CN110594385A

CN110594385A - Vacuum chamber dynamic seal driving assembly

Info

Publication number: CN110594385A
Application number: CN201911009466.7A
Authority: CN
Inventors: 宋德鹏; 于涛
Original assignee: Ji'nan Li Li Electronic Technology Co Ltd
Current assignee: Ji'nan Li Li Electronic Technology Co Ltd
Priority date: 2019-10-23
Filing date: 2019-10-23
Publication date: 2019-12-20

Abstract

The invention discloses a vacuum chamber dynamic seal driving assembly, the basic structure of which comprises: the pipe frame is a straight pipe body, the axial direction of the straight pipe body is a preset linear motion direction, and one end of the straight pipe body is fixedly connected with the vacuum chamber; the linear driving part is fixedly installed at the other end of the pipe frame; a pallet located in the pipe frame and driven by an output member of the linear driving part; the support rod is arranged on the supporting plate through a first bearing and is a driving object of the driving assembly; the key sleeve is arranged in the pipe frame through the second bearing and is connected with the support rod in a key mode, so that the support rod has axial freedom degree and circumferential freedom degree based on the key sleeve; and a rotation driving part which is arranged on the pipe frame and outputs and drives the key sleeve so as to enable the supporting rod to have preset rotation motion. The driving assembly provided by the invention has a better sealing effect under the condition of realizing compound motion.

Description

Vacuum chamber dynamic seal driving assembly

Technical Field

The invention relates to a vacuum chamber dynamic seal driving assembly.

Background

The dynamic seal is always a technical direction which is difficult to solve in the mechanical field, and along with the development of the technology, certain directions of the dynamic seal are well solved, for example, the dynamic seal in linear motion can adopt a welded corrugated pipe, the axial direction of the welded corrugated pipe is the direction of the linear motion, and the static seal under the motion condition can be realized based on the flexibility of the welded corrugated pipe. For the rotary motion, in the earlier application, the contact seal mainly adopts packing, shaft seal and the like for sealing, and in the non-contact seal, the seal structures such as labyrinth seal, thread pair seal, magnetic fluid seal and the like are mainly adopted for sealing. For compound motions, i.e. forms of motion that involve both linear and rotational motion, the sealing is relatively difficult to achieve and currently there is no good solution.

For example, labyrinth seals have relatively high positional requirements for structures to which the seal is fitted, and cannot achieve linear dynamic sealing under the condition of achieving rotary sealing. In comparison, the magnetic fluid seal in the recombination dynamic seal application has better improvement prospect. However, the current applications for magnetic fluid seals are also primarily for purely rotary seals.

Typically, as chinese patent documents CN208089802U and CN110082141A, etc., the applied scenes are all rotary dynamic seals, and dynamic seals under the condition of compound motion cannot be realized.

Disclosure of Invention

In view of the above, the present invention is directed to a dynamic seal driving assembly for a vacuum chamber, which has a dynamic seal structure under a composite motion condition.

In an embodiment of the present invention, a vacuum chamber dynamic seal driving assembly is provided, the basic structure of which comprises:

the pipe frame is a straight pipe body, the axial direction of the straight pipe body is a preset linear motion direction, and one end of the straight pipe body is fixedly connected with the vacuum chamber;

the linear driving part is fixedly installed at the other end of the pipe frame;

a pallet located in the pipe frame and driven by an output member of the linear driving part;

the support rod is arranged on the supporting plate through a first bearing and is a driving object of the driving assembly;

the key sleeve is arranged in the pipe frame through the second bearing and is connected with the support rod in a key mode, so that the support rod has axial freedom degree and circumferential freedom degree based on the key sleeve; and

and the rotation driving part is arranged on the pipe frame and outputs and drives the key sleeve so as to enable the supporting rod to have preset rotation motion.

Optionally, the linear driving part comprises a first power compartment, and a first sealing structure is formed between the first power compartment and the pipe frame.

Optionally, the linear driving part comprises a screw rod with one end mounted on the first power compartment through a third bearing and a nut mounted on the supporting plate and forming a nut screw mechanism with the screw rod;

a seat plate is fixedly arranged in the pipe frame, and the other end of the lead screw is arranged on the seat plate through a fourth bearing;

correspondingly, the axial direction of the screw rod is parallel to the axial direction of the pipe frame.

