JP7580353B2 - Step Unit - Google Patents

Description

This disclosure relates to a step unit.

The Electronic Toll Collection System (ETC (registered trademark)) used on toll roads can collect tolls from vehicles traveling in the toll gate lane by communicating wirelessly with the vehicles.

Some electronic toll collection systems use a vehicle type discrimination device installed on the lane of the toll booth to determine the vehicle type classification (such as standard vehicle, large vehicle, etc.) of a passing vehicle. For example, the vehicle type discrimination device measures the number of axles of the vehicle by counting the number of pressures made by the tires through a footplate-type pressure detection sensor (hereinafter also referred to as "footplate" or "footplate unit") laid on the road surface of the lane, and determines the vehicle type classification based on the measurement results (see, for example, Patent Document 1).

Some treads laid on road surfaces can detect various information about a vehicle, such as the number of axles, the width of the vehicle's wheels, and the distance between the wheels connected to one axle (tread width). These treads have two conductive contacts arranged vertically and facing each other in multiple rows along the length of the body, and when a vehicle tire steps on the tread, the two upper and lower contacts belonging to the stepped area come into contact. The tread outputs a signal that indicates the presence or absence of conductivity for each contact. This signal makes it possible to obtain the above information about the passing vehicle.

In recent years, the practical application of MLFF (multi-lane free-flow) toll collection systems that can charge vehicles traveling on main roads consisting of multiple lanes has been progressing. Here, in the case of a toll collection system applied to the above-mentioned toll gates, it is sufficient to lay a footplate that covers the width of a single lane (a lane separated by an island) at the toll gate, but in an MLFF toll collection system, it is necessary to lay a footplate that extends across the entire width of the main road consisting of multiple lanes.

However, in order to cover the entire width of a normal multi-lane road, the overall length of the step must be 10 meters or more, and it is difficult to manufacture such a step as a single item. Therefore, one method of realizing an MLFF-type toll collection system is to prepare multiple step plates of conventional length manufactured as a single item (hereinafter also referred to as step unit), and lay these out across the entire width of the lane and connect them together.

JP 2003-303396 A

In conventional foot pedal units (foot pedals), a serial-parallel conversion board for signal transmission is arranged in the same direction as the multiple contacts arranged in the longitudinal direction. In this structure, no contacts are arranged in the area where the serial-parallel conversion board is arranged. Therefore, even if such foot pedal units are arranged in the width direction of multiple lanes, the area in the longitudinal direction of each foot pedal unit where the serial-parallel conversion board is arranged (area where no contacts are arranged) becomes a dead zone, making it difficult to detect the axle (tire pressure) uniformly in the entire area in the lane width direction across multiple lanes.

This disclosure was made in consideration of the above-mentioned problems, and aims to provide a step unit that can reliably detect vehicle information and improve the accuracy of vehicle type identification.

In order to achieve the above object, a foot pedal unit according to one embodiment of the present disclosure is a foot pedal unit that extends in the lane width direction of a lane and detects the state when a wheel of a vehicle traveling on the lane has passed over it, and includes lower contacts provided on a plurality of lower contact boards arranged in the lane width direction, upper contacts that are spaced apart from the lower contacts and are capable of contacting the lower contacts from above, a board provided below the plurality of lower contact boards and having a serial-parallel conversion board arranged inside the board, a first signal cable that connects the serial-parallel conversion board and the lower contact board and transmits a detection signal generated by contact between the lower contacts and the upper contacts, and a second signal cable that transmits the detection signal converted by the serial-parallel conversion board to the outside of the foot pedal.

The footboard unit of the present invention can reliably detect vehicle information and improve the accuracy of vehicle type identification.

FIG. 2 is a plan view showing an overall configuration in which a step unit according to an embodiment is arranged in a lane, as viewed from above. 1 is a plan view showing the overall configuration of a step unit according to an embodiment of the present invention, viewed from above. 3 is a cross-sectional view of line AA shown in FIG. 2 according to the embodiment. 3 is a cross-sectional view of line BB shown in FIG. 2 according to the embodiment. 13 is a plan view seen from above showing an arrangement of lower contacts according to the embodiment. FIG. FIG. 2 is a perspective view showing a connection connector in the step unit according to the embodiment. 13 is a diagram showing a connection state of signal cables in a plurality of footboard units according to an embodiment of the present invention. FIG. 11A to 11C are diagrams illustrating a wheel detection method in the step unit according to the embodiment. A first plan view seen from above showing the joint structure between the steps of the step unit related to the first modified example. A second plan view seen from above showing the joint structure between the steps of the step unit relating to the second modified example.

The following describes a step unit according to an embodiment of the present disclosure with reference to the drawings. This embodiment shows one aspect of the present invention, does not limit the invention, and can be modified as desired within the scope of the technical concept of the present invention.

First Embodiment
The step unit according to the first embodiment will be described in detail with reference to FIGS. 1 to 7. FIG.

(Overall configuration of the footboard unit)
Fig. 1 is a plan view from above of the overall configuration of a step unit according to the first embodiment arranged in a lane. Fig. 2 is a plan view from above of the overall configuration of the step unit according to the first embodiment. Fig. 3 is a cross-sectional view taken along line A-A in Fig. 2. Fig. 4 is a cross-sectional view taken along line B-B in Fig. 2. Fig. 5 is a plan view from above showing the arrangement of the lower contacts. Fig. 6 is a perspective view showing a connection connector in the step unit. Fig. 7 is a diagram showing the connection state of signal cables in a plurality of step units.

The multiple pedal units 1 and vehicle type discrimination device 12 of this embodiment are employed as part of the configuration of an MLFF-type toll collection system.

As shown in FIG. 1, vehicle A using a toll road travels on one lane L of a main road consisting of multiple lanes L (four in the example of FIG. 1). In the following description, the direction in which lane L extends (±X direction) is also referred to as the "lane direction", and the direction (±Y direction) horizontally perpendicular to the lane direction (±X direction) is also referred to as the "lane width direction". The +X direction side in the lane direction (±X direction) is also referred to as the "downstream side" or the "rear side in the traveling direction" of vehicle A. The -X direction side in the lane direction (±X direction) is also referred to as the "upstream side" or the "front side in the traveling direction" of vehicle A. The +Y direction side in the lane width direction (±Y direction) is also referred to as the "left side in the lane width direction" or the "left side in the traveling direction" of vehicle A. The -Y direction side in the lane width direction (±Y direction) is also referred to as the "right side in the lane width direction" or the "right side in the traveling direction" of vehicle A. Additionally, the direction (±Z direction) perpendicular to the plane including the lane direction (±X direction) and lane width direction (±Y direction) is also referred to as the "up-down direction" (the +Z direction is the upper side, and the -Z direction is the lower side).

The step unit 1 shown in FIG. 1 is a step-type pressure sensor used to detect the number of axles of a vehicle passing over its upper surface. As shown in FIG. 1, the step unit 1 is installed on the road surface with its upper surface 1a exposed on a main road consisting of multiple lanes L. The multiple step units 1 are arranged across the entirety of the multiple lanes L with their longitudinal directions facing the lane width direction (±Y direction) of the lanes L. By arranging the multiple step units 1 in a straight line across the entirety of the multiple lanes L in this way, it is possible to detect the passage of tires of all vehicles traveling on the multiple lanes L.

Each pedal unit 1 detects whether it has been stepped on by a tire T of vehicle A by the presence or absence of electrical continuity. The electrical signal (detection signal) detected by each pedal unit 1 is drawn from each pedal unit 1 by a second signal cable 7 and transmitted to an external vehicle type discrimination device 12 (described later).

As shown in Figures 3 and 4, the footboard unit 1 has a lower contact 2, an upper contact 3, a base 4, a serial-parallel conversion board 5, a first signal cable 6, and a second signal cable 7. The lower contact 2, the upper contact 3, the base 4, the serial-parallel conversion board 5, the first signal cable 6, and a portion of the second signal cable 7 are housed inside the housing 8.

