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Publication numberUS3840736 A
Publication typeGrant
Publication dateOct 8, 1974
Filing dateOct 27, 1972
Priority dateOct 27, 1971
Publication numberUS 3840736 A, US 3840736A, US-A-3840736, US3840736 A, US3840736A
InventorsAsano T, Morimoto Y, Takamiya H
Original AssigneeMitsubishi Electric Corp
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Apparatus for controlling vehicles at junction points
US 3840736 A
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Description  (OCR text may contain errors)

limited States Patent Asano et a1. Oct. 8, 1974 APPARATUS FOR CONTROLLING VEHICLES AT JUNCTION POINTS [56] References Cited [75] Inventors: Tetsumasa Asano; Hiroshi UNITED STATES PATENTS Takamiya; Yflshinflbu Morimoto, 3,078,944 2/1963 Gray 246/63 R of Himeji, Japan 3,263,625 8/1966 Midis et a1. 104/148 R 73 Assignee: Mitsubishi Denki Kabushiki Kaisha, 212" "y /mg:

y Japan y [22] Filed: Oct. 27, 1972 Primary Examiner-M. Henson Wood, Jr.

Assistant Examiner-George I-I. Libman [21] p 301489 Attorney, Agent, or FirmOblon, Fisher, Spivak,

McClelland & Maier [30] Foreign Application Priority Data Oct. 27, 1971 Japan 46-85287 [57] ABSTRACT Oct. 28, 1971 Japan 46-85862 An apparatus is disclosed for controlling Separate or a Oct. 28, 1971 Japan..... I 46-85863 few interconnected vehicles running along a track Oct. 29. 1971 Japan 46-86131 Such as Separate rail cars, or types of similar vehicles. The system permits both high vehicle speeds and high [52] 246/63 104/ 246/167 traffic densities, and is especially effective for control- 1 Int ling the distance between vehicles at a junction or t thy d i t Field of Search 246/187 B, 187 c, 167 R, Swltchmg pOmt a rack pa or ma way wot 246/63 R, 63 A, 63 C; 104/148 R, 149, 152' 7 Claims, 6 Drawing Figures APPARATUS FOR CONTROLLING-VEHICLES AT JUNCTION POINTS BACKGROUND OF THE INVENTION '1 Field of the Invention:

This invention relates generally to an apparatus for controlling vehicles, and more particularly to an apparatus for controlling the spacing and speed of vehicles at a junction point in a track, path or roadway network.

enlarged, making it difficult to permit both high vehicle speeds and high traffic densities at the divergence point.

In order to overcome the difficulty, it is possible to separate the systems controlling traffic on the main line and on the branch line for a specific distance on either side of the diverging or junction point, so as to provide vehicle control depending upon the vehicles position with respect to either the main line or the branch line. However, a complicated apparatus is required for such control.

As stated above, if the radius of curvature of the branch line is increased, the space between the main line and the branch line is less than the width of the vehicles along a considerable distance which defines an area of interference. If the distance between a forward vehicle and a following vehicle is sufficient, no interference occurs. However, at high vehicle speeds and traffic densities, a long area of interference is considered dangerous because of the short distance between vehicles and the high running speed. Accordingly, it is necessary that vehicles passing on one line receive a warning or information signal from vehicles passing on the other line in the interference area.

Moreover, in addition to the problem created by two vehicles approaching two branch lines from the main line, it is also necessary to consider the problem of interference between a plurality of vehicles running from two branch lines onto a main line. l-Ieretofore, in order to control such situations, vehicles on two lines have been alternatively stopped and then permitted to enter the main line, so as to pass without interference. The

running interval ratio in such situations has been regulated depending upon the crowdedness of each line.

SUMMARY OF THE INVENTION Accordingly, one object of the invention is to provide a novel apparatus for controlling individual vehicles,

that they take the most direct route to any selected des- I tination."

Another object of this invention is to direct vehicles along the shortest route to any selected destination, taking into consideration the congested nature of traffic along the route.

BRIEF DESCRIPTION OF THE DRAWINGS A more complete appreciation of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:

FIG. 1 is a schematic diagram showing basic circuit configurations used with the present invention;

FIG. 2 is a schematic diagram of one embodiment of the apparatus for controlling vehicles according to this invention;

FIG. 3 and 4 are, respectively, schematic diagrams of other embodiments according to the present invention;

ment of the present invention illustrating a system for switching vehicles among branch lines.

DESCRIPTION OF THE PREFERRE EMBODIMENTS Referring now to the drawings, wherein like reference numerals generally designate identical or corresponding parts throughout the several views, and especially to FIGS. 1 and 2, one embodiment of the apparatus of this invention for controlling vehicles is shown, wherein the reference numeral 1 designates a car or an electrically powered vehicle, 2 designates a driving means or motor for the car 1, 3 designates a damping or braking means for the car 1, 4 designates a speed dynamo or tachometer generator and 5 designates an amplifier. Similarly, 6 designates a receiving element fitted on the front surface of car so as to progressively contact the below described conductive segments. The numeral 7 designates a car element, such as a car piece fitted to the back surface of the car, for progressively contacting the ground elements described below. The numeral 9 designates current collectors connected to feeder or power lines 8, and 10 designates a constant voltage line carrying a reference voltage V,.

