TW201813898A - Transfer device has a fork moving in a manner that the deceleration speed of the decelerating movement is greater than the acceleration speed of the accelerating movement - Google Patents

Abstract

The present invention is a transfer device 20 including a fork 22 for carrying and supporting a container 90, and the container 90 is transferred by moving the fork 22 between the swivel table 21 and the article storage portion 98 of the article storage rack 97. The fork 22 performs an accelerating movement that accelerates to a prescribed speed, and a decelerating movement that decelerates from the prescribed speed, and moves in a manner that the deceleration speed of the decelerating movement is greater than the acceleration speed of the accelerating movement.

Description

Transfer device

The present invention relates to a transfer device, for example, a stacker crane or an article transfer trolley provided in an automatic warehouse, and a fork portion on which the support article is placed is placed on the transfer device body and the article. Move between transfer positions to transfer items.

The transfer device is provided, for example, in a stacker crane or the like that transfers articles between a plurality of article storage units in an article storage rack of an automatic warehouse, and performs storage of the articles transferred to the article storage rack to the plurality of article storage units. A warehouse-in operation in any one of the two or a warehouse-out operation in which an article stored in any one of the plurality of article storage units is stored (for example, refer to Patent Document 1). The transfer device includes a fork portion on which the article is supported, and the fork portion is extended and moved from the transfer device body to the article transfer position, and from the article transfer position to the transfer device body. Shrink and move to transfer items. The transfer device performs an extension movement or a contraction movement of the fork portion by accelerating the fork portion in a stationary state, and completes an extension movement or a contraction movement of the fork portion by decelerating the fork portion. The extension movement and the contraction movement of the fork section are performed by driving a driving section such as a stepping motor. [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2007-99424

[Problems to be Solved by the Invention] However, in the transfer device as described above, there may be a limitation of the drive unit due to a step loss of the motor, etc., or an increase in the weight of an article placed on the fork portion, etc. However, the acceleration during the acceleration movement of the fork cannot be increased to a certain speed or more. Therefore, there is a problem that the time required for the entire extension movement or contraction movement of the fork portion becomes longer, and the fork portion cannot be moved between the transfer device body and the article transfer position in a short time.

Therefore, an object of the present invention is to provide a shift that can shorten the time required for the entire extension and contraction movement of the fork portion even when the acceleration during the acceleration movement of the fork portion cannot be increased above a certain speed.载 装置。 Load device. [Means for solving problems]

The problems to be solved by the present invention are as described above, and the means for solving the problems are described next.

That is, the transfer device of the present invention is a transfer device that includes a fork portion on which a supporting article is placed, and is moved by moving the fork portion between the transfer device body and the article transfer position. For an article, the fork portion at least accelerates to a predetermined speed, and decelerates to decelerate from the predetermined speed, and moves so that the deceleration of the decelerated movement is greater than the acceleration of the accelerated movement. In the above configuration, the movement time of the deceleration movement of the fork portion is shorter than the movement time of the acceleration movement of the fork portion.

The transfer device of the present invention is the transfer device as described above, wherein the fork portion performs an elongation movement from the transfer device body toward the article transfer position, and a contraction movement from the article transfer position toward the transfer device body, The extension movement and the contraction movement are accompanied by at least an acceleration movement accelerated to a predetermined speed and a deceleration movement decelerated from the predetermined speed. The deceleration of the deceleration movement during the contraction movement is greater than the deceleration movement during the extension movement. Deceleration way to move. In the above configuration, the moving speed during the deceleration movement of the fork portion near the transfer device body is faster than the moving speed during the deceleration movement of the fork portion near the article transfer position.

The transfer device of the present invention is the transfer device as described above, wherein the fork portion performs an elongation movement from the transfer device body toward the article transfer position, and a contraction movement from the article transfer position toward the transfer device body, The extension movement and contraction movement are accompanied by at least an acceleration movement accelerated to a predetermined speed and a deceleration movement decelerated from the predetermined speed, and the acceleration of the acceleration movement during the extension movement is greater than the acceleration of the acceleration movement during the contraction movement. Way to move. In the above configuration, the movement speed during acceleration movement of the fork portion near the transfer device body is faster than the movement speed during acceleration movement of the fork portion near the article transfer position.

