CN114619287A

CN114619287A - Moment anti-interference mechanism of multi-loop rotating shaft

Info

Publication number: CN114619287A
Application number: CN202111301284.4A
Authority: CN
Inventors: 安红卫; 袁雪斐; 陈关洋
Original assignee: Hangzhou Good Friend Precision Machinery Co Ltd
Current assignee: Youjia International Cnc Machine Tool Co ltd
Priority date: 2021-11-04
Filing date: 2021-11-04
Publication date: 2022-06-14
Anticipated expiration: 2041-11-04
Also published as: CN114619287B

Abstract

The invention discloses a torque anti-interference mechanism of a multi-loop rotating shaft, which comprises a machine tool rotating dividing plate, wherein a mandrel penetrates through the center of the machine tool rotating dividing plate, the mandrel comprises a large end and a small end, and an angle encoder is sleeved on the small end. The multi-bushing partition assembly is used for cladding limiting of the whole mandrel through the multiple bushings connected with each other, and the problem that the mandrel is touched or frictionally sleeved on an angle encoder of the mandrel due to radial displacement generated by centrifugal force in the rotating process of the mandrel is avoided, so that the angle measurement of the angle encoder is influenced.

Description

Moment anti-interference mechanism of multi-loop rotating shaft

Technical Field

The invention relates to the technical field of precision measurement, in particular to a torque anti-interference mechanism of a multi-loop rotating shaft.

Background

The multi-turn index plate of the numerical control machine tool is widely applied to a machining center of the numerical control machine tool. A general machining center only has three axes, namely an X axis, a Y axis and a Z axis, so that three-axis rapid displacement is realized. However, the additional high-precision multi-loop rotating shaft is a rotating index plate which can rotate by a certain angle and is arranged on the working table. The parts machined by using the high-precision multi-loop rotating shaft can be automatically indexed, and the workpiece can rotate on the surface of the workbench by a certain angle. The loss precision of parts is not required to be clamped for the second time, and the processing time can be saved. In the rotary dividing plate of the machine tool, a mandrel is used as a passage for the external hydraulic oil circuit to enter and exit, and hydraulic oil enters the mandrel from an oil circuit distributor on the left side of the mandrel. Firstly, the method comprises the following steps: the mandrel body is of a large end structure and a small end structure, the side close to the large end rotates along with the dividing disc, and the small end is far away from the large end; this may make the small end portion of the spindle susceptible to rubbing against the gonio-optic scale due to centrifugal forces during rotation of the spindle. Secondly, the method comprises the following steps: the inside hydraulic oil that passes through of dabber can rise gradually along with the temperature of carrying out inside hydraulic oil of work, leads to the dabber tip thermal expansion, and the external diameter grow also contacts easily and rubs the angle optical ruler.

For example, a "turning and grinding center for a machine tool" disclosed in chinese patent document, which is disclosed under the publication number "CN 111112757A," is composed of a three-dimensional dragging unit, a horizontal rotary table, a vertical rotary table, and a U-axis machining and feeding unit; an electric tool magazine, a manipulator device and an automatic detection device are configured; a Siemens 840Dsl control system is adopted to realize six-axis five-linkage; each linear shaft is provided with a linear grating ruler, and the rotating shaft adopts a high-resolution angle encoder, so that the precision of the machine tool is improved through closed-loop control.

According to the scheme, in use, friction between the mandrel and the grating ruler can occur due to rotation of the mandrel, the read data of the optical ruler can be influenced, and the final angle position data fed back and compensated by the optical ruler can be inaccurate, so that the actual machining precision of the workpiece can be influenced.

Disclosure of Invention

Aiming at solving the problem that a mandrel and an optical ruler have friction due to the optimization of the internal structure of a rotary dividing disc additionally provided with a multi-channel multi-loop device, the invention provides a torque anti-interference mechanism of a multi-loop rotary shaft.

The second invention aims to solve the problem that the measurement accuracy of the grating ruler is influenced by heat expansion caused by friction heat generation and heat of an internal oil path in the working process of the mandrel.

In order to achieve the purpose, the invention adopts the following technical scheme:

the moment anti-interference mechanism of the multi-loop rotating shaft comprises a machine tool rotating dividing plate, wherein a mandrel penetrates through the center of the machine tool rotating dividing plate, the mandrel comprises a large end and a small end, and an angle encoder is sleeved on the small end. The multi-bushing partition assembly is used for cladding limiting of the whole mandrel through the multiple bushings connected with each other, and the problem that the mandrel is touched or frictionally sleeved on an angle encoder of the mandrel due to radial displacement generated by centrifugal force in the rotating process of the mandrel is avoided, so that the angle measurement of the angle encoder is influenced.

