JP4501089B2 - Transport device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a ceiling arrangement type transfer device used in a transfer device, particularly a clean room of a factory.
[0002]
[Prior art]
An example of this type of transport device is shown in FIGS. In this transport device, a rail 1 is installed above a work space of a factory or a warehouse, for example, along a transport path near the ceiling, and the travel device 2 is traveled by the travel drive mechanism 3 along the rail 1. is there. A lifting device 4 is mounted on the traveling device 2, and the lifting device 4 suspends and supports the work holding device 6 by four belts 5, and lifts and lowers the work holding device 6 by winding and feeding the belt 5. Has been.
[0003]
As shown in FIG. 3, the lifting / lowering device 4 is configured to wind the belts 5 around the drums 7, and the drums 7 are rotated in synchronization with a motor (not shown) and the amount of rotation is controlled uniformly. Thus, each belt 5 is evenly wound or fed out so that the work holding device 6 is always moved up and down while maintaining the horizontal posture.
[0004]
[Problems to be solved by the invention]
By the way, although the thickness of the belt 5 that suspends and supports the workpiece holding device 6 in the transport device having the above configuration is about 1 mm, the thicknesses of the four belts 5 are slightly different, or initially, Even if they are equal, it is assumed that the thickness of each belt 5 will have a subtle difference due to the change in wear. In such a case, even if the amount of rotation of each drum 7 is equal, a difference occurs in the state of thickening of the belt 5 on each drum 7, so that a difference occurs in the winding amount and feeding amount of each belt 5. become. In addition, since the winding torque of the belt 5 by the drum 7 changes according to the winding thickness, it is difficult to maintain the horizontal posture of the work holding device 6 with the conventional conveying device. An unexpected situation such as the occurrence of
[0005]
In view of the above circumstances, the present invention provides a transport device that can accurately control the lifting and lowering of the workpiece holding device without being affected by the thickness of the belt and without changing the winding torque.
[0006]
[Means for Solving the Problems]
The conveying device of the present invention includes a traveling device that moves along a track, a work holding device that is suspended and supported from the traveling device by a timing belt, and a lifting device that is mounted on the traveling device and raises and lowers the work holding device. The lifting device includes a plurality of timing belts, a plurality of pulleys that pulls and pulls down the timing belts in a non-slip state by rotating while holding the timing belts, and a motor that rotationally drives the plurality of pulleys. A plurality of winding rollers that rotate in accordance with the pulling-up and pulling-down operation of the timing belt by the pulley, and winds and feeds the base end portion of the timing belt ; power from the motor; and the plurality of pulleys and the plurality of pulleys A power transmission mechanism for transmitting to the take-up roller, the power transmission mechanism and the plurality of It and a plurality of clutches for connecting the can up roller consists toothed belt having teeth formed on the contact surface between the timing belt the pulley, toothed said pulley to mesh with the toothed belt made from the pulley, the rotational driving force of the motor is transmitted to each of the take-up roller via the power transmission mechanism and the clutch, the take-up roller and configured to rotate allowed driven to the pulley, the clutch Is a winding speed of the timing belt by the winding roller so that when the timing belt is pulled up by the pulley, only the portion of the timing belt pulled up by the pulley is wound up by the winding roller. Will exceed the pulling speed of the timing belt by the pulley When the timing belt is pulled down by the pulley, when the timing belt is pulled down by the pulley, the winding of the winding roller is fed out from the winding roller by the amount that the timing belt is pulled down by the pulley. The roller is idled .
[0007]
The lifting device in the conveying device of the present invention does not lift and lower the work holding device by directly winding and feeding the belt with a drum as in the conventional device, but the desired stroke while always holding the timing belt with a pulley. The work holding device is lifted and lowered only by lifting and lowering. Then, the timing belt is pulled up and pulled out by following the pulling-up and pulling-down operations of the timing belt and the winding roller driven to rotate. In this case, the take-up roller takes up the timing belt by the amount pulled up by the pulley and feeds the timing belt by the amount pulled down by the pulley. Therefore, the amount of pulling up and feeding out the timing belt by the pulley can be controlled regardless of the amount of winding and feeding by the winding roller, and is not affected by the thickness of the timing belt. Further, the pulling torque by the pulley is always constant without being influenced by the winding torque by the winding roller. Further, in order to cause the take-up roller to be driven by the pulley and rotate, the rotational driving force of the pulley driving motor is transmitted to the take-up roller via the power transmission mechanism and the clutch.
[0008]
As a configuration for pulling up and down while always holding the timing belt by the pulley, for example, a toothed belt having teeth formed on the contact surface with the pulley is used as the timing belt, and the pulley meshes with the toothed belt. It is conceivable to use a toothed pulley .
[0010]
DETAILED DESCRIPTION OF THE INVENTION
1 and 2 show an embodiment of the present invention. The transfer device of this embodiment is equipped with a lifting device 10 on a traveling device 2 that travels along a rail 1 (see FIG. 3) as in the conventional device shown in FIG. 6 (see FIG. 3) is configured to be suspended and supported, and the configuration of the lifting device 10 is different from that of the conventional lifting device 4.
