JP2001078423A - Carrier driven by linear induction motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid overheating of the secondary mover of a linear induction motor mounted on a carrier, using a simple construction. SOLUTION: Respective left and right pairs of traveling wheels 4 and left and right pairs of guide wheels 5 are attached to a body 3 of a carrier 1. The guide wheels 5 are attached rotatably in the horizontal plane and brought into contact with the wall surfaces 2a of a guide channel 2, to restrict the sidewise movement of the carrier 1. A primary side stator 9, of which a linear induction motor is composed, is provided on the bottom of the guide channel 2. The body 3 has a cylindrical shape which is extend in front and rear directions and its bottom part is opened. A reaction plate 10, of which the linear induction motor is composed together with the primary side stator 9, is mounted on the body 3 so as to close the opening of the bottom. Radiation fins 11, made of aluminum are fixed to the upper surface of the reaction plate 10. A hollow part 12 formed in the body 3 functions as an air flow guide which guides an air flow to the radiation fins, while the carrier 1 is traveling.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear induction motor driven carrier equipped with a secondary movable element constituting a linear induction motor together with a primary stator provided along a traveling route.

[0002]

2. Description of the Related Art In recent years, a linear motor driven transport vehicle using a linear induction motor as a drive source for transporting articles in a factory has been proposed and implemented. When a linear induction motor is used as a drive source, there are a configuration in which a secondary movable element (secondary conductor) is provided on the transport vehicle side and a configuration in which a primary movable element is provided on the transport vehicle side. As a configuration in which a secondary conductor is provided on the side of a carrier, Japanese Patent Application Laid-Open No. Hei 5-22926 discloses a configuration shown in FIG. That is, a movable member (conveyor) 43 having a U-shaped cross section is movably supported via a traveling wheel 44 along a guide rail 42 attached to a support member 41 constituting a traveling route. An armature core 45a is provided on the support member 41.
A primary stator 45 including an armature winding 45b is provided, and the movable member 43 is provided with a secondary conductor 46 made of an aluminum plate at a position facing the primary stator 45.

In Japanese Patent Application Laid-Open No. 2-220964, as shown in FIG. 6, a primary movable element 49 is provided on a side of a carriage (transportation body) 48 traveling along a rail 47, and a track surface (running route) is provided. ) On the 50 side, a belt-shaped reaction plate 51 as a secondary stator is disposed. When the primary mover (coil) is provided on the carriage 48,
It is necessary to provide a cover to prevent pebbles from colliding with the end of the coil during traveling.However, if the cover is provided, the heat generated from the coil during energization becomes difficult to escape to the outside, and the output of the linear motor is reduced. This leads to a decline.

In this device, as a cooling device for a linear motor, as shown in FIGS. 6 and 7, a protective cover 54 covering a protruding portion 52a of a coil 52 of a primary mover 49 from a laminated iron core 53 has a large number of holes. An outside air inlet 56 is formed, which is formed at the same time as the outer cover 55. When the truck 48 travels, for example, rightward in FIG. 7, the protruding portion 52 a of the coil 52 is cooled by air that has entered the protective cover 54 from the hole 55 and the outside air intake 56. .

[0005]

Conventionally, when a primary side stator is provided on a carrier, the heat generation of the coil is taken into consideration.
Cooling was considered to avoid overheating the primary stator. However, in the case where the secondary mover (secondary conductor) is provided on the carrier, cooling of the secondary mover has not been considered.

[0006] Even the secondary-side mover without a coil generates heat, and when the amount of heat generation increases, thermal deformation of the components of the carrier, thermal effects on the load of the carrier, or a change in the resistance of the secondary-side conductor. There are inconveniences such as reduced thrust. Conventionally, no problem has occurred because the acceleration and the maximum speed of the carrier are set within a range in which heat generation of the secondary side conductor hardly causes a problem. However, if the acceleration is made higher or the maximum speed is made higher in order to increase the transfer efficiency of the transfer body, the above-described problem occurs.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to drive a linear induction motor which can prevent overheating of a secondary movable element of a linear induction motor mounted on a carrier with a simple configuration. An object of the present invention is to provide a transport vehicle.

[0008]

In order to achieve the above object, according to the first aspect of the present invention, a secondary mover which forms a linear induction motor together with a primary stator provided along a traveling route. Wherein a radiation fin is fixed to the secondary-side movable element, and an airflow guide that guides an airflow to the radiation fin when the transportation vehicle travels is provided.

According to a second aspect of the present invention, in the first aspect of the present invention, the radiating fins are integrally formed of the same material as the secondary movable element. According to a third aspect of the present invention, in the first aspect of the invention, the secondary mover is made of a non-magnetic metal, and the radiation fin is made of a ferromagnetic material.

Therefore, according to the first aspect of the present invention, the carrier carries the secondary mover of the linear motor as a drive source and travels along the traveling route. The air flow guided to the air flow guide when the transport vehicle travels flows so as to cool the radiation fins fixed to the secondary-side mover. As a result, even at the time of high acceleration or the highest speed, overheating of the secondary mover is prevented.

