Transmission mechanism applied to gantry three-coordinate measuring machine

Abstract

The invention discloses a transmission mechanism applied to a gantry three-coordinate measuring machine. The transmission mechanism comprises a main shoulder; the lead screw is arranged at the bottom of the main shoulder; the nut transmission mechanism comprises a nut and a nut sleeve which are arranged on the lead screw in a sleeving mode, and the nut is fixed in the nut sleeve; the speed reduction disc is fixedly arranged on the nut sleeve in a sleeving manner; the motor is mounted on the main shoulder and used for driving the speed reduction disc to rotate; the nut, the nut sleeve, the motor and the main shoulder are driven to linearly move along the lead screw through the rotation of the speed reducing disc; and the swing eliminating piece is used for slowing down swing of the lead screw. The nut serves as a main transmission mechanism and is connected with the speed reduction disc and the motor, the lead screw does not rotate any more, the lead screw can be stretched, the deflection of the lead screw is reduced, and therefore the precision of the measuring machine is greatly improved. Errors generated in actual assembly of the lead screw and deflection generated by stress of the lead screw can be eliminated through the swing eliminating piece, and transmission precision and stability are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of gantry three-coordinate measuring machines, and in particular to a transmission mechanism applied to a gantry three-coordinate measuring machine. Background Art

[0002] With the development of modern precision machining and manufacturing technology, more and more products have increasingly stringent requirements for measurement accuracy. Traditional measuring tools, such as tape measures, calipers, and micrometers, are no longer able to meet these requirements. To address the challenges of inspecting complex product geometries, coordinate measuring machines (CMMs) have emerged. Gantry-type CMMs are precision three-dimensional measuring instruments used primarily for inspecting component size, shape, and relative position.

[0003] With the widespread application of gantry-type three-dimensional coordinate measuring machines, the number of usage scenarios has gradually increased, and the current market requirements for large Y-axis travel are gradually increasing. In the application of long-stroke screw transmission, traditional screw transmission is that the screw rotates to drive the nut to move linearly along the axial direction of the screw. The screw is installed on the support seat, and the screw is connected to the motor using a coupling. During the installation process, the installation accuracy of the axial and radial runout of the screw is very high. The above has certain advantages for short-stroke screws, but for long-stroke screws exceeding 6m in length, the axial runout of the screw can still be solved, but the installation of radial runout is very difficult, and the long screw itself has a high deflection in the long direction, which greatly reduces the transmission accuracy of the nut. Summary of the Invention

[0004] The purpose of the present invention is to provide a transmission mechanism for a gantry coordinate measuring machine, wherein the swing eliminating member can eliminate the error generated by the lead screw during actual assembly and the deflection caused by the force on the lead screw, thereby improving the transmission accuracy and stability.

[0005] To this end, the present invention provides a transmission mechanism applied to a gantry three-coordinate measuring machine, comprising: a main shoulder; a lead screw, which is arranged at the bottom of the main shoulder; a nut transmission mechanism, comprising: a nut and a nut sleeve sleeve mounted on the lead screw, the nut being fixed in the nut sleeve; a reduction plate, fixedly mounted on the nut sleeve; a motor, mounted on the main shoulder and used to drive the reduction plate to rotate; the rotation of the reduction plate drives the nut, the nut sleeve, the motor and the main shoulder to move in a straight line along the lead screw; and a swing elimination member, used to slow down the swing of the lead screw.

[0006] Preferably, it further comprises a guide rail, the main shoulder is arranged above the guide rail, and an air bearing is provided at the bottom of the main shoulder.

[0007] Preferably, the lead screw is mounted on the guide rail via a lead screw mounting plate, and the lead screw extends along the direction of the guide rail.

[0008] Preferably, the nut transmission mechanism further comprises a bearing, the inner ring of the bearing is fixed on the nut sleeve, and the outer ring of the bearing is fixed with a nut connecting seat.

[0009] Preferably, the motor is mounted on a motor mounting plate, and the motor mounting plate is connected to the main shoulder.

[0010] Preferably, the swing elimination member includes an XY swing elimination member, which includes an XY swing block, and the XY swing block is connected to the nut transmission mechanism; the XY swing block is provided with an XY matching groove, and an XY bearing is provided in the XY matching groove, and the inner ring of the XY bearing is fixed with an XY swing axis.

