JP2631163B2 - Pallet transfer method and apparatus with variable cycle time - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pallet transfer method and apparatus having a variable cycle time for transferring pallets between assembly lines having the same cycle time or between assembly lines having different cycle times.

[0002]

2. Description of the Related Art In a conventionally known free-flow type automatic assembly line, necessary work time can be taken at each station, but when the pallet is stopped, collision of the pallet, vibration and noise are generated. The moving speed of the pallet is designed to be slow. In an assembly line having a cycle time,
The cycle time is set based on the longest stop time (Japanese Patent Laid-Open No. 28109/1989).

[0003]

As described above, in the free-flow automatic assembly line, there is a possibility that vibration and noise may be generated due to collision of the pallets, so that these problems are minimized. Another problem is that the moving speed of the pallet must be reduced. next,
In an assembly line with a fixed cycle time, the cycle time must be configured based on the longest stop time. Since there is no method of transferring the pallets, it was necessary to take out the pallets from the line and process them overtime.

[0004]

According to the present invention, a plurality of pallets having different cycle times are transferred from an assembly line having a predetermined cycle time to another assembly line having another cycle time. By successfully constructing the assembly line as a series of unified assembly lines, the aforementioned conventional problems were solved.

That is, the invention of the method is characterized in that a pallet is transferred from one assembly line having a predetermined cycle time to another assembly line having another cycle time in a straight-line synchronous transfer assembly line. This is a pallet transfer method with variable cycle time. In addition, 2 before and after transfer
The cycle time of one line is an integral multiple or a fraction of an integer
It is what it was.

[0006] Next, the invention of the apparatus is that a first assembly line and a second assembly line having the same cycle time are laid in parallel at a predetermined interval, and an end side of the first assembly line and a start side of the second assembly line. Wherein a third assembly line having a cycle time that is an integral multiple of the cycle time is laid between the pallet transfer device and the cycle time.

In another aspect of the present invention, a second assembly line having another cycle time is laid in parallel on a first assembly line having a cycle time, and an end side of the first assembly line and a start end side of the second assembly line. There is no stagnation during transfer between
A pallet transfer device having a variable cycle time, wherein an index conveyor is provided.

In the above, the pallet transfer conveyor may be an assembly line or not. The selection is determined in consideration of various conditions such as the length of the stop time, the type of work, and the installation of the work robot.

As described above, the present invention constitutes an entire series of assembly lines by transferring pallets between assembly lines having different stopping times. Conventionally, the time required by a generally used transfer method (for example, pick and place, robot, etc.) requires at least 3 seconds, but the transfer of a conveyor by a timing belt is about 0.3 seconds, which is sufficient for the purpose. Can be achieved.

[0010]

According to the present invention, one assembly line having a predetermined cycle time is connected to the other assembly line having another cycle time by an index conveyor. Assemble line. Also, the transfer speed is significantly improved.

Next, according to the apparatus of the present invention, the flow of pallets in each assembly line is unified, and a smooth operation is performed.

[0012]

Embodiment 1 The present invention will be described with reference to FIGS.

FIGS. 1 (a), (b), (c), (d), and (e) show a series of assembly lines having different cycle times interposed between two assembly lines having the same cycle time. It is composed. That is, between the first assembly line 1 having the same cycle time and the second assembly line 2, the third assembly line 3 having a cycle time three times that of the first assembly line 1 is provided.
, And from the first assembly line 1 to the third assembly line 3,
The pallet P can be transferred from the third assembly line 3 to the second assembly line 2.

In the above embodiment, the cycle time of the first assembly line 1 and the second assembly line 2 is, for example, 1 second (moving 0.2 second, stopping 0.8 second), and the cycle time of the third assembly line 3 Time is 3 seconds (moving 0.5 seconds, stopping 2.5
Second).

The third assembly line 3 has three index conveyors 4a, 4b, 4c arranged in parallel on a pallet feeding path 5. Therefore, a case where the state moves from the state of FIG. 1A to the state of FIG. 1E will be described.