Optionally, there are two lead screws, and the two lead screws are symmetrical with respect to the axis of the support rod.

Optionally, the first bearing is a cardan bearing.

Optionally, a driving component of the linear driving portion is mounted outside the first power compartment, and the driving component and the first power compartment are mounted on the first power compartment through a magnetic fluid sealing device.

Optionally, the key sleeve is a splined sleeve or a flat key sleeve.

Optionally, the rotary driving part is positioned in the middle of the pipe frame and comprises a second power cabin;

the pipe support is of a multi-section structure, and corresponding pipe sections and the second power cabin form flange connection at the position of the second power cabin.

Optionally, the rotation driving part includes:

a driven member fixedly mounted on the key sleeve;

the driving component is matched with the driven component to form an output pair;

and the rotary driving motive power piece is positioned outside the second power cabin, and an output part is matched with the driving component and forms rotary dynamic seal with the second power cabin.

Optionally, the driven member is a turbine or a driven bevel gear;

correspondingly, the driving component is a worm matched with the worm wheel or a driving bevel gear matched with the driven bevel gear;

the gear shaft of the worm or the driving bevel gear is vertical to the linear motion direction.

In an embodiment of the present invention, a pipe frame is provided, the pipe frame is provided with a pipe cavity, a driven supporting rod is arranged in the pipe cavity, the supporting rod is arranged on a supporting plate capable of moving in the axial direction of the pipe cavity through a bearing, and therefore, under the condition that the supporting plate has a linear motion form, the supporting rod and the supporting plate are assembled through the bearing, so that the supporting rod has a rotational freedom degree, in other words, the supporting rod has rotational freedom degree and a linear motion freedom degree. Wherein, the linear motion of the supporting rod is realized in a linear driving part arranged at the other end of the pipe frame, which directly drives the supporting plate, and only needs to consider single linear motion dynamic seal or rotary dynamic seal (supposing that an intermediate mechanism for converting rotation into linear motion exists) between the supporting plate and the pipe frame at most; and to the realization of the rotary motion of the die-pin, then set up a key sleeve in the pipe support, the key sleeve is installed in the pipe support through the bearing and has the rotational degree of freedom, and pass through the key joint between die-pin and key sleeve, its linear motion degree of freedom does not receive the influence of key sleeve, and the key joint belongs to the typical circumferential connection of mechanical field, can drive the die-pin to rotate when the key sleeve is driven, and to the rotary drive portion, it only has single rotary dynamic seal or linear motion dynamic seal with the pipe support at most. The composite driving of the supporting rod can be realized, and in the embodiment of the invention, under the condition of realizing the composite movement of the supporting rod, at most one sealing form is generated between each driving part and the pipe frame, and the method is easy to realize based on the prior art.

Drawings

FIG. 1 is a schematic front view of a vacuum chamber dynamic seal driving assembly according to an embodiment.

Fig. 2 is a sectional view a-a of fig. 1.

Fig. 3 is a sectional view B-B of fig. 1.

In the figure: 1. the automatic transmission comprises a first power compartment, 2 parts of a driven belt pulley, 3 parts of a lead screw, 4 parts of a universal joint bearing, 5 parts of a nut, 6 parts of a first pipeline, 7 parts of a support rod, 8 parts of a seat plate, 9 parts of a bearing, 10 parts of a spline sleeve, 11 parts of a second pipeline, 12 parts of a flange, 13 parts of a vacuum cavity, 14 parts of a third pipeline, 15 parts of a worm wheel, 16 parts of a second power compartment, 17 parts of a second motor, 18 parts of a support plate, 19 parts of a first motor, 20 parts of a magnetic fluid sealing device, 21 parts of a worm, 22 parts of a magnetic fluid sealing device, 23 parts of a synchronous belt and 24 parts of a driving belt.

Detailed Description

The structure shown in figure 1 is a vertical structure, it being understood that for the vacuum chamber 13, the more demanding of the power introduction structure is a horizontal introduction, but vertical introduction is not excluded; furthermore, even if introduced vertically, the motive portion may be located above the vacuum chamber 13, or below the vacuum chamber 13, and thus the structure shown in fig. 1 may be in the illustrated state, or in a state rotated 90 degrees, 180 degrees, or 270 degrees counterclockwise in the specific design.

