CN104588785A - Inner-cooling type hobbing cutter - Google Patents

Abstract

The invention provides an internally cooled hob, which includes a cutter bar and a hob; the hob is located in a chip groove corresponding to the rake face of the cutter tooth and is provided with an oil hole; the upper part of the oil hole is correspondingly provided with a hole plug, The lower part is connected to the relief groove of the hob; the hole plug with the spray hole on the head is connected with the oil hole through the thread; the cutter rod is provided with the axial oil hole of the cutter rod, and the The radial oil hole of the cutter rod; the axial oil hole of the cutter rod communicates with the central hole of the joint stator through the central hole of the joint rotor. The present invention adopts the oil hole in the hob and the hole plug to realize the opening and closing of the hole, so that the cutting oil/liquid and compressed air are directly sprayed to the rake face of the hob tooth through the oil hole, and the cooling and lubricating effect is fully utilized. The function is to reduce the temperature of the hob and prolong the life of the hob. The hob can directly spray the cooling medium to the vicinity of the cutting area, take away the cutting heat to the greatest extent, and reduce the influence of the cutting heat on the hobbing process.

Description

An internally cooled hob

technical field

The invention belongs to the field of metal cutting tools, and relates to a gear hob, in particular to an internal cooling hob suitable for gear hobbing.

technical background

As a mechanical component that transmits motion and power, gears are key basic transmission components in industries such as automobiles, ships, aerospace, metallurgy, and wind power. The gear hobbing process is one of the most widely used gear processing processes at present. It has the characteristics of high production efficiency and belongs to a large-volume and wide-ranging mechanical processing process. The gear hobbing process is different from cutting processes such as turning. During the intermittent cutting process of the hob, its teeth are subjected to thermal shock loads due to severe extrusion and friction with chips and workpieces. This thermal shock load aggravates the hob The wear and tear shortens the service life of the hob. As one of the basic tools for gear hobbing, the hob is highly valued by the industry for its service life, design and manufacturing costs.

In order to prolong the service life of the hob and reduce the cost, pouring wet cutting hobbing or dry hobbing is usually used. For cast-type wet cutting gear hobbing, although the use of a large amount of cutting oil/fluid is beneficial to the cooling and lubrication of the hob, it has the following disadvantages: (1) The contact area between the knife and chips is in a boundary friction state, and the large particle cutting It is difficult for oil/liquid to form fluid lubrication, but it works by penetrating into the gap of the knife-chip contact area, and the cooling and lubrication effect is severely limited. (2) During the reverse hobbing process, the heavy cutter teeth isolate the cutting oil/fluid from the rake face of the cutter tooth, making it difficult for the cutting oil/fluid to reach the cutting area; The cutter face is surrounded by chips, and it is difficult for cutting oil/fluid to reach the cutting area smoothly. (3) The extensive use of cutting oil/fluid not only increases the processing cost, but also is the main source of environmental pollution and occupational health hazards for workers.

As far as dry hobbing is concerned, developed countries in Europe and the United States have achieved good development and successfully applied it in industrial production. The country started relatively late in this area, and key technologies such as machine tool technology and cutting tool technology still need to be overcome urgently. Although dry hobbing has the characteristics of green and environmental protection, there are still the following problems: (1) Due to the elimination of the use of cutting oil/fluid and the use of dry hobbing, the friction between the knife-chip and knife-workpiece is extremely severe, which increases the The requirements of tool structure, base material and coating process are specified. (2) Improving the base material of the hob and the use of coating materials with good heat resistance significantly increase the manufacturing cost of the hob and pose new challenges to the coating technology of the hob. (3) The high temperature in the dry hobbing process is likely to cause deformation of the workpiece and affect the machining accuracy of the gear.

purpose of invention

In view of the above-mentioned deficiencies in the prior art, the purpose of the present invention is to provide an internal cooling hob to solve the problems of poor spraying of cutting oil/liquid and compressed air and increase processing costs of cast-type wet cutting hobbing; and dry hobbing Toothed hobs have severe friction, wear resistance is affected, and the service life of the hob is affected.

To achieve the above purpose, the present invention adopts the following technical solutions: an internally cooled hob, including a cutter bar and a hob; it is characterized in that the hob is sleeved on the cutter bar; the hob is fixed by a key to freely rotate in its axial direction Degree of freedom, the degree of freedom of axial movement is fixed by the gasket, and the other four degrees of freedom are restricted by the cutter rod, so as to be fixed on the cutter rod; the hob head seat is connected with the rotary joint through threads;

The hob is located in the chip pocket corresponding to the rake face of the cutter tooth and is provided with an oil hole; the upper part of the oil hole is correspondingly provided with a hole plug, and the lower part is connected to the relief groove of the hob; the hole plug is connected with the oil through the thread. The hole is connected, and the head of the hole plug is equipped with an oil injection hole;

The cutter rod is provided with a cutter rod axial oil hole, and a cutter rod radial oil hole connected with the cutter rod axial oil hole; the cutter rod axial oil hole communicates with the center hole of the joint stator through the center hole of the joint rotor; The radial oil hole of the rod communicates with the oil hole through the undercut groove.

Further, the main body of the hole plug is cylindrical and the top is hexagonal; the hole plug is provided with a hole plug oil hole in the axial direction, a hole plug boss oil hole in the radial direction, and an external thread near the bottom end.

Further, the hole plug bottom cover is connected with the hole plug through interference fit.

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

1. The hole plug is used to realize the injection of cutting oil/fluid and compressed air or not according to the machining status of the cutter teeth, which can avoid unnecessary waste caused by the four injections of cutting oil/fluid and compressed air, thereby reducing cutting oil/fluid and compressed air The dosage, reduce the processing cost.

2. Adopt the oil hole in the hob and the hole plug to realize the opening and closing of the hole, so that the cutting oil/liquid and compressed air can be directly sprayed to the rake face of the hob tooth through the oil hole, and the cooling and lubrication can be fully utilized The function is to reduce the temperature of the hob and prolong the life of the hob. The hob can directly spray the cooling medium to the vicinity of the cutting area, take away the cutting heat to the maximum extent, and reduce the influence of the cutting heat on the hobbing process.

Moreover, the cutting oil/fluid is directly sprayed onto the rake face of the hob tooth through the hole, which is beneficial to reduce the friction between the hob and the chips, improve the wear resistance of the hob, and prolong the life of the hob.

3. An oil channel is set up in the chip pocket corresponding to the rake face of the cutter tooth, which is conducive to the separation of chips from the surface of the hob, refines the surface roughness of the workpiece, reduces wear of the hob, and prolongs the life of the hob. When the cutting oil/fluid and compressed air flow through the hob, they circulate inside the hob and cool the base of the hob, which is beneficial to reduce the temperature of the hob, reduce the processing error caused by thermal deformation and prolong the life of the hob.

Description of drawings

Figure 1 is a schematic structural view of the internal cooling hob of the present invention: (a) perspective view; (b) partial sectional view.

Fig. 2 is a half sectional view of Fig. 1 .

Fig. 3 is a radial sectional view of the internal cooling hob of the present invention: (a) radial sectional view; (b) partial enlarged view.

Fig. 4 is a hole plug and a hole plug bottom cover: (a) head; (b) bottom; (c) half sectional view.

In the figure, 1 is the rotary joint, 2 is the head seat of the hob, 3 is the washer, 4 is the hob, 5 is the washer, 6 is the knife rod, 7 is the oil hole, 8 is the radial oil hole of the knife rod, and 9 is the Hole plug, 10 is the bottom cover of the hole plug, 11 is the tool relief groove, 12 is the axial oil hole of the cutter bar, 13 is the key, 1-1 is the joint stator, 1-2 is the joint rotor, 7-1 is the oil channel On the step surface, 9-1 is the injection hole of the hole plug, 9-2 is the outer hexagon of the hole plug, 9-3 is the oil hole of the hole plug, and 9-4 is the oil hole of the hole plug boss.

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings and specific embodiments.

As shown in Figure 1, an internally cooled hob includes a cutter bar 6 and a hob 4, and the hob 4 is sleeved on the cutter bar 6; the hob 4 is connected by a key 13 to fix its axial rotation degree of freedom. The washers 3 and 5 fix the degree of freedom of axial movement, and the other four degrees of freedom are restricted by the cutter rod 6, so as to be fixed on the cutter rod 6; the hob head seat 2 plays the role of supporting the cutter rod 6, and also through the thread Connect with rotary joint 1.

Referring to Fig. 1 and Fig. 2, on the basis of the existing hob structure, the hob 4 is provided with an oil channel 7 in the chip pocket corresponding to the rake face of the cutter tooth; the upper part of the oil channel 7 is correspondingly provided with The hole plug 9 communicates with the undercut groove 11 of the hob 4 at the bottom.

The cutter bar 6 is provided with the cutter bar axial oil hole 12, and the cutter bar radial oil hole 8 communicated with the cutter bar axial oil hole 12; the cutter bar axial oil hole 12 passes through the center hole of the joint rotor 1-2 and The central hole of the joint stator 1-1 is connected; the radial oil hole 8 of the tool rod is connected with the oil hole 7 through the tool relief groove 11 .

Referring to FIG. 3 , the hole plug 9 is connected with the oil hole 7 through threads.

Referring to Fig. 4, the main body of the hole plug 9 is a cylindrical body, and the top is a hole plug hexagonal head 9-2, on which a hole plug injection hole 9-1 is arranged; the hole plug 9 is axially provided with a hole plug oil hole 9- 3. There is a hole plug boss oil hole 9-4 in the radial direction; the end of the hole plug 9 near the bottom is also provided with an external thread;

The hole plug bottom cover 10 is connected with the hole plug 9 through an interference fit.

Further, the aperture size of the oil channel 7 is set according to the size of the hob; the opening and closing of the oil channel 7 is realized by manual adjustment of the hole plug 9 according to the processing state of the circumference of the cutter teeth.

