RU35745U1 - Broach for processing grooves and ledges - Google Patents

Description

2003127525

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II Hill ns ill, j r r j 4 5MKI B23D 43/02

Broach for grooving and yielding.

The utility model relates to mechanical engineering and can be used for processing grooves and ledges.

Known broaching with a free exit of chips in which the depth of the chip groove along the blade changes, which ensures fast chip removal from the cutting zone when processing shallow grooves, while processing deep grooves, a tendency to stack chips, increasing the cutting force on the walls of the groove, deformation of the walls of the groove, which affects the quality of processing (High-performance drawing / V.F. Skizhenok, V.D. Lemeshonok, V.P. Tsegelnik. - M.: Mechanical Engineering, 1990 - 240 pp., ill. p. 113).

There is also a method of pulling grooves and a broaching unit for its implementation (see RF patent. No. 2151031, Ml. B23D43 / 02, Bull. No. 17, 06/20/2000), in which the first section operates on a generator cutting scheme with free chip flow, in which the main cutting edge is perpendicular to the bottom of the chip groove, and the depth of the chip groove exceeds the width of the cut allowance, the angle of inclination of the main cutter; its edges are 0 °. Feed per tooth in tenths of a millimeter. The length of the auxiliary cutter; its edges correspond to the depth of the cut allowance.

This broach provides the removal of a large amount of chips from the cutting zone since Free chip output is ensured and feed per tooth can be increased. The disadvantages of this design is that if it is necessary to divide the chips of considerable width, chip separation grooves are used that leave stiffeners, which increases the cutting force, especially at high feeds, and the wear of the cutters;

Edges, as well as due to the lack of an inclination angle of the cutting edge, an uneven cutting process occurs, especially with small drawing lengths.

The technical problem to which the utility model is directed is to improve the quality of processing and tool life by reducing the length of the broach and increasing the uniformity of movement during processing.

This problem is solved by the fact that in the specified broach for processing grooves and ledges according to the generator cutting scheme with large feeds per tooth, with an inclination angle of the cutting edge of 0 ° and with grooves for the free exit of the chips, the cutting edge is made in cascade, consisting of at least , from the 1st stage, and the height of the cascade stage and the amount of feed per tooth are related by:

/ 2 iS-sin; r,

h is the height of the stuceni;

S is the amount of feed per tooth;

y is the front angle of the broach blade,

while the cutting edge can be divided into sections with a shift

sequentially one relative to the other by the value of S, and the value

the shear and the amount of feed per tooth are related by:

S S-tgr,

d is the magnitude of the shift;

S is the amount of feed per tooth;

7 - the front angle of the broach blade.

The distinguishing features of the proposed broach from the above, closest to it, is the presence of a cascade cutting edge, consisting of at least one step, with a height of the cascade step of a certain size, which allows you to divide the chip width by

narrower strips without chip separation grooves, as well as the fact that the cutting edge is divided into sections with a shift sequentially relative to each other by a certain amount, which allows to increase the smoothness of the tool, to increase its durability.

The applicant is not aware of broaches for processing grooves and ledges with the specified combination of essential features and the claimed combination of essential features does not follow explicitly from the current level of technology, which confirms the compliance of the claimed technical solution with the condition of "novelty.

The claimed technical solution is illustrated by drawings, where: FIG. 1 - the main view of the proposed broach for processing grooves and ledges; figure 2 is a top view of the proposed broach for processing grooves and ledges; fig.Z is a side view of the proposed broach for processing grooves and ledges; 4 is a diagram of the processing of the part; Fig. 3 - remote element A in figure 2; 6 - remote element B in FIG. 1.

The broach 1 is fixed on the slider plate of the machine (not shown) to the keyway 2 and fixed with screws in the holes 3. The broach contains on both sides of the blade 4 without an angle of inclination of the main cutting edges having a front angle y and perpendicular to the bottom of the grooves 5 for free chip exit . The grooves 5 have a depth B1 greater than the width of the cut allowance B. The total length of the main cutting edges of the cascade B2 exceeds the depth of the chip grooves B1. The length of the BW of the auxiliary cutting edges 6 exceeds the depth of the cut allowance P. The broach 1 has a generator cutting scheme, and the main cutting edge is cascaded, consisting of steps, the cutting edges of which are divided into sections 7, 8, 9 with a shift relative to one another.

Consider the process of pulling the claimed broach. The broach 1 mounted on the slider plate of the machine (not shown) on the keyway 2 and fixed with screws in the holes 3 is moved in the V direction

relative to the stationary part and each blade 4 cuts off the cap with an S value, measured in tenths of a millimeter. Cascade cutting edge, with cascade height h defined by the relationship:

 sin y

h is the height of the step;

S is the amount of feed per tooth;

y is the front angle of the broach blade,

divides shavings of width B into three strips, facilitating chip removal along

grooves 5 for a free exit of chips in the direction of R. Cutting

the edge having a rake angle y is divided into sections 7, 8, 9 with a shift

successively one relative to the other by a value of b, we determine} then

dependency:

5 S-tgY,

d is the magnitude of the shift;

S is the amount of feed per tooth;

y is the front angle of the broach blade.

These edges come into operation one after another, providing smoothness and uniformity of the load, increasing the quality of processing and tool life. The side walls of the groove are formed by auxiliary cutting edges 6.

The broach for processing grooves and ledges can be performed on standard equipment using modern materials and technologies.

Claims (2)

1. A broach for processing grooves and ledges according to a generator cutting scheme with large feeds per tooth, with an inclination angle of the cutting edge equal to 0 °, and with grooves for the free exit of chips, characterized in that the cutting edge is made in cascade, consisting of at least , from the 1st stage, and the height of the cascade stage and the feed rate per tooth are related by

where h is the height of the step; S is the amount of feed per tooth; γ is the rake angle of the broaching blade. 2. The broach according to claim 1, characterized in that the cutting edge is divided into sections with a shift in series relative to each other by a value of δ, while the amount of shift and the amount of feed per tooth are related

where δ is the magnitude of the shift; S is the amount of feed per tooth; γ is the front angle of the broach blade.