JPH0131413Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a positioning device used in a pallet changer for a machining center, etc.

Generally, a machining center MC is connected with an automatic pallet changer APC and a setup station PS as shown in Fig. 1, and when a pallet carrier 1 carrying a pallet P1 is indexed and positioned on the machining center MC side, The pallet carrier 2 carrying the pallet P2 is configured to be indexed to the position of the setup station PS. In the normal state, as shown in FIG. 2, the pallet guide 4 fixed to the pallet carrier 3, the pallet transport guide 6 fixed to the base 5 of the setup station PS, and the setup table Since the fixed guides 8 are aligned in a straight line, the pallet P2 is carried from the pallet carrier 3 to the setup station PS by a linear movement.

However, if a misalignment occurs between the pallet carrier 3 and the setup station PS, a misalignment will occur between the guide 4 and the guides 6 and 8 as shown by the two-dot chain line in FIG. , 6 and 8, the pallet comes into contact with the end face of the guide 6 and cannot be transported.

Therefore, at present, the end faces of the guides 4, 6, and 8 are tapered to allow some degree of deviation, but especially in those that use a conveyor chain to drive the pallet carrier, the end faces of the guides 4, 6, and 8 are tapered, but this is especially true when a conveyor chain is used to drive the pallet carrier. At the same time, there is a drawback that the conveyor chain is elongated, and the shift cannot be absorbed only by processing the end faces of the guides 4, 6, and 8.

The misalignment of the pallet carrier 3 is caused by the fact that the conveyor chain has variations in the length direction and is wound endlessly around the outer circumference of the rail and is driven by a sprocket. Therefore, it is caused by the influence of inertial load of each pallet carrier, running resistance, etc.

The present invention provides a positioning device for simultaneously positioning at least two pallet carriers at different positions by transporting a plurality of pallet carriers using a conveyor chain arranged in an annular manner. The eccentric shaft portions of drive pin shafts whose rotation can be adjusted within the conveyance plane of the pallet carrier are engaged with the locking grooves of the joint blocks provided on the conveyor chain, and are connected to the conveyor chain respectively. A stopper is disposed in the movement path of each joint block so as to be able to appear and retract freely, and a stopper is provided in each of the above-mentioned joint blocks to contact one stopper protruding into the movement path of the joint block so that the joint block can move all together with the conveyor chain. The stopper bolt that stops the pallet carrier is adjustable in the axial direction.
The object is to provide a positioning device that can accurately and easily adjust the mutual positional deviation of a plurality of pallet carriers that are simultaneously positioned at predetermined positions.
Hereinafter, the present invention will be specifically explained with reference to the drawings.

Figures 3 to 5 show an embodiment of the present invention, and the reference numeral 10 in the figures is a conveyor chain, which is stretched outside the rails 11 of an automatic pallet changer. . The conveyor chain 10 is configured to move along a rail 11 by means of a sprocket 12. Further, a joint block 13 is provided on the conveyor chain 10 so as to protrude outward, and a stopper bolt 14 is inserted through the joint block 13 to connect the conveyor chain 1.
The locking groove 15 is attached in the direction along the axis 0, is adjustable in the axial direction, and is formed with a locking groove 15 that opens outward. An eccentric shaft portion 17a of a drive pin shaft 17 provided on the pallet carrier 16 is fitted into this locking groove 15. The root end 17b of the drive pin shaft 17 is provided with a pair of arc-shaped holes 17c centered on the axis Z of the drive pin shaft.
A bolt is inserted through each of the pins 7c to fix the drive pin shaft 17 to the pallet carrier 16. Therefore, with the bolt loosened, the root end 17b of the drive pin shaft 17 is rotated as appropriate within the range of the circular arc of the hole 17c around the axis Z, and the drive pin shaft 17 is attached to the pallet carrier 16. The relative mounting position between the axis Z of the pin shaft 17 and the conveyor chain 10 is determined by the eccentric shaft portion 17.
It is configured to be continuously adjustable by twice (2ε) the amount of eccentricity ε of a. Further, the tip of the stopper bolt 14 (the end on the moving direction side of the conveyor chain) is configured so that the pallet carrier 16 comes into contact with a stopper 18 protruding into the movement path of the joint block 13 and stops when positioning.

Next, the operation of the positioning device configured as described above will be explained with reference to FIG. 6.

The conveyor chain 10 is stretched around the outer periphery of the rail 11 as tightly as possible, and the sprocket 12
The conveyor chain 1 is driven clockwise by
Stopper 18 protruding outward from the movement path of 0
By the stopper bolt 14 coming into contact with
On the machining center side (right side in Fig. 6), the eccentric shaft portion 17a (joint block 13) of the pallet carrier 16' stops at a position advanced by an angle α in the moving direction of the conveyor chain 10 from the longitudinal center line x of the pallet changer. , which is the predetermined indexing position of the pallet carrier 16'. At this time,
If the stopping angle of the joint block 13 of the pallet carrier 16'' on the setup station side (left side in Figure 6) is α', then the conveyor chain 10
The angle of deviation of the pallet chain from the longitudinal center line The difference from the stopping angle α of block 13, that is, α'-α=β. Therefore, the stopper bolt 14 is projected toward the stopper 18, and the conveyor chain 10 on the machining center side is rotated counterclockwise by an angle β. Then, the drive pin shaft 17 on the machining center side also moves counterclockwise by an angle β.
Loosen the bolt fixing the drive pin shaft 17 to the pallet carrier 16', rotate the drive pin shaft 17 around its axis, move the eccentric shaft portion 17a in the direction of movement of the conveyor chain 10, and move it to the machining center side. By returning the pallet carrier 16' clockwise by the angle β, the pallet carrier 16' on the machining center side can be returned to the position at the angle α. As a result, the pallet carriers 16', 16'' can be properly positioned and adjusted on both the machining center side and the setup station side without any deviation.

