JP5811357B2 - Screw-driven transfer device - Google Patents

Description

  The present invention feeds a conveyance carriage to a screw drive area having a carriage propulsion screw that engages a driven roller on the conveyance carriage side, and stops the conveyance carriage at a work station set at a fixed position in the screw drive area. The present invention relates to a screw-driven conveying device.

  A screw-driven transfer device that propels the transfer cart by engaging a driven roller on the transfer cart side with a cart propulsion screw disposed in the screw drive area is known, for example, from Japanese Patent Application Laid-Open No. 2003-151867. In such a screw-driven transfer device, work stations are set at regular intervals in the screw drive area, and the transfer carriage sent to the start end of the screw drive area is stopped for the required time at each work station. It was considered to implement as a one-way type screw-driven conveying device that is sent from the end of the driving area. In this case, in order to reliably and smoothly start the driven roller of the transport carriage entering the screw drive area in the axial direction with respect to the truck propulsion screw, the carriage for sending the transport carriage for a certain distance between the work stations. The number of revolutions of the propulsion screw must be set to an integer number of fractions, and the phase angle at the screw start end when the carriage propulsion screw stops must be configured to be constant.

JP 2010-47399 A

In the screw-driven transfer device used under the above conditions, when the drive motor of the cart propulsion screw (hereinafter abbreviated as “screw”) is controlled by a servo control system using an electronic gear, the following will be described. The problem became clear. Explaining specific numerical values as examples, for example, machine specifications are
Screw lead: Pb = 160mm
Reduction ratio: n = 1/6
Work station pitch: 5920mm
Servo motor resolution (number of pulses per revolution): Pt = 262144
Then, the carriage can be fed by the working station pitch with 37 rotations of the screw. At this time, the setting value of the electronic gear ratio is command unit: 0.001mm, and the feed amount per servo motor rotation is ΔS. ,
Pt / ΔS = Pt / (Pb × 1000 × n) = 262144 / (160 × 1000 × 1/6) = 262144 / 26666.6666…
Then, when the denominator and numerator are divided by 10 so as to be within the setting range (setting limit) of the electronic gear and the fractional part is rounded off, the setting value of the electronic gear ratio is 26214/2667.
Here, the pulse error per 0.001mm of command unit is
True value (262144 / (160 x 1000 x 1/6))-Electronic gear set value (26214/2667) = 0.001378
That is, since 0.001378 pulses, the cumulative pulse error when trying to move the transport carriage 5920 mm is
5920 / 0.001 × 0.001378 = 8157.76
That is 88157.76 pulses. Therefore, the change in the phase angle of the screw when trying to move the transport carriage 5920mm is
8157.76 / 262144 × 1/6 × 360 ≒ 1.87
In other words, it is 1.87 °, and the actual movement amount of the transport cart is 5920 mm.
1.87 / 360 × 160 ≒ 0.83
That is, it moves by 0.83 mm. Even if the error for one cycle of moving the transport cart is 5920 mm, if the above-mentioned one-way screw-driven transport device is operated continuously indefinitely, the transport cart will stop at each work station. Positional errors are accumulated and increased, and in particular, when the work is automated by a robot installed at each work station, a serious problem that interferes with the work occurs. Furthermore, there is a possibility that the start end portion of the screw drive area, that is, the phase angle of the start end of the screw will change greatly, and the driven roller on the conveyance carriage side cannot be smoothly entered into the start end of the screw.

