A cylindrical intermittent cam profile error and dynamics detection system and method

Abstract

The present invention belongs to the technical field of cam detection, and discloses a cylindrical intermittent cam profile error and cam dynamics detection system and method. The device on the experimental table is connected to the measurement and control device through a cable; the first base is fixed with a column by bolts, the upper end of the column is provided with a height adjustment handwheel, and a lead screw is installed in the middle of the column; the cross arm is fixed to the lead screw on the nut seat; the upper end of the cross arm is fixed with a fixed cover by bolts, and the upper end of the fixed cover is fixed with a torque sensor and a dividing plate encoder by bolts; the lower end of the cross arm is provided with a second three-jaw chuck, the upper end of the second three-jaw chuck is fixed with an acceleration sensor by bolts, and the second three-jaw chuck is clamped with the dividing plate; the first base is installed with a lead screw, and a support frame is fixed on the lead screw nut seat of the base, and the support frame is fixed with a rotating shaft through a bearing, and the rotating shaft is fixed with a cylindrical intermittent cam, a first three-jaw chuck and a gear through a connecting key. The present invention eliminates the principle error of detection.

Description

Technical Field

[0001] The invention belongs to the technical field of cam detection, and in particular relates to a cylindrical intermittent cam profile surface error and dynamics detection system and method. Background Art

[0002] At present, the cylindrical intermittent cam mechanism can convert continuous rotation input into intermittent motion output. It is widely used in automated production lines such as food processing, beverage filling and packaging industries involving multi-station work due to its large number of divisions, the rest time and movement time of the motion curve can be changed according to needs, the positioning segment has high accuracy and low vibration.

[0003] The machining accuracy of the cam determines the running speed and noise of the cylindrical intermittent cam mechanism. Since the profile of the cylindrical intermittent cam is a non-developable surface, machining and inspection are very difficult. Some companies use long-term running instead of further finishing and inspection after machining. There are also three-coordinate measuring machines to detect the coordinates of surface points. Due to the diameter of the measuring ball, it is also necessary to calculate the actual surface coordinate points based on the surface curvature and the measuring ball diameter. Since the curvature of each point on the cylindrical intermittent cam surface is different, the estimated curvature causes a large surface fitting error. Then the fitted surface point coordinate data is compared with the theoretical coordinate points for positioning and calculation. The calculations are relatively complicated and are not suitable for on-site measurements and large-scale sample measurements. At the same time, they cannot measure the flexibility of the cam's curve. The cam's machining accuracy is measured by measuring the cam's motion accuracy, and the cam's machining error is indirectly measured by measuring the angular error of the indexing plate based on the meshing relationship between the indexing plate and the cam. If the indexing plate roller diameter used for detection is inconsistent with the actual indexing plate roller diameter that meshes with the cam, the contact line will be a spatial curve when the cam and roller mesh due to the non-developability of the cam profile. When the roller diameter changes, the contact angle changes, resulting in inconsistent contact points and measurement errors.

[0004] In summary, the problems existing in the prior art are: it is difficult to detect cylindrical intermittent cams, especially for large-scale cam accuracy detection at cam production sites; general three-coordinate detection requires long equipment adjustment time and slow detection speed; it is incapable of measuring the dynamic performance of the cam surface; there is a lack of special equipment that can detect both surface accuracy and surface dynamic performance, resulting in low processing accuracy of domestic cams, and only cams suitable for medium and low speed applications can be produced. Summary of the invention

[0005] In view of the problems existing in the prior art, the present invention provides a cylindrical intermittent cam profile surface error and dynamics detection system and method.

[0006] The present invention is implemented as follows: a method for detecting the profile error and dynamics of a cylindrical intermittent cam, the method comprising: setting the motor speed and the movement law of the cam by means of a measurement and control device, opening the second three-jaw chuck, clamping the dividing plate, and then aligning and clamping the dividing plate; opening the first three-jaw chuck to clamp the cam, and turning the top locking handwheel to provide auxiliary support for the top, aligning and clamping the cam; turning the first handwheel, moving the support frame, adjusting the center distance between the cam and the dividing plate to the designed center distance, turning the height adjustment handwheel to move the dividing plate up and down so that the cam and the dividing plate are meshed; and then using a feeler gauge to measure the gap between the dividing plate roller and the cam groove to detect whether the width of the cam groove is qualified.

[0007] Furthermore, the cylindrical intermittent cam profile surface error and dynamics detection method also includes: when manually measuring the cam profile surface error, allowing the electromagnetic clutch to disconnect the camshaft and the motor, rotating the cam to rotate the handwheel, driving the cam to move through the gear transmission, the camshaft drives the cam encoder to rotate through the gear connection, the cam and the dividing plate are meshed, driving the dividing plate to move, adjusting the torque adjustment bolt to load the dividing plate, rotating the handwheel to measure, and obtaining the angular relationship between the cam and the dividing plate by reading the data of the cam encoder and the dividing plate encoder, comparing with the design curve, obtaining the error and displaying it; automatic measurement, reducing the motor speed through the measurement and control device, using the motor to drive the cam to rotate, and completing the cam profile surface error measurement.

