Pump Housing, in Block Form, of a Vehicle Brake System, and Method for Producing the Same

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

PRIOR ART

The invention 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.

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.

The invention is based on the object of providing a pump housing of a vehicle brake system which can be produced more cost-effectively.

DISCLOSURE OF THE INVENTION

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.

According to the invention, 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.

The procedure according to the invention 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.

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.

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 invention makes it possible to ensure a high stability of the shape and dimensions throughout the production process.

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.

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.

The blank is preferably produced by means of an extrusion process.

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 invention, 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.

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.

An exemplary embodiment of the solution according to the invention will be explained in more detail hereinbelow with reference to the accompanying schematic drawings, in which:

FIG. 1 shows a sequence of steps for producing a block-form pump housing according to the prior art,

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,

FIG. 3 shows a side view of the pump housing as shown in FIG. 2 in its first clamping apparatus,

FIG. 4 shows a perspective view of a first clamping arrangement as a whole with first clamping apparatuses as shown in FIG. 3,

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,

FIG. 6 shows a side view of the pump housing as shown in FIG. 5 in its second clamping apparatus,

FIG. 7 shows a perspective view of a second clamping arrangement as a whole with second clamping apparatuses as shown in FIG. 6,

FIG. 8 shows a sequence of steps for producing a block-form pump housing according to a first exemplary embodiment of the invention,

FIG. 9 shows a sequence of steps for producing a block-form pump housing according to a second exemplary embodiment of the invention,

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 invention, before the first cutting of openings,

FIG. 11 shows a side view of the pump housing as shown in FIG. 10 in its first clamping apparatus,

FIG. 12 shows a perspective view of a first clamping arrangement as a whole with first clamping apparatuses as shown in FIG. 11,

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 invention, before the second cutting of openings,

FIG. 14 shows a side view of the pump housing as shown in FIG. 13 in its second clamping apparatus, and

FIG. 15 shows a perspective view of a second clamping arrangement as a whole with second clamping apparatuses as shown in FIG. 14.

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.

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.

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.

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.

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.

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.

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.

FIGS. 8 to 15 illustrate the procedure according to the invention. Thus, FIG. 8 shows a first exemplary embodiment of the step-by-step production of a pump housing 24 according to the invention. 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.

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.

FIG. 9 illustrates a further exemplary embodiment of the step-by-step production of a pump housing 24 according to the invention, 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.

FIGS. 10 to 12 show how the thus prepared block 54 according to the invention 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.

FIGS. 13 to 15 then show the second clamping system for the block 54 according to the invention, 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.

Claims

1. A block-form pump housing of a vehicle brake system, comprising: a top side configured to possess first dimensions and a bottom side configured to possess second dimensions, inwherein the top side and of the bottom side are produced from a blank by a non-cutting forming process.

2. The block-form pump housing as claimed in claim 1, wherein the top side and the bottom side are produced from the blank by pressing with rollers.

3. The block-form pump housing as claimed in claim 1, wherein the blank is produced by an extrusion process.

4. The block-form pump housing as claimed in claim 1, wherein the top side and the bottom side each have a dimensional tolerance of less than 0.1 mm.

5. The block-form pump housing as claimed in claim 1, further comprising: a surface protection applied to the block-form pump housing after the non-cutting forming process.

6. A process for producing a block-form pump housing of a vehicle brake system, comprising: manufacturing a top side of the block-form pump housing to first dimensions from a blank by a non-cutting forming processmanufacturing a bottom side of the block-form pump housing to second dimensions from the blank by the non-cutting forming process.

7. The process as claimed in claim 6, further comprising: pressing the blank with rollers to manufacture the top side to the first dimensions and the bottom side to the second dimensions.

8. The process as claimed in claim 6, further comprising: producing the blank using an extrusion process.

9. The process as claimed in claim 6 , further comprising: producing the first dimensions of the top side and the second dimensions of the bottom side to a tolerance of less than 0.1 mm.

10. The process as claimed in claim 6, further comprising: applying a surface protection to the block-form pump housing after the non-cutting forming process.