Straight tooth-face gear transmission design method for high-speed rotary dobby

Abstract

The invention provides a straight tooth-face gear transmission design method for a high-speed rotary dobby, which comprises the following steps of: replacing a Gleason tooth spiral bevel gear pair between a driving shaft and a cam output mechanism in the dobby with a straight tooth face gear pair, and designing a straight tooth face gear pair on the basis of relevant parameters of a bevel pinion and a bull gear of the spiral bevel gear pair; and calculating and determining corresponding parameters of the straight spur gear and the face gear of the replaced straight tooth face gear pair. According to the invention, on the premise of not changing any parts and interfaces except the tooth form of the gear in the dobby, orthogonal transmission and rotation speed increase can be realized, the structure is simple to mount, and the characteristics of light weight and space saving are realized; the point contact characteristic is not affected by installation errors, the movement consistency of the dobby can be guaranteed, and the dobby has high universality.

Description

Technical Field

[0001] The invention patent belongs to the technical field of gear transmission structure for textile machinery, and in particular relates to a design method for spur-face gear transmission for high-speed rotating multi-arm machines. Background Art

[0002] As a shedding device of textile machinery, the dobby machine mostly adopts a single-stage spiral bevel gear pair transmission structure. Its active gear is driven by the drive shaft 1, and the motion output by the driven gear is transmitted to the longitudinal frame through the cam output mechanism 2 to drive the corresponding textile machinery to work. The high-speed development of textile machinery depends on the movement speed and movement accuracy of the rotary dobby machine, and the movement speed and movement accuracy of the rotary dobby machine directly depend on the gear transmission at its input end. At present, the gear transmission at the input end of the most advanced rotary dobby machine adopts a point-contact Gleason tooth spiral bevel gear pair, in which the large and small gears are determined by the structural dimensions of the dobby machine. The following defects of this point-contact spiral bevel gear pair restrict the high-speed movement accuracy of the dobby machine: first, it requires high installation accuracy to ensure the point contact properties and reasonable contact trajectory; second, the shape of the large gear determines that its volume and weight are large, and it is the largest and heaviest part on the dobby machine, and its high-speed movement accuracy is difficult to ensure; third, the manufacturing cost is high, and in order to ensure the point contact characteristics, its small bevel gear is actually an adaptation gear processed by the idea of ​​repair, and the meshing properties of different small bevel gears and large gears are not consistent. To this end, the present invention patent intends to disclose a spur-face gear transmission for a multi-arm machine. The driving gear in this gear transmission adopts the simplest spur cylindrical gear among gears, and the size of the face gear adopts the structural size that does not interfere with the driven gear in the arc bevel gear pair, so as to ensure that any parts and interfaces in the multi-arm machine except the gear tooth shape are not changed. This spur-face gear transmission is easy to install, and its point contact characteristics will not be affected by installation errors, which can ensure the consistency of the multi-arm machine's movement. During use, there is no need to adjust the installation position of the spur gear to adapt to the point contact trajectory requirements of the face gear, and the production cost of the spur cylindrical gear is low and it is easy to replace after damage. Summary of the invention

[0003] In order to solve the problems existing in the prior art, the present invention adopts the following technical solutions: A design method for a spur-face gear transmission for a high-speed rotary multi-arm machine is provided. The Gleason-tooth spiral bevel gear pair between the driving shaft and the cam output mechanism in the multi-arm machine is replaced with a spur face gear pair, wherein the driving gear connected and driven by the driving shaft is replaced by a spur cylindrical gear from a small bevel gear of the spiral bevel gear pair, and the driven gear connected and driven by the cam output mechanism is replaced by a face gear from a large gear of the spiral bevel gear pair. First measure the following parameters: The shaft diameter of the drive shaft; the maximum outer diameter of the small bevel gear of the spiral bevel gear pair ; Module and pressure angle of spiral bevel gear pair; Then determine the parameters of the spur gear and face gear as follows: Spur gear mounting hole diameter d n Equal to the diameter of the drive shaft; Number of teeth on spur gears z p Calculated by formula 1: Formula 1 in, is the tooth addendum coefficient of the spur gear; d pa is the tooth tip diameter of the spur gear, which is not greater than the maximum outer diameter of the small bevel gear of the spiral bevel gear pair being replaced. ; m is The module of the spur gear and the module of the spur gear m and pressure angle α The module and pressure angle of the replaced spiral bevel gear pair should be the same; The outer radius of the face gear teeth R of , inner radius R if , Number of teeth z f Calculated by equation 2 and equation 3 respectively: Formula 2 Formula 3 The gear teeth of the face gear are made by gear shaping. m Take the module value corresponding to the spur gear, α Take the pressure angle value corresponding to the spur gear; z s The number of teeth of the gear shaping cutter ， The number of teeth on the spur gear z p The relationship satisfies formula 4: Formula 4 The number of teeth of the gear cutter z s Ratio of spur gear teeth to z p One to three more teeth are required to ensure that the face gear machined by the gear shaping cutter and the spur-face gear transmission formed by the spur gear are in point contact.

