TECHNICAL FIELD

The present invention relates to a clamping arrangement; more particularly, it relates to a clamping arrangement that is adapted to a cavity--specifically a cavity formed in a con¬ crete base--and is intended to be able to coact firmly with several wall partitions or wall sections that belong to the cavity.

The clamping arrangement consists of a bolt or pin with asso¬ ciated screw thread; at least one nut in coaction with the screw thread; a washer or other means for which to provide a counter pressure surface that encloses the bolt or pin; and a yoke, that encloses the bolt or pin and is fitted between the washer and the nut.

The yoke and the cavity are further adapted to one another so that the yoke can be brought into a clamping coaction with said wall partitions as the nut is rotated around the bolt or vice versa.

DESCRIPTION OF THE BACKGROUND ART

Regarding clamping arrangements of the kind described above, a previously known arrangement forms a cavity in a concrete base, or a similar base, whose diameter exceeds the diameter of the bolt by a factor of at most two or three.

„ ,,,_ PCT/SE95/01331 6/15334 - 2 -

Such clamping arrangements are adapted to a firm but easily removable coaction with several wall partitions that belong to the cavity, whose arrangements usually consist of two end parts and a means for guiding the end parts to and from one another, where one or several parts, positioned between the end parts, are brought to twist to or from a coaction with said wall partitions by the displacement of the end parts.

Another previously known arrangement shows a spacer between an intermediate part and an end part, which has been adapted to transfer the movement of the end parts to or from one another into a twisting movement of the intermediate part.

As an example of prior art regarding these matters, referen- ces are made to the content of the publication SE 465 633 (Swedish patent application number 86 03509-4).

Further references are made to prior art known through the patent publications DE-A1-2 848 336, DE-A1-2 826 209 and DE-A1-2 849 944.

Regarding a specific application of the present invention, the arrangement is also known to form a relatively large cavity in such things as a concrete base whose diameter is four to five times greater than the diameter of the bolt. A bolt with a washer whose diameter essentially corresponds to the diameter of the cavity is inserted into the cavity, after which the remaining cavity is filled with concrete thereby firmly anchoring the bolt and washer in the concrete base.

The latter embodiment requires that the filled concrete be burnt before the bolt can bear a load. Besides this, the wall structure of the cavity is usually smooth so the filled con¬ crete does not bind well to its surface, wherefore the force that can be permitted to load such an anchorage in the longi¬ tudinal direction of the cavity is limited.

SUMMARY OF THE INVENTION

TECHNICAL PROBLEMS

Taking the background art into consideration, as described above, it ought to be a technical problem to be able to pro¬ vide a means for attaching a clamping arrangement at the specific application where the arrangement will be so firmly related to the cavity that the bolt can be* used and bear a load without the help of a concrete mass.

There is also a technical problem in being able to create a clamping arrangement that can be given ^" a suitable application for either of the previously-described technical applications.

There is also a technical problem in being able to construct, with a clamping arrangement, a yoke that can be used in such a way that it will present a partition in the shape of a collar, which is oriented around and adjacent to the bolt, and a wall structure, which diverges from said collar-shaped partition.

There is also a technical problem in being able to realize the importance of giving said collar-shaped partition a diameter that corresponds, or essentially corresponds, to half the diameter of the cavity.

Another technical problem is to be able to realize the advan- tages and suitability of forming said wall structure and said collar-shaped partition as a single integrated unit, prefer¬ ably in a steel material.

Another technical problem is to be able to realize the impor- tance of the wall structure, being in a non-coacting position relative to the wall partitions, but oriented in an angle that exceeds 45' relative to the centre line of the bolt; for

example, approximately 60 .

Another technical problem is being able to realize the impor tance of forming said wall structure as a conoidal frustum, or as a number of wings—for example, two, three, or four wings--and to relate the wings diametrically to one another, particularly if the number of wings is two or four.

When the wall structure forms wings, it is ^* also a technical problem to be able to realize the importance of equipping th washer with slots, thereby adapting it to coact with and guide the outer parts of the wings in a movement towards the adjacent wall partitions of the cavity.

It is also a technical problem to be able to realize the importance of selecting a thickness for the collar-shaped partition that exceeds the selected thickness of the wall structure.

It is also a technical problem to be able to realize the importance of forming the diverging wings into plane wings.

Yet another technical problem is in realizing the importance of arranging a yoke at each side of the washer and allowing the yokes to act towards one another each time the bolt is rotated.

Another technical problem is to be able to ..realize the impor tance of arranging a first nut to the pin, in order to pro- vide a counter pressure surface; and a second nut that serve as a supporting organ, in order to press, towards the adja¬ cent wall partitions, the edge partitions of the yoke that relates to the outer wall structure, by plastically deformin the edge partitions of the yoke.

Still another technical problem is to be able to realize the importance of arranging the wall structure so that it coacts

with the collar-shaped partition adjacent to a centrally- formed hole in said partition.

Another technical problem is to give said cavity a centred bottom recess into which the inner end of the bolt can be guided and brought to coact with.

SOLUTION

In order to solve one or more of the above-stated technical problems, the present invention is based on a clamping arran¬ gement for a cavity, intended to be able to firmly coact with several wall partitions that belong to the cavity, consisting of a bolt or pin with associated screw thread; at least one nut in coaction with the screw thread; a washer, or a counter pressure surface that encloses the bolt; and a yoke that en¬ closes the bolt and is fitted between the washer and the nut, whereby the yoke and the cavity are adapted to one another so that the yoke can be brought into a clamping coaction with said wall partitions as the nut is rotated around the bolt or pin or vice versa.

With such a clamping arrangement, the present invention shows that said yoke is meant to present a partition in the shape of a collar, which is oriented around and adjacent to the bolt, and a wall structure, which diverges from said collar- shaped partition.

As proposed embodiments, within the scope of the inventive thought, it is shown that the collar-shaped partition is to be given a diameter that corresponds, or essentially corre¬ sponds, to half the diameter of the cavity.

Further, it is shown that said wall structure and said collar-shaped partition form a single integrated unit.

In addition, it is shown that, in a non-coacting position,

the wall structure is oriented relative to the wall parti¬ tions, at an angle that exceeds 45' —preferably approximately 60 ^" —relative to the centre line of the bolt.

It is specifically shown that said wall structure is formed as a conoidal frustum.

In addition, this arrangement shows said wall structure forming wings, preferably diametrically opposed wings. The wings may also be plane.

Given an embodiment whose wall structure forms wings _t it is suggested that the washer or the counter pressure surface be equipped with slots that are adapted to coact with and guide the movement of the wings towards the adjacent wall parti¬ tions.

The thickness of the collar-shaped partition is selected to exceed the selected thickness of the wall structure.

The invention also shows that a yoke can be arranged at each side of the washer.

The present invention specifically shows that a first nut is to be arranged to the pin in order to provide a counter pres¬ sure surface; and that a second nut is arranged to serve as a clamping organ, in order to press, towards and into adjacent wall partitions, the edge partitions of the- yoke that relate to the outer wall structure, by plastically deforming the edge partitions of the yoke.

It is further shown that said wall structure is arranged to coact with the collar-shaped partition adjacent to a centrally-formed hole in said partition.

The invention is specifically suitable when the cavity is given a diameter that exceeds the diameter of the bolt by at

least a factor of three, such as four to five, and when said cavity is at least partially adapted to be filled with concrete or similar materials.

It is further shown that the bolt is to be arranged to extend out of the cavity above a resilient washer, in order to coact with a bar or a similar apparatus.

It is further shown that said cavity is to be given a centred bottom-related recess, with which the inner end of the bolt can coact.

ADVANTAGES

The foremost advantage that can be regarded as characterizing a clamping arrangement, according to the present invention, is that conditions have been created for satisfactorily clam¬ ping a bolt into a cavity, even when the diameter of the cavity is selected to exceed the diameter of the bolt; more- over, the bolt can be used to bear a load before the concrete, which is filled into the cavity, has been burnt.

The primary characteristic features of a clamping arrange¬ ment, according to the present invention, are set forth in the characterizing clause of Claim 1.

BRIEF DESCRIPTION OF THE DRAWINGS

Some of the embodiments currently proposed, which present the characterizing features of the present invention, will now be described with reference to the accompanying drawings, in which

Figure 1 shows in side view, and partly in section, an arrangement that is embedded in a concrete base whose form is previously known, regarding a bolt that is firmly fixed in a cavity whose diameter considerably exceeds—by about four times--the diameter of the bolt used;

Figure 2 shows in side view, and in section, an embodi¬ ment of the present invention, where a clamping arrangement is inserted into a cavity in a concrete base before it is used for clamping;

Figure 3 shows, much the same as Figure 2, a second embodiment with an alternative set of yokes;

Figure 4 shows in side view, and in section, one of the yokes that is used in Figures 2 and 3;

Figure 5 shows in perspective view, a first alternative embodiment of the yoke, with two partially cone- shaped diametrically-opposed wings;

Figure 6 shows in perspective view, a second embodiment of the yoke, with four diametrically-opposed plane wings;

Figure 7 shows in perspective view, a further embodiment of the yoke, with two diametrically-opposed plane wings;

Figure 8 shows in perspective view, a washer, or a counter pressure surface, adapted to a yoke according to Figure 7;

Figure 9 shows in perspective view, a washer, or a counter pressure surface, formed to be adapted to a yoke according to Figure 6;

Figure 10 shows in side view, and in section, the embo¬ diment according to Figure 2, in a clamping position and with the cavity filled with concrete.

DESCRIPTION OF EMBODIMENTS AT PRESENT PREFERRED

Figure 1 is a side and partially sectional view of a previo¬ usly known embodiment of a fixed bolt 1 in a cavity 2.

The cavity 2 is drilled in a previously known way in a concrete base 3, whose diameter "d" is ordinarily selected to 80 or 100 mm.

The bolt 1, with a diameter of 20 to 25 mm, and a washer, with a diameter that corresponds to the diameter of the cavity 2, is inserted into the newly-formed cavity 2.

The cavity 2 is then filled with a concrete mass 5, which is left to burn for a few days.

A bar 6 can be applied to the upper part la of the bolt 1; then, through a washer 7, the bar 6, by means of a nut 8, can be tightened to the concrete base 3 through the concrete mass 5.

This process is time-consuming, particularly because of the time that is needed for the concrete mass 5 to harden. Also, because the wall partitions 2a of the drilling are smooth, they do not provide good fixation between the outer surface 5a of the concrete mass 5 and the surface 2a.

Adapting the depth of the cavity 2 so that it is somewhat larger than the diameter "d" is not unusual.

A presently proposed first embodiment of a clamping arrange¬ ment 10, adapted to a cavity 2 and intended to be able to

coact firmly with several wall partitions 2b, 2c that belong to the cavity, consists of a bolt 1 or pin with associated screw thread 1' ; at least one nut 11 in coaction with the screw thread 1' ; a washer 12 or means to provide a counter pressure surface that encloses the bolt 1; and a yoke 13 that encloses the bolt 1 and is fitted between the washer 12 and the nut 11.

The outer periphery of the yoke 13 and the inner periphery of the cavity 2 are adapted to one another so that the yoke can be brought into a clamping coaction with said wall partitions 2b, 2c as the nut 11 is rotated around the bolt 1 or vice versa.

Although the cavity 2 is normally given a cylindrical form and the washer is normally given an outer circular or cylin¬ drical form, it is obviously within the scope of the inven¬ tive thought to give other forms to the cavity, the washer, and the yoke; for example, an elliptical, square, or triangular form.

In Figure 2, a second nut 11a is shown. This nut may also be exchanged with a fixed support to the bolt 1, or may consist of a bolthead, which preferably is allowed to rest against the bottom partition 2e of the cavity 2.

A second embodiment is shown with reference to Figure 3, having a washer 12; a yoke 13 arranged above the washer; a first nut 11 that coacts with the. yoke; a second yoke 13' arranged below the washer 12; and a second nut 11a or a support as illustrated in Figure 2.

In this embodiment, a rotation of the nut 11 will affect the two yokes 13, 13' so that they coact with the surface parti- tions 2b, 2c and 2b', 2c' respectively.

As a further embodiment, Figure 3 shows that the yoke 13 can

be removed and a nut 11, illustrated with dotted lines, can be allowed to act directly upon the washer 12.