According to the second aspect of the present invention, in the first aspect of the present invention, since the radiation fin is integrally formed of the same material as the secondary-side movable element, manufacture and assembly are facilitated, and The manufacturing cost of the induction motor driven carrier is reduced.

According to a third aspect of the present invention, in the first aspect of the present invention, the secondary mover is made of a non-magnetic metal and the radiation fin is made of a ferromagnetic material. The thrust increases with the same amount of current as compared to the case where the whole is formed of a non-magnetic conductor.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. FIG. 1A is a schematic front view of the carrier 1, and FIG.
It is a B sectional view.

As shown in FIG. 1 (a), a transport vehicle 1 travels in a guide groove 2 forming a travel route. The vehicle body 3 of the carrier 1 is provided with a pair of left and right traveling wheels 4 and guide wheels 5. Guide wheel 5 is bracket 6
In addition, the guide shaft 2 is rotatably mounted in a horizontal plane via a support shaft 7, and comes into contact with the wall surface 2a of the guide groove 2 to restrict the movement of the carrier 1 in the width direction.

A housing portion 8 is provided at the bottom of the guide groove 2 one step lower. A primary stator 9 constituting a linear induction motor is provided in the housing portion 8. The vehicle body 3 is formed in a cylindrical shape extending in the front-rear direction, and is formed in an open bottom shape. In the vehicle body 3, so as to cover the bottom opening,
A reaction plate 10 is mounted as a secondary movable element that forms a linear induction motor together with the primary stator 9. The reaction plate 10 is formed of an aluminum plate.

A radiation fin 11 made of aluminum is fixed to the upper surface of the reaction plate 10. Body 3
The hollow portion 12 formed as a function as an airflow guide for guiding the airflow to the radiation fins 11 when the carrier 1 travels.

The primary stator 9 is connected to a control device 13. The control device 13 includes a CPU and a memory (neither is shown). The control device 13 controls the amount of current supplied to the primary stator 9 based on a command signal from a higher-level control device (for example, a control device of a transport system equipped with the transport vehicle 1), and accelerates the transport vehicle 1.・ Deceleration and stop control are performed.

Next, the operation of the carrier 1 configured as described above will be described. When the primary side stator 9 is energized, an eddy current is induced in the reaction plate 10 at a corresponding position by the traveling magnetic field generated by the primary side stator 9, and the eddy current and the traveling magnetic field act on the reaction plate 10, thereby causing the left hand of Fleming to operate. The driving force of the carrier 1 is generated by the law. Reaction plate 10
Has an electrical resistance, and generates heat when an eddy current flows.
Although there is no problem when the heat generation amount is small, the heat generation amount increases when the acceleration is increased or the maximum speed is increased.

If the amount of heat generation is large, unless the heat is efficiently dissipated, overheating of the reaction plate 10 causes thermal deformation of vehicle body components and adverse effects of heat on the components mounted on the transport vehicle. Further, when the resistance value increases due to overheating, eddy current becomes difficult to flow, and the thrust decreases. Further, when the vector control is used for controlling the motor, the resistance value of the reaction plate 10 becomes a control parameter in the vector control, but it is difficult to control with high accuracy because the resistance value fluctuates due to heat.

However, in this embodiment, since the radiation fins 11 are fixed to the reaction plate 10,
The heat generated in the reaction plate 10 is immediately transmitted to the radiation fins 11 and is efficiently radiated through the radiation fins 11. Further, when the carrier 1 travels, the radiation fins 11
The air flow is guided to the hollow portion 12 in which is disposed, and the heat of the radiation fins 11 is efficiently removed by the air flow. Therefore,
Due to the high acceleration or high-speed running, even if the heat value of the reaction plate 10 becomes large, the reaction plate 1
Zero overheating is prevented.

When the radiation fins 11 are provided, the reaction plate 10 without the radiation fins 11 is provided on the same carrier 1.
2, the relationship between the time and the temperature of the reaction plate 10 when the carrier 1 is running at high speed is as shown in FIG. 2. When the heat radiation fins 11 were not provided, the temperature became higher than the minimum temperature T at which the overheating had an adverse effect. However, when the heat radiation fins 11 were present, the temperature did not reach the temperature at which the overheating had an adverse effect.

This embodiment has the following effects. (1) An air flow guide (hollow portion 12) in which a radiation fin 11 is fixed to a secondary mover (reaction plate 10) mounted on the carrier 1 and guides an air flow to the radiation fin 11 when the carrier 1 travels. Was provided. Therefore, the heat generated in the reaction plate 10 is efficiently dissipated through the radiating fins 11, and the overheating of the reaction plate 10 is prevented even when the amount of heat generated by the reaction plate 10 increases during high acceleration or high-speed running. As a result, it is possible to prevent the thermal deformation of the vehicle body components and the adverse effect of the heat on the load of the transport vehicle 1 due to the overheating of the reaction plate 10. Also,
The change in the resistance value of the reaction plate 10 is small, and the speed and the position of the carrier 1 can be controlled with high accuracy.

