Adjustable clamp for holding objects securely in position

Technical Field:

The present invention relates to an adjustable clamp for holdi objects-securely in position comprising at least one arm which exhibits one articulated arrangement arranged at each of t two ends of the arm, said articulated arrangement exhibiting t pivot pins arranged at an angle to each other, whereby said object so arranged as to be held securely by means of a clamping arrangeme attached to the articulated arrangement.

Technical Problem:

The purpose of the present invention is to propose an adjustab clamp by means of which objects may be set in a large number different positions and may be aligned in different direction Examples of such objects include so—called stops which are intend to hold workpieces in position during machining operations, f example when drilling at a pre—determined point. For this purpos the clamp is adjusted in conjunction with the stop after the fir workpiece has been placed in the desired position, whereupon the st is tightened against a suitable edge or surface. Once this has be done, a series of identical workpieces can be located in identic positions enabling a repeatable machining operation to be performed.

Solution:

The aforementioned purpose is achieved by means of a clamp whic is characterized in that each articulated device exhibits, free t move in relation to the arm, an articulated body with a curve articulated surface which is in contact with and is so arranged as t move relative to a corresponding curved articulated surface in a articulated component attached to the ends of the arm and with a fla articulated surface which is in contact with and is so arranged a to be capable of being turned relative to a corresponding fla

-BURE

O P

surface, in that one of the pivot pins in each articulate arrangement extends through the articulated component and th articulated body and forms a releasable locking arrangement for th arm and for the clamping arrangement by being adjusted between locked position in which the articulated surfaces are tightly clampe to each other in a pre—set position between said pivot pins and released position in which the articulated surfaces are capable o moving relative to each other, and in that the articulated component of the arm are executed in the form of hook—like components, each o which is open to the side in its own particular direction relative t the longitudinal direction of the arm.

Description of the Drawings:

The invention is described below in greater detail in relatio to a couple of typical embodiments with reference to the accompanyin drawings, in which Fig. 1 shows a side view of the clamp i accordance with the invention in a first typical embodiment, shown i two different positions; Fig. 2 shows a view from above of the clam in accordance with Fig. 1, shown in two different positions; Fig. and Fig. 4 show two perspective views of the clamp in accordanc with Fig. 1, whilst Fig. 5 shows a practical application i conjunction with a drilling operation. Fig. 6 shows the clamp in second embodiment in two different positions, and Fig. 7 and Fig. show the clamp in accordance with Fig. 6 in two different perspectiv views.

Best rooxle of .carrying out the invention:

The clamp in accordance with the first embodiment illustrated i Figs. 1—5 consists of an arm 1 , each of the ends 2, 3 of which i provided with its own articulated arrangement 4, 5 . Each and ever one of the. articulated arrangements 4, 5 exhibits a first pivo pin 6, 7 which is horizontal in the typical embodiment shown and a second pivot pin 8, 9 which is vertical in the typica embodiment shown with regard to one of the articulated arrangement 4 but which is capable of being set to various angles along variou vertical planes with regard to the second articulated arrangement 5

-BUR

O

The first pivot pin 6, 7 in the two articulated arrangements 4, is executed in the form of a cylindrical body, whereas the seco pivot pin 8, 9 is executed in the form of a screw which in t typical embodiment shown in one of the articulated arrangements" " is an Allen screw which extends through a transcurrent bore 10 the pivot pin 6, 7 . The first pivot pin 6, 7 thus exhibits articulated surface 11 in the form of a cylinder jacket. The arm exhibits- at either end an articulated component 12 forming part the articulated arrangement 4, 5 , said articulated component wh viewed from the side having a hook—like appearance and exhibiting similarly curved, concave articulated surface 13 in the form of cylinder jacket which is designed to make contact with t articulated surface 11 of the pivot pin 6, 7 . In the articulat component 12 is arranged a long groove 14 , as may best appreciated from Fig. 3 and Fig. 4, through which the pivot pin 6, extends.