[0011] Preferably, the swing elimination member includes a YZ swing elimination member, which includes a YZ swing block, and the YZ swing block is connected to the main shoulder; the YZ swing block is provided with a YZ matching groove, and a YZ bearing is provided in the YZ matching groove, and the inner ring of the YZ bearing is fixed with a YZ swing shaft.

[0012] Preferably, the XY swing axis and the YZ swing axis are perpendicular to each other, and both the XY swing axis and the YZ swing axis are perpendicular to the axial direction of the lead screw.

[0013] Preferably, the swing elimination member includes a mounting groove, which is connected to the main shoulder; the mounting groove includes a first mounting plate, and a second mounting plate and a third mounting plate are respectively vertically provided at both ends of the first mounting plate; the YZ swing block is installed between the second mounting plate and the third mounting plate, and the second mounting plate and the third mounting plate are provided with corresponding second mounting holes, and the two ends of the YZ swing axis are respectively fixed in the two second mounting holes.

[0014] Preferably, the YZ swing block is provided with two parallel and spaced-apart connecting plates, and the XY swing block is located between the two connecting plates; corresponding first mounting holes are provided on the two connecting plates, and the two ends of the XY swing axis are respectively fixed in the two first mounting holes.

[0015] Compared with the prior art, the advantages and positive effects of the present invention are: This application uses the nut as the main transmission mechanism, connected to the reduction plate and motor. The lead screw stops rotating, allowing it to be stretched, reducing its deflection and significantly improving the accuracy of the measuring machine. When the nut rotates, the lead screw remains stationary, and the nut only moves linearly. This reduces the friction and inertia generated by the lead screw's rotation, helping to improve transmission efficiency and ensure smoother transmission. When the nut rotates, the force applied to the lead screw becomes more even, reducing the possibility of localized wear, thereby improving transmission accuracy and stability.

[0016] The measuring machine of the present application includes a swing eliminating member, which can eliminate the error generated by the lead screw during actual assembly and the deflection caused by the force on the lead screw, thereby improving the transmission accuracy.

[0017] Other features and advantages of the present invention will become more apparent after reading the detailed description of the present invention in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is one of the structural schematic diagrams of an embodiment of the present invention applied to a transmission mechanism of a gantry coordinate measuring machine; Figure 2 This is a second structural diagram of an embodiment of the present invention applied to a transmission mechanism of a gantry coordinate measuring machine; Figure 3 This is a third structural diagram of an embodiment of the present invention applied to a transmission mechanism of a gantry coordinate measuring machine; Figure 4 It is a cross-sectional schematic diagram of an embodiment of the present invention applied to a transmission mechanism of a gantry coordinate measuring machine; Figure 5 This is a fourth structural diagram of an embodiment of the present invention applied to a transmission mechanism of a gantry coordinate measuring machine; Figure 6 This is a fifth structural diagram of an embodiment of the present invention applied to a transmission mechanism of a gantry coordinate measuring machine; Figure 7 This is one of the structural schematic diagrams of an embodiment of a swing elimination member of the present invention; Figure 8 This is a second structural diagram of an embodiment of a swing elimination member of the present invention; Figure 9 This is a schematic structural diagram of an embodiment of the YZ swing block of the present invention; Figure 10 This is a schematic structural diagram of an embodiment of an XY swing block of the present invention; Figure 11 This is a schematic structural diagram of an embodiment of the mounting slot of the present invention; Main shoulder 10, air bearing 11; Guide rail 20; Lead screw 30, lead screw mounting plate 31; Nut 40, nut sleeve 41, speed reducer 42, motor 43, belt 44, nut connection seat 45, bearing 46, motor mounting plate 47, stop sleeve 48; XY swing block 51, YZ swing block 52, XY swing axis 53, YZ swing axis 54, XY matching groove 55, YZ matching groove 56, connecting plate 57, first mounting hole 58; First mounting plate 61, second mounting plate 62, third mounting plate 63, second mounting hole 64, fourth mounting plate 65; A first shell plate 71 and a second shell plate 72 . DETAILED DESCRIPTION

[0019] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0020] like Figures 1-11 As shown, the present application provides a transmission mechanism applied to a gantry three-dimensional coordinate measuring machine, including: a main shoulder 10, a guide rail 20, a lead screw 30 and a nut transmission mechanism. The main shoulder 10 is arranged above the guide rail 20, the lead screw 30 is installed above the guide rail 20 and is located at the bottom of the main shoulder 10, and the nut transmission mechanism is installed on the main shoulder 10. The main shoulder 10 can be driven to move linearly along the lead screw 30 and the guide rail 20 through the nut transmission mechanism.

