Gear shape of large gear of high-efficiency low-pulsation chemical internal gear pump

Abstract

The present invention discloses a tooth profile of a large gear of an efficient and low-pulsation chemical internal gear pump. The internal gear pump includes a large gear and a small gear that mesh with each other. The large gear has an arc tooth profile. There are 13 teeth evenly arranged inside the large gear. Each tooth includes a tooth tip, a tooth root, and a tooth profile that meshes with the small gear. The tooth profile is a convex arc shape. The outer diameter of the large gear is Rf, the inner diameter of the large gear is Rr, the tooth profile radius of the large gear is Rc, and the center radius of the large gear tooth profile is Rw. Among them, 2 < Rc / Rf < 2.5 and 2.3 < Rw / Rf < 3. There are four teeth included in the circle where the large gear tooth profile is located. By changing the tooth number ratio of the traditional large and small gears from 9 to 7 to 13 to 10, the tooth number and the multiple frequency are greatly increased, and the noise and vibration of the internal gear pump are greatly reduced. By changing the values of Rc and Rw, that is, 2 < Rc / Rf < 2.5 and 2.3 < Rw / Rf < 3, and there are four teeth included in the circle where the large gear tooth profile is located, the contact ratio of the internal gear pump is improved, so that the contact ratio is greatly increased, meeting the industry standard of gear transmission.

Description

Technical Field

[0001] This invention relates to the field of positive displacement internal gear pump tooth profile technology, and more particularly to the tooth profile of the large gear of a high-efficiency, low-pulsation chemical internal gear pump. Background Technology

[0002] In 1911, Jens Nielsen, a Danish-American, and three immigrant partners founded a company in Denmark. In 1915, Jens Nielsen invented the internal gear pump. The internal gear pump uses the principle of internal gear meshing. The pitch circles of the inner and outer gears are close together on one side, while the other side is separated by a crescent plate on the pump cover. The driving inner gear on the main shaft drives the inner and outer gears to rotate in the same direction. At the inlet, the gears separate to create a negative pressure, drawing in liquid. At the outlet, the gears continuously engage and mesh, squeezing the liquid out.

[0003] In 1921, he licensed the pump to a Danish company, which was sold worldwide under the name Rotan (metric). Later, Jens Nielsen returned to the United States and founded a new brand, Viking (imperial). Therefore, Viking and Rotan's internal gear pump technology originated from the same source, but they became two separate brands. For over 100 years, countries around the world have been imitating the core technology of the Danish-American Jens Nielsen, and this has remained fundamentally unchanged.

[0004] Jens Nielsen's internal gear pumps, especially those with small diameters (DN80 and below), all employ a 9-pair, 7-tooth design. This design is widely used in the chemical industry due to its simple manufacturing process, high tooth height, small size, large displacement, and wide range of pumpable media. However, its outdated technology, very low overlap, large pulsation, high noise, and high vibration make it unsuitable for demanding environments. Industry leaders Rotan and Viking recognized these shortcomings, and both considered minimizing costs to resolve them without altering the installation dimensions and displacement of the gears. However, they spent considerable time, manpower, and money without achieving a satisfactory solution.

[0005] Therefore, the shortcomings of internal gear pumps, such as very low overlap, large pulsation, high noise, and high vibration, make them unsuitable for high-requirement environments. This is a pain point for the entire industry and also the biggest core technical challenge. Summary of the Invention

