CN110207981A - A kind of lossless ball screw assembly, Static stiffness measuring device - Google Patents

Abstract

The invention discloses a non-destructive ball screw pair static stiffness measuring device, which includes a test bench body, a loaded ball screw pair, a loaded beam, a pressure sensor, a pressurizing device, an axial displacement measuring device, a measuring disc, and a rotation measuring device , a rotating measurement reference component, a first guide rail, a ball screw pair to be tested, a torque transmission device, a torque sensor, a servo motor, a reducer, a synchronous pulley and an industrial computer. The industrial computer controls the servo motor to drive the reducer, the synchronous pulley and the loading ball screw pair to realize the loading of the loading beam. The pressure sensor reads the force of the screw to be tested in real time, and the axial displacement measuring device reads the change of its axial length in real time, and the axial static stiffness of the screw to be tested is obtained by dividing the two. The rotation measuring device compensates the experimental error caused by the rotation and torsion of the lead screw; the torque sensor reads the torque on the lead screw in real time, and then calculates the torsional static stiffness of the lead screw. The invention has the advantages of simple structure, easy operation and high reliability and accuracy of measurement results.

Description

A non-destructive ball screw pair static stiffness measurement device

technical field

The invention belongs to the field of rigidity detection of a ball screw pair, in particular to a non-destructive ball screw pair static stiffness measurement device.

Background technique

Ball screw pairs are widely used in feed systems. With the continuous increase of the speed of the ball screw pair, its vibration problem is becoming more and more prominent, which seriously affects the positioning accuracy and accuracy maintenance ability of the feed system. The rigidity of the ball screw pair seriously affects the transmission performance and vibration amplitude of the feed system. Insufficient rigidity of the ball screw pair has become the main obstacle for the development of CNC machine tools and automation equipment to high speed and high precision.

At present, there are some shortcomings in the measurement of the static stiffness of the ball screw pair. Many existing test equipment also need to cut off the sample when carrying out the rigidity test, which cannot meet the requirements of the non-destructive rigidity test. For example, the paper "Theoretical analysis of the static stiffness of the ball screw pair In "Development and Research on Test Platform", a vertical ball screw counter axial static stiffness measurement device is proposed, which can realize effective measurement of static stiffness measurement, but due to the limitation of experimental space, it is necessary Cutting off is a lossy way of measuring. In addition, most of the existing test equipment focuses on the axial static stiffness of the screw, without considering the influence of the torsional stiffness of the screw pair, and the measurement results have a certain deviation from the actual value.

Contents of the invention

The purpose of the present invention is to provide a measuring device capable of nondestructively measuring the static stiffness of a ball screw pair.

The technical solution to realize the purpose of the present invention is: a non-destructive ball screw pair static stiffness measurement device, including a test bench body, a loading ball screw pair, a loading beam, a pressure sensor, a pressurizing device, an axial displacement measuring device, Measuring disc, rotating measuring device, rotating measuring reference part, first guide rail, ball screw pair to be tested, torque transmission device, torque sensor, servo motor, reducer, synchronous pulley and industrial computer;

The test bench body includes a first base plate, a second base plate and a fixed beam, the first base plate is perpendicular to the second base plate, the fixed beam is arranged on the second base plate; the first base plate is arranged parallel to the second base plate and loaded through The first guide column of the beam, the end of the first guide column is fixedly connected to the fixed beam, the loading beam can slide on the first guide column; a pair of loaded ball screw pairs are symmetrically distributed along the axis of the second bottom plate, one end of which is connected to the The synchronous pulley is connected, and the other end runs through the loading beam and is fixed by the nut flange; the loading beam is equipped with a pressure sensor, a pressurizing device, and a ball screw pair to be tested in sequence along the symmetrical axis of a pair of loaded ball screw pairs. The ball screw pair penetrates the fixed beam and is fixed by the first nut tooling, the first nut tooling is provided with a measuring plate, and the axial displacement measuring device set on the ball screw pair to be tested is set between the measuring plate and the pressurizing device; The first guide rail is set on the second bottom plate, the torque sensor is fixed on the first slider and can slide along the first guide rail, and the torque transmission device is arranged on the torque sensor; the tail end of the ball screw pair to be tested is connected with the torque transmission device; the axial displacement Between the measuring device and the torque transmission device, there are N rotating measuring devices set on the ball screw pair to be tested. The rotating measuring device includes a displacement sensor and a supporting device for the displacement sensor. The displacement sensor and the rotating measuring reference part arranged on the second bottom plate Phase contact; servo motor, reducer, synchronous pulley and industrial computer are set on the test bench body, the industrial computer controls the servo motor to work and collects the data of the pressure sensor, displacement sensor and torque sensor at the same time, the servo motor is connected to the reducer, and the reducer Connected to the timing pulley.

Compared with the prior art, the present invention has the following significant advantages: 1) It is not necessary to cut off the sample when carrying out the rigidity test, which can meet the requirements of the non-destructive rigidity test; 2) The device is simple and convenient to operate, and the obtained data is true, reliable and repeatable 3) The error compensation of the measurement results can be performed through the rotating measuring device to make the measurement results more accurate; 4) The test bench has more comprehensive functions, and the torsional static stiffness of the screw can be further measured in combination with the torque sensor readings.

The present invention will be described in further detail below in conjunction with the accompanying drawings.

Description of drawings

Fig. 1 is an assembly diagram of the overall structure of the non-destructive ball screw pair static stiffness measuring device of the present invention.

Fig. 2 is a schematic diagram of the test bench body of the present invention.

Fig. 3 is a structural schematic diagram of the tooling auxiliary device of the present invention.

Fig. 4 is a schematic diagram of the structure of the first nut tooling of the present invention.

Fig. 5 is a structural schematic diagram of the pressurizing device of the present invention.

Fig. 6 is a schematic structural diagram of the rotation measuring device of the present invention.

Fig. 7 is a schematic structural diagram of the fixing device of the present invention.

Fig. 8 is a schematic structural diagram of the sensor fixture of the present invention.

Fig. 9 is a schematic diagram of the rotating measurement reference component of the present invention.

Fig. 10 is a schematic diagram of the structure of the adjustable V-shaped block of the present invention.

Fig. 11 is a schematic diagram of the torque transmission device of the present invention.

Detailed ways

In conjunction with Fig. 1, a non-destructive ball screw pair static stiffness measuring device of the present invention includes a test bench body 1, a loading ball screw pair 2, a loading beam 5, a pressure sensor 6, a pressurizing device 8, and an axial displacement measuring device 9. Measuring disc 10, rotating measuring device 12, rotating measuring reference part 13, first guide rail 15, ball screw pair to be measured 18, torque transmission device 19, torque sensor 20, servo motor 21, reducer 22, synchronous pulley 23 and industrial computer 24;

2, the test bench body 1 includes a first base plate 1-1, a second base plate 1-2 and a fixed beam 1-3, the first base plate 1-1 is perpendicular to the second base plate 1-2, and the fixed beam 1- 3 is arranged on the second base plate 1-2; the first guide column 3 parallel to the second base plate 1-2 and passing through the loading beam 5 is arranged on the first base plate 1-1, and the end of the first guide column 3 is fixedly connected to the fixed The beam 1-3, the loading beam 5 can slide on the first guide column 3; a pair of loading ball screw pairs 2 are symmetrically distributed along the axial direction of the second bottom plate 1-2, one end of which is connected with the synchronous pulley 23, and the other end They all run through the loading beam 5 and are fixed by the nut flange 4; the loading beam 5 is provided with a pressure sensor 6, a pressurizing device 8, and a ball screw pair 18 to be tested along the symmetrical axis of a pair of loading ball screw pairs 2 in sequence. The ball screw pair 18 runs through the fixed beam 1-3 and is fixed by the first nut tooling 11. The first nut tooling 11 is provided with a measuring disc 10, and the ball screw pair to be tested is set between the measuring disc 10 and the pressurizing device 8. Axial displacement measuring device 9 on 18; the first guide rail 15 is set on the second bottom plate 1-2, the torque sensor 20 is fixed on the first slide block 16-1 and can slide along the first guide rail 15, and the torque sensor 20 is provided with a torque Transmission device 19; the tail end of the ball screw pair 18 to be tested is connected to the torque transmission device 19; N rotation measuring devices set between the axial displacement measurement device 9 and the torque transmission device 19 are set on the ball screw pair 18 to be tested 12. The rotation measurement device 12 includes a displacement sensor 37 and a displacement sensor support device, the displacement sensor 37 is in contact with the rotation measurement reference part 13 arranged on the second bottom plate 1-2; Device 22, synchronous pulley 23 and industrial computer 24, industrial computer 24 controls servo motor 21 to work and collects the data of pressure sensor 6, displacement sensor 37 and torque sensor 20 simultaneously, servo motor 21 links to each other with reducer 22, reducer 22 and synchronous Belt pulley 23 links to each other.

Further, with reference to FIG. 3 , the static stiffness measuring device of the present invention also includes a tooling auxiliary device 7 for loading and unloading the first nut tooling 11, which is arranged on the second slider 16-2 of the first guide rail 15;

The tooling auxiliary device 7 includes a rotating plate 29, a support shaft 30, a support rod 31, a first base 32, and a baffle plate 33; Plate 33, the two ends of baffle plate 33 are all connected to rotatable rotating plate 29, and the two ends of first base 32 are all vertically arranged to be used for supporting the support bar 31 of rotating plate 29, and rotating plate 29 is provided with for bearing the first nut The support shaft 30 of the tooling 11.

Exemplarily preferably, with reference to FIG. 4 , the first nut tooling 11 is divided into left and right parts, on which taper holes 35 matching with corresponding support shafts 30 are evenly distributed.

Further, referring to FIG. 5 , the pressurizing device 8 includes an upper pressure plate 25 , a steel ball 27 , and a lower pressure plate 28 arranged sequentially from top to bottom. The upper pressure plate 25 is fixedly connected to the pressure sensor 6 , and the lower pressure plate 28 In contact with the ball screw pair 18 to be tested, the upper pressure plate 25 and the lower pressure plate 28 are connected through a connecting rod 26, and a steel ball 27 for transmitting axial load is arranged between the two pressure plates.

Further preferably, with reference to FIG. 6 , the displacement sensor supporting device in the rotation measuring device 12 includes a displacement sensor clamp 38, a clamp cover 39, and a fixing device 40, and the fixing device 40 is sleeved on the ball screw pair 18 under test, and the fixing device 40 is fixed Connect the clamp cover 39, the displacement sensor clamp 38 is fixedly connected on the clamp cover 39, and the displacement sensor 37 is fixed in the sensor clamp 38.

Exemplarily preferably, with reference to FIG. 7, the fixing device 40 includes a first threaded sleeve 41, an outer elastic taper sleeve 42, an inner elastic taper sleeve 43, and a housing 44. The first threaded sleeve 41, the outer elastic taper sleeve 42, the inner elastic taper sleeve The taper sleeves 43 are all located in the housing 44, wherein the inner elastic taper sleeve 43 is set on the ball screw pair 18 to be tested, the outer wall surface of the inner elastic taper sleeve 43 is a cone surface, and the outer wall surface of the inner elastic taper sleeve 43 is in contact with the outer elastic cone. The inner wall surface of the sleeve 42 is matched, the first threaded sleeve 41 is located above the outer elastic taper sleeve 42, and the outer elastic taper sleeve 42 and the inner elastic taper sleeve 43 are pressed together by cooperating with the inner thread of the shell 44, so that the rotating measuring device 12 is fixed on the ball screw pair 18 to be tested.

Exemplary preferably, with reference to Fig. 8, the sensor clamp 38 includes a clamp housing 45, a second threaded sleeve 46, a screw rod 47 and a nylon plug 48, the clamp housing 45 is fixed on the clamp sleeve 39, and the clamp housing 45 is equipped with a second Threaded sleeve 46, screw rod 47 and nylon plug 48, described nylon plug 48 one end has internal thread, and the other end is provided with the semicircle groove that is used for fixing displacement sensor 37, and wherein internal thread matches with the external thread of screw rod 47, the second threaded sleeve 46 is sleeved on the screw rod 47 and is connected with the inner thread of the fixture housing 45, and a compression spring is also set on the screw rod 47 between the second threaded sleeve 46 and the nylon plug 48, and the nylon plug 48 and the sensor are pressed tightly by adjusting the threaded sleeve 46 .

Further preferably, with reference to FIG. 9 , the rotating measurement reference part 13 includes a stainless steel plate 49, an aluminum frame 50, and a magnetic table base 51. One end of the aluminum frame 50 is fixedly connected to the stainless steel plate 49, and the other end is fixedly connected to the second bottom plate 1-2. On the magnetic base 51, the displacement sensor 37 is in contact with the stainless steel plate 49.

Further, referring to FIG. 10 , the static stiffness measuring device of the present invention also includes an adjustable v-shaped block 14, which is arranged on the third slider 16-3 of the first guide rail 15;

The adjustable v-shaped block 14 includes a second base 52, a bottom plate 53, a second guide rail 54, a displacement device 56, a v-shaped block 57, a second guide column 58, a ball screw pair 59, a bearing seat 61, and a deep groove ball bearing 62 , the bearing end cover 63, the handle 64, the second base 52 is arranged on the third slider 16-3 of the first guide rail 15, the second base 52 is fixedly connected to the base plate 53, and the second guide rail 54 is arranged on the base plate 53, The displacement device 56 is arranged on the slide block of the second guide rail 54, the second guide column 58 is arranged on the central axis of the base plate 53, the v-shaped block 57 contacting with the displacement device 56 is arranged on the second guide column 58, and the ball screw pair 59 is fixed on the displacement device 56 through the second nut tooling 60, and one end of the ball screw pair 59 matches the inner ring of the deep groove ball bearing 62 and has an interference fit with the handle 64, wherein the deep groove ball bearing 62 is arranged on the bottom plate 53 On the bearing housing 61.

Exemplarily preferably, with reference to FIG. 11 , the torque transmission device 19 includes a connecting piece 65 for connecting the torque transmission device 19 and the torque sensor 20 , and a flat key 66 for connecting the torque transmission device 19 and the ball screw pair 18 to be tested.

The non-destructive ball screw pair static stiffness measuring device of the present invention controls the servo motor to work through the industrial computer, drives the reducer, the synchronous pulley and the loading ball screw pair, and then realizes the loading of the loading beam. There is a pressure sensor on the loading beam, which can read the force of the screw to be tested in real time, and an axial displacement measuring device is also installed on the screw to be tested, which can read the change of the axial length of the screw to be tested in real time. The static stiffness of the ball screw counter to be tested can be obtained by dividing the two. In addition, there is a rotation measuring device on the lead screw to be tested, which can compensate the experimental error caused by the rotation and torsion of the lead screw; at the same time, the torque sensor is fixedly connected to the tail of the lead screw through a torque transmission device, which can read the position of the lead screw in real time. By the torque, and then calculate the screw torsional static stiffness. The invention can not only realize the non-destructive measurement of the static stiffness of the ball screw pair, but also is easy to operate, has high reliability, high repeatability of experimental data, true and reliable measurement data, and high accuracy of measurement results.