The references A A A A A B,. AB AC AD AD AE,, AE, designate, respectively, ground elements, which may be magnetic proximity switches, for example. The references BA,, BA BB BB BC BC BD BD BE,, BE designate, respectively, conductive segments which have impressed on them the output'voltage of the below described addition devices. The conductive segments are insulated from each other and are positioned along the line of the track, path or roadway. The reference D,, D,, designate addition devices, while E,, E, designate gates for switching the output signals of the addition devices after receiving signals from the ground elements, and F,, F, designate addition resistances progressively having the output of constant voltage line 10 impressed upon them. The references G,, G designate respectively addition resistances for progressively feeding the output of each of the addition devices to the next addition device. The references CA,, CA,,, CB, CB CC, CC ,CD,, CD .designate respectively output voltage controlling devices, each of which is comprised of an addition device, a gate for switching the output of the addition device, an addition resistance and the output of the constant voltage generator.

The references CE, CE, designate respectively auxiliary output voltage controlling devices which include components similar to these of output voltage controlling devices CC, CC;, or CD, CD Although for the sake of simplicity the blocks containing the output voltage controlling devices and the auxiliary output voltage controlling devices are shown as being interconnected by a single line, it is to be understood that in fact the respective addition circuits, gate circuits and constant voltage generator outputs contained in each block are individually interconnected as in, for example, FIG. 4. The final stage output of the output voltage controlling device CE, is connected so as to be the input of the output voltage controlling device C8,. The track including the conductive segments BA,, BA is called a main line, and the tracks connected to the main line are called a branch lines. The area of interference between two branch lines is called as an interference area or section and the remaining area is called the normal area or section. The conductive segments BB and BB, and also 83;, and B8, are respectively electrically connected.

The operation of the apparatus illustrated in FIG. 1 will now be described. As shown in FIG. 1, through the receiving element 6, the car receives the voltage impressed on the conductive segment B by the illustrated circuitry, which is described in greater detail in copending applications Ser No. 292,104 and Ser. No. 291,621, incorporated herein by reference. This voltage corresponds to the difference between. the car 1 and a lead or forward car (not shown). The voltage is passed through the amplifier to the driving means or motor 2 to drive the car. The driving means 2 and the damping or braking means 3 are operated under the control of a feed-back network to return the output voltage of the speed dynamo or tachometer generator 4 to the input stage of the amplifier 5, whereby the car 1 is run at the speed corresponding to the voltage on the conductive segment BE,,.

The voltages impressed on the conductive segments BE,, BE,, are the outputs of the addition devices D,, D,, which are produced by progressively integrating the signal on the constant voltage line 10, depending upon the distance between cars. For example, the output of the addition device D,, and the constant voltage signal are respectively added through the addition resistances G,, and F,, to the addition device D,, When the output of the addition device D,, is impressed on the conductive segment BE,, it becomes the input ofthe next addition device. The car element 7 faces closely the ground element AE,,, as the car moves and the signal received by the ground element AE,, is coupled to the switching gate E,,, whereby the output of the addition device D,, is made zero. Simultaneously, the addition device D,, is actuated by the switching gate E,, whereby output voltages corresponding to the distance between one car and the following car are generated in the addition devices placed along the track, behind the addition device D,,

More particularly, when the car element 7 of FIG. 1 faces the ground element AE,, the switching gate E,, is set and the other switching gates are reset. The output of the addition device D,, is zero and the input of the addition device D,, (not shown in the drawing) is Vs. The input of the addition device D,, (not shown in the drawing) is the sum of the reference voltage Vs and the output of the addition device D,, which is Vs, because of the reset condition of the switching gate E,, The output of the addition device D,, is thus 2 Vs. Similarly, the voltage nVs is impressed on the conductive segment BE, at a position n elements away from the ground element A15, facing the car element 7. The car 1 receives the voltage of the conductive segment BE, through the brush 6, and the motor is controlled by the damping means 3 which compares the output of the car speed detector 4 with the voltage of the conductive segment to control the speed of the car.

As shown in FIG. 2, in the interference area beyond the diverging point, the ground elements of two lines are respectively laid along the tracks. The output voltage controlling devices CB, C8; are common to the two lines, and provide identical control signals.

