Technical Background In the construction, agricultural and gardening fields and the like there are many portable machines that are carried by an operator. The examples of such machines include pneumatic hammers, vibratory wreckers, etc. in the construction field, specialty picker, vibrators, land clearing machines, blowers, chain saws, etc. in the agricultural field, and hedge cutters, lawn mowers, knapsack sprayers, etc. in the gardening field.

The machines of this kind are frequently of the self-driven type, and thus they are actuated by an internal combustion engine being likely to transmit substantial vibrations to the machine frame or holder. Many of these machines, such as for example wreckers, vibrators, <BR> <BR> hedge cutters, etc. , do as well include mechanisms being apt to generate vibration or reciprocating motions between different portions of the machine, these vibrations and/or motions a Iso b eing 1 ikely t o b e transmitted to t he m achine frame o r h older, and from t his latter to the operator being all the time in contact wit the machine. The result is that s aid vibrations and/or motions can in a short time cause a fatigue in the operator which in the long term can bring about a serious health problem.

Vibration absorbing systems are known which are based on resilient elements such as <BR> <BR> spring members, springs, rubber members, hydropneumatic devices, etc. , and/or elastomer blocks. Their main problem is that when they absorb a motion component acting in one direction they at the same time accumulate the energy having been detracted from the system to thereupon release it thereby causing a rebound effect. The elements being made of rubber or another elastomer have besides the drawback that they are only apt to admit movements within a relatively short travel.

Other vibration and motion absorbing elements or devices are based on the principle of the articulated parallelogram to absorb movements within fairly long travels. The drawback resides nevertheless in this case in the fact that the opposite sides of the parallelogram are

submitted to motions bringing them closer together or farther apart from each other on top of the shifting motions.

Patent EP-A-0566436 discloses a device being apt to fixedly secure a load on a support and comprising at least a body being shaped as a band having a width being significantly bigger than its thickness, with two opposite, elongated lengths facing each other, said lengths being at a first end connected to each other through a curved link. The second ends of the elongated lengths make up fastening members being apt to be connected to the load and the support, respectively. Said body is made up of several spring steel layers being sandwiched in elastomer layers and admits relative motions between the load and the support with at least two-dimensional components through resilient deformation. The above- mentioned problem of the accumulation of resilient energy and the consequent rebound effect are nevertheless still persisting due to the resilient nature of the body's material.

An object of the present invention is to provide a motion two-or three-dimensional component absorbing and isolating, connecting element being applicable to machines and mechanical devices and implements where said connecting element admits relative two-or three-dimensional motions within relatively long travels between a first and second portions of the machine or mechanical device or implement without accumulating resilient energy in significant amounts.

Another object of the present invention is to provide a motion two-or three- dimensional component absorbing and isolating, connecting element being applicable to machines and mechanical devices and implements where said connecting element is apt to be produced in an easy and quick way and at a low cost.

Summary of the Invention According to the present invention the above and other objects are attained by providing a motion two-or three-dimensional component absorbing and isolating, connecting element being applicable to machines and mechanical devices and implements. The element is made up by at least a first body having an annular, elongated configuration and being shaped as a band having a width being significantly bigger than its thickness, said band being made of a resilient, tension resistant material and comprising two opposite, elongated lengths facing each other, said lengths being connected through curved end links, and first and second fastening members connecting said elongated lengths to respective first and second portions of a machine or mechanical device or implement being likely to effect relative motions having at least two-dimensional components. When facing said relative motions said first body operates by means of at least longitudinal shifting motions in opposite directions of the elongated lengths and of the first and second fastening members being attached to them and by means of motions of the elongated lengths which bring them closer together or farther apart from each other.

During the above-mentioned longitudinal shifting motions in opposite directions of the elongated lengths and by virtue of the resilient nature of the material of the bodies each of the elongated lengths progressively adopts the configuration of one of the curved links at an end whereas at the other end it is the curved link that progressively adopts the configuration of the elongated length, thereby acting much like a"track" type crawler tread. This behaviour admits fairly long motion travels in the longitudinal direction of the elongated body, and it does besides admit movements in a"compression/tension"direction, i. e. the above-mentioned motions that bring the elongated lengths closer together or farther apart from each other. It will be understood that both"caterpillar"effect and"compression/traction"movements can be made simultaneously and in a combined manner, whereby the connection member permits relative movements in any of the directions included in a plane, in other words, relative movements with at least two-dimensional components. A certain flexibility of the first body in a transverse direction to said plane allows certain movement components in said transverse direction, whereby the member described up to now is applicable in those cases in which there are one or two main directions of vibration and/or movement.

When it is desired to absorb three-dimensional movements, the connection of said second attachment member to said second part of the machine, device or mechanical implement is made advantageously by means of a second body having generally an annular elongated shape similar to the first body described above, in other words, in the form a band with two opposed elongated sections, facing each other, linked by curved end sectors. The second attachment member is connected to one of said elongated sections of the second body and a third attachment member connects the other of the elongated sections of the second body to said second part of the machine, device or mechanical implement. Said second body is arranged forming an angle with respect to the first body, with the first and second parts being susceptible of relative movements with three-dimensional components. By means of this arrangement, the group of members works with regard to said relative movements by means of longitudinal movements, in opposed directions, of the respective elongated sections of the first and second bodies, and by means of approximation/distancing movements of the respective elongated sections.

Although in some applications it can be advantageous for said angle between the first and second bodies to be an acute angle, generally a right angle is preferred in order to have movement absorption members in the three directions of the three-dimensional space.

Generally, the relative movements between the first and second parts of the machine are alternative, of the vibrationary or reciprocal type, with strokes within a determined length range and they can adapt the annular elongated bodies of the member of the invention to said

stroke length range upon selecting the length of the band and the features of material. Thus, the member of this invention virtually eliminates the transmission of alternative three- dimensional linear movements as well as vibrations in all the magnitudes and frequencies thereof between first and second parts of a machine, device or mechanical implement.

Moreover, it significantly reduces the dangerous ricochet effect that exists in the prior art systems based on rubber, springs and other resilient elements, where the cycles of alternative linear two-or three-dimensional movements creates an alternating positive-negative elastic energy that limits the attenuation of the alternative linear movements or vibrations generated by a mobile or active part with respect to the other part which it is desired to isolate.

Said flexible and tensile resistant material of the first and second bodies has, also, a low flexing fatigue coefficient, and it is selected together with the dimensions of the bodies in order to provide a predetermined resistance to the flattening in said curved end sectors. A suitable material is, for example, any material intended for tension belts or conveyor belts, and it can have one single layer or several layers, with or without internal reinforcement. Said resistance to the flattening of the curved sectors allows the member to withstand a certain pressure on its elongated sectors without preventing its referenced"caterpillar effect".

However, in many applications, one of the first or second parts of the machine has a shape enveloping the other and the members or groups of members of the invention are arranged so that they connect both first and second parts so that a movement, for example, caused by compression on one of the members of groups of members is compensated by a pulling movement in another or other members or groups of members. Thus, one of the first of second parts of the machine remains suspended or"floating"within the enveloping shape of the other part, as described in greater detail below.

An easy and economical way to produce the first and second bodies is from a piece of band or belt, that is easily obtainable, having a selected length joined by its ends so that it forms a closed loop. Another way of producing the first and second bodies is by shaping them like a continuous band or belt forming a closed loop, with the precaution that said continuous band, in the absence of external forces, has a circular shape and adopts the required annular elongated shape by compressing two of its opposed sides.

Brief description of the drawings The above features and advantages and others shall be more comprehensible from the detailed description of some embodiments with reference to the attached drawings, in which: Fig. 1 is a diagrammatic side elevation view of the joining member according to this invention, in accordance with a basic embodiment example thereof ;

Fig. 2 is a diagrammatic side elevation view of the joining member of Fig. 1 in two opposed positions of"caterpillar"type movements; Fig. 3 is a diagrammatic side elevation view of the joining member of Fig. 1 in two positions of"compression/pulling"type movement; Fig. 4 is a diagrammatic plan view showing a piece of band or belt from which the annular elongated body of the member in Fig. 1 can be made; Fig. 5 is a diagrammatic perspective view showing the annular elongated body made from the piece of band or belt illustrated in Fig. 4; Fig. 6 is a partially sectioned diagrammatic side elevation view of the joining member produced from the piece of band or belt illustrated in Fig. 4; Fig. 7 is a diagrammatic perspective view showing a continuous band or belt forming a closed loop, which has a circular shape in absence of external forces, from which the annular elongated body of the member in Fig. 1 can also be made; Fig. 8 is a diagrammatic perspective view showing a joining member according to this invention in accordance with a more complex embodiment example; Fig. 9 is a diagrammatic perspective view showing a variant of the joining member in Fig. 8 ; Fig. 10 is a perspective view showing an agricultural machine incorporating various joining members according to this invention between parts of said machine provided with relative movement ; Fig. 11 is an enlarged detail of the view in Fig. 10 showing the connection of a handle to said machine by means of joining members according to this invention; Fig. 12 is another enlarged details of the view in Fig. 10 showing the connection of another handle as well as the connection of a body support to said machine by means of joining members according to this invention; Fig. 13 is an enlarged perspective view showing a variant of the connection of the handle in Fig. 11 to the machine; and Fig. 14 is an enlarged perspective view showing a variant of the connection of the handle in Fig. 12 to the machine.

