As used in this description the expressions"rear" and"front"and expressions with similar meaning are in reference to a normal placing of the brakes. Thus,"front" refers to the side facing the wheel, while"rear"refers to the side facing the interior of the vehicle. Thus, at least some part of the brake mechanism is normally to be received in the"rear"part of the caliper. The expression"axial" as used in this description is to be taken in relation to the rotational axis of the wheel (not shown in the draw- ings.) Prior Art In disc brakes having a fixed caliper the disc (s) is normally received floating or sliding in the axial direc- tion, but in some embodiments at least one disc is fixed in the axial direction. The disc (s) is moved directly into and out of contact with the brake pads. The number of brake discs may vary. Furthermore, the caliper may be used irre- spectively of in which way the brake is actuated. Thus, the brake may be e. g. pneumatically, hydraulically or electri- cally actuated.

Disc brake calipers of the prior art are usually pro- duced as large single-piece units, which leads to rela-

tively heavy and spacious parts that may be cumbersome and costly to produce, handle and repair. The production of the calipers of the prior art often involve machining in con- fined spaces for which specially designed tools may have to be used. In assembly the brake mechanism is often inserted into the caliper with a tight fit. This means that the brake mechanism has to be more or less turned and twisted to come into the designed space. However, as both the mechanism and the caliper are relatively heavy this will put a rather large stress on the assembling personnel.

Analogous problems occur at maintenance and repair. The large units have also drawbacks regarding logistics and distribution.

Another problem is how the brake force is transferred from the brake pads to the axle of the vehicle. The"flow" of the brake forces will effect the stability of the brake and ultimately the performance, vibration and noise of the brake.

A further problem is how to attach the caliper to various kinds of brake torque support means of the axle and within the space available at the wheel end of the axle.

The Invention Different objects of the present invention are to re- duce the weight, the space needed by the brake and the costs for production, handling and maintenance. There is also a desire to facilitate assembly and mounting of the brake.

A further object is to improve the stability of the structure influenced when braking forces are applied and accommodate for different attachments to the axle.

According to the present invention a disc brake for a vehicle is arranged having a fixed caliper and one or more brake discs. The caliper is formed of two or more parts.

One part forms a torque support member or an extended

mounting means. At least parts of a brake mechanism are mounted as a unit from the front (disc) side of the cali- per.

The parts forming the caliper may be machined in a relatively simple fashion using standard tools. The caliper of the present invention is formed of a number of separate units that are put together in a simple way. A modular de- sign has many advantages concerning production, handling, service and after-market as well. Calipers not formed in one piece are often referred to as bolted calipers.

The caliper may be attached to the wheel axle in dif- ferent ways giving a flexible mounting. A first example is the relatively normal way that the caliper is attached to a torque support means, such as a torque plate. A second ex- ample is that some part of the caliper is integrated with the wheel axle, e. g. with the hub of the wheel axle or the wheel suspension etc. Thus, a person skilled in the art re- alises that the exact form of the caliper will vary, de- pending inter alia on the connection to the wheel axle, wheel suspension etc.

In production there are great advantages in the pos- sibility to design the caliper of several parts and thus have smaller units. There are casting advantages e. g. in the possibility to use a so-called automatic casting equip- ment giving economical advantages. The machining of smaller parts is advantageously in that it will be easier to reach different surfaces and confined spaces. Smaller parts give less weight per unit compared to a complete cast caliper and leads to a simplified handling in machining, and in as- sembly. Smaller parts give advantages in service and after- market as a defect part or parts may be replaced without affecting the other parts of the caliper. Smaller parts make it possible to decentralise mounting of the different parts giving logistic advantages.

By using a caliper formed of different parts there are advantages in that the caliper is relatively easy to adapt to the space available for a specific vehicle. Thus, it is possible to just modify the part that needs adapta- tion and it is not necessary to amend a complete caliper, which is both cost and time consuming. It is also possible to make the different parts of differing materials and with differing production methods in order to optimise against cost. One or several parts may e. g. be made of aluminium or other low-density metals or alloys to save weight. It is also possible to have parts made of plastic, ceramics etc.

The caliper parts may be cast but they may be produced by any suitable method.

By means of the present invention stability of the : structure in the brake is given by a part of the caliper being an extended part of the mounting means of the brake, which is mounted to the brake torque support means of the axle. By this arrangement stability is given to the brake pads but also the other parts of the brake, which are ex- posed to high loads when the brake is applied. Furthermore, a load absorbing effect is achieved in relation to the brake pads. The structure gives a unified load flow from the back plates holding the brake pads through that part of the caliper that is an extended part of the mounting means of the brake. There will be advantages both relating bend- ing and torsional strength, which also will give an even wear of the brake pads. Still a further advantage is that the mounting means of the brake and the brake torque sup- port means of the axle may be cast as one common part.

The brake mechanism and/or certain elements of it are to be mounted from the front side, often referred to as the disc side. The brake mechanism is, normally mounted as a unit, which unit may be a pre-assembled unit. The brake mechanism may be of many different types. Thus, it may be a traditional mechanism with two tappets or a mechanism hav-

ing one tappet. It could also be certain parts of a mecha- nism for a brake actuated by an electromotor.

The disc brake has one or more brake discs. At least one of the brake discs is normally received floating or sliding in the axial direction. In some embodiments at least one brake disc is received fixed in the axial direc- tion.

Further objects and advantage with the present inven- tion will be obvious for a person skilled in the art when reading the detailed description below of preferred embodi- ments.

Brief Description of the Drawings The invention will be described more closely below by way of examples and with reference to the enclosed draw- ings. In the drawings: Figs. la and lb are a sectional view and side view, respectively of a first embodiment of the present inven- tion, Figs. 2a and 2b are a sectional view and side view, respectively of a second embodiment of the present inven- tion, Figs. 3a and 3b are a sectional view and side view, respectively of a third embodiment of the present inven- tion, Fig. 4 is a sectional view schematically showing one example of attachment for the embodiment of Figs. la and lb to a wheel axle, Fig. 5 is a perspective view showing one example of attachment for a modular caliper according to the present invention, and Fig. 6 is a perspective view showing a further exam- ple of attachment for a modular caliper according to the present invention.

Detailed Description of Preferred Embodiments In Fig. 1 a first embodiment of a modular caliper is shown. The caliper in this example consists of three parts, a central part 1, a front part 2 and a rear part 3. The different parts of the caliper are connected to each other in any suitable form, e. g. by means of screws, bolts, riv- ets, welding. Thus, the different parts 1, 2,3 of the caliper are held together by one or more bolted joints or the like. The central part 1 of the caliper is to be con- nected to the torque support means (not shown) of the vehi- cle, in a relatively normal way known to a person skilled in the art. The torque support means may be a torque plate.

As an alternative the central part 1 of the caliper may be an integrated part of the axle arrangement, e. g. by being formed together with the axle structure of the vehicle. One way to achieve this is to totally integrate the central part 1 of the caliper with the hub of the axle. A person skilled in the art realises that instead of the wheel axle arrangement as such the central part 1 may be integrated with other suitable parts of the vehicle, e. g. the wheel suspension. The rear part 3 of the caliper has a hollow space 9 for receiving at least a part of a brake mechanism.

The brake mechanism is mounted as a unit from the front (disc) side.

In Fig. 2 a second embodiment of the invention is shown. In this embodiment the caliper is divided into two parts, a front part 4 and a rear part 5. The two parts of the caliper are connected to each other by any suitable means, such as screws, bolts, rivets, welds etc. The front part 4 of the caliper is to be connected to the torque sup- port means (not shown) of the vehicle in a normal way. As an alternative the front part 4 of the caliper may be an integrated part of the wheel axle arrangement, the wheel suspension or any other suitable means, in a way indicated above for the previous embodiment. The rear part 5 of the

caliper has a hollow space 11 for receiving at least a part of a brake mechanism.

In the third embodiment of Fig. 3 the caliper is di- vided into two parts, a front part 6 and a rear part 7.

Also in this case the two parts 6, 7 of the caliper are connected to each other in any suitable means, such as by means of screws, bolts, rivets, welding etc. The rear part 7 of the caliper is to be attached to the hub of the wheel axle, the wheel suspension or any other suitable part. Nor- mally the rear part 7 of the caliper is attached to the hub of the wheel axle etc. in a fixed way. In the same way as for the previous embodiments one part, in this case the rear part 7, may be an integrated part of the axle arrange- ment, the wheel suspension etc. The rear part 7 has a hol- low space 13 for at least a part of the brake mechanism.

The part of the caliper to be attached to the torque support means of the vehicle could be said to form a torque support member or extended mounting means. Thus, in the em- bodiment of Fig. 1 the extended mounting means is the cen- tral part 1 of the caliper. In the embodiment of Fig. 2 the extended mounting means is the front part 4 of the caliper.

Finally, in the embodiment of Fig. 3 the extended mounting means is the rear part 7 of the caliper.

In Fig. 4 one example of how the caliper is attached to a wheel axle 14 is indicated. In the shown embodiment the central part 1 of the caliper is attached by means of a weld 15 to the wheel axle 14.

In the embodiment of Fig. 5 a rear part 17 of the caliper is formed integrated with an axle 19 of the vehi- cle. The shown caliper is divided into two parts and the front part 16 is fixed to the rear part 17 by means of a number of bolts 18. A person skilled in the art realises that the rear part 17 and the front part 16 of the caliper may be attached in any suitable way. As the exact form of the brake discs and other parts of the brake is of no im-

portance for the invention they will not be described fur- ther here.

The embodiment of Fig. 6 corresponds to the embodi- ment of Fig. 5 except that the rear part 21 is integrated to a part 23 of a wheel suspension. Said suspension part is a suspension frame for a steerable wheel, e. g. a front wheel of a heavy road vehicle. In the same way as for the embodiment of Fig. 5 the front part 20 is attached to the rear part 21 by means of bolts 22.

According to the present invention the different parts 1,2, 3; 4,5 ; 6,7 ; 16,17 ; 20,21 of the caliper are held together by means of one or more bolted joints or the like.

A person skilled in the art realises that the caliper may be divided in many different ways and the shown embodi- ments are only some examples of possible divisions. Thus, the caliper may be divided into more than three parts. It is also preferred that at least one of the parts of the caliper is an extended mounting means, as indicated above.

As stated above one of the parts of the caliper forms an extended mounting means. This is achieved in that that part 1, 4,7, 17,21 is either fixed to or is integrated with a part of the torque support means of the vehicle or a part of the wheel axle or wheel suspension. By this ar- rangement the brake pads will be given stiffness and a load relief. This also goes for the rest of the brake, which is exposed to high loads at actuation of the brake.

By means of the invention there will be a unified transfer of brake load from the back plates of the brake pads to that part of the caliper that is attached to or in- tegrated with a part of the wheel axle or the wheel suspen- sion means. The result will be that the brake pads are more evenly worn, as both bending and torsional strength will be improved.