[0004] Further, in Formula 2 and Formula 3, take and , the number of teeth of the gear shaping cutter is knownz s , modulus m , pressure angle α , solve for the number of teeth on the face gear z f ;in, The diameter of the central through hole opened in the center of the large gear for the lubrication system pipeline to pass through, It is twice the distance from the hole wall of the locating piece installation hole on the large gear wheel seat that is closest to the wheel axle center to the wheel axle centerline.

[0005] Furthermore, the maximum outer diameter of the wheel seat of the face gear D p The value is not greater than the maximum outer diameter of the wheel seat of the large gear , the thickness of the wheel seat of the face gear h The value of 1 is not greater than the thickness of the wheel seat of the large gear .

[0006] Furthermore, the outer diameter of the face gear teeth R of Should meet 2 R of < D h ,this D h The distance from the wall of the locating piece installation hole opened on the face gear wheel seat and closest to the wheel axle center for installing the locating piece to the wheel axle centerline is twice the distance.

[0007] Compared with the prior art, the beneficial effects of the present invention are: The present invention replaces the transmission between the driving shaft and the cam output mechanism of the high-speed rotary multi-arm machine with a spur-face gear transmission, and designs and calculates the replaced spur-face gear transmission structure according to the original gear pair size, ensuring that the improvement is based on the premise that any parts and interfaces except the gear tooth profile in the multi-arm machine are not changed, and the theoretical reference position of the spur-face gear transmission is calculated based on the meshing principle to achieve orthogonal transmission and speed increase; the structure is simple to install and has the characteristics of lightweight and space saving; its point contact characteristics will not be affected by installation errors, and the consistency of the multi-arm machine movement can be ensured.

[0008] The present invention ensures that the point contact trajectory requirements of the face gear can be met without adjusting the installation position of the spur gear, and the determination of various parameters of the spur cylindrical gear and the face gear is simple and quick, with high versatility.

[0009] In the gear transmission system, the gears on the high-speed shaft often face a high risk of damage. The use of spur-face gear transmission can significantly reduce production costs, and once the gear is damaged, it is also very convenient to replace it. In addition, the spur cylindrical gear transmission has relatively loose requirements on installation accuracy, which not only simplifies the installation process, but also greatly reduces the installation cost. It is worth mentioning that this transmission method shows a high fault tolerance performance along the tooth surface direction, which can effectively deal with slight deviations during the installation process, thereby ensuring the stable operation of the transmission system. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a schematic diagram of the original transmission structure of the multi-arm machine targeted by the present invention; Figure 2 It is a structural schematic diagram of the small bevel gear in the original transmission structure; Figure 3 It is a structural schematic diagram of the large gear in the original transmission structure; Figure 4 It is a schematic diagram of the structure of a multi-arm machine replaced with a spur-face gear transmission; Figure 5 It is a structural schematic diagram of a spur gear; Figure 6 It is a structural schematic diagram of the face gear; Figure 7 It is a schematic diagram of the spur-face gear transmission structure in the present invention. DETAILED DESCRIPTION

[0011] In order to make the purpose and technical solution of the present invention clearly and completely described, and the advantages more clearly understood, the embodiments of the present invention are further described in detail in conjunction with the accompanying drawings. It should be understood that the specific embodiments described here are part of the embodiments of the present invention, not all of them, and are only used to explain the embodiments of the present invention, and are not used to limit the embodiments of the present invention. All other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0012] Figure 1 The figure shows the structure of a multi-arm machine using a spiral bevel gear pair for transmission before improvement. In the figure, the driving gear driven by the driving shaft 1 adopts the small bevel gear 3 of the spiral bevel gear pair, and the driven gear adopts the large gear 4 of the spiral bevel gear pair. The motion output by the large gear 4 is transmitted to the longitudinal frame through the cam output mechanism 2 to drive the corresponding textile machinery to work.

[0013] The primary design principle of the present invention to replace the spiral bevel gear pair with the spur-face gear transmission is not to change any parts and interfaces in the multi-arm machine except the gear tooth shape. Figure 4As shown, a spur gear 5 is used as the driving gear in the new transmission structure (spur-face gear transmission), that is, the driving gear is replaced by the small bevel gear 3 in the spiral bevel gear pair with the spur gear 5.

[0014] Depend on Figure 2 As shown, the small bevel gear has a hole diameter of The mounting hole is installed on the drive shaft 1, and the large end outer diameter of the small bevel gear It determines the minimum distance and relative relationship between the driving gear and the housing in the radial direction.

[0015] Before replacement, it is necessary to measure the relevant parameters and dimensions of the original arc bevel gear pair between the rotary multi-arm machine drive shaft 1 and the cam output mechanism 2, including the following parameters: Drive shaft 1 diameter ; The distance from the axis of the drive shaft 1 to the bottom surface of the large gear 4 wheel seat of the spiral bevel gear pair ; The diameter of the central through hole for the lubrication system pipeline to pass through, which is opened in the center of the large gear 4 of the spiral bevel gear pair , the distance from the hole wall of the positioning piece installation hole closest to the wheel axle center on the large gear 4 wheel seat to twice the distance from the wheel axle centerline , Maximum outer diameter of the 4th wheel seat of the large gear , and the thickness of the large gear 4 wheel seat Among them, the large gear 4 is fixedly driven by its wheel seat and the cam output mechanism 2, not by the transmission shaft, because the lubrication system is installed ( Figure 1 (not shown) and to save space, the pipeline of the lubrication system needs to pass through the center through hole of the large gear 4 and then be connected to the cam output mechanism 2.

[0016] Module of spur gears m and pressure angle α Directly take the module and pressure angle of the replaced spiral bevel gear pair, and the number of teeth of the spur gear z p It can be calculated by Formula 1 described in the content of the invention.

[0017] in, is the tooth top height coefficient of the spur gear, which can be determined by national standards. This can ensure that the spur gear 5 does not interfere with the housing of the multi-arm machine transmission structure, and can also ensure the spur gear hub requirements.

[0018] Tip circle diameter of spur gear 5 d pa Take the outer diameter of the large end of the small bevel gear 3 ; The spur gear will be directly mounted on the existing drive shaft 1, so the diameter of the mounting hole of the spur gear is d n The size is directly taken from the diameter of the drive shaft Other structural parameters can be adjusted according to the structural parameters of the drive shaft, and will not be described in detail in this article. The basic parameters of the spur gear designed in this way have been basically determined, and its appearance dimensions are shown in the following figure. Figure 5 and Figure 7 shown.

[0019] Figure 3 The diagram shows the large gear in the spiral bevel gear pair used in the multi-arm machine. In this embodiment, there are four types of 14 different holes on the circumference of the large gear, which are used to install other accessories on the multi-arm machine. In accordance with the principle of not changing other parts and interfaces of the multi-arm machine except the gears, these holes are retained and their sizes are strictly guaranteed, so it is necessary to retain Figure 3 The wheel seat thickness of the large gear 4 shown in , and the maximum outer diameter of the wheel seat . Maximum outer diameter of the face gear wheel seat D p The number and specifications of the threaded holes on the wheel seat for installation and connection should be consistent with the corresponding parameters of the wheel seat of the large gear of the original spiral bevel gear pair in the multi-arm machine. From this, the wheel seat size used for face gear processing and the size, position, countersunk hole size, etc. on it can be determined to ensure that no bolt is replaced. Therefore, the maximum outer diameter of the wheel seat of face gear 6 can be determined. D p The value is not greater than the maximum outer diameter of the wheel seat of the large gear 4 , the thickness of the wheel seat of the face gear 6 h The value of 1 is not greater than the wheel seat thickness of the large gear 4 .

[0020] Also, see Figure 6 As shown, the outer diameter of the gear teeth of the newly designed face gear is R of Should meet 2 R of < D h ,this D h The distance from the wall of the locating piece installation hole closest to the wheel axle center opened in the face gear wheel seat for installing the locating piece to the wheel axle centerline is twice the distance, so that sufficient installation space can be left on the wheel seat for the above-mentioned threaded installation locating piece to avoid interference between the locating piece and the spur gear 5.

[0021] like Figure 3 and Figure 6 As shown in the figure, the center of the large gear in the spiral bevel gear pair has a diameter of The central functional hole of the face gear wheel seat is used to install other parts. According to the principle of not changing other parts and interfaces of the multi-arm machine except the gear, the diameter of the central functional hole of the face gear wheel seat is d w Should be equal to the diameter of the central functional hole of the large gear , from which the inner diameter of the face gear teeth can be determined R if Should meet 2 R if > d w .

[0022] The gear teeth of the face gear 6 are obtained by gear shaping. The module and pressure angle of the gear shaping cutter correspond to the module of the spur gear. m and pressure angle α， Number of teeth of gear shaping cutter z s Generally, the number of teeth on the spur gear is z p 1 to 3 more teeth are added to ensure that the face gear machined by the gear shaping cutter and the spur gear-face gear transmission formed by the spur gear are in point contact. Therefore, the number of teeth of the gear shaping cutter used to process the face gear can be calculated according to Formula 4 described in the invention.

[0023] Next, we can determine the outer diameter of the face gear teeth. R of and inner diameter R if , respectively calculated by Formula 2 and Formula 3 described in the content of the invention.

[0024] Equation 2 and Equation 3 are implicit functions. and , due to the number of teeth on the gear shaping cutter z s , modulus m , pressure angle α If all are known, the number of teeth of the face gear can be solved z f .

[0025] The number of teeth on the face gear z f This is the initial value, because the face gear will produce root cutting and top cutting during processing, and the root cutting and top cutting are mainly related to the pressure angle of the gear shaping cutter. α、 Tooth ratio of face gear to gear shaping cutter i=z f / z s The number of teeth of the face gear determined by equations 6 and 7 is z f , pressure angle α and modulus m, according to the top cutting and undercutting conditions of the face gear transmission, the corresponding R of，max and R if，min .verify R of and R if Is it reasonable? By adjusting the number of teeth on the face gear z f to make it match.

[0026] The assembly diagram of the spur gear transmission designed in the above manner is as follows: Figure 7 To ensure that the spur gear and the face gear mesh correctly, the height of the boss containing the face gear teeth can be adjusted ( h 2- h 1) Adjust the overall thickness of the face gear h 2 Achieve guaranteed meshing size h 0, this h 0 is also the distance from the axis of the drive shaft 1 to the bottom surface of the face gear wheel seat, ensuring that the gearbox structure and size are not changed. Figure 7 Tooth width Bp and pitch circle radius of spur gears r p or Figure 5 Pitch circle diameter d p The adjustment is not complicated and will not be elaborated in this article.

[0027] Although the embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A design method for a spur-face gear transmission for a high-speed rotary multi-arm machine, characterized in that: The Gleason-tooth spiral bevel gear pair between the driving shaft and the cam output mechanism in the multi-arm machine is replaced with a spur face gear pair, wherein the driving gear connected and driven by the driving shaft is replaced by a spur cylindrical gear from a small bevel gear of the spiral bevel gear pair, and the driven gear connected and driven by the cam output mechanism is replaced by a face gear from a large gear of the spiral bevel gear pair; First measure the following parameters: The shaft diameter of the drive shaft; the maximum outer diameter of the small bevel gear of the spiral bevel gear pair ; Module and pressure angle of spiral bevel gear pair; Then determine the parameters of the spur gear and face gear as follows: Spur gear mounting hole diameter d n Equal to the diameter of the drive shaft; Number of teeth on spur gears z p Calculated by formula 1: Formula 1 in, is the tooth addendum coefficient of the spur gear; d pa is the tooth tip diameter of the spur gear, which is not greater than the maximum outer diameter of the small bevel gear of the spiral bevel gear pair being replaced. ; m is the module of the spur gear, and the module of the spur gear m and pressure angle α The module and pressure angle of the replaced spiral bevel gear pair should be the same; External radius of face gear teeth R of , inner radius R if , Number of teeth z f Calculated by equation 2 and equation 3 respectively: Formula 2 Formula 3 The gear teeth of the face gear are made by gear shaping. m Take the module value corresponding to the spur gear, α Take the pressure angle value corresponding to the spur gear; z s The number of teeth of the gear shaping cutter ， The number of teeth on the spur gear z p The relationship satisfies formula 4: Formula 4 The number of teeth of the gear cutter z s Ratio of spur gear teeth to z p One to three more teeth.

2. The method for designing a spur gear transmission for a high-speed rotary multi-arm machine according to claim 1, characterized in that: In equations 2 and 3, take and , the number of teeth of the gear shaping cutter is known z s , modulus m , pressure angle α , solve for the number of teeth on the face gear z f ;in, The diameter of the central through hole opened in the center of the large gear for the lubrication system pipeline to pass through, It is twice the distance from the hole wall of the locating piece installation hole on the large gear wheel seat that is closest to the wheel axle center to the wheel axle centerline.

3. The method for designing a spur gear transmission for a high-speed rotary multi-arm machine according to claim 1, characterized in that: Maximum outer diameter of the wheel seat of the face gear D p The value is not greater than the maximum outer diameter of the wheel seat of the large gear , the thickness of the wheel seat of the face gear h The value of 1 is not greater than the thickness of the wheel seat of the large gear .

4. The method for designing a spur gear transmission for a high-speed rotary multi-arm machine according to claim 1, characterized in that: The outer diameter of the face gear teeth R of Should meet 2 R of < D h ,this D h The distance from the wall of the locating piece installation hole opened on the face gear wheel seat and closest to the wheel axle center for installing the locating piece to the wheel axle centerline is twice the distance.

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