[0001] The invention relates to an alternator holder for attaching an alternator to an automobile,
the alternator holder comprising a main alternator support for supporting a main alternator.
[0002] It is known to provide automobiles with two or even more alternators to increase
the power production in those cases, when additional electrical components are provided
in the automobile. These two alternators are mounted separately to a motor of the
automobile. However, it has turned out that existing automobiles with two or even
more alternators do not meet the requirements regarding liability and robustness.
This is a particular problem, if the auxiliary alternator is used to supply electrical
power to a sensitive application, e.g. a jammer system. Automobiles with jammer systems
are used to protect convoys of endangered persons by jamming potential bombs in the
vicinity.
[0003] The invention aims at mitigating prior art problems. The invention solves the problem
by an alternator holder for attaching an alternator to a mobile, the alternator holder
comprising (a) a main alternator support supporting a main alternator and (b) an auxiliary
alternator support for supporting an auxiliary alternator.
[0004] The feature that the auxiliary alternator support is for supporting the auxiliary
alternator means that the auxiliary alternator support is shaped such that the auxiliary
alternator can directly be mounted to the alternator holder, e.g. by fastening means
such as screws.
[0005] It is an advantage of the present invention that the main alternator and the auxiliary
alternator are fixed and cannot move with respect to each other. It is therefore possible
to firmly fix both alternators with respect to a motor pulley of a motor of the automobile.
Even under extreme conditions, a driving belt driving the main alternator and/or the
auxiliary alternator safely links the alternators to the motor. Advantageously, the
alternator holder according to the invention also eases upgrading an automobile from
one alternator to two alternators. No qualified stuff is required. Also, once tested,
the alternator holder according to the present invention may be used without further
testing each upgraded automobile. Thus, the holder according to the present invention
is a means for reproducible fixing two alternators to an engine of an automobile.
[0006] In a preferred embodiment, the main alternator support and the auxiliary alternator
support are arranged, such that the main alternator and the auxiliary alternator are
drivable by means of a joint driving belt. This eases upgrading an automobile with
an auxiliary alternator, as an existing motor pulley of the automobile's motor may
be used for also driving the auxiliary alternator.
[0007] It is preferred that the main alternator is electrically insulated with respect to
the auxiliary alternator or to the alternator holder. For example, an insulating element
is placed between the auxiliary alternator and the alternator holder. This is in particular
advantageous, if the alternator holder is used in an automobile comprising a jammer
system. In this case, the auxiliary alternator may drive the jamming system comprising
a jammer antenna. Thus, the jammer antenna does not interfere with a possible electrical
potential of a chassis of the automobile. Alternatively or in addition, the holder
may comprise an insulating part between an adapter for mounting the holder to the
motor and the support for the auxiliary alternator.
[0008] In a preferred embodiment, the alternator holder is part of an alternator assembly
additionally comprising a main alternator supported by the main alternator support
and an auxiliary alternator supported by the auxiliary alternator support.
[0009] Preferably, the alternator assembly comprises a main battery electrical connected
to the main alternator and an auxiliary battery electrically connected to the auxiliary
alternator. When the main alternator is electrically insulated with respect to the
auxiliary alternator, the auxiliary electrical circuit comprising the auxiliary alternator
and the auxiliary battery has a floating earth with respect to a main electrical circuit
that comprises the main alternator and the main battery.
[0010] It is preferred that the main alternator comprises a main pulley and the auxiliary
alternator comprises an auxiliary pulley, wherein the auxiliary pulley has a smaller
diameter than the main pulley. The auxiliary alternator then has a higher power output
than the main alternator.
[0011] It is preferred that the alternator assembly is part of an automobile, in particular
a car, wherein the main alternator is earthed to a chassis of the automobile and the
auxiliary alternator has a floating earth. If, in a preferred embodiment, the automobile
comprises a jamming system, the auxiliary alternator is preferably used to power the
jamming system. Thus, the jamming system has a floating earth and is independent from
possibly changing electrical potentials of a chassis. It is preferred that the main
alternator is connected with the electrical components of the car, such as igniting
system, steering system, and motor components.
[0012] It is turned out to be advantageous to link the auxiliary alternator to the motor
in such a way that one revolution of the motor corresponds to at least two, in particular
to at least three revolutions of the auxiliary alternator. This yields a high power
output of the auxiliary alternator even for an idling engine.
[0013] An embodiment of the present invention is now described with reference to the drawings,
in which
- Figure 1
- depicts a perspective view of an alternator assembly according to the invention comprising
an alternator holder according to the invention; and
- Figure 2
- is another perspective view of the alternator assembly according to Figure 1.
[0014] Figure 1 shows an alternator holder 10 comprising a main alternator support 12 and
an auxiliary alternator support 14.
[0015] Main alternator 16 electrically contacts alternator holder 10 via screws 20a, 20b
via which main alternator 16 is mechanically fixed to the alternator holder 10. In
contrast, auxiliary alternator 18 is insulated from auxiliary alternator support 14
via electrical insulators, wherein in Figure 1 only electrical insulators 22a, 22b
are shown.
[0016] Main alternator 16 comprises a main pulley 24 having a main pulley diameter D
m for cooperating with a driving belt (not shown). Correspondingly, auxiliary alternator
18 comprises an auxiliary pulley (not shown) that is mounted to a shaft 26. Main pulley
24 and the auxiliary pulley are oriented with respect to each other, such that the
driving belt can drive both, the main alternator 16 and the auxiliary alternator 18
simultaneously.
[0017] When mounted to a motor of an automobile via a fixing part 28, the alternators 16,
18 are only mounted to the alternator holder 10. That is, the alternator holder 10
alone holds the alternator 16, 18 in place.
[0018] The alternator holder 10 may be made from e.g. aluminum, cast aluminum, or steel.
It also serves as a heat bridge for the alternators 16, 18. In the automobile, alternator
holder 10 is arranged, such that an air cooler of the automobile also cools the alternators
16, 18.
[0019] To provide for enough electrical power even at idling speed of the motor of the automobile
it is advantageous to choose a transmission ratio t between the motor and the auxiliary
alternator 18 to be for example t = ¼. Thus, the auxiliary alternator rotates faster
than the motor. One revolution of the motor equals to four revolutions of the auxiliary
alternator 18.
[0020] Auxiliary alternator 18 is connected to an auxiliary battery (not shown) and a jamming
system. As auxiliary alternator 18 is electrically insulated from an electrical circuit
of main alternator 16, main alternator 16 being earthed to a chassis of the automobile,
auxiliary alternator 18 has a floating ground. Thus, the main electric circuit of
main alternator 16 and the auxiliary electric circuit of auxiliary alternator 18 are
completely decoupled and cannot influence each other. An antenna of the jamming system
does not interfere with e.g. the igniting system of the motor.
[0021] It is also possible to use the alternator holder and/or the alternator assembly e.g.
in an ambulance. The alternator holder may be adapted to fit with one type of automobile.
If necessary, the alternator holder has be re-designed for use with a different automobile.
List of reference numbers
[0022]
- 10
- alternator holder
- 12
- main alternator support
- 14
- auxiliary alternator support
- 16
- main alternator
- 18
- auxiliary alternator
- 20
- screw
- 22
- electrical insulator
- 24
- main pulley
- 26
- shaft
- 28
- fixing part
- Dm
- main pulley diameter
1. Alternator holder (10) for attaching an alternator to an automobile, the alternator holder (10) comprising
(a) a main alternator support (12) for supporting a main alternator (16), characterized in
(b) an auxiliary alternator support (14) for supporting an auxiliary alternator (18).
2. Alternator holder (10) according to claim 1, the main alternator support (12) and
the auxiliary alternator support (14) being arranged such that the main alternator
(16) and the auxiliary alternator (18) are drivable by means of a joint driving belt.
3. Alternator holder (10) according to any preceding claim the main alternator (16) being
electrically insulated with respect to the auxiliary alternator (18) or to the alternator
holder (10).
4. Alternator assembly, comprising
(i) an alternator holder (10) according to any preceding claim;
(ii) a main alternator (16) supported by the main alternator support (12); and
(iii) an auxiliary alternator (18) supported by the auxiliary alternator support (14).
5. Alternator assembly according to claim 4, comprising
- a main battery electrically connected to the main alternator (16); and
- an auxiliary battery electrically connected to the auxiliary alternator (18).
6. Alternator assembly according to any of claims 4 to 3,
- the main alternator (16) comprising a main pulley (24);
- the auxiliary alternator (18) comprising a auxiliary pulley;
- the auxiliary pulley having a smaller diameter than the main pulley (24).
7. Automobile, in particular car, comprising an alternator assembly according to any of claims 4
to 6, the main alternator (16) being earthed to a chassis of the automobile and the
auxiliary alternator (18) having a floating earth.
8. Automobile according to claim 7, comprising a motor, the main alternator (16) and
the auxiliary alternator (18) being driven by a joint driving belt.
9. Automobile according to claim 8, the auxiliary alternator (18) being adapted such
that one revolution of the motor corresponds to at least two revolutions of the auxiliary
alternator (18).
10. Automobile according to any of claims 7 to 9, the auxiliary alternator (18) powering
an auxiliary electrical circuit, the auxiliary electrical circuit being connected
to a jamming system.