JPS62816Y2 - - Google Patents

Description

[Detailed explanation of the invention] A. Industrial application field This invention is a throw-away gear cutter,
In particular, the present invention relates to gear cutters that can process several types of gears with different modules with one set of cutters.

B. Prior Art A side milling cutter in which the rough machining area of a gear tooth profile is cut by a plurality of throwaway tips is generally called a rough gear cutter. When machining tooth grooves, this cutter uses cemented carbide for the throw-away tip, which eliminates the need for re-sharpening for most of the machining allowance, increasing machining efficiency and significantly reducing overall man-hours. For example, the one that processes one groove at a time with a single cutter is shown in Tokuko No. 56-14407, and
A patent application filed in 1984 has proposed a device that combines two or more cutters to simultaneously process several tooth grooves on the same module.
Already proposed in No. 141018.

C. Problems to be solved by the invention Among the above, the double-type cutter that simultaneously processes two grooves naturally has double the machining efficiency compared to the one-groove type. Therefore, it is desirable to adopt this double-type cutter to increase productivity, but conventional gear cutters have throw-away tips arranged according to a specific tooth groove shape, and double-type cutters Since the two cutters arranged in parallel were fixed so that the center pitch could not be adjusted, both the single type and double type had the disadvantage that they could only process gears of the same module.

In addition, in conventional cutters of this kind, the accuracy of the cutting edge is ensured by assembly and adjustment, but in many cases the mounting groove of the chip support locator is inclined with respect to the central axis of the cutter. Both the cutter body and locator were difficult to process and assemble, and accuracy control was difficult.

Incidentally, Japanese Utility Model Application Publication No. 50-75191 discloses a cutter that changes the pitch between the blades by replacing the spacer interposed between two gear cutting tools. The following drawbacks can be seen.

In other words, when machining gears using a double type cutter,
The cutter must be positioned so that the center line between the two blades passes through the center of the gear. However,
In the cutter of Utility Model Application No. 50-75191 shown in Fig. 8, the end face 30 of the processing machine is used as the position reference of the gear cutting tools 31, 31', so the thickness of the spacer 32 is adjusted when the gear cutting tool is initially positioned. Measure the collar 35 so that the line O passing through the center is at the center of the workpiece 34.
Needless to say, it is necessary to adjust the width of the spacer, and each time the spacer is replaced, the gear cutting tool must be removed from the drive shaft 36, and the above operation must be repeated to readjust the center position, which may affect the operation of the machine. The loss of work time, which directly leads to a drop in production efficiency, becomes extremely large.

D. Means for solving the problem This invention is a gear cutter that makes it possible to change the pitch between two cutters by replacing the spacer, thereby making it possible to process gears of several types of modules with one set of cutters. The purpose is to make it possible to efficiently change the pitch of the cutter. The present invention is characterized in that this purpose has been achieved by the following configuration.

That is, the gear cutter of this invention has a cylindrical adapter that is divided into a large diameter part and a small diameter part with a reference plane perpendicular to the axis, and a plurality of individual throw-away tips arranged in the tooth groove shape of the maximum machining module. A pair of cutters, one of which is fitted into the small diameter portion of the adapter and the other fitted to the large diameter portion, a first spacer interposed between both cutters, and a spacer between the reference surface of the adapter and one of the cutters. It consists of a second spacer interposed between the blades, a fastening means for fixing one cutter to the adapter, and a fastening means for fixing the two cutters to each other, and it is possible to change the pitch between the blades of the pair of cutters (the pitch between the centers of each cutter). When the increasing pitch is 2M, the first spacer is replaced with a 2M thick spacer, and the second spacer is replaced with a spacer with an increased thickness of M.

In this way, using the reference surface of the adapter as the position reference of the pair of cutters, it is possible to easily perform position adjustment by distributing the increased pitch amount accurately half and half to the left and right of the line, with the center line between the blades as the border. There is no need to readjust the center position of the pair of cutters.

The problem of cutting edge accuracy was solved by devising the locator mounting structure as described later, but this point is not an essential requirement, and therefore in this invention, the conventional locator mounting structure can also be adopted.