The transfer device of the present invention is the transfer device as described above, which includes a drive unit that accelerates the fork portion from a stationary state to the predetermined speed and decelerates the fork portion from the predetermined speed. The driving portion applies a force greater than a static friction force acting on the fork portion during the acceleration movement of the fork portion to the fork portion during the acceleration movement and the deceleration movement of the fork portion. In the above configuration, the driving portion applies a force greater than the dynamic frictional force acting on the fork portion when the fork portion is decelerated.

The transfer device of the present invention is the transfer device as described above, wherein the driving portion applies a force equal to the force applied to the fork portion during the accelerated movement during the decelerating movement. . In the above configuration, the driving portion applies a force greater than the dynamic frictional force acting on the fork portion when the fork portion is decelerated. [Effect of the invention]

According to the transfer device of the present invention, even if the acceleration of the fork portion cannot be increased to a certain speed or higher due to the limitation of a drive portion such as a motor that drives the fork portion (for example, out of step of the motor), etc. In this case, the time required for the entire movement of the fork portion can also be shortened.

The transfer device 20 of the present invention will be described. As shown in FIGS. 1 and 2, the transfer device 20 is provided in a stacker crane 10. The stacker crane 10 moves a container 90 (an example of an "item") containing a plate-like body such as an unfinished product of a semiconductor product or a liquid crystal display device into an automatic warehouse 95 for storing the container 90, or Automatic warehouse 95 moves out. The stacker crane 10 transfers the container 90 to an article storage rack 97 in the automatic warehouse 95, and the article storage rack 97 is configured by a traveling rail 96 that is a track of the stacker crane 10, or The containers 90 stored in the article storage rack 97 are taken out from the article storage rack 97 and carried out from the automatic warehouse 95. The stacker crane 10 mainly includes: a traveling trolley 11 that can move freely along the traveling rail 96, a pair of lifting rods 12 that are erected on the traveling trolley 11 and tow and support the lifting platform 13 freely, and a supporting device 20 that supports the transfer device 20 Lifting platform 13. The stacker crane 10 is provided with a pair of lifting rods 12 on the same straight line as the moving direction of the stacker crane 10 at both end portions of the traveling carriage 11. A mast 12 connects the upper ends of each other by an upper frame 14, and lifts and supports the lifting platform 13 in a freely movable manner. The traveling cart 11 includes a traveling electric motor 11 a (see FIG. 4), and moves by the driving of the traveling electric motor 11 a to transport the lifting platform 13 to a target position. The elevating table 13 includes an elevating electric motor 12 a (see FIG. 4), and the elevating is driven by the elevating electric motor 12 a to carry the fork 22 to the article storage unit 98 of the target article storage rack 97.

The lifting platform 13 mounts a transfer device 20 supporting the present invention. The transfer device 20 is a fork-type transfer device that includes a turntable 21 (an example of a “transfer device body”) that is rotatably mounted on the lift table 13, and a support container 90 that is mounted on the turntable 21. A fork 22 that moves forward and backward (an example of a “fork portion”) and an electric motor 25 for an advance and retreat that moves the fork 22 forward and backward (an example of a “drive portion”, see FIG. 4). The transfer device 20 is an article storage unit that moves the fork 22 forward and backward by using a direction orthogonal to the traveling direction of the stacker crane 10 as the transfer direction of the container 90 to place the container 90 on the turntable 21 and the article storage rack 97. 98 (an example of "item transfer position"). As shown in FIG. 3A and FIG. 3B, the fork 22 includes: a telescopic link mechanism 23, one end side of which is mounted on the turntable 21; and a mounting body 24, which is supported by the other end side of the link mechanism 23 and connected by The lever mechanism 23 extends and retracts with respect to the turntable 21 while being retracted. The link mechanism 23 includes a pair of operation links 23a, whose base ends are freely connected to the turntable 21 around the upper and lower shaft cores P, and a pair of rocking links 23b, whose base ends are free to rotate around the upper and lower shaft cores P. The front end portion of the operation link 23 a is grounded, and the front end portion is rotatably connected to the base end portion of the mounting body 24 around the upper and lower shaft cores P. The link mechanism 23 is rotated in a state in which the pair of operation links 23 a are synchronized by the forward and backward electric motor 25, whereby the entire link mechanism 23 is expanded and contracted. That is, the transfer device 20 is configured such that the advancement and retraction directions of the placement body 24 can be switched to one side or the other side of the pair of article storage racks 97 by turning around the upper and lower shaft cores P of the turntable 21. In addition, the mounting body 24 can be moved to the turntable 21 by the contraction movement of the link mechanism 23 (see FIG. 3A), and the mounting body 24 can be moved to the article by the extension movement of the link mechanism 23. The mode of the state (see FIG. 3B) of the article storage unit 98 of the storage rack 97 is switched. The mounting body 24 is a member on which the support container 90 is mounted, and is configured so that the bottom surface of the container 90 can be mounted.

