JP2002046809A - Stacker crane - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stacker crane capable of increasing the traveling speed and accelerating and decelerating speeds thereof to efficiently perform storage and retrieval operations by driving both front and rear traveling wheels. SOLUTION: The front and rear traveling wheels W1 and W2 are formed so as to be driven in synchronous with each other by drive means U1 and U2. Since both front and rear traveling wheels W1 and W2 are driven, the traveling speed and accelerating and decelerating speeds can be increased without producing a large slippage between the wheels and rails 3. Thus, a cycle time at the time of storage and retrieval can be shortened to increase the work efficiency.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stacker crane which is installed in an automatic warehouse or a parts warehouse of a factory, etc., for loading and unloading cargo at a predetermined position on a multi-stage cargo rack. It relates to a modified stacker crane.

[0002]

2. Description of the Related Art As a conventional stacker crane, as described in, for example, Japanese Patent No. 2996036, the driving means for running the entire crane along the lower rail is only one motor with a speed reducer. In most cases, only one of the front and rear traveling wheels is driven.

[0003]

In recent years, there has been a demand for shortening the cycle time at the time of loading and unloading and improving the work efficiency. In order to reduce the cycle time within a limited traveling distance, it is necessary to increase the traveling speed and acceleration / deceleration time of the stacker crane.

[0004] If the running speed of the stacker crane is to be increased in the above-mentioned conventional driving system, the following problems occur. (A) In order to accelerate the acceleration / deceleration time, it is necessary to increase the driving capacity of the motor. However, in this case, the motor and the speed reducer are enlarged, the traveling passage width of the stacker crane is increased, and Effective use of space cannot be achieved. (B) When the acceleration / deceleration time is accelerated, a slip occurs between the drive wheel and the rail, and the wear of the wheel and the rail is accelerated. If it is large, the cost will be high. (C) Since the drive mode by the motor is changed between front wheel drive and rear wheel drive by the forward and backward movements, the running characteristics during start and stop, acceleration and deceleration, and the slip with the rail are slightly changed, and the motor Control system becomes complicated.

The present invention has been made in order to solve the above-mentioned problems, and the traveling speed and acceleration / deceleration time of the crane are increased by using front and rear traveling wheels as two-wheel drive, so that the loading / unloading operation can be efficiently performed. It is an object of the present invention to provide a stacker crane that can perform the operation.

[0006]

In order to achieve the above object, a stacker crane according to the present invention travels on a rail which is laid on the floor in a front-rear direction by a pair of front and rear traveling wheels, and is connected to a loading platform. In a stacker crane for loading and unloading cargo with a side-by-side loading shelf, the front and rear traveling wheels are synchronously driven by driving means. According to this feature, since both wheels are driven by the front and rear traveling wheels, it is possible to increase the traveling speed and acceleration / deceleration time of the stacker crane without causing much slippage between the rails, Cycle time is shortened and work efficiency is improved.

[0007] In the stacker crane of the present invention, it is preferable that the driving means is provided independently for each of the front and rear traveling wheels, and that each driving means is directly connected to the rotating shaft of the front and rear traveling wheels. In this way, the independent driving of the front and rear wheels improves the follow-up performance during high-speed running and acceleration / deceleration running, and enables higher speeds. Further, since the driving force is divided into the front and rear running wheels, the capacity of each driving means (motor) may be halved. Therefore, the size of each driving means (motor) can be reduced, and the width of the passage of the stacker crane can be reduced. Furthermore, since the running wheels are directly connected, there is no expansion or slack compared to belts, etc., and there is no danger of drive unevenness during acceleration / deceleration.Since the structure is simplified, maintenance is unnecessary, and noise is reduced. Is also reduced.

[0008] In the stacker crane of the present invention, it is preferable that the driving means and the traveling wheels are integrally formed as a unit, and this is detachably fixed to the lower part of the front and rear sides of the vertically long rectangular frame. In this way, assembling at the construction site is facilitated, and replacement and maintenance are also simplified.