E. Embodiments Hereinafter, embodiments of this invention will be described based on the accompanying drawings.

As shown in FIGS. 1 and 4, the gear cutter 1 includes an adapter 2, a large diameter portion 2a, and a small diameter portion 2.
A pair of ring-shaped cutters 10, 1 mounted on b
0', a spacer 3 interposed between both the cutters, a spacer 4 interposed between the reference surface 2c of the adapter formed perpendicular to the axis and one end surface of the cutter 10', and a spacer 3 interposed between the cutters 10' and the cutter 10'. A bolt 5 is used to fix the cutters 10 and 10' to each other, and a bolt 6 is used to fix the cutters 10 and 10' to each other.

Further, on the outer periphery of the cutter 10, throwaway tips A, B, C, D, E, and F are supported by a locator 11 and fixed by a wedge-type presser foot 12.
As shown in FIG. 2, the chips A' and B' are arranged symmetrically about the reference line S within a length l that can cover the cutting area of the largest module. , C′, D′, E′, and F′ are similarly arranged.

Here, the distance W between the cutting edge radius centers of the tip tips A and B, the outer diameter of the gear to be machined, and the tooth pitch are determined, and the inclination angle θ and the cutting edge angle α of the reference line S passing through the center of the tooth groove are determined according to the desired module. range, e.g. 8-14
When machining gears on a module, the area within the module where the machining allowance is the smallest and where machining is stable is selected based on various conditions.

In addition, in the embodiment, two diamond-shaped chips A and B with sharp corners removed at the tips are placed on the rear outer periphery on the left and right sides.
I placed square chips C, D, E, F for individuals,
If the tooth groove shape can be perfectly formed, the shape of the chip,
The arrangement can be freely selected. However, as shown in Figure 3, chips A, B, A', and
By increasing the number of chips B' and arranging the chips 10 and 10' so that they are not lined up in the same phase, the cutting load can be balanced over the entire circumference, and at the same time chips C, D,
It is desirable to unify the lifespan of all cutting edges as much as possible by decreasing the number of effective teeth in the order of decreasing load: C', D'→E, F, E', F'.

The cutters 10, 10' having the above structure have the fourth
As shown in the figure, it is assembled to the adapter 2 via spacers 3 and 4. At this time, if p is the minimum applicable range (minimum module) of the pitch between the centers of the cutter blades determined from the tooth pitch of the gear and the pitch circle diameter, then the thickness h of the spacer 3 and the thickness h ₁ of the spacer 4 are h = h ₁ , and on the other hand, as shown in Fig. 5, when machining a larger module, the center-to-center pitch P'>P corresponds to the spacer 3 set at h' = h + (P' - P ), and spacer 4 is
Use one with a thickness of h ₁ ′=h ₁ +P′−P/2. In other words, when P'-P is 2M, spacer 3 is
2M, spacer 4 is replaced with one with an increased thickness of M.
By doing this, since the distance X from the spindle end face in Figures 4 and 5 is constant, Y is also kept constant, and the center line O of the gear cutter will always face the center of the gear, and the line will be repositioned. It becomes possible to process gears for a range of different modules without having to perform

Note that the reference surface 2c of the adapter is extended to above the center line O, and the spacer fitting groove 13 of the cutter 10 is
By eliminating this, a spacer is not needed when processing the smallest module, and in this case, increasing the module can be handled by setting the thickness of spacer 3 to P'-P and that of spacer 4 to P'-P/2. good.

In addition, considering the workability during assembly/disassembly and internal dust-proofing, it is preferable that the spacers 3 and 4 be in a ring shape extending all the way around the cutter, but the spacers 3 and 4 are preferably ring-shaped, extending only around the outer circumference of the bolt. It is also possible to attach a plurality of shaped pieces at regular intervals in the circumferential direction of the cutter.

Next, the locators 11, 11' adopted in the embodiment
The mounting structure will be explained using one of the cutters shown in FIGS. 6 and 7 as an example.

As shown in the figure, a locator mounting groove 15 is provided on the outer periphery of the cutter body 14, and the positioning reference surface 5a of this groove is aligned with the axis of the cutter, as seen in FIGS. 4 and 5. formed in parallel. The groove 15 also includes the groove 11 on the rear surface of the locator.
A protruding seat surface 15b is provided which fits into the locator a and performs axial positioning and rear support of the locator.

Furthermore, two support pins 16 and 17 whose thickness is adjusted with high precision are interposed between the locator 11 and the reference surface 15a of the groove, and one of the pins 16 is connected to the locator via a double screw 18. 11
The other pins 17 are each fixed to the cutter body 14 via double screws 19. The locator 11 attached to the groove 15 via the support pin is fixed to the cutter body with the screw 20, and is further attached via the tip A attached to the seat surface 11b by the presser foot 12 pulled into the double screw 21. Clamp. However, the presser foot 12 may clamp only the locator, and the tip may be fixed to the locator by other known means, and locators supporting other tips may be similarly fixed.

In the above locator mounting structure, since the reference plane 15a is parallel to the axis of the cutter, the mounting groove and the locator can be precisely machined.
Since the distance H ₁ to the abutting surface and the distance H ₂ from the abutting surface to the tip of the cutting blade can be adjusted to an error of about 0.01 mm, accuracy control becomes easy.

Effects As explained above, this invention supports a pair of cutters arranged in parallel with chips arranged in a range that can cut the tooth groove of the largest module to be machined, using an adapter that has a large diameter part and a small diameter part. Furthermore, a first spacer whose thickness is changed by the same value as the increase in the pitch between the blades is placed between the pair of cutters, and a spacer whose thickness is changed by the same value as the increase in the pitch between the blades is placed between the reference surface of the adapter and one of the cutters. A second spacer whose thickness is changed to 1/2 of the value of I did it like this,
This has the effect of being able to respond to changes in the module with a simple operation of replacing the spacer, which greatly reduces the time required to change the pitch between the blades, thereby increasing the operating rate of the processing machine. .

In addition, gear machining for several types of modules can be performed by simply managing spacers, which is advantageous in terms of tool costs compared to conventional gear cutters. The cutter of this invention is most suitable for machining gears of about 8 to 14 modules, considering the gear module size, blade shape, design constraints, etc.

[Brief explanation of the drawing]

Fig. 1 is a partially omitted end view showing an example of the gear cutter of this invention, Fig. 2 is a diagram showing the radial arrangement of the tips, and Fig. 3 is a schematic diagram showing the circumferential arrangement of the pair of cutters. , FIG. 4 and FIG. 5 are radial sectional views, FIG. 6 is a developed view of the outer periphery of one of the cutters, and FIG. 7 is a sectional view taken along the line X--X in FIG. 6. Moreover, FIG. 8 is a sectional view showing a conventional cutter with variable pitch between cutting tools. 1... Gear cutter, 2... Adapter, 3, 4
...Spacer, 5,6...Bolt, 10,10'
...Katsuta, 11, 11'...Locator, 12...
...Presser foot, 13...Spacer fitting groove, 14...Cutter body, 15, 15'...Locator mounting groove, 16, 17...Support pin, 18, 19...
...double screw, 20...screw, 21...double screw, A, B, C, D, E, F, A', B', C',
D′, E′, F′...chip.

Claims (1)

[Scope of utility model registration request] A cylindrical adapter is divided into a large diameter part and a small diameter part by a reference plane perpendicular to the axis, and a plurality of individual throwaway tips are arranged in the tooth groove shape of the largest processing module, one in the small diameter part of the adapter, A pair of cutters, the other of which is slidably fitted in the large diameter portion in the axial direction, a first spacer interposed between the two cutters, and one of the cutters fitted to the reference surface of the adapter and the small diameter portion. a second spacer interposed between;
It consists of a fastening means for fixing one cutter to the adapter and a fastening means for fixing two cutters to each other, and when changing the pitch between the blades of the pair of cutters, when the increasing pitch is 2M, the first spacer is 2M, A throw-away gear cutter configured to replace the second spacer with one having an increased thickness of M.