The present invention proposes a screw-driven conveying device that can solve the conventional problems as described above, and the screw-driven conveying device according to the present invention described in claim 1 will be described later. In order to facilitate understanding of the relationship with the embodiment, the reference numerals used in the description of the embodiment are shown in parentheses, and the carriage is engaged with the driven roller (16a) on the transport carriage (1) side. The conveying cart (1) sent to the screw driving area (2) equipped with the propulsion screw (9A) is moved into the screw driving area (2) by servo driving by the electronic gear of the cart propulsion screw (9A). In the one-way type screw-driven transfer device that is stopped at the work stations (A to E) set at a fixed position, the distance between the work stations (A to E) is determined by the bogie propulsion screws (9A ) Feed per rotation To the control device (24) of the servo motor (21) that is set to an integral multiple of the load amount and drives the cart propulsion screw (9A), When the number of command pulses corresponding to the number of rotations of 9A) is set, and when the control device reaches the set number of command pulses counted in conjunction with the rotation of the cart propulsion screw (9A) It is configured to stop the rotation of the cart propulsion screw (9A), and the work station (with respect to a predetermined phase angle of the spiral body (26) when the cart propulsion screw (9A) has finished rotating an integer number of times ( A to E) are provided with sensors (32a, 32b) for detecting an error in the phase angle when the spiral body (26) is stopped when the transport carriage (1) is stopped, and the detection results of the sensors (32a, 32b) next the instruction path at the time of driving of the carriage propulsion screw (9A) based on Setting the number of the scan is increased or decreased corrected, errors in the stop-time phase angle with respect to the predetermined phase angle is in controlled configurations so as to reduce or zero.

  When the present invention is carried out, specifically, as described in claim 2, the sensor (32a, 32b) has a phase angle of the helical body (26) when the cart propulsion screw (9A) is stopped. A sensor that detects whether the error is deviating from a certain range in either the advance direction or the delay direction is used. Based on the detection result of this sensor (32a, 32b), the next cart propulsion screw (9A) The number of command pulses during driving can be increased or decreased by a fixed value. In this case, as described in claim 3, the carriage propulsion screw (9A) includes a cover that rotates integrally with the screw (9A) and does not interfere with the driven roller (16a) on the transport carriage (1) side. A detection plate (31) is attached, the detection plate (31) is provided with detection portions (34a, 34b) at two locations in the circumferential direction, and the sensor (32a, 32b) is connected to the detection plate (31 ) Of the spiral body (26) when the carriage propulsion screw (9A) is stopped from the detection state of the pair of sensors (32a, 32b). It can be configured to determine whether or not the phase angle error is deviated from a certain range in either the advance direction or the delay direction.

  According to the configuration of the present invention described in claim 1, when the cart propulsion screw is servo-driven by the electronic gear, if there is no error in the number of command pulses to be calculated, the spiral body is stopped when the cart propulsion screw is stopped. Although the phase angle is constant, as explained in paragraph 0005, if an error occurs in the number of command pulses to be calculated, an error on the leading or lagging side will occur in the phase angle of the spiral when the cart propulsion screw is stopped. Occurs. When this error occurs, the number of command pulses at the next drive of the cart propulsion screw is increased or decreased so that this error is reduced or zero. Even when the operation of traveling forward repeatedly at a fixed distance unit so as to stop at a station is continued indefinitely, the error does not increase cumulatively, and the carriage is stopped at an accuracy within an allowable range at each work station. Thus, the intended work can be performed safely and securely at each work station.

  Of course, it is conceivable to provide a sensor that can detect the stop position deviation of the transport carriage stopped at the work station, and to control the drive of the next truck propulsion screw according to the detection result of this sensor. Because the stop position of the transport cart itself is directly detected, it is difficult to detect a minute stop position deviation with high accuracy, and the cost is high due to the need for a high-class sensor. However, according to the configuration of the present invention, it is possible to detect the stop position deviation of the transport carriage with a very high accuracy by using a simple photoelectric sensor, and it is possible to carry out at a low cost. It is possible to correct the stop position deviation. In addition, since the phase angle of the helical body at the start end of the screw drive area, i.e., the start end of the cart propulsion screw, is always maintained substantially constant, the driven roller of each transport carriage fed into the screw drive area is always securely and securely. It can be smoothly engaged with the cart propulsion screw.

