JP3709779B2 - Linear conveyor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a linear conveyance device.
[0002]
[Prior art]
In a linear transport device using a linear motor as a drive source, when performing maintenance on a transport cart that is connected and integrated with the mover, if the transport line is straight, the transport cart must be removed by removing the stopper from the end. . When the transfer line is endless, maintenance of the mover and the transport carriage cannot be performed unless the mover and the transport carriage are disassembled. In addition, when the removed mover is reinserted, accurate control cannot be performed unless adjustment is made so that the position of the mover and the position management information managed by the controller do not contradict each other. For this reason, the maintenance takes time and is not efficient.
[0003]
[Problems to be solved by the invention]
However, if the transport cart and mover can be easily removed in the middle of the transport line, and the position management information managed by the controller can be initialized when the removed transport cart and mover are remounted, maintenance is also possible. It becomes easy and does not interfere with the position control of the mover after returning. The present invention has been made in view of the above points, and an object of the present invention is to provide a linear transport device that facilitates maintenance of a transport cart or the like that is connected and integrated with a mover.
[0004]
[Means for Solving the Problems]
In order to achieve the above object, a linear transport apparatus according to claim 1, wherein a mover made of a plurality of permanent magnets, and a stator made by connecting a plurality of coil units along a traveling track of the mover, the disposed in each coil unit consists of a sensor for detecting the relative position of the mover permanent magnets and the stator coil, energizing the switching means for switching the energization of the stator coil by the detection signal from the sensor Similarly, a movable magnet linear motor controlled by a control unit having a current position calculating means for calculating a current position of the mover by counting a detection signal of the sensor is installed in a transfer line, and the mover In the linear transport device in which the transport carriage is connected and integrated, only the mechanical part excluding the electrical wiring in the middle of the traveling track including the stator is disposed on the transport base. And configured to be separated from the conveyor line together with the movable element, the Rukoto to separate the intermediate portion of the running track from the transfer line, together with the control unit shifts to a standby state in which the energized state is maintained, the transport carriage In addition, the current position calculation means counts in the process of making the traveling track separated from the transportation line detachable and inserting the transportation carriage and movable body into the traveling track separated from the transportation line. The controller unit is returned to a controllable state by resetting the value and returning the separated intermediate portion of the traveling track to the transport line .
[0005]
Further, the linear transport device according to claim 2 is a travel track that is connected to each of the sensors via a selection switch and separated from the transport line based on a detection signal of the sensor in the configuration according to claim 1. Absolute position detection means for detecting the absolute position set in the part, and in the process of inserting the carriage and the mover into the traveling track part, the current position calculation based on the absolute position detection signal of the absolute position detection means Control means for resetting the count value of the means is provided.
[0006]
[Operation and effect of the invention]
The linear transport device according to claim 1 of the above configuration is configured to be separable from the transport line together with the transport carriage and the mover, only the mechanical part excluding the electrical wiring in the middle of the traveling track including the stator, When the intermediate part of the traveling track is separated from the transport line, the transport carriage and the mover can be detached from the traveling track separated from the transport line. The control unit that controls the linear motor shifts to the standby state. In addition, the count value of the current position calculation means is reset in the process of inserting the transport carriage and the mover into the traveling track portion separated from the transport line, and when the intermediate portion of the separated traveling track is returned to the transport line, the standby state The controller unit returns to the controllable state. Therefore, it is possible to carry out maintenance by taking out the mover and the transport carriage without disassembling. In addition, the count value of the current position calculation means is reset in the process of inserting the transport carriage and the mover into the traveling track portion separated from the transport line, and the position management information managed by the controller unit can be automatically initialized. There is no need to make adjustments so that the position of the mover and the position management information managed by the controller unit do not contradict each other , and the controller unit immediately returns to the controllable state when the intermediate part of the traveling track is returned to the transport line. from, it can be re-run in a short period of time after maintenance.
[0007]
Moreover, the linear conveyance apparatus of Claim 2 can detect the absolute position set to the traveling track part separated from the conveyance line by the absolute position detection means based on the detection signal of the sensor. The control means resets the count value of the current position calculation means when the absolute position detection signal is output in the process of inserting the carriage and the mover into the traveling track portion. Therefore, since it is not necessary to attach an external sensor or limit switch as a reset means, it is possible to contribute to cost reduction and to improve the reliability of the linear transport device.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
A first embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a schematic configuration diagram of a magnet movable linear motor 1 serving as a drive source. The mover 2 is configured such that a plurality of mover permanent magnets 3 having the same shape are arranged and fixed on a yoke (not shown) so that the mover 2 can travel along a traveling track 31. Each mover permanent magnet 3 is magnetized in the thickness direction, and adjacent ones have different polarities. The stator 4 is configured by arranging a plurality of coil units 11 along a traveling track 31.
