WO2016134024A1

WO2016134024A1 - Pcb frame assembly and method of assembly

Info

Publication number: WO2016134024A1
Application number: PCT/US2016/018278
Authority: WO
Inventors: Scott Anthony FAULKNER
Original assignee: Phoenix Contact Development and Manufacturing, Inc.
Priority date: 2015-02-17
Filing date: 2016-02-17
Publication date: 2016-08-25

Abstract

A printed circuit board frame assembly includes a populated printed circuit board and a frame having a shroud that covers a portion of the printed circuit board when the printed circuit board is held in the frame. The printed circuit board is attached to the frame by inserting the printed circuit board into an opening of the frame and rotating the frame to move the portion of the printed circuit board underneath the shroud.

Description

PCB FRAME ASSEMBLY AND METHOD OF ASSEMBLY Related Application

This application claims priority from co-pending US Provisional Patent Application No. 62/117,118 titled "Terminal Block Housing" filed 17 February 2015 at Attorney Docket No. 14-1329-P, which priority application is incorporated by reference as if fully set forth herein.

Field of the Disclosure

This disclosure relates to printed circuit boards, and in particular, to a PCB frame assembly for mounting a printed circuit board within a frame, and the method of assembling the PCB frame assembly.

Background of the Disclosure

A known printed circuit board (PCB) frame assembly includes a rectangular- shaped PCB mounted in a frame. The frame surrounds the sides and ends of the PCB and includes mounting structure formed as tabs that attaches the PCB assembly onto a base for use.

The PCB has electrical components mounted on the top surface of the PCB. A terminal block is mounted to a front section of the PCB and a pair of modular connectors formed as conventional DIN headers are mounted to a back section of the PCB. The terminal block has a single-piece housing that contains electrical terminals. The terminals include terminal pins that extend from the housing and are closely received in through-holes in the PCB to form electrical connections between the electrical terminals and the DIN headers. The terminal pins are soldered to the PCB to assure dependable electrical connections.

The frame is manufactured integral with the terminal block housing. When the terminal block is placed on the PCB, the PCB is also received within the frame. The frame includes a pair of side walls that extend along the sides of the PCB, a pair of end walls that extend along the ends of the PCB, and a shroud that covers the top of the back section of the circuit board. The shroud includes openings that receive the DIN headers and other electrical components, exposing them for use. The end walls extend downwardly past the PCB and carry the tabs. The tabs are received in slots formed in the base to secure the PCB frame assembly to the base.

The terminal block housing has side walls that form portions of the frame side walls. The housing side walls are spaced apart by more than the width of the PCB. This enables the PCB holes to be distributed substantially along the full width of the PCB and in turn enables the structural components of the electrical terminals to be made as large and as strong as possible.

The terminal block housing and shroud closely cover the top of the PCB after the terminal block has been soldered to the PCB. This prevents applying a conformal coating to the top surface of the PCB. A conformal coating is a conventional thin protective coating or film typically sprayed on the PCB to provide environmental and mechanical protection of the PCB circuits and components.

Furthermore, the end walls of the frame prevent or complicate conventional use of a solder bath to solder the terminal pins or to solder additional components to the PCB after the terminal block has been placed on the PCB. The end walls would extend into the solder bath during the bath soldering process.

Brief Summary of the Disclosure

Disclosed is an improved PCB frame assembly that enables applying a conformal coating to the top surface of the PCB after the terminal block has been soldered to the PCB, and enables additional components to be soldered to the circuit board after soldering of the terminal block using a conventional solder bath.

The disclosed PCB assembly includes a PCB, a frame that includes a shroud or cover that covers a portion of the PCB when the PCB is in the frame, and a terminal block that is a separate component not integral with the frame (that is, in embodiments the terminal block and the frame are detachably connectable to one another) . The PCB is unchanged from the PCB described above for the known PCB assembly. The terminal block remains wider than the PCB so that the structural components of the electrical terminals remain as large and as strong as possible.

The terminal block is soldered to the front section of the PCB board before the PCB is inserted into the frame. This enables applying a conformal coating to the top surface of the PCB before the surface is covered by the shroud.

In an embodiment at least a portion of the terminal block housing is spaced above the entire width of the PCB after the terminal block is soldered to the PCB. This exposes a portion of the PCB under the terminal block and enables access from one or both sides of the PCB for applying a conformal coating to the exposed surface of the PCB .

When the PCB carrying the terminal block is inserted into the frame, the side walls of the frame are flush with the side walls of the terminal block. The frame side walls extend upwardly beyond the PCB to close the ends of the gap between the terminal block and PCB.

Because the frame side walls are flush with the terminal block side walls, the PCB cannot be simply inserted into the frame from either the upper or lower side of the frame. Inserting the PCB board into the frame from the upper side of the frame is obstructed by the shroud. Inserting the PCB board into the frame from the lower side of the frame is obstructed by the terminal block.