Claims (10)

1. a kind of lossless ball screw assembly, Static stiffness measuring device, which is characterized in that including testing stand stage body (1), loaded ball Lead screw pair (2), load crossbeam (5), pressure sensor (6), pressurizing device (8), axial shift measuring instrument (9), Measuring plate (10), rotary measurement device (12), wheel measuring reference component (13), the first guide rail (15), ball screw assembly, to be measured (18), torsion Square transfer device (19), torque sensor (20), servo motor (21), retarder (22), synchronous pulley (23) and industrial personal computer (24)；

The testing stand stage body (1) includes the first bottom plate (1-1), the second bottom plate (1-2) and fixed cross beam (1-3), the first bottom plate (1-1) and the second bottom plate (1-2) is perpendicular, and fixed cross beam (1-3) is set on the second bottom plate (1-2)；On first bottom plate (1-1) First guide post (3) parallel with the second bottom plate (1-2) and through load crossbeam (5) is set, and the end of the first guide post (3) is solid It is connected in fixed cross beam (1-3), load crossbeam (5) can be slided on the first guide post (3)；A pair of of loaded ball lead screw pair (2) edge The axially symmetric distribution of second bottom plate (1-2), one end are connected with synchronous pulley (23), and the other end runs through load crossbeam (5) And it is fixed by nut flange (4)；Symmetry axis in load crossbeam (5) along a pair of of loaded ball lead screw pair (2) sets gradually pressure Force snesor (6), pressurizing device (8), ball screw assembly, to be measured (18), ball screw assembly, (18) to be measured run through fixed cross beam (1- 3) and it is fixed by the first nut tooling (11), Measuring plate (10) are set in the first nut tooling (11), Measuring plate (10) with plus The axial shift measuring instrument (9) being placed on ball screw assembly, to be measured (18) is set between pressure device (8)；Second bottom plate (1-2) The first guide rail of upper setting (15), torque sensor (20), which is fixed on the first sliding block (16-1), to be slided along the first guide rail (15), Torque transmitter (19) are set on torque sensor (20)；The tail end and torque transmitter of ball screw assembly, (18) to be measured (19) it is connected；It is arranged between axial shift measuring instrument (9) and torque transmitter (19) and N number of is placed on ball screw assembly, to be measured (18) rotary measurement device (12), rotary measurement device (12) include displacement sensor (37) and displacement sensor support dress It sets, displacement sensor (37) is in contact with the wheel measuring reference component (13) being arranged on the second bottom plate (1-2)；Testing stand platform Servo motor (21), retarder (22), synchronous pulley (23) and industrial personal computer (24) are set on body (1), and industrial personal computer (24) control is watched It takes motor (21) work while acquiring the data of pressure sensor (6), displacement sensor (37) and torque sensor (20), servo Motor (21) is connected with retarder (22), and retarder (22) is connected with synchronous pulley (23).

2. lossless ball screw assembly, Static stiffness measuring device according to claim 1, which is characterized in that the Static stiffness is surveyed Amount device further includes the tooling auxiliary device (7) for loading and unloading the first nut tooling (11), is arranged in the first guide rail (15) On second sliding block (16-2)；

The tooling auxiliary device (7) includes rotating plate (29), support shaft (30), support rod (31), first base (32), baffle (33)；The first base (32) and the second sliding block (16-2) are connected, and baffle (33) are arranged in first base (32), baffle (33) Both ends be all connected with rotatable rotating plate (29), the both ends of first base (32) are vertically arranged the branch for being used to support rotating plate (29) Strut (31), setting is for carrying the support shaft (30) of the first nut tooling (11) on rotating plate (29).

3. lossless ball screw assembly, Static stiffness measuring device according to claim 1 or 2, which is characterized in that described first Nut tooling (11) is divided into two pieces of left and right, is evenly equipped with the taper hole (35) with respective support axis (30) cooperation thereon.

4. lossless ball screw assembly, Static stiffness measuring device according to claim 3, which is characterized in that the pressurizing device It (8) include the upper platen (25), steel ball (27), pressing disc (28) set gradually from top to bottom, the upper platen (25) and pressure Sensor (6) is connected, and pressing disc (28) is in contact with ball screw assembly, to be measured (18), and upper platen (25) and pressing disc (28) pass through Connecting rod (26) is connected, and the steel ball (27) for transmitting axial load is arranged between two platens.

