Eccentricity calibration system for crankshaft grinding machine

Abstract

The application discloses an eccentricity calibration system for a crankshaft grinding machine, comprising: a sensing block arranged at a first end of a counterweight guide rail of a support driven by a motor; four sensing switches fixed on a support body of the support; and a processor configured to calculate a motor output torque measured when the sensing block rotates through the four sensing switches under the condition that a counterweight is installed at a central position of the counterweight guide rail, and adjust the position of the counterweight on the counterweight guide rail based on the measured motor output torque to compensate for the eccentricity of the crankshaft. With the eccentricity calibration system of the application, the eccentricity of the crankshaft can be quickly judged and adjusted to improve work efficiency; the system can be integrated on an existing device structure, and has small mechanical modification workload, easy operation, convenience, low manufacturing cost and high accuracy; and the system can be expanded to other similar devices to accurately judge eccentricity problems, thereby improving the machining precision of the crankshaft, reducing mechanical loss and prolonging the service life of the device.

Description

Technical Field

[0001] This invention relates to an eccentricity calibration system, and more particularly to an eccentricity calibration system for crankshaft grinding machines. The invention is intended for use in the matching and adjustment applications for machining large crankshafts, where "large" refers to workpieces weighing up to five tons and measuring up to four meters in length. Background Technology

[0002] In existing eccentricity calibration systems for crankshaft grinding machines, counterweights with adjustable positions are typically added to both sides of the two supports of the crankshaft grinding machine (i.e., the headstock and tailstock). The eccentric torque caused by crankshaft eccentricity is reduced by manually adjusting the position of the counterweights.

[0003] This type of eccentric calibration for large crankshaft grinding machines relies on the operator's experience. The operator manually rotates the crankshaft and judges whether dynamic balance has been achieved by observing whether the rotating crankshaft can stop freely at any position. Summary of the Invention

[0004] In view of this, in order to eliminate or mitigate the above problems, the present invention discloses an eccentric calibration system for a crankshaft grinding machine, the crankshaft grinding machine comprising two supports spaced apart from each other, each of the two supports comprising a fixed support body and a support rotating part rotatably connected to the support body, the support rotating part comprising a circular counterweight support turntable and a crankshaft support turntable spaced apart from each other and coaxially arranged, and a support rotating shaft fixing the counterweight support turntable and the crankshaft support turntable together, the rotation axes of the two support rotating parts being coincident with each other, the crankshaft grinding machine being configured in use such that the crankshaft to be processed is fixed to the two supports. The crankshaft support turntable rotates together with the two bracket rotating parts; each of the two brackets further includes a counterweight, the counterweight being configured to be mounted to and fixed at any position on a counterweight guide rail disposed diametrically on the counterweight support turntable, the two counterweight guide rails being parallel to each other and each counterweight guide rail including a first end and a second end opposite each other, the first end and the second end being located on the circumference of the counterweight support turntable, the counterweight guide rails being parallel to the vertical direction in the initial position of the crankshaft installation and the first end being located above the second end, the center of mass of the crankshaft being located on the counterweight support turntable. The projection point is located on the counterweight guide rail. The eccentricity calibration system comprises: a sensing block disposed at the first end of the counterweight guide rail of one of the two supports, the one of the two supports being driven by a motor; and four inductive switches fixed to the support body of the one support and located in the same plane perpendicular to the rotation axis, the plane being parallel to the plane where the counterweight support turntable of the one support is located, the four inductive switches being located on the circumference of a virtual circle centered on the rotation axis, and connecting the first inductive switch and the third inductive switch. The first virtual connection line of the inductive switch is parallel to the vertical direction and passes through the center of the virtual circle. The first inductive switch is located above the third inductive switch. The second virtual connection line connecting the second and fourth inductive switches of the four inductive switches is perpendicular to the vertical direction and passes through the center of the virtual circle. The processor is configured to: calculate the motor output torque measured when the inductive block rotates through the four inductive switches with the counterweight installed at the center position of the counterweight guide rail, and adjust the position of the counterweight on the counterweight guide rail based on the measured motor output torque to compensate for the eccentricity of the crankshaft.

[0005] Furthermore, the processor is also configured to: obtain a graph consisting of four curves representing the output torque of the motor at the four inductive switches relative to the rotational speed by gradually increasing the rotational speed of the motor; and adjust the position of the counterweight on the counterweight guide rail based on the obtained graph, and calculate a graph with the counterweight installed in the current position, until the four curves substantially overlap in the graph.

[0006] Furthermore, the processor is configured to: in a curve calculated when the counterweight is installed at the center position of the counterweight guide rail, if the motor output torques at the four inductive switches at the same rotation speed differ significantly and the motor output torque at the first inductive switch is the largest and the motor output torque at the third inductive switch is the smallest, then adjust the position of the counterweight towards the second end of the counterweight guide rail.

[0007] Furthermore, the processor is configured to: in a curve calculated when the counterweight is installed at the center position of the counterweight guide rail, if the motor output torques at the four inductive switches at the same rotation speed differ significantly and the motor output torque at the first inductive switch is the smallest and the motor output torque at the third inductive switch is the largest, then adjust the position of the counterweight towards the first end of the counterweight guide rail.

[0008] Furthermore, the processor is configured to: when calculating the curves for the counterweights installed in various positions, increase the rotational speed in increments of 100 RPM starting from 0, until the maximum design speed of the motor is reached.

[0009] Furthermore, the processor is configured to rotate the support rotating part of the bracket at least 10 revolutions after each increase in rotational speed to reach a stable speed.

[0010] Furthermore, the processor is configured to select 2n+1 special positions on the counterweight guide rail to divide the counterweight guide rail into 2n equal-length position intervals, where n is a positive integer.

[0011] Furthermore, the processor is configured to: after determining a graph of the four curves that substantially overlap for the crankshaft, store the location range of the counterweight to establish a database about the crankshaft type and the location of the counterweight.

[0012] Furthermore, the processor is also configured to: add the motor output torque at the four inductive switches measured at the same rotational speed to a Cartesian coordinate system with the center of the virtual circle as the origin and the first virtual line and the second virtual line as the coordinate axes to simulate a torque virtual circle, thereby obtaining a torque distribution roundness map; and determine the position of the counterweight towards the first end or the second end of the counterweight guide rail based on the roundness of the torque virtual circle and the degree of deviation of the center of the torque virtual circle relative to the origin.

[0013] Furthermore, the torque distribution roundness diagram includes multiple virtual torque circles simulated at multiple different speeds.

[0014] As can be seen from the above solution, the arrangement proposed in this invention can quickly determine and adjust the crankshaft eccentricity to improve work efficiency; it can be integrated into the existing equipment structure, requiring little mechanical modification work, is easy to operate, and is convenient and quick; it has low manufacturing cost and high accuracy; and it can be extended to other similar equipment to accurately determine eccentricity problems, thereby improving crankshaft machining accuracy, reducing mechanical wear, and increasing equipment service life. Attached Figure Description

[0015] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which will make the above and other features and advantages of the present invention more apparent to those skilled in the art. In the drawings:

[0016] Figure 1 This is a schematic side view showing a crankshaft grinding machine according to an embodiment of the present invention;

[0017] Figure 2 It shows Figure 1 A schematic side view of a crankshaft grinding machine, wherein the crankshaft to be processed is mounted on the crankshaft grinding machine;

[0018] Figure 3 Details of the support and a portion thereof for a crankshaft grinding machine according to an embodiment of the present invention are shown;

[0019] Figure 4 This is a schematic side view showing an eccentric calibration system according to an embodiment of the present invention, wherein the eccentric calibration system is mounted on a motor-driven bracket of a crankshaft grinding machine;

[0020] Figure 5 It shows Figure 4 A schematic side view of an eccentric calibration system, which exemplarily shows several specific positions on the counterweight guide rail;

[0021] Figure 6 It shows a graph obtained in Experiment 1, consisting of four curves representing the motor output torque relative to the rotational speed at the four inductive switches.

[0022] Figure 7 This is a graph showing the output torque of the motor at the four inductive switches relative to the rotational speed, obtained in Experiment 2.

[0023] Figure 8 This is a graph showing the output torque of the motor relative to the rotational speed at the four inductive switches, obtained in Experiment 3.

[0024] Figure 9 It shows a graph obtained in Experiment 4, consisting of four curves representing the motor output torque relative to the rotational speed at the four inductive switches.

[0025] Figure 10 This shows the roundness diagram of the torque distribution obtained in Experiment 5;

[0026] Figure 11 This shows the roundness diagram of the torque distribution obtained in Experiment Six; and

[0027] Figure 12 An exemplary user interface on the output device of an eccentric calibration system according to an embodiment of the present invention is shown.

[0028] The reference numerals in the attached figures are as follows:

[0029] 100 Crankshaft Grinding Machine

[0030] 200 crankshaft

[0031] 1. Bracket

[0032] 10 Eccentricity Calibration System

[0033] 11. Support body

[0034] 12. Rotating part of the bracket

[0035] 121 Counterweight supporting turntable

[0036] 122 Crankshaft Support Turntable

[0037] 13 counterweights

[0038] A. Rotation axis

[0039] B Induction Block

[0040] C1 Virtual Circle

[0041] C2 Torque Virtual Circle

[0042] G counterweight guide rail

[0043] G1 First End

[0044] G2 Second End

[0045] S1 First Inductive Switch

[0046] S2 Second Inductive Switch

[0047] S3 Third Inductive Switch

[0048] S4 Fourth Inductive Switch

[0049] Torque at the first sensor switch T1

[0050] Torque at the second sensor switch T2

[0051] Torque at the third sensor switch of T3

[0052] Torque at the fourth sensor switch of T4 Detailed Implementation

[0053] To make the objectives, technical solutions, and advantages of this invention clearer, the following embodiments are provided to further illustrate the invention in detail. The nouns and pronouns referring to "person" in this patent application are not limited to specific genders.

[0054] Combination Figures 1 to 5 As shown, the present invention discloses an eccentricity calibration system 10 for a crankshaft grinding machine 100, wherein combined with Figures 1 to 3 A crankshaft grinding machine 100 and its components are schematically shown, and combined with Figure 4 and Figure 5 An eccentricity calibration system 10 is shown mounted thereon.

[0055] like Figure 1 and Figure 2 As best shown, the crankshaft grinding machine 100 may include two supports 1 spaced apart from each other, namely a headstock and a tailstock. The two supports 1 have substantially the same structure and are arranged aligned with each other.

[0056] like Figure 1 As best shown, each of the two supports 1 may include a fixed support body 11 and a support rotating part 12 rotatably connected to the support body 11. Typically, the support body 11 is fixed to the ground or other flat mounting surface.

[0057] The support rotation section 12 may include a circular counterweight support turntable 121 and a crankshaft support turntable 122 arranged coaxially and spaced apart from each other, and a support shaft (not shown) that fixes the counterweight support turntable 121 and the crankshaft support turntable 122 together. The support shaft extends along the rotation axis A of the support rotation section 12, thereby realizing the synchronous rotation of the counterweight support turntable 121 and the crankshaft support turntable 122 about the rotation axis A.

[0058] Furthermore, since the two supports 1 are arranged aligned with each other, the rotation axes A of the rotating parts 12 of the two supports coincide, with the crankshaft support turntables 122 facing each other. The crankshaft grinding machine 100 is configured such that, in use, the crankshaft 200 to be processed is fixed between the two crankshaft support turntables 122 of the two supports 1 to rotate together with the rotating parts 12 of the two supports. In use, one of the two supports 1 (i.e., the headstock or tailstock) is driven by a motor, while the other support is driven.

[0059] Each of the two supports 1 may further include a counterweight 13, which is configured to be mounted to and fixed at any position on a counterweight guide rail G (e.g., a dovetail guide rail) disposed diametrically on a counterweight support turntable 121. The two counterweight guide rails G are parallel to each other; that is, regardless of any rotational position, the two counterweight guide rails G on the two supports 1 are parallel to each other. The counterweight guide rail G includes a first end G1 and a second end G2 opposite to each other, both located on the circumference of the counterweight support turntable 121; in other words, the counterweight guide rail G extends along the full diameter of the counterweight support turntable 121. In the initial position for mounting the crankshaft 200, the counterweight guide rail G is parallel to the vertical direction, with the first end G1 above the second end G2, and the projection of the center of mass of the crankshaft 200 onto the counterweight support turntable 121 is located on the counterweight guide rail G. It should be noted that there are specific requirements for the installation of crankshaft 200 in this field. When installing crankshaft 200, the counterweight guide rail G is in an upright state. Crankshaft 200 usually has a structure that is mirror-symmetrical with respect to the mid-longitudinal section, so that the center of mass of crankshaft 200 after installation is located in the virtual plane where the counterweight guide rail G and the axis of rotation A are located. Such specific requirements are known in this field and will not be elaborated here.

[0060] like Figure 4 and Figure 5 As best shown, the eccentricity calibration system 10 may include a sensing block B, four sensing switches (i.e., a first sensing switch S1, a second sensing switch S2, a third sensing switch S3, and a fourth sensing switch S4) and a processor.

[0061] The sensing block B can be set at the first end G1 of the counterweight guide rail G of one of the two supports 1, and the one of the two supports 1 is driven by a motor.

[0062] All four inductive switches can be fixed to the support body 11 of the bracket and are located in the same plane perpendicular to the rotation axis A. This plane is parallel to the plane where the counterweight support turntable 121 of the bracket is located. The four inductive switches are located on the circumference of a virtual circle C1 centered on the rotation axis A, as shown in the reference. Figure 4A circle is drawn with a dashed line in the middle. The first virtual line connecting the first sensor switch S1 and the third sensor switch S3 is parallel to the vertical direction and passes through the center of the virtual circle C1. The first sensor switch S1 is located above the third sensor switch S3. The second virtual line connecting the second sensor switch S2 and the fourth sensor switch S4 is perpendicular to the vertical direction and passes through the center of the virtual circle C1. From Figure 4 From the perspective of the first virtual connection line, in the initial position of the crankshaft 200, the extension direction of the first virtual connection line coincides with that of the counterweight guide rail G, and the sensing block B is adjacent to the first sensing switch S1.

[0063] The processor can be configured to calculate the center position of the counterweight 13 mounted on the counterweight guide rail G (e.g., Figure 5 The motor output torque is measured when the sensing block B rotates through four sensing switches at the position shown (P0). Based on the measured motor output torque, the position of the counterweight block 13 on the counterweight block guide rail G is adjusted to compensate for the eccentricity of the crankshaft 200, so that the crankshaft grinding machine can achieve the smoothest possible rotation.

[0064] In a first embodiment of the invention, the processor may further be configured to: obtain a graph consisting of four curves representing the motor output torque versus the rotational speed at the four inductive switches by gradually increasing the motor speed; and adjust the position of the counterweight 13 on the counterweight guide rail G based on the obtained graph, and calculate the graph with the counterweight 13 installed in the current position, until the four curves substantially overlap in the graph. In the graph, if the four curves representing the motor output torque versus the rotational speed differ significantly, for example, exceeding the user-set maximum speed torque allowable deviation, it indicates a significant eccentricity problem; while if the four curves substantially overlap, it indicates that the counterweight 13 is in the optimal eccentricity compensation position, under which the crankshaft grinding machine can achieve smooth rotation.

