DE1055832B - Method and device for indirect measurement of the drive torque of flow converters - Google Patents

Description

Method and device for indirect measurement of the drive torque of flow converters The invention relates to a method and a method therefor Suitable device for indirect measurement of the flow rate from a flow converter (Pöttinger converter) torque output with blade adjustment.

Flow converters are due to their ability to convert momentum into able to generate a strongly changing drive torque that occurs when starting and reached a particularly high peak value with full bucket opening and depending on Converter design can be a multiple of the drive torque. Hence is straight In the case of such power transmissions, there is often an ongoing torque measurement and monitoring desirable to provide an indication of the stress on the transmission medium or the to maintain driven tools and to prevent overloading of these parts. This is of increased importance when driving machines that are not visible or tools that are difficult to access and difficult to remove, such as B. on deep drilling rigs.

For flow converters with constant drive speed and unchangeable Power consumption, a torque measurement is possible in such a way that the reaction torque exerted on the stationary guide vanes and thus on the converter housing is determined; this results together with the constant converter drive torque the size of the respective output torque. However, such a type of measurement can be omitted structural reasons often apply only with difficulty, moreover it is only for the narrow area of converters with constant drive speed and unchangeable Blade position useful. In another, common for drives of any type Torque measurement is a so-called dynamometer between the power transmission elements switched. However, a dynamometer must transmit the full torque and accordingly be strong and large in size. Apart from the considerable construction costs In addition, in many cases it is difficult or impossible to accommodate due to lack of space.

The invention now proposes for power transmissions with a flow converter with blade adjustment a new type of measuring method and an associated device for indirect measurement of the output torque, which has the aforementioned disadvantages avoid. The measuring method according to the invention consists in that the respective values the blade opening s, the output speed n2 and - if variable - also the drive speed n1 of the converter can be measured individually and that these individual measured values thus influenced by correction devices and in a suitable display device be brought to interact in such a way that their moment display at least in Main measuring range when enlarging the blade opening, when increasing the drive speed and when the output speed drops to about the same extent as this actually does achieved converter output torque increases, and vice versa.

The measuring device used to carry out this method comprises accordingly one measuring element each for measuring the respective values of the blade opening, the output speed and - if variable - also the drive speed, furthermore a display device influenced by these individual measured values, as well as correction devices for one or more individual measured values, so that the moment display is at least in Main measuring range depending on the blade opening s, the drive speed n1 and the output speed n2 changes in the same way as above for the Procedure specified. It is advisable to use the basic operating values for the individual measurements (s, n1, n2) easily transferable and in particular similar state variables such as such as mechanical adjustment variables or forces, preferably electrical, hydraulic or pneumatic measured values. The converter speeds can be measured in easily done by small measuring pumps or measuring generators.

The blade openings s, the output speed zag and - as far as variable - the drive speed n1 of the converter always clearly determines that of the converter output torque 1V12, d. H. this is a function of the first Company sizes: M2 = f (s, n1, n2). These relationships can easily be used for every type of converter empirically determined on the test bench and shown in the form of graphs will. Such a converter diagram is shown in FIG. 1, assuming a constant input speed n1, above the output speed n2 as the abscissa the output motors M2 have been plotted as ordinates. Those with 100 ° / o, 750 / o The curves marked etc. correspond to the output torque M2 in the case of a guide vane opening from 100% (full opening) or at 75% etc. As can be seen, M2 falls with increasing Output speed n2 from approximately linear. From the different altitudes of the Family of curves for s = 1000 / o, 75 ° / o etc. can also be seen that M2 increases with increasing Blade opening also increases, but not quite in a linear relationship For s. If the input speed n1 is also variable, the output torque increases depending on n1 parabolically an according to the formula M2 = k - n where k means a constant value for each converter.

On the basis of these known for each transducer or ascertainable by experiment It is possible for the instrument maker to use the individual measuring elements for the basic operating values of s, n1 and n2, the display device and the correction devices to be trained in this way - for example using springs with the corresponding characteristics, Cam disks, suitable lever ratios or the like - that at least in the main measuring range each of the basic operating values s, z1, n2 have an approximately equal influence on the momentary display the measuring device acts as on the actual converter output torque. So can for example the measuring element for n2 and the associated correction device in Connection with the display device be designed so that with increasing output speed n2 the moment display decreases approximately linearly according to the curves in FIG. 1. The same applies analogously to the design of the measuring elements and the correction devices etc., which are assigned to the adjustable blades and the drive speed n1.

