U.S. patent application number 14/614863 was filed with the patent office on 2015-06-04 for electronic control unit.
The applicant listed for this patent is Hitachi Automotive Systems, Ltd.. Invention is credited to Susumu KANEKO, Kazuaki NAGASHIMA, Ryota TAKAGI.
Application Number | 20150156929 14/614863 |
Document ID | / |
Family ID | 47554292 |
Filed Date | 2015-06-04 |
United States Patent
Application |
20150156929 |
Kind Code |
A1 |
NAGASHIMA; Kazuaki ; et
al. |
June 4, 2015 |
Electronic Control Unit
Abstract
An electronic control unit includes a metallic control block in
which a plurality of control equipments are installed, a metallic
cover member, and an electronic control mechanism. The metallic
cover member is fitted onto the metallic control block. The
electronic control mechanism is retained between the metallic
control block and the metallic cover member to drive the control
equipments. An electrically conducting section is constituted by an
electrically connecting member which electrically conducts the
metallic cover member to the metallic control block via a bus bar
constituent.
Inventors: |
NAGASHIMA; Kazuaki;
(Kiryu-shi, JP) ; TAKAGI; Ryota; (Isesaki-shi,
JP) ; KANEKO; Susumu; (Isesaki-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Hitachi Automotive Systems, Ltd. |
Hitachinaka-shi |
|
JP |
|
|
Family ID: |
47554292 |
Appl. No.: |
14/614863 |
Filed: |
February 5, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13446086 |
Apr 13, 2012 |
|
|
|
14614863 |
|
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|
Current U.S.
Class: |
361/752 |
Current CPC
Class: |
H05K 9/0015 20130101;
H01R 4/48 20130101; B60T 7/042 20130101; H05K 5/0065 20130101; H05K
9/0064 20130101; B60T 8/3675 20130101; H05K 5/04 20130101 |
International
Class: |
H05K 9/00 20060101
H05K009/00; H05K 5/00 20060101 H05K005/00; H05K 5/04 20060101
H05K005/04 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 4, 2011 |
JP |
2011-170613 |
Aug 4, 2011 |
JP |
2011-170614 |
Claims
1. An electronic control unit, comprising: a metallic control block
in which a plurality of control equipments are installed; a
metallic cover member fitted onto the metallic control block; and
an electronic control mechanism retained between the metallic
control block and the metallic cover member to drive the control
equipments, the electronic control mechanism including: a bus bar
constituent made of a resin material and having a power electronic
circuit to drive the control equipments; and a print board to
control the drive of the control equipments via the bus bar
constituent, the print board on which a plurality of electronic
parts are mounted being fixed onto the bus bar constituent by means
of a metallic fixture section and an electrically conducting
section being disposed to electrically conduct the metallic control
block to the metallic cover member to provide the same electric
potential for both of the metallic cover member and the metallic
control block, wherein the electrically conducting section is
constituted by an electrically connecting member which electrically
conducts the metallic cover member to the metallic control block
via the bus bar constituent.
2. The electronic control unit as claimed in claim 1, wherein the
electrically connecting member is an earth connecting member
extended between the metallic control block and the cover member,
the earth connecting member including an elastic deformation
section whose length between both ends of the elastic deformation
section is changeable and which is located on at least either one
of both ends of the earth connecting member in an elongated
direction of the earth connection member.
3. The electronic control unit as claimed in claim 1, wherein a
penetrating hole through which the earth connecting member is
penetrated is formed on the bus bar constituent and retaining
sections which are elastically retained on a hole edge of the
penetrating hole are disposed on a predetermined position of the
earth connecting member in the elongated direction of the earth
connecting member.
4. The electronic control unit as claimed in claim 2, wherein the
earth connecting member is formed in a rectangular plate shape and
the elastic deformation section of the earth connecting member is
bent to form a curve.
5. The electronic control unit as claimed in claim 3, wherein the
retaining sections comprise: a plate-formed base section formed at
a center of the earth connecting member; and a pair of retaining
pieces disposed in parallel to each other at both sides of the base
section and which are elastically deformable toward mutually inner
directions, retaining grooves which retains on the hole edge of the
penetrating hole being formed on an outer edge of each of the
retaining pieces.
6. The electronic control unit as claimed in claim 2, wherein the
elastic deformation section is formed on each of both ends of the
earth connecting member.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. application Ser.
No. 13/446,086, filed Apr. 13, 2012, which claims priority from
Japanese Patent Application Nos. 2011-170613 and 2011-170614, filed
on Aug. 4, 2011, the disclosures of which are expressly
incorporated by reference herein.
BACKGROUND OF THE INVENTION
[0002] (1) Field of the Invention
[0003] The present invention relates to an electronic control unit
to control, for example, an anti-lock brake system (ABS) for a
vehicle.
[0004] (2) Description of Related Art
[0005] A Japanese Patent Application First Publication (Tokkai) No.
2007-290596 published on Nov. 8, 2007 (which corresponds to a
United States Patent Application Publication No. US2007/0252431
published on Nov. 1, 2007) exemplifies a previously proposed
electronic control unit used for, for example, the anti-lock brake
system (ABS) of the vehicle and so forth.
[0006] The previously proposed electronic control unit described
above includes: a liquid pressure control block made of an aluminum
alloy material and electrically conducted to a vehicle body; a
resin made casing installed at an upper end section of the liquid
pressure control block; a cover installed at an upper part of the
casing; and a circuit board housed in the casing.
[0007] An electrically connecting member is attached onto the
casing. One end of this electrically connecting member is connected
to a grounding section of the circuit board within the casing and
the other end thereof is contacted under pressure onto an upper
surface of the liquid pressure control block. This causes an
electrical conduction between the liquid pressure control block and
the grounding section of the circuit board to provide the same
electrical potential for both of the block and the grounding
section. Thus, electrical noises of electronic components mounted
on the circuit board can be reduced.
