JP3701843B2 - Bag lifting device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention includes a carriage for raising and lowering a load that moves up and down with respect to at least a mast, a turret head that is mounted on the carriage so as to be capable of shifting in a horizontal direction, and a turret head that is mounted so as to be pivotable to the left and right. The present invention relates to a luggage lifting device including a fork.
[0002]
[Prior art]
Conventionally, a rack fork is configured as shown in FIGS. That is, as shown in FIGS. 7 and 8, the rack fork 1 is provided with a carriage elevating / lowering carriage 3 in a mast 2 that can be moved up and down, and a turret head 4 is mounted on the carriage 3 so as to be shiftable to the left and right. In addition, a fork 5 is mounted so as to be able to turn left and right with respect to the axis of the turret head 4.
[0003]
Then, when traveling to the designated rack position, the fork 5 is turned so that the fork 5 is opposed to the rack and the turret head 4 is shifted by a predetermined shift in order to load and unload the load 6 together with the pallet on the rack. It moves in the rack direction by the out amount and loads and unloads the luggage 6.
[0004]
At this time, in the case of an unmanned rack fork, the magnetic body embedded along the track of the floor surface is detected by a magnetic sensor provided on the vehicle body, and controlled so as to autonomously travel while detecting the traveling position, and a predetermined stop position When the vehicle arrives, the stop control is performed, and the loading / unloading control as described above is performed.
[0005]
By the way, in such a rack fork, as shown in FIG. 9A, when loading / unloading the luggage 6 on the designated shelf of the rack 8, as shown in FIG. In addition, since the mast 2 bends according to the height at the time of unloading, the unloading position of the luggage 6 varies depending on the deflection amount Δ, and a smooth unloading operation cannot be performed.
[0006]
In other words, when the deflection of the mast 2 is large, as shown in FIG. 9C, the luggage 6 is placed on the far side beyond the predetermined position of the rack of the rack 8, or the deflection amount of the mast 2 is small. In some cases, when the fork 5 is inserted into the pallet and the load 6 is taken out, there is a possibility that the amount of the fork 5 to be inserted becomes insufficient and the load 6 cannot be stably lifted together with the pallet.
[0007]
[Problems to be solved by the invention]
However, since the conventional rack fork 1 described above does not have a control function for adjusting the shift-out amount of the turret head 4 in consideration of such deflection of the mast 2, the rack fork 1 loads the luggage 6. There was a problem that wholesale could not be performed stably.
[0008]
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to detect the amount of mast deflection and adjust the shift-out amount of the turret head so that proper loading and unloading of the cargo can always be realized stably.
[0009]
[Means for Solving the Problems]
In order to achieve the above-described object, the present invention is directed to a load raising / lowering carriage that moves up and down with respect to a mast, a turret head mounted on the carriage so as to be horizontally shiftable, and an axis of the turret head. And a fork mounted so as to be able to turn left and right, a speed detection means for detecting the lifting speed of the luggage, and the weight of the luggage from the magnitude of the lifting speed of the luggage detected by the speed detection means. According to the load detection means to detect, the height detection means to detect the height of the load, the weight of the load detected by the load detection means, and the height of the load detected by the height detection means, Deflection amount deriving means for deriving the corresponding mast deflection amount, and the turret head shifter according to the deflection amount derived by the deflection amount deriving means. It is characterized in that it comprises a shift-out amount adjusting means for adjusting the door weight.
[0010]
According to such a configuration, the amount of deflection of the mast corresponding to the weight of the load detected by the load detection unit and the height of the load detected by the height detection unit is derived by the deflection amount deriving unit. Since the turret head shift-out amount is adjusted by the shift-out amount adjusting means in accordance with the amount of deflection of the mast, the load loading / unloading position shift as in the conventional case does not occur, and the proper load loading is always performed. Wholesale can be realized stably.
[0011]
The present invention further includes a storage unit that stores deflection amount data for each height of the load at each weight of the load previously derived by the deflection amount deriving unit, and the load is detected by the load detecting unit. And a deflection amount corresponding to the height of the load detected by the height detection means is read out from the storage unit and derived.
