Title of Invention

A CONTACT PROTECTION HOUSING, A FUEL DISTRIBUTOR INJECTION PUMP AND A METHOD OF MOUNTING A CONTACT PROTECTION HOUSING WITH THE AID OF AN ADAPTER

Abstract The invention relates to contact protection housing for at least one electrical connection which is arranged in a housing part (7) which is built onto a component (1) and in which an opening (8) is provided for filling with casting compound. The invention also relates to a fuel distributor injection pump, with a previously descried contact protection housing, and to a method of mounting a contact protection housing with an adapter. To reduce the mounting effort, the housing part is formed by a thin-walled cap (7), the edge of which bears uniformly under prestress against the component(1).
Full Text

Contact protection housing, injection pump and method of mounting a contact protection housing with the aid
of an adapter
Prior art
The invention relates to a contact protection housing for at least one electrical connection which is arranged in a housing part which is built onto a component and in which an opening is provided for filling with casting compound. The invention also relates to an injection pump with a contact protection housing, Furthermore, the invention relates to a method of mounting a contact protection housing with the aid of an adapter.
DE 197 03 686 discloses a contact protection housing which comprises two housing parts fitted together. A seal is arranged between the two housing parts. The seal serves the purpose of keeping back not yet solidified casting compound during filling. The seal must be positioned exactly when the contact protection housing is being fitted together. Furthermore, the seal is susceptible to wear.
One object of the invention is to provide a contact protection housing which is formed from fewer individual parts than conventional contact protection housings. In addition, the mounting effort is to be reduced,
The object is achieved in the case of a contact protection housing for at least one electrical connection which is arranged in a housing part which is built onto a component and in which an opening is provided for filling with casting compound by the housing part being formed by a thin-walled cap, the edge of which bears uniformly under prestress against the component.

Advantages of the invention
This provides the advantage that the seal required in the case of conventional contact protection housings can be omitted.
One particular embodiment of the contact protection housing according to the invention is characterized in that the cap has the form of a cylinder which is open at one end face and on the lateral surface of which there is provided a lug which tapers to a point and the flanks of which are of a slightly concave form. The concave form has the effect that the flanks of the cap adapt flexibly to the component. This makes it possible to compensate for production-related tolerances of the component. The venting of the cavity during casting takes place automatically via the remaining slight gap between the line holder and the solenoid valve,
In the case of an injection pump, in particular a distributor injection pump, for motor vehicles, on which a solenoid valve is fastened with the aid of a hollow tensioning screw, the object specified above is achieved by a previously described contact protection housing, the lug of which protrudes beyond the circumference or inside diameter of the hollow tensioning screw. As a result, undesired detachment of the solenoid valve is reliably prevented in the mounted state.
When the cap according to the invention is used, quality problems in the region of the sprue arise when there are high filling nozzle temperatures. Therefore, a further object of the invention is to specify a quick mounting method in which damage to the casting compound is prevented even at high filling nozzle temperatures.

The object is achieved in the case of a method of mounting a previously described contact protection housing on a component, in particular on a previously described injection pump filling with the casting compound being performed with the aid of a nozzle, by an adapter being arranged between the cap and the nozzle during filling with the casting compound. The adapter part separates the nozzle from the cavity. The distance between the cap and the nozzle enforced by the adapter part prevents thermal decomposition of the casting compound in the region of the filling opening in the cap.
An adapter for using the previously described method is characterized in that the adapter has a through-bore with a first portion, the diameter of which is greater than the diameter of the opening in the cap for filling with the casting compound, and with a conical second portion, which tapers from the inside outwards. The first portion serves the purpose of compensating for inaccuracies when the nozzle is being placed against the cap. As a result, satisfactory filling of the cap is ensured even when the nozzle opening is not arranged exactly concentrically in relation to the cap opening, The moulding compound remaining outside the cap in the region of the cap opening after the filling operation forms a knob which is integral with the moulding compound inside the cap. The knob has a greater diameter than the opening in the cap and, as a result, prevents loosening and unwanted removal of the cap after mounting. The conical second portion of the adapter serves for sealing off and centring the filling nozzle.
One particular embodiment of the adapter according to the invention is characterized in that the first portion tapers from the inside outwards. As a result, good demouldability is ensured after the cap has been filled with the casting compound.

A further embodiment of the adapter according to the invention is characterized in that a cylindrical third portion is arranged between the first portion and the second portion. The connection may also be conical, with tapering in the direction of the nozzle, and/or profiled. The third portion allows the casting compound to pass through during filling. The length of the third portion allows the distance between the nozzle and the cap to be varied. The size of the distance between the nozzle and the cap depends, inter alia, on the temperature of the nozzle during filling.
Further advantages, features and details of the invention emerge from the following description, in which an exemplary embodiment of the invention is described in detail with reference to the drawing - The features mentioned in the claims and in the description may be essential for the invention each on their own or in any desired combination.
Drawing
In the drawing:
Figure 1 shows the view of a section through a contact protection housing according to the invention in the empty state;
Figure 2 shows the contact protection housing from Figure 1 in the filled state;
Figure 3 shows the view of a section along the line III-III in Figure 1; and
Figure 4 shows an enlarged detail of the contact protection housing represented in Figure 3.

Description of the exemplary embodiments
Shown in Figure 1 is a solenoid valve 1, which is mounted with the aid of a hollow tensioning screw (not represented) on a distributor injection pump (likewise not represented). Attached to the solenoid valve 1 is a line holder 2, The line holder 2 comprises a fixing aid 3 with an essentially triangular outer contour, The line holder 2 and the fixing aid 3 serve for receiving electrical lines 4. In this case, the electrical lines 4 are arranged in the line holder 2 in such a way that they are positioned at as small a distance as possible from the contact tabs 5 which extend from the solenoid valve 1. The line holder 1 is fastened on the solenoid valve 1 with the aid of a screw 6,
The connection points of the solenoid valve 1 are surrounded by a cap 1, in which an opening 8 is provided. The opening 8 in the cap 7 serves for the filling of the hollow interior space 9 of the cap 1, which is also referred to as the cavity, with a casting compound.
In Figure 2, the cavity 9 is filled with casting compound, Filling with the casting compound takes place through a nozzle 10, An adapter is arranged between the nozzle 10 and the cap 7 of the contact protection housing according to the invention. The adapter 14 has the effect of thermally isolating the cap 7 from the nozzle 10.
The adapter 14 has a central through-bore with a first portion 11, a second portion 12 and a third portion 13. The third portion 13 has the form of a circular cylinder and is arranged between the first portion 11 and the second portion 12 • The connection may also be conical, with tapering in the direction of the nozzle, and/or profiled. During filling with the casting

compound, the third portion 13 forms a spire 16, which is removed after mounting.
The second portion 12 is conically designed and serves
for receiving the tip of the nozzle 10, The first
portion 11 of the through-bore in the adapter 14 is
likewise conically designed. The two cones in the
portions 11 and 12 of the adapter 14 both taper to the
central portion 13, which has the smallest diameter of
the three portions.
In the interior of the first portion 11, the casting compound forms a knob 15. The knob 15 has an outside diameter which is greater than the inside diameter of the bore 8 in the cap 7.
Figure 3 reveals that the cap 7 has a cylindrical outer contour 20, on which there is formed a triangular lug, the flanks of which are denoted by 21 and 22. The tip
of the lug is flattened off.
In Figure 4, the region of the flank 21 of the cap 7 from Figure 3 is represented on an enlarged scale. In the installed state, the flank 21 of the cap 7 bears against the housing of the solenoid valve 1. It is indicated at 23 that, in the non-installed state, the flank 21 of the cap 7 is of a slightly concave form, i.e. curved inwards.
To provide a high-pressure seal, the solenoid valve 1 must be fastened on the distributor injection pump with the aid of the concentrically arranged hollow tensioning screw with a high tightening torque. There would in this case be a very high risk of the trailing length of cable on the solenoid valve 1 being damaged. The solenoid valve 1 therefore merely has two projecting contact tabs 5 for contact to be made later. Owing to the high requirements in operation, the contacting must be permanent. It must be adequately

protected against mechanical loading and media. It must be possible for all the contacting operations to be performed in a predetermined short mounting procedure. All these requirements are satisfied by the invention. The mounting of the contact protection housing according to the invention proceeds as follows.
Firstly, the solenoid valve 1 is screwed onto the distributor injection pump (not represented). Then, the line holder 2 with the electrical lines 4 is fitted onto the exposed end face of the solenoid valve 1. In the process, the two contact tabs 5 of the solenoid valve 1 are led through corresponding openings into the line holder 2, The ends of the stranded wires of the electrical lines 4 are thereby arranged and fixed in such a way that they always lie at a small distance from the contact tabs 5.
After that, the line holder 2 is screwed to the solenoid valve 1 with the aid of the screw 6. Subsequently, the contacting between the ends of the stranded wires of the electrical lines 4 and the contact tabs 5 is established by resistance welding. Soldering or other welding methods are also possible.
In a next step, the covering cap 7 is pressed onto the solenoid valve 1 and the line holder 2, until its bottom comes to bear against the line holder 2. The covering cap 7 is designed in such a way that the edge of the cap bears uniformly with prestress against the solenoid valve 1 and against the hump-shaped fixing aid 3, This achieves sealing off during the following introduction of the casting compound, without an additional sealing element.
The cavity 9 inside the cap 7 is filled with casting compound. Hot-meIt adhesive introduced under positive pressure is used as the casting compound. Hot-meIt adhesive provides the advantage that no additional

introduction of heat or long reaction time at room temperature is required. However, other casting compounds may also be used within the scope of the present invention .
During filling with the casting compound, the cap 7 is held down by the adapter 14, In the region of the spire, a visible formation 15 is retained, also referred to as a knob, The knob creates an interlocking engagement for the axial fixing of the cap 7 to support the frictional engagement after pressing on, The adhesive bonding of the casting compound on the cap 7 has the effect of additionally holding the latter and damping vibrations. Further task [sic] of the casting compound are securing the fastening screw 6 of the line holder 2, providing insulation, of the contacts with respect one another and with respect to earth, protection of the contacts against media and the filling of small voids and undercuts to avoid a suction effect *
The solution according to the invention allows both the advantages of mounting the solenoid valve 1 onto the pump without a trailing length of cable and the known high functional reliability of contacting by means of a trailing length of cable to be used in operation. The construction according to the invention can be used on small subassemblies and on complete products. The required mounting operations can be integrated into line assembly involving short procedures.
The tensioning screw (not represented) of the solenoid valve 1 is captured under the covering cap 7, since the covering cap 7 has radially greater dimensions than the solenoid valve 1, Removal of the covering cap 7 is possible only with accompanying mechanical damage,





Claims
1, Contact protection housing for at least one electrical connection which is arranged in a housing part (7) which is built onto a component (1) and in which an opening (8) is provided for filling with casting compound, characterized in that the housing part is formed by a thin-walled cap (7) the edge of which bears uniformly under prestress against the component (1).
2, Contact protection housing according to Claim 1, characterized in that the cap (7) has the form of a cylinder (20) which is open at one end face and on the lateral surface of which there is provided a lug which tapers to a point and the flanks (21, 22) of which are of a slightly concave form.
3, Fuel injection pump, in particular a distributor injection pump, for motor vehicles, on which a solenoid valve (1) is fastened with the aid of a hollow tensioning screw, characterized by a contact protection housing according to Claim 2, the lug of which protrudes beyond the inside diameter of the hollow tensioning screw.
4, Method of mounting a contact protection housing according to Claim 1 or 2 on a component, in particular on an injection pump according to Claim 3, filling with the casting compound being performed with the aid of a nozzle (10) , characterized in that an adapter (14) is arranged between the cap (7) and the nozzle (10) during filling with the casting compound,
5 - Adapter for using the method according to Claim 4, characterized in that the adapter (14) has a through-bore with a first portion (11), the diameter of which is greater than the diameter of

the opening (8) in the cap (7) for filling with the casting compound, and with a conical second portion (12), which tapers from the inside outwards.
6, Adapter according to Claim 5, characterized in that the first portion (11) tapers from the inside outwards -
7, Adapter according to Claim 5 or 6, characterized in that a cylindrical third portion (13) is arranged between the first portion (11) and the second portion (12) .

8. Contact protection housing substantially as
hereinbefore described with reference to the accompanying
drawings.
9. Fuel injection pump substantially as hereinbefore described
with reference to the accompanying drawings.
10. Method of mounting a contact protection housing
substantially as hereinbefore described with reference to the
accompanying drawings.
11. Adapter for using the method substantially as hereinbefore
described with reference to the accompanying drawings.


Documents:

abs-in-pct-2001-1161-che.jpg

in-pct-2001-1161-che-abstract.pdf

in-pct-2001-1161-che-claims filed.pdf

in-pct-2001-1161-che-claims granted.pdf

in-pct-2001-1161-che-correspondnece-others.pdf

in-pct-2001-1161-che-correspondnece-po.pdf

in-pct-2001-1161-che-description(complete)filed.pdf

in-pct-2001-1161-che-description(complete)granted.pdf

in-pct-2001-1161-che-drawings.pdf

in-pct-2001-1161-che-form 1.pdf

in-pct-2001-1161-che-form 26.pdf

in-pct-2001-1161-che-form 3.pdf

in-pct-2001-1161-che-form 5.pdf

in-pct-2001-1161-che-other documents.pdf

in-pct-2001-1161-che-pct.pdf


Patent Number 212765
Indian Patent Application Number IN/PCT/2001/1161/CHE
PG Journal Number 07/2008
Publication Date 15-Feb-2008
Grant Date 14-Dec-2007
Date of Filing 17-Aug-2001
Name of Patentee ROBERT BOSCH GMBH
Applicant Address Postfach 30 02 20 70442 Stuttgart,
Inventors:
# Inventor's Name Inventor's Address
1 NIESLONY, Markus. Schulstrasse 12/1 73084 Aslach
PCT International Classification Number H01R 13/40
PCT International Application Number PCT/DE00/04099
PCT International Filing date 2000-11-21
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 199 63 933.7 1999-12-31 Germany