Weddle ring and pinion gears offer the Klingelnberg Palloid System in their manufacturing process, the best available for strength and durability.  This is that you'll want for a long lasting transaxle.

The Klingelnberg Advantage:

Klingelnberg Palloid gears sets are used in many demanding fields of applications, including stationary gearboxes for high tech machinery and in automotive applications where large amounts of torque and shock loading must be delivered through the gearbox and differential section.  This is because the Klingelnberg Palloid design offers some significant advantages that justify the higher productions costs.  Some of these advantages include:

Strength:  Klingelnberg Palloid gears have a parallel slot with, which allows a fully rounded root region with the maximum possible root radii.  This greatly improves resistance to bending stress and tooth fatigue.  The small radius of the lengthwise curvature of the teeth and the high tooth contact ration provided by the unique hobbing motion of this system significantly increases the load carrying capacity of the gear set while the true involute tooth form makes Klingelnberg Palloid gears less sensitive to gearbox and shaft deflections (case flex and shaft flex).  In addition, it is possible to design gears with increased helix angle when necessary for certain applications.  Since it's inception, low sensitivity to deflection and high break-point capabilities have established this method as an effective means of preventing failures in highly stressed gearbox assemblies.  In some applications,  Klingelnberg Palloid gear sets can provide up to 25% more strength in the same size package.

Accuracy:  Teeth are generated purely by rolling motion of the hobs, which insures a high degree of tooth form accuracy.   The generating process is theoretically exact and calculations of the tooth shape is relatively simple compared to the cutter head generated designs.  Even under high volume production conditions, the combinations of continuous indexing and a single-lead hob results in very accurate tooth forms.

Long Gear Life:  The Klingelnberg Palloid method results in extremely smooth running gear sets.  The unique hobbing process provides a slightly scaly surface structure, which provides excellent lapping conditions, provides an oil pocket effect and enhances the inherent smooth rolling motion of the gear teeth.  These features, combined with a high tooth contact ratio, insure a long service life.

Quiet Operation:  A combination of factors, including a high degree of tooth form accuracy, a high tooth contact ratio, and the fact that involute tooth forms are relatively insensitive to deflections and mislocations during final assembly of the gearbox, insure that Klingelnberg Palloid gear sets exhibit extremely good noise behavior, even when conditions are not ideal.

Weddle ring and pinion gears are available for all Mendeola transaxles, including the S4, S4D (11.5" ring gear), S5, S5D (11.5" ring gear), and MD4E.