WO2014092523A1

WO2014092523A1 - Device for controlling the alignment of transmission shafts

Info

Publication number: WO2014092523A1
Application number: PCT/MA2013/000031
Authority: WO
Inventors: Abdennebi TALBI
Original assignee: Universite Sidi Mohamed Ben Abdellah
Priority date: 2012-11-23
Filing date: 2013-11-21
Publication date: 2014-06-19

Abstract

The present invention concerns an apparatus for controlling the alignment of rotating shafts and a calibration and control procedure. The aim of the apparatus is to identify the direction of defects, and to separately measure the amplitude of both radial defects and angular defects, since this makes it possible to test and validate a perfect alignment. It provides the possibility of displaying the indications of relative movements corresponding to each type of defect by using different control devices: spirit level, comparator, two pointer indicators and two plug ring gauges.

Description

DEVICE FOR MONITORING THE ALIGNMENT OF TREES OF

TRANSMISSION

DESCRIPTION:

1. Technical field to which the invention relates:

The present invention relates to a rotary shaft alignment control apparatus and a calibration and control procedure.

Indeed, most equipment or industrial installations, whatever their fields of use, are composed of a motor system (power generator) and a receiver system (power consumer). The engine and receiver systems are each provided with a shaft for transmitting power from the engine system to the receiver system. However, when installing the motor system and / or receiver, it will be necessary to proceed to their relative positioning to align along the same axis; the output shaft of the engine system and the input shaft of the receiver system. The power transmission between the two shafts is provided by couplings that can be rigid, elastic or articulated. The elastic couplings and essentially the rigid couplings require a perfect coaxiality of the two shafts and consequently the total elimination of the axial, radial and angular defects. Hence the use of shaft alignment testers to identify and eliminate positioning defects in the motor and / or receiver systems. Such a task is generally assigned to maintenance agents who oversee the maintenance and availability of equipment and industrial installations.

2. State of the prior art:

Alignment devices having been the subject of US Patents 3,664,029; 3,733,706; 3,711,955; 2,638,676; 2,636,274; 2,656,607; 2,726,058 and 3,525,158, are generally devices capable of detecting tree misalignment in only two directions. Those that can be used to control an axial and radial misalignment require a displacement of their alignment structure radially with respect to the shafts to be aligned, as they must have one of the shafts rotated relative to the stationary alignment device. . This procedure is not only a long and delicate operation, but it introduces errors due to the constant requirement of the displacement of either the alignment device itself or one of the trees to be aligned. Another problem, which is in many cases due mainly to the very limited space available to install the alignment device and the congestion of the installation, preventing the operator to correctly install the device and to take steps. precise measurements. In many cases, the shafts are connected to systems such as electric or thermal motors and heavy industrial installations that can not be rotated relative to the alignment device because of the large resistant torques.

Other static alignment devices have been described in U.S. Patent Nos. 4,155,925; 4,161,068; 3192131. Patent 4,115,925 permits three-dimensional detection of the alignment by the use of two universal joints incorporating appropriately mounted position sensors. The communicating joints through the use of a telescopic link mounted on the forks of each universal joint.

In addition, the universal joint forks, which convert the positions of the shafts into exploitable coordinate information, must have a minimum size to allow mounting of the position sensors. This condition imposes the existence of a minimum space for the assembly of the forks of the universal joints and thus of the trees sufficiently spaced from each other.

Patent No. 4,161,068 provides misalignment information by using mechanical target rods provided with micrometers, in connection with two cooperating network surfaces forming moire fringes for detecting angular misalignment. In addition, the moire fringe pattern produced is difficult to interpret when the amplitude and direction of the misalignment.

Patent No. 3,192,631 uses eyeglasses having reticles and screens forming target screens with reticles. These particular elements may provide an indication of the misalignment direction, but can not provide an indication of the magnitude of the misalignment, and the trees must be tuned by trial and error, until an observation through the glasses will indicate that the alignment conditions are met.