Preferably, the end face of the rotary dividing disc of the machine tool is provided with a mounting groove, the joint of the large end and the small end comprises a shaft end face, and the rear end face of the angle encoder is abutted to the shaft end face; many bushes cut off subassembly includes first bush, second bush and third bush, terminal surface before first bush registrates in tip and butt, third bush registrates the tip and sets up in angle encoder's rear end face rear, the second bush cup joints outside the tip, the second bush runs through and sets up in angle encoder, first bush and second bush are connected respectively to the both ends of second bush. The dabber runs through and sets up in whole lathe gyration graduated disk, and angle encoder cup joints in the tip of dabber, if the direct mount, if after the beginning work, in case dabber and angle encoder take place the friction and will influence the reading data of optical ruler, the final angular position data that feedback compensation was come of optical ruler will be inaccurate and then can influence the actual machining precision of work piece. Therefore, the front end of the angle encoder is positioned through the first bushing, the second bushing penetrates through the angle encoder to eliminate radial pushing force from the core shaft, the third bushing is connected with a rotary dividing plate of the machine tool, and meanwhile, the third bushing is used as a base of the second bushing, so that the multi-bushing partition assembly of the third bushing, the second bushing and the first bushing is realized, radial pushing generated by rotation of the core shaft is effectively avoided, and the measurement of the angle encoder is ensured not to be interfered.

Furthermore, the angle encoder center is provided with the mounting hole, the second bush is including the cover body and set up in the base disc of set body rear end, set body cover is located in the mounting hole, is provided with the assembly groove on the preceding terminal surface of angle encoder, the assembly groove sets up with the mounting hole is concentric, assembly groove and fixed connection angle encoder are connected to first bush block.

Furthermore, the first bush is sleeved at the front end of the sleeve body, and the third bush is fixedly connected with the base plate.

Further, the machine tool rotary index plate is in interference connection with a third bushing.

The second bush is connected with the third bush through the base plate, the third bush is in interference connection with the rotary dividing plate of the machine tool, the design can ensure that the second bush can limit the mandrel in the sleeve body in the rotating process of the mandrel, the limiting effect is strengthened by connecting the third bush, the radial swing possibly generated by the mandrel is cut off, and the possibility of a friction angle encoder of the mandrel is eliminated.

Preferably, a stress relief cavity is arranged at the joint of the base plate and the sleeve body, a balance rod is arranged in the stress relief cavity along the radial direction, one end of the balance rod is connected with the small end, and a counterweight is arranged at the other end of the balance rod. The balance rod and the balance weight part are matched to rotate along with the rotation of the mandrel, and the centrifugal force generated by the rotation of the balance rod and the balance weight part after combination is the same as the radial pressure borne by the first bushing. Specifically, when the mandrel rotates, although the first bushing is arranged at the joint of the small end and the angle encoder, because the small end is not completely fixed, the mandrel is still pushed by a radial centrifugal force in the whole rotation process of the mandrel, the first bushing can still be driven by the centrifugal force to radially move, the radial movement acts on the second bushing to generate stress concentration at the joint of the base plate and the sleeve body, the second bushing is broken at the joint of the base plate and the sleeve body due to fatigue after long-term operation, once the second bushing is broken, the mandrel limiting function of the multi-bushing partition assembly fails, and the mandrel can continue to rub the angle encoder to interfere measurement, so the problem needs to be solved by adopting the scheme that a stress relief cavity is additionally arranged at the joint of the base plate and the sleeve body, the stress concentration at the step can be avoided firstly, and then the balancing rod and the balancing weight synchronously rotate, the balancing pole rotates with the balancing weight synchronous produced centrifugal force of first bush position mutually balanced for the second bush needn't bear the moment of flexure that unilateral tip centrifugal force produced, but keeps axial stress balance on the length of whole cover body, greatly promotes the life of second bush.

Preferably, the counterweight is provided with a guide vane, and the guide vane coaxially rotates along with the counterweight. The guide vane can effectively help the dissipation of mandrel heat in the synchronous rotation process along with the counterweight, so that the mandrel is always maintained in a proper temperature range, and the problem that the mandrel is overheated to expand to cause friction interference to the angle encoder is avoided.

