RU2480289C2 - Cutter knife and cutting head equipped therewith - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: cutter knife 1 comprises falcate blade 6 with arched cutting edge 7 and inner arched undercut 12 with thickness D decreasing radially outward. Chamfers 8, 9 of cutting edge 7 and undercut 12 are located at first side 11 of blade 6. Decrease in thickness D of blade 6 results from chamber 15 extending at second side 13 of blade 6. Blade 6 has visible regrinding area 109 at arched cutting edge 7. Thickness Dn of blade 6 in regrinding area 109 is smaller than thickness Dm in medium area 108 of blade 6. Regrinding area 109 has almost parallel lateral surfaces 117, 118. Regrinding area 109 may change into blade 6 via transitional area 120 including grooves 119. Cutter head is furnished with, at least, one knife 1.

EFFECT: higher efficiency and fast recovery of cutting edge.

32 cl, 8 dwg

Description

The invention primarily relates to a cutter knife of a certain type and in addition to a knife head containing at least one of such cutting knives.

Cutter knives are used to grind and mix meat, raw sausage or sausage meat, or similar food products, hereinafter referred to simply as mass, in a device, the so-called cutter, and, in particular, they have long been known in the meat processing industry in numerous forms and designs . Typically, several knives are axially mounted on the drive shaft next to each other and / or circumferentially in the same plane, forming the so-called knife head (see the description of the patent of the applicant DE 3732237 C1). There, the main task of the cutter knives is to grind and mix the mass contained in the cutter to a certain desired degree. This processing process should be carried out as quickly as possible, but at the same time with minimal energy consumption and thoroughly, as well as without excessive heating of the mass. When processing the mass, the cutter knives must withstand significant cutting and bending forces. The fact is that a breakdown during operation leads not only to long downtime. Along with replacing the knife, repairing the damage often also requires high costs caused by a broken knife in the cutter itself. Finally, a breakdown due to the risk of splinters also means unsuitability for use of the entire mass contained in the cutter.

The cutter knife and the knife head equipped with it have long been known in numerous designs. Knives, for example, with semicircular flat fastening sections, with an external cutting edge and with an undercut located inside, are known (see, for example, description of patent CH 673236 A5). However, there are also cutter knives with a round mounting portion, with a mounting portion in the form of a portion of a circle, or with another mounting portion. In addition, from practice it is known that the thickness of the blade should decrease in the direction of the tip.

Typically, at a cutter knife, the blade tapering in the direction of the tip is made in such a way that the front bevel is located on one narrow side as the cutting edge itself, while the bevel or undercut is also located on the other opposite rear narrow side, also called the back side. .

In accordance with the aforementioned prior art, for cutter knives, in general, a blade, and thereby a cutting edge, is subject to wear when used. Ultimately, the cutting edge becomes dull so that it can no longer perform its task sufficiently. It needs to be dragged. The wear of the tip of the cutting edge is much greater than in the direction of the axis of rotation of the blade. The spatial shape of the cutting edge, i.e. arc shape and bevel angle, optimized for each application. If this optimized shape needs to be restored again as a result of excessive wear, then the bevel must be re-sharpened not only on or near the point, but along the entire length of the blade. Therefore, such a regrinding requires a substantial removal of the material, and, therefore, is very time-consuming.

In the aforementioned knife heads, consisting, for example, of three to eight knives, separate adjacent knives can perform various tasks: in particular, knives located axially outside can also supply mass to the internal knives. The cutter knives facing the mass entering the cutter serve, so to speak, as serving knives, while the more distant knives serve as so-called retaining knives. How many and what kind of knives of this kind will be mounted together in a knife head depends primarily on the consistency, i.e. hardness and toughness of a particular processed mass, therefore, knives in a knife head even geometrically can be made in different ways.

Based on the diverse requirements for a cutter knife of this kind and discussed above, the invention is based on the desire to create a geometric shape that increases the efficiency of the cutter knife by optimizing the fracture resistance and / or providing a very fast and low-cost restoration of the optimal shape of the cutting edge.

To this end, the invention provides an embodiment in accordance with the characterizing part of claim 1 and / or claim 6.

Thus, the invention consists in a cutter knife mounted by at least one flat fastening portion in the form of a part of a circle rotatably about an axis and comprising a crescent-shaped blade comprising an external arcuate cutting edge and an internal arcuate undercut, the blade thickness decreasing in the radial direction outward, and is characterized by at least one of the following features:

the bevel of the cutting edge and the undercut are located on the same side of the blade; The blade thickness is reduced by a bevel running along the second side of the blade.