The container 8 is a hollow plate-shaped member that is rectangular in the lane width direction (±Y direction) when viewed from above and has a predetermined thickness. The container 8 has an upper wall 81, a lower wall 82, and side walls 83 located on each of the four sides (see FIG. 6). At least the upper wall 81 of the container 8 is made of an elastic member, such as rubber, that can elastically deform in the vertical direction (±Z direction).

The lower contacts 2 are formed as a wiring pattern on the lower contact board 20, which is a rectangular printed circuit board extending in the lane width direction (±Y direction), and are arranged at equal intervals on the surface of the lower contact board 20. The lower contact boards 20 are arranged in the lane width direction (±Y direction) (see FIG. 3), and are also arranged in the lane direction (±X direction) (see FIG. 4). With this configuration, the lower contacts 2 are arranged in the lane direction (±X direction) and the lane width direction (±Y direction) (see FIG. 5). As shown in FIG. 5, the lower contacts 2 arranged on the footboard unit 1 on both sides of the lane width direction (±Y direction) are arranged in close proximity to the side walls 83 of the housing 8.

The lower contacts 2 are connected to the connectors 21 of the lower contact substrates 20 (see FIG. 3). Furthermore, a core member 9 through which the first signal cable 6 passes is provided between the lower contact substrates 20 and the substrate 4 (see FIG. 3 and FIG. 4).

As shown in FIG. 4, the core member 9 is formed of, for example, aluminum. The core member 9 has a support plate 91 and side plates 92 extending in the up-down direction (±Z direction) from both ends of the support plate 91 in the lane direction (±X direction). The core member 9 has an upper core portion 9A above the support plate 91 that can accommodate a lower contact board 20 having a lower contact 2 and an upper contact 3, and a lower core portion 9B below the support plate 91 that can accommodate a first signal cable 6. The first signal cable 6 connected to the connector 21 (see FIG. 3) of the lower contact board 20 is arranged to pass through the lower core portion 9B below the support plate 91.

3 and 4, the upper contact 3 faces the lower contact 2 with a gap therebetween and is arranged so as to be able to contact the lower contact 2 from above. The upper contact 3 is arranged on the underside of the upper wall 81 of the housing 8, and when the upper wall 81 is stepped on by the tire T, the upper contact 3 is pushed downward together with the deformation of the upper wall 81 at the stepped portion and contacts the lower contact 2. The upper contact 3 is formed of a conductor in a flat plate shape, and its width dimension (length in the ±Y direction) is approximately the same as that of the lower contact 2. The multiple upper contacts 3 are also arranged in the lane direction (±X direction) in the same manner as the lower contacts 2.

4, the technical significance of arranging the four contact bodies (lower contacts 2 and upper contacts 3) side by side along the lane direction (±X direction) is as follows: That is, by referring to the Off→On order or On→Off order of the four lower contacts 2, the vehicle type discrimination device 12 can determine whether the vehicle is moving forward, backward, or has changed its direction of travel along the way.
The number of upper contacts 3 is not limited to the same as that of the lower contacts 2 (four in the figure), and it is also possible, for example, to use a single upper contact body with a width approximately equal to that of the footboard unit 1. By sharing the upper contact body in this way, it becomes possible to detect the electrical continuity of each of the lower contacts.

In the tread unit 1, when a tire T of a vehicle A passes over, the upper contact 3 is elastically deformed by the force of the tire T acting through the upper wall 81 of the housing body 8, and the elastically deformed upper contact 3 comes into contact with the lower contact 2, establishing electrical continuity. Whether or not the tire T is passing over the tread unit 1 is detected based on the presence or absence of electrical continuity between the lower contact 2 and the upper contact 3.
Furthermore, the tread unit 1 is configured to be able to detect not only that it has been stepped on by a tire T of the vehicle A (axle detection) but also the position where it has been stepped on, the width of the tire T, and the spacing (tread width) between tires T connected to the same axle by determining which lower contact point 2 has come into contact.

The first signal cable 6 is, for example, a flexible printed cable (FPC). The first signal cable 6 connects the serial-parallel conversion board 5 and the lower contact board 20, and transmits a detection signal generated by contact between the lower contact 2 and the upper contact 3. The first signal cable 6 passes between the core member 9 and the board 4 and is connected to the serial-parallel conversion board 5.

As shown in FIG. 4, the base 4 is provided below the multiple lower contact boards 20, specifically below the multiple core members 9. The base 4 is a single metal plate (e.g., 5 mm thick SS (soft iron)) formed to extend throughout the entire inside of the footboard unit 1 in the lane direction (±X direction) and lane width direction (±Y direction), and holds the entire footboard unit 1. The base 4 provides a certain rigidity to the footboard unit 1 to prevent it from bending and deforming, for example, when the footboard unit 1 is carried.

The base 4 has a top plate 41 extending in the lane width direction (±Y direction) and side plates 42 extending downward from both ends of the top plate 41 in the lane direction (±X direction). The base 4 has a storage section 4a below the top plate 41 that can store the serial-parallel conversion board 5 and the second signal cable 7.

3, the serial-parallel conversion board 5 has a power supply integrated circuit 51 and a latch integrated circuit 52 disposed on a board. The serial-parallel conversion board 5 also has a first connector 53 to which the first signal cable 6 is connected, and a second connector 54 to which the power supply cable 11 drawn in from the outside of the housing 8 is connected.
The power cable 11 is led into the housing 8 through an insertion portion (connector 84 shown in FIG. 6 ) provided on a side wall 83 of the housing 8 .

The second signal cable 7 transmits the detection signal, which is a serial signal converted from a parallel signal (a collection of signals indicating whether or not each of the multiple lower contacts 2 is in contact) by the serial-parallel conversion board 5, to the outside of the footboard unit 1. The second signal cable 7 is pulled out to the outside from the side wall 83 of the housing 8. As shown in FIG. 7, the second signal cable 7 pulled out from the housing 8 is connected to the vehicle type discrimination device 12. That is, each second signal cable 7 pulled out from the side of the multiple footboard units 1 arranged in the lane width direction (±Y direction) transmits a detection signal to the vehicle type discrimination device 12.

The vehicle type discrimination device 12 receives detection signals from each pedal unit 1. Based on the detection signals received from each pedal unit 1, the vehicle type discrimination device 12 measures the number of presses (number of axles) by the tire T of vehicle A and discriminates the vehicle type category.

As shown in FIG. 1, in this embodiment, vehicle detectors 13 are installed directly above each lane L through the gantry. The vehicle detectors 13 irradiate detection light (laser light) downward (to the road surface) and measure the characteristics of the reflected light, making it possible to detect the passage (entrance and exit) of vehicle A at the irradiation position. The vehicle type discrimination device 12 can then combine the detection results of the tire T by the tread unit 1 and the detection results of the passage of vehicle A by this vehicle detector 13 to count the number of times the tire T is pressed on one vehicle A (i.e. the number of axles).

(Method of detecting wheels using a tread unit)
A method of detecting wheels using the step unit 1 having the above-mentioned configuration will be described with reference to Fig. 8. Fig. 8 is a diagram showing a method of detecting wheels in the step unit.