Preferably, a through hole is formed in one side, close to the mandrel, of the stress relief cavity, the balance rod extends from the mandrel through the through hole to the stress relief cavity, and an oil seal ring is arranged in the through hole. The oil seal ring is used for preventing the lubricant in the second bushing from entering the stress relief cavity along with the rotation of the mandrel, so that the reduction of the lubricating effect between the mandrel and the second bushing is avoided, and the condition that the lubricant adheres to the guide vane to influence the heat dissipation effect is avoided.

Preferably, the second bushing is made of a copper-aluminum alloy. The second bush is used as a bridge piece between the first bush and the third bush, and is required to have higher hardness to ensure the limiting effect of the mandrel, and meanwhile, the second bush also has excellent heat dissipation performance, so that the mandrel can dissipate heat timely to avoid expansion deformation.

Therefore, the invention has the following beneficial effects: (1) the multi-bushing partition assembly is used for cladding limiting on the whole mandrel through the plurality of bushings connected with each other, so that the problem that the mandrel touches or rubs an angle encoder sleeved on the mandrel due to radial displacement generated by centrifugal force in the rotating process of the mandrel is avoided, and the angle measurement of the angle encoder is influenced; (2) the stress relief cavity is additionally arranged at the joint of the base plate and the sleeve body, so that stress concentration at the step part of the base plate connected with the sleeve body can be avoided; (3) the stress relief cavity is additionally arranged at the joint of the base plate and the sleeve body, so that the second bushing does not need to bear bending moment generated by centrifugal force at the end part of one side, axial stress balance is kept on the length of the whole sleeve body, and the service life of the second bushing is greatly prolonged; (4) the guide vane can effectively help the heat dissipation of the mandrel in the synchronous rotation process along with the counterweight, so that the mandrel is always maintained in a proper temperature range, the problem that the mandrel is subjected to friction interference on the angle encoder due to overheating expansion is avoided, and the second purpose of the invention is effectively achieved.

Drawings

FIG. 1 is a side cross-sectional view of the present invention.

FIG. 2 is a side cross-sectional view of the first bushing of FIG. 1.

FIG. 3 is a side cross-sectional view of the third bushing of FIG. 1.

Fig. 4 is a side cross-sectional view of the second bushing of fig. 1.

Fig. 5 is a partially enlarged view of a portion a in fig. 1.

In the figure: 1. the rotary indexing disc of the machine tool comprises a rotary indexing disc 11, a mounting groove 2, a mandrel 21, a large end 22, a small end 23, a shaft end face 24, an oil way 3, a multi-bush partition assembly 4, a first bush 5, a second bush 51, a sleeve body 52, a base disc 53, a stress relief chamfer 6, a third bush 7, a stress relief cavity 71, a balance rod 72, a through hole 73, an oil seal ring 8, a counterweight 9 and a guide vane.

Detailed Description

The invention is further described with reference to the following detailed description and accompanying drawings.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or may be connected through the use of two elements or the interaction of two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

Example 1

As shown in fig. 1, the torque anti-interference mechanism of the multi-loop rotating shaft comprises a machine tool rotating index plate 1, wherein a mandrel 2 penetrates through the center of the machine tool rotating index plate 1, the mandrel 2 comprises a large end 21 and a small end 22, and an angle encoder is sleeved on the small end 22, and the torque anti-interference mechanism is characterized in that a multi-bush partition component 3 is arranged between the angle encoder and the mandrel 2. The end face of the machine tool rotary dividing disc 1 is provided with a mounting groove 11, the joint of the large end 21 and the small end 22 comprises a shaft end face 23, and the rear end face of the angle encoder is abutted to the shaft end face 23; as shown in fig. 2, 3 and 4, the multi-bush partition assembly 3 includes a first bush 4, a second bush 5 and a third bush 6, the first bush 4 is sleeved on the small end 22 and abuts against the front end face, the third bush 6 is sleeved on the large end 21 and is arranged behind the rear end face of the angle encoder, the second bush 5 is sleeved outside the small end 22, the second bush 5 is arranged in the angle encoder in a penetrating manner, and two ends of the second bush 5 are respectively connected with the first bush 4 and the second bush 5.