Detailed description of some embodiments With reference first of all to Fig. 1, a joining member is shown generally designated by reference number 1, designed to join first and second parts 41,42 of a machine, device or mechanical implement, susceptible of undergoing relative movements with at least two- dimensional components, and to absorb, at least to a significant extent, said movement components, which are at least two-dimensional. Member 1 is made up of at least one body

10, having an annular elongated shape, in the form of a band the width of which is significantly greater than the thickness thereof (better view in Figs. 5 and 7), made from flexible, tensile resistant material. Said body 10 comprises two opposed, elongated sections 12, facing each other, linked by means of curved end sectors 13, and first and second attachment members 31,32 that connect said elongated sections 12 respectively to said first and second parts 41,42 of the said machine, device or mechanical implement. In the interest of greater clarity in the drawings, elongated sections 12 have been shown in straight lines although, by virtue of the flexibility of the material from which body 10 is made, they can adopt a variety of forms always linked by said curved end sectors 13.

Figs. 2 and 3 show how body 10 operates with regard to said relative movements between first and second parts 41,42. Thus, Fig. 2 shows that first part 41 remains stationary while second part 42 performs a reciprocal movement with respect to first part 41 in a longitudinal direction in relation to the annular elongated shape of body 10, indicated both ways by means of the arrows D1. With regard to said movement, and by virtue of the flexible and tensile resistant material from which it is made, body 10 is deformed by longitudinal movements, in opposed directions, of elongated sections 12 together with first and second attachment members 31,32 joined thereto. Fig. 2 shows in solid lines a first end position of the reciprocal movement of second part 42 and in dotted lines a second end position of the reciprocal movement of second part 42. During such movements, each elongated section 12 gradually adopts at one of its ends the shape of one of the curved sectors 13 while each curved sector 13 adopts at the other end the shape of one of the elongated sections. As a result, said annular elongated shape is maintained as it moves sideways according to the longitudinal components D1 of the movement of second part 42 transmitted by the second attachment member 32. This behaviour is similar to that of a"caterpillar"type tread.

Fig. 3 shows that first part 41 remains stationary while second part 42 carries out a reciprocal movement with respect to first part 41 in a transverse direction in relation to the annular elongated shape of body 1, indicated both ways by the arrows D2. With regard to this movement, and by virtue of the flexibility and tensile resistance of the material from which it is made, body 10 is deformed by transverse movements, in opposed directions, of elongated sections 12, whereby elongated sections 12 together with first and second attachment members 31,32 joined thereto are moved closer or further away. Fig. 2 shows in solid lines a first position of the reciprocal movement of second part 42 and in dotted lines a second position of the reciprocal movement of second part 42. During such movements, each elongated section 12 moves closes to or further away from the other while curved segments 13 adopt a smaller or greater radius. As a result, said annular elongated shape widens or narrows according to the transverse components in direction D2 of the movement of second part 42 transmitted by second attachment element member 32. Both components in the

longitudinal and transverse directions D1, D2 can be made simultaneously without interfering with the movements to deform or adapt body 10 and without substantially accumulating elastic energy.

When a certain elastic resistance is desired upon bringing elongated sections 12 closer together in direction D2, said flexible and tensile resistant material of the first body 10 is selected together with the dimensions thereof in order to provide a predetermined resistance to the flattening of said curved end sectors 13.

Figs. 4 and 6 illustrate an easy and economical way to produce body 10. Fig. 4 shows a piece of band or belt 1 la from which body 10 is made. The piece of band or belt 1 la has a selected length, a width significantly greater than its thickness and it terminates in two straight end edges 2a, 2b. In a central part of the piece of band or belt 1 la there is an orifice 3 and a semi-orifice 4a, 4b is made in each of said straight end edges 2a, 2b. Fig. 5 shows the piece of band or belt 11 la with its straight end edges 2a, 2b butted together forming an annular, elongated, closed loop body. Opposed semi-orifices 4a, 4b form an orifice 4 in an elongated section 12 opposed to the other elongated section 12 in which there is said orifice 3 initially situated in the centre of the piece of band or belt l la. Finally, Fig. 6 shows through screws 5 for orifices 3 and 4, screwed into the respective first and second parts 41, 42. A washer 6 pressed against straight end edges 2a, 2b ensures that said edges remain in a butt arrangement and fixed to second part 42. The flexible, tensile resistant material, and a low flexing fatigue coefficient, useful for preparing the piece of band or belt 1 Ia is easily obtainable at a relatively low cost as the material for the flat transmission belt or conveyor belt, and the operations necessary for forming body 10 therefrom are simple and require a minimum number of tools and equipment.

Fig. 7 shows another possible way of forming body 10, which here is made up of a continuous band or belt 1 lb forming a closed loop, and provided with a pair of holes 7a, 7b in approximately equidistant areas along the perimeter thereof. By means of said holes 7a, 7b an assembly is obtained (not shown) with screws similar to that shown in Fig. 6. It is important that said continuous band or belt llb has, in the absence of strong external forces applied to first body 10, a circular shape from which, by means of a slight pressure, the required annular, elongated shape is obtained. This is such so as to avoid the presence of elastic forces in the curved sectors which could occur in the event that the band or belt were shaped directly as an annular, elongated body. Moreover, the circular shaped band or belt lib can be obtained by slicing a tubular body of suitable material.

Fig. 8 shows a joining member la in accordance with this invention, according to a more complex embodiment example, which is capable of absorbing three-dimensional relative movement components between the first and second parts 41,42. Said member la comprises a first body 10 similar to that described in relation to Figs. 1 to 3, with first and

second attachment members 31,32. However, here, while first attachment member 31 joins one of the elongated sections 12 of first body 10 directly to first part 41 (not shown in Figs. 8 and 9 in the interest of greater clarity in the drawing), a second body 20 is interposed between second attachment member 32 and said second part 42 (not shown in Figs. 8 and 9). Said second body 20 is similar to first body 10, and has a generally annular, elongated shape, in the form of a band 21 with two opposed elongated sections 22, facing each other, linked by curved end sectors 23. Second attachment member 32 joins the corresponding elongated section 12 of first body 10 to one of said elongated sections 22 of second body 20 and a third attachment member 33 joins the other of the elongated sections 22 of second body 20 to said second part 42. Second body 20 is arranged forming a right angle with respect to first body 10, so that first and second parts 42 are susceptible of relative movements with three- dimensional components. Thus, first body 10 operates as described above to absorb movement components in direction D1, second body 20 operates in a similar manner to absorb movement components in a direction D3 normal to direction D2, and both first and second bodies 10,20 engage to absorb movement components in direction D2 normal to directions D1 and D3, by means of respective elongated sections 12,22 moving closer and further away.

Fig. 9 shows a member or group of members lb similar to the member or group of members la in Fig. 8, but in which the angle forming second body 20 in relation to first body 10 is an acute angle, which can be advantageous for certain applications.

Fig. 10 shows a portable agricultural machine of a well-known type, generally designated by means of reference number 40. Machine 40 comprises a tubular support 60 in the inside of which there is a transmission shaft connecting a motor 61, joined to one end of tubular support 60, to a vibration generating mechanism 62 joined to the other end. Said vibration generating mechanism 62 is connected to a hook 63 adapted to hold the branch of a tree and to transmit a vibrationary movement to said branch in order to shake the fruit of it.

Machine 40 is designed to be carried on the shoulder of an operator using a harness for this purpose (not shown). In the example shown in Fig. 10, machine 41 rests against the operator's right hip by means of a body support 64. The operator manipulates the machine 40 by means of a right-side handle 65, which includes several control organs, and a left-side handle 66. For the purpose of this specification, tube 60 of machine 40 represents the first part 41 referenced in Figs. 1 to 9, while body support 64 and handles 65,66 represent, each separately, the afore- mentioned second part 42. Here, first part 41 is an active part, subjected to vibration or alternative movement, and second part 42 is a passive part which it is desirable to isolate from said vibration or alternative movement.

Moving on to Fig. 12, it shows an enlarged view of the connection of body support 64 and handle 65 to tubular support 60 of machine 40 by means of members or groups of

members 1, la according to this invention. Although the possibility is contemplated of forming a connection in which an area of first part 41 of machine, device or mechanical implement 40 is connected by a single member or group of members (not shown) to a respectively opposed area of second part 42 of machine 40, it is preferred that at least two areas of first part 41 of machine 40 are connected by respective members or groups of members 1, la, lb to at least two respectively opposed areas of second part 42 of machine, device or mechanical implement 40.

The connection of body support 64 (or second part 42) to tubular support 60 (or first part 41) constitutes an example in which said two areas of second part 42 are on the same side and two respective members 1 substantially parallel to one another connect the two areas of the second part with the corresponding two areas of the first part. It will have been noticed that members 1 are of the simple type described above in relation to Figs. 1 to 3, each of which is made up of a body 10 and first and second attachment members 31,32, although equally the same assembly could be obtained with members la, lb of the complex type described above in relation to Figs. 8 and 9. In any event, owing to the fact that there is no stop piece for the approximation of body support 64 (or second part 42) to tubular support 60 (or first part 41), in this assembly it is advantageous that the material for the annular bodies be selected in order to provide a predetermined resistance to the flattening of the curved end sectors of the annular bodies in order to limit said approximation by means of a relatively elastic stop piece.

To the contrary, and continuing with Fig. 12, the connection of right-side handle 65 (or second part 42) to tubular support 60 (or first part 41) constitutes an example in which said two areas of second part 42 are arranged on opposite sides of first part 41, and where said members or group of members 10,20 ; 31,32, 33 are substantially aligned. For this reason, in the illustrated example, the two areas of first part 41 are formed by a pair of arms 43,44 attached to tubular support 60 so that they define a rigid frame inside which handle 65 is mounted by means of members la of the complex type described in Fig. 8, in other words, with first and second bodies 10,20 and first, second and third attachment members 31,32, 33, although equally it could be installed with members 1 of the simple type described in Figs. 1 to 3. Since the distance between said arms 43,44 is fixed, and members la are aligned, the approximation/distancing movements of the elongated sections of members la situated on opposite sides of the handle are mutually compensated.

Returning to Fig. 11, the connection of left-side handle 66 (or second part 42) to tubular support 60 (or first part 41) constitutes an example in which three areas of first part 41 are connected by respective members or groups of members 1 to three respectively opposed areas of second part 42, and where said second part 42 has an enveloping shape with respect to first part 41 and said three areas are arranged at substantially regular angular intervals with

respect to a centre of said enveloping form, leaving said members 1 inclined in substantially convergent directions. Bodies 10 of members 1 are facing the longitudinal direction of tubular support 60 of machine 40 since this is the main direction of the vibrationary movement generated by vibration generating mechanism 62, although equally they could face in other directions.

Moving now to Fig. 13, it shows a variant of the connection between left-side handle 66 and tubular support 60 (not shown in Fig. 13). Here, the connection is made by means of members la of the complex type described in relation to Fig. 8, each of which comprises first and second bodies 10,20 and first, second and third attachment members 31,32, 33. Handle 66 defines an arc around a base 67, which is provided with attachment means for connecting it to tubular support 60. Said attachment means comprise, for example, an orifice arranged to snugly receive tubular support 60, and a slot 68 extending from the outer part of base 67 to the orifice, a tightening screw being provided to narrow the orifice by reducing the width of the slot. Members la connect the three areas of handle 66 with three areas of base 67 and they are distributed at 120"angular intervals and inclined in substantially convergent directions towards the centre of the orifice in base 67.

Finally, Fig. 14 shows a variant of the connection of right-side handle 65 (or second part 42) to tubular support 60 (or first part 41) of machine 40. In this example, second part 42 has a first end 42a and a second end 42b. On opposite sides of first end 42a there are two of said connection areas and on opposite sides of second end 42b, there are another two of the connection areas. Two connection areas of first part 41 are formed by a pair of appendices 45a. , 45b of a first arm 45 attached to tubular support 60 and another two connection areas of first part 41 are formed by a pair of appendices 46a, 46b of a second arm 46 attached to tubular support 60, so that they define a rigid frame inside which handle 65 is mounted by means of members 1 of the simple type described in Figs. 1 to 3, in other words, with first body 10, and first and second attachment members 31,32, although equally it could be installed with members la, lb of the complex type described in Figs. 8 and 9. Contrary to the assembly example described in relation to Fig. 14, here two members 1 are substantially aligned on opposite sides of said first end 42a and another two members 1 are substantially aligned on opposite sides of said second end 42b, while the two members 1 of first end 42a are substantially parallel to the two members I of second end 42b.

An assembly of electric and/or mechanical transmission cables are sheathed in a flexible hose 47 connected to first end 42a of handle 65 (or second part 42) in order to electrically and/or mechanically connect the control organs in handle 65 to motor 61 and other associated devices. The flexible conduit of the cables and hose 47 allow relative movement between handle 65 and tubular support 60 without damaging them.

A person skilled in the art will be able to introduce numerous modifications, variations and combinations without leaving the scope of the invention as defined in the attached claims.