A flexible constant force pressing mechanism

Abstract

The present invention relates to a fragile component pressing structure and discloses a compliant constant-force pressing mechanism, comprising a stage for carrying components, a base fixedly connected to the stage, a compliant mechanism vertically slidably connected to the base, a contact base hinged to the compliant mechanism, and a contact fixedly connected to the contact base and used for pressing the components; the compliant mechanism can at least move downward from point A to point B, so that the contact presses the component at point A, and during the movement of the compliant mechanism from point A to point B, the pressure of the contact on the component remains unchanged; when fixing or pre-tightening fragile optical components, it can effectively ensure that the contact force between the contact and the component will not change within a small range, thereby achieving the purpose of protecting the fragile components and eliminating the influence of some thermal stress and assembly stress on the components.

Description

Technical Field

[0001] The invention relates to the field of fragile element pressing structures, and in particular to a compliant constant force pressing mechanism. Background Art

[0002] In the field of optical precision mechanics, the structural form can largely determine the measurement accuracy. Minor deformation of optical components will have a great impact on the optical path, especially when there are large changes in contact stress and temperature difference.

[0003] In the field of optical precision machinery, fragile optical components are fixed by gluing or supported by gaskets made of elastic materials, but the above fixing schemes have the following problems: First, they are not easy to disassemble and replace; second, during the locking process, the elastic gasket will deform, which will also increase pressure on the surface of the component and change the accuracy of the component; third, thermal stress and assembly stress also have adverse effects on optical components.

[0004] The present invention proposes a flexible constant force clamping mechanism, which can not only solve the problem of excessive contact stress or deformation during pre-tightening, but also reduce the adverse effects caused by the deformation of structural parts with different thermal expansion coefficients when there is a large temperature difference. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a flexible constant force pressing mechanism.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0007] A compliant constant-force pressing mechanism comprises a stage for carrying components, a base fixedly connected to the stage, at least one pair of compliant mechanisms vertically slidably connected to the base, a contact base hinged to the compliant mechanism, and a contact fixedly connected to the contact base and used for pressing the components; the compliant mechanism can at least move downward from point A to point B, so that the contact presses the component at point A, and during the movement of the compliant mechanism from point A to point B, the pressure of the contact on the component remains unchanged.

[0008] Furthermore, it includes a groove formed on the inner wall of the base, a push rod fixedly connected to the compliance mechanism and slidably matched with the groove, a blind hole formed at the lower end of the push rod, and a reset spring vertically placed in the blind hole.

[0009] Furthermore, it includes a synchronous displacement ring threadedly connected to the outer surface of the base; the upper end of the synchronous displacement ring has a flange extending radially inward, and when the synchronous displacement ring is rotated to move downward relative to the base, the flange is pressed and contacted with the upper ends of the two push rods.

[0010] Furthermore, the compliant mechanism includes a vertically arranged rectangular beam, a cantilever beam fixedly connected to the rectangular beam at one end and hinged to the base at the other end; the cantilever beam forms a non-zero angle with the horizontal plane, the thickness of the rectangular beam is not more than 1 mm, and the material includes titanium alloy.

[0011] Compared with the prior art, the beneficial technical effects of the present invention are:

[0012] The compliant mechanism and the base in the present invention are hinged to form a compliant constant force unit. When fixing or pre-tightening fragile optical components, it can effectively ensure that the contact force between the contacts and the components will not change within a small range, thereby achieving the purpose of protecting fragile components; the compliant constant force unit can eliminate the influence of some thermal stress and assembly stress on the components through its own geometric structure.

[0013] The compression and relaxation are achieved by rotating the synchronous displacement ring. The synchronous displacement ring, push rod and flexible constant force can be disassembled quickly, making it easy to install and remove components. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 An exploded view of the present invention as a whole;

[0015] Figure 2 It is a structural schematic diagram of the synchronous displacement ring of the present invention;

[0016] Figure 3 It is a schematic diagram of the structure of the contact of the present invention;

[0017] Figure 4 It is a structural schematic diagram of the flexible constant force unit of the present invention. DETAILED DESCRIPTION

[0018] A preferred embodiment of the present invention is described in detail below with reference to the accompanying drawings.

[0019] like Figure 1 , 2 As shown in , 3 and 4, a flexible constant force clamping mechanism includes a base 3, a stage 1, a flexible mechanism 5, a contact base 4, a contact 41, a pin 42, a push rod 6, a synchronous displacement ring 7, a reset spring 61 and a mounting screw.

[0020] The stage 1 is installed at the bottom of the base 3 and locked with mounting screws; there is an opening at the center of the stage 1 for accommodating the optical path.

[0021] The contact 41 is made of a material with high stiffness and high friction coefficient, with a thread on one end and a hemispherical end on the other end. The hemispherical contact is in normal point-to-surface contact with the pressed component. Compared with the traditional surface-to-surface contact, the contact area is reduced, which can better reduce the influence of thermal stress and assembly stress on device deformation. The contact base 4 is provided with threaded holes and pin holes, and the contact 41 is rotated and installed in the threaded hole of the contact base 4. The contact base 4 is installed on two symmetrically arranged compliant mechanisms 5 through the cooperation of the pin shaft 42 and the pin hole to form a compliant constant force unit.

[0022] A push rod 6 is installed on the side of the compliance mechanism 5. A blind hole is provided at the tail of the push rod 6 for installing a return spring 61. The lower end of the return spring presses against the base.

[0023] The outer surface of the base 3 is an arc surface, on which a precision fine pitch thread matching the inner wall of the synchronous displacement ring 7 is processed. The inner wall of the base 3 is provided with a groove 31 extending in the vertical direction, and the push rod 6 can slide smoothly up and down along the groove 31.

[0024] The upper end of the synchronous displacement ring 7 has a flange 71 extending radially inward. After the synchronous displacement ring 7 is screwed onto the base 3, the flange 71 presses the upper surface of the push rod 6. The synchronous displacement ring 7 continues to rotate, which can drive the push rods 6 and the flexible mechanism 5 on both sides to move downward synchronously.

[0025] When the synchronous displacement ring 7 rotates and moves upward, the push rod 6 moves to the original position under the elastic force of the reset spring 61; the synchronous displacement ring 7 is rotated and removed from the base 3, the push rod 6 and the flexible constant force unit can be quickly removed, and the component 2 can be taken out, thereby realizing the rapid installation and disassembly of the component 2 without bonding.

[0026] The compliant mechanism 5 is composed of a vertically arranged rectangular thin-walled beam 51 and a cantilever beam 52 that is inclined at a certain angle to the horizontal plane; the compliant mechanism 5 should be made of titanium alloy or a material with better comprehensive mechanical properties, and processed by wire cutting. The material thickness is not more than 1mm, and there are transition fillets at each corner to eliminate stress concentration. The structure of the above-mentioned compliant mechanism 5 can achieve constant force output within a certain displacement range, and different constant force outputs can be achieved by adjusting the structural geometric parameters of the compliant mechanism 5, which can be achieved specifically through a pseudo-rigid body model and a stiffness combination method.

[0027] Place the fragile component 2 on the stage 1, rotate the synchronous displacement ring 7, the contact 41 contacts the surface of the component 2, and continue to adjust the screw-in displacement to achieve constant force compression within a certain displacement range.

[0028] The contact base 4 is also provided with a light-transmitting hole and a weight-reducing hole.

[0029] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention, and any reference numerals in the claims should not be regarded as limiting the claims involved.

[0030] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A flexible constant force pressing mechanism, characterized in that: It includes a stage for carrying components, a base fixedly connected to the stage, at least one pair of compliant mechanisms vertically slidably connected to the base, a contact base hinged to the compliant mechanism, and a contact fixedly connected to the contact base and used for pressing the components; the compliant mechanism can at least move downward from point A to point B, so that the contact presses the component at point A, and during the movement of the compliant mechanism from point A to point B, the pressure of the contact on the component remains unchanged; It includes a groove formed on the inner wall of the base, a push rod fixedly connected to the compliance mechanism and slidingly matched with the groove, a blind hole formed at the lower end of the push rod, and a reset spring vertically placed in the blind hole; It comprises a synchronous displacement ring threadedly connected to the outer surface of the base; the upper end of the synchronous displacement ring has a flange extending radially inward, and when the synchronous displacement ring is rotated to make the synchronous displacement ring move downward relative to the base, the flange is pressed and contacted with the upper ends of the two push rods; the pressing and loosening of the push rods, as well as the disassembly of the synchronous displacement ring, the push rods and the flexible constant force are achieved by rotating the synchronous displacement ring: after the synchronous displacement ring is screwed on the base, the flange presses the upper surface of the push rod, and the synchronous displacement ring continues to rotate, which can drive the push rods and the flexible mechanism on both sides to move downward synchronously; when the synchronous displacement ring rotates and moves upward, the push rod moves to the original position under the elastic force of the reset spring; the synchronous displacement ring is rotated and removed from the base, so that the push rod and the flexible constant force unit can be removed; The compliant mechanism includes a vertically arranged rectangular beam, a cantilever beam fixedly connected to the rectangular beam at one end and hinged to the base at the other end; the cantilever beam forms a non-zero angle with the horizontal plane, the thickness of the rectangular beam is not more than 1mm, and the material includes titanium alloy.

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