  In addition, as the sensor, a sensor that can accurately measure the phase angle error of the screw for propulsion of the cart at the time of stoppage in a minute unit, and the number of correction pulses corresponding to the phase angle error measured by the sensor is used. However, according to the configuration of claim 2, a simple sensor that performs on / off operation like a photoelectric sensor can be used. Thus, the present invention can be carried out simply and easily. In this case, if the error cannot be completely eliminated by correcting the number of command pulses once, the same correction is repeatedly performed a plurality of times for each drive of the cart propulsion screw. Furthermore, according to the configuration of claim 3, for example, compared to the case of adopting a method of detecting the positional deviation in the axial direction of the hypotenuse of the helical body at a constant intermediate position in the length direction of the cart propulsion screw, for example, The present invention can be implemented even more easily.

1A and 1B are diagrams for explaining the overall configuration of the transport apparatus, in which FIG. 1A is a plan view and FIG. FIG. 2 is a longitudinal front view of the screw drive area. FIG. 3 is an enlarged view of a main part of FIG. FIG. 4 is a plan view of the screw drive area. FIG. 5 is a partially cut-away plan view showing a detecting means for detecting a phase angle error at the time of stop provided at an end portion of the cart propulsion screw. FIG. 6A is a front view showing the detecting means, and FIG. 6B is a partially longitudinal front view showing the detection plate and a pair of sensors. 7 is a cross-sectional view taken along line AA in FIG.

  In FIG. 1, reference numeral 1 denotes a transport carriage, which transports the transported object W in the upper screw drive area 2. In the screw drive area 2, work stations A to E are set at equal intervals, and a predetermined work is performed on the object to be transported W on the transport carriage 1 stopped at each work station. A transport carriage return path 3 is provided below the screw drive area 2 in parallel with the screw drive area 2, and the transport carriage 1 delivered from the screw drive area 2 is received at the end of the screw drive area 2. And a carriage descent means 4 having a lifting platform 4a for lowering the carriage to the conveyance carriage return path 3 and sending the conveyance carriage 1 to the conveyance carriage return path 3 is provided. A transport carriage raising means 5 is provided which includes a lift 5 a that receives the transport carriage 1 sent out from the path 3 and raises it to the screw drive area 2 and feeds the transport carriage 1 to the screw drive area 2.

  As shown in FIGS. 2 to 4, the transport cart 1 is composed of a pair of left and right carts 6 </ b> A and 6 </ b> B. On the other hand, in the screw drive area 2, a pair of left and right work floors 7a and 7b are installed so as to sandwich the transported object transport path, and transport carriage guide rails 8A and 8B and a cart propulsion are provided on each of the work floors 7a and 7b. Screws 9A and 9B are provided symmetrically. The transport carriage guide rails 8A and 8B are composed of a lower support rail 10 and an upper steadying rail 11. Each cart 6A, 6B includes a transport object support 12 that supports the left and right sides of one transport object W, a support wheel 13 that rolls on the lower support rail 10, and the support rail. Positioning roller 14 that can rotate around the vertical axis, sandwiching 10 from both the left and right sides, positioning roller 15 that can rotate around the vertical axis, and an upper steadying rail 11 from both the left and right sides, and for cart propulsion Three driven rollers 16a to 16c that are engaged with the screws 9A and 9B and arranged in series at appropriate intervals in the traveling direction are provided.

  The pair of left and right cart propulsion screws 9A and 9B have a bilaterally symmetric structure. As shown in FIG. 4, both ends of the screw unit 17 are supported by bearings 18a and 18b on a straight line, and adjacent screws. As shown by phantom lines in FIG. 2, transmission means 20 that interlocks and connects the two cart propulsion screws 9 </ b> A and 9 </ b> B with each other and the transmission means 20 are connected. In addition, a servomotor 21 with a reduction gear that rotationally drives the two-cart propulsion screws 9A and 9B is provided. The servo motor 21 with a speed reducer is provided with a pulse encoder 22 that is linked to the rotation shaft. The output pulse of the pulse encoder 22, the servo control conditions that have been set, and a phase angle error detecting means at a stop time, which will be described later. A controller 24 that servo-controls the servo motor 21 with a speed reducer is connected via the motor controller 23 based on the phase angle error information at stop 30.

  As shown in FIG. 5 to FIG. 7, each screw unit 17 of the cart propulsion screws 9 </ b> A and 9 </ b> B has a cylindrical body on a drive shaft 25 whose both ends are supported by the bearings 18 a and 18 b, and a spiral strip having a constant width. As shown by the phantom lines in FIG. 7, the drive shaft 25 and the spiral body 26 are connected and integrated by a connecting plate 27 at positions at an appropriate interval in the axial center direction. It is a thing. Further, at both ends of the screw unit 17, fan-shaped plates 28 that support the tip side of the spiral body 26 and are oriented perpendicular to the axis are provided. The drive shaft 25 is obtained by concentrically connecting and integrating end shafts 25b supported by bearings 18a and 18b at both ends of a cylindrical shaft main body 25a that supports the helical body 26. The driven rollers 16a to 16c of the individual carts 6A and 6B are rotatably supported on the left and right horizontal support shafts 29, and the driven rollers 16a to 16c are each screw of the cart propulsion screws 9A and 9B. In the spiral groove between the spiral bodies 26 in FIG. 17, the screw is fitted horizontally in the horizontal direction at a level slightly higher than the axial center level of the screw unit 17. In this state, each screw unit 17 of the cart propulsion screws 9A and 9B is rotationally driven, so that the sides of the spiral body 26 push the driven rollers 16a to 16c in the propulsion direction of the transport cart 1 and each cart unit 6A, 6B is moved forward in the transport cart propulsion direction. Even in the situation where one or two driven rollers pass through the space between the screw single bodies 17 due to the presence of the three driven rollers 16a to 16c in series, any one screw single 17 is used. The carts 6A and 6B can be continuously propelled without stopping, but depending on the length of the screw single 7 and the length of the space between each screw single 17, the purpose of the two driven screws can be achieved. Can be achieved.

  Stop phase angle error detecting means 30 is provided at the start end of one of the left and right cart propulsion screws 9A and 9B. The stop phase angle error detecting means 30 is attached to an end shaft 25b protruding from the bearing 18a of the drive shaft 25 of the cart propulsion screw 9A, and a detected plate 31 that rotates integrally with the cart propulsion screw 9A. It consists of a pair of photoelectric sensors 32a and 32b. The detected plate 31 is formed with a notch 33 at one peripheral portion of a disc whose outer diameter does not enter the moving path of the driven rollers 16a to 16c, and is formed in the radial direction at both ends in the circumferential direction of the notch 33. The detected side portions 34a and 34b are the both sides along the line.

  The pair of photoelectric sensors 32a and 32b are transmission type photoelectric sensors provided with light projecting and receiving devices 35a and 35b located on the left and right sides of the detection plate 31. In this embodiment, the photoelectric sensors 32a and 32b are attached. The mounting plates 36a and 36b are mounted on a work board 7 mounted on a work floor 7a and supported on a support member 37 that supports the upper anti-rail 11 so that the mounting position can be adjusted. The pair of photoelectric sensors 32a and 32b are connected to the detected portions 34a and 34b at two locations in the circumferential direction of the detected plate 31, as shown in FIG. 6B, when the cart propulsion screw 9A stops at a predetermined phase angle. Correspondingly, the optical axis between the light projecting and receiving devices 35a and 35b of both photoelectric sensors 32a and 32b is not blocked by the detected plate 31, but when the cart propulsion screw 9A stops at a phase angle exceeding the allowable range, Either one of the photoelectric sensors 32 a and 32 b is arranged so that the optical axis between the light projecting and receiving devices 35 a and 35 b is blocked by the detected plate 31.

  In the configuration shown in FIG. 5, when the cart propulsion screw 9A rotates in the clockwise direction, the driven rollers 16a to 16c of the cart unit 6A receive thrust in the cart propulsion direction, so that the cart propulsion screw 9A has a predetermined phase angle. 6B, the optical axis of the light emitter / receiver 35a of the photoelectric sensor 32a in FIG. 6B is cut off by the detection plate 31, and conversely, the carriage propulsion screw When 9A stops at a phase angle shifted in a delay direction with respect to a predetermined phase angle, the optical axis of the light emitter / receiver 35b of the photoelectric sensor 32b in FIG. 6B is cut off by the detected plate 31 and turned off. Thus, according to the stop phase angle error detecting means 30 of the present embodiment, it is only possible to determine whether or not the error of the phase angle when the cart propulsion screw 9A stops after an integer rotation is within an allowable range. It is possible to discriminate whether the shift is in the advance direction or the delay direction with respect to the predetermined phase angle.