[0065] Specifically, the processor can also be configured to: in a curve calculated with the counterweight 13 installed at the center of the counterweight guide rail G, if the motor output torques at the four inductive switches at the same rotational speed differ significantly (e.g., exceeding the user-set maximum speed torque allowable deviation), and the motor output torque at the first inductive switch S1 is the largest and the motor output torque at the third inductive switch S3 is the smallest, then the position of the counterweight 13 is adjusted towards the second end G2 of the counterweight guide rail G; conversely, if the motor output torques at the four inductive switches at the same rotational speed differ significantly, and the motor output torque at the first inductive switch S1 is the smallest and the motor output torque at the third inductive switch S3 is the largest, then the position of the counterweight 13 is adjusted towards the first end G1 of the counterweight guide rail G. Based on this principle, the optimal eccentricity compensation position of the counterweight 13 can be obtained by gradually adjusting the position of the counterweight 13 on the counterweight guide rail G in an appropriate direction based on the results obtained from the curve.

[0066] Preferably, the processor can also be configured to: when calculating the curves for the counterweight 13 installed in various positions, increase the rotational speed in increments of 100 RPM starting from 0, until the maximum design speed of the motor is reached. Furthermore, the processor can also be configured to: after each increase in rotational speed to reach a stable speed, rotate the support rotating part 12 of the bracket 1 at least 10 revolutions. For example, the motor output torque when the sensing block B passes each sensing switch can be collected separately by a PLC program, and all collected torque values ​​can be processed using the mean filtering principle. This method of obtaining motor output torque is known in the art and will not be described further here.

[0067] Furthermore, the processor can also be configured to select 2n+1 special positions on the counterweight guide rail G to divide the counterweight guide rail G into 2n equal-length position intervals, where n is a positive integer. When n=1, the three special positions selected on the counterweight guide rail G are the center position of the counterweight guide rail G and the two end positions on either side of the center position where the counterweight 13 can move. These two end positions can be the first end G1 and the second end G2 of the counterweight guide rail G, or they can be positions radially inward of the first end G1 or the second end G2. In any case, the distance from these two end positions to the center position is equal. Thus, when n=1, the counterweight guide rail G is divided into two equal-length position intervals. Furthermore, as... Figure 5As shown, exemplarily illustrating the case where n=2, the five specific positions selected on the counterweight guide rail G are: the center position P0 of the counterweight guide rail G; the two end positions P1 and P4 on either side of the center position P0; the center point P2 that divides the center position P0 and the end position P1; and the center point P3 that divides the center position P0 and the end position P4. Thus, in the case of n=2, the counterweight guide rail G is divided into four equally long position intervals. This pattern continues when n is greater than 2. The processor can also be configured to: after determining a graph of four substantially overlapping curves for a specific crankshaft, store the position intervals where the counterweight is located to establish a database of crankshaft types and counterweight positions. Accordingly, for a specific type of crankshaft, the database can guide the user to quickly find the precise position interval where the counterweight needs to be placed, and the more subdivided the counterweight guide rail G (i.e., the larger n is), the more accurate the range of position intervals.

[0068] The following will refer to Figures 6 to 9 The principles of the invention are detailed by the results of the four experiments shown (i.e., Experiment 1, Experiment 2, Experiment 3, and Experiment 4), where the torque at the first inductive switch, the torque at the second inductive switch, the torque at the third inductive switch, and the torque at the fourth inductive switch are shown as T1, T2, T3, and T4, respectively.

[0069] In corresponding Figure 6 In Experiment 1, the crankshaft grinding machine was unloaded without a crankshaft installed, and the counterweight 13 was located at the center position P0. From Figure 6 As shown in the curve graph, the motor output torque gradually increases with the increase of speed. The motor output torque at the four induction switches at the same speed is relatively close, that is, the four curves basically overlap. This indicates that the center position P0 of the counterweight 13 is approximately the center of mass of the rotating part 12 of the bracket, and at this time, a smooth rotation can be achieved.

[0070] In corresponding Figure 7 In Experiment 2, the crankshaft grinding machine was unloaded without a crankshaft installed, and counterweight 13 was located at the end position P1. From Figure 7 The curves shown indicate that the motor output torque gradually increases with the increase of speed. The motor output torque at the four sensor switches at the same speed differs significantly, meaning that the four curves differ considerably. The motor output torque at the first sensor switch S1 is the largest, while the motor output torque at the third sensor switch S3 is the smallest. This indicates that there is a relatively serious eccentricity, and the crankshaft grinding machine is not suitable for processing because the rotation will be unstable.