[0008] Furthermore, the cylindrical intermittent cam profile error and dynamics detection method further includes: when performing cam dynamics measurement, the motor speed is set by the measurement and control device, the electromagnetic clutch connects the camshaft and the motor, the motor is started, the indexing plate and the cam are engaged, the data of the cam encoder and the indexing plate encoder are read to obtain the rotation angle relationship between the cam and the indexing plate, the numerical value is differentiated to obtain the speed relationship, the speed is differentiated to obtain the acceleration signal, the vibration information of the indexing plate is obtained by reading the acceleration sensor, and the signal is displayed on a split screen;

[0009] The acceleration sensor is used for the acceleration and vibration measurement of the cam's dynamic detection. First, a low-pass filter is performed to filter out clutter, and then the signal is adopted. The acceleration value signal AXIAN is collected and converted into an angular acceleration of AJIAO=AXIAN / R, where R is the distance from the sensor to the center of rotation;

[0010] After obtaining the angular velocity and acceleration signals of the cam and indexing plate, the data is displayed. The horizontal axis is the cam rotation angle, and the vertical axis is the angle, angular velocity and angular acceleration signals of the indexing plate respectively.

[0011] The pulse encoder outputs two square wave signals of phase A and phase B. The counter is used to calculate the total number of pulses NUM. Phase A leads phase B by 90 degrees. In forward rotation, a pulse NUM is added by 1. Conversely, phase B leads phase A by 90 degrees. In reverse rotation, a pulse NUM is subtracted by 1. The number of encoder lines is N, and it is subdivided by 4 times. The total angle rotated is angle = 360 * NUM / N / 4, unit: degree; speed calculation, the number of pulses VNUM accumulated once per unit time t milliseconds, calculate the speed V = 1000 * 360 * VNUM / 4 / t, unit: degree / second; angular acceleration calculation A = 1000 * (V t -V t-1 ) / t,V t is the speed at time t, unit: degree 2 / Second;

[0012] Calculation of coordinate errors of each point on the cam profile of the cylindrical intermittent cam: Establish the coordinate system O1-X1Y1Z1 of the cylindrical intermittent cam mechanism, and use the meshing principle and space tensor transformation method to obtain the working profile equation of the cam in the O1-X1Y1Z1 coordinate system:

[0013]

[0014]

[0015] Where, l: distance from the centerline of the roller to the rotating axis, c: center distance, R: roller radius, δ: distance from any section of the roller to the camshaft, β: contact angle between the cam and the roller, τ, θ: rotation angles of the rocker and cam, respectively, and satisfy the motion law of the cam: τ = τ0 + τ(θ);

[0016] By measuring the known rotation angle error Δτ of the indexing plate, according to the working profile equation, the actual profile equation is:

[0017]

[0018]

[0019] According to the motion law of the cam τ=τ0+τ(θ) and different δ values, the error values ​​of each point on the working profile can be obtained:

[0020]

[0021] Another object of the present invention is to provide a cylindrical intermittent cam profile surface error and dynamics detection system for implementing the cylindrical intermittent cam profile surface error and dynamics detection method, wherein the cylindrical intermittent cam profile surface error and dynamics detection system is provided with:

[0022] Experimental bench and measurement and control equipment;

[0023] The torque sensor, indexing disc encoder, motor, acceleration sensor, and electromagnetic clutch on the experimental table are connected to the measurement and control device through cables;

[0024] The first base is fixed with a column by bolts, a hand wheel for adjusting the height of a horizontal arm is arranged at the upper end of the column, a lead screw is installed in the middle of the column; the horizontal arm is fixed on the lead screw on the nut seat;

[0025] A fixed cover is fixed to the upper end of the cross arm by bolts, and a torque sensor 1 and a dividing plate encoder are fixed to the upper end of the fixed cover by bolts;

[0026] A second three-jaw chuck is arranged at the lower end of the cross arm, an acceleration sensor is fixed to the upper end of the second three-jaw chuck by bolts, and the second three-jaw chuck is clamped with the indexing plate;

[0027] The upper end of the first base is fixed to the support frame on the screw nut seat by bolts, the support frame is fixed with a rotating shaft through a bearing, the rotating shaft is fixed with a cylindrical intermittent cam, a first three-jaw chuck and a gear through a connecting key, the gear is connected to the motor through a coupling, and the motor is fixed to the support frame by bolts;

[0028] A cam rotating hand wheel is arranged at the upper end of the motor, and the cam rotating hand wheel is connected to the gear through a connecting shaft, and the gears are meshed with each other;

[0029] A top tightening hand wheel is arranged at the left end of the supporting frame, and the top tightening hand wheel is connected with the rotating shaft through a coupling.

[0030] Furthermore, the column screw is provided with a housing, a shaft sleeve is embedded in the upper end of the housing, a third bearing is sleeved on the shaft sleeve, and a first bearing end cover is fixed to the upper end of the shaft sleeve by bolts;

[0031] A second bearing end cover is embedded at the lower end of the housing, a fourth bearing is embedded in the second bearing end cover, and the second bearing end cover is connected to the first end cover by bolts;

[0032] The third bearing and the fourth bearing are sleeved with a first lead screw, the first lead screw is over-fitted with the second hand wheel shaft hole, and are fixed together by locking bolts.

[0033] Further, the left end of the cross arm is fixed with a fixed end cover by bolts, the cross arm is embedded with a first bearing seat, the first bearing seat is sleeved with a first bearing, and the first bearing is sleeved with a rotating shaft; a transverse sliding groove is opened on the fixed end cover, a friction plate is clamped in the transverse sliding groove, a spring is placed in a blind hole on the friction plate, the other end of the spring is sleeved on a spring washer, the inner hole of the spring washer is sleeved with a torque adjustment screw, the torque adjustment bolt is adjusted, the spring is compressed or loosened through the spring washer, the spring pushes the friction plate to move in the groove, and the other side of the friction plate contacts the shaft surface;

[0034] The rotating shaft is connected to the second pulley through a connecting key, and the upper end of the rotating shaft is connected to the third coupling, and a torque sensor is arranged on the upper end of the third coupling; wherein the friction plate is in hard contact with the rotating shaft;

[0035] A shaft is fixed to the upper right end of the cross arm through a bearing, the upper end of the shaft is connected to the first pulley through a connecting key, the shaft is connected to the second coupling, and a dividing disk encoder is arranged on the upper end of the second coupling; wherein the first pulley and the second pulley are connected through a transmission belt.

[0036] Furthermore, a third bearing seat is arranged on the left end of the base, a fifth bearing is embedded in the third bearing seat, a second lead screw is sleeved on the fifth bearing, and a second end cover is arranged on the left side of the fifth bearing;

[0037] A second lead screw nut seat is provided on the second lead screw, a fourth bearing seat is clamped on the right end of the second base, the second lead screw is sleeved on the fourth bearing seat, a third end cover is fixed to the outer side of the fourth bearing seat by bolts, the second lead screw is over-fitted with the third handwheel shaft hole, and is fixed by a locking nut.

[0038] Furthermore, the test bench is provided with a first base, a 1mm scale is provided at the upper end of the first base, a 0.05mm scale is provided at the right end of the first base, and a locking nut is used to fix the first hand wheel and the lead screw at the right end of the first base.

[0039] Furthermore, a display screen is embedded on the measuring and controlling device, and a button is embedded on the right end of the display screen; a switch is arranged on the bottom side of the measuring and controlling device, and a heat dissipation window is arranged on the right side of the measuring and controlling device.

[0040] Another object of the present invention is to provide a cam mechanical detection system for implementing the cylindrical intermittent cam profile surface error and dynamics detection method.

[0041] In summary, the advantages and positive effects of the present invention are as follows: the present invention adopts the cylindrical intermittent cam and the real indexing plate to mesh, detects the cam surface error by measuring the rotation angle error of the indexing plate, and uses the profile equation of the cylindrical intermittent cam to calculate the coordinates of the real cam profile and the coordinate errors of the coordinate points, and uses the feeler gauge to measure the slot width error, and can also measure the dynamics of the cam. The equipment is fast to adjust and is suitable for on-site cylindrical intermittent cam detection. The support frame of the present invention is used to install and fix the cam rotation system, the motor is fixed on the support frame, connected with the camshaft through an electromagnetic clutch, the camshaft is installed with a transmission gear and connected with a cam encoder, connected with a gear and a handwheel, connected with the first three-jaw chuck through a coupling, the cam is fixed on the first three-jaw chuck, the other side of the cam is auxiliary supported by the top, the thread in the middle part of the top is connected with the thread of the fixed sleeve, the cylindrical indexing cam is tightened and loosened by the top locking handwheel, the top shaft and the handwheel hole are matched, and locked by a locking screw.

[0042] The present invention can realize the up and down movement of the cross arm by fixing the cross arm on the column screw. The indexing plate can be loaded during detection. The torque sensor is fixed on the fixed end cover, fixedly connected to the shaft through the coupling, fixed to the shaft and the pulley, and the load is transmitted to the indexing plate through the conveyor belt. The fixed end cover is provided with a transverse slide groove and a threaded hole, and the two friction plates can move along the groove. The torque adjustment bolt and the spring washer are sleeved, and the other end of the spring is in the blind hole of the friction plate. The torque adjustment bolt is rotated, and the spring is compressed or loosened through the spring washer. The spring pushes the friction plate to move in the groove. When tightened, the friction plate and the shaft are frictionally loaded; the shaft is supported by the bearing and the bearing seat.

[0043] The present invention can realize the movement of the support frame by arranging a screw and a hand wheel on the base; the base screw is rotated by shaking the hand wheel to drive the support frame to move on the base track; a scale is arranged on the first base to display the distance from the central axis of the cam to the central axis of the dividing plate, which is used to adjust the center distance during detection. The motion law and geometric parameters of the cam to be tested are designed by pressing keys, and the motor speed is set to control the separation and combination of the electromagnetic clutch, and the encoder signals of the camshaft encoder and the dividing plate shaft are read. The motion curve law of the cam is the motion relationship between the rotation angle of the camshaft and the rotation angle of the dividing plate. The rotation angle signal of the camshaft encoder is used as the horizontal coordinate, and the rotation angle signal of the dividing plate is used as the vertical coordinate to display the motion law of the rotation angle, and the error is calculated and displayed according to the designed motion law; at the same time, the time derivative of the dividing plate rotation angle signal and the time derivative of the camshaft dividing plate signal can be used to calculate the relationship between the speeds, read the acceleration sensor signal, and obtain the acceleration and vibration signal of the dividing plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 It is a schematic diagram of the structure of a cylindrical intermittent cam profile surface error and dynamics detection system provided by an embodiment of the present invention.

[0045] Figure 2 It is a schematic diagram of the structure of a test bench provided in an embodiment of the present invention.

[0046] Figure 3 It is a right schematic diagram of the experimental platform provided in an embodiment of the present invention.

[0047] Figure 4 It is a schematic diagram of the structure of the dividing plate fixing device provided in an embodiment of the present invention.

[0048] Figure 5 It is a schematic diagram of the column lead screw nut structure provided by an embodiment of the present invention.

[0049] Figure 6 It is a schematic diagram of the first loading structure provided by an embodiment of the present invention.

[0050] Figure 7It is a schematic diagram of a second loading structure provided by an embodiment of the present invention.

[0051] Figure 8 It is a schematic diagram of the base lead screw nut structure provided by an embodiment of the present invention.

[0052] Fig. 9 It is a schematic diagram of the structure of the measurement and control device provided in an embodiment of the present invention.

[0053] Fig.10 Schematic diagram of the curve relationship between the measured cam angle and the indexing plate angle, with the horizontal axis being the cam angle and the vertical axis being the indexing plate angle.

[0054] Fig.11 Schematic diagram of the curve relationship between the measured cam angle and the angular velocity of the indexing plate, with the horizontal axis being the cam angle and the vertical axis being the angular velocity.

[0055] Fig.12 Schematic diagram of the curve relationship between the measured cam angle and the indexing plate angular acceleration, with the horizontal axis being the cam angle and the vertical axis being the indexing plate angular acceleration.

[0056] Fig.13 Schematic diagram of the curve relationship between the measured cam angle and indexing angle error, with the horizontal axis being the cam angle and the vertical axis being the indexing plate angle error.

[0057] Fig.14 It is a schematic diagram of using a feeler gauge to detect the cam groove width provided by an embodiment of the present invention.

[0058] Fig.15 It is a schematic diagram of the coordinate system of the column intermittent cam mechanism provided in an embodiment of the present invention.

[0059] In the figure: 1. torque sensor; 2. indexing disk encoder; 3. cam rotation handwheel; 4. gear; 5. motor; 6. first three-jaw chuck; 7. support frame; 8. cylindrical intermittent cam; 9. first base; 10. 0.05mm scale; 11. first handwheel; 12. measurement and control device; 13. 1mm scale; 14. center tightening handwheel; 15. indexing disk; 16. second three-jaw chuck; 17. acceleration sensor; 18 , column; 19, cross arm; 20, torque adjustment screw; 21, fixed cover; 22, height adjustment hand wheel; 23, cam encoder; 24, electromagnetic clutch; 25, transmission gear; 26, first coupling; 27, top; 28, hand wheel shaft; 29, friction plate; 30, second coupling; 31, first pulley; 32, shaft; 33, transmission belt; 34, fixed end cover; 35, second pulley; 36, third coupling; 3 7. Torque sensor; 38. First bearing; 39. First bearing seat; 40. Bearing end cover; 41. Second bearing; 42. Second bearing seat; 43. Fourth coupling; 44. Transmission shaft; 45. Second hand wheel; 46. First bearing end cover; 47. Third bearing; 48. Bushing; 49. First lead screw; 50. First lead screw nut seat; 51. Second bearing end cover; 52. Fourth bearing; 53. First end cover; 54. Second end cover; 55. Fifth bearing; 56. Third bearing seat; 57. Second lead screw; 58. Second lead screw nut seat; 59. Fourth bearing seat; 60. Third end cover; 61. Third hand wheel; 62. Sixth bearing; 63. Second base; 64. Display screen; 65. Button; 66. Heat dissipation window; 67. Switch; 68. Locking screw; 69. Spring; 70. Spring washer; 71. Feeler gauge; 72. Roller; 73. Convex profile surface. DETAILED DESCRIPTION

[0060] In order to further understand the content, features and effects of the present invention, the following embodiments are given as examples and described in detail with reference to the accompanying drawings.

[0061] In view of the problems existing in the prior art, the present invention provides a cylindrical intermittent cam profile surface error and dynamics detection system and method, which will be described in detail below in conjunction with the accompanying drawings.

[0062] like Figure 1 As shown, the cylindrical intermittent cam profile surface error and dynamics detection system provided by the embodiment of the present invention includes: a test bench and a measurement and control device 12.

[0063] The torque sensor, indexing disc encoder, motor, acceleration sensor, and electromagnetic clutch on the experimental table are connected to the measurement and control device 12 through data cables.

[0064] like Figure 2-Figure 3As shown, the test bench provided by the embodiment of the present invention is provided with a first base 9, a 1 mm scale 13 is provided at the upper end of the first base 9, a 0.05 mm scale 10 is provided at the right end of the first base 9, and a first hand wheel 11 is fixed to the right end of the first base 9 through a bearing.

[0065] The first base 9 is fixed with a column 18 by bolts. A height adjustment hand wheel 22 is arranged on the upper end of the column 18. The column 18 is connected to a cross arm 19 through a lead screw.

[0066] A fixing cover 21 is fixed to the upper end of the cross arm 19 by means of bolts, and a torque sensor 1 and a dividing plate encoder 2 are fixed to the upper end of the fixing cover 21 by means of bolts.

[0067] A second three-jaw chuck 16 is provided at the lower end of the cross arm 19 , an acceleration sensor 17 is fixed to the upper end of the second three-jaw chuck 16 by bolts, and the second three-jaw chuck 16 is clamped with the indexing plate 15 .