When transferring the container 90 to and from the article storage section 98 of the article storage rack 97, the transfer device 20 performs extension and contraction movement of the fork 22 (link mechanism 23). Specifically, when the container 90 is carried into the article storage unit 98 by the transfer device 20, the fork 22 on which the container 90 is placed is extended from the turntable 21 to the article storage unit 98, and the container 90 is stored in the article. After the portion 98 is removed, the fork 22 is retracted from the article storage portion 98 and moved to the turntable 21. On the other hand, when the container 90 is carried out from the article storage unit 98 by the transfer device 20, the fork 22 is extended from the turntable 21 to the article storage unit 98, and the container 90 is picked up by the fork 22, and then the container 90 is loaded. The fork 22 holding the supporting container 90 is contracted and moved from the article storage unit 98 to the turntable 21. In addition, when the transfer device 20 performs extension and contraction movements of the fork 22, at least the acceleration movement that accelerates the stationary fork 22 to a predetermined speed and the deceleration movement that decelerates the fork 22 from the predetermined speed . Specifically, as shown in FIG. 5, the transfer device 20 accelerates the stationary fork 22 to a predetermined speed during the elongation and contraction movements of the fork 22, and causes the load to be maintained while the predetermined speed is maintained. The fork 22 moves, and then the fork 22 is decelerated from a predetermined speed at a predetermined deceleration start time. That is, the transfer device 20 performs the extension movement and the contraction movement of the fork 22 in the order of acceleration movement, constant speed movement, and deceleration movement. More specifically, as shown in the chart 1 of FIG. 5, when the transfer device 20 carries the container 90 into the article storage unit 98, the stationary fork 22 on which the support container 90 is placed is accelerated to the prescribed value. The speed is such that the fork 22 is moved while maintaining the predetermined speed, and then decelerated from the predetermined speed at a predetermined deceleration start time. After the container 90 is unloaded from the article storage unit 98 from the fork 22, the stationary fork 22 in which the supporting container 90 is not placed is accelerated to the predetermined speed, and the fork 22 is maintained while maintaining the predetermined speed. Move and then decelerate from the prescribed speed at a prescribed deceleration start time. Similarly, as shown in chart 2 of FIG. 5, when the transfer device 20 carries the container 90 out of the article storage unit 98, the stationary fork 22 without the supporting container 90 is accelerated to the predetermined speed. The fork 22 is moved while maintaining the predetermined speed, and then decelerated from the predetermined speed at a predetermined deceleration start time. After the container 90 of the article storage unit 98 is picked up by the fork 22, the stationary fork 22 on which the supporting container 90 is placed is accelerated to the predetermined speed, and the fork 22 is moved while the predetermined speed is maintained. It then decelerates from the prescribed speed at a prescribed deceleration start time. The predetermined speed refers to a maximum moving speed of the fork 22 when the fork 22 is moved between the turntable 21 and the article storage portion 98 of the article storage rack 97 during the extension and contraction movement. The predetermined speed is set based on the driving force of the electric motor 25 for advancing and retreating, and the presence or absence of the container 90 placed on and supported by the placing body 24. The forward / backward electric motor 25 includes, for example, a stepping motor or a servo motor, which is a motor that rotates in synchronization with the input pulse.

