CA1212184A - Rope force measuring means - Google Patents
Rope force measuring meansInfo
- Publication number
- CA1212184A CA1212184A CA000423003A CA423003A CA1212184A CA 1212184 A CA1212184 A CA 1212184A CA 000423003 A CA000423003 A CA 000423003A CA 423003 A CA423003 A CA 423003A CA 1212184 A CA1212184 A CA 1212184A
- Authority
- CA
- Canada
- Prior art keywords
- hoist
- measurement
- signal transmission
- transmission according
- signal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
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- Arrangements For Transmission Of Measured Signals (AREA)
Abstract
ABSTRACT
The invention relates to a device for measuring and signal trans-mission in connection with hoists and elevators. The invention is characterized in that between the rope/ropes and the skip and between the skip or hoist cage (5) and/or the counterbalance (6) there are arranged means (1, 2) measuring the load or tensile force, the output signals of said means being adapted to be supplied to a signal processing device (3), which may be completely or partially positioned on the hoist cage (5) and/or on the counterba-lance (6) and/or positioned outside these (in a control room or in the vicinity thereof), for obtaining different signals for monitoring the load in the various ropes (7, 8), also when the hoist is in motion, said signals being adapted to be transmitted to a stationary monitoring device (26). (Figure 1.)
The invention relates to a device for measuring and signal trans-mission in connection with hoists and elevators. The invention is characterized in that between the rope/ropes and the skip and between the skip or hoist cage (5) and/or the counterbalance (6) there are arranged means (1, 2) measuring the load or tensile force, the output signals of said means being adapted to be supplied to a signal processing device (3), which may be completely or partially positioned on the hoist cage (5) and/or on the counterba-lance (6) and/or positioned outside these (in a control room or in the vicinity thereof), for obtaining different signals for monitoring the load in the various ropes (7, 8), also when the hoist is in motion, said signals being adapted to be transmitted to a stationary monitoring device (26). (Figure 1.)
Description
I
The present invention relates to a device for measurement and for signal transmission in connection with hoists and elevators.
Both from the point of view of security and operation, it is of great interest to be able to monitor the condition of ropes in hoists and elevators and, in the case of friction hoists t also the condition of the friction slots which are located around the periphery of the driving pulley.
There are certain devices at the ropes which are able, at least during a downtime to measure the rope condition, but it is more difficult to arrange such monitoring also when the hoist is in motion.
The invention aims to provide a solution to the above-mentio~ed problems and other problems associated there-with. For that purpose, the present invention proposes advice for measurement and signal transmission in a hoist or elevator including a skip/hoist wage, characterized in that between a rope or ropes of the hoist or elevator and the skip hoist cage and/or a counterbalance there are arranged force measuring means delivering output signals which are adapted to be supplied to a signal processing device for obtaining different signals for monitoring a load in the rope or in the different ropes, also in thy case ox a hoist or elevator in motion, which signals are adapted to be transmitted to a monitoring device which is stationarily mounted in relation to the skip/hoist cage.
I
Lowe By such an arrangement a continuous, possibly multiplexed monitoring of the rope condition can be obtained, also in the case of hoists in motion.
The objects, advantages and other features of the present invention will become more apparent from the lot-lowing non-restrictive description of a preferred embodiment thereof, made in connection with the accompanying drawings, in which:
Figure l shows an explanatory sketch of a mine lo hoist according to the invention;
Figure 2 shows a link in hoist/elevator ropes;
Figure 3 shows the electrical system for the invention;
Figure 4 which is disposed on the same sheet of formal drawings as Figures 1 and 2, is an example of the application of a load or tensile force measuring means; and Figure 5 is an alternative mine hoist.
Figure l shows a mine hoist, comprising a drum or driving pulley 4, over which one or several ropes run.
Figure l is a friction hoist and the intention is also to measure the condition of the friction slots which are to be found around the periphery of the pulley 4. The hoist also comprises a hoist cage/skip 5 and a counterbalance 6 as well as ropes 7, 8. Alternatively, the counterbalance 6 can be replaced by a second hoist cage or a second skip It is of great interest to monitor the condition of the ropes 7, 8 and, in case of a friction hoist, also the condition of the friction slots around the periphery of the driving pulley.
A system consisting of rope force measuring devices l, 2 is located between the ropes and the hoist cage 5 and between the ropes and the counterbalance 6, respectively, and the output signals from these devices l, 2 are processed and transmitted to a control equipment 3, which can be employed for a plurality of purposes according to the US invention.
I.
The present invention relates to a device for measurement and for signal transmission in connection with hoists and elevators.
