DE9003030U1 - Clamping jaw with sleeve - Google Patents

Description

European Patent Attorney» .'.*.,* ',.·· &Sgr;" ",'.' ·

DtInq.MHdd

Authorized representatives Patent attorneys · Lange Strasse 51 ■ D-7000 Stuttgart 1 at the European Patent Office

GH 5957/40

HYDAC Technology GmbH, Postfacn 1251, 6603 Sulzbach/Saar

Clamping jaw ^t sleeve

The invention relates to a clamp with at least two clamping jaw parts which together define at least one receiving space, in particular for receiving a fluid-carrying part, which are made of a material that tends to flow, in particular plastic, and which are supported on counter bearings which are connected to one another via connecting means, preferably in the form of screws. Such clamps are used, among other things, in vehicles, in particular on excavators, crane vehicles or the like, and there they receive fluid-carrying parts, in particular pipes or the like, for guiding them within the receiving space formed by the clamping jaw parts. In order to achieve a firm hold of these fluid-carrying parts within the clamp, the plastic clamping jaw parts are clamped against the fluid-carrying part by means of connecting means, usually in the form of screws, in order to exert a pressing force on the fluid-carrying part.

Telephone (0711) 221091 Poätgirb ,StuOghrt 03LZAt)OIO'! 70) .7"2U-7t)0

Telex 7 22312 difilwo ti) DeurSthrt BahK Stuttgart: (BI Z'600 70070) !1428 R30 Telephone information and orders are

Fax (0711) 22 87 80 Slulfg'artei'Bankfi!LZibO090100) 1597436 only after written confirmation

- ² - GM5957/40

Thermal stress and/or vibrations, which occur particularly in the engine area of such vehicles, can lead to the clamping jaw parts breaking due to the tendency of the plastic to flow and creep, which leads to the fasteners in the form of the clamp screws coming loose, which can then be lost completely. This leads to the fluid-carrying part falling out of the clamp and serious subsequent damage to the vehicle.

The present invention is based on the object of creating a clamp with which these problems can be avoided.

This task is solved by a clamp with the features of claim 1. Due to the fact that, according to the characterizing part of claim 1, support means are provided between the counter bearings, which preferably keep the counter bearings at a distance with a predeterminable preload, a fixed frame is formed with the parts of the clamp, namely the counter bearings, the connecting pieces and the support means, the geometry of which does not change, even if the clamping jaw parts accommodated within the frame begin to settle due to their tendency to yield. The connecting means, preferably in the form of screws, can therefore not come loose under any circumstances, since the support means do not cause any change in the condition of the screw connection. Since the frame in question always remains unchanged as a type of framework, even in a case where the plastic Velcro jaw parts were completely destroyed by settling phenomena, the fluid-carrying part originally accommodated in the receiving space would not be able to fall out of the clamp, but would instead remain within the frame.

³ GM5957/40

In a preferred embodiment of the clamp according to the invention, the respective support means is a sleeve, preferably at least one tube, with a low tendency to flow and creep. This provides an essentially rigid support means with which a constant preload can be exerted on the counter bearings braced against each other, which ensures that the torque with which the connecting means in the form of the screws for clamping the fluid-carrying part within the receiving space formed by the clamping jaw parts are tightened does not decrease and thus loosening of the connecting means is avoided.

In a further preferred embodiment of the clamp according to the invention, at least some of the support means are penetrated by a connecting means, whereby preferably some of these support means are guided at least within a clamping jaw part of the clamp. This results in a particularly space-saving design of the clamp according to the invention.

In a particularly preferred embodiment, at least before the fluid-carrying part is secured in the receiving space, the respective clamping jaw parts are separated from one another by gap-like distances, which on the one hand facilitate the insertion of the fluid-carrying part into the receiving space of the clamp and on the other hand ensure that a pressing stress can also be exerted on this part by means of the connecting means via the counter bearings and the clamping jaw parts.

If the respective counter bearing is made of a plate, preferably made of a material with a low tendency to flow and creep, with at least one contact surface that is intended for contact with a clamping jaw part, the pressing force exerted on the clamping jaw parts via the connecting means can be distributed evenly along the

" ⁴ GM5957/40

boundary wall of the clamp's receiving space and thus to the fluid-carrying part to be accommodated.

In a preferred embodiment of the invention, these plates have at least some extensions against which the support means are placed and which are intended for establishing a firm connection with the connecting means, preferably having an internal thread for this purpose. These extensions can be specially adapted to the connecting means used in the clamp, in particular their internal thread can be adapted to the external thread of the screws used in each case, so that accordingly the plates to be used as counter bearings can remain the same for the most varied types of clamps with clamping jaw parts and only the extensions change, which is cost-effective.

In the following, the clamp according to the invention is explained using two exemplary embodiments shown in Fig. 1 and 2. If the second embodiment according to Fig. 2 has the same parts as in the first embodiment, these parts are represented with reference numbers increased by 100 .

It shows:

Fig. 1 shows a section through a first embodiment of the clamp;

Fig. 2 partly in view, partly cut away, a second embodiment of the clamp, which is suitable for holding two fluid-carrying pipes.

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The clamp shown in Fig. 1 has two clamping jaw parts 10 which together define a receiving space 12 which is intended for receiving a fluid-carrying part, here in the form of a pipe 14 shown in dash-dotted lines. The clamping jaw parts 10 are made of a plastic which, as a material property, generally tends to creep and flow. The clamping jaw parts are supported on counter bearings in the form of plates 16 which have a contact surface 18 which is in contact with the surface of the respective clamping jaw part facing it . The plates 16 are selected in such a way that they either end flush with the clamping jaw parts 10 towards the outside ¹ or have a projection, as shown in Fig. 1 for the upper plate 16 and the lower plate 16 respectively.

These plates 16 are made of a material with a lower tendency to flow and creep than plastic.

p and consist in particular of a steel material.

& The plates 16 extend essentially transversely to the

I Longitudinal axis 20 of the tube 14. At the opposite

f ends of the essentially rectangular plates

j; 16 there are two through holes 22 per plate,

I whose diameter depends on the amount of material to be

ig connecting means in the form of screws 24 is selected.

I The holes 22 correspond to holes 26, which in diameter

I knives are larger, the two clamping

ff jaw parts 10 continuous.

I in these two holes 26 of the clamping jaw parts 10 is

I a tube 28 is used as a support, which

y as shown in Fig.l an up and down

I forms a hollow cylinder open towards the inside and which is also made of

ö a material with lower flow than plastic

H and creep tendency, for example from a steel-I material with the designation St 52.3.

- 6 - · GM 'j957/40

The tubes 28 shown in Fig. 1 approximately to the right and left of the center of the picture extend over both clamping jaw parts 10 and are each penetrated by the connecting means in the form of the screw 26 of the usual type. The lower of the two plates 16 shown in Fig. 1 has two sleeve-like extensions 30 at their opposite ends, which are provided with an annular shoulder 32 and engage in the bore 22 assigned to them in such a way that each extension 30 with its shoulder 34 running along the side comes into contact with the contact surface 18 facing the clamping jaw parts 10. These extensions 30 have an essentially continuous internal thread 36 which corresponds to the external thread 38 of the screws 24 used and is in engagement with them.

The plug-like extensions 30 are firmly connected to the lower of the two plates 16 shown in Fig. 1 by means of a welded connection 40. It is also conceivable here to provide the annular shoulder 32 with an external thread (not shown), which would then engage in a corresponding internal thread of the respective bore 22 for securing the extensions 30 to the plate 16. The bores 22 in the two opposite plates 16, which are assigned to one half of the clamp as seen from the center of Fig. 1, are aligned with one another together with the bores 26 in the clamping jaw parts 10, and the longitudinal axes 42 of each screw 24, each tube and each extension 30 essentially coincide there and are arranged perpendicular to the longitudinal axis 20 of the tube 14. Furthermore, each tube 28 is at least in contact with the bore wall of the bores 26 in the clamping jaw parts 10 with its outer circumference and with the screw 26 passing through it with its inner circumference, whereby when the screws 26 of the clamp are tightened, a pressing force is generated along the surfaces of this contact.

At the point where each screw 24 penetrates, the clamping jaw part 10 shown in Fig.l above has

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On the side facing the contact surface 18, the clamping jaw part 10 has a recess 44 with a circular cross-section, the diameter of which is larger than that of the holes 26 in the clamping jaw parts 10, which makes it easier to insert a tube 28. Likewise, the clamping jaw part 10 shown at the bottom of Fig. 1 has a corresponding recess for each screw 24 in the form of a recess 4G with a circular cross-section, into which the extension 30 can be inserted. In the embodiment of the invention shown in Fig. 1, each tube passes through both clamping jaw parts 1.0 and is supported with its two opposite ends 48 and 50 on the contact surface 18 of the plate IG shown at the top of Fig. 1 or on the top side 52 of the extension 30.

As can also be seen from Fig. 1, the two clamping jaw parts 10, with their surfaces facing each other, delimit a continuous gap 54 which lies essentially in the same plane as the longitudinal axis 20 of the pipe 14. As soon as an increasing torque is exerted on the two screws 24 using an appropriate tool, such as a wrench, the two counter bearings in the form of the plates 16 move towards each other and, accordingly, the two clamping jaw parts 10. This reduces the thickness of the gap 54 and an essentially uniform pressing force is exerted on the pipe 14 via the boundary wall of the receiving space 12, the cross section of which is expediently adapted to the cross-sectional shape of the part to be accommodated in the clamp.

With the application of the increasing torque, the two tubes 28 are also slightly compressed by the movement of the two plates 16 and accordingly exert a counterforce on the with the plates 16 which keep them at a distance. With the two plates 16 shown in Fig.l, the two screws 24, the two tubes 28 and the extensions 3 0, a substantially correct fit is made for me, in particular q &ugr; r3 given a dramatic frame, the spine geometry &ugr; nc! d &eegr; &eegr;

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applied torque, even if the two clamping jaw parts 10 should now settle during operation of the clamp. It is also clear here that if the clamping jaw part 10 shown in Fig. 1 below is completely destroyed, the plate 14 received in the receiving space 12 cannot fall out of the clamp, but comes into contact with the lower of the two plates 16. Falling out of the plate 14 from the clamp according to the invention is thus definitely prevented.

If the screws 24 used as connecting means change, for example in that they have a larger diameter in order to connect larger clamping jaw parts to one another, extensions 30 of a different design must be connected to the lower of the two plates 16 shown in Fig. 1, which even then does not need to be changed.

However, it is also within the scope of the invention to completely dispense with the extensions 30 shown in Fig. 1 and to screw the connecting means in the form of screws directly into a corresponding hole with an internal thread in the lower plate which can also be part of a larger wall, for example an engine housing wall. In this case, the respective tube no longer supports itself |

as before on the upper side of the process, but &idigr;

is extended to such an extent that it immediately .|

comes into contact with the contact surface of this plate facing it. This then leads to a largely symmetrical structure of the clamp according to the invention and the clamping jaw parts no longer need to differ from one another in their shape, which is on the one hand cost-effective in terms of their production and on the other hand makes the assembly of the clamp easier.

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The clamp shown in Fig. 2 has a total of four clamping jaw parts 110, which in pairs of two each delimit a receiving space 112. In addition to the plates 118 shown at the top and bottom in Fig. 2, which act as counter bearings, a plate 116 is inserted between the two pairs of clamping jaw parts as a further supporting bearing. This middle plate 118 has a hexagon nut 158 at the point where the connecting means in the form of a screw 124 passes through, at the ends of which an end of the tube 128 T is supported, which is divided into two in the embodiment shown in Fig. 2. This division into two also applies to Fig. 2. the connecting means in the form of the screw 124, which - in place of the hexagon nut 158 - has a separation point (not shown), whereby the screw 124 has a threaded piece at its mutually facing ends for engagement with the hexagon nut 158, which is shown visibly in Fig. 2 for the upper part of the screw 124 or the lower part of the screw 124 shown in Fig. 2 is firmly connected to the hexagon nut 158. The clamping of the removable pipes 114 takes place in a similar way to the first embodiment by applying a torque with a suitable tool to the respective screws 124.

It is also within the scope of the invention to use spacers, for example in the form of spacer disks (not shown), as counter bearings instead of the plates 16,116, which would be inserted between the screw head of the screws 24,124 and the tube 28,128, whereby their outer circumference is selected so that the respective spacer disk can be brought into contact with the side of the clamping jaw element 10 facing it in order to form the contact surface. This spacer disk could then also accommodate the extensions 30,130 in a corresponding development of the invention or with a

GM5957/40

The spacer disks 24, 124 can be provided with a corresponding internal thread and can be designed directly for engagement with the screws 24, 124. This type of spacer disk would then also have a certain diameter in order to form the contact surface with the other clamping jaw part 10. The support means can also be spring rings of the usual type, which exert the preload on the counter bearings. This allows an initial thermal load to be compensated for by the preload of the spring rings mentioned, but this still leads to a reduction in the torque originally applied and thus to a loosening of the screw connections. With further thermal loads, the preload decreases even further. This option, which is still within the scope of protection of the invention according to the wording of the main claim, is therefore preferably used where the thermal stresses are not too high.

The above description and the drawing are limited only to the specification of features that are essential for the embodiment of the invention. Therefore, to the extent that features are disclosed in the description and drawing and are not mentioned in the claims, they also serve, if necessary, to determine the subject matter of the invention.

Claims (6)

- &Pgr;&Igr; - RM 5957/40 claim e 1. Clamp with at least two clamping jaws (10,110), - which together define at least one receiving space (12,112), in particular for receiving a fluid-carrying part (14,114), - which are made of a material that tends to flow, in particular plastic, and - which are supported on counter bearings which are connected to one another via connecting means, preferably in the form of screws (24,124), characterized in that support means are provided between the counter bearings, which preferably keep the counter bearings at a distance with a predeterminable preload. 2. Clamp according to claim 1, characterized in that the respective support means is a sleeve, preferably at least one tube (28,128), with a low tendency to flow and creep. 3. Clamp according to claim 1 or 2, characterized in that at least a part of the support means is penetrated by a connecting means, preferably at least within a clamping jaw part (10,110), 4. Clamp according to one of claims 1 to 3, characterized in that at least before the fluid-carrying part (14,114) is fixed in the receiving space (12,112), the respective clamping jaw parts (10,110) are separated from one another by gap-like distances (54,154). 5. Clamp according to one of claims 1 to 4, characterized in that the respective counter bearing consists of a plate (16,116), preferably consisting of a material - 02 - GM5957/40 with a low tendency to flow and creep, with at least one contact surface (18,118) which is intended for a contact with a clamping jaw part (10,110). 6. Clamp according to claim 5, characterized in that the plates (16,116) at least partially have extensions (30,130) against which the support means rest and which are intended for establishing a firm connection with the connecting means, preferably having an internal thread for this purpose.