Other static alignment devices have been described in patents filed in France: No. 2,436,966 and No. 2,534,017.

Patent No. 2,436,966 is based on the use of two cardan joints which each deliver an electrical signal emitted by a potentiometer. This signal is representative of the angular orientation of a universal joint relative to the other. The device must be rotated (pivoted) around the shafts, it can only be mounted on relatively distant trees, which is rarely the case for industrial plants.

Patent No. 2,534,017 uses radiation detectors producing beams projecting on detection devices, these detectors are mounted on supports connected to the shafts which must be arranged remotely in order to allow their assembly and to increase the accuracy of detection. This condition is rarely offered by industrial plants whose trees are generally arranged very close together and rarely provide space for mounting these devices.

Finally, other non-rotational alignment or static alignment devices have been described in US Pat. Nos. 5,077,905; No. 5,222,306; No. 5,371,953; No. 5,715,609.

Patent No. 5,077,905 uses a method based on laser alignment, consisting of a device emitting laser beams and the other receiver: The receiving part is pivotally mounted on its support to adjust better to the face of the laser. laser ray. The unit is bulky and requires more space and can only be mounted on relatively distant (distant) trees.

Patent No. 5,222,306 discloses a control method based on the use of comparators mounted on one of the supports linked to one of the two shafts by a pivot connection. This support to which the 3 comparators are fixed pivots around the shaft, a comparator fixed perpendicularly to the trees directly takes the measurements on the second shaft. While the two other comparators fixed parallel to the trees allow to detect the flatness of the surface of a plateau fixed on the second shaft and arranged perpendicularly to this shaft. The major disadvantage of this method is that it requires the disassembly of one of the two systems to separate the shafts to insert or remove the two supports in the form of hubs in or / and shafts.

Patent No. 5,371,953 is based on a method using two comparators and two tubes arranged respectively radially and axially to the trees to be controlled. On each support is fixed a tube and a comparator. A finger sliding along each tube allows to feel directly on the comparator fixed on the other support. The information delivered by each comparator corresponds to the cumulative number of radial and angular defects. The device requires sufficient space and trees relatively distant from each other and can not provide, separately, on radial and angular defects.

Patent No. 5,715,609 relates to a device based on two laser beam transmit / receive plates mounted in opposing face-to-face, each on one and the other of the supports which are removable around the trees to be controlled. . This method requires a good circularity and good surface condition of the trees, it also requires sufficient space to receive the supports and allow the device to pivot around the trees.

3. Presentation of the invention, advantage over the previous state:

The general object of the present invention is the design of a static alignment apparatus for rotating shafts and the establishment of a calibration and control procedure. The static alignment control device for rotating shafts allows the direction and amplitude of radial and angular defects to be separately detected. It allows the display of indications of the relative displacements corresponding to each type of defect by using different control devices: by bubble level (31), by comparator (7), by two pointers with pins / needles (38a, 38b) and by two smooth buffer rings (39a, 39b).

It makes it possible to control the alignment of shafts of different diameters or shafts of identical diameters but varying in a wide range of diameters (from 10 mm up to 150 mm) that are arranged very closely or remotely thanks to the pivot-sliding connection of the central rod (2) with respect to the hubs (1, 33) making the telescopic device thus allowing the two supports to be brought together or away from each other in order to adapt to the axial offset existing between the shafts to be controlled .

This device is characterized by its ability to carry out a set of controls and measurements without obligation to rotate the device around the axes of the trees, which will avoid associating the defects of circularity and roughness of the outside diameters of the trees with the defects of alignment and therefore not to distort the measurement. This is one of the major flaws of most of the previous inventions. Our invention has the merit of bearing on this defect by keeping the two supports constantly fixed and immobile with respect to the shafts during all phases of control, measurement and correction of the relative positions of the trees.