As shown in FIG. 4, the stacker crane 10 includes a crane control device 17 that controls the operation of the stacker crane 10 based on an instruction from the above-ground controller 80. The above-ground controller 80 instructs the crane control device 17 to carry in the container 90 to any one of the plurality of article storage sections 98 of the article storage rack 97 and the plurality of article storage sections to be stored in the article storage rack 97. A carry-out instruction for carrying out the container 90 in any one of 98. The crane control device 17 connects a rotary encoder 11b for travel and a rotary encoder 12b for lifting, and inputs detection information from the rotary encoder 11b for rotation and the rotary encoder 12b for lifting. The crane control device 17 includes a movement control unit 18 that controls the drive of the electric motor 11a for movement; a lift control unit 19 that controls the drive of the electric motor 12a for elevation; and an advance and retreat control unit 26 that controls the drive of the electric motor 25 for advance and retreat. The travel control unit 18 controls the drive of the travel electric motor 11 a based on the detection information of the travel rotary encoder 11 b to move the travel cart 11 to the target position of the lifting platform 13. The lift control unit 19 controls the drive of the lift electric motor 12a based on the detection information of the lift rotary encoder 12b, and raises and lowers the lift table 13 to a target position where the fork 22 moves forward and backward. The forward / backward control unit 26 controls the drive of the forward / backward electric motor 25 to perform extension and contraction movements of the fork 22.

In the crane control device 17, based on the carry-in instruction of the above-ground controller 80, the movement control unit 18 performs movement control of the movement trolley 11, the elevator control unit 19 performs movement control of the elevator platform 13, and the advance and retreat control unit 26 advances and retreats the fork 22. control. Thereby, the travelling trolley 11 moves to the target position of the lifting platform 13, and the lifting platform 13 is raised and lowered to the target position of the fork 22 for forward and backward movement, as shown in FIG. 3B. The article storage section 98 of the article storage rack 97 is extended to the article storage section 98. After the container 90 is unloaded from the article storage section 98, the fork 22 is contracted and moved from the article storage section 98 to the turntable 21 as shown in FIG. 3A. In the crane control device 17, based on the carry-out instruction from the above-ground controller 80, the movement control unit 18 performs movement control of the movement trolley 11, the elevator control unit 19 performs movement control of the elevator platform 13, and the advance and retreat control unit 26 advances and retreats the fork 22. control. Thereby, the traveling trolley 11 moves to the target position of the lifting platform 13, and the lifting platform 13 is raised to the target position of the fork 22 for forward and backward movement. As shown in FIG. 3B, the fork 22 moves from the rotary table 21 to the article storage rack 97. The storage unit 98 is extended until the container 90 stored in the article storage unit 98 is retrieved by the fork 22. As shown in FIG. 3A, the fork 22 on which the container 90 is placed is supported from the article storage unit 98 to the turntable 21. Until the contraction movement.

Next, the forward / backward control of the fork 22 by the forward / backward control unit 26 will be described. The forward / backward control unit 26 controls the drive of the forward / backward electric motor 25 in order to move the fork 22 in the order of the acceleration movement, the steady movement, and the deceleration movement during the extension movement and the contraction movement of the fork 22, respectively. Specifically, the forward / backward control unit 26 controls the frequency of a pulse signal input to the forward / backward electric motor 25. The forward / backward control unit 26 increases the frequency of the pulse signal input to the forward / backward electric motor 25 to increase the rotation speed of the forward / backward electric motor 25. Thereby, the fork 22 is accelerated to the predetermined speed with a preset acceleration. The forward / backward control unit 26 keeps the frequency of the pulse signal input to the forward / backward electric motor 25 constant. Thereby, the moving speed of the fork 22 is maintained at the predetermined speed. The forward / backward control unit 26 reduces the frequency of the pulse signal input to the forward / backward electric motor 25 to reduce the rotation speed of the forward / backward electric motor 25. As a result, the fork 22 is decelerated at a predetermined deceleration.

Here, in order to move the stationary fork 22 (mounting body 24), a force larger than the static friction force acting on the fork 22 (mounting body 24) must be applied to the fork 22 (mounting body 24). . Therefore, when the fork 22 (mounting body 24) is accelerated, the advance / retreat control unit 26 applies a static friction force to the fork 22 (mounting body 24) that is larger than the static friction force acting on the fork 22 (mounting body 24). The force method controls the drive of the forward and backward electric motor 25. On the other hand, the forward / backward electric motor 25 rotates in synchronization with the input pulse signal, but in the case of a sudden speed change, or the weight of the container 90 placed on the support body 24 is severely overloaded. In this case, it will not be out of sync with the input pulse signal. Therefore, in order to prevent the out-of-step of the forward and backward electric motor 25, the forward and backward control unit 26 sets the predetermined speed of the fork 22 based on the presence or absence of the container 90 supported on the mounting body 24 and the performance of the forward and backward electric motor 25, The acceleration and deceleration are controlled based on the predetermined speed, acceleration, and deceleration of the set fork 22 (mounting body 24) to control the drive of the electric motor 25 for advancing and retreating.

