of the rotary table 19, so that
The dog 61 activates the limit switch, and in this state the motor 45 of the pallet moving mechanism 35 can be driven.

When the mounting of the work onto the right pallet 22 is completed, the cylinder 49 of the rotation drive mechanism 54 is activated, and the rotation table 18 is rotated 180 degrees via the hook 17, the gear 16, and the rotation shaft 13.

As a result, the pallet 22 on the right side with the workpiece attached
is located on the left side, facing the table 31, while the empty pallet 22, located on the left side, is located on the right side. Next, when the motor 45 of the pallet moving mechanism 35 is driven and the ball screw 44' is rotated, the moving table 40 is moved to the left in FIG. 1 via the ball nut 43, and the swing arm 37, hook 36, The pallet 33 is moved onto the table 31 via the hook portion 33. Palette 2
When the movement of the pallet 2 onto the table 31 is completed, the pallet 22 is fixed to the table 31 by a locking mechanism (not shown), and then the table 31 is slightly lowered and the hook portion 3
3 and the hook 36 are now in a disengaged state. In this state, the motor 45 is driven in the opposite direction and the pallet moving mechanism 35
will return in the opposite direction to that described above, in an empty state without the pallet 22.

The pallet 22 with the workpieces transferred onto the table 31 in this manner is sequentially processed in a predetermined manner by a machine tool. On the other hand, a new workpiece is attached to the empty pallet 22, which has been newly positioned on the right side as the turning table 18 rotates, while being turned by 90 degrees in the same manner as described above, and is prepared for the next processing.

Next, when the machining of the workpiece is completed by the machine tool, the motor 45 of the empty pallet moving mechanism 35 is driven to move the hook 36 to the table 31 side, and the pallet 2 is moved again.
The hook 36 is engaged with the hook portion 33 of No. 2. At the time of this engagement, the hook 36 passes over the upper end of the hook portion 33 and is engaged. This climbing over the hook portion 33 of the hook 36 is performed by the swing arm 37 swinging upward against the swing arm return spring 41A. In this way hook 36
When the hook portion 33 is engaged with the pallet 22 , the fixation of the pallet 22 to the table 31 is released, the motor 45 is driven in the opposite direction again, and the pallet 22 is transferred onto the rotary table 19 . Completion of the transfer of the pallet 22 onto the rotating table 19 is detected by a hook advance/retreat detecting dong 46 provided at the lower part of the moving table 40 and a limit switch (not shown).

When the pallet 22 with the finished workpiece attached in this way is transferred onto the rotary table 19, the cylinder 49 of the swing drive mechanism 54 is driven in the opposite direction to the above-mentioned direction.
The turning table 18 is turned 180 degrees in the opposite direction, and the pallet 22, on which a new workpiece has been previously attached, is positioned on the table 31 side while the workpiece is being processed by the machine tool.
On the other hand, the pallet to which the processed workpiece is attached will be located on the right side. In this state, the pallet 22 to which the unprocessed workpiece is attached is supplied to the table 31 in the same manner as described above, while the pallet 22 to which the processed workpiece is attached is replaced with a new workpiece. be exposed.

Thereafter, the workpiece machining operation is continued by sequentially repeating the above-described operations.

According to this embodiment as described above, since the rotating table 19 provided on the rotating table 18 is made rotatable, it is not necessary to attach the workpieces to the pallet 22 in a narrow position close to the machine tool side. This can be done sequentially in a large open space, and workpiece replacement efficiency can be significantly improved.

Further, while the pallet 22 can be easily transferred to the rotating table 19 by the guideway 22, the pallet 22 can be prevented from falling off from the rotating table 19 by the pallet holding mechanism 32 and the piece part 3.
3 and the hook 36, and there is no hindrance to the movement of the pallet by the pallet moving mechanism 35, so a series of pallet exchange operations can be carried out smoothly. Furthermore, the hook portion 3 of the pallet 22
Since the hook 33 to be engaged with the hook 33 is pivotable in a horizontal plane and vertically pivotable via the swing arm 37, the hook 33 and the hook 36 can be engaged automatically. . Further, since the pallet moving mechanism 35 uses a ball screw 44 driven by a motor 45 and a ball nut 43 screwed into the ball screw 44, the pallet 22 can be moved smoothly and accurately.

