JPH02173457A - Protection device of loosen gear-row - Google Patents

Abstract

PURPOSE: To reduce or eliminate a rattle between unloaded gears meshed with each other by making teeth of an extension part of an elastomer slightly oversized relative to gear teeth to occupy a backlash space. CONSTITUTION: In order to overcome a rattle of a gear without a torque load, an extension part 21 of an elastomer is fastened to at least one side of a gear 10, teeth 23 of the extension part 21 is made to have the same profile as teeth 11 of a metallic spur gear 10 but be slightly larger than the teeth 11, and the extension part 21 is overlapped with the teeth 11 by a backlash space. Teeth 13 of a gear 12 is engaged with the large teeth 23 of the extension part 21 though leaving the backlash space from the teeth 11 of the gear 10. Therefore, when the gears are subjected to early oscillatory torque, the large teeth 23 of the extension part 21 eases every impact of the backlash space to prevent a rattle oscillation and a rattle of the gears 10, 12.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a gear train of a manual transmission for a vehicle having a backlash gap between a pair of gears, and eliminates rattling of the gears due to the backlash gap. That's true.

BACKGROUND OF THE INVENTION Optimizing maneuverability and minimizing gear chatter are major challenges in manual transmission design. usually,
A pair of meshing gears has a gap, commonly referred to as a backlash gap, between the meshing teeth due to manufacturing tolerances and dimensions. Angular acceleration of the engine is the primary cause of gear chatter, and that acceleration is periodic in nature. Large inertia of an engine flywheel tends to reduce the magnitude of angular acceleration, whereas a large inertia flywheel reduces vehicle acceleration and slows performance.

Transmissions and drivelines are subject to large angular accelerations, and small vehicle engines tend to have flywheels of small inertia. The load on the auxiliary equipment significantly increases the angular acceleration, and the increase is especially large at idle. Neutral rattle or noise or vibration occurs when the vehicle is stopped, the transmission is in the neutral position, and the clutch is engaged and idle. The periodic angular acceleration applied to the transmission input shaft via the engine causes the spline teeth and gear teeth to collide through the backlash gap, causing rattle. Gear chatter is eliminated by using zero backlash gears and splines. This is achieved with tighter tolerances, but is more difficult and expensive to manufacture, and zero backlash gears generate whine. The meshing of all the gears in a transmission can inherently cause rattle because in the neutral position all the gears are essentially unloaded.

However, meshed gears that are not torqued while the vehicle is in operation are a potential source of rattle. When the engaged gears are transmitting sufficient average or drive torque, no associated rattling occurs. It is clear that in multi-speed manual transmissions, there are meshing gears that are not involved in transmitting more torque than a particular drive gear train, and these unloaded meshing gears can generate chatter.

OBJECTS OF THE INVENTION It is an object of the present invention to reduce or eliminate rattle between unloaded meshing gears.

Another object of the invention is to provide an anti-rattle device that is simple in construction, efficient, economical and easy to assemble and operate.

(Means for Solving the Problems) The present invention provides a gear train rattling prevention device for a pair of meshing gears having a backlash gap therebetween.
an elastomeric extension provided on at least one side of one gear wheel having teeth adapted to mesh with a second gear wheel, said extension being in the form of a flat annular plate fixed to the gear wheel; and having teeth of the same shape and axial alignment as the teeth of the gear, and configured slightly larger in size with respect to the gear teeth so that the teeth of said extension occupy the backlash gap. ing.

(Operation) The present invention relates to a gear train rattling prevention device for a pair of interengaging or meshing gears of a vehicle manual transmission. The device includes an elastomeric extension on one side of at least one of the gears of the pair, the extension having teeth of the same shape as the teeth of the associated gear but slightly larger in size. on the outer periphery. In unloaded conditions, the meshing gears normally engage the elastomeric teeth of the extension to dampen vibrations. When transmitting the average or drive torque, the elastomeric material gradually deforms allowing the metal teeth of both gears to engage.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 shows a pair of meshing gears IO and I2, each having teeth 11 and 13 on its outer periphery and a backlash gap 14 between the gear teeth. Backlash gaps 14 exist due to various manufacturing tolerances and are between gears, which may be any two meshing gears of a multi-speed manual transmission (not shown).

Due to the backlash gap and the torsional vibrations generated in the drive train from the vehicle engine, gear rattling and noise is due to the gear teeth moving through the backlash gap and impacting the mating gear teeth.

To overcome rattling for gears not under torque load, an elastomeric extension 2I (FIG. 2) is attached to at least one side or surface of the gear;
The extension is in the form of an annular ring with teeth 23 on its outer periphery, the teeth having the same shape as the gear teeth 11 of the gear wheel 10 supporting the extension. As shown in FIG. 3, the extension 2I has the same radial dimension as the inner diameter that defines the central opening 24, so that the bearing passing through the gear 11 or I2 is aligned with the central opening 15. ing. In another variant, the side surface 17 of the gear I6 is pressed at 18 to receive an elastomeric extension 3I having a central opening 32 surrounding the shoulder 18 of the gear 16.

The elastomeric extension 2I or 31 is a flat annular plate of material having the characteristics of low absorption (moisture resistance) and high heat distortion temperature to withstand the heat generated in the manual transmission of the vehicle. Suitable elastomers can be heat resistant rubbers or plastics such as nylon, acetal or polyethersulfone. The width of the thickness of the extension is approximately 1, depending on the clearance limits in the transmission and the required deformation of the material.
The preferred thickness of the extension is approximately 3.18 m+n (1/8 inch), although it can range between 59 mm and 6.35 mm.

The extensions 21 and 3I are suitably fixed to the surface of the mating gear 10 or 16 for rotation therewith. Such fixings may be made of a material such as epoxy resin, etc.
．． A suitable adhesive capable of withstanding high temperatures above 9°C (300°F), a spline connection extending through the gear and the extension;
or with a screw or pin extending through an extension into the body of the gear. For spline connections, there may be an axial extension between the gear and the extension, such as heading or swaging the end of the shoulder. If the extension is glued to the gear, an annular body or ring 22 or 23
Only the teeth 23 or 34 are fixed to the gears, and the teeth 23 or 34 are closed at 25 by the application of torque to the meshing gears (Fig. 4).
It is free to transform. As shown in FIG. 5, the surface of the gear 16 in contact with the extension 31 is 19
is cut down to provide a gap for receiving the adhesive 20.

As mentioned above, the teeth 23 or 34 of the extensions 21 and 3I have the same shape as the teeth 11 or 16a of the metal spur gear IO or 16, but the teeth of the extension have a slightly smaller diameter compared to the gear teeth. It's getting bigger. As shown in FIG.
It overlaps the gear teeth with dimensions ranging from 0.002 to 0.007 inches. The average Bankurasonoyu gap is 0.127mm (0,00
5 inches), the amount of overlap is nominally about 0.0025 inches. Thus, when the extension is added to the gear lO, the teeth 13 of the gear 12 are separated from the teeth of the gear 10 by the bathocranule gap 14, but engage the larger sized teeth 23 of the extension 21 (FIG. 3). do. When subjected to initial vibrational torque, the oversized extension teeth cushion any shock in the backlash gap between the gears to prevent rattling and rattling of the gears. The material forming the extension is such that when a predetermined level of threshold average torque is exceeded, the teeth of the extension deform under the torque and the metal teeth of the two gears engage. To be elected.

The teeth of the extension are of a suitable deformable material, where the teeth are solid elastomeric material suitably deformable with respect to the gear teeth. However, if the elastomeric material is hard to prevent excessive surface wear of the extension teeth, the teeth will not absorb torsional vibrations adequately. Figure 7 shows gear tooth 3
7 is shown, each of its teeth having a hole or aperture 38 therethrough to facilitate deformation.

Although the extension is shown on one side of one gear of a pair of meshing gears (FIG. 1), FIG. 6 shows gear 41 having elastomeric extensions 42, 43 on both sides.

This reduces the width of the metal gear or increases the width of the meshing teeth as the meshing gears engage on both extensions. Another possibility, shown in FIG. 8, is that each metal gear 4
adding an elastomeric extension to one side of the meshing gear 46 and the second meshing gear 4 so that the meshing gears 6 and 48 engage the opposite meshing gear 4;
8 by adding an elastomeric extension 49 on the opposite side.

Finally, the pair of spur gears 10 meshing in FIG.
, 12, similar elastomeric extensions can be utilized for the meshing pair of helical or helical gears 51 and 52, as shown in FIG. The elastomeric extension 55 is suitably fixed to the side of one of the two gear wheels 5I or 52. Each gear 5I or 52 has helical teeth 53 or 54, while the extension 55 has helical teeth 5
6, the helical teeth being properly aligned with the teeth of the associated gear, but slightly larger in size as previously mentioned. Also, although a pair of intermeshing gears is described, an elastomeric extension can be added to the surface of the intermediate gear of a three-gear train for reverse manual transmission. All of these variants dampen the gear against oscillating torque and deform when a predetermined level of critical average torque is exceeded.

