Information
-
Patent Grant
-
6494739
-
Patent Number
6,494,739
-
Date Filed
Wednesday, February 7, 200123 years ago
-
Date Issued
Tuesday, December 17, 200221 years ago
-
Inventors
-
Original Assignees
-
Examiners
- Bradley; P. Austin
- Hammond; Briggitte R.
Agents
- Wall Marjama & Bilinski LLP
-
CPC
-
US Classifications
Field of Search
US
- 439 369
- 439 579
- 439 445
- 439 395
- 358 473
-
International Classifications
-
Abstract
A miniature wire connector for connecting a transmission cable, defined by a plurality of coaxial cables, to an electronic imager assembly. The connector includes a substantially non-conductive supporting body, and a plurality of grooves formed in the outer surface of the body. At least a portion of each of the grooves includes a layer of conductive plating formed thereon, the grooves retaining at least an axial portion of at least one coaxial cable.
Description
FIELD OF THE INVENTION
The present invention relates to the field of coaxial cable connectors for electronic imager assemblies, and more particularly to features for relieving strain on coaxial cables that connect an electronic imager assembly to a signal processor.
BACKGROUND OF THE INVENTION
Coaxial cables have long been used to connect electrical devices to other electrical apparatus. A typical coaxial cable consists of an outer sheath enclosing a center conductor wire. The center conductor wire carries electrical signals, while the outer sheath provides electrical shielding. When such cables are used, it is well-known to provide some type of strain relief mechanism to alleviate stresses caused in the electrical connection between the coaxial cable wires and an interconnected electrical device. It is necessary that the strain relief provides adequate absorption of any pulling or twisting stresses placed on the coaxial cable wires in order to improve the reliability of the connection and prevent cable disconnection problems.
A particular field in which coaxial cables are used is that of medical or industrial imaging in which imaging devices such as endoscopes or borescopes utilize coaxial cables to connect different electrical devices with a miniature electronic imager and its associated circuitry.
For example, as shown in
FIGS. 1
,
2
, and
12
, a known video endoscopic apparatus
10
, partially shown, typically employs a plurality of coaxial cables
12
to interconnect an electronic imager assembly
20
with a signal processor
13
. The signal processor
13
receives the electrical signals produced by the electronic imager assembly
20
and processes the signals into a suitable video output signal. The signal processor
13
is connected to a video monitor
14
, a video recorder
15
, or other video peripheral device capable of handling the output video signal. The electronic imager assembly
20
shown in the FIGS. includes a miniature electronic imager
22
, such as a CCD, having a transparent window
21
disposed over the image recording surface of the imager. A set of fine pitch imager leads
24
extend from between the miniature imager
22
and the window
21
, extending to a pair of proximally located circuit boards
41
,
42
each having a plurality of electronic components
35
disposed thereupon. A transmission cable
33
includes a plurality of coaxial cables
12
which are used to transmit power to the imager assembly
20
and to transmit an electrical signal, as conditioned by some of the components
35
on the circuit boards
41
,
42
from the imager
22
.
Referring more specifically to
FIG. 12
, the imager assembly
20
is mounted in the distal end of an insertion tube or section
17
relative to a lens system which may include one or more lens elements arranged to focus a target image upon the recording surface of the imager
22
. A series of light emitting ends of a fiber bundle
16
are also disposed in proximity to the distal end of the insertion portion
17
.
A problem is that though electronic imager assemblies have been streamlined and improved, particularly in terms of miniaturization and space savings, there has been relatively little development in providing strain relief for the coaxial cables used with such assemblies. For example, and still referring to
FIGS. 1 and 2
, one method of attaching the plurality of coaxial cables
12
to an electronic imager assembly
20
is provided by solder bonding the ends of each of the center conductor wires
19
of each of the coaxial cables
12
of the transmission cable
33
to traces
34
which are provided on facing surfaces of the pair of elongated circuit boards
41
and
42
which are held in spaced relation from one another. However, in this particular arrangement, the only strain relief is provided by the traces
34
, which include only a relatively small surface area for contacting the center conductor wires
19
of the coaxial cables
12
. However, as electronic imager assemblies continue to shrink in size to meet the target demand for such devices, such forms of strain relief mechanisms have proven inadequate for a variety of reasons.
The above known form of strain relief results in a very stiff distal end since the individual conductors of each coaxial cable
12
are forced apart by a block of resin material
45
and then soldered to the traces
34
in a manner that increases the length of the stiff portion of the assembly. The above solution increases the risk of breaking the connections between the coaxial cable and the assembly when the assembly is bent, twisted or pulled. It would be desirable to decrease the length of this stiff portion, and thereby provide improved flexibility.
Another problem with the above cable interconnection technique is that overall down sizing of endoscopes, borescopes, and other medical and non-medical video inspection instruments has caused the wires of the coaxial cables to become relatively thin and tiny, making these wires even more structurally weak. Utilizing an epoxy or resin to hold these wires is ineffective since their fragility tends to either break the wires completely, or cause them to pull out of the resin when twisted or pulled. Thus, it would also be very desirable to increase the strength of the connection between the wires and the assembly.
A further problem is that available space is limited, meaning conventional means of strain relief, such as clips or interconnect arrays, are highly impractical. Simply put, there is insufficient volume, particularly within an endoscope or borescope, to accommodate such designs. Moreover, there is a general need in the field to minimize the overall size of the insertion portion of these instruments so as to provide improved patient comfort and allow access to small spaces. Thus, it would also be desirable to decrease the volume of space occupied by the wire connector and the electronic imager assembly.
Still a further problem is that the structural components of electronic imager assemblies are also relatively thin and weak. This makes the entire assembly extremely difficult to handle, particularly during assembly of the insertion tube. Thus, there is a need to provide additional structural support to the components of the imager assembly. Moreover, during assembly, there is likelihood that the imager assembly may become misaligned at any time. Even slight misalignments of the imager may render the instrument unsuitable for use. Though applying an epoxy resin in the space between the two hybrid circuit boards prevents the circuit boards from moving apart or closer together, the imager itself is still prone to being misaligned. Thus, it would also be highly desirable to prevent misalignment of the imager itself.
Yet another problem is that the connectors, such as previously described in the above referred to '313 patent, require many manufacturing steps to construct and consist of too many parts. For example, the connectors require hybrid boards that are bonded to a tapered block of resin encapsulating material.
In addition, once the endoscope is assembled, it is an extremely labor intensive, time consuming, and costly process to effect any repairs should they become necessary. As a result, a substantial need has arisen for a connector with an improved strain relief mechanism that is simple to construct and instal, and that will prevent coaxial cables from being detached or broken when placed under tension. Such a feature would vastly improve reliability and help ensure proper operation of the device.
SUMMARY OF THE INVENTION
It is therefore a primary object of the present invention to improve the state of the art of electronic imager assemblies.
It is still a further primary object of the present invention to improve the reliability of coaxial connection mechanisms for imaging instruments, such as endoscopes and borescopes.
It is yet another primary object of the subject invention to improve the integrity of the connection between coaxial cable wires and an electronic imager assembly.
According to a preferred aspect of the invention, a miniature wire connector is provided for relieving strain on coaxial cable wires electrically connected to circuit leads of an electronic imager assembly. The wire connector includes a substantially non-conductive body having a tapered construction. A plurality of grooves are formed on the body in which a layer of conductive plating is formed on at least a portion of each of the grooves. These grooves, formed in the outer surface of the non-conductive body, serve to retain at least a portion of the individual coaxial cable wires. The layer of conductive plating defines a conductive-portion, this plating layer being formed from a metallic or other electrically conductive material. Portions of the coaxial cable wires are placed within and connected to the grooves, with the center conductor wire of the cable being preferably soldered to the conductive-portion, and the conductive shield of the coaxial cable being preferably soldered to a different conductive-portion of the non-conductive body. The conductive shield may be a braided wire, serve wire, foil or plated conductive material.
The miniature wire connector may further include a recess formed in an upper or front surface of the body for fixedly retaining the electronic imager assembly. This recess includes at least one pair of substantially parallel attachment lugs used for bonding to the circuit leads of the electronic imager sensor assembly, and to fix that assembly in a stable position. The attachment lugs have at least one bonding surface for bonding to each of the hybrid circuit leads. The miniature wire connector may further include a cross-groove for providing an electrical connection to the outer sheath of the coaxial cable. The cross-groove is preferably filled with a conductive metal. The body of the wire connector may further include a fixturing hole therethrough for use during wire attachment.
