MXPA98003258A - Connector block for volad initiation systems - Google Patents

Abstract

A connector block (10) includes a fastening member or clip (30), which cooperates with the signal transmitting end (12a) of the body member (12) to define between them an arcuate line retaining slot (32), within which one or more signal transmission lines (40) are received in explosive signal communication with the output end (16a) of a detonator (16). The fastening member (30) is of decreasing thickness as sensed by moving from the proximal end (30b) thereof to at least its mid-point and preferably is of an undiminished width from the proximal end (30b) thereof to the open end (32b) of the line retainer slot (32). These peculiarities and the configuration of the inlet (34) cooperate to facilitate the lateral insertion of the signal transmission lines (40) into the line retainer slot (32) and its retention therein over a wide range of operating temperatures and as well as providing an excellent shield against the metral

Description

CONNECTOR BLOCK FOR BEGINNING SYSTEMS DESCRIPTION OF THE INVENTION BACKGROUND OF THE INVENTION FIELD OF THE INVENTION The present invention relates to connector blocks of the type used to connect and initiate detonation signal transmission lines and more particularly to connect blocks that include a clip or fastener member in which localized peak stresses are reduced when the fastener member is flexed to allow the insertion of side of the signal transmission lines in a slot for retention of lines.

Description of Related Art Connector blocks for blast initiation or blasting systems are well known in the art as exemplified by U.S. Patents. 5,171,935 and 5,398,611 of RJ Michna et al., Issued respectively, on December 15, 1992 and March 21, 1995. These patents describe a connector block having a channel formed therein to receive a low energy detonator and a groove. arched within the c-al are retained one or more signal transmission lines in juxtaposition of signal transmission with the detonator. A similar construction is shown in Figure 11 of the U.S. Patent. 5,204,492 of M. Jacob et al. Issued April 20, 1993. Connecting blocks of the type illustrated by the aforementioned patents are usually molded as a single piece from a suitable organic, synthetic and thermoplastic polymeric material. Figure 4 of the U.S. Patent 5,398,611 already mentioned illustrates a plurality of signal transmission lines, such as shock tubes, which have been inserted into the arcuate slot 37 being forced to pass through the converging retaining members 42, 43 formed at the entrance to the slot 37. The retaining members 42, 43 are sized to provide a clearance, which is slightly smaller than the diameter of the shock tubes in order to prevent inadvertent withdrawal of the side of the tubes 40 from the slot 37 by forces exerted on the tubes. Conformal tubes are extended towards and connected at other sites in the blast pattern. Consequently, the side insertion of the signal transmission tubes 40 into the slot 37 requires some force to insert the tubes 40 to pass the retaining members 42, 43 because it is necessary to flex the grip member 35 (FIG. 4 of FIG. US Patent 5,398,611) for forcing the tubes 40 through the narrow clearance provided between the retaining members 42, 43. As described in column 4, line 40 and following of the US Pat. 5,398,611, the gripping member 35 is held adjacent the end of the housing "by means of elastic deformable segment 36" which flexes, that is, temporarily "deforms", to admit the tubes 40 to pass the members 42, 43 in slot 37. The connecting blocks of the type disclosed in the two above-mentioned patents of Michna et al. And with which the present invention concerns, all require some force to insert the signal transmission lines into the slot for retention of lines, because if the free space predisposed at the entrance to the slot is I did too large, the retained lines would be removed too easily and inadvertently from the line retention slot by the force imposed on them during the placement of the blasting or blasting system. The problem of side insertion is aggravated due to that such connector blocks are used outdoors under a wide variety of climatic conditions and the thermoplastic fastener or gripping member tends to become inflexible at low temperatures, requiring even greater insertion forces for side or side insertion of the lines. Such large insertion forces induce large bending efforts located in the fastener member, especially at its root or proximal end where it is attached to the body of the cor.ector block. On the other hand, if the plastic composition is modified to improve its flexibility at low temperatures, in order to reduce the effort required for insertion at low temperatures, the fastener or grip member would tend to be too easily bent and perhaps permanently deformed when The connector block is used at higher temperatures. The latter situation could result in the failure of the gripping member or fastener to retain the signal transmission lines placed precisely against the output end of the detonator, thus reducing the prospects of a reliable initiation of the signal transmission lines retained in the connector block. In addition to precisely locating the retained signal transmission lines, the grip member must serve to protect surrounding signal transmission lines from damage due to shrapnel caused by detonation of the detonator. This objective can be achieved by increasing the mass of the grip member to provide an improved shrapnel shield. However, such an increase in mass increases the inflexibility of the grip member and aggravates the side insertion problem. The prior art as exemplified by U.S. Pat. The above-mentioned 5,117,935 and 5,398,611 strive to achieve the objectives of a relatively easy insertion of the signal transmission lines over a wide range of temperatures and shrapnel protection generally by thickening the grip member opposite the outlet end of the detonator, to serve as a shrapnel shield and reducing the side insertion force required to provide a narrow neck or an articulation area around which the fastener member pivots effectively when the signal transmission tubes are inserted. (See column 4, lines 40 to 43 and 48 to 59, the gripping member 35 and the elastically deformable segment 36 of Figures 1 and 4 of U.S. Patent 5,398,611). Even when connecting blocks as illustrated in U.S. Pat. 5,398,611 have proven to be successful in their use, they have some disadvantages. One is that the narrow neck area (36 in Figure 1 of Pat. 5,398,611) provides uncovered areas from which some shrapnel can escape. Another is that the effort induced in the fastening member by insertion by sideways of the signal transmission lines is concentrated in the narrow neck, increasing the danger by permanent deformation of the fastener at high temperatures and the possibility of fracturing the fastener at temperatures extremely low In order to solve these problems, such connecting blocks are manufactured with a relatively low stiffness of the gripping member, to reduce the insertion forces of the transmission line. However, this also undesirably facilitates the inadvertent removal of the retained transmission lines as forces are imposed on them in the course of making other connections or other handling during the installation of the blasting systems. Such connecting blocks of the prior art must be manufactured with tightly controlled tolerances for the free or dead space provided by the entrance to the line retention slot, to help reduce the required insertion forces.

