Study of Tooth Profile Design with Asymmetric Double Circular Arc Gears for Pumps

2010 ◽  
Vol 43 ◽  
pp. 409-413 ◽  
Author(s):  
Yuan Wei Liu ◽  
Jia Fan
Keyword(s):  
Theoretical Foundation ◽  
Tooth Profile ◽  
Design Parameters ◽  
Circular Arc ◽  
The Future ◽  
Gear Pumps ◽  
Profile Design

While transmission theory of asymmetric double circular arc gears is created,the design parameters of asymmetric double circular arc gears are also studied theoretically in this paper. A set of equations for determining asymmetric double circular arc tooth profile are deduced. The theoretical foundation will be laid for designing the gear pumps and reduction boxes in the future productively.

Study on the effects of tooth profile design parameters of rotor to performance of vacuum pump

2020 ◽  
Vol 34 (22n24) ◽  
pp. 2040141
Author(s):  
Van-The Tran ◽  
Bui Trung Thanh ◽  
Banh Tien Long ◽  
Hoang Quoc Tuan ◽  
Duc Toan Nguyen
Keyword(s):  
Vacuum Pump ◽  
Tooth Profile ◽  
Design Parameters ◽  
Tooth Root ◽  
Performance Indices ◽  
Circular Arc ◽  
Numerical Example ◽  
Design Flexibility ◽  
Profile Design ◽  
Rotor Tooth

The vacuum pump usually used traditional curves such as the circular, cycloidal curves and their combinations to construct tooth profile. However, to increase efficiency and design flexibility for the vacuum pump, a novel rotor tooth profile for Roots rotor of vacuum pumps is proposed. Which is named “CEIEC” tooth profile and orderly composed of five significant segments, a circular arc for tooth tip, an epicycloid curve with variable extension, an involute, an enveloped epicycloid curve and a conjugated circular arc for tooth root. A numerical example is presented to evaluate the performance indices for proposed vacuum pump, including the hermeticity coefficients of the rotor mesh gap and tip gap.

Improving the Characteristics of Gear Pumps: Part A — Discharge

2003 ◽  
Author(s):  
Ahmed M. M. El-Bahloul ◽  
Yasser Z. R. Ali
Keyword(s):  
Correction Factor ◽  
Helix Angle ◽  
Tooth Profile ◽  
Radius Of Curvature ◽  
Circular Arc ◽  
Pressure Angle ◽  
Face Width ◽  
Angle Change ◽  
Number Of Teeth ◽  
Gear Pumps

The main objective of this paper is to study the effect of gear geometry on the discharge of gear pumps. We have used gears of circular-arc tooth profile as gear pumps and have compared between these types of gearing and spur, helical gear pumps according to discharge. The chosen module change from 2 to 16 mm, number of teeth change from 8 to 20 teeth, pressure angle change from 10 to 30 deg, face width change from 20 to 120 mm, correction factor change from −1 to 1, helix angle change from 5 to 30 deg, and radii of curvature equal 1.4, 1.5, 2, 2.5, 2.75, and 3m are considered. The authors deduced that the tooth rack profile with radius of curvature equal 2.5, 2.75, 3m for all addendum circular arc tooth and convex-concave tooth profile, and derived equations representing the tooth profile, and calculated the points of intersections between curves of tooth profile. We drive the formulas for the volume of oil between adjacent teeth. Computer program has been prepared to calculate the discharge from the derived formulae with all variables for different types of gear pumps. Curves showing the change of discharge with module, number of teeth, pressure angle, face width, correction factor, helix angle, and radius of curvature are presented. The results show that: 1) The discharge increases with increasing module, number of teeth, positive correction factor, face width and radius of curvature of the tooth. 2) The discharge increases with increasing pressure angle to a certain value and then decreases with increasing pressure angle. 3) The discharge decreases with increasing helix angle. 4) The convex-concave circular-arc gears gives discharge higher than that of alla ddendum circular arc, spur, and helical gear pumps respectively. 5) A curve fitting of the results are done and the following formulae derived for the discharge of involute and circular arc gear pumps respectively: Q=A1bm2z0.895e0.065xe0.0033αe−0.0079βQ=A2bm2z0.91ρ10.669e−0.0047β

Improving the Characteristics of Gear Pumps: Part B — Pressure

2003 ◽  
Author(s):  
Ahmed M. M. El-Bahloul ◽  
Yasser Z. R. Ali
Keyword(s):  
Correction Factor ◽  
Helix Angle ◽  
Tooth Profile ◽  
Radius Of Curvature ◽  
Circular Arc ◽  
Pressure Angle ◽  
Face Width ◽  
Angle Change ◽  
Number Of Teeth ◽  
Gear Pumps

