EP2828048B1

EP2828048B1 - Arm of a sawing machine for sawing ornamental stones

Info

Publication number: EP2828048B1
Application number: EP13712166.1A
Authority: EP
Inventors: Luigi Fantini
Original assignee: Fantini Sud SpA
Current assignee: Fantini Sud SpA
Priority date: 2012-03-21
Filing date: 2013-03-08
Publication date: 2016-05-11
Anticipated expiration: 2033-03-08
Also published as: ITRM20120105A1; ES2586597T3; WO2013139632A1; EP2828048A1; PT2828048T

Description

Field of the art

The present invention refers to a sawing machine for ornamental stones such as that used in quarries in order to execute horizontal, vertical cuts etc. More in particular, the invention relates to an orientable arm of a sawing machine according to the preamble of claim 1, around which the cutting chain rotates, which comprises links, inserts, insert holders etc.
Even more specifically, the present invention relates to lateral guides of the cutting chain of the sawing machine, which comprise a plurality of separate pieces or modules.
Prior art
Such an arm is to known from FR 2 496 544 A1 .
The known lateral guides of the cutting chains of chain saws comprise various substitutable pieces mounted on both sides of the body of the arm, along the edges of the latter. This due to the fact that a deformation or breakage on one side of the lateral guide would otherwise require the substitution of the entire guide (loss of time, waste of material, etc.). The cutting chain therefore slides, actuated by the drive pinion placed at the proximal end of the sawing machine arm, between said lateral guides and on the horizontal base of the guide, where there are various parts subjected to wear, the same also being removable/substitutable but do not form part of the present invention.
The abovementioned pieces of the lateral guides are mounted by means of suitable fixing means to the edge of the main body of the arm. Normally, the fixing means are screws which are screwed in the threaded holes arranged along the edge of the sawing machine arm. The pieces of the lateral guides do not overlap each other; at most, they mate, giving rise to a butt joint.
Since the pieces of the lateral guides constitute wearable materials, it is not convenient to push the manufacturing to the level of extreme precision (the pieces are worn by friction and must be repeatedly substituted). Therefore, small air spaces almost always remain between the pieces (at the joints thereof), from which considerable quantities of chain lubrication grease exit outward.
Though environmental-friendly, the grease dispersed in the environment, through said air spaces or interstices between the pieces, creates problems from the economical standpoint. Lesser grease in the circuit leads to a greater wear of the chain, lower efficiency etc.
An object of the present invention is to attain an orientable arm (for sawing machines with cutting chain) equipped with a modular lateral guide such to prevent the outflow of grease between the various pieces or modules of the lateral guide.
Another object of the present invention consists of maintaining the assembly costs regarding the pieces, the fixing means (screws) and the assembly technique substantially unvaried. The only variation lies in the shape of the pieces, which can nevertheless continue to be machined without excess precision.

Brief description of the invention

The present invention is defined by the features of independent claim 1. Further preferred embodiments are defined by the features of dependent claims 2-9.
In practice, by using also the same wearable material and the same assembly technique, e.g. screws (the number thereof is variable for example as a function of the length of the piece), this leads to an overlap at the ends of the various pieces, at the joint; such overlap does not oblige the producer of such pieces (of the lateral guide) to meet extremely precise tolerances. On the contrary, the overlap can be verified, within certain limits; in other words, there can be a certain "clearance" within which the overlap ensures a good seal for the lubricant grease.
The preferred embodiment of the pieces of the lateral guide consists of plates whose ends have step-like surfaces, or better yet surfaces separated by a step, wherein the surface associated with a reduced thickness of the plate/piece comes into contact (in assembly position) with the corresponding surface (associated with a reduced thickness) of the adjacent plate/piece.
It is important to observe two things: 1) The reduced thickness portions which are overlapped with each other at the joints are not affected by the fixing screws and remain free in order to create a contact "with flat surface" and with a certain pressure force which reliably prevents the passage of the lubricant grease towards the external of the guide. 2) The total thickness of each lateral guide is constant and does not vary with respect to the prior art. Said d₁ and d₂ are the thicknesses of the single small plates in the mutual overlap zones, and said "D" is the total thickness of the guide that corresponds with that of the prior art, i.e. d₁ + d₂ = D holds true. Preferably d₁ = d₂ = D/2.
Said steps (one for each of the two ends of the piece) can be formed on the same side of the piece, or on opposite sides of a same piece. More than one step can also be provided for at each end. This creates a zigzag path (more difficult for the lubricant to pass beyond, but involving more complex machining).
Other embodiments do not exclude an overlap of linear type (i.e. along a line) between two contiguous pieces of the lateral guide, and/or other shapes of the piece.
It is essential that the overlap zones ensure a reliable watertight seal without complicating the assembly and/or the machining costs in an unsustainable manner.

