JPH10291639A - Elevating conveyer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce time required for one conveying, by setting acceleration and deceleration to optimal value according to unbalance weight derived from difference between elevating conveyer's total weight and total balance weight and summation of the elevating conveyer's total weight and the total balance weight. SOLUTION: A controller 13 sets acceleration of an elevating conveyer just after beginning of elevation and deceleration just before a predetermined stopping position on the basis of either a first parameter which is derived from elevating conveyer's total weight and previously known unbalance weight in relation to the elevating conveyer, or a second parameter 2 determined by summation of the elevating conveyer's total weight and the total balance weight. Thus, the controller 13 outputs motion instructing pulse to an amplifier 12 so that when the first parameter or the second parameter is small, acceleration and deceleration are increased respectively comparing the case that the first or second parameter is large.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lifting transport device.

[0002]

2. Description of the Related Art This type of lifting and lowering transport device is frequently used in, for example, an automatic warehouse system. The automatic warehouse system is suitable for storing and managing conveyed articles such as parts, semi-finished products, and finished products, and the conveyance of conveyed articles is almost fully automated. For this purpose, the lifting / lowering transport device is provided with a lifting / lowering conveyor provided with a transport device for transporting the transported material in the horizontal direction, and can transfer the transported material between the vertical / lower conveyor and the floor conveyors provided in each of the plurality of layers. Like that.

[0003] An induction motor has been used as a lifting drive source of a lifting conveyor. The induction motor is combined with an inverter device for performing operation and stop control including speed control, and is provided with a control system of the inverter device. The control system has, besides a controller also called a sequencer, an operation panel equipped with a keyboard for instructing start-up and stop of the device and for inputting data such as in which hierarchy the transfer of the conveyed goods is performed. ing.

[0004] For example, it is assumed that data such as receiving a conveyed article from a first-floor floor conveyor and passing it to a third-floor floor conveyor is input through this operation panel. In this case, referring to FIG. 9, lifting conveyor 20 stops at a predetermined stop position on the first floor, and when this is detected, floor conveyor 30 on the first floor transfers a conveyed object (not shown) into lifting conveyor 20. The conveyor 20 is driven so as to be conveyed.
Is also driven in a direction for receiving the conveyed object.
When it is detected that the conveyed object has been received, the elevating conveyor 2
0 rises to the third floor and stops at a predetermined stop position. When this stop is detected, the conveying device 21 of the elevating conveyor 20
Is driven in a direction to discharge the conveyed article to the third-floor floor conveyor 40, and the third-floor floor conveyor 40 is also driven in a direction for receiving the conveyed article. When the transfer is completed, the lifting conveyor usually returns to the floor where the transfer was started, in the above case, returns to the first floor and stops.

[0005] By the way, in the conventional lifting conveyor,
Control is performed to accelerate at a certain acceleration from the start of ascent and descent, to run at a constant speed when reaching a certain speed, and to stop at a predetermined stop position while decelerating at a certain deceleration before a predetermined stop position. ing. This will be described with reference to FIG.

In FIG. 10, the allowable acceleration of the lifting conveyor 20 is uniquely set in advance based on the maximum total weight which is the sum of its own weight and the maximum loading weight.
For this reason, when a load is loaded from the first floor and rises to the third floor, regardless of the weight of the load, the vehicle accelerates at a certain acceleration Ac after starting traveling and reaches a predetermined speed Vc. Then, the vehicle travels at the speed Vc, and stops at a predetermined stop position while decelerating at a deceleration Ac before the predetermined stop position on the third floor. Even when the vehicle returns from the third floor to the first floor, the vehicle accelerates at a certain acceleration Ac after starting to ascend and descend when the vehicle reaches a predetermined speed Vc, as in the case of ascending, even though the vehicle travels in an empty state. Traveling at speed Vc,
The vehicle stops at the predetermined stop position while decelerating at a certain deceleration Ac before the predetermined stop position on the first floor.