Here, if the predetermined speed, acceleration, and deceleration of the fork 22 (mounting body 24) are controlled only for the purpose of preventing the out-of-step of the electric motor 25 for advancing and retreating, the fork 22 (mounting) The acceleration during the acceleration movement of the body 24) is increased above a certain speed. In this case, it takes time until the fork 22 is moved at a constant speed at the predetermined speed, and the time required to move the fork 22 between the turntable 21 and the article storage unit 98 becomes longer. Therefore, the advance and retreat control unit 26 controls the advance and retreat electric motor 25 so that the deceleration during the deceleration movement of the fork 22 is greater than the acceleration during the acceleration movement of the fork 22 during the extension movement and the contraction movement of the fork 22, respectively. drive. Specifically, when the fork 22 is decelerated, the advance and retreat control unit 26 controls the drive of the electric motor 25 for forward and backward so as to apply a force greater than the static friction force acting on the fork 22 to the fork 22. The dynamic friction force acting on the fork 22 is smaller than the static friction force acting on the fork 22. Therefore, by applying a force greater than the static friction force to the fork 22 when the fork 22 decelerates, the fork 22 can be fully decelerated. In addition, the deceleration during the deceleration movement of the fork 22 can be made larger than the acceleration during the acceleration movement of the fork 22. More specifically, the rate of reduction per unit time of the frequency of the pulse signal input to the forward / backward electric motor 25 during the deceleration movement of the fork 22 is greater than the input rate to the forward / backward electric motor during the accelerated movement of the fork 22. The method of increasing the frequency of the pulse signal of 25 per unit time is controlled by the frequency of the pulse signal input to the electric motor 25 for advance and retreat during the acceleration movement and deceleration movement of the fork 22.

In addition, the advance and retreat control unit 26 may control the forward and retreat by applying a force equal to the force applied to the fork 22 when the fork 22 is accelerated during the decelerating movement of the fork 22 during the deceleration movement of the fork 22. Driving of the electric motor 25. As described above, in order to move the fork 22 in a stationary state, a force larger than the static friction force acting on the fork 22 must be applied to the fork 22. Furthermore, the dynamic friction force acting on the fork 22 is smaller than the static friction force acting on the fork 22. Therefore, the force applied to the fork 22 during the acceleration movement of the fork 22 is set to be greater than the force of the static friction force acting on the fork 22, and the force applied to the fork 22 during the deceleration movement of the fork 22 is increased. The force is set to the same force as the force applied to the fork 22 during the acceleration movement of the fork 22, thereby making it possible to make the deceleration during the deceleration movement of the fork 22 greater than the acceleration during the acceleration movement of the fork 22. Specifically, the forward / backward control unit 26 decreases the rate per unit time of the frequency of the pulse signal input to the forward / backward electric motor 25 during deceleration of the fork 22 and input to the forward / backward electric motor 25 during acceleration of the fork 22. The frequency of the pulse signal input to the forward / backward electric motor 25 during the acceleration and deceleration movements of the fork 22 is controlled so that the rate of increase in the frequency of the pulse signal per unit time is the same. As described above, by setting the force applied to the fork 22 during the deceleration movement and the acceleration movement of the fork 22 to the same force, the advance and retreat control unit 26 can easily control the forward and backward electric motor 25.

Furthermore, the swing of the fork 22 when moving toward the article storage section 98 side of the article storage rack 97 is greater than when the contraction movement is performed toward the turntable 21 side. Therefore, the forward / backward control unit 26 controls the drive of the forward / backward electric motor 25 so that the deceleration of the decelerating movement during the retracting movement of the fork 22 is greater than the deceleration of the decelerating movement during the elongation movement of the fork 22. Specifically, the rate of decrease per unit time of the frequency of the pulse signal input to the electric motor 25 for advancing and retracting during the decelerating movement during the retracting movement of the fork 22 is greater than the decelerating movement during the elongating movement of the fork 22. The method of reducing the frequency of the pulse signal input to the forward and backward electric motor 25 per unit time is to control the pulse signal input to the forward and backward electric motor 25 during the deceleration movement of the fork 22 during the contraction movement and the extension movement. Frequency of. Similarly, the advance and retreat control unit 26 controls the drive of the forward and backward electric motor 25 so that the acceleration of the acceleration movement during the extension movement of the fork 22 is greater than the acceleration of the acceleration movement during the contraction movement of the fork 22. Specifically, the rate of increase per unit time of the frequency of the pulse signal input to the electric motor 25 for advance and retreat during the acceleration movement during the elongation movement of the fork 22 is greater than the acceleration movement during the retract movement of the fork 22 The method of increasing the frequency of the pulse signal input to the electric motor 25 for advancing and retracting per unit time is a method of controlling the frequency of the pulse signal being input to the electric motor 25 for advancing and retracting during the acceleration movement of the elongation movement and contraction movement of the fork 22. .

Further, the advance / retreat control unit 26 controls the deceleration during the deceleration movement of the fork 22 and the acceleration during the acceleration movement based on the presence or absence of the container 90 placed on the fork 22. Specifically, the advance and retreat control unit 26 controls the electric motor for forward and backward so that the deceleration during the deceleration movement of the fork 22 on which the support container 90 is not placed is greater than the deceleration during the deceleration movement of the fork 22 on which the support container 90 is placed. 25 drives. That is, when the container 90 is carried into the article storage unit 98, the deceleration of the deceleration movement when the fork 22 is retracted and moved is greater than the deceleration of the deceleration movement when the fork 22 is extended and the container 90 is automatically moved. When the article storage unit 98 is carried out, the deceleration of the deceleration movement during the elongation movement of the fork 22 is larger than the deceleration of the deceleration movement when the fork 22 is retracted. In the same manner, the advance and retreat control unit 26 controls such that the acceleration during the acceleration movement of the fork 22 on which the support container 90 is not placed is greater than the acceleration during the acceleration movement of the fork 22 (the placement body 24) on which the support container 90 is placed. Driving of the forward and backward electric motor 25. That is, when the container 90 is carried into the article storage unit 98, the acceleration of the accelerated movement during the contracted movement of the fork 22 is greater than the acceleration of the accelerated movement during the extended movement of the fork 22, and the container 90 is stored from the article. When the unit 98 is carried out, the acceleration of the acceleration movement during the extension movement of the fork 22 is made larger than the acceleration of the acceleration movement during the contraction movement of the fork 22.

As described above, the transfer device 20 cannot increase the acceleration during acceleration of the fork 22 due to the limitation of the electric motor 25 for advancing and retreating the fork 22 (for example, the out-of-step electric motor 25 for advancing and retreating). When the speed is higher than a certain speed, the time required for the entire movement of the fork 22 (the entire extension movement or the contraction movement) can be shortened. In the transfer device 20, the deceleration of the deceleration movement during the contraction movement of the fork 22 (mounting body 24) is greater than the deceleration of the deceleration movement during the extension movement, and the elongation movement of the fork 22 (mounting body 24). The acceleration of the accelerated movement is larger than the acceleration of the accelerated movement during the contracted movement, and therefore, it is possible to reduce the swing of the fork 22 that is extended to a state near the article storage section 98 of the article storage rack 97 as the article transfer position.

In addition, in this embodiment, the transfer device 20 is provided in the stacker crane 10, but it is not limited to this, and it may be provided in an unmanned transfer vehicle, a rail trolley, or the like. In this embodiment, the fork 22 includes a telescopic link mechanism that is mounted on the turntable 21 at one end side, but is not limited thereto. For example, the fork 22 may include a three-stage fork, which includes: A fixed fork portion fixed to the lifting platform 13, a second folk portion that can move forward and backward relative to the fixed fork portion, and a primary folk that can move forward and backward relative to the second fork portion. unit. In this case, the container 90 is placed on and supported by the main fork portion, the second fork portion is advanced and retracted relative to the fixed fork portion, and the main fork portion is advanced and retracted relative to the second fork portion. The forward / backward movement between the elevating platform 13 and the article storage unit 98 of the article storage rack 97. In addition, as a driving means in this case, a member including a pair of pinion gears meshed with a rack fixed to the second fork portion, an electric motor for advancing and retreating the pair of pinion gears by the gear rotation, And two chains connecting one end portion of the fixed fork portion and one end portion of the main fork portion. In addition, the gear is driven forward and backward by the electric motor for advancing and retreating, thereby the pinion rotates, and the pinion gear and the rack are engaged, and the second fork portion moves forward and backward relative to the fixed fork portion. The idler pulley of the second fork part moves and the chain moves the main fork part forward and backward relative to the second fork part, so that the fork is in the article storage section of the lifting platform 13 and the article storage rack 97 Move forward and backward between 98. In the present embodiment, the forward / backward electric motor 25 is a motor that rotates synchronously with the input pulse, such as a stepping motor or a servo motor, but it is not limited to this, as long as it drives the goods at a predetermined speed, acceleration, and deceleration. The fork 22 can be controlled by a motor.