Brief description of the drawings

The present invention will now be illustrated in more detail and in its various aspects, through various drawings in which it is represented:

FIGURE 1 shows the overall view of the sawing machine arm according to the present invention;
FIGURE 2 shows the side view of the arm shown in Fig. 1, omitting various components including the drive pinion, the small transmission wheel, the cutting chain, etc.;
FIGURE 3 shows a view analogous to Fig. 2 but without the improvement introduced by the present invention at the lateral guides (prior art);
FIGURE 4 shows a side view of only the lateral guides of one side of the arm, according to the present invention;
FIGURE 5 shows a side view analogous to Fig. 4 but relative to the lateral guide of the prior art;
FIGURE 6 shows one of the two flanks of the arm, for protecting and assembling the small idle transmission wheel placed at the free end (according to the prior art);
FIGURE 7 shows one flank of the arm, for protecting and assembling the small idle transmission wheel placed at the free end (according to the present invention);
FIGURE 8 shows the sections (at the joint) of various possible innovative embodiments of pieces or small plates of the lateral guide, which show the overlap of such pieces or modules of the lateral guide of the cutting chain for preventing the outflow of the lubricating grease;
FIGURE 9 shows a comparison between two possible embodiments with a single step (rectilinear profile on the left and curved profile on the right) for a single piece or module of the lateral guide of the present invention;
FIGURE 10 respectively shows a side view and a sectional view of a module or small plate of the lateral guide according to the present invention, in the preferred embodiment, with rectilinear step;
FIGURE 11 shows a module/small plate of the prior art (side view and sectional view, respectively);
FIGURE 10a shows a view analogous to that of Fig. 10, but in even larger scale;
FIGURE 11a shows a view analogous to Fig. 11 but in enlarged scale (prior art);
FIGURE 12 shows (prior art) an entrance module for the lateral guide;
FIGURE 13 shows an entrance module for the lateral guide, according to the present invention;
FIGURE 14 shows the entrance module of Fig. 13, in enlarged scale;
FIGURE 15 shows the butt joint between the module of Fig. 11 and the entrance module of Fig. 12 (for the prior art);
FIGURE 16 shows the overlap joint between the module of Fig. 10 and the entrance module of Fig. 13, according to the present invention;
FIGURE 17 shows a summary of the various components of the sawing machine arm with chain, according to the prior art and according to the present invention, respectively, and specifically:
FIGURE 17a shows the flank for protecting and assembling the small wheel, according to the prior art (5) and according to the present invention (15), respectively;
FIGURE 17b shows the innovative lateral guide entrance;
FIGURE 17c shows the lateral guide entrance of the prior art;
FIGURE 17d shows an intermediate lateral guide module (prior art, see Fig. 11 and Fig. 3);
FIGURE 17e shows an intermediate lateral guide module (left) according to the invention (see Fig. 2);
FIGURE 17f shows an intermediate lateral guide module (right) according to the invention (see Fig. 2).

Detailed description of some embodiments

Some possible embodiments of the present invention will now be described. As stated above, the invention is applicable to arms of any type, not only that illustrated in Fig. 1.
The arm of a sawing machine with cutting chain employed in quarries of ornamental stones has an elongated and substantially flat form (for example about 3.8 cm maximum thickness), with a drive pinion 100 of the chain mounted on a support of the machine (not shown) as is evincible from Fig. 1. The free end 101 of the sawing machine arm bears a small transmission wheel 102 mounted on a bearing. The cutting chain 103 slides between the lateral guides 104 (in the upper part of the arm the lateral guide 104 was omitted in order to render the chain 103 at the back visible), around the perimeter of the arm and around the drive pinion 100 and the small transmission wheel 102. The base of the guide (groove) of the cutting chain comprises a plurality of substitutable wearable piece made of metal (also hard metal) clearly visible in Fig. 1, where the upper branch of the chain slides (i.e. where the lateral guide 104 was omitted in the drawing).
The cutting arm comprises (see also Fig. 2) a flat main body 1 with elongated form that is extended substantially from the drive pinion 100 up to the small wheel 102 (free end 101), i.e. respectively from the end of the main body indicated with 1' up to that indicated with 1" (the latter is shown dashed, since it is hidden by a flank 15 in this side view of Fig. 2).
The main body 1, as is known to men skilled in the art, has step-like edges for the assembly of the lateral guides, which in the prior art constitute various modules or pieces in small-plate form 3 fixable by means of screws 4 (two or three normally) to the main body 1 along the step-like edge thereof. This is clearly shown in Fig. 3 (prior art). In the part of the arm of entrance/inlet for the chain (drive pinion side), there are two (preferably four, if one also considers the opposite side of the arm not visible in the side view) entrance modules or pieces 3i which form an angle with a respective final intermediate guide module 3. For the present invention, it is essential to observe once again that the joints between two pairs of contiguous modules (3, 3) and (3, 3i) of the prior art constitute "butt joints" 3-3 or 3-3i, which for the abovementioned reasons create interstices, where the lubricant grease easily finds an outflow route. The present problem also arises in the prior art (Fig. 3), also at the joint between the so-called flank 5 and the intermediate lateral guide pieces 3. At this point, on each side of the main body 1, a respective step is provided for assembling a corresponding flank 5. Between the two flanks (5, 5), the small wheel is mounted (not shown in Fig. 3) with the relative bearing 6. The butt joint indicated with 7 in Fig. 3, between the components 5 and 3, creates the same problems relative to the outflow of lubricant grease through the interstice.
These problems are resolved according to the preferred embodiment of the present invention by employing particular lateral guide modules and particular flanks, indicated in Fig. 2 with 2d and 2s ("d" and "s" stand for right or left) and with 15.
Specifically, without having to modify the assembly technique (screws 4), the materials (wearable materials), or increase the working precision of the modules of the lateral guide (and of the flanks) with respect to the prior art, and without increasing the total thickness of the lateral guide itself, the present invention proposes using step-like modules or pieces that can be overlapped, which leave a certain clearance in order to make it possible to achieve an easy assembly (and hence without pushing to the extreme the working precision); this creates a contact between the surfaces of the steps of the adjacent pieces, such to prevent (also due to the pressure exerted by the fastening of the screws 4) the outflow of the lubricant grease from the guide groove of the chain.
Several possible specific embodiments of the lateral guide modules (or pieces) according to the present invention will now be illustrated.
In Fig. 9, on the left side, in Fig. 10, and in the enlarged scale view of Fig. 10a, there is illustrated the preferred embodiment of an intermediate guide module according to the present invention. Fig. 9 only shows a terminal portion, in perspective view, of the intermediate module 2d (or 2s) of the present invention. The holes (flared) for the screws 4 have been omitted here in order to simplify the drawing, but they are instead indicated with the reference 9 in Figs. 10 and 10a. The module 2s or 2d has the shape of a plate with the ends that form a step. In this preferred embodiment, the steps 10a and 10b are formed on opposite sides (faces) of the module and two modules of this type are flanked and mounted in a manner so as to at least partly overlap the surfaces "A" and "B" of such steps. The precision of the processing does not have to be pushed to the extreme, and the tolerances of the surfaces (A ± ε, B ± ε) can be selected in a manner so as to ensure low costs and a sufficient overlap.
By tightening the screws 4, the pressure on the surfaces "A" and "B" in mutual contact will prevent the outflow of the lubricant grease.
Of course, other forms are possible for the (intermediate) modules of the lateral guide, although they are less practical since more difficult to obtain. The form shown in the right part of Fig. 9 is curved rather than rectilinear, so that also the surfaces A or B are no longer rectilinear. Of course, in this case, the other end of the module - indicated herein with 2d(1) or 2s(1) -, not shown, must be complementary and hence concave in order to mate with the end shown but relative to the adjacent module. Also in this case the two step-like surfaces A - B are overlapped, creating a "surface on surface" joint" that prevents the outflow of lubricant grease.
Other possible embodiments for these lateral guide pieces according to the invention are schematically shown in sectional view in Fig. 8. The configuration "1" corresponds to that already discussed, the form "2" is that with double step (zigzag path, difficult for the lubricant grease to pass beyond and with two pairs of contact surfaces A, A' and B, B'), the forms "3", "4" and "5" instead require a lateral (longitudinal) fitting insertion between two close modules. The modules were all indicated with 2d in Fig. 8 for the sake of simplicity, but of course they could correspond with the left lateral guide and hence constitute the modules 2s.
All these embodiments shown in Fig. 8 correspond with a rectilinear joint, but there could also be combinations between the embodiments of Fig. 8 and the embodiment of Fig. 9, right side (curvilinear joint).
Regarding Figs. 2 and 7, these illustrate a modified flank 15, according to the present invention. The flank 15 is visible in the side view of Fig. 2 and it is screwed (by means of screws inserted in the holes 16) to one side of the main body 1 (close to the end 1"). Another flank 15 identical thereto is clearly found on the opposite side of the main body 1. Between these flanks 15, 15, the small transmission wheel of the cutting chain is mounted by means of the bearing 6 (shown only schematically).
Unlike the flank 5 (Figs. 6 and 17a on the left) of the prior art, the flank 15 of the present invention does not have an entirely rectilinear edge 5a, but rather has two recesses 15' and 15" on its edge 15a (rectilinear), which form a respective step cooperating with the step-like ends of the contiguous module 2d (2s) described above (see Fig. 2). In this case, the final intermediate module 2d (2s) is only shorter with respect to the other intermediate modules 2d (2s).
In Figs. 2, 13, 14 and 16, there is instead observed the shape that the lateral guide module (or piece) according to the invention assumes in the zone contiguous to the drive pinion. In this case, the module, so-called entrance module 2i (right or left, same symbol used in Fig. 2) has a step-like oblique side 17 for mating with the adjacent step obtained on the intermediate module 2s (or 2d). Also other forms could be provided for (see Fig. 8) as regards the joint 18 in Fig. 16.
Other embodiments/types of cutting arms, in which the lateral guide of the cutting chain can form a deviation, could comprise modules with oblique end as in Fig. 13.
Only for the sake of descriptive completeness, it can be observed that the rectangular notch 19 in Fig. 13 obtained in the entrance module 2i belongs to the prior art; this acts as a seat for a scraper (rubber prism with steel blade) that by pressing on the side of the chain, prevents the debris from reaching the drive pinion and damaging it.

Claims

Arm, preferably orientable, of a sawing machine with cutting chain (103) for the cutting of preferably ornamental stones in quarries, in order to execute for example horizontal and/or vertical cuts, comprising a main body (1), at least one drive pinion (100) of the chain connectable by means of a support to the sawing machine, at least one small idle wheel (102), preferably placed at a free end (101) of the sawing machine arm, wherein along the external peripheral edge of the main body (1) of the sawing machine arm, on both sides of this elongated flat arm, respective lateral guides (104) of modular type are provided, comprising a plurality of lateral guide pieces mounted on the main body (1) of the sawing machine arm in a removable manner and side-by-side, preferably contiguous at the ends, characterized in that said lateral guide pieces determine, during the assembly on the sawing machine arm, a contact overlap zone (A - B) at their ends and between each pair of contiguous lateral guide pieces, and such zone prevents a lubricating means from exiting between the flanked ends of the pieces, and in that the thickness of the lateral guide (104) is not increased due to these overlaps but remains rather substantially constant.
Arm of a sawing machine with cutting chain (103) according to claim 1, characterized in that said lateral guide pieces are mounted in a removable manner by means of fastening means (4), e.g. screws (4), which cross through holes (9) of the lateral guide piece, and threaded holes alignable therewith obtained on the main body (1); and in that the fastening force transmitted by these fastening means (4) to said contact overlap zone (A- B) contributes to preventing the outflow of the lubricating means from the lateral guides (4).
Arm of a sawing machine with cutting chain (103) according to claim 1 or 2, characterized in that said lateral guide pieces comprise rectangular plates (2s; 2d) with step-like ends (10a, 10b) determining overlap surfaces (A, B) between contiguous pieces on these step-like ends, without however increasing the total thickness (D) of the lateral guide (104).
Arm of a sawing machine with cutting chain (103) according to claim 1, 2 or 3, characterized in that said lateral guide pieces can have variable length with respect to each other.
Arm of a sawing machine with cutting chain (103) according to any one of the preceding claims, characterized in that a lateral guide piece (2i) can form an angle with respect to an adjacent lateral guide piece (2s; 2d).
Arm of a sawing machine with cutting chain (103) according to any one of the preceding claims, characterized in that the lateral guide pieces also comprise two flanks (15, 15) for assembly and protecting the small wheel (102), which are fixed to the main body (1) of the sawing machine arm on respective sides thereof, and which have overlap zones (20, 20) with the adjacent modules (2s; 2d), adapted to prevent the outflow of the lubricating means.
Arm of a sawing machine with cutting chain (103) according to claim 6, characterized in that in said overlap zones (20, 20), each flank (15) has step-like recesses (15', 15") which are overlapped with the step-like zones (10a, 10b) or at their surfaces (A; B).
Arm of a sawing machine with cutting chain (103) according to any one of the preceding claims, characterized in that the lubricating means fed into a lubricating means feed circuit is an ecological lubricating means.
Arm of a sawing machine with cutting chain (103) according to any one of the preceding claims, characterized in that the size of the contact overlap zones (A, B) is selected in a manner such that the working tolerances "ε" in any case ensure a sufficient contact surface between the contiguous pieces, without having to push the working precision to the extreme.