Both from the point of view of security and operation, it is of great interest to be able to monitor the condition of ropes in hoists and elevators and, in the case of friction hoists t also the condition of the friction slots which are located around the periphery of the driving pulley.
There are certain devices at the ropes which are able, at least during a downtime to measure the rope condition, but it is more difficult to arrange such monitoring also when the hoist is in motion.
The invention aims to provide a solution to the above-mentio~ed problems and other problems associated there-with. For that purpose, the present invention proposes advice for measurement and signal transmission in a hoist or elevator including a skip/hoist wage, characterized in that between a rope or ropes of the hoist or elevator and the skip hoist cage and/or a counterbalance there are arranged force measuring means delivering output signals which are adapted to be supplied to a signal processing device for obtaining different signals for monitoring a load in the rope or in the different ropes, also in thy case ox a hoist or elevator in motion, which signals are adapted to be transmitted to a monitoring device which is stationarily mounted in relation to the skip/hoist cage.
I
Lowe By such an arrangement a continuous, possibly multiplexed monitoring of the rope condition can be obtained, also in the case of hoists in motion.
The objects, advantages and other features of the present invention will become more apparent from the lot-lowing non-restrictive description of a preferred embodiment thereof, made in connection with the accompanying drawings, in which:
Figure l shows an explanatory sketch of a mine lo hoist according to the invention;
Figure 2 shows a link in hoist/elevator ropes;
Figure 3 shows the electrical system for the invention;
Figure 4 which is disposed on the same sheet of formal drawings as Figures 1 and 2, is an example of the application of a load or tensile force measuring means; and Figure 5 is an alternative mine hoist.
Figure l shows a mine hoist, comprising a drum or driving pulley 4, over which one or several ropes run.
Figure l is a friction hoist and the intention is also to measure the condition of the friction slots which are to be found around the periphery of the pulley 4. The hoist also comprises a hoist cage/skip 5 and a counterbalance 6 as well as ropes 7, 8. Alternatively, the counterbalance 6 can be replaced by a second hoist cage or a second skip It is of great interest to monitor the condition of the ropes 7, 8 and, in case of a friction hoist, also the condition of the friction slots around the periphery of the driving pulley.
A system consisting of rope force measuring devices l, 2 is located between the ropes and the hoist cage 5 and between the ropes and the counterbalance 6, respectively, and the output signals from these devices l, 2 are processed and transmitted to a control equipment 3, which can be employed for a plurality of purposes according to the US invention.
I.
2~84 The rope force measuring device may, for example, consist of a strain gauge mounted in a device according to Figure (see below?, or of a transducer of magneto-strictive type, semiconductor detectors, or the like.
The link between the force measuring devices and the hoist cage/the skip and the counterbalance, respective-lye can be arranged according to Figure 2. Figure 2 shows the connection to the hoist cage and to the counterbalance, respectively, at the arrow F, and the hoist cage and the counterbalance, respectively, are supported by four / -- pa -ropes in the shown case which are influenced by the tensile forces Fly F2, F3 and F4. Between the ropes 9 and the compensating links 2Q and 21, respectively, there are arranged links 22, the construction of which is clear From Figure 4. The linkage arrange-ennui is constructed so as to minimize the effect of uneven load.
figure shows a cast or forged link 22 provided with a window or recess 23 with a central web or member 24. A number of strain gouges 25 are arranged in the window adjacent the central web, said strain gauges being arranged in pairs and being two, four, six, eight, etc., in number. As mentioned above, it is of course possible to use other types of transducers as well, and the output signals from the strain gauges 25 are put together so that a measure of the respective load or tensile force in the rope (Fluff) is indicated. The web 24 may be made thicker at the end portions, whereby the strain will be concentrated at the center of the web.
A rupture on the central web 24 does not involve any safety risk as far as the winder or hoist is concerned, since, of course, the rest of the linkage entirely carries the hoist cage or the counterbalance.
Figure 3 shows the control equipment 3 in the form of a block diagram, and it comprises a stationary unit I and a movable unit 27, which accompanies the skip/hoist cage, between which units there are radio communication ultrasonic communication, optical communication and/or induction transmission that is, wireless communication. To save energy normally only the receiver aye in the movable unit is constantly supplied with voltage whereas the transmitter unit lob of the control equipment (the movable unit) requests information via a control signal which also starts the transmitter lob (via a contact/switch 18~. To save further energy for example from the battery connected to the movable unit), the strain gauges 25 are designed with the greatest possible resistance values.
The hoist cage 5 (the skip) is suspended from a number of ropes I figure 3), and the load or tensile force in the ropes is measured according to the above (at 1, I The measuring signal is amplified at 13 and at 14 there is arranged a measurement ton--final.