In the foregoing technical conditions, for convenience of description, the embodiment of the present invention is explained by taking the orientation in fig. 1 as the basic orientation, and thereby, other structural configurations of the dynamic sealing driving assembly of the vacuum chamber 13 can be easily understood by those skilled in the art.

In fig. 1, the first pipe 6 and the second pipe 11 are connected in series to form a pipe frame, the structure shown in the figure is used for schematically illustrating the structure and principle of the invention, and the understanding of the pipe frame can also include a third pipe 14 in fig. 1. A welding flange on the vacuum chamber 13 can also be indicated for the third pipe 14.

While the second power pod 16 as shown in fig. 1 can also be understood as a constituent part of the pipe rack, likewise the second power pod 16 can also be understood as a connecting part for connecting the first pipeline 6 with the second pipeline 11, and also as a separate part.

As for the pipe frame, it can be understood as a pipe body structure as a whole, preferably a round pipe body, which has a pipe cavity, the sealing of the pipe cavity is based on the sealing of the vacuum chamber 13 under the condition of power introduction, and the sealing of the pipe frame is mainly end sealing, wherein, as shown in fig. 1, the sealing between the second pipeline 11 and the third pipeline 14 belongs to static sealing, and belongs to sealing which is easy to realize, while the invention focuses on solving the problem of dynamic sealing, therefore, in the embodiment of the invention, only the position of the static sealing part is indicated, and the description is omitted.

If the pipe support is designed as a multi-segment pipe support, at least some of the pipe segments may be detachably connected to other pipe segments or to the vacuum chamber 13, for example by flange connections.

The fitting relationship between the multiple sections is preferably a detachable structure based on, for example, the configuration of the first power pod 1 and the second power pod 16, and a flange connection structure is preferred among the structures shown in fig. 1.

In fig. 1, the pipe frame is a vertical straight pipe body as a whole, and the upper end of the pipe frame is in flange connection with a welding flange part on a vacuum chamber 13, namely a third pipeline 14 shown in the figure. The carrier rods 7 are shown as a generic term for composite motion components that are inserted into the vacuum chamber 13 for driving components within the vacuum chamber 13 or carrying other items.

In the embodiment of the present invention, the compound motion of the supporting rod 7 is realized by two driving parts, wherein the linear motion is realized by a linear driving part, and the rotary motion is realized by a rotary driving part. Wherein the linear driving part is fixedly arranged at the lower end of the pipe frame as shown in figure 1.

There should be no assembly interference and no movement interference between the linear driving part and the rotary driving part, wherein the assembly interference is easily determined, as shown in fig. 1, the linear driving part is located at the lower end of the first pipe 6, and the rotary driving part is located at the upper end of the first pipe 6. For motion interference, it is the first concept to which the present invention relates.

In particular, inside the pipe support, in particular in the configuration shown in figure 1, inside the lumen of the first conduit 6 there is a pallet 18, this pallet 18 being directly driven by the output member of the linear drive.

It should be noted that, because the linear driving part and the rotary driving part are separately arranged, the driving is simply realized, which belongs to one of the most conventional motion forms in the mechanical field in terms of form, no matter whether the component of the linear driving part inserted into the tube cavity is a linear motion component or a rotary motion component, the structure which needs to form a seal with the tube cavity is only one, such as the shaft hole between the piston rod of the hydraulic cylinder and the end plate, wherein the end plate is an end cover for sealing the lower end of the tube cavity. Under the condition, only the dynamic seal under the condition of a linear motion pair is considered, and the sealing form is relatively single and is easy to realize.

If the part of the linear motion part inserted into the lumen is a rotary motion component, such as the screw rod 3 shown in fig. 1, the motion form is also a single rotary motion, and the structure is easy to realize sealing.

It should be noted that the lower part of fig. 1 is a simplified structure, the driven pulley 2 mounted on the portion of the lead screw 3 exposed outside the lumen is not directly shown on the lead screw 3 in the drawing, and the components on the lumen can be considered to be components which are rotated by 90 degrees and then fit under the lumen.

The carrier rod 7, which has a linear movement in the axial direction of the lumen, can be provided with a guide structure, such as a guide sleeve or guide hole, alone, visible at the upper end of the second duct 11, in which the guide sleeve is arranged in the second duct 11 for guiding the carrier rod 7.

It will be understood that the guide sleeve does not constrain the circumference of the carrier bar 7, in other words it can generate friction, but does not constrain the circumferential freedom of the carrier bar 7.

Further, for the carrier bar 7, in some embodiments only one end position determination may be considered, such as the pallet 18 shown in fig. 1, the pallet 18 being used to determine the lower end position of the carrier bar 7 in fig. 1. Since the carrier bar 7 itself can be reliably guided as described above, no separate guide structure can be provided for the carrier plate 18.

Alternatively, a separate guide or structure may be provided for the platform 18 within the lumen.

In the construction shown in fig. 1, the carrier rod 7 is mounted on the carrier plate 18 by means of a first bearing, the load required for the first bearing being a compound load, the first bearing being configured, for example, as an angular contact bearing or as a combination of a thrust bearing and a radial bearing.

In some embodiments, as shown in fig. 1, since there are two lead screws 3, to effectively mitigate the loose synchronization of the drives, the first bearing is configured as a gimbal bearing 4.

In the structure shown in fig. 1, the supporting rod 7 is coaxial with the tube cavity, if a single lead screw 3 is used, additional overturning moment is generated, the guide structure or the guide device of the supporting rod 7 generates additional load on the supporting rod 7, the smoothness of the guide is relatively poor, and therefore, a pair of lead screws 3 is arranged in the structure shown in fig. 1, and correspondingly, a pair of nuts 5 needs to be matched on the supporting plate 18. Under ideal conditions, the two nut screw mechanisms formed by the structure have ideal synchronism, but the actual working condition cannot be in an ideal state, so that the universal joint bearing 4 is adapted to reduce mechanical clamping stagnation generated by the asynchronization of the two nut screws.

A further condition for eliminating the interference of the two driving part movements is that the spline housing 10 has a relatively good transmission reliability as the spline housing 10 shown in fig. 1, but other key housings, such as a flat key housing, may be used, which has a simple structure and a much weaker strength than the spline housing 10.

The key connection is used in the mechanical field for transferring circumferential loads, and can be axially positioned by adopting an auxiliary structure, in other words, under the condition of no auxiliary structure, such as components or structures such as a snap spring, a round nut, a shaft shoulder and the like, the key connection is generally considered not to generate axial limit (except a hook head key) in the mechanical field.

The key housing is mounted in the pipe support by means of a second bearing, and in the embodiment shown in fig. 1, the spline housing 10 has bearings 9 at its upper and lower ends, respectively, and the bearings 9 support the spline housing 10 in the second pipe 11.

After the spline housing 10 and the support rod 7 are connected through a key, the spline housing 10 and the support rod 7 are connected in a circumferential direction, so that the support rod 7 has axial freedom and circumferential freedom based on the support of the bearing 9 to the key housing.

In the case where the rotation driving portion is mounted at the lower end of the pipe frame, the rotation driving portion is directly mounted on the pipe frame, while avoiding the linear driving portion at the mounting position. Accordingly, the output of the rotation driving part drives the key sleeve to make the supporting rod 7 have a predetermined rotation motion.

In the configuration shown in fig. 1, the rotary drive is mounted in the middle of the pipe frame, and on the portion of the pipe frame below the rotary drive, such as the first pipe 6 shown in fig. 1, the pallet 18 has a sufficient stroke of movement, in other words, the axial length of the first pipe 6 is mainly used to determine the stroke of the pallet 18.

In fig. 1 ~ 3, a first power compartment 1 is provided for the linear driving part, the linear driving part is partially or completely accommodated in the first power compartment 1, when the linear driving part is completely accommodated in the first power compartment 1, the relevant sealing structures are static seals, and a magnetic fluid sealing device 20 as shown in fig. 1 is not needed, so that the first motor 19 cannot directly dissipate heat, for example, because the linear driving part is completely installed in the first power compartment 1, in the structure as shown in fig. 1, at least the prime mover in the linear driving part, namely the first motor 19, is installed outside the first power compartment 1, and under the condition that a rotary sealing structure, namely the magnetic fluid sealing device 20 as shown in fig. 1, needs to be provided.