The device is also characterized by its robust, lightweight, adjustable, telescopic, flexible and self-supporting metal structure, its rigid components (parts), its precise connections, without internal games, without regular maintenance and without nuisance or risk for the environment. . 4. Detailed description of the embodiment of the invention:

The shaft aligning apparatus according to the invention (FIG. 3) consists of two telescopic supports (28 and 29), two hubs (1 and 31), a sliding and orientable carriage (41), a calibration device (17, 18 and 19) and two devices for indicating the angular orientation of the shafts (38a and 38b), a device for controlling radial and angular defects with the aid of comparator (1, 33, 41 and 7), two bubble level indicators (31) and a device for validating the perfect alignment with smooth buffer rings (39a / l and 39b / 33) . It is, therefore, versatile, flexible, autonomous and reliable.

The supports consist of two telescopic columns consisting of two hollow cylindrical tubes (28 and 29). The inner tube, integral with the "V" support (30) is adjusted and housed in the outer tube (28) which is connected to the hub by a ball joint (17 and 18). The two tubes slide relative to each other through the slide connection obtained by an oblong hole formed along the hollow outer tube (28). A screw-ecfou type fixing system (26 and 27) makes it possible to immobilize any relative movement of the two tubes and to adjust at the same height the axes of the two hubs. It also allows the direct attachment to bulky couplings and possibly, to take into account differences in the diameters of the trees to control. The "V" support (30) has stepped grooves disposed along its outer portion to adjust the useful length of the "V" support clamping cable to the shaft ends (Fig.2, Fig. 4). The "V" support uses a metal cable (49) having on one side an attachment ring to a clamping lever (45), (eccentric locking) to be positioned in the semicircular grooves of the carrier. "V" (Fig.6), on the other side, a nut (51) formed in a cylindrical section with two ends (52), having a hole for the passage of the cable and a cable clamping screw (50). The nipples exiting on each side of the nut (52) allow to adjust its positioning on one of the stepped grooves according to the diameters of the shafts (Fig.2, Fig.6).

Between each hub (1 and 33) and the moving part of the sliding support which is the hollow outer tube (28), a ball joint offers three degrees of freedom in rotation, it makes it possible to correct the manufacturing and assembly errors of the device during calibration. Thus, the dispersions of the production ribs will be corrected (eliminated) during the calibration by adjusting the orientation of the axis of each hub with that of the shaft on which it is mounted and to ensure that the coaxiality of the two axes of the hubs Calibration is necessary before the use of the device, it recommends the use of a standard cylindrical part (surface state and perfect geometry) on which will be fixed the two supports in " V "before calibration The solution presented allows to increase and improve the accuracy of the device, so that all direct control of the shafts can be done identically on the hubs. supports around the shafts, it will be limited to pivoting the sliding carriage and pivoting (41) about the axis of the central rod (2), (Fig.3).

The alignment of the shafts is controlled by transposition on the outer and inner surfaces of the hubs (1 and 33). Indeed, the defects (radial, angular) present on each tree reproduce identically on both hubs.

The two hubs are connected by a central cylindrical rod (2) forming a pivot-sliding connection with two balls (spherical balls) (4 and 36) which, in turn, are connected to the hubs by ball joints. These different connections allow the hubs to have the six degrees of freedom to position itself in a similar way to the trees to be controlled, thus integrating the misalignment existing on the trees. Thus, each hub takes the orientation and the position of the tree on which it is fixed. Indeed, the axis of the rod (2) connecting the two balls (4, 36) takes a particular orientation with respect to the axes of the hubs (1, 33) characterizing the coaxiality defects of the shafts. Thus, checking the alignment of the two shafts amounts to controlling the coaxiality of the axes of the two hubs (1 and 33) with that of the central rod (2). Indeed, the axis of the central rod is that of the carriage (41) sliding along the central rod (2) and serving as a support for the comparator (7). By simple translation of the sliding carriage (41), the comparator (7) allows to feel along two generatrices of the outer surface of each hub (1 and 33). These generators are inscribed, each in one and the other of the two perpendicular planes passing through the axis of the hubs and with respect to which they are considered to be perfectly parallel (Fig.3).