The above-described lifting control is the same regardless of whether the moving distance of the lifting conveyor to the target position, that is, the distance between the layers for transporting the goods is long or short.

[0008]

In the above-described control system, even when the elevator is empty, the vehicle travels at the same speed as the vehicle with the maximum load, that is, all vehicles run at the same acceleration and deceleration. Time and deceleration time are wasted, and the round-trip time Tt 'required for one transfer is restricted.

[0009] Considering the case of short-distance movement from the first floor to the lower level and the case of long-distance movement from the first floor to the higher level, the stopping time (moving time of the conveyed object) with respect to the moving time of the elevator is considered. (The time required for relocation is assumed to be constant at all floors) is greater in the case of moving to a lower hierarchy. Considering this from the motor load factor, it means that the motor load factor is lower when moving to a lower hierarchy than when moving to a higher hierarchy. In other words, in the case of moving to a lower level, the ability of the motor is not effectively used.

An object of the present invention is to shorten the time required for one transfer by allowing the acceleration and deceleration to be set to optimum values according to the presence or absence of a conveyed object to the lifting conveyor. It is an object of the present invention to provide an ascending / descending transport device capable of performing the following.

Another object of the present invention is to make it possible to set the acceleration and deceleration to optimum values according to the moving distance of the elevating conveyor to the target position, so that it can be used for both short distance movement and long distance movement. It is an object of the present invention to provide an ascending / descending transport device that can effectively use the capability of a motor.

[0012]

According to a first aspect of the present invention, there is provided an elevating conveyor provided with a conveying device for conveying a conveyed object in a horizontal direction, and the elevating conveyor and the elevating conveyor are provided on each of a plurality of levels. In an elevating / lowering transporting apparatus that transports a transported object so that the transported object can be transferred to and from a floor conveyor, a servomotor is provided as an elevation drive source of the elevation conveyor, and the servomotor is controlled to control the elevation of the elevation conveyor. A control system for performing elevation control is provided, and the control system includes:
The acceleration immediately after the start of lifting of the lifting conveyor, and the deceleration before a predetermined stop position,
A first parameter by an unbalanced load defined by a difference between a total weight of the lifting conveyor and a previously known balance weight total weight attached to the lifting conveyor, a total weight of the lifting conveyor and a total weight of the balance weight, Having a function of setting the acceleration and the deceleration when the first parameter or the second parameter is smaller than when the first parameter or the second parameter is larger. There is provided an ascending / descending transport device characterized in that each is made larger.

[0013] According to the second aspect, there is provided an elevating conveyor provided with a conveying device for conveying the conveyed object in the horizontal direction, and the conveyed object is transferred between the elevating conveyor and the floor conveyors provided at each of a plurality of levels. In a lifting and lowering transport device that transports a transported article so that it can be delivered, a servomotor is provided as a lifting drive source of the lifting and lowering conveyor, and a control system that controls the servomotor to perform lifting and lowering control of the lifting and lowering conveyor is provided, The control system sets the acceleration immediately after the lifting conveyor starts moving up and down, and the deceleration immediately before a predetermined stop position, based on the moving distance to the target position of the lifting conveyor, which can be known in advance. The acceleration and the deceleration are larger when the moving distance is shorter than when the moving distance is longer. Lifting transport apparatus is provided, characterized in that the the to.

According to the third aspect, there is provided an elevating conveyor provided with a conveying device for conveying the conveyed object in a horizontal direction, and the conveyed object is transferred between the elevating conveyor and the floor conveyors provided at each of a plurality of levels. In a lifting and lowering transport device that transports a transported article so that it can be delivered, a servomotor is provided as a lifting drive source of the lifting and lowering conveyor, and a control system that controls the servomotor to perform lifting and lowering control of the lifting and lowering conveyor is provided, The control system is configured to determine the acceleration immediately after the lifting conveyor starts moving up and down and the deceleration immediately before a predetermined stop position, respectively, with the total weight of the lifting conveyor and a known balance weight attached to the lifting conveyor. A first parameter based on an unbalanced load defined by a difference from a total weight; a total weight of the lifting conveyor; Has a function to set based on any one of the second parameter defined by the sum of the bets total weight,
When the first parameter or the second parameter is small, the acceleration and the deceleration are respectively increased as compared with the case where the first parameter or the second parameter is large, and the control system further includes: A function to set the deceleration before the predetermined stop position based on the moving distance to the target position of the elevating conveyor which can be known in advance, and when the moving distance is small, There is provided an ascending / descending transport device, wherein the acceleration and the deceleration are respectively made larger than when the moving distance is long.