Aspecific distance into the normal area from the interference area, the outputs of the ground elements AC, AC are connected so as to simultaneously apply a signal to the output voltage controlling devices CC, CC, and to the auxiliary output voltage controlling devices CE, CE; corresponding to the location of a vehicle at ground elements AC. The outputs of the ground elements AD, AD, are similarly connected so as to simultaneously apply their outputs to the output voltage controlling devices CD, CD and the auxiliary output voltage controlling devices CE, CB corresponding to the location of a vehicle at the ground elements AD When a first car passes the ground element AC, and a second car passes the ground element AD,, the output voltage controlling devices CC, and the auxiliary output voltage controlling device CE, are operated, in response to the first car, and their outputs are transferred progressively through the interconnected devices to the output voltage controlling device CC, and the auxiliary output voltage controlling device CE, in accordance with the operation of the addition networks and gate circuits in each of the controlling devices CC;,, CC, and CC, and the auxiliary output voltage controlling devices CB CB and CE,. On the other hand, the signal transmitted to the auxiliary output voltage controlling device CE,, due to the output signal of the ground element AD, in response to the second car is converted to information concerning the position of the approaching second car by resetting the information transmitted by the output signal of the ground element AC, and instead transmitting a signal indicating the operation of the ground element AD 1 to the output voltage controlling devices beyond the including the device CB In this embodiment, the voltage corresponding to the distance between a particular car and a forward or lead car is impressed on the conductive segments. It is possible to convert the spacing information to car speed information by differentiating the signal corresponding to the car spacing.

In this embodiment, car spacing information is automatically provided from the car nearest to the diverging or junction point by the auxiliary. controlling devices laid along a portion of the branch line, and this information is transmitted to the car running on the main line. There is no need fora car spacing information switching device which distinguishes the direction of the car running on the main line, according to the present invention, and accordingly an economical and accurate control of traffic can be attained using the above described system.

Referring again to the embodiment of the invention illustrated in FIG. 2, a decrease in the speed of a car which will be turned onto the branch line should be provided, which will cause the speed of this car to be different from the speed of following cars which do not turn onto the branch line. In addition the car should be accelerated after it passes the junction point. However the operation of the cars must be carefully regulated to secure safety, for the following reasons, If the car slowing for the turn to the branch line is not closely followed by another car, no hazard'occurs. However, if the turning car is being closely followed by another car which does not reduce its speed, a collision can occur.

In this case, it is necessary to obtain information as to the spacing between a particular car and the forward or leading car. However, in accordance with the above described embodiment of the invention, the car heading for the branch line is automatically controlled depending upon the distnace to the nearest car on the other branch line and the car following that car is also controlled. Accordingly, accidients of the type mentioned will be prevented with the present invention.

Another embodiment of the apparatus of the invention is illustrated in FIG. 3, wherein the reference numeral ll designates a main line; and the car 1 is run from the main line 11 through the junction point to a first branch line 12 or a second branch line 13. The reference numeral 14 designates a main line section and 15 designates an interference area or section, while 16 designates a specific branch section wherein no interference is caused, but the. spacing of the cars in the interference section and the main line section are affected by cars in this section.

In FIG. 3, the reference H designatesa series of ground devices which are essentially the same as the output voltage controlling devices CAn, etc., shown in FIG. 2, and A designates ground elements in the main line section 14, the interference section 15 and the branch line section 16. The reference B designates conductive segments in the main line and the interfering line, and H,,, H,, designate respectively ground devices in the first and the second branch sections 12 and 13, and A A designate respectively ground elements in the first and the second branch sections, while B 8, designate respectively the conductive segments in the first and the second branch sections.

In the embodiment shown in FIG; 3, wherein the ground devices H operating in essentially the same manner as the output voltage controlling devices of FIG. 2 are arranged, when the forward car is in the interference section on either the first or the second branch lines, information concerning the position of the forward car is transmitted to the ground devices I-I through the ground elements A which are connected in parallel. The same signal is transmitted to the conductive segments B of the first and second branch lines, whereby the same car spacing control is provided 6 on both the main line section tion.

Even when the forward car is out of the interference section,if the forward car affects following cars beyond the interference section, the information as to the position of the. forward car is transmitted to the following car by the ground elements A and the ground devices I-I arranged along the first and the second branch lines. The following car travels through the junction point at a speed depending upon the position of the forward car. Thus, for example, a car in the branch section 16 informs following cars of its position through the and the interference secground device H and the following car receives this information through the ground devices H,,, H The following car can thus diverge without interfering with the forward car at the point of divergence.

As stated above, especially in the embodiment of a traffic control system having short car spacing and vehicles running at high speeds and at high traffic densities, the vehicle spacing in the interference section and the main line are controlled so as to prevent interference at the diverging point, by dividing theinterfering section to a plurality of segments. In the interference section, the same vehicle spacing is maintained as on the main line, and no accumulation of vehicles in front of the diverging or junction point occurs, whereby high speed and high traffic density operation can be maintained.

Another embodiment of the invention is illustrated in 5 FIG. 4, wherein the reference numeral 17 designates an arrow indicating the direction of the car 1, and the references AA, AA AB, AC,, AC and AD,, AD, designate respectively ground elements, such as magnetic proximity switches, placed at specificintervals along the track, and the references EA,, EA,,, BC,, BC,, and ED, ED designate respectively gates, for switching the output of the below-described addition devices under the control of the outputs of the ground elements. Similarly, the references DA,, DA DC,, DC and DD, DD respectively represent addition devices generating outputs corresponding to the distance from a forward or lead car, and BA,, BA,,, BB, BB BC,, 8C BD,, BD designate respectively individually insulated conductive segments having impressed thereon the output voltages of the addition devices and arranged along the track line.