[Brief explanation of the drawing]

FIG. 1 is a partial sectional view of a pair of meshing gears before application of the present invention, FIG. 2 is a partial perspective view of one of the pair of meshing gears to which a rattling prevention device is attached, and FIG. The figure is a partial cross-sectional view of the gear taken along line 3-3 in Figure 2, Figure 4 is a cross-sectional view similar to Figure 3, but showing a state in which torque is applied to the gear; Figure 5 is a partial cross-sectional view of a modified example of a gear having a rattling prevention device;
Figure 6 is a partial perspective view of a gear with extensions on both sides;
Figure 8 is an enlarged side view of a modified example of gear teeth, Figure 8 is a side view of a pair of gears each having an extension, and Figure 9 is a side view of a pair of meshing helical gears with one gear having an extension. FIG. 10.12 Gear 11, 13: Teeth 16 Gear 21.31: Extension part 36/Extension part
37・Tooth 42.43: Extension part 46.48: Gear 51.52
: Gear 55 Extension part 56 teeth

Claims (1)

[Claims] 1. A gear train rattling prevention device for a pair of meshing gears having a backlash gap therebetween, at least one of the gears having teeth adapted to mesh with a second gear. a tooth with an elastomeric extension provided on the side of the gear, said extension being in the form of a flat annular plate fixed to the gear and having the same shape as and axially aligned with the teeth of the gear; gear train rattle prevention device having a gear train rattle prevention device having a slightly oversized size relative to the gear teeth such that the teeth of said extension occupy the backlash gap. 2. The gear train rattling prevention device of claim 1, wherein the teeth of the extension are not fixed to the gear teeth such that the teeth of the extension deform under a predetermined applied load. 3. The extension part is about 1.6 to 6.4 mm (1/16
3. The gear train anti-rattle device of claim 2, having a thickness in the range of 1/4 inch to 1/4 inch. 4. The gear train anti-rattle device of claim 2, wherein the extension is formed of an elastomeric material having a low coefficient of friction and a high heat deflection temperature. 5. The gear train rattling prevention device of claim 4, wherein the elastomeric material is polyether sulfone. 6. The teeth of the extension part are about 0.5 to 0.18 mm (0.
．． 3. The gear train rattling prevention device of claim 2, wherein the gear train rattling prevention device is increased in size in the range of 0.002 to 0.007 inches. 7. The gear train rattling prevention device of claim 2, wherein each of the teeth of the extension has a lateral hole extending therethrough to enhance the deformability of the tooth. 8. The gear train anti-rattle device of claim 1, wherein the extension is secured to the gear with an adhesive capable of withstanding temperatures of about 300 degrees Fahrenheit. 9. The gear train anti-rattle device of claim 1, wherein an elastomeric extension is secured to each side of the gear. 10. An anti-rattle device for a pair of intermeshing metal gears having gear teeth with a backlash gap therebetween, comprising an elastomeric extension secured to at least one side of at least one of the two gears; An anti-rattle device in which said extension comprises an annular flat body with teeth on its outer periphery having the same shape as, but larger in size than, the teeth of the associated gear. 11. The extension teeth are axially aligned with associated gear teeth to occupy a backlash gap, and the meshing gear teeth initially contact only the extension teeth to resist vibration torques. 11. An anti-rattle device according to claim 10, which provides cushioning. 12. The anti-rattle device of claim 11, wherein the teeth of the extension are deflectable to engage metal gear teeth of meshing gears when a critical average torque is exceeded. 13. The anti-rattle device of claim 11, wherein the elastomeric extension is secured to both sides of one of the gears of the pair. 14. Each of said gears has opposite sides, a first elastomeric extension secured to one side of one of the gears in mesh, and an opposite side of a second gear in mesh; and a second elastomeric extension secured to the anti-rattle device. 15. The anti-rattle device of claim 14, wherein the metal portion of each meshing gear engages an elastomeric extension of the opposite gear. 16. The rattling prevention device according to claim 11, wherein the meshing gears are spur gears. 17. Claim 1, wherein the meshing gears are helical gears, and the extension is provided with matching helical teeth.
The rattling prevention device according to item 1. 18. A method of preventing gear rattling between a pair of meshing gears having a backlash gap between the gear teeth, in which the metal teeth of one gear only engage the teeth of the extension under no load. an elastomeric extension is added to the side of at least one gear to occupy the backlash gap, and the extension is such that the metal teeth of both gears engage when an average torque limit is exceeded; A method that includes a process in which the teeth are deflected.