The main objective of this paper is to study the effect of gear geometry on the oil pressure of gear pumps. We have used gears of circular-arc tooth profile as gear pumps and have compared between these types of gearing and spur, helical gear pumps according to pressure. The chosen module change from 2 to 16 mm, number of teeth change from 8 to 20 teeth, pressure angle change from 10 to 30 deg, face width change from 20 to 120 mm, correction factor change from −1 to 1, helix angle change from 5 to 30 deg and radii of curvatures equal 1.4, 1.5, 2, 2.5, 2.75, and 3m are considered. The authors deduced that the tooth rack profile with radius or curvature equal 2.5, 2.75, 3m for all- addendum circular arc tooth and convex-concave tooth profile, and derived equations of pressure difference for spur, helical, and circular- are gear pumps. Computer program has been prepared to calculate the pressure from the derived formulae with all variables for different types of gear pumps. Curves showing the change of pressure with module, number of teeth, pressure angle, face width, correction factor, helix angle, and radius of curvature are presented. The results show that: 1) Pressure increases with increasing helix angle. 2) Pressure decreases with increasing face width, number of teeth, positive correction factor, module, pressure angle and radius of curvature of the tooth. 3) The all- addendum circular-arc gears generates pressure higher than helical, convex-concave and spur gear pumps. 4) A curve fitting is done for all variables with pressure and the following formulae derived for the pressure: P=A3b−0.943z−1.175m−2.1β0.175e−0.61xe−0.0048αP=A4b−1z−1.34m−2β0.119ρ1−0.393 These formulae represent simple tool for the designer to calculate the pressure of involute and circular arc gear pumps.

scholarly journals Dimensionless design approach to translating flat faced follower mechanism with two-circular-arc cam

2019 ◽  
Vol 10 (2) ◽  
pp. 497-503
Author(s):  
Emre Arabaci
Keyword(s):  
Rotation Angle ◽  
Maximum Velocity ◽  
Design Approach ◽  
Design Parameters ◽  
Circular Arc ◽  
Dimensionless Parameters ◽  
Absolute Acceleration ◽  
Cam Profile ◽  
Profile Design ◽  
Critical Characteristics

Abstract. In this study, a dimensionless design approach was presented for translating flat-faced follower mechanism with two-circular-arc cam. Instead of second arc radius (r2), maximum follower lift (smax) and angle of the cam rotation angle (2θmax) variables from the cam profile design parameters were made dimensionless using r2∕r (=λ), smax∕r (=ψ) and θmax∕π (=μ) respectively. Equations for cam profile and follower movement were derived and graphics were obtained depending on the dimensionless parameters. λ and ψ should be in the range [0.0, 1.0], but μ should be in the range [0.0, 0.5]. λ and ψ were changed in the range [0.10, 0.90] and μ in the [0.25, 0.45] range and λ, ψ and μ values were determined for the cam profile. Maximum velocity (vmax), maximum absolute acceleration (amax) and average follower lift (save) changes, which are one of the critical characteristics of follower, were examined for possible cam profiles according to the change of λ, ψ and μ. As a result, vmax and save decreased when μ was increased, vmax and save increased and amax decreased when ψ was increased, amax and save increased when λ was increased.

scholarly journals Experimental and Numerical Study on the Flow Ripple of Circular-arc Gear Pumps Considering the Center Distance Deviation

2021 ◽  
Author(s):  
Xiaoling Wei ◽  
Yongbao Feng ◽  
Zhenxin He ◽  
Ke Liu
Keyword(s):  
Pressure Pulsation ◽  
Numerical Study ◽  
Fluid Dynamic ◽  
Gear Tooth ◽  
Tooth Profile ◽  
Gear Pump ◽  
Circular Arc ◽  
Gear Pumps ◽  
Distance Deviation ◽  
Center Distance

Abstract Novel circular-arc gear pumps effectively solve the problems of oil trapping and flow pulsation experienced with traditional gear pumps. However, the center distance deviation associated with assembly and installation during gear pump processing has an important influence on the outlet pressure pulsation characteristics of circular-arc gear pumps. First, the circular-arc tooth profile equation, conjugate curve equation and meshing line equation were derived to design the circular-arc gear meshing and center distance deviation functions. Second, the circular-arc gear tooth profile was accurately obtained. Then, a pressure pulsation characteristic simulation model for the novel circular-arc gear pumps considering the center distance deviation was established. The results show that with the increase of center distance deviation, the outlet flow rate of the arc gear pump increases first and then decreases greatly. Moreover, the center distance deviation has little effect on the independent tooth cavity pressure. Finally, the proposed fluid dynamic model is used to simulate a commercial circular-arc gear pump, which was tested within this research for modeling validation purposes. The comparisons highlight the validity of the proposed simulation approach.

