A worm gear motion device

Abstract

A worm gear motion device, utilizing the worm gear transmission principle, overcomes the shortcomings of existing technologies, such as complex manufacturing, high cost, large clearances, and demanding assembly requirements. It is particularly suitable for precision adjustments in various optical industries. The rotary motion device designed in this invention mainly comprises a worm gear box, worm seat, worm gear, worm, rotating shaft, and spring pin. The rotation of the worm drives the worm wheel to rotate, and the worm maintains precise contact with the worm wheel through an elastic device composed of a spring pin and a spring. This invention features a simple structure, easy processing and assembly, and a compact design. The parts of this invention do not require particularly high machining precision for assembly, nor do they require precision grinding after assembly. It eliminates backlash and wear gaps, making it particularly suitable for precision adjustments and switching of optical components.

Description

Technical Field

[0001] This utility model relates to a rotary motion device, and more particularly to a worm gear motion device, which is applicable to the field of precision motion such as optical frames and device switching. Background Technology

[0002] The worm gear kinematic pair has a long history of use, is widely adopted, and is relatively inexpensive. It has several characteristics: 1. It achieves a large transmission ratio, reducing speed while increasing torque. 2. The meshing teeth of the worm gear and worm have line contact, resulting in high load-bearing capacity. 3. Worm transmission is equivalent to helical transmission, offering smooth operation and low noise. 4. When the lead angle of the worm is less than the equivalent friction angle between the meshing teeth, the mechanism possesses self-locking properties; it can also achieve reverse self-locking, meaning the worm gear cannot drive the worm to rotate. 5. Sliding friction transmission has lower efficiency and more severe wear.

[0003] In a wide range of optical fields, such as the precise angle adjustment and positioning of individual optical devices and the switching of motion between different optical devices, high precision is required for optical motion adjustment. Various reduction mechanisms are often needed for micro-stepping, with worm gears being a common method. For example, a typical two-phase stepper motor has a step angle of 1.8°, which, even with micro-stepping via a motor driver, is far from sufficient to meet the positioning accuracy requirements of various optical devices in the optical field. By configuring a worm gear mechanism at the motor output end, for example using a worm gear with a reduction ratio of 100, the actual output drive is only 0.018°, improving the step accuracy by 100 times and increasing the motor's output torque by tens of times.

[0004] Because the optical field demands very high positioning accuracy, the backlash (also known as reverse backlash) of worm gears is a highly sensitive factor. In practice, several methods exist to reduce backlash, such as: 1. Improving the precision of the worm gear and its mounting bearings. 2. Repeatedly assembling the worm gear to find the optimal assembly position with minimal backlash. 3. Repeatedly grinding the worm gear after assembly. However, even with increased machining precision for all parts, manufacturing errors are always present and cannot be eliminated. For example, different rotating axes can cause inconsistencies in tightness in other positions, even if some worm gear meshing achieves low backlash. This can lead to a sudden increase in the driving torque required for a tight transmission position during worm gear movement, exceeding the torque of the motor or other drives, causing the movement to "jam," and resulting in significant noise from the worm gear. Even if the aforementioned measures initially reduce backlash in the worm gear, friction and wear will increase it again. Summary of the Invention

[0005] To address the shortcomings of existing technologies and avoid the drawbacks of commonly used worm gears: 1. High-precision worm gears require higher processing costs. 2. High-precision worm gears require longer assembly times. 3. High-precision worm gears are prone to jamming. 4. High-precision worm gears suffer from limitations in clearance and hole positioning. This utility model provides a worm gear motion device that utilizes common components such as a worm gear box, worm seat, spring pin, and compression spring, achieving high-precision "zero backlash" worm gear motion.

[0006] The technical solution of this utility model is as follows:

[0007] A worm gear motion device, characterized in that it includes:

[0008] The worm gear box (1) is square in shape and has a cylindrical hole (101) in the middle of the interior, in which a worm gear (3) and a pair of second bearings (15) are installed.

