JP2010068588A - Travel control system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the excess heat generation of a linear motor, in a travel control system for controlling the travel of a carrying means such as a vehicle or the like driven with, for example, the linear motor. <P>SOLUTION: The travel control system (100) is driven with the linear motor and also controls the travel of the carrying means (3) capable of carrying an object to be carried. The travel control system includes: an energizing means (4) capable of switching the energization of the linear motor to travel the carrying means at an acceleration speed, a deceleration speed or at a constant speed; a heat generation amount specifying means (5) for specifying the heat generation amount related to the linear motor from prior to a predetermined time up to the present; and an acceleration control means (7) for controlling the energizing means to switch the energization to the side of suppressing the accelerated traveling when the specified heat generation amount exceeds a predetermined heat generation amount threshold value. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a technical field of a traveling control system that controls traveling of a conveying unit such as a vehicle driven by a linear motor.

  With regard to this type of travel control system, for example, there is a method for accurately detecting a phenomenon in which the coil temperature approaches the temperature rise limit of the coil by detecting an overload of the motor based on a control signal output by a servo control device, for example. Yes (see Patent Document 1).

  Further, for example, there is a device that obtains a temperature rise value of a motor based on an operation state and a heat generation amount of a linear motor, and executes an overload process when the obtained temperature rise value exceeds an allowable temperature rise value (see Patent Document 2). ). According to this apparatus, as overload processing, overload protection for protecting the motor is executed based on the mode temperature.

JP-A-5-316781 JP 2006-333686 A

  However, according to the method of Patent Document 1 and the apparatus of Patent Document 2 described above, a temperature rise or overload of a motor (including a coil) is detected, while a process that resists the temperature rise or overload is specific. Is not disclosed.

  According to the knowledge of the inventor of the present application, for example, a linear motor may generate excessive heat in a running pattern of energization. In this case, there is a technical problem that the temperature of the linear motor is output as an error on the system, and the drive by the linear motor may be urgently stopped.

  The present invention has been made in view of the above-described problems, for example, and an object thereof is to provide a travel control system capable of suppressing excessive heat generation of a linear motor.

  In order to solve the above-described problems, the travel control system of the present invention is a travel control system that controls the travel of a transport unit that is driven by a linear motor and that can transport an object to be transported. The transport unit is accelerated and decelerated. Alternatively, in order to run at a constant speed, energizing means capable of switching energization to the linear motor, heat generation amount specifying means for specifying a heat generation amount from a predetermined time before the present time to the linear motor, and the specified heat generation And an acceleration suppression unit that controls the energization unit to switch the energization to a side that suppresses the traveling during acceleration when the amount exceeds a predetermined heat generation amount threshold value.

  According to the travel control system of the present invention, the travel control system is a transport system that transports an object to be transported such as FOUP (Front Opening Unified Pod) by a transport means such as OHT (Overhead Hoist Transport) or a vehicle. Applied. The conveying means of the present invention is driven by a linear motor and travels along a track such as a rail laid on a ceiling or a floor, for example, in a factory for manufacturing a semiconductor device. Regarding the control related to the travel of the transport means, the power supply to the linear motor is switched by the power supply means, for example, according to the basic travel pattern. Then, the conveying means travels at an acceleration, deceleration or constant speed.

  In the present invention, during the running, the heat generation amount from the predetermined time to the present is specified by the heat generation amount specifying means. Here, the “predetermined time” is, for example, several tens of seconds (s), and the “heat generation amount” may be, for example, an average heat generation amount that is an average value of the heat generation amounts generated within the predetermined time, or the heat generation thereof. It may be a cumulative calorific value that is a cumulative value of the quantity. In addition, if it is an average calorific value, the calorific value threshold (namely, average calorific value threshold) corresponding to the average calorific value is set, and if it is a cumulative calorific value, the calorific value threshold corresponding to the cumulative calorific value (that is, cumulative calorific value). Threshold) is set. Then, it is determined by the acceleration suppression means whether or not the specified heat generation amount exceeds a predetermined heat generation amount threshold value. Here, the “predetermined heat generation amount threshold value” is a threshold value that serves as a reference for determining whether to switch energization. The “predetermined heat generation threshold value” is the relationship between the heat generation amount and the performance of the linear motor temperature rise and the heat resistance of the linear motor, which is determined experimentally, empirically, or by simulation. In this case, the temperature is set in advance as a value of the amount of heat to be stopped without delay. At this time, the “predetermined heat generation amount threshold value” may be a fixed value unique to each linear motor or the travel control system, and for example, the usage environment such as the ambient temperature, room temperature, current speed, and cooling status may be set as a parameter. The value may be variable. The “predetermined heat generation amount threshold value” is, for example, several tens of watts (W), and may be a heat release amount when the linear motor is stopped.

  In the determination using the heat generation amount threshold value, when the heat generation amount exceeds a predetermined heat generation amount threshold value, the energization unit is controlled by the acceleration suppression unit, and the energization is switched to the side that suppresses the travel by acceleration. . Here, “running with acceleration” may cause the linear motor to generate excessive heat depending on, for example, the time of running with acceleration and the magnitude of acceleration. “Switching energization to the side to suppress” such “running at acceleration” means, for example, in a narrow sense, switching from energization to stop running at acceleration and run at constant speed or deceleration. Means. In a broad sense, it also includes switching energization so as to reduce acceleration without stopping running at acceleration. In the present invention, the amount of heat generated in the linear motor is suppressed by such control. Note that “when the predetermined heat generation amount threshold value is exceeded” may be “when the heat generation amount is greater than or equal to the predetermined heat generation amount” or “when larger than the predetermined heat generation amount”.

  As described above, when the calorific value per predetermined time exceeds the predetermined calorific value threshold, it is possible to suppress excessive heat generation of the linear motor by switching the energization to the side that suppresses running during acceleration. It becomes.

  In one aspect of the travel control system of the present invention, the acceleration suppression means moves the transport means to the constant when the specified heat generation amount exceeds the predetermined heat generation amount threshold during traveling at the acceleration. The energization means is controlled so as to switch the energization so as to run at a speed or the deceleration.

  In this aspect, when the specified heat generation amount exceeds a predetermined heat generation amount threshold during traveling at acceleration, the energization unit is controlled by the acceleration suppression unit, and the transport unit travels at a constant speed or at a low speed. Then, compared with the case where it travels by acceleration, the amount of heat generated in the linear motor is reduced, and excessive heat generation of the linear motor can be suppressed.

  In another aspect of the travel control system of the present invention, the energization unit can switch the energization so that the conveyance unit is driven by the acceleration by any one of a plurality of types of acceleration as the conveyance unit. And the acceleration suppression means moves the conveying means to the current acceleration among the plurality of types of accelerations when the specified heat generation amount exceeds the predetermined heat generation amount threshold during traveling at the acceleration. The energization means is controlled to switch the energization so that the vehicle travels at an acceleration with a lower acceleration.

  According to this aspect, when the specified heat generation amount exceeds a predetermined heat generation amount threshold during traveling at acceleration, the energization unit is controlled by the acceleration suppression unit, and the conveyance unit is selected from a plurality of types of acceleration. Drive with acceleration that is lower than the current acceleration. Here, the “plural types of accelerations” may be, for example, several types of accelerations set to reach the maximum speed in several stages. When traveling at “acceleration lower than the current acceleration” among these “plural types of acceleration”, the amount of heat generated in the linear motor is reduced compared to when traveling at the current acceleration, and the linear motor is excessive. It is possible to suppress excessive heat generation.

  In another aspect of the travel control system of the present invention, the energization means can switch the energization so that the conveyance means is driven as the acceleration, and the conveyance means is caused to travel by acceleration by any one of a plurality of accelerations. Yes, the energization can be switched so that the conveying means travels at a deceleration by a single deceleration with the conveying means as the deceleration.

  According to this aspect, the energizing means causes the conveying means to travel according to a basic travel pattern, for example. Specifically, the transport unit first travels with acceleration by any one of a plurality of accelerations. Here, the “plurality of accelerations” may be several types of accelerations set to reach the maximum speed in several stages, for example. Subsequently, when the current speed of the transport unit reaches, for example, the maximum speed, the transport unit travels at a deceleration by a single deceleration. Here, the “single deceleration” may be a deceleration set in advance in consideration of the heat dissipation performance of the linear motor, for example. In either case, the deceleration is performed simply and quickly, which leads to the reduction of heat generation in the linear motor without delay. Subsequently, when the current speed of the transport unit reaches, for example, a predetermined minimum speed, the transport unit travels at a constant speed for a predetermined time. As a result, the basic traveling pattern goes around.