Likewise, for the second power pod 16, reference may be made to the configuration of the first power pod 16.

The existence of two power compartments is equivalent to the addition of a seal, for example, an assembly structure between the first power compartment 1 and the first pipeline 6, the pipeline wall of the first power compartment 1 and the lower end of the first pipeline 6 form a static seal, although the assembly seal problem between the screw rod 3 and the pipeline wall still exists, the whole structure has one more seal, and the whole sealing performance is better.

The same configuration as mentioned in the above paragraph for the first power pod 1 is used for the second power pod 16. In the configuration shown in fig. 2, the motive member of the second power compartment 16, i.e., the second electric motor 17 shown outside the second power compartment 16, is inserted into the second power compartment 16 through the magnetic fluid sealing device 22. Likewise, if adequate heat dissipation is not a concern, the second motor 17 may also be disposed within the second power pod 16, in which case the ferrofluid seal 22 may be omitted.

The nut screw mechanism is used for realizing the linear motion of the supporting rod 7, and it can be understood that the linear motion is one of the most basic motions in the mechanical field, relatively speaking, the transmission precision of the nut screw mechanism is higher, and for the application with slightly lower transmission precision requirement, the nut screw mechanism can be replaced by a hydraulic cylinder, for example, and the hydraulic cylinder can be directly installed in the first power compartment 1 without considering heat dissipation, so that a better sealing effect can be obtained.

In applications where less demanding transmission accuracy is required, it is also possible to use, for example, air cylinders.

Further, while FIG. 2 is a cross-sectional view A-A of FIG. 1, FIG. 2 is not drawn to the same scale as FIG. 1 in order to clearly reflect details. The main body of the structure shown in fig. 2 is a worm gear mechanism, a worm wheel 15 of the worm gear mechanism is fixedly arranged on the key sleeve, and correspondingly, the worm wheel 15 and the supporting rod 7 are coaxial.

The worm 21 of the worm gear mechanism is inserted into the second power compartment 16 through a rotary dynamic seal structure, and the rotary dynamic seal structure is a magnetic fluid seal device 22 shown in fig. 2. For applications where the sealing level is not critical, other rotary sealing structures may be used, such as shaft seals, felt seals, etc.

In some embodiments, a gear drive may also be used, which may be adapted to a bevel gear drive if a gear shaft similar to the worm 21 is in a position perpendicular to the carrier bar 7.

When the gear shaft is parallel to the supporting rod 7, a cylindrical gear can be adopted.

Further, for certain motive components that do not require or require little heat dissipation, such as a hydraulic motor, it may be built into, for example, the second power pod 16.

Claims

1. A vacuum chamber dynamic seal drive assembly, comprising:

2. The vacuum chamber dynamic seal drive assembly of claim 1, wherein the linear drive section comprises a first power pod forming a first seal with the pipe support.

3. The vacuum chamber dynamic seal drive assembly according to claim 2, wherein the linear drive section comprises a lead screw having one end mounted to the first power compartment via a third bearing and a nut mounted to the pallet and forming a nut-lead screw mechanism with the lead screw;

4. The vacuum chamber dynamic seal drive assembly of claim 3, wherein there are two lead screws, and the two lead screws are symmetrical about the axis of the carrier rod.

5. The vacuum chamber dynamic seal drive assembly of claim 4, wherein the first bearing is a universal joint bearing.

6. The vacuum chamber dynamic seal drive assembly of claim 2 ~ 5, wherein the linear drive section has a motive member mounted outside the first power compartment, the motive member and the first power compartment being mounted to the first power compartment by magnetic fluid sealing means.

7. The vacuum chamber dynamic seal drive assembly of claim 1, wherein the key sleeve is a splined sleeve or a flat key sleeve.

8. The vacuum chamber dynamic seal drive assembly of claim 1, wherein the rotational drive section is located in a middle portion of the pipe rack and comprises a second power pod;

9. The vacuum chamber dynamic seal drive assembly of claim 8, wherein the rotary drive section comprises:

a driven member fixedly mounted on the key sleeve;

10. The vacuum chamber dynamic seal drive assembly of claim 9, wherein the driven member is a turbine or a driven bevel gear;