The references GA,, GA,,, oc,, GC, and 0D,,

GD designate respectively addition resistances for providing inputs to the addition devices from the constant voltage line 10, and FA,, FA FC, FC FD, FD designate respectively addition resistances providing inputs to the addition devices from the outputs of preceding addition devices. The reference numeral 18 designates a comparision device for comparing the outputs of the addition devices DC, and DD, and for developing a signal from the smaller of these two outputs The operation of the system illustrated in FIG. 4 will now be described in detail. The car receives through the receiving element 6, the voltage on the conductive segment BA,,, which is proportional to the distance from the forward car, and this voltage is transmitted through the amplifier 5 to the driving means 2 to control the car speed, as previously described. The outputs of the addiage line are respectively transmitted through the addition resistances FC GC to the addition device DC and are added at that device. The output of the addition device DC is impressed on the conductive segment BC as a voltage corresponding to car spacing.

As shown in FIG. 4, the conductive segments in the interference section BB and BB BB and BB BB, and BB, are respectively electrically connected to carry the same voltage. In the gates for switching the outputs of the addition devices, for example, when the car element 7 faces the ground element AC the switching gate EC,, is closed, whereby the output of the addition device DC;, is made zero, and the switching gate EC is opened to actuate the addition device following DC An output voltage proportional to car spacing is impressed onto the conductive segment following the conductive segment BC,. When one car faces the ground element AC and another car faces the ground element AD the output voltage of the addition device DC is smaller than the output voltage of the addition device DD,. When the outputs of both devices are compared by the comparison device 18, the smaller output of the addition device DC is impressed on the next addition device DA,,. This signal is progressively transmitted whereby the car 1 runs according to a voltage determined by the distance from the forward car which faces the ground element AC In this embodiment, a voltage corresponding to the car spacing or distance from the forward car, is used. However, it is also possible to calculate the forward car speed from the car spacing information by differentiating the signal corresponding to the car spacing that is provided at the output of the addition device.

As stated above, in this embodiment, in order to properly control traffic at the divergence point using a simple apparatus, the main line and the interfering section of the branch lines are controlled by the same devices to prevent interference between two cars. In normal, non-interfering sections beyond the interfering sections, independent control is provided for each branch line. Accordingly, when a forward car is stopped at a point beyond the interfering section, following cars travelling on other branch lines can run without being affected by the stopped forward car. The control signal between the main line and the interfering branch line is a relatively small signal. If a larger signal is provided, the forward car in the normal section of the first branch line is stopped and the forward car in the normal section of the second branch line approaches from a distant position, and a signal is transmitted corresponding to the distance from the forward car in the second branch line. Accordingly, if the following car gets into the interfering section of the first branch line and the forward car is stopped in the normal section of the first branch line, the following car will collide with the forward car when it reaches the normal section of the first branch line. In order to prevent such accidents, the smaller of the signals from the normal section of the first branch line and the second branch line is transmitted to the interfering section. When the forward car in the normal section of the first branch line is stopped and the forward car in the second branch line approaches from a distant position, the smaller signal of the forward car in the first branch line is transmitted to the interfering section.

If the following car is on the first branch line, there is no problem because a normal car spacing is maintained. However, when the following car is on the interfering section of the second branch line, it runs at a speed corresponding to the distance from the forward car on the first branch line, and accordingly the car suddenly speeds up at the entrance of the normal section of the second branch line. The following car runs at a relatively low speed corresponding the distance from the nearer forward car, and accordingly, even though the car enters the second branch line, the car is under the control of the high traffic density control system, and does not slow down.

On the other hand, after passing the interfering section, it is possible to pass the forward car on the first branch line. In so doing, the speed of the passing car is decreased depending upon the position of the forward car on the same line, and after passing the forward car in the other line, the speed is increased. When the car enters the second branch line at a high speed with no forward or lead car, the following car is safe. However, when the following car enters the other line wherein there is a forward car, a collision with the forward car on the line is possible. Such accidents are caused by running the following carat the same speed as the forward car. Thus, it is necessary to obtain information as to the distance to a slowly moving or stopped forward car on different brances of the line. However, in accordance with the present embodiment of the invention, even cars on branch lines having no forward cars are automatically damped if a slowly moving or stopped forward car is detected on a different branch line, and the following car is also slowed correspondingly, so that no accident happens.

Another embodiment of the invention is illustrated in FIG. 5 wherein cars are run from two branch lines onto one main line, the opposite of the former embodiment. The cars are automatically and efficiently run from branch lines to one main line in the order of their arrival at the junction.

In FIG. 5, the references AA,, AB, designate respectively ground elements, such as magnetic proximity switches, which are arranged at specific intervals along a track, and are progressively faced by the car element 7. The references EA, EB, designate respectively gates for switching outputs of addition devices upon receiving signals generated by the progressively triggered ground elements as the car passes, and DA, DB designate respectively addition devices summing progressively the output of the constant voltage generator to develop a signal corresponding to the dis tance between a following car and a forward car. The references FA, PB designate respectively addition resistances coupling the outputs of the addition devices DA DB to inputs of the next respective addition devices, and GA, G8,, designate respectively addition resistances coupling the signal on the constant voltage line 10 to the input of the addition devices DD, DB The references BA, BB designate respectively conductive segments on which the output voltages of the addition devices DA,, DB are impressed, and which are insulated from each other and are arranged along the track line. The references K K 3 designate respectively speed decreasing signal devices for generating decreasing output voltages in a predetermined section of two tracks near a junction point, while CA CA designate respectively output voltage controlling devices for passing smaller output signals after measuring the outputs of the addition devices DA,, DA,, The references CB, CB designate respectively output voltage controlling devices for passing smaller outputs after comparing the outputs of the addition devices DB,, DB,, and which close the outputs of the addition device DA,, DA when impressing the output of the below described zero detectors, and pass the smaller of the output of the addition devices DB,, DB,, or the output of the speed decreasing signal devices K, K,,. The references J, J designate respectively zero detectors for supplying an o'utput signal indicating the detection of a zero to the output voltage controlling devices CB, CB when the voltages on the conductive segments of two tracks are zero by comparing the voltage on the conductive segments BA,, and BB,,

The operation of the embodiment illustrated in FIG. will now be described in detail. When the car element 7 faces the ground element AA,, the signal received by the ground element is transmitted to the switch controlling gate EA,, whereby the output of the addition device DA is made zeroand is simultaneously transmitted to the switch controlling gate EA,, whereby the output of the addition gate is cut off. The addition device DA,, which has an input from the constant voltage generator coupled through the addition resistance GA,, generates an output which is impressed on the conductive segments BA,,., and BB and is provided as the input of the addition device DAM, Similarly, when the car element 7 faces the ground element AA as the car 1 moves, the signalreceived by the ground element AA,, is transmitted to the switch controlling gate EA,, whereby the output of the addition device DA,, is made zero, and an output is simultaneously generated by the addition device DA,, The output of the addition device is increased by specific voltage increments depending upon the progress of the car, and corresponds to the spacing between cars.

The track section including the conductive segments BA,, BA BA and BB, BB, is the junction section or interference section. In order to prevent collisions, the pairs of conductive segments BA and BB,, and BA, are electrically connected to control the two lines at the interference section with.

one control system. The interference section is usually more than 30 meters in length, for example. The sec-. tion including the conductive segments BA,,

BA,, and BB,,,, BB,, is the junction controlling section in front of the interference section, and is an important track section for attaining the desired effect of this invention. The junction controlling section is usually about 100 meters in length in a railway system.

vices DB,, DB,, on the other line and the output of the decreasing signal devices.

On the other hand, the voltages impressed on the conductive segments BB,, BB,, are controlled by the output voltage controlling devices CB, CB so as to impress the higher of l the output voltage of the 65 addition devices DA,, DA,,,., on the car line or (2) the smaller of the output voltage of the addition devices DA,, DA,, on the other line and the outputvoltage of the decreasing signal devices.

When two cars are running in parallel on each line at corresponding positions in the junction controlling sec- 5 tion, the following control'arrangement is provided to allow the car on the conductive segments BA,, BA to pass first. First, it is pointed out that when two cars are running on each line in parallel, the car element of each car simultaneously faces the ground elements on each line. The resulting signal from the ground element is passed through the switch control gate whereby the output of the addition devices DA,,., and DB,, DA,, and DB are simultaneously reduced to zero and the impressed voltages of the conductive segments BA,,., and BB BA, and B8,, carrying the above outputs are also zero. This condition is detected by the zero detectors J, J When the voltages impressed on corresponding conductive segments are simultaneously zero, the outputs of the zero detectors J, J, are applied to the output voltage control de vices CB, CB whereby the output voltage control devices CB, CB cut off the outputs of the addition devices DA,, DB,, on the other line to prevent these outputs from being supplied to the output voltage control devices CB, CB Accordingly, the system operates so as to impress only the smaller of (l) the output voltage of the addition devices DB,, DE on the car line or (2) the output voltage of the decreasing signal devices K, K on the conductive segments BB,, BB,, The operation of this embodiment of the invention will now be further described in terms of several exemplary operating situations.

EXAMPLE 1 Running on Independent Lines When cars runs on the main line before reaching the junction controlling section, or after passing the divergence point, the output of the addition device at the position of the forward car, is zero, and the voltage on the constant voltage line is progressively integrated at areas behind the position of the forward car, whereby an output proportional to the distance from the forward car is provided at the position of the following car. The. following car then runs at an appropriate speed for preventing a collision with the forward car.

EXAMPLE 2 Running in theJunction Controlling Section (2-1 Control equation v The voltage provided to each conductive segment in the junction controlling section can be expressed in equation form. The appropriate voltage value can be calculated from the outputs of the voltage controlling devices CBi, CAi and the zero detector Ji. Thus:

E Ai min. [V Ai, max (V Gi, V Bi) (normal Condition)] (1) 60 E Bi min. [V Bi, max (V Gi, V Ai) (different distances from the junction)] 2 wherein:

E Ai is the voltage impressed ment F Ai;

on the conductive seg-- E Bi is the voltage impressed on the conductive segment F Bi;

V Al is the output voltage of the addition device C V Bi is the output voltage of the addition device C Bi;

and

V Gi is the output voltage of the speed decreasing signal device.

In FIG. 5, three conductive segments are shown where i= 1, 2, 3. However about 100 circuit segments are joined to form the junction controlling section. It is further noted that the term same distance from the junction in the Equation (3) means a situation in which two cars run on different branch lines but at the same distance from the junction point. The term different distances from the junction in the equation (2) means a situation in which two cars run on different branch lines at significantly different distances from the junction point. (2-2) Single Car In the Junction Controlling Section When one car runs into the junction controlling section from one branch line, as in the case when there is no forward car in the section, the movement of the car is as follows:

V Ai V Bi V Bi E Ai E Bi V Ai V Bi Accordingly, the car runs as if a car running on the main line is considered as the forward car.

(2-3) Plurality of Cars Running on One Branch Line When a plurality of cars run on only one branch line, the first car runs as the above described single car and, the next car runs keeping an appropriate distance behind the forward car. For example, when no car runs on line B (the lower branch in the FIGURE) and a plurality of cars run on line A (the upper branch in the FIGURE) the output voltages are as follows:

* E Ai V Ai The output voltage, proportional to the distance from the forward car on A line, is impressed on the conductive segment B Ai.

(2-4) Car Running on Both of the Branch Lines At Different Distances From the Junction When one or more cars run on lineA, and another car enters line B, the output voltages are as follows:

* E Bi max (V Gi, V Ai). In the case where V Ai V Gi, the impressed voltage equation is E Bi V Gi, and the car on line B stops at the end of the junction controlling section. However, when the car on line A runs, the output voltage will be V Ai V Gi, and thereafter the impressed voltage is E Bi V Ai, and the car runs at a speed corresponding to the distance from the caron the other line. When many cars runon line A at slow speed, and the car first reaching the junction controlling section is on line B, the car on line B passes ahead of the cars on line A. The technique of preventing interfcrence at the junction is described below.

(2-5) Cars Running on Both ofthe Branch Lines At the Same Distances From the Junction When cars reach the junction controlling section at the same time on both lines, the car on line A has priority, and the speed of the car on line B is decreased because the output voltage controlling line B is limited to the output voltage V Gi of the speed decreasing signal device Gi.

EXAMPLE 3 Evidence of No Interference In order to understand how the present invention eliminates traffic interference, the following example is presented. Consider first the following equation:

E Ai E Bi min (V Ai, V Bi) The cars on each line are controlled to run at a speed which depends upon the position and speed of the nearest forward car running on either the same or a different line. One of the cars running in parallel is slowed down, so as to put the cars into the relationship of a forward car and a following car, even though they are on the different lines. Accordingly, any interference at the junction is prevented.

However, in this control system, if two cars enter the junction controlling section at high speed and separated by only a small distance, the following car, even though on a different line, is suddenly affected by the forward car on the other line, and a severe decrease in its speed may occur. In order to prevent this difficulty, when a forward car is present on another line, the signal for decreasing speed is provided by the speed decreasing signal device K,. The output voltage V Gi can be a small value near the junction, and accordingly the following equation obtains:

E Ai E Bi min. (V Ai, V Bi). As stated above, the

running voltage impressed on each conductive segment depends upon the distance from the forward car on each of the branch lines to allow cars to move from the branch lines onto the main line. Accordingly, as shown in FIG. 5, the receiving element 6 of the car 1 contacts the conductive segment BA so as to receive the voltage impressed thereon. This voltage is passed through the amplifier 5 to the driving means 2 to control the car. vA feed-back control system for feeding back the output voltage of the speed dynamo 4 to the amplifier is provided whereby the damping or braking means 3 is actuated to control the driving means or motor 2 so as to regulate the car speed corresponding to the voltage impressed on the conductive segments.

In the above described embodiment, the voltage on the conductive segments corresponds to the car spacing. However, it is also possible to develop a signal proportional to'the speed of the forward car, and to the car spacing and to impress this signal on the conductive segments. Furthermore, the system described above includes a network for progressively integrating the signal on the constant voltage line 10, to provide inputs to the addition devices DA and DB", as a form of car spacing signal. It is alternatively possible to employ a digital system for detecting the car spacing using counters, the outputs of which correspond to the car spacing.

As is clear from the above disclosure, in this embodiment, the car speed instruction from one line, the car speed instruction from the other line and the speed decreasing information, are compared. The lowest car speed instruction is then used as the control signal. Otherwise, the higher of the car speed instruction from the line not carrying the car or the speed decreasing information is used as the control signal.

Referring now to the embodiment illustrated in FIG.

. 6, an information transmission system is disclosed for vehicles such as cars, each of which have respectively different destinations and carry cargoes or passengers to such different destinations. This novel control system allows the vehicles to arrive at their respective destinations as soon as possible, by electing the most efficient direction of travel. However in general, in order to change the distination of a vehicle running on a track using a ground switch system, the vehicle is allowed to approach a junction point only after the completion of the switching operation is confirmed for purposes of safety. If the switching is not completed, it is necessary for the vehicle to wait at the junction point. Accordingly, at the initiation of switching, it is necessary to maintain the vehicle at a position sufficiently far from the junction to permit it to stop if necessary. The initiation of switching may be carried out after the passing of a forward vehicle, accordingly, it is also necessary to keep the vehicle spacing longer than the stopping distance of the vehicle.

There is no problem is employing ground switching in conventional train controls to regulate car spacing. However, the present embodiment provides the possibility of increasing total traffic volume .by controlling high traffic densities and transferring the vehicles to the shortest course. In this system, the speed of following vehicles is dependent upon the speed of forward or leading vehicles and vehicle spacing. Accordingly, the vehicle spacing is quite small when both vehicles run at the same speed, and only an excess safety distance corresponding to a difference in stopping distances is maintained. However, it is not allowable for vehicles having alternatively different distinations to use conventional ground switching systems. therefore, it is necessary to allow the vehicles having the same distination to occasionally enter junctions points for switching to other lines. Accordingly, each vehicle arrives through a roundabout route at its destination, which is inefficient and causes a decrease in total traffic volume. In order to overcome this difficulty, in the embodiment of FIG. 6 a device for controlling car switching is fitted to each vehicle, whereby each vehicle finishes the necessary preparation for switching before entering a divergence or junction point. However, it is necessary to transmit each switching instruction through certain ground devices, and there are various difficulties in the information transmission between a large number of vehicles and the ground devices. These difficulties can be overcome by providing a series transmission circuit along the tracks for transmitting information as to the forward vehicle speed and information as to the vehicle spacing and also providing parallel transmission circuits for transmitting the switching instructions between the vehicles and the ground controlling devices, which are placed-predetermined distances apart along the tracks. I

The embodiment illustrating these features isshown in FIG. 6, wherein the reference numeral 19 designates a speed controlling device for controlling a driving means or motor 20 in the vehicle I, which is operated by DC current provided through the receiving element 6. The numeral 21 designatesa device for transmitting and receiving signals between a ground controlling device and the means which is connected through a DC blocking condenser 22 to the receiving element 6. Similarly, 23 designates a device for controlling divergence or switching which is controlled by the output of the means for transmitting andreceiving signals. The divergence controlling device causes selective connection of guide wheels to a groove in the track for straight running or a groove in the track for diverging, i.e., switching to another-track. The reference numeral 24 designates distance detectors which are connected to each other by a series transmission line, and which provides a signal indicating the distance from a forward vehicle, that is, an output corresponding to the number of ground elements AE,, and, thus the number of conductive segments BE between a particular car and the forward car. When the ground elements AE, faces the element 7 of the vehicle and detects the presence of the vehicle, the ground element generates a signal indicating the presence of the vehicle until the forward ground element AE detects the vehicle.

The reference numeral 26, designates a blocking condenser while 27 designates a ground resistance and 28 designates'a parallel transmission line for transmitting a direction-information signal having a first fre- 'quency F generated by the means 21. The parallel transmission line transmits a switching instruction information signal having the second frequency F from the ground controlling device 29 to the means 21. The

speed controlling device'19 determines the speed of the vehicle as a-function of both of the vehicle spacing and the relative speed of two vehicles measured by differentiating the output signal of the spacing detector 24 whereby the driving means 20 is properly driven. In this embodiment, the ground element AE,, facing the element 7 of the forward vehicle (not shown in the drawing) generates a signal indicating the presence of the vehicle, until the element 7 faces the next ground element AE whereby the integrated output of the unit or reference voltage generated by the spacing detector 24, is impressed on the receiving element 6 of the following vehicle 1 as the forward vehicle moves. The unit voltage is proportional to the length of the conductive segment BE, and the integrated value is proportional to the spacing between thetwo vehicles. Accordingly, the relative speed of the two vehicles determined by the input voltageof the receiving element 6 changes. The differentiated value of this input voltage is proportional to the relative speed of the vehicles. The speed of the forward vehicle can be measured by adding to the relative speed the speed of the following vehicle which can be detected by a speed dynamo or tachometer generator which is not shown in the drawing.

High traffic densities and safe operation are thus attained by driving the vehicle 1 depending upon the speed of the forwardvehicle and the spacing between the two vehicles.

At a position sufficiently far from a diverging or junction point, a specific codenumber, or destination station code number, for each vehicle is transmitted from the means 21 to the ground controlling device 29. This information is preferably transmitted in code at a first frequency F The transmitted information is passed through the DC blocking condenser 22, the receiving element 6, the conductive element BE, and the parallel transmission line 28. More than two vehicles are not allowed on any one conductive segment BE, at the same time. Accordingly, the ground controlling device 29 may receive signals having the same frequency from a plurality of vehicles without confusion.

When the destination information is transmitted to the ground controlling device 29, the device 29 selects the course having the shortest time and the shortest distance to the desired destination, taking into account.

traffic congestion on the tracks. The device 29 then decides the divergence or switching of the vehicle at the various diverging or junction points, and transmits this information to the vehicle. This information indicating the proper direction of the vehicle, may be in the form of a specific code transmitted at a second frequency F Although many vehicles may receive this signal at the same time, each vehicles selects only infromation corresponding to its own specific code number, and the switch actuating device 23 is triggered. The result of this operation is transmitted back to the ground controlling device 29 and the vehicle is permitted to run through the junction point orswitch.

It is noted that several spacing detector units 24 and frequency separating filters 30 may be packed inv one control box.

To summarize, in the present invention the vehicle spacing information is utilized for obtaining the speed of a forward vehicle. As stated above, in accordance with the invention, high traffic density operation is attained and the minimum safe spacing between vehicles is shortened by providing a transmission line for transmitting vehicle spacing information and vehicle speed information between vehicles. In addition, switching instructions are transmitted by providing a transmission line between the ground controlling device and the vehicles, thereby switching each vehicle independently.-

Moreover, the present invention insures that all vehicles traveling to each destination take the shortest course without using a roundabout route, and when the shortest course is congested, the vehicles take the shortest uncongested route, so as to attain efficient traffic control depending upon the traffic conditions at each moment.

As stated above, in accordance with the apparatus of this invention, optimum control of vehicles running on a track can be attained. Control of the vehicles running on a main line can also be attained with both high vehicle speeds and high traffic densities, whereby the vehicles can run safely and accurately with high efficiency and without danger of collision.

More detailed information as to the operation and structure of the various specific circuit elements described hereinabove will be found in the two applications referenced previously.

Obviously, numerous additional modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein.

What is claimed as new and desired to be secured by Letters Patent of the United States is:

1. An apparatus for controlling a vehicle comprising:

a first plurality of ground elements placed at predetermined intervals along a main line,

a second plurality of ground elements placed at predetermined intervals along a first branch of said main line,

a third plurality of ground elements placed at predetermined intervals along a second branch of said 16 main line,

all of said ground elements generating output signals as said vehicle passes said ground elements,

a plurality of adding devices coupled to said ground elements for progressively summing said output signals and for generating output signals indicating said progressive summing.

control means responsive to said progressive summing output signals for regulating the speed of said vehicle and the spacing between said vehicle and other vehicles,

auxiliary control means responsive only to output signals generated by said second and third pluralities of ground elements; and,

circuit means responsive to said auxiliary control means for controlling said vehicle in a zone where said first and second branch lines merge with said main line.

2. An apparatus for controlling a vehicle as in claim 1 further comprising:

a plurality of conductive segments arranged along said main line and said first and second branch lines and connected to said ground elements.

3. An apparatus for controlling a vehicle as in claim 2, further comprising:

a receiving element coupled to said vehicle for progressively contacting said conductive segments; and

driving means coupled to said receiving element for driving said vehicle in response to output signals from said receiving element.

4. An apparatus for controlling a vehicle as in claim 2, further comprising:

a plurality of switching gate means coupled to said ground elements and actuated thereby for progressively transmitting the output signals of said adding devices to said vehicle.

5. An apparatus for controlling a vehicle as in claim I, wherein:

said control means includes a first plurality of control devices for regulating said speed and spacing on said main line,

a second plurality of control devices for regulating said speed andspacing on said first branch line; and,

a third plurality of control devices for regulating said speed and spacing on said second branch line.

6. An apparatus for controlling a vehicle as in claim 5, further comprising:

comparing-means coupled to said control devices for comparing the outputs of at least one control device in said second plurality of control devices and at least one control device in said third plurality of control devices, and for controlling said vehicle in said zone in response to the smaller of said compared outputs.

7. An apparatus for controlling a vehicle as in claim 1, further comprising:

comparing means coupled to at least two of said adding devices located adjacet to said zone for comparing the outputs thereof.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3963203 *Jan 30, 1975Jun 15, 1976Westinghouse Air Brake CompanyAutomatic control system for railroad interlocking
USRE39011Feb 26, 2003Mar 14, 2006Cattron Intellectual Property CorporationRemote control system for a locomotive
USRE39210Feb 26, 2003Aug 1, 2006Cattron Intellectual Property CorporationRemote control system for a locomotive
USRE39758Nov 14, 2005Aug 7, 2007Cattron Intellectual Property CorporationRemote control system for a locomotive
Classifications
U.S. Classification246/63.00R, 246/187.00C, 246/167.00R, 104/300
International ClassificationB61L3/00, B61L3/18
Cooperative ClassificationB61L3/185
European ClassificationB61L3/18A