This disclosure includes a method for inserting the PCB into the frame.

The back section of the PCB is narrower than the distance between the frame side walls. This enables the back section of the PCB to be inserted into the frame between the frame sidewalls away from the shroud. The PCB is positioned over the frame essentially perpendicular to the frame, with the back section of the PCB adjacent to the frame and the PCB top surface facing towards the shroud. The back section of the PCB is inserted into the frame in the open area of the frame between the frame sidewalls away from the shroud.

The back end of the PCB is inserted into the frame while the PCB is maintained perpendicular to the frame until the terminal block reaches the frame sidewalls and prevents further insertion of the PCB. The PCB is then rotated with respect to the frame to place the PCB into the frame. Rotation continues until the PCB back section is received into the shroud and the terminal block side walls are placed on top of the frame side walls. The frame side walls of the frame are then flush with the terminal side walls. The frame side walls essentially close the ends of any gap between the terminal block and the PCB.

In a disclosed embodiment the frame includes anti- rotation structure that engages the PCB after the PCB has rotated into the frame. The anti-rotation structure in an embodiment is a projecting tab that moves over the PCB and resists rotation of the PCB that would separate the PCB from the frame.

In a further embodiment the frame and the assembled PCB includes cooperating guide structure that cooperate with one another when inserting the PCB into the frame.

In an embodiment the cooperating guide structure includes indentations on both terminal block sidewalls that define inclined guide surfaces on both sides of the terminal block that extend to the back end of the terminal block. The terminal block between the indentations has a narrower width than the remainder of the terminal block.

The cooperating guide structure on the frame includes features on both side walls. The frame side walls are spaced apart a distance less than the narrower wider portion of the terminal block so that the terminal block cannot be received between the side walls. A portion of the frame side walls adjacent the shroud, however, has a reduced wall thickness that enables the narrower portion of the terminal block to be received between that portion of the frame side walls.

Each side wall also includes a projection at the reduced wall thickness extending into the interior of the frame. The projection is shaped like a truncated trapezoid, with parallel upper and lower inclined guide surfaces. The trapezoid extends towards the front end of the frame and extends into the narrower frame portion.

The back section of the perpendicular PCB is inserted into the frame in the narrower portion of the frame until the terminal block is near or against the frame side walls. The PCB is then translated or moved laterally towards the projections until the PCB reaches the projections. This locates the PCB along the frame side walls to begin rotation of the PCB around the leading ends of the projections.

Rotation of the PCB around the leading ends of the projections continues until the top surface of the PCB is parallel with the lower projection guide surfaces. This enables the PCB to slide along the lower guide surfaces. The distance between the upper and lower projection guide surfaces is such that the projections are partially received in the gap between the terminal block and the PCB as the PCB slides along the lower guide surface.

Sliding continued until the guide surfaces on the terminal block come against the top of the frame side rails. This locates the PCB at the correct depth with respect to the frame so that continued rotation of the PCB has the back end of the PCB correctly received into the shroud and the front end of the PCB to correctly overlay the front end of the frame. The PCB rotates until the anti-rotation structure actuates to retain the PCB in the frame. In yet other possible embodiments of the disclosed PCB assembly, the PCB includes, instead of a terminal block, a different electrical component that is wider than the PCB. The electrical component includes the guide structure that cooperates with the frame guide structure to position and rotate the PCB into the frame.

In yet further possible embodiments of the disclosed PCB assembly, the guide structure attached to the PCB is not formed on an electrical structure. Instead, dedicated guide structure that extends outwardly from the sides of the PCB board is attached to the PCB board and cooperates with the frame guide structure to position and rotate the PCB into the frame .

Other objects and features of the disclosure will become apparent as the description proceeds and describes one or more illustrative embodiments.

Brief Description of the Drawings

Figures 1-3 are top, side, and front views respectively of the PCB board of the disclosed PCB assembly prior to mounting of a terminal block.

Figures 4-6 are back, right side, and front views respectively of a terminal block for mounting on the PCB board shown in Figure 1, a left side view of the terminal block being a mirror image of the right side view.

Figures 7 and 8 are perspective views of the terminal block shown in Figure 4.

Figures 9-11 are top, right side, and front views respectively of the PCB board shown in Figure 1 with the terminal block shown in Figure 4 and other electrical components soldered to the PCB board, the left side view being a mirror image of the right side view.

Figures 12-14 are top, right side, and front views of a frame of the disclosed PCB assembly.

Figure 15 is a vertical section view taken along line 15- 15 of Figure 12. Figures 16-18 are vertical section views taken along lines 16-16, 17-17, and 18-18 respectively of Figure 12.