The invention proposes to provide both a bevel of the cutting edge and an undercut on the same side of the blade, and at the same time a conventional bevel of the blade on the other side.

Thus, the invention is in conflict with the conventional design, currently accepted in practice. The new cross-sectional shape somewhat resembles a propeller blade with a very small installation angle. During practical experiments, it turned out that with the use of a new shape of a cutting knife, the mass, in particular meat, in the cutter is not only better drawn in, but also better chopped. The mass is fed more intensively in the direction of rotation, while the knife is better stabilized in the direction of mass supply. Between the first and subsequent knives of the knife head, the mass is better compressed and fed to effective fine grinding. A separate cutter knife, leaving the mass, can no longer bend too much, which prevents its breakdown due to overload. The edge of the blade can be made thinner, and when rotated in the mass, it has less resistance. This, in turn, leads to a decrease in the required drive forces and to energy savings, for example, in the form of energy savings.

In addition, the above advantages are reinforced by the fact that the first side of the blade is at right angles to the axis, and the bevel on the second side of the blade is such that the thickness of the front of the blade adjacent to the cutting edge is greater than or equal to the thickness of the rear of the blade, turning into bevel. Such a knife is very effectively used as a so-called feed knife.

An embodiment of the invention provides that the first side of the blade extends at right angles to said axis, and the bevel on the second side of the blade is positioned so that the thickness of the front of the blade is less than the thickness of the rear of the blade that becomes undercut. Such a knife is very effectively used as a so-called retaining knife.

If the bevel is at least almost radial or at least rectilinear, then a simple end grinding machine is enough to obtain it.

If the bevel follows a sickle-shaped average curve, then to obtain it, you must use the appropriate controlled grinding machine.

In particular, when processing minced meat, etc. The emulsifying edge may adjoin the outer end of the cutting edge arc with an obtuse angle.

An arcuate cutting edge blade comprises a visible regrind region, a blade thickness in the regrind region is less than its thickness in the middle region, and the regrind region has at least almost parallel side surfaces.

The invention leads to the shape of the blade, which can be repeatedly, quickly and reliably sharpened to return sharpness and optimal shape when reaching or exceeding the permissible degree of wear. The formation of a thin regrind region first leads to the fact that when regrinding along the entire length of the arc of the cutting edge, a very small amount of material is removed from the blade, due to which the operation is accelerated, less heat is generated and the abrasives used are spared. Since the regrinding region is visually clearly limited due to its finer design, an unacceptable excessive regrinding of the blade is prevented, or at least immediately becomes apparent. Finally, the thinning of the blade in the region of the cutting edge and the accompanying shortening of the bevel of the cutting edge lead to a significant reduction in cutting resistance in the treated mass. This, in turn, leads to a reduction in energy consumption by the machine, which drives the corresponding knife head. In addition, the increased amount of heat generated on the cutting edge can be used.

If the width of the regrind area in the direction of the tip, for example, the emulsifying edge of the blade increases, it is necessary to take into account the fact that the wear of the cutting edge on the tip, as well as near it, is greater than in the area of the cutting edge located closer to the axis of rotation. This extension can be optimized if the width of the regrind area at least doubles.

To simplify manufacturing, it can be envisaged that the first side surface of the regrind region is a smooth extension of the second side of the blade, and the second parallel side surface passes through the transition region to the first side of the blade.

The transition region for various purposes can be performed in different ways. So, for example, it can consist of one step or smoothly pass into both side surfaces of the blade. In particular, when the shape is smooth, the transition region, at least mainly can be made smooth, convex, concave or in the form of a recumbent letter S, elongated in length. Smooth shape contributes to the work of the so-called retaining knife.

A particular embodiment provides for the presence in the transition region of at least one arcuate groove. The smooth transition region, as well as the transition region with one or more grooves, favor the braking action of the mass at the blade, i.e. contribute to the work of the so-called feed knife. One of the improved embodiments of the invention provides, in particular, the enhancement of this effect, so that the transition region contains two or more arcuate grooves located on one straight line, as well as in a convex or concave arc.

Such grooves can be arranged so that the number of grooves in the direction of the tip, for example in the form of an emulsifying edge of the blade, decreases. Similarly, it can be provided that the groove, or grooves, do not extend parallel to the blade.

One of the improved embodiments of the invention provides that the blade undergoes changes not only in the part of the cutting edge. It is proposed here that the inner arcuate back bevel of the blade consist of several parallel arcuate grooves. Such an implementation may contribute to the effect of undercutting.

The grooves in the transition region and / or undercut can be made the same or similar. So, for example, the cross section of the groove can be made arcuate and, in particular, in the form of a circular arc. The effect of the grooves depends on the size of the grooves and the ratio of these sizes. So, for example, the width of the groove may be several times greater than its depth, and adjacent grooves may be the same width and / or depth. Particularly favorable was the form in which adjacent grooves form points between themselves, located at an angle, preferably 90 ± 20 °.

Finally, the advantages of the invention can be used to a particular extent if the cutter head on which two or more knives are mounted are mounted on one common drive shaft, and at least one cutter knife is made in the form of the above feed or retaining knife.

It is particularly preferred that at least one knife in the cutter head is made as a feed knife and at least one knife as a retainer knife according to the aforementioned embodiment.

Other particular advantages, features and details of the invention will become apparent to those skilled in the art from the following description of embodiments of the invention. The invention is not tied to the shown type of attachment of the cutter knife, although the latter, preferably, can be used to install two knives in the same plane of the knife head.

Figure 1 depicts a side view of a cutter knife in a scale of approximately 1: 2,

figure 2 is a side view on the right of the cutter knife of figure 1,

figure 3 - the cutter knife in figure 1 after turning 180 ° around a vertical axis,

figure 4 is a section along the line IV-IV in figure 1, however, for clarity, the invention with a much greater thickness,

5 is a cross section of another cutter knife along the line V-V in figure 1, coinciding with the line IV-IV,

6 is a side view of a cutter knife in another embodiment on a scale of about 1: 2,

Fig.7 is a section along the line II-II in Fig.6 on an enlarged scale,

Fig.8 is a section along the line III-III in Fig.6 on an enlarged scale.

The cutter knife 1 contains a fastening section 2 in the form of a semicircle with a central hole 3 and with an axis of rotation XX and two centering holes 4 for installation on centering bolts not shown, as well as through holes 5. A sickle-shaped blade 6 of the knife is separated from the fastening section 2, on the outside which has a cutting edge 7 in the form of a part of a circular arc with a wide internal bevel 8 and a narrow external bevel 9. A relatively dull emulsifying edge 10 adjoins the outer end of the cutting edge 7 at an obtuse angle α. On the same visible first thoron 6 knife blade 11 is relatively blunt arcuate undercut 12.

Knife 1, in principle, is located at right angles to the axis of rotation XX. The first side 11 of the knife blade 6 is in the same plane as the side of the mounting portion 2 visible in FIG. 1. The mounting portion 2 and the beginning of the knife blade 6 have the same thickness D (see FIG. 2). On the second side 13 (see FIG. 3), starting from line 14, the blade 6 of the knife has a bevel 15 on which the thickness D decreases in the direction of the free end of the blade 6 of the knife, more precisely the beginning of the emulsifying edge 10, to a thickness D1 (see FIG. .2). The inclination of the bevel 15 extends or at least approximately radially to the axis XX, i.e. parallel to the diameter D-D line indicated in FIG. 1, or it follows at least about a sickle-shaped average curve 16, designated in FIG. 3 as an imaginary middle line by a dash-dot line, and in FIGS. 1 and 6 by a dash-dot line with two points.

In Fig. 1, S denotes a section of a knife blade 6. If the inclination of the bevel 15 follows the middle curve 16, then both sides 11 and 13 between the cutting edge 7 and the undercut 12, when viewed in the direction transverse to the inclination of the bevel 15, are preferably parallel.

Figure 4 shows a section along the line IV-IV in figure 1, but only with a certain form of execution of the bevel 15 ′. Moreover, only for clarity of the invention, instead of a thickness D corresponding to the scale (see FIG. 2), a significantly larger thickness D ′ is shown. The bevel 15 ′ here is inclined to the side 11 so that the front thickness Dv is obtained, which is larger than the rear thickness Dh of the knife blade 6. The expressions “front” and “back” here refer to the direction of rotation, respectively, to the cross section of the blade 6 of the knife. This form is used for the so-called feed knife, for which, however, the relation Dv = Dh can also be valid.

Figure 5 shows a cross section of another cutter knife corresponding to a section along the line IV-IV in figure 1. The bevel 15 ′ ′ here is inclined to the side 11 so that the front thickness Dv ′ is obtained, which is less than the rear thickness Dh ′ of the knife blade 6. This form is used with the so-called retaining knife.

The aforementioned feed and retaining knives in a known manner can be mounted in one knife head containing several knives. In such a knife head, the knives can be mounted axially both in the same plane and in different planes.

In particular, it becomes clear from FIGS. 4 and 5 that by means of bevels 15, 15 ′ and 15 ″, the cutter knife 1 can be shaped into a propeller or at least a shape similar to the latter. By varying the installation angle of this form of quasi-screw, the properties of the knife 1 according to the invention can be further optimized, in particular in accordance with the properties of the various processed masses. In accordance with this, various knives or whole knife heads can be kept ready in advance for processing very specific masses or made specially.

In another embodiment of the invention, the knife 1 between the cutting edge 7 and the middle region 108 of the blade 6 has a thinned regrind area 109 along the entire length of the cutting edge 7.

In Fig.7 in an enlarged view shows a section along the line II-II in Fig.6. Shows the cross section of the area 109 regrinding of the cutting edge 7 with a bevel Sn. The regrinding region 109 has a thickness Dn equal to about half the thickness Dm of the adjacent middle region 108 of the blade 6 and forms two parallel side surfaces 117 and 118. The first side surface 117 is located in the same plane as the bevel 15 on side 13, i.e. . it smoothly goes to side 13. At the same time, the second side surface 118 passes through the transition region 120 provided with grooves 119, to the side 11 of the blade 6. The grooves 119 have an arcuate cross section of the same width Br and the same depth Tr, and the width Br ′ several times greater than the depth of Tr. The grooves 119 are located on one straight line 121, indicated by a dash-dotted line, which connects the side surface 118 of the regrinding region 109 with the side 11 of the blade 6, and form an angle β between the tips 122 of approximately 90 °.

On Fig in enlarged view shows a section along the line III-III in Fig.6. In the region of the trailing edge 12 there is a series of grooves 123 parallel to each other, which can be made similar to grooves 118, between which, in particular, points 124 are formed. The grooves 123 extend into a blunt edge 125 bordering the bevel 15 of side 13.

List of items

1. cutter knife

2. mounting area

3. hole

4. centering hole

5. through hole

6. knife blade

7. cutting edge

8. bevel

9. bevel

10. emulsifying edge

11. first side

12. undercut

13. second side

14. line

15. bevel

fifteen'. bevel

fifteen''. bevel

16. middle line

108. area

109. regrind area

117. side surface

118. side surface

119. groove

120. transition area

121. direct

122. point

123. groove

124. point

125. hem

Bn1 width

Bn2 width

D thickness

D ′ thickness

D1 reduced thickness

Dh back thickness

Dh ′ back thickness

Dm thickness

Dn thickness

Dv front thickness

Dv ′ front thickness

S section

D-D diameter line

Sn bevel

Tr depth

X-X axis of rotation

α angle

β angle

Claims (32)

