Small-size high-vacuum two-dimensional linear manipulator and control method

Abstract

The invention belongs to the technical field of vacuum equipment and instruments, and discloses a small-size high-vacuum two-dimensional linear manipulator and a control method. The manipulator comprises a flange base, a rubber ring, a translation disc, an adjusting frame and a spiral micrometer head, the rubber ring is placed in an annular groove of the flange base, the translation disc is fixed through the adjusting frame, and the translation disc is tightly attached to the rubber ring; the upper and lower surfaces of the translation disc are coated with vacuum lubrication sealing grease. During control, the flange base is connected with a vacuum cavity, the translation disc is connected with a controlled object, after vacuum leak detection, the object is adjusted to a target position and locked under the condition that vacuum is not damaged through coarse and fine adjustment of the spiral micrometer head, and lubricating sealing grease is supplemented regularly. Compared with a traditional manipulator, the manipulator is small in size, light in weight and suitable for miniaturized vacuum equipment; the vacuum degree is not influenced by the combination of movement and sealing parts, and the air tightness is good and the translation is normal under 10 <-6 > Pa; parts are simple in structure and low in cost, and a standard flange connector is good in adaptability and convenient to disassemble, assemble and replace.

Description

Technical Field

[0001] The present invention relates to the technical field of vacuum equipment and instruments, and in particular to a small-sized high-vacuum two-dimensional linear manipulator and a control method thereof. Background Art

[0002] Vacuum technology has been widely used in advanced manufacturing and technology fields such as semiconductor device coating, aerospace industry and solid surface science. In vacuum systems, motion introduction components represented by vacuum manipulators can transmit one-dimensional or multi-dimensional motion to the vacuum environment without being affected by cavity isolation, meeting various needs such as sample component transportation, positioning calibration and spatial in-situ measurement.

[0003] Traditional high-vacuum two-dimensional planar manipulators are mainly composed of flange interfaces at both ends and hollow bellows, which will withstand an internal and external pressure difference close to one atmosphere; therefore, the bellows must have a certain axial length to cope with the tensile deformation during movement; the guide rails that control the movement accuracy and stroke will also add additional volume and weight; the above reasons lead to its large axial and radial dimensions, which is not conducive to the overall miniaturization and lightweight of the vacuum system; on the other hand, for application scenarios such as aerodynamic sampling of aerosol mass spectrometers and laser-induced fluorescence spectroscopy observations, there is a need for small spatial adjustments of specific components in a vacuum environment, and at the same time, the weight of the system must not be significantly increased; therefore, a vacuum two-dimensional linear manipulator with compact size and simple structure has become an urgent practical need. Summary of the Invention

[0004] In response to the above problems, the present invention provides a small-sized high-vacuum two-dimensional linear manipulator and a control method. The device mainly includes a flange base, a rubber ring, a translation disk, an adjustment frame, a screw micrometer and other parts; the small-sized high-vacuum two-dimensional linear manipulator tightly fits the moving parts and the sealing parts, and adopts a rubber sealing ring in combination with vacuum lubricating sealing grease to achieve vacuum sealing and motion translation; this structure and connection method ensure that it has the characteristics of vacuum sealing and small size; in addition, four screw micrometers are fixed in pairs on the side of the adjustment frame to adjust the translation amount, realizing its two-dimensional linear high-precision adjustment function.

[0005] In order to solve the above problems, the technical solution adopted by the present invention is:

[0006] A small-sized high-vacuum two-dimensional linear manipulator includes a flange base, a rubber ring, a translation disk that fits the rubber ring, and an adjustment frame sleeved on the outside of the translation disk. The upper and lower sliding translation surfaces of the translation disk are both coated with vacuum lubricating sealing grease, and the vacuum lubricating sealing grease fully infiltrates the gaps between the translation disk and the rubber ring, and between the translation disk and the adjustment frame. The manipulator also includes a drive assembly for adjusting the linear movement of the translation disk. After the vacuum system is evacuated, the translation disk compresses the rubber ring to deform to form an airtight contact surface. Under the lubrication of the vacuum lubricating sealing grease, the drive assembly drives the translation disk to move linearly in a predetermined direction.

