RU2229376C2 - Planing tool with angle of action and profile of chip breaker on its front face renovated at regrinding - Google Patents

Abstract

FIELD: wood-working industry, in particular, tools for wood working. SUBSTANCE: the planing tool has a shaft with trapeziform grooves, in which cutters are fixed by means of wedges and stay bolts, the front surface of the cutters is made with a curvilinear recess for the chip breaker. The cutter on the front surface has a ridge, and the wedge on the surface facing the cutter has a shoulder for engagement with the ridge preventing fly-out of the cutter at a slackening of wedge fixation by bolts. EFFECT: enhanced service life of cutter, their durability, as well as reliability of fixation of cutters and wedges. 8 dwg

Description

1. The invention relates to the field of machine tool industry, in particular to machines for treating wood with cutters mounted on rotating knife shafts.

2. Analogs - shafts and chisel (milling) heads of woodworking jointing (sizing), planers and milling machines.

3. The prototype - widespread d / o machines with wedge-mounted knives in the grooves of rotating knife shafts.

Positive properties of the prototype

1. Ease of manufacturing cutting knives from any scrap metal strip of suitable stiffness.

2. The relative reliability of the mounting of the knives in relation to the danger of their ejection during operation.

3. The relative simplicity of manufacturing a knife shaft with grooves (in terms of accuracy).

Negative properties of the prototype

1. The temptation for the operators to develop knives during regrinding to an excessively small residual width, fraught with unreliable fastening and the danger of ejection during operation.

2. The absence of structural elements that prevent the excessive development of knives during regrinding, as well as the wedge.

The purpose of the invention

1. Increasing the operational life of the cutters by increasing their active mass without increasing the dimensions of the knife shaft and the maximum possible number of regrinds, besides without removing from the knife shaft, and the associated need for subsequent operations to bring the cutting edges of all cutters to a single cutting radius. Re-sharpen the cutters with removal from the knife shaft to carry out no more than once every two or more months.

2. To increase the longevity of the incisors to their full development - at least six months.

3. Higher reliability of fastening of cutters and wedges, excluding their ejection during operation.

Ways to solve the problem

1. Performing regrinding (metal removal) along the front (in the direction of rotation) face of the cutters with a complete update of the active part of the cutting profile, including the filler angle and chip breaker profile, without removing the cutters from the knife shaft and the associated violation of the adjustment of all cutters to a single cutting radius .

2. Performing control backing of the incisors associated with removing them from the knife shaft only when moving to the next layer of regrinding.

List of Signs of Significant Novelty

1. Performing the regrinding of the cutters along their frontal face with a complete update of the profile of their active cutting part, including the filler angle (rake angle) and the chip breaker profile without removing the cutters from the knife shaft and violating the setting of their cutting edges to a single cutting radius. The removal of cutters from the shaft is carried out only when moving to the next row of regrind cutters (not more than once every 2 months).

2. Constructive limitation of the degree of extension of the cutters in width (height), taking into account their development in the form of a ridge on the cutter and a ledge on the wedge, eliminating the danger of their ejection during operation of the machine.

3. The geometric configuration of the cutter and the wedge, combined installed in the working groove of the shaft, eliminates their ejection on the move of the machine even in the complete absence of wedge spacer bolts.

Figure 1 shows the pairing of a cutter of increased thickness, having a comb with a wedge having a ledge, on which the comb rests, which together limit the extension of the cutter, as well as a screw that controls the degree of extension during adjustment.

Figure 2 shows a traditionally used knife with a scheme of regrinding at the back (back) angle.

Figure 3 shows a diagram of the proposed cutter of increased mass with layer-by-layer regrinding performed along the front face with the formation of the additive angle (front angle) and the chip breaker profile.

Figure 4 shows a wedge in plan with recesses in which spacer bolts are placed.

Figure 5 shows the cutter shaft in section with the fastening of a new, not subjected to sharpening a traditional full-width knife.

Figure 6 shows a knife shaft in the context with the fastening of a re-sharpened knife dangerous to use, a possible tear (release) is shown by an arrow.

Figure 7 shows the cutter of the proposed design in the position of the limit of possible use.