When the above adjustment is completed, turn the conveyor chain 10 clockwise as shown in Fig. 6 to move the right pallet carrier 16' to the left side and the left pallet carrier 16'' to the right side, and make the same adjustment as above. , the two pallet carriers that are related to each other are connected generally and substantially at intermediate positions of the conveyor chain 10, so that finally both pallet carriers fall within the permissible range. 17, the positional deviation can be corrected by adjusting the conveyor chain 10 in a predetermined state. Palette carrier 1 on the right while facing it
Since the position of 6' can be corrected again, the positioning can be adjusted more accurately. In addition, the eccentric shaft portion 17
If the amount of deviation is larger than the amount equivalent to twice the eccentricity ε of a, adjustment will not be possible, but normally the tolerance in the length direction of the conveyor chain 10 can be kept to +0.5% -0%. Considering the specifications of the automatic pallet chainer currently in use, eccentricity = 1/2 (conveyor chain length x 1/2 ÷ 0.5%) = 1/2 (1400 x 12 x 1/2 x 0.5/100) = 21 mm, and in practice, it is easy to manufacture the drive pin shaft 17 having the eccentric shaft portion 17a with the above eccentricity. In addition, if the influence of inertial load force F due to loosening of the conveyor chain, which is one of the causes of positional deviation, cannot be ignored, as shown in FIG. In this case, it is preferable to provide a guide 20 on the rail 11 at the position where each pallet carrier stops, as shown in FIGS. 8 and 9.

As described above, the positioning device of the present invention is a positioning device that simultaneously positions at least two pallet carriers at different positions by transporting a plurality of pallet carriers using a conveyor chain arranged in an annular manner. Each pallet carrier engages an eccentric shaft portion of a drive pin shaft whose rotation can be adjusted within the conveying plane of the pallet carrier in a locking groove of a joint block that protrudes outside the conveyor chain and is provided on the conveyor chain. The joint blocks are connected together to the conveyor chain, and a stopper is provided in the movement path of each of the joint blocks so as to be freely retractable. Since the stopper bolt that contacts one stopper and stops all the pallet carriers together with the conveyor chain is provided so as to be freely adjustable in the axial direction, the drive can be adjusted by rotating the drive pin shaft. By moving the eccentric shaft portion of the pin shaft in the length direction of the conveyor chain, the engagement positional relationship between the conveyor chain and the pallet carriers is changed, and at the same time, the positional deviation between the plurality of pallet carriers each positioned at a predetermined position is corrected. It has the excellent effect of comprehensively or substantially absorbing the effects of elongation of the pallet carrier, inertial load, running resistance, etc., and making adjustments and corrections extremely easy.

[Brief explanation of the drawing]

Figs. 1 and 2 are plan views of a conventional automatic pallet changer, Figs. 3 to 5 show an embodiment of the present invention, Fig. 3 is a plan view, and Fig. 4 is a drive pin. A perspective view of the shaft, FIG. 5 is an explanatory diagram showing the amount of eccentricity, FIG. 6 is a configuration diagram showing the operation of the positioning device according to the present invention, FIG. 7 is an explanatory diagram showing the state of a conventional conveyor chain, and FIG. 9 and 9 show another embodiment of the present invention, with FIG. 8 being a sectional view and FIG. 9 being a plan view. 10...Conveyor chain, 13...Joint block, 14...Stopper bolt, 15...
Locking groove, 16... Pallet carrier, 17... Drive pin shaft, 18... Stopper, 17a... Eccentric shaft portion.

Claims (1)

[Scope of utility model registration request] A positioning device that simultaneously positions at least two pallet carriers 16 at different positions by transporting a plurality of pallet carriers 16 using a conveyor chain 10 arranged in an annular manner,
Each of the pallet carriers 16 has a drive pin that protrudes outside the conveyor chain 10 and is installed in a locking groove 15 of a joint block 13 provided on the conveyor chain 10, and is rotatably adjustable within the conveyance plane of the pallet carrier 16. The eccentric shaft portions 17a of the shafts 17 are engaged with each other and connected to the conveyor chain 10, and stoppers 18 are disposed in the movement paths of the joint blocks 13 so as to be retractable. , a stopper bolt 14 is provided which is adjustable in the axial direction and stops all the pallet carriers 16 together with the conveyor chain 10 by coming into contact with one stopper 18 protruding into the movement path of the joint block 13. Characteristic positioning device.