JP2973620B2 - Gear tip chamfering method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for chamfering a tooth tip of a bevel gear or hypoid gear having a Gleason-type gradient tooth, which is suitable for chamfering the tooth tip. Things.

[0002]

2. Description of the Related Art In recent years, gears used in automobile speed reducers and the like have been improved in strength by the introduction of shot peening and the like. Therefore, chamfering is often performed on the tooth tips.

However, in the case of a spiral bevel gear or hypoid gear (for example, a ring gear 1 and a pinion 2 shown in FIGS. 5 and 6) having a Gleason type gradient tooth, which is usually used for a final reduction gear for an automobile. Since the tooth height changes along the direction of the tooth trace, it is substantially difficult to perform chamfering on the tooth tip at the same time as gear cutting as in a normal cylindrical gear. For this reason, in the case of chamfering the tip of the spiral bevel gear or hypoid gear (the portions indicated by 1a and 2a in FIG. 7 in the ring gear 1 and the pinion 2), conventionally, in many cases, as shown in FIG. As shown in the drawing, the tooth is processed one by one using a pencil grinder 3 or the like. In recent years, a method has been developed in which the same procedure as that performed manually is automated by moving a small-diameter grindstone along the tooth tip with an NC-controlled tooth tip chamfering machine.

[0004]

However, the former manual processing method has problems that labor costs increase and it is difficult to stabilize the quality. On the other hand, the latter processing method using a tooth tip chamfering machine has problems. In such a case, there is a problem that the cost of machinery and equipment is increased, a complicated program is required, and preparation is troublesome, and the processing time is longer (about 10 seconds per tooth) than in the case of manual work.

[0005]

SUMMARY OF THE INVENTION The present invention relates to a spiral bevel gear or hypoid gear having a Gleason type gradient tooth, the point at which the meshing position changes due to the change in the position of the axes of the gears meshing with each other, and the tooth surface at the time of meshing. An object of the present invention is to provide a method for chamfering the tip of a tooth which advantageously solves the above-mentioned problem in view of the occurrence of slippage in the muscle direction. The method of the present invention provides a method of forming a bevel gear or hypoid gear having a Gleason type gradient tooth. When performing chamfering on the tooth tip portion, abrasive grains are provided on the tooth surface of the tool gear that can mesh with the gear to be chamfered, and the relative positions of the tool gear and the gear to be machined are determined. The present invention is characterized in that the tooth surfaces of the gears are shifted from a position where the tooth surfaces of the gears are in mesh with each other and slidably contact with each other to a position where the tooth surface of the tool gear is meshed with and in contact with the tooth tip of the cut gear, thereby rotating the gears. A. And in this method,
It is more convenient if the tooth width of the tool gear is made longer than the tooth width of the work gear to be meshed.

[0006]

According to the method for chamfering the tooth tip of a gear, abrasive grains are provided on the tooth surface of the tool gear, and the relative positions of the tool gear and the gear to be machined are determined by engaging the tooth surfaces of the gears with each other. Since the tooth surface of the tool gear and the tip of the gear to be machined are shifted from the sliding contact position to the sliding contact position,
Just by rotating the tool gear and the gear to be meshed with each other and rotating the tool gear, the tooth surface on which the abrasive grains of the tool gear are provided is brought into sliding contact with the tooth tip of the gear to be chamfered and chamfered to the tooth tip of the gear to be cut. Since it can be processed, using a device that meshes and rotates the gear, such as a conventional tooth contact inspection device, automatically and extremely quickly chamfers the tooth tip of the gear. Can be.

In the above-mentioned method, if the tooth width of the tool gear is made longer than the tooth width of the gear to be meshed, a chamfering range that easily covers the entire length of the tooth tip of the gear to be cut can be obtained.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIGS. 1 (a) and 1 (b) are cross-sectional views showing an embodiment of a method for chamfering a tip portion of a pinion constituting a hypoid gear as shown in FIGS. 5 and 6 according to the present invention. FIG. 3 is a diagram and a partially enlarged explanatory view, in which a pinion has a Gleason type gradient tooth and is used for a final reducer for an automobile.

In FIG. 1, reference numeral 2 denotes a pinion as a gear to be subjected to chamfering of a tooth tip, and reference numeral 4 denotes a ring gear for grinding as a tool gear which can mesh with the pinion 2. The grinding ring gear 4 is formed substantially in the same manner as a normal ring gear 1 as shown in FIGS. 5 and 6 which is meshed with a pinion 2 to form a hypoid gear. The workpiece is extended and has abrasive particles adhered to at least the tooth surface 4a by an electrodeposition method, so that a work that is in sliding contact with the tooth surface 4a can be ground.

In general, the relative position of a pair of gears of a spiral bevel gear or hypoid gear having Gleason type gradient teeth, for example, the pinion 2 of the pinion 2 with respect to the ring gear 1 shown in FIGS. The pinion mounting distance P (the direction of separation between the ring gear 1 and the pinion 2 is +, and the direction of approach is −), which is the position in the axial direction, and the position of the pinion 2 with respect to the ring gear 1 in the direction perpendicular to the axis. When the offset E (the direction of separation between the ring gear 1 and the pinion 2 is + and the direction of approach is-) is changed, the tooth contact positions of those gears change.

FIG. 2 shows the state of the change in the tooth contact position. The tooth contact position A is as shown in FIG. 2A for the ring gear 1 and as shown in FIG. When the pinion mounting distance P is changed in the + direction, the pinion mounting distance P approaches the tooth tops 1a, 2a. Conversely, when the pinion mounting distance P is changed in the-direction, the pinion mounting distance P approaches the tooth roots 1b, 2b.
When the offset E is changed in the positive or negative direction, the tooth contact position A approaches the side end of the tooth surface.

FIG. 3 shows the pinion mounting distance P such that the tooth contact position A is located at the center of the tooth surface and the offset E by using such properties for each of the ring gear 1 and the pinion 2 forming a pair. FIG. 3 shows a Gleason-type gear tester 5 used to select a suitable shim thickness for the assembly of its mating gear to the gear wheel, so that the gear tester 5 easily changes their pinion mounting distance P and offset E. be able to.

Therefore, according to the working method of this embodiment, the pinion 2 as the above-described gear to be cut is attached to the Gleason-type gear tester 5, and the ring gear 1 is replaced with the ring gear for grinding as the above-mentioned tool gear. 4 is attached to the Gleason-type gear tester 5, and FIG.
As shown in (a), the gears are meshed with each other, and the pinion mounting distance P is set to the tooth tip 2a of the pinion 2 with respect to the tooth surface 4a of the ring gear 4 for grinding.
The tooth contact position A is changed in the negative direction from the value in the normal case where the tooth contact position is located at the center of the tooth surface, and the gears 2 and 4 are rotated in the meshing state.

Due to the rotation in the meshing state,
As shown in FIG. 1 (b), the tip 2a of each tooth of the pinion 2 comes into sliding contact with each tooth surface 4a of the grinding ring gear 4 one after another in the direction of its length, and has a Gleason-type gradient tooth. In the case of the curved bevel gear and the hypoid gear, slippage of the tooth surface in the tooth trace direction occurs at the time of meshing, so that the sliding contact of the tooth tip portion 2a also occurs in the tooth trace direction with respect to each tooth surface 4a of the ring gear 4 for grinding. As a result, the tip 2a of each tooth of the pinion 2 is ground by the abrasive grains of each tooth surface 4a of the ring gear 4 for grinding and chamfered. In addition, since the chamfering process only requires rotating both gears, the time required for the process is as short as about 30 seconds per pinion 2 irrespective of the number of teeth.

Therefore, according to the method of this embodiment, the pinion 2 and the grinding ring gear 4 are simply rotated in a meshed state by using the conventional tooth contact inspection device, and the pinion 2 is rotated.
Can be chamfered on the tip 2a of each tooth, so that the tip 2a of the pinion 2 can be automatically chamfered in a very short time with extremely low equipment cost.

Moreover, in the method of this embodiment, the tooth width of the grinding ring gear 4 is made longer than in the normal case, so that the total length of the tooth tip 2a of the pinion 2 can be maintained even if the pinion mounting distance P is changed. Can be easily obtained.

FIGS. 4 (a) and 4 (b) show another embodiment of the method for chamfering the tip of the present invention which is applied to the chamfering of the tip of a ring key constituting a hypoid gear as shown in FIGS. 5 and 6. It is a cross-sectional view and a partially enlarged explanatory view showing an example, the ring gear here also has Gleason type gradient teeth,
It is used for a final reduction gear for an automobile in combination with the pinion which has been chamfered in the previous embodiment.

In FIG. 4, reference numeral 1 denotes a ring gear as a gear to be subjected to chamfering of a tooth tip, and 6 denotes a grinding pinion as a tool gear that can mesh with the ring gear 1. The grinding pinion 6 is formed substantially in the same manner as a normal pinion 2 as shown in FIGS. 5 and 6 which is meshed with the ring gear 1 to form a hypoid gear. As in the case of the ring gear 4 for grinding, at least its tooth surface 6a
Abrasive grains are adhered to the surface of the workpiece by an electrodeposition method, and a workpiece that is in sliding contact with the tooth surface 6a can be ground.

In the working method of this embodiment, the grinding pinion 6 and the ring gear 1 are attached to the Gleason-type gear tester 5 and the gears are connected to each other as shown in FIG. The tooth contact position A is located at the center of the tooth surface such that the pinion mounting distance P is brought into contact with the tooth surface 1a of the ring gear 1 against the tooth surface 6a of the grinding pinion 6. The value is changed in the positive direction from the value in the normal case, and both gears 2 and 4 are rotated in the meshing state.

Due to the rotation in the meshing state,
As shown in FIG. 4B, the tip 1a of each tooth of the ring gear 1
Is in sliding contact with each tooth surface 6a of the grinding pinion 6 one after another in the direction of its length, and in the case of a curved bevel gear or hypoid gear having Gleason type gradient teeth, slippage occurs in the tooth surface in the tooth surface direction when meshing. Therefore, the sliding contact of the tooth tip 1a also occurs in the tooth trace direction with respect to each tooth surface 6a of the grinding pinion 6,
As a result, the tip 1a of each tooth of the ring gear 1 is ground with the abrasive grains of each tooth surface 6a of the grinding pinion 6 and chamfered. In addition, since the chamfering is only required to rotate the two gears, the time required for the processing is as short as about 30 seconds per ring gear, regardless of the number of teeth, as in the previous embodiment.

Therefore, according to the method of this embodiment, only by rotating the ring gear 1 and the grinding pinion 6 in a meshing state using the conventional tooth contact inspection device, the tooth tip 1a of the ring gear 1 is automatically attached to the tooth tip 1a. Can be chamfered to reduce labor costs and stabilize the quality.Also, it is possible to reduce the cost of machinery and equipment, and eliminate the need for complicated programs to save the labor of preparation. The processing time can be significantly reduced as compared with the case of manual operation.

Further, in the method of this embodiment, the tooth width of the grinding pinion 6 is made longer than in the normal case, so that the total length of the tooth tip 1a of the ring gear 1 can be maintained even if the pinion mounting distance P is changed. Can be easily obtained.

In both of the above embodiments, if the offset E is changed in the + or-direction instead of or together with the pinion mounting distance P, the tooth contact position A is shifted toward the side end of the tooth surface. Since it moves in the direction of the streaks, chamfering of the end face of the gear can be performed automatically in a short time.

Although the present invention has been described based on the illustrated examples, the present invention is not limited to the above-described examples. For example, the above-described work gear and tool gear may be replaced by using a lapping machine instead of the Gleason-type gear tester 5. May be rotated in a meshing state. Further, the present invention can be applied to the chamfering of the tip of a spiral bevel gear having a Gleason-type gradient tooth, and the same operation and effect as the above-described example can be obtained.

[0025]

According to the method of chamfering the tooth tip of the present invention, when chamfering the tooth tip of a spiral bevel gear or hypoid gear having a Gleason type gradient tooth,
Using a conventional gear contact inspection device or other device that meshes and rotates gears, it is only necessary to rotate the tool gear provided with abrasive grains on the tooth surface and the gear to be chamfered by meshing with each other. Since the chamfering can be automatically performed on the tooth tip of the gear to be machined, labor costs can be reduced, quality can be stabilized, and machine equipment costs can be reduced and complex programs can be implemented. Since it is unnecessary, preparation work can be omitted, and the processing time can be significantly reduced as compared with the case of manual operation.

In the above method, if the tooth width of the tool gear is made longer than the tooth width of the gear to be meshed, a chamfering range that easily covers the entire length of the tooth tip of the gear to be cut can be obtained.

[Brief description of the drawings]

FIGS. 1 (a) and 1 (b) are a cross-sectional view and a partially enlarged explanatory view showing an embodiment of a tooth tip chamfering method of the present invention applied to a pinion chamfering processing of a pinion constituting a hypoid gear. It is.

2 (a) and 2 (b) show a pinion mounting distance P and an offset E of a hypoid gear.
FIG. 9 is a partially enlarged explanatory view showing a movement state of a tooth contact position A when changing the position of the ring gear 1 and the pinion 2.

FIG. 3 is a perspective view showing an appearance of a Gleason-type gear tester used for carrying out the method of the embodiment.

FIGS. 4A and 4B are a cross-sectional view and a partially enlarged view showing another embodiment of the tooth tip chamfering method of the present invention applied to the tooth tip chamfering of a ring gear constituting a hypoid gear. FIG.

FIG. 5 is a perspective view showing a ring gear and a pinion constituting a hypoid gear which is a kind of gear to which the present invention can be applied.

FIGS. 6A and 6B are a front view and a sectional view showing a relative positional relationship between a ring gear and a pinion constituting the hypoid gear.

FIGS. 7A and 7B are partially enlarged explanatory views showing positions of tooth tips of a ring gear and a pinion constituting the hypoid gear. FIG.

FIGS. 8A and 8B are explanatory views showing a conventional method of chamfering a tip of a ring gear and a pinion constituting the hypoid gear.

[Explanation of symbols]

 Reference Signs List 1 ring gear 1a tooth tip 2 pinion 2a tooth tip 4 ring gear for grinding 4a tooth surface 5 Gleason-type gear tester 6 grinding pinion 6a tooth surface A tooth contact position E offset P pinion mounting distance

Continuation of front page (58) Field surveyed (Int. Cl. ⁶ , DB name) B23F 1/00-23/12

Claims (2)

(57) [Claims] When a chamfering process is performed on a tip of a spiral bevel gear or hypoid gear having a Gleason type gradient tooth, abrasive grains are formed on a tooth surface of a tool gear that can mesh with a beveled work gear. Are provided, and the relative positions of the tool gear and the machined gear are
Wherein the rotating their gear meshing teeth surfaces of gears from sliding contact position shifted to the tooth surface meshing and the tooth tip portion of the workpiece gear sliding position of the tool gear, the gear Method of chamfering the tooth tip. 2. The tooth width of the tool gear is set to the tooth to be meshed with.
2. The method according to claim 1, wherein the extension is greater than the tooth width of the wheel .