In the above embodiment, the motor 45, the ball screw 44, and the ball nut 43 were used as the drive structure for the pallet moving mechanism 35, but the present invention is not limited thereto, and a structure using a cylinder or the like may be used. but,
If the above embodiment is used, the hook advance/retreat detecting dog 46
By appropriately setting the positional relationship between the pallet 22 and a limit switch (not shown), it is advantageous that the feed amount of the pallet 22 and the like can be adjusted in relation to the table 31 of the machine tool.

On the other hand, the rotation drive mechanism 54 may also be one using a motor or the like instead of the cylinder 49, but in the case of this rotation drive mechanism 54, it is sufficient to always rotate the rotation table 18 by 180 degrees in forward and reverse directions. Therefore, it is more advantageous to use the cylinder 49, which is cheaper. Further, the structure of the pallet holding mechanism 32) rotary table locking shaft 57 is not limited to the structure of the above embodiment, but may be any other mechanism that can achieve the same function.
The structure of the embodiment described above has the advantage that it can achieve the intended purpose with a relatively FJ ja configuration and can be provided at low cost.

Furthermore, the number of turntables 19 for rotating the pallets 22 is not limited to two, but may be three or more.

〔Effect of the invention〕

As described above, according to the present invention, there is an effect that workpieces can be efficiently mounted on the pallet 22.

[Brief explanation of drawings]

Fig. 1 is a partially sectional front view showing an embodiment of the present invention, Fig. 2 is a plan view thereof, Fig. 3 is a perspective view of the pallet moving mechanism in this embodiment, and Fig. 4 is a front view thereof. , Fig. 5 is a side view thereof, Fig. 6 is a plan view of its swing arm, and Fig. 7 is a side view thereof.
The figure is a sectional view of the swing drive mechanism taken along the line ■-■ in FIG. 1. 11... Frame, 18... Rotating table, 19.
... Turntable, 21... Guideway, 22... Valent, 23... Center axis, 24... Spring, 3
1... Table, 32... Pallet holding mechanism, 33
...Hook portion, 35...Pallet moving mechanism, 36...
Hook, 37... Swinging arm, 40... Moving platform, 4
3... Ball nut, 44... Ball screw, 45...
··motor.

Claims (4)

[Claims] (1) A turning table rotatably supported by a frame, a plurality of turntables each rotatably provided on the turntable and having a guideway for guiding a workpiece mounting pallet, and each of these turntables a pallet holding mechanism that is provided on the rotating table and is provided on the pallet; a pallet holding mechanism that is provided on the rotating table and is provided on the pallet; A pallet changer characterized by having a hook that can be engaged with and detached from a hook portion, and a pallet moving mechanism that moves a pallet from a rotary table to a table of a machine tool or vice versa when the hook is engaged. (2) The pallet changer according to claim 1, wherein the hook of the pallet moving mechanism is configured to be pivotable in the vertical direction and in a horizontal plane. (3) In claim 1 or 2, the pallet moving mechanism is configured such that the hook can be moved by a motor-driven ball screw and a ball nut screwed onto the ball screw. A palette changer characterized by: (4) In any one of claims 1 to 3, the pallet holding mechanism is provided so as to be projectable and retractable in the center of the rotary table, and is normally provided in the center of the pallet by a spring. a center shaft biased to engage with the engagement hole; one end side of the center shaft is engaged with the center shaft, and the center shaft is swingably supported by a rotary table;
and a swing shaft whose other end is engageable with a cam provided on the revolving table, and when engaged with the cam, resists the spring and causes the center shaft to escape from the engagement hole of the pallet. A palette changer that features: