CN103708353A - Method for determining brake transient load position of crane (brake slip amount detection) - Google Patents

Method for determining brake transient load position of crane (brake slip amount detection) Download PDF

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Publication number
CN103708353A
CN103708353A CN201410013107.XA CN201410013107A CN103708353A CN 103708353 A CN103708353 A CN 103708353A CN 201410013107 A CN201410013107 A CN 201410013107A CN 103708353 A CN103708353 A CN 103708353A
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brake
braking
speed
crane
detecting device
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CN103708353B (en
Inventor
王晓俊
王祎
季亮
袁易之
李超
周杏鹏
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NANJING NEW THINKING AUTOMATION TECHNOLOGY Co Ltd
Southeast University
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NANJING NEW THINKING AUTOMATION TECHNOLOGY Co Ltd
Southeast University
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Abstract

The invention discloses a method for determining a brake transient load position of a crane (brake slip amount detection). The method is characterized by comprising the following steps of receiving a moment of brake information transmitted by a brake signal sensitive circuit through a short-distance wireless communication way by a brake slip-amount detection device, subtracting the communication transmission and software processing delay time and the brake signal detection circuit hardware delay time to obtain a real brake transient moment of the crane, and accurately measuring a brake transient position of a load in the movement process through a dynamic positioning algorithm of the brake transient load position. By adopting the method, the problem of the traditional crane brake slip-amount detection method that the timing of the real brake transient moment is severely delayed can be solved, and the brake slip-amount detection consistency can be improved; the problem that the error in measuring the brake transient down load position of the crane is large in the dynamic measurement process based on an ultrasonic ranging sensor can be solved, and the automatic high-precision measurement of the brake slip-amount detection brake transient down load position can be realized.

Description

Hoisting crane (braking glide quantity detection) braking momentary duty method for determining position
Technical field
The present invention relates to a kind of hoisting crane (braking glide quantity detection) braking momentary duty method for determining position, particularly a kind of hoisting crane (braking glide quantity detection) braking momentary duty position measurement and definite method based on ultrasonic measuring distance technology.
Background technology
It is to being suspended on the rated load of uniform descent on hoisting crane, sending brake command that crane brake downslide amount detects, and measures the distance that crane brake after load slides due to own wt.Note braking momentary duty height
Figure 801541DEST_PATH_IMAGE001
, the final height of load after having braked
Figure 656364DEST_PATH_IMAGE002
, braking glide quantity is
Figure 436101DEST_PATH_IMAGE003
.Braking glide quantity is crossed the safety that conference directly has influence on field man and equipment, so braking glide quantity is an important indicator weighing hoisting crane performance, is also that constitutional law regular inspection is surveyed the important content of department to the check of elevator machinery performance constrained.Due to position be to measure while remaining static after crane brake completes, no matter by distance measuring sensor or manual measurement method, all can obtain information accurately, and braking momentary duty position
Figure 832633DEST_PATH_IMAGE005
to carry out dynamic measurement in Crane Load decline process, because brake slide displacement is less than 20mm conventionally, therefore to braking momentary duty position
Figure 592779DEST_PATH_IMAGE005
survey precision require very high, when
Figure 859812DEST_PATH_IMAGE006
measurement constantly lag behind when larger and uncertain with reality braking initial time, will directly cause braking momentary duty height
Figure 245663DEST_PATH_IMAGE007
result of a measurement has larger error.
Existing crane brake downslide amount braking momentary duty location determining method has several as follows:
1 range estimation: inspector's manipulating crane controller, in load uniform descent process, press stop button, while estimating from braking, be carved into load and stop glided distance.The accuracy that the method is measured depends on inspector's sense organ judgement, and accuracy rate is low.
The 2 weight methods that adopt travel switch to control: pull travel switch to make hoisting crane send speed-slackening signal after weightlessness by the counterweight declining with load, then measure counterweight position to the distance of the dead load of having braked, i.e. distance of glide.Owing to pulling travel switch to hoist power-cut from counterweight, always there is a time delay, the distance of glide that causes detection to obtain is greater than actual braking glide quantity, and different power-down control device, and this deviation is different.
Said method need to carry out machinery and controller circuitry transformation to field apparatus, needs manual detection, has a strong impact on work efficiency, is difficult to realize the demand that automation detects simultaneously.
For improving the intelligent degree of measuring, prior art also has the crane brake downslide amount online test method based on pressure sensor and non-contact distance-measurement sensor, the method installs pressure sensor additional on brake controller, obtain brake command, because of pressure sensor impression is the pressure signal of manually pressing, speed-slackening signal detects and has shake, and its time delay is uncertain, is difficult to meet for the needed timing accuracy requirement of braking glide quantity braking momentary duty position probing; Meanwhile, the braking initial time that pressure sensor sends
Figure 914542DEST_PATH_IMAGE008
, and actual electric braking is constantly
Figure 845589DEST_PATH_IMAGE009
but be that hoisting crane electric control cabinet receives after the brake command of brake controller, cut off the power supply of hoisting crane corresponding motor, the initial time that load power-off is slided,
Figure 599918DEST_PATH_IMAGE010
to lag behind
Figure 523881DEST_PATH_IMAGE011
; For the system that adopts communication, also exist crane brake signal sensitive circuit to send braking information and process time delay to communication transfer time delay and the software of crane brake downslide amount detecting device
Figure 47266DEST_PATH_IMAGE012
, these are that existing measuring system braking momentary duty errors in position measurement is large, the not high major reason of measurement conformability.
Wherein, the braking glide quantity detection scheme combining with noncontact rang sensor based on speed-slackening signal sensitive circuit has become very popular measurement pattern, comprise that the measurement scheme based on laser range sensor must install reflecting curtain additional in load bottom or side, machine rebuilding is more complicated, and ultrasonic distance-measuring sensor is because of its taper transmitting, less demanding to reflecting surface, without measuring load transformation, but to ultrasonic distance-measuring sensor measurement scheme, if received after brake command at brake slide amount detecting device, triggering ultrasonic distance-measuring sensor carries out detection and can produce larger error again, as the load of the uniform descent with 2m/min, when dropping to brake slide amount detecting device, it in succession sends speed-slackening signal when about 1.5m, brake slide amount detecting device receives after brake command, triggering ultrasonic distance-measuring sensor detects, to produce about 4.4ms time delay, cause braking momentary duty positional error to be about 8.8mm, seriously reduced survey precision, although this causes the present scheme checking system based on ultrasonic distance-measuring sensor to build convenient and efficient, but because precision is low, be difficult to practicality.
Summary of the invention
The object of this invention is to provide and a kind ofly for crane brake downslide amount, detect, braking momentary duty method for determining position based on speed-slackening signal sensitive circuit and ultrasonic distance-measuring sensor, the timing that solves the braking instantaneous moment of conventional hoist brake slide quantity measuring method existence has the problem of larger random delay and the large problem of braking momentary duty errors in position measurement.
For achieving the above object, hoisting crane of the present invention (braking glide quantity detection) braking momentary duty method for determining position is, first speed-slackening signal sensitive circuit is by the current transformer monitoring crane brake power cable line current being attached thereto, identification speed-slackening signal, by short-distance wireless communication mode, to brake slide amount detecting device, send braking information, brake slide amount detecting device obtains crane brake instantaneous moment by braking instantaneous accurate timing method; Again by the braking instantaneous position of kinematic Positioning Algorithm Measurement accuracy load in motion process of braking momentary duty position.
The instantaneous accurate timing method of described braking is by brake slide amount detecting device, to be received the moment of braking start information
Figure 414793DEST_PATH_IMAGE013
deduct wireless communication transmissions and software and process time delay
Figure 656419DEST_PATH_IMAGE014
with the time delay of speed-slackening signal testing circuit hardware
Figure 118493DEST_PATH_IMAGE015
, obtain actual braking initial time
Figure 761964DEST_PATH_IMAGE016
.Wherein, communications and software are processed time delay
Figure 34814DEST_PATH_IMAGE017
on-line Measuring Method be, in system initialisation phase, speed-slackening signal sensitive circuit and brake slide amount detecting device are set up point-to-point communication channel, by speed-slackening signal sensitive circuit to brake slide amount detecting device transmission delay test command, brake slide amount detecting device receives after order immediately to the order of speed-slackening signal sensitive circuit loopback delay testing, so continuous circulation sends n time, and brake slide amount detecting device is measured n circle transmission institute elapsed time
Figure 763735DEST_PATH_IMAGE018
, by the communications and the software that calculate between speed-slackening signal sensitive circuit and brake slide amount detecting device are processed time delay
Figure 527478DEST_PATH_IMAGE020
.
Described braking momentary duty position kinematic Positioning Algorithm is, the ultrasonic propagation time sequence of load " uniform descent-braking-stopping " process gathering with measurement period T according to ultrasonic distance-measuring sensor is chosen the interval travel time sequence of uniform descent process t d( nT s) carry out linear fit, obtain t ddecline constantly with load
Figure 236808DEST_PATH_IMAGE021
and load descending speed v 1function
Figure 187446DEST_PATH_IMAGE022
, then to the hypracoustic velocity of sound carry out temperature compensating and
Figure 256902DEST_PATH_IMAGE023
the Doppler effect compensation causing obtains the velocity of sound accurately
Figure 609386DEST_PATH_IMAGE024
, construct the at the uniform velocity kinematic function of the load position-time of process
Figure 489617DEST_PATH_IMAGE025
, when
Figure 927552DEST_PATH_IMAGE026
time calculate braking momentary duty position.
The beneficial effect that the present invention obtains is: the timing that (1) has solved the braking instantaneous moment that conventional hoist brake slide quantity measuring method exists has the problem of larger random delay, has improved the conformability that braking glide quantity detects; (2) solved in the dynamic measurement process based on ultrasonic distance-measuring sensor, the large problem of braking momentary duty errors in position measurement, has realized braking glide quantity and has detected the automatic, high precision measurement of braking momentary duty position.
Accompanying drawing explanation
Fig. 1 is the system architecture diagram that a kind of crane brake downslide amount of the present invention detects;
Fig. 2 is crane brake momentary duty location determining method diagram of circuit of the present invention;
Fig. 3 is signal time delay on-line measurement diagram of circuit of the present invention;
Fig. 4 is that the present invention brakes instantaneous descending load position dynamicpositioning computing block diagram;
Fig. 5 is that the present invention brakes instantaneous descending load position and determines method flow diagram;
Wherein: 1, split core type current transformer, 2, speed-slackening signal sensitive circuit, 3, brake slide amount detecting device, 4, ultrasonic distance-measuring sensor.
 
The specific embodiment
Below in conjunction with accompanying drawing, technical scheme of the present invention is described in further details:
Embodiments of the invention as shown in Figure 1, Figure 2, shown in Fig. 3, Fig. 4 and Fig. 5, for a kind of, for hoisting crane (braking glide quantity detection), brake momentary duty method for determining position, first speed-slackening signal sensitive circuit 2 is by the current transformer monitoring crane brake power cable line current being attached thereto, identification speed-slackening signal, by short-distance wireless communication mode, to brake slide amount detecting device 3, send braking information, brake slide amount detecting device 3 obtains crane brake instantaneous moment by braking instantaneous accurate timing method; Again by the braking instantaneous position of kinematic Positioning Algorithm Measurement accuracy load in motion process of braking momentary duty position.
In system initialisation phase, speed-slackening signal sensitive circuit 2 is set up point-to-point communication channel with brake slide amount detecting device 3, by speed-slackening signal sensitive circuit 2 to brake slide amount detecting device 3 transmission delay test commands, brake slide amount detecting device 3 receives after order immediately to the 2 loopback delay testing orders of speed-slackening signal sensitive circuit, so continuous circulation sends n time, by brake slide amount detecting device 3, measures n circle transmission institute elapsed time
Figure 540979DEST_PATH_IMAGE027
, by the communications and the software that calculate between speed-slackening signal sensitive circuit 2 and brake slide amount detecting device 3 are processed time delay
Figure 64681DEST_PATH_IMAGE029
.
When brake slide amount detecting device 3 receives after braking start information, by current time
Figure 989912DEST_PATH_IMAGE030
deduct communications and software and process time delay with the time delay of speed-slackening signal testing circuit hardware
Figure 462668DEST_PATH_IMAGE032
, obtain actual braking initial time
Figure 747018DEST_PATH_IMAGE033
.
The ultrasonic propagation time sequence of load " uniform descent-braking-stopping " process gathering with measurement period T according to ultrasonic distance-measuring sensor 4 again, chooses the interval travel time sequence of uniform descent process t d( nT s) carry out linear fit, obtain t ddecline constantly with load
Figure 97228DEST_PATH_IMAGE034
and load descending speed v 1function
Figure 125227DEST_PATH_IMAGE035
, then to the hypracoustic velocity of sound carry out temperature compensating and
Figure 493761DEST_PATH_IMAGE036
the Doppler effect compensation causing obtains the velocity of sound accurately , construct the at the uniform velocity kinematic function of the load position-time of process
Figure 520939DEST_PATH_IMAGE038
, when time calculate braking momentary duty position.
The specific works mode of the present embodiment is as follows:
(1) split core type current transformer 1 pincer is installed in to the electric wireline place of crane brake motor;
(2) speed-slackening signal sensitive circuit 2 is set up point-to-point communication channel with brake slide amount detecting device 3; Speed-slackening signal sensitive circuit 2 is to brake slide amount detecting device 3 transmission delay test commands; Brake slide amount detecting device 3 receives the backward speed-slackening signal sensitive circuit 2 loopback delay testing orders of order, and so circulation sends n time, by brake slide amount detecting device 3, measures n circle transmission institute elapsed time
Figure 575669DEST_PATH_IMAGE040
, by
Figure 936243DEST_PATH_IMAGE041
the communications and the software that calculate between speed-slackening signal sensitive circuit 2 and brake slide amount detecting device 3 are processed time delay
Figure 261045DEST_PATH_IMAGE042
.
(3) start super sonic real time distance module, with a fixed repetition period
Figure 630847DEST_PATH_IMAGE043
real-time Collection load position, obtains the time series of ultrasonic probe to the interval travel time of load reflecting surface
Figure 708393DEST_PATH_IMAGE044
;
(4) speed-slackening signal sensitive circuit 2 detects the current transformer output signal being attached thereto, and identification speed-slackening signal, sends braking start information by wired or wireless mode to brake slide amount detecting device 3;
(5) brake slide amount detecting device 3 receives after braking start information, by current time
Figure 443131DEST_PATH_IMAGE045
deduct communications and software and process time delay
Figure 51967DEST_PATH_IMAGE029
with the time delay of speed-slackening signal testing circuit hardware
Figure 412410DEST_PATH_IMAGE046
, obtain actual braking initial time
Figure 423091DEST_PATH_IMAGE047
(6) the interval travel time sequence segmentation that 3 pairs of ultrasonic distance-measuring sensors 4 of brake slide amount detecting device record in real time, is chosen at the time series in the interval travel time of load uniform descent process
Figure 391047DEST_PATH_IMAGE048
, by method of least square, carry out linear fit, obtain the interval travel time
Figure 424862DEST_PATH_IMAGE049
decline constantly with load
Figure 136466DEST_PATH_IMAGE050
function
Figure 188605DEST_PATH_IMAGE051
;
(7) ambient temperature obtaining according to temperature sensor measurement, looks into the relation table of the velocity of sound and temperature or obtains the velocity of sound under Current Temperatures according to the velocity of sound-temperature funtion relation
Figure 327462DEST_PATH_IMAGE052
; By Doppler's formula, calculate the dynamic velocity of sound in dynamic decline process again
Figure 848573DEST_PATH_IMAGE053
;
(8) set up the load function of the position-time in uniform descent process:
Figure 98289DEST_PATH_IMAGE054
; Order
Figure 270513DEST_PATH_IMAGE055
, calculate braking initial position.
The present embodiment adopts the useful technique effect of above technical scheme to be:
(1) timing that has solved the braking instantaneous moment that conventional hoist brake slide quantity measuring method exists has the problem of larger random delay, has improved the conformability that braking glide quantity detects;
(2) solved in the dynamic measurement process based on ultrasonic distance-measuring sensor, the large problem of braking momentary duty errors in position measurement, has realized braking glide quantity and has detected the automatic, high precision measurement of braking momentary duty position.

Claims (3)

1. hoisting crane (braking glide quantity detection) braking momentary duty method for determining position, is characterized in that: brake slide amount detecting device receives the moment of the braking information that speed-slackening signal sensitive circuit sends by short-distance wireless communication mode
Figure 51785DEST_PATH_IMAGE002
, deduct communications and software and process time delay
Figure 968925DEST_PATH_IMAGE004
with the time delay of speed-slackening signal testing circuit hardware , obtain the instantaneous real-time moment of crane brake
Figure 707653DEST_PATH_IMAGE008
, and by the braking instantaneous position of kinematic Positioning Algorithm Measurement accuracy load in motion process of braking momentary duty position.
2. hoisting crane according to claim 1 (braking glide quantity detection) braking momentary duty method for determining position, is characterized in that: described communications and software are processed time delay
Figure 584342DEST_PATH_IMAGE010
method of measurement be, in system initialisation phase, speed-slackening signal sensitive circuit and brake slide amount detecting device are set up point-to-point communication channel, by speed-slackening signal sensitive circuit unit to brake slide amount detecting device transmission delay test command, brake slide amount detecting device receives after order immediately to the order of speed-slackening signal sensitive circuit loopback delay testing, so continuous circulation sends n time, by brake slide amount detecting device, measures n circle transmission institute elapsed time
Figure 406805DEST_PATH_IMAGE012
, by
Figure 736155DEST_PATH_IMAGE014
the communications and the software that calculate between speed-slackening signal sensitive circuit and brake slide amount detecting device are processed time delay
Figure 935055DEST_PATH_IMAGE016
.
3. hoisting crane according to claim 1 and 2 (braking glide quantity detection) is braked momentary duty method for determining position, it is characterized in that: described braking momentary duty position kinematic Positioning Algorithm is, the ultrasonic propagation time sequence of load " uniform descent-braking-stopping " process gathering with measurement period T according to ultrasonic distance-measuring sensor, chooses the interval travel time sequence of uniform descent process t d( nT s) carry out linear fit, obtain t ddecline constantly with load
Figure 666251DEST_PATH_IMAGE018
and load descending speed v 1function
Figure 659615DEST_PATH_IMAGE020
, then to the hypracoustic velocity of sound carry out temperature compensating and
Figure 971866DEST_PATH_IMAGE022
the Doppler effect compensation causing obtains the velocity of sound accurately , construct the at the uniform velocity kinematic function of the load position-time of process
Figure 232264DEST_PATH_IMAGE026
, when
Figure 724425DEST_PATH_IMAGE028
time calculate braking momentary duty position.
CN201410013107.XA 2014-01-13 2014-01-13 Crane brake downslide amount detects braking momentary duty method for determining position Expired - Fee Related CN103708353B (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103979420A (en) * 2014-04-29 2014-08-13 南通中远船务自动化有限公司 Power-off brake buffer device for large-scale gantry crane
CN105486238A (en) * 2015-12-25 2016-04-13 北京起重运输机械设计研究院 Method and system for measuring brake downslide amount of lifting mechanism
CN113353803A (en) * 2021-06-30 2021-09-07 日照钢铁控股集团有限公司 Automatic accurate and rapid positioning control method for cyclone well travelling crane

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Publication number Priority date Publication date Assignee Title
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CN201052955Y (en) * 2007-06-11 2008-04-30 中国第一冶金建设有限责任公司 Braking apparatus for crawler crane
CN201952113U (en) * 2010-12-09 2011-08-31 江苏省特种设备安全监督检验研究院 Braking gliding amount testing instrument for cranes
CN101875477B (en) * 2009-12-04 2012-05-09 哈尔滨工业大学 Crane with brake failure protection device and brake failure protection method
CN202562441U (en) * 2012-05-25 2012-11-28 孙富亮 Detecting device for braking glide quantity of crane
CN103245316A (en) * 2013-05-07 2013-08-14 福建省特种设备检验研究院 Crane braking gliding amount detecting system

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Publication number Priority date Publication date Assignee Title
CN101012044A (en) * 2007-02-09 2007-08-08 上海港机重工有限公司 Recording device and method for hoisting machinery operating state
CN201052955Y (en) * 2007-06-11 2008-04-30 中国第一冶金建设有限责任公司 Braking apparatus for crawler crane
CN101875477B (en) * 2009-12-04 2012-05-09 哈尔滨工业大学 Crane with brake failure protection device and brake failure protection method
CN201952113U (en) * 2010-12-09 2011-08-31 江苏省特种设备安全监督检验研究院 Braking gliding amount testing instrument for cranes
CN202562441U (en) * 2012-05-25 2012-11-28 孙富亮 Detecting device for braking glide quantity of crane
CN103245316A (en) * 2013-05-07 2013-08-14 福建省特种设备检验研究院 Crane braking gliding amount detecting system

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103979420A (en) * 2014-04-29 2014-08-13 南通中远船务自动化有限公司 Power-off brake buffer device for large-scale gantry crane
CN103979420B (en) * 2014-04-29 2015-11-11 南通中远船务自动化有限公司 Large-sized gantry crane dead electricity brake buffer unit
CN105486238A (en) * 2015-12-25 2016-04-13 北京起重运输机械设计研究院 Method and system for measuring brake downslide amount of lifting mechanism
CN113353803A (en) * 2021-06-30 2021-09-07 日照钢铁控股集团有限公司 Automatic accurate and rapid positioning control method for cyclone well travelling crane

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