[0021] In one embodiment of the present application, an air bearing 11 is provided at the bottom of the main shoulder 10. By providing the air bearing 11, the main shoulder 10 can move smoothly in a straight line along the guide rail 20, thereby improving the accuracy and stability of the linear movement of the main shoulder 10.

[0022] The air bearing 11 may be a common air bearing in the technical field and is not specifically limited here.

[0023] In one embodiment of the present application, the lead screw 30 can be mounted on the guide rail 20 via a lead screw mounting plate 31, with the lead screw 30 extending axially in the direction of the guide rail 20. The lead screw mounting plate 31 is vertically fixed to the guide rail 20, and the fixing method can be a commonly used fixing installation method in the technical field, which is not specifically limited here. The lead screw mounting plate 31 is provided with a through hole for mounting the lead screw 30, and the lead screw 30 is fixed in the through hole. A gap is formed between the lead screw 30 and the top surface of the guide rail 20, and the lead screw 30 extends axially in the direction of the guide rail 20. The main shoulder 10 and the nut transmission mechanism can move linearly along the lead screw 30 and the guide rail 20.

[0024] The screw 30 is located at the bottom of the main shoulder 10. A groove (not shown in the figure) is provided at the bottom of the main shoulder 10. The groove can avoid the screw 30 and the screw mounting plate 31 to prevent the screw 30 and the screw mounting plate 31 from obstructing the movement of the main shoulder 10.

[0025] In one embodiment of the present application, the nut transmission mechanism includes a nut 40 and a nut sleeve 41 that are sleeved on the lead screw 30. The nut 40 is fixed within the nut sleeve 41, so that the nut 40 and the nut sleeve 41 are connected as a whole. The nut 40 and the nut sleeve 41 can be fixedly connected by screws or other methods commonly used in the art, and are not specifically limited here.

[0026] The nut transmission mechanism also includes a reduction disc 42, which is fixedly sleeved on the nut sleeve 41; a top screw fixing device (not shown in the figure) is provided on the reduction disc 42, and the reduction disc 42 is fixedly connected to the nut sleeve 41 through the top screw fixing device, so that the nut 40, the nut sleeve 41 and the reduction disc 42 are connected as a whole, and the rotation of the reduction disc 42 can drive the nut 40 and the nut sleeve 41 to rotate synchronously.

[0027] The nut transmission mechanism also includes a motor 43, which is connected to the main shoulder 10. The output shaft of the motor 43 is connected to the reduction plate 42 via a belt 44. The motor 43 drives the output shaft to rotate, thereby realizing the rotation of the reduction plate 42, thereby realizing the synchronous rotation of the nut 40 and the nut sleeve 41.

[0028] In one embodiment of the present application, a plurality of bearings 46 are further sleeved on the nut sleeve 41. The inner ring of the bearing 46 is fixedly sleeved on the nut sleeve 41 by two stop sleeves 48. The outer ring of the bearing 46 is connected to the nut connecting seat 45 by a top screw. The nut connecting seat 45 does not rotate synchronously with the nut sleeve 41. By providing multiple bearings 46, the nut sleeve 41 can be rotated smoothly and effectively, and the rotation of the nut sleeve 41 can be converted into linear movement, so that the nut 40, the nut sleeve 41, the reduction plate 42 and the motor 43 can be linearly moved along the screw 30. Since the motor 43 is installed on the main shoulder 10, when the nut transmission mechanism moves linearly along the screw 30, it can synchronously drive the main shoulder 10 to move linearly along the screw 30.

[0029] When the main shoulder 10 and the nut transmission mechanism move in a straight line along the guide rail 20 and the lead screw 30, the guide rail 20 is fixed, and the main shoulder 10 and the nut transmission mechanism will apply a force to the lead screw 30. The lead screw 30 will produce a deflection due to the force, making it impossible for the lead screw 30 to maintain absolute parallelism with the extension direction (Y direction) of the guide rail 20. The lead screw 30 will produce a certain deflection in the XY plane and the YZ plane due to the force, causing the lead screw 30 to deviate from the extension direction (Y direction) of the guide rail 20 in the XY plane and the YZ plane, thereby affecting the transmission accuracy of the main shoulder 10. In addition, there will be installation errors in the lead screw 30 during the installation process, causing the lead screw 30 to deviate left and right and / or up and down in the Y direction, resulting in the lead screw 30 being unable to maintain absolute parallelism with the Y direction. For this reason, the lead screw transmission mechanism of the present application is designed with a swing elimination member, which is used to slow down and eliminate the deflection of the lead screw 30 to improve transmission accuracy and stability.

