ABS pump connector

A connector is disclosed for providing power to a pump from a circuit in an ABS braking unit. The electrical connector includes a generally cylindrical housing having first and second ends and a length corresponding to the perpendicular distance between the circuit and the pump. In one embodiment, the first end includes a plurality of pins resiliently mounted therein and electronically connected to the second end. The pins are adapted to resiliently engage a corresponding plurality of pads mounted on the circuit for transmitting power to the second end. In a second embodiment, the second end of the connector also includes a plurality of pins resiliently mounted therein and adapted to engage a corresponding plurality of pads mounted on the pump for receiving power transmitted from the first end.

FIELD OF THE INVENTION 
The present invention relates to an internal pump connector for use in a 
system such as an anti-lock braking system (ABS) on an automobile. More 
particularly, the invention relates to a removable connector for providing 
power to an ABS pump from a circuit of an electronic control unit during 
ABS utilization. 
BACKGROUND OF THE INVENTION 
Modern anti-lock braking system (ABS) control units are constructed to 
minimize weight and space requirements of the unit. Current ABS units 
include three major parts: an electronic control unit; a hydraulic control 
unit; and an ABS pump. Typically, the ABS pump is spaced away from the 
electronic control unit by the hydraulic control unit. In order for the 
electronic control unit to supply power to the ABS pump during system 
activation, the pump must be electrically connected to a circuit within 
the electronic control unit. Past designs have used cables which are 
located exterior of the hydraulic control unit to electrically connect 
between pump and circuit. Electrical connections exterior of the hydraulic 
control unit are subjected to severe environmental conditions which may 
lead to degradation of the electrical connection and system performance. 
These cables may also be inadvertently disconnected due to jarring or 
vibration. Known designs also use electrical connections between the 
circuit and ABS pump which extend perpendicular from the circuit of the 
electronic control unit through an aperture in the hydraulic control unit 
to the pump. These electrical connections internal to the hydraulic 
control unit are fastened or fixed to the printed circuit through a 
soldering process at the time the electronic control unit is manufactured. 
The connection fixed to the circuit of the electronic control unit must 
therefore be adapted to pass through a hydraulic control unit and to 
establish an adequate connection to the ABS pump when the ABS system is 
assembled. 
In current practice, the electronic control unit, the hydraulic control 
unit and the ABS pump are manufactured by different suppliers, and are 
assembled together at another location. Current electronic control unit 
designs require that any fixed electrical connection be soldered to the 
printed circuit of the electronic control unit, after which the fixed 
connection is sealed from the exterior environment. As a result, the pump 
electrical connector is attached to the printed circuit at the time the 
electronic control unit is assembled, before the electronic control unit 
is shipped to a final location for assembly into an ABS unit. Because 
fixed electrical connectors protrude perpendicularly from the electronic 
control unit, shipping precautions dictate the use of extra packaging 
space for shipping electronic control units to assembly points to prevent 
damage to the electronic control unit. Nevertheless, shipping and handling 
damage to the connector extending perpendicularly from the electronic 
control unit housing frequently occurs. Moreover, fixing and sealing the 
pump electrical connector increases the complexity of the electronic 
control unit manufacture process. In particular, the connector first must 
be soldered or otherwise fixed to the printed circuit during manufacture 
of the electronic control unit. Because power requirements of the ABS pump 
are large, the connector must be capable of transmitting the necessary 
power. As a result, the electrical contact between the printed circuit and 
the electrical connector may be relatively large and secure. In 
particular, soldering integrity between the printed circuit and the 
connector becomes very complex as the area of the connection increases, 
requiring increased heat and manufacturing attention in order to achieve a 
robust electrical connection. Also, once the connector is fixedly attached 
to the printed circuit, the attachment must be sealed from external 
environmental conditions. Typically, after the electrical connector is 
attached to the printed circuit, a seal is molded in place about the 
electrical connector which forms a seal between the connector and the 
housing of the electronic control unit. Molding this seal requires an 
additional manufacturing step, the integrity of which must be monitored 
closely to prevent unit failure during service lifetime. 
Current designs of electrical connectors between ABS pump and electronic 
control units also limit serviceability of the ABS unit. Because the 
electrical connection is soldered to a printed circuit and then molded in 
place, the electrical connector is not a replaceable part. Should the 
electrical connection ever fail, due to environmental conditions or 
manufacturing defects, the entire electronic control unit would have to be 
replaced rather than simply replacing the electrical connector. 
SUMMARY OF THE INVENTION 
The present invention is directed to an anti-lock braking system of the 
type having an electronic control unit with a printed circuit which 
provides power to a pump, where the pump is separated from the electronic 
control unit by a hydraulic control unit. A connector is disclosed for 
providing power to the pump from the printed circuit. The electrical 
connector includes a generally cylindrical housing having first and second 
ends and a length corresponding to the perpendicular distance between the 
printed circuit and the pump. In one embodiment, the first end includes a 
plurality of pins resiliently mounted in the first end and electronically 
connected to the second end. The pins are adapted to resiliently engage a 
corresponding plurality of contact pads mounted on the printed circuit for 
transmitting power to the second end. In a second embodiment, the second 
end of the connector also includes a plurality of pins resiliently mounted 
in the second end and adapted to engage a corresponding plurality of 
contact pads mounted on the pump for receiving power transmitted from the 
first end. 
The removable connector of the present invention overcomes disadvantages of 
conventional ABS pump electrical connections. The electronic control unit 
need not be fabricated with a permanently attached connector for the pump 
soldered to the printed circuit. As a result, packaging space for shipping 
is minimized, as is the possibility for damage during shipping and 
handling to the connector extension. The electrical connector seal may be 
built into the generally cylindrical housing of connector of the present 
invention, thereby removing a molding and sealing step from the 
manufacture of the electronic control unit. The present inventive 
connector is also not soldered to the printed circuit of the electronic 
control unit, removing the possibility for poor electrical connection or 
failure of the electrical connection to the printed circuit due to 
environmental conditions or shock damage to the connector during shipping 
or installation. Serviceability of the electronic control unit is also 
enhanced through the use of a detachable or removable internal connector 
to the pump.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT 
FIG. 1 displays a prior art electronically controlled hydraulic unit 10 
which is intended for use in an automobile anti-lock braking system (ABS). 
As seen in FIG. 1, pump 12 is attached to hydraulic control unit 14, which 
is shown partially removed from electronic control unit 16. Hydraulic 
control unit 14 includes a plurality of valve actuators 18 which are 
adapted to be received within solenoid coils 20 of electronic control unit 
16. Bosses 22 utilize conventional fastening members to attach the 
hydraulic assembly 10 into position on a host vehicle. An input/output 
connector 24 is located on the exterior of the electronic control unit 16 
to provide for the input and output of both electrical power and signal 
currents to unit 10. A second electrical connector 26 extending generally 
perpendicularly from electronic control unit 16 forms a connection between 
electronic control unit 16 and pump 12 through aperture 28 in hydraulic 
control unit 14 to deliver power to the hydraulic pump 12. 
The prior art assembly of connector 26 is further illustrated with 
reference to FIG. 2. Typically a printed or etched circuit 30 is mounted 
beneath solenoid coils 20 (not shown) within electronic control unit 16. 
Coils 20 are connected to printed circuit 30 to provide an electrical 
current to coils 20 which in turn induces a valve located with an actuator 
18 to move between a seated and an unseated position. Printed circuit 30 
is strengthened by being attached to a composite resin backing 38. The 
strength of printed circuit 30 is further enhanced through the addition of 
an aluminum backing plate 32, which also acts to dissipate waste heat. 
Prior art connector 26 includes at least one blade style terminal 34, and 
is long enough to reach from printed circuit 30 to the underside of pump 
12. A first end 40 of blade style terminal 34 is attached directly to 
circuit 30, usually with solder 36. Prior to attaching first end 40 to 
printed circuit 30, a hole is drilled in both aluminum plate 32 and 
composite resin backing 38 to clear the way for first end 40 to be in 
contact with a solder pad (not shown) on printed circuit 30. Because of 
the size of first end 40 and of the heat capacity of terminals 34 in 
general, it is difficult to achieve a high integrity solder 36 because of 
the heat requirements necessary to heat both first end 40 and printed 
circuit 30 to a requisite temperature such that solder 36 adheres to 
circuit 30. After first end 40 is soldered to printed circuit 30, a seal 
42 is injection molded about terminals 34 to prevent external 
environmental conditions from impacting or affecting the performance of 
circuit 30 and connector 26. Moreover, care must be taken with molded seal 
42 at neck 43 of electronic control unit 16 where connector 26 emerges 
from the top of electronic control unit 16. If molded seal 42 does not 
completely seal at neck 43, then circuit 30 may be exposed to 
environmental elements which may lead to premature degradation of solder 
36 at circuit 30. After seal 42 is molded about terminals 34, connector 26 
is fixed in position and perpendicularly projects a distance above the top 
of electronic control unit 16 generally equal to the thickness of 
hydraulic control unit 14. There is thus potential for damage to connector 
26 when shipping the finished electronic control unit 16 to an assembly 
location where it is assembled to hydraulic control unit 14 and a pump 12. 
To address the shortcomings of the prior art, a first embodiment of the 
present invention is illustrated with reference to FIG. 3. In FIG. 3, a 
hydraulic control unit 14 is shown adjacent to an electronic control unit 
16 in an assembled position. An aperture 28 passes through hydraulic 
control unit 14. A connector 44 passes through aperture 28 and makes 
contact with a printed circuit 30 via contact pads 46 which are mounted 
upon composite resin backing 38 and communicate with etched or printed 
circuit 30. In the first embodiment, a first end 48 of connector 44 
includes a plurality of resilient pins 50. Pins 50 are resiliently mounted 
in the first end 48, and are electrically connected 52 to a second end 54 
of connector 44. Second end 54 includes blade style terminals 56 which are 
adapted to connect to a corresponding connector on the bottom of an 
associated pump (not shown). Resilient pins 50, electrical connection 52 
and blade style terminals 56 are all encased within a generally 
cylindrical connector housing 58 which is sized to provide a seal between 
printed circuit 30 and aperture 28. Furthermore, an O-Ring 60 is located 
adjacent second end 54 to further improve the seal between aperture 28 and 
printed circuit 30. 
Contact between first end 48 of connector 44 and contact pads 46 is further 
described with reference to FIG. 5. As described previously, a circuit 30 
is mounted upon a composite resin backing 38. A first plurality of contact 
pads 46 are also mounted to composite resin backing 38 and are in 
electrical communication with etched or printed circuit 30. A 
corresponding first plurality of resilient pins 50 are mounted within 
generally cylindrical housing connector housing 58 and engage contact pads 
46 to provide an electrical connection there between. Each pin 50 is also 
in electrical communication with terminals 56 on second end 54 (not 
shown). As seen in FIG. 6, pins 50 are resiliently biased to a position 
slightly extending from axial end 62 of first end 48 of connector 44. But 
when pins 50 make contact with pads 46, contact pressure between pins and 
pads 46 is absorbed by pins 50 being forced axially into cylindrical 
housing 58. In an uncompressed configuration, shown in FIG. 6, pins 50 are 
designed to protrude above axial end 62 a predetermined amount, 
approximately 0.25 millimeters per side. By operating resilient pins 50 as 
plungers, a better button contact with pads 46 is achieved, resulting in 
better electrical connection there between. 
Advantages of the resilient nature of pins 50 can be seen in FIG. 7. 
Connector 44 need not be arranged exactly perpendicular to circuit 30 when 
inserted into aperture 28. Because pins 50 are resilient, some angle of 
contact may occur while pins 50 still make contact with pads 46. Thus, 
even if circuit 30 vibrates or if electronic control unit 15 is not 
tightly attached to a hydraulic control unit, pins 50 will continue to 
make contact with pads 46, preventing the ABS unit from becoming 
inoperable under some situations. The resiliency of pins 50 is caused by 
randomly formed wire 74 behind pins 50 which supports pins 50 within 
cylindrical housing 58, as shown in FIG. 8. The randomness of the wire 
formation gives button 50 desirable resiliency, while at the same time 
allowing electronic connection to second end 54 of connector 44. 
Returning to FIG. 4, a second embodiment of a connector 64 is shown in an 
exploded view. Connector 64 includes a plurality of resilient pins 50 
located at both first end 66 and second end 68. Connector 64 is designed 
to fit snugly within aperture 28 through hydraulic control unit 14 and 
extend through electronic control unit 16 down to pads 46 mounted on 
printed circuit 30. In order to align pins 50 with pads 46, cylindrical 
housing 76 may be formed with external keys 78 which are received within 
slots in aperture 28 (not shown). Keys 78 align connector 64 such that all 
pins 50 will contact a corresponding pad 46. Connector 64 thereby provides 
an electrical connection 52 between first end 66 and second end 68, while 
providing a removable connection between circuit 30 and pump 12 (not 
shown). An O-Ring 70 is located intermediate first end 66 and second end 
68 to improve sealing characteristics of generally cylindrical housing 72 
of connector 64. 
The connector of the present invention presents several advantages over 
known methods of transmitting power from a circuit to a pump in an ABS 
unit. Because the connector is removable, the electronic control unit 
portion of the ABS unit need not be fabricated with a permanently attached 
connector for the pump soldered to the circuit. With no permanent 
connector protruding from the electronic control unit, packaging space for 
shipping is minimized, as is the possibility for damage to the connector 
extension during shipping and handling. The electronic circuits of the 
electronic control unit are protected because a seal may be built into the 
generally cylindrical housing of connector of the present invention. 
Addition of a seal to the generally cylindrical housing of the connector 
also removes a molding and sealing step from the manufacture of the 
electronic control unit. 
The present inventive connector is also not soldered to printed circuit of 
the electronic control unit, removing the possibility for poor electrical 
connection or failure of the electrical connection to the printed circuit 
due to environmental conditions or shock damage to the connector during 
shipping or installation. Serviceability of the electronic control unit is 
also enhanced through the use of a detachable or removable internal 
connector to the pump. 
Preferred embodiments of the present invention have been disclosed. A 
person of ordinary skill in the art would realize, however, that certain 
modifications would come within the teachings of this invention. 
Therefore, the following claims should be studied to determine the true 
scope and content of the invention.