[0009] In the stacker crane of the present invention, it is preferable that the front and rear driving means be controlled in synchronization by one control device. In this case, the control of both driving means is facilitated and the control system is inexpensive.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a front view showing a relationship between a stacker crane and a load shelf according to an embodiment of the present invention.
3A is a partially enlarged view showing a bogie unit of the stacker crane, and FIG. 3B is a cross-sectional view taken along line AA of FIG.

1 and 2, a stacker crane 1 is shown. The stacker crane 1 is laid on a floor F so as to face the front-rear direction and is mounted on a rail 3 formed in a rectangular cross section. Traveling by a pair of front and rear traveling wheels W1 and W2 provided at a lower portion of a vertically elongated rectangular frame 5, and an upper portion of the frame 5 is guided by a ceiling rail 4 attached to a ceiling C, and travels. 6 and a load 7 between the side-by-side load shelves 2
Entry and exit of goods.

More specifically, the frame 5 comprises masts 5a, 5b and horizontal connecting members 5c, 5d composed of, for example, left and right vertical members, and these members are joined by welding or the like. It is configured as an integrated structure that forms a vertically long rectangle.

Further, on the front and rear side surfaces of the lower end of the frame body 5, running wheels W1 and W2, and drive means U1 and U2 unitized so as to run and drive by a motor 8 and an unillustrated speed reducer, etc., for these wheels. Are attached, and the lower part of the frame 5 is configured as a bogie unit 15.

The loading platform 6 is supported between the masts 5a and 5b by guide rollers 10 arranged vertically so as to be slidable in the vertical direction.

The carrier 6 is taken up by a take-up member 12a of a lifting device 12, guided by sprockets 13 pivotally supported at the upper and lower ends of the frame 5, and before and after hanging down from the sprockets 13, 13. It is suspended by ropes 14, 14 a, 14 b such as a pair of chains or wires, and is configured to be able to move up and down by the operation of the elevating device 12.

On the opposite side of the frame 5 on which the lifting device 12 is provided, there is provided a control unit 16 serving as a control device for controlling the driving means U1, U2, the lifting device 12 and the loading / unloading of the carrier 6. I have.

More specifically, the drive means U1, U2 provided on the front and rear side surfaces of the lower end of the frame 5 have a symmetrical structure, and the mounting plates 18a, 18 joined to the front and rear of the lower end of the frame 5 are provided.
b, the boxes 20a and 20b attached to the boxes 20a and 20b via the flanges 19a and 19b.
Are supported by bearings B1 and B2 through these bearings.
A support shaft 22 for supporting the running wheels W1, W2 between 1 and B2
A speed reducer R which is supported at one end of the support shaft 22 at the extending end and is directly connected to the output shaft of the motor 8;
A box 20 is attached to a side surface of the speed reducer R so as to extend around a support shaft 22 that supports the speed reducer R.
a, Arm 24 Locked to Locking Portion 23 on Side of 20b
And auxiliary wheels 25a, 25b rotatably supported at the lower ends of the boxes 20a, 20b so as to sandwich both side surfaces of the rail 3.

The cart 15 or boxes 20a, 20b
A terminal 28 provided with a plurality of current collecting brushes protrudes from the side surface of the device. A conductive rail 30 for power supply for slidingly contacting the current collecting brush and guiding power and control signals to the control unit 16 is provided in parallel with the rail 3. Has been laid.

Further, the driving means U1 and U2 independently mounted on the front and rear side surfaces of the lower end of the frame 5 are controlled synchronously by one control device.

More specifically, each of the motors 8 of the respective driving means U1 and U2 which are dual-driven is constituted by, for example, a servomotor, and is PID-controlled by each other.

That is, the control unit fetches position data from a laser position detector for detecting the position of the stacker crane 1 into a position controller, detects the number of revolutions of a servomotor controlled by an inverter using an encoder, and obtains the speed data. Is taken into the speed controller, the position data is compared with a reference value by the position controller, and the position error is corrected by the speed controller to correct the rotation speed of the servo motor, thereby performing synchronous control of the two motors. .