The advantages of the measuring device according to the invention consist essentially in that this is to be measured without regard to the absolute value of the greatest Torque built relatively small and even with limited space can be easily accommodated. Such a measuring device can even on already existing systems afterwards without any particular difficulties attach. When using easily transferable measured values - for example with electrical ones or pneumatic measured values - you also have the greatest freedom of movement in terms of space Arrangement of the correction devices and the display device, so that these only in consideration of space and visibility at distant from the power transmission Places can be provided. For the measurement of the basic operating parameters, sometimes use commercially available measuring elements such as measuring pumps or measuring generators.

Devices have already been proposed which are dependent on on the output speed n2 or on the ratio of the output to the drive speed n2 / n1 of a flow circuit control any switching processes. Here is however, the influence of variable blade openings has not been taken into account, and also leaves the speed ratio n2 / n1 - even with unchangeable blade openings - no clear conclusion about the converter output torque.

Further details of the invention are based on a few exemplary embodiments explained in more detail in the drawings. Here, FIG. 1 shows what was already described at the beginning Diagram for the actual course of the converter output torque M2 as a function of the converter output speed and the percentage blade opening, FIG. 2 a schematic representation of a measuring device according to the invention for a transducer with variable output speed, variable blade opening and constant Drive speed, Fig. 3 is the diagram of a measuring device for a converter, whose all basic operating variables (s, n1, n2) are variable, FIG. 4 a hydraulic one Blade adjustment device with a correction cam, FIG. 5 a hydraulic one Blade adjustment device with rotatable depending on a converter speed Curve thumb as a correction device, FIG. 6 shows a section through a correction pressure relief valve and FIG. 7 is a schematic representation of a hydraulic or pneumatic one Remote transmission of the torque display to two display devices.

The torque measuring device shown schematically in FIG. 2 is intended for a flow converter with constant drive speed; the drive motor 1 is a diesel engine with a constant speed, but it could also be a squirrel cage motor. It drives the impeller 2 of the converter. The turbine wheel 3 is above the shaft 4 with the driven machine, not shown here in connection. In addition to the stationary guide vanes 5, the converter also has adjustable ones Guide vanes 6, which by turning the handwheel 7 on the threaded spindle 8, rack 9, pinion 10, central wheel 11 and gears or gear segments 12 are operable.

As a result of the constant converter drive speed n1, the output torque solely from the variable sizes of the blade opening s and the output speed determine n2. For this purpose, the rack 9 is with an extension the sliding faceplate of a liquid or gas-filled diaphragm bellows 13 in connection. When the guide vanes 6 are closed, the diaphragm bellows is the least compressed, at 1000 / o blade opening on the other hand most, so that the at Compression of the bellows 13 here increasing pressure a measure of the respective Blade position is. This pressure is via the line 14 in the space 15 a Diaphragm pressure cell 16 with membrane 17 and exerts on this depending on the blade position a correspondingly large adjustment force.

To measure the secondary speed tt2, which is also variable, a measuring pump 18 is provided which is driven via an intermediate gear 19 at a speed proportional to n2. The measuring pump sucks in liquid from a collecting container and conveys it back into the collecting container via the pressure relief valve 20. The pressure in the pump pressure line, which also rises with increasing pump speed, is a measure of n2 and is passed via line 21 into a second pressure chamber 22 of the aforementioned diaphragm pressure cell 16. The measuring pump pressure loads the membrane 17 in the opposite direction as the measuring pressure generated by the blade openings. The movements of the membrane are transmitted from the rod 23 to the pointer of a display device 24.

As can be seen, when the blade opening is enlarged, the increased Measuring pressure in the room 15 the moment display also increased, what with the increase of the actual converter output torque with increasing blade openings in agreement stands (see diagram according to FIG. 1). As the output speed n2 increases, the increasing measuring pump pressure in space 22 reduces the moment display, which also corresponds to the real conditions. So that the influence of the measuring pressure of the Blade openings on the one hand and the measuring pump pressure on the other hand in the correct Relation to each other, the pressure relief valve 20 is designed as a correction valve. Fig. 6 shows a similar valve on an enlarged scale in section. Because of the appropriately selected valve design grow with increasing valve lift the free valve passage cross-section and the force of the valve spring so on and result a measuring pump pressure which increases with increasing n2 in such a way that this increases upon interaction with the measuring pressure of the blade openings, at least in the main measuring range, one actually does achieved converter output torque results in approximately the same torque display. In this way a sufficient display accuracy can be achieved for most needs.