[0071] In corresponding Figure 8 In Experiment 3, a crankshaft grinding machine was loaded with a crankshaft, which was eccentric, and the counterweight 13 was located at the center position P0. From Figure 8 The curves shown indicate that the motor output torque at the four sensor switches differs significantly at the same rotational speed; that is, the four curves show considerable differences. The motor output torque is highest at the first sensor switch S1 and lowest at the third sensor switch S3. This suggests that the crankshaft's center of gravity is biased towards the end position P1. Therefore, the position of the counterweight 13 needs to be adjusted towards the end position P4. Furthermore, actual observation also shows that the crankshaft's main journal centerline is close to the end position P1, which matches the results in the curves.

[0072] In corresponding Figure 9 In Experiment 4, a crankshaft grinding machine was loaded with a crankshaft. The crankshaft itself was eccentric. Compared to Experiment 3, the position of counterweight 13 was adjusted towards the end position P4 to ultimately obtain... Figure 9 The results are shown. From Figure 9 The curves shown show that the motor output torque at the four induction switches at the same speed is relatively close, meaning that the four curves basically overlap. This is very close to the result of Experiment 1, indicating that at the location of counterweight 13, the eccentricity is adjusted or compensated, enabling smooth rotation.

[0073] The results of experiments one through four show that the curves formed by the motor output torque relative to the rotational speed at the four induction switches can indicate whether the position of the counterweight 13 is appropriate. The closer the four curves overlap, the better the counterweight 13 is adjusted.

[0074] In a second embodiment of the invention, the processor may further be configured to: add the motor output torque measured at the four inductive switches at the same rotational speed to a Cartesian coordinate system with the center of the virtual circle C1 as the origin and the first virtual line and the second virtual line as the coordinate axes to simulate a virtual torque circle C2, thereby obtaining a torque distribution roundness diagram; and determine the position of the counterweight 13 toward the first end G1 or the second end G2 of the counterweight guide rail G based on the roundness of the virtual torque circle C2 and the degree of deviation of the center of the virtual torque circle C2 from the origin. Specifically, the torque distribution roundness diagram includes multiple virtual torque circles C2 simulated at multiple different rotational speeds.

[0075] For example in Figure 10 or Figure 11The figure exemplifies two virtual torque circles C2 in a Cartesian coordinate system, representing the motor output torque at four inductive switches measured at 100 RPM and 1600 RPM. The smaller virtual circle C2 corresponds to 100 RPM and the larger virtual circle C2 corresponds to 1600 RPM. The dashed lines represent the circles approximated by the corresponding virtual torque circles C2, whose centers are approximately equal to the center of the corresponding virtual torque circles C2, representing the torque center, indicated by solid dots in the figure. The × symbol in the figure represents the rotation center.

[0076] The following will refer to Figures 10 to 11 The principles of the invention are detailed by the results of the two experiments shown (i.e., Experiment 5 and Experiment 6).

[0077] In corresponding Figure 10 In Experiment 5, the crankshaft grinding machine was unloaded without a crankshaft, and the counterweight 13 was located at the center position P0. The motor output torque at four inductive switches was recorded for each revolution at the same speed. At 100 RPM, the motor output torques measured at the first inductive switch S1 to the fourth inductive switch S4 were 0.7 Nm, 0.7 Nm, 0.8 Nm, and 0.6 Nm, respectively; while at 1600 RPM, the motor output torques were 3.6 Nm, 3.5 Nm, 3.3 Nm, and 3.5 Nm, respectively. Figure 10 As shown in the torque distribution roundness diagram, the roundness of the virtual torque circle C2 is good, and the center of the virtual torque circle C2 (i.e., the torque center) basically coincides with the origin of the rectangular coordinate system (i.e., the rotation center). This indicates that the center position P0 of the counterweight 13 is approximately the center of mass of the rotating part 12 of the bracket, and a smooth rotation can be achieved at this time.

[0078] In corresponding Figure 11 In Experiment Six, the crankshaft grinding machine was unloaded without a crankshaft, and counterweight 13 was positioned at the end point P1. The motor output torque at four inductive switches was recorded during one revolution at the same speed. Figure 11 As shown in the torque distribution roundness diagram, the roundness of the virtual torque circle C2 is poor, and the center of the virtual torque circle C2 deviates from the origin of the rectangular coordinate system in the direction of the first inductive switch S1. This indicates that there is a relatively serious eccentricity, and the crankshaft grinding machine is not suitable for processing because the rotation will be unstable.

[0079] Based on this principle, when the crankshaft grinding machine is under load, the inspection can begin with the counterweight 13 placed at the center position P0. The roundness of the torque virtual circle C2 and the degree of deviation of the center of the torque virtual circle C2 from the measured torque distribution roundness diagram can be visually determined. Based on this, it can be determined whether the position of the counterweight 13 needs adjustment, and whether the adjustment should be towards the first end G1 or the second end G2 of the counterweight guide rail G, until a similar result is obtained. Figure 10 The result of the torque distribution roundness diagram.

[0080] Similar to the first embodiment, a database of crankshaft types and counterweight locations can be established to guide users to quickly find the precise location range where the counterweight needs to be placed for a specific crankshaft type.

[0081] Figure 12 An exemplary user interface on the output device of an eccentricity calibration system according to an embodiment of the present invention is shown. That is, the eccentricity calibration system 10 may also include an output device that includes a user interface, allowing the user to easily perform tests by inputting the counterweight adjustment stroke, testing the maximum speed and the allowable deviation of the maximum speed torque, and intuitively obtain the test results from the user interface.

[0082] This arrangement allows for quick identification and adjustment of crankshaft eccentricity to improve work efficiency; it can be integrated into existing equipment structures, requiring minimal mechanical modification work, and is easy and quick to operate; it has low manufacturing costs and high accuracy; and it can be extended to other similar equipment to accurately identify eccentricity problems, thereby improving crankshaft machining accuracy, reducing mechanical wear, and extending equipment lifespan.

[0083] The above description is only a preferred embodiment of the present invention and is not intended to limit the invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An eccentric calibration system for a crankshaft grinding machine (100), the crankshaft grinding machine (100) comprising two supports (1) spaced apart from each other, each of the two supports (1) comprising a fixed support body (11) and a support rotating part (12) rotatably connected to the support body (11), the support rotating part (12) comprising a circular counterweight support turntable (121) and a crankshaft support turntable (122) spaced apart from each other and coaxially arranged, and a support shaft fixing the counterweight support turntable (121) and the crankshaft support turntable (122) together, the rotation axes (A) of the two support rotating parts (12) being coincident with each other, the crankshaft grinding machine (100) being configured in use such that a crankshaft (200) to be processed is fixed between the two crankshaft support turntables (122) of the two supports (1) to rotate together with the two support rotating parts (12). The crankshaft (200) is movable; each of the two supports (1) further includes a counterweight (13), the counterweight (13) being configured to be mounted to a counterweight guide rail (G) arranged diametrically on the counterweight support turntable (121) and fixed at any position on the counterweight guide rail (G), the two counterweight guide rails (G) being parallel to each other and each counterweight guide rail (G) including a first end (G1) and a second end (G2) opposite to each other, the first end (G1) and the second end (G2) being located on the circumference of the counterweight support turntable (121), in the initial position of mounting the crankshaft (200) the counterweight guide rail (G) being parallel to the vertical direction and the first end (G1) being located above the second end (G2), the projection point of the center of mass of the crankshaft (200) on the counterweight support turntable (121) being located on the counterweight guide rail (G), characterized in that, The eccentricity calibration system (10) includes: A sensing block (B) is disposed at the first end (G1) of the counterweight guide rail (G) of one of the two supports (1), and the one of the two supports (1) is driven by a motor. Four inductive switches are fixed on the main body (11) of the bracket and located in the same plane perpendicular to the rotation axis (A). This plane is parallel to the plane containing the counterweight support turntable (121) of the bracket. The four inductive switches are located on the circumference of a virtual circle (C1) centered on the rotation axis (A). A first virtual line connecting the first inductive switch (S1) and the third inductive switch (S3) is parallel to the vertical direction and passes through the center of the virtual circle (C1). The first inductive switch (S1) is located above the third inductive switch (S3). A second virtual line connecting the second inductive switch (S2) and the fourth inductive switch (S4) is perpendicular to the vertical direction and passes through the center of the virtual circle (C1). The processor is configured to: calculate the motor output torque measured when the sensing block (B) rotates through the four sensing switches with the counterweight (13) mounted at the center position of the counterweight guide (G), and adjust the position of the counterweight (13) on the counterweight guide (G) based on the measured motor output torque to compensate for the eccentricity of the crankshaft (200).

2. The eccentric calibration system for a crankshaft grinding machine according to claim 1, characterized in that, The processor is also configured to: A graph consisting of four curves representing the motor output torque versus rotational speed at the four inductive switches is obtained by gradually increasing the motor's speed; and The position of the counterweight (13) on the counterweight guide (G) is adjusted based on the obtained curve, and the curve of the counterweight (13) is calculated when it is installed in the current position until the four curves that are substantially overlapping are obtained in the curve.

3. The eccentric calibration system for a crankshaft grinding machine according to claim 2, characterized in that, The processor is configured to, in a curve calculated with the counterweight (13) installed at the center of the counterweight guide rail (G), if the motor output torques at the four inductive switches at the same rotational speed differ significantly and the motor output torque at the first inductive switch (S1) is the largest and the motor output torque at the third inductive switch (S3) is the smallest, then adjust the position of the counterweight (13) toward the second end (G2) of the counterweight guide rail (G).

4. The eccentric calibration system for a crankshaft grinding machine according to claim 2, characterized in that, The processor is configured to, in a curve calculated with the counterweight (13) installed at the center of the counterweight guide rail (G), if the motor output torques at the four inductive switches at the same rotational speed differ significantly and the motor output torque at the first inductive switch (S1) is the smallest and the motor output torque at the third inductive switch (S3) is the largest, then adjust the position of the counterweight (13) toward the first end (G1) of the counterweight guide rail (G).

5. The eccentric calibration system for a crankshaft grinding machine according to claim 2, characterized in that, The processor is configured to increase the rotational speed in increments of 100 RPM from 0 when calculating the curves of the counterweight (13) in various positions, until the maximum design speed of the motor is reached.

6. The eccentric calibration system for a crankshaft grinding machine according to claim 5, characterized in that, The processor is configured to rotate the support rotating part (12) of the support (1) at least 10 revolutions after each increase in rotation speed to reach a stable speed.

7. The eccentric calibration system for a crankshaft grinding machine according to claim 2, characterized in that, The processor is configured to select 2n+1 special positions on the counterweight guide rail (G) to divide the counterweight guide rail (G) into 2n equal-length position intervals, where n is a positive integer.

8. The eccentric calibration system for a crankshaft grinding machine according to claim 7, characterized in that, The processor is configured to: after determining a graph of the four curves that are substantially coincident for the crankshaft, store the location range of the counterweight to establish a database about the crankshaft type and the location of the counterweight.

9. The eccentric calibration system for a crankshaft grinding machine according to claim 1, characterized in that, The processor is also configured to: The motor output torque measured at the four inductive switches at the same rotational speed is added to a Cartesian coordinate system with the center of the virtual circle (C1) as the origin and the first and second virtual connecting lines as coordinate axes to simulate a virtual torque circle (C2), thereby obtaining a torque distribution roundness diagram; and The position of the counterweight (13) is adjusted toward the first end (G1) or the second end (G2) of the counterweight guide rail (G) based on the roundness of the torque virtual circle (C2) and the degree of deviation of the center of the torque virtual circle (C2) relative to the origin.

10. The eccentric calibration system for a crankshaft grinding machine according to claim 9, characterized in that, The torque distribution roundness diagram includes multiple virtual torque circles (C2) simulated at multiple different speeds.

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