Before any check, it will be necessary to calibrate the device. This calibration consists in mounting the two supports on a standard cylinder, loosen the nut (19) and the screw (27), bring the two hubs together to fit (slide in) the smooth buffer rings. Then, to better adjust the coaxiality of the axes of the two hubs and their parallelism with that of the axis of the standard shaft. Then adjust, if necessary, the stacking of the thick calluses (59). Finally, tighten the nut (19) and the screw (27).

Controlling the angular defects of the shafts amounts to checking the parallelism of the two generators located in two orthogonal planes of the outer surfaces of the hubs (1 and 33) with the axis of the central rod (2).

The passage of the control from one generator to the other is obtained by the pivoting of the sliding carriage (41) at a 90 ° angle around the axis of the central rod (2) by acting on the wrist (8) . Maintaining and rectilinear guidance in each of the two stable rotational positions of the sliding carriage (41) are provided by a small ball (12) held engaged under the effect of the pressure of the spring (13), by tightening the screw in one or the other of the "V" grooves (R1 or R2) formed along the functional portion located on the central portion of the rod (2). Another circular groove in "V" (R3), located in the middle of the rod allows to position the slide carriage (41) in the middle of the two hubs (neutral point of the carriage) and possibly to switch to the control of parallelism along the second generator. Each generator must be located on one or other of the orthogonal planes passing through the hub axis.

Controlling the radial defects of the shafts is to identify the difference recorded by the comparator between the calibration step resulting in the perfect coaxality of the axes of each hub and the actual control step by probing along a circular path located on the outer surface of the hub.

With these two separate checks for radial and angular defects, the tree alignment tester identifies and measures both types of defects separately. Thus, the elimination of defects (repositioning) of the leading and driven trees will be fast, simple and accurate.

Depending on the case, one can control the alignment of the two trees by taking one or the other as reference; usually that of the receiving system imposing difficulties in its positioning. Thus, one proceeds to the probing of the hub-mounted generators on the shaft providing the most ease with its radial and angular positioning.

As we can act on the two trees to align them gradually with respect to one another. In this case, one must feel on the outer surfaces of the two hubs. It is desirable to start by aligning, in an approximate manner, the tree with the greatest difficulty before finalizing the alignment by acting on the second shaft, providing more ease and sensitivity to its positioning (orientation).

The adjustment of the alignment will be finalized by choosing the right stacking of the thickness shims to be inserted under one or the other of the four brackets of the engine or / and receiver systems or by acting on a positioning system screw / nut type. When the axes of the shafts are located at the same height, one carries out by planing (pivoting about a vertical axis) of the driving part and / or receiver.

Then we proceed to tightening the brackets.

The axes will be judged perfectly aligned as soon as the sliding carriage (41) could have reached the two extreme positions (end of stroke) on the right and left without any particular resistance which may be due possibly to a jamming of the smooth buffer rings (39a and 39b) in the bore of the hubs (1 and 33). These rings, designed just slippery in the bore of the hubs, serve as a control and validate the perfect alignment of the trees.

For the fixing of the supports to the shafts: the choice of the "V" shape of the lower part of the support makes it possible, on the one hand, to avoid the offset of the axes of the hubs with respect to the trees to be checked in particular during the control of the trees of different diameters, and on the other hand, to keep the support of the apparatus in a vertical position (stable equilibrium). In the end, this choice makes it possible to adapt to trees of varied diameters ranging from 10 mm up to 150 mm.

A wire rope (49) is used to bend the trees to be controlled with the supports. The choice of the effective length is ensured by the positioning of the nipple nut (51) with respect to the cable, then the pinching of the latter with the aid of the pressure screw (50).