[0030] The swing elimination member is integrally mounted on the nut transmission mechanism and / or the main shoulder 10 , and the swing elimination member moves linearly along with the nut transmission mechanism and the main shoulder 10 .

[0031] like Figure 1、 Figure 2 、 Figures 8-11 As shown, the swing elimination member includes an XY swing elimination member, and the XY swing elimination member includes an XY swing block 51. The XY swing block 51 is provided with an XY matching groove 55. An XY bearing is provided in the XY matching groove 55. The inner ring of the XY bearing is fixed with an XY swing axis 53, and the XY swing axis 53 is parallel to the Z direction.

[0032] The swing elimination member includes a YZ swing elimination member, which includes a YZ swing block 52. The YZ swing block 52 is provided with a YZ matching groove 56. A YZ bearing is provided in the YZ matching groove 56. The inner ring of the YZ bearing is fixed with a YZ swing shaft 54. The YZ swing shaft 54 ​​is parallel to the X direction.

[0033] The YZ swing block 52 is equipped with two protruding, parallel, and spaced-apart connecting plates 57, with the XY swing block 51 positioned between them. The two connecting plates 57 are each provided with corresponding first mounting holes 58, into which the ends of the XY swing axis 53 are secured. The securing method can be commonly used in the art and is not specifically limited here. The above-described coupling of the XY swing block 51 and the YZ swing block 52 connects the XY and YZ swing eliminators, resulting in a compact, small, and space-saving structure.

[0034] The swing elimination member also includes a mounting groove, and the YZ swing elimination member is installed on the main shoulder 10 through the mounting groove. Specifically: in one embodiment of the present application, the mounting groove is connected to the main shoulder 10, and the mounting groove is an integral part, which includes a first mounting plate 61, and the two ends of the first mounting plate 61 are respectively vertically provided with a second mounting plate 62 and a third mounting plate 63. The first mounting plate 61, the second mounting plate 62 and the third mounting plate 63 form a U-shaped open groove structure, and its opening is facing the linear movement direction of the nut transmission mechanism.

[0035] The YZ swing block 52 is located between the second mounting plate 62 and the third mounting plate 63; corresponding second mounting holes 64 are provided on the second mounting plate 62 and the third mounting plate 63, and the two ends of the YZ swing shaft 54 ​​are respectively fixed in the two second mounting holes 64; the fixing method can be a common fixing method in this technical field and is not specifically limited here.

[0036] The swing elimination member also includes a fourth mounting plate 65, and the XY swing elimination member is installed on the nut transmission mechanism through the fourth mounting plate 65. Specifically: the fourth mounting plate 65 is fixedly connected to the XY swing block 51, and the fourth mounting plate 65 is fixed on the outer surface of the nut connecting seat 45. The fixed connection method can be a bolt connection, and no specific limitation is made here.

[0037] In one embodiment of the present application, the transmission mechanism of the present application further includes a transmission housing. The transmission housing is a single piece and includes a first shell plate 71 and a second shell plate 72, which are perpendicular to each other. The first shell plate 71 is arranged parallel to the top of the guide rail 20 and can be connected to the main shoulder 10. The second shell plate 72 is arranged vertically on one side of the guide rail 20. The motor 43 is connected to the top surface of the first shell plate 71 via the motor mounting plate 47, and the third mounting plate 63 can be connected to the inner side surface of the second shell plate 72 via bolts. By providing the transmission housing, the swing elimination member can be covered, thereby making the screw transmission structure of the present application simple and beautiful.

[0038] When the nut 40 drives the nut connecting seat 45 to move linearly (the nut connecting seat 45 does not rotate, but only moves linearly following the nut 40), the nut connecting seat 45 will generate a driving force, which is neither parallel to the XY plane nor to the YZ plane; the driving force is first transmitted to the XY swing elimination member, and the XY swing elimination member transmits the force to the XY swing axis 53; in the XY plane, the driving force is the radial force of the XY swing axis 53, and the XY swing axis 53 is deflected by this radial force. During the deflection process, the radial force that is not parallel to the YZ plane will be filtered out by the deflection, leaving only the force parallel to the YZ plane. The remaining force parallel to the YZ plane is transmitted to the YZ swing eliminator, and the YZ swing eliminator transmits the force to the YZ swing axis 54; since the YZ swing axis 54 and the XY swing axis 53 are perpendicular to each other, the force parallel to the YZ plane causes the YZ swing axis 54 to deflect, and the radial force not parallel to the XY plane is filtered out by the deflection, leaving only the radial force parallel to both the YZ plane and the XY plane.