:~2~8~
The output signals from thy measuring devices 1, 2, 25 are supplied to a calculating device or a processing unit 15, in which, for example, Fun Jan be computed, where Fun is the rope force -For no toe ape n- Also Flax Fin can be computed, i.e. the greatest d~ff~e~ee button two ropes. If a value of sun or Flax _ Fin is owned, which is greater or smaller than a predetermined vowel an emergency stop signal, for example, can be generated.
Dry inlays can ye obtained in the device 15) for example a signal or the distribution between the loads, maximum or mini-sum Dow etc.
ye ought signal from the device 15 is possibly supplied to a multiplex device 16 (switched in at 17) in order to deliver, in the proper sequence, different signals, representative of the rope condition, to the transmitter 19b which transmits signals in a wireless manner to the receiver 19c of the stationary unit, from where signals are transmitted via a channel selector 20 and a digital/analog convertor 21, and an output signal is obtained at 29.
The monitoring device can be completely or partially positioned on the hoist cage (5) and/or on the counterbalance (6) and/or can be located outside of these (in a control room or in the vicinity thereof).
The position of the hoist and the weight of the ropes are derived from the device 28, and during the calculation in 21 these values are taken into consideration From the stationary unit 26 signals can be transmitted to the ablaze unit 27 (transmitter 19d to receiver aye) in order to slot the desired signals in the movable unit, to switch in the receive I (via I and so on.
The hollowing use is of specific interest:
Determination of new load which is obtained from sun, and informal tin about the hoist depth (see at 28). Net load = Fun - empty hoist cage - part of lower rope. The information can be used as a measure of overload, empty discharge, etc.
I_ ~2~2~84 Exceeding the maximally permitted uneven load distribution between ropes This is derived from Flax _ Fin Max n This results it for example an emergency stop or information Jo the operating staff.
Load distribu~i~n, which is derived from Fun. This can be used us i~f~rma~ion about service activities.
Sue of the signals Fun can give dynamic information, for example byway oscillations in the system, which can be used for control purples.
If one of the signals on drops below a certain value, for example because of wedging of the skip, alarm is given.
If Fun from both hoist cages is indicated, this can be used for optimum start of the drive motor. A driving moment, corresponding to the torque distribution or the unbalance 9 is applied before the brakes on the driving pulley or the drum are lifted The foregoing description has shown two-way communication, whereby the transmitter on the hoist cage (the skip) can be made to start transmitting at the command of the control room. It is, however, possible to save the battery and simultaneously avoid two-way communication by utilizing the contact or limit switch of the hoist cage at the end positions of the skip door to generate making and breaking within a pertain selected time. Otherwise, the equipment positioned on the hoist cage/the skip is automatically shut off, and the battery is saved. Switch-on occurs when said switch is again operated, that is, when the hoist the skip it used gain.
In those cases where there is no passenger lift cage 7 the equipment con he activated by pressing the destination pushbutton.
TFanS~lSSiOn of information from the mine hoist 5 to the control room 3 con tare place by inductive transmission via the steel hoist rope or via air and radio waves. The damping in the shaft for radio waves in air is treat.
~2~2~34 To reduce the power consumption and increase the information content, a change can be made From an inductive system to radio transmission. To be able to cope with long -transmission distances, the rope 7 is utilized as a wave conductor (see Figure 5). A
radio ran sitter 30 on the hoist cage 5 transmits via a suitable aerial 31 to toe rope 7, and with another suitable aerial 32 radio waves are intercepted and detected in the receiver 3. The numeral I designates the rope drum, which disconnects radio waves gape-~itively to a greater or smaller extent and is able to generate extinction signals and thereby fade-out. This can be eliminated, for example by transmitting on two or more wavelengths or by sweeping the frequency of the transmitter and by broadband detecting in the receiver 3, or by means of two or more aerials (32, 34) post-toned along the rope. A suitable frequency is 10_60 MHz.
The invention according to the above can be varied in a number of ways within the scope of the following claims.
The link between the force measuring devices and the hoist cage/the skip and the counterbalance, respective-lye can be arranged according to Figure 2. Figure 2 shows the connection to the hoist cage and to the counterbalance, respectively, at the arrow F, and the hoist cage and the counterbalance, respectively, are supported by four / -- pa -ropes in the shown case which are influenced by the tensile forces Fly F2, F3 and F4. Between the ropes 9 and the compensating links 2Q and 21, respectively, there are arranged links 22, the construction of which is clear From Figure 4. The linkage arrange-ennui is constructed so as to minimize the effect of uneven load.
figure shows a cast or forged link 22 provided with a window or recess 23 with a central web or member 24. A number of strain gouges 25 are arranged in the window adjacent the central web, said strain gauges being arranged in pairs and being two, four, six, eight, etc., in number. As mentioned above, it is of course possible to use other types of transducers as well, and the output signals from the strain gauges 25 are put together so that a measure of the respective load or tensile force in the rope (Fluff) is indicated. The web 24 may be made thicker at the end portions, whereby the strain will be concentrated at the center of the web.
A rupture on the central web 24 does not involve any safety risk as far as the winder or hoist is concerned, since, of course, the rest of the linkage entirely carries the hoist cage or the counterbalance.
Figure 3 shows the control equipment 3 in the form of a block diagram, and it comprises a stationary unit I and a movable unit 27, which accompanies the skip/hoist cage, between which units there are radio communication ultrasonic communication, optical communication and/or induction transmission that is, wireless communication. To save energy normally only the receiver aye in the movable unit is constantly supplied with voltage whereas the transmitter unit lob of the control equipment (the movable unit) requests information via a control signal which also starts the transmitter lob (via a contact/switch 18~. To save further energy for example from the battery connected to the movable unit), the strain gauges 25 are designed with the greatest possible resistance values.
The hoist cage 5 (the skip) is suspended from a number of ropes I figure 3), and the load or tensile force in the ropes is measured according to the above (at 1, I The measuring signal is amplified at 13 and at 14 there is arranged a measurement ton--final.
:~2~8~
The output signals from thy measuring devices 1, 2, 25 are supplied to a calculating device or a processing unit 15, in which, for example, Fun Jan be computed, where Fun is the rope force -For no toe ape n- Also Flax Fin can be computed, i.e. the greatest d~ff~e~ee button two ropes. If a value of sun or Flax _ Fin is owned, which is greater or smaller than a predetermined vowel an emergency stop signal, for example, can be generated.
Dry inlays can ye obtained in the device 15) for example a signal or the distribution between the loads, maximum or mini-sum Dow etc.
ye ought signal from the device 15 is possibly supplied to a multiplex device 16 (switched in at 17) in order to deliver, in the proper sequence, different signals, representative of the rope condition, to the transmitter 19b which transmits signals in a wireless manner to the receiver 19c of the stationary unit, from where signals are transmitted via a channel selector 20 and a digital/analog convertor 21, and an output signal is obtained at 29.
The monitoring device can be completely or partially positioned on the hoist cage (5) and/or on the counterbalance (6) and/or can be located outside of these (in a control room or in the vicinity thereof).
The position of the hoist and the weight of the ropes are derived from the device 28, and during the calculation in 21 these values are taken into consideration From the stationary unit 26 signals can be transmitted to the ablaze unit 27 (transmitter 19d to receiver aye) in order to slot the desired signals in the movable unit, to switch in the receive I (via I and so on.
The hollowing use is of specific interest:
Determination of new load which is obtained from sun, and informal tin about the hoist depth (see at 28). Net load = Fun - empty hoist cage - part of lower rope. The information can be used as a measure of overload, empty discharge, etc.
I_ ~2~2~84 Exceeding the maximally permitted uneven load distribution between ropes This is derived from Flax _ Fin Max n This results it for example an emergency stop or information Jo the operating staff.
Load distribu~i~n, which is derived from Fun. This can be used us i~f~rma~ion about service activities.
Sue of the signals Fun can give dynamic information, for example byway oscillations in the system, which can be used for control purples.
If one of the signals on drops below a certain value, for example because of wedging of the skip, alarm is given.
If Fun from both hoist cages is indicated, this can be used for optimum start of the drive motor. A driving moment, corresponding to the torque distribution or the unbalance 9 is applied before the brakes on the driving pulley or the drum are lifted The foregoing description has shown two-way communication, whereby the transmitter on the hoist cage (the skip) can be made to start transmitting at the command of the control room. It is, however, possible to save the battery and simultaneously avoid two-way communication by utilizing the contact or limit switch of the hoist cage at the end positions of the skip door to generate making and breaking within a pertain selected time. Otherwise, the equipment positioned on the hoist cage/the skip is automatically shut off, and the battery is saved. Switch-on occurs when said switch is again operated, that is, when the hoist the skip it used gain.
In those cases where there is no passenger lift cage 7 the equipment con he activated by pressing the destination pushbutton.
TFanS~lSSiOn of information from the mine hoist 5 to the control room 3 con tare place by inductive transmission via the steel hoist rope or via air and radio waves. The damping in the shaft for radio waves in air is treat.
~2~2~34 To reduce the power consumption and increase the information content, a change can be made From an inductive system to radio transmission. To be able to cope with long -transmission distances, the rope 7 is utilized as a wave conductor (see Figure 5). A
radio ran sitter 30 on the hoist cage 5 transmits via a suitable aerial 31 to toe rope 7, and with another suitable aerial 32 radio waves are intercepted and detected in the receiver 3. The numeral I designates the rope drum, which disconnects radio waves gape-~itively to a greater or smaller extent and is able to generate extinction signals and thereby fade-out. This can be eliminated, for example by transmitting on two or more wavelengths or by sweeping the frequency of the transmitter and by broadband detecting in the receiver 3, or by means of two or more aerials (32, 34) post-toned along the rope. A suitable frequency is 10_60 MHz.
The invention according to the above can be varied in a number of ways within the scope of the following claims.
Claims (11)
1. A device for measurement and signal transmission in a hoist or elevator including a skip/hoist cage, character-ized in that between a rope or ropes of the hoist or elevator and the skip/hoist cage (5) and/or a counterbalance (6) there are arranged force measuring means (1,2) delivering output signals which are adapted to be supplied to a signal processing device (3) for obtaining different signals for monitoring a load in the rope or in the different ropes, also in the case of a hoist or elevator in motion, which signals are adapted to be transmitted to a monitoring device (26) which is sta-tionarily mounted in relation to the skip/hoist cage.
2. Device for measurement and signal transmission according to claim 1, characterized in that the measuring means (25) are placed in links (22) between a rope of the hoist or elevator and the skip/hoist cage (5) and between this rope and the counterbalance (6), respectively, and arranged at windows or recesses (23) in links around a central web (24), suitably in pair number and being arranged pairwise on either side of the web.
3. Device for measurement and signal transmission according to claim 2, characterized in that the measuring means (25) consist of strain gauges, of magnetoelastic trans-ducers, of semiconductor transducers, or of other types of force transducers.
4. Device for measurement and signal transmission according to claim 2, characterized in that the central web (24) comprises end portions and a centre, and is thicker at the end portions than at the centre, whereby the strain is concentrated at the centre of the web.
5. Device for measurement and signal transmission according to claim 1, characterized in that the output signals from said measuring means which correspond to rope forces are adapted to be summed up in the signal processing device (15), or that the greatest difference in output signal for two ropes or the maximum or minimum load in the ropes or the distribution between the loads in the ropes is adapted to be computed in the signal processing device, whereby when exceeding a certain value, an emergency stop signal is arranged to be generated.
6. Device for measurement and signal transmission according to claim 1 or 5, characterized in that it comprises a movable device, andin that signals are adapted to be trans-mitted from the stationary monitoring device (26) to the movable device (27) for selecting a certain desired information.
7. Device for measurement and signal transmission according to claim 1, characterized in that it comprises a movable monitoring device including a transmitter means (19b) arranged to be switched to an energy source (18), upon a switching-in signal, whereas a receiver means (19a) in the same device is permanently connected to the energy source.
8. Device for measurement and signal transmission according to claim 7, wherein said energy source is a battery.
9. Device for measurement and signal transmission according to claim 1, characterized in that the signal trans-mission is arranged to be switched in via a contact or limit switch of a hoist gate.
10. Device for measurement and signal transmission according to claim 1, characterized in that the signal trans-mission is arranged to take place by means of radio transmission within the frequency range 10-60 MHz, a rope of said hoist or elevator being used as a wave conductor.
11. Device for measurement and signal transmission according to claim 10, characterized in that the radio trans-mission is arranged to take place on two or more wavelengths, or by sweeping the frequency of a transmitter and broadband detection.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000423003A CA1212184A (en) | 1983-03-07 | 1983-03-07 | Rope force measuring means |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000423003A CA1212184A (en) | 1983-03-07 | 1983-03-07 | Rope force measuring means |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1212184A true CA1212184A (en) | 1986-09-30 |
Family
ID=4124727
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000423003A Expired CA1212184A (en) | 1983-03-07 | 1983-03-07 | Rope force measuring means |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1212184A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103502132A (en) * | 2011-02-22 | 2014-01-08 | 西马格特宝有限公司 | Cable load measuring element with radio transmission of measured values |
-
1983
- 1983-03-07 CA CA000423003A patent/CA1212184A/en not_active Expired
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103502132A (en) * | 2011-02-22 | 2014-01-08 | 西马格特宝有限公司 | Cable load measuring element with radio transmission of measured values |
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