  In another aspect of the travel control system of the present invention, the acceleration suppression means switches the energization to the side that extends the time for traveling at the constant speed or the energization when the predetermined heat generation amount threshold is exceeded. The energization means is controlled to maintain.

  According to this aspect, when the specified heat generation amount exceeds a predetermined heat generation amount threshold during traveling at acceleration, the energization unit is controlled by the acceleration suppression unit, and the time for traveling at a constant speed is extended. On the side, energization is switched or energized. Here, “the side of extending the time for running at a constant speed” means, for example, stopping running at acceleration and running at a constant speed. Alternatively, for example, even when it is time to run at an acceleration according to a basic running pattern, it may mean running at a constant speed without stopping running at a constant speed. Specifically, for example, a constant speed section that travels at a constant speed is set between the end point of the deceleration section that travels by deceleration and the start point of the acceleration section that travels by acceleration. In this case, the time for traveling in the constant speed section may be extended to, for example, several times the time set in the basic travel pattern. As a result, the constant speed section can be extended and the acceleration section can be retracted to suppress the amount of heat generated in the linear motor.

  In this aspect, the acceleration suppression means switches the energization to the side to run at the deceleration when the state exceeding the predetermined heat generation amount threshold value is still continued even if the predetermined time threshold value is exceeded. The energization means may be controlled.

  According to this configuration, when the state in which the specified heat generation amount exceeds the predetermined heat generation amount threshold value still exceeds the predetermined time threshold value during the acceleration traveling, the acceleration suppression unit The energization means is controlled, and the energization is switched to the side to run at a reduced speed. Here, the “side driven by deceleration” means, for example, stopping running by acceleration and running by deceleration. Alternatively, for example, even when it is time to travel by acceleration according to the basic travel pattern, it may mean that the vehicle travels by deceleration without stopping the travel by deceleration. Specifically, for example, at least a part of the section set as the acceleration section in the basic traveling pattern is switched to the deceleration section. This makes it possible to suppress the amount of heat generated in the linear motor by partially disabling traveling during acceleration.

  In another aspect of the travel control system of the present invention, the current speed of the transport means, the current acceleration or deceleration of the transport means traveling at the current speed, and the transport means traveling at the current speed are transported. The calorific value is specified based on the presence or absence of the transported object.

  In this aspect, during travel at acceleration, the heat generation amount is specified by the heat generation amount specifying means based on the current speed, acceleration or deceleration, and the presence or absence of the object to be conveyed. Specifically, for example, the calorific value is a value obtained by multiplying the calorific value associated with traveling at acceleration or deceleration by the calorific value obtained by subtracting the calorific value due to air resistance during traveling by the period for controlling the energizing means. It may be a value divided by a unit time for specifying the quantity (that is, the “predetermined time” in the present invention). Here, the “heat dissipation amount” is specified based on, for example, the current speed, and the “heat generation amount” is specified based on, for example, acceleration and the presence / absence of a conveyed object. This makes it possible to accurately specify the “heat generation amount” used for determining excessive heat generation of the linear motor.

  For example, the use environment such as the ambient temperature, the room temperature, and the cooling condition may be used as a parameter for specifying the heat generation amount. In other words, the amount of heat generated may be specified only in terms of the amount of heat that actually generates heat, and may be specified in a pure sense, or may be generated in consideration of the amount of heat radiated from the linear motor. A value obtained by subtracting the amount of heat radiated from the amount of heat may be treated as a kind of heat generation in a broad sense. On the other hand, use environments such as ambient temperature, room temperature, and cooling conditions may be taken into account when setting the heat generation amount threshold value.

  In another aspect of the traveling control system of the present invention, the heat generation amount specifying means specifies an average value of the heat generation amount from the predetermined time before to the present time as the heat generation amount.

  In this aspect, the heat generation amount threshold value is a value (that is, average heat generation amount threshold value) corresponding to the average value of heat generation amount (that is, average heat generation amount). On the other hand, the calorific value specifying means may identify the cumulative value of the calorific value from a predetermined time to the present as the calorific value. In this case, the calorific value threshold is the cumulative value of the calorific value (that is, the cumulative calorific value). ) (That is, a cumulative calorific value threshold). Therefore, by using the average calorific value as a determination criterion when performing the determination as described above, overheating of the linear motor can be prevented reliably and accurately.

  The operation and other advantages of the present invention will become apparent from the best mode for carrying out the invention described below.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 functionally shows the configuration of the travel control system according to the embodiment. FIG. 2 shows a speed graph showing the basic running pattern of the energizing means of FIG. 1 on the upper side, and shows a calorific value graph showing the calorific value and the speed proportional heat quantity corresponding to the running pattern on the lower side.

  In FIG. 1, the travel control system 100 includes a rail 1, a vehicle 3, and a conveyance instruction unit 10. The rail 1 serves as a track for the vehicle 3 to travel in the direction D1. Permanent magnets (not shown) are arranged on both sides of the rail 1.

  The vehicle 3 includes a linear motor (not shown) as an example of the “conveying means” according to the present invention, and travels by electromagnetic propulsion between the linear motor and the permanent magnet on the rail 1 side. The linear motor is supplied with electric power from the energization unit 11 described later. The vehicle 3 transports and transfers FOUP (an example of the “conveyed object” according to the present invention) to a stocker (or stacker) (not shown) installed along the rail 1 and a manufacturing apparatus as the vehicle travels. To do. In the present embodiment, the vehicle 3 includes an energization unit 4, a heat generation amount specifying unit 5, and a control unit 6.

  As an example of the “energizing unit” according to the present invention, the energization unit 4 switches the power supplied to the linear motor according to the basic travel pattern in a normal time that is not a first suppression mode or a second suppression mode described later.

As shown in the upper graph of FIG. 2, in the basic traveling pattern, the vehicle 3 is gradually moved from a state where the vehicle 3 is stopped (that is, speed “0” (m / s)) or is traveling at a constant speed, that is, , acceleration "An1" (m ^{/ s} 2), "An2" (m ^{/ s} 2), accelerated to rise gradually in the order of "An3" (m / ^{s 2).} The vehicle 3 that has reached the maximum speed (that is, “Vmax” (m / s)) is decelerated at a deceleration “An4” (m / s ² ), and then stops or travels at a constant speed. Thus, a series of running patterns is completed. In the present embodiment, the energization unit 4 sets a section in which the vehicle 3 travels at a constant speed (hereinafter referred to as “constant speed section”) between such basic travel patterns. The energization unit 4 supplies electric power to the linear motor so as to travel in a constant speed section for 1 second at normal times.

As shown in the lower graph of FIG. 2, the linear motor generates heat corresponding to the basic travel pattern. Specifically, during acceleration in the acceleration "An1" (m / ^{s 2),} the heating value "Win1" (W) is generated, during acceleration in the acceleration "An2" (m / ^{s 2),} heating A quantity “Win2” (W) is generated, and a heat generation amount “Win3” (W) is generated during acceleration with an acceleration “An3” (m / s ² ). Thereafter, the linear motor generates a heat generation amount “Win4” (W) during deceleration at the deceleration “An4” (m / s ² ) due to the regenerative resistance. When the absolute values of the accelerations or decelerations “An1” to “An4” (m / s ² ) and the heat generation amounts “Win1” to “Win4” (W) satisfy the relationship of the expression (11), 12). In other words, the greater the acceleration or deceleration gradient, the greater the amount of heat generation, and the smaller the inclination, the smaller the amount of heat generation.

| An4 |> | An1 |> | An2 |> | An3 | (11)
Win4>Win1>Win2> Win3 (12)

The linear motor generates heat corresponding to the basic traveling pattern, and radiates heat by air resistance received during traveling. Specifically, while accelerating in the order of acceleration “An1” (m / s ² ), “An2” (m / s ² ), “An3” (m / s ² ), the amount of heat release gradually increases and decreases. While decelerating at the speed “An4” (m / s ² ), the heat release amount gradually decreases. That is, the heat radiation amount increases or decreases in proportion to the traveling speed. In the present embodiment, such a heat release amount is referred to as a speed proportional heat release amount. Note that the heat generation amount and the speed proportional heat dissipation amount are specified by the following expressions (1) and (2).

  As an example of the “heat generation amount specifying unit” according to the present invention, the heat generation amount specifying unit 5 uses the average value of the heat generated from the linear motor as the average heat generation amount Wavg (that is, an example of the “heat generation amount” according to the present invention). As specified. In the present embodiment, the heat generation amount specifying unit 5 detects the current speed V1 based on an encoder value indicated by an encoder (not shown) attached to the linear motor at the time of specifying, and the power supplied by the energizing unit 4 Based on the current acceleration or deceleration Anx (hereinafter simply referred to as “acceleration / deceleration Anx”). Furthermore, it is detected whether or not the body of the vehicle 3 is loaded with FOUP.