[0006] In view of the problems in the related art, the present invention discloses a tooth profile of a large gear of an efficient and low-pulsation chemical internal gear pump, which solves the problems raised in the above-mentioned background art without changing the original pump installation dimensions and interchange requirements, improves the contact ratio of the chemical internal gear pump, and greatly reduces the pulsation, noise and vibration of the internal gear pump, thereby solving the technical pain points and difficulties of the industry from the core technology.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A tooth profile of a large gear of an efficient and low-pulsation chemical internal gear pump, the internal gear pump includes a large gear and a small gear, the large gear is an internal gear, the small gear is an external gear, the small gear is meshed inside the large gear, the large gear is an arc tooth profile, 13 teeth are evenly arranged inside the large gear, each tooth includes a tooth tip, a tooth root and a tooth profile meshing with the small gear, the radius of the circle where the tooth root of the large gear is located, that is, the outer diameter of the large gear, is Rf, the radius of the circle where the tooth tip of the large gear is located, that is, the inner diameter of the large gear, is Rr, the radius of the circle where the tooth profile of the large gear is located, that is, the tooth profile radius of the large gear, is Rc, the circle where the tooth root of the large gear is located is concentric with the circle where the tooth tip of the large gear is located, and the distance between the center of the circle where the tooth profile of the large gear is located and the center of the circle where the tooth root of the large gear is located, that is, the tooth profile center radius of the large gear, is Rw. Among them, 2 < Rc / Rf < 2.5 and 2.3 < Rw / Rf < 3.

[0009] As a further scheme of the present invention: the tooth profile is a convex arc shape.

[0010] As a further scheme of the present invention: there are four teeth inside the circle where the tooth profile of the large gear is located.

[0011] As a further scheme of the present invention: the circle where the tooth profile of the large gear is located coincides with the tooth profile line of the outermost tooth it contains.

[0012] As a further scheme of the present invention: the number of teeth of the small gear paired and conjugated with the large gear is 10.

[0013] As a further scheme of the present invention: the gear modulus of the large gear is 2 / 3 of the traditional 9-to-7 gear modulus. Considering data rounding, the error meets ±10%.

[0014] As a further scheme of the present invention: the value of Rw is greater than the value of Rc.

[0015] As a further scheme of the present invention: Rf = 45mm, Rw = 118.75mm, Rc = 97.6mm.

[0016] Compared with the prior art, the beneficial effects of the present invention are:

[0017] Tooth profile of the large gear of a high-efficiency and low-pulsation chemical internal gear pump. The internal gear pump includes a large gear and a small gear that meshes with each other. The large gear has an arc tooth profile, and the inside of the large gear has 13 teeth evenly arranged. Each tooth includes a tooth tip, a tooth root, and a tooth profile that meshes with the small gear. The tooth profile is a convex arc. The outer diameter of the large gear is Rf, the inner diameter is Rr, the radius of the tooth profile of the large gear is Rc, and the center radius of the tooth profile of the large gear is Rw. Among them, 2 < Rc / Rf < 2.5 and 2.3 < Rw / Rf < 3. The circle where the tooth profile of the large gear is located includes four teeth.

[0018] By changing the tooth number ratio of the traditional large and small gears from 9 to 7 to 13 to 10, the tooth number and the multiple frequency are greatly increased, and the noise and vibration of the internal gear pump are greatly reduced. By changing the values of Rc and Rw, that is, 2 < Rc / Rf < 2.5 and 2.3 < Rw / Rf < 3, and the circle where the tooth profile of the large gear is located includes four teeth, the contact ratio of the internal gear pump is improved, so that the contact ratio is greatly increased, meeting the gear transmission industry standard.

[0019] Through the above improvements, a significant reduction in the pulsation, noise, and vibration of the chemical internal gear pump is achieved, and the efficiency of the internal gear pump is improved. Brief Description of the Drawings

[0020] The drawings are used to provide a further understanding of the present invention and constitute a part of the specification. They are used together with the embodiments of the present invention to explain the present invention and do not constitute a limitation to the present invention.

[0021] In the drawings:

[0022] Figure 1 It is a schematic diagram of the tooth profile structure and code of the large gear of a high-efficiency and low-pulsation chemical internal gear pump according to the present invention.

[0023] Figure 2 It is a drawing of the dimension code of the large gear of Rotan 41 (metric).

[0024] Figure 3 It is a drawing of the dimension code of the large gear of Viking HL (imperial).