SUMMARY OF THE INVENTION
[0008] However, in the previously proposed electronic control unit
described above, in a case where the cover is made of a metal, the
circuit board and the cover are disposed in the proximity to each
other. Hence, there is a possibility that electrical noises
generated on the circuit board are radiated toward an external side
via the cover.
[0009] In addition, since the liquid pressure control block is
provided with drive actuators such as an electric motor and
pressure increasing/decreasing valves. There is a possibility that
the electrical noises from these drive actuators and so forth are
transmitted onto the cover via the casing so as to be radiated
toward an external to the electronic control unit.
[0010] It is, therefore, an object of the present invention to
provide an electronic control unit which is capable of effectively
reducing the electrical noises transmitted from the circuit board
or so forth to a cover member.
[0011] According to one aspect of the present invention, there is
provided with an electronic control unit, comprising: a metallic
control block in which a plurality of control equipments are
installed; a metallic cover member fitted onto the metallic control
block; and an electronic control mechanism retained between the
metallic control block and the metallic cover member to drive the
control equipments, the electronic control mechanism including: a
bus bar constituent made of a resin material and having a power
electronic circuit to drive the control equipments; and a print
board to control the drive of the control equipments via the bus
bar constituent, the print board on which a plurality of electronic
parts are mounted being fixed onto the bus bar constituent by means
of a metallic fixture section and an electrically conducting
section being disposed to electrically conduct the metallic control
block to the metallic cover member to provide the same electric
potential for both of the metallic cover member and the metallic
control block.
[0012] According to another aspect of the present invention, there
is provided with an electronic control unit, comprising: a metallic
control block in which a plurality of control equipments are
installed; a metallic cover member fitted onto the metallic control
block; and an electronic control mechanism retained between the
metallic control block and the metallic cover member to drive the
control equipments, the electronic control mechanism including: a
bus bar constituent made of a resin material and having a power
electronic circuit to drive the control equipments; and a print
board to control the drive of the control equipments via the bus
bar constituent, the print board on which a plurality of electronic
parts are mounted being fixed onto the bus bar constituent by means
of a metallic fixture section and an electrically conducting
section being disposed to electrically conduct the metallic control
block to the metallic cover member via at least one of the fixture
section and the bus bar constituent to provide the same electric
potential for both of the metallic cover member and the metallic
control block.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is an exploded perspective view representing a first
preferred embodiment of an electronic control unit according to the
present invention.
[0014] FIG. 2 is a laterally cross sectioned view of the electronic
control unit in the first embodiment shown in FIG. 1.
[0015] FIG. 3 is an essential part enlarged view of FIG. 2.
[0016] FIG. 4 is an exploded perspective view representing a second
preferred embodiment of the electronic control unit according to
the present invention.
[0017] FIG. 5 is an essential part expanded cross sectioned view of
the electronic control unit in the second embodiment according to
the present invention shown in FIG. 4.
[0018] FIG. 6 is a perspective view for explaining a grounding
(earth) connecting member and a corresponding penetrating hole
through which the earth connecting member is inserted to be applied
in the second embodiment shown in FIGS. 3 and 4.
[0019] FIG. 7 is an enlarged cross sectional view for explaining a
state in which the earth connecting member is retained into the
penetrating hole shown in FIG. 6.
DETAILED DESCRIPTION OF THE INVENTION
[0020] Reference will, hereinafter, be made to the drawings in
order to facilitate a better understanding of the present
invention. Preferred embodiments in which an electronic control
unit according to the present invention is applicable to the ABS
will, hereinafter, be described in details on a basis of the
accompanied drawings.
First Embodiment
[0021] FIGS. 1, 2, and 3 shows a first preferred embodiment of an
electronic control unit which is applicable to an electronic
control unit for the ABS (Anti-lock Brake System) of the
vehicle.
[0022] First, a rough explanation of the ABS will be made below.
The ABS includes: a master cylinder generating a brake pressure in
accordance with a depression quantity (depth) of a brake pedal (not
shown); a main passage configured to communicate the master
cylinder with each of wheel cylinders at front left and right road
wheels (FL, FR) and rear left and right road wheels (RL, RR);
normally open solenoid type pressure increasing valves installed in
the main passage and normally close solenoid type pressure
decreasing valves installed in the main passage (as will be
described later) to control a brake liquid pressure from the master
cylinder to each of the wheel cylinders; a pump installed in the
main passage to discharge a brake liquid pressure to each of the
wheel cylinders; and a reservoir tank configured to reserve the
brake liquid exhausted from each wheel cylinder via the
corresponding pressure decreasing valve(s) and supply the brake
liquid to the main passage according to the operation of the
pump.
[0023] Each of the pressure increasing valves controls the brake
liquid pressure from the master cylinder to be enabled to be
supplied to each wheel cylinder and each of the pressure decreasing
valves opens the valve thereof when an inner pressure of each of
the wheel cylinders is equal to or higher than a predetermined
value to generate slips on the corresponding one of the road wheels
to return the brake liquid to the reservoir tank.
[0024] The above-described pressure increase and decrease are an
open-and-closure controlled by means of the electronic control unit
in this embodiment so that the brake liquid pressure within each of
the wheel cylinders is controlled in a pressure increase mode, a
pressure decrease mode, and a pressure holding mode.
[0025] The electronic control unit is, as shown in FIGS. 1 and 2,
equipped with a casing 1 and an electronic control mechanism 2
retained onto casing 1.
[0026] Casing 1 includes: a liquid pressure control block 3 (a
metallic control block) located at a lowest side of casing 1 and
conducted electrically to a vehicle body; and a cover member 4
fitted onto electronic control mechanism 2 from an upper side of
electronic control mechanism 2 assembled on an upper part of liquid
pressure control block 3.
