ES1073069U - Portable block cutter machine i.e. tile cutter, for use in construction site, has lever transmission mechanism with actuation levers rotatably integrated with small spindle, and two cam profiles cooperating with section of support plate - Google Patents

Abstract

Block cutting machine comprising a structural frame (1, 2, 3, 5) inside which a cutting blade (L) slides like a guillotine, remains elastically elevated and is capable of descending under pressure towards a support plane (4) by means of a lever transmission mechanism, said mechanism comprising at least one lever (12, 13), with fulcrum on an upper transverse element (5) of said frame in an off-center position, and a pin of thrust (9) that acts on said cutting blade (L) and is adjustable in a longitudinal position on a support plate (6), pivoting said plate (6) in a vertical plane with respect to said upper transverse element (5), characterized in that said actuation lever (12, 13) is integrated in rotation with a small shaft (10a) that has at least some first (10) and second (14) cam profiles that cooperate with a part (6a) of said pivoting plate (6). (Machine-translation by Google Translate, not legally binding)

Description

Block cutting machine.

Field of the Invention

This utility model refers to a improved block cutting machine, in particular, to a machine Block cutter with a laterally articulated lever.

State of the art

As is known, a cutting machine blocks is a portable machine, typically for applications in building sites, designed to cut small blocks of concrete or blocks of significant thickness, for example, components of exterior interlocking pavement blocks.

In order to perform this function, this machine it must be solid and allow the user to impart a pressure of significant breakage without requiring excessive effort Therefore, these machines typically comprise a pair of guiding posts parallels that rise vertically from a base, on whose posts are slidably mounted as a guillotine a Breaking blade with a wedge-shaped bottom edge. It does the blade descends steadily towards the guided base along of the posts until you find and cut a small block placed manually on the base as opposed to a lower blade correspondent.

The upper blade remains pushed towards Up by a spring system to automatically maintain Open the mouth of the guillotine and facilitate the introduction of pieces to cut. The opening of the guillotine's mouth is actuated by means of adjustment that determine the position of the blade with respect to the base in the starting position. Depending on the situation, the blade can be adjusted in height with adjustment means arranged between the blade and the element upper transverse of the machine or between the transverse element top - with which the blade is integrated - and the posts lateral. In the first case, a screw is typically provided large that fits with a corresponding threaded seat in the upper transverse element, thus being able to descend or rise depending on the screwing of the envelope the cross element. In the latter case, the two extremes of the cross element are provided with respective tabs threads that - by rotation - can slide vertically over The two posts. The latter way, despite constricting the blade to the transverse, upper element - what makes the construction be intrinsically more rigid - it is significantly more uncomfortable to maneuver

In order to impart the breaking action, It has a lever system that can be operated by the user when desired, moving the blade down in order to move it away of the upper transverse element of the machine.

So far, two have been proposed fundamental configurations for the pressure system by lever.

One of these configurations provides that articulate a drive lever in one position substantially medium (i.e. located transversely over the axis of symmetry of the guillotine structure) on the element upper transverse of the machine. On the same axis of joint is also arranged a cam that, by the rotation of the lever, push the cutting blade down.

The first system, which has been supplied in Different configurations, it is simple and quite economical. Further, as long as the cam profile is properly configured, this system causes significant blade travel even with small rotation angles of the actuation lever; by Therefore, it is possible to perform the cutting operation and the opening of the mouth through small rotation / displacement actions on the lever, which is easy for the operator to handle and allows perceive a productivity benefit. Conversely, a tour wide blade with a small lever travel implies an unfavorable transmission ratio and, therefore, forces operator to make a significant effort, unless he has a very long lever, which, however, is uncomfortable for others reasons.

To compensate for this inconvenience, it is theoretically necessary for the user to act on the lever of the standing machine - also using its own body weight on the lever - which is not entirely welcome by tilers, who are used to working near the ground, Often on your knees Therefore, operators use typically this "pulse" machine, that is, making the lever oscillates during subsequent short trips, exploding the kinetic energy that can be imparted to the lever and mechanism of transmission, to turn it into a series of pressure races on the blade that finally cut the underlying block in all cases.

However, this mode of operation forces to oversize machine elements to prevent faults premature, which is detrimental to the weight of it. In addition, the Drive-like drive introduces recoil races in the system that affects the operator's arm, possibly arising unwanted pathological conditions in the worker. Finally I know has detected that, with this technique, it is very difficult for them to cut blocks of mature concrete, that is, concrete that has been hardened particularly over time.

A second system instead provides for the appeal of articulate the lever on the cross member on one side of the machine, for example, in the vicinity of either posts, and then apply a transmission lever to a pressure element arranged centrally above the blade cutting

A typical machine of this type is represented by models art. 4th art. 6L offered in the market by the same applicant and also by the object of the Model International DM / 031555 and the Italian utility model No. 168,000

The operation of this machine is excellent and It does not require significant effort. Conversely, the system of transmission is more complex and requires a broad movement of the actuation lever to obtain a proper travel of the cutting lever

Actually, the travel limitation does not it implies a problem during the block cutting phase, since a very short travel with high pressure is usually necessary to break a concrete block. Instead, it represents a inconvenience during the phase of introducing blocks in the machine. In fact, since the weight or thickness of the blocks (especially if they are stone instead of cast concrete) you can vary also widely (2-4 mm) also inside from the same lot, it is necessary to ensure a good travel of opening of the guillotine structure whenever you need reposition a block on the base after it has been cut the previous block. Under these conditions, if it is required that the operator performs a wide rotation of the lever drive, an element of discomfort is introduced which is perceived as a slowdown in productivity or a burden of additional job.

A similar problem arises - with both types machine - when there is a short break in the sequence of cut; in reality, it is not possible to hold your mouth provisionally stable in its maximum opening position because, in that state, the operating lever does not remain in a position of stable balance (due to its own weight, it always tends to fall, closing the mouth of the guillotine, especially whenever employ rotating bearings and bronzes, which have an inertia and a very low friction). In these cases, the operator is forced to stand up and raise the lever completely - carrying it towards a stable starting position, normally bent towards back on the opposite side with respect to the operating side. This process of bending backwards of the lever is perceived as uncomfortable in a series of circumstances.

Finally, with the lever in a position of stable departure, an additional inconvenience linked to the machine setting.

Actually, in that posture, the lever is completely disengaged from the blade and the mouth of the guillotine is wide open, far exceeding the opening of the beginning of the break, that is, the opening that is determined when lever is returned to the correct posture for the action of Operator pressure

As a result, the height adjustment of the blade that can be set in these conditions is not optimal for working on the blocks. In essence, adjusting the opening of the guillotine's mouth with the lever bent back was a starting position should be set at a slightly wider value than necessary. Since this oversize measurement cannot be determined a priori, the following procedure must be taken functionally: the operator inserts a block into the mouth of the guillotine and adjusts the height of the blade leaving a wide gap (at least 2 cm, for example ) between the blade and the upper surface of the block; then, place the lever in a broken position and check if it is in close proximity to the block; if this distance is not observed, raise the lever again to a starting position and adjust the adjustment means again. In essence, with two or three attempts, the desired setting is obtained, but - as you can guess - to the detriment of a smooth action.

Therefore, the objective of this model is provide an effective solution to these problems by providing a block cutting machine of the second type that allows a significant travel of the cutting blade even with reduced rotations of the drive lever.

Summary of the invention

It is also intended to provide a machine block cutter in which the drive lever can staying in a stable starting position even with the mouth of the guillotine in an open position suitable for starting the breaking action.

These objectives are achieved through a block cutting machine as described - in its essential features - in the main claim attached.

Other inventive aspects of the machine block cutter are described in the claims subordinates

Brief description of the drawings

Other features and advantages of the machine depending on the model they will be more clearly shown in any case from the detailed description provided by way of example and illustrated in the accompanying drawings, in which:

Figure 1 is a perspective view of the block cutting machine according to the model;

Figure 2 is a front elevation view of the machine of figure 1;

Figure 3 is a side elevational view of the machine of figure 1;

Figures 4A-7A are side elevation views, with parts removed, of various operating phases of the machine of figure 1, of which

Figures 4B-7B are about expanded detail views, respectively;

Figure 8 is a perspective view of a small camshaft according to the model;

Figure 9 is a diagrammatic view of the profile of cam of the small tree of figure 8;

Figure 10A is a perspective view of the machine according to the model, from which

Figure 10B is an enlargement of the detail enclosed in circle A; Y

Figure 11 is an enlarged view of a phase of cam operation according to the model.

Detailed description of an embodiment of the invention

A block cutting machine comprises, of in a manner known per se, a base beam 1 from which they leave two parallel vertical posts 2 and 3 among which is arranged a support plane 4 at the bottom.

The base beam 1 may also be provided of a pair of crazy wheels W1 and W2, suitable to improve the machine portability.

On top of posts 2 and 3, it is arranged a fixed transverse element 5 parallel to the plane of support 4.

Advantageously, each of posts 2 and 3 it comprises a pair of beams 2a, 2b and 3a, 3b, respectively, arranged at a short distance from each other to define a track of sliding for a top-cut blade L mounted in shape vertically sliding along the posts.

The blade L is shaped like a plate elongated rectangular, with a wedge-shaped bottom edge, held in parallel to the support plane 4. Blade L is kept pushed in an elevated position by elastic means (not shown) housed between each of the two pairs of beams 2a, 2b and 3a, 3b.

