A precision gear positioning structure and an encoder

Abstract

The application relates to a precision gear positioning structure and an encoder, and provides a precision gear positioning structure which comprises a positioning assembly and a gear, the positioning assembly comprises a positioning frame, positioning beads, elastic elements and a cylinder, the positioning beads are combined with the outer edge tooth valleys of the gear, when the gear rotates, the positioning beads can be moved from one outer edge tooth valley of the gear to another adjacent outer edge tooth valley, the elastic elements and the positioning beads are sequentially installed into the cylinder, the cylinder is a flexible cylinder, the positioning frame is provided with an opening, a U-shaped groove is arranged in the opening, and the flexible cylinder is clamped into the U-shaped groove to form interference fit connection.

Description

Technical Field

[0001] This application relates to the field of precision sensor technology, and in particular to a precision gear positioning structure and encoder. Background Technology

[0002] In existing encoder assembly technology, a cylindrical roller is first glued to the outer edge of the gear tooth groove. A spring is then installed to push the roller, causing it to rotate in conjunction with the gear. However, installing the spring requires using tweezers to hold it and insert it into a groove in the support frame. A cover plate with an abutment is then installed over the groove to prevent the spring from popping out during encoder operation. Since the spring is a small part, this method of using tweezers to hold and install the spring is time-consuming, and burrs on the upper surface of the cover plate can affect the encoder's installation accuracy.

[0003] In existing technologies, half or a small portion of the positioning bead / positioning pin is typically locked inside a spring, with both ends relying on the contact between the spring and the gear to prevent disengagement. In this method, when the gear is turned, the positioning bead is unstable relative to the outer edge of the gear teeth and is prone to displacement and vibration.

[0004] Encoders are high-precision sensors that require extremely high accuracy in installation and assembly. In existing technologies, vibrations caused by subsequent installation processes often affect the installation accuracy of previous processes, thus negatively impacting the overall installation accuracy. Summary of the Invention

[0005] Based on the aforementioned problems in the prior art, this patent provides a precision gear positioning structure and encoder, aiming to solve one or more of the problems in the prior art.

[0006] This application provides a precision gear positioning structure, including a positioning component and a gear. The positioning component includes a positioning frame, a positioning bead, an elastic element, and a cylinder. The positioning bead contacts and engages with the outer edge tooth valley of the gear. When the gear is rotated, the positioning bead can move from one outer edge tooth valley of the gear to an adjacent outer edge tooth valley.

[0007] The elastic element and the positioning bead are sequentially installed inside the cylinder.

[0008] Preferably, the cylinder is a flexible cylinder, and the positioning frame has an opening with a U-shaped groove inside the opening. The flexible cylinder is inserted into the U-shaped groove to form an interference fit connection. The precision gear positioning structure of this application adopts an open-type positioning frame, and the upper surface of the positioning frame does not need to be fitted with a cover plate to abut against the fixing spring.

[0009] Preferably, more than half of the positioning bead is located inside the inner cavity of the cylinder. In the prior art, half or a small portion of the positioning bead is usually stuck in the spring, and the two ends are kept from disengaging by the contact between the spring and the gear. In this way, when the gear is turned, the positioning bead is unstable when rotating relative to the outer edge of the gear teeth, and is prone to displacement and vibration.

[0010] Preferably, the cylinder includes an end face and a cylinder wall. The cylinder wall extends away from the end face and forms a blocking part at the end. The blocking part forms a circular opening. The diameter of the circular opening is smaller than the diameter of the positioning bead. The blocking part can prevent the positioning bead from popping out of the inner cavity of the cylinder.

[0011] Preferably, the cylinder can be a steel cylinder. In the initial blank, the inner diameter of the cylinder is larger than the outer diameter of the positioning bead. After the elastic element and the positioning bead are installed into the cylinder in sequence, the opening of the cylinder is bent inward to form a blocking part.

[0012] Preferably, the cylinder may also be made of other rigid materials.

[0013] Preferably, during installation, the positioning bead can be inserted through the circular opening formed by the blocking part and accommodated inside the cylinder. The blocking part ensures that the positioning bead can be installed inside the cylinder while effectively preventing it from popping out after installation.

[0014] Preferably, the positioning frame has two fixing posts inside its opening, and the distance between the two fixing posts is less than the outer diameter of the cylinder. The fixing posts are square, and their height is less than the height of the upper surface of the positioning frame.

[0015] Preferably, the cylinder can be made of steel or other rigid materials, and the cylinder is fixed to the positioning frame by adhesive bonding. In another embodiment, the U-shaped groove of the positioning frame and the two fixing posts inside the positioning frame opening can be made of flexible materials, and a tight connection is achieved by interfering with the rigid cylinder and inserting it into the positioning frame.

[0016] Preferably, the periphery of the positioning frame opening forms a rectangular outer wall.

[0017] Preferably, the elastic element is a spring. After installation, the spring is in a compressed state, forming a preload thrust on the positioning bead. A small portion of the positioning bead protrudes from the cylinder and contacts the outer edge of the gear teeth. This structure greatly improves the stability of the positioning bead when it contacts the gear teeth during gear rotation / shifting.

[0018] Preferably, the precision gear positioning structure further includes a pin, and the cylinder wall is provided with an L-shaped opening, the L-shaped opening including an axial opening section and a radial opening section. The pin can pass through the L-shaped opening and be inserted into the gap between adjacent coils of the spring. The pin can move along the axial direction of the cylinder in the axial opening section of the L-shaped opening and be locked in the radial opening section of the L-shaped opening.

[0019] This application also provides an encoder, which is equipped with a moving grating and a fixed grating, and the encoder is equipped with the above-mentioned precision gear positioning structure.

[0020] This application provides a method for installing a precision gear positioning structure, including the following steps:

[0021] Step 1: Install the cylinder containing the spring and positioning ball into the positioning frame;

[0022] Step 2: Install the gear into the encoder so that the gear teeth contact and engage with the positioning beads;

[0023] Step 3: Apply glue to the contact surface between the cylinder and the positioning frame, and fix the cylinder to the positioning frame to form a positioning structure in which the positioning bead and the gear are in contact and engaged.

[0024] Another embodiment of this application provides a method for installing a precision gear positioning structure, including the following steps:

[0025] Step 1: Install the spring and positioning ball into the cylinder in sequence;

[0026] Step 2: Pass the pin through the L-shaped opening and insert it into the gap between the adjacent coils of the spring;

[0027] Step 3: Move the pin along the axial direction of the cylinder to the junction of the axial opening and the radial opening in the axial opening section of the L-shaped opening.

[0028] Step 4: Lock the pin within the radial opening section of the L-shaped opening. At this time, the spring does not generate a pre-tightening thrust on the positioning bead.

[0029] Step 5: Install the cylinder onto the fixing frame;

[0030] Step 6: Install the gear into the encoder;

[0031] Step 7: Pull out the pin so that the positioning bead contacts the outer edge of the gear teeth. At this time, the spring generates a preload force on the positioning bead.

[0032] The precision gear positioning structure and encoder described in this application have the following advantages:

[0033] (1) The precision gear positioning structure of this application adopts an open structure. The upper surface of the positioning frame does not need to be fitted with a cover plate to abut against the fixing spring. It is fixed to the positioning frame by the flexible interference fit of the cylinder. The solution of this application not only simplifies the structure and installation process by eliminating a cover plate component and saving costs, but also improves the installation and assembly accuracy because the cover plate may be uneven or have burrs.

[0034] (2) In the prior art, half or a small part of the positioning bead is usually stuck in the spring, and the two ends rely on the contact between the spring and the gear to ensure that they do not disengage. In this way, when the gear is turned / rotated, the positioning bead is unstable when rotating relative to the outer edge of the gear teeth and is prone to displacement and vibration. This application adopts the setting of a cylindrical blocking part. After the spring is installed, it is in a compressed state, which forms a pre-tightening thrust on the positioning bead. The setting of the blocking part allows a small part of the positioning bead to protrude from the cylinder and contact the outer edge of the gear teeth. This structure greatly improves the stability of the positioning bead when it contacts the gear teeth when the gear is rotated / turned.

[0035] (3) An L-shaped opening is provided on the wall of the cylinder. The L-shaped opening includes an axial opening section and a radial opening section. The pin can pass through the L-shaped opening and be inserted into the gap between adjacent coils of the spring. The pin can move along the axial opening section of the L-shaped opening along the axial direction of the cylinder and be locked within the radial opening section of the L-shaped opening. This structure can avoid the difficulty of installation due to excessive tightness between the positioning ball and the gear, and also avoids the defect of affecting assembly accuracy caused by installation vibration. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the internal structure of the encoder in this application;

[0037] Figure 2 This is another schematic diagram of the internal structure of the encoder in this application;

[0038] Figure 3 This is a schematic diagram of a cylinder with positioning beads installed in the precision gear positioning structure of this application;

[0039] Figure 4 This is a schematic diagram of a cylinder with positioning beads installed in another embodiment of the precision gear positioning structure of this application;

[0040] Figure 5 This is a cross-sectional view of a cylinder with a spring and a positioning ball installed in the precision gear positioning structure of this application.

[0041] Figure 6 This is a schematic diagram of the positioning component of the precision gear positioning structure of this application.

[0042] Explanation of reference numerals in the attached drawings: 1-Encoder, 2-Positioning assembly, 21-Cylinder, 211-End face, 212-Cylinder wall, 213-Through hole, 214-Blocking part, 22-Positioning bead, 23-Elastic element, 24-L-shaped opening, 25-Pin, 26-Positioning frame, 261-Outer wall, 262-Fixing post, 263-U-shaped groove, 3-Gear, 4-Fixed grating, 5-Moving grating. Detailed Implementation

[0043] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0044] To simplify the disclosure of this invention, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the invention. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, examples of various specific processes and materials are provided in this invention, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0045] Example 1

[0046] like Figure 1-2As shown, this application provides a precision gear positioning structure, including a positioning component 2 and a gear 3. The positioning component 2 includes a positioning frame 26, a positioning bead 22, an elastic element 23, and a cylinder 21. The positioning bead 22 engages with the outer edge tooth valley of the gear 3. When the gear 3 is rotated, the positioning bead 22 can move from one outer edge tooth valley of the gear 3 to an adjacent outer edge tooth valley. The cylinder 21 is made of steel. After the elastic element 23 and the positioning bead 22 are sequentially installed inside the cylinder 21, the opening of the cylinder is bent inward to form a blocking part 214. The positioning frame 26 has an opening, and a U-shaped groove 263 is provided in the opening. The cylinder 21 is installed into the U-shaped groove of the fixing frame 26. Glue is dripped onto the contact surface between the cylinder and the positioning frame to fix the cylinder to the positioning frame.

[0047] like Figure 3 As shown, more than half of the positioning bead 22 is located inside the inner cavity of the cylinder 21. Figure 5 As shown, the cylinder 21 includes an end face 211 and a cylinder wall 212. The cylinder wall 212 extends away from the end face 211 and forms a blocking part 214 at the end. The blocking part 214 forms a circular opening. The diameter of the circular opening is smaller than the diameter of the positioning bead 22. The blocking part 214 can prevent the positioning bead 22 from popping out of the inner cavity of the cylinder 21.

[0048] like Figure 6 As shown, two fixing posts 262 are provided inside the opening of the positioning frame 26, and a rectangular outer wall 261 is formed around the opening of the positioning frame 26.

[0049] Example 2

[0050] like Figure 1-2 As shown, this application provides a precision gear positioning structure, including a positioning component 2 and a gear 3. The positioning component 2 includes a positioning frame 26, a positioning bead 22, an elastic element 23, and a cylinder 21. The positioning bead 22 engages with the outer edge tooth valley of the gear 3. When the gear 3 is rotated, the positioning bead 22 can move from one outer edge tooth valley of the gear 3 to an adjacent outer edge tooth valley. The elastic element 23 and the positioning bead 22 are sequentially installed inside the cylinder 21. The cylinder 21 is a flexible cylinder. The positioning frame 26 has an opening, and a U-shaped groove 263 is provided in the opening. The flexible cylinder 21 is inserted into the U-shaped groove to form an interference fit connection.

[0051] like Figure 3 As shown, more than half of the positioning bead 22 is located inside the inner cavity of the cylinder 21. Figure 5As shown, the cylinder 21 includes an end face 211 and a cylinder wall 212. The cylinder wall 212 extends away from the end face 211 and forms a blocking part 214 at the end. The blocking part 214 forms a circular opening. The diameter of the circular opening is smaller than the diameter of the positioning bead 22. The blocking part 214 can prevent the positioning bead 22 from popping out of the inner cavity of the cylinder 21.

[0052] During installation, the positioning bead 22 can be inserted through the circular opening formed by the blocking part 214 and accommodated inside the cylinder 21.

[0053] like Figure 6 As shown, the positioning frame 26 has two fixing posts 262 inside its opening, and the distance between the two fixing posts 262 is less than the outer diameter of the cylinder 21. The cylinder 21 is inserted between the two fixing posts 262. The fixing posts 262 are square fixing posts, and the height of the fixing posts 262 is less than the height of the upper surface of the positioning frame 26. The outer perimeter of the opening of the positioning frame 26 forms a rectangular outer wall 261.

[0054] Example 3

[0055] like Figure 1-2 As shown, this application provides a precision gear positioning structure, including a positioning component 2 and a gear 3. The positioning component 2 includes a positioning frame 26, a positioning bead 22, an elastic element 23, and a cylinder 21. The positioning bead 22 contacts and engages with the outer edge tooth valley of the gear 3. When the gear 3 is rotated, the positioning bead 22 can move from one outer edge tooth valley of the gear 3 to an adjacent outer edge tooth valley. The elastic element 23 and the positioning bead 22 are sequentially installed inside the cylinder 21. The cylinder 21 is a flexible cylinder. The positioning frame 26 has an opening, and a U-shaped groove 263 is provided in the opening. The flexible cylinder 21 is inserted into the U-shaped groove to form an interference fit connection. The elastic element 23 is a spring.

[0056] like Figure 4 As shown, the precision gear positioning structure also includes a pin 25. An L-shaped opening 24 is provided on the cylinder wall 212 of the cylinder 21. The L-shaped opening 24 includes an axial opening section and a radial opening section. The pin 25 can pass through the L-shaped opening and be inserted into the gap between adjacent coils of the spring. The pin 25 can move along the axial direction of the cylinder 21 in the axial opening section of the L-shaped opening and be locked in the radial opening section of the L-shaped opening.

[0057] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, an electrical connection, or a connection that allows for communication; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0058] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

Claims

1. A precision gear positioning structure, comprising a positioning component (2) and a gear (3), wherein the positioning component (2) comprises a positioning frame (26), a positioning bead (22), an elastic element (23), and a cylinder (21), wherein the positioning bead (22) contacts and engages with the outer edge tooth valley of the gear (3), and when the gear (3) is rotated, the positioning bead (22) can move from one outer edge tooth valley of the gear (3) to an adjacent outer edge tooth valley, characterized in that: The elastic element (23) is a spring. The elastic element (23) and the positioning bead (22) are installed in the cylinder (21) in sequence. The positioning frame (26) has an opening. A U-shaped groove (263) is provided in the opening. The cylinder (21) is installed in the U-shaped groove (263). More than half of the positioning bead (22) is located in the inner cavity of the cylinder (21). The precision gear positioning structure also includes a pin (25). An L-shaped opening (24) is provided on the cylinder wall (212) of the cylinder (21). The L-shaped opening (24) includes an axial opening section and a radial opening section. The pin (25) can pass through the L-shaped opening and be inserted into the gap between the adjacent coils of the spring. The pin (25) can move along the axial direction of the cylinder (21) in the axial opening section of the L-shaped opening and be locked in the radial opening section of the L-shaped opening. At this time, the spring does not generate a pre-tightening thrust on the positioning bead. The cylinder is a flexible cylinder, and the flexible cylinder (21) is inserted into the U-shaped groove to form an interference fit connection; The cylinder (21) includes an end face (211) and a cylinder wall (212). The cylinder wall (212) extends away from the end face (211) and forms a blocking part (214) at the end. The blocking part (214) forms a circular opening. The diameter of the circular opening is smaller than the diameter of the positioning bead (22). The blocking part (214) can prevent the positioning bead (22) from popping out of the inner cavity of the cylinder (21). The blocking part (214) is flexible, and during installation, the positioning bead (22) can be inserted through the circular opening formed by the blocking part (214) and accommodated in the cylinder (21).

2. The precision gear positioning structure according to claim 1, characterized in that, The cylinder (21) is fixed to the positioning frame (26) by means of adhesive.

3. The precision gear positioning structure according to claim 1, characterized in that, The positioning frame (26) has two fixed posts (262) inside its opening, and the distance between the two fixed posts (262) is less than the outer diameter of the cylinder (21).

4. The precision gear positioning structure according to claim 3, characterized in that, The outer periphery of the opening of the positioning frame (26) forms a rectangular outer wall (261).

5. An encoder, characterized in that, The encoder is equipped with a precision gear positioning structure as described in any one of claims 1-4, and the encoder is installed with the precision gear positioning structure according to the following steps: Step 1: Install the spring and positioning ball into the cylinder in sequence; Step 2: Pass the pin through the L-shaped opening and insert it into the gap between the adjacent coils of the spring; Step 3: Move the pin along the axial direction of the cylinder to the junction of the axial opening and the radial opening in the axial opening section of the L-shaped opening. Step 4: Lock the pin within the radial opening section of the L-shaped opening. At this time, the spring does not generate a pre-tightening thrust on the positioning bead. Step 5: Install the cylinder onto the positioning frame; Step 6: Install the gear into the encoder; Step 7: Pull out the pin so that the positioning bead contacts the outer edge of the gear teeth. At this time, the spring generates a preload force on the positioning bead.

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