[0068] A support frame 7 is fixed to the upper end of the first base 9 by bolts, a rotating shaft is fixed to the support frame 7 by a bearing, a cylindrical intermittent cam 8, a first three-jaw chuck 6 and a gear 4 are fixed to the rotating shaft by a connecting key, the gear 4 is connected to the motor 5 by a coupling, and the motor 5 is fixed to the support frame 7 by bolts.

[0069] A cam rotating hand wheel 3 is arranged at the upper end of the motor 5. The cam rotating hand wheel 3 is connected to the gear 4 through a connecting shaft, and the gears 4 are meshed with each other.

[0070] A top tightening hand wheel 14 is provided at the left end of the supporting frame 7, and the top tightening hand wheel 14 is connected to the rotating shaft through a coupling.

[0071] like Figure 4 As shown, the dividing plate fixing device provided in the embodiment of the present invention includes: a dividing plate encoder 2, a dividing plate 15, a second three-jaw chuck 16, a torque adjustment screw 69, a spring 70, a spring washer 20, a fixing cover 21, a friction plate 29, a second coupling 30, a first pulley 31, a shaft 32, a bearing end cover 40, a second bearing 41, a second bearing seat 42, and a fourth coupling 43.

[0072] The cross arm 19 is embedded with a second bearing seat 42, the second bearing seat 42 is sleeved with a second bearing 41, the upper end of the second bearing seat 42 is fixed with a bearing end cover 40 by bolts, the second bearing 41 is sleeved with a shaft 32, and the shaft 32 is connected to the first pulley 31 through a connecting key.

[0073] The upper end of the cross arm 19 is fixed with a fixed cover 21 by bolts, the upper end of the shaft 32 is connected to the indexing disk encoder 2 through the second coupling 30, and the indexing disk encoder 2 is fixed to the fixed cover 21 by bolts.

[0074] The fixed cover 21 is provided with a slide groove, in which a friction plate 29 is placed, and the friction plate 29 is in line contact with the shaft 32; a torque adjustment screw 20 is screwed onto the fixed cover 21, and the end of the torque adjustment screw 20 is sleeved with a spring washer 70, and a spring 69 is sleeved with the spring washer, and the other end of the spring is placed in the blind hole of the friction plate 29; the shaft 32 is connected to the second three-jaw chuck 16 through the fourth coupling 43, and the second three-jaw chuck 16 is clamped with the dividing plate 15.

[0075] like Figure 5 As shown, the column screw nut pair provided in the embodiment of the present invention includes: a second hand wheel 45, a first bearing end cover 46, a third bearing 47, a sleeve 48, a first screw 49, a first screw nut seat 50, a second bearing end cover 51, a fourth bearing 52 and a first end cover 53.

[0076] The column screw is provided with a housing, the upper end of which is embedded with a shaft sleeve 48 , the shaft sleeve 48 is sleeved with a third bearing 47 , and the upper end of the shaft sleeve 48 is fixed with a first bearing end cover 46 by bolts.

[0077] A second bearing end cover 51 is embedded in the lower end of the housing, a fourth bearing 52 is embedded in the second bearing end cover 51 , and the second bearing end cover 51 is connected to the first end cover 53 by bolts.

[0078] The third bearing 47 and the fourth bearing 52 are sleeved with a first lead screw 49 , and the first lead screw 49 is rotationally connected to the second hand wheel 45 .

[0079] Among them, the pitch of the first screw 49 is 5mm, the scale 10 is 100 grids, and the accuracy of each grid is 0.05mm.

[0080] like Figure 7 As shown, the loading structure provided by the embodiment of the present invention includes: a dividing plate encoder 2, a torque adjustment screw 20, a friction plate 29, a second coupling 30, a first pulley 31, a shaft 32, a transmission belt 33, a fixed end cover 34, a second pulley 35, a third coupling 36, a torque sensor 37, a first bearing 38, and a first bearing seat 39.

[0081] The left end of the cross arm 19 is fixed with a fixed end cover 34 by bolts, and the cross arm 19 is embedded with a first bearing seat 39, the first bearing seat 39 is sleeved with a first bearing 38, and the first bearing 38 is sleeved with a rotating shaft; a transverse slide groove is opened on the fixed end cover 34, and a friction plate 29 is clamped in the transverse slide groove, the end of the torque adjustment screw 20 is sleeved with a spring washer 70, the spring 69 is sleeved with the spring washer, and the other end of the spring is placed in the blind hole of the friction plate 29;.

[0082] The rotating shaft is connected to the second pulley 35 through a connecting key, and the upper end of the rotating shaft is connected to the third coupling 36. A torque sensor 37 is provided at the upper end of the third coupling 36. The friction plate 29 is in surface contact with the rotating shaft.

[0083] A shaft 32 is fixed to the upper right end of the cross arm 19 through a bearing, the upper end of the shaft 32 is connected to the first pulley 31 through a connecting key, the shaft 32 is connected to the second coupling 30, and a dividing plate encoder 2 is arranged on the upper end of the second coupling 30. The first pulley 31 and the second pulley 35 are connected by a transmission belt 33.

[0084] like Figure 8 As shown, the base screw nut pair provided by the embodiment of the present invention includes a second end cover 54, a fifth bearing 55, a third bearing seat 56, a second screw 57, a second screw nut seat 58, a fourth bearing seat 59, a third end cover 60, a third hand wheel 61, a sixth bearing 62, and a second base 63.