The miniature wire connector is preferably used as part of a video inspection instrument, such as an endoscope or borescope. The video inspection instrument includes a tubular insertion portion capable of being positioned within a tortuous cavity, the instrument further having an optical system disposed within the insertion portion. The electronic imager assembly is disposed in relation to the optical system. According to the invention, the electronic imager assembly includes a miniature electronic imager having an image recording surface arranged to receive a focused optical signal from the optical system, a transparent window disposed over the image recording surface, and a plurality of fine pitch imager leads extending between the image recording surface and the transparent window. As noted above, the miniature wire connector is used to connect a transmission cable to the electronic imager assembly, the transmission cable including a plurality of coaxial cables. The video inspection instrument also may optionally include a plurality of electronic components for operating the miniature electronic imager, wherein at least a portion of the electronic components are substantially planarly disposed in relation to the optical system, thereby providing a compact assembly.
According to a second embodiment of the present invention, a miniature wire connector for connecting a transmission cable to an electronic imager assembly is provided.
The transmission cable is preferably the same design as that described above. In this embodiment, however, the miniature wire connector includes a substantially non-conducting center-conductor termination plate, retaining means defined in the center-conductor termination plate for retaining the electronic imager assembly on a first end surface thereof, and a plurality of grooves disposed along exterior surfaces of the center-conductor termination plate. Each of the grooves include an electrically conductive portion for retaining at least one center conductor wire of at least one individual coaxial cable, a shield termination plate, and a plurality of complementary grooves disposed along exterior surfaces of the shield termination plate for retaining a portion of a coaxial cable.
According to a third embodiment of the present invention, a miniature wire connector includes a substantially non-conducting supporting body. The wire connector, according to this embodiment, further includes retaining means defined in the supporting body for retaining an electronic imager assembly on a first end surface thereof, and a plurality of grooves disposed along exterior body surfaces for receiving at least one center conductor of at least one coaxial cable. According to this embodiment, each of the grooves has an electrically conductive portion for retaining at least a portion of at least one coaxial cable wire.
Another advantage of the present invention is that the layer of conductive plating in each groove of the described wire connector allows a large portion of the center conductor of the coaxial cable to be soldered to the conductive portion. Since more surface area of the center conductor is soldered to the groove, strain relief provided by the present connector is far superior to that of known connectors.
Yet another advantage of the present invention is that a more substantial length of the coaxial cable may be attached to the connector body.
Yet another advantage of the present invention is that the attachment lugs support and fixedly retain the sensor unit, the lugs also maintaining accurate alignment of the electronic imaging assembly.
Yet another advantage of the present invention is that the non-conductive body of the wire connector is formed using a minimum number of manufacturing and assembly steps.
Yet another advantage of the present invention is to allow for further imager assembly miniaturization.
Yet another advantage of the present invention is to allow the use of shielded and non-shielded wires.
These and other objects, features and advantages will be readily apparent from the following Detailed Description which should be read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
For a fuller understanding of the nature and objects of the invention, reference should be made to the following detailed description of a preferred mode of practicing the invention, read in connection with the accompanying drawings, in which:
FIG. 1
is a partial schematic view showing the component parts of a prior art video endoscope;
FIG. 2
is a side view of the prior art imager assembly of
FIG. 1
;
FIG. 3A
is perspective view of a wire connector having a strain relief mechanism according to a first embodiment of the present invention;
FIG. 3B
shows a variation of the wire connector of
FIG. 3A
;
FIG. 3C
is an enlarged view of the connection of the coaxial wires within the vertical grooves of the wire connector of
FIG. 3A
;
FIG. 3D
is an enlarged view of the connection of the coaxial wires within the vertical and transverse (cross) grooves of the wire connector of
FIG. 3A
;
FIG. 4
is perspective view of a wire connector having a strain relief mechanism according to a second embodiment of the present invention;
FIG. 5
is a bottom view of the wire connector shown in
FIG. 4
;
FIG. 6
is a view of the wire connector shown in
FIG. 4
;
FIG. 7
is a side view of the wire connector shown in
FIG. 4
, just prior to insertion of the cable;
FIG. 8
is a bottom view of the connector according to the second embodiment having a plurality of sockets;
FIG. 9
is a perspective view of a wire connector according to a third embodiment of the present invention;
FIG. 10
is a perspective view of the center-conductor termination plate and the shield terminator plate with the coaxial cable attached according to the third embodiment of the present invention;
FIG. 11
is a side view of the wire connector shown in
FIG. 9
with the coaxial cable attached; and
FIG. 12
is a partial enlarged side elevation of a distal end of a prior art endoscope.
DETAILED DESCRIPTION
The following description is directed mainly to several embodiments, each relating to a video endoscopic assembly. It should be readily apparent, however, that other medical and nonmedical viewing devices, such as industrial borescopes, for example, can also utilize the inventive concepts related herein. In addition, certain terminology is used throughout the course of discussion, such as “lateral”, “distal”, “proximal”, “front”, “interior”, “exterior”, “upper”, “lower” and “rear”, among others. These terms are merely used to provide a frame of reference in regard to the accompanying drawings and are not intended to be limiting of the present invention. For example, and although the following description specifically describes a wire connector having a plurality of formed grooves, it should be noted that a singular groove construction could also be employed which covers the present concept. Moreover, though the following description refers to and describes a specific coaxial cable, it should be appreciated that the inventive concepts similarly apply to other types of cables such as single conductor cables.
As described in concurrently filed and copending application Ser. No. 09/777,134, incorporated herein by reference, there is a general need to minimize the overall size of the insertion portion of a video inspection instrument in order to provide greater comfort to the patient or to allow improved access to targets whose access has been previously limited due to size limitations. To solve this problem, the above reference discloses an electronic imager assembly which includes a miniature solid state imager having an image recording surface that is arranged to receive a focused optical signal from an optical system. A transparent window is mounted in overlaying fashion over the image recording surface. A plurality of fine pitch leads extend outwardly from opposing sides of the imager from between the imager and the window. Due to the flexibility of the fine pitch leads, a number of connected electrical components permits space-saving arrangements of at least some of the components adjacent the lens cell in a distal relationship relative to the imager assembly. The above electronic imager assembly having the leads extending between the window and the image recording surface is referred to as a TAB imager assembly. An example of this form of imaging assembly is shown in
FIGS. 1 and 2
, and is also described in commonly assigned U.S. Pat. Nos. 5,754,313 and 5,734,418, each of which are herein incorporated by reference in their entirety.
This form of electronic imager assembly inspired the inventors to develop the improved miniature wire connector according to the present invention. These connectors are preferably used for connecting a transmission cable to a TAB electronic imager assembly, for example, the one depicted in
FIGS. 1 and 2
. The transmission cable includes a plurality of coaxial cables, each cable being connected by the wire connector to the electronic imager assembly. Any type of coaxial cable could be used; however, the coaxial cables
12
used in the preferred embodiment preferably including a center conductor wire
19
, an electrical insulator layer
43
disposed coaxially around the center conductor wire
19
, a layer of conductive shielding
44
coaxially surrounding the insulator layer, and an insulative jacket
48
which coaxially surrounds the conductive shielding.
Referring to
FIG. 3A
, there is illustrated a first embodiment of a one-piece miniature wire connector
60
in accordance with the present invention.
The wire connector
60
includes a substantially non-conductive body
62
having a plurality of exterior parallel grooves
64
, and a layer of conductive plating
66
formed on at least a portion of each of the grooves. The non-conductive body
62
is preferably molded as an integral or one-piece member in which the parallel grooves
64
can be created by the mold or can be later formed by grinding or other known methods. One end of the non-conductive body
62
preferably has a tapered construction which allows the individual coaxial cables
12
of the transmission cable
33
to fall along a natural path on the outside of the supporting body
62
. This arrangement reduces the stiffness of the entire assembly which results in less strain on the cables and helps prevent them from breaking during use.
The grooves
64
extend along a portion of the length of the supporting body
62
, though depending on the application the grooves may alternately other or the entirety thereof, the grooves serving to retain at least an axial portion of the individual coaxial cable wires. Preferably, the coaxial cables
12
lie within the groove
64
such that a corresponding cable is at least partially embedded in the non-conductive body
62
. The layer of conductive plating
66
defines a conductive-portion, the layer being preferably formed from a metallic material, although any known electric conductor could be utilized. One purpose of the conductive plating layer
66
is to provide a connection that carries an electrical signal between the coaxial cable wire
12
and the hybrid leads of the imager assembly. Another purpose of the conductive plating layer
66
preferably takes the form of a printed circuit that electrically connects the respective conductive shields. The above-described layer
66
also provides a large bonding surface for the solder used to join the coaxial cables to the conductive portion of the supporting body
62
of the wire connector
60
. A pair of cross grooves
68
(only one of which is shown in
FIGS. 3A
,
3
C and
3
D) extend transversely at the proximal end of the grooves
64
. These cross grooves
68
may have a conductive layer
66
also, but vertical grooves and cross grooves do not have connecting conductive layers unless it is desired.
The miniature wire connector
60
preferably includes a recess
79
formed in an upper surface of the supporting body
62
for fixedly retaining an electronic imager assembly
70
relative to the upper surface of the body. The electronic imager assembly
70
shown herein includes a cubic supporting block
72
comprising circuit boards
73
, some of each of which include electronic components (not shown) disposed on exterior surfaces thereof. Additional details relating to the electronic imager assembly are provided in commonly assigned U.S. Ser. No. 09/777,134 previously incorporated by reference.
This recess
79
is preferably defined by at least one pair of substantially parallel attachment lugs
74
, each of which of each includes interior facing bonding surfaces
76
used for bonding to the hybrid circuit leads
75
of the imager assembly
70
. These bonding surfaces
76
are preferably formed as printed circuits. The grooves
66
extend upwardly along the outer surface of the supporting body
62
and terminate at the pair of attachment lugs
74
. The interior facing bonding surfaces
76
thus provide an electrical path between the grooves
66
and hybrid circuitry (such as an amplifier) located on the circuit boards
73
of the imager assembly
70
. The interior facing bonding surfaces
76
also serve to hold the imager assembly
70
in position by attachment to the hybrid circuit leads
75
. In the meantime, fine pitch imager leads
24
extending from between the imager and transparent window are also attached to the circuit boards
73
of the mounting block
72
. The recess
79
is sized to be substantially identical in shape to the imager assembly
70
, thereby allowing the attachment lugs
74
to securely fix the imager assembly in position and even further prevent movement of the imager assembly. Similarly, it should be realized that the recess
79
can define any geometrical shape useful for securely fixing the imager assembly
70
in position. Securely anchoring the imager assembly
70
is critical in order to maintain focus of the imaging instrument.
A variation of the wire connector
80
having a non-conductive supporting body
81
is shown in FIG.
3
B. For the sake of clarity, similar parts are herein labeled with the same reference numerals. More particularly and according to this version, the body
81
includes a plurality of exterior grooves
82
, each of the exterior grooves according to this embodiment including a transverse separating cross-groove
86
. Using this construction, the exterior grooves
82
are therefore separated into two regions, namely, upper groove regions
90
which are attached to the center conductor wires, and lower groove regions
94
used for attaching a ground braid of each coaxial cable. Alternatively, the cross-groove
86
can be filled with a conductor to form a grounding bus which is used to ground the conductive grounding braid of the coaxial cable (not shown in this
FIG. 3B
, but clearly shown in
FIGS. 3A and 3C
with regard to the wire connector
60
).
Referring to
FIGS. 3A and 3B
, each of the non-conducting supporting bodies
60
,
80
may further include a lateral fixturing hole
98
extending through the entirety of the body for use during wire attachment. This lateral fixturing hole
98
serves a variety of functions, including storage of electrical components or alternate use in conjunction with a fixturing pin (not shown) to provide anchoring of the supporting body within the insertion portion of a videoized instrument.
In operation, and referring to
FIGS. 3A and 3C
, part of the insulating jacket
48
of the coaxial cable
12
is stripped away to expose the individual conductive shield
44
. The insulative jacket
48
tightly holds the individual conductive shield
44
together. Portions of the coaxial cables
12
are then placed within and connected to the grooves
64
. As discussed above, the center conductor wire
19
of each cable
12
is preferably soldered to the conductive-portion
66
, while the insulative jacket
48
is preferably attached to the non-conductive portion of the outer surface of the supporting body
62
. By soldering the center conductor wire
19
to the conductive- portion
66
of the wire connector
60
, a greater surface area of the center conductor wire
19
is soldered.
When attached, the center conductor wire
19
of each coaxial cable
12
extends slightly past the end of the supporting body
60
, and may also be soldered to the adjacent hybrid leads
75
to connect the leads to a signal processing portion of the unit. The hybrid circuitry typically includes amplifiers that drive the image signals along the transmission cable
33
to the signal processing portion. If necessary, however, the conductive shield
44
can also be soldered to the transverse cross groove
68
which serves as a grounding bus for each of the conductive shielding portions, as shown in FIG.
3
D.
As previously noted, this embodiment of the present invention is advantageous in that a one-piece conductive portion has a layer of conductive plating along each groove
64
to allow the center conductor wire
19
to be soldered to the conductive portion
66
. Soldering the wires
19
provides strain relief far superior to that of known connectors. Moreover, the imager assembly
70
is fully retained by the wire connector
60
. The attachment lugs
74
of the supporting body
62
of the described wire connector
60
maintain accurate alignment of the imager assembly
70
. Moreover and as noted above, the tapered design of the supporting body
62
allows each individual coaxial cable
12
to fall along the outer surface of the supporting body more naturally. Because the grooves
64
allow each entire coaxial cable
12
to rest within the outer surface of the supporting body
62
, and further because the imager assembly
70
is disposed on part of the supporting body
62
, the region where the center conductor wire
19
connects to the imager, the assembly is less stiff and therefore, has greater flexibility. The design also helps to prevent the center conductor wire
19
from becoming detached or separated, and strain placed on the coaxial cables
12
is substantially relieved. At the same time by tapering one end of the supporting body
62
, the stiffness of each coaxial cable
12
is substantially reduced. As a result, any coaxial cable connections are less likely to break while the attached imager assembly
70
is less likely to shift or become misaligned.
Referring to
FIGS. 4-8
, there is illustrated a second embodiment of a miniature wire connector
108
in accordance with the present invention. According to this embodiment, the miniature wire connector
108
includes a substantially non-conducting supporting body
112
, the body having retaining means
116
for retaining an electronic imager assembly on a first end surface
122
thereof, and a plurality of exteriorly disposed grooves
124
extending along exterior surfaces
128
of the body. Each of the grooves
124
have an electrically conductive portion
132
for retaining at least a portion of at least one coaxial cable wire.
The tapered, substantially non-conducting supporting body
112
includes at least one socket
136
for receiving at least one center conductor of a coaxial cable, and preferably includes a plurality of sockets
138
as shown in
FIGS. 4
,
5
, and
8
. The retaining means
116
advantageously allows for axial adjustment of a lens cell with respect to the first end surface to focus the imager. The socket
136
can be any known means for connecting or terminating a coaxial cable. As shown in
FIG. 8
, a similar connector may also include a socket
138
for each center conductor. The sockets
138
can further include a locking or retaining mechanism for attachment to the outer sheath or conductive shielding of the coaxial cable to help ensure that the center conductor remains connected within the socket.
Referring to
FIGS. 9-11
, a third embodiment of a miniature wire connector
140
includes a substantially non-conducting center-conductor termination plate
144
, and retaining means
148
defined on exterior edges of the plate
144
for retaining an electronic imager assembly
150
thereon. A plurality of grooves
152
are disposed along the exterior surfaces of the center-conductor termination plate
144
. Each of the grooves
152
have an electrically conductive portion
156
for retaining at least one center conductor wire of at least one individual coaxial cable.
A shield termination plate
160
having a plurality of adjacent grooves
164
disposed along exterior surfaces
168
retains an axial portion of a corresponding coaxial cable. The plurality of adjacent grooves
164
each retain the outer sheath of the coaxial cables in the connector. An insulating spacer plate
170
may optionally be positioned between the substantially non-conducting center-conductor termination plate
144
and the shield termination plate
160
. As shown in
FIGS. 10 and 11
, each of the adjacent grooves
164
may have an electrically conductive portion
174
for grounding the conductive shielding of the cable. Each of the adjacent grooves
164
may be electrically connected to ground via a grounding pin
172
connected between the substantially non-conducting center-conductor termination plate
144
and the shield termination plate
160
. A surface
164
of the shield termination plate
160
has at least one grounding bus
168
thereon for terminating the conductive shielding
44
. This grounding bus
168
is preferably printed on the shield termination plate
160
as a printed circuit, which electrically connects the conductive shield
44
of each coaxial cable.
Part List for FIGS.
1
-
12
10
video endoscopic apparatus
12
coaxial cables
13
signal processor
14
video monitor
16
fiber bundle
15
video recorder
17
insertion tube or section
18
lens system
19
center conductor wires
20
electronic imager assembly
21
transparent window
22
miniature imager
24
imager leads
31
protective strip
33
transmission cable
34
traces
35
electronic circuit components
41
circuit board
42
circuit board
43
insulator layer
44
conductive shield
45
epoxy block
48
insulative jacket
60
wire connector
62
supporting body
64
grooves
66
conductive layer
68
cross groove
70
imager assembly
72
cubic supporting block
73
circuit boards
74
attachment lugs
75
hybrid leads
76
bonding surfaces
79
recess
80
wire connector
81
supporting body
82
grooves
84
recess
86
cross-groove
90
upper groove regions
94
lower groove regions
98
lateral fixturing hole
108
miniature wire connector
112
supporting body
116
retaining means
120
imager assembly
122
first end surface
124
grooves
128
exterior surfaces
132
conductive portion
136
socket
138
socket
140
miniature wire connector
144
termination plate
148
retaining means
150
imager assembly
152
grooves
156
conductive portion
160
shield termination plate
164
adjacent grooves
168
exterior surfaces
170
insulating spacer plate
172
grounding pin
174
conductive portion
While the present invention has been particularly shown and described with reference to the preferred mode as illustrated in the drawings, it will be understood by one skilled in the art various changes in detail may be effected therein without departing from the spirit and scope of the invention as defined by the claims.
Claims
- 1. In combination, a wire connector connecting a plurality of coaxial cables to an imager assembly, each coaxial cable comprising a center conductor wire, and an insulative jacket coaxially aligned around the conductor wire, the wire connector comprising:a substantially non-conductive supporting body; and a plurality of grooves formed in an outer surface of the supporting body, the grooves retaining at least an axial portion of a coaxial cable, wherein at least a portion of each groove includes a conductive-plating layer, said supporting body including a recess formed in one surface of the supporting body that supports the imager assembly, said recess including at least one pair of substantially parallel attachment lugs for bonding circuit leads from the imager assembly and for fixedly retaining said imager assembly therein.
- 2. The combination as recited in claim 1, wherein the supporting body includes a through fixturing hole.
- 3. The combination as recited in claim 1, wherein the layer of conductive plating is metallic.
- 4. The combination as recited in claim 1, wherein the substantially parallel attachment lugs have at least one bonding surface for bonding to the circuit leads of the imager assembly.
- 5. The combination as recited in claim 1, wherein the center conductor wire is soldered to both the conductive plating layer and the circuit leads of the imager assembly.
- 6. The combination as recited in claim 5, further including a transverse groove for grounding conductive shielding coaxially disposed and surrounding the insulator layer which surrounds the center conductor wire.
- 7. The combination as recited in claim 6, wherein the transverse groove is filled with a conductive material.
- 8. The combination as recited in claim 7, wherein the conductive shielding is soldered to the transverse groove.
- 9. A video inspection instrument comprising:a tubular insertion portion capable of being positioned within a tortuous cavity; an optical system disposed within the insertion portion; an imager assembly disposed in relation to the optical system, said imager assembly including a miniature electronic imager having an image recording surface arranged to receive a focused optical signal from the optical system, a transparent window disposed over the image recording surface, and a plurality of fine pitch leads extending between the image recording surface and the transparent window; a miniature wire connector for connecting a transmission cable to the imager assembly, the transmission cable comprising a plurality of coaxial cables, each of the coaxial cables including a center conductor wire, an electrical insulator coaxially disposed around the center conductor wire, conductive shielding coaxially surrounding the electrical insulator, and an insulative jacket coaxially surrounding the conductive shielding, the wire connector comprising a substantially non-conductive supporting body, a plurality of grooves formed in the outer surface of the supporting body, the grooves retaining at least an axial portion of at least one coaxial cable wire, wherein at least a portion of each of the grooves includes a formed layer of conductive plating and a recess formed in an upper surface of the supporting body, the recess being formed on a distal surface of the supporting body and including at least one pair of substantially parallel attachment lugs for fixedly retaining the imager assembly within said recess; and a plurality of electronic components for operating the miniature electronic imager, wherein at least a portion of the electronic components are substantially planarly disposed in relation to the optical system, thereby providing a compact assembly.
- 10. In combination, a wire connector providing strain relief to at least one transmission cable interconnected to a TAB imager assembly, the at least one transmission cable comprising a plurality of coaxial cables, the coaxial cables each comprising a center conductor wire, an electrical insulator around the center conductor wire, conductive shielding surrounding the insulator, and an insulative jacket around the braiding , the connector comprising:a substantially non-conducting supporting body; a recess defined in the supporting body fixedly retaining said imager assembly on a first end surface thereof; and a plurality of grooves disposed along exterior surfaces of the supporting body, each of the grooves having an electrically conductive portion that retain at least a portion of at least one coaxial cable wire.
- 11. The combination as recited in claim 10, wherein the substantially non-conducting supporting body includes at least one socket for receiving at least one center conductor of at least one coaxial cable.
- 12. The combination as recited in claim 11, wherein the substantially non-conducting supporting body includes a plurality of sockets.
- 13. The combination as recited in claim 12, wherein the retaining means allows axial adjustment of a lens cell with respect to the first end surface relative to the imaging assembly.
- 14. A miniature wire connector connecting a transmission cable to a TAB imager assembly, the transmission cable comprising a plurality of coaxial cables, the coaxial cables each comprising a center conductor wire, an electrical insulator around the center conductor wire, conductive shielding surrounding the insulator, and an insulative jacket around the braiding, the connector comprising:a substantially non-conducting center-conductor termination plate; retaining means defined in the center-conductor termination plate for retaining said TAB imager assembly; a plurality of grooves disposed along exterior surfaces of the center-conductor termination plate, each of the grooves having an electrically conductive portion for retaining at least one center conductor wire of at least one individual coaxial cable; a shield termination plate adjacent to said center-conductor termination plate; and a plurality of adjacent grooves disposed along exterior surfaces of the shield termination plate for retaining a portion of the at least one coaxial cable.
- 15. The miniature wire connector as recited in claim 14, further comprising an insulating spacer plate positioned between the substantially non-conducting center-conductor termination plate and the shield termination plate.
- 16. The miniature wire connector as recited in claim 14, each of the adjacent grooves having an electrically conductive portion for retaining at least a portion of at least one conductive shielding, each of the adjacent grooves being electrically connected to a ground via a grounding pin connected between the substantially non-conducting center-conductor termination plate and the shield termination plate.
- 17. The miniature wire connector as recited in claim 16, wherein a surface of the shield termination plate has at least one grounding bus thereon for terminating the conductive shielding of the coaxial cables.
- 18. A videoized instrument system comprising:a video instrument having an insertion portion capable of placement within a cavity; a lens system mounted in the distal end of the insertion portion; a fiber optic bundle having a plurality of light emitting ends disposed in proximity to the distal end of the insertion portion, said lens system being arranged for focusing an image of a target onto an imager assembly, said imager assembly including: a transparent window mounted over a miniature video imaging element, a first set of imager leads passing outwardly from between the miniature video imaging element and the transparent window to one side of the package and a second set of imager leads passing outwardly from between the miniature video imaging element and the window to the other side of the unit; a miniature wire connector for connecting a transmission cable to said imager assembly, the transmission cable comprising a plurality of coaxial cables, each coaxial cable comprising a center conductor wire, an electrical insulator around the center conductor wire, conductive shielding surrounding the insulator, and an insulative jacket around the shielding, the wire connector comprising a substantially non-conductive supporting body, a plurality of grooves formed in the outer surface of the body, the grooves retaining at least an axial portion of at least one coaxial cable wire, wherein at least a portion of each of the grooves includes a layer of conductive plating formed thereon, and a recess formed in an upper surface of the supporting body, the recess being formed on a distal surface of the supporting body and including at least one pair of substantially parallel attachment lugs for fixedly retaining the imager package within said recess; and supporting means for supporting at least some of the electronic components within the insertion portion.
US Referenced Citations (24)