Figures 19-21 illustrate respective steps of inserting the PCB shown in Figure 9 into the frame shown in Figure 12.

Figures 22-26 are sectional views illustrating the respective steps of inserting the frame shown in Figure 9 into the frame shown in Figure 12.

Detailed Description

The illustrated embodiment of the disclosed PCB assembly includes a PCB, a terminal block mounted on the PCB, and a frame that receives the PCB. Figures 1-3 illustrate the PCB prior to attachment of the terminal block. Figures 4-8 illustrate the terminal block prior to attachment to the PCB. Figures 9-14 illustrate the frame prior to insertion of the PCB .

A PCB 10 is shown in Figures 1-3 partially populated, that is, prior to attachment of the terminal block. The PCB 10 is a generally flat, rectangular board 12 having a top surface 14 and an opposite bottom surface 16 separated by the thickness of the board. The board 12 extends from a front end 18 to a back end 20 spaced apart by the length of the board. The board 12 includes a left side 22 and an opposite right side 24, the sides separated by the width of the board. Rows 26 of through-holes 28 are located in a front section 30 of the board adjacent the board front end 18. The rows of through holes include a front-most row 26a and back rows 26b, 26c, 26d. The through-holes 28 are spaced apart in each row essentially the full width of the board. A pair of conventional DIN headers 32a, 32b are attached to the top surface of the board in a back section 34 of the board adjacent the back end of the board.

Figures 4-8 illustrate a terminal block 40 prior to attachment to the PCB 10. To simplify the drawings, Figures 7 and 8 show the terminal block without electrical terminals. The terminal block 40 includes a single-piece housing 42 that contains sets of electrical terminals 44. The electrical terminals 44 are arranged in a conventional "staircase" arrangement with the lowest "step" located at the front end of the PCB when the terminal block is attached to the PCB. Terminal blocks having other conventional terminal arrangements are known and can be adapted for use with the disclosed PCB frame assembly. Each electrical terminal 44 includes a downwardly extending terminal pin 46 that extends out of the housing 42. The electrical terminals 44 are arranged in the housing 42 in stacked rows, including a front- most row 48a and back rows 48b, 48c, 48d. The rows 48 of terminals are arranged so that the terminal pins are received in corresponding rows of holes of the PCB. This arrangement is conventional and so will not be described in detail.

The terminal block housing 42 includes a pair of flat, generally parallel side walls 50, 52 spaced apart the maximum width of the terminal block, and a back wall 54 extending between the side walls. The width of the terminal block housing between the side walls 50, 52 is greater than the width of the PCB 10. The terminal block walls may be designed with a taper or draft for ejection or removal from a mold.

The side walls 50, 52 and the back wall 54 extend downwardly from a top side 56 of the housing 42 towards a bottom side 58 of the housing. The bottom side 58 of the housing 42 has a width equal to the width of the PCB 10.

The portion of the terminal block housing 42 containing the front-most row 48a of terminals extends from the top side of the housing to a front bottom wall surface 60 to house the terminals 44. The pins of the front-most row 48a of terminals extend out from the front bottom wall surface 60.

A bottom wall section 62 forming part of the bottom side of the terminal block housing 42 away from the front bottom wall surface 60 is recessed upwardly from the bottom wall surface 60 towards the top side 56. This defines a recess or volume 64 above the horizontal plane defined by the bottom wall surface 60 that is the width of the PCB 10. The pins of the back rows 48b, 48c, 48d of terminals extend out of the bottom wall section 62 and into the recess 64. Each pin of the back rows of terminal pins include a wider width section 66 located in the recess 64 that is larger than its associated PCB hole 28 and a reduced width section 68 extending out of the recess 58 sized to be received in the PCB hole 28.

The terminal block housing 42defines a pair of flat, parallel outer wall surfaces 70, 72 that extend above the recess 64. The wall surfaces 70, 72 are recessed inwardly with respect to the side walls 50, 52. The wall surfaces 70, 72 are spaced apart the same distance as the width of the PCB 10 and extend up to the side walls 50, 52 respectively. The transition from the wall surfaces 70, 72 to the side walls 50. 52 is defined by the downward facing surfaces 74, 76, each surface 74, 76 extending in a straight line above the recess 64 and to the back side 54 of the housing 42

As will be described in further detail below, the tops of the frame side rails are positioned just under the surfaces 74, 76 to effectively close the opposite ends of the recess 64 when the PCB 10 is held in the frame.

A portion of the housing 42 behind the rearmost row of terminals 48d extends to a back bottom wall surface 78 that is flush with (that is, co-planar with) the front bottom wall surface 60. The surfaces 60, 78 assist in supporting the terminal block 40 against the PCB top surface 14 when the terminal block is attached to the PCB.

Openings 80 are spaced along the front of the housing 42 each extend upwardly from the bottom wall surface 60 and extend to each pin of the front-most row 48 of terminals.

