JP3639396B2 - Rotor position adjustment method and rotor position adjustment apparatus for screw compressor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention has a male rotor and a female rotor in the casing, and both the rotors rotate while holding a predetermined minute gap by a timing gear fixed to each rotor with an interference fit. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for adjusting a position between a rotor of a screw compressor, and more particularly, to a method and an apparatus for adjusting a position between a rotor of a screw compressor that automatically makes a minute gap between both rotors desired. .
[0002]
[Prior art]
A conventional method for adjusting the position between the rotors of a screw compressor is disclosed in Japanese Patent Application Laid-Open No. 1-155089, in which at least one timing gear is not provided, and either one of the rotors is braked. Rotate the other rotor in both forward and reverse directions while applying a key, and use the rotational phase difference between the male and female rotors measured during the rotation to create a small gap between the two rotors. Setting (also referred to as timing adjustment or distribution adjustment).
[0003]
The setting of this minute gap is executed in the assembly process of the screw compressor. While restraining one timing gear, pressure oil is applied between the other timing gear and the rotor to which the timing gear is fixed. By loosening the interference fit between the two and hitting the tooth surface of the other timing gear with a hammer, the relative positional deviation between the other timing gear and the rotor to which the timing gear is fixed is reduced. Then, a shim (thickness gauge) is inserted between the rotors to check whether the minute gap between the rotors is the desired value (shim measurement), hammering and shim Repeating the measurement has been performed to make the minute gap between the rotors a desired value.
[0004]
[Problems to be solved by the invention]
In the above-mentioned prior art, since the minute gap between the rotors is manually set (distribution adjustment), not only does it take time for shim measurement, but also the hammer hit is affected by the skill level of the operator and the distribution adjustment is performed. There is a problem that the accuracy of the distribution is disturbed, the reliability of the distribution adjustment is low, and as a result, there is no rotor contact or compression performance.
[0005]
It is an object of the present invention to automatically set a minute gap between both rotors in a short time, and to ensure reliable distribution adjustment and excellent compression performance between the rotors of a screw compressor. It is to provide a position adjusting method.
[0006]
[Means for Solving the Problems]
A feature of the present invention that achieves the above object is that a pair of timings have a male rotor and a female rotor in the casing, and both the rotors are fixed to the respective rotors with an interference fit. In the position adjustment method between the rotors of the screw compressor that rotates while holding the minute gap with the gear, the minute gap between the two rotors is adjusted to a set value. The fixing by the interference fit with the rotor of the gear is loosened, and the torque based on the command value is intermittently applied to the rotor provided with the other timing gear via the servo motor. During intermittent torque application, a torque smaller than each torque applied intermittently above the static friction force in the drive system by the servomotor is applied in the forward and reverse directions, and the torque is applied in the forward and reverse directions. Relative position of both rotors Obtains an intermediate value, the intermediate value and the both Russia - in determining the command value of the intermittent torque application deviations from the next with a minute gap setting between data.
[0007]
Another feature of the present invention is that there are a male rotor and a female rotor in the casing, and these rotors hold a minute gap by a timing gear fixed to each rotor with an interference fit. In the rotor position adjusting device for adjusting the minute gap between the two rotors to a set value, the rotor of the other timing gear is restrained while restricting one timing gear. An intermittent torque applying means for loosely fixing the other timing gear and intermittently applying a torque based on the command value to the rotor provided with the other timing gear via a servo motor; Forward / reverse torque applying means for applying forward and reverse torque smaller than each torque intermittently applied to the servomotor during the application of static torque, which is greater than the static friction force in the drive system. The above when applying torque The relative position intermediate value calculating means for obtaining the intermediate value of the relative position of the rotor, and the difference between the intermediate value and the set value of the minute gap between the two rotors are then applied by the intermittent torque applying means. And an intermittent torque calculating means for obtaining a command value of the intermittent torque.
[0008]
According to the study by the present inventors, when assembling the screw compressor, while restraining one timing gear, pressure oil is applied between the other timing gear and the rotor to which the timing gear is fixed. Then, loosen the interference fit between the two, apply torque with a servo motor to the rotor on which the other timing gear is provided, and set the minute gap between the two rotors to the set value. When the servo is in effect, it is positioned at the target position (the minute gap is at the desired setting value), but when the servo is turned off, the minute gap between the rotors will deviate from the target position. Thus, it was confirmed that the screw compressor could not be assembled at a desired set value.
[0009]
The reason for this is that although pressure oil was applied between the other timing gear and the rotor to which the timing gear is fixed to loosen the interference fit between the other timing gear and the timing gear, There is still friction between the fixed rotor and a high tightening force, and when the servo motor is applying torque, the timing gear is fixed. The rotor is elastically deformed, so when the servo is cut, the elastic deformation is released to return to the original shape of the rotor, and the minute gap between the rotors is displaced from the target position. It is thought that it becomes.
[0010]
Therefore, a torque is intermittently applied to the rotor provided with the other timing gear via the servo motor, and the rotor is restored to its original shape while the torque is not applied. Based on this position, the following intermittent torque application was performed.
[0011]
In this case, the static frictional force in the servo motor system becomes the restraining force of the rotor that tries to return to its original shape, and the rotor does not return to its original shape. It was also confirmed that an error occurred between the desired fine gap between the two and the actual fine gap between the adjusted rotors.
[0012]
Therefore, during intermittent torque application, a torque smaller than each of the torques applied intermittently above the static friction force in the drive system by the servomotor is applied in the forward and reverse directions. In this case, an intermediate value of the relative positions of the two rotors is obtained. This intermediate value is equivalent to the intermediate value of the residual stress in the forward and reverse directions given to the rotor by the static friction force in the servo motor system, and the position of the rotor when it is not elastically deformed. Therefore, the other timing gear is provided by obtaining the next intermittent torque application command value from the deviation between this intermediate value and the desired minute gap (set value) between the two rotors. The rotor is not elastically deformed so that the minute gap between the two rotors becomes the target position, and the minute gap between the two rotors is automatically obtained in a short time. Thus, a screw compressor with high reliability of distribution adjustment and excellent compression performance can be obtained.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described according to an embodiment shown in the drawings.
FIG. 1 shows a block diagram of a screw compressor and a position adjustment device between the rotors. In FIG. 1, reference numeral 1 denotes a case of the screw compressor. The rotor 2 and the female rotor 3 are supported in the thrust direction and the radial direction via the ball bearings 4 and 5 and the roller bearings 6A, 6B, 7A and 7B. 8A, 8B, 9A, 9B are sealing, 10 is an oblique M timing gear fixed to the discharge side shaft end (upper end in FIG. 1) of the male rotor 2 by an interference fit, and 11 is a female rotor An oblique F timing gear fixed to the discharge side shaft end portion 3 (also the upper end in FIG. 1) with an interference fit, and 12 is an interference fit to the suction side shaft end portion (the lower end in FIG. 1) of the male rotor 2 Pinion gear fixed with
[0014]
During actual use of the screw compressor, the male rotor 2 and the M timing gear 10 are rotated by driving the pinion gear 12 by any means, and the F timing gear 11 is similarly driven by the M timing gear 10. The female rotor 3 rotates in the opposite direction to the male rotor 2. Although not shown, a bracket for receiving a thrust applied to the ball bearing 4 is attached to an end surface portion of the case 1 where both the timing gears 10 and 11 are provided. Furthermore, the screw compressor is usually installed horizontally, but in FIG. 1, the longitudinal direction is shown up and down for the sake of space.
[0015]
FIG. 2 shows a model of the minute gap between the rotor and the timing gear in the screw compressor shown in FIG. 1, where the M timing gear 10 and the F timing gear 11 are engaged with each other (the one-dot chain line circle Enlarged part is shown on the dot-and-dash line circle A, and the part where the male rotor 2 and female rotor 3 are engaged (the part indicated by the dashed-dotted line circle B) is enlarged and shown on the dashed-dotted line circle B ing. There is no gap B1 between the timing gears 10 and 11 on the forward side, and there is a gap B2 on the reverse side. Further, minute gaps G1 and G2 are set on the forward side and the reverse side of the rotors 2 and 3, respectively. The minute gaps G1 and G2 change by shifting the fixed position of the M timing gear 10 with respect to the male rotor 2.
[0016]
As to which position should be fixed, as described in Japanese Patent Laid-Open No. 1-155089, for example, the M timing gear 10 is removed from the male rotor 2, and the female rotor is connected via the F timing gear 11. The male rotor 2 is rotated in both forward and reverse directions while a brake is applied to the rotor 3, and the rotors 2, 3 are connected by the encoders 21, 22 connected to the rotors 2, 3 during the rotation. Is measured (this operation is called measurement operation). Then, by using this measurement result, the minute gaps G1 and G2 are obtained on the forward side and the reverse side of the rotors 2 and 3 so that a desired compression performance can be obtained, and M is set so as to be the target position. The timing gear 10 is fixed to the male rotor 2 with an interference fit (this operation is also called an adjustment operation).
[0017]
FIG. 3 shows a situation in which the minute gap between the rotor and the timing gear in the screw compressor is set to a desired distribution adjustment position.
[0018]
Returning to FIG. 1, reference numeral 23 denotes a gear for driving the pinion gear 12, and the drive gear 23 is rotated by a direct drive motor (hereinafter abbreviated as DD motor) 24 which is a servo motor. The DD motor 24 is installed on the lower end side of the male rotor 2 where the M timing gear 10 is not provided, and intermittently applies torque to the male rotor 2 via the pinion gear 12. A servo motor 25 restrains or brakes the F timing gear 11 through the gear 26.
[0019]
The inter-rotor position adjusting apparatus of the present invention is composed of a plurality of means having the following functions.
[0020]
(1) While restraining one timing gear, the other timing gear is loosened by an interference fit with the rotor, and the rotor provided with the other timing gear is connected via a servo motor. Intermittent torque applying means for intermittently applying a torque based on the command value (2) During the intermittent torque application, the torque is intermittently applied more than the static friction force in the drive system by the servo motor. Forward / reverse torque applying means (3) for applying a torque smaller than each torque forward and reverse Relative position intermediate value calculating means (4) for obtaining an intermediate value of the relative positions of the rotors when applying the forward and reverse torques Intermittent torque calculating means for obtaining a command value of an intermittent torque to be applied next by the intermittent torque applying means from a deviation between the intermediate value and a set value of a minute gap between the rotors;
[0021]
A plurality of means having the above functions can also be realized by a central control unit (hereinafter abbreviated as MPU) 30 and an inter-rotor position adjustment program stored and held in its memory.
[0022]
According to this inter-rotor position adjustment program, the output pulses of the encoders 21 and 22 connected to the rotors 2 and 3 are sent to the counter 33 via the interpolators 31 and 32 for dividing the output pulses. Then, the MPU 30 calculates the rotational phase difference between the rotors 2 and 3. Reference numeral 34 denotes a controller for rotating the DD motor 24 in both forward and reverse directions via a servo amplifier 35 during measurement work, and 36 denotes a DA conversion of a position command issued from the MPU 30 during adjustment work. The D / A converter 37 for driving the male rotor 2 so that the male rotor 2 has a desired gap with respect to the female rotor 3 by driving the DD motor 24, 37 during measurement work or adjustment work This DA converter converts the torque command output from the MPU 30 from DA to drive the servo motor 25 via the servo amplifier 38.
[0023]
Reference numeral 41 denotes a monitor that displays the processing status of the MPU 30, and 42 denotes a printer that outputs various data during measurement work or adjustment work as necessary. 51 is a press-fitting jig for loosening the interference fitting with the pressure oil sent from the hydraulic pump 53 via the pipe 52 to the M timing gear 10 fixed to the male rotor 2 at the time of measurement work or adjustment work, and 54 is the adjustment work. This is a jig for fixing (constraining) the M timing gear 10 to the casing 1 so that the M timing gear 10 does not rotate with respect to the male rotor 2 sometimes.
[0024]
Hereinafter, based on the flow of the embodiment of the software (rotor position adjustment program) of the present invention shown in FIG. 4, the position adjustment device of the screw compressor shown in FIG. A method for adjusting the position between the rotors will be described.
[0025]
First, in step (hereinafter abbreviated as “S”) 1, electric power such as encoders 21 and 22 and servo motors 24 and 25 are connected to a compressor body in which the M timing gear 10 is not fixed to the male rotor 2. Connect various devices. Next, measurement work is performed in S2.
[0026]
This measurement operation is performed by positioning control of the servo motor 24 using the controller 34. Details are as described in Japanese Patent Application Laid-Open No. 1-155089, and the description thereof is omitted.
[0027]
Next, after temporarily fixing the M timing gear 10 to the male rotor 2 by shrink fitting, the press-fitting jig 51 is attached to the discharge-side shaft end portion (upper end in FIG. 1) of the male rotor 2 (S3). ). The situation where the press-fitting jig 51 is fixed to the male rotor 2 is shown in FIG.
[0028]
In order to reach the situation of FIG. 5, the lower end screw portion of the piston 51 a in the press-fitting jig 51 is screwed to the upper end portion of the male rotor 2. Further, the cylinder 51 b of the press-fitting jig 51 is screwed to the M timing gear 10. Then, the pipe 52 is screwed to the upper end portion of the piston 51a. A hydraulic chamber 51c is defined by the M timing gear 10, the piston 51a, and the cylinder 51b. There is an introduction hole 51d communicating with the hydraulic chamber 51c from the upper end of the piston 51a, and pressure oil is supplied to the hydraulic chamber 51c from the hydraulic pump 53 shown in FIG. This pressure oil supply is S4 in FIG. 4, and the pressure oil in the hydraulic chamber 51c expands the inner diameter of the shrink fit portion of the M timing gear 10 with respect to the male rotor 2, and the M timing gear 10 in the hydraulic chamber 51c The M timing gear 10 and the cylinder 51b move downward relative to the male rotor 2 by the differential pressure between the downward hydraulic pressure applied to the end face and the upward hydraulic pressure applied to the end face of the cylinder 51b. The M timing gear 10 hits the ball bearing 4 to stop moving, and the shape shown in FIG. 5 is obtained.
[0029]
Since the M timing gear 10 and the F timing gear 11 are inclined teeth, they must rotate with each other along the inclined teeth when moving to the state shown in FIG. However, since the F timing gear 11 is fixed to the female rotor 3, when the M timing gear 10 rotates, the male and female rotors 2, 3 hit each other and stop rotating. For this reason, the M timing gear 10 rotates with respect to the male rotor 2, but between the contact points of the timing gears 10, 11 and the contact points of the rotors 2, 3 due to the mutual rotational friction force. Even if the twist occurs, the twist (strain) is not released by the frictional force even in the state of FIG. 5, and the strain remains.
[0030]
Next, the backlash between the timing gears 10 and 11, that is, the gap is measured in S5 of FIG. In this measurement, the male rotor 2 is restrained by the servo motor 24, the timing gear 11 is slightly driven by the servo motor 25, and the backlash with the timing gear 10 is detected by the encoder 21, 22 output pulse phase differences are obtained and calculated by the MPU 30.
[0031]
Since the gaps between the rotors 2 and 3 and the timing gears 10 and 11 can be measured at S2 and S4, the desired distribution positions as shown in FIG. 3, ie, G1 and G2, are given from the desired compression performance. Thus, the adjustment work is started so that the positional relationship between the rotors 2 and 3 as the gaps G1 and G2 is obtained.
[0032]
As preparation for adjustment work, the timing gear 10 is fixed to the casing 1 by using the fixing jig 54 shown in FIG.
[0033]
In the adjustment operation, torque control of the servo motor 24 is performed via the DA converter 36 in S7. At this time, the F timing gear 11 is restrained by contacting the timing gears by applying torque in one direction by the servo motor 25 so that the timing gear 11 does not rotate between backlashes of the timing gear.
[0034]
Next, torque control of the servo motor 24 will be described in detail.
FIG. 6 shows a situation in which the interference fit fixing between the M timing gear 10 and the male rotor 2 is loosened, and the present inventors obtained from an experiment. In FIG. 6, the horizontal axis represents the hydraulic pressure applied from the hydraulic pump 53 to the hydraulic chamber 51c shown in FIG. 5, and the vertical axis represents the rotational torque applied to the male rotor 2 by the DD motor 24 shown in FIG. The mutual rotation torque of the M timing gear 10 with respect to the hydraulic pressure at which the M timing gear 10 starts rotating against the frictional force with the male rotor 2 is shown.
[0035]
That is, although the hydraulic pressure is applied to the hydraulic chamber 51c and the interference fit between the M timing gear 10 and the male rotor 2 is loosened, there is friction between the M timing gear 10 and the male rotor 2. It can be seen that a high tightening force is generated and the male rotor 2 is elastically deformed by the rotation of the M timing gear 10 due to the tightening force. Further, a static frictional force exists between the ball bearing 4 and the roller bearings 6A and 6B and the male rotor 2 and between the male rotor 2 and the DD motor 24.
[0036]
Based on this fact, in the present invention, torque is applied intermittently (stepped) to the male rotor 2 by the DD motor 24 as shown in FIG. The torque command value V is intermittently greater than the static friction force in the drive system or the like during the gap distribution target (target position) between the rotors 2 and 3 for each screw compressor and intermittent torque application. Deviation from the intermediate value of the relative position of both rotors when forward and reverse torque ((b), (c) in FIG. 7) smaller than each applied torque ((a) in FIG. 7) is applied Further, it is determined by calculating the characteristic curve shown in FIG.
[0037]
FIG. 8 shows the rotational movement (displacement) of the male rotor 2 when torque is intermittently applied as shown in FIG. In the figure, the curve θ1 is the difference between the detection results of the encoder 21 and the encoder 22, and the curve θ2 is the male rotor when the elastic deformation is released and the rotation returns in the male rotor 2. The displacement of 2 is indicated by an envelope.
[0038]
In FIG. 8, (d) is the rotational movement (displacement) of the male rotor 2 corresponding to the intermittently applied torque (a), and (e) and (f) are forward and reverse torques (b) and (c), respectively. Is the rotational movement of the male rotor 2 corresponding to. (I) is an intermediate value between the rotational movements (e) and (f) of the male rotor 2.
[0039]
After applying torque intermittently, the intermediate value (i) is obtained from the outputs of the encoders 21 and 22 in the MPU 30 in S8 of FIG. 4, and the target value is determined from the displacement of the male rotor 2 obtained by the curve θ2. It is confirmed whether or not the distribution position has been reached. If the target distribution position has not been reached, the intermediate value (i) is used as a reference, that is, the deviation is applied next from the position of the male rotor 2 and the target position. The torque command value to be calculated is calculated. Then, returning to S7, the next intermittent torque is applied. Therefore, as shown by the curve θ2, the male rotor 2 is driven to the target position along with intermittent torque application and forward / reverse torque application. In addition, the dotted line of FIG. 7 has shown the tolerance | permissible_range with respect to a target position. If it is determined in S8 of FIG. 4 that the male rotor 2 has entered the allowable range and has reached the target position, the process proceeds to S9. By repeating S7 and S8, the gap B1 + B2 in FIG. 3 is accommodated in the gap G1 + G2, and as a result, between the rotors 2 and 3, between the timing gears 10 and 11, and between the male rotors 2 and M. All the distortions generated in S4 between the timing gears 10 are released.
[0040]
Note that the torque command value to be applied next is calculated based on the displacement when the target distribution position has not been reached in S7, and whether the target distribution position is reached from the displacement of the male rotor 2 in S8. Only confirmation may be made. In this case, since it is empirically known how many times intermittent application of torque is performed, it is sufficient for the operator to specify the timing for shifting to S8 in advance. And when it returns to S7 from S8, it should just move to S8 whenever it processes S7 once.
[0041]
In S9, the press-fitting jig 51 and the fixing jig 54 shown in FIG. 1 are removed, and the process proceeds to S10, and the timing gear gap (backlash) is measured again.
[0042]
In this measurement, the distortion that may have occurred between the M timing gear 10 and the F timing gear 11 or the male rotor 2 when the M timing gear 10 is fixed in S4d in S5 or S7 is released. Since the rotors 2 and 3 are assigned to the target positions, the space between the M timing gear 10 and the F timing gear 11 is free. Therefore, both the M and F timings are used in the same manner as the measurement method in S5. The gap between the gears 10 and 11 is measured.
[0043]
Then, in S11, the final allocation target position is determined again from the measurement results in S2 and S10 by the MPU 30, and the press-fitting jig 51 is provided again in S12. Pressure oil is supplied to loosen the interference fit with the male rotor 2. Although not shown here, the timing gear backlash measurement is performed in the same manner as in S5 and S6, the M timing gear 10 is fixed to the casing 1 with the fixing jig 54, and the same processing as S7 and S8 is performed in S14 and S15. Then, both rotors 2 and 3 are set as the final distribution target positions determined in S11.
[0044]
Finally, in S16, the press-fitting jig 51 and the fixing jig 54 are removed, and the M timing gear 10 is fitted and fixed to the male rotor 2 so that the M and F timing gears 10 and 11 for confirmation are connected. The gap measurement is performed in S17. If necessary, the hard copy is taken by the printer 42 in S18, the adjusting devices such as the encoders 21 and 22 are removed in S19, and the series of processes is completed.
[0045]
As described above, the position adjustment between the rotors can be automatically performed by the MPU 30 apart from the attachment / detachment of the press-fitting jig 51 and the fixing jig 54, and in a state without elastic deformation.
[0046]
In S7 and S14 of FIG. 4, in FIG. 7, the forward / reverse torque is applied in the reverse direction (c) after the forward torque application (b). Since the intermediate value (i) of the rotational movements (e) and (f) of the motor 2 is obtained, the reverse direction torque application (c) may be preceded and the forward direction torque application (b) may be subsequent. .
[0047]
【The invention's effect】
As described above, according to the present invention, a screw compressor that can automatically make a minute gap between both rotors desired in a short time, has high reliability of distribution adjustment, and has excellent compression performance. Can be obtained.
[Brief description of the drawings]
FIG. 1 is a block diagram of an inter-rotor position adjusting device for a screw compressor according to an embodiment of the present invention.
FIG. 2 is a model diagram showing a state of a minute gap between a rotor and a timing gear in the screw compressor shown in FIG.
3 is a view showing a situation in which a minute gap between a rotor and a timing gear is set to a desired distribution adjustment position in the screw compressor shown in FIG. 1. FIG.
FIG. 4 is a software flow diagram of a position adjustment process between rotors of a screw compressor according to an embodiment of the present invention.
FIG. 5 is a diagram showing a situation in which the fixation by the interference fitting with the rotor of the other timing gear is loosened in the soft flow shown in FIG. 4;
6 is a view for explaining a situation in which the fixation by the interference fit with the rotor of the other timing gear shown in FIG. 5 is loosened. FIG.
7 is a diagram for explaining a situation in which torque is intermittently applied to a rotor provided with the other timing gear via a servo motor in the soft flow of FIG. 4;
8 is a diagram showing the relationship between the position of the rotor where the other timing gear is provided and its target position in the intermittent torque application shown in FIG. 7; FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Casing, 2 ... Male rotor, 3 ... Female rotor, 4, 5 ... Ball bearing, 6A, 6B, 7A, 7B ... Roller bearing, 8A, 8B, 9A, 9B ... -Ring, 10 ... M timing gear, 11 ... F timing gear, 12 ... Pinion gear, 21, 22 ... Encoder, 23 ... Drive gear, 24 ... DD motor, 25 ... Servo motor, 26 ... Gear , 30 ... MPU, 31, 32 ... Interpolator, 33 ... Counter, 34 ... Controller, 35, 38 ... Servo amplifier, 36, 37 ... DA converter, 41 ... Monitor, 42 ... Printer, 51 ... Press-fit jig, 51a ... Piston, 51b ... Cylinder, 51c ... Hydraulic chamber, 51d ... Introduction hole, 52 ... Piping, 53 ... Hydraulic pump, 54 ... Fixing jig

Claims (5)

A screw which has a male rotor and a female rotor in the casing, and these rotors rotate while holding a minute gap by a pair of timing gears fixed to the respective rotors with an interference fit. In the method for adjusting the position between the rotors of the compressor, the minute gap between the two rotors is adjusted to a set value.
While restraining one timing gear, loosen the other timing gear by tightening it with the rotor, and set the other timing gear to the command value via the servo motor. Torque is applied intermittently, and during the intermittent torque application, torque smaller than each torque applied intermittently above the static friction force in the drive system by the servo motor is forward and reverse. The intermediate value of the relative positions of the two rotors when applying the torque in the forward and reverse directions is obtained, and the next value is determined from the deviation between the intermediate value and the set value of the minute gap between the two rotors. A method for adjusting a position between rotors of a screw compressor, wherein a command value for intermittent torque application is obtained. 2. The screw compressor rotor adjusting method according to claim 1, wherein the forward / reverse torque is applied by applying the forward torque after applying the reverse torque. Position adjustment method. 2. The method of adjusting the position between the rotors of a screw compressor according to claim 1, wherein intermittent torque application and forward / reverse torque application are provided by the timing gear of the rotor provided with the other timing gear. A method for adjusting a position between rotors of a screw compressor, wherein the position is applied to an end opposite to the end of the screw compressor. In the method for adjusting the position between the rotors of the screw compressor according to claim 1, when the torque is intermittently applied to the rotor provided with the other timing gear via the servo motor, A method of adjusting a position between rotors of a screw compressor, wherein the other timing gear is restrained. The screw compressor has a male rotor and a female rotor in the casing, and both the rotors rotate while holding a minute gap by a timing gear fixed to each rotor with an interference fit. In the inter-rotor position adjusting device for adjusting the minute gap between the two rotors to a set value,
While restraining one timing gear, loosen the other timing gear by tightening it with the rotor, and set the other timing gear to the command value via the servo motor. Intermittent torque application means for intermittently applying a torque based on the torque;
A forward / reverse torque applying means for applying forward and reverse torque smaller than each torque intermittently applied at or above the static friction force in the drive system by the servomotor during the intermittent torque application;
A relative position intermediate value calculating means for obtaining an intermediate value of the relative positions of the two rotors when applying the forward and reverse torques;
Intermittent torque calculating means for obtaining a command value of the intermittent torque to be applied next by the intermittent torque applying means from the deviation between the intermediate value and the set value of the minute gap between the rotors. An apparatus for adjusting a position between rotors of a screw compressor.

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