[0001] The present invention relates to an internal combustion engine air supply device.
[0002] As we know, internal combustion engine air supply devices substantially comprise
a throttled body, a torque motor for operating the throttle, and a sensor for detecting
the position of the throttle.
[0003] Air supply devices of the aforementioned type present several drawbacks.
[0004] In particular, the electronics controlling the electric components on the throttled
body are installed in the electronic control system controlling the internal combustion
engine and all the other electric components on the vehicle, so that the control system
is both cumbersome and, hence, difficult to house. Moreover, by virtue of being housed
inside the engine compartment on the vehicle, the electronic control system is also
unfavourably located as regards effective heat exchange. As we know, the engine compartment
is one of the hottest parts of the vehicle, and poses serious problems as regards
heat exchange for dissipating the heat produced by the electronic blocks with which
the control system is provided, and also by the power blocks of the electronics controlling
the electric components on the throttled body. The control system and the electric
components on the throttled body are connected electrically over cables necessarily
extending over a long route. Extensive routing of the electric cables is known to
result in electronic disturbance frequently caused by interference with the electromagnetic
fields produced by nearby electric components, so that the electric cables act as
an antenna for receiving spurious signals. Finally, in view of the length of the path
along which the electric cables are routed, care must be taken to avoid thermal and
mechanical hazards by which the cables might possibly be damaged; and a number of
assembly brackets and anchoring devices are required, thus increasing the complexity
and cost of the electric connections.
[0005] It is an object of the present invention to provide an internal combustion engine
air supply device designed to enable a reduction in the size of the control system,
a reduction in, and hence more effective dissipation of, the heat produced by the
control system, and which provides for solving the problems posed by the electric
connections between the control system and the components on the throttled body.
[0006] Further objects and advantages of the present invention will be disclosed in the
following description.
[0007] According to the present invention, there is provided an internal combustion engine
air supply device comprising a body having a channel for supplying air to said internal
combustion engine; a throttle installed along said channel; drive means for operating
said throttle; and a sensor for detecting the position of said throttle; characterized
by the fact that it presents an electronic device for controlling said drive means
and said sensor; and a seat formed in said body and housing said electronic device.
[0008] A preferred, non-limiting embodiment of the present invention will be described by
way of example with reference to the accompanying drawings, in which:
Fig.1 shows a partially sectioned view of a device in accordance with the teachings
of the present invention;
Fig.2 shows a cross section of the Fig.1 device;
Fig.3 shows a side view of the Fig.1 device.
[0009] Number 1 in the accompanying drawings indicates an air supply device for a vehicle
internal combustion engine (not shown). Device 1 comprises a substantially cylindrical
channel 2 of axis 9, for supplying air to the internal combustion engine; a throttle
3 housed inside channel 2, for choking the air supply; a motor 4 (normally a torque
motor) for operating throttle 3; a sensor 27 for detecting the position of throttle
3; and a printed circuit 6 comprising a number of electric blocks for controlling
motor 4 and sensor 27, and for additional functions described hereinafter. Device
1 also comprises a metal body 7 in which are formed said channel 2; a seat 8 of axis
10, for housing motor 4; a seat 11 also of axis 10, for housing a spring assembly
26 and a limit stop 5 for assembly 26; and a seat 12 for printed circuit 6.
[0010] As shown in the accompanying drawings, body 7 comprises a substantially prismatic
central element 13 having a through hole of axis 9 and defining channel 2; a box element
14 originating from a first outer lateral wall 15 of element 13 and internally defining
seat 8; and a box element 16 extending from a second outer lateral wall 17 of element
13, opposite said first wall 15, and internally defining seat 11. A tubular portion
19, defining the mouth of channel 2, extends outwards of element 13 from lateral wall
18 of element 13 and coaxially with channel 2. Between walls 15 and 17, element 13
presents a lateral wall 21 from which originates a coplanar tab 22; wall 21 and tab
22 defining the end wall of seat 12. Tab 22 extends from the edge defined between
walls 21 and 17, and by a length greater than the longitudinal extension of element
16, so that (Fig.1) the first portion of tab 22 is an integral part of a corresponding
lateral wall of element 16.
[0011] As shown in Fig.2, seat 8 presents a fluidtight cover plate 23 screwed to element
14 by means of screws 24; and motor 4 presents an output shaft 25, of axis 10, extending
from seat 8 to seat 11 and through channel 2. The portion of shaft 25 inside channel
2 is fitted by means of screws 29 with throttle 3; while the portion of shaft 25 inside
seat 11 is fitted with sensor 27, which, in the example embodiment shown, is represented
by an electric potentiometer. Between shaft 25 and an anchorage defined by a portion
of element 16, seat 11 houses spring assembly 26 of known type and operation. Sensor
27 is integrated in the (fluidtight) cover plate of seat 11, and is screwed to element
16 by means of screws 28.
[0012] With reference to Fig.s 1 and 3, seat 12 is defined by an end wall composed of wall
21 and tab 22; by four low lateral walls 31; and by a fluidtight cover plate 32. Printed
circuit 6 is fitted to the end wall of seat 12 by means of screws 33, and presents
a so-called "intelligent" electronic device 34 capable of processing data, controlling
and diagnosing motor 4 and sensor 27, and transmitting and receiving data to/from
an electronic control system 35 controlling the vehicle internal combustion engine,
and to/from a control panel 36 in the passenger compartment of the vehicle. Control
system 35 and panel 36 are shown schematically by respective blocks in Fig.1. Device
34 comprises a number of electronic blocks divided schematically into low-heat-dissipation
blocks 34a producing little heat as a consequence of the Joule effect, and high-heat-dissipation
power blocks 34b producing considerable heat as a consequence of the Joule effect,
and including, for example, the driver of motor 4 and the electric supply stabilizer
of device 34. Blocks 34b are located in a portion 38 of printed circuit 6 close to
a lateral wall portion of channel 2 (as shown in Fig.1), so that the heat produced
by blocks 34b is advantageously dissipated towards the air flowing along channel 2
and which thus also provides for cooling device 1.
[0013] With reference to Fig.s 1 and 3, printed circuit 6 presents a group 41 of electric
connections for connecting circuit 6 to the terminals of the electric winding of motor
4; a group 42 of electric connections for connecting circuit 6 to the terminals of
sensor 27; and a group 43 of electric connections for connecting circuit 6 to a male
connector 44 supported on tab 22. All the above electric connections are welded so
that efficiency is unaffected by vibration of body 7. Male connector 44 is connected
to a female connector 45 (Fig.1) from which originate two bundles 46 of electric cables
respectively connecting control system 35 and panel 36. Bundles 46 are fitted with
an antivibration clamp 51 screwed by means of screw 52 to the plate defined by sensor
27.
[0014] As shown in Fig.1, the block indicating control system 35 contains a block 53 indicating
a data storage circuit, in particular for memorizing the speed of the vehicle; and
the block indicating panel 36 contains four blocks 47, 48, 49, 50 indicating the members
for controlling or enabling the overall function of panel 36, which consists in automatically
controlling the speed of the vehicle. In more detail, block 47 indicates a manually
operated switch for enabling or disabling the automatic vehicle speed control function
of panel 36. Block 48 indicates a manually operated switch for memorizing in block
53 and setting by means of control system 35 a vehicle speed equal to the traveling
speed of the vehicle when block 48 is operated.
[0015] Block 49 indicates a switch operated by means of the brake and/or clutch pedal for
temporarily disabling the automatic control function of panel 36. Block 50 indicates
a switch operated manually between two states for setting a vehicle speed selection
strategy immediately following operation of block 49, normally as a result of braking.
In a first of said two states, vehicle speed is controlled by the user via the accelerator
pedal; while, in the second, the vehicle is restored automatically to the set memorized
speed.
[0016] Device 34 performs various functions, of which only the principal ones will be dealt
with herein.
[0017] These include enabling control of motor 4, and evaluating the response of throttle
3 to motor 4, as indicated by throttle position sensor 27. In this way, it is possible
to determine any positioning errors of throttle 3 due to a defect on motor 4 or to
severe friction along shaft 25. Device 34 also determines the energy consumption of
motor 4, which, if excessive, indicates either a defect on motor 4 or severe friction
along shaft 25. In other words, device 34 provides for locally diagnosing operation
of motor 4 and sensor 27. Another principal function of device 34 consists in evaluating
the consistency, i.e. the correct sequence, of the controls set by blocks 47, 48,
49 and 50, which obviously translates into a diagnosis of the blocks themselves.
[0018] The advantages of the present invention will be clear from the foregoing description.
[0019] Firstly, it provides a solution to the installation problems of electronic control
system 35 inside the engine compartment, both as regards the size of the system, and
the amount of heat produced and the manner in which it is dispersed. According to
the present invention, in fact, control system 35 controlling the internal combustion
engine and all the other electric components on the vehicle is smaller as compared
with currently used systems, by virtue of the electronics controlling the electric
components on throttled body 7 being separated from system 35. From the heating standpoint
also, control system 35 produces less heat as compared with currently used systems;
and, on device 1, the electronic blocks of device 34 producing most heat are concentrated
in a limited area close to the lateral wall of channel 2, thus enabling the air flowing
along channel 2 to be exploited for dissipating the heat produced by device 34. Such
dissipation obviously also provides for advantages as regards the engine, especially
when this is cold- started.
[0020] Secondly, the length of the electric connections between the control blocks of the
throttled body and the electric components on the body itself is minimized, thus minimizing
electronic disturbance caused by interference with the electromagnetic fields produced
by any nearby electric components.
[0021] Thirdly, minimizing the length of the electric connections provides for troublefree
routing of the cables inside the engine compartment; for eliminating the need to so
route the cables as to avoid thermal and mechanical hazards by which the cables might
be damaged; and also for considerably reducing assembly cost by eliminating the assembly
brackets and anchorages.
[0022] Moreover, the functions (control, check, diagnosis, etc.) performable directly on
throttled body 7 by device 34 are unaffected by signal errors caused, for example,
by electrical interference of any type, and as such are more precise and effective.
Also, by virtue of being welded, the electric connections between device 34 and the
electric components connected to it are unaffected by vibration of body 7, thus improving
the efficiency and extending the working life of the connections.
[0023] To those skilled in the art it will be clear that changes may be made to device 1
as described and illustrated herein without, however, departing from the scope of
the present invention.
1. An internal combustion engine air supply device comprising a body (7) having a
channel (2) for supplying air to said internal combustion engine; a throttle (3) installed
along said channel (2); drive means (4) for operating said throttle (3); and a sensor
(27) for detecting the position of said throttle (3); characterized by the fact that
it presents an electronic device (34) for controlling said drive means (4) and said
sensor (27); and a first seat (12) formed in said body (7) and housing said electronic
device (34).
2. A device as claimed in Claim 1, characterized by the fact that said electronic
device comprises a printed circuit (6) in turn comprising a number of electric blocks
(34a, 34b).
3. A device as claimed in Claim 2, characterized by the fact that said electric blocks
are defined by first low-heat-dissipation electric blocks (34a) and by second high-heat-dissipation
blocks (34b); said second blocks (34b) being located on a portion (38) of said printed
circuit (6) close to said channel (2).
4. A device as claimed in Claim 2 or 3, characterized by the fact that said printed
circuit (6) presents a first group (41) of electric connections for connecting said
printed circuit (6) to the terminals of said drive means (4); a second group (42)
of electric connections for connecting said printed circuit (6) to the terminals of
said sensor (27); and a third group (43) of electric connections for connecting said
printed circuit (6) to a male connector (44); said first, second and third groups
(41, 42, 43) of electric connections being welded.
5. A device as claimed in Claim 4, characterized by the fact that said male connector
(44) is connected to a female connector (45) from which originates a first bundle
(46) of electric cables for connection to an electronic control system (35) controlling
said internal combustion engine.
6. A device as claimed in Claim 5, characterized by the fact that, from said female
connector (45), there originates a second bundle (46) of electric cables for connection
to an automatic control panel (36).
7. A device as claimed in at least one of the foregoing Claims, characterized by the
fact that said first seat (12) presents a fluidtight cover plate (32).
8. A device as claimed in at least one of the foregoing Claims, characterized by the
fact that said body (7) comprises said channel 2; said first seat (12); a second seat
(8) housing said drive means (4); and a third seat (11) housing said sensor (27).
9. A device as claimed in Claim 8, characterized by the fact that said body (7) comprises
a substantially prismatic central element (13) having a through hole defining said
channel (2); a first box element (14) originating from a first outer lateral wall
(15) of said central element (13) and internally defining said second seat (8); and
a second box element (16) extending from a second outer lateral wall (17) of said
central element (13), opposite said first wall (15), and internally defining said
third seat (11); between said first and second lateral walls (15, 17), said central
element (13) presenting a third lateral wall (21) from which originates a coplanar
tab (22); said third wall (21) and said tab (22) defining the end wall of said first
seat (12).