[0009]
The coil unit 11 includes a coil body 12, a pair of sensor units 13, and a switch circuit 14. The coil body 12 integrates six stator coils 12a, 12b, 12c and 12a ', 12b', 12c 'having the same shape by resin sealing or the like, and stator coils 12a, 12a', 12b, 12b. 'And 12c, 12c' are connected in series and three-phase star connection is made.
[0010]
The sensor unit 13 detects a relative position between the mover permanent magnet 3 and the stator coils 12a to 12c ′, and is formed as a set of three magnetosensitive elements 13a, 13b, and 13c. 12 at both ends. As each of the magnetic sensitive elements 13a, 13b, and 13c, for example, a Hall element is used. The interval between the magnetic sensing elements 13a, 13b, and 13c is set to 1/3 of the magnetic pole pitch of the mover permanent magnet 3, so that a signal is output at a pitch of 1/3 of the magnetic pole pitch. Each of the magnetic sensitive elements 13a, 13b, and 13c is connected to the OR circuit 15 and the sensor bus line 16.
[0011]
The switch circuit 14 is turned on by a signal output from the sensor unit 13 to switch the coil body 12 to a state where energization is possible. For this reason, the switch circuit 14 is connected to each sensor unit 13 via the OR circuit 15. And since the connection mode of the coil body 12 is a three-phase star connection, the switch circuit 14 is comprised by the two switches 14a and 14b interposed in the three-phase circuit which connects the stator coils 12a and 12b. The switches 14a and 14b and the stator coil 12c are connected to the power bus line 17, respectively.
[0012]
The control unit 21 includes an operation direction instruction circuit 22, a control circuit 23 connected to the sensor bus line 16, and a transistor circuit 24 connected to the power bus line 17. The operation direction instruction circuit 22 instructs the operation direction of the mover 2 to the control circuit 23. The control circuit 23 includes a mover position detection circuit 23a, a mover speed detection circuit 23b, a mover speed control circuit 23c, and the like.
[0013]
The mover position detection circuit 23a counts signals output from the magnetic sensing elements 13a, 13b, and 13c of the sensor unit 13 to calculate the current position of the mover. Similarly, the mover speed detection circuit 23 b detects the speed of the mover 2 from the time interval of the signal output from the sensor unit 13. Further, the mover speed control circuit 23c converts a deviation between the detected speed of the mover 2 and a preset target speed into a PWM output value.
[0014]
The control circuit 23 determines the excitation phase of the stator coils 12a to 12c ′ based on the operation direction instruction signal and the relative position signal, and outputs a speed control signal based on the PWM output value to the transistor circuit 24. The transistor circuit 24 turns on and off the six transistors Tra, Tra ′, Trb, Trb ′ and Trc, Trc ′ by the speed control signal to excite the stator coils 12a to 12c ′, and Control the speed. Thereby, thrust based on the Fleming's left-hand rule is generated in the excited stator coils 12a to 12c ′ and the mover permanent magnet 3, and the mover 2 moves in the direction instructed by the operation direction instruction signal.
[0015]
FIG. 2 is an explanatory view showing a linear transport device 30 using the magnet movable linear motor 1 having the above-described configuration as a drive source. The conveyance line L is linear, and the conveyance carriage 33 reciprocates between work stations 32a and 32b provided at both ends. A travel track 31 of the mover 2 connected and integrated with the transport carriage 33 is laid along the transport line L, and the coil unit 11 is disposed over the entire length. The traveling track 31 is configured such that the intermediate portion 31 a is divided and can be separated from the transport line L together with the coil unit 11. In addition, the electric wiring 19 of the coil unit 11 of this intermediate part 31a is connected in series with the electric wiring 19 of the other coil unit 11 fixed to the conveyance line L via the flexible electric wire 19a without being separated. Yes.
[0016]
The intermediate portion 31 a of the traveling track 31 that can be separated from the transport line L is set to be not less than the length of the transport carriage 33 and an integral multiple of the coil unit 11, for example, twice as long. The distance G between the ends of the intermediate portion 31 a of the traveling track 31 and the portion fixed to the transport line L is matched with the synchronous pitch of the magnet movable linear motor 1. Corresponding to the intermediate portion 31 a of the traveling track 31, a slide rail 34 orthogonal to the transport line L is laid. With this slide rail 34, the intermediate portion 31 a of the traveling track 31 can be slid forward while the transport carriage 33 is placed and separated from the transport line L. In a state where the intermediate portion 31 a of the traveling track 31 is separated from the transport line L, the transport carriage 33 and the mover 2 can be attached to and detached from the intermediate portion 31 a of the traveling track 31.