In each and every one of the articulated arrangements 4, 5 i also incorporated an articulated body 15 which exhibits a concav articulated surface 16 in the form of a cylinder jacket, designe to make contact with a convex articulated surface 17 in the form o a cylinder jacket on the articulated component 12 of the arm i each and every one of the articulated arrangements 4, 5 . These tw articulated surfaces 16, 17 exhibit essentially the same radius o curvature in each and every one of the articulated arrangements whilst the articulated surfaces 11, 13 exhibit essentially the sam mutual radius of curvature. All the curved articulated surfaces 11 13, 16, 17 are coaxial with the pivot pin 6, 7 . The articulate bodies 15 also exhibit a flat articulated surface 18 intended t slide against a second flat surface 19,-20 so as to permit articulate movement about the pivot pins 8, 9 . The articulated surfaces 11 13, 16, 17 in the form of a cylinder jacket are intended to slide i pairs against one another in order to permit articulated movemen about the pivot pins 6, 7 . The articulated bodies 15 exhibit transcurrent bore 21 for the pivot ^" pins 8, 9 -

The lower articulated arrangement 4 in accordance with th

first typical embodiment is executed in the form of an articulate holder which is capable of being moved along a gui arrangement 22 , such as is found, for instance, on machine tool such as boring machines for the purpose of permitting the attachmen of, for instance, clamping arrangements such as collet jaws o similar arrangements for holding the workpiece securely in positio The guide arrangement 22 is executed with a channel 23 , fo instance of T—shaped cross—section and with a narrower part whic exhibits a groove 24 open towards the top, through which th vertical pivot pin 8 in the articulated arrangement 4 extends an which with its lower end is in threaded engagement with a suitabl square nut 25 which is able by means of its upward—facing guid surface 26 to slide against, and by tightening up the Allen scre 8 to be clamped against a downward—facing guide surface 27 in th guide arrangement 22 . The shape of the nut 25 prevents i from turning at the same time as a turning motion is imparte to the Allen screw 8 .

By means of the articulated arrangement 4 which serves as a articulated holder the clamp may be moved to any desired positio along the guide arrangement 22 with the Allen screw 8 whic serves as a pivot pin slackened off slightly. With the screw in tha position, the arm 1 may be set to any desired angle of articulatio about both the vertical pivot pin 8 and the horizontal pivot pin that is to say it may be articulated to any desired angle in th vertical plane and to any desired angle in the horizonta plane. Articulation about the . vertical pivot pin 8 may tak place through, a full 360 degrees, whereas articulation abou the horizontal pivot pin 6 takes place within a certai given angular interval, in respect of which Fig. 1 shows. th two end positions in the typical embodiment in question. Th solid line shows the lower end position with the arm 1 i contact with the guide arrangement, and the dotted and dashe lines show the upper end position with the head ^• 28 of th screw forming a stop against a flat contact surface 29 on th arm 1 . The head 28 of the screw

-BURE

OAP

is in this instance slightly recessed into the horizontal pivot p 6 , but is intentionally not entirely recessed so as to enable it serve as a stop permitting the Allen screw to be tightened a slackened by means of a hexagon key. The stop will also prevent a unintentional articulation of the arm 1 to the point at which t articulated joint will fall apart.

By activating one and the same element, that is to say t vertical pivot pin 8 , it is possible for locking to take place the articulated clamp on the guide arrangement 22 and in additi for the arm ^' 1 to be locked relative both to the horizontal piv pin 6 and to the vertical pivot pin 8 , thereby achieving the ve effective and stable locking of the arm 1 in its desired position.

The second, articulated arrangement 5 has its hook—lik articulated component 12 facing in the opposite direction i relation to the articulated component 12 in the articulate arrangement 4 . In this way the convex articulated surface 17 o the articulated component faces essentially upwards, with th articulated body 15 resting on the articulated component 12 an in turn supporting a clamping arrangement 30 which exhibits•sai flat surface 20 , which is in contact with the flat articulate surface 18 of the articulated body 15. The pivot pin 9 extend through a transcurrent bore 31 in the articulated body 30 through the transcurrent bore 21 in the articulated body 15 ^" and th groove 14 in the articulated component 12 and is screwed into th horizontal pivot pin 7 by its end which is provided with a scre thread. The pivot pin 7 thus exhibits a bore provided with a scre thread which may, for example, be transcurrent. The other bores nee not be provided with a screw thread. In this embodiment, the pivo pin 9 in the articulated arrangement 5 is not an Allen screw, bu is a slotted— ead screw or a threaded pin which, at its upper end exhibits an operating lever 32 , by means of which the pivot pin may be turned for the purpose of being tightened and slackene The operating -lever 3-0 ^~ is capable in a previously disclosed fashio by imparting a movement in the longitudinal direction of the pivo pin 9 of being moved between different articulated position without the need to cause the pivot pin 9 to turn with it, enablin the operating lever 32 to be set to various positions of engagemen

enabling the pivot pin to be brought into an appropriate positi depending on the space available.

The clamping arrangement 30 is essentially cylindrical in for in the embodiment shown and is also provided with a transcurrent bor

33 , as may best be appreciated from Fig. 2, which ^" extends a right angles to the pivot pin 9 and eccentrically from it. Throu this bore ^' 33 extends transversely across the pivot pin 9 a sl

34 which is so dimensioned as to permit the bore 33 to restricted to a certain extent by a head 35 of the pivot pin 9 which is forced into a depression in the clamping arrangement 30 .

The clamp in accordance with the invention is so arranged as t be capable in a number of different positions of supportin an object which, ^• in the embodiment shown, is in the form of rod-shaped clamping arm 36 extending through the bore 33 , sai arm being of circular cross—section in the embodiment shown. Thi clamping arm is so arranged as to be tightly secured to the clampin arrangement 30 in the desired position and represents^ for example the object which is intended to be supported by the clamp i accordance with the invention in the desired position and in th desired direction. The clamping arm 36 in the embodiment shown i executed in the form of an extendable arm intended to serve as stop when machining the workpiece. The extendable arm 3 accordingly exhibits at either end a stop organ 37, 38 . The firs stop organ exhibits a flat front contact surface 39 and a flat rea contact surface 40 and also a contact edge 41 ^* . The second sto organ 38 is in the form of a spherically rounded end part to th extendable arm 36 . The extendable arm 36 is capable of bein turned through its ability to be removed from the bore 33 , turne and inserted into the bore from the opposite direction. At the sam time the clamping arrangement 30 is capable of being turne - through 360 degrees about the pivot pin 9 enabling the bore 33 t be positioned in any desired direction, and even in one and the sam direction but on either side of the pivot pin 9 . The extendable ar 36 can thus be turned in such a way that the stop organ 37 or may be selected depending on the nature of the surface or the edge the workpiece against which the stop organ is to make contact.

The articulated arrangement 5 thus permits the adjustment the clamping arm 36 to any desired angular position in both t horizontal plane and the vertical plane by means of the operati lever 32 after having slackened off -the articulated arrangemen that is to say by screwing out slightly the pivot pin 9 from t bore 10 in the pivot pin 7 , by causing the clamping arrangeme 30 to turn about the pivot pin 9 by sliding the fl articulated surfaces 20, 38 against each other and by sliding t articulated surfaces 11 and 13 and 16 and 17 in the form cylinder jackets against each other. With the articulated arrangeme 5 released, the clamping arm 36 will also be released so that i may be moved in its longitudinal direction to any desired positio For the purpose of placing the articulated arrangement 5 in t locked position, the operating lever 32 is turned in a sense whi will cause it to be screwed further into the bore 10 in the piv pin 7 , when the pivot pin will be clamped against the articulate component 12 , thereby creating such friction both in th articulated surfaces 11, 13 and 16, 17 in the form of cylinde jackets and in the flat articulated surfaces 20, 38 that lockin will take place, that is to say that the pivot pin 9 will be hel securely in the desired position and that the clamping arm 36 wil be held in the desired angular position. In the case of the uppe articulated arrangement, the ability to articulate in the vertica plane will be limited by the contact of the pivot pin 9 with th stop at either end of the groove 14 . At the outer end of the groov the stop 42 is formed by a pin extending transversely across th groove, said . pin extending through a bore in the articulate component 12 of the arm 1 , whilst the second stop 43 (see Fig 3) is formed by the inner end of the groove 14.

Locking by means of the operating lever 32 takes place in tw locking stages, however. The first locking stage occurs in accordanc with the above in conjunction with the first tightening operation b means of the operating lever, when the angular positions i accordance with the above are fixed, whilst the clamping arm 36 i still capable of being moved in its longitudinal direction. Afte further tightening by means of the operating lever 32 , the clampin

arm 36 will also be held securely by the slight compression of th components of the clamping arrangements 30 , which are separated b the slot 34 . The depth of the slot is, in fact, calculated i relation to the flexibility characteristics of the material used i the clamping organ, which may be made from a light alloy, fo instance, so that locking will first occur in the sliding surfaces o the articulated arrangement 5 , followed by locking of the arm i the bore-.

Fig. 3 and Fig. 4 show .the appearance of the arm 1 and th sliding ^' surfaces of the articulated arrangements 4, 5 , whic provide exceptionally stable and effective locking due to the grea width of the articulated surfaces.

Fig. 5 shows an application in which use is made of the clamp i accordance with the invention as a stop by means of which t determine the position of a workpiece 44 during the machining o said workpiece, in this case drilling by means of a drilling machin 45 . The purpose of the stop is to permit a machining Operation, i this case drilling, to be performed at one and the. same point on al the workpieces when driLling a large number of workpieces 44 whic are identical with each other. For this purpose, the first workpiec 44 is placed in the desired position so that the machining operatio may be performed at the correct point, with the clamping arrangemen in accordance with the invention initially being retracted from th position indicated in Fig. 5. The workpiece 44 is raised to th desired height by means of packing pieces 46 and is prevented fro moving in directions across the transverse plane of the paper b means of a vice, (not shown) or by means of an adjustable stop in th form of an adjustable supporting surface which is brought int contact with the workpiece. The clamp and the stop in accordance wit the invention are then advanced with the two articulated arrangement 4, 5 in the released, i.e unlocked, position in which the clamp ma be moved along the guide . 22 into the appropriate position i relation to the workpiece 44 . For this purpose, the lowe articulated arrangement 4 is tightened up slightly so as to give i a certain degree of location, yet ^' still to permit articulate movement should this be necessary during the adjustment of the clamp

The upper articulated arrangement 5 is left in the released st so that the clamping arm 36 may be set to the desired angu position by turning it about both the horizontal pivot pin 7 the pivot pin 9 . Use is made of the rounded stop organ 38 in t case, although the second stop organ 37 could also be used in t instance. In the workpiece .44 shown, the position of the bore wh is to be executed is dependent on the position of a rec 47 , which in this case is cylindrical, for which reason the s organ 38 is brought into contact with an internal corner of s recess 47 , that is to say with both the edge surface 48 and t bottom surface 49 . The necessary adjustment is best made in th case with the clamping arm 36 being both, adjusted in an angul sense and advanced in a longitudinal sense, whereupon locking of t clamping arm takes place against both angular movement a longitudinal movement. When adjustment is to be made directly towar a surface, it is preferable for the aforementioned locking operati to take place in two stages, with the angular positions bei adjusted initially, followed by the advancement of the clamping a to the point at which the contact organ 37 or 38 comes into co ^' nta with the surface in question. The rounded contact surface 48 or t rounded stop organ 38 may also be used, for example, in bores permit the introduction of the clamping arm 36 into.bores and determine the position against any of the surfaces of the bores. T aforementioned rearward—facing contact surface 40 may be used the event of the surface of the workpiece facing away from the cla being most suitable for holding the workpiece in position. Once t clamp and the stop organ have been adjusted, the position of t workpiece 44 can be reproduced for all subsequent workpieces, whi will require to be advanced up. to the stop organ, in so doi assuming the same position as the first workpiece. In this way t machining operations will take place at one and the same point each workpiece. Thus, in the case illustrated here, the recess exhibits a sideways—facing opening which enables the workpiece to removed without the need to move the clamp or the stop organ.

Figs. 6, 7 and 8 show a second embodiment of the clamp i accordance with the invention. In accordance with this embodimen

I J

the clamp is provided with a further arm 50 , which is identica with the first arm and similarly exhibits two articulate arrangements 51, 52 which function in principle in an identica fashion to the articulated arrangements 4, 5 of the first arm. Fo this purpose, the square nut 25 is transferred from the pivot pi 8 of the first arm to the pivot pin 53 of the second arm, whils the pivot pin of the first arm extends through the articulated bod 54 of -the second arm in the articulated arrangement 52 and i screwed into the horizontal pivot, pin 55 of the second arm 50 Between the two articulated bodies 15, 54 which face each other i thus formed the flat point of articulation between the fla articulated surface 18 of the upper articulated body 5 and th flat articulated surface 56 of the lower articulated body 54 . I this way, a double articulation is thus achieved between the two arm 1, 50 with a common pivot pin 8 and each of the horizontal pivo pins 6, 55 . The double articulation thus provides for angula adjustment between the two arms 1, 50 in the vertical plane an also for angular adjustment in the horizontal plane. In addition parallel movement is also provided between the two arms through th ability of the common pivot pin 8 to be adjusted to a variety o angular positions.

The embodiment with two inter—connected arms 1, 50 illustrate in Fig.

6, Fig- 7 and Fig. 8 offers a greater reach and a greater range o adjustment for the' object which is to be supported. Dotted and dashe lines are used . to indicate the end position for the angula adjustment between the two arms in the vertical plane. Thus, in Fig 6, the object shown is in the form of a stop, as in the previou embodiment, whereas Fig. 7 and Fig. 8 show a more general view of clamping arm 57 which can be used to secure in position any othe object. Typical objects are measuring instruments which must be hel securely in a precisely determined position, which may vary from cas to case. Examp-les of such instruments are a dial gauge for .-_ measuring changes in level or irregularities in the surface of material. Other examples are lamps for photography, for instance which must be adjusted to various positions which may vary from cas to case.

In a corresponding fashion, the number of arms may be increas further depending on the need for adjustment and reach associat with the clamp. The material used for the arms and the articulat bodies may be a light metal alloy or some other metal, whereas t pivot pins and the articulated bodies are best executed in steel. T operating lever may be executed in plastic, for instance, which m also be used for certain other component parts. It is importan however, for the material used not to be excessively flexible, b to be selected in such a way that the object in question can be he in the desired position without excessive changes in position.

The invention is not restricted to the typical embodimen specified above and illustrated in the drawings, but may be modifi within the context of the following Patent Claims. For instance, is conceivable for the arms 1, 50 and the articulated bodies to designed with a different appearance. It is also conceivable for t surfaces in the form of a cylinder jacket to be replaced double— urvature surfaces or other rotationally symmetrical generat surfaces. Also, the articulated clamp on the guide arrangement may executed in a different fashion depending on the particul application. The clamp may be replaced by a clamping arrangement f clampingto a table top or similar. More than two arms may connected together in a modular system in which the number of ar is selected to suit each individual case. Additional clamp orga may be inserted between two arms, that is to say between t articulated bodies 15 , for the purpose of supporting severa objects simultaneously in different positions. In the abov embodiment the clamping arms 36 have been assumed to be the objec which is supported and whose position is determined. In the event o other objects being intended, the clamp should also be fitted with rod—like component which is held in place in the same way as th clamping arm 36 and to which the objects in question are attached Alternatively, the object may be fitted with a rod—like shaft.

^" BU

OM