The multi-bushing partition component 3 is used for cladding limiting on the whole mandrel 2 through the multiple bushings connected with each other, and the problem that the mandrel 2 touches or is frictionally sleeved on an angle encoder of the mandrel 2 due to radial displacement generated by centrifugal force in the rotating process is avoided, so that the angle measurement of the angle encoder is influenced. The spindle 2 penetrates through the whole machine tool rotary dividing disc 1, the angle encoder is sleeved at the small end 22 of the spindle 2, if the spindle is directly installed, after the spindle 2 and the angle encoder start to work, once friction occurs between the spindle 2 and the angle encoder, reading data of the optical ruler can be influenced, and the final feedback compensation of the optical ruler on the angle position data can be inaccurate, so that the actual machining precision of a workpiece can be influenced. Therefore, the front end of the angle encoder is positioned through the first bushing 4, the second bushing 5 penetrates through the angle encoder to eliminate radial pushing force from the core shaft 2, the third bushing 6 is connected with the rotary dividing plate 1 of the machine tool, and meanwhile, the third bushing 6 is used as a base of the second bushing 5, so that the multi-bushing partition assembly 3 of the third bushing 6, the second bushing 5 and the first bushing 4 is realized, the radial pushing generated by the rotation of the core shaft 2 is effectively avoided, and the measurement of the angle encoder is ensured not to be interfered.

The angle encoder center is provided with the mounting hole, second bush 5 is including the cover body 51 with set up in the base plate 52 of the cover body 51 rear end, in the mounting hole was located to the cover body 51 cover, be provided with the assembly groove on the preceding terminal surface of angle encoder, the assembly groove sets up with the mounting hole is concentric, assembly groove and fixed connection angle encoder are connected to first bush 4 block. The first bush 4 is sleeved at the front end of the sleeve body 51, and the third bush 6 is fixedly connected with the base plate 52. The machine tool rotary indexing disc 1 is in interference connection with a third bushing 6,

the second bush 5 is connected with the third bush 6 through the base disc 52, and the third bush 6 is connected with the machine tool rotation dividing disc 1 in an interference mode, the design can ensure that the second bush 5 can limit the mandrel 2 in the bush in the rotation process of the mandrel 2, the limiting effect is strengthened by connecting the third bush 6, the radial swing which is possibly generated by the mandrel 2 is cut off, and the possibility of a friction angle encoder of the mandrel 2 is eliminated.

A stress relief cavity 7 is arranged at the joint of the base plate 52 and the sleeve body 51, a balance rod 71 is arranged in the stress relief cavity 7 along the radial direction, one end of the balance rod 71 is connected with the small end 22, and the other end of the balance rod is provided with a counterweight 8. The balance bar 71 and the balance weight 8 are matched to rotate along with the rotation of the mandrel 2, and the centrifugal force generated by the rotation of the balance bar and the balance weight after combination is the same as the radial pressure borne by the first bushing 4. Specifically, when the mandrel 2 rotates, although the first bushing 4 is disposed at the joint of the small end 22 and the angle encoder, because the small end 22 is not completely fixed, the mandrel 2 is still pushed by a radial centrifugal force during the entire rotation of the mandrel 2, so the first bushing 4 still drives the mandrel 2 to move radially under the action of the centrifugal force, the radial movement acts on the second bushing 5 to generate stress concentration at the joint of the base plate 52 and the sleeve 51, the second bushing 5 is rapidly fractured at the joint of the base plate 52 and the sleeve 51 due to fatigue after long-term operation, and once the fracture occurs, the limiting function of the mandrel 2 of the multi-bushing partition assembly 3 fails, the mandrel 2 continues to rub the angle encoder to interfere measurement, so the problem needs to be solved, and the solution adopted is to add the stress relief cavity 7 at the joint of the base plate 52 and the sleeve 51, and firstly avoid stress concentration at a step, secondly, through the synchronous rotation of the balancing pole 71 and the balancing weight, the centrifugal force at the position of the first bush 4 generated by the synchronous rotation of the balancing pole 71 and the balancing weight is balanced, so that the second bush 5 does not need to bear the bending moment generated by the centrifugal force at the end part of the single side, the axial stress balance is kept on the length of the whole sleeve body 51, and the service life of the second bush 5 is greatly prolonged. In addition, in the embodiment, the stress relief chamfer 53 is further arranged at the tail part of the sleeve body close to the stress relief cavity, so that stress concentration caused by a right-angle structure at a step can be effectively avoided, and the anti-fatigue capability and the service life of the second bushing are further improved.