[0017]
Further, in the process of mounting the transport carriage 33 and the mover 2 on the intermediate portion 31a of the traveling track 31 separated from the transport line L, the count value of the mover position detection circuit 23a is reset. That is, a reset switch 35 is disposed in the intermediate portion 31 a of the traveling track 31 and is connected to the control unit 21 by the reset signal line 18. The reset switch 35 detects the mover 2 and outputs a reset signal to the control unit 21.
[0018]
By this reset signal, the count value of the mover position detection circuit 23a is reset, and the origin for calculating the current position is automatically set. The reset switch 35 detects the mover 2 and may be a mechanical limit switch or a non-contact switch. The slide rail 34 is provided with a limit switch (not shown) that detects that the intermediate portion 31a of the traveling track 31 has been pulled out and puts the control unit 21 in a standby state.
[0019]
When performing maintenance on the transport carriage 33 and the mover 2 in the linear transport apparatus 30 described above, first, the intermediate portion 31a of the traveling track 31 on which the transport carriage 33 is placed is slid out by the slide rail 34, and then transported. Separate from line L. The electrical connection between the coil unit 11 and the control unit 21 arranged in the intermediate portion 31a of the traveling track 31 separated from the transport line L is held by the flexible wire 19a. The separation of the intermediate portion 31a of the traveling track 31 from the transport line L is detected by a limit switch (not shown) disposed on the slide rail 34, and the control unit 21 enters a standby state where the energized state is maintained .
[0020]
After the maintenance is completed, when the transport carriage 33 and the mover 2 are attached to the intermediate portion 31a of the traveling track 31 separated from the transport line L, the reset switch 35 detects the passage of the mover 2 and the reset signal is on standby. It is output to the control unit 21 inside. By this reset signal, the count value of the mover position detection circuit 23a is reset, and the origin for calculating the current position is automatically set. Then, by returning the intermediate portion 31a of the traveling track 31 to the transport line L, the control unit 21 immediately returns from the standby state to the controllable state.
[0021]
Since the linear transport device 30 described above is configured so that the intermediate portion 31a of the traveling track 31 can be separated from the transport line L together with the transport carriage 33 and the mover 2, the mover 2, the transport carriage 33 and the like can be removed without disassembling. Maintenance can be performed with the minimum required work time. In addition, the count value of the mover position detection circuit 23a is reset in the process of attaching the transport carriage 33 and the mover 2 to the intermediate portion 31a of the travel track 31 separated from the travel track L, and the current position is calculated. Since the origin is automatically set and the intermediate portion 31a of the traveling track 31 is returned to the transport line L, the control unit 21 immediately returns to the controllable state from the standby state. It is not necessary to adjust the count values of the 21 mover position detection circuits 23a so as not to contradict each other, and the operation can be restarted in a short time after maintenance. In this case, by exchanging the transport carriage 33 and the mover 2 that have been removed from the spare ones, it is possible to restart the transport apparatus 30 with a minimum stop time.
[0022]
Further, when the transport device 30 includes a plurality of sets of transport carts 33 and movers 2, operation with the remaining transport carts 33 and movers 2 is possible even if a set of transport carts 33 and movers 2 is removed. Further, it is possible to restart the operation with minimum downtime for stopping the transfer device 30.
[0023]
(Second Embodiment)
FIG. 3 is a schematic configuration diagram of a magnet movable linear motor 51 serving as a drive source of the linear conveyance device 31 of the second embodiment. Since the basic configuration is common to the magnet movable linear motor 1 of the first embodiment, the same components are denoted by the same reference numerals, and detailed description thereof is omitted. As shown in FIG. 3, the output of the OR circuit 15 applied to the switch circuit 14 is connected to two absolute position signal lines 52 a and 52 b via a selection switch 54. When the selection switch 54 is connected to the one contact 54a side, the output of the OR circuit 15 which is the output of the sensor unit 13 is applied to the absolute position signal line 52a and is connected to the other contact 54b. In this case, the output of the OR circuit 15 is applied to the absolute position signal line 52b. The absolute position signal lines 52 a and 52 b are connected to the control circuit 23 of the control unit 21.
[0024]
FIG. 4 schematically shows the relationship between the control circuit 23 shown in FIG. 3 and the sensor unit 13 of each coil unit 11, and from each of the magnetic sensing elements 13 a, 13 b, 13 c to the OR circuit 15 and the sensor bus line 16. The signal waveforms to be output and the signal waveforms of the absolute position signal lines 52a and 52b are shown. Here, for convenience of illustration, only six coil units 11-1 to 11-6 are shown as coil units. The selection switches 54 of the coil units 11-1 and 11-2 are connected to one contact 54a side. The selection switches 54 of the coil units 11-3 and 11-4 are not connected to any contact. The selection switches 54 of the coil units 11-5 and 11-6 are connected to the other contact 54b side.
