JP2000062612A - Switch monitoring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a switch monitoring device which can calculate the travel position of the operation rod of an electric switch accurately. SOLUTION: This device is composed of a memory means for memorizing a current/number of rotation characteristic showing the relation between the current of the motor for driving an electric switch and the number of rotation of the motor, a current detection means for detecting the drive current of the motor for driving the electric switch and a calculation means for calculating the position of the operation rod of the electric switch from the detected drive current value and the memorized current/number of rotation characteristic.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a switch monitoring apparatus for monitoring an electric switch on a railway, and more particularly, to driving of an electric switch. The present invention relates to a device capable of detecting an electric current to accurately calculate a position of an operation can of an electric pointing machine. 2. Description of the Related Art Conventionally, as this type of a switch monitoring apparatus, for example, as disclosed in Japanese Patent Application Laid-Open No. 2-197460, a current of a motor for driving an electric switch is detected. Then, it has been proposed to monitor the operation state of the electric switch based on the detected value. [0003] In the switch monitoring apparatus according to this proposal, since the drive motor of the electric switch is usually constituted by a 100-volt capacitor-start single-phase induction motor, the drive current of the motor is controlled to a predetermined value. Due to the increase, the abnormality of the load applied to the electric switch is detected, and the operation state of the electric switch is monitored. [0004] By the way, when the torque of the electric point machine is determined from the drive current value of the motor for driving the electric point machine, and the electric point machine is to be monitored. ,
Knowing where the load is increasing in the stroke of the operating rod is effective in maintaining the electric switch. However, the electric switch has no sensor for detecting the stroke position of the operating can, and thus cannot detect the stroke position of the operating can. [0005] As a method of detecting the stroke position of the operation can of the electric pointer, a detection method based on the travel time of the operation can be considered. This will be described with reference to the schematic configuration diagram of the electric switch shown in FIG. 5. The conversion roller R is connected to a start point of the conversion roller at a center point O through a link (not shown) as shown by a dashed line. From point A (hereinafter, point A) to the end point of the conversion roller (hereinafter, point F) (when the conversion roller R rotates counterclockwise, point F is the start point of the conversion roller, and point A is the end point of the conversion roller. ) So as to be able to make a circular motion in a reciprocating manner. That is, the conversion roller R
Is configured to be rotatable via a reduction gear mechanism W by rotation of a motor M for driving an electric point machine. When the conversion roller R rotates from the point A to the operation start point B of the cam bar C1 (hereinafter referred to as point B. When the conversion roller R rotates counterclockwise, the point B becomes the operation end point of the cam bar C1. ), The cam bar C1 has an arc shape centered on the center point O, so that there is substantially no load from point A to point B. While the transfer roller R moves from point B to point C, the cam bar C1 is moved. From point A to point C, it moves at time t1. When the conversion roller R is rotated counterclockwise from the point C to the operation end point D (hereinafter referred to as the point D), the point D becomes the operation start conversion point.
When the movement is performed, the operation can 10a is moved. The movement amount of the operation can 10a from the point c to the point d is the stroke S of the operation can 10a. In addition, due to the movement of the operation can 10a, the lock can 10b is also moved with the movement of the tong rail (not shown). The cam bar C2 is moved while the changeover roller R moves from the point D to the point E, and the motor M is turned off when the cam bar C2 moves to the point E. Thereafter, the conversion roller R moves to the point by inertia. And
Assume that it takes time t2 to move from point d to point e. Further, assuming that the time required for the movement from the point A to the point E is T, the time required for the movement of the operation can 10a is T-t1-
It is obtained as t2. Assuming that the angle from the point c to the point d about the center point O is α, the position θt of the conversion roller R after t seconds from the point a can be obtained by the following equation. θt = {α / (T−t1−t2)} × (t−t1) + θ0 where θ0 is the angle from point A to point C about the center point O. The method of detecting the travel position of the moving can based on time includes the required time t1 from point a to point c and the required time t from point d to point e.
2 is assumed in advance, so that the required time t
If 1 or the like fluctuates, there is a problem that an error occurs in the calculated detection position of the motion can. The present invention has been made in order to solve the above-mentioned drawbacks, and an object of the present invention is to provide a monitoring device for a turning machine capable of accurately calculating a stroke position of an operating can. It is in. According to the present invention, there is provided a switch monitoring apparatus according to the present invention, wherein a current of a motor for driving an electric switch, a rotation speed of the motor, and the like are provided. Storage means for storing a current / rotational speed characteristic indicating the relationship of: a current detection means for detecting a drive current of a motor for driving the electric pointing machine; and a current / current value stored with the detected drive current value. Calculating means for calculating the position of the operating point of the electric pointing machine from the rotational speed characteristics. Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram of a switch monitoring apparatus according to one embodiment. [0014] The motor M for driving the electric pointing machine is similar to a driving motor provided in a known electric pointing machine.
It is composed of a capacitor-activated single-phase induction motor, and is used as a drive source for operating an operation rod (not shown) of the electric pointer 1 to convert a tong rail (not shown). The motor M is configured to be driven by receiving power from a power supply section 2 composed of a 100 volt AC power supply, and the driving power supply is detected by an ammeter 3 serving as current detecting means of the present invention. It is configured to be. In FIG. 1, reference numeral 4 denotes a processing unit, which is an analog / digital (A / D) conversion circuit 4a for converting an analog current value detected by the ammeter 3 into a digital current value, and a digital conversion. C that calculates the stroke position of the operation of the electric pointing machine 1 (see 10a in FIG. 5) based on the obtained current value.