[0012]
According to such a configuration, it is possible to accurately derive the amount of deflection of the mast corresponding to the weight of the load detected by the load detection unit and the height of the load detected by the height detection unit.
[0013]
Further, the present invention is characterized in that the shift-out amount adjusting means adjusts the shift-out amount to be small when the deflection amount derived by the deflection amount deriving means is large.
[0014]
According to such a configuration, when the deflection of the mast is large, the shift-out amount is adjusted to be small. Therefore, as in the conventional case in which this adjustment is not performed, the load is placed far behind the predetermined position on the rack shelf. It wo n’t be left behind. On the other hand, if the amount of deflection of the mast is small, the shift-out amount is adjusted to be larger than when the mast is large. Therefore, when the fork is inserted and the load is taken out, the fork insertion amount does not become insufficient.
[0015]
Further, the present invention is characterized in that the speed detecting means calculates an ascending / descending speed by counting the number of pulses per predetermined time, and an encoder that generates a number of pulses corresponding to the ascending / descending distance of the carriage. .
[0016]
According to such a configuration, the lifting / lowering speed of the luggage can be detected, and the weight of the luggage can be accurately detected from the detected lifting speed.
[0017]
Further, the present invention is characterized in that the height detection means derives the height of the load from the lift distance of the carriage based on the number of pulses from the encoder of the speed detection means. According to such a configuration, the height of the load can be derived with high accuracy.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment in which the present invention is applied to an unmanned rack fork will be described with reference to FIGS. 1 is a block diagram of the control system, FIGS. 2 to 5 are operation explanatory diagrams, and FIG. 6 is a flowchart for explaining the operations.
[0019]
Note that the rack fork in this embodiment is basically the same as the configuration shown in FIGS. 7 and 8 except that there is no driver's seat for automatic operation. With reference to FIGS. 7 and 8, the configuration and operation of the control system will be mainly described.
[0020]
As shown in FIG. 1, the control system for the unmanned rack fork in this embodiment includes a travel drive device 11 that controls a travel motor and the like, a steering device 12 that steers drive steering wheels (not shown), and the elevation of the carriage 3. The drive device 13, the shift drive device 14 of the turret head 4, the turning drive device 15 of the fork 5, and the overall controller 16 are configured.
[0021]
The travel drive device 11 is a travel motor 111 for driving a drive steering wheel (not shown), a travel drive unit 112 that drives the travel motor 111, and a travel for deriving a travel distance from the rotational speed of the travel motor 111. An encoder 113 is provided.
[0022]
At this time, although not shown, the magnetic body embedded along the track on the floor surface is detected by a magnetic sensor provided on the vehicle body and autonomously travels while detecting the travel position, and reaches a predetermined stop position. The travel motor drive unit 112 is controlled by the controller 16 so that the stop control is sometimes performed.
[0023]
The raising / lowering driving device 13 corresponds to the raising / lowering motor 131 of the carriage 3, the raising / lowering driving unit 132 that drives the raising / lowering motor 131 based on the raising / lowering control signal from the controller 16, and the raising / lowering distance of the carriage 3 by the raising / lowering motor 131. And a lift encoder 133 that generates several pulses, and the controller 16 counts the number of pulses per predetermined time by the lift encoder 133 to calculate the lift speed.
[0024]
At this time, the lifting / lowering encoder 133 is composed of, for example, a rotary encoder, and one end of a wire or chain is fixed to the carriage 3, and the other end of the wire or chain whose middle is guided by a guide roller at the upper end of the mast 2 is lifted / lowered. The carriage 3 is wound up or drawn out by the rotation of the motor 131 to move the carriage 3 up and down, and the number of pulses corresponding to the lift distance of the carriage 3 by the rotation of the lift motor 131 at that time is generated.
[0025]
The shift drive device 14 includes a drive motor 141 for the turret head 4 and a shift drive unit 142 that drives the drive motor 141 based on a shift control signal from the controller 16. The shift drive device 14 and the controller 16 constitute a shift-out amount adjusting means.
[0026]
The turning drive device 15 includes a turning motor 151 for the fork 5 and a turning drive unit 152 that drives the turning motor 151 based on a turning control signal from the controller 16.
[0027]
The controller 16 includes a ROM storing a control program, a memory M including a data storage RAM, and a microcomputer including an arithmetic processing unit. Here, the memory M may be composed of an external storage device in addition to the built-in memory as shown in FIG.
[0028]
In the memory M, as a storage unit, data indicating the relationship between the weight W of the load 6 as shown in FIG. 2 and the lifting speed V of the load 6 under each load, as shown in FIG. Data indicating the relationship between the deflection amount Δ of the mast 2 for each height H of the load 6 at each weight W of the load 6 is stored in a table. At this time, the deflection amount Δ is, for example, a horizontal movement distance based on the deflection amount of the mast 2 when the load is zero, that is, when there is no load.
[0029]
That is, when lifting the load 6 placed on the fork 5, when a large load is applied to the fork 5, the speed at the time of rising is slow, and conversely the speed at the time of falling is fast. As shown in FIG. 2, the memory M of the controller 16 stores data indicating the relationship between the load W and the lifting speed V when the load 6 is lifted (same as shown in FIG. Solid lines in the figure) and data (broken lines in the figure) indicating the relationship between the load W when the load 6 is lowered and the lifting speed V are stored.
[0030]
Further, since the deflection amount Δ of the mast 2 is influenced not only by the height H of the load 6 but also by the weight W of the load, each weight is stored in the memory M of the controller 16 as shown in FIG. Data indicating the relationship between the height H of the baggage 6 and the deflection amount Δ according to W (W0, W1, W2,...) (Shown by a broken line, a solid line, a one-dot chain line in the figure) is stored.
[0031]
By the way, the controller 16 includes a counter that counts the number of pulses generated from the lift encoder 133 per predetermined time T, and calculates the lift speed V of the luggage 6 from the number of pulses per predetermined time T counted by the counter. . Further, the controller 16 reads the weight W of the luggage 6 corresponding to the magnitude of the lifting speed V calculated as described above from the memory M.
[0032]
For example, as shown in FIG. 4 (a), when the number of pulses generated at a predetermined time T is large, the ascending / descending speed is fast, and as shown in FIG. 4 (b), the number of pulses generated at the predetermined time T is small. Sometimes the lifting speed is slow. The speed calculation process by the controller 16 corresponds to speed detection means, and the weight W derivation process by the controller 16 corresponds to load detection means.
[0033]
Further, the controller 16 includes a counter that counts the total number of pulses generated from the lift encoder 133, and derives the height H of the load 6 from the lift distance of the carriage 3 based on the number of pulses counted by the counter. At this time, since the lifting / lowering distance of the carriage 3 per pulse from the lifting / lowering encoder 133 is associated in advance, if the total number of pulses is counted, the lifting / lowering distance of the carriage 3 can be known, and based on the lifting / lowering distance from the reference position, You can see the height. The height detection process by the controller 16 corresponds to a height detection means.
[0034]
Then, when loading / unloading the luggage 6 on the designated shelf of the rack 8, as shown in FIG. 5 (a), the mast according to the weight W of the luggage 6 and the height H of the luggage 6 at that time. 2, the weight W and the height H are respectively detected by the controller 16, and the deflection amount Δ corresponding to the detected weight W and the height H is read from the memory M, and the read deflection The shift-out amount of the turret head 4 is adjusted according to the amount Δ, and the cargo 6 is loaded and unloaded in an appropriate state as shown in FIG. Such a derivation process of the deflection amount Δ by the controller 16 corresponds to the deflection amount derivation means.
[0035]
At this time, when the deflection amount Δ derived by the controller 16 is large, the shift-out amount of the turret head 4 is adjusted to be small. Conversely, if the deflection amount Δ is small, the shift-out amount is adjusted to be larger than when the deflection amount Δ is large.
[0036]
Next, the operation will be described with reference to the flowchart of FIG. Now, when loading and unloading the luggage 6 on the designated shelf of the rack 8, as shown in FIG. 6, the elevating motor 131 is driven by the elevating drive unit 132 while traveling to a predetermined position (S1), and the carriage 3 is raised or lowered to the specified shelf height. In this way, while the carriage 3 is moved up and down, the weight of the package 6 being transported is detected by the controller 16 based on the pulse generated from the lift encoder 133.
