JPH0565003B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a trolley wire wear measuring device mounted on an electric inspection vehicle for rigid structure overhead wires (trolley wires) such as subways.

[Prior Art] Since the trolley wire of an electric railway gradually wears out due to sliding contact with the pantograph of the vehicle, the amount of wear is measured using an electric inspection car.

The method of measuring wear on trolley wires has evolved from the old manual method using a micrometer to the optical method using an electric inspection vehicle, which has undergone gradual improvements until today. .

FIG. 6a shows an early optical system in which a parallel light beam 4 is irradiated onto the trolley wire 1 from a light source 2 in a perpendicular direction using a lens 3. This light beam 4 is focused by a lens 5 at a position across the trolley wire 1, and a light receiver 6 detects the amount of light received. The amount of light received decreases because the portion of the cross section of the trolley wire 1 relative to the height h becomes a shadow.
The height h can be known by measuring the relationship between the height h and the amount of light received in advance. This method is called the light amount method, and the height h is called the remaining diameter. Note that 7 in the figure is a hanger for suspending the trolley wire 1, which is provided at regular intervals.

The light intensity type has many safety and environmental problems because it requires a set of precise optical equipment installed on the roof of the vehicle, and the image pickup tube type shown in Figure 6b was subsequently used, which is mounted on the roof of the vehicle. A light source 2 provided above irradiates a light beam 4 onto the lower surface (sliding surface) 1-1 of the trolley wire 1 from diagonally below. Since the sliding surface 1-1 is a rough surface, a portion of the reflected light travels downward through diffused reflection, and the lens 5 provided in the vehicle forms an image on the imaging tube 10 to measure the width W of the sliding surface. Since there is a simple mathematical relationship between W and h, the remaining diameter h can be determined by calculation.

A major drawback of the above-mentioned image pickup tube method (the same applies to the light amount method) is that the S/N ratio decreases during the day, so measurements are limited to nighttime. As a solution to this problem, a laser beam method was developed that provides a high luminous intensity.

This is shown in Figures 6c and d. In figure c, the laser beam 11 is transmitted through three mirrors 12-1, 12-
2 and 12-3 form a narrow spot and irradiate the sliding surface 1-1 vertically upward. This reflected light returns via the same path, branches along the way, and enters the light receiver. Note that the trolley wire 1 is deviated left and right in a zigzag pattern at a constant pitch in a horizontal plane in order to uniformly wear the contact surface of the pantograph. Therefore, the laser beam 11 is scanned so as to cover the deviation width D as shown in FIG. d.

Recently, the subway network has been expanding, and in order to save on tunnel construction costs, the cross-sectional area of the tunnels has been reduced, and the ceiling height has been made much lower than before. In this case, a flexible overhead wire such as a conventional trolley wire cannot be used, but a rigid overhead wire that supports the trolley wire with a rigid support 13 shown in FIG. 1 is used.

The rigid support 13 is an aluminum rail 13-1 with a T-shaped cross section attached to the ceiling of the tunnel, and an ear 13-2 is used to connect the trolley wire 1 to the rail 13-1.
are fixed continuously. In this case,
None of the conventional wear measurement methods described above can be used. In other words, the light quantity method is of course impossible in principle, and the image pickup tube method and laser beam method, which utilize the reflected light from the sliding surface, have the reflected light from the claw part A of the ear 13-2 in Fig. 1a. Reflected light in the range indicated by 14 is received and causes an error. The surface of the claw part A has a reflectance comparable to or higher than that of the sliding surface 1-1, and the intensity of the diffusely reflected light shown by the dotted line in FIG. 2B is strong.

For the reasons stated above, there is a need for a wear measurement method that is effective for rigid overhead wires in place of the various methods. However, since there is no need to distinguish between day and night in subways, it is said that the use of a strong luminous object such as a laser beam is not necessarily a necessary condition.

[Object of the Invention] In view of the above-mentioned circumstances, it is an object of the present invention to provide a trolley wire wear measuring device that can measure the width of the sliding surface of a trolley wire while eliminating the influence of supports for rigid overhead wires.

[Means for Solving the Problems] This invention uses a method of measuring the sliding surface width optically, but in order to avoid receiving the reflected light from the claw portion A, the following measures are taken. .

First, on the light projecting side, as shown in FIGS. 2a and 2b, the light beam from the light source 2 is passed through the slit plate 15 and converted into a sufficiently narrow beam 17 by the cylindrical lens 16, at right angles to the length direction of the trolley wire 1. and the light projection direction is set to an incident angle θ ₁ inclined in a plane perpendicular to the sliding surface 1-1, and the sliding surface 1-1 is irradiated to create a light band 18. The light beam 17 also irradiates the nail part A, and a light band 18 appears also in this part.