[0007] It should be noted that the flange base, rubber ring, translation disk and adjustment frame are connected in sequence; the rubber ring is placed in the annular groove of the flange base, and the adjustment frame fixes the translation disk to the flange base through threaded fasteners. The bottom of the translation disk fits tightly with the rubber ring to form a compact structure; the spiral micrometer heads fixed around the adjustment frame are used to accurately adjust the target position.

[0008] One side of the flange base's vacuum surface is a CF35 knife-edge flange, and the other side has a translation plate limit groove with an annular groove at the bottom for placing a rubber ring; 12 M6 threaded through holes are evenly distributed around the flange base for connecting the vacuum chamber and the adjustment frame.

[0009] The rubber ring is a perfluoroelastomer O-ring, which can operate normally in the temperature range of -25℃ to +327℃ without losing its elasticity and sealing effect. When the vacuum chamber needs to be baked at high temperature to remove residue, the use of perfluoroelastomer O-ring can ensure the sealing effect under high temperature baking conditions, allowing the vacuum system to operate normally during high temperature baking.

[0010] The bottom of the translation plate fits tightly with the sealing ring, and the top is a CF16 blade flange; the contact surface with the spiral micrometer head is 12×15mm 2 The plane,

[0011] Preferably, the sliding translation surface on the upper end of the translation disk is in contact and sliding connection with the lower end surface of the adjustment frame;

[0012] Preferably, the driving assembly includes four screw micrometers, and two adjacent screw micrometers are perpendicular to each other between horizontal planes.

[0013] Preferably, the micrometer screw is detachably connected to the adjustment frame, and a side wall of the adjustment frame is provided with an opening for the micrometer screw to pass through.

[0014] The bottom of the adjustment mount fits snugly against the translation plate, and six 6.5mm through-holes are evenly spaced around the bottom panel, with the same radius as the six M6 threaded holes on the flange base. Four alignment holes are also located around the adjustment mount for mounting micrometer screws.

[0015] The end face of the screw micrometer is flat and fits tightly with the translation disk during adjustment operation.

[0016] The threaded fasteners are 16mm long M6 screws.

[0017] Preferably, the filled vacuum lubricating sealing grease can significantly reduce the radial sliding friction of the relative moving surfaces. It has appropriate viscosity, high and low temperature resistance and low vacuum degassing rate. The working temperature is -40 to 204°C. At 200°C, the precipitation is less than 0.5% in 24 hours and the evaporation is less than 2%. It overcomes the problem of "large degassing volume makes it difficult to maintain vacuum degree" of traditional materials in high temperature environment. Even at temperatures close to the thermal limit of the material, the gas release volume can still be controlled at an extremely low level to ensure the vacuum degree of high vacuum equipment; it is insoluble in water, methanol, ethanol, acetone, ethylene glycol and glycerin, and can be dispersed with kerosene, benzene, toluene or ether, etc., which can significantly reduce the radial sliding friction of the relative moving surfaces.

[0018] Finally, it should be noted that the contact surface between the translation disk and the screw micrometer must be flat, and the size of the translation disk should be designed and adjusted according to the needs; the function of the adjustment frame is to limit the sliding and fix the translation disk and the screw micrometer at the same time; to avoid the translation disk being subjected to torque during the adjustment process, which may cause the seal to deteriorate.

[0019] A small-size high-vacuum two-dimensional linear manipulation method uses the above-mentioned small-size high-vacuum two-dimensional linear manipulator, comprising the following steps: Step 1, connecting the flange base to the vacuum chamber, and connecting the translation disk to the manipulated object; before connection, using vacuum lubricating sealing grease to fully infiltrate the gaps between the translation disk and the rubber ring, and between the translation disk and the adjustment frame; after connection, performing vacuum leak detection to ensure the vacuum degree of the vacuum chamber; Step 2, controlling the adjustment of the manipulated object in two dimensions through a drive component; adjusting the manipulated object to a target position without destroying the vacuum; Step 3, regularly replenishing the vacuum lubricating sealing grease.

[0020] Preferably, the driving assembly realizes the adjustment of the manipulated object in two dimensions by manipulating four screw micrometers, and the aligned screw micrometers perform coarse adjustment at equal intervals of 0.5 mm and fine adjustment at equal intervals of 0.01 mm.

[0021] It should be noted that the translation disk here extends in a direction perpendicular to the flange base and has a certain thickness. The telescopic ends of the four screw micrometers need to be located close to the translation disk to align and realize drive control.

[0022] The drive control through the above-mentioned structural design can prevent the spiral micrometer head from generating excessive torque to squeeze the rubber ring at the lower end during the process of driving the translation disk, thereby avoiding failure of the rubber ring due to excessive pressure, extending the service life of the rubber ring and improving the sealing effect.

[0023] Setting a coarse adjustment size of 0.5 mm can achieve a balance between fast positioning and controllable errors; the 0.01 mm step size is close to the accuracy limit of traditional mechanical transmission (the repeatability accuracy of ball screws is usually 5-10 microns), and can also avoid the influence of static friction fluctuations between transmission components under small displacements caused by too small a step size.

[0024] Preferably, the opposed micrometer screws are tightened to a preset torque (1.2±0.1 N·m), and the translation disk is locked in the target position by the stress balance principle to avoid displacement drift caused by vacuum pressure difference.

[0025] Setting this torque can form a torsional resistance torque between the thread pairs, which can effectively resist the low-frequency vibration generated during equipment operation. In addition, this torque does not reach the yield strength of the material, which can prevent plastic deformation of the screw while ensuring the tightening effect, ensuring the safety of the spiral micrometer structure.

[0026] Preferably, when replenishing vacuum lubricating sealing grease, add 10 μL of vacuum lubricating sealing grease in sequence at four locations evenly distributed around the translation disk, and slowly rotate the translation disk 360° to evenly spread the vacuum lubricating sealing grease around the translation disk, ensuring that the sealing grease forms a uniform molecular film on the contact surface.

[0027] Preferably, vacuum lubricating sealing grease should be replenished every 200 hours of operation. After the vacuum lubricating sealing grease has been running in a vacuum environment for 200 hours, the volatilization of the base oil can reach about 15% of the initial mass, resulting in a sudden increase in the viscosity of the grease, a decrease in the thickness of the synovial film, and an increase in the friction coefficient. Therefore, 200 hours of operation is the preferred time to replenish vacuum lubricating sealing grease.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] 1. The present invention has a small volume and light weight, has important application value in miniaturized and lightweight vacuum equipment, and can meet the requirements of two-dimensional linear motion introduction.

[0030] 2. The combination of moving parts and sealing parts will not affect the vacuum degree of the system. The measured results show that the present invention has a vacuum degree of 10 -6 Pa, it not only has good airtightness, but also the translational movement can be carried out normally.

[0031] 3. The components that make up the system have a simple structure and low cost. The standard vacuum flange interfaces at both ends have good adaptability, making it easy to quickly disassemble or replace components at the application site. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a structural schematic diagram of the present invention.

[0033] Figure 2It is a schematic top view of the present invention.

[0034] Figure 3 It is a cross-sectional schematic diagram of the present invention.

[0035] Figure 4 It is a schematic diagram of the front view of the present invention.

[0036] Figure 5 It is a bottom view schematic diagram of the present invention.

[0037] Figure 6 It is a left side view schematic diagram of the present invention.

[0038] Figure 7 It is an isometric view schematic diagram of the present invention.

[0039] The flange used for vacuum system connection in the figure uses a CF blade, but this interface type is not a specific limitation of the present invention. Substitution of other vacuum connection types that comply with current standards also falls within the scope of protection of the present invention. The other specific details described below are only intended to provide a full understanding of the present invention. Obviously, the present invention can also be implemented in other ways than those described. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0040] In the figure: 1. Flange base; 2. Rubber ring; 3. Translation plate; 4. Adjustment bracket; 5. Micrometer screw; 6. Threaded fastener. DETAILED DESCRIPTION

[0041] The present invention will be further described below with reference to the accompanying drawings and examples.

[0042] Refer to the attached Figure 1-7 In the schematic diagram of a small-size high-vacuum two-dimensional linear manipulator based on sliding seals, the sliding displacement is achieved by the translation disk 3 driving other vacuum components installed on it; the sliding is restricted by the screw micrometer heads 5 fixed around the adjustment frame 4 and can only be carried out along two mutually perpendicular directions in the plane; depending on the selection of the flange base 1, the stroke in each direction can be adjusted to 5 to 10 mm.