[0011]
FIG. 1 is a plan view showing a schematic configuration of an elevating device 10 in a transport device of the present embodiment, FIG. 2 is a side sectional view, reference numeral 11 is four timing belts that support and support a work holding device 6, and 12 Is a pulley for raising and lowering each timing belt 11, 13 and 14 are pinch rollers for pressing the timing belt 11 against the pulley 12, and 15 is a guide roller. Reference numeral 16 denotes a motor for rotationally driving the pulley 12, and the driving force is transmitted to each pulley 12 by a series of power transmission mechanisms constituted by a gear 17 and a rotating shaft 18, thereby driving the motor 16. Thus, the pulleys 12 are configured to rotate simultaneously in synchronism.
[0012]
The timing belt 11 is a toothed belt in which teeth are formed on the contact surface with the pulley 12, and the pulley 12 is a toothed pulley having teeth that mesh with the teeth of the timing belt 11. By rotating the pulley 12 by driving the motor 16 in a state where the timing belt 11 is sandwiched between the pinch rollers 13 and 14 and the pulley 12, the timing belt 11 is always held by the pulley 12 and the pulley 12. Therefore, it can be reliably lifted and lowered without slipping.
[0013]
Further, the take-up roller 20 is driven to rotate following the pulling-up / down operation of the timing belt 11 by the pulley 12 so that the base end portion of the timing belt 11 is taken up and fed out. That is, a take-up roller 20 that winds up the proximal end portion of the timing belt 11 is disposed at a position adjacent to each pulley 12, and a rotary shaft 22 is connected to the take-up roller 20 via a clutch 21. A belt 23 serving as a power transmission mechanism is wound between the shaft 22 and the rotating shaft 18 that rotationally drives the pulley 12. When the motor 16 rotates the pulley 12 to raise or lower the timing belt 11. At the same time, the take-up roller 20 also rotates to take up or feed out the timing belt 11. However, the winding and unwinding of the timing belt 11 by the winding roller 20 needs to be driven by the pulling and pulling-down operation of the timing belt 11 by the pulley 12 only. Therefore, the rotation of the winding roller 20 is limited by the clutch 21. The part pulled up by the pulley 12 is wound up, and the part pulled down by the pulley 12 is fed out.
[0014]
That is, when the pulley 12 and the take-up roller 20 are rotated together to take up the timing belt 11 while taking up the timing belt 11, the take-up speed is constant by the pulley 12, but the take-up roller 20 gradually becomes thicker. The winding speed by is gradually increased. If the take-up speed by the take-up roller 20 becomes higher than the pull-up speed by the pulley 12, the take-up speed by the take-up roller 20 is prioritized over the pull-up speed by the pulley 12. become. Therefore, in order to prevent such a situation, the clutch 21 begins to slip when the winding speed of the winding roller 20 exceeds the pulling speed of the pulley 12, and the rotation of the winding roller 20 is restricted. High-speed winding is naturally avoided. When the pulley 12 pulls down the timing belt 11, the take-up roller 20 is automatically idled so that only the pull-down amount is paid out, so that the pay-out amount from the take-up roller 20 is set by the pulley 12. It can be avoided that the timing belt 11 is loosened by exceeding the pulling amount, or that the take-up roller 20 restrains the pulling operation of the pulley 12.
[0015]
The elevating device 10 having the above-described configuration raises and lowers the timing belt 11 by a desired stroke while holding the timing belt 11 with the pulley 12, and then follows the lifting and lowering operation by the pulley 12 to rotate the winding roller 20 to follow the timing belt 11. Is pulled up by the amount pulled up by the pulley 12 and is fed out by the amount pulled down by the pulley 12, the amount by which the timing belt 11 is pulled up by the pulley 12 and the amount by which the timing belt 11 is drawn by the winding roller 20 is wound. Control is possible regardless of the amount of pick-up and the amount of feed. The pulling torque by the pulley 12 is always constant regardless of the winding torque by the winding roller 20. Therefore, as in the conventional lifting device 4 that lifts and lowers the work holding device 6 by winding and unwinding the belt 5 by controlling the rotation amount of the drum 7, the winding amount is influenced by the thickness of the belt 5. The feeding amount does not change, and the winding torque does not change due to thickening.
[0016]
Therefore, in the transport device of the present embodiment provided with the lifting device 10 described above, even if there is a difference in the thickness of the four timing belts 11, the lifting stroke of each timing belt 11 is caused by that difference. As a result, the workpiece holding device 6 can always be maintained in a horizontal posture, and a chucking error caused by the workpiece holding device 6 tilting can be reliably prevented. .