Next, on the light receiving side, as shown in Figures a and c, the light is received by the lens 5 in the direction of reflection angle θ ₂ , and the light band 1
8 (hereinafter simply referred to as an image) is formed on a linear image sensor 19 to read the width of the sliding surface 1-1. In this case, a slit plate 20 is also used to form an image on the linear image sensor 19 of only the portion of the image 18a that corresponds to the sliding surface 1-1.

Figure 3 a and b show the light band 18 and the image 1 generated on the light receiving side.
8a and the action of the slit plate 20 on it, FIG. 8a shows the light zone 18, and FIG. The image 18 is in the slit 20a of the slit plate 20.
Only the part a of the sliding surface 1-1 hits, but the part a of the claw part protrudes and is cut. It should be noted that since the side surface 1-2 (FIG. 1b) of the trolley wire 1 has a low reflectance, the luminous intensity of the image B at this portion is weak and will not cause a measurement error.

Since the method of the present invention utilizes the effect of such a slit, it is desirable that the width of the slit 20a is as narrow as possible.
In order to cut out other unnecessary parts, it is necessary to consider the optimum values of the light projection angle θ ₁ and the light reception angle θ ₂ . Furthermore, when the inspection vehicle runs, it is unavoidable that the measuring optical system is subject to vibrations, which causes fluctuations in the height of the trolley wire relative to the optical system, and also takes into account the positional deviation of the image 18a relative to the slit 20a. must enable stable and reliable measurements. These issues will be discussed below.

FIG. 4a is a model diagram for examining the positional relationship between the image at the light projection angle θ ₁ and the light reception angle θ ₂ , and shows a vertical plane in the line direction of the trolley wire 1. Now, the height of the sliding surface 1-1 and the height of the claw portion A are expressed by levels P and Q, respectively. Here, the image of the side surface 1-2 of the trolley wire 1 is ignored, and the surface of the claw portion A is assumed to be a horizontal plane. The projected light beam at the projection angle θ ₁ is reflected by a point p on the sliding surface P and a point q on the claw portion Q, and is directed toward a light receiving angle θ ₂ . Now, if the difference in height between levels P and Q is d, then the length D between points pq is D=d/cosθ ₁ ...(1) When viewed from the direction of the light reception angle θ ₂ , the interval D ₁ is expressed by the following equation.

D ₁ =dsin(θ ₁ +θ ₂ )/cosθ ₁ (2) Since the reflected light at point q should be cut by the slit, it is desirable that D and D ₁ be large. For this purpose, it is better for θ ₁ to be large in equation (1), and in equation (2), D ₁ becomes the maximum D when (θ ₁ +θ ₂ )=90°. That is, it is optimal for the time being to make the light projection direction as horizontal as possible and the light reception direction as close to vertical.

However, if the height of the trolley wire changes with respect to the optical system, this condition will not be optimal. This is because increasing θ ₁ and increasing the distance between points p and q will have a large effect on changes in the position of the real image due to fluctuations in the height of levels P and Q, which will be a negative factor. . This point will be discussed below.

In FIG. 4b, it is assumed that the levels P ₁ and Q ₁ change to P ₂ and Q ₂ by Δh. Let B be the width of the projected light beam on the diagram (hereinafter simply referred to as width), and its center is point p ₁ at P ₁ ,
Let it be reflected at point p ₂ of P ₂ , point q ₁ of Q ₁ , and point q ₂ of Q ₂ , respectively. The width of the interval between points p ₁ and p ₂ viewed from the direction perpendicular to the light projection, that is, the moving distance ΔW of the light band 18, is ΔW=Δh/cosθ ₁ (3). When this ΔW is large, the image 18a may come off the slit 20a due to the height change Δh. In order to make ΔW smaller than Δh,
The smaller the angle θ ₁ is, the more advantageous it is, as shown above. As described above, the conditions for cutting out the unnecessary portion of the image 18 and the conditions for stably receiving light from the necessary portion within the slit despite changes in height are contradictory with respect to angle _θ1 .

Therefore, in the present invention, it is proposed to make the width of the light band somewhat wide so that the image 18a does not fall out of the slit 20a even when the height changes, and the conditions for this will be discussed here.