[0009] The worm seat (2) is L-shaped and fixed to the square slot (102) on the side of the worm gear box (1) by screws. The long side of the L-shaped worm seat (2) is provided with a bearing mounting hole (204), in which the worm (4) and the first bearing (9) are installed. The elastic device consists of a compression spring (5) and a spring pin (6). One end of the spring pin (6) is embedded in the compression spring (5), and the other end abuts against the side wall of the long slot (201) of the worm seat (2), so that the worm (4) continuously presses against the worm wheel (3). The coupling (7) connects the end of the worm (4) to the output shaft of the drive source (16). The bearing cover (8) is fixed on the worm seat (2) and is used to press the first bearing (9). The first bearing ring (11) and the second bearing ring (13) are fixed on the rotating shaft (12) and the worm gear box (1) respectively and are used to press the second bearing (15).

[0010] Furthermore, the cylindrical hole (101) of the worm gear box (1) has concave cylindrical surfaces (103) at both ends, and the bearing pressure ring (13) is installed in the concave cylindrical surface (103) to press and fix the bearing (15).

[0011] Furthermore, the L-shaped long side of the worm gear seat (2) is provided with a through long slit (201), which divides the L-shaped long side into two elastically deformable parts, one of which is provided with a pin mounting hole (203) for installing an elastic device.

[0012] Furthermore, the protruding cylindrical end of the spring pin (6) is embedded in the compression spring (5), and the other end contacts the side wall of the long slot (201) of the worm seat (2). The worm (4) is kept in close engagement with the worm wheel (3) by the elastic force of the compression spring (5).

[0013] Furthermore, the side of the worm gear box (1) is provided with a pin hole (104), through which the pin passes and connects to the worm seat (2) to enhance the fixing stability of the worm seat (2).

[0014] Furthermore, the worm (4) is installed in the cylindrical hole (204) of the worm seat (2) by a pair of bearings (9), and the bearing cap (8) is fixed to the end of the worm seat (2) by screws to axially press the bearing (9).

[0015] Furthermore, the coupling (7) is an elastic coupling, with its two ends connected to the end shaft of the worm (4) and the output shaft of the drive source (16) respectively, to compensate for axial and radial installation deviations.

[0016] Furthermore, the worm gear box (1) has mounting holes at three right-angle positions, through which the entire device can be fixed to an external device.

[0017] Furthermore, the preload of the elastic device can be adjusted by replacing the compression spring (5) with one of different specifications or by adjusting the installation position of the spring pin (6).

[0018] Furthermore, the meshing surfaces of the worm (4) and the worm wheel (3) maintain contact pressure under the action of the elastic device, thereby achieving zero backlash during the transmission process.

[0019] Furthermore, the L-shaped short side of the worm gear seat (2) is provided with multiple threaded holes for fixing the drive source (16) and connecting the worm gear box (1).

[0020] Furthermore, the worm gear (3) is installed in the cylindrical hole (101) of the worm gear box (1) via a rotating shaft (12), and the two ends of the rotating shaft (12) are supported by bearings (15).

[0021] Furthermore, the long slot (201) of the worm gear seat (2) is coaxially arranged with the pin mounting hole (203), and the axis of the spring pin (6) is parallel to the axis of the worm (4).

[0022] Furthermore, the bearing cap (8) is fixed to the end face of the worm gear seat (2) by screws to axially position the bearing (9).

[0023] Furthermore, the square slot (102) of the worm gear box (1) is fixed to the L-shaped short side of the worm seat (2) by screws.

[0024] Compared with the prior art, the technical effects of this utility model are as follows:

[0025] This invention utilizes common mechanical parts such as worm gear boxes, worm seats, spring pins, and compression springs, which are few in number and easy to manufacture. The worm gear and other structural parts used do not require particularly high machining precision, thus eliminating the backlash in the worm gear mechanism. This invention reduces the assembly difficulty of precision worm gear mechanisms, saving assembly time and workload. The worm gear mechanism of this invention features "zero backlash," maintaining this effect even after prolonged wear and tear. This invention allows adjustment of the contact force between the worm gear and worm, preventing jamming while maintaining zero backlash in the worm gear mechanism.

[0026] This utility model has a simple structure, is easy to process and assemble, and features zero backlash. It is particularly suitable for precision positioning and switching of optical devices. Attached Figure Description

[0027] Figure 1 This is a three-dimensional schematic diagram of a worm gear motion device according to the present invention.

[0028] Figure 2 This is a top sectional view of a worm gear motion device according to the present invention.

[0029] Figure 3 This is a front view sectional view of a worm gear motion device according to this utility model.

[0030] Figure 4 This is a schematic diagram of the worm gear box of a worm gear motion device according to this utility model.

[0031] Figure 5 This is a schematic diagram of the worm seat of a worm gear motion device according to this utility model.

[0032] Figure 6 This is a schematic diagram of the worm wheel in a worm gear motion device according to this utility model.

[0033] Figure 7 This is a schematic diagram of the worm of a worm gear motion device according to this utility model.

[0034] Figure 8 This is a schematic diagram of the spring pin of a worm gear motion device according to this utility model. Detailed Implementation

[0035] The following detailed description, in conjunction with the accompanying drawings and embodiments, will enable those skilled in the art to clearly understand the technical solution and advantages of this utility model.

[0036] The worm gear motion device of this utility model, such as Figure 1-3As shown, it includes a worm gear box (1), a worm seat (2), a worm gear (3), a worm (4), a compression spring (5), a spring pin (6), a coupling (7), a bearing cover 1 (8), a bearing 1 (9), a mounting surface (10), a pressure ring 1 (11), a rotating shaft (12), a bearing pressure ring 2 (13), a spacer (14), and a bearing 2 (15).

[0037] like Figure 4 As shown, the worm gear box (1) has a square structure with a central cylindrical hole (101) for mounting the worm gear (3) and a pair of second bearings (15). A concave cylindrical surface (103) is provided along the circumference of the central cylindrical hole (101) for placing the second bearing retaining ring (13). The second bearing (15) is fixed by a spacer (14) and the second bearing retaining ring (13).

[0038] The worm gear box (1) has a square slot structure (102) on its side for mounting the worm seat (2). The worm gear box (1) has pin holes (104) to strengthen the fixation of the worm seat (2) and prevent loosening. The worm gear box (1) also has mounting holes at three right angles for fixing the entire device to external optical equipment. During assembly, the second bearing (15) and spacer (14) are inserted into the cylindrical hole (101) of the worm gear box. The worm wheel (3) is installed and the bearing is pressed by the second bearing retainer (13) to ensure that the worm wheel can rotate smoothly.

[0039] like Figure 5 As shown, the worm gear seat (2) has an approximately L-shaped structure. Its long L-shaped side has a long slit (201) and a flexible joint (202), as well as a pin mounting hole (203) for installing the pin (6) and a cylindrical hole (204) for the bearing (9) to be nested for the rotation of the worm. The first bearing cap (8) is fixed to the end of the long L-shaped side to press the bearing (1). The short L-shaped side of the worm gear seat (2) has a screw hole for fixing the drive source (16) and a screw hole for fixing the entire worm gear seat (2) to the worm gear box (1). During the assembly process, the worm (4) and a pair of first bearings (9) are first installed into the bearing holes (204) of the worm gear seat (2). Then, the bearing cap (8) is installed to fix the first bearing. Then, the compression spring (5) and the pin (6) are sequentially installed into the pin mounting holes (203) of the worm gear seat (2) so that the worm is always pressed against the worm gear under the action of the spring force, eliminating the meshing clearance. One end of the spring pin (6) has a protruding cylindrical shape 601, into which a compression spring (5) is embedded. The spring force keeps the worm (4) in close contact with the worm wheel (3) at all times, and it can maintain zero distance even after long-term wear. The flexible joint (202) allows the worm to float slightly, preventing it from getting stuck due to local overtightness caused by machining errors.

[0040] Finally, the end shaft of the worm gear is connected to the power output shaft of the drive source (16) via a coupling (7). The motor drives the worm gear to rotate, and the worm gear drives the worm wheel (3) to rotate, thereby achieving precise angle adjustment. Due to the effect of the elastic device, there is no backlash in the transmission process, and the operation is smooth and the noise is low.

[0041] This invention achieves high-precision, zero-backflow transmission by optimizing the worm gear structure and introducing an elastic device. Its simple structure and convenient manufacturing significantly reduce assembly difficulty and cost, making it particularly suitable for precision motion control in the optical field.

Claims

1. A worm and gear movement device, characterized in that, include: The worm gear box (1) is square in shape and has a cylindrical hole (101) in the middle of the interior, in which a worm gear (3) and a pair of second bearings (15) are installed. The worm seat (2) is L-shaped and fixed to the square slot (102) on the side of the worm gear box (1) by screws. The long side of the L-shaped worm seat (2) is provided with a bearing mounting hole (204), in which the worm (4) and the first bearing (9) are installed. The elastic device consists of a compression spring (5) and a spring pin (6). One end of the spring pin (6) is embedded in the compression spring (5), and the other end abuts against the side wall of the long slot (201) of the worm seat (2), so that the worm (4) continuously presses against the worm wheel (3). The coupling (7) connects the end of the worm (4) to the output shaft of the drive source (16). The bearing cover (8) is fixed on the worm seat (2) and is used to press the first bearing (9). The first bearing ring (11) and the second bearing ring (13) are fixed on the rotating shaft (12) and the worm gear box (1) respectively and are used to press the second bearing (15). The L-shaped long side of the worm gear seat (2) is provided with a through long slit (201), which divides the L-shaped long side into two elastically deformable parts, one of which is provided with a pin mounting hole (203) for installing an elastic device. The protruding cylindrical end of the spring pin (6) is embedded in the compression spring (5), and the other end contacts the side wall of the long slot (201) of the worm seat (2). The worm (4) is kept in close engagement with the worm wheel (3) by the elastic force of the compression spring (5).

2. The worm and gear motion device according to claim 1, characterized in that, The cylindrical hole (101) of the worm gear box (1) has concave cylindrical surfaces (103) at both ends. The second bearing pressure ring (13) is installed in the concave cylindrical surface (103) to press and fix the second bearing (15).

3. The worm and gear motion device of claim 1, wherein: The worm gear box (1) has a pin hole (104) on its side. The pin passes through the pin hole (104) and connects to the worm seat (2) to enhance the fixing stability of the worm seat (2).

4. The worm gear motion device according to claim 1, characterized in that: The worm (4) is installed in the bearing mounting hole (204) of the worm seat (2) by a pair of first bearings (9), and the bearing cover (8) is fixed to the end of the worm seat (2) by screws to axially press the first bearings (9).

5. The worm gear motion device according to claim 1, characterized in that: The coupling (7) is an elastic coupling, with its two ends connected to the end shaft of the worm (4) and the output shaft of the drive source (16) respectively, to compensate for axial and radial installation deviations.

6. The worm gear motion device according to claim 1, characterized in that: The worm gear box (1) has mounting holes at three right-angle positions, through which the entire device can be fixed to an external device.

7. The worm gear motion device according to claim 1, characterized in that: The meshing surfaces of the worm (4) and worm wheel (3) maintain contact pressure under the action of the elastic device, thereby achieving zero backlash during the transmission process.

8. The worm gear motion device according to claim 1, characterized in that: The short side of the L-shaped worm gear seat (2) is provided with multiple threaded holes for fixing the drive source (16) and connecting the worm gear box (1).

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