It should be noted that, in the present embodiment, since the plurality of oil paths 24 are arranged in the mandrel 2, the temperature of the hydraulic oil passing through the mandrel 2 gradually increases as the work progresses. In the solution, guide vanes 9 are provided on the weight 8, said guide vanes 9 rotating coaxially with the weight 8. As shown in fig. 5, the guide vane 9 can effectively help the heat dissipation of the mandrel 2 in the process of synchronously rotating along with the counterweight 8, so that the mandrel 2 is always maintained in a proper temperature range, and the mandrel 2 is prevented from being overheated and expanded to avoid friction interference with the angle encoder. A through hole 72 is formed in one side, close to the mandrel 2, of the stress relieving cavity 7, the balance rod 71 extends from the mandrel 2 through the through hole 72 to the stress relieving cavity 7, and an oil seal ring 73 is arranged in the through hole 72. The oil seal ring 73 is used for preventing the lubricant in the second liner 5 from entering the stress relief cavity 7 along with the rotation of the mandrel 2, so that the reduction of the lubricating effect between the mandrel 2 and the second liner 5 is avoided, and the condition that the lubricant adheres to the guide vane 9 to influence the heat dissipation effect is avoided. In this embodiment, the second bushing 5 is made of a copper-aluminum alloy. Second bush 5 is as the bridge spare between first bush 4 and third bush 6, need to possess higher hardness in order to guarantee the spacing effect of dabber 2, also should possess good heat dispersion simultaneously, and the dabber 2 of being convenient for dispels the heat in time and avoids the bulging deformation, further reduces the dabber 2 interference that produces angle sensor in the operation process.

In addition to the above embodiments, the technical features of the present invention may be reselected and combined to form a new embodiment within the scope of the claims of the present invention and the specification, which are all achieved without creative efforts of those skilled in the art, and thus, the embodiments of the present invention not described in detail should be regarded as specific embodiments of the present invention and are within the protection scope of the present invention.

Claims

1. The moment anti-interference mechanism of the multi-loop rotating shaft comprises a machine tool rotating dividing plate, wherein a mandrel penetrates through the center of the machine tool rotating dividing plate, the mandrel comprises a large end and a small end, and an angle encoder is sleeved on the small end.

2. The torque interference resisting mechanism of the multi-loop rotating shaft according to claim 1, wherein an installation groove is formed in the end face of the rotating dividing plate of the machine tool, the joint of the large end and the small end comprises a shaft end face, and the rear end face of the angle encoder is abutted to the shaft end face; many bushes cut off subassembly includes first bush, second bush and third bush, terminal surface before first bush registrates in tip and butt, third bush registrates the tip and sets up in angle encoder's rear end face rear, the second bush cup joints outside the tip, the second bush runs through and sets up in angle encoder, first bush and second bush are connected respectively to the both ends of second bush.

3. The torque anti-interference mechanism of the multi-loop rotating shaft as claimed in claim 2, wherein the angle encoder has a mounting hole at the center thereof, the second bushing includes a sleeve and a base plate disposed at the rear end of the sleeve, the sleeve is sleeved in the mounting hole, the front end surface of the angle encoder has an assembling groove, the assembling groove is concentric with the mounting hole, and the first bushing is engaged with the assembling groove and fixedly connected with the angle encoder.

4. The torque anti-interference mechanism of a multi-circuit rotating shaft according to claim 3, wherein said first bushing is sleeved on the front end of the sleeve body, and said third bushing is fixedly connected to the base plate.

5. The torque interference rejection mechanism for a multi-circuit rotary shaft as claimed in claim 2, wherein said machine tool rotary index plate is interference coupled to said third bushing.

6. The torque interference rejection mechanism of a multi-loop rotating shaft as claimed in claim 3, wherein a stress relief cavity is formed at the joint of said base plate and said sleeve, a balance bar is radially disposed in said stress relief cavity, one end of said balance bar is connected to said small end, and the other end of said balance bar is provided with a weight.

7. The torque interference rejection mechanism for a multi-circuit rotating shaft as claimed in claim 6, wherein said weight member has a guide vane thereon, said guide vane rotating coaxially with said weight member.

8. The torque interference rejection mechanism for a multi-circuit rotating shaft as claimed in claim 6, wherein a through hole is formed in a side of said stress-relief cavity adjacent to said mandrel, said balancing rod extends from said mandrel through said through hole to said stress-relief cavity, and an oil seal ring is disposed in said through hole.

9. The torque interference mechanism of a multi-circuit rotating shaft according to any one of claims 2 to 8, wherein said second bushing is made of copper-aluminum alloy.