In the first and third embodiments, the total weight of the elevating conveyor is determined by the control system and the weight of a conveyed object to be conveyed, which is input and set by an operator. The control system is further configured to detect the load current of the servomotor that is calculated using the weight of the lifting conveyor in a state or is in a stopped state during operation. The difference between the total weight of the lifting conveyor and the total weight of the balance weights, that is, the weight of the conveyed object is calculated from the unbalanced load, and the weight of the empty lifting conveyor registered in advance is added to the calculation result. Then, the total weight of the lifting conveyor may be calculated.

In the above-mentioned second and third embodiments, the moving distance of the lift conveyor is determined by the control system in the hierarchy at which the transfer of the conveyed goods set by the operator is performed and the current position of the lift conveyor. Is calculated from the hierarchy.

[0017]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a block diagram showing a control system for controlling the lifting and lowering of a lifting conveyor in the lifting and lowering transport device according to the present invention. In the present invention, the servomotor 10 is used as a lifting drive source of the lifting conveyor. As is well known, the servo motor 10 includes an encoder 11, and the encoder 11 outputs a detection pulse corresponding to the rotation speed of the servo motor 10. This detection pulse is used as a position feedback signal indicating the current position of the elevating conveyor, and is given to the amplifier 12. That is, a reference position (for example, the uppermost movable position) is previously determined for the lifting conveyor,
The encoder 11 sets the reference position at 0, and outputs a detection pulse corresponding to the rotation speed of the servomotor 10, that is, the moving distance of the elevating conveyor, as a position feedback signal.

The detection signal of the encoder 11 attached to the servo motor 10 may be used as it is, or may be corrected. This is caused by the expansion of the wire hanging the lifting conveyor due to thermal expansion or applied load, the slip between the wire and the pulley that suspends it, and the distortion including elastic distortion of the entire structure. , Servo motor 1
This is because the detection signal of the encoder 11 attached to 0 may include an error. One way to correct this error is
The up-and-down movement of the elevating conveyor is converted into a rotational motion, and this rotation is detected by an encoder other than the encoder 11, a comparison is made between this detection signal and a rotation detection signal of the encoder 11, and a movement command described later is made based on the comparison result. This is realized by adding a correction to the pulse. That is, the difference between the outputs of the two encoders is detected, and this difference is added to or subtracted from the movement command pulse.

The controller 13 supplies a movement command pulse to the amplifier 12 in accordance with input data from an operation panel 14 having a display unit and a data input unit such as a keyboard.
As input data, in addition to instructions for starting and stopping the device,
It is necessary to have at least a level at which the goods should be delivered, and other values such as the total weight of the goods are input. The controller 13 also registers the distance from the reference position to the stop position of each floor as position data, and also registers the weight of the lifting conveyor in an empty state and the like.

For example, when input data for conveying a conveyed article from the first floor to the third floor is given, the controller 13
Since the above location data is registered in advance,
The controller 13 can easily calculate the travel distance from the first floor to the third floor.
A movement command pulse corresponding to the distance required to move to the floor is given to the amplifier 12.

In particular, the controller 13 according to the first embodiment of the present invention uses the total weight of the lifting conveyor and the deceleration just before the predetermined stop position of the lifting conveyor to determine the acceleration immediately after the start of the lifting and lowering of the lifting conveyor, respectively. The difference between the total weight of the balance weight, which can be known in advance, that is, the first parameter based on the unbalanced load, or the second parameter defined by the sum of the total weight of the lifting conveyor and the total weight of the balance weight. Has a first function of setting based on the With this first function, the controller 13 allows the first or the second
When the parameter is small, a movement command pulse that increases the acceleration and the deceleration is output as compared to when the parameter is large.

Next, the controller 13 according to the second embodiment of the present invention comprises a lifting conveyor capable of knowing in advance the acceleration immediately after the lifting conveyor starts lifting and the deceleration just before a predetermined stop position. Has a second function of setting based on the moving distance to the target position. According to the second function, a movement command pulse is output such that the acceleration and the deceleration are increased when the movement distance is small as compared with when the movement distance is large.

First, FIGS. 2 and 3 show the first embodiment.
This will be described with reference to FIG. FIG. 2 shows a case where the lifting conveyor 20 is on the first floor and a conveyed article (not shown) is conveyed from the first floor to the third floor. In the case where such conveyance is repeatedly performed, the conveyed material is transferred from the floor conveyor 30 on the first floor to the conveyance device 21 in the elevating conveyor 20, and when the reception is completed, the conveyed material is elevated and stopped at a predetermined stop position on the third floor. It is transferred to the floor conveyor 40 on the third floor by the device 21. When this is completed, the elevating conveyor 20 descends and stops at a predetermined stop position on the first floor, and the conveyed goods are transferred from the floor conveyor 30 on the first floor to the elevating conveyor 20 again. Hereinafter, the above operation is repeated.

In such a case, the total weight of the lifting conveyor 20 is large when ascending, and small when descending. In other words, when ascending, the first and second parameters are large, and when descending, the second parameter is small. by the way,
In the controller 13, an allowable acceleration with respect to the maximum loading weight of the lifting conveyor 20 is set in advance. The controller 13 calculates the acceleration and deceleration A1 during the ascending from the first or second parameter in the state where the article is loaded and the first or second parameter in the empty state based on the allowable acceleration with respect to the maximum load weight. And the acceleration and deceleration A2 (A2> A1) at the time of descent. Of course,
The maximum value of the acceleration calculated in this way is a value that does not exceed the allowable acceleration. After the acceleration starts, the speed V
The vehicle travels at a constant speed at a speed c. This speed Vc is a rated speed determined for this type of elevating conveyor as in the prior art. In order to calculate the first or second parameter, it is necessary to know the total weight of the lifting conveyor 20. This method will be described later.

In order to make the acceleration and the deceleration variable as described above, in the first embodiment, the controller 13 changes the frequency of the movement command pulse, and, when it comes to acceleration, starts and then reaches the speed Vc. Acceleration time up to,
The deceleration is defined by the deceleration time from the start of deceleration to the stop. Therefore, the shorter the acceleration time, the greater the acceleration. When predetermined data is actually input to the operation panel 14, the controller 13 creates a traveling pattern of the elevating conveyor from the data to a target position of the elevating conveyor, that is, a hierarchy to which a conveyed object is to be conveyed. A movement command pulse is output based on the running pattern. This running pattern is the distance to the target position,
It is equivalent to the distance traveled during the acceleration time at a certain acceleration, the distance traveled during the travel time at a constant speed, and the distance traveled during the deceleration time at a certain deceleration. , Acceleration time, constant speed traveling time, and deceleration time. Usually, the acceleration time and the deceleration time are made equal,
It can be different.

FIG. 4 shows the relationship between an example of the movement command pulse and the speed of the elevating conveyor. Also, as is well known, the servo motor has an A phase as shown in FIG.
Driving is performed by a two-phase pulse composed of the B phase, and normal rotation and reverse rotation can be performed by shifting the phase therebetween.

As described above, the controller 13
In the case of FIG. 2, the acceleration time and deceleration time T1 and the constant speed traveling time T2 for obtaining the acceleration and deceleration A1 at the time of ascending based on the acceleration and deceleration A1 and A2, and the acceleration and deceleration A2 at the time of descent. Acceleration time and deceleration time T for obtaining
3 and the constant speed traveling time T4 are output as a movement command pulse.

Returning to FIG. 1, the amplifier 12 controls the position feedback signal from the encoder 11 and the controller 13.
And the power command is supplied from the motive power source, and the current value to be supplied to the servomotor 10 is determined according to the deviation between the position feedback signal and the motion command pulse. Drive with the determined current. The servo motor 10 rotates with a torque corresponding to the current value to drive the lifting conveyor.

[0029] In FIG. 3, the lift conveyor 20, starting from the time t ₀ is determined by the acceleration time T1 acceleration A1
In acceleration while elevated, reaching speed Vc at time t ₁ moves to constant speed running at the speed Vc. When the constant-speed running time T2 has elapsed, it starts to decelerate at time t _2, the deceleration time T
It stops at time t ₃ while decelerating at the deceleration A1 determined by the 1 in the third floor of the target position. When the transfer of goods is completed,
It accelerated with determined acceleration A2 at the start to acceleration time T3 descends while at time t _4, reaches the speed Vc at time t ₅ moves to constant speed running at the speed Vc. When the constant-speed running time T4 has elapsed, starts to decelerate at time t _6, time t ₇ while decelerating at the deceleration A2 determined by the deceleration time T3
At the target position on the first floor.

As described above, by making the acceleration and the deceleration variable in accordance with the above-mentioned first or second parameter, the time Tt required for one round trip between the first floor and the third floor becomes: Since the acceleration time and the deceleration time at the time of descent can be shortened, the time Tt ′ described with reference to FIG. 10 can be shortened.

By the way, the first method for knowing the total weight of the lifting conveyor 20 is as follows. When the operator inputs the weight per conveyed object from the operation panel 14, this input data is registered in the controller 13 in advance. The controller 13 can calculate and know the sum of the weight of the lifting conveyor 20 and the weight of the lifting conveyor 20 in the empty state.

As a second method, it can be calculated from the load current of the servo motor 10. That is, a load is constantly applied to the servomotor during its operation, and the value of the load current flowing through the servomotor changes according to the change in the load. In particular, when the elevator is stopped at a certain position, a load current corresponding to the difference between the total weight of the elevator and the total weight of the balance weights, that is, an unbalanced load is flowing. FIG. 6 (a) shows the load current value when the elevator is stopped at a position where there is an empty elevator, and FIG. 6 (b) shows a state where the elevator is stopped at a position where there is an elevator with a load. And the load current value indicates I2. The load current value I2 is equal to the load current value I1.
To the total weight of the conveyed product. Therefore,
The total weight of the conveyed goods can be calculated by (I2 -I1), and the total weight of the elevating conveyor 20 can be known by adding the weight of the previously known empty elevating conveyor 20 to this.

Usually, the amplifier 12 is often provided with a torque monitor for a servo motor. This torque monitor detects a torque by detecting a load current flowing through a servomotor. Therefore, by feeding back the load current in the stopped state detected by the torque monitor to the controller 13, the total weight of the lifting conveyor can be calculated. It should be noted that whether or not the elevator is in a stopped state is determined by transmitting a position feedback signal to the controller 1.
3 to detect the presence or absence of the change. In this way, the total weight of the lifting conveyor can be calculated without providing a sensor for detecting the weight of the conveyed object, particularly on the lifting conveyor or the floor conveyor.

Next, a second embodiment will be described with reference to FIGS. FIG. 7 shows a case where the lifting conveyor 20 is on the first floor and a conveyed article (not shown) is conveyed from the first floor to the second floor (FIG. A) and a case where the conveyed article is conveyed from the first floor to the fourth floor (FIG. B). Is shown. When such transport is repeated,
A conveyed object is transferred from a first-floor floor conveyor (not shown) to a transfer device 21 in an elevating conveyor 20. When the transfer is completed, the conveyed material rises and stops at a predetermined stop position on the first or third floor. To the first or third floor conveyor. When this is completed, the elevating conveyor 20 descends and stops at a predetermined stop position on the first floor, and the conveyed goods are transferred to the elevating conveyor 20 again from the first floor floor conveyor.
Hereinafter, the above operation is repeated.

In such a case, the ratio of the stop time (the time required for transfer of the conveyed goods, which is constant on all floors) to the movement time of the elevating conveyor 20 is 2 to 1 floor.
The movement of the distance L2 to the floor is larger than the movement of the distance L1 from the first floor to the fourth floor. From the viewpoint of the motor load factor, when the motor load factor is moved from the first floor to the second floor,
It is lower than when moving from the first floor to the fourth floor. Therefore, in the second embodiment, even when moving from the first floor to the second floor, as in the case of moving from the first floor to the fourth floor, in order to effectively use the capacity of the motor, it is necessary to move to a lower level. The greater the movement, the greater the acceleration from the start and the deceleration at the time of stop.

The controller 13 includes a lifting conveyor 20.
As described above, the allowable acceleration for the maximum load weight of the controller 13 is set in advance.
Calculates acceleration and deceleration at the time of ascending and descending from the moving distance of the up-and-down conveyor 20 currently conveyed within a range not exceeding the allowable acceleration. For example, when moving from the first floor to the second floor, acceleration and deceleration A11 are calculated, and when moving from the first floor to the fourth floor, acceleration and deceleration A21 (A21> A11) are calculated. Here, the total weight of the lifting conveyor 20 in the first embodiment described above is not considered.

In order to make the acceleration and the deceleration variable as described above, the controller 13 changes the frequency of the movement command pulse as described in the first embodiment. The acceleration time until reaching Vc and the deceleration are defined by the deceleration time from the start of deceleration to the stop. Therefore, when predetermined data is input to the operation panel 14, the controller 13 creates a traveling pattern of the elevating conveyor up to the target position of the elevating conveyor, that is, the level where the conveyed goods are to be transported, from this data. And outputs a movement command pulse based on. This travel pattern includes the distance to the target position, the distance to move during the acceleration time at a certain acceleration, the distance to move during the travel time at a constant speed, and the distance to move during the deceleration time at a certain deceleration. And can be expressed by acceleration time, constant speed traveling time, and deceleration time.

As described above, in the case of FIG. 7A, the controller 13 controls the acceleration time and the deceleration time T11 for obtaining the acceleration and the deceleration A11 based on the acceleration and the deceleration A11 and the constant speed traveling. The time T12 is calculated. On the other hand, in the case of FIG. 7B, the acceleration time, the deceleration time T21, and the constant speed traveling time T22 for obtaining the acceleration and the deceleration A21 are expressed as movement command pulses and output.

[0039] In FIG. 8 (a), if the transport from the first floor to the second floor, the lift conveyor 20 is elevated while accelerating at an acceleration A11 that starting from the time t ₁₁ is determined by the acceleration time T11, the time t ₁₂ To reach the speed Vc, and shift to the constant speed running at this speed Vc. When the constant speed traveling time T12 elapses, the time t
Starts to decelerate at _13, stopped at the second floor of the target position at time t ₁₄ while decelerating at the deceleration A11 determined by deceleration time T11. When the transfer of the conveyed object is completed, the transfer object descends in the same pattern as described above.

[0040] In FIG. 8 (b), the case of conveyance from the first floor to the fourth floor, the lift conveyor 20 is elevated while accelerating at an acceleration A21 that starting from the time t ₂₁ is determined by the acceleration time T21, the time t ₂₂ To reach the speed Vc, and shift to the constant speed running at this speed Vc. When the constant speed traveling time T22 elapses, the time t
Starts to decelerate at _23, and stops at the target position of the fourth floor at time t ₂₄ while decelerating at the deceleration A21 determined by deceleration time T21. When the transfer of the conveyed object is completed, the transfer object descends in the same pattern as described above.

As described above, in the second embodiment, the acceleration and the deceleration are made variable in accordance with the moving distance per one movement of the lifting / lowering conveyor, so that the ability of the servomotor is effective even when the moving distance is short. Can be used for This means that the total work time can be shortened especially when the transfer work with a short moving distance is repeated.

In the first and second embodiments, FIG.
Although the control system described above has the first and second functions individually, this control system may have the first and second functions. In this case, the controller 13 creates a traveling pattern using the first and second functions based on the input data, and determines which one of the traveling patterns is more efficient to drive. One or the other may be selected. Determination of efficiency
It is conceivable to perform the operation depending on the magnitude of the acceleration. That is, it is only necessary to select a larger one of the acceleration and the deceleration within the range of the allowable acceleration. Separately, when a conveyed object is mounted on the elevating conveyor, the second function, that is, acceleration and deceleration calculated based on the moving distance of the elevating conveyor, is employed, and the elevating conveyor is driven in an empty state. in case of,
The first function, that is, the acceleration and deceleration calculated based on the first or second parameter may be adopted. As still another method, the following method may be used.
First, acceleration and deceleration are calculated by the first function. The acceleration and deceleration calculated here need to be values that can withstand the transfer operation in the continuous operation to the top floor. Next, based on the acceleration and deceleration obtained by the first function,
By calculating the final acceleration and deceleration using the second function from the floor position where the actual reciprocating operation is performed, it is possible to perform the operation that maximizes the performance of the servomotor.

[0043]

As described above, according to the present invention, a servomotor is used as a drive source of an elevating conveyor, and an unbalanced load or an elevating conveyor due to the difference between the total weight of the elevating conveyor and the total weight of the balance weight is used. Acceleration and deceleration can be set to optimal values according to the sum of the total weight of the
The time required for one transfer can be reduced.

Further, the acceleration and deceleration can be set at optimum values according to the moving distance of the lifting conveyor, so that the ability of the motor can be effectively used for both short-distance movement and long-distance movement. In particular, in the case of a short distance movement, the working time can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a control system for performing elevation control of an elevation conveyor in an elevation transport device according to the present invention.

FIG. 2 is a diagram for explaining control of a lifting conveyor according to the first embodiment of the present invention.

FIG. 3 is a view for explaining a traveling pattern of a lifting conveyor according to the first embodiment shown in FIG. 2;

4 is a diagram showing a relationship between a movement command pulse output from the controller shown in FIG. 1 and a speed of a lifting conveyor.

FIG. 5 is a diagram illustrating an example of a pulse supplied to the servomotor illustrated in FIG. 1;

FIG. 6 is a current waveform diagram for explaining a method of calculating the total weight of the lifting conveyor from the load current of the servomotor in the first embodiment of the present invention.

FIG. 7 is a diagram for explaining control of a lifting conveyor according to a second embodiment of the present invention.

FIG. 8 is a view for explaining a traveling pattern of the lifting conveyor according to the second embodiment shown in FIG. 7;

FIG. 9 is a diagram for explaining control of a conventional elevating conveyor.

FIG. 10 is a view for explaining a running pattern of the conventional elevating conveyor shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Servo motor 11 Encoder 12 Amplifier 13 Controller 14 Operation panel 20 Elevating conveyor 21 Conveying device 30, 40 Floor conveyor

Claims (9)