Specifically, Fig. 8 shows bit strings obtained from the lower contact 2 in the detection range P shown in Fig. 5 when the tire T of the vehicle A passes through the lower contact 2 provided in this detection range P, arranged in order of time t. In the left diagram of Fig. 8, the elapsed time increases as the arrow of time t points. In the diagram, "0" indicates a position not stepped on by the tire T at each time t, and "1" indicates a position stepped on by the tire T at each time t. Based on the detection area "1" obtained from the bit string shown in Fig. 8, the movement of the tire (tire T) shown in the right diagram of Fig. 8 can be assumed.
As described above, the vehicle type discrimination device 12 of this embodiment creates a time-space image as shown in the left diagram of Figure 8 using a bit string obtained from a representative lower contact 2 (lower contact 2 within detection range P) out of the four lower contacts 2 arranged in the lane direction within each tread unit 1.
Note that the vehicle type discrimination device 12 according to other embodiments is not limited to this form, and for example, the device may be configured to obtain information equivalent to one row of the time-space image shown in the left diagram of FIG. 8 by taking the logical sum of the bit strings of the above-mentioned four lower contacts 2 obtained at a certain moment (the same time).

Then, from the detection result of the passage of vehicle A by the vehicle detector 13 described above, the entry detection time and exit detection time of this vehicle A are received, and by linking this with the bit string by the tread unit 1, it is possible to identify the movement of the tires T of vehicle A and to measure the number of axles of vehicle A.

(Action and Effect)
As described above, the step unit 1 according to this embodiment is configured such that the serial-parallel conversion board 5 is disposed further below and inside the base 4 which is disposed below the lower contact board 20. In other words, the step unit 1 according to this embodiment is configured such that the arrangement space for the lower contacts 2 and the arrangement space for the serial-parallel conversion board 5 are separated in the up-down direction (±Z direction) of the step unit 1 via the base 4.

With this configuration, the serial-parallel conversion board 5 can be positioned so that it overlaps with the position of the lower contacts 2 when the footboard unit 1 is viewed from above, while avoiding spatial interference between them. As a result, as shown in Figure 5, the footboard units 1 can be positioned so that the lower contacts 2 are spread out close to the side wall 83 of the housing 8, so that the width of the dead zone formed at the connection part of each footboard unit 1 can be reduced when the footboard units 1 are arranged side by side as shown in Figure 1.

As described above, the step unit 1 according to this embodiment can measure the number of axles with high accuracy.

In addition, with the footboard unit 1 according to this embodiment, the first signal cable 6 is routed through the inside of the core member 9, so that the first signal cable 6 can be positioned below the lower contact board 20 and connected to the serial-parallel conversion board 5.

Although each embodiment of the footboard unit has been described above, this disclosure is not limited to the above-mentioned embodiments and can be modified as appropriate without departing from the spirit of the disclosure.

(First Modification)
For example, a step unit 1A according to a first modified example shown in Fig. 9 may be used. In the step unit 1A, the inter-step end portion 1b in the lane width direction (±Y direction) is inclined with respect to the lane direction (±X direction) when viewed from above.

(Second Modification)
Also, a step unit 1B according to a second modification shown in Fig. 10 may be used. In the step unit 1B, a step is formed in the inter-step end portion 1c in the lane width direction (±Y direction) in the lane direction (±X direction) when viewed from above.

By configuring the first and second modified examples as shown in Figures 9 and 10, the four contact bodies (lower contact 2, upper contact 3) arranged in the lane direction (±X direction) are shifted in the lane width direction (±Y direction). As a result, each of the four contact bodies is arranged to complement the dead zone extending in the lane width direction. In this case, the vehicle type discrimination device 12 creates a time-space image (see the left diagram in Figure 8) by taking the logical sum of the logical data of the four lower contacts 2. In this way, the area in which the dead zone is formed over the entire width in the lane direction (±X direction) is reduced, so that the width dimension in the lane width direction (±Y direction) of the dead zone formed at the tread ends 1b and 1c can be further reduced.

In addition, in this embodiment, the material of the upper wall 81 of the container 8 is made of rubber, but it is not limited to rubber, and other materials may be used as long as they are elastic members that can be elastically deformed in the vertical direction (±Z direction).

In addition, in this embodiment, the core member 9 is provided between the lower contact substrate 20 and the base 4, but it is also possible to omit the core member 9. The shape and dimensions of the core member 9 can also be changed as appropriate. Furthermore, the material of the core member 9 is not limited to being aluminum.