  In the transfer apparatus shown in FIG. 1, the work stations A to E are set at regular intervals from the entrance of the screw drive area 2 (the start ends of the cart propulsion screws 9A and 9B). This work station setting interval is an integral multiple of the lead (feed distance per rotation) of the screw 17 in the cart propulsion screws 9A and 9B. Therefore, as explained in paragraph 0005, when the lead of the screw 17 is 160 mm and the work station pitch is 5920 mm, the rotation of the pair of left and right cart propulsion screws 9A and 9B that are reversely rotated with each other is 37 rotations. The transport cart 1 waiting at the entrance of the screw drive area 2 and the transport carts 1 stopped at the work stations A to E are sequentially sent to the next work stations A to E, and the transport cart 1 of the final work station E is sent. Is sent to the next transport carriage lowering means 4. Then, the phase angle of the bogie propulsion screw 9A at the time of stop after the bogie propulsion screws 9A and 9B have rotated exactly the unit number of rotations (37 rotations), that is, the detected plate 31 of the phase angle error detecting means 30 at the time of stop. Since the stop phase angle in the circumferential direction of the detected portions 34a and 34b is constant, the photoelectric sensors 32a and 32b are both in the on state (the optical axes of the light projecting and receiving devices 35a and 35b are both blocked by the detected plate 31). Is not configured).

  The carriage 1 sent out from the final work station E by the carriage propelling screws 9A and 9B is fed onto the elevator 4a waiting at the ascending limit position of the carriage carriage lowering means 4, and the retracting included in the elevator 4a. The feeding friction drive wheel 4b is pulled to a predetermined position on the lifting platform 4a, and then the lifting platform 4a is lowered to the lower limit position and connected to the starting end position of the transport carriage return path 3. For example, when the lifting platform 4a is in the ascending limit position or when the lifting platform 4a is in the descending limit position, the object W to be transported on the transport cart 1 is the screw drive area 2 or the transport cart return path from the top of the transport cart 1. What is necessary is just to send to the opposite side to the side with 3. The empty transport carriage 1 on the lifting platform 4a in the lower limit position can be sent out from the lifting platform 4a to the transport cart return path 3 by the reverse rotation of the pull-in / feed friction drive wheel 4b. Although not shown in the figure, a pair of left and right transport carriage guide rails 39A and 39B that are the same as the pair of left and right transport carriage guide rails 8A and 8B provided in the screw drive area 2 are also shown in the transport carriage return path 3. Friction drive means that can drive the carriage 1 at high speed and can be stored is provided. The empty carriage 1 fed to the carriage return path 3 can be driven at high speed by the friction drive means. The vehicle is driven to the end side of the transport carriage return path 3 and is sequentially stored from the end of the transport carriage return path 3 to the upper side.

  When the lifting platform 5a of the transport cart raising means 5 is lowered to the lower limit position and is connected to the end of the transport cart return path 3, the leading empty transport cart 1 is moved by the friction drive means at the end of the transport cart return path 3. While being sent out on the lifting platform 5a, it is drawn to a predetermined position on the lifting platform 5a by the pull-in / feed friction drive wheel 5b provided on the lifting platform 5a, and then the lifting platform 5a is raised to the upper limit position. And connected to the start position of the screw drive area 2. For example, when the lifting platform 5a is in the ascending limit position or the lifting platform 5a is in the descending limit position, the object to be transported W to be operated in the work stations A to E is returned to the screw drive area 2 or the transport carriage. What is necessary is just to transfer on the conveyance trolley 1 on the raising / lowering stand 5a from the opposite side to the path | route 3 side.

