High-precision rapid adjustment diaphragm mechanism

Abstract

The invention discloses a high-precision rapid adjustment diaphragm mechanism, and solves the technical problems that a motor backlash phenomenon exists during reciprocating change of a diaphragm due to a meshing gap in gear meshing transmission in the prior art, steel belt transmission has great difficulty in subsequent maintenance, and the force transmission path of a system is increased by both the gear meshing transmission and the steel belt transmission. Comprising a direct-current torque motor, a hollow light-passing main shaft, a mounting bracket, a rolling bearing and an encoder, the light-passing main shaft is directly driven by the direct-current torque motor to drive a diaphragm disc surface of a diaphragm to rotate, and the opening size of a diaphragm light-passing hole is adjusted. External gear meshing transmission and an internal motor speed reducing mechanism are omitted, the influence of gear backlash on the reciprocating rotation precision of the diaphragm during gear meshing is reduced, the rotation precision of the system is improved, a certain gap exists between the motor stator and the motor rotor of the direct-current torque motor, no mechanical friction part exists in the operation process, and the reliability of the system is improved. And the maintenance cost is reduced, and meanwhile, the vibration phenomenon of the system during working is reduced.

Description

Technical Field

[0001] The invention relates to an aperture mechanism, and in particular to a high-precision and fast-adjusting aperture mechanism. Background Art

[0002] In recent years, with the development of analog optoelectronic product technology, there have been more requirements for the types of simulated targets of simulation equipment. Some simulation equipment that simulates the motion posture of the target requires the aperture adjustment mechanism to have high precision, fast response and small reciprocating rotation error.

[0003] Chinese invention patent CN117406315B discloses a small, compact electric iris diaphragm, comprising an iris assembly, including an iris seat. A cover plate is embedded and fixed to the front of the iris seat, and a large iris gear is rotatably connected to the inner side of the cover plate. The upper end of the large iris gear is meshed with a drive gear. The center of the drive gear is fixedly connected to the light-entering end of a servo, which is fixedly connected to the outer side of the cover plate. This invention uses a servo as the drive and the drive gear as the transmission. By controlling the servo's rotation angle, the position of the large iris gear is controlled to adjust the aperture size. However, due to the meshing backlash in the gears, the motor experiences backlash during the reciprocating movement of the iris, resulting in poor system accuracy.

[0004] Chinese invention patent CN118464182B discloses a high-precision aperture adjustment mechanism, comprising a driving pulley, two driven pulleys, a housing, a steel belt, an aperture, a drive motor, and a tensioning pulley. The motor drives the driving pulley, which is then transmitted to the two driven pulleys by a steel belt. A tensioning pulley is located within the housing to tighten the steel belt during movement, ensuring accurate belt transmission. A circular aperture is defined in the housing, with two apertures positioned on either side. The two apertures are mounted on the housing and designed with two guide rails. The steel belt drives the two apertures, allowing them to move vertically in opposite directions. Adjusting the rotation angle of the drive motor changes the light-passing area, enabling adjustment of the aperture aperture. The addition of a tensioning pulley to tension the steel belt eliminates backlash and improves system accuracy. However, the steel belt transmission requires the belt to remain taut at all times, making subsequent maintenance difficult.

[0005] Both gear meshing and steel belt transmission increase the system's force transmission path. This increased force transmission path affects both the control and response of the aperture size. Because gear meshing and steel belt drive methods require the placement of a drive motor, they require significant radial space and an irregular spatial envelope, limiting their application scope. Summary of the Invention

[0006] The purpose of the present invention is to solve the problems in the prior art of meshing clearance in the gear meshing transmission, which leads to motor backlash when the aperture changes back and forth, and the difficulty of subsequent maintenance due to the steel belt transmission, as well as the fact that both increase the system's force transmission path, and to provide a high-precision and fast-adjustable aperture mechanism.

[0007] To achieve the above object, the technical solution adopted by the present invention is:

[0008] A high-precision, fast-adjusting diaphragm mechanism includes a Guanlan; the special feature of the mechanism is that it includes a DC torque motor, a hollow light-transmitting spindle and a mounting bracket, a rolling bearing, and an encoder;

[0009] The DC torque motor includes a motor stator and a motor rotor. One end of the motor rotor has a top wall and the other end is an open hollow structure. The top wall has a through hole. The motor rotor is sleeved on the light-emitting end of the light-transmitting main shaft through the hollow structure, and the two are fixedly connected. The outer wall surface of the top wall is detachably connected to the viewing disk surface of the iris. The maximum aperture of the iris light-transmitting hole is less than or equal to the aperture of the through hole. The motor stator is fixedly connected to the mounting bracket, and the mounting bracket is fixedly connected to the iris lever of the iris.

[0010] The inner ring of the rolling bearing is sleeved on the light-transmitting main shaft, and the two are interference fit; the upper end face of the inner ring of the rolling bearing abuts against the end face of the open end of the motor rotor, the upper end face of the outer ring of the rolling bearing abuts against the end face of one end of the motor stator, and the outer ring of the rolling bearing is nested on the inner wall surface of the mounting bracket, and the two are interference fit;

[0011] The encoder includes an encoder rotor and an encoder stator. The encoder rotor and the encoder inner shaft fixing pressure ring are sequentially sleeved on the outer peripheral wall of the light incident end of the light-transmitting main shaft. One end of the encoder rotor abuts against the lower end surface of the inner ring of the rolling bearing, and the other end is axially limited by being threadedly connected to the encoder inner shaft fixing pressure ring with the light-transmitting main shaft. The encoder stator is fixedly connected to the mounting bracket.

[0012] Furthermore, the mounting bracket has a limiting boss extending radially inward at one end thereof close to the rolling bearing, and the lower end surface of the outer ring of the rolling bearing abuts against the inner wall surface of the limiting boss;

[0013] An annular boss is provided on the outer peripheral wall of the light-transmitting main shaft. The side of the annular boss close to the motor rotor is the first limiting surface, and the opposite surface is the second limiting surface. The end face of the motor rotor abuts against the first limiting surface, and the upper end face of the inner ring of the rolling bearing abuts against the second limiting surface.

[0014] Furthermore, the inner diameter of the end of the light-transmitting main shaft close to the encoder is defined as R1, the inner diameter of the end close to the motor rotor is defined as R2, and the maximum aperture of the aperture light-transmitting hole is defined as R5. Then, R1, R2, and R5 satisfy the condition: R5≤R2<R1.

[0015] Furthermore, a rolling bearing outer retaining ring is provided between the motor stator and the outer ring of the rolling bearing. The outer diameter of the rolling bearing outer retaining ring is adapted to the size of the motor stator outer ring. Definition: the inner diameter of the rolling bearing outer retaining ring is R3, and the inner diameter of the rolling bearing outer ring is R4, then R3≤R4.

[0016] Furthermore, a rolling bearing inner retaining ring is provided between the inner ring of the rolling bearing and the rotor of the encoder, and the rolling bearing inner retaining ring is sleeved on the outer peripheral wall of the light-transmitting main shaft.

[0017] Furthermore, an encoder inner shaft mounting gasket is provided between the inner retaining ring of the rolling bearing and the rotor of the encoder, and the encoder inner shaft mounting gasket is sleeved on the outer peripheral wall of the light-transmitting main shaft.

[0018] Furthermore, the encoder inner shaft mounting gasket is a copper gasket, and the thickness of the copper gasket ranges from 0.4 mm to 0.6 mm.

[0019] Furthermore, the aperture is a fully closable aperture.

[0020] Furthermore, a lever gasket is provided between the aperture lever and the mounting bracket.

[0021] Furthermore, a mounting protrusion is provided on the circumferential outer wall of the mounting bracket near one end of the encoder stator, and at least two mounting holes are provided along the circumference of the mounting protrusion. An encoder mounting block is provided on the outer circumferential wall of the encoder stator. The encoder mounting block is provided in one-to-one correspondence with the mounting hole, and the two are connected by bolts.

[0022] Compared with the prior art, the present invention has the following beneficial technical effects:

[0023] 1. This invention provides a high-precision, fast-adjustable aperture mechanism that utilizes a DC torque motor to directly drive the aperture spindle, driving the aperture disk to adjust the aperture opening size. This eliminates the need for external gear meshing and internal motor reduction mechanisms, minimizing the impact of gear meshing backlash on the aperture's reciprocating rotation accuracy and improving system rotation accuracy. The DC torque motor's stator and rotor provide a clearance, eliminating mechanical friction components during operation, reducing maintenance costs and minimizing vibration during system operation.

[0024] 2. This invention provides a high-precision, rapid aperture adjustment mechanism that utilizes a light-transmitting spindle in conjunction with an encoder. The encoder utilizes a separate, contactless design, consisting of a rotor and stator, enabling real-time monitoring of the aperture position. Direct motor drive reduces the system's power transmission path, significantly improving system response sensitivity.

[0025] 3. The present invention provides a high-precision, fast-adjustable aperture mechanism that highly integrates components such as a DC torque motor, an encoder, and a fully closable aperture. The overall outer envelope of the system is relatively regular. Since it is driven by a DC torque motor, the radial position deviation caused by gear meshing is reduced, and a modular design can be implemented.

[0026] 4. The present invention provides a high-precision, fast-adjustable iris mechanism, which detachably connects the iris to the end face of the motor rotor, making it easy to replace irises with different opening and closing apertures, thereby realizing a fast control mechanism for different aperture requirements.

[0027] 5. The present invention provides a high-precision, fast-adjustable diaphragm mechanism with a regular overall outer envelope. It can be added to various overall systems as a modular design, and has a wider range of adaptability. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a schematic structural diagram of an embodiment of a high-precision, fast-adjustable aperture mechanism according to the present invention;

[0029] Figure 2 A top view of an embodiment of the present invention;

[0030] Figure 3 An exploded view of an embodiment of a high-precision, fast-adjustable aperture mechanism according to the present invention;

[0031] Figure 4 This is an axial cross-sectional view of an embodiment of a high-precision, fast-adjustable aperture mechanism of the present invention.

[0032] The following are the descriptions of the reference numerals:

[0033] 1. Mounting bracket; 2. Motor rotor; 3. Motor stator; 4. Aperture; 5. Lever gasket; 6. Encoder; 7. Encoder mounting block; 8. Light-transmitting spindle; 9. Rolling bearing outer retaining ring; 10. Rolling bearing; 11. Encoder inner shaft fixing pressure ring; 12. Rolling bearing inner retaining ring. DETAILED DESCRIPTION

[0034] In order to make the purpose, advantages and features of the present invention more clear, the high-precision fast adjustment aperture mechanism proposed by the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0035] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0036] like Figure 1-4 As shown, in order to achieve high-precision and rapid adjustment of the aperture, and the outer envelope of the aperture is regular, the present invention designs a high-precision and rapid adjustment aperture mechanism, which includes a DC torque motor, a hollow light-transmitting main shaft 8, a hollow mounting bracket 1, a rolling bearing 10, a rolling bearing outer retaining ring 9, a rolling bearing inner retaining ring 12, a fully closable aperture (i.e., aperture 4), an encoder 6, an encoder inner shaft fixing pressure ring 11, and an encoder mounting block 7. The DC torque motor includes a motor rotor 2 and a motor stator 3. The connection between the two belongs to the prior art and will not be described in detail here. The encoder includes an encoder rotor and an encoder stator. The connection relationship between the two belongs to the prior art and will not be described in detail here. The fully closable aperture includes an aperture disk and an aperture lever. The connection relationship between the two belongs to the prior art and will not be described in detail here.

[0037] The mounting bracket 1 comprises a circular cylindrical body with a square boss at one end and a mounting protrusion extending radially outward at the other end. A circle of countersunk holes is formed around the end surface of the square boss. One end of the cylindrical body also comprises a position-limiting boss extending radially inward.

[0038] An annular boss is provided on the outer peripheral wall of the light-transmitting main shaft 8 , and the side of the annular boss close to the motor rotor 2 is a first limiting surface, and the opposite side thereof is a second limiting surface.

[0039] The inner ring of rolling bearing 10 is sleeved onto light-transmitting spindle 8 with an interference fit. The upper end face of the inner ring of rolling bearing 10 abuts the second limiting surface. The outer ring of rolling bearing 10 is nested within the inner wall of mounting bracket 1 with an interference fit. The lower end face of the outer ring of rolling bearing 10 abuts the inner wall of the limiting boss. The limiting boss and annular boss limit the axial movement of rolling bearing 10, allowing light-transmitting spindle 8 to rotate smoothly and stably within mounting bracket 1.

[0040] The motor rotor 2 has a top wall at one end and an open hollow structure at the other end. The top wall has a through-hole. The motor rotor 2 is sleeved onto the light-emitting end of the optical spindle 8 through the hollow structure, and the two are fixedly connected by bolts. A fully closable iris is detachably connected to the outer surface of the top wall. Specifically, the iris disk is detachably connected to the outer surface of the top wall, and the iris lever is fixedly connected to the mounting bracket 1. A lever gasket 5 is positioned between the iris lever and the mounting bracket 1. Selecting an appropriate thickness for the lever gasket 5 ensures that the iris lever does not deform after installation and that stress-free deformation occurs during rotation of the iris disk. During system simulation testing, the DC torque motor and encoder 6 must first be debugged using debugging software before installing the fully closable iris to avoid damage during the debugging process. The DC torque motor debugging process includes the current loop, velocity loop, and position loop. The axial position of the encoder rotor is adjusted by adjusting the thickness of the copper gasket. The maximum aperture of the fully closable iris aperture is equal to or smaller than the aperture of the through-hole. Light enters from the light-incoming end of the light-transmitting spindle 8, passes through the through hole on the top wall of the motor rotor 2, and exits from the light-transmitting hole of the fully closed aperture. Definition: The inner diameter of the end of the light-transmitting spindle 8 close to the encoder 6 is R1, and the inner diameter of the end close to the motor rotor is R2. The maximum aperture of the light-transmitting hole of the fully closed aperture is R5, and R1>R2≥R5. Making the aperture of the end of the light-transmitting spindle 8 close to the encoder 6 larger is conducive to the light entering the interior of the light-transmitting spindle. The maximum aperture of the maximum light-transmitting hole of the fully closed aperture is less than or equal to R2, ensuring that a complete optical path is provided for the aperture, and can adapt to more specifications of fully closed apertures, with a miniaturized structure. A DC torque motor is used to directly drive the light-transmitting spindle 8 to drive the aperture disk of the aperture 4 to rotate, so as to adjust the opening size of the light-transmitting hole of the aperture 4. The external gear meshing transmission and the internal motor reduction mechanism are eliminated, which reduces the influence of the tooth side clearance during gear meshing on the reciprocating rotation accuracy of the aperture, and improves the rotation accuracy of the system. There is a certain gap between the motor stator 3 and the motor rotor 2 of the DC torque motor. There are no mechanical friction parts during operation, which reduces maintenance costs and reduces the vibration phenomenon during system operation.

[0041] Before installing the motor stator 3, first place the rolling bearing outer retaining ring 9. One end of the rolling bearing outer retaining ring 9 abuts the upper end face of the outer ring of the rolling bearing 10, and the other end abuts the end face of the motor stator 3. The outer diameter of the rolling bearing outer retaining ring 9 matches the outer ring size of the motor stator 3. Defined as follows: the inner diameter of the rolling bearing outer retaining ring 9 is R3, and the inner diameter of the outer ring of the rolling bearing 10 is R4, then R3 ≤ R4. This dimension ensures that the outer ring of the rolling bearing 10 is firmly fixed, preventing axial movement, making the structure more refined and reducing the dimensional accuracy of the motor stator 3 and the rolling bearing 10. Next, install the motor stator 3 onto the mounting bracket 1. The motor stator 3 is screwed into the threaded hole in the countersunk hole to achieve a fixed connection between the motor stator 3 and the mounting bracket 1. The motor stator 3 is tightly pressed against the rolling bearing 10 by the rolling bearing outer retaining ring 9. This design effectively reduces the axial installation space. Furthermore, during operation, vibrations of the DC torque motor or other components can cause axial movement of the rolling bearing 10, which can cause eccentricity of the light-transmitting spindle 8 and affect the adjustment of the fully closable aperture. The mounting bracket 1 is matched with the mounting outer diameter of the motor stator 3 to ensure that a certain gap is maintained between the motor stator 3 and the motor rotor 2 after installation, allowing the motor rotor 2 to rotate smoothly.

[0042] The outer circumference of the light-entering end of the light-transmitting main shaft 8 is sequentially fitted with a rolling bearing inner retaining ring 12, an encoder inner shaft mounting gasket, and an encoder rotor. Finally, the encoder inner shaft retaining ring 11, threadedly connected to the light-transmitting main shaft 8, provides axial restraint. The rolling bearing inner retaining ring 12 abuts the lower end face of the inner ring of the rolling bearing 10. The rolling bearing outer retaining ring 9, the annular boss, and the limiting boss, along with the rolling bearing inner retaining ring 12, firmly press the rolling bearing 10, limiting its axial movement and ensuring more stable system operation. The encoder inner shaft mounting gasket is a copper gasket with a thickness range of 0.4mm to 0.6mm. When the encoder rotor is mated with the encoder stator, its axial position is sensitive. Due to structural processing errors, the encoder rotor's axial position may not be in the ideal position, necessitating adjustment. This can be achieved by replacing copper gaskets of varying thicknesses to ensure proper encoder 6 operation.

[0043] Three mounting holes are provided along the circumference of the mounting convex ring, and three encoder mounting blocks 7 are provided on the outer peripheral wall of the encoder stator. The encoder mounting blocks 7 are connected to the mounting holes on the mounting convex ring by bolts, and the encoder stator is fixedly connected to the mounting bracket 1 to fix the encoder stator.

[0044] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they may refer to fixed, detachable, or integral connections; mechanical connections; direct connections or indirect connections through an intermediary; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0045] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the present invention.

Claims

1. A high-precision, fast-adjustable diaphragm mechanism, comprising a diaphragm (4); characterized in that: The invention comprises a DC torque motor, a hollow light-transmitting main shaft (8), a mounting bracket (1), a rolling bearing (10) and an encoder (6); the DC torque motor comprises a motor stator (3) and a motor rotor (2); one end of the motor rotor (2) has a top wall, and the other end is an open hollow structure, the top wall has a through hole, the motor rotor (2) is sleeved on the light-emitting end of the light-transmitting main shaft (8) through the hollow structure, and the two are fixedly connected; the outer wall surface of the top wall is detachably connected to the aperture disk surface of the aperture (4); the maximum aperture of the light-transmitting hole of the aperture (4) is less than or equal to the aperture of the through hole; the motor stator (3) is fixedly connected to the mounting bracket (1), and the mounting bracket (1) is fixedly connected to the aperture lever of the aperture (4); The inner ring of the rolling bearing (10) is sleeved on the light-transmitting main shaft (8), and the two are interference-fitted; the upper end face of the outer ring of the rolling bearing (10) abuts against the end face of one end of the motor stator; the outer ring of the rolling bearing (10) is nested on the inner wall surface of the mounting bracket (1), and the two are interference-fitted; The encoder (6) includes an encoder rotor and an encoder stator. The encoder rotor is sleeved on the outer peripheral wall of the light-entering end of the light-transmitting main shaft (8). One end of the encoder rotor abuts against the lower end surface of the inner ring of the rolling bearing (10), and the other end is axially limited by an encoder inner shaft fixing pressure ring (11) threadedly connected to the light-transmitting main shaft (8). The encoder stator is fixedly connected to the mounting bracket (1).

2. The high-precision, fast-adjustable aperture mechanism according to claim 1, characterized in that: The mounting bracket (1) has a limiting boss extending radially inward at one end thereof close to the rolling bearing (10), and the lower end surface of the outer ring of the rolling bearing (10) abuts against the inner wall surface of the limiting boss; An annular boss is provided on the outer peripheral wall of the light-transmitting main shaft (8); the side of the annular boss close to the motor rotor (3) is a first limiting surface, and the opposite surface is a second limiting surface; the end surface of the motor rotor (2) abuts against the first limiting surface, and the upper end surface of the inner ring of the rolling bearing (10) abuts against the second limiting surface.

3. The high-precision, fast-adjustable aperture mechanism according to claim 2, characterized in that: The inner diameter of the end of the light-transmitting main shaft (8) close to the encoder (6) is defined as R1, the inner diameter of the end close to the motor rotor is defined as R2, and the maximum aperture of the light-transmitting hole of the diaphragm (4) is defined as R5. Then, R1, R2, and R5 satisfy the condition: R5≤R2<R1.

4. The high-precision, fast-adjustable aperture mechanism according to claim 3, characterized in that: A rolling bearing outer retaining ring (9) is provided between the motor stator (3) and the outer ring of the rolling bearing (10). The outer diameter of the rolling bearing outer retaining ring (9) is adapted to the outer ring size of the motor stator (3). It is defined that the inner diameter of the rolling bearing outer retaining ring (9) is R3, and the inner diameter of the outer ring of the rolling bearing (10) is R4, then R3≤R4.

5. The high-precision, fast-adjustable aperture mechanism according to claim 4, characterized in that: A rolling bearing inner retaining ring (12) is provided between the inner ring of the rolling bearing (10) and the rotor of the encoder (6), and the rolling bearing inner retaining ring (12) is sleeved on the outer peripheral wall of the light-transmitting main shaft (8).

6. The high-precision, fast-adjustable aperture mechanism according to claim 5, characterized in that: An encoder inner shaft mounting gasket is provided between the rolling bearing inner retaining ring (12) and the rotor of the encoder (6), and the encoder inner shaft mounting gasket is sleeved on the outer peripheral wall of the light-transmitting main shaft (8).

7. The high-precision, fast-adjustable aperture mechanism according to claim 6, characterized in that: The encoder inner shaft mounting gasket is a copper gasket, and the thickness of the copper gasket ranges from 0.4 mm to 0.6 mm.

8. The high-precision, fast-adjustable aperture mechanism according to claim 1, characterized in that: The diaphragm (4) is a fully closable diaphragm.

9. The high-precision, fast-adjustable aperture mechanism according to claim 1, characterized in that: A lever gasket (5) is provided between the aperture lever and the mounting bracket (1).

10. The high-precision, fast-adjustable aperture mechanism according to claim 1, characterized in that: A mounting protrusion is provided on the circumferential outer wall of the mounting bracket (1) near one end of the encoder stator, at least two mounting holes are provided along the circumference of the mounting protrusion, and an encoder mounting block (7) is provided on the outer circumferential wall of the encoder stator. The encoder mounting block (7) is provided in one-to-one correspondence with the mounting hole, and the two are connected by bolts.

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