The Tooth Profile Design and Examination of Circular-Arc Gear Pump

2014 ◽  
Vol 672-674 ◽  
pp. 1604-1607
Author(s):  
Yang Zhou ◽  
Shuang Hui Hao ◽  
Ming Hui Hao
Keyword(s):  
Tooth Profile ◽  
Gear Pump ◽  
Helical Surface ◽  
Circular Arc ◽  
Engagement Theory ◽  
Flow Fluctuations ◽  
Profile Design ◽  
The Mathematical Model ◽  
Gear Engagement ◽  
Examination Process

This paper presents the circular-arc tooth profile that has no trapped-oil feature and flow fluctuations. The mathematical model of tooth profile and helical surface is obtained by gear engagement theory. The examination of helical surface is by coordinate measuring machining (CMM). The sections that perpendicular to the axis direction of gear are selected to obtain the trajectory of measuring ball by the starting points and end points of measuring ball. The examination process of CMM is simulated by Matlab in this paper.

scholarly journals Computer-Aided Design of High-Contact-Ratio Gears for Minimum Dynamic Load and Stress

1993 ◽  
Vol 115 (1) ◽  
pp. 171-178 ◽  
Author(s):  
Hsiang Hsi Lin ◽  
Chinwai Lee ◽  
F. B. Oswald ◽  
D. P. Townsend
Keyword(s):  
Dynamic Load ◽  
Computer Aided Design ◽  
Numerical Procedure ◽  
Tooth Profile ◽  
Lower Sensitivity ◽  
Contact Ratio ◽  
Profile Modification ◽  
Parabolic Profile ◽  
Profile Design ◽  
Optimum Profile

This paper presents a numerical procedure for minimizing dynamic effects on high-contact-ratio gears by modification of the tooth profile. The paper examines and compares both linear and parabolic tooth profile modifications of high-contact-ratio gears under various loading conditions. The effects of the total amount of modification and the length of the modification zone were systematically studied at various loads and speeds to find the optimum profile design for minimizing the dynamic load and the tooth bending stress. Parabolic profile modification is preferred over linear profile modification for high-contact-ratio gears because of its lower sensitivity to manufacturing errors. For parabolic modification a greater amount of modification at the tooth tip and a longer modification zone are required. Design charts are presented for high-contact-ratio gears with various profile modifications operating under a range of loads. A procedure is illustrated for using the charts to find the optimum profile design.

scholarly journals Dynamics Characteristics of Blast Furnace Shell

2011 ◽  
Vol 2-3 ◽  
pp. 1018-1020
Author(s):  
De Chen Zhang ◽  
Yan Ping Sun
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Blast Furnace ◽  
Modal Analysis ◽  
Natural Frequencies ◽  
Theoretical Foundation ◽  
Structural Mechanics ◽  
Mode Shapes ◽  
The Future ◽  
Element Method

Finite element method and structural mechanics method are used to study the blast furnace shell modal analysis and the natural frequencies and mode shapes have been calculated. The two methods were compared and validated , and the results provide a theoretical foundation for the anti-vibration capabilities design of blast furnace shell in the future .

Numerical Efforts of Aerodynamic Re-Design in a Single-Stage Transonic Axial Compressor: Part 1 — Stator Design

2017 ◽  
Author(s):  
Justin (Jongsik) Oh
Keyword(s):  
Pressure Ratio ◽  
Axial Compressor ◽  
Axial Flow ◽  
Single Stage ◽  
Design Flow ◽  
Design Parameters ◽  
Original Design ◽  
Circular Arc ◽  
Surge Margin ◽  
Flow Compressor

In many aerodynamic design parameters for the axial-flow compressor, three variables of tailored blading, blade lean and sweep were considered in the re-design efforts of a transonic single stage which had been designed in 1960’s NASA public domains. As Part 1, the re-design was limited to the stator vane only. For the original MCA (Multiple Circular Arc) blading, which had been applied at all radii, the CDA (Controlled Diffusion Airfoil) blading was introduced at midspan as the first variant, and the endwalls of hub and casing (or tip) were replaced with the DCA (Double Circular Arc) blading for the second variant. Aerodynamic performance was predicted through a series of CFD analysis at design speed, and the best aerodynamic improvement, in terms of pressure ratio/efficiency and operability, was found in the first variant of tailored blading. It was selected as a baseline for the next design efforts with blade lean, sweep and both combined. Among 12 variants, a case of positively and mildly leaned blades was found the most attractive one, relative to the original design, providing benefits of an 1.0% increase of pressure ratio at design flow, an 1.7% increase of efficiency at design flow, a 10.5% increase of the surge margin and a 32.3% increase of the choke margin.

Sign in / Sign up

Export Citation Format

Share Document