5. lossless ball screw assembly, Static stiffness measuring device according to claim 4, which is characterized in that the displacement sensing Device support device includes displacement sensor fixture (38), fixture set (39), fixed device (40), and fixed device (40) are placed on tested Ball screw assembly, (18) is connected fixture set (39) on fixed device (40), and be connected displacement sensor fixture on fixture set (39) (38), displacement sensor (37) is fixed in clamp of sensor (38).

6. lossless ball screw assembly, Static stiffness measuring device according to claim 5, which is characterized in that the fixed device It (40) include the first thread bush (41), outer elastic conical drogue (42), interior elastic conical drogue (43), shell (44), first thread bush (41), outer elastic conical drogue (42), interior elastic conical drogue (43) are respectively positioned in shell (44), wherein interior elastic conical drogue (43) is covered to be measured On ball screw assembly, (18), the outside wall surface of interior elastic conical drogue (43) is the conical surface, the outside wall surface and outer elasticity of interior elastic conical drogue (43) The inner wall of tapered sleeve (42) matches, and the first thread bush (41) is located at the top of outer elastic conical drogue (42), by with shell (44) Internal screw thread match and compress outer elastic conical drogue (42) and interior elastic conical drogue (43), to keep rotary measurement device (12) fixed On ball screw assembly, to be measured (18).

7. lossless ball screw assembly, Static stiffness measuring device according to claim 5 or 6, which is characterized in that the sensing Device fixture (38) includes fixture shell (45), the second thread bush (46), screw rod (47) and nylon plug (48), the fixture shell (45) it is fixed on fixture set (39), equipped with the second thread bush (46), screw rod (47) and nylon plug inside fixture shell (45) (48), there is internal screw thread in described nylon plug (48) one end, and the other end is equipped with the half slot for fixed displacement sensor (37), wherein Internal screw thread is matched with the external screw thread of screw rod (47), the second thread bush (46) cover on screw rod (47) and with fixture shell (45) Internal screw thread connects, and also sets up pressure spring on the screw rod (47) between the second thread bush (46) and nylon plug (48), passes through adjusting Thread bush (46) compresses nylon plug (48) and sensor.

8. lossless ball screw assembly, Static stiffness measuring device according to claim 7, which is characterized in that the wheel measuring Reference component (13) includes stainless steel plate (49), aluminum frame (50), Magnetic gauge stand (51), the connected stainless steel plate in one end of aluminum frame (50) (49), the connected Magnetic gauge stand (51) being set on the second bottom plate (1-2) of the other end, displacement sensor (37) and stainless steel plate (49) it is in contact.

9. lossless ball screw assembly, Static stiffness measuring device according to claim 8, which is characterized in that the Static stiffness is surveyed Measuring device further includes adjustable V-shaped block (14), is arranged on the third sliding block (16-3) of the first guide rail (15)；

The adjustable V-shaped block (14) includes second base (52), bottom plate (53), the second guide rail (54), gearshift (56), V-shaped Block (57), the second guide post (58), ball screw assembly, (59), bearing block (61), deep groove ball bearing (62), bearing (ball) cover (63), Handle (64), the second base (52) is arranged on the third sliding block (16-3) of the first guide rail (15), in second base (52) It is connected bottom plate (53), is arranged the second guide rail (54) on bottom plate (53), the sliding block in the second guide rail (54) is arranged in gearshift (56) On, it is arranged on the central axis of bottom plate (53) the second guide post (58), setting and gearshift (56) phase in the second guide post (58) The V-shaped block (57) of contact, ball screw assembly, (59) are fixed on gearshift (56) by the second nut tooling (60), ball wire One end of thick stick pair (59) merges with the matching of deep groove ball bearing (62) inner ring to be interference fitted with handle (64), wherein deep groove ball bearing (62) it is arranged on the bearing block (61) for being fixed on bottom plate (53).

10. lossless ball screw assembly, Static stiffness measuring device according to claim 9, which is characterized in that the torque passes Delivery device (19) includes the connector (65) for connecting torque transmitter (19) and torque sensor (20), is turned round for connecting The flat key (66) of square transfer device (19) and ball screw assembly, to be measured (18).