The stacker crane 1 according to the present embodiment having the above-described configuration is guided by the rails 3 and the ceiling rails 4 to be able to run in an upright state, and receives a command from an external control device. Thereby, the loading / unloading operation of the load 7 is performed between the loading platform 6 and the side-by-side loading shelf 2.

When the stacker crane 1 travels, the traveling wheels W1 and W2 of the driving means U1 and U2 are driven by motors 8, for example, the traveling wheels W1 and W2.
Is always taken into the position controller as position data from the laser position detector.

If the position data is compared with a reference value by a position controller and an error occurs, the error is corrected by the speed controller to correct the rotation speed of the servo motor and the synchronous control of the motors 8 is performed. Done. Also,
Since these servo motors 8 are controlled by an inverter, acceleration and deceleration can be performed smoothly.

Therefore, the front and rear driving means U1 and U2 are set to 1
By controlling the two control units in synchronization with each other, the control of both drive units is facilitated and the control system is inexpensive.

As described above, according to the present embodiment, since both wheels are driven by the front and rear traveling wheels W1 and W2, the rail 3
It is possible to increase the traveling speed and acceleration / deceleration time of the stacker crane 1 without causing much slippage between them, and the cycle time at the time of loading and unloading is shortened, thereby improving work efficiency.

In addition, the independent driving of the front and rear wheels W1 and W2 improves the follow-up performance during high-speed running and acceleration / deceleration running, thereby enabling higher speed.

Further, since the driving force is divided into the front and rear running wheels W1 and W2, the capacity of each driving means (motor 8) may be halved, so that it can be downsized and the passage width of the stacker crane 1 is reduced. can do.

In addition, since the driving means U1 and U2 are of the type directly connected to running wheels, there is no elongation or slack as compared with a belt or the like, and there is no danger of driving unevenness during acceleration / deceleration, and the structure is simple. This eliminates the need for maintenance and reduces noise.

The driving means U1 and U2 are connected to the traveling wheels W
1, W2 is integrally unitized and detachably fixed to the lower front and rear side surfaces of the vertically long rectangular frame 5, so that assembly at the construction site becomes easy, and replacement and Maintenance is also simplified.

Next, a modification of each driving means will be described.

FIG. 3 is a partial plan view showing a first modification, in which synchronous driving of each driving means is performed by a timing belt.

One traveling wheel W2 of a pair of front and rear traveling wheels W1 and W2 is directly connected via a drive shaft J1 to a speed reducer R of a servo motor 8 which is controlled by an inverter. A pulley 33a having the same diameter is attached to a driven shaft J2 that supports the other traveling wheel W1 and has a pulley 33a attached thereto.

A timing belt 34 is suspended from the timing pulleys 33a and 33b, and one of the timing belts 34 is adjusted so that the tension roller 32 is pressed to keep the tension of the timing belt 34 constant.

Therefore, when one traveling wheel W2 is driven by the servo motor 8, the other traveling wheel W1 is also rotationally driven by the timing belt 34 at a synchronous speed.

Next, FIG. 4 is a partial plan view of a second modified example, in which synchronous driving of each driving means is performed through a pair of umbrella wheels.

One traveling wheel W2 of a pair of front and rear traveling wheels W1 and W2 is directly connected via a drive shaft J1 to a speed reducer R of a servomotor 8 controlled by an inverter. A gear 36a is mounted, and a bevel gear 36b having the same number of teeth is fixed to the other traveling wheel W1.

The pair of bevel gears 36a and 36b include:
The pair of bevel gears 37a and 37b mesh with each other via the connecting shaft 35, and the pair of bevel gears 37a and 37b are pressed with a predetermined pressure in the meshing direction (the direction of the arrow) to reduce backlash.

When one of the traveling wheels W2 is driven by the servo motor 8, the other traveling wheel W1 is also driven by the bevel gears 36a, 36b and 37a, 37.
b is driven to rotate at a synchronous speed.