The specific working mode of the internal cooling hob in the present invention is as follows: the cutter bar 6 is fixed on the hob frame of the hobbing machine tool, and the hob 4 is installed on the cutter bar 6 . Cutting oil/fluid and compressed air enter the center hole of the joint rotor 1-2 through the inlet of the joint stator 1-1. Since the center hole of the joint rotor 1-2 communicates with the axial oil hole 12 of the cutter bar, the cutting oil/liquid and Compressed air can smoothly pass through the axial oil hole 12 of the cutter bar and enter the radial oil hole 8 of the cutter bar, and enter the oil channel 7 after passing through the tool relief groove 11; further, the cutting oil/liquid and compressed air enter the hole plug 9 and flow from The hole plug injection hole 9-1 is injected to the rake face of the hob cutter tooth.

The hole plug 9 is used to open and close the oil channel 7: before the hob is shifted, it is judged whether the circle where the cutter tooth is located is a cutting circle or a non-cutting circle. For the cutting circle, a wrench is used to rotate the outer hexagon 9-2 of the hole plug to make the bottom of the hole plug The cover 10 is far away from the oil hole step surface 7-1, so that the oil hole 7 communicates with the hole plug oil hole 9-3 through the hole plug boss oil hole 9-4, thereby realizing the smooth spraying of cutting oil/liquid and compressed air. out. For the non-cutting machining circle, use a wrench to rotate the hole plug outer hexagon 9-2 so that the hole plug bottom cover 10 is close to the oil channel step surface 7-1, because the diameter of the hole plug bottom cover 10 is greater than the diameter of the oil channel 7 lower end channels, thus Make the oil hole 7 and the hole plug oil hole 9-3 disconnected, thereby preventing the ejection of cutting oil/liquid and compressed air.

In the present invention, an oil hole is provided in the chip groove corresponding to the rake face of each tooth of the hob, so that the cutting oil/liquid and compressed air flow through the oil hole and are directly sprayed onto the rake face of the hob. In order to avoid cutting oil/hydraulic pressure insufficient to reach the rake face of each cutter tooth evenly due to simultaneous injection of multiple oil holes and reduce unnecessary waste caused by cutting oil/liquid spraying everywhere, it is realized by adjusting the hole plug The opening and closing of the oil hole.

Finally, it is noted that the above embodiments are only used to illustrate the technical solutions of the present invention without limitation. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be carried out Modifications or equivalent replacements without departing from the spirit and scope of the technical solution of the present invention shall be covered by the claims of the present invention.

Claims (5)

1. An internally cooled hob, including a cutter bar (6) and a hob (4); it is characterized in that the hob (4) is sleeved on the cutter bar (6); the hob (4) passes through the key ( 13) Connect to fix its axial rotation degree of freedom, fix its axial movement degree of freedom through washers (3) and (5), and limit its other four degrees of freedom through the knife rod (6), thereby fixing it on the knife rod (6) Upper; the hob head seat (2) is connected with the rotary joint (1) through threads; The hob (4) is located in the chip pocket corresponding to the rake face of the cutter tooth and is provided with an oil hole (7); the upper part of the oil hole (7) is correspondingly provided with a hole plug (9), and the lower part is connected to the hob (4 ) of the tool relief groove (11); the hole plug (9) is connected with the oil channel (7) through threads; the head of the hole plug (9) is provided with a hole plug injection hole (9-1); The cutter rod (6) is provided with the cutter rod axial oil hole (12), and the cutter rod radial oil hole (8) connected with the cutter rod axial oil hole (12); the cutter rod axial oil hole (12) The center hole of the joint rotor (1-2) communicates with the center hole of the joint stator (1-1); the radial oil hole (8) of the tool rod communicates with the oil channel (7) through the relief groove (11). 2. The internally cooled hob according to claim 1, characterized in that the main body of the hole plug (9) is a cylindrical body, and the top is an outer hexagon (9) with a hole plug injection hole (9-1). -2); the hole plug (9) is provided with a hole plug oil hole (9-3) in the axial direction, and a hole plug boss oil hole (9-4) in the radial direction; the hole plug (9) is provided with an outer thread; the bottom of the hole plug (9) is connected with the bottom cover of the hole plug (10) through interference fit. 3. The internally cooled hob according to claim 1, characterized in that, the radial oil holes (8) of the cutter bar are set to 1, 2, 3 or more. 4. The inner cooling hob according to claim 1, characterized in that the central axis of the radial oil hole (8) of the cutter bar can be collinear with the central axis of the oil hole (7), that is, the cutter bar The radial oil holes (8) are helically arranged along the cutter bar (6) according to the helical manner of hob cutter teeth. 5. The inner cooling hob according to claim 1, characterized in that the central axis of the radial oil hole (8) of the cutter bar may not be collinear with the central axis of the oil hole (7), that is, the knife The rod radial oil holes (8) are not arranged helically along the cutter rod (6) according to the helical manner of hob cutter teeth.