1. The cutter knife (1), installed by at least one flat fastening section (2) in the form of a part of a circle with the possibility of rotation around the axis (XX) and including a crescent blade (6), containing an external arcuate cutting edge (7 ) and an internal arcuate undercut (12), the thickness (D) of which decreases radially outward, characterized in that
a) the bevel (8, 9) of the cutting edge (7) and the undercut (12) are located on the same first side (11) of the blade (6);
b) a decrease in the thickness (D) of the blade (6) is due to the bevel (15) passing along the second side (13) of the blade (6). 2. Knife (1) according to claim 1, characterized in that the first side (11) of the blade (6) is located at right angles to the axis (XX), and the bevel (15) on the second side (13) of the blade (6) ) passes in such a way that the thickness (Dv) of the front of the blade (6) adjacent to the cutting edge (7) is greater than or equal to the thickness (Dh) of the rear of the blade (6) turning into undercut (12). 3. Knife (1) according to claim 1, characterized in that the first side (11) of the blade (6) extends at right angles to the axis (XX), and the bevel (15) on the second side (13) of the blade (6) ) is located in such a way that
the thickness (Dv ') of the front of the blade (6) becomes less than the rear thickness (Dh') of the rear of the blade (6), turning into an undercut (12). 4. The knife (1) according to one of claims 1 to 3, characterized in that the bevel (15) extends at least almost radially. 5. The knife (1) according to one of claims 1 to 3, characterized in that the bevel (15) follows a sickle-shaped average curve (16). 6. Knife (1) according to one of claims 1 to 3, characterized in that an emulsifying edge (10) is connected to the outer end of the arc of the cutting edge (7) with an obtuse angle (a). 7. The knife (1), installed by at least one flat mounting section (2) in the form of a part of a circle with the possibility of rotation around the axis (XX) and comprising a crescent blade (6) containing an external arcuate cutting edge (7) and an internal arcuate undercut (12), the thickness (D) of which decreases radially outward, characterized in that
a) the blade (6) for the arcuate cutting edge (7) contains the visible region (109) regrinding;
b) the thickness (Dn) of the blade in the regrind region (109) is less than the thickness (Dm) in the middle region (108) of the blade (6), and
c) the regrinding region (109) has at least almost parallel lateral surfaces (117, 118). 8. The knife (1) according to claim 7, characterized in that the width (Bn1, Bn2) of the regrinding region (109) in the direction of the blade tip (6) increases. 9. The knife (1) according to claim 8, characterized in that the width (Bn1, Bn2) of the regrinding region (109) is at least doubled. 10. A knife according to one of claims 7 to 9, characterized in that an emulsifying edge (10) is connected to the outer end of the arc of the cutting edge (7) with an obtuse angle (α). 11. Knife (1) according to one of claims 7 to 9, characterized in that the first side surface (117) of the regrinding area (109) is a smooth extension of the second side (13) of the blade (6), and the second parallel side surface ( 118) passes through the transition region (120) to the first side (11) of the blade (6). 12. Knife (1) according to claim 11, characterized in that the transition region (120) consists of at least one step. 13. The knife (1) according to claim 11, characterized in that the transition region smoothly passes into both side surfaces of the blade. 14. Knife (1) according to claim 12, characterized in that the transition region (120) is at least predominantly flat, convex, concave or in the shape of a recumbent letter S elongated in length. 15. The knife (1) according to claim 11, characterized in that the transition region (120) contains at least one arcuate groove (119). 16. A knife (1) according to claim 15, characterized in that the transition region (120) contains two or more arcuate grooves (119) located on one straight line (121) or on one arc. 17. The knife (1) according to clause 16, characterized in that the number of grooves (119) decreases in the direction of the edge of the blade (6). 18. Knife (1) according to clause 16, characterized in that the grooves (119) do not extend parallel to the cutting edge (7). 19. Knife (1) according to claim 7, characterized in that the internal arcuate undercut (112) consists of one or more parallel arcuate grooves (123). 20. Knife (1) according to clause 16, characterized in that the cross section of the groove (119) is made arcuate. 21. The knife (1) according to claim 19, characterized in that the cross section of the groove (123) is made arcuate. 22. The knife (1) according to claim 20, characterized in that the cross section of the groove is made in the form of a circular arc. 23. The knife (1) according to claim 20, characterized in that the width (Br) of the groove (119) is several times greater than its depth (Tr). 24. The knife (1) according to claim 20, characterized in that the adjacent grooves (119) have the same width (Br) and / or the same depth (Tr). 25. Knife (1) according to claim 20, characterized in that the adjacent grooves (119) form points between themselves (122, 124). 26. Knife (1) according to claim 24, characterized in that the tips (122, 124) form an angle (β) of 90 ± 20 °. 27. The cutter knife (1), installed by at least one flat fastening section (2) in the form of a part of a circle with the possibility of rotation around the axis (XX) and including a crescent blade (6) containing an external arcuate cutting edge (7 ) and an internal arcuate undercut (12), the thickness (D) of which decreases radially outward, characterized in that.
a) the bevel (8, 9) of the cutting edge (7) and the undercut (12) are located on the same first side (11) of the blade (6);
b) a decrease in the thickness (D) of the blade (6) is due to the bevel (15) passing along the second side (13) of the blade (6),
c) the blade (6) for the arcuate cutting edge (7) contains the visible region (109) regrinding;
d) the thickness (Dn) of the blade in the regrind region (109) is less than the thickness (Dm) in the middle region (108) of the blade (6), and
f) the regrinding region (109) has at least almost parallel lateral surfaces (117, 118). 28. Knife (1) according to item 21, characterized in that an emulsifying edge (10) is connected to the outer end of the arc of the cutting edge (7) with an obtuse angle (α). 29. Knife head, characterized in that it contains at least one cutter knife (1) according to one of claims 1 to 3. 30. Knife head, characterized in that it contains at least one cutter knife (1) according to one of claims 7 to 9. 31. Knife head, characterized in that it contains at least one cutter knife (1) according to claim 27 or 28. 32. Knife head, characterized in that at least one cutter knife (1) is installed in accordance with claim 2 or 3.

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