Depending on the diameters of the shafts, the stepped grooves on either side of the upper faces of the "V" structure are used to hook the pin nut and to position the clamping lever (45). ) and thus guarantee total immobilization (complete connection) of the supports with respect to the trees to be controlled.

The tree alignment tester is equipped with two tree positioning indicators; one operates in absolute terms, it is two bubble levels (31), the other measures the offset angle of the two shafts using the needle pins (38a and 38b).

The spirit levels make it possible to ensure that the two shafts are in a perfectly horizontal, vertical position or at an identical inclination slope easily identifiable thanks to the adjustable spirit levels (31).

Thus, each hub is equipped with a spirit level to identify which tree will act to put it at the same level as the second tree.

The indicators of radial and angular defects of the trees to be controlled make it possible to better inform on the direction and the angle of inclination of the trees expressed in degrees. The two needle rods (38a and 38b), in complete connection with the central rod (2), each indicate the offset level of the shafts (shift of the central rod relative to the axes of the two hubs). The consultation of these two indicators is necessary at the beginning of each tree alignment check to better inform the meaning and the importance of the defects before finalizing the procedure of precise control of the defects by means of the comparator ( 7) and smooth buffer rings (39a and 39b).

5. Drawings (See Annex)

Figure 1 is a perspective of the shaft alignment apparatus comprising the different control devices mounted on the two hubs and positioned relative to the shafts with two supports.

Figure 2 shows the front view and the left view of the apparatus in mounted position and tightened on the shafts by means of a suitable clamping device.

Figure 3 shows the section (AA), taken from the left view of the device (Fig.2). It describes in detail all the technological solutions recommended and making it possible to achieve all the expected functions of the device.

Figure 4 shows, with the aid of the left view and the section (BB), the lower part of the support of the apparatus comprising a hollow tube and a "V" structure assembled by welding. The structure has two types of grooves arranged on either side of the upper part of the "V".

FIG. 5 shows, with the aid of the view from above and the section (DD), the nut with pins allowing, by its positioning with respect to the wire rope, the adjustment of the useful length of the cable and its attachment to using the nipples, in the stepped grooves of the "V" structure. Figure 6 shows the lever clamping / locking of the supports relative to the shafts. The section (CC) and the left view of the multiplication lever of the clamping force show the arrangement of the two positioning studs of the clamping / locking lever and the hooking axis of the wire rope.

Claims

Claims:

The static alignment device of the rotating shafts is characterized by: two hubs (1) and (33) connected by a solid cylindrical central rod (2) which tolerates any relative movement of the two hubs thanks to the choice of annular linear links between the rod (2) and the hubs (1) and (33) each equipped with a bubble level gauge (31), a telescopic support (28, 29) adjustable in height, a sliding carriage and swivel (41) equipped with a comparator (7) and two smooth buffer rings (39a, 39b), and a device for controlling the angular offset of the two shafts to be controlled by means of two stem indicators (38a ) and needle (38b). The connection between the two hubs, characterized by six degrees of freedom, allows the hubs (1) and (33) to have the same defects as those of the trees to be controlled. Thus, the control of the alignment of the shafts will be reported on the two hubs.

2- The device for controlling the static alignment of rotating shafts, according to claim 1, is characterized by the two parts of the support (28) and (29,30) which are intended, on one side, to support and each guide one of the two hubs (1) or (33) and on the other side, to be mounted on one or the other motor shaft or receiver. The support being telescopic, it allows a height adjustment of the two hubs through the connection slide, oblong hole, between the movable part of the support (28), integral with the hub and the fixed part (29), intended to be mounted on the trees.