  Next, a method for specifying the average calorific value Wavg will be described in detail. The heat generation amount specifying unit 4 specifies the heat generation amount Win and the speed proportional heat release amount Wout prior to specifying the average heat generation amount Wavg.

The calorific value Win (W) is the current acceleration / deceleration speed Anx (m / s ² ), the current conversion constant β 0 (A / (m / s ² )) based on the presence or absence of FOUP loaded on the vehicle 3, and the linear motor Based on the winding resistance value r0 (Ω), it is specified by equation (1).

Win = (β0 * Anx) ² * r0 (1)

  The speed proportional heat dissipation amount Wout (W) is specified by Equation (2) based on the current speed V1 (m / s) and the conversion constant α0 (W / (m / s)) based on the linear motor temperature at the time of stoppage. Is done.

      Wout = α0 * V1 (2)

  The average heat generation amount Wavg (W) is calculated based on the equation (3) based on the specified heat generation amount Win (W), the speed proportional heat dissipation amount Wout (W), the control cycle Y0 (s), and the specific unit time X0 (s). ). The control cycle Y0 is a unit time during which an acceleration suppression process, which will be described later, is executed while the transfer instruction unit 10 instructs transfer related to semiconductor element manufacturing. The specific unit time X0 indicates a reference time during which the average calorific value Wavg is specified, and is 30 seconds in this embodiment.

  Wavg = Σx {(Win−Wout) * Y0} / X0 (3)

  The heat generation amount specifying unit 5 transmits a signal indicating the specified average heat generation amount Wavg to the acceleration suppression unit 7 described later.

  The control unit 6 includes a processor, a memory, and the like, and controls each unit of the vehicle 3 based on an instruction from the conveyance instruction unit 10. The control unit 6 includes an acceleration suppression unit 7.

  The acceleration suppression unit 7 performs a pressure suppression process for controlling the energization unit 4 according to the average heat generation amount Wavg from the heat generation amount specifying unit 5 as an example of the “acceleration suppression unit” according to the present invention. Specifically, the acceleration suppression unit 7 compares the average heat generation amount Wvg with a preset heat generation amount threshold value Won (W) and satisfies the formula (4) (that is, the average heat generation amount Wavg is the heat generation amount). If it is equal to or greater than the threshold value Won, the energization unit 4 is controlled in the first suppression mode. In the present embodiment, the heat generation amount threshold Won (shown in FIG. 2) is the heat dissipation amount when the vehicle 3 is in a stopped state.

      Wavg ≧ Won (4)

  In the first suppression mode, the traveling time in the constant speed section is extended from 1 second in the normal time to 3 seconds. By such first suppression mode, the start of acceleration is delayed and the acceleration traveling is suppressed, so that the average heat generation amount Wavg is reduced as compared with the normal time.

  Further, the acceleration suppression unit 7 satisfies the expression (5) after the expression (4) is satisfied (that is, the time X1 (s) in which the average heat generation amount Wavg is equal to or greater than the heat generation amount threshold value Won is the specific unit time X0. In this case, the energization unit 4 is controlled in the second suppression mode.

      X1 ≧ X0 (5)

  In the second suppression mode, when the vehicle 3 is accelerating at the current acceleration / deceleration speed Anx, the acceleration is immediately stopped and the vehicle is switched to deceleration. Specifically, the acceleration suppression unit 7 controls the energization unit 4 so as to supply electric power for traveling at the current speed V1. Then, the vehicle 3 travels at a reduced speed by supplying the electric power. In such a second suppression mode, by partially disabling the travel at acceleration and suppressing the travel at acceleration, the average heat generation amount Wavg is further reduced as compared with the case of the first suppression mode. In the present embodiment, the control in the second suppression mode is effective when the current speed V1 is equal to or higher than a predetermined speed (for example, 1 m / s).

  The acceleration suppression unit 7 cancels the first and second suppression modes in accordance with the average heat generation amount Wavg lowered by the execution of the first and second suppression modes. Specifically, the acceleration suppression unit 7 sets an average heat generation amount Wavg and a preset heat generation amount threshold value Woff (less than the above-described heat generation amount threshold value Won (that is, a threshold value for executing the first suppression mode)). W) and the first and second suppression modes are canceled when the expression (6) is satisfied (that is, when the average heat generation amount Wavg is equal to or less than the release heat generation amount threshold Woff).