[Claims] 1. A lifting conveyor provided with a transfer device for transferring a conveyed object in a horizontal direction, wherein the conveyed object is conveyed between the elevating conveyor and floor conveyors provided on a plurality of levels, respectively. In a lifting and lowering transport device that transports objects, a servomotor is provided as a lifting and lowering drive source of the lifting and lowering conveyor, and a control system that controls the servomotor to perform lifting and lowering control of the lifting and lowering conveyor is provided. The acceleration immediately after the start of lifting and lowering of the lifting conveyor and the deceleration just before a predetermined stop position are determined by the difference between the total weight of the lifting conveyor and the total weight of known balance weights attached to the lifting conveyor, respectively. The first parameter based on the specified unbalance load, which is defined by the sum of the total weight of the lifting conveyor and the total weight of the balance weights. A function to set the acceleration and the deceleration when the first parameter or the second parameter is smaller than when the first parameter or the second parameter is larger. An ascending / descending transport device characterized in that: 2. The lifting and lowering transport device according to claim 1, wherein
The total weight of the elevating conveyor is calculated using the weight of the conveyed object to be conveyed input and set by an operator and the weight of the elevating conveyor in an empty state registered in advance in the control system. Elevating transport device. 3. The lifting and lowering transport device according to claim 1, wherein
Means for detecting a load current of the servomotor in a stopped state during operation, wherein the control system determines a difference between a total weight of the lifting conveyor and a total weight of the balance weight based on the detected load current. That is, the weight of the conveyed object is calculated from the unbalanced load, and the total weight of the elevating conveyor is calculated by adding the weight of the elevating conveyor in an empty state registered in advance to the calculation result. Elevating transport device. 4. A lifting conveyor provided with a transport device for transporting a transported product in a horizontal direction, and transporting the transported product so that the transported product can be transferred between the elevator and a plurality of floor conveyors. In a lifting and lowering transport device that transports objects, a servomotor is provided as a lifting and lowering drive source of the lifting and lowering conveyor, and a control system that controls the servomotor to perform lifting and lowering control of the lifting and lowering conveyor is provided. Acceleration immediately after the start of lifting of the lifting conveyor, and the deceleration in front of a predetermined stop position, respectively, has a function to set based on the moving distance to the target position of the lifting conveyor that can be known in advance, When the moving distance is small, the acceleration and the deceleration are made larger than when the moving distance is large. Lifting and lowering transport device. 5. The lifting and lowering transport device according to claim 4, wherein
The moving distance of the lifting conveyor is, in the control system,
An ascending / descending transport device, which is calculated from a tier at which a transported object is set and inputted by an operator and a current tier of the ascending / descending conveyor. 6. A lifting conveyor provided with a transport device for transporting a transported product in a horizontal direction, and transporting the transported product so that the transported product can be transferred between the lifting and lowering conveyor and floor conveyors provided at each of a plurality of levels. In a lifting and lowering transport device that transports objects, a servomotor is provided as a lifting and lowering drive source of the lifting and lowering conveyor, and a control system that controls the servomotor to perform lifting and lowering control of the lifting and lowering conveyor is provided. The acceleration immediately after the start of lifting and lowering of the lifting conveyor and the deceleration just before a predetermined stop position are determined by the difference between the total weight of the lifting conveyor and the total weight of known balance weights attached to the lifting conveyor, respectively. The first parameter based on the specified unbalance load, which is defined by the sum of the total weight of the lifting conveyor and the total weight of the balance weights. A function to set the acceleration and the deceleration when the first parameter or the second parameter is smaller than when the first parameter or the second parameter is larger. In this manner, the control system further includes a moving distance to a target position of the hoisting conveyor, wherein the acceleration immediately after the start of the hoisting and lowering of the hoisting conveyor and a deceleration before a predetermined stop position can be known in advance. A lifting / lowering transport device having a function of setting the acceleration and deceleration when the moving distance is short compared to when the moving distance is long. 7. The lifting and lowering transport device according to claim 6, wherein
The total weight of the elevating conveyor is calculated using the weight of the conveyed object to be conveyed input and set by an operator and the weight of the elevating conveyor in an empty state registered in advance in the control system. Elevating transport device. 8. The lifting and lowering transport device according to claim 6, wherein
Means for detecting a load current of the servomotor in a stopped state during operation, wherein the control system determines a difference between a total weight of the lifting conveyor and a total weight of the balance weight based on the detected load current. That is, the weight of the conveyed object is calculated from the unbalanced load, and the total weight of the elevating conveyor is calculated by adding the weight of the elevating conveyor in an empty state registered in advance to the calculation result. Elevating transport device. 9. The lifting and lowering transfer device according to claim 6, wherein
The moving distance of the lifting conveyor is, in the control system,
An ascending / descending transport device, which is calculated from a tier at which a transported object is set and inputted by an operator and a current tier of the ascending / descending conveyor.