The terminal housing 42 further includes guide structure that cooperates with guide structure on the frame to position and move the PCB into the frame as will be described in more detail later below. The terminal housing guide structure includes flat, generally triangular- shaped side wall indentations 86 formed on each of the side walls 50, 52. The indentations are located on the bottom side of the housing and extend to the back side of the housing. The indentations define a narrower width portion 88 of the housing located at the back and bottom of the housing. The narrower width is less than the maximum terminal block width defined by the housing side walls, but is greater than the width of the PCB .

Each indentation 86 is defined by a flat, outwardly facing recessed surface 90 and is bounded by a flat, straight surface 92 that extends between the recessed surface 90 and the adjacent side wall 50 or side wall 52. The surface 92 extends upwardly from the horizontal surface 74 or surface 76 to the rear side 54. Each surface 92 is inclined with respect to the horizontal at an inclination angle 94 best seen in Figure 5.

Figures 9-11 illustrate the fully populated PCB 10, that is, after attachment and soldering of the terminal block 40 to the PCB. Because the terminal block 40 does not extend beyond the bottom surface of the PCB, a conventional solder bath can be used to solder the terminal block and other electrical components to the PCB. The terminal block recess 64 provides access for conformal coating of the PCB board around the back rows of terminal pins after the terminal block is attached to the PCB. The front terminal block openings 80 provides access for conformal coating of the PCB board 10 in the vicinity of the front-most row of terminal pins

Figures 12-18 illustrate the frame 100.

The frame 100 is sized to receive and hold the populated PCB 10 shown in Figure 9. The frame 100 has an upper side 102 and a lower side 104. A pair of spaced apart left and right side walls 106, 108 and a pair of spaced apart front and back end walls 110, 112 joining the frame side walls define the generally rectangular shape of the frame. A cover or shroud 114 extends between the frame side walls from the back end wall 112 to a front end 116 spaced from the front frame end wall 110. The shroud 114 defines a covered or closed section 118 of the frame adjacent the back end wall 112, and an uncovered or open section 120 of the frame adjacent the front end wall 110.

The end walls 110, 112 each extend downwardly away from the frame side walls 106, 108 and define overhangs that will mount the frame 100 to a base in a conventional manner using tabs 122 carried by the end walls. The front end wall 110 includes alignment projections 124 that assist in preventing relative motion between the frame 100 and the PCB 10 when the PCB is held in the frame.

The shroud 114 includes through openings 126 that will receive and provide access to electrical components of the PCB 10 when the PCB is held in the frame 110. The illustrated openings 126 are configured to receive the DIN headers 32a, 32b. The front end 116 of the shroud is contoured to closely conform to the back side 54 of the terminal block housing 42.

Each frame side wall 106, 108 is a straight member that extends along a respective longitudinal axis. Each frame side wall includes a side wall section 128 extending along the open frame section 120. The side wall section 128 has a flat top 130 and a bottom 132 parallel with the top 132 spaced apart by the height of the side rail. The frame side wall section 128 has a lower portion 134 adjacent the bottom 132 and an increased-width upper portion 136 adjacent the top 130 as best seen in Figure 16. The wall thickness of the lower portion 134 is such that the frame width between the pair of lower portions 134 is greater than the width of the PCB 10 and permits the PCB to be received between them.

The wall thickness of the upper portion 136 of the side wall section is such that the frame width between the pair of upper portions 136 is greater than the width of the PCB 10 but is less than the narrower terminal block width 88 defined by the terminal block guide structure. This enables the back section 34 of the populated PCB board 10 to be inserted into the open section of the frame between the side wall sections, but the maximum width of the terminal block housing prevents insertion of the front section 30 of the PCB board into the open section of the frame.

The frame 100 includes a pair of latches 138 located near the intersections of the side rails 106, 108 with the front rail 110. Each latch 138 extends into the interior of the frame and includes a generally flat bottom surface that will overlay the top surface 14 of the PCB 10 when the PCB is held in the frame.

The side wall sections 128 of the frame side rails 106, 108 each include like guide structure that cooperates with the guide structure on the terminal block housing 42 to position and move the PCB 10 into the frame lOOas will be described in more detail later below.

The frame guide structure is located on each side wall section 128 adjacent to the shroud 114. The guide structure on the side wall section of the left side rail 106 will be described, it being understood the right side rail 108 has like guide structure.

The frame guide structure includes a reduced width section 140 (see Figure 17) of the side wall section 128 and a generally trapezoidal projection 142 (see Figures 15 and 17) extending from the side wall section 128 into the interior of the frame. The side wall projections 142 on the side rails 106, 108 face one another and each extends into the interior of the frame a distance greater than the thickness of the increased-width portion 136 of the side wall section 128. The distance between the projections 142 is less than the width of the PCB 10, that is, the width of the PCB 10 prevents the PCB from being received between the projections 142.

The reduced width rail section 140 extends from the shroud 114 towards the front end of the frame, and in the illustrated embodiment, has a greater height than the other portion of the side wall section 128. The reduced width rail section 140 eliminates the increased-width upper section 136 and, in the illustrated embodiment, is formed by making the entire wall thickness the same as the lower portion 134 of the side rail section as seen in Figure 17. The distance between the reduced width sections 140 of the left and right frame side rails is greater than the narrower terminal block width 88 defined by the terminal block guide structure but is less than the maximum width of the terminal block.

The projection 142 is spaced away from the shroud 114 and is spaced below the top 130 of the frame side rail section 128. The projection 142 has a flat upper surface 144 and a flat lower surface 146 that are each parallel with the top 130 of the side rail. The upper surface 144 is spaced towards the front end of the frame as compared to the bottom surface 146. The upper surface 144 is aligned with the bottom 132 of the increased-width portion of the side rail section 128 and extends beneath the increased-width portion of the side rail section 128. Top and bottom inclined surfaces 148, 150 respectively extend from opposite ends of the upper surface towards 144 the bottom surface 146. The inclined surfaces 148, 150 are inclined at an acute angle from the horizontal plane defined by the rail section top 130. The inclination angle of each inclined guide surface 148, 150 is equal to the inclination angle 94 of the inclined surfaces 92 of the terminal block housing guide structure.

The parallelogram defined by the four projection guide surfaces 144, 146, 148, 150 is truncated a short distance from where the surfaces 144, 150 would intersect to define an abutment surface 152 that is perpendicular to the rail axis and is perpendicular to the top 130. The parallelogram is also truncated a distance from where the guide surfaces 144, 146 would intersect. Insertion of the populated PCB 10 into the frame 100 is discussed next. The frame cannot be merely inserted over the populated PCB due to interference between the frame side rails and the terminal block.

Figures 19-21 illustrate the basic steps of inserting the populated PCB into the frame.

As shown in Figure 19, the PCB 10 is positioned over the frame 100 essentially perpendicular to the frame, that is, perpendicular with the plane defined by the tops 130 of the side rails 106, 108. The back section 34 of the PCB is closest to the frame 100 and is over the frame open section 120. The PCB top surface 14 faces towards the shroud 114. The back section 34 of the PCB is then inserted into the open frame section 120 between the projections 142 and the frame front wall 110 until the terminal block interferes with the frame rails 106, 108.

The PCB 10 is then rotated clockwise as shown in Figure 20 to move the back section 34 of the PCB towards the shroud 114 and the terminal block side walls 550, 52 move towards the tops 130 of the side wall sections. Rotation continues until the PCB 10 is inserted into the frame 100, with the PCB ending up horizontal and parallel with the side rails 106, 108.

Figure 21 illustrates the populated PCB 10 inserted into and held in the frame 100 to form a PCB frame assembly 200. Rotation of the PCB to horizontal (parallel with the frame side rails 106, 108) has moved the PCB past the frame latches 138, deforming the latches and enabling the bottoms of the latches to closely overlay the top surface 14 of the PCB. The terminal block housing 42 has openings 156 (see Figure 10) that receive the latches and enable the latches to extend over the top surface of the PCB. The latches 138 resist counterclockwise rotation of the PCB relative to the frame 100 away from the horizontal position after the PCB is inserted into the frame. The front end of the PCB 10 overlays the frame front wall 110 when the PCB 10 has reached the horizontal position. The frame alignment projections 124 are received in the openings 80 formed at the front of the terminal block housing and help resistant lateral displacement of the PCB relative to the frame .

As shown in Figure 21, the terminal block side walls 50, 52 are flush with the outermost sides of the frame side rails 106, 108 respectively. The tops 130 of the frame side rails extend along and are closely spaced from the housing surfaces 74, 76. The frame side rails 106, 108 cover both ends of the terminal block recess 64 and close the ends of the recess 64. The end 116 of the shroud 114 is closely spaced from the housing back wall 54.

Figures 22-26 illustrate in more detail insertion of the populated PCB into the frame utilizing the guide structures on the terminal block and frame.

Figure 22 illustrates the PCB 10 after the back section 34 of the PCB was been inserted into the open section 120 of the frame to the point where the terminal block 40 has engaged the frame side rails 106, 108. The PCB is slid along the frame rails to abut against the pair of projection abutment surfaces 152. The abutment surfaces 152 define the longitudinal position of the PCB along the frame side rails where rotation of the PCB away from vertical and towards horizontal should initially take place. Clockwise rotation of the PCB as shown in Figure 22 causes the PCB to rotate about the abutment surfaces 152.

