A gear shaping machine with quick return characteristic transmission system

Abstract

The application discloses a gear shaping machine quick return characteristic transmission system, which comprises a motor, a crank shaft provided with a cutter, a high-efficiency gear pair transmission unit and a non-circular gear transmission unit arranged between the motor and the crank shaft; the high-efficiency gear pair transmission unit is composed of a first driving gear and a second driven gear; the non-circular gear transmission unit comprises a first non-circular gear and a second non-circular gear, and the angle area of the first non-circular gear is in contact with the angle area of the second non-circular gear in sequence; the second driving gear is coaxial with the first non-circular gear, and the second non-circular gear is coaxial with the crank shaft. In the case that the structures and parameters of other parts of the device are not changed, the original transmission parts between the motor and the crank shaft are replaced by the high-efficiency gear pair transmission unit and the non-circular gear transmission unit, so that the cutter return efficiency is doubled under the condition that the cutter cutting state is consistent with the original cutting state, and the overall machining efficiency is significantly improved.

Description

Technical Field

[0001] This invention relates to a transmission system, and more particularly to a gear shaper transmission system with quick-return characteristics. Technical Background

[0002] Currently, see Figure 1 The main cutting motion principle of the gear shaper is still based on the crank-connecting rod-slider mechanism. Slider A connects to the tool B, which reciprocates up and down. When the crankshaft C rotates one revolution, the up-and-down motion of tool B on the workpiece D constitutes one cutting process. From this process, it can be seen that half of the tool's motion generates cutting, while the other half is the return stroke, occupying half of the cutting time. This means that half of the motion is idle, and the return stroke does not generate cutting efficiency, resulting in low overall processing efficiency for the gear shaper. Therefore, improving the processing efficiency of the gear shaper under the same cutting conditions has become an urgent problem for enterprises. Summary of the Invention

[0003] The present invention addresses the shortcomings of the above-mentioned problems by providing a gear shaping machine quick-return transmission system that enables rapid return after tool cutting and is compatible with existing equipment.

[0004] The technical solution to the problem that this invention aims to solve is as follows:

[0005] A gear shaper quick-return transmission system includes a motor and a crankshaft with a cutting tool mounted on it. The system is characterized by further including an efficiency-enhancing gear pair transmission unit and a non-circular gear transmission unit disposed between the motor and the crankshaft.

[0006] The efficiency-enhancing gear pair transmission unit consists of two driving gears, a No. 1 and a driven gear, with a transmission ratio of 5:10 to 1.

[0007] The non-circular gear transmission unit includes a first non-circular gear and a second non-circular gear. The first non-circular gear is divided into four angular regions, β1, β2, β3, and β4, with the mounting shaft as the center. The second non-circular gear is divided into four angular regions, θ1, θ2, θ3, and θ4, with the mounting shaft as the center. The angular regions of the first non-circular gear sequentially contact and transmit power with the angular regions of the second non-circular gear, and β2, β3, and β4 correspond to θ2, θ3, and θ4 as transition meshing sections.

[0008] The No. 2 driving gear is coaxial with the No. 1 non-circular gear, and the No. 2 non-circular gear is coaxial with the crankshaft.

[0009] Preferably, the product of the transmission ratio of the wheel surface corresponding to the β1 angle region of the first non-circular gear and the wheel surface corresponding to the θ1 angle region of the second non-circular gear and the transmission ratio of the efficiency-enhancing gear pair transmission unit is one.

[0010] Preferably, the transmission ratio between the first non-circular gear and the second non-circular gear is 1:1.

[0011] Preferably, the efficiency-enhancing gear pair transmission unit and the non-circular gear transmission unit are fixed to the efficiency-enhancing bracket by bearings.

[0012] The beneficial effects of this invention are as follows:

[0013] Compared with the prior art, under the same cutting conditions, that is, without changing the structure and parameters of other parts of the equipment, the present invention can double the tool return efficiency by replacing the original transmission parts between the motor and the crankshaft with an efficiency-enhancing gear pair transmission unit and a non-circular gear transmission unit, so as to keep the tool cutting state consistent with the original cutting state, thereby significantly improving the overall processing efficiency.

[0014] Compared with existing technologies, this invention can directly modify existing equipment on-site, resulting in low overall equipment upgrade costs, fast upgrade speed, and no need to replace the entire equipment, thus reducing enterprise costs. Attached Figure Description

[0015] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0016] Figure 1 This is a structural schematic diagram of an existing gear hobbing machine;

[0017] Figure 2 This is a schematic diagram of the structural principle of the present invention;

[0018] Figure 3 This is a schematic diagram of the structure of the non-circular gear transmission unit described in this invention;

[0019] Figure 4 This is a schematic diagram of the structure of the non-circular gear transmission unit of the present invention, which sets the gear pitch according to the gear principle;

[0020] Figure 5 This is a schematic diagram illustrating the reasoning results of determining the rationality of the non-circular gear transmission unit profile using the formula of this invention;

[0021] Figure 6 This is a schematic diagram showing the cutting tool and workpiece states during machining of non-circular gear workpieces according to an embodiment of the present invention; Detailed Implementation

[0022] The embodiments of the technical solution of the present invention will now be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, that is, to provide numerous specific details in order to offer a more thorough understanding of the present invention. However, those skilled in the art will recognize that the present invention can be practiced without one or more of these details. In these examples, to avoid confusion with the present invention, some technical features well-known in the art have not been described.

[0023] It should be understood that the present invention can be implemented in different forms and should not be construed as being limited to the embodiments set forth herein. Therefore, these are merely examples and should not be used to limit the scope of protection of the present invention.

[0024] Additionally, it should be noted that, unless otherwise stated, the technical or scientific terms used in this application should have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0025] First, it should be noted that the same cutting conditions in the implementation environment of this invention mean that, apart from the parts between the motor and the crankshaft, the structure and operating parameters of the original equipment remain unchanged.

[0026] See Figure 2 , Figure 3 A gear shaper quick-return transmission system includes a motor 1, a crankshaft 2 with a cutting tool mounted on it, and also includes an efficiency-enhancing gear pair transmission unit 3 and a non-circular gear transmission unit 4 disposed between the motor 1 and the crankshaft 2.

[0027] The efficiency-enhancing gear pair transmission unit consists of at least two driving gears 31 and driven gears 32 with a transmission ratio of 5:10 to 1.

[0028] The non-circular gear transmission unit 4 includes a first non-circular gear 41 and a second non-circular gear 42. The first non-circular gear 41 is divided into four angular regions, β1, β2, β3 and β4, with the mounting shaft as the center. The four angular regions are set with the central axes of β1 and β4 as the lines of symmetry, and the overall outline is elliptical.

[0029] The second non-circular gear is divided into four angular regions θ1, θ2, θ3, and θ4 with the mounting shaft as the center. The angular regions of the first non-circular gear contact and transmit power with the angular regions of the second non-circular gear in sequence. β2, β3, and β4 correspond to θ2, θ3, and θ4 as transition meshing sections. The four angular regions are set with the central axis of θ1 and θ4 as the line of symmetry, and the entire outline is fan-shaped.

[0030] The No. 2 driving gear is coaxial with the No. 1 non-circular gear, and the No. 2 non-circular gear is coaxial with the crankshaft.

[0031] To achieve optimal efficiency, when setting the transmission ratio of the efficiency-enhancing gear pair to increase the crankshaft speed and thus improve efficiency, a transmission ratio of 3:4 is preferred, which can increase the overall efficiency of the gear shaper by 25%. Experimental data shows that when the transmission ratio is close to 1:2, such as 6:10, the efficiency only increases by 40%. The higher the efficiency increase, the less stable the transmission of the subsequent non-circular gear transmission unit 4 becomes.

[0032] In the second non-circular gear 42, θ1 is the rotation angle corresponding to the cutting of the tool during rotation. Typically, θ1 ≥ 120°, and θ1 corresponds to the outer edge of the sector profile, which is the longest segment of the profile surface corresponding to all angles θ of the sector outer profile. On one side of the elliptical major diameter of the first non-circular gear β1 corresponding to θ1, the first non-circular gear 41 and the second non-circular gear 42 need to mesh continuously for transmission.

[0033] In this invention, the efficiency-enhancing gear pair transmission unit plays an efficiency-enhancing role. At the same time, the first non-circular gear 41 and the second non-circular gear 42 are used to restore the original cutting state of the tool, thereby achieving the goal of improving the overall processing efficiency of the gear shaper by only changing the tool return efficiency.

[0034] Furthermore, as an improvement to the present invention, the product of the transmission ratio of the wheel surface corresponding to the β1 angle region of the first non-circular gear and the wheel surface corresponding to the θ1 angle region of the second non-circular gear and the transmission ratio of the efficiency-enhancing gear pair transmission unit is one.

[0035] Furthermore, as an improvement to the present invention, the transmission ratio of the first non-circular gear and the second non-circular gear is 1:1. Furthermore, as an improvement to the present invention, the efficiency-enhancing gear pair transmission unit and the non-circular gear transmission unit are fixed to an efficiency-enhancing bracket by bearings.

[0036] Based on the above improvements, in specific implementation, the standard for establishing the pitch formed by the contact surfaces of the outer contours of the first non-circular gear 41 and the second non-circular gear 42 in the non-circular gear transmission unit 4 is as follows:

[0037] Considering the setting of the non-circular gear transmission unit 4, where the tool moves downward to generate cutting and upward to return, and since the second non-circular gear 42 rotates synchronously with the crankshaft, θ1 in the second non-circular gear 42 is determined to be the cutting angle, and θ2, θ3, and θ4 are the angles where the tool does not participate in cutting and the return angle. Considering the influence of the tool's cutting speed, the cutting angle range of the crankshaft is generally selected to be 120°≤θ1≤180°, and the initial value is taken as: θ1=130° (Note: the angle value of θ1 can also be adjusted according to the needs of later calculations).

[0038] Continue reading Figure 3 The relevant parameters of the first non-circular gear 41 are as follows:

[0039] Appendix Figure 1The crankshaft of the cutting section of the Zhongyuan gear hobbing machine model tool rotates at a constant speed, and in order to ensure... Figure 3 The tool condition in the middle cutting section is restored to Figure 1 Given the cutting state of the cutting tool, the transmission ratio between gear I and gear II at rotation angle β1 is:

[0040]

[0041] The corresponding rotation angle β1 is:

[0042] In the transition curves corresponding to rotation angles β2 and β4, the transmission ratio of non-circular gear 41 (number one) and non-circular gear 42 (number two) is a variable transmission ratio. The transmission ratio is defined to change harmonicly with the rotation angle (the change in transmission ratio is mainly a smooth transition, and any variation curve can be selected). Therefore:

[0043]

[0044]

[0045] Since the transition curves corresponding to rotation angles β2 and β4 are symmetrical curves, and the rotation angle is set to 60°, then:

[0046] β2=β4=60 ②

[0047] 3) Considering both the transition of the variable transmission ratio and ease of calculation, the following settings are made: Figure 3 The transmission ratio corresponding to the rotation angle β3 is a constant transmission ratio. The transmission ratio between the first non-circular gear 41 and the second non-circular gear 42 at rotation angle β3 is set (this transmission ratio actually improves the overall machine efficiency by 25% and doubles the tool return speed):

[0048]

[0049] The corresponding rotation angle β3 is:

[0050] β3 = 360 - β1 - β2 - β4

[0051] Note: i3 and β3 can be arbitrarily set to an initial value and can be adjusted according to the changing shape of the curve in the later stage.

[0052] In addition, please refer to the following during implementation: Figure 4 Furthermore, the meshing joint curve equations for the first circular gear 41 and the second non-circular gear 42 can also be set.

[0053] When the pitch of gear 41 is p, the number of teeth is n, and the center distance is a.

[0054] The pitch curve equation for gear I is as follows:

[0055]

[0056] Where β1+β2+β3+β4=360, and r(β) is the curve radius corresponding to the turning angle β.

[0057] The circumference lengths of the pitch curves corresponding to rotation angles β1, β2, β3, and β4 in gear 41 are calculated as l1, l2, l3, and l4, respectively, as follows:

[0058]

[0059] The pitch curve equation corresponding to the second non-circular gear 42 is as follows:

[0060]

[0061] Since the second non-circular gear 42 and the first circular gear 41 need to be continuously driven, the calculation results need to verify whether the sum of the θ values ​​of each segment in equation ⑥ forms a complete circle, that is:

[0062]

[0063] If the above formula is not valid, the original parameter values ​​set in formulas ①, ②, and ③ need to be adjusted. Since formulas ④ and ⑥ are the meshing joint curve equations of gear 41 (number one circular gear) and gear 42 (number two non-circular gear), and the lengths of each segment of the meshing joint curve in gear 42 (number two non-circular gear) are consistent with the lengths of each segment in formula ⑤ of gear 41 (number one circular gear), the relevant calculations and comparisons of the lengths of each segment of the joint curve in gear 42 (number two non-circular gear) are no longer required.

[0064] Continue reading Figure 5 Based on the magnitude of the machine tool's transmission torque and the size of the crankshaft, we currently set a = 200 and substitute it into the above formula to perform relevant calculations, resulting in the relevant graph of the pitch curve, as shown below. Figure 5 As shown:

[0065] Figure 5 As can be seen from (I), the meshing curve of the second non-circular gear 42 is discontinuous, indicating that the previously set parameters are unreasonable. The set parameters for the first circular gear 41 and the second non-circular gear 42 need to be corrected for reasonableness.

[0066] By changing the angle θ1 in equation ① and correcting it according to formula ⑦, we obtain... Figure 5 (II) Since θ1 is the cutting angle of the gear shaper, the angle is usually θ1≥120 degrees. Changing only θ1 cannot meet the angle requirements of the cutting section of the gear shaper.

[0067] By changing the transition angles β2 and β4 in equation ② and correcting them according to equation ⑦, we obtain... Figure 5 (III) The transmission ratio of the meshing curve in the transition section changes significantly, which is not conducive to the smooth transmission of the main motion mechanism of the gear hobbing machine. Therefore, it is not recommended to reduce the angle of the transition curve.

[0068] Then, by changing the transition transmission ratio i3 in equation ③ and correcting it according to equation ⑦, we obtain... Figure 5 (IV) It can be seen that changing the transition ratio i3 is more reasonable.

[0069] Continue reading Figure 6 After obtaining the above curve equations and related parameters, a gear shaper is used to machine the first spur gear 41 and the second non-spur gear 42. This embodiment focuses on the machining of the first spur gear 41; this method can be extrapolated to the machining of the second non-spur gear 42 and other non-spur gears. Considering the magnitude of the torque transmitted by the machine tool itself, a gear pitch p = 18 is set for preliminary calculations, based on gear principles as follows... Figure 4 have:

[0070] l1 + l2 + l3 + l4 = n * p (where n is an integer)

[0071] According to formula ⑤:

[0072] l1 + l2 + l3 + l4 = 626.5634

[0073] The result is: n = 34.8091

[0074] Let n = 34,

[0075] Then the gear pitch p = 1842834

[0076] Then the gear module

[0077] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention.

Claims

1. A shaving machine quick return characteristic drive system comprising a motor, a crank shaft having a cutter mounted thereon, characterized in that: The efficiency-boosting gear pair transmission unit and the non-circular gear transmission unit are arranged between the motor and the crankshaft. The efficiency-boosting gear pair transmission unit is composed of a first driving gear and a second driven gear, and the transmission ratio of the first driving gear to the second driven gear is 5:10-1. The non-circular gear transmission unit comprises a first non-circular gear and a second non-circular gear, the first non-circular gear is divided into four angle regions of β1, β2, β3 and β4 with a mounting shaft as the center, the second non-circular gear is divided into four angle regions of θ1, θ2, θ3 and θ4 with the mounting shaft as the center, the angle regions of the first non-circular gear are in contact with the angle regions of the second non-circular gear in sequence, β1 and θ1 correspond to a cutting section, β3 and θ3 correspond to a quick-return section, β2 and θ2, and β4 and θ4 are transition meshing sections, and the transmission ratio of the quick-return section is greater than that of the cutting section. The second driving gear is coaxial with the first non-circular gear, and the second non-circular gear is coaxial with the crankshaft. The transmission ratio of the wheel surface corresponding to the β1 angle region of the first non-circular gear to the wheel surface corresponding to the θ1 angle region of the second non-circular gear is 1. The transmission ratio of the first non-circular gear to the second non-circular gear is 1:

1.

2. A quick return characteristic transmission system for a gear shaping machine according to claim 1, characterized in that: The efficiency-boosting gear pair transmission unit and the non-circular gear transmission unit are fixed on the efficiency-boosting support by bearings.

3. The quick return characteristic transmission system of a gear shaping machine according to claim 1, characterized in that: ​

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