Fig. 3 shows the scheme of a measuring device for a flow converter, in which all three basic operating variables s, n1 and n2 are variable. The converter output shaft 26 drives a secondary measuring pump 27, which in connection with the correction valve 28, in the same way as in FIG. 2, a measuring pressure in the pressure line that increases with n2 29 generated. The converter guide vanes 30 are adjusted pneumatically Paths, whereby an air pressure originating from a pressure source in the line 31 through a reducing valve 32 is reduced to a selectable lower pressure in line 33 will. This then acts on the spring-loaded piston 34, which in the usual way Via a rack 50 and gears with the adjustable converter blades 30 communicates. A high air pressure in the line 33 results in large blade openings and vice versa, so that this pressure can easily be used as a measuring pressure. This Measuring pressure and the aforementioned secondary measuring pump pressure in turn act on different ones Sides of a membrane of a pressure cell 35.

The converter input shaft 36 drives a primary metering pump 37, which in connection with the correction valve 38, a primary measuring pump pressure which increases with n1 generated in line 39. This acts on the membrane of a second load cell 40. The membranes of the two load cells 35 and 40 are connected to one another by means of a rod 41 and connected to the pointer 42 of the display device. The arrangement is there taken so that when the blade opening is enlarged, s when increasing the drive speed n1 and as the output speed n2 decreases, the moment indicator of the pointer 42 increases, and vice versa. The correction valves 28 and 38 are again designed similar to FIG. 6, in such a way that at least in the main measuring range the measuring pump pressures for n1 and n2 such an influence when interacting with the measuring pressure of the blade opening exercise on the moment display, the approximately the actual influence of n1, n2 and s corresponds to the output torque.

There is also a pressure gauge 43 on each measuring pressure line, 44 and 45 are provided, on which the respective values of s, n1 and n2 can be read.

The measuring device according to FIG. 3 can also be modified to the effect that that instead of the correction devices 28 and 38 for n2 and n1 each have a correction device provided for n2 and s or n1 and s. The flow rate of the measuring pump without a correction device can then flow out through a simple throttle opening. The correction device for the measured values of the blade opening there is - as shown in Fig. 4 - expediently from a cam 47, which between the transmission means between the adjusting blades 30 of the converter and the adjusting piston 34 according to FIG. 3 (or is also connected to the diaphragm bellows 13 according to FIG. 2). When moving the adjusting piston 34 then, according to the shape of the cam, the roller 48, connecting rod 49 and rack 50 shifted in the desired dependence on the piston travel and accordingly adjusted the converter blades. The desired correction can be but also achieve that the spring 51 on the adjusting piston 34 according to FIG. 3 or of the diaphragm bellows 13 according to FIG. 2 designed for a corresponding progressive spring force will.

Instead of a correction cam, according to FIG. 5, a corresponding shaped curve thumb 51 be provided, which by means of the back gear 52 under the Influence of n1 or n2 is rotated and the different at different speeds Brings meridian curves to effect. With such a device can be only two variable basic operating parameters (e.g. s and n2) theoretically even im achieve an exact moment display over the entire working range of the converter. With analogous The use of two such curve thumbs is also available for converters with three variable basic operating variables s, n1 and n2 ensure an accurate torque measurement throughout Workspace. The arrangement is to be made in such a way that two of the individual measured variables (about those of s and n2) act as shown in FIG. 5 on one thumb and that the resulting measured variable obtained in the form of the displacement of the rod 49 and the third individual measured variable (n1 for the selected example) the second Move or twist curve thumb. The resulting measured variable then gives immediately the final moment display.

Furthermore, an embodiment of the measuring device is possible in which a separate correction device is provided for each individual measured value. The correction devices are advantageously designed in such a way that when increasing or decreasing the basic operating values s and n1, the associated Measured values at least in the main measuring range in the same ratio as this actually change the output torque achieved by the converter; d. H. so that for example at with increasing n1 the associated measured value (measuring pressure or the like) in the same ratio increases like the converter output torque, i.e. approximately quadratic dependence from n1. If a measuring pump is used for n1, it is sufficient as a correction device a simple throttle opening on the pump pressure line, because then the pump is already generates a pressure that increases parabolically with n1. The associated Correction device for the n2 measured value is expediently designed so that this with increasing n2 it also grows, in the opposite proportion to this actually achieved, decreasing converter output torque. The n2 measured value is thereby grow approximately linearly, since the output torque n2 - as from the curves in FIG. 1 can be seen - decreases approximately linearly with increasing n2. When using a measuring pump A correction valve according to FIG. 6 can then be used for the n2 measurement. Here flows the pressure medium coming from the secondary measuring pump through line 29 (see Fig. 3) the valve and moves the valve piston 53 against the force of the Spring 54 to the right, with the piston having a specially designed outlet opening 55 releases. In the present case, the opening has a triangular shape, so that the free The passage cross-section grows with the square of the piston stroke and therefore - a linear one Spring characteristics assumed - the measuring pump pressure as a function of n2 despite quadratically increasing pump delivery rate only increases approximately linearly as desired. A suitable other shape of the valve opening 55 can - possibly still in Connection with a valve spring with special characteristics - also any other type of correction of the metering pump pressure can be achieved.

In addition, it should be noted at this point that the inventive Measuring device, of course, also on flow converters with adjustable pump or turbine blades, yes in principle even on converters with arbitrarily designed Organs for power regulation, for example with blade rings that can be engaged and disengaged or Ring slide, can be used. Furthermore, the measuring device can also measure negative output torques (measuring range B according to FIG. 1, converter braking) or for Measurement of the output torques at a negative output speed (measuring range C according to Fig. 1, output shaft rotates backwards).

In many cases, a torque display is on remote from the converter or on several display devices. One in FIG. 7 is recommended here illustrated hydraulic or pneumatic transmission of the torque measurement result on the display device or devices. The load cell 16 corresponds to the number with the same number Can of the measuring device according to Fig.? and is also on line 21 with the Secondary measuring pump pressure and via line 14 with the blade opening measuring pressure applied. The rod 23 attached to the membrane 17 is different from FIG 2 is connected to a piston 56 of a cylinder 57. Depending on the rash the membrane 17 is displaced in the cylinder 57, a corresponding amount of liquid or a corresponding pneumatic pressure is generated; this state variable can then by means of simple pipelines - i.e. with little construction effort - to the than Manometer trained, correspondingly calibrated display devices 58, 59 forward.

The proposed measuring device can also advantageously serve to limit the torque transmitted by the flow converter, preferably as overload protection for the drilling tools on deep drilling rigs. To this end are the elements that display or transmit the final torque result the measuring device, for example the rod 23 or 41 according to FIG. 2 or 3 or a connecting line of the cylinder 57 according to FIG. 7, with the adjusting device for the converter blades or with the power control element of the drive motor in such a way in operative connection that the maximum permissible converter output torque is exceeded by reducing the converter blade opening or by throttling the engine output is prevented. In the embodiment of FIG. 3, for example, the rod 41 when the maximum permissible converter output torque is exceeded in this way to the Reduction valve 32 act that the openings of the converter vanes 30 by one corresponding amount can be reduced.

The device explained above can also be modified in this regard be that the measuring result transmitting or displaying elements of the measuring device with the blade adjustment device of the converter or with the power control element of the engine are connected in such a way that the converter output torque on a is kept constant.

Claims (20)

PATENT CLAIMS: 1. Method for indirect measurement of the output side Torque of flow converters with blade adjustment, characterized in that that the respective values of the blade opening (s), the output speed (n2) and - insofar as variable - the drive speed (n1) of the converter also measured individually and that these individual measured values are also influenced by correction devices and are brought together in a display device so that their Momentary display at least in the main measuring range when enlarging the shovel opening (s), when increasing the input speed (n1) and when decreasing the output speed (1t2) approximately to the same extent as the converter output torque actually achieved here (M2) increases and vice versa. 2. The method according to claim 1, characterized in that that with the individual measurements of the basic operating values (s, n1, n2) easily transferable and in particular similar state variables are generated as measured values. 3. Procedure according to claim 2, characterized in that in the case of the individual measurements the basic operating values (s, n1, n2) electrical measured values are generated. 4, method according to claim 2, characterized indicated that for the individual measurements of the basic operating values (s, n1, 11.2) hydraulic or pneumatic pressure values can be generated. 5. Measuring device for Implementation of the method according to one of Claims 1 to 4, characterized by one measuring element each (13, 18; 34 and 51, 27, 37) for measuring the respective values of the Blade opening (s), the output speed (n2) and - if variable - also the drive speed (n1) as well as influenced by one of these individual measured values Display device (16, 24; 35, 40 to 42) and correction devices (20; 28, 38) for one or more individual measured values. 6. Measuring device according to claim 5, characterized in that the measuring element for the output speed (n2) or a associated correction device is designed such that the associated measured value also increases at least in the main measuring range with increasing n2, and in inverse proportion to the actually achieved decrease Output torque (M2). 7. Measuring device according to claim 6, characterized in that that the measuring element for the drive speed (n1) or an associated correction device is designed in such a way that the associated measured value is at least in the main measuring range increases approximately quadratically with increasing n1. B. Measuring device according to claim 6 or 7, characterized in that the measuring element for the blade opening (s) or an associated correction device is designed such that the associated Measured value at least in the main measuring range as a function of the blade opening values (s) changed in the same ratio as the output torque actually achieved (M2) - 9. Measuring device according to claim 5, characterized in that with two or with three measuring elements for the variable basic operating parameters (s, n1, n2) or two measuring element (s) are provided with a correction device (20 or 28, 38) are. 10. Measuring device according to one of claims 5 to 9, characterized in that that for measuring the output speed (n2) and - if variable - also the drive speed (n1) a measuring pump (18; 27, 37) is provided in a manner known per se. 11. Measuring device according to claim 10, characterized in that on the pressure line the measuring pump (s) each have an overpressure valve (20; 28, 38; 53 to 55) with an increasing free passage cross-section with increasing valve lift (55) and increasing valve spring force (54) is arranged. 12. Measuring device according to one of claims 5 to 11, characterized in that for measuring, the variable Blade opening value (s) a diaphragm bellows (13) or a diaphragm pressure cell is provided is whose moving part with the adjustable blades or the blade adjustment devices (9) is in communication such that the hydraulic or pneumatic pressure in the diaphragm bellows or the like also grows with increasing blade opening, and that the display device (16, 24) is subjected to this pressure. 13. Measuring device according to one of claims 5 to 11, for a flow converter with hydraulic or pneumatic blade adjustment, this with increasing adjustment pressure - which is controlled by a valve and on a spring-loaded adjusting piston acts - also causes the blade opening to increase, characterized in that that the adjustment pressure at the same time as a measuring pressure and to act on the display device (35, 41, 42) is used. 14. Measuring device according to claim 12 or 13, characterized in that that the measured values for the vane opening are corrected by means of a cam disk (47), between the transmission means (34, 49, 50) between the adjustable blades the converter and the diaphragm pressure cell or the diaphragm bellows (13) or the adjusting cylinder is switched. 15. Measuring device according to one of claims 5 to 14, with conversion the variable basic operating values (s, n1, n2) in hydraulic or pneumatic Pressure values, characterized by membrane pressure cells to which one of these pressure values is applied, their moving parts (membranes) via appropriate transmission means (rods, Lever) act together on the display element. 16. Measuring device according to claim 14, characterized in that instead of the cam a correspondingly shaped Curve thumb (51) is arranged under the influence of the variable output speed (n2) or drive speed (n1) is rotatable. 17. Measuring device according to claim 16, for flow converters with variable input and output speed as well as adjustable Shovel opening, characterized in that two cam thumbs are provided and that the first thumb of the curve can be moved under the influence of two individual measured variables or is rotatable and the second curve thumb under the influence of the resulting Measured variable of the first curve thumb and the third individual measured variable can be shifted or is rotatable and that also the torque display element as a function of the resulting measured variable of the second curve thumb is adjusted. 18. Measuring device according to one of claims 5 to 17, in particular for remote display or display several display devices, characterized by hydraulic or pneumatic transmission (56, 57) of the torque measurement result on the display device (s) (58, 59). 19th Device for torque limitation for drive with flow converter with blade adjustment, preferably marked as overload protection for the drilling tool on deep drilling rigs by using a method or a measuring device according to one of the claims 1 to 18, the elements indicating or transmitting the torque measurement result the measuring device with the adjusting device for the converter blades or with the power control element of the drive motor are in operative connection in such a way that exceeding a maximum permissible converter output torque by reducing it the converter blade opening or by throttling the engine power is prevented. 20. Device for torque control for drive with flow converter with blade adjustment, characterized by using a method or a measuring device according to a of claims 1 to 18, wherein the torque result displaying or transmitting Elements of the measuring device with the adjusting device for the converter blades or are in operative connection with the power control element of the drive motor, that the converter output torque is kept approximately constant.