In Fig. 4b, the luminous flux of width B is at each point p ₁ , p ₂ ,
The width ΔB of the light band formed by q ₁ and q ₂ viewed from the receiving direction perpendicular to the light emission direction is expressed as ΔB=Btanθ ₁ (4). Image position change ΔW due to height difference Δh (here, the scale of the light receiving lens is not considered)
If the width B is selected so as to cover ΔW≦ΔB...(5), even if there is a change in height Δh, the points p ₁ to _{p 2}
A certain part of the image of the light band falls within the slit.

On the other hand, if ΔB is increased, there is a risk that the light band at point _q1 will enter the slit. The condition for preventing this is the following equation.

ΔB＜D……(6) The following relational expression can be obtained from the above equations (1) to (6).

Δh≦Bsinθ ₁ <d ……(7) Equation (7) means first that the height fluctuation Δh
must be smaller than the height difference d between the sliding surface level P and the claw level Q, and for this purpose, a mechanism is required to keep the height of the trolley wire constant with respect to the optical system. However, there is a limit to this, and therefore there is a lower limit to the measurable d. Next, the width B of the projected light beam can be made smaller by increasing the angle θ ₁ . This is consistent with the condition for increasing D in equation (1). Note that in sin θ ₁ , increasing θ ₁ has the advantage that B can be decreased and the luminous intensity of the light band can be increased.

To summarize the above study results, the light projection angle θ ₁ is set as large as the mechanism allows, for example, 60° to 80°, and the light receiving direction is perpendicular to the light projecting direction. This minimizes the risk of the image of the pawl entering the slit. In addition, the mechanism is designed to keep the height interval between the optical system and the trolley wire as constant as possible, and to compensate for any height changes that may occur.
By setting the width B of the emitted light beam to the value of the emitting angle θ ₁ , the formula is
(7) shall be satisfied. The width B is a design issue that can be set by the slit width of the slit plate 15 on the light projecting side based on the focal length of the lens 16 on the light projecting side.

[Function] As is clear from the above explanation, in the trolley wire wear measuring device according to the present invention, based on the examination of the light projection angle θ ₁ and the light reception angle θ ₂ according to FIG. 4a, As shown in each figure, the incident angle θ ₁ is larger from below with respect to the sliding surface 1-1 of the trolley wire.
(60° to 80°, light zone 18 perpendicular to the trolley wire)
By irradiating with , the position where the light band hits the sliding surface and the position where the light band hits the claw part A of the support ear 13-2 of the trolley wire are separated as much as possible. In addition, by setting the light receiving direction to be perpendicular to the light emitting direction (θ ₁ + θ ₂ = 90°),
The distance between the part of the image relative to the sliding surface and the part relative to the pawl is maximized, thereby eliminating unnecessary and harmful images of the pawl by the slit and eliminating their influence.

Furthermore, by widening the width B of the emitted light beam within the range shown by equation (7), even when there is a fluctuation Δh in the height of the sliding surface relative to the projecting and receiving optical systems, the image relative to the sliding surface remains within the slit. This allows stable measurement. In this case, if the width B is increased too much, the image of the claw portion will enter the slit and cause an error, so the upper limit is limited by equation (7).

[Example] Figures 5a to 5c show an example of the trolley wire wear measuring device according to the present invention, and in Figure a,
A light beam 17 is irradiated onto the sliding surface 1-1 of the trolley wire 1 from a light projecting section consisting of a light source 2, a slit plate 15, and a lens 16 to form a light belt 18. The direction of the light band 18 is perpendicular to the trolley wire 1, and the angle of incidence .theta.1 with respect to the sliding surface 1-1 is large, ranging from 60 DEG to 80 DEG. The width B of the projected light beam is determined according to the condition of equation (7), and the width of the slit of the slit plate 15 is set to match this condition.

Next, the light receiving section consists of a lens 5, a slit plate 20, and a linear image sensor 19, and the light receiving angle .theta.2 is perpendicular to the light projection direction. In this case, the width of the slit is the same as the width of the linear image sensor 19 when the sensitivity width of the element is sufficiently narrow, and can be omitted in some cases.
However, if the sensitivity width of the element is too large, it is necessary to set the slit width to a value that allows unnecessary portions of the real image to be cut out.

Now, as stated at the beginning, since the trolley wire has deviations in its installation position, the light projecting section and the light receiving section must cope with this deviation width. FIGS. 5b and 5c show an embodiment for this purpose; in FIG. 5b, the trolley wire moves within the range of the deviation interval H, as indicated by 1a, 1b, and 1c. In concrete terms, H is approximately 200 mm. The light projecting section includes a light source 2 slightly longer than this H, a slit plate 15, and a cylindrical lens 16. A neon or sodium tube is suitable as the light source 2.

