Oil submerged driving system with adjustable guide controlled drive for operating double knives cutter bars

Abstract: An oil submerged driving system with adjustable guide controlled drive for operating double knives cutter bars is contained in a box-like container and includes main control means (B), pivoted to the box on an axis (H), perpendicular thereto. The main control means (B) are connected, with a first working end, situated inside the box-like container, to actuating means (A), and with a second working end, situated outside the box-like container, to a first cutter knife (C) of the knives. The control means (B) are driven, by the actuating means (A), into alternate oscillation on the axis (H), so as to drive the first knife (C) into reciprocation. The transmission system includes connection means (E,G), supported by the box-like container, and linked to the main control means (B) at the first inner working end and connected to a second cutter knife (D) of the knives. The connection means (E,G) are operated by the main control means (B), so as to drive the second cutter knife (D) into reciprocation in direction opposite to the reciprocation of the first cutter bar (C).

Description: The object of the present invention is to propose a simple and efficient driving system according to the preamble of claim 1 for operating the second cutter knife of a double knife bar, which features all the advantages obtained by including all mechanical means in an oil (or grease) bath within a gearbox. Description of the prior art The double knife bars require mechanical operation capable of performing a reciprocating motion of the two cutter knives, in opposite directions. The advantages thus obtained are the following: 1) vibrations reduction (for operator's health protection as a prior aim). The stresses resulting from deceleration - acceleration of the first knife, when it reaches the stroke limit stop, are contemporary with the stresses of the second knife and have opposed sign. The obvious result is reciprocal compensation with reduction of the value resulting from the stresses; 2) increase of the relative speed of the knives with the same rpm speed on the power takeoff. This allows a better cut, smaller wear and fewer stresses. On the other hand, it is obvious that a mechanism which operates two knives instead of only one, is mechanically much more complicated and fragile than a mechanism which operates only one knife. Various kinds of operating mechanisms have been proposed so far, which present different disadvantages,. Some of them were described in our Patent No. 01295653 granted on May 24, 1999. The experience gained up to now demonstrate that, independently from the kind of the mechanism, problems mainly result from the difficulty to maintain efficient a mechanism, which often is not properly lubricated, due to negligence or forgetfulness, and which is subjected, during operation, to action of powder, soil and different agents present therein. It is possible to resolve most of the above problems by submerging the mechanism into an oil bath, within the gearbox. However, this solution appeared extremely cumbersome also due to the system complexity: the rotary motion derived from the power takeoff is oriented crosswise to the knives sliding axis, by means of a bevel gear pair. Two eccentric pins arranged on the driven gear operate two levers, formed by more parts, pivoted on a common axis. The result is the alternate oscillating motion of the two levers, in opposite directions, so as to operate the two knives on the bar. Although extremely efficient, the above described system has not been widely used, because of high construction costs. The present invention resolves the problem of matching the reliability of the oil bath system to the use of a mechanism as simple as possible by an oil submerged driving system as characterized in claim 1. Further advantageous arrangements and developments of the invention appear from the dependent claims. The enclosed drawings 1 to 3 show an oil submerged driving system with only the lower knife, for sake of explanation. Actually, the use of one or more elements, the so-called drive control guides, connected with the second knife by a suitably shaped element and guided through suitable seats made in the oil bath gearbox, allows to obtain the movement of the second knife from the rear part of only one pivoted lever, which results in the following advantages: 1) Extreme simplification of the mechanism, which results in the considerable reduction of the number of the mechanical elements necessary for the mechanism to operate. Consequently, the costs are significantly reduced. 2) The guided drive system allows to operate the second knife also if the driving member is very far (otherwise impossible). Actually, the whole of elements formed by the drive control guides and the connecting particular, acts as a knife head, yet, its wearing points are immersed in oil, which constitutes an absolute innovation. 3) All the remaining wearing areas are immersed in the oil within the gearbox. Thus, these parts are protected and lubricated. 4) It is possible to adjust the clearances formed between the lever and the drive control guides. Operating mechanism: (Figure 1) an eccentric shaft (particular A) transfers the rotary motion from the power takeoff to a lever (particular B) pivoted on the axis H inside the gearbox. The oscillation obtained on the fore end of the lever drives the first knife (particular C) into reciprocation. The rear end of the lever drives the second knife (particular D) to move in the opposite direction. It is to be noted that the size and the distance between the rear part of the pivoted lever and the bar, would make it impossible to operate the knife to slide on a determined axis, if seats (particular S) were not made in the gearbox (Figure 2). The seats (particular S) control the sliding of drive control guides (particular E) which are pushed by the lever oscillation and transmit the motion to the second knife by the connecting element (particular G) without any misalignment of the second knife. It is to be pointed out that the whole formed by the connecting element and the drive control guides acts as a knife head and that its wearing parts are immersed in oil. The above described solution is an absolute novelty. The possibility to adjust the clearance between the lever (particular B) and the drive control guides (particular E) by stud bolts (particular F) and relative screw nuts ensures not only the indispensable lubrication by the oil contained in the gearbox, but also the system functionality and efficiency. Figure 3, added for clarity, shows, in the right half part, a possible embodiment of the connecting element, situated under the oil bath gearbox.

Claims: Oil submerged driving system with adjustable guide controlled drive for operating double knives cutter bars, the system being contained in a box-like container and including main control means (B), pivoted on said box-like container on an axis (H) perpendicular to said container, said control means (B) being connected, with a first working end, situated inside said box-like container, to actuating means (A), and with a second working end, situated outside the box-like container, to a first cutter knife (C) of said knives, said control means (B) being driven, by said actuating means (A), into alternate oscillation on said axis (H), so as to drive said first knife (C) into reciprocation, the system being characterized in that it includes connection means (E,G) supported by said box-like container and linked to said main control means (B) at said first inner working end and connected to a second cutter knife (D) of said knives, said connection means (E,G) being operated by said main control means (B) so as to drive said second cutter knife (D) into reciprocation in direction opposite with respect to the reciprocation of said first cutter bar (C). System, according to claim 1, characterized in that said connection means (E,G) include at least one drive control guide (E) equipped with a first head sliding in a relative seat (S), which is made in said box -like container, and with a second head, which is fastened, by fastening means (F), to an element (G) connecting to said second cutter knife (D), said drive control guide being operated by said first inner working end of said main control means (B). System, according to claim 1, characterized in that said connection means (E,G) include at least one drive control guide (E) having a first head sliding in a relative seat (S), which is formed by a support placed on said box -like container, and with a second head, which is fastened, by fastening means (F), to an element (G) connecting to said second cutter knife (D), said drive control guide being operated by said first inner working end of said main control means (B). System, according to claim 2 or 3, characterized in that the relative positioning of said first head of the drive control guides (E) with respect to said first working end of said main control means (B) is adjustable by said fastening means (F). System, according to claim 1, characterized in that said main control means (B) include a first type lever and in that said actuating means (A) include an eccentric control shaft. System, according to any of previous claims, characterized in that said first working end of said main control means (B) and said drive control guides (E) work completely immerse in an oil bath. System, according to any of previous claims, characterized in that said second knife (D) is situated under said first knife (C). System, according to any of previous claims, characterized in that said second knife (D) is situated over said first knife (C).

Inventors: LOSI ROBERTO, LOSI, ROBERTO
Applicants: LOSI VITTORIO DI LOSI ROBERTO, LOSI, VITTORIO DI LOSI ROBERTO & C. S.N.C.
Application year: 2001
Main classification: A01D34
IPC codes: A01D34