Abstract:
In a pump housing, in block form, of a vehicle brake system, having a top side which is manufactured to final dimensions and a bottom side which is manufactured to final dimensions, the final dimensions of the top side and of the bottom side are obtained by means of a non-cutting deformation process starting from a blank.

Description:
[0001]    This application is a divisional application of copending U.S. patent application Ser. No. 13/991,026, filed on Aug. 16, 2013, which is a 35 U.S.C. §371 National Stage Application of PCT/EP2011/067961, filed on Oct. 14, 2011, which claims the benefit of priority to Serial No. DE 10 2010 062 270.2, filed on Dec. 1, 2010 in Germany, the disclosures of which are incorporated herein by reference in their entirety. 
     
    
     BACKGROUND 
       [0002]    The disclosure relates to a block-form pump housing of a vehicle brake system, having a top side manufactured to final dimensions and a bottom side manufactured to final dimensions, and also to a process for producing such a block-form pump housing. 
         [0003]    Block-form pump housings of vehicle brake systems are produced as what are known as hydraulic blocks generally from aluminum. In this case, use is made of a manufacturing process in which firstly crude aluminum is processed to form semifinished rod product. The rods are then sawn into blocks, which are worked to final dimensions on at least one side by means of cutting manufacturing, generally a milling process. Otherwise, the dimensional tolerances which are required for the further processing for the pump housing cannot be produced. 
         [0004]    The disclosure is based on the object of providing a pump housing of a vehicle brake system which can be produced more cost-effectively. 
       SUMMARY 
       [0005]    The invention provides a block-form pump housing of a vehicle brake system and a process for the production thereof, having a top side manufactured to final dimensions and a bottom side manufactured to final dimensions, in which the final dimensions of the top side and of the bottom side have been or are produced by means of a non-cutting forming process from a blank. 
         [0006]    According to the disclosure, the blank of the pump housing is initially sawn in the form of aluminum rods in particular after an extrusion process and then formed without cutting. Forming embraces all manufacturing processes in which metals in particular are changed plastically in a targeted manner to a different shape. Reference is also made to plastic shaping. Here, it is often the case that firstly a primary formed (for example cast) primary material (a strand from continuous casting or an ingot from ingot casting) is formed into a semifinished product or a blank. The mass and the cohesion of the material are retained during the forming, even though the density of the material can change. Forming differs from deforming in that the change in shape is made in a targeted manner. 
         [0007]    The procedure according to the disclosure removes the costs for cutting machining and furthermore also for deburring on at least one side of the pump housing. The surface machined without cutting affords more protection against corrosion, as a result of which costs for sealing the surface can be saved. Alternatively, the protection of the surface can be provided during the production of the blank, because the surface is no longer subjected to cutting. 
         [0008]    The weight of the blank can be reduced, since the oversize of approximately 0.5 mm available for the cutting manufacturing can be dispensed with. This results in a further cost saving in relation to the consumption of raw material. 
         [0009]    It is also the case that identification is no longer required for the individual sides or surfaces of the block-form pump housing, since these are produced with the same quality. Further costs are therefore dropped. A 100% check of the dimensions is also no longer necessary, since these can surprisingly be produced with a particular process reliability by means of non-cutting forming. This applies in particular to the large quantities desired for vehicle brake systems. The procedure according to the disclosure makes it possible to ensure a high stability of the shape and dimensions throughout the production process. 
         [0010]    Finally, there is also no need to provide particular holding surfaces for fastening during cutting machining. Forces which need to be resisted arise in a plurality of axes in the case of such cutting machining. To this end, in production processes to date, a special clamping pocket was provided with an undercut for the second clamping position, in particular, on the pump housing. 
         [0011]    Pressing, in particular pressing with at least one roller or alternatively with at least one ram, is preferably carried out as the non-cutting forming process. 
         [0012]    The blank is preferably produced by means of an extrusion process. 
         [0013]    The final dimensions of the top side and of the bottom side are preferably produced to a tolerance of less than 0.1 mm. The non-cutting forming brings the blank into the block thickness mentioned in the range of 0.5 mm to 0.2 mm, without cutting machining being required. During the cutting of openings in the block-form pump housing following the procedure according to the disclosure, attention then no longer has to be paid to the orientation of the pump housing, because the first and the second clamping positions for these operations for cutting openings are conceptually equivalent. 
         [0014]    After the non-cutting forming process, the pump housing is in particular provided with surface protection. Anodization or an atmospheric protection with plasma is advantageously provided as the surface protection. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]    An exemplary embodiment of the solution according to the disclosure will be explained in more detail hereinbelow with reference to the accompanying schematic drawings, in which: 
           [0016]      FIG. 1  shows a sequence of steps for producing a block-form pump housing according to the prior art, 
           [0017]      FIG. 2  shows a perspective view of a pump housing having a top side manufactured to final dimensions and a bottom side manufactured to final dimensions according to the prior art, before the first cutting of openings, 
           [0018]      FIG. 3  shows a side view of the pump housing as shown in  FIG. 2  in its first clamping apparatus, 
           [0019]      FIG. 4  shows a perspective view of a first clamping arrangement as a whole with first clamping apparatuses as shown in  FIG. 3 , 
           [0020]      FIG. 5  shows a perspective view of a pump housing having a top side manufactured to final dimensions and a bottom side manufactured to final dimensions according to the prior art, before the second cutting of openings, 
           [0021]      FIG. 6  shows a side view of the pump housing as shown in  FIG. 5  in its second clamping apparatus, 
           [0022]      FIG. 7  shows a perspective view of a second clamping arrangement as a whole with second clamping apparatuses as shown in  FIG. 6 , 
           [0023]      FIG. 8  shows a sequence of steps for producing a block-form pump housing according to a first exemplary embodiment of the disclosure, 
           [0024]      FIG. 9  shows a sequence of steps for producing a block-form pump housing according to a second exemplary embodiment of the disclosure, 
           [0025]      FIG. 10  shows a perspective view of a pump housing having a top side manufactured to final dimensions and a bottom side manufactured to final dimensions according to the disclosure, before the first cutting of openings, 
           [0026]      FIG. 11  shows a side view of the pump housing as shown in  FIG. 10  in its first clamping apparatus, 
           [0027]      FIG. 12  shows a perspective view of a first clamping arrangement as a whole with first clamping apparatuses as shown in  FIG. 11 , 
           [0028]      FIG. 13  shows a perspective view of a pump housing having a top side manufactured to final dimensions and a bottom side manufactured to final dimensions according to the disclosure, before the second cutting of openings, 
           [0029]      FIG. 14  shows a side view of the pump housing as shown in  FIG. 13  in its second clamping apparatus, and 
           [0030]      FIG. 15  shows a perspective view of a second clamping arrangement as a whole with second clamping apparatuses as shown in  FIG. 14 . 
       
    
    
     DETAILED DESCRIPTION 
       [0031]      FIG. 1  illustrates individual steps  10  to  22  for producing a block-form pump housing  24  according to the prior art. In step  10 , liquid aluminum  26  is introduced into a chill  28  and rod stock  30  is cast at a temperature of approximately 650° C. The rod stock  30  is annealed in a furnace  32  in step  11 . In step  12 , the rod stock  30  is over-turned and sawn into rod portions  34  with a length of approximately 1500 mm. In step  13 , the individual rod portion  34  is then surveyed with a probe  36  with respect to its calibrated standard defect size. 
         [0032]    In step  14 , six rod portions  34  (only one is shown) are processed in parallel in an extrusion process by means of an extruder  38  at approximately 450° C. at a discharge nozzle  40  to form a strand  42 , which is then cooled to approximately 520° C. at a cooling system  44 . The individual strand  42  here does not have a purely rectangular cross section, but rather is provided on one of its side faces with two web-shaped, longitudinally directed markings  45 . In step  15 , a plurality of such strands  42  are stretched to a length of approximately 20 m at a stretching device  46 , and then the end portions  48  of the stretched strands  42  are sawn off at the ends. 
         [0033]    These steps  10  to  16  are followed by step  17 , in which the prepared strands  42  are annealed in a furnace  50  at a temperature of approximately 175° C. Then, in step  18 , the annealed strands  42  are sawn into individual blocks  54  by means of a saw  52 . Each of these blocks  54  is then processed further to form an individual pump housing  24 . In this case, the block  54  is firstly deburred in step  19 . Then, the individual block  54  is surveyed in steps  20  to  22 , where it is placed against various hard end stops  56  and pressed on by means of a diamond probe  58  and also a plurality of spherical probes  60 . 
         [0034]      FIGS. 2 to 4  illustrate how the thus prepared and surveyed block  54  of a pump housing  24  is provided with openings  62  in a first clamping system. The block  54  is identified in its position by means of the web-shaped markings  45  and is oriented in such a way that it is placed against an end stop  64  with its side face  63  (top side) which lies opposite the markings  45 . In this case, the block  54  is pressed against the end stop  64  by means of such a great force  66  that it can be cut at the side face  63  by means of a tool  68  in order to form one of the openings  62  there. 
         [0035]      FIG. 4  shows, in this respect, the associated clamping apparatus  70 , on which in total twelve blocks  54 , as illustrated individually in  FIG. 3 , are held. 
         [0036]      FIG. 5  shows the thus prepared block  54  with its openings  62 , where one of the openings  62  has been provided with an undercut  72 . At this undercut  72 , this block  54  is pulled against an end stop  76  by means of a holding tool  74 , in order to thus hold it in a second clamping system, as shown in  FIG. 6 . Clamped in this way, the block  54  can be over-milled with a milling cutter  78  on that side face  79  (bottom side) on which the markings  45  were located. Furthermore, further openings  62  can be formed on this side face  79  using tools  68 . 
         [0037]      FIG. 7 , in this respect, again illustrates an associated clamping apparatus  78  for this second clamping system with its total of twelve holding tools  74 . 
         [0038]      FIGS. 8 to 15  illustrate the procedure according to the disclosure. Thus,  FIG. 8  shows a first exemplary embodiment of the step-by-step production of a pump housing  24  according to the disclosure. In this production process, steps  10  to  14  are substantially the same as those in  FIG. 1 , where already in step  14  there is a difference in that the strands  42  are not provided with web-shaped markings  45 , but rather instead have a substantially rectangular cross section  80 . Steps  15  to  17 , too, correspond to those steps in  FIG. 1 . 
         [0039]    Step  17 , which involves the annealing of the prepared strands  42 , is followed in  FIG. 8 , however, by a new step  82 , in which a blank in the form of one strand  42  or a plurality of strands  42  is brought in its thickness to a tolerance  86  of less than 0.1 mm by means of rollers  84  lying opposite one another. This tolerance  86  can be produced so as to be stable throughout the manufacturing process in such a manner that, although step  19  for deburring and steps  20  and  22  still take place in the subsequent process after sawing in step  18 , one of the surveying steps, specifically step  21 , can be dispensed with. It can also be identified in particular in the illustration of step  19  as shown in  FIG. 8  that the block  54  formed to thickness dimensions has no markings  45 , and instead has a rectangular cross section  80  there. 
         [0040]      FIG. 9  illustrates a further exemplary embodiment of the step-by-step production of a pump housing  24  according to the disclosure, in which steps  10  to  17  and  18  to  20  and also  22  correspond to those in  FIG. 8 . In this exemplary embodiment, in step  82 , the strand or strands  42  are not formed to a thickness dimension with a very small tolerance  86  with rollers, but rather with a ram  88  and a counterbearing  90 . 
         [0041]      FIGS. 10 to 12  show how the thus prepared block  54  according to the disclosure is further processed in a first clamping system with a clamping apparatus  70 . This clamping system corresponds substantially to that shown in  FIGS. 3 and 4 , but it should be noted that no web-shaped markings  45  are to be found on the block  54  as shown in  FIG. 10  and also no undercut  72  is to be formed. 
         [0042]      FIGS. 13 to 15  then show the second clamping system for the block  54  according to the disclosure, in which the block  54  no longer needs to be over-milled and there is also no longer a need for an undercut  72  or a holding tool  74  to be able to hold it on the associated clamping apparatus  70 . Instead, as shown in  FIG. 14 , the block  54  can be pressed against an end stop  76  in a conventional manner using a force  66  and machined by means of a tool  68 , in order to form openings  62  therein.