JP4685803B2 - Elevator brake control device - Google Patents

Description

  The present invention relates to an elevator brake control device that detects an abnormality of a DC electromagnetic brake by an excitation circuit current of a brake electromagnet in a DC electromagnetic brake.

This type of device is a DC electromagnetic brake abnormality detection method that continuously measures the secular change of current during brake operation, and the normal rate of increase in current value from the start of energization to the start of movement of the movable core is normal. Detecting an abnormality by comparing the rising speed at the time (see, for example, Patent Document 1), or detecting the time during which a drop in the excitation current occurs during braking operation, and setting the time in advance to normal and abnormal What detects an abnormality by comparing with the range of the occurrence time of the drop (for example, see Patent Document 2) is known.
Patent No. 2795152 Japanese Patent Laid-Open No. 3-55342

  In the DC electromagnetic brake, when the brake coil is energized to generate electromagnetic force, the lining starts to be attracted from the drum braking surface, and the brake current starts to be distorted. For this reason, in the case of a device configuration in which the current flowing through the plurality of brake coils is detected by one current detection means, there are cases where the current change point does not drop clearly. In addition, even when the gap becomes small, the current drop at the start-up is small and difficult to detect.

  The conventional method of continuously measuring the aging of the current detection method requires high-precision and high-speed current detection means to detect short-term current changes when the gap becomes small, and detects dip. The method also needed to be performed at high speed.

  In addition, if the operating position of the brake check switch is not installed at a position that completely matches the point where the brake current drops, the operating position of the brake check switch differs depending on the individual brake device, so that the normal brake opening / closing operation is performed. However, the current at the time of operation of the brake check switch is different, and the current value or time range that makes each brake abnormal may be different.

  An object of the present invention is to provide an elevator brake control device that detects an abnormality of a DC electromagnetic brake without being affected by current distortion during brake operation or the operation position of a brake check switch without adding a special device. is there.

In order to achieve the above object, in claim 1 of the present application, a brake check switch that is installed in a DC electromagnetic brake and detects an open / close state of the brake, a main control unit that commands opening / closing of the DC electromagnetic brake, and the DC In an elevator brake control device comprising current detecting means for detecting an exciting current flowing in a brake coil of an electromagnetic brake, and a brake circuit for causing an exciting current to flow in the brake coil by the main control means, the elevator brake control device is installed at two left and right positions of the drum Each of the DC electromagnetic brakes, a brake check switch provided for each of the DC electromagnetic brakes, a brake coil for operating each of the DC electromagnetic brakes by being connected to the power supply in parallel and being energized, An electric current detecting the total value of the exciting current flowing through the brake coil. A detection means, a storage means for storing the current value of the normal detected by said current detecting means includes a current value at each of the brake check switch operation and the current value of the stored abnormality In comparison, the shift of the operation timing of the DC electromagnetic brakes installed on the left and right is detected.

  In this claim 1, since the exciting current of the brake coil is discretely detected, there is no need to continuously measure the exciting current, and as a result, the current drop at the time of starting is small and the detection is difficult. The problem that it is necessary to detect current at high speed can be solved.

According to a second aspect of the present invention , the brake check switch is installed in the DC electromagnetic brake and detects the open / close state of the brake, the main control means for commanding the opening / closing of the DC electromagnetic brake, and the brake coil of the DC electromagnetic brake. In an elevator brake control device provided with a current detection means for detecting an excitation current, and a brake circuit for flowing an excitation current to the brake coil by the main control means, the DC electromagnetic brakes installed at two left and right positions of the drum, The sum of the brake check switch provided in each of the DC electromagnetic brakes, the brake coil that is connected to the power source in parallel and energized to operate each of the DC electromagnetic brakes, and the excitation current that flows through each of the brake coils Current detection means for detecting the value, and the current detection means A storage means for storing the current value of the normal that issued, and time measuring means for measuring a time until each of the brake check switch from the brake switching command of the main control unit is operated by the time measuring means Storage means for storing the measured normal time and the normal current value detected by the current detection means, and the brake check switch operation time and current measured by the respective time measurement means The value is compared with the stored normal time and current value, and a deviation in the operation timing of the DC electromagnetic brakes installed on the left and right is detected.

According to the second aspect , more accurate abnormality detection can be performed.

A third aspect of the present invention provides the length of the stroke according to the first or second aspect by linearly approximating a relationship between a stroke of the DC electromagnetic brake and a value of a current flowing through the brake coil when the brake check switch is operated. It is characterized by estimating the thickness.

According to the third aspect , since the stroke of the brake device can be estimated, it is possible to determine what is abnormal (lining wear or contamination) when detecting the abnormality of the brake device.

Further, in claim 4 in claims 1 to 2, wherein, by controlling the braking current to rise slower than the time constant of the brake coil current value at the time of the brake check switch operation, detecting the operating time, measured It is characterized by doing.

According to Claim 4 , since the time constant of the brake coil is not affected by Claims 1 to 2 , the excitation current when the brake check switch is operated can be detected more accurately, so that the change in stroke can be accurately estimated. In addition, since the current change becomes gentle by giving the brake current command slowly over time, high-speed current detection means is not required.

A fifth aspect of the present invention is characterized in that in the first or second aspect of the present invention, communication means for diagnosing the state of the DC electromagnetic brake device and transmitting the secular change or abnormal state to the control center is provided.

According to the fifth aspect , since the abnormality detection is transmitted by the communication means when the abnormality of the brake device is detected, it is possible to prevent the elevator service from being stopped due to the failure of the brake device.

  According to the present invention, it is possible to detect an abnormality of a DC electromagnetic brake without being affected by current distortion during brake operation or the operation position of a brake check switch without adding a special device.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram illustrating a configuration of a brake device (when released) provided with a brake check switch, FIG. 2 is a diagram illustrating a configuration (when sucking) of a brake device provided with a brake check switch, and FIG. 4 is a diagram showing an electric circuit diagram of the brake device, FIG. 5 is a diagram showing an example of brake current response and brake check switch operation timing, and FIG. 6 is a diagram of a DC electromagnetic brake when the lining is worn. FIG. 7 is a diagram showing the relationship between the brake current and the stroke, and FIG. 8 is a diagram showing the relationship between the brake activation current and the stroke when the brake check switch is activated.

  In FIG. 1, a DC electromagnetic brake 15 energizes the drum 2 connected to the motor shaft 1, the brake coils 8a and 8b attached to the cores 7a and 7b, and the brake coils 8a and 8b. Amateurs 5a and 5b sucked by the arms, shoes 4a and 4b that move away from the drum 2 by suction of the amateurs 5a and 5b, linings 3a and 3b attached to the shoes 4a and 4b, and the amateur 5a 5b, springs 6a, 6b for applying a restoring force, and brake check switches 9a, 9b for detecting that the amateurs 5a, 5b are sucked.

  In the example of FIG. 1, the brakes are installed at two places on the left and right, and brake check switches 9a and 9b are provided respectively.

  The direct current electromagnetic brake 15 overcomes the braking force of the springs 6a and 6b by flowing current through the brake coils 8a and 8b, attracts the respective amateurs 5a and 5b, separates the linings 3a and 3b from the drum 2, and It is possible to run.

  When the amateurs 5a and 5b are completely sucked as shown in FIG. 2, the brake check switches 9a and 9b are independently operated by mechanical action. Further, when the car is stopped, the amateurs 5a and 5b are restored by cutting off the current, and the braking force is applied by bringing the linings 3a and 3b into contact with the drum 2.

  In FIG. 3, the current detection means 16 connected to the brake coils 8a and 8b in the DC electromagnetic brake 15, the main control means 12 in the brake controller 11 for taking in the current feedback value from the current detection means 16, An elevator controller 10 that inputs a current command value to the main control means 12, and a switching element 14 that converts the voltage of the power source 13 based on the voltage command value output from the main control means 12 and applies it to the brake coils 8a and 8b. A time measuring means 17 for measuring the operating time from the signals of the brake check switches 9a and 9b, a storage means 18 for storing the operating time and the current value detected by the current detecting means 16, and the operating time and the current value. From the diagnosis means 19 for diagnosing the state of the brake device and the communication means 20 for communicating with the control center 21.

  In FIG. 4, R in the figure is the resistance of the brake circuit, the brake coils 8 a and 8 b are connected in parallel to the power supply 13, and the current detection means 16 is connected in series to the power supply 13.

  Therefore, the current detection means 16 detects the total value of the excitation currents flowing through the brake coils 8a and 8b.

  Note that the current detection means 16 can use a non-contact current sensor using a general Hall element to detect the current by passing the winding through the sensor.

  The solid line in FIG. 5A shows an example of the response of the brake current and the operation timing of the brake check switches 9a and 9b when the DC electromagnetic brake 15 is normal.

With respect to the step-like current command I ^* , the exciting currents of the brake coils 8a and 8b are normally delayed with a time constant caused by the inductance of the brake coils 8a and 8b as shown by the solid line in FIG. Try to follow the current command.

However, when the linings 3a, 3b is started to be aspirated from the braking surface of the drum 2, t current is the strain started as shown in the _first time point in FIG. 5 (a), when the suction is completed to complete the brake check switch 9a, 9b is operated Then, the current increases again to follow the command value.

  At this time, the difference between the operation timings of the two brake check switches 9a and 9b may be caused by a mechanical operation delay such as a slight installation error of the brake check switch of each brake.

The signals of the brake check switches 9a and 9b are inputted to the time measuring means 17 in the brake controller 11, and the brake check switches 9a and 9b are obtained by taking the time difference between the timing and the timing at which the brake opening / closing signal is inputted. Start times t ₁ and t ₂ are obtained and stored in the storage means 18 together with the brake start currents I ₁ and I ₂ at that time.

  6 is a diagram when only the lining 3b is worn in the DC electromagnetic brake 15 of FIG. 1. As shown in FIG. 6, the stroke 22b between the arm 5b and the core 7b of the right brake where the lining 3b is worn is shown in FIG. 3a is longer than the stroke 22a between the left brake amateur 5a and the core 7a.

  Thus, when the stroke 22b becomes longer, the magnetic circuit constant between the armature 5b and the core 7b changes, and as a result, the time constant becomes larger. Therefore, more electromagnetic attractive force is required, and the brake check switch The current flowing through the brake coil 8b during operation becomes larger than that during normal operation, and the time constant increases, so that the rise of the brake current is delayed. Therefore, a larger current is required until the brake is attracted, and the response time of the brake current changes.

The operation time t ′ ₂ of the brake check switch 9b of the right brake with the worn lining 3b is significantly different from the operation time t _{2 in} the normal state, and the operation timing of the brake check switches 9a and 9b is the same as that in FIG. 5 (a). It looks like a dashed line. This stroke 22b becomes longer as described above, is for it takes time to start to suck the armature 5b, is larger than the _second brake activation current I 'brake activation current I at the time ₂ is also normal'.

Thus, when abnormality occurs in the brake device, changes appear in the brake activation currents I ₁ and I ₂ and the operation times t ₁ and t ₂ of the brake check switches 9a and 9b.

  Therefore, the diagnosis unit 19 can detect an abnormality in the brake device by comparing with a predetermined operating time and current value obtained in advance from a design value or a measured value in a normal state, or by monitoring a secular change.

  In order to detect the abnormality of the brake device more accurately, it is only necessary to detect the brake current and the brake check switch operating time by making the brake current command into a ramp shape.

  The solid line in FIG. 5B represents an example of the brake current response in the normal state and the operation timing of the brake check switches 9a and 9b when the brake current command is ramped.

At this time, if the spring constants of the springs 6a and 6b are not changed by using a ramp-like brake current command that rises later than the time constants of the brake coils 8a and 8b, the amateurs 5a and 5b start to be attracted. The distortion of the current generated sometimes is small, and the brake activation currents I _r1 and I _r2 during the operation of the brake check switches 9a and 9b can be detected more accurately than in the case of the stepped brake current command.

  The broken line in FIG. 5B represents an example of the operation timing of the brake current response and the brake check switches 9a and 9b when an abnormality occurs when the brake current command is ramped (lining 3b wear).

At this time, the brake current command is slower than the time constant of the brake coils 8a and 8b, and no more current than necessary flows through the brake coil 8b on the abnormal side. Therefore, the brake activation current I ′ when the brake check switch 9a is activated _r1 is equal to the normal value.

  FIG. 7 is a diagram showing the relationship between the brake current and the stroke. In FIG. 7, the normal relationship is represented by a solid line, and when current is passed through the brake coils 8a and 8b to attract the amateurs 5a and 5b, The armatures 5a and 5b do not move due to the elastic force of the springs 6a and 6b, but begin to move at a certain point, pass through the operating positions of the brake check switches 9a and 9b, and come into contact with the cores 7a and 7b. The relationship between the current and the stroke at the time of release is opposite to that at the time of suction, and has a hysteresis characteristic as shown in FIG.

  The broken line in FIG. 7 shows a case where the stroke becomes long. Since the energy for moving the amateurs 5a and 5b increases, a large amount of current flows. The alternate long and short dash line indicates a case where the stroke is shortened. In contrast to the case where the stroke is lengthened, the brake check switches 9a and 9b are operated with a smaller current.

Therefore, when the brake check switches 9a and 9b are operated, the relationship between the brake starting current and the stroke is as shown in FIG. 8, where the stroke length is l and the current value is i.
l = ai + b
A linear approximation can be made as follows. However, a and b are constants.

  Thus, from the normal brake device, the stroke can be estimated from the measured current value by formulating the relationship between the current value and the stroke when the brake check switch is activated in advance.

  As shown in Fig. 8, the stroke threshold value is set to Xmin to Xmax, so the current value threshold value is also determined to be Imin to Imax, and the current value during brake check switch operation exceeds this range. Sometimes it can be anomaly detection.

  As a result, when the brake current command is stepped, a predetermined operation time in which the operation time of the brake check switches 9a and 9b and the brake activation current at that time are obtained in advance from a design value or a measured value in a normal state. The abnormality of the brake device can be detected by comparing with the current value or monitoring the secular change.

  Further, by making the brake current command into a ramp shape, a more accurate brake activation current can be detected, and the stroke can be estimated from the relationship between the stroke and the brake activation current.

  Diagnosis of these brake devices is performed by the diagnosis means 19 and is transmitted from the communication means 20 to the control center 21 when an abnormality is detected. In addition, it is possible to remotely monitor secular changes by monitoring data even during normal times.

  As a result, it is possible to set an appropriate maintenance cycle for lining replacement and prevent an elevator service stop due to a brake device failure.

It is the figure explaining the structure (at the time of release) of the brake device which installed the brake check switch. It is the figure explaining the structure (at the time of attraction | suction) of the brake device which installed the brake check switch. 1 is an overall configuration diagram of the present invention. It is the figure which showed the electric circuit diagram of the brake device. It is the figure which showed the example of a brake current response and a brake check switch operation timing. It is a figure of a DC electromagnetic brake when the lining is worn. It is the figure which showed the relationship between a brake current and a stroke. It is the figure which showed the relationship between the brake starting current at the time of brake check switch starting, and a stroke.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Motor shaft 2 Drum 3a, 3b Lining 4a, 4b Shoe 5a, 5b Amateur 6a, 6b Spring 7a, 7b Core 8a, 8b Brake coil 9a, 9b Brake check switch 10 Elevator control device 11 Brake controller 12 Main control means 13 Power supply DESCRIPTION OF SYMBOLS 14 Switching element 15 DC electromagnetic brake 16 Current detection means 17 Time measurement means 18 Storage means 19 Diagnosis means 20 Communication means 21 Control center 22a, 22b Stroke length

Claims (5)

A brake check switch installed on the DC electromagnetic brake for detecting the open / close state of the brake, main control means for commanding opening / closing of the DC electromagnetic brake, and current detection for detecting an excitation current flowing in the brake coil of the DC electromagnetic brake And an elevator brake control device comprising a brake circuit for passing an exciting current to the brake coil by the main control means,
The DC electromagnetic brakes installed at two positions on the left and right sides of the drum, the brake check switch provided in each of the DC electromagnetic brakes, and the DC electromagnetic brakes connected to the power supply in parallel and energized. A brake coil that operates, a current detection unit that detects a total value of excitation currents flowing through the respective brake coils, and a storage unit that stores a normal current value detected by the current detection unit. The elevator brake is characterized in that a current value at the time of operation of each of the brake check switches is compared with a stored current value at the time of abnormality to detect a deviation in operation timing of the DC electromagnetic brakes installed on the left and right. Control device. A brake check switch installed on the DC electromagnetic brake for detecting the open / close state of the brake, main control means for commanding opening / closing of the DC electromagnetic brake, and current detection for detecting an excitation current flowing in the brake coil of the DC electromagnetic brake And an elevator brake control device comprising a brake circuit for passing an exciting current to the brake coil by the main control means,
The DC electromagnetic brakes installed at two positions on the left and right sides of the drum, the brake check switch provided for each of the DC electromagnetic brakes, and the DC electromagnetic brakes connected to the power supply in parallel and energized. Brake coil to be operated, current detection means for detecting the total value of the excitation current flowing through each of the brake coils, storage means for storing a current value at normal time detected by the current detection means, and the main control means A time measuring means for measuring the time from when the brake opening / closing command of each of the brake check switches is operated, a normal time measured by the time measuring means, and a normal current value detected by the current detecting means and storage means for storing the bets, the brake check Sui measured by each of said time measuring means Elevator brake, characterized in that compared with the time and the current value of the normal time and the current value during switch operation as being the storage, detects the deviation of the operation timing of the DC electromagnetic brake installed on the left and right Control device. 3. The stroke length is estimated by linearly approximating a relationship between a stroke of the DC electromagnetic brake and a value of a current flowing through the brake coil when the brake check switch is operated. The elevator brake control device described . 3. The elevator according to claim 1 , wherein a current value and an operation time during the operation of the brake check switch are detected and measured by controlling a brake current so as to rise later than a time constant of the brake coil. Brake control device. 3. The elevator brake control device according to claim 1 , further comprising communication means for diagnosing a state of the DC electromagnetic brake device and transmitting a secular change or an abnormal state to the control center .

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