10‧‧‧ Stacker Crane

11‧‧‧ travel trolley

11a‧‧‧ Electric motor for travel

11b‧‧‧Rotary encoder for travel

12‧‧‧Lift

12a‧‧‧ Electric motor for lifting

12b‧‧‧Rotary encoder for lifting

13‧‧‧lifting platform

14‧‧‧ Upper frame

17‧‧‧ Crane control device

18‧‧‧ Movement Control Department

19‧‧‧ Lifting Control Department

20‧‧‧ transfer device

21‧‧‧Turntable (transfer device body)

22‧‧‧ Fork (fork section)

23‧‧‧ connecting rod mechanism

23a‧‧‧Operating Link

23b‧‧‧ rocking connecting rod

24‧‧‧ Mount

25‧‧‧ Electric motor for forward and backward movement (drive part)

26‧‧‧Advance and retreat control department

80‧‧‧ Above-ground controller

90‧‧‧ Container (item)

95‧‧‧ Automatic warehouse

96‧‧‧ travel track

97‧‧‧ article storage rack

98‧‧‧ Article storage department (location of article transfer)

P‧‧‧Upper and lower shaft cores

X‧‧‧ line

FIG. 1 is a front view of a stacker crane including a transfer device of the present invention. FIG. 2 is a side view of a stacker crane including a transfer device of the present invention. FIG. 3A is a plan view of a contracted state of the crane of the transfer device of the present invention. FIG. 3B is a plan view of an extended state of the crane of the transfer device of the present invention. 4 is a control block diagram of a stacker crane provided with a transfer device according to the present invention. In FIG. 5, FIG. 1 is a graph showing the relationship between the speed of advance and retreat of a container in the transfer device of the present invention and time, and FIG. 2 is a graph showing the speed of advance and retreat of a container in the transfer device of the present invention and time. Relationship chart.

Claims (5)

A transfer device includes a fork portion on which a support article is placed, and the article is transferred by moving the fork portion between the transfer device body and the article transfer position, and the feature is: The fork portion performs at least an acceleration movement that accelerates to a predetermined speed and a deceleration movement that decelerates from the predetermined speed, and moves so that the deceleration of the deceleration movement is greater than the acceleration of the acceleration movement. The transfer device according to item 1 of the scope of patent application, wherein the fork portion performs an elongation movement from the transfer device body toward the article transfer position, and from the article transfer position toward the article. The contraction movement of the transfer device body, the elongation movement and the contraction movement are accompanied by at least the acceleration movement accelerated to the predetermined speed, and the deceleration movement decelerated from the predetermined speed, in the same way as during the contraction movement. The deceleration of the decelerating movement is moved in a manner greater than the deceleration of the decelerating movement when the elongating movement is performed. The transfer device according to item 1 of the scope of patent application, wherein the fork portion performs an elongation movement from the transfer device body toward the article transfer position, and from the article transfer position toward the article. The contraction movement of the transfer device body, the elongation movement and the contraction movement are accompanied by at least the acceleration movement accelerated to the predetermined speed, and the deceleration movement decelerated from the predetermined speed, based on the effect of the extension movement. The acceleration of the acceleration movement moves in a manner greater than the acceleration of the acceleration movement when the contraction movement. The transfer device according to any one of claims 1 to 3 in the scope of patent application, comprising: a drive unit that accelerates the fork portion from a stationary state to the predetermined speed, and causes the fork to And decelerating from the predetermined speed, and the driving portion acts on the fork portion when the acceleration movement of the fork portion and the deceleration movement is greater than the acceleration movement of the fork portion. The force of static friction of the fork part. The transfer device according to item 4 of the scope of patent application, wherein the driving portion applies a force equal to the force applied to the fork portion during the accelerated movement during the decelerating movement. .