Furthermore, in this embodiment, the lower contacts 2 are arranged at equal intervals along the lane direction (±X direction) and the lane width direction (±Y direction), but are not limited to such an arrangement.

In addition, the components in the above-described embodiments may be replaced with well-known components as appropriate without departing from the spirit of the present invention, and the above-described embodiments may be combined as appropriate.

<Additional Notes>
The step unit described in the above embodiment can be understood, for example, as follows.

(1) According to the first aspect, the foot pedal unit 1 extends in the lane width direction (±Y direction) of the lane L and detects the state when a tire T of a vehicle A traveling on the lane L has passed over it. The foot pedal unit 1 includes a lower contact 2 provided on a plurality of lower contact substrates 20 arranged in the lane width direction (±Y direction), an upper contact 3 arranged at a distance from the lower contact 2 and capable of contacting the lower contact 2 from above, a board 4 provided below the plurality of lower contact substrates 20 and having a serial-parallel conversion board 5 arranged inside the board, a first signal cable 6 that connects the serial-parallel conversion board 5 and the lower contact substrate 20 and transmits a detection signal generated by contact between the lower contact 2 and the upper contact 3, and a second signal cable 7 that transmits the detection signal converted by the serial-parallel conversion board 5 to the outside of the foot pedal.

(2) According to the second aspect, the lower contact 2, the upper contact 3, the lower contact board 20, the board 4, the first signal cable 6, and the serial-parallel conversion board 5 are housed in a housing 8 having at least an upper wall 81 made of an elastic material that can elastically deform in the vertical direction (±Z direction), and the second signal cable 7 is pulled out to the outside from a side wall 83 of the housing 8.

(3) According to the third aspect, a core member 9 is provided that is disposed between the lower contact substrate 20 and the substrate 4 and through which the first signal cable 6 passes.

(4) According to the fourth aspect, the end between the treads in the lane width direction (±Y direction) is inclined with respect to the lane direction (±X direction) when viewed from above.

(5) According to the fifth aspect, the end between the treads in the lane width direction (±Y direction) has a step formed in the lane direction (±X direction) when viewed from above.

1, 1A, 1B Step unit (step unit)
Reference Signs List 2 Lower contact 3 Upper contact 4 Board 5 Serial-parallel conversion board 6 First signal cable 7 Second signal cable 8 Container 9 Core member 11 Power cable 12 Vehicle type discrimination device 20 Lower contact board 81 Upper wall A Vehicle L Lane T Tire X Lane direction Y Lane width direction Z Up-down direction

Claims (5)

A step unit extending in a lane width direction of a lane and detecting a state in which a wheel of a vehicle traveling on the lane has passed,
Lower contacts provided on a plurality of lower contact substrates arranged in the lane width direction;
an upper contact that is disposed with a gap therebetween and is capable of contacting the lower contact from above;
a substrate provided below the plurality of lower contact substrates and having a serial-parallel conversion substrate disposed therein;
a first signal cable that connects the serial-parallel conversion board and the lower contact board and transmits a detection signal generated by contact between the lower contact and the upper contact;
A second signal cable that transmits the detection signal converted by the serial-parallel conversion board to the outside of the footboard;
A footboard unit comprising: the lower contact, the upper contact, the lower contact substrate, the base, the first signal cable, and the serial-parallel conversion substrate are accommodated in a housing having at least an upper wall made of an elastic member that is elastically deformable in the vertical direction;
The second signal cable is pulled out from a side wall of the housing to the outside.
2. The footboard unit according to claim 1. The footboard unit according to claim 1 or 2, further comprising a core member disposed between the lower contact board and the base and through which the first signal cable passes. The end portion between the treads in the lane width direction is inclined with respect to the lane direction when viewed from above.
A step unit according to any one of claims 1 to 3. The end portion between the treads in the lane width direction has a step formed in the lane direction when viewed from above.
A step unit according to any one of claims 1 to 3.

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