FR2494787A1 - Cable mounting clamp with tensioned strap - uses semicircular base, with attachment bolt to support cables and lever-tensioned flexible tongue to hold cables in place - Google Patents

Abstract

The cable mounting clamp has a bolt for attachment to a support and a semiconductor lower and to support the cable bundle, with a flexible strap drawn tight over the top of the bundle by a lever mechanism, then clamped in place. The lower part of the mounting clamp is a semicircular metal band (14) with a soft lining material (20) to prevent damage to the cable insulation. A bolt (16) is attached to permit fixing to a support. The cable bundle (12) is laid across the lower half and the flexible strap (18) pulled over the cable bundle then inserted under a lever (22) with a serrated curved edge which is used to rack the strap tight. A lever (28) on top of the tension lever (22) is then forced down to clamp the strap.

Description

Support collar for elongated components such as electrical cables.

 The present invention relates to collars for supporting elongated members such as electric cables and pipes, flexible or not.

 The electrical cables used for the distribution of electrical energy are either laid on a surface or held by support collars spaced along their length. Known support collars comprising two sectors held by screws have drawbacks because they must be adapted to the particular diameter of the cable. A cable fixing device is already known, described in French patent no. 2 395 418, comprising a cradle in which is intended to accommodate a cable and a closure member hooked onto the cradle on one side by a hook. being housed in a notch and on the other side by a toggle type locking device. This known device has numerous advantages but also certain disadvantages.

Thus, each necklace is only suitable for a small number of dimensions. It is made up of several parts so that one of them can be lost. Finally, the installation of the cables requires that they be maintained when the toggle locking device is placed in the closed position. In addition, this device is intended for the support of cylindrical cables and, when it must maintain a set of three cables for example, corresponding to the three phases of a three-phase current, shoes molded in shape must maintain the cables so that they can be tightened by the device.

 The invention relates to a support collar which does not have these drawbacks. More specifically, it relates to a support collar of which all the elements are fixed on each other so that none of them can be lost. This collar allows adjustment whatever the size of the cable or that of a group of several cables, for example three or other, within a wide range of dimensions. No adjustment is necessary beforehand depending on the size of the cable, because the length is automatically adjusted when the collar is locked.

 In addition, the support collar according to the invention avoids any contact between the supported cables and metal parts. It provides cable support in a flexible manner so that it compensates for variations in cable diameter, especially when their dimensions vary due to overheating.

 In addition, the weight and the cost of the collar according to the invention are lower than those of known collars.

 The invention gives all these advantages by using a strap which surrounds part of the cable or cables to be supported and the length of which is continuously adjustable.

 More specifically, the invention relates to a support collar for an elongated member, of the type which comprises a cradle secured to a fixing member, a closure element movable relative to the cradle between an open position in which it allows the passage of the member to be supported between it and the cradle, and a closed position in which the member to be supported is clamped between the cradle and the closing element, and a movable locking device between an unlocked position and a locking position, the collar being intended to be disposed in a plane substantially transverse to the longitudinal axis of the elongate member to be supported according to the invention, the closing element is a strap fixed to the cradle, even when it is in the open position, and the locking device comprises a toggle type tensioning device and a locking device mounted on the tensioning device so that, during operation, the strap is of first fixed on the tensioning device by the locking device, then is tensioned by the tensioning device.

 The toggle tensioning device advantageously comprises a lever articulated on the cradle about an articulation axis which is substantially parallel to the longitudinal axis of the member to be supported but which is located radially more outside than the strap. when the latter is in the closed position and when the locking device is in the locked position.

 The locking device is advantageously a key articulated on the lever around an axis which is substantially parallel to the axis of articulation of the lever on the cradle, this key having a claw which is substantially parallel to the axis of articulation and which approaches the lever when the key is put in its locked position. The key is advantageously mounted on the handle in a direction such that the forces applied by the strap to the claw when the collar is in the closed position, tend to increase the blocking of the key.

