JPH04274961A - Device and method for moving article - Google Patents

Abstract

PURPOSE: To change the speed of a specific vehicle without changing the speed of the other vehicle by providing a rail with a magnetic strip having alternating regions of flux and no-flux, and sensing the alternating flux regions as a vehicle moves on the rail. CONSTITUTION: A magnetic strip 72 is magnetized to provide alternating N-poles and S-poles supplying alternating regions of magnetic flux. As a vehicle 10 moves along a rail 12, sensors 74, 76 sense the presence of alternating flux regions of the magnetized strip 72 and output open or closed circuits in response to the presence of flux. The sensors 74, 76 are connected to a microcontroller 90 through wires 78, 80, and the number of open or closed circuits is counted to compute the speed, position and/or displacement of the vehicle 10. The micro- controller 90 controls the speed of a trolley motor 94 so as to attain specified speed based on an input reference signal through a speed regulator such as an adjustable frequency drive 92.

Description

[Detailed description of the invention]

0001

TECHNICAL FIELD This invention relates to rail attachment systems using vehicles for transporting goods, such as in elevated track trolley systems, and more particularly to rail attachment systems that utilize one or more operating characteristics of the vehicle in relation to the rail during operation. It pertains to the device and method for determining.

0002

BACKGROUND OF THE INVENTION Rail-mounted vehicle systems are used in numerous applications such as automated material storage and retrieval equipment, assembly line parts handling equipment, automated assembly lines employing robots, and the like. In systems where vehicles are used on rails, it is usually important to be aware of one or more operating characteristics of the vehicle relative to the rails. For example, in multi-vehicle systems, such as assembly line part handling applications or factory automation applications, it is desirable to maintain proper spacing between vehicles and tightly control the speed of the vehicles on the rails. As another example, in material storage and retrieval equipment, it is important to know the location of vehicles on the rails.

One known device for maintaining proper vehicle spacing involves the use of chains or the like and attaching each vehicle to the chain at a distance. While this type of device ensures proper spacing, it is a fixed device. For example, it is not possible to change the speed of one vehicle without changing the speed of all vehicles.

Other known devices use barcodes and readers, where the barcode is applied to the rail and the reader is mounted on the vehicle. While this type of device provides more versatility, it has the disadvantage that dirt or other foreign material on the bar code may prevent the reader from properly reading it. This results in poor performance.

[0005]

SUMMARY OF THE INVENTION The present invention is used with one or more vehicles movable on rails, such as electric trolley systems. In such devices, the vehicle is typically attached to a rail by one or more wheels;
An electric motor is mounted on the vehicle to drive one or more wheels. Electrical devices are attached to the rail to provide electrical current along the length of the rail. The vehicle is
A pickup is provided that is connectable to an electrical device that supplies power to an electric motor to move the vehicle along the length of the rail.

[0006]

SUMMARY OF THE INVENTION In accordance with the invention, fixed magnetic means are mounted on the rail and the magnetic means is provided with alternating magnetic flux regions oriented non-parallel to the direction of movement of the vehicle on the rail. If desired, the non-flux regions may be arranged between adjacent regions of alternating magnetic flux, and the sensor means are mounted on the vehicle and movable therewith. The sensor means is operative to sense the presence or absence of a magnetic flux region provided in the magnetic means;
It outputs a signal in response. Means responsive to the sensor output signal is provided for determining one or more operating characteristics of a vehicle associated with the rail. In a preferred embodiment, the magnetic means comprises an axially extending magnetic strip attached to and extending along the rail, the alternating magnetic flux regions oriented substantially perpendicular to the direction of movement of the vehicle on the rail. . The sensor means outputs an open circuit in response to a direction of the magnetic field above a predetermined threshold, which occurs each time it passes one of the magnetized regions on the magnetic strip. The means responsive to the sensor output signals preferably comprises a microprocessor, a programmable controller, or the like. This part of the device serves to count the number of output signals output by the sensor means, and this information determines the vehicle speed and the position of the vehicle on the rail and/or the displacement of the vehicle from a given point. Processed to do so.

In one embodiment, power is supplied to the vehicle motor by one or more conductor bars attached to the rail. In addition, the conductor bar transfers power to the vehicle control device,
Provides ground potential to the vehicle motor. The magnetic strip is attached to a conductor bar and the sensor means is assembled into a pick-up or collector which is preferably connectable with a conductor bar commonly used to supply ground potential to a vehicle motor. In one preferred arrangement, the conductor bar is provided with an axial path along its length, and the magnetic strip is physically located within the axial path. In this way, the magnetic strip is covered and is not subject to wear, but alternating regions of magnetic flux and non-magnetic flux can be detected via the conductor bar by a sensor provided in the pickup.

The invention also relates to a method of determining one or more operating characteristics of a vehicle in relation to a rail substantially in accordance with the above.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an elevated electrified trolley system in which a vehicle, generally indicated at 10, is mounted on a rail, indicated generally at 12. Vehicle 10 is shown as carrying an industrial robot 13, the details of which are not important to the invention. While vehicle 10 and rails 12 are shown in a factory automation system, it is understood that vehicle 10 and rails 12 may be used in any satisfactory application involving the movement of items on a predetermined route from one point to another.

As shown, vehicle 10 includes a lower frame 14 having a pair of vertical support members 16, 18 extending upwardly therefrom. A pair of horizontal supports 20, 22 are connected to vertical supports 16, 18, respectively, and a pair of wheels (not shown) are connected to each of horizontal supports 20, 22. The wheels move on top of the rails 12 to move the vehicle 10 on the rails 12. As shown, vehicle 10 includes an electric motor (not shown) operable to move wheels on rails 12 to move vehicle 10 .

A multi-conductor electrification device, generally indicated at 24, is provided between the flanges of rail 12. The electric device 24 is 26,
A plurality of conductor bars such as 28, 30 and 32 are shown. Conductor bars 26-32 provide electrical power to the vehicle motor, control signals to the controller, and ground potential to the vehicle. This type of rail electrification equipment is available, for example, from Electromotive Systems, Inc., Milwaukee, Wisconsin, under the name FABA100.
Anything sold at is fine.

[0012] The box 34 is attached to the vehicle 10, and
It includes a plurality of conductor bar contacts of a pickup, commonly referred to as a collector, that interfaces with the conductor bars 26-32 to provide power from the conductor bars 26-32 to the vehicle electric motor. Box 34 includes a plurality of pickup members, shown at 36, wired to the electric motor to supply power or ground potential thereto.

Referring to FIG. 2, the interface between electrification device 24 and pickup 36 is shown in more detail. As shown, conductor bar 32 includes an outwardly facing contact surface 38 that is housed and protected within a plastic bar holder or hanger 40.

The pickup member 36 includes a bracket 42 through which the pickup 36 is attached to the vehicle 10 by a support member 44. Arm member 46 is connected to bracket 42 . Each end of the arm member 46 has a 48
, 50 is provided. Contact holders 48 and 50 each have contacts 52 and 52 attached thereto, respectively.
54 included. The external contact surfaces of the contacts 52, 54 are engaged with the contact surface 38 of the conductor bar 32, which supplies power, control signals and/or ground potential vehicle electric motors and their controllers via wires 56, 58, respectively.

Referring to FIG. 3, the contact surface 38 is connected to the inner wall 6.
6 indicates the outwardly facing surface of the inwardly spaced outer wall 64. While the contact surface 38 is shown as a vertically outwardly facing surface, the contact surface of the bar 32 may be satisfied with any other inwardly or outwardly directed horizontal, vertical or otherwise oriented surface of the bar 32. I understand that. a pair of side walls 68,
70 extends between outer wall 64 and inner wall 66 and defines a box-shaped groove or passage within conductor bar 32 . Magnetic strips 72, described in more detail below, are located within the grooves or passageways defined by walls 64-70 of conductor bar 32. It has been found to be particularly advantageous to provide the magnetic element 62 within a bar that supplies ground potential.

Still referring to FIG. 3, the contact member 54 includes:
A magnetic sensor indicated at 74 is attached. As shown in FIG. 2, contact member 52 is also provided with a sensor indicated at 76. Two sensors are used to address problems caused by bonding between sections of the magnetic strip, or if either sensor 74, 76 becomes inactive for some reason. Of course, it will be appreciated that a single sensor or more than one sensor may be used. sensor 7
4 and 76 are connected to output wires 78 and 80, respectively. Sensors 74, 76 may be those manufactured by Microswitch, a division of Honeywell, part number SS21PE or SS22PE. Sensors 74, 76 are provided with magnetoresistive material integrated on silicon and protected by an epoxy overcoat. Each sensor includes an integrated circuit that produces a digital output in response to detecting a magnetic field.