Below the cutting blade L is arranged a lower support counter knife R having an edge wedge-shaped upper substantially flush with the plane of support 4. The support counter knife R remains fixed secure to base 1 and posts 2 and 3 to act as support safe for blade L during block cutting concrete.

In order to make room for the counter knife R, the support plane 4 is divided into two trays 4a and 4b mounted cantilever on both sides of the plane that passes through the posts 2 and 3. At least one of the two trays, the left 4th in figure 2, it is preferably arranged so that it is projected down to an inclined position so they can beveled cuts in the blocks (bevels) facilitate the placement of blocks in certain circumstances).

The upper transverse element 5, as well as the side posts, in turn comprise a pair of parallel bars 5a and 5b fixed on the outside of the two posts 2 and 3 and, therefore, arranged at a distance from each other to leave a receptacle that houses a transmission mechanism. Such mechanism - how can look better in figures 4B-7B - comprises a metal plate 6 articulated on beam 5 by a bolt pin 7 which crosses the two bars 5a and 5b from end to end.

Plate 6 is free to rotate around the pin pin 7. In the central area, it presents a core part 8 provided with a threaded through hole arranged to fit substantially on the central axis of the transverse element 5. A threaded pin 9 engages with the threaded hole of the core 8, entering and leaving the corresponding holes drilled in the plate 6.

The threaded pin 9 has a button upper drive 9a and a rounded bottom end 9b suitable for coming into contact with the blade L or with a plate of support L_ {1} thereof. The same being the position of the plate 6, screwing or unscrewing the threaded pin 9 determines an elevation or descent of the blade L - which is pushed elastically upwards - and therefore defines a setting of the opening of the guillotine's mouth, that is, the distance between the two wedge-shaped edges of the upper blade L and of the counter knife R.

Depending on the model, plate 6 has a part of thrust 6a on which a cam 10 rotates around an axis of a tree 10a supported transversely with respect to the cross member 5 on suitable bearings 11.

Tree 10a has two ends that are extend on both sides of cam 10, as shown clearly in figure 8. in figure 9 (which is a view diagrammatic of the cam profile of the small tree of figure 8) is identify with the PAR reference the foothold of "break", with the PAA reference the foothold of "adjustment", with the reference PAAM support point of "opening maximum "and with the PAAF reference the support point of "force application".

The two ends of the tree are supported on the two bearings 11 (mounted on the two parts 5a and 5b of cross element), leave the two opposite sides of the element transverse 5 and are integrated with a drive lever 12. Although the operating lever 12 may be integrated in rotation also with an outer end only of the tree 10a, with in order to better balance the efforts on the machine is it is preferable that the lever is attached to both external ends of the 10th tree To that end, the lever 12 has a part of fork arranged outside beam 5 and posts 2 and 3 corresponding, which is then attached to a single handle 13 on which is intended to operate the operator.

As an example, to get hold of the lever 12 to the tree 10a, said tree has ends square section machining to which a corresponding clamp 12a (see figure 1) of the lever 12.

As can be seen in Figures 4-7, cam 10 has an original profile designed with a double objective. On the one hand, it grows sharply (high radial gradient) by varying the angle of rotation to determine a wide path over a relatively small rotation arc: as an example, over a circle arc of approximately 30 ° (that is, in the passage of the force application start posture
- figures 4A and 4B - to the breaking position - figures 5A and 5B) the profile increases radially approximately 10 mm. On the other hand, the cam is positioned on the shaft 10a, so that it has a point of support on the thrust nail 6a as close as possible to the fulcrum axis in the direction parallel to that of the lever 12: this fact it allows to have a small force arm (between the axis of rotation of the shaft 10a and the point of support of the cam on the part 6a) and, therefore, a lever arm (second class lever) to advantageously exert the desired pressure In other words, the distance between the support point of the cam 10 on the nail 6a of the plate 6 and the axis of rotation of the shaft 10a should always preferably be shorter than 5 mm, considering such distance calculated along the axis of application of force on the lever 13 (that is, the line that joins the axis of rotation of the shaft 10a to the point of application of force on the handle 13). The angle α (figure 11) formed between a vertical axis EV and the line that joins the support point to the center of rotation of the cam is defined so that it is small, for example less than 30 °.

From this point of view, it should be taken in Consideration that cam 10 does not act directly on pin 9 to determine the thrust pressure on the blade L, but acts through the additional lever built by plate 6 around fulcrum 7 (again a second class lever), what which makes the lever ratio even more advantageous.

With an adequate sizing of the cam 10 and the distance between it and the fulcrum 7, it is possible to define a transmission mechanism that, in addition to an excellent lever arm, provides a good travel of the pin 9 - and, therefore, of the blade
L - even with modest rotation angles of cam 10.