[0037]
That is, the pulses generated from the lift encoder 133 are captured by the controller 16, and the number of pulses N per predetermined time T is counted by the counter (S2).
(1) V = k · N / T (where k is the up / down distance corresponding to one pulse)
The lifting / lowering speed V of the luggage 6 is calculated according to the equation (S3).
[0038]
Subsequently, the weight W of the load 6 is calculated based on the lifting speed V calculated by the controller 16 and the data of FIG. 2 stored in the memory M (S4, S5). That is, when the load 6 is lifted by the lifting / lowering motor 131, the value of the load W corresponding to the lifting / lowering speed V according to the above equation (1) is determined using the data indicated by the solid line in FIG. On the other hand, when the load 6 is lowered by the lifting / lowering motor 131, the value of the load W corresponding to the lifting / lowering speed V according to the above equation (1) is determined using the data indicated by the broken line in FIG.
[0039]
Further, the controller 16 calculates the lift distance (= k · N) of the carriage 3 from the pulse number N output from the lift encoder 133, and the load 6 can be placed on the designated shelf of the rack 8 together with the pallet. When the fork 5 is held at the height, the height H from the reference position of the load 6 is obtained (S6).
[0040]
Further, of the data shown in FIG. 3 stored in the memory M from the derived weight W and height H of the package 6 derived by the controller 16, the current height at the weight W of the corresponding package 6 is shown. The deflection amount Δ corresponding to H is read, the deflection amount Δ of the mast 2 is determined (S7, S8), and the controller 16 adjusts the shift-out amount of the turret head 4 according to the determined deflection amount Δ. (S9).
[0041]
In this way, when the deflection amount Δ of the mast 2 is large, the shift-out amount is adjusted to be small, so that it is possible to prevent the luggage 6 from being placed on the far side of the rack 8 beyond the predetermined position. On the other hand, if the amount of deflection of the mast is small, the shift-out amount is adjusted larger than when the mast is large. Therefore, when the fork 5 is inserted into the pallet and the baggage 6 is taken out, the amount of insertion of the fork 5 is insufficient. Can prevent the pallet from being lifted stably.
[0042]
Therefore, according to the above-described embodiment, the deflection amount Δ of the mast 2 corresponding to the load weight W and the load height H is derived, and the turret head 4 is shifted out according to the derived deflection amount Δ. Since the amount is adjusted, an appropriate loading / unloading of the luggage 6 can always be stably performed without causing a position shift of the loading / unloading of the luggage 6 as in the prior art.
[0043]
Further, in order to calculate the lifting speed V by counting the number of pulses per predetermined time generated from the lifting encoder 133 according to the lifting distance of the carriage 3, and to calculate the weight W of the luggage 6 from this lifting speed V, The weight of the load 6 can be detected with high accuracy.
[0044]
Furthermore, since the height H of the load 6 is obtained from the lift distance of the carriage 4 based on the total number of pulses generated from the lift encoder 133, the height of the load 6 can be derived with high accuracy.
[0045]
In the above-described embodiment, the case where the lifting speed V, the weight W of the load, and the height H are detected based on the pulse from the lifting encoder 133 has been described. Of course, the speed V, the weight W and the height H of the load may be detected.
[0046]
Further, in the above-described embodiment, the case where an unmanned rack fork is taken as an example has been described. However, the present invention can be similarly applied even when the unmanned rack fork is not used, and the same effect as the above-described embodiment can be applied. Can be obtained.
[0047]
In short, the present invention includes a carriage for raising and lowering a load that moves at least up and down with respect to the mast, a turret head that is mounted on the carriage so as to be capable of shifting in a horizontal direction, and a left and right turnable attachment to the axis of the turret head. The present invention is applicable as long as it is a luggage lifting / lowering device comprising a fork, and does not have to have a traveling function.
[0048]
The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit of the present invention.