[0027] Liquid pressure control block 3 is integrally formed
substantially in a cubic shape and made of an aluminum alloy
material. A plurality of retaining holes 7 through which lower
parts of a plurality of pressure increasing valves 5 and pressure
decreasing valves 6 are inserted and retained are formed along a
vertical direction of this control block 3 and a solenoid casing 8
(coil unit), made of a metal, coupled to upper end sections of
respective pressure increasing valves 5 and pressure decreasing
valves 6, and into which electromagnetic coils of these valves 5, 6
are housed is retained. A lower surface of this solenoid casing 8
is contacted on an upper surface 3a of liquid pressure control
block 3 and electrically conducted thereto.
[0028] Liquid pressure units such as the main passage and the sub
passages communicated to pressure increasing valves 5 and pressure
decreasing valves 6 (these valves constitute a part of the liquid
pressure control equipments), a pump to supply a brake liquid
pressure to the main passage, and an electric motor to drive the
pump are installed within an inside of liquid pressure control
block 3. Furthermore, on upper four corner parts of liquid pressure
control block 3, female screw holes 9 into which fixture bolts 14
are screwed are formed.
[0029] Cover member 4 is formed along an outer shape (profile) of
liquid pressure control block 3 in a thin dish shape and is made of
an aluminum alloy material. Cover member 4 includes: an upper wall
4a in a flat plate shape; an annular side wall 4b formed integrally
on an outer peripheral edge of upper wall 4a; and a rectangular
frame shaped flange section 4c continuously integrated onto a lower
end outer peripheral portion of side wall 4b.
[0030] Above-described flange section 4c is provided with a
plurality of retaining pieces 10, each of which retains on an upper
end section of an outer periphery of a bus bar constituent 11 in a
state in which this cover member 4 is fitted onto a print board 12
as will be described later. These retaining pieces 10 are projected
toward a downward direction of cover member 4. Each retaining piece
10 is installed at a substantially center position of each side of
flange section 4c. Retaining pawls 10a are respectively formed on
tip end outer sides of retaining pieces 10. It should be noted that
print board 12 (or called, circuit board) includes a printed
circuit board and a printed wiring board and is used in a broad
sense of term.
[0031] Electronic control mechanism 2 interposed between liquid
pressure control block 3 and cover member 4 includes: a power
electronic circuit which outputs switching signals on
open-and-closure operations to respective pressure increasing and
decreasing valves 5, 6 and supplies an electric power to a stator
of above-described electric motor; bus bar constituent 11
integrally formed with an electromagnetic filter circuit to reduce
radio noises (electromagnetic noises); and print board 12 arranged
in an overlapped state on the upper part of bus bar constituent 11
and which is a circuit board to control the drive of the electric
motor and so forth.
[0032] Bus bar constituent 11 is formed in a block plate shape by
means of molding. As shown in FIG. 1, bus bar constituent 11 has
the profile formed in substantially rectangular shape along the
profile of liquid pressure control block 3 and cover member 4. Four
engagement sections 13 which elastically engages with penetrating
holes located at insides of retaining pawls 10a of retaining pieces
10 of cover member 4. Furthermore, bolt inserting holes 11a into
which fixture bolts 14 are inserted are penetrated in the vertical
direction at corners of the outer peripheral part of bus bar
constituent 11.
[0033] In addition, an annular seal 15 which is elastically
contacted on upper surface 3a at the outer peripheral part of
liquid pressure control block 3 to seal liquid pressure control
block 3 is fixed onto a lower end of the outer peripheral edge of
bus bar constituent 11 via a fitting groove formed on bus bar
constituent 11, as shown in FIG. 2.
[0034] A connector constituent 16 constituted by a power supply
connector connected to a battery, a motor connector to supply an
electric power to the electric motor, and a signal connector which
provides a transmission passage of various kinds of signals such as
signals from a resolver, a CAN (Controller Area Network)
communication line, and I/O units is integrally installed on a
front end section of bus bar constituent 11.
[0035] Furthermore, many power distribution patterns such as the
power distribution patterns of a power supply negative pole side
bus bar connected to the power supply connector, a power supply
positive pole side bus bar connected to the power supply connector,
a motor output bus bar for motor output, and a power supply
positive pole side bus bar are formed on a surface or inner part of
bus bar constituent 11.
[0036] A plurality of terminal groups 17 connected to the power
supply connector, the motor connector, and the signal connector and
a plurality of terminal groups 18 for control signals to drive
semiconductor switching elements (FET (Field Effect Transistor))
and a motor relay are projected from upper surface 11b of bus bar
constituent 11.
[0037] In addition, electronic parts of the power electronic
circuit, a plurality of aluminum electrolyte capacitors, normal
coils, common coils, and a plurality of ceramic capacitors which
are components of the filter electronic circuit are mounted on a
lower surface 11c of bus bar constituent 11.
[0038] Furthermore, a single cylindrical section 20 which fixedly
supports print board 12 by means of screw member 19 (which is a
metallic fixture section) is integrally extended in the upward
direction of bus bar constituent 11 from a predetermined position
of upper surface 11b of bus bar constituent 11.
[0039] Above-described screw member 19 includes: a head section 19a
located at one end side of screw member 19 and on which a
cross-shaped groove for a driver jig is formed at an upper surface
of head section 19a; and a shank 19b located at the other end side
of head member 19, integrally installed on the head section 19a via
a flange section 18c provided at a lower surface of head section
19a, and whose outer peripheral side is threaded as a male
screw.
[0040] Cylindrical section 20 serves to form a gap S having a
predetermined width between bus bar constituent 11 and print board
12 and cylindrical section 20 has an axial length such that the
electronic parts as will be described later actually mounted on an
upper surface of bus bar constituent 11 and a lower surface of
print board 12 are not interfered against one another.
[0041] In addition, a penetrating hole 21 penetrated continuously
through bus bar constituent 11 is formed along the vertical
direction of bus bar constituent 11 and a metallic sleeve 22 is
integrally fixed on an inner peripheral surface of penetrating hole
21 at cylindrical section 20 side by means of a press fitting or so
forth. An inner peripheral surface of this sleeve 22 is formed with
the female screw to which the male screw having an outer periphery
of shank 19b of screw member 19 is screwed.
[0042] Print board 12 is formed substantially in a thin dish plate
of a substantially square shape with a synthetic resin material, as
shown in FIGS. 2 and 3. A screw inserting hole 23 is penetrated at
a position corresponding to cylindrical section 20 of bus bar
constituent 11 located at a center of print board 12. A
substantially doughnut shaped electrically conducting piece 24 is
integrally formed on a hole edge of an upper surface 12a of print
board 12 (namely, the hole edge at a side through which screw
member 19 is inserted through which screw inserting hole 23). This
electrically conducting piece 24 is formed with an inserting hole
24a through which shank 19b of screw member 19 is inserted at the
center thereof and flange section 19c of screw member 19 is seated
on an exposed upper surface of this electrically conducting piece
24. It should be noted that a reference numeral 25 shown in FIGS. 2
and 3 denotes an earth plate as will be described later.
[0043] On this print board 12, a plurality of electronic parts
including a microcomputer, for example, a semiconductor switching
device (MOS-FET), an acceleration sensor 30, and so forth are
actually mounted. In this addition, a power distribution pattern
which is a part of a control circuit is formed at an inner part of
print board 12. A drive signal to be supplied to the electric motor
is produced by means of this print board 12. It should be noted
that acceleration sensor 30 is mounted in a proximity to a position
of electrically conducting piece 24 at which print board 12 is
fixed by means of screw member 19.
[0044] Terminal pins 17a and 18a of respective terminal groups 17,
18 of bus bar constituent 11 are inserted into a plurality of
terminal holes 12c formed on one side section and formed on the
other side section of this print board 12 and connected to
corresponding electronic parts by soldering.
[0045] Acceleration sensor 30 is of a tuning fork type and a
detuning frequency is 500 through 900 Hz. If print board 12 is
resonated at the above-described detuning frequency, this
acceleration sensor 30 is resonated, an output of acceleration
sensor 30 being drifted (offset).
[0046] An oscillation frequency of print board 12 can be raised to
1000 Hz through 1300 Hz at a proximity to the fixation section of
screw member 19 through print board 12. Therefore, it is
advantageous for the drift of the sensor output since this
oscillation frequency is not overlapped with the detuning frequency
of acceleration sensor 30.
[0047] Then, an electrically conducting section which electrically
conducts both of liquid pressure control block 3 and cover member 4
via screw member 19 as shown in FIGS. 1, 2, and 3 is interposed
between liquid pressure control block 3 and cover member 4.
[0048] This electrical conducting section includes: earth plate 25
installed at head section 19a of screw member 19 and elastically
contacted on lower surface 4d of upper wall 4a of cover member 4;
and an earth spring 26 elastically installed between shank 19b of
screw member 19 and solenoid casing 8.
[0049] Above-described earth plate 25 is an electrically conductive
elongated thin plate folded substantially in a recess form and
includes: a flat base section 25a; slanted pieces 25b, 25b which
are projected and raised toward a direction at which cover member 4
is faced from both side edges of base section 25a. Base section 25a
is provided with an inserting hole 25c through which shank 19b of
screw member 19 is inserted at the center thereof and is grasped
and fixed between flange section 19c of screw member 19 and
conducting piece 24. Upper end sections 25d, 25d of both slanted
pieces 25b, 25b are folded toward outer directions and elastically
contacted on lower surface 4d of cover member 4.
[0050] Earth spring 26 is formed in a coil spring like shape and is
made of a metallic member. An upper end section (26a) of earth
spring 26 is housed and held within penetrating hole 21 and an
upper end edge (26a) of earth spring 26 is elastically contacted on
a lower end edge of shank 19b of screw member 19. A lower end edge
(26b) of a lower end section (26b) of earth spring 26 projected
toward a downward direction of earth spring 26 is elastically
contacted on an upper surface (a black point T in FIG. 1) of
solenoid casing 8.
[0051] (Assembly Procedure)
[0052] Hereinafter, an assembly procedure of the electronic control
unit in the first embodiment will be explained. First, a liquid
pressure unit (or a hydraulic pressure unit) is previously prepared
with respective pressure increasing and pressure decreasing valves
5, 6, the pump, the electric motor, and the reservoir previously
assembled into liquid pressure control block 3. In addition, the
power distribution patterns of the power electronic circuit and the
filter electronic circuit are modularized to integrally form bus
bar constituent 11 and the plurality of electronic parts such as
the electrolyte capacitors and so forth are mounted on bus bar
constituent 11. Furthermore, the power distribution patterns of
print board 12 and various kinds of electronic parts such as
respective semiconductor switching elements are mounted on print
board 12.
[0053] In addition, earth plate 25 is provisionally attached onto
shank 19b of screw member 19 via inserting hole 25c of earth plate
25.
[0054] Subsequently, print board 12 is mounted on the upper surface
of cylindrical section 20 integrally formed on bus bar constituent
11 with the lower surface of the hole edge of screw inserting hole
23 of print board 12 contacted on the upper surface of cylindrical
section 20. At the same time, a positioning is needed to be made
for respective terminal pins 17a, 18a corresponding to respective
terminal holes 12c and their insertions are needed to be carried
out.
[0055] Next, in a state in which earth plate 25 is provisionally
attached onto bus bar constituent 11, the tip of shank 19b of screw
member 19 is inserted into sleeve 22 from bolt inserting hole 24a
of electrically conducting piece 24 and screw member 19 is directly
and strongly screwed with a predetermined torque via the male and
female screws described above.
[0056] At this time, base section 25a of earth plate 25 is screwed
and fixed in a grasped state between flange section 19c of screw
member 19 and electrically conducting piece 24. At the same time,
the whole earth spring 26 is compressed and deformed so that upper
end edge 26a of earth spring 26 is elastically contacted on the
lower end edge of shank 19b and lower end edge 26b of earth spring
26 is elastically contacted on the upper surface of solenoid casing
8.
[0057] Consequently, print board 12 is fixed to an upper position
of bus bar constituent 11 and an electrical conductivity between
print board 12 and solenoid casing 8 is secured.
[0058] Thereafter, respective terminal pins 17a, 18a are soldered
to print board 12 in a state in which terminal pins 17a, 18a are
inserted into respective terminal holes 12c. Thus, print board 12
and electronic parts connected to terminal pins 17a, 18a are
mutually connected to each other.
[0059] Next, after an adhesive is applied to the outer periphery of
cover member 4, cover member 4 is fitted from above onto print
board 12 and bus bar constituent 11 and each retaining pawl 10a of
the corresponding one of retaining pieces 10 is engageably inserted
into the corresponding retaining hole of each retaining section 13
of bus bar constituent 11 utilizing an elastic deformation. Thus,
by retaining each retaining pawl 10a into lower hole edge of the
corresponding retaining hole, cover member 4 can easily be
assembled onto bus bar constituent 11.
[0060] Subsequently, bus bar constituent 11 is positioned and
provisionally mounted on upper surface 3a of liquid pressure
control block 3 via annular seal 15. Thereafter, each fixture bolt
14 is tightened to fix bus bar constituent 11 onto liquid pressure
control block 3. Thereafter, earth spring 26 is previously inserted
into penetrating hole 21 of bus bar constituent 11. Lower end edge
26b is contacted on the upper surface of solenoid casing 8. Thus,
an assembly work of each component described above is
completed.
[0061] At this time, the upper surfaces of both upper end sections
25d, 25d of earth plate 25 are elastically contacted on lower
surface 4d of upper wall 4a of cover member 4 according to the
elastic force exerted by earth plate 25 itself. Base section 25a of
earth plate 25 is grasped between head section 19a of screw member
19 and print board 12 and is electrically conducted to screw member
19 and print board 12. Head section 19a of screw member 19 is
elastically contacted on earth spring 26 and is electrically
conducted to a shoulder section of solenoid casing 8. Furthermore,
since solder casing 8 is electrically contacted on liquid pressure
control block 3. Thus, the electrical conductivity between cover
member 4 and liquid pressure control block 3 is secured.
[0062] As described above, in the first embodiment, liquid pressure
control block 3 and cover member 4 are electrically conducted by
means of spring member 19, earth plate 25, and earth spring 26 so
that both of liquid pressure control block 3 and cover member 4 can
provide the same potential. Therefore, the electrical noise
transmitted from print board 12 to cover member 4 and a magnetic
field variation due to a variation (switching) in the drive current
of the electric motor or the valve solenoids can cause the
electrical noise generated on a current line of the motor or
solenoid as the noise to flow toward liquid pressure control block
3, namely, a vehicle body. Thus, the electrical noise on cover
member 4 can effectively be reduced. Hence, noise superpositions on
signal lines installed on print board 12 can be suppressed.
[0063] In addition, since the electrical noise generated on print
board 12 via electrically conducting piece 24 can directly be
transmitted to liquid pressure control block 3, the electrical
noise generated on print board 12 can effectively be reduced.
[0064] In addition, since the electrical noise transmitted from the
external to cover member 4 can be caused to flow on the liquid
pressure control block 3, the noise transmission to print board 12
can sufficiently be suppressed.
[0065] Furthermore, since acceleration sensor 30 mounted on print
board 12 is disposed in the proximity to the fixation position of
screw member 19. Therefore, since the vibration transmission to
acceleration sensor 30 can effectively be blocked, the reduction in
the acceleration detection accuracy can be suppressed.
[0066] In addition, the electrical conductivity between both of
liquid pressure control block 3 and cover member 4 is secured
utilizing readily available screw member 19. Hence, the reduction
in a manufacturing cost can be achieved.
[0067] That is to say, with earth plate 25 fixed onto print board
12 by means of a (screw or tightening) torque of screw member 19
and earth spring 26 is elastically contacted on solenoid casing 8
utilizing a screw tightening force of screw member 19. Hence, as
compared with a case where another earth connecting member is
formed and fixed onto the bus bar constituent, the structure can be
simplified and the manufacturing work can be facilitated.
[0068] In addition, lower end edge 26b of earth spring 26 is
elastically contacted on readily available solenoid casing 8
without direct elastic contact on liquid pressure control block 3.
Thus, an axial length of earth spring 26 can sufficiently be
shortened. Thus, as described above, when a compression force is
given to earth spring 26 with screw member 19 tightened, an
unintentional fall in a radial direction of earth spring 26 and a
twisted deformation does not occur. Thus, it becomes possible to
always maintain a linearity. Hence, a stable elastic contact action
for solenoid casing 8 can be obtained.
[0069] Furthermore, a mere tightening of screw member 19 onto
continuous holes 22, 23 can simultaneously achieve the fixation of
earth plate 25 on print board 12 and an elastic contact force of
earth spring 26. Hence, the assembly operation for these parts can
become facilitated.
[0070] Furthermore, cover member 4, print board 1, and solenoid
casing 8 are always electrically contacted on one another according
to earth plate 25 and a spring force of earth spring 26 via spring
force 19. Hence, even if a vibration is developed, the electrical
conductivity between liquid pressure control block 3 and cover
member 4 can always stably be maintained.
[0071] Especially, earth plate 25 is elastically contacted against
lower surface 4d of upper wall of cover member 4 and earth spring
26 is elastically contacted on solenoid casing 8, respectively.
Hence, a degree of freedom in the length of the whole conducting
section including screw member 19 is increased.
[0072] Consequently, even if a dimensional error and an assemble
error in the vertical direction of each of liquid pressure control
block 3, cover member 4, and bus bar constituent 11 are developed,
a deflective deformation (deflection) in a length direction of each
of earth plate 25 and earth spring 26 can absorb each of the errors
described above. Hence, the positioning and the assembly work can
be facilitated.
[0073] In addition, since earth plate 25 and earth spring 26 are
arranged at each dead space of the upper part of the screw member
19 and lower part of screw member 19, an effective utilization of
these dead spaces can be achieved. Consequently, a large sizing of
the unit and a modification of a circuit component arrangement can
be suppressed.
[0074] Furthermore, in this embodiment, the power distribution
pattern of the power electronic circuit and the filter electronic
circuit and so forth are integrally modularized to constitute thin
bus bar constituent 11. Hence, it becomes possible to reduce a
height of the electronic control unit in the vertical direction of
the electronic control unit. The small sizing of the whole unit (or
thinning) can be achieved and a light weighting can also be
achieved.
[0075] In addition, in this embodiment, cover member 4 can be
united to bus bar constituent 11 with a mere one-touch operation
utilizing each retaining piece 11 and each retaining section 13.
Hence, the assemble work of this cover member 4 becomes
preferable.
[0076] The present invention is not limited to the structure of the
preferred embodiment. Earth plate 25 and earth spring 26 are not
electrically conducted to each other via the screw member 19 but,
for example, a cylindrically shaped electrically conducting
material is fitted onto the outer periphery of shank 19b of screw
member 19 so that both of earth plate 25 and earth spring 26 may be
conducted via this electrically conducting material.
[0077] In addition, as the fixture section described above, the
fixture section may be constituted not only by a bolt-and-nut
structure but also by a rivet having the electrically
conductivity.
[0078] Furthermore, earth plate 25 may be constituted by only
single slant piece 25b projected at one side of base section 25a.
In addition, it is, for example, possible to arbitrarily modify the
shape and structure of casing 1 and bus bar constituent 11.
[0079] Furthermore, as an applicable unit of the electronic control
unit according to the present invention, the present invention is
applicable to a traction control system (TCS) in addition to the
ABS described above.
Second Embodiment
[0080] The electronic control unit in a second preferred embodiment
according to the present invention will hereinafter be made with
reference to the attached drawings of FIGS. 4 through 7.
[0081] It should be noted that the parts having the same reference
numerals in the second embodiment designate like elements in the
first embodiment but difference points from the first embodiment
will be described below.
[0082] The electronic control unit is applicable to the ABS in the
same way as the first embodiment. In the ABS, respective pressure
increasing or decreasing valves are power supplied to turn on and
not power supplied to turn off on a basis of a control signal from
the electronic control unit.
[0083] It should be noted that solenoid casing 8 in the first
embodiment generally corresponds to a coil unit 8' in the second
embodiment. In an inner part of liquid pressure control block 3,
the plunger pump is installed. However, in place of the plunger
pump, a reversible gear pump can be used. Cover member 4 is made of
aluminum alloy material functioning as a heat sink and is formed
along the profile of liquid pressure control block 3. Print board
12 is arranged on the upper part of bus bar constituent 11.
[0084] Furthermore, single cylindrical body 20 is integrally
installed to fix and support by means of print board 12 through
screw member 19 at the predetermined position of upper surface 11b
of bus bar constituent 11. On an inner peripheral surface of
cylindrical section 20, a metallic cylindrical envelope section 20a
is integrally fixed and a female screw section to which screw 19 is
screwed is formed on the inner peripheral surface of cylindrical;
envelope section 20a.
[0085] In addition, as shown in FIGS. 4 through 7, a penetrating
hole 210 which is penetrated in the vertical direction is formed in
the proximity to cylindrical section 20 of bus bar constituent 11.
This penetrating hole 210 is formed in a substantially plane
surface view of a letter T shape and is constituted by an inserting
hole section 210a formed in substantially an rectangular shape; and
an escaping hole 210b located at the substantially rectangular
shape and located at substantially center position at one side of
inserting hole section 210a.
[0086] Print board 12 is formed in a thin plate of an approximately
square shape made of the synthetic resin and screw inserting hole
22 is penetrated at a predetermined position corresponding to
cylindrical member 20 of bus bar constituent 11. In addition, when
print board 12 is mounted from the above side of bus bar
constituent 11, a lower surface side hole edge of screw inserting
hole 22 is contacted on the upper surface of cylindrical section
20. Thus, the electronic parts are not interfered against one
another according to a presence of gap C (refer to FIG. 5).
[0087] Then, in the second embodiment, an earth connecting member
230 which is the electrically connecting member is fixedly fitted
into penetrating hole 210 of bus bar constituent 11.
[0088] This whole earth connecting member 230 is, as shown in FIG.
6, integrally formed in a flat plate shape made of an electrically
conductive member such as copper and includes: a base section 240
in a rectangular shape positioned at penetrating hole 210; elastic
deformation sections 250, 260 which are both end sections extended
in the vertical direction from upper and lower end edges of base
section 240; and a pair of left and right clip pieces 270, 270
which are retaining sections installed on both end sections of base
section 240. In addition, earth connecting member 230 has, as shown
in FIG. 5, the whole length set so as to be longer than the
straight distance between upper surface 3a of liquid pressure
control block 3 and lower surface 4c of upper wall 4a of cover
member 4, when cover member 4 is assembled onto liquid pressure
control block 3 via bus bar constituent 11.
[0089] Base section 240 is formed in the flat plate shape and has a
vertical length L which is slightly longer than the vertical length
of inserting hole section 210a of penetrating hole 210.
[0090] Both of elastic deformation members 250, 260 are constituted
by extended sections 250a, 260a extended in the vertical direction
from upper and lower ends of base section 240 and folded in curved
shapes toward respective outer sides of base section 240; and
contacting sections 250b, 260b integrally formed on tips of
respective extended sections 250a, 260a and having tip sections
folded in the curved shape mutually toward inner sides of base
section 240. Outer surfaces of respective contacting sections 250a,
260b are elastically contacted on upper surface 3a of liquid
pressure control block 3 and lower surface 4c of upper wall 4a of
cover member 4.
[0091] Each clip piece 270, 270 is constituted by a shoulder
section 270a, 270a integrally installed on base section 240 in a
lateral direction from a substantially center position of base
section 240; and leg pieces 270b, 270b extended toward the lower
direction of earth connecting member 230 with constant spatial
intervals of c, c. An upper end edge of each shoulder section 270a,
270a is slanted in the downward direction as shown in FIG. 6. A
retaining groove 270c, 270c is formed at each of both sides of
respective leg pieces 270b, 270b having a slightly larger size than
a wall thickness of the upper wall of bus bar constituent 11 and
retaining groove sections 270d, 270d which are retained on lower
part hole edges of inserting hole sections 210a of penetrating hole
210.
[0092] [Assembly Procedure]
[0093] Hereinafter, the assemble procedure of the electronic
control unit in the second embodiment described above will be
described below. Each pressure increasing valve 5, each pressure
decreasing valve 6, the plunger pump, the electric motor, the
reservoir tank, and so forth are previously assembled on liquid
pressure control block 3 to constitute the liquid pressure unit
(the hydraulic pressure unit). In addition, the power distribution
patterns of the power electronic circuit and the filter electronic
circuit are modularized to form integrally bus bar constituent 11
and the plurality of electronic parts are mounted on bus bar
constituent 11. Furthermore, the power distribution patterns of
print board 12 and various kinds of electronic parts such as
respective semiconductor switching elements are mounted.
[0094] On the other hand, earth connecting member 23 is retained
and fixed onto penetrating hole 21 of bus bar constituent 11. That
is to say, as shown in FIG. 6, earth connecting member 230 is
carried such that base section 240 side is faced toward inserting
hole section 210a and is inserted directly through penetrating hole
210 from above. At this time, lower elastic deformation section 250
is inserted through both of insertion purpose hole section 210a and
escaping purpose hole section 210b of penetrating hole 210. When
this deformation section 250 is continued to be pushed, retaining
pawls 270d, 270d of respective clip pieces 270, 270 are elastically
deformed and mutually inserted into the mutually opposing inside
parts of inserting hole section 210a via respective gaps c, c
elastically contacting retaining pawls 270d, 270d of both clip
pieces 270, 270 on the upper end edge and the inner surface
opposing against hole 210a. When the upper and lower end edges of
respective retaining grooves 270c, 270c are positioned at inserting
hole sections 210a, both of clip pieces 270, 270 are elastically
recovered and respective retraining grooves 270c, 270c are retained
on upper and lower opening edges of inserting hole section
210a.
[0095] Thus, earth connecting member 230 is firmly retained and
fixed onto bus bar constituent 11 with a mere one-touch
operation.
[0096] Subsequently, print board 12 is mounted on the upper surface
of cylindrical section 20 of bus bar constituent 11 while print
board 12 is contacted on the lower surface hole edge of screw
inserting hole 22. At the same time, each terminal pin 17a, 18a
corresponding to each terminal hole 12c is positioned and inserted
into each terminal hole 12c.
[0097] Thereafter, screw 19 is screwed onto the female screw
section of cylindrical section 20a from screw inserting hole 22 to
fix print board 12 onto the upper position of bus bar constituent
11. Thereafter, each terminal pin 17a, 18a is soldered onto print
board 12 in the state in which each terminal pin 17a, 18a is
inserted into each terminal hole 12c. Thus, mutual interconnections
between terminal pins and holes of print board 12 can be made.
[0098] Next, as shown in FIG. 5, an adhesive 300 is coated on an
outer periphery of cover member 4. Thereafter, print board 12 is
fitted into bus bar constituent 11 from above and each retaining
pawl 10a of each retaining piece 10 is inserted into the retaining
hole of each retaining section 13 of bus bar constituent 11
utilizing the elastic deformation. At this time, each retaining
pawl 10a is retained on the lower section hole edge of the
corresponding retaining hole. Thus, print board 12 can easily be
assembled onto bus bar constituent 11.
[0099] Next, after bus bar constituent 11 is provisionally mounted
by positioning bus bar constituent 11 on the upper surface of
liquid pressure control block 3 via annular seal 15, each fixture
bolt 14 is used to fix bus bar constituent onto liquid pressure
control block 3. At this time, the lower end outer surface of
curved section 250b of elastic deformation section 250 located at a
lower side of earth connecting member 230 is elastically contacted
on upper surface 3a of liquid pressure control block 3. Thus, the
assembly operation of each component is completed.
[0100] At this time, the upper surface of curved section 260b of
elastic deformation section 260 of earth connecting member 230 is
elastically contacted on lower surface 4c of upper wall 4a of cover
member 4.
[0101] As described above, in the second embodiment, earth
connecting member 230 is used to electrically conduct liquid
pressure control block 3 to cover member 4. Thus, both of liquid
pressure control block 3 and cover member 4 are electrically at the
same potential. Thus, since the electrical noise transmitted from
circuit board 12 to cover member 4 can be caused to flow to liquid
pressure control block 3 side. Hence, the electrical noise on cover
member 4 can effectively be reduced.
[0102] In addition, earth connecting member 23 is always
elastically contacted on both of upper surface 3a of liquid
pressure control block 3 and lower surface 4c of the upper wall of
cover member 4 according to the elastic deformation of respective
elastic deformation sections 250, 260. Hence, even if the vibration
is developed, the electrical conductivity between liquid pressure
control block 3 and cover member 4 can, always, stably be
maintained.
[0103] Especially, since both of elastic deformation sections 250,
260 are formed in the curved shape, the degree of freedom of the
whole length of earth connecting member 230 can be improved.
[0104] Consequently, even if the vertical dimensional error and
assembly error of liquid pressure control block 3, cover member 4,
and bus bar constituent 11 are generated, the large twist
deformation in the elongated direction according to the curved
shape of each elastic deformation section 250, 260 can be made so
that each error described above can be absorbed. Thus, the
positioning work and assemble operation are possible.
[0105] Furthermore, earth connecting member 230 can be retained and
fixed strongly on penetrating hole 210 of bus bar constituent 11
and, as described hereinabove, earth connecting member 230 can be
retained and fixed. Thus, this fixation work can extremely be
facilitated.
[0106] In addition, since earth connecting member 230 is arranged
at a dead space within liquid pressure control block 3, cover
member 4, and bus bar constituent 11, an effective utilization of
the dead space can be made. The other advantages in the case of the
second embodiment are the same as those in the case of the first
embodiment.
[0107] The present invention is not limited to the preferred
embodiments. For example, it is possible to connect earth
connecting member 230 to liquid pressure control block 3 via cover
member 4 and print board 12. According to this, the electrical
noise generated on print board 12 can directly be transmitted to
liquid pressure control block 3.
[0108] Furthermore, for example, it is possible to arbitrarily
modify the shapes and structures of casing 1 and bus bar
constituent 11. In addition, as described above, the object to be
applied includes an electronic control unit of the traction control
system (TCS) in addition to the ABS. Furthermore, elastic
deformation sections 250, 260 may be installed on only one end
section of earth connecting member 230.
[0109] It should be noted that a hydraulic pressure circuit
including, the electric motor, the pressure decreasing and
increasing valves, the master cylinder, the reservoir, the master
cylinder, and the respective wheel cylinders described above is
exemplified by a United States Patent Application Publication No.
2007/0252431 published on Nov. 1, 2007, a U.S. Pat. No. 7,997,665
issued on Aug. 16, 2011, and a U.S. Pat. No. 7,290,840 issued on
Nov. 6, 2007 (which are herein incorporated by reference).
[0110] Technical ideas grasped by the present invention will be
described hereinbelow.
(1) The electronic control unit as claimed in claim 3, wherein the
fixture section is constituted by a screw member, a screw
penetrating hole through which the screw member is inserted is
penetrated on a predetermined position of the print board, an
electrically conductive piece is disposed on a hole edge of the
screw penetrating hole at a screw inserting side of the screw
penetrating hole, and the earth plate is fixedly grasped between
the electrically conductive piece and a head section of the screw
member. (2) The electronic control unit as claimed in claim 3,
wherein the earth plate includes: a flat base piece fixed to the
fixture section; and slanted pieces projected from both ends of the
base piece toward the cover member, the slanted pieces being formed
in a recess shape together with the base piece, each upper end of
the slanted pieces being bent toward an outer direction from the
recess shaped base piece and slanted pieces to elastically bring an
upper surface of each upper end of the slanted pieces into contact
with the lower surface of the cover member. (3) The electronic
control unit as claimed in claim 5, wherein a cylindrical section
is integrally formed on an upper surface of the bus bar constituent
and a metallic sleeve is integrally fixed onto an inner periphery
of the cylindrical section, a female screw being formed on the
metallic sleeve and on which the screw member is screwed. (4) The
electronic control unit as claimed in claim 5, wherein one end of
the earth spring is elastically contacted on a tip edge of a shank
of the screw member and the other end of the earth spring is
elastically contacted on an upper surface of the solenoid casing.
(5) The electronic control unit as claimed in claim 10, wherein the
earth connecting member is formed in a rectangular plate shape and
the elastic deformation section of the earth connecting member is
bent to form a curve. Since the elastic deformation section is
formed in the curved shape (as described in item (5)), the length
of the electric connecting member is improved and the electrical
connection state can always be assured even if the length between
the liquid pressure control block and the cover member is modified.
(6) The electronic control unit as claimed in claim 11, wherein the
retaining sections comprise: a plate-formed base section formed at
a center of the earth connecting member; and a pair of retaining
pieces disposed in parallel to each other at both sides of the base
section and which are elastically deformable toward mutually inner
directions, retaining grooves which retains on the hole edge of the
penetrating hole being formed on an outer edge of each of the
retaining pieces. (7) The electronic control unit as claimed in
claim 10, wherein the elastic deformation section is formed on each
of both ends of the earth connecting member. According to the
present invention described in item (7), the elastic deformation
sections are formed on both ends of the electrical connecting
member, respectively. When the electrical connecting member is
attached onto the bus bar constituent, the respective elastic
deformation members absorb the assembly error of attaching the
electrical connecting member onto the bus bar constituent. Thus,
the assembly operation becomes facilitated.
[0111] This application is based on prior Japanese Patent
Applications No. 2011-170613 filed in Japan on Aug. 4, 2011 and No.
2011-170614 filed in Japan on Aug. 4, 2011. The entire contents of
this Japanese Patent Application No. 2011-170613 and No.
2011-170614 are hereby incorporated by reference. Although the
invention has been described above by reference to certain
embodiments of the invention, the invention is not limited to the
embodiment described above. Modifications and variations of the
embodiments described above will occur to those skilled in the art
in light of the above teachings. The scope of the invention is
defined with reference to the following claims.
* * * * *