3- The device for controlling the static alignment of rotating shafts, according to claim 2, is characterized by the fixed part of the support (29) completely bonded (welding) at its base to a hollow "V" structure (30). ) whose opening is characterized by an angle of 100 °, having a range on two generators modeled by 4 point links. This hollow structure allows, on the one hand the passage of a wire rope (49) in the middle of the contact points (shaft / structure in "V") and to adapt to the diameters of the shafts by means of stepped grooves arranged, on both sides, on the upper part of the "V" structure.

4- The device for controlling the static alignment of rotating shafts, according to claim 2, is characterized by the use of a metal cable as means for fixing the supports on the shafts (bending). The cable having an adjustable length that can be energized by means of locking levers (45) with eccentric axes (46, 48) having pins (47) for positioning at the end of the clamping stroke in a stable position guaranteeing a complete immobilization of the supports relative to the trees on which they are fixed.

5- The apparatus for controlling the static alignment of rotating shafts, according to claim 2, is characterized by a ball joint connecting each hollow outer tube (28) of the movable portion of the support of the two hubs (1) and (33). ). This ball joint makes it possible to correct and guarantee the parallelism between the axes of each hub and the standard cylinder on which the supports are fixed. Once the parallelism reached, the tightening of the nut (19) will condemn this link ball (removal of 3 degrees of freedom in rotation). The thick washers (59) make it possible to guarantee the positioning (adjustment) at the same level of the axles of the hubs (1) and (33) and consequently their coaxiality which must remain within an acceptable limit, for example <0.01mm.

The static alignment device of the rotating shafts, according to claim 1, is characterized by two hubs whose geometry of the surfaces of the outer diameter and the bore is precise (the tolerance limits of the cylindricity, circularity and straightness remain less than 0.01 mm), a good surface condition (roughness Ra <0.4 micrometer) and whose axes are perfectly coaxial (coaxial error <0.01mm) with the axis of each hub. These two hubs, on which reproduce the same misalignments as those existing at the level of the shafts on which they are mounted, are connected by a solid cylindrical central rod (2) providing a pivot-sliding connection with respect to two spherical balls. (4, 36), these same balls are linked to the hubs by ball joints without play due to the use of pressure springs (53) and (56).

7- The device for controlling the static alignment of rotating shafts, according to claim 6, is characterized by a sliding carriage and pivoting (41) respectively along and around the central rod (2). A comparator (31), fixed on the sliding carriage (41) by means of a rigid rod (10), makes it possible to record the radial and angular defects respectively around and along the outer surfaces of the hubs (1) and ( 33).

8- The device for controlling the static alignment of rotating shafts, according to claim 6, is characterized by two smooth buffer rings (39a, 39b) mounted on either side of the sliding carriage (41). The connections between the rings and hub bores are just slippery (very low clearance <0.01 mm). They make it possible to check the coaxiality of the shafts (validation of the perfect alignment of the shafts) when the carriage arrives at the end of the race as well on the right side as on the left side of the apparatus.

9- The device for controlling the static alignment of rotating shafts, according to claim 6, is characterized by two hubs (1) and (33) equipped, each with a bubble level gauge (31), adjustable by pivoting of the movable central part of the spirit level, thus allowing the layout of the motor and receiver systems to be controlled (horizontal, vertical or any). The level gauges are positioned and secured to the hubs (1) and (33) by the collars (32).

10- The device for controlling the static alignment of rotating shafts, according to claim 6, is characterized by a device for controlling the angular displacement of the two shafts to be controlled using the rods / needles (38a) and (38b). ). They are integrally linked to the central rod (2), on the side of the left spherical ball (36). The reading of the angular offsets is performed on a dial (57) graduated in degrees and fixed on a support plate (58). Any type of offset offset of the shafts and therefore the axes of the hubs, firstly in the vertical plane passing through the axis of the central rod is indicated by the vertical rod / needle (38a), arranged perpendicular to the axis of the central rod, and secondly in the horizontal plane, the offset defect is indicated by the radial needle rod (38b) which measures the pivot angle of the central rod about the vertical axis passing through the center of the left spherical ball (36).