[0085] A third bearing seat 56 is disposed on the left end of the second base 63, a fifth bearing 55 is embedded in the third bearing seat 56, a second lead screw 57 is sleeved on the fifth bearing 55, and a second end cover 54 is disposed on the left side of the fifth bearing 55;

[0086] A second screw nut seat 58 is provided on the second screw 57, a fourth bearing seat 59 is clamped on the right end of the second base 63, the second screw 57 is sleeved on the fourth bearing seat 59, a third end cover 60 is fixed to the outer side of the fourth bearing seat 59 by bolts, and the second screw 57 is clamped with the third hand wheel 61.

[0087] like Fig. 9 As shown, the measurement and control device provided in the embodiment of the present invention includes: a display screen 64, a button 65, a heat dissipation window 66, and a switch 67.

[0088] A display screen 64 is embedded on the measuring and controlling device 12 , and a button 65 is embedded on the right end of the display screen 64 ; a switch 67 is provided on the bottom side of the measuring and controlling device 12 , and a heat dissipation window 66 is provided on the right side of the measuring and controlling device 12 .

[0089] The working principle of the present invention is as follows: the motor speed and the movement law of the cam are set by the measurement and control device, the second three-jaw chuck 16 is opened, the indexing plate 15 is clamped, and then the indexing plate 15 is aligned and tightened. The first three-jaw chuck 6 is opened to clamp the cam 8, and the top locking hand wheel 14 is turned to make the top 27 provide auxiliary support, and the cam 18 is aligned and clamped. The first rotating hand wheel 11 moves the support frame 7, adjusts the center distance between the cam and the indexing plate to the designed center distance, and the height adjustment hand wheel 22 is turned to move the up and down position of the indexing plate so that the cam and the indexing plate are meshed.

[0090] like Fig.14 As shown, a feeler gauge 71 is then used to measure the gap between the indexing plate roller 72 and the cam groove to detect whether the width of the cam groove is within the acceptable range.

[0091] When manually measuring the error of the cam profile surface 73, let the electromagnetic clutch 24 disconnect the connection between the camshaft and the motor, turn the cam to rotate the handwheel 3, and drive the cam to move through the gear 4. The cam and the indexing plate are meshed, driving the indexing plate to move, adjust the torque adjustment bolt 20 to tighten the spring 69, squeeze the friction plate 29 to tighten the shaft to load the indexing plate, turn the handwheel to measure, and obtain the angular relationship between the cam and the indexing plate by reading the data of the cam encoder and the indexing plate encoder, and compare it with the design curve to obtain the error and display it; for automatic measurement, reduce the motor speed through the measurement and control device, use the motor to drive the cam to rotate, and complete the cam profile surface 73 error measurement.

[0092] When measuring cam dynamics, the motor speed is set through the measurement and control device, the electromagnetic clutch connects the camshaft and the motor, the motor is started, the indexing plate and the cam are engaged, the data of the cam encoder and the indexing plate encoder are read to obtain the angular relationship between the cam and the indexing plate, the numerical value is differentiated to obtain the speed relationship, the acceleration and vibration information of the indexing plate is obtained by reading the acceleration sensor, and these signals are displayed on a split screen.

[0093] The measurement and control device consists of a control device, a display, and buttons. The buttons are used to design the motion law and geometric parameters of the cam to be measured; set the speed of the motor; control the separation and combination of the electromagnetic clutch; read the encoder signals of the camshaft encoder and the indexing plate shaft. The motion curve law of the cam is the motion relationship between the rotation angle of the cam shaft and the rotation angle of the indexing plate. The rotation angle signal of the camshaft encoder is used as the horizontal coordinate, and the rotation angle signal of the indexing plate is used as the vertical coordinate to display the motion law of the rotation angle. The error is calculated and displayed according to the designed motion law. At the same time, the relationship between the speeds can be calculated by taking the derivative of the indexing plate rotation angle signal with respect to time and the derivative of the camshaft indexing plate signal with respect to time, reading the acceleration sensor signal, and obtaining the acceleration and vibration signal of the indexing plate.

[0094] The pulse encoder outputs two square wave signals of phase A and phase B. The counter is used to calculate the total number of pulses NUM. Phase A leads phase B by 90 degrees. In forward rotation, a pulse NUM is added by 1. Conversely, phase B leads phase A by 90 degrees. In reverse rotation, a pulse NUM is subtracted by 1. The number of encoder lines is N, and it is subdivided by 4 times. The total angle rotated is angle = 360 * NUM / N / 4, unit: degree; speed calculation, the number of pulses VNUM accumulated once per unit time t milliseconds, calculate the speed V = 1000 * 360 * VNUM / 4 / t, unit: degree / second; angular acceleration calculation A = 1000 * (V t -V t-1 ) / t,V t is the speed at time t, unit: degree 2 / Second.

[0095] Signal processing of acceleration sensor. Acceleration sensor is mainly used for acceleration and vibration measurement of cam dynamic detection. First, low-pass filtering is performed to filter out noise, and then the signal is adopted. Kalman filtering is used. After the acceleration value signal AXIAN is collected, it is converted into angular acceleration AJIAO=AXIAN / R, where R is the distance from the sensor to the center of rotation.

[0096] After obtaining the angular velocity and acceleration signals of the cam and indexing plate, the data is displayed. The horizontal axis is the cam rotation angle, and the vertical axis is the angle, angular velocity and angular acceleration signals of the indexing plate respectively.

[0097] Calculation of coordinate errors of each point on the cam profile of the cylindrical intermittent cam: Establish the coordinate system O1-X1Y1Z1 of the cylindrical intermittent cam mechanism. Using the meshing principle and space tensor transformation method, the working profile equation of the cam in the O1-X1Y1Z1 coordinate system can be obtained:

[0098]

[0099]

[0100] In the formula, l: the distance from the center line of the roller to the rotating axis, c: the center distance, R: the roller radius, δ: the distance from any section of the roller to the camshaft, β: the contact angle between the cam and the roller, τ, θ: the rotation angles of the rocker and cam respectively, and satisfy the motion law of the cam: τ = τ0 + τ(θ).

[0101] Fig.14 The cylindrical intermittent cam mechanism coordinate system is measured by the known angular error of the indexing plate, that is, Δτ. According to the working profile equation, the actual profile equation can be obtained as follows:

[0102]

[0103]

[0104] According to the motion law of the cam τ=τ0+τ(θ) and different δ values, the error values ​​of each point on the working profile can be obtained:

[0105]

[0106] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any simple modification, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are within the scope of the technical solution of the present invention.

Claims

1. A cylindrical intermittent cam profile error and dynamics detection method, characterized in that: The cylindrical intermittent cam profile error and dynamics detection method comprises: setting the motor speed and the movement law of the cam by means of a measurement and control device, opening the second three-jaw chuck, clamping the indexing plate, and then aligning and clamping the indexing plate; opening the first three-jaw chuck to clamp the cam, and turning the top locking hand wheel to make the top perform auxiliary support, aligning and clamping the cam; turning the first hand wheel, moving the support frame, adjusting the center distance between the cam and the indexing plate to the designed center distance, turning the height adjustment hand wheel to move the upper and lower positions of the indexing plate so that the cam and the indexing plate are meshed; and then using a feeler gauge to measure the gap between the indexing plate roller and the cam groove to detect whether the width of the cam groove is qualified; The cylindrical intermittent cam profile error and dynamics detection method also includes: when manually measuring the cam profile error, allowing the electromagnetic clutch to disconnect the camshaft and the motor, rotating the cam to rotate the hand wheel, driving the cam to move through the gear transmission, the camshaft drives the cam encoder to rotate through the gear connection, the cam and the indexing plate are meshed, driving the indexing plate to move, adjusting the torque adjustment bolt to load the indexing plate, rotating the hand wheel to measure, and obtaining the rotation angle, rotation speed and acceleration relationship between the cam and the indexing plate by reading the data of the cam encoder and the indexing plate encoder, and comparing with the design curve, obtaining the error and displaying it; automatic measurement, reducing the motor speed through the measurement and control device, using the motor to drive the cam to rotate, and completing the cam profile error measurement; The cylindrical intermittent cam profile error and dynamics detection method further includes: when measuring cam dynamics, setting the motor speed through the measurement and control device, connecting the camshaft and the motor through the electromagnetic clutch, starting the motor, engaging the indexing plate and the cam, reading the data of the cam encoder and the indexing plate encoder to obtain the rotation angle relationship between the cam and the indexing plate, differentiating the value to obtain the speed relationship, differentiating the speed to obtain the acceleration signal, obtaining the vibration information of the indexing plate by reading the acceleration sensor, and displaying the signal on a split screen; The acceleration sensor is used for the acceleration and vibration measurement of the cam's dynamic detection. First, low-pass filtering is performed to filter out clutter, and then sampling is performed. The signal is filtered using Kalman filtering. After the acceleration value signal AXIAN is collected, it is converted into an angular acceleration of AJIAO=AXIAN / R, where R is the distance from the sensor to the center of rotation. After obtaining the angular velocity and acceleration signals of the cam and indexing plate, the data is displayed. The horizontal axis is the cam rotation angle, and the vertical axis is the angle, angular velocity and angular acceleration signals of the indexing plate respectively. The pulse encoder outputs two square wave signals of phase A and phase B. The counter is used to calculate the total number of pulses NUM. Phase A leads phase B, and when it rotates forward, a pulse NUM increases by 1. Conversely, phase B leads phase A, and when it rotates reversely, a pulse NUM decreases by 1. The number of encoder lines is N, and it is subdivided by 4 times. The total angle rotated is angle = 360 * NUM / N / 4, unit: degree; speed calculation, the number of pulses VNUM accumulated once per unit time t milliseconds, calculate the speed V = 1000 * 360 * VNUM / 4 / t, unit: degree / second; angular acceleration calculation A = 1000 * (V t -V t-1 ) / t, unit: degree 2 / sec, where V t is the speed at time t; Calculation of coordinate errors of each point on the cam profile of the cylindrical intermittent cam: Establish the coordinate system O1-X1Y1Z1 of the cylindrical intermittent cam mechanism, and use the meshing principle and space tensor transformation method to obtain the working profile equation of the cam in the O1-X1Y1Z1 coordinate system: Where, l: distance from the centerline of the roller to the rotating axis, c: center distance, R: roller radius, δ: distance from any section of the roller to the camshaft, β: contact angle between the cam and the roller, τ, θ: rotation angles of the rocker and cam, respectively, and satisfy the motion law of the cam: τ = τ0 + τ(θ); By measuring the known rotation angle error Δτ of the indexing plate, according to the working profile equation, the actual profile equation is: According to the motion law of the cam τ=τ0+τ(θ) and different δ values, the error values ​​of each point on the working profile can be obtained:

2. A cylindrical intermittent cam profile surface error and dynamics detection system for implementing the cylindrical intermittent cam profile surface error and dynamics detection method of claim 1, characterized in that: The cylindrical intermittent cam profile error and dynamics detection system is provided with: Experimental bench and measurement and control equipment; The torque sensor, indexing disc encoder, motor, acceleration sensor, and electromagnetic clutch on the experimental table are connected to the measurement and control device through cables; The first base is fixed with a column by bolts, a hand wheel for adjusting the height of a horizontal arm is arranged at the upper end of the column, a lead screw is installed in the middle of the column; the horizontal arm is fixed on the lead screw nut seat; A fixed cover is fixed to the upper end of the cross arm by bolts, and a torque sensor and a dividing plate encoder are fixed to the upper end of the fixed cover by bolts; A second three-jaw chuck is arranged at the lower end of the cross arm, an acceleration sensor is fixed to the upper end of the second three-jaw chuck by bolts, and the second three-jaw chuck is clamped with the indexing plate; The upper end of the first base is fixed to the support frame on the screw nut seat by bolts, the support frame is fixed with a rotating shaft by a bearing, the rotating shaft is fixed with a first three-jaw chuck and a gear by a connecting key, the gear is connected to the motor by a coupling, the motor is fixed to the support frame by bolts, and the cylindrical intermittent cam is installed on the first three-jaw chuck; A cam rotating hand wheel is arranged at the upper end of the motor, and the cam rotating hand wheel is connected to the gear through a connecting shaft, and the gears are meshed with each other; A top tightening hand wheel is arranged at the left end of the supporting frame, and the top tightening hand wheel is connected with the rotating shaft through a coupling.

3. The cylindrical intermittent cam profile error and dynamics detection system according to claim 2, characterized in that: The column screw is provided with a housing, a shaft sleeve is embedded in the upper end of the housing, the shaft sleeve is sleeved with a third bearing, and the upper end of the shaft sleeve is fixed with a first bearing end cover by bolts; A second bearing end cover is embedded at the lower end of the housing, a fourth bearing is embedded in the second bearing end cover, and the second bearing end cover is connected to the first end cover by bolts; The third bearing and the fourth bearing are sleeved with a first lead screw, the first lead screw is over-fitted with the second hand wheel shaft hole, and are fixed together by a locking bolt.

4. The cylindrical intermittent cam profile error and dynamics detection system according to claim 2, characterized in that: The left end of the cross arm is fixed with a fixed end cover by bolts, the cross arm is embedded with a first bearing seat, the first bearing seat is sleeved with a first bearing, and the first bearing is sleeved with a rotating shaft; a transverse sliding groove is opened on the fixed end cover, a friction plate is clamped in the transverse sliding groove, a spring is placed in a blind hole on the friction plate, the other end of the spring is sleeved on a spring washer, the inner hole of the spring washer is sleeved with a torque adjustment screw, the torque adjustment bolt is adjusted, the spring is compressed or loosened through the spring washer, the spring pushes the friction plate to move in the groove, and the other side of the friction plate contacts the shaft surface; The rotating shaft is connected to the second pulley through a connecting key, and the upper end of the rotating shaft is connected to the third coupling, and a torque sensor is arranged on the upper end of the third coupling; wherein the friction plate is in hard contact with the rotating shaft; A shaft is fixed to the upper right end of the cross arm through a bearing, the upper end of the shaft is connected to the first pulley through a connecting key, the shaft is connected to the second coupling, and a dividing disk encoder is arranged on the upper end of the second coupling; wherein the first pulley and the second pulley are connected through a transmission belt.

5. The cylindrical intermittent cam profile error and dynamics detection system according to claim 2, characterized in that: A third bearing seat is arranged on the left end of the base, a fifth bearing is embedded in the third bearing seat, a second lead screw is sleeved on the fifth bearing, and a second end cover is arranged on the left side of the fifth bearing; A second lead screw nut seat is provided on the second lead screw, a fourth bearing seat is clamped on the right end of the second base, the second lead screw is sleeved on the fourth bearing seat, a third end cover is fixed to the outer side of the fourth bearing seat by bolts, the second lead screw is over-fitted with the third handwheel shaft hole, and is fixed by a locking nut.

6. The cylindrical intermittent cam profile error and dynamics detection system according to claim 2, characterized in that: The experimental table is provided with a first base, a 1mm scale is provided on the upper end of the first base, a 0.05mm scale is provided on the right end of the first base, and a locking nut is used to fix the first hand wheel and the lead screw on the right end of the first base.

7. The cylindrical intermittent cam profile error and dynamics detection system according to claim 2, characterized in that: A display screen is embedded on the measuring and controlling device, and a button is embedded on the right end of the display screen; a switch is arranged on the bottom side of the measuring and controlling device, and a heat dissipation window is arranged on the right side of the measuring and controlling device.

8. A cam mechanical detection system for implementing the cylindrical intermittent cam profile error and dynamics detection method of claim 1.

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