[0017]
In the above-described embodiment, the workpiece holding device 6 is suspended and supported by the four timing belts 11. However, the number of the timing belts 11 may be appropriately increased or decreased if necessary. Further, as the timing belt 11 and the pulley 12, instead of the toothed belt and the toothed pulley employed in the above-described embodiment, for example, a perforated belt in which holes are formed at equal intervals in the length direction, and the perforated belt The same effect can be obtained by using a pulley with a protrusion (a kind of sprocket) having a protrusion that engages with a hole in the belt. In short, it is sufficient that the timing belt 11 can be pulled up and pulled down without slipping with respect to the pulley 12, and so long as the pinch rollers 13 and 14 and the guide roller 15 used above are not necessary. You can do it.
[0018]
The configuration for rotating the take-up roller 20 by following the pulley 12 is not limited to the rotational drive of the take-up roller 20 by the motor 16 via the clutch 21 as in the above-described embodiment. The configuration of can be considered. For example, the winding roller 20 is always urged by a spring such as a spring so that the timing belt 11 pulled up by the pulley 12 is automatically wound by the pulled length, and the pulley 12 However, when the timing belt 11 is pulled down, it can be considered that the timing belt 11 is automatically extended against the urging force of the spring. In this case, it is necessary to consider the adjustment of the biasing force of the spring and its life, but the configuration can be simplified compared to the above embodiment. As yet another configuration example, it may be possible to adopt a configuration in which a small actuator for rotationally driving the winding roller 20 is provided and the actuator is controlled in association with the motor 16. In this case, the configuration and control are slightly complicated, but the take-up roller 20 can be operated more reliably and the reliability can be improved.
[0019]
【The invention's effect】
According to a first aspect of the present invention, there is provided a conveying device that lifts the timing belt in a non-slip state by rotating a lifting device for lifting the workpiece holding device while holding the timing belt that supports the workpiece holding device. A pulley comprising a pull-down pulley, a motor that rotationally drives the pulley, and a take-up roller that rotates following the pull-up and pull-down operation of the timing belt by the pulley and takes up and feeds the base end of the timing belt Therefore, the timing belt is wound up by the amount pulled up by the pulley, and the timing belt is fed out by the amount pulled down by the pulley. Related to the amount of winding and feeding The pulling torque by the pulley is always constant regardless of the winding torque by the winding roller, and therefore the lifting stroke of the work holding device is influenced by the thickness of the timing belt. As a result, it is possible to avoid a situation in which the work holding device tilts due to changes in the winding amount or feeding amount of each belt due to deviations in the thickness of the belt, and the work holding device tilts. It is possible to reliably prevent chuck mistakes. Further, since the rotational driving force of the pulley driving motor is transmitted to the take-up roller through the power transmission mechanism and the clutch, the take-up roller can be driven by the pulley without requiring a special drive source and control mechanism. it can. Further, since the toothed belt and the toothed pulley are used, it is possible to reliably pull up and down the desired stroke while holding the timing belt with the pulley.
[Brief description of the drawings]
FIG. 1 is a plan view showing an elevating device in a transport apparatus according to an embodiment of the present invention.
FIG. 2 is a side sectional view of the same.
FIG. 3 is a schematic configuration diagram of a conventional transport device.
FIG. 4 is an enlarged view of the main part of the same.
[Explanation of symbols]
1 rail (track)
2 Traveling device 6 Work holding device 10 Lifting device 11 Timing belt 12 Pulley 16 Motor 20 Winding roller 21 Clutch 23 Belt (power transmission mechanism)

Claims (1)

A traveling device that moves along a track, a workpiece holding device that is suspended and supported by a timing belt from the traveling device, and a lifting device that is mounted on the traveling device and moves up and down the workpiece holding device,
The lifting device includes a plurality of timing belts, a plurality of pulleys that pull and pull down the timing belt in a non-slip state by rotating while holding the timing belt, a motor that rotationally drives the plurality of pulleys, A plurality of take-up rollers that rotate following the pulling-up / down operation of the timing belt by the pulley to take up and feed out the base end portion of the timing belt; and the power from the motor to the plurality of pulleys and the plurality of take-up A power transmission mechanism that transmits to the roller, and a plurality of clutches that connect the power transmission mechanism and the plurality of winding rollers ,
The timing belt comprises a toothed belt having teeth formed on a contact surface with the pulley,
The pulley comprises a toothed pulley meshing with the toothed belt;
The rotational driving force of the motor is transmitted to each of the take-up roller via the power transmission mechanism and the clutch, the take-up roller and configured to rotate allowed driven to said pulley,
When the timing belt is pulled up by the pulley, the clutch winds up the timing belt by the winding roller so that only the portion of the timing belt pulled up by the pulley is wound by the winding roller. When the take-up speed exceeds the pulling speed of the timing belt by the pulley, the rotation of the winding roller is limited, and when the timing belt is pulled down by the pulley, the timing belt is pulled down by the pulley. A conveying device characterized in that the take-up roller is idled so that only the amount of the take-up roller is fed out from the take-up roller .

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