CN202845951U - Tool for machining hole bottom reverse chamfering - Google Patents

Abstract

The utility model provides a tool for machining reverse chamfering at the bottom of a hole. The tool includes a tool handle integrally connected, a tool bar, a cutting head, an eccentric sleeve sleeved on the outer side of the tool handle, and a hard tool integrally connected with the cutting head. High-quality alloy blades, the tool holder, tool bar and cutting head rotate synchronously with zero eccentricity, and there is an adjustable eccentricity e between the cutting head and the eccentric sleeve, which meets the

, where D is the diameter of the inner hole of the reverse chamfer, d is the diameter of the edge of the cutting head with the alloy blade, h is the height of the reverse chamfer, and α is the angle of the reverse chamfer. The development of the tool of the utility model can design eccentric sleeves with different eccentricities according to the diameter of the inner hole of the workpiece, and use the eccentricity and NC program control to automatically process the reverse chamfers of different diameters on the CNC with high precision and high efficiency.

Description

Tools for chamfering the bottom of holes

technical field

The utility model relates to a metal cutting tool, in particular to a cutting tool used for machining reverse chamfering of the hole bottom of a metal workpiece.

Background technique

In conventional metal workpiece processing, it is more convenient to process the front chamfering of the inner hole. You can use an angled chamfering knife on the machine tool, or scrape it with a scraper by hand. However, it is much more difficult to process the reverse chamfering of the inner hole. For the reverse chamfering of the inner hole of the processed parts, it is traditionally scraped with a manual scraper, or chamfered with a special chamferer for small hardware. This is not only inefficient, but also easy to scratch the workpiece. As shown in Figure 1, it is a structural cross-sectional view of a workpiece to be processed. In the illustration, the workpiece 1 has two upper and lower inner holes 11 and 12 that are transparent to the inner cavity. The rib wall is very close to L, and when the chamfering 111 and 112 are highly required, the special chamfering device for hardware cannot be stretched, and the scraper cannot go deep. Especially when the hole is deep, it is difficult to guarantee the tool strength.

Contents of the invention

The utility model discloses a high-strength eccentric sleeve type cemented carbide hole bottom reverse chamfering tool, which is aimed at the inner holes of some precision parts requiring reverse chamfering, especially when there are higher requirements for the angle and depth of the chamfering , It can also solve the problem of reverse chamfering when the distance between the end face of some parts that needs to be chamfered and the inner rib wall is very close.

，其中D为反倒角内孔的直径，d为切削头带合金刀片刀刃处的直径，h是反倒角的高度、α为反倒角的角度。 The technical solution of the utility model to achieve the above purpose is: a tool for machining reverse chamfering at the bottom of a hole, characterized in that the tool includes a tool handle, a tool bar, a cutting head that are integrally connected, and a tool that is sleeved on the tool handle The eccentric sleeve on the outside, the cemented carbide blade integrally connected with the cutting head, the shank, the shank and the cutting head have zero eccentricity, and there is an adjustable eccentricity e between the cutting head and the eccentric sleeve, which satisfies

, where D is the diameter of the inner hole of the reverse chamfer, d is the diameter of the edge of the cutting head with the alloy blade, h is the height of the reverse chamfer, and α is the angle of the reverse chamfer.

Further, the eccentric sleeve includes an M-type eccentric sleeve with an eccentric range of 1.5-5 mm and an N-type eccentric sleeve with an eccentric range of 5-17 mm.

Further, the cutter rod is a quenched steel rod body with an olive-shaped section.

Further, the eccentric sleeve is provided with a sleeve hole with an eccentric e, the handle of the knife is slipped into the sleeve hole, and the handle of the knife is fastened in the sleeve hole by a grub screw penetrating the eccentric sleeve.

Further, the side of the eccentric sleeve facing the cutting head is provided with a position marking line.

After applying the technical solution of the utility model, its remarkable technical effect is embodied as follows: the cutting tool can design eccentric sleeves with different eccentricities according to the diameter of the inner hole of the workpiece, and use eccentricity and NC program control to achieve high-precision, Efficient and automatic processing of reverse chamfers of different apertures improves the flexibility and precision of metal cutting tools for special applications.

The specific implementation of the utility model will be described in further detail below in conjunction with the accompanying drawings of the embodiments, so as to make the technical solution of the utility model easier to understand and grasp.

Description of drawings

Fig. 1 is a structural sectional view of a workpiece to be processed.

Fig. 2 is a schematic diagram of the integrated structure of the utility model tool handle, tool bar and cutting head.

Fig. 3 is a structural schematic diagram of an M-type eccentric sleeve of the present invention.

Fig. 4 is a structural schematic diagram of an N-type eccentric sleeve of the present invention.

Fig. 5 is a schematic diagram of the working state of the utility model tool for machining reverse chamfering.

Detailed ways

The utility model discloses a high-strength eccentric sleeve type cemented carbide hole bottom reverse chamfering tool, which is aimed at the inner holes of some precision parts requiring reverse chamfering, especially when there are higher requirements on the angle and depth of the chamfering , It can also solve the reverse chamfering when the end face of some parts that needs to be chamfered is very close to the inner rib wall.

，其中D为反倒角内孔的直径，d为切削头带合金刀片刀刃处的直径，h是反倒角的高度、α为反倒角的角度。无特别要求时，可简化公式计算：

。 As shown in Fig. 2 to Fig. 4, this kind of cutting tool for processing the reverse chamfering of the bottom of the hole, the integrally connected tool handle 21, tool bar 22, cutting head 23, and the eccentric sleeve sleeved on the outside of the tool handle, and the cutting head 23 integrally connected hard alloy blades 24. Wherein the tool handle 21, tool bar 22 and cutting head 23 have zero eccentricity, and there is an adjustable eccentricity e between the cutting head 23 and the eccentric sleeve, which satisfies

, where D is the diameter of the inner hole of the reverse chamfer, d is the diameter of the edge of the cutting head with the alloy blade, h is the height of the reverse chamfer, and α is the angle of the reverse chamfer. When there is no special requirement, the formula calculation can be simplified:

.

The tool body consisting of tool handle, tool bar and cutting head needs to be quenched to HRC50, and the eccentric sleeve is quenched to HRC48. The cemented carbide blade is brazed on the cutting head, and the welding is firm without cracks. The material of the cemented carbide is selected according to the parts to be processed, such as YG6X, YL10.2, YT14, etc. According to the difference in eccentric value, eccentric sleeves are divided into M-type eccentric sleeves with an eccentric range of 1.5-5mm (as shown in Figure 3) and N-type eccentric sleeves with an eccentric range of 5-17mm (as shown in Figure 4) . As can be seen in FIG. 3 , the M-shaped eccentric sleeve 31 has an eccentric sleeve hole 311 , and a perforation is provided through the eccentric sleeve. As shown in FIG. 4 , it can be seen that the N-type eccentric sleeve 32 has an eccentric sleeve hole 321 , and a perforation is provided through the eccentric sleeve. The knife handle is slippery matched with the sleeve hole, and the knife handle is fastened in the sleeve hole by the grub screw penetrating the eccentric sleeve. The above-mentioned perforation is used for the grub screw to penetrate and press to lock the handle. It should be noted that the above-mentioned so-called eccentricity e refers to the distance deviation between the center line of the spindle of the machining center and the center line of the hole set by the eccentric sleeve, and there is zero eccentricity between the center line of the hole and the tool body.

In particular, the above-mentioned knife rod 22 is a hardened steel rod body with an olive-shaped section. The length of the tool bar should be slightly longer than the depth of the inner hole to be chamfered, and its section is olive-shaped. The olive-shaped section is formed by the intersection of two identical arcs, and its radius is slightly smaller than the radius of the cutting head with alloy blade.

When the tool of the utility model is working: firstly, programming is required to fix the CNC spindle at a specific position when it stops rotating. Then select the appropriate eccentric sleeve according to the diameter of the inner hole and the specifications of the reverse chamfer to be processed. And the handle of a knife is assembled in the sleeve hole of eccentric sleeve, requires hard alloy cutter head to be parallel to the position scribe line 312,322 that eccentric sleeve end face is established, and blade is on the short position scribe line direction. The engraved line at this position is usually 0.2mm wide and 0.1mm deep, and is painted red. After correction, use the hexagon socket flat head screw to lock the handle in the sleeve hole. Then connect the eccentric sleeve to the CNC spindle, extend it into the inner hole of the workpiece to be processed and adjust the position, start the spindle, move the tool and lift the tool in the direction of the hole depth, and use the eccentric e to chamfer to the required specification. Finally, by adjusting the position of the tool, the tool can be withdrawn without damaging the surface of the inner hole, and a reverse chamfering process can be completed.

The utility model adopts the cutter bar with olive-shaped cross section, utilizes the cemented carbide cutter with eccentric sleeve structure, and through the control of NC program, it can easily and correctly reverse the chamfering in the machining center (boring machine and vertical milling machine), even if the working range is narrow or The inner hole is deep and can work. It is suitable for reverse chamfering in the range of ￠12-￠42 inner hole. If the eccentric distance e of the eccentric sleeve and the related size of the cutting head are changed, the reverse chamfering of other hole diameters can also be processed.

The utility model can also have other embodiments. All technical solutions formed by equivalent replacement or equivalent transformation fall within the scope of protection required by the utility model.

Claims (5)

1. be used at the bottom of the machining hole the instead cutter at angle, it is characterized in that, described cutter comprises handle of a knife, knife bar, the cutting head that one links to each other, and the eccentric bushing that is socketed on the handle of a knife outside, the carbide chip that links to each other with the cutting head one, there is the eccentric e of tool adjustability in described handle of a knife, knife bar and cutting head zero eccentric synchronous the rotation between described cutting head and the eccentric bushing, satisfy , wherein D is the diameter of angle endoporus instead, and d is the diameter at cutting headband alloy blade blade place, and h is that the height, α at instead angle is the angle at angle instead.

2. according to claim 1 for the cutter at angle instead at the bottom of the machining hole, it is characterized in that: described eccentric bushing comprises that extent of the error is between the M of 1.5～5mm type eccentric bushing and the extent of the error N-type eccentric bushing between 5～17mm.

3. according to claim 1 for the cutter at angle instead at the bottom of the machining hole, it is characterized in that: described knife bar is that section is the olivary hardened steel body of rod.

4. according to claim 1 for the cutter at angle instead at the bottom of the machining hole, it is characterized in that: described eccentric bushing is provided with the trepanning of the eccentric e of tool, and described handle of a knife and trepanning are slippery, and handle of a knife is fastened in the trepanning by the flat head screw that penetrates eccentric bushing.

5. according to claim 1 for the cutter at angle instead at the bottom of the machining hole, it is characterized in that: described eccentric bushing is provided with the position groove towards the one side of cutting head.

Images