On Fig shows the active cutting part of the cutter, including the filler angle (rake angle), the chamfer formed when all the cutters are brought out to a single cutting radius, and the chip breaker contour.

Specification Explanatory

1. Val

2. Wedge

3. Wedge spacer bolt

4. Cutter (knife)

5. Comb

6. The ledge

7. Profile of the cutting part of the cutter

8. Set screw

9. Threaded hole for screw (8)

10. Profile abrasive wheel

11. The knife is traditional new

12. Traditional crafted knife

13. The sharpened (back) surface of a traditional knife

14. The developed cutter of the proposed design

15. Shaft groove

16. The recess in the wedge 2 for the spacer bolt

17. Backing of a back corner of a cutter

18. Old design wedge chip breaker

19. The angle of the additive cutter (rake angle)

20. Backing angle (when backing up the shaft itself)

21. Chip breaker circuit

22. Recess in the body of the wedge to accommodate the spacer bolt

Installation and fastening of a cutter a wedge (static)

In each groove 15 of the knife shaft 1 there is a cutter 4 with a trapezoidal wedge 2 (FIGS. 1, 4 and 7), in the recesses 16 of which spacer bolts 3 are placed. The dimensions of the groove 15 are such that the cutter 4 and the wedge 2 can be inserted together and can only be removed from the shaft end, which eliminates their spontaneous loss from the groove even in the absence of spacer bolts. Each cutter 4 is set to the desired degree of extension by two set screws 8, which are available in each groove 15 and placed on the end sections of the cylinder of the shaft 1.

Commissioning and operational work on the cutting unit of the knife shaft (dynamics)

The blanks of the cutters 4, having the shape of bars of a quadrangular section (FIGS. 1 and 7), the backed face 17 and the comb (FIG. 1, pos. 5), are inserted together with the wedges 2 having a ledge 6 into the grooves 15 of the shaft 1 and are exposed by screws 8 to the required position (according to the degree of advancement). Spacer bolts 3 using wedges 2 the position of the cutters 4 is fixed. The shaft 1 is driven in rotation. By means of a sharpening device, an abrasive block is brought to the rotating shaft, which grinds the protruding sections of the cutters in the area of future edges and creates narrow chamfers along their entire length (Figs. 7 and 8), indicating that the cutting edges of all cutters are on a uniform cutting radius. After that, the profiled part of the abrasive wheel 10 (corundum, diamond) selects and forms the profile and the angle of addition of the cutter (Fig.8 pos.19) of the cutter 4 relative to the plane of the processed wooden blanks, as well as a curved section of the chipbreaker (Fig.8 pos.21). In practice, yesterday and today, for the machine tool industry, chip breaker 18 is placed on the wedge, wears out and generally triples when making home-made wedges instead of factory-made wedges. The chip breaker 21 of the proposed cutter is updated at each sharpening, on average once a shift, i.e. 2-3 times a day.

The maximum degree of bluntness of the cutting edge of the cutter is taken equal to R = 0.1 mm, i.e. with each regrinding a metal layer is removed up to 0.12 mm. When the chamfer (Fig. 8), which indicates the operation of all the cutters on the same cutting radius, disappears during the next regrinding, either the extension of the cutters 4 with the adjusting screws 8 is performed, or the radius is reduced by a fraction of mm, on which the uniform radius of the cutting edges of all the cutters is located. The first option is preferable, because with subsequent regrinding, a decrease in the cutting radius of the cutters again occurs and a change in the position of the front table of the machine in height will be required.

When moving to the next sharpening layer, the cutters are removed from the shaft. Their control backing is carried out, then with the help of screws 8 they are set to a new sharpening level in the grooves 15 of the knife shaft 1 and fixed with wedges 2. Then all the above operations and transitions are repeated.

Claims (1)

A planing tool containing a shaft with trapezoidal grooves in which the cutters are fixed by means of wedges and expansion bolts, characterized in that the front surface of the cutters is made with a curved recess for the chip breaker, the cutter on the front surface has a comb, and the wedge has a ledge on the surface facing the cutter for interaction with the crest, excluding the emergence of the incisor when the wedge is loosened by bolts.

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