Stroke damping and method for making said damping

Abstract: The invention relates to a device comprising a frame with a movable member (3) and a fixed member (2), wherein a stop (6) therebetween defines an end position of the movable member. At least one of these members is a tubular member which is provided in the portion co-acting with the stop with a bore (9) facing toward the other member in at least one wall, in which bore (9) is received an elongate element (8) of flexible material clamped fixedly by deforming of the adjoining material of the tube wall. The invention further relates to a method of manufacturing a tubular member provided with a stroke damping, comprising of arranging at least one bore (9) in the wall of the tubular member, placing an elongate element (8) of flexible material in the bore (9) such that a portion thereof protrudes outside thereof, and deforming in a direction towards each other wall portions (10) of the tubular member located adjacently of the bore (9).

Description: The invention relates to a device with a movable tubular member which can be moved into an end position against a stop. Such a device is for instance a feeding fence for cattle, known from the brochure "Spinder Stalinrichting, Leveringsprogramma 1990/1991", wherein the tubular member is a pivoting catching bar. When a tubular member moves against a stop at a certain speed quite a loud, irritating noise occurs. It is therefore known to arrange at the position of the stop a rubber cap or the like which damps the noise. Existing solutions have the drawback that they come loose after a period of time. The invention now has for its object to provide such a device with a stop damping which can function reliably and for a long period of time. According to the invention this is achieved with the device characterized in claim 1. When the adjoining material of the tube wall is deformed the elongate element of flexible material is elastically deformed at the same time, whereby after the deforming operation the passage defined by the bore is narrowed and the elongate element is fixed unreleasably in the tubular member. The protruding portion herein forms the part of the stop which provides the damping of the impact. The invention is particularly suitable for use as a self-catching feeding fence, wherein the tubular member provided with the element of flexible material is a pivoting catching bar. Under the heavy loads to which such feeding fences are exposed the stop damping continues to act reliably during the whole useful life of the feeding fence. A favourable embodiment is herein characterized in claim 3. In such a feeding fence, wherein the top end of the swivel bar has already been flattened anyway in order that it can fit into the channel of the upper profile, only the additional operations of arranging the bore and inserting the elongate element thus have to be carried out. The invention also relates to and provides a method for manufacturing a tubular member provided with a stroke damping. This method is characterized in claim 4. The deforming can be effected here in suitable manner with a pressing operation. A very favourable embodiment is characterized in claim 5. Due to a surface treatment such as thermal galvanizing considerable dimensional tolerances occur irreversibly in the bores present. With the method according to the invention an elongate element of flexible material can still be arranged firmly in the tubular member in a reliable manner even with these considerable dimensional tolerances. It is thus not necessary to only arrange the bore after the galvanizing treatment has been carried out. This latter would of course result in a reduction of the corrosion resistance. A further development is characterized in claim 6. By causing the elongate element to protrude on both sides not only is a very robust fixing of this element achieved but a stop is also obtained which acts on two sides. In preference the elongate element is cut from a length of rubber-like profile material. The cost hereof is very low so that the advantages of the invention can be gained at very low cost. The invention will be further elucidated in the following description with reference to the annexed figures. Figure 1 shows in perspective view a device according to the invention embodied as a self-catching feeding fence. Figure 2 shows a view corresponding with figure 1 of another embodiment. Figure 3 shows a detail along arrow III in figure 1. Figure 4 shows a detail along arrow IV in figure 2. Figure 5 is a view corresponding with figures 3 and 4 of an alternative embodiment. Shown in figure 1 is a feeding fence 1 embodied as a device according to the invention. This feeding fence 1 comprises in known manner a number of feeding locations in which a catching bar 3 is pivotally mounted to a fixed bar 2 at the position of a hinge 4. The catching bar 3 can stand in the shown open position and in an upright closed position. In the upright closed position the catching bar can be held fixedly by locking means (not further shown). At its top end the catching bar 3 is received in an elongate channel-like opening in the underside of the upper profile 5. In the shown open position the bar 3 lies with a stop 7 against the fixed bar 2. In the upright closed position the catching bar 3 lies with a stop 6 against the fixed bar 2. As shown in more detail in figure 3, a bore 9 is arranged in the tubular catching bar 3 at the position of this stop 6, in which bore is inserted an elongate element 8. This latter is of flexible material, such as for instance rubber-like material. In suitable manner the elongate element 8 is a piece cut from a length of rubber-like profile material. This profile material is commercially available for various applications. After the elongate element 8 has been inserted into the opening 9 the portion of the wall of tube 3 adjoining this opening 9 is deformed, in particular the opposite wall portions 10 are pinched together. This operation can take place in a manner that is further self-evident, for instance with a press. Due to this deforming the wall portions 10 are pressed into the passage defined by the bore 9, wherein the elongate element 8 is deformed elastically. This deforming results in a great reaction force, and thereby a great friction force, such that the elongate element is received unreleasably in the tubular member 3. The feeding fence 12 shown in figure 2 likewise has a catching bar 13 pivotally arranged on a fixed bar 15. This catching bar 13 is provided on its top end with a double-sided stop 14 which is shown in more detail in figure 4. Arranged in tube 13 are two oppositely located bores 19 and 20 in which is received an elongate element 18 of flexible material. The end of tube 13 is then flattened so that the wall portions 21 thereof are moved toward each other, wherein the elongate element 18 is clamped fixedly in the above described manner. The flattened top end of catching bar 13 is received in the feeding fence 12 in guided manner in an elongate channel in the underside of the upper profile. Such a construction is per se known. In the case of the feeding fence 12 the catching bar 13, after the bores 19 and 20 are arranged therein, is first galvanized in the usual manner. Protection of the basic material is hereby also ensured at the position of the bores 19 and 20. After galvanizing the elongate element 18 is arranged and the tube end is flattened in the already known manner. The protection obtained by the galvanizing herein remains intact. As shown clearly in figure 4, the elongate element 18 protrudes on either side and thus forms a stroke damping on both sides. As can be seen in figure 2, the one side coacts with the fixed bar 15 and the other side with a projection 16 arranged on the upper profile of the fence 12. The diameter of the bores 19 and 20 can be made so large that, even with the maximum diameter decrease that can be expected as a result of galvanizing, the elongate element 18 can still be pushed through the bores without problem. The diameter of these bores is not critical for a good fixing of the elongate element 18. Figure 5 shows another alternative embodiment. The stop 24 shown therein is arranged in a tubular member at an intermediate position. Here also two oppositely located bores 26 and 27 are arranged through which the elongate element 25 of flexible material is pushed. Thereafter the wall portions 28 of the tube adjoining bores 26 and 27 are flattened, whereby the elongate element 25 is fixed unreleasably in the tube. Although the invention is elucidated on the basis of an embodiment as feeding fence for cattle, countless other applications are possible. Nor is the invention limited to use with tubes with the round diameter shown. Square or otherwise formed tubes can also be used in the invention. The shape of the elongate element is of course also not limited to that shown. It is favourable from a cost viewpoint to make use of elongate elements cut from a length of rubber-like profile material. However, specially formed elongate elements having for instance a wider head could also be applied. Since, as noted above, the diameter of the bores into which the elongate element is inserted is not critical, elongate elements having a cross section other than a circular one can also be used. All these embodiments that are not shown are deemed as falling within the scope of the annexed claims.