Figure 23 illustrates clockwise rotation of the PCB away from the vertical position shown in Figure 22. The abutment surfaces 152 are relatively narrow and "line-like", and so the PCB essentially rotates clockwise about an axis of rotation defined essentially by the forward end of the guide surfaces 144. Figure 23 illustrates the relative position of the PCB 10 to the frame 100 at the point where the PCB is close to and parallel with the lower inclined projection surfaces 150, and the bottom surface 58 of the terminal block housing is parallel with the upper inclined projection surfaces 148. The projections 142 are sized to enable the narrower-width portion 88 of the terminal block guide structure to slide downwardly along the upper inclined surfaces 148, moving the PCB further into the frame.

Figure 24 illustrates the PCB after the narrower-width portion 88 of the terminal block housing has translated down the inclined surfaces 148 and is received between the reduced width sections 140 of the frame side rails. During translation the projections 142 are received into the gap between the PCB and the bottom surface 58 of the terminal block housing. The inclined terminal block housing surfaces 92 are parallel with the tops 130 of the side rails and move against and engage the tops 130 of the frame side rails to resist and prevent further translation of the PCB into the frame .

At this point the PCB 10 is placed in the proper position relative to the frame 100 for continued rotation of the PCB to cause the frame to properly receive and hold the PCB. The PCB now rotates clockwise about an axis of rotation defined essentially by the line defined by the intersection of the pair of projection guide surfaces 144 and projection guide surfaces 150. The DIN headers and other electrical components on the back end of the PCB are received into the corresponding shroud openings 126, and the terminal block openings 156 are correctly aligned with the frame latches 138 for the latches to move into the openings when the PCB has reached the horizontal position shown in Figure 25. The PCB is located beneath the projections 142 closely spaced from and parallel with the projection guide surfaces 146. The terminal block 40 includes a single-piece housing 42. Modular terminal blocks formed of multiple "slices" are known and can be adapted for use with the disclosed PCB frame assembly. An example of such a modular terminal block is disclosed in Correll, US Patent 7,462,063 owned by the applicant herein and incorporated by reference as if fully set forth herein.

In other embodiments of the disclosed PCB frame assembly, guide structure similar to the guide structure formed on the terminal block housing 42 can be located on other types of electrical or mechanical components attached to the front section of the PCB board. For example, in one possible embodiment a heat sink that is wider than the width of the PCB board is attached to the front section of the PCB board and includes guide structure that assists in the positioning and inserting of the PCB into the frame as described above.

In yet other embodiments of the disclosed PCB frame assembly, guide structure similar to the guide structure formed on the terminal block housing 42 can be realized as separate mechanical components that are attached to the front section of the PCB to assist in the positioning and inserting of the PCB into the frame as described above.

Features of the disclosed frame assembly may include the following features, alone or in combination:

1. A printed circuit board frame assembly comprising: a printed circuit board (PCB) , the PCB comprising spaced apart opposite first and second ends separated by a length of the PCB, first and second sides spaced apart by a width of the PCB, and upper and lower sides separated by a thickness of the PCB, a first portion of the PCB located at the first end and a second portion of the PCB located at the second end, the second portion of the PCB carrying a pair of overhanging component portions on the upper side of the PCB that extend outwardly beyond the first and second sides of the PCB; a frame not integrally formed with the PCB or components carried on the PCB, the frame comprising spaced apart first and second end walls, first and second spaced apart rails joining the first and second end walls, a shroud extending between the first and second rails, the shroud comprising a first end spaced away from the first end wall, the first end wall, the rails, and the end of the shroud defining a through opening in the frame, the side rails defining a width of the frame opening;

the width of the PCB being less than the width of the frame opening, the first end of the PCB being insertable into the frame opening to place the PCB in a first assembly position with respect to the frame wherein the first end portion of the PCB is in the frame opening with the top surface of the PCB facing towards the second end wall, the overhanging component portions of the PCB interferable with the frame side rails to resist further insertion of the PCB into the frame opening;

the PCB rotatable from the first assembly position to an inserted position with respect to the frame wherein the first end portion of the PCB rotates towards the shroud and the second end portion of the PCB rotates towards the frame side rails, the top surface of the first end portion of the PCB being at least partially covered by the shroud and the overhanging components of the PCB against the side rails when the PCB is in the inserted position.

2. The PCB frame assembly of feature 1 wherein the frame includes at least one latch that extend over the PCB after the PCB has moved from the first assembly position to the installed position, each latch resisting rotation of the PCB from the installed position towards the first assembly position .

3. The PCB frame assembly of feature 1 wherein the PCB is movable in the opening along the frame side rails when the PCB is in the first assembly position with respect to the frame, the frame comprising an abutment surface spaced from the shroud that limits such movement of the PCB towards the shroud .

4. The PCB frame assembly of feature 3 wherein the PCB is placed against the abutment surface to place the PCB in the first assembly position, the PCB rotatable about the abutment surface to initiate movement of the PCB from the first assembly position towards the second assembly position.

5. The PCB frame assembly of feature 4 wherein the PCB is rotatable about the abutment surface from the first assembly position to a second assembly position wherein the sides of the PCB are inclined with respect to the frame side rails, the frame comprising a first guide surface parallel with the sides of the PCB when the PCB reaches the second assembly position, the PCB translatable along the first guide surface from the second assembly position to a third assembly position wherein the relative positions of the first and second PCB portions with respect to the frame are thereby established .

6. The PCB frame assembly of feature 5 wherein the PCB is rotatable from the third assembly position to the installed position .

7. The PCB frame assembly of feature 6 wherein the frame comprises a second surface adjacent the PCB when the PCB is in the third assembly position with respect to the frame, the PCB rotatable about the second surface as the PCB translates from the second assembly position to the third assembly position.

8. The PCB frame assembly of feature 7 wherein the second surface forms a portion of a second guide surface parallel with the first guide surface.

9. The PCB frame assembly of feature 8 wherein the first and second guide surfaces are formed on a generally trapezoidally- shaped projection extending from one or both of the frame side walls into the frame opening. 10. The PCB frame assembly of feature 4 wherein each frame side rail comprises a reduced-wall thickness section that receives the PCB when the PCB translates from the second assembly position to the first assembly position.

11. The PCB frame assembly of feature 4 wherein the overhanging components of the PCB define a narrower width portion of said overhanging components, the narrower width portion of said components being received between the reduced- wall thickness sections of the frame side rails when the PCB translates from the second assembly position to the third assembly position.

12. The PCB frame assembly of feature 11 wherein the overhanging component portions of the PCB define a pair of spaced apart surfaces that engage the frame side rails to limit translation of the PCB from the second operating position to the third operating position.

13. The PCB frame assembly of feature 12 wherein the surfaces of the overhanging component portions of the PCB are generally flat and extend along and against the top of the frame side rails when the PCB is in the third operating position .

14. The PCB frame assembly of feature 12 wherein the overhanging component portions of the PCB each include an outer-facing indention that defines the narrower width portion of the said overhanging components and defines the said surfaces of the overhanging components.

15. The frame assembly of feature 14 wherein the overhanging component portions of the PCB comprise spaced apart walls of a terminal block housing.

16. The PCB assembly of feature 1 wherein the PCB comprises one or more mechanical or electrical components mounted on the top surface of the first end portion of the PCB, each of the said one or more mechanical or electrical components being received in an opening in the shroud as the PCB rotates to the installed position. 17. The PCB assembly of feature 1 wherein at least portions of the side rails of the frame extend beyond the upper side of the PCB when the PCB is in the installed position .

Features of the disclosed method for inserting a printed circuit board (PCB) into a frame that includes a shroud to form a PCB frame assembly in which the shroud covers a portion of an upper surface the PCB may include the following features, alone or in combination:

1. A method for inserting a printed circuit board (PCB) into a frame that includes a shroud to form a PCB frame assembly in which the shroud covers a portion of an upper surface the PCB, the method comprising the steps of:

(a) inserting the PCB into an opening defined by the frame and thereby placing the inserted PCB into a first assembly position with respect to the frame, the upper surface of the PCB facing the frame; and

(b) rotating the PCB with respect to the frame from the first assembly position to an installed position with respect to the frame wherein the upper surface of the PCB is placed underneath the shroud.

2. The method of method feature 1 wherein the PCB when inserted into the frame has a depth of insertion, the depth of insertion of the PCB into the frame opening being limited by mechanical interference between the frame and components on the PCB.

3. The method of method feature 2 comprising the steps of:

(c) inserting the PCB into the frame opening to the maximum depth of insertion of the PCB;

(d) translating the inserted PCB along the frame to place the PCB in the first assembly position of the frame; and

(e) after performing step (d) , rotating the PCB from the first assembly position to the installed position. 4. The method of method feature 1 comprising the steps of:

(c) rotating the PCB with respect to the frame from the first assembly position to a second assembly position;

(d) translating the PCB with respect to the frame from the second assembly position to a third assembly position with respect to the frame; and

(e) rotating the PCB with respect to the frame from the third assembly position to the installed position.

5. The method of method feature 1 comprising the step of:

(c) receiving components on the PCB into openings in the shroud as the PCB rotates with respect to the frame to the installed position.

While this disclosure includes one or more illustrative embodiments described in detail, it is understood that the one or more embodiments are each capable of modification and that the scope of this disclosure is not limited to the precise details set forth herein but include such modifications that would be obvious to a person of ordinary skill in the relevant art and fall within the purview of the following claims.

Claims

1. A printed circuit board frame assembly comprising: a printed circuit board (PCB) , the PCB comprising spaced apart opposite first and second ends separated by a length of the PCB, first and second sides spaced apart by a width of the PCB, and upper and lower sides separated by a thickness of the PCB, a first portion of the PCB located at the first end and a second portion of the PCB located at the second end, the second portion of the PCB carrying a pair of overhanging component portions on the upper side of the PCB that extend outwardly beyond the first and second sides of the PCB;

a frame not integrally formed with the PCB or components carried on the PCB, the frame comprising spaced apart first and second end walls, first and second spaced apart rails joining the first and second end walls, a shroud extending between the first and second rails, the shroud comprising a first end spaced away from the first end wall, the first end wall, the rails, and the end of the shroud defining a through opening in the frame, the side rails defining a width of the frame opening;

2. The PCB frame assembly of claim 1 wherein the frame includes at least one latch that extend over the PCB after the PCB has moved from the first assembly position to the installed position, each latch resisting rotation of the PCB from the installed position towards the first assembly position .

3. The PCB frame assembly of claim 1 wherein the PCB is movable in the opening along the frame side rails when the PCB is in the first assembly position with respect to the frame, the frame comprising an abutment surface spaced from the shroud that that limits such movement of the PCB towards the shroud .

4. The PCB frame assembly of claim 3 wherein the PCB is placed against the abutment surface to place the PCB in the first assembly position, the PCB rotatable about the abutment surface to initiate movement of the PCB from the first assembly position towards the second assembly position.

5. The PCB frame assembly of claim 4 wherein the PCB is rotatable about the abutment surface from the first assembly position to a second assembly position wherein the sides of the PCB are inclined with respect to the frame side rails, the frame comprising a first guide surface parallel with the sides of the PCB when the PCB reaches the second assembly position, the PCB translatable along the first guide surface from the second assembly position to a third assembly position wherein the relative positions of the first and second PCB portions with respect to the frame are thereby established.

6. The PCB frame assembly of claim 5 wherein the PCB is rotatable from the third assembly position to the installed position .

7. The PCB frame assembly of claim 6 wherein the frame comprises a second surface adjacent the PCB when the PCB is in the third assembly position with respect to the frame, the PCB rotatable about the second surface as the PCB translates from the second assembly position to the third assembly position.

8. The PCB frame assembly of claim 7 wherein the second surface forms a portion of a second guide surface parallel with the first guide surface.

9. The PCB frame assembly of claim 8 wherein the first and second guide surfaces are formed on a generally trapezoidally- shaped projection extending from one or both of the frame side walls into the frame opening.

10. The PCB frame assembly of claim 4 wherein each frame side rail comprises a reduced-wall thickness section that receives the PCB when the PCB translates from the second assembly position to the first assembly position.

11. The PCB frame assembly of claim 4 wherein the overhanging components of the PCB define a narrower width portion of said overhanging components, the narrower width portion of said components being received between the reduced- wall thickness sections of the frame side rails when the PCB translates from the second assembly position to the third assembly position.

12. The PCB frame assembly of claim 11 wherein the overhanging component portions of the PCB define a pair of spaced apart surfaces that engage the frame side rails to limit translation of the PCB from the second operating position to the third operating position.

13. The PCB frame assembly of claim 12 wherein the surfaces of the overhanging component portions of the PCB are generally flat and extend along and against the top of the frame side rails when the PCT is in the third operating position .

14. The PCB frame assembly of claim 12 wherein the overhanging component portions of the PCB each include an outer-facing indention that defines the narrower width portion of the said overhanging components and defines the said surfaces of the overhanging components.

15. The frame assembly of claim 14 wherein the overhanging component portions of the PCB comprise spaced apart walls of a terminal block housing.

16. The PCB assembly of claim 1 wherein the PCB comprises one or more mechanical or electrical components mounted on the top surface of the first end portion of the PCB, each of the said one or more mechanical or electrical components being received in an opening in the shroud as the PCB rotates to the installed position.

17. The PCB assembly of claim 1 wherein at least portions of the side rails of the frame extend beyond the upper side of the PCB when the PCB is in the installed position .

18. A method for inserting a printed circuit board (PCB) into a frame that includes a shroud to form a PCB frame assembly in which the shroud covers a portion of an upper surface the PCB, the method comprising the steps of:

19. The method of claim 18 wherein the PCB when inserted into the frame has a depth of insertion, the depth of insertion of the PCB into the frame opening being limited by mechanical interference between the frame and components on the PCB.

20. The method of claim 19 comprising the steps of:

(e) after performing step (d) , rotating the PCB from the first assembly position to the installed position.

21. The method of claim 18 comprising the steps of:

22. The method of claim 18 comprising the step of: