CN102476200B - Processing method and processing tool for step deep hole on combined machine tool - Google Patents

Abstract

The invention discloses a method for processing a stepped deep hole on a combined machine tool, which is used for processing a stepped deep hole whose length of the large hole is greater than that of the small hole. And drill the large hole to the depth required by the process; the length of the smaller diameter part of the first step drill is 15 to 25mm, so that a small hole with a corresponding length is formed inside the large hole; use the second step drill to process the large hole Orientation and positioning, and drill small holes to the depth required by the process based on the small hole lead hole; the larger diameter part of the second step drill is a non-cutting section, its diameter is smaller than the diameter of the large hole that has been processed, and the small hole drill When the depth required by the process is reached, the larger diameter part of the second step drill has not yet reached the step end face of the step deep hole. The invention also discloses a corresponding processing tool. The above-mentioned processing method and cutting tool can effectively solve the problems such as easy drilling of stepped small holes and easy breakage of small drill bits in the processing of stepped deep holes.

Description

The Machining Method and the Machining Tool of Stepped Deep Hole on Combined Machine Tool

technical field

The invention relates to a processing method and a processing tool for a stepped deep hole, in particular to a processing method and a processing tool for a stepped deep hole whose length of a large hole is greater than that of a small hole on a combined machine tool.

Background technique

At present, there are two main processing techniques for the stepped deep hole with the length of the large hole greater than the length of the small hole on the combined machine tool: one is that the step 1 (or step 1) first drills the large hole with the stepped deep hole, that is, the large drill bit uses the template The guide sleeve on the upper plate is positioned to drill large holes to the depth required by the process, and then the process 2 (or step 2) is used to drill small holes, that is, the small drill bit is positioned to drill small holes to the depth required by the process with the guide sleeve on the template. The advantages of this process It is to reduce the drilling depth of small drill bits, so as to reduce the problem of small drill bits breaking due to poor rigidity. At present, this process is more commonly used, but its disadvantages are also obvious, because when drilling small holes, the guide sleeve is far away from the small hole, and the guide sleeve is basically Without the positioning function, the small drill bit will drill along the 118° conical surface left by the two cutting edges when the big drill bit drills a large hole, so it is very easy to drill off. The phenomenon of wall penetration; another process is that process 1 (or process step 1) first drills the small hole of the stepped deep hole, that is, the small drill bit is positioned with the guide sleeve on the template to drill the small hole to the depth required by the process, and then process 2 (or Step 2) Drill large holes, that is, the large drill bit is positioned with the guide sleeve on the template to expand the hole to the depth required by the process. The guide sleeves all play a positioning role, so the verticality of the small hole and the coaxiality with the large hole are better, which reduces the occurrence of drilling deviation. easy to break.

Contents of the invention

The purpose of the present invention is to overcome the above-mentioned defects in the prior art. Under the condition that the length of the large hole of the stepped deep hole is greater than the length of the small hole, a processing method and a processing tool are provided, which can effectively solve the problem of small steps in the processing of the stepped deep hole. The hole is easy to drill off, and the small drill bit is easy to break.

The invention provides a method for processing a stepped deep hole on a combined machine tool. The method is used for processing a stepped deep hole whose length of the large hole is greater than that of the small hole. Locate and drill the large hole to the depth required by the process; the larger diameter part of the first step drill is adapted to the diameter of the large hole, and the smaller diameter part of the first step drill is adapted to the diameter of the small hole; and the second The length of the smaller diameter part of the step drill is 15 to 25mm, so that a small hole with a corresponding length is formed inside the large hole. This length design can improve the positioning accuracy of the guide sleeve and effectively avoid drilling deviation and breakage; use The second step drill takes the processed large hole as the guide and locates, and drills the small hole to the depth required by the process based on the small hole lead hole; the larger diameter part of the second step drill is a non-cutting section, and its diameter is smaller than the processed one. When the diameter of the large hole and the small hole are drilled to the depth required by the process, the larger diameter part of the second step drill has not yet reached the step end face of the step deep hole.

Wherein, the diameter of the larger diameter part of the second step drill is 0.05 to 0.10 mm smaller than the diameter of the processed large hole, which enhances the rigidity of the drill while playing the role of guiding and positioning.

Wherein, when the small hole of the stepped deep hole starts drilling, the larger diameter portion of the second stepped drill has a length greater than 15 mm and is located in the large hole of the stepped deep hole for guiding and positioning. It can effectively guarantee the position of the small hole of the stepped deep hole and its coaxiality with the large hole of the stepped deep hole.

Wherein, the drilling mode of the first step drill and the second step drill is an intermittent feed mode. Can effectively improve chip removal and cooling lubrication.

The present invention also provides a tool for machining stepped deep holes on a combined machine tool, which is used for the processing of stepped deep holes whose length of the large hole is greater than that of the small hole, including drilling the large hole to the depth required by the process and forming the leading hole of the small hole. The first step drill and the second step drill for drilling small holes to the depth required by the process; the first step drill is positioned through the guide sleeve on the template, and the second step drill is guided and positioned through the large hole processed by the first step drill; The length of the smaller diameter part of the first step drill is 15 to 20mm, which is used for the processing of small hole lead holes.