[0049]
【The invention's effect】
As described above, according to the first aspect of the present invention, the weight of the load detected by the load detecting means and the amount of deflection of the mast corresponding to the height of the load detected by the height detecting means are bent. Since the shift-out amount of the turret head is adjusted by the shift-out amount adjusting unit according to the amount of deflection derived and derived by the amount deriving unit, there is no positional deviation of loading and unloading of the conventional baggage, It is possible to always stably load and unload luggage properly, and to provide a highly reliable luggage lifting device such as a rack fork.
[0050]
According to the second aspect of the present invention, the weight of the load detected by the load detecting means and the amount of mast deflection corresponding to the height of the load detected by the height detecting means are accurately derived. It becomes possible.
[0051]
According to the third aspect of the present invention, when the deflection of the mast is large, the shift-out amount is adjusted to be small. Therefore, as in the conventional case where this adjustment is not performed, the baggage is moved from a predetermined position on the rack shelf. There is no need to place it on the far side. On the other hand, if the amount of deflection of the mast is small, the shift-out amount is adjusted to be larger than when the mast is large. Therefore, when the fork is inserted and the load is taken out, the fork insertion amount does not become insufficient.
[0052]
According to the fourth aspect of the invention, the lifting speed of the load can be detected, and the weight of the load can be accurately detected from the detected lifting speed.
[0053]
Further, according to the invention described in claim 5, it is possible to accurately derive the height of the load.
[Brief description of the drawings]
FIG. 1 is a block diagram of a control system in an embodiment of the present invention.
FIG. 2 is an operation explanatory diagram of one embodiment of the present invention.
FIG. 3 is an operation explanatory diagram of one embodiment of the present invention.
FIG. 4 is an operation explanatory diagram of one embodiment of the present invention.
FIG. 5 is an operation explanatory diagram of one embodiment of the present invention.
FIG. 6 is a flowchart for explaining the operation of the embodiment of the present invention.
FIG. 7 is a side view showing an external configuration of a conventional example.
FIG. 8 is a plan view showing an external configuration of a conventional example.
FIG. 9 is an operation explanatory diagram of a conventional example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Rack fork 2 Mast structure 3 Carriage 4 Turret head 5 Fork 6 Luggage 13 Lift drive device 13
16 controller (speed detection means, load detection means, height detection means, deflection amount derivation means, shift-out amount adjustment means)
131 Elevating Motor 132 Elevating Drive 133 Elevating Encoder

Claims (5)

A load raising / lowering carriage that moves up and down with respect to the mast, a turret head mounted on the carriage to be horizontally shiftable, and a fork mounted on the turret head so as to be able to turn left and right In the lifting device,
Speed detecting means for detecting the lifting speed of the load;
Load detecting means for detecting the weight of the load from the magnitude of the lifting speed of the load detected by the speed detecting means;
A height detection means for detecting the height of the luggage;
Deflection amount deriving means for deriving the deflection amount of the mast corresponding to the weight of the load detected by the load detection means and the height of the load detected by the height detection means,
A load lifting apparatus, comprising: a shift-out amount adjusting unit that adjusts a shift-out amount of the turret head in accordance with a deflection amount derived by the deflection amount deriving unit. The deflection amount deriving means includes a storage unit that stores deflection amount data for each height of the load at each weight of the previously derived load, the weight of the load detected by the load detection unit, and 2. The bag lifting / lowering device according to claim 1, wherein a deflection amount corresponding to a bag height detected by a height detecting means is read out from the storage unit and derived. 3. The luggage lifting / lowering apparatus according to claim 1, wherein the shift-out amount adjusting means adjusts the shift-out amount to be small when the deflection amount derived by the deflection amount deriving means is large. 4. The speed detecting means according to claim 1, wherein the speed detecting means calculates an ascending / descending speed by counting the number of pulses per predetermined time with an encoder that generates a number of pulses according to the ascending / descending distance of the carriage. The luggage lifting device according to any one of the above. 5. The luggage lifting / lowering apparatus according to claim 4, wherein the height detecting means derives the height of the luggage from the lifting / lowering distance of the carriage based on the number of pulses from the encoder of the speed detecting means.

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