[0025]
When the mover 2 corresponds to the coil units 11-1 and 11-2, a high-level detection signal is output to the one absolute position signal line 52a via the OR circuit 15, and the other absolute position signal line. 52b is kept at the low level. When the mover 2 corresponds to the coil units 11-3 and 11-4, both the absolute position signal lines 52a and 52b are kept at the low level. When the mover 2 corresponds to the coil units 11-5 and 11-6, one absolute position signal line 52a is kept at a low level, and a high level detection signal is sent to the other absolute position signal line 52b. Is output via the OR circuit 15.
[0026]
And as shown in FIG. 5, while the part corresponding to the said coil units 11-2 and 11-3 is made into the intermediate part 31a of the traveling track 31 separable from the conveyance line L, this coil unit 11-2, The origin Op for the current position calculation is set at the boundary 11-3. Accordingly, when the transport carriage 33 and the mover 2 that have been maintained from the right side of the intermediate portion 31a separated from the transport line L are mounted, when the mover 2 passes the boundary between the coil units 11-3 and 11-2, The absolute position signal line 52b remains at the low level, but the absolute position signal line 52a is switched from the low level to the high level. When the switching of the signal level of the absolute position signal line 52a is input, the control unit 21 resets the count value of the mover position detection circuit 23a.
[0027]
Therefore, the count value of the mover position detection circuit 23a can be automatically reset in the process of mounting the transport carriage 33 and the mover 2 that have been maintained on the intermediate portion 31a of the travel track 31 separated from the travel track L. This eliminates the need for an external sensor or limit switch as a reset means for automatically setting the origin when calculating the current position, thus contributing to cost reduction and increasing the reliability of the linear transport device. be able to.
[0028]
Note that the origin Op when calculating the current position can be set to the switching position of the signal level of the absolute position signal line 52a or 52b, and the portions of the coil units 11-4 and 11-5 are moved from the transport line L. An intermediate portion 31a of the separable traveling track 31 can also be used.
[0029]
The separation of the intermediate portion 31a of the traveling track 31 from the conveyance line L in the conveyance device 30 of the first and second embodiments may be performed manually or automatically. Further, the separation direction may be any of left and right and up and down directions. The transport line may be an endless one in which the transport cart circulates through the work station. Then, by connecting another linear motor conveyance device or a different type of conveyance device to the intermediate portion 31a separated from the conveyance line L, a conveyance device with further expanded applications and functions can be configured.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a magnet movable linear motor that is a drive source of a linear conveyance device according to a first embodiment.
FIG. 2 is an explanatory view schematically showing the linear transport device according to the first embodiment.
FIG. 3 is a schematic configuration diagram of a magnet movable linear motor that is a drive source of a linear transport device according to a second embodiment.
4 is a connection diagram of the magnet movable linear motor shown in FIG. 3 and signal waveform diagrams of a magnetosensitive element and an absolute position signal line. FIG.
FIG. 5 is an explanatory view schematically showing a linear transport device according to a second embodiment.
[Explanation of symbols]
2. Mover 4 ... Stator 13a-13c ... Magnetosensitive element 21 ... Control unit 23 ... Control circuit 23a ... Mover position detection circuit 23b ... Mover speed detection Circuit 23c ... Mover speed control circuit 30 ... Linear transfer device 31 ... Travel track 31a ... Intermediate portion 33 ... Transfer carriage 35 ... Reset switch 52a, 52b ... Absolute position signal Line 54 ... selection switch 54a, 54b ... contact L ... transport line

Claims (2)

A mover composed of a plurality of permanent magnets, a stator formed by connecting a plurality of coil units along a traveling track of the mover, and the mover permanent magnet and the stator coil disposed in each of the coil units. consists of a sensor for detecting the relative position between the calculated and energization switching means for switching the energization of the stator coil by the detection signal from the sensor, also the current position of the movable element by counting the detection signal of the sensor In a linear transport apparatus in which a movable magnet linear motor controlled by a control unit having a current position calculating means is installed in a transport line, and the movable element and transport carriage are connected and integrated.
Only mechanical portion excluding the electrical wiring in the middle of the running track that includes the stator, together with the transport vehicle and the movable element is detachably composed of the conveying line, Ru to separate the intermediate portion of the running track from the transport line As a result, the control unit shifts to a standby state, and the transport carriage and the mover can be freely attached to and detached from the travel track separated from the transport line, and transported to the travel track portion separated from the transport line. The controller unit is in a controllable state by resetting the count value of the current position calculation means in the process of inserting the carriage and the mover, and returning the separated intermediate part of the traveling track to the transport line Returning to the linear transport device.   Absolute position detecting means connected to each of the sensors via a selection switch and detecting an absolute position set in a traveling track portion separated from the transport line based on a detection signal of the sensor, and transported to the traveling track portion 2. The linear device according to claim 1, further comprising a control unit that resets a count value of the current position calculation unit based on a detection signal of the absolute position detection unit in a process of inserting the carriage and the mover. Conveying device.

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