Claims: Device comprising a frame with a movable member (3) and a fixed member (2), said movable member (3) being movable on the frame with respect to the fixed member (2), wherein a stop (7) therebetween defines an end position of the movable member (3) with respect to and against the fixed member (2), and at least one of these members is a tubular member (3) comprising an element (8) of flexible material co-acting with the stop (7), said tubular member (3) having at least one tube wall (10) and being provided in the portion co-acting with the stop (7) with a bore (9) facing toward the other member in a tube wall (10), said element (8) of flexible material being an elongate element (8) and being received in said bore (9) and the portion of the tubular member (3) co-acting with the stop (7) being deformed such that the elongate element (8) is clamped fixedly between the tube wall portions adjoining the bore (9). Device as claimed in claim 1, being a self-catching feeding fence (1), wherein the tubular member (3) provided with the elongate element (8) of flexible material is a pivoting catching bar (3). Device as claimed in claim 2, wherein the pivoting catching bar (13) is provided with a flattened top end which is enclosed at the sides in a longitudinal channel of an upper profile of the feeding fence (1), and the elongate element (18) of flexible material is received in the flattened end. Method of providing a tubular member (3) having at least one tube wall (10) with stroke damping, suitable to be used in the device of claim 1, by arranging at least one bore (9) in a wall of the tubular member (3), placing an elongate element (8) of flexible material in the bore (9) such that a portion thereof protrudes therefrom and deforming in a direction towards each other wall portions (19) of the tubular member (3) co-acting with the stop (7) located adjacently of the bore (9) such that the elongate element (8) is clamped fixedly between said tube wall portions (19) adjoining the bore (9). Method as claimed in claim 4, wherein the tubular member (3) is galvanized after arranging of the bore (9) and prior to deforming. Method as claimed in claim 4 or 5, wherein a continuous bore (19, 20) is arranged through opposite wall portions of the tubular member (13) and the elongate element (18) is pushed through both bores (19, 20) protruding on both sides. Method as claimed in any of the claims 4-6, wherein the elongate element (18) is cut from a length of rubber-like profile material.

Inventors: VRIESWIJK ANDRIES, VRIESWIJK, ANDRIES
Applicants: BOER STALINRICHTINGEN, DE BOER STALINRICHTINGEN B.V.
Application year: 1993
Main classification: A01K1
IPC codes: A01K1