According to an original aspect of this model, on the cam shaft 10a a second profile 14 of cam, substantially opposite to the first, capable of cooperating with the part 6a of the plate 6 in a stable starting position of the lever 12. In essence, when the lever bends backwards approximately 100º from its ordinary operating position (Figures 6A and 6B), it is placed in a stable position due to that its center of balance shifts to the opposite side of the bearing shaft 11 (that is, to the left of the bearing on the drawings) and pushes it until it rests against a stop. In this lever position, cam profile 14 engages with the part 6a. This cam profile 14 is designed to move the plate 6 to the same extent that it travels in the start phase of the breakage, that is, the one illustrated in figures 4A or 4B: in this position, the mouth of the guillotine is not completely open (as illustrated in Figures 7A and 7B, that is, in the posture in which the introduction of the blocks in the mouth of the guillotine runs smoothly), but is in the ideal position to adjust the blade height L in relation to the block height of sample B.

In all other intermediate positions of the lever L there is no raised cam profile acting on the part 6a and, therefore, the plate 6 remains in its highest position, pushing to it by the elastic means that push towards also the blade L, causing maximum opening of the Mouth of the guillotine.

According to an additional original aspect of the present model, between the upper cross member 5 and the fork 12 elastic thrust means are arranged said means are intended to act between the fork 12 and the cross member 5 to determine an upward push that compensates substantially the fork weight, preferably with a elastic push up proportional to the measure of rotation of the lever. To that end, as can be seen in the figures 10A and 10B, the elastic means are shaped like a spring in spiral 15 that works with torsion: the greater the rotation down the lever 12, the greater the elastic reaction of the spring 15.

Therefore, a return force is determined which is calibrated to drive the lever back to a position of incipient cut (figure 4A), or higher, when released from the breaking position (figure 5A). Functionally, this is translates into an advantage for the operator who, at the end of each breakage, it is not necessary to support the lever 12, but it can abandon her and, in any case, find her again - after the subsequent break - in a position where you define an opening suitable for the guillotine mouth for the introduction of the block next.

This arrangement allows the lever to be keep stable even in a position with the mouth of the substantially open guillotine, freeing the operator from having to necessarily move the lever to the other stable position completely bent back as illustrated in the figure 6A.

As can be stated by the description previously provided, the machine according to the model allows perfectly achieve the objectives set in the comments Preliminary Actually, the combination of the two levers of second class in the cam transmission mechanism allows get a good ride, although with lever rotation angles modest, while ensuring a pressure transfer effective on the blade with reduced effort by the operator. The presence of a second cam profile on the tree Lever transmission allows you to define - even with the lever in a stable starting position - the correct opening of the mouth - incipient cutting position of the blade - to be able to make the height adjustments of the upper moving blade.

Finally, due to the disposition of elastic pushing means, it is possible to keep the blade in the position of maximum opening of the mouth without having to support the lever with hand.

However, it is understood that the protection of Model described above is not limited to the configuration particular shown, but extends to any other variant of construction that achieves the same utility.

Claims (6)

1. Block cutting machine comprising a structural frame (1, 2, 3, 5) into which a cutting blade (L) slides like a guillotine, remains elastically elevated and is able to descend under pressure towards a support plane (4) by a lever transmission mechanism, said mechanism comprising at least one lever (12, 13), with fulcrum on an upper transverse element (5) of said frame in an off-center position, and a spindle of thrust (9) acting on said cutting blade (L) and is adjustable in a longitudinal position in a support plate (6), pivoting said plate (6) in a vertical plane with respect to said upper transverse element (5) , characterized in that said actuation lever (12, 13) is integrated in rotation with a small shaft (10a) having at least some first (10) and second (14) cam profiles that cooperate with a part (6a) of said pivoting plate (6). Machine according to claim 1, characterized in that said first cam profile (10) determines the maximum displacement of said pivot plate on an arc of rotation less than 90 ° and cooperates with said part (6a) of the pivot plate (6) in A phase of cutting pressure. Machine according to claim 1 or 2, characterized in that said cam profile (10), in the maximum opening position of the cutting blade (L), rests on said plate part (6a) at a point close to a vertical line Machine according to any of the preceding claims, characterized in that said second cam profile (14) cooperates with said part (6a) of the plate (6) in a condition in which the operating lever (12, 13) is in a stable starting position and bent backwards. Machine according to claim 4, characterized in that said second cam profile (14) is suitable for determining a displacement of said pivoting plate (6) in an extension such that said upper blade (L) descends to an incipient cutting level, suitable for defining a height adjustment of said blade (L) by means of said adjustment pin (9). Machine according to any of the preceding claims, characterized in that, in addition, elastic thrust means (15) are arranged between said actuating lever (12, 13) and said upper transverse element (5), capable of supporting said lever in a state such that the upper blade (L) is raised, the elastic support action of said elastic pushing means (15) being able to be overcome by the application of a downward force on said lever (12, 13).