JP3086184B2 - How to calculate the parts delivery 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 method of calculating a part delivery time in a preceding process based on a production plan of a subsequent process.

[0002]

2. Description of the Related Art Conventionally, in an assembly line in which the order of model lots to be carried in a day, the number of production lots, the tact time and the number of works in process are set as shown in FIG. In order to obtain the time Jc at which the leading work of the lot C having the third rank is carried into the assembly line, the following calculation method is adopted.

Jc = start time + tact time of lot A × (production number of lot A−number of work in process) + tact time of lot B × production number of lot B + rest time. Here, from the production plan of the day, the tact time of the lot A is 24.0 seconds, and the production number of the lot A is 300
The lot T has a takt time of 27.0 seconds, and the production number of the lot B is 100. This assembly line is composed of 140 processes, and the number of in-process units is 14
0 units.

[0005] As shown in FIG.
In a state where the top workpiece A ₁ had been carried into the final step of the assembly line on the day of the lot A, the first step in the assembly line, the 140th workpiece A ₁₄₀ is carried from the head of the lot A (Line-on) It is in the state that was done. Therefore, when 24.0 seconds which is the cycle time of lot A from the opening time has elapsed, so that the top workpiece A ₁ on the day of the lot A is unloaded from the assembly line (line off). Then, the finishing time is in _{state 1} 'head work A' of lot A of the next day had been carried into the final step of the assembly line, the first step in the assembly line, from the head of the lot A '140 The second work A ′ ₁₄₀ is in a loaded state.

The tact time of the assembly line is set to the maximum tact time among the tact times of the respective models on the assembly line. Therefore, as shown in FIG. 6, when lot B, lot C, and lot D exist on the assembly line, the 21st work D from the top of lot D
Distance between the workpiece D _{20 to 21} are carried into the assembly line, the 27 seconds which is the cycle time of the lot B.

[0006]

However, in the conventional method of calculating the part carry-in time, the tact time used in the calculation formula is the largest tact time among the tact times of the respective models on the assembly line. Since it was used without considering the setting of the time, there was a problem that a considerable difference occurred between the plan and the actual time when the leading work of each lot was carried into the assembly line. . Further, there is a problem that the time at which the last work of the day is carried into the assembly line is significantly different from the closing time.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is to provide a component delivery time at which the delivery time of a component to an assembly line can be more accurately obtained. Is to be provided.

[0008]

In order to solve the above problems SUMMARY OF THE INVENTION The present invention provides a method of calculating the component carrying time from the component processing line to a different assembly line tact time the model, from the host computer of the assembly line production plan
An assembly line production plan reception processing unit for receiving
Line delivery time calculation to calculate the parts delivery time to the line
From the start of work to the end of work using an arithmetic processing unit equipped with a processing unit
The work on the assembly line is developed , and the maximum tact time among the tact times of the respective models existing on the assembly line is defined as the tact time of the assembly line. To calculate a correction value by dividing the daily operating time by the flow time, and multiply this correction value by the tact time of each model to obtain a correction tact time. The tact time is added and added to the start time to calculate the time at which a specific part is carried into the assembly line.

[0009]

Embodiments of the present invention will be described below with reference to the accompanying drawings. Here, FIG. 1 is a system configuration diagram for implementing a method for calculating a component carry-in time according to the present invention, FIG. 2 is a flowchart showing the same calculation process, and FIG. 3 is an explanatory diagram showing a work in progress of an assembly line at the start and end of work. It is.

As shown in FIG. 1, a system for implementing a method for calculating a component delivery time according to the present invention includes a factory host computer 1 which creates a production plan for an entire factory and instructs an assembly line to execute the production plan. A processing unit 2 for calculating a time at which a work is carried into an assembly line based on a production instruction from a factory host computer 1, and a processing unit 2
3 and printer 4 for outputting the calculation result of
And a keyboard 5 for inputting predetermined data and the like to the arithmetic processing unit 2.

The processing unit 2 includes an assembly line production plan reception processing unit 6 for receiving an assembly line production plan from the factory host computer 1, and an assembly line production plan received by the assembly line production plan reception processing unit 6. Assembly line production plan file 7 storing assembly line, assembly line operation time file 8 managing assembly line operation time, and assembly line production plan stored in assembly line production plan file 7 and operation managed by assembly line operation time file 8 It is composed of a line carry-in time calculation processing unit 9 for calculating a work carry-in time to the assembly line from time and the like, and an assembly line carry-in time file 10 for storing processing results of the line carry-in time calculation processing unit 9. The assembly line production plan file 7 contains information such as a work unloading plan from the assembly line, the number of work in progress on the assembly line, and the tact time for each model of the assembly line.

Next, a method for calculating a component delivery time according to the present invention will be described with reference to a flowchart shown in FIG. First, in step S1, the work unloading plan from the assembly line and the number of in-process information on the assembly line and the assembly line operating time file 8 stored in the assembly line production plan file 7 are used to change the assembly line from the start to the end of the operation. Deploy a work.

