JPH0517028A - Control method for vertical transport device - Google Patents

Abstract

PURPOSE:To make truck stop positions accurate by accelerating trucks by means of the propelling power sum of two linear motors at the time of start, moving two trucks by means of the thrust of a linear motor alone that is opposite to one side truck, before stop. CONSTITUTION:A drive control portion gives brake power that consists of the reverse direction thrust sum of two linear motors, to trucks 3a, 3b. As a result, trucks 3a, 3b, in comparison with a case in which one side linear motor alone is operated, are decelerated to the lowest speed at a shorter deceleration section. Next, the drive control portion, at the time point when trucks 3a, 3b have reached predetermined stop positions, stops the operation of one side linear motor that has been kept operating at a section before stop. As a result, there is no drive power to trucks 3a, 3b, and trucks 5a, 5b stop at stop positions. When the movement of vertical transport device I trucks is controlled as above, trucks 3a, 3b can be moved to stop positions in a short time, and also stopped at accurate positions.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vertical transfer device installed in a building or the like for mainly transferring a fixed object such as a document file in a vertical direction.

[0002]

2. Description of the Related Art As an apparatus for moving a trolley by vertically moving a trolley, for example, there is one disclosed in Japanese Patent Publication No. 54-11194. As shown in FIG. 6, the device disclosed herein hangs a wire 62 via a pulley 61, and a trolley 63 serving as a counterweight is provided at one end of the wire 62.
And the linear motor 64 is hung at the other end. However, since such a device controls the movement of the bogie in both up and down directions with one linear motor, a large linear motor is required to obtain the necessary thrust, and the device becomes large. There was a problem. Conversely, unless the linear motor is upsized, the weight limit of luggage is relatively light.

In order to solve such a problem, the applicant of the present application has disclosed in Japanese Unexamined Patent Publication (Kokai) No. 3-31119 a guide plate which is vertically installed and has secondary conductors of a linear motor on the front surface and the back surface, respectively, and this guide plate. A pulley installed above the guide plate, a rope hanging down to the front surface side and the back surface side of the guide plate through the pulley, and connected to the rope and run along the front surface and the back surface of the guide plate, respectively. Two trolleys are provided, and each trolley has a primary winding of a linear motor that can be driven in both up and down directions.
A vertical transfer device is proposed which controls the vertical movement of the two carriages by driving the linear motors of the carriages in opposite directions. According to such a vertical transport device, when transporting an object of the same weight, the linear motor used is a linear motor that generates a thrust that is half that of the linear motor 64 used in the conventional vertical transport device as shown in FIG. Good. Further, if a linear motor that generates the same thrust as that of the linear motor 64 is used, it is possible to convey a conveyed object having a heavier weight than that of the conveying device shown in FIG.

In the vertical transport apparatus as described above, a time chart when the carriage is vertically moved by controlling the linear motor is generally as shown in FIG. As shown in FIG. 4, the time chart for moving the bogie from the start position to the stop position is the acceleration section (A) in which the linear motor is activated to accelerate the moving speed of the bogie.
And a constant speed section (B) in which the truck is moved at a constant maximum speed
And a deceleration section (C) for reducing the speed of the truck and a pre-stop section (D) for moving the truck at a constant minimum speed.
When the truck is driven according to such a time chart, the linear motor is ON / OFF controlled. When the linear motor is ON / OFF controlled in this way, the ON
It is possible to obtain a pulse-like thrust force as shown in FIG. That is, the thrust of the linear motor can be controlled by changing the width t or height h of each pulse waveform in FIG.

[0005]

By the way, in the above-described vertical transfer apparatus, it is effective to move the carriage from the starting position to the stopping position in the shortest possible time. That is, in the control of the vertical transfer device performed according to the time chart of Fig. 4, the time between the acceleration section (A) and the deceleration section (C) is shortened as much as possible, and the constant speed section (B) in which the truck travels at the maximum speed is set. It is preferable to lengthen the time. On the other hand, in the control of the vertical transport device, in order to accurately stop the carriage at a predetermined stop position,
It is preferable to keep the speed of (D) as small as possible. On the other hand, in the above-described vertical transfer device disclosed in Japanese Patent Laid-Open No. 3-31119, the two carriages are moved by driving the linear motors of the two carriages in opposite directions. Therefore, as mentioned above,
The thrust for moving the two carriages is the sum of the thrusts of the two linear motors. Therefore, although the time between the acceleration section (A) and the deceleration section (C) can be shortened, the speed in the pre-stop section (D) cannot be sufficiently reduced. That is, although the work efficiency can be improved, there is a problem that it is difficult to perform accurate positioning at the time of stop.

The above problems are caused by turning on the linear motor.
This is because the width t of the pulse waveform in FIG. 5 described above cannot be reduced to a certain extent or more due to the relationship between elements such as the SSR used for turning on / off. That is, in order to sufficiently reduce the speed in the pre-stop section (D), it is necessary to reduce the height h of the pulse waveform in FIG.

The present invention has been made in view of the above circumstances, and provides a control method for a vertical transfer device capable of shortening the time of the acceleration section and the deceleration section and performing accurate positioning when stopped. Is intended.

[0008]

A method of controlling a vertical conveyor according to claim 1 which achieves the above object, comprises vertically arranging guide plates each having a secondary conductor of a linear motor on a front surface and a back surface of the guide plate. A power transmission wheel is installed above the plate, and a linear body that hangs down on the front surface side and the back surface side of the guide plate is wrapped around the power transmission wheel, and the linear body is attached to the front surface and the back surface of the guide plate. A control method for a vertical transfer device, wherein each of the carts is capable of traveling in the vertical direction, and each of the carts is provided with a primary winding of a linear motor for driving the carts in the vertical direction. Drive the bogies in the opposite directions by controlling the linear motors corresponding to the bogies to generate thrusts in opposite directions, and before stopping, use only the linear motors corresponding to one of the bogies to drive both bogies. It is characterized in that drive.

Further, the control method of the vertical conveyor according to a second aspect of the present invention is the control method according to the first aspect, wherein the moving speed of both carriages is reduced by switching the thrust of the linear motor corresponding to each carriage in the direction opposite to the starting direction. After that, the thrust of the linear motor corresponding to one of the bogies is switched to the opposite direction again, and the thrust of the linear motor corresponding to the other bogie is set to zero. The feature is that both carriages are driven by the thrust of only the motor.

[0010]

According to the control method of the vertical carrying apparatus of claim 1,
When the vehicle is started, the vehicle is accelerated by the sum of the thrusts of the two linear motors, so that the vehicle can approach the stop position in a short time. Further, before stopping, the two carriages are moved by the thrust of only the linear motor corresponding to one of the carriages, so the moving speed of the carriage is made smaller than that when the carriages are moved by the thrusts of the two linear motors. be able to.

According to the control method of the vertical carrying device of the second aspect, the traveling speed of the carriage is reduced in a short time by simultaneously reversing the directions of the thrusts by the two linear motors.

[0012]

1 is a perspective view showing an apparatus main body I of a vertical transfer apparatus to which a control method according to the present invention is applied. A device main body I of this vertical transport device includes a rail plate (guide plate) 1 which is vertically erected, pulleys 2a and 2b provided above and below the rail plate 1, and a front surface side of the rail plate 1. Two carriages 3a and 3b, which travel on the back side and
Two carriages 3a, 3 via pulleys 2a, 2b respectively
It is provided with wire ropes 4a and 4b which connect b to each other.

The carriages 3a and 3b each have a primary winding (not shown in FIG. 1) of a linear motor built therein. Also,
The rail plate 1 has a parallel plate-shaped substrate 11,
A secondary conductor 12 of a linear motor and a power feed line 13 are arranged in the vertical direction (longitudinal direction of the substrate 11) on each of the front surface and the back surface. Then, both end portions of the surface of the substrate 11 are rail surfaces 14 on which the wheels of the carriage 3a travel.
a and 14b. The same applies to the back surface of the substrate 11.

FIG. 2 is a sectional view showing the positional relationship between the rail plate 1 and the carriage 3a. In the figure, the primary winding 31 of the truck 3 a is provided at a position facing the secondary conductor 12 of the rail plate 1. The trolley 3a is provided with four wheels 32, and these wheels 32 travel on the rail surfaces 14a and 14b. Further, the brush 33 of the carriage 3a slides on the power supply line 13 of the rail plate 1 to receive power. Dolly 3a
Guide wheels 34a to 34c are provided on both side surfaces of the rail plate 1.
By running inside a U-shaped rail 40 that is erected in parallel with, the gap between the primary winding 31 and the secondary conductor 12 is kept within a predetermined range, and the linear motor can be operated efficiently. ing. The above configuration is the same for the truck 3b, and the linear motors corresponding to the trucks 3a and 3b can obtain the same thrust.

The vertical transport device is a device for vertically transporting a standard product such as a document file (hereinafter referred to as a transport product). Therefore, as shown in FIG. 1, the carriage 3a (and 3b) is mounted on the horizontal transfer device (belt 3B) for mounting the conveyed product F and moving the conveyed product F in the ± x directions as necessary. Conveyor 50). 51
Is a departure buffer for loading the article F into the vertical transport device at a position of a predetermined height, and 52 is a departure buffer 51.
It is an arrival buffer for taking out the conveyed product F at a position higher than the predetermined height.

The apparatus main body I of the vertical transfer apparatus shown in FIGS. 1 and 2 is controlled by the drive control unit II shown in FIG.
The drive control unit II detects the rotation amount of the pulley 2b by a rotation detector III such as a rotary encoder, and detects the positions of the carriages 3a and 3b based on the rotation amount. Then, the drive control unit II is configured to detect the preset stop position and the carriages 3a and 3b detected as described above.
Based on the position of, the moving speed of the carriages 3a and 3b from the start position to the stop position is controlled. The control of the moving speed is performed according to the time chart as shown in FIG. 4 described above by controlling the voltage applied to the primary windings of the linear motors of the carriages 3a and 3b in the procedure described later. Is done. As described above, the time chart of FIG. 4 shows the acceleration section in which the carriages 3a and 3b are accelerated.
(A), a constant speed section (B) for moving the trucks 3a, 3b at a constant maximum speed, a deceleration section (C) for reducing the speed of the trucks 3a, 3b, and a constant minimum speed for the trucks 3a, 3b. It has a pre-stop section (D) that is moved by.

In the acceleration section (A) and the constant speed section (B), the drive control section II makes the carts 3a, 3b in opposite directions (for example, one of the carts 3a, 3b) by the thrust of the two linear motors provided in the carts 3a, 3b. The trolley 3a is in the downward direction, the other trolley 3
b is moved upward). Assuming that the thrust force by one of the linear motors is f, the thrust force for moving the trucks 3a and 3b in the acceleration section (A) and the constant speed section (B) is as shown in FIG.
As shown in (a), the sum of thrusts of two linear motors is 2
f. When the trolleys 3a and 3b are driven by the sum of the thrusts of the two linear motors in this way, the trolleys 3a and 3b are driven in a shorter time in the acceleration section (A) than when driven by the thrust of only one of the linear motors. The maximum speed set in the constant speed section (B) can be set higher than that when only one of the linear motors is operated. Therefore, the time required for the acceleration section (A) and the constant speed section (B) is shortened as compared with the case where only one linear motor is operated.

Next, the drive control unit II is configured to control the deceleration section.
In (C), the direction of thrust by both linear motors is reversed from the direction of thrust in the acceleration section (A) and constant speed section (B), as shown in Fig. 5 (b) for the carriages 3a and 3b. A braking force that is the sum of thrusts in the opposite directions by two linear motors is applied. As a result, the carriages 3a and 3b are decelerated to a predetermined minimum speed in a shorter deceleration section (C) than when only one of the linear motors is operated.

Next, the drive control unit II
In (D), the operation of one of the linear motors is stopped, and the direction of thrust by the other linear motor is reversed again. In other words, in this pre-stop section (D), the two trucks 3a,
3b is driven. Therefore, as shown in FIG. 5C, the width t of the pulse waveform is made as small as possible to minimize the thrust of the linear motor on the operating side, whereby a sufficiently low minimum speed can be obtained.

Next, the drive control section II stops the operation of one of the linear motors that were operating in the pre-stop section (D) when the carriages 3a, 3b reach a predetermined stop position. As a result, the driving force for the carriages 3a and 3b is lost, and the carriages 3a and 3b stop at the stop position. As described above, since the speeds of the carriages 3a and 3b in the pre-stop section (d) are the sufficiently low minimum speeds, the carriages 3a and 3b are stopped by stopping the operation of the linear motor on the operating side.
Can be accurately stopped at a predetermined stop position. If both linear motors are operated in the pre-stop section (D), the minimum speed in the pre-stop section (D) increases as shown by the alternate long and short dash line in Fig. 4, and the carriages 3a and 3b are accurately moved. It becomes difficult to stop it in place.

As described above, by controlling the movement of the carriages of the vertical carrier by the above method, the carriages 3a and 3b can be moved to the stop positions in a short time, but the carriages 3a and 3b are moved. It can be accurately stopped at a predetermined stop position.

The configuration of the vertical transfer apparatus to which the above control method is applied is not necessarily limited to the apparatus shown in FIG. 1 or 2. For example, the pulleys 2a and 2b and the ropes 4a and 4b may be changed to sprockets and chains. In addition, the lower pulley 2 has only the upper pulley 2a.
It may be a vertical transfer device that does not include b.

[0023]

According to the first aspect of the present invention, even though the trolley can approach the stop position in a short time and high work efficiency can be obtained, the moving speed of the trolley is made sufficiently small before the stop. An effect that the lever cart can be stopped at an accurate stop position is obtained.

According to the second aspect, the carriage can be decelerated in an extremely short time, and the carriage can be brought closer to the stop position in a shorter time.

[Brief description of drawings]

FIG. 1 is a perspective view of a device body of a vertical transport device.

FIG. 2 is a cross-sectional view of a main part of the apparatus body of FIG.

FIG. 3 is a configuration diagram of a vertical transport device.

FIG. 4 is a time chart showing a moving process of the carriage.

5 is a diagram showing a thrust generation state by a linear motor in each section in the time chart of FIG.

FIG. 6 is a schematic side view of a device body of a conventional vertical transport device.

[Explanation of symbols]

1 Rail plate (guide plate) 2a Pulley (wheel for power transmission) 3a, 3b dolly 4a rope (striated body) 12 Secondary conductor 31 primary winding

Claims (2)

[Claims] 1. A guide plate having a secondary conductor of a linear motor is erected vertically on the front surface and the back surface, and a power transmission wheel is provided above the guide plate. Wrap a linear body that hangs down on the front surface side and the back surface side, and connect the carriage that can travel in the vertical direction on the front surface and the back surface of the guide plate to the linear body,
A control method for a vertical conveyance device, wherein each trolley is provided with a primary winding of a linear motor for driving these trolleys in a vertical direction, and the linear motors corresponding to the trolleys are driven in opposite directions when starting. The vertical conveyance is characterized in that each carriage is driven in the opposite direction by controlling so as to generate the thrust of each carriage, and before stopping, both carriages are driven by the thrust of only the linear motor corresponding to one of the carriages. Device control method. 2. The moving speed of both carriages is reduced by switching the thrust of the linear motor corresponding to each carriage in the opposite direction to that at the start, and then the thrust of the linear motor corresponding to one of the carriages is reversed in the opposite direction. The two trolleys are driven by the thrust of only the linear motor corresponding to one of the trolleys before the stop by switching and making the thrust of the linear motor corresponding to the other trolley to zero. Control method for vertical transfer device.