  When the lifting platform 5a of the transport cart raising means 5 is in the ascending limit position and is connected to the starting position of the screw driving area 2, the lifting platform 5a is stopped when the cart propulsion screws 9A and 9B in the screw driving area 2 are stopped. By means of the upper pull-out friction drive wheel 5b, the transport carriage 1 on which the article to be transported W is mounted is sent out to the screw drive area 2 side. At this time, the cart propulsion screws 9A and 9B, which have a symmetrical structure and rotate in opposite directions, have the fan-shaped plate 28 at the start end of the screw unit 17 at the start end position of the screw drive area 2 as shown in FIGS. As shown in FIG. 6A, since the driving shaft 25 is stopped at a phase angle located on the side opposite to the side on which the conveyance carriage travel path is located, the carriage alone of the conveyance carriage 1 fed to the screw drive area 2 side. The leading driven rollers 16a provided on 6A and 6B are not in contact with the fan-shaped plate 28 stopped at the starting end positions of the cart propulsion screws 9A and 9B, and are on the conveying cart travel path with respect to the drive shaft 25. It passes through one side and can abut the first hypotenuse of the spiral 26. In this state, the leading driven roller 16a is in contact with the first hypotenuse of the spiral body 26 by continuously applying thrust in the feeding direction to the transport carriage 1 by the pull-in / feed friction drive wheel 5b on the lifting platform 5a. If maintained, the carriage propulsion screws 9A and 9B are driven at the start of the next feeding action, so that the leading driven roller 16a on the transport carriage 1 side is rotated by the helical body 26 in each of the carriage propulsion screws 9A and 9B. It is reliably pulled into the spiral groove between them, and the steering is started by receiving thrust from the two-cart propulsion screws 9A and 9B.

  Thus, in the control device 24 shown in FIG. 2, the electronic gear ratio is set based on the mechanical specification and the electronic gear ratio setting parameter as described in paragraph 0005, and the stop phase angle error detecting means 30 is a correction value for correcting the phase angle error when stopping the cart propulsion screw 9A detected as described above, that is, the cart propulsion screws 9A and 9B for sending the transport cart 1 by the set interval of the work station. A unit pulse number for increasing / decreasing the command pulse number corresponding to the number of rotations is set. In this state, the servo motor 21 with a speed reducer is servo-controlled by the control device 24 via the motor controller 23, and the cart propulsion screws 9A and 9B are rotationally driven by a predetermined number of revolutions, so that the transport cart 1 is set at a work station set interval. However, if an error exceeding the allowable range occurs in the phase angle when the cart propulsion screws 9A and 9B are stopped due to the error in the command pulse number as described in paragraph 0005, the phase angle error at the time of stoppage Information on the phase angle error is sent to the control device 24 via the pair of photoelectric sensors 32a and 32b of the detection means 30, and the next bogie propulsion screw 9A, the number of unit pulses set in advance in the control device 24. The number of command pulses during 9B drive is increased or decreased.

  That is, if the detected phase angle error is an error in the advancing direction, the command pulse number at the next drive time of the cart propulsion screws 9A and 9B is subtracted by the unit pulse number, and the detected phase angle error is reversed. If the error is in the delay direction, the command pulse number at the next drive time of the cart propulsion screws 9A and 9B is added by the unit pulse number. By this processing, the rotational speed of the cart propulsion screws 9A and 9B at the time of the next drive is slightly adjusted in a direction to reduce the phase angle error at the stop, and as a result, the cart propulsion screws 9A and 9B are stopped. The phase angle error at the time falls within an allowable range (a range not detected by the stop phase angle error detection means 30) or becomes zero. If the phase angle error does not fall within the allowable range by one correction process, the stop phase angle error detecting means 30 will detect the presence of the phase angle error again at the time of the stop, so the next drive Sometimes the correction process is executed again, and finally the phase angle error when the cart propulsion screws 9A and 9B are stopped becomes zero or falls within an allowable range.