 The collar advantageously comprises a plastic foam pad fixed on the face of the cradle rotated on the side of the strap when the latter is in the closed position.

 The strap is fixed to the cradle in any suitable way, for example by rivets.

 The fixing member integral with the cradle is advantageously a threaded rod, for example welded, the rod being disposed on the cradle so that, when it is horizontal and when the collar is in the position of use, it delimits an open cavity practically up.

 The cradle has for example a shape of an arc of a circle or a V. It is however advantageous that the cradle has a substantially flat part on which the lever is mounted.

 The collar further includes a safety device which, when in position, blocks both the handle in the locked position and the key in the locked position.

Other characteristics and advantages of the invention will emerge more clearly from the description which follows, given with reference to the appended drawings in which
- Figure 1 is a perspective, with parts broken away, of a support collar according to the invention, in the closed position on a group of three three-phase power cables;
- Figure 2 is an elevation of a collar similar to that of Figure 1, in the open position
- Figure 3 is an elevation of a collar according to another embodiment of the invention, in the position of cooperation with three electric cables; and
FIG. 4 is an enlarged section of the locking device of a collar according to the invention, very similar to that of FIG. 3.

 FIG. 1 represents a support collar 10 according to the invention, placed around electrical cables 12.

Three insulated cables are shown in Figure 1, but it should be noted that it often happens that these three cables are associated with a fourth which is devoid of insulation and which corresponds to the neutral of a three-phase network. Usually, this fourth cable is advantageously disposed in the space delimited between the three cables 12.

 The collar 10 according to the invention comprises a metal cradle 14, mounted on a rod 16 constituting a device for fixing the collar, for example on a pole.

This rod 16 normally carries a washer, a stirrup, a locking nut, etc., in a well known manner. A strap 18, advantageously formed by weaving "nylon" threads, is riveted to one end of the cradle 14 and it pushes the cables 12 against a pad 20 of plastic foam, for example polyurethane foam, glued to the cradle 14. The strap 18 is held taut by a locking device which comprises a lever 22 articulated on lugs 24 which protrude from the cradle 14, around axes 26. A claw key 28 is articulated on the lever 22 as indicated by the reference 30. This reference advantageously designates holes formed in two flanges of the handle 22 and in which pass pins which project laterally from the key 28.

 The cradle 14 further carries tabs 32 between which are housed the ends of the handle 22 and the key 28, in their closed or locked position. A safety pin, not shown, can then be slid into the holes 34 of the legs 32 and then keeps the handle 22 and the key 28 in their idea lock position.

 The constitution and operation of the locking device which comprises the lever and the key are described in more detail in the remainder of this specification, with reference to FIG. 4.

 The use of the support collar according to the invention is as follows. The collar in the open position as shown in Figure 2 is attached to a suitable device, for example a pole. When this operation has been carried out, the support collar has the position shown in FIG. 2, that is to say that the cradle 14 delimits a cavity open upwards. The cable or cables to be supported are then laid in the cradle, on the pad 20 of foam. Given this arrangement of the cradle, the operator can release the cable since the weight of the latter is supported by the cradle.

 The operator then grasps the free end of the strap 18 and introduces it between the handle 22 and the key 28, and more precisely its claw 36 (FIG. 1), while lifting the handle 22 so that it occupies a position higher than that shown in Figure 2. The operator who slightly tightened the strap 18 so that it does not leave too much play, then locks the key 28 on the handle 22 by bringing these two elements together so well that the claw 36 penetrates firmly into the strap and slightly pushes the latter upwards in FIG. 2. At this time, the operator only has to lower the lever until it occupies the position represented in FIG. 1. In this position, the strap is guided along the end of the cradle, near the legs 24 and it is closer to the cradle than the axes 26 which allow the articulation of the lever 22. Consequently, the tensioning forces of the strap 18 tend to hold the handle 22 against the cradle 14, in accordance with the well known operation of the toggle mechanisms. When lowering the handle 22, the strap 18 is strongly tensioned so that it pushes the cables 12 against the pad 20 of foam. When the strap is tightened, a safety pin can be slid into the holes 34 so that it keeps the handle and the key in their locked position. However, this pin is not essential since the tensioning forces of the strap 18 are not only tend to hold the lever against the cradle but also tend to hold the key 28 against the lever 22, by traction exerted on the claw 36 ..

 The safety device is however advantageous because electric cables such as 12 which transmit currents of high intensity at times and of low intensity at other times, present significant deformations.

It may therefore happen that the strap 18 relaxes as a result of the contraction of the cables 12. Under these conditions, the handle 22 could be released. Furthermore, a very significant swelling of the cables 12, when they occupy not the position indicated in FIG. 1 but that which is represented in FIG. 3, can cause a separation of the strap at the end of the cradle which is close to the tabs 24 and can then move the strap apart from the axes 26. In this case, the handle 22 is no longer blocked and, in the absence of a safety pin in the holes 34, it can open.

 These two extreme cases considered are however very rare and do not correspond to normal conditions of use. It should however be noted that this pin passing through the holes 34 allows almost absolute security, whatever the conditions.

 Note in Figure 1 that the cables 12 are not in contact with any metal part. In fact, they are only in contact with the pad 20 of plastic foam, for example polyurethane, and of the strap 18, for example a textile strap formed of "2Nylon". They therefore do not undergo any deterioration, even when they contract and expand.

 Although it has been indicated that the strap 18 could be formed from woven "Nylon" threads, it can be any suitable strap, stretchy or not. Indeed, we note that the weight of the cables is fully supported by the cradle and its support. The strap 18 only maintains the cables against the cradle.

 It is also noted in FIG. 1 that the maintenance of the cables does not require any additional member, molded to the shape of the cables or of the cradle. In addition, a collar made with a given dimension is suitable for cables of very different dimensions. For example, when the cables are relatively small, they can be arranged as shown in Figure 1, and when they are relatively large, they can be arranged as shown in Figure 3, described later in this specification. The same collar is therefore suitable over a very wide range of dimensions.

 In addition, the length of the strap can be adjusted at will and continuously by simply tightening the key 28. Consequently, the force applied to the cables can have any desired value.

 It has been indicated in FIG. 2 that the strap 18 was held on the cradle 14 by rivets 38. This type of attachment is simple, robust and inexpensive. However, other devices can be used (notches formed in the cradle and buckle in the strap, etc.).

 Although the cradle 14 has been shown with a section in an arc, this shape is not essential. For example, Figure 3 shows an embodiment in which the cradle is not in an arc but has a V shape.

 More specifically, the support collar 40 according to the invention, intended for holding electrical cables 12, comprises a cradle 42 provided with a rod 44. A strap 46 is fixed by rivets 48 to a first end of the cradle and it repels the cables 12 against a pad 50 formed from a plastic foam. The strap 46 passes, at the other end of the cradle, between two legs 52 on which a handle 54 is articulated at the level of axes 56. A key 58 for locking can pivot in holes 60 in the flanges of the handle 54 and is intended to block the strap 46 against the lever 54, in any desired position.

The free ends of the lever and of the key are arranged, in the closed position, between lugs 62 carried by the cradle 42, these lugs having holes 64 intended for the passage of a safety pin. All these elements are similar to those of the embodiment of Figures 1 and 2, but it is noted that the cradle 42 has a shape different from that of the cradle 14. In this case, the cables tend to take the position shown in the figure 3.

 The advantage of the collar 40 of FIG. 3 is that it has a lower cost than that of FIG. 1. In fact, the cradle can be produced inexpensively since the lugs 52 and 62 can be formed in a substantially planar part, that the rod 44 can be welded on a substantially planar part, and that the handle 54 can be formed simply by bending sheet metal, without drawing to the rounded shape of the cradle.

 We now consider in more detail an embodiment of the locking device. The references identical to those in FIG. 3 designate similar elements. Thus, a cradle 42 has a substantially planar portion in which the tabs 52 and 62 are formed, either by cutting and folding, or by welding.

The handle 54 has a substantially flat body 66 formed of sheet metal folded at one end 68 so that it can be easily grasped with the fingers. The body 66 has two flanges 70 laterally, the front ends of which are drilled for the passage of the axes 56. These axes are advantageously in the form of rivets which allow the rotation of the lever 54 on the legs 52.

 The key 58 is simply formed by folding a sheet metal blank of which protrude two pins intended to be housed in the holes 60 of the flanges 70 of the lever 54.

In this way, the handle 54 and the key 58 can be simply formed by folding sheet blanks. Note however that the end of the key 58 which carries the claw 72 is advantageously machined so that the claw bites well in the strap 46 without cutting it.

 The end 68 of the lever and the end 74 of the key are intended to be retained by the safety pin which passes through the holes 64 in the tabs 62, even when the strap is placed between the lever and the key. Thus, when the device must be unlocked, a simple pull on the end of the strap, after removing the safety pin, releases the strap which is no longer tight between the claw and the handle. The strap can then be easily removed and at the same time the handle is released.

 Although a locking device comprising a claw key has been described, it may be any known device, for example of the pin or eccentric type, capable of locking the strap on the lever.

 Although the invention has been described with reference to the support of electric cables, it is understood that it applies to other fields and in particular to the support of pipes. For example, it is particularly suitable for supporting flexible compressed air pipes.

Claims (10)

1. Support collar for an elongated member, of the type which comprises  - a cradle (14) secured to a fixing member (16),  - A closing element (18) movable relative to the cradle between an open position in which it allows the member to be supported to pass between it and the cradle, and a closed position in which said member to be supported is clamped between the cradle and the closure element, and  - a locking device (22, 28) movable between an unlocked position and a locking position,  said collar being intended to be disposed in a plane substantially transverse to the longitudinal axis of said elongated member to be supported,  said collar being characterized in that  the closing element (18) is a strap fixed to the cradle even when it is in the open position, and  the locking device comprises a tensioning device (22) of the toggle type and a locking device (28) mounted on the tensioning device,  - so that, during operation, the strap is first fixed to the tensioning device by the locking device and then is tensioned by the tensioning device. 2. Collar according to claim 1, characterized in that the tensioning device (22) with toggle joint comprises a lever articulated on the cradle around an axis (26) of articulation which is substantially parallel to the longitudinal axis of the 'organ to be supported, this axis being radially more outside than the strap when it is in the closed position and when the locking device is in the locked position. 3. Collar according to claim 2, characterized in that the locking device (28) comprises a key articulated on the lever around an axis substantially parallel to the axis of articulation of the lever (22) on the cradle, the key having a claw (36) which is substantially parallel to the axis of articulation and which approaches the lever when the key is put in the locking position. 4. Collar according to claim 3, characterized in that the key (28) is mounted on the handle in a direction such that the forces applied by the strap on the claw when the locking device is in the closed position, tend to increase the key lock. 5. Collar according to any one of the preceding claims, characterized in that it further comprises a pad (20) of plastic foam fixed on the face of the cradle which is turned towards the strap in the closed position. 6. Necklace according to any one of the preceding claims, characterized in that the strap (18) is fixed to the cradle (14) by rivets (38). 7. Collar according to any one of the preceding claims, characterized in that the fixing member which is integral with the cradle is a rod (16) fixed to the cradle, the latter having a shape such that, when the rod is horizontal and when the collar is in the use position, it delimits an open cavity practically upwards.  8. Necklace according to any one of the preceding claims, characterized in that the cradle has an arc or V shape (10, 40). 9. Collar according to any one of claims 1 to 7, characterized in that the cradle (40) has a flat part on which is mounted the handle (54). 10. Collar according to any one of the preceding claims, characterized in that it further comprises a safety device which, when in position, blocks both the handle (22) in the locked position and the key (28) in the locked position.