COMPILATION OF THE INVENTION Generally, in accordance with the present invention, there is provided a connector block having a fastener member or clip defining a line retainer slot, which solves the prior art problems set forth above. This is done by providing a fastener member which is essentially embodied as a curved beam with constant stress, which preferably has a constant width for at least a greater portion of its length starting at its proximal end. Specifically, according to the present invention, an improvement is provided in a connector block to retain one or more signal transmission lines, for example, signal transmission tubes, such as shock tubes, in a ratio of signal transfer with a detonator. The connector block comprises the following elements. A body member having a signal transmitting end and a detonator channel having a longitudinal axis and terminating at a discharge end, the channel extends into the body member to receive and retain therein a detonator which it has an outlet end, with the outlet end disposed at the discharge end of the channel when the detonator sits there. The projection of the periphery of the exit end of said detonator seated in a plane passing through the discharge end of the channel, perpendicular to its longitudinal axis, serves as the origin of a hypothetical blast cone that emanates from the discharge end of the channel and having a given apex angle. A bracket member or curved clip, line retainer is disposed at the signal transmitting end of the body member and cooperates therewith to define between the clamping member and the body member a line retainer slot, preferably of arcuate cross section which extends transversely to the longitudinal axis of the channel. The line retainer slot serves to receive and retain therein at least one signal transmission line, eg, a signal transmission tube such as a shock tube, in a signal communication relationship with said output end of the signal. a detonator retained within the receiving channel. The fastening member has a proximal end carried by the body member and a distant opposite end. The line retainer slot has a closed end adjacent the proximal end of the fastening member and an open end adjacent the distal end of the fastening member. An inlet is formed between the distal end of the clamping member and the body member, the inlet is dimensioned and configured to admit the insertion of the transmission line side therethrough and into the retention line slot by the displacement of the holding member. The improvement in the connector block comprises that the fastening member is dimensioned and configured to be of a decreasing thickness as sensed by moving from the proximal end thereof to at least approximately the intersection of the distal segment of the fastening member with a blasting cone or explosive that has an angle of ninety degrees of apex. Another aspect of the present invention provides that the fastening member is of decreasing thickness as sensed by moving from the proximal end to approximately the midpoint of the fastening member, the mid-point being defined as the intersection of an extension of the longitudinal axis with the fastening member . The fastener member has a distal member segment defined as extending from the midpoint of the fastener member to its distal end. Also, the fastening member is of a substantially uniform thickness from about the midpoint of the fastening member to at least about the intersection of the fastening member with a blasting cone having an angle of ninety degrees of apex. According to another aspect of the present invention, the fastening member has a base width at its proximal end and the width of the fastening member between its proximal end and approximately the open end of the line retaining groove is not less than the base width. A related aspect of the invention provides