As described above, in the first modified example and the second modified example, since the servo motor 8 of one of the driving means is controlled by the inverter, acceleration and deceleration can be performed smoothly.

Although the embodiments of the present invention have been described with reference to the drawings, the specific configuration is not limited to these embodiments, and even if there are changes and additions without departing from the gist of the present invention. Included in the invention.

[0042]

According to the present invention, the following effects can be obtained.

(A) According to the first aspect of the present invention, since both wheels are driven by the front and rear traveling wheels, the traveling speed and acceleration / deceleration time of the stacker crane do not cause much slip between the rails. Can be made faster, the cycle time at the time of loading and unloading is shortened, and the work efficiency is improved.

(B) According to the second aspect of the present invention, the independent driving of the front and rear wheels improves the follow-up performance during high-speed running and acceleration / deceleration running, thereby enabling higher speed. Further, since the driving force is divided into the front and rear running wheels, the capacity of each driving means (motor) may be halved. Therefore, the size of each driving means (motor) can be reduced, and the width of the passage of the stacker crane can be reduced. Furthermore, since the running wheels are directly connected, there is no expansion or slack compared to belts, etc., and there is no danger of drive unevenness during acceleration / deceleration.Since the structure is simplified, maintenance is unnecessary, and noise is reduced. Is also reduced.

(C) According to the third aspect of the present invention, assembling in a construction factory becomes easy, and replacement and maintenance become easy.

(D) According to the fourth aspect of the invention, the control of both driving means is facilitated and the control system is inexpensive.

[Brief description of the drawings]

FIG. 1 is a front view showing a relationship between a stacker crane and a load shelf according to an embodiment of the present invention.

FIG. 2A is a partially enlarged view showing a bogie portion of a stacker crane, and FIG. 2B is a sectional view taken along line AA of FIG.

FIG. 3 is a plan view of a first modified example in which synchronous driving of each driving unit is performed by a timing belt.

FIG. 4 is a plan view of a second modified example in which synchronous driving of each driving unit is performed via a pair of umbrella wheels.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Stacker crane 2 Packing shelf 3 Rail 4 Ceiling rail 5 Frame body 5a, 5b Mast 5c, 5d Vertical connection member 6 Loading platform 7 Load 8 Servo motor 10 Guide roller 12 Elevating device 12a Winding member 13 Sprocket 14 Cable line 15 Truck section 16 Control unit 18a, 18b Mounting plate 19a, 19b Flange 20a, 20b Box 22 Support shaft 23 Locking portion 24 Arm 25a, 25b Auxiliary wheel 28 Terminal 30 Conductive rail 32 Tension roller 33a, 33b Timing pulley 34 Timing belt 35 Connecting shaft 36a, 36b bevel gear 37a, 37b bevel gear B1, B2 bearing C ceiling F floor J1 drive shaft J2 driven shaft R reducer U1, U2 drive means W1, W2 running wheel

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Shinichiro Tomita 2-7-18 Kitako, Nishi-ku, Yokohama-shi, Kanagawa F-term in Okamura Works (reference) 3F022 FF01 JJ09 MM01 MM02 MM11 MM57 3F333 AA04 AB08 BF04 BF06 BG01 CA12 DA02 DA03 FA20

Claims (4)

[Claims] 1. A stacker crane that travels on a rail laid on a floor surface in a front-rear direction by a pair of front and rear traveling wheels to load and unload a load between a bed and a side-by-side load shelf. A stacker crane wherein the front and rear traveling wheels are driven synchronously by a driving means. 2. The stacker crane according to claim 1, wherein the driving means is provided independently for each of the front and rear traveling wheels, and each driving means is directly connected to a rotating shaft of the front and rear traveling wheels. 3. The stacker crane according to claim 1, wherein the drive means and the traveling wheels are integrally formed as a unit, and the unit is detachably fixed to lower front and rear side surfaces of the vertically elongated frame. 4. The stacker crane according to claim 2, wherein the front and rear drive units are controlled in synchronization by one control device.