Figure c shows the light receiving section, in this case, the light receiving lens 5
As an example, the deviation width H is divided into three parts due to the aberration. Lenses 5a and 5 are provided in each section, respectively.
b, 5c, slit plates 20a, 20b, 20c and linear image sensors 19a, 19b, 19
Three sets of light receivers consisting of c are arranged. The boundaries of each division width are overlapped with each other by the optical system.
The addresses of the elements of each linear image sensor are adjusted and connected.

[Effects of the Invention] As is clear from the above detailed explanation, the trolley wire wear measuring device according to the present invention can improve the rigid overhead wire type used in subways, etc., which was impossible with the conventional method. By irradiating the trolley wire with a light beam at a high angle of incidence and receiving the light at a right angle, it is possible to measure the sliding surface width. In particular, in order to ensure the reliability of the measurements, we will examine the relationship between the light emission and reception angles and the position of the image of the light band generated on the receiver, as well as the movement of the image on the slit due to height fluctuations of the trolley wire.
An analysis was conducted using a model, and based on the results, it was proposed using mathematical formulas to expand the width of the light zone to a safe range as a countermeasure against height fluctuations, ensuring sufficient stability of measurement. ing. As a result, the practicality of the trolley wire wear measuring device according to the present invention is improved, and the effect contributing to the wear measurement of rigid overhead wires is excellent.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing a cross section of a rigid overhead wire, which is the object of the present invention, FIG. It is. Figures 2a, b, and c are configuration diagrams of the optical system of the trolley wire wear measuring device according to the present invention, respectively. Figure a is a vertical cross-sectional view of the rigid overhead wire in the line direction, and Figure b is a vertical cross-sectional view of the overhead wire of the light projecting section. Right-angle sectional view, Figure c is a right-angled sectional view to the overhead wire of the light receiving section. Figures 3a and 3b are explanatory diagrams of the light zone in the trolley wire wear measuring device according to the present invention, respectively. Figure a is a diagram of the light zone seen from the bottom surface of the rigid overhead wire, and Figure b is an illustration of the light zone on the slit plate of the light receiving section. It is a diagram of an image of a light band. Figures 4a and 4b are model diagrams for examining the light emitting and receiving angles and the width of the light zone of the trolley wire wear measuring device according to the present invention, respectively, and Figures 5a, b, and c are respectively according to the present invention. FIG. 6 is a configuration diagram of an optical system in an embodiment of the trolley wire wear measuring device, where FIG. 6 a is an overall view, FIG. b is an explanatory diagram of a light projecting section, FIG. , d are principle diagrams of conventional optical type trolley wire wear measuring devices, respectively. 1...Trolley wire, 1-1...Sliding surface, 1-2...Side surface, 2...Light source, 3, 5...Lens, 4...Projecting light beam,
6... Light receiver, 7... Hanger, 8... Vehicle roof, 9
...Received light beam, 10... Image pickup tube, 11... Laser beam, 12... Mirror, 13... Rigid support, 13-1
... T-shaped rail, 13-2 ... ear, 14 ... reflected light beam, 15, 20 ... slit plate, 16 ... cylindrical lens, 17 ... projected light flux, 18 ... light band, 18
a... Light band image, 19... Linear image sensor. 2
0a...Slit.

Claims (1)

[Claims] 1. A device for measuring the width of a sliding surface of a trolley wire having a rigid overhead wire structure, which measures an incident angle θ ₁ with respect to the sliding surface.
a light projector that projects a light beam at an angle of 60° to 80° and irradiates the sliding surface with a light band in a direction perpendicular to the trolley wire; receiving light and passing through a portion corresponding to the sliding surface in the image of the light band obtained by the received light;
A trolley wire characterized by comprising a slit for cutting a portion corresponding to a rigid overhead wire structure support other than the sliding surface, and a light receiving section having a light receiving sensor for measuring the length of an image corresponding to the sliding surface. Wear measurement device. 2. The difference between the height of the sliding surface and the lower surface of the trolley wire support of the rigid overhead wire structure is d, and the variation width of the height interval between the sliding surface and the optical system consisting of the light projecting section and the light receiving section is When Δh is the incident angle of the projected light beam with respect to the sliding surface, θ ₁ is the incident angle of the projected light beam with respect to the sliding surface, then the width B of the projected light beam in the vertical cross section in the trolley wire direction is determined by the conditional expression; Δh≦Bsinθ ₁ <d. 2. The trolley wire wear measuring device according to claim 1, wherein the light projecting section has a slit for projecting light that can be set to a certain value.