1 (a) to 1 (e), pallets P1, P1
P2 and P3 advance in sequence as shown by arrows 6 to the stations corresponding to the third assembly line 3 as shown in FIGS. 1 (a) to 1 (d), and then as shown by arrows in FIG. 1 (e). It is transferred in the direction of 7. The pallet P of the first assembly line 1 in the above is
The pallet P of the second assembly line 2 advances in the direction of arrow 8 with the cycle time of 1 second, with the cycle time of 1 second. On the other hand, the pallet P on the third assembly line moves in the direction of arrow 7 once every three seconds.

FIG. 2 shows the relationship between the moving time of the pallet P and the stopping time. 2, the cycle time of the first assembly line is T _1, the movement time is T _1i, dwell time is T _1d. Therefore pallet P1, P2, because P3 is simultaneously transferred to the third assembly line 3 (FIG. 1 (e)), the cycle time T ₂ of the third assembly line is three times the T _1. Therefore, the travel time is T _2i and the stop time is T _2d . Second assembly line 2
The cycle time is T ₃ , the travel time is T _3i , and the stop time is T _3d . Therefore, in FIG. 2, T ₂ = nT ₁ = 3
The T _1. Further, T ₁ = T ₃ . Therefore, if T ₁ is 1 second, T ₃ is also 1 second and T ₂ is 3 seconds. However the movement time T _1i and T _3i is equal but, T _1i and T
_2i need not necessarily be the same. That is, the stop time T _2d
And the moving time T _2i should be equal to T ₂ .

The structure of the pallet P is shown in FIGS. A jig 9 is mounted on the surface of the pallet P, and a main component 10 is fitted on the jig 9. On the back surface, grooves 11 and 12 cross each other at right angles, and the projections 13 and 13 of the index conveyors 4a, 4b and 4c and the grooves 1
2, the index conveyor 4a moves in the direction of arrow 7 in FIGS.
4 and 15 are rotated in the directions indicated by the arrows 16), and the projection 13 is fitted into the groove 12, whereby the pallet P is reliably moved by a predetermined distance. In the figure, reference numerals 17 and 18 denote an assembly line 1,
2 is an index conveyor, and its projection 1
The relationship between 9 and 20 and the groove 11 of the pallet P is the same as in the case of the index conveyors 4a, 4b and 4c, and the description is omitted.

[0019]

Second Embodiment Another embodiment will be described with reference to FIGS.
7 (a), 7 (b), 7 (c), and 7 (d) are explanatory diagrams of pallet transfer, and FIG. 8 is an explanatory diagram of a time relationship accompanying pallet transfer. This embodiment is different from the first embodiment in that an assembly line is not used for transfer. In the figure, black circles indicate stations with pallets, and white circles indicate stations without pallets.

That is, the starting end of the second assembly line 22 is laid in parallel with a predetermined distance from the end of the first assembly line 21, and the starting end of the third assembly line 23 is located at the end of the second assembly line. Are laid in parallel.

The operation of the above embodiment will be described. Referring to FIG. 7A, three empty stations S1, S2 and S3 are located at the end of the first assembly line 21. Therefore, the cycle time of the first assembly line 21 is set to 1 second,
If the moving time is 0.3 seconds, the stop time is 0.7 seconds. Further, if the cycle time of the second assembly line 22 is 3 seconds (an integral multiple, for example, 3 times),
Since the transfer to the second assembly line must be performed immediately after the three pallets arrive at the first assembly line and while they are stopped, the transfer must be performed within 0.7 seconds. Since the required loading time is 0.7 seconds, in this case, the stop time is 2.3 seconds.

In the second assembly line, the stations S4, S
The pallets 5 and S6 are simultaneously transferred to the stations S7, S8 and S9. In this case, the transfer time must be long because the station has to be transported for a distance of three stations, but if it is 0.7 seconds, the stop time is 2.3 seconds. If both the transfer time to the second assembly line and the index time of the second assembly line are 0.5 seconds, the pallet dwell time on the second assembly line is 2.5 seconds.