[0013] progress status of the assembly line at the time of opening and during closing, as shown in FIG. 3, is conveyed to the work to be carried out of the assembly line after a predetermined tact time after opening W _1, to the assembly line finishing just before the work and W _m. Therefore, the number of works to be deployed on the assembly line from the start to the end is m. Here, as in FIG. 4, assuming that the number of in-process units k is 140 units and the number of production units P per day is 1070 units, the work W _m is the 1210th work from the work W ₁ (the number of production units per day P = 1070 units and the number of units in progress) k = 140 units). That is, the relationship between m, k and P is P = m−k
It is.

Next, in step S2, the work W
Assuming that the basic tact times of the workpieces ₁ to W _m are T _{1 to} T _m , respectively, the n-th time is carried into the assembly line (line-on) based on the model-specific tact time stored in the assembly line production plan file 7. ) is the tact time T _'n (line on intervals theoretical work W _n of time), the maximum tact of the workpiece _{W n- (k-1) ~W} n tact time in the assembly line It will be time. Tact time T _'n theoretical is obtained by the following equation.

T ′ _n = MAX (T _{n− (k−1) to} T _n )

[0016] In step S3, the operating time in: tact time T _'n theoretical work W _n at the time of being carried into the (production volume P 1070 cars) to the assembly line and total flow time of day S Ask for. Flow time of the day S is obtained by the following expression for total tact time T _'n theoretical only one day of production volume P (P = m-k) .

[0017]

(Equation 1)

Next, in step S4, based on the flow time S and the operation time H of the assembly line operation time file 8,
So that the workpiece W _m when closing is carried always the first step of the assembly line, to obtain a correction value α for correcting the tact time of the theoretical. The correction value α is obtained by the following equation that divides the operating time H by the flowing time S.

Α = H / S

In step S5, each of the workpieces W _{1 to} W _m
Of the correction tact time t _{1 to} t _m is obtained. Correction tact time t _n of the workpiece W _n is obtained by the following equation is multiplied by the correction value α to the tact time T _'n theoretical.

T _n = T ' _n × α = T' _n × H / S

[0022] Then, in step S6, in consideration of the operating time based on the correction cycle time t ₁ ~t _m for each work W ₁ to _W-m, loading time at the assembly line of the workpiece W ₁ to _W-m Find J _{1 to} J _m . Loading time J _n to assembly line of the workpiece W _n is obtained by the following equation opening time as a reference.

[0023]

(Equation 2)

Further, in step S7, each work W
The delivery time of the leading work of each lot to the assembly line among the delivery times J _{1 to} J _m to the assembly line of _{1 to} W _m is defined as the delivery time to the assembly line of each lot. This completes the process of calculating the work transfer time to the assembly line.

[0025] When the widget state of assembly line during opening and closing shown in the production plan and 5 shown in FIG. 4, the carry-time J _B of example to the assembly line of the lot B, Lot A
Since the number of products manufactured is 300 or the like, it can be obtained by the following equation.

[0026]

(Equation 3)

Further, the carrying-time J _C to assembly line of the lot C, 300 units production volume of the lot A is, since the number of production lots B is like 100 units, is obtained by the following expression.

[0028]

(Equation 4)

[0029] In addition, carry-time J _I to the assembly line of the lot I can be obtained by the following equation.

[0030]

(Equation 5)

[0031]

As described above, according to the present invention, it is possible to more accurately calculate the time at which parts are transferred to an assembly line, which is a post-process, and thus to improve the accuracy of a part machining plan in the preceding process. be able to.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram that implements a method of calculating a component delivery time according to the present invention.

FIG. 2 is a flowchart showing a calculation process of a method for calculating a component delivery time according to the present invention;

FIG. 3 is an explanatory diagram showing a work in progress of an assembly line at the start and end of work.

FIG. 4 is a table showing a production plan of the day and a production plan of the next day.

FIG. 5 is an explanatory diagram showing a work-in-progress state of an assembly line at the start and end of work when explaining a conventional method for calculating a component delivery time.

FIG. 6 is an explanatory diagram showing a work in progress of an assembly line.

[Description of References] 1 ... Factory host computer, 2 ... Operation processing device, 3 ...
Display 4, printer 5, keyboard 5, assembly line production plan reception processing unit 7, assembly line production plan file 8, assembly line operating time file 9, line loading time calculation processing unit 10, assembly line loading Time file.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-6-44208 (JP, A) JP-A-7-28896 (JP, A) JP-A-3-8655 (JP, A) JP-A-2- 311223 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B23P 21/00 307 B23Q 41/08 B62D 65/00

Claims (1)

(57) [Claims] 1. A depending on the model from the component processing line in the method of calculating the component carrying time to a different assembly line tact time, produced from the host computer of the assembly line
An assembly line production plan reception processing unit for receiving a plan;
Line loading time for calculating the component loading time to the assembly line
Use an arithmetic processing unit equipped with a calculation processing unit to
The work on the assembly line at the time of operation is developed , and the maximum tact time among the tact times of the respective models present on the assembly line is defined as the tact time of the assembly line. , The flow time of the day is calculated by calculating the correction time by dividing the operation time of the day by the flow time, and the correction value is multiplied by the tact time of each model to obtain a correction tact time. A method for calculating a component delivery time, wherein the correction tact time is integrated and added to a start time to calculate a delivery time of a specific component to the assembly line.