For both embodiments, according to Figures 2 and 3, it is shown that the upper part la of the bolt 1 coacts with a nut 8 and squeezes a bar 6 through a resilient washer 7 and a nut 8'.

With reference to Figure 4 a first embodiment of a yoke 13 (13') is shown in side view. This yoke presents a partition 41 in the shape of a collar, which is oriented around and adjacent to the bolt 1, and a wall structure 42, which diverges from said collar-shaped partition.

The wall structure 42 and said collar-shaped partition 41 are formed as a single integrated unit.

In a non-coacting position the wall structure 42 is oriented, relative to the wall partitions shown in Figure 4, at an angle "a" which exceeds 45', relative to the centre line 1'' of the bolt.

The embodiment shows that the angular value is selected to 60' . However, variations within the range of 50" to 75 ^' are acceptable, depending on the tolerances selected between the outer peripheral edge 42a of the yoke 13 and the inner sur¬ face 2a of the cavity. A normal tolerance is between 1 and 10 mm, preferably between 4 and 8 mm; for example, 6 mm.

Figure 4 illustrates that the wall structure 42 is formed from two plane wings 43, 44. The number of wings can be selected from two to six.

With reference to Figures 5, 6, and 7, said wall structure is illustrated in the form of wings that are diametrically oppo¬ sed to one another. However, an embodiment with three wings falls within the scope of the inventive thought.

The embodiment according to Figure 5 is intended to illu¬ strate two diametrically-oriented wings 51, 52 whose curved shape is adapted to form a conoidal frustum with partly circular peripheral edges 51a, 52a.

Also, the embodiment in Figure 7 illustrates two opposed wings 51', 52', whose partitions 51a', 52a' are arranged to be able to coact with a slot 71 in a washer 12 according to Figure 8.

The washer 12 ought to be given the form illustrated in Figure 9, where two slots 81, 82 are oriented in an angle relative to each other, when four wings 61, 62, 63, 64 are used, according to the embodiment in Figure 6.

Note: a yoke 13, as shown in Figure 6, can very well be used with a washer 12, as shown in Figure 8.

The thickness of the collar-shaped partition 41 is selected to exceed the selected thickness of the wall structure 42, in order to create the conditions necessary for deforming forces to act within the area 42 rather than pressing the yoke 13 towards the screw thread 1' .

Thus, the embodiments according to the present invention can be regarded as consisting of a first nut 11, which is arran¬ ged to the bolt 1 to provide a counter pressure surface; and a second nut 11a, which is arranged to serve as a supporting organ, in order to press, towards,the adjacent wall parti- tions 2b, the edge partitions 42a of the yoke 13 that relates to the outer wall structure 42, by plastically deforming the edge partitions of the yoke.

Said wall structure 42 is arranged to coact with the collar- shaped partition 41 adjacent to a centrally-formed hole 41a in said partition.

The bolt 1 is arranged to extend out of the cavity 2 above a resilient washer 7 in coaction with a bar 6 or a similar apparatus, in a previously known manner.

Said cavity 2 is given a centred bottom-related recess 2f, with which the inner end lb of said bolt coacts.

Figure 10 is intended to illustrate the position of the parts when the clamping arrangement 10 is affected into a fixed position with the cavity 2 and its wall partitions 2b, 2c.

The nut 11 evidently presses the yoke 13 to such an extent that the wall structure 42 is deformed into a plane with the washer 12 or the support by which the peripheral edge 42a of the wall structure 42 is pressed into the wall partitions 2b, 2c of the, cavity 2, thereby securing a firm anchorage.

The penetration depth ought to be 1 to 8 mm, preferably between 3 and 6 mm; for example, 5 mm.

Ideally, the yoke 13 is selected from spring steel, whereas the washer can be made of iron.

The cavity can be filled with a concrete mass (5) after the bolt has been inserted as indicated.

It will be understood that the invention is not restricted to the illustrated exemplifying embodiments thereof and that modifications can be made within the scope of the inventive thought illustrated in the following claims.

The described embodiment can obviously vary so that the dia¬ meter "d" of the cavity 2 can be selected to be greater than the diameter of the bolt or pin that is used. The thickness of the wall structure may be selected with a thickness that prevents buckling tendencies according to the first buckling case of the wall partition.