[0025] Figure 4 It is a drawing of the dimension code of the large gear according to the present invention.

[0026] Annotation of the reference numerals in the drawings:

[0027] 1. Tooth tip; 2. Tooth profile; 3. Tooth root; β. Meshing angle; Detailed Description of the Embodiment

[0028] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatuses and methods consistent with some aspects disclosed in this embodiment as detailed in the appended claims.

[0029] It should be noted that all directional indicators in the embodiments (such as up, down, left, right, front, back, etc.) are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0030] Furthermore, descriptions using terms such as "first" and "second" in the embodiments are for descriptive purposes only and do not specifically refer to any order or sequence, nor are they intended to limit the invention. They are merely used to distinguish components or operations described using the same technical terms and should not be construed as indicating or implying their relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but only if they are feasible for those skilled in the art. If a combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination does not exist and is not within the scope of protection claimed by this invention.

[0031] To further understand the content, features, and effects of this invention, the following embodiments are provided, and detailed descriptions are given below in conjunction with the accompanying drawings:

[0032] like Figure 1-4 As shown:

[0033] First, referencing the globally renowned brands Viking and Rotan, which use 9 pairs of 7 teeth for their large and small gears, we compare the main parameters of the large gear when designing for a DN40 diameter (other diameters are similar and will not be explained further).

[0034] Comparison Table 1

[0035]

[0036]

[0037] As can be seen from the above comparison examples, the globally well-known brands Viking and Rotan are similar in the design of the main parameters of the large gear with 9 pairs of 7 teeth, inheriting the concept of the original inventor. However, today, 100 years later, the gear transmission industry has high requirements for the life, vibration, and noise of gears, and the industry standard is that the contact ratio is greater than 1.2. Therefore, this standard can also be promoted in the chemical internal gear pump industry to improve the technical standards of the industry and solve the problems mentioned above.

[0038] In order to improve the contact ratio of the internal gear pump, the present invention proposes the following technical solutions:

[0039] As Figure 1 shown, the tooth profile of the large gear of the high-efficiency and low-pulsation chemical internal gear pump. The internal gear pump includes a large gear and a small gear. The large gear is an internal gear, and the small gear is an external gear. The small gear meshes inside the large gear, and the large gear has an arc tooth profile.

[0040] The large gear is evenly provided with 13 teeth inside, and the number of teeth of the small gear paired and conjugated with the large gear is 10. In order to keep the center distance between the large and small gears unchanged (that is, the installation position of the small gear remains unchanged), the gear modulus of 13 pairs of 10 is 2 / 3 of the traditional gear modulus of 9 pairs of 7. Considering data rounding, the error meets ±10%.

[0041] Each tooth includes a tooth tip 1, a tooth root 3, and a tooth profile 2 meshing with the small gear. The tooth profile is a convex arc.

[0042] The radius of the circle where the tooth root 3 of the large gear is located, that is, the outer diameter of the large gear, is Rf. The radius of the circle where the tooth tip 1 of the large gear is located, that is, the inner diameter of the large gear, is Rr. The radius of the circle where the tooth profile 2 of the large gear is located, that is, the radius of the tooth profile 2 of the large gear, is Rc. The circle where the tooth root 3 of the large gear is located is concentric with the circle where the tooth tip 1 of the large gear is located. The distance between the center of the circle where the tooth profile 2 of the large gear is located and the center of the circle where the tooth root 3 of the large gear is located, that is, the center radius of the tooth profile of the large gear, is Rw. Among them, 2 < Rc / Rf < 2.5 and 2.3 < Rw / Rf < 3, and the value of Rw is greater than the value of Rc.

[0043] The circle where the tooth profile 2 of the large gear is located includes four teeth, and the circle where the tooth profile 2 of the large gear is located coincides with the tooth profile line of the outermost tooth it contains.

[0044] Preferably, as Figure 4 shown, Rf = 45mm, Rw = 118.75mm, Rc = 97.6mm.

[0045] Comparison Table II

[0046]

[0047]

[0048] It can be seen from the above Comparison Table II that:

[0049] 1. In order not to change the installation dimensions of the large gear, that is, the outer diameter of the large gear Rf = 45 remains unchanged.

[0050] 2. By changing the tooth ratio of the traditional large and small gears from 9 to 7 to 13 to 10, the multiple frequency increases from 9x7 = 63 to 13X10 = 130, greatly increasing the number of teeth and the multiple frequency, and reducing noise and vibration.

[0051] 3. Make the circle of the large gear tooth profile radius Rc change from including 2 teeth to 4 teeth.

[0052] 4. By changing the values of the large gear tooth profile radius Rc and the large gear tooth profile center radius Rw, satisfying 2 < Rc / Rf < 2.5 and 2.3 < Rw / Rf < 3, the contact ratio can be increased from 0.53 to 1.27.

[0053] 5. In order to keep the center distance of the large and small gears unchanged, the module of the 13-to-10 gear is 2 / 3 of the traditional 9-to-7. Considering data rounding, the error satisfies ±10%.

[0054] In this way, by increasing the number of teeth and changing the number of tooth pairs, without changing the installation dimensions, the multiple frequency is greatly increased by 2 times, and the contact ratio is increased from 0.53 to 1.27, thus achieving a significant increase in the contact ratio and meeting the industry standards of gear transmission.

[0055] Through the above, the pulsation, noise and vibration of the chemical internal gear pump are greatly reduced, and the efficiency of the pump is improved.

[0056] Finally, it should be noted that the above disclosure is only the preferred embodiment of the present invention and is not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features. Any modification, equivalent replacement, ratio scaling, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention. The scope of this application is only limited by the appended claims.

Claims

1. A high efficiency low pulsation chemical internal gear pump gear, the internal gear pump comprising a gear and a pinion, the gear is an internal gear, the pinion is an external gear, the gear is internally engaged with the pinion, the gear is a circular arc tooth profile, characterized in that: The large gear has 13 teeth evenly arranged inside. Each tooth includes a tooth tip (1), a tooth root (3), and a tooth profile (2) that meshes with the small gear. The radius of the circle where the tooth root (3) is located is the outer diameter of the large gear, which is Rf. The radius of the circle where the tooth tip (1) is located is the inner diameter of the large gear, which is Rr. The radius of the circle where the tooth profile (2) is located is the tooth profile radius of the large gear, which is Rc. The circle where the tooth root (3) is located is concentric with the circle where the tooth tip (1) is located. The distance between the center of the circle where the tooth profile (2) is located and the center of the circle where the tooth root (3) is located is the center radius of the tooth profile, which is Rw. Wherein, 2 < Rc / Rf < 2.5 and 2.3 < Rw / Rf < 3. The circle where the tooth profile (2) is located includes four teeth. ​ 2. The high efficiency low pulsation chemical internal gear pump gear wheel according to claim 1, characterized in that: The tooth profile (2) is convex arc-shaped.

3. The high efficiency low pulsation chemical process internal gear pump gear wheel of claim 1, wherein: The circle containing the tooth profile (2) of the large gear coincides with the tooth profile line of the outermost tooth.

4. The high efficiency low pulsation chemical process internal gear pump gear wheel of claim 1, wherein: The large gear is paired with a conjugate pinion with 10 teeth.

5. The high efficiency low pulsation chemical process internal gear pump gear wheel of claim 3, wherein: The gear module of the large gear is 2 / 3 of the traditional 9-to-7 gear module. Considering data rounding, the error meets ±10%.

6. A high efficiency low pulsation chemical process internal gear pump gear wheel as claimed in claim 1 wherein: The Rw value is greater than the Rc value.

7. The large gear of a high-efficiency, low-pulsation chemical internal gear pump according to claim 1, characterized in that: Rf=45mm, Rw=118.75mm, Rc=97.6mm.

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