(2) Since the radiation fins 11 are formed of the same material as the reaction plate 10, it is easy to fix them together in a state where they are in close contact with each other. (3) Since the hollow portion 12 formed in the vehicle body 3 forms an airflow guide, the structure of the airflow guide is simple, and the airflow can be efficiently guided to the radiating fins 11.

(4) Since the reaction plate 10 and the radiating fins 11 are made of aluminum, they are lighter in weight and workability in assembling is better than those made of copper or combined with iron.

(5) The transport vehicle 1 travels in a guide groove 2 for guiding guide wheels 5 provided on both left and right sides of the transport vehicle 1. Therefore, as compared with the configuration in which the vehicle travels while being guided by the guide provided at the position corresponding to the center in the width direction of the transport vehicle 1,
The degree of freedom in the location where the reaction plate 10 of the linear motor mounted on the carrier 1 is installed is increased.

The embodiment is not limited to the above, and may be embodied as follows, for example. The radiation fins 11 and the reaction plate 10 may be integrally formed of the same material (for example, aluminum) as shown in FIG. In this case, as compared with the case where both are formed separately and fixedly adhered to each other, the manufacturing is simplified and the assembling work is also simplified, so that the manufacturing cost of the linear motor driven transport vehicle is reduced. In the case of aluminum, it can be easily manufactured by extrusion molding.

As shown in FIG. 4, the reaction plate 10 may be made of a non-magnetic metal, and the radiation fin 11 may be made of a ferromagnetic material (for example, iron) so that the radiation fin 11 has a function as a back yoke. Good. In this case, the thrust is increased with the same amount of current as compared with the case where both are formed of nonmagnetic conductors.

The vehicle body 3 is not limited to a cylindrical shape, but is formed in a box shape and has a passage or a hole for communicating a space for accommodating the radiating fins 11 with the outside, and takes in external air from the passage or the hole during traveling. Is provided. In this case, the passage or hole and the assisting member constitute an airflow guide.

○ The transport vehicle 1 is mounted on the reaction plate 10
Grooves or slits extending in a direction perpendicular to the traveling direction of the vehicle may be formed at a predetermined pitch. In this case, the eddy current generated in the reaction plate 10 recirculates around the groove or slit, and the linear induction motor efficiently generates thrust.

The transport vehicle 1 is not limited to a configuration in which the pair of left and right guide wheels 5 move along the guide grooves 2, and may include a configuration having guide wheels that sandwich a guide rail provided at the center of the traveling path, and a track. It may be configured to run on (rail).

The carrier 1 is not limited to the configuration having the traveling wheels 4 but may be a floating type having no traveling wheels. Technical ideas (inventions) other than those described in claims that can be grasped from the embodiment
Is described below together with its effects.

(1) In the first or second aspect of the invention, the secondary mover and the radiation fin are made of aluminum. In this case, it is lighter in weight and easier to process and handle than other metals.

(2) In the invention according to any one of the first to third aspects, the heat radiation fins are housed in a tubular body extending in the traveling direction of the carrier, and the hollow portion of the tubular body is air. Functions as a flow guide. In this case, the structure of the air flow guide is simple, and the attachment of the radiation fin is also simple.

[0034]

As described above in detail, according to the first to third aspects of the present invention, overheating of the secondary side mover of the linear induction motor mounted on the carrier can be prevented with a simple configuration. ,
Accurate control can be performed even during high acceleration and running at the highest speed.

According to the second aspect of the present invention, manufacture and assembly are facilitated, and the manufacturing cost can be reduced. According to the third aspect of the present invention, the thrust can be increased with the same amount of current as compared with the case where the entire secondary side mover is formed of a nonmagnetic conductor.

[Brief description of the drawings]

FIG. 1A is a schematic front view of a carrier according to an embodiment, and FIG. 1B is a cross-sectional view taken along the line BB of FIG.

FIG. 2 is a graph showing a temperature change of a secondary conductor.

FIG. 3 is a schematic perspective view of a radiation fin according to another embodiment.

FIG. 4 is a schematic front view of a radiation fin according to another embodiment.

FIG. 5 is a schematic view of a conventional linear motor carrier.

FIG. 6 is a cross-sectional view of another conventional device.

FIG. 7 is a sectional view of a main part of the same.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Conveyance vehicle, 2 ... Guide groove which comprises a traveling route, 9 ... Primary stator, 10 ... Reaction plate as secondary movable element, 11 ... Heat radiation fin, 12 ... Hollow part as air flow guide.

Claims (3)

[Claims] 1. A carrier equipped with a secondary mover constituting a linear induction motor together with a primary stator provided along a traveling path, wherein a radiation fin is fixed to the secondary mover. A linear induction motor driven transport vehicle provided with an airflow guide for guiding an airflow to the radiation fins when the transport vehicle travels. 2. The linear motor driven transport vehicle according to claim 1, wherein the radiation fins are integrally formed of the same material as the secondary mover. 3. The linear motor driven transport vehicle according to claim 1, wherein the secondary mover is made of a non-magnetic metal, and the radiation fin is made of a ferromagnetic material.