Among them, the front end of the two guide ligaments of the second step drill is chamfered and the rear end is not provided with a back angle, so that the larger diameter part of the second step drill can smoothly enter the large hole without damaging the processed large hole. secondary cutting.

Among them, the width of the two guiding ligaments is 2 to 2.5 mm.

Wherein, the larger-diameter part and the smaller-diameter part of the second step drill are connected by a circular arc transition, which can effectively avoid fracture caused by stress concentration.

Among them, the helical surfaces of the first step drill and the second step drill are parabolic surfaces, which can effectively enhance the strength of the drill core and facilitate chip removal.

Compared with the prior art, the present invention has the following beneficial effects:

The technology and processing tool for processing the stepped deep hole with the length of the large hole greater than the length of the small hole on the combined machine tool of the present invention effectively solve the problems that the small hole of the stepped deep hole is easy to drill off and the small drill bit is easy to break, and the product quality is improved. Processing quality reduces production costs.

Description of drawings

Fig. 1 is the drilling schematic diagram of the first step drill in the processing technology of the step deep hole of the present invention on the combined machine tool;

Fig. 2 is the drilling schematic diagram of the second step drill in the processing technology of the step deep hole of the present invention on the combined machine tool;

Fig. 3 is the partially enlarged schematic view of the second step drill of the present invention;

Fig. 4 is a sectional view taken along line A-A of Fig. 3 .

In conjunction with the accompanying drawings, the following reference numerals are marked thereon:

1-workpiece to be processed, 2-guide sleeve, 3-template, 4-first step drill, 5-connector, 6-spindle, 7-spindle box, 8-second step drill, 9-connecting arc, 10 -guide ligament chamfer, 11-guide ligament.

Detailed ways

A specific embodiment of the present invention will be described in detail below in conjunction with the accompanying drawings, but it should be understood that the protection scope of the present invention is not limited by the specific embodiment.

As shown in Figures 1 and 2, the processing method of the step deep hole of the present invention on the combined machine tool adopts compound drilling and cutting, that is, the first step drill 4 is used to drill the large hole of the step deep hole to be processed, and at the same time, the front end of the large hole Form small hole pilot holes; then use the second step drill 8 to drill small holes. The first and second stepped drills are fixedly connected to the main shaft 6 in the headstock 7 through the connecting rod 5 respectively. The larger diameter part of the first step drill 4 is adapted to the diameter of the large hole in the stepped deep hole to be processed, and is used for cutting large holes. The length of diameter part is 15 to 25mm, is used for the pilot hole of cutting small hole; The tool is guided and positioned, and the diameter of the smaller diameter portion of the second step drill 8 is adapted to the diameter of the small hole, and its length needs to be greater than the depth required by the technology of the small hole, so that when the small hole is cut to the depth required by the technology, the second step The end of the larger diameter portion of the drill 8 does not come into contact with the stepped end face, thereby destroying the stepped face already drilled by the first stepped drill 4 . Since the larger diameter part of the second stepped drill 8 is only used for guiding and positioning, not for cutting, its diameter is 0.05 to 0.10mm smaller than the diameter of the large hole of the stepped deep hole. The two leading ligament front ends of the second stepped drill 8 Grind out the chamfer, and the rear end does not grind the rear angle, and the width of the two guide ligaments 11 can be designed to be 2 to 2.5mm, as shown in Figure 3 and Figure 4 (showing the connecting arc 9 and the guide ligament 10).

Processing method of the present invention specifically comprises the steps:

Step 1, use the first step drill 4 to position the guide sleeve 2 on the template 3 to drill the large hole of the stepped deep hole until the depth required by the process is drilled, and at the same time form the lead hole of the small hole at the front end of the large hole.

The small hole guide hole of the stepped deep hole is about 15mm to 25mm deep. The smaller diameter part of the first step drill 4 must be lengthened, and the first step drill is positioned with the guide sleeve on the template when drilling, so if the smaller diameter part is too long, it will cause the first step drill to drill when drilling. 4. The distance from the positioning part of the guide sleeve 2 to the drilling surface of the workpiece increases, thereby reducing the positioning accuracy of the guide sleeve and prone to drilling deviation. In addition, because the rigidity of the smaller diameter part of the step drill is poor, it is easy to break after lengthening.

Step 2, take the large hole of the stepped deep hole (processed in step 1) as the guide and position, and use the second stepped drill 8 to drill the small hole of the stepped deep hole to the process Depth is required.

At this time, the larger diameter part of the second step drill is not cut. As mentioned above, its diameter is 0.05mm to 0.10mm smaller than the diameter of the large hole of the step deep hole. Its function is to guide the positioning and enhance the rigidity of the drill bit. , in order to enable it to be smoothly introduced into the large hole of the stepped deep hole, the front of the two guiding ligaments must be chamfered, and the rear corner is not allowed to be ground. The width of the two guiding ligaments is designed to be 2mm to 2.5mm; at the same time, the second The larger diameter part of the step drill 8 is connected with the smaller diameter part of the second step drill 8 with a circular arc transition, which can effectively reduce the stress at this place and prevent the smaller diameter part of the second step drill 8 from breaking off; in order to ensure The position of the small hole of the stepped deep hole and its coaxiality with the large hole of the stepped deep hole must ensure that when the small hole of the stepped deep hole starts drilling, the larger diameter part of the second stepped drill has a step depth greater than 15mm The guide positioning in the large hole of the hole; and when the small hole of the stepped deep hole is drilled to the depth required by the process, the larger diameter part (ie the guide part) of the second stepped drill 8 cannot be in contact with the stepped end face of the small hole of the stepped deep hole (As mentioned earlier, as long as the length of the smaller diameter portion of the second step drill is guaranteed to be greater than the small hole length), this must be noticed when designing the step drill.

In order to enhance the strength of the drill core and facilitate chip removal, the helical surfaces of the first stepped drill 4 and the second stepped drill 8 used in the above steps 1 and 2 are designed and manufactured as parabolic surfaces; in order to improve chip removal and cooling lubrication, step 1 And step 2 can adopt the mode of intermittent feeding during processing.

In summary, the process of machining a stepped deep hole in which the length of the large hole in the workpiece 1 is greater than the length of the small hole on the combined machine tool is as follows: use the first stepped drill 4 to position the guide sleeve 2 on the template 3, and drill the hole in the workpiece 1. The large hole of the stepped deep hole and the lead hole of the small hole, after multiple intermittent feeds, the large hole of the stepped deep hole of workpiece 1 is drilled to the depth required by the process, and the small hole of the stepped deep hole in workpiece 1 is drilled to the depth required by the process. The depth is 15mm~20mm; use the second step drill 8 to drill the workpiece after multiple intermittent feeds based on the large hole of the stepped deep hole in the processed workpiece 1 as the guide for positioning and the small hole of the stepped deep hole as the basis The small hole of the stepped deep hole in 1 reaches the depth required by the process, and the processing of the entire stepped deep hole is completed so far.

The technology and processing tool for processing the stepped deep hole with the length of the large hole greater than the length of the small hole on the combined machine tool of the present invention effectively solve the problems that the small hole of the stepped deep hole is easy to drill off and the small drill bit is easy to break, and the product quality is improved. Processing quality reduces production costs.

The above disclosure is only a specific embodiment of the present invention, however, the present invention is not limited thereto, and any changes conceivable by those skilled in the art shall fall within the protection scope of the present invention.

Claims (8)

1. A processing method for stepped deep holes on a combined machine tool, used for the processing of large hole lengths greater than the stepped deep holes of small hole length, is characterized in that, comprises the steps: Use the first step drill to position with the guide sleeve on the template, and drill the large hole to the depth required by the process; the larger diameter part of the first step drill is adapted to the diameter of the large hole, and the smaller diameter of the first step drill The part is adapted to the diameter of the small hole; and the length of the smaller diameter part of the first step drill is 15 to 25 mm, so that a small hole with a corresponding length and size is formed inside the large hole; Use the second step drill to guide and locate the large hole processed, and drill the small hole to the depth required by the process based on the small hole guide hole; the larger diameter part of the second step drill is a non-cutting section , whose diameter is smaller than the diameter of the processed large hole, and when the small hole is drilled to the depth required by the process, the larger diameter part of the second step drill has not yet reached the step end face of the step deep hole; The drilling mode of the first step drill and the second step drill is an intermittent feed mode. 2. The method for processing stepped deep holes on a combined machine tool according to claim 1, wherein the diameter of the larger diameter portion of the second stepped drill is 0.05 to 0.10 smaller than the diameter of the processed large hole. mm. 3. according to the processing method of step deep hole described in claim 1 or 2 on combined machine tool, it is characterized in that, when the small hole of described step deep hole starts drilling, the larger diameter part of the second step drill has more than The 15mm length is located in the large hole of the stepped deep hole for guiding positioning. 4. A tool for processing stepped deep holes on a combined machine tool, used for the processing of stepped deep holes whose length of the large hole is greater than that of the small hole, it is characterized in that it includes drilling the large hole to the depth required by the process and forming a small hole leading hole The first stepped drill and the second stepped drill used to drill small holes to the depth required by the process; the first stepped drill is positioned through the guide sleeve on the template, and the second stepped drill is processed by the first stepped drill Large hole guiding and positioning; the length of the smaller diameter part of the first step drill is 15 to 20mm, which is used for the processing of small hole leading holes. 5 . The tool for machining stepped deep holes on a combined machine tool according to claim 4 , wherein the front ends of the two guide ligaments of the second stepped drill are chamfered and the rear ends are not provided with rear corners. 5 . 6 . The tool for machining stepped deep holes on a combined machine tool according to claim 5 , wherein the width of the two guiding ligaments is 2 to 2.5 mm. 7 . The tool for machining stepped deep holes on a combined machine tool according to claim 4 , wherein a circular arc transition connection is formed between the larger diameter portion and the smaller diameter portion of the second stepped drill. 8 . 8. The tool for machining stepped deep holes on a combined machine tool according to claim 4, wherein the spiral surfaces of the first stepped drill and the second stepped drill are parabolic surfaces.

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