Next, when three pallets are simultaneously transferred to the third assembly line 23 at the same time as the end of the index at the end of the second assembly line 22, each pallet has a moving time of 0.3 seconds and 0.7 seconds. , A smooth cycle can be repeated in the same manner as the cycle time of the first assembly line 21. Since the cycle time of the second assembly line is 3 seconds, the transfer from the second assembly line to the third assembly line (arrow 29) is performed within 0.7 seconds. The three pallets transferred to the third assembly line repeatedly move and stop at the same cycle time as the first assembly line at the same time as the completion of the transfer, and reach the final station.

In the above embodiment, as shown in FIGS. 7 (a), (b), (c) and (d), empty stations S1, S2 and S3 at the end of the first assembly line 21 are provided with arrows according to the cycle time. When the pallets are sequentially transported as shown in FIGS. 24, 25 and 26, and all the pallets have been moved, the empty conveyor S4 of the second assembly line 22, as shown by arrow 27 (7 (d)), is transferred by the transfer conveyor. To S5, S6, the stations S1, S2,
The pallet of S3 is transferred. The second assembly line 22
Is three times as long as the cycle time of the first assembly line (for example, 3 seconds).
The three pallets S5 and S6 are grouped into groups g1, g2 and g
As shown in FIG. Next, at the end of the second assembly line 22, the third assembly line 2
The pallets facing the empty stations S10, S11 and S12 are transferred as indicated by an arrow 29 (FIG. 1 (d)) and moved to one pallet by the cycle time of the third assembly line 23. .

[0025]

According to the present invention, a pallet is transferred from one assembly line having a predetermined cycle time to another assembly line having another cycle time by using an index conveyor in a straight-type index assembly line. and, moreover there is an effect because there is no stagnation during transfer to facilitate the transfer between assembly line, and automated can Rutotomoni, the assembly line can be made faster.

[Brief description of the drawings]

FIG. 1 is a plan view showing a flow of a pallet according to an embodiment of the present invention, wherein FIG. 1 (a) is a view before entering a transfer station, and FIG.
Figure showing two pallets reaching the transfer station, (c) shows 2
Figure showing two pallets reaching the transfer station.
Figure showing two pallets reaching the transfer station.

FIG. 2 is a diagram showing a time relationship between the movement of the pallet shown in FIG.

FIG. 3 is a partially enlarged plan view of FIG. 1;

FIG. 4 is an enlarged front view of the same sectional view of FIG. 3;

FIG. 5 is an enlarged sectional view of the same pallet.

FIG. 6 is an enlarged back view of the same pallet.

FIG. 7 is a conceptual diagram showing pallet arrangement and transfer according to another embodiment.

8 is a diagram showing a time relationship of the embodiment of FIG. 7;

[Description of Signs] 1 First assembly line 2 Second assembly line 3 Third assembly line 4a, 4b, 4c, 4d Index conveyor 5 Feeding path 9 Jig 10 Main parts 14, 15 Timing pulley 17, 18 Index conveyor

Claims (3)

(57) [Claims] 1. A linear synchronous transfer assembly line, per from one assembly line with a predetermined cycle time, to transfer using the index conveyor pallet to another assembly line with different cycle time transfer Before and after
Two cycle times are integral multiples in the pallet flow direction
Alternatively, a pallet transfer method with a variable cycle time, characterized in that the pallet is set to a fraction of an integer . 2. A first assembly line having the same cycle time.
And the second assembly line are laid in parallel at predetermined intervals.
The end of the first assembly line and the beginning of the second assembly line
Cycle time that is an integral multiple of the cycle time
That the specified number of third assembly lines with im
Pallet transfer device with variable cycle time. 3. A first assembly line having a cycle time.
And a second assembly line with a different cycle time
And the end of the first assembly line and the start of the second assembly line.
In between the end side, there is no stagnation during transfer.
Cycle characterized by interposition of a dex conveyor
Pallet transfer device with variable time.