      Wavg ≤ Woff (6)

  The conveyance instructing unit 10 includes a processor, a memory, and the like, and is connected to each unit of the traveling control system 100 by wire or wireless, and comprehensively controls each unit of the traveling control system 100. The transport instruction unit 10 instructs the vehicle 3 to transport the FOUP (specifically, the identification number of the FOUP to be transported, the transport source and the transport destination) according to the semiconductor element manufacturing process.

(Acceleration suppression processing)
Next, acceleration suppression processing of the travel control system 100 according to the present embodiment will be described with reference to FIG. FIG. 3 is a flowchart showing the acceleration suppression process according to this embodiment. The acceleration suppression process of the present embodiment is performed once in a control cycle Y0, which is a short time such as several milliseconds or a comma several seconds, for example, while conveyance related to the semiconductor element manufacturing process is instructed.

  In FIG. 3, first, during operation of the traveling control system 100 (see FIG. 1) when the vehicle 3 is traveling or stopped, the heat generation amount specifying unit 5 loads the current speed V1, the current acceleration / deceleration speed Anx, and the FOUP loading. Is detected, and the average calorific value Wavg is specified using equations (1) to (3) (step S50). Then, the acceleration suppression unit 7 determines whether or not the condition of equation (4), that is, the average heat generation amount Wavg is equal to or greater than the heat generation amount threshold value Won (step S51). If the result of this determination is that it is less than the calorific value threshold Won (step S51: NO), the process of step S55 is performed.

  On the other hand, as a result of the determination in step S51, when the average heat generation amount Wavg is equal to or greater than the heat generation amount threshold value Won (step S51: YES), the acceleration suppression unit 7 instructs the energization unit 4 to enter the first suppression mode, The constant speed section is extended by the energization unit 4. At that time, the measurement of the time X1 is started (step S52). Subsequently, it is determined whether or not the time X1 has reached the specific unit time X0 (step S53). As a result of this determination, when the specific unit time X0 has not yet been reached (step S53: NO), a standby state is entered until the specific unit time X0 is reached.

  On the other hand, as a result of the determination in step S53, when the time X1 reaches the specific unit time X0 (step S53: YES), the heat generation amount specifying unit 5 again specifies the average heat generation amount Wavg (step S50), and acceleration is performed. The suppression unit 7 determines whether or not the average heat generation amount Wavg is equal to or greater than the heat generation amount threshold value Won (step S51). If the result of this determination is that it is less than the calorific value threshold Won (step S51: NO), the process of step S55 is performed.

  On the other hand, as a result of the determination in step S51, when the average heat generation amount Wavg is still greater than or equal to the heat generation amount threshold value Won (step S51: YES), the acceleration suppression unit 7 instructs the energization unit 4 to enter the second suppression mode. The running at acceleration is switched to running at deceleration by the energization unit 4 (step S54). Then, the average heat generation amount Wavg and the time X1 are returned to zero (step S55), and a series of acceleration suppression processes are ended.

  As described above, according to the acceleration suppression process of the present embodiment, when the average heat generation amount per specific unit time exceeds the predetermined heat generation amount threshold, the first suppression mode is executed to suppress the traveling with acceleration. To do. Thereby, it becomes possible to suppress the heat generation of the linear motor, which causes a system error. In addition, when the time exceeding the predetermined heat generation amount threshold value is continued even if the predetermined time threshold value is exceeded, the second suppression mode is executed to partially invalidate the traveling at acceleration. Thereby, it becomes possible to further suppress the heat generation.

(Acceleration suppression release processing)
Next, the process (namely, acceleration suppression cancellation | release process) which cancels | releases the 1st and 2nd control of this embodiment is demonstrated with reference to FIG. FIG. 4 is a flowchart showing the acceleration suppression cancellation process according to this embodiment.

  In FIG. 4, after the processing of steps S50 to S55 of FIG. 3 is executed, first, the acceleration suppression unit 7 determines whether or not the first or second suppression mode is being executed (step S61). As a result of this determination, when neither the first suppression mode nor the second suppression mode is being executed (step S61: OFF), the process of step S64 is executed.

  On the other hand, if the result of determination in step S61 is that the first suppression mode is being executed (step S61: ON), the heat generation amount specifying unit 5 specifies the average heat generation amount Wavg in the same manner as in step S50 of FIG. (Step S50), the acceleration suppression unit 7 determines whether or not the condition of Expression (6), that is, whether the average heat generation amount Wavg is equal to or less than the release heat generation amount threshold Woff (Step S62). As a result of this determination, if the amount of heat is greater than the heat generation amount threshold value Woff (step S62: NO), the process of step S64 is performed without releasing the first and second suppression modes.

  On the other hand, if the result of determination in step S62 is that the average heat generation amount Wavg is less than or equal to the heat generation amount threshold value Woff (step S62: YES), the acceleration suppression unit 7 cancels the first suppression mode being executed (that is, off). Then, the extended constant speed section is shortened by the energization unit 4 (step S63). Then, the average heat generation amount Wavg is returned to zero (step S64), and the series of acceleration suppression cancellation processing is ended.

  Thus, according to the acceleration suppression cancellation process of the present embodiment, when the average heat generation amount falls below the cancellation heat generation amount threshold, the first and second suppression modes are canceled and the basic traveling pattern is restored. . As a result, the traveling at the suppressed acceleration is resumed, and the conveyance efficiency of the vehicle 3 is quickly recovered.

  The present invention is not limited to the above-described embodiments, and can be appropriately changed without departing from the spirit or concept of the invention that can be read from the claims and the entire specification.

It is a block diagram which shows the structure of the traveling control system which concerns on embodiment. It is a graph which shows the basic electricity supply pattern and calorie | heat amount of the communication means of FIG. It is a flowchart which shows the acceleration suppression process which concerns on embodiment. It is a flowchart which shows the acceleration suppression cancellation | release process which cancels | releases the 1st and 2nd control which concerns on embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 3 ... Vehicle, 4 ... Current supply part, 5 ... Calorific value specific | specification means, 7 ... Acceleration suppression part, 100 ... Travel control system

Claims (8)

A travel control system that controls the travel of transport means that is driven by a linear motor and can transport an object to be transported,
Energizing means capable of switching energization to the linear motor in order to accelerate, decelerate or drive the conveying means at a constant speed;
A calorific value specifying means for specifying a calorific value from a predetermined time before the present time to the linear motor;
Acceleration suppression means for controlling the energization means so as to switch the energization to the side that suppresses travel during acceleration when the specified heat generation amount exceeds a predetermined heat generation amount threshold value. Running control system.   The acceleration suppression means applies the energization to cause the transport means to travel at the constant speed or the deceleration when the specified heat generation amount exceeds the predetermined heat generation amount threshold during traveling at the acceleration. The travel control system according to claim 1, wherein the energization unit is controlled to be switched. The energizing means is
The energization can be switched to drive the conveying means with acceleration by any one of a plurality of types of acceleration as the conveying means as the acceleration,
The acceleration suppressing means moves the conveying means lower than the current acceleration among the plurality of types of accelerations when the specified heat generation amount exceeds the predetermined heat generation amount threshold during traveling at the acceleration. The travel control system according to claim 1, wherein the energization unit is controlled so as to switch the energization so as to travel by acceleration by acceleration. The energizing means is
The energization can be switched so that the conveying means travels with the acceleration by any one of a plurality of accelerations as the acceleration.
The said electricity supply is switchable so that the said conveyance means can be made to drive by making the said conveyance means into the said deceleration by the deceleration by a single deceleration. The Claim 1 characterized by the above-mentioned. Traveling control system. The acceleration suppression means controls the energization means to switch the energization to the side that extends the time for running at the constant speed or to maintain the energization when the predetermined heat generation amount threshold is exceeded. The travel control system according to claim 1, wherein: The acceleration suppression means includes
The energization means is controlled to switch the energization to the side to run at the deceleration when the state exceeding the predetermined heat generation amount threshold is still continued even if the predetermined time threshold is exceeded. The travel control system according to claim 5. The calorific value specifying means includes the current speed of the transport means, the current acceleration or deceleration of the transport means traveling at the current speed, and the object being transported by the transport means traveling at the current speed. The travel control system according to any one of claims 1 to 6, wherein the heat generation amount is specified based on presence or absence of a conveyed product. The travel control system according to any one of claims 1 to 7, wherein the heat generation amount specifying unit specifies, as the heat generation amount, an average value of a heat generation amount from the predetermined time before to the present time. .

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