And a processing circuit 4b centered on the PU. Note that the processing unit 4 serves as a calculating unit of the present invention. Next, the monitoring control operation of the electric switch 1 will be described with reference to FIG. In FIG. 2, the conversion time, the motor current (A), and the motor rotation speed (rpm) are data indicating characteristics when the electric pointing machine 1 is converted. That is, this data is stored in a processing circuit (CP
U) From the start of the conversion (t0) to the end of the conversion (tn) (tn) in FIG. 5 using the motor current / rotation speed data stored in the memory (not shown) of 4b. This is data obtained by calculating the motor rotation speed (rpm) with respect to the motor current (A) at the time of sampling for every predetermined time (Δt). The travel position of the conversion roller R, that is, the travel position of the operating rod 10a is obtained by dividing the total amount of rotation for each Δt time by the gear ratio (reduction ratio) r of the gear mechanism W. It is also possible to calculate based on the point a, but since the position of the conversion roller R at the start of conversion is not always constant, it is calculated back from the position after the end of conversion (see point e in FIG. 5). (See * 4 in FIG. 2). The position (point E) after the end of the conversion is substantially constant at a position where the power of the motor M is turned off by a switch (not shown), and therefore, the movement of the operating rod 10a is based on this position (point E). The travel position is calculated. That is, the travel position of the operation can 10a is
The total amount of rotation for each Δt time with respect to point e is represented by the gear ratio r
Divided by In the above example, the case where the conversion roller R rotates clockwise from the point A to the point A has been described. However, when the conversion roller R rotates counterclockwise from the point A to the point A. Is similarly obtained. By the way, 1 used in the electric switch 1
As shown in FIG. 3 (a), the current / rotational speed characteristics of a 00 volt capacitor-start single-phase induction motor indicate that even with the same type of motor, each motor (FIG. 3 (a) shows an example of three motors). Is slightly different from product to product. As shown in FIG. 3B, the current / rotational speed characteristics shown in FIG.
(The portion from the motor current 0 to the left end of the characteristic line) is removed to create the current / rotational speed characteristics, the characteristics of each motor are almost the same. Therefore, if the rotational speed with respect to the increase current from the no-load current shown in FIG. 4 is obtained using the corrected data of the electric / rotational speed characteristics, analysis with even less error can be performed. As a specific method, the following method can be considered. (1) No-load current of the motor M in advance, or
A current almost equal to the no-load current is measured and stored, and the current is subtracted from the operating current automatically measured during the operation of the electric point machine 1, and the motor is obtained from the relationship between the increased current and the rotation speed of the motor. Find the number of rotations. (2) During the operation of the electric switch 1, there is a time during which almost no load is applied, and the current at that time is generally the smallest current. If the current is automatically set to the no-load current, there is no need to measure the no-load current in advance (see FIG. 4) (except when the conversion starts and when the conversion ends). (3) The minimum value of the operating current may be smaller than the no-load current of the motor depending on the type of the branch operated by the electric switch 1, so the timing for measuring the no-load current is set in advance. And the no-load current is measured at that timing. (4) As shown in FIG. 2A, a plurality of data are prepared, and it is determined which characteristic should be used from the no-load current of the motor M of the electric point machine 1 to be monitored. , The number of rotations is calculated. Data can be selected by measuring the no-load current in advance and setting which data to use, or automatically determining which data to use by calculating the no-load current from the automatically measured operating current. There is a way to judge. (5) The rotational speed is calculated by correcting the basic data based on the difference between the no-load current of the basic data prepared in advance and the actually measured no-load current. As the correction method, there is a method of measuring the no-load current in advance and setting how much to correct, and automatically measuring the amount of no-load current from the operating current and automatically correcting how much. There is a way to judge. (6) The rotational speed is calculated by correcting the operating current based on the difference between the no-load current of the basic data prepared in advance and the no-load current actually measured. As a method of correction, a method of measuring no-load current in advance and setting how much to correct,
There is a method of obtaining a no-load current from the automatically measured operating current and automatically determining how much to correct. The switch monitoring apparatus according to the present invention stores a current / rotation speed characteristic indicating the relationship between the current of the motor driving the electric switch and the rotation speed of the motor. Storage means; current detection means for detecting a drive current of a motor for driving the electric pointing machine; and operation of the electric pointing machine based on the detected driving current value and the stored current / rotation speed characteristics. Since it comprises the calculating means for calculating the position of the can, it is possible to calculate and monitor an accurate stroke position of the operation can with little error.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic configuration diagram of a switch monitoring apparatus according to an embodiment of the present invention. FIG. 2 is an explanatory diagram for calculating a stroke position of an operation lever. FIG. 3 is a current-rotation speed characteristic diagram. FIG. 4 is a current-time curve diagram. FIG. 5 is a schematic configuration diagram of an electric pointing machine. [Description of Signs] 1 Electric Pointing Machine 2 Power Supply Unit 3 Ammeter 4 Processing Unit 4a Analog / Digital Conversion Circuit 4b Processing Circuit M Motor

Claims (1)

Claims: 1. A storage means for storing a current / rotational speed characteristic indicating a relationship between a current of a motor for driving an electric pointing machine and a rotation speed of the motor; Current detecting means for detecting a drive current of a motor for driving the machine; calculating means for calculating a position of an operating point of the electric pointing machine from the detected drive current value and a stored current / rotational speed characteristic; A point monitoring device, comprising: