Abstract:
A connector that includes a male connector assembly having a nose portion that removably fits within an axial cavity in a female connector assembly and which has removable, replaceable contacts. The connector assemblies are constructed for attachment to equipment and instrumentation in wet or dry environments. Each connector assembly may include a plurality of conductors that are constructed for attachment to conductors in the equipment and instrumentation. Each conductor in the male connector assembly is matched with a conductor in the female connector assembly for transmission of a signal therethrough. Electrical contacts within the connector assemblies provide individual contact of the matching conductors. Insulators separate and insulate the electrical contacts from one another.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     Not Applicable.  
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
       [0002]     Not Applicable.  
       BACKGROUND OF THE INVENTION  
       [0003]     Field of the Invention. The present invention relates to contacts for rotary connectors. Specifically, this invention relates to removable and replaceable contacts for electrical connectors.  
         [0004]     Description of the Related Art. Connector systems that either maintain electrical continuity while a first connector member may be rotatable with respect to a second connector member or allow for rotation while engaging or disengaging of connector members are useful in down hole assembly applications. In operation it is known a circular contact may be employed about or within a connector member to contact a mating member having a non-circular contact. Non-circular contacts may be conducting surfaces coaxial to the connector members inner diameter or surfaces creating a depression coaxial to the mating member.  
         [0005]     Prior art connectors often use a circular contact around the outer surface of the male connector rod or probe and a circular contact around the interior surface of the receiver or female connector to transfer a signal through the connector. An example of such a contact is U.S. Pat. No. 5,389,003 issued to Van Steenwyk et al. on Feb. 14, 1995, which discloses a wireline wet connection between receivers and probes. A conducting ring consists of a bow spring element wrapped about a conductive cylinder and bowed outwardly to make positive pressure electrical contact with a contact ring embedded in the insulative body, and a conductive inner spring element captive within the inner diameter of the receiver.  
         [0006]     U.S. Pat. No. 5,468,153 issued to Brown et al. on Nov. 21, 1995, discloses a rotatable electrical connector. A mandrel includes an enlarged hollow cylindrical head with circumferential grooves into which beryllium copper wiper springs are mounted so as to contact the interior of the housing. A brass head also has two circumferential grooves into which beryllium copper wiper springs are mounted. Continuous electric contact on the “hot wire” of the wireline is maintained between a rotor and stator through the beryllium copper wiper springs which continuously provide approximately  100  or more electrical contact points between the mating surfaces. Continuous electric contact of the “ground” is similarly maintained between the head of the mandrel and the upper housing by the beryllium copper wiper springs.  
         [0007]     U.S. Pat. No. 5,820,416 issued to Carmichael on Oct. 13, 1998, discloses a multiple contact wet connector that includes a probe assembly having a nose portion that removably fits within an axial cavity in a receiver assembly. The receiver is constructed to hold and maintain the relative longitudinal position of a circular spring contact. In an alternative embodiment, the circular spring contacts are affixed on three sides in the probe electrical contact which extends to the surface of the probe. Use of a circular spring in such a channel on a surface-exposed contact as either the receiver or probe contact are taught in claims  12  and  13  therein, respectively.  
         [0008]     U.S. Pat. No. 5,927,402 issued to Benson et al. on Jul. 27, 1999 and U.S. Pat. No. 5,967,816 issued to Sampa et al. on Oct. 19, 1999, disclose a receiver assembly having a series of receiver contacts disposed about a common axis. Each contact is machined from a single piece of electrically conductive material and has a sleeve portion with eight extending fingers. The fingers are shaped to bow radially inward, in other words to have, from sleeve portion to a distal end, a first portion that extends radially inward and a second portion that extends radially outward, forming a radially innermost portion with a contact length of about 0.150 inch. By machining contact from a single piece of stock, fingers, in their relaxed state as shown, have no residual bending stresses that tend to reduce their fatigue resistance.  
         [0009]     U.S. Pat. No. 6,439,932 issued to Ripolone on Aug. 27, 2002, discloses a multiple contact connector having a receiver and a probe. The receiver has conductor rings, or contact rings embedded in the inner surface of an insulator at predetermined unique axial spacings. The probe has contact rings embedded within its outer surface corresponding axially to the receptacle contact rings.  
         [0010]     Contacts on connecting members typically wear over time due to repeated use and may be damaged due to external objects such as impacts to the contact when exposed or due to foreign objects in or on the mating member when impact or become embedded in the connector. In such circumstances the contact may become damaged so as to no longer function. In operation such prior art has required widespread disassembly of one connecting member to replace worn contacts, which are typically embedded or integral to the connecting member. As a result, when such contacts become worn the connecting member may not be usable for some time.  
       BRIEF SUMMARY OF THE INVENTION  
       [0011]     Accordingly, it is an object of the present invention to provide an electrical contact that is replaceable.  
         [0012]     It is another object of the present invention to provide an electrical contact that may be easily and quickly replaced in the field without need for extensive disassembly.  
         [0013]     It is another object of the present invention to provide at least one electrical contact over the smallest possible distance.  
         [0014]     Other features and advantages of the invention will be apparent from the following description, the accompanying drawing and the appended claims. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]      FIG. 1  is a cross sectional view of the preferred embodiment of a probe of the rotary connector having replaceable electrical contacts, together with the alternative o-ring.  
         [0016]      FIG. 2  is a cross sectional view of the preferred embodiment of a receiver of a rotary connector, having received the probe therein, together with the alternative o-ring receiving location.  
         [0017]      FIG. 3   a  is a front view of a first embodiment of a replaceable electrical contact in a relaxed position.  
         [0018]      FIG. 3   b  is a front view of the first embodiment of a replaceable electrical contact in an expanded position.  
         [0019]      FIG. 3   c  is a front view of the alternative embodiment of a replaceable electrical contact in a compressed position.  
         [0020]      FIG. 4  is a cross sectional view of the first alternative embodiment of a probe of the rotary connector having replaceable electrical contacts, together with the alternative o-ring receiving location.  
         [0021]      FIG. 5  is a cross sectional view of the first alternative embodiment of receiver of the rotary connector, having the probe therein, together with the alternative o-ring.  
     
    
     DESCRIPTION OF THE INVENTION  
       [0022]     Referring to  FIG. 1 , the probe  20  of a rotary connector  100  having multiple replaceable contacts  9  is depicted. Replaceable contacts  9  are located about probe  20 . When rotary connector  100  is assembled, probe  20  fits snugly within receiver  60  ( FIG. 2 ).  
         [0023]     Probe  20  includes a generally cylindrical body  30 , a connector rod  40 , an insulating sleeve  19 , and one or more subsurface conductor rings  10  and insulator rings  11 . Body  30  has a body first end  31 , a body second end  32  and a body opening  33  through the length of body  30 . Body  30  is generally cylindrical about a probe axis  24 .  
         [0024]     Connector rod  40  is also cylindrical in shape and has a connector rod outer surface  41  around which insulating sleeve  19  is located. Connector rod  40  has a nose  48  on a connector rod second end  42 . Connector rod  40  and insulating sleeve  19  are retained at a connector rod first end  44  within body second end  32 . Connector rod  40  and insulating sleeve  19  extend outward from body  30  and axially coalign with probe axis  24 .  
         [0025]     A contact block assembly  2  is retained within body first end  31 . Contact block assembly  2  retains at least one pin connector  25 . Each pin connector  25  is attached to a corresponding wire  3 , each of which provides electrical continuity between a pin connector  25  and a corresponding conductor ring  10 . A ground wire  4  provides electrical continuity between a ground pin connector  43  and connector rod  40 . Wires  3  and ground wire  4  extend from pin connectors  25  and ground pin connector  43 , respectively, through body opening  33 .  
         [0026]     Conductor rings  10  and insulator rings  11  are alternately located along the outer surface of insulating sleeve  19  extending from body second end  32 . Conductor rings  10  have a conductor outer diameter  140 . Insulator rings  11  have an insulator outer diameter  150 . Conductor ring outer diameter  140  is less than insulator outer diameter  150 . A replaceable contact  9  is located about each conductor ring  10 . Because insulator outer diameter  150  is larger than conductor outer diameter  140 , replaceable contact  9  is retained between insulator rings  11  and no portion of conductor rings  10  extend to the surface of cylindrical body  30 .  
         [0027]     Referring to  FIGS. 3   a  and  3   b , when replaceable contact  9  is viewed separately from probe  20 , it can be seen that replaceable contact  9  is circular in shape, having a relaxed contact inner diameter  200  and a relaxed contact outer diameter  201 . Replaceable contact  9  is elastic, thereby providing an extended contact inner diameter  202 , which is larger than relaxed contact inner diameter  200 . The elasticity of replaceable contact  9  biases contact  9  toward a relaxed position. Thus, when placed over conductor ring  10 , replaceable contact  9  contracts towards relaxed position, although it is held in an extended position in which the biasing force creates constant contact between replaceable contact  9  and conductor ring  10 .  
         [0028]     When positioned around conductor ring  10 , extended contact outer diameter  203  is larger than insulator outer diameter  150 . Thus, when assembled, replaceable contacts  9  are raised above insulator rings  11  to provide electrical contact with receiver conductor rings  64  on receiver  60 .  
         [0029]     Replaceable contacts  9  may be canted springs. Canted spring  9  is made of a conductive metal. The diameter  301  of canted spring  300  is greater than the distance between insulator ring  11  and conductor ring  10 , respectively.  
         [0030]     At least one replaceable contact  9  is spaced along connector rod  40 . An insulator ring  11  is located between each contact  9  and serves to retain each contact  9  in a predetermined location. Insulator rings  11  and conductor rings  10  are alternately located over insulating sleeve  19  extending away from connector rod  40 .  
         [0031]     The outer diameter  150  of each insulator ring  11  is larger than the outer diameter  140  of each conductor ring  10 . Thus, a recess  50  is defined around each conductor ring  10  between adjacent insulator rings  11 , respectively. A replaceable contact  9  is placed within each recess  50 . While conductor ring  10  may be wider than replaceable contact  9  and wider than recess  50 , no portion of conductor ring  10  may have an outer diameter  140  equal to or greater than insulator outer diameter  150 . Such additional subsurface width of conductor ring  10  may thereby provide lateral contact with removable contact  9  in a shoulder or groove  120  such that conductor ring  10  has a concave outer shape. Conductor ring  10  must be less than insulator outer diameter  150  to limit the conducting surface area and thereby increase the number of contacts locatable along probe  20 .  
         [0032]     Referring to  FIG. 2 , receiver  60  is depicted with probe  20 . Receiver  60  includes a cylindrical housing  62  within which conductor rings  64  and insulator rings  66  are alternately spaced. Insulator rings  66  and conductor rings  64  have an equivalent insulator interior diameter  69 , thereby making conductor ring inner surface  67  flush with insulator ring inner surface  68 . Insulator rings  66  and conductor rings  64  are constructed to respectively be proximate to conductor ring  10  between adjacent insulator rings  11 , respectively. Interior diameter  69  of receiver  60  is greater than insulator outer diameter  150  but not greater than the combined diameter of conductor ring outer diameter  140  and diameter  301  of canted spring  300 . As a result of such difference, in operation canted spring  300  is compressed between conductor ring  10  and conductor ring  64  such that at least one point of contact exists between canted spring  300  and conductor ring  10  and at least one point of contact exists between canted spring  300  and conductor  64 , thereby completing the circuit. As a result of such points of contact, should probe  20  rotate along its connector axis with respect to receiver  60 , at least one point of contact will continue to exist.  
         [0033]     By selecting a replaceable contact  9  with a spring force coefficient sufficient to retain it about probe  20  but also sufficient to permit removal when desired, replacement of worn contacts, namely removable contract  10 , is permitted without necessity of disassembly of probe  20 . Moreover removable contact  9  may be inspected for replacement merely by removal of probe  20  from receiver  60 .  
         [0034]     In an alternative embodiment, depicted in  FIGS. 4 and 5 , receiver  60  and probe  20  may be constructed in inverse fashion. Conductor rings  10  and insulator rings  11  have equal outer diameters  140  and  150 , providing a flush surface to probe  20 . Receiver  60  would have recessed conductor rings  64 , wherein conductor ring inner surface  67  would be recessed compared to insulator ring inner surface  68 , sufficiently recessed to accept removable contact  9 . In operation such alternative embodiment requires use of additional tools to extract and replace removable contacts, unlike the preferred embodiment.  
         [0035]     In a further alternative embodiment, depicted in  FIGS. 1, 2 ,  4 , and  5 , probe  20  may have an O-ring  38  affixed about cylindrical body  30  designed to mate to a receiving location  39  within receiver  60  to provide a more rigid attachment between the two connectors and thereby retain the two connectors in relation to each other, even during relative rotation.  
         [0036]     The foregoing description of the invention illustrates a preferred embodiment thereof. Various changes may be made in the details of the illustrated construction within the scope of the appended claims without departing from the true spirit of the invention. The present invention should only be limited by the claims and their equivalents.