[0039] In summary, the wobble-eliminating element can eliminate errors in actual assembly of the lead screw 30 and the deflection caused by forces acting on the lead screw 30. The wobble-eliminating element is connected to the transmission housing, driving the transmission housing to move linearly along the guide rail 20 (the Y direction) under the action of a force parallel to the guide rail 20. This, in turn, drives the transmission housing and the main shoulder 10 to move linearly along the guide rail 20, thereby improving the accuracy of the linear movement of the main shoulder 10.

[0040] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for a person skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to replace some of the technical features therein with equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions claimed to be protected by the present invention.

Claims

1. A transmission mechanism used in a gantry coordinate measuring machine, characterized in that: include: main shoulder; a lead screw disposed at the bottom of the main shoulder; The nut transmission mechanism comprises: A nut and a nut sleeve are sleeved on the lead screw, and the nut is fixed in the nut sleeve; A speed reduction plate, fixedly sleeved on the nut sleeve; A motor is mounted on the main shoulder and is used to drive the reduction plate to rotate; the rotation of the reduction plate drives the nut, the nut sleeve, the motor and the main shoulder to move linearly along the lead screw; The swing eliminating member is used to slow down the swing of the lead screw.

2. The transmission mechanism for a gantry coordinate measuring machine according to claim 1, wherein: It also includes a guide rail, the main shoulder is arranged above the guide rail, and an air bearing is provided at the bottom of the main shoulder.

3. The transmission mechanism for a gantry coordinate measuring machine according to claim 2, wherein: The lead screw is mounted on the guide rail via a lead screw mounting plate, and the lead screw extends along the direction of the guide rail.

4. The transmission mechanism for a gantry coordinate measuring machine according to claim 1, wherein: The nut transmission mechanism further comprises a bearing, the inner ring of the bearing is fixed on the nut sleeve, and the outer ring of the bearing is fixed with a nut connecting seat.

5. The transmission mechanism for a gantry coordinate measuring machine according to claim 1, wherein: The motor is mounted on a motor mounting plate, and the motor mounting plate is connected to the main shoulder.

6. The transmission mechanism for a gantry coordinate measuring machine according to claim 1, wherein: The swing eliminating member includes an XY swing eliminating member, which includes an XY swing block, and the XY swing block is connected to the nut transmission mechanism; The XY swing block is provided with an XY matching groove, an XY bearing is provided in the XY matching groove, and an XY swing shaft is fixed to the inner ring of the XY bearing.

7. The transmission mechanism for a gantry coordinate measuring machine according to claim 6, wherein: The wobble eliminater includes a YZ wobble eliminater including a YZ wobble block, the YZ wobble block being connected to the main shoulder; The YZ swing block is provided with a YZ matching groove, a YZ bearing is provided in the YZ matching groove, and a YZ swing shaft is fixed to the inner ring of the YZ bearing.

8. The transmission mechanism for a gantry coordinate measuring machine according to claim 7, wherein: The XY swing axis and the YZ swing axis are perpendicular to each other, and both the XY swing axis and the YZ swing axis are perpendicular to the axial direction of the lead screw.

9. The transmission mechanism for a gantry coordinate measuring machine according to claim 7, wherein: The swing elimination member includes a mounting slot connected to the main shoulder; The mounting slot includes a first mounting plate, and a second mounting plate and a third mounting plate are respectively vertically provided at both ends of the first mounting plate; the YZ swing block is installed between the second mounting plate and the third mounting plate, and corresponding second mounting holes are provided on the second mounting plate and the third mounting plate, and the two ends of the YZ swing axis are respectively fixed in the two second mounting holes.

10. The transmission mechanism for a gantry coordinate measuring machine according to claim 7, wherein: The YZ swing block is provided with two parallel and spaced connecting plates, and the XY swing block is located between the two connecting plates; corresponding first mounting holes are provided on the two connecting plates, and the two ends of the XY swing axis are respectively fixed in the two first mounting holes.

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