[0043] The adjustment frame 4 is mounted on the flange base 1 by four hexagon socket screws 6, and downward pressure is applied to keep the translation plate 3, rubber ring 2 and flange base 1 in close contact in sequence; since the upper and lower surfaces of the translation plate 3 are pre-coated with vacuum lubricating sealing grease, the surface friction coefficient between the contact surfaces is effectively reduced, and the obstruction of the above-mentioned translation caused by the pressure difference between the inside and outside of the vacuum system and the surface wear of the rubber ring 2 are reduced to a minimum, and the movement of the translation plate 3 will not destroy the airtightness of the vacuum system; the measured results show that the present invention can maintain a high degree of stability within 10 to 200 degrees. -6 The motion introduction in the vacuum system can still be successfully completed under the high vacuum conditions of Pa.

[0044] Taking into account the material strength and manufacturing process cost, all the above components except the micrometer are made of 304 stainless steel; for components with relative motion, the arithmetic mean deviation of the surface roughness is R a It should be less than 1.6μm; the flange cutting edges of the flange base 1 and the ends of the translation disk 3 are respectively processed for the purpose of illustration. CF35 and CF16 flange cutting edges are preferably used here, and their characteristic dimensions are given by the ISO 3669:2020 standard; it is also necessary to evenly distribute a number of threaded holes or through holes of corresponding sizes around the flange base 1 for the overall assembly of the vacuum manipulator.

[0045] After processing and assembly according to the above scheme, a small-sized high-vacuum two-dimensional linear manipulator proposed by the present invention can be obtained; the flange base 1 is installed on the vacuum chamber, and the vacuum parts that need to be moved and adjusted, such as capillaries, aerodynamic lenses, temperature sensors or optical lenses, are installed at the end of the translation disk 3; by slowly turning the two opposing screw micrometers in the same direction, the translation disk 3 can be slid in a certain direction to adjust the spatial position of the corresponding parts; after the adjustment is in place, the screw micrometer on the "relaxed" side is called back to clamp the translation disk; similarly, the displacement in the other direction can be adjusted to realize the introduction of limited stroke movement in the two-dimensional plane of the vacuum system.

[0046] It should be noted that:

[0047] The small-sized, high-vacuum, two-dimensional linear manipulator proposed in this invention tightly fits the moving parts and the sealing parts, and uses a rubber sealing ring in conjunction with vacuum lubricating sealing grease to achieve vacuum sealing and motion translation. The invention mainly comprises a flange base, a rubber ring, a translation disk, an adjustment frame, and a micrometer screw. The rubber ring is placed in an annular groove of the flange base, and the normal force deformation caused by the vacuum pressure difference causes the flange base, the rubber ring, the translation disk, and the adjustment frame to form direct contact with each other in turn. The upper and lower surfaces of the translation disk are evenly coated with vacuum lubricating sealing grease that is not easily volatile and deteriorates, ensuring airtightness while allowing the translation disk to slide smoothly on the contact surface. The adjustment frame is connected to the top of the flange base by four screws to provide initial downward force for the translation disk. Four micrometer screws are fixed to the sides of the adjustment frame in pairs for manual adjustment of the translation amount.

[0048] A further solution is that the flange base and the end of the translation plate are provided with vacuum flange interfaces that comply with current general standards, so as to facilitate installation of other vacuum components as needed.

[0049] A further solution is to ensure airtightness between the flange base and the translation disk by the force deformation of the rubber ring; evenly apply vacuum lubricating sealing grease on the bottom surface of the translation disk to reduce the sliding friction of the contact surface, so that it can freely translate within a certain range relative to the rubber ring.

[0050] A further solution is that the upper surface of the translation disk is in direct contact with the adjustment frame, and the contact surface is also evenly coated with vacuum lubricating sealing grease. The adjustment frame applies initial downward pressure and ensures that the movement of the translation disk is not hindered by friction.

[0051] A further solution is that a micrometer screw is fixed to the side of the adjustment frame by a thread, and the top of the micrometer screw is in contact with the translation disk. The micrometer screw restricts the planar sliding of the translation disk to only two mutually perpendicular directions in the plane.

[0052] A further solution is that the vacuum lubricating sealing grease used in the present invention has appropriate viscosity, high and low temperature resistance and low vacuum outgassing rate, which can significantly reduce the radial sliding friction of the relative moving surfaces; -7 Pa is used in a high vacuum environment, and its evaporation and adsorption effects on the vacuum system can be ignored.

[0053] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A small-sized high-vacuum two-dimensional linear manipulator, comprising a flange base (1), a rubber ring (2), a translation disk (3) fitted with the rubber ring (2), and an adjustment frame (4) sleeved on the outside of the translation disk (3), characterized in that: The upper and lower sliding surfaces of the translation disk (3) are both coated with vacuum lubricating sealing grease, and the gaps between the translation disk (3) and the rubber ring (2), and between the translation disk (3) and the adjustment frame (4) are fully infiltrated by the vacuum lubricating sealing grease, and a driving component for adjusting the linear movement of the translation disk (3) is also included; After the vacuum system is evacuated, the translation disk (3) compresses the rubber ring (2) to deform and form an airtight contact surface. Under the lubrication of the vacuum lubricating sealing grease, the driving component drives the translation disk (3) to move linearly in a predetermined direction.

2. The small-sized high-vacuum two-dimensional linear manipulator according to claim 1, characterized in that: The upper end sliding translation surface of the translation disk (3) is in contact and sliding connection with the lower end surface of the adjustment frame (4).

3. The small-sized high-vacuum two-dimensional linear manipulator according to claim 1, characterized in that: The driving assembly comprises four spiral micrometers (5), and two adjacent spiral micrometers (5) are perpendicular to each other between horizontal planes.

4. The small-sized high-vacuum two-dimensional linear manipulator according to claim 3, characterized in that: The micrometer screw (5) is detachably connected to the adjustment frame (4), and a side wall of the adjustment frame (4) is provided with an opening for the micrometer screw (5) to pass through.

5. The small-sized high-vacuum two-dimensional linear manipulator according to claim 1, characterized in that: The filled vacuum lubricating sealing grease has appropriate viscosity, high and low temperature resistance and low vacuum outgassing rate. The working temperature is -40 ~ 204 ℃. At 200 ℃, the precipitation in 24 hours is less than 0.5% and the evaporation is less than 2%; it is insoluble in water, methanol, ethanol, acetone, ethylene glycol and glycerin, and can be dispersed with kerosene, benzene, toluene or ether.

6. A small-scale high-vacuum two-dimensional linear manipulation method, characterized in that: Using the small-size high-vacuum two-dimensional linear manipulator according to any one of claims 1 to 5 comprises the following steps: Step 1: Connect the flange base 1 to the vacuum chamber, and connect the translation disk 3 to the manipulated object; before connecting, use vacuum lubricating sealing grease to fully wet the gaps between the translation disk (3) and the rubber ring (2), and between the translation disk (3) and the adjustment frame (4); after connecting, perform vacuum leak detection to ensure the vacuum degree of the vacuum chamber; Step 2: Control the manipulation of the object in two dimensions by the drive assembly; adjust the manipulated object to the target position without breaking the vacuum; Step 3: Regularly add vacuum lubrication and sealing grease.

7. The small-scale high-vacuum two-dimensional linear manipulation method according to claim 6, characterized in that: The driving assembly realizes the adjustment of the manipulated object in two dimensions by manipulating four screw micrometers (5), and the aligned screw micrometers (5) are coarsely adjusted in 0.5 mm steps and finely adjusted in 0.01 mm steps.

8. The small-scale high-vacuum two-dimensional linear manipulation method according to claim 7, characterized in that: Tighten the opposed micrometer screws to the preset torque of 1.2±0.1N·m. The translation disk is locked in the target position through the stress balance principle to avoid displacement drift caused by vacuum pressure difference.

9. The small-scale high-vacuum two-dimensional linear manipulation method according to claim 6, characterized in that: When replenishing vacuum lubricating sealing grease, add 10 μL of vacuum lubricating sealing grease to four locations evenly distributed around the translation disk, and slowly rotate the translation disk 360° to ensure that the sealing grease forms a uniform molecular film on the contact surface.

10. The small-scale high-vacuum two-dimensional linear manipulation method according to claim 6, characterized in that: Replenish vacuum lubrication and sealing grease every 200 hours of operation.

Images