Referring to FIG. 4, magnetic strip 72 is magnetized to provide alternating north and south poles providing alternating regions of magnetic flux. Magnetic strip 72 is preferably formed from barium ferrite powder mixed with a synthetic rubber substrate;
It is extruded into a suitable cross section, such as the rectangular cross section shown in FIG. Magnetic strip 72 is then magnetized in a conventional manner to provide a permanent magnetic member with alternating magnetic flux regions.

For purposes of illustration, regions 80, 82 of strip 72
and 84 will be explained. Precise lines of boundaries are provided between regions 80, 82 and 84. Line 86 separates regions 80 and 82 and line 88 separates regions 82 and 84.
Separate. Lines 86, 88 are oriented substantially perpendicular to the direction of movement of vehicle 10 along rail 12. A region with no magnetic flux exists midway between the north and south poles provided in each region 80, 82, and 84.

In an embodiment, the alternating magnetic regions are of constant and equal length. In the original configuration, strip 72 was magnetized such that each magnetized region had a length of 0.125 inches.

A strip 72 having a predetermined number of regions and a predetermined length.
It is possible to vary the length of the magnetic member in the region as long as it is provided for.

Another method is to provide the magnetized strip with N and/or S magnetized regions separated by non-flux regions.

Referring to FIG. 6, the alternating magnetization regions of the magnetized strip 72 extend along the length of the strip 72 as shown just below the strip 72 as shown in FIG. Provide variation. As vehicle 10 moves along rail 12, sensors 74, 76 sense the presence of alternating magnetic flux regions of magnetized strips and output open or closed circuits in response to the presence or absence of a magnetic field. Sensors 74, 76 output either open or closed circuits in response to the presence or absence of a magnetic field. As shown in the lower part of FIG. 6, the sensors 74, 76 output a closed circuit regardless of the north or south pole when the strength of the magnetic field rises above a predetermined threshold. If the magnetic field falls below the threshold, the sensors 74, 76
outputs an open circuit until the predetermined threshold is detected once again. In this manner, a closed circuit is repeatedly output by the sensors 74, 76 as they move along the length of the strip 72 during movement of the vehicle 10 along the rail 12.

FIG. 6 shows the period of the "on" state of the sensors 74, 76 as being longer than the period of the "off" state. The relationship between the period of the "on" state of the sensors 74, 76 with respect to the period of the "off" state is that the magnetic strength of the strip 72, the sensor 74,
76 sensitivity and electronic circuitry.

FIG. 5 shows a control device for the vehicle 10. As shown in FIG. Sensors 74, 76 are connected to microcontroller 90 via wires 78, 80. Microcontroller 90 may be any suitable device such as a microprocessor, programmable controller, or the like. Each of the sensors 74, 76 provides an input signal to the microcontroller 90. As mentioned above, the input signal is in the form of an open circuit or a closed circuit depending on the position of the sensors 74, 76 in relation to the magnetic strip 72. Microcontroller 90 is operative to count the number of open or closed circuits input by sensors 74, 76, and this information is used to calculate the speed, position and/or displacement of vehicle 10 relative to rail 12. .

Microcontroller 90 connects each wire 92
receives an input signal from one of the conductor bars providing a reference input via the conductor bar. The input signal from the conductor bar may be in frequency, voltage, amperage, or a combination thereof as desired. For example, if a predetermined speed of vehicle 10 is desired, microcontroller 90 is programmed such that a predetermined reference signal input to microcontroller 90 from a conductor rail causes vehicle 10 to move at a predetermined speed. Microcontroller 90 processes input signals from sensors 74, 76 to determine the actual speed and distance traveled by vehicle 10. The microcontroller 9 via a satisfactory speed regulating device such as an adjustable frequency drive 92
0 acts to control the speed of the trolley motor, indicated at 94, to achieve the desired predetermined speed by the input reference signal.

The signals output by sensors 74, 76 may be processed by microcontroller 90 according to the well-known right angle principle to determine the direction of movement of vehicle 10 on rail 12.

A modem 96 or other suitable communication device may be used to establish the desired speed set point with microcontroller 90. Modem 96 is connected to electrical equipment 24 via a connection indicated at 98 and to microcontroller 90 via a connection indicated at 100. Communication signals are sent via the conductor bars of the electrical device 24 to the modem 96 and through it to the microcontroller 90 for commands such as speed settings, distance settings, and/or target settings.

Using the device of the invention, the speed of the vehicle 10,
It is possible to provide position and displacement indications at all times. In an automated system with a large number of vehicles, the speed of each vehicle can be constantly varied to maintain a predetermined spacing between the vehicles. In material storage and retrieval equipment, the exact location of each vehicle can be monitored at all times. These are just a few examples of the many applications of this device.

Although particular embodiments of the invention have been described with respect to particular circumstances, it will be understood that various details, as well as particular applications of the invention, may be changed without departing from the spirit or scope of the invention. For example, the magnetized strip may be attached to the rail in any satisfactory manner, such as by adhesive or mechanical means. The magnetic strips may be added to the structural member and need not be attached to the rail. Additionally, although language has been used to indicate that the rails 12 are horizontal and that the vehicle 10 moves merely horizontally, the rails 12 may be oriented vertically, but do not represent vertical movement of the vehicle 10 or upward or downward movement of the vehicle 10. It is understood that there may be a slope that occurs.

Additionally, as previously mentioned, it is possible to vary the length of the alternating magnetic regions provided on the strip 72 as long as a predetermined number of regions are provided for a given length of the strip 72. If the microcontroller 90 simply operates to count the number of open or closed circuits input by the sensors 74, 76, the position and displacement of the vehicle 10 with respect to the rail 12 will be the average velocity of the vehicle 10 or the rail 12. may simply be determined by the absolute number of open and closed circuits input by sensors 74,76. It is advantageous to create alternating magnetic fluxes of constant equal length to provide accurate discrete determination of vehicle speed. This also facilitates the manufacture of the magnetization of the strip 72.

Various modifications and embodiments may be made which particularly point out the subject matter of the invention and which are clearly within the scope of the appended claims.

[Brief explanation of the drawing]

1 is a partial perspective view of a vehicle mounted on electrified rails together with an automated robot carried by the vehicle; FIG.

2 is a partial plan view of a portion of the apparatus of FIG. 1 showing a pickup that supplies power from the rail electrification device to a vehicle motor; FIG.

FIG. 3 is a partial cross-sectional view taken approximately along line 3-3 in FIG. 2;

FIG. 4 is a schematic diagram of alternating magnetic poles provided on the sensor and magnetic strip;

FIG. 5 is a system diagram of an apparatus responsive to sensors to determine one or more operating characteristics of a vehicle associated with a rail.

FIG. 6 is a schematic diagram showing an alternating magnetic field provided in the strip and a magnetic strip measured in a graphical representation of the sensor output.

[Explanation of symbols]

10 Vehicle 12 Rail 14 Lower rail 16, 18, 20, 22, 44 Support member 24 Electrification device 26, 28, 30, 32 Conductor bar 34 Box 36 Pick-up 38 Contact surface 40 Hanger 42 Bracket 46 Arm member 48, 50 Contact holder 52, 54 Contacts 56, 58, 78, 80, 98, 100 Wire 64
Outer wall 66 Inner wall 68, 70 Side wall 72 Magnetic strip 74, 76 Sensor 80, 82, 84 Area 86, 88 Line 90 Microcontroller 92 Frequency drive 94 Trolley motor 96 Modem

Claims (13)

[Claims] Claims: 1. A vehicle for transporting articles; rail means for supporting the vehicle and on which the vehicle is movable; means for moving the vehicle on the rail means; attached to the rail means. magnetizable elongated strips separated by non-flux regions along their length and magnetized to provide permanent regions of magnetic flux oriented non-parallel to the direction of movement of the vehicle on the rail means. a fixed permanent magnetic member; a sensor means mounted on the vehicle and movable and operative to sense a field of magnetic flux provided on the magnetic strip and output a signal in response; means for outputting a signal in response to determining one or more operating characteristics of the vehicle in relation to the rail means. 2. The apparatus of claim 1, wherein the magnetic strip is magnetized to provide regions of alternating magnetic flux separated by regions of non-magnetic flux. 3. The apparatus of claim 2, wherein the alternating magnetic flux regions in the magnetic strip are oriented substantially perpendicular to the direction of travel of the vehicle of the rail means. 4. The apparatus of claim 3, wherein the regions of alternating magnetic flux are of substantially constant equal length along the length of the magnetic strip. 5. The means for moving the vehicle on the rail means comprises an electric motor attached to the vehicle, a power supply conductor bar means attached to the rail means, and a power supply from the power supply means. 2. The apparatus of claim 1, further comprising pickup means for transmitting a control signal to said electric motor, transmitting a control signal to a vehicle controller, and transmitting a ground potential to the vehicle. 6. The power supply conductor bar means comprises a conductor bar attached to the rail means, wherein the magnetic strip is attached to the conductor bar and the sensor means is attached to the pickup. equipment. 7. The apparatus of claim 6, wherein the conductor bar includes an axial path along its length, and wherein the magnetic strip is located within the path. 8. The means responsive to the sensor means receives an output signal from the sensor means and processes the output signal to determine one or more operating characteristics of the vehicle associated with the rail means. 2. The apparatus of claim 1. 9. The means responsive to the sensor means is arranged to operate between the sensor means and the means for moving the vehicle on the rail means and is responsive to the one or more operating characteristics. 9. The apparatus of claim 8 comprising control means for controlling the speed of operation of said vehicle on said rail means in response to the determination. 10. An article moving apparatus comprising a vehicle, rail means for supporting the vehicle and on which the vehicle is movable, and means for moving the vehicle on the rail means, the article being attached to the rail means. a fixed permanent magnetic member consisting of magnetizable elongated strips separated by non-flux regions and magnetized to provide permanent regions of magnetic flux regions oriented non-parallel to the direction of movement of the vehicle on the rail means; attached to the vehicle,
sensor means movable therewith and operative to sense a field of magnetic flux disposed on the magnetic strip and output a signal in response; a sensor means responsive to the sensor means output signal and associated with the rail means; and means for determining one or more operating characteristics of the vehicle with respect to the rail means. 11. An article moving device comprising a vehicle, rail means for supporting the vehicle and on which the vehicle is movable, and means for moving the vehicle on the rail means, the member being permanently magnetizable. permanently magnetizing said magnetizable member to provide permanent areas of magnetic flux along its length separated by non-flux regions; and on said magnetizable member as said vehicle moves over said rail means. a sensor is provided on the vehicle to sense a magnetic flux region of the vehicle and output a signal in response; one or more operating characteristics of the vehicle associated with the rail means are determined from the signal output by the sensor; A method of determining one or more operating characteristics of a vehicle with respect to said rail means, comprising the step of determining. 12. Determining one or more operating characteristics of a first object with respect to a second object, wherein the first and second objects are located adjacent to each other, and one of the objects movable with respect to the other: provided on one of the objects, separated by non-flux regions, to provide a permanent region of magnetic flux along its length, with flux regions oriented non-parallel to the relative direction between the objects. a fixed permanent magnetic member to be magnetized; a sensor means provided on the other side of the object for sensing a magnetic flux region provided on the magnetic member and outputting a signal responsive thereto; and means for determining one or more motion characteristics between an object and a second object. 13. Determining one or more operating characteristics of a first object with respect to a second object, wherein the first and second objects are located adjacent to each other and one of the objects is determined with respect to the other. movable: providing a permanently magnetizable member; permanently magnetizing the magnetizable member to provide a permanent region of magnetic flux along its length separated by a non-flux region; providing said magnetizable member on one of the objects such that it is oriented non-parallel to the direction of movement between the two objects; providing a sensor on the other of the objects that senses a region of magnetic flux that is oriented non-parallel to the direction of movement between the two objects; A sensor is provided on the other side of the object for sensing the magnetic flux region of the member that can be formed and outputting a signal in response, and from the signal output by the sensor means,
A method for determining a motion characteristic comprising determining one or more motion characteristics between a first object and a second object.