  With the above-described phase angle correction control at the time of stopping, the conveyance cart travel driving distance corresponding to the number of command pulses calculated is actually set, depending on the machine specifications of the device and the restrictions on the setting of the electronic gear ratio setting parameters. Even if there is a slight error between the distances between the work stations, the errors are accumulated and the position when the carriage is actually stopped at the work station causes an unacceptable shift. Can be prevented. In addition, when the error is accumulated and the driven roller 16a enters the spiral groove between the spiral bodies 26 at the start position of the stopped cart propulsion screws 9A and 9B, The fan-shaped plate 28 that supports the tip enters the entry position of the driven roller 16a, and the driven roller 16a collides with the tip of the spiral body 26 or the fan-shaped plate 28 that supports the tip, and cannot be introduced into the spiral groove. It is also possible to avoid the occurrence of such fatal problems.

  Note that the screw-driven transfer device shown in the embodiment is an example, and the present invention can be applied to a transfer device having a structure in which the transfer carriage is driven and driven by, for example, one carriage propulsion screw. I can do it.

  The screw-driven transfer device of the present invention feeds a transfer carriage from one end to the screw drive area, temporarily stops each transfer carriage at work stations set at regular intervals in the screw drive area, and finally the transfer carriage As a one-way type screw-driven transfer device that feeds out from the other end of the screw drive area, it can be used in automobile assembly lines and the like.

DESCRIPTION OF SYMBOLS 1 Transfer trolley 2 Screw drive area 3 Transfer trolley return route 4 Transfer trolley descent means 5 Transfer trolley lift means 6A, 6B Dolly alone 8A, 8B Carriage trolley guide rails 9A, 9B Dolly propelling screws 16a-16c Driven roller 17 Screw alone DESCRIPTION OF SYMBOLS 20 Transmission means 21 Servo motor with reduction gear 22 Pulse encoder 23 Motor controller 24 Control apparatus 25 Drive shaft 26 Spiral body 28 Fan plate 30 Stop phase angle error detection means 31 Detected plates 32a and 32b Photoelectric sensor 33 Cuts 34a and 34b Detected 35a, 35b Projector / receiver

Claims (3)

The carriage that has been fed to the screw drive area provided with the carriage propulsion screw that engages with the driven roller on the carriage is moved to a fixed position in the screw drive area by servo drive by the electronic gear of the carriage propulsion screw. in the transport device of the screw drive in one-way type so as to stop at a set working station, interval between each work station is set to an integral multiple of one rotation per feeding amount of carriage propulsion screw, the carriage The control device of the servo motor that drives the propulsion screw is set with the number of command pulses corresponding to the number of rotations of the cart propulsion screw for feeding the transport cart for the set interval of the work station. When the count value of the command pulse transmitted in conjunction with the rotation of the screw reaches the set number Is configured to stop the rotation of the bogie propulsion screw, with respect to the predetermined phase angle of the spiral when the bogie propulsion screw has finished rotating an integer number of times, sensor for detecting an error in the stop-time phase angle helix is provided, the set number of the command pulses at the time of driving the next truck propulsion screw on the basis of the detection result of the sensor is increased or decreased corrected, the predetermined phase angle A screw-driven conveying device configured to be controlled such that an error in the phase angle at the time of stopping with respect to the power is reduced or zero.   The sensor is a sensor for detecting whether the phase angle error of the helical body at the time of stopping the cart propulsion screw is deviated from a certain range to either the advance direction or the delay direction, and the detection result of this sensor The screw-driven transfer device according to claim 1, wherein the number of command pulses at the time of driving the cart propulsion screw is increased / decreased by a predetermined value based on the above. A detection plate that rotates integrally with the screw and does not interfere with the driven roller on the conveyance carriage side is attached to the carriage propulsion screw. The detection plate is provided with detection portions at two locations in the circumferential direction. A pair of the sensors are provided corresponding to the two detection portions of the detection plate, and the phase angle error of the spiral when the cart propulsion screw is stopped is constant from the detection state of the pair of sensors. The screw-driven transfer device according to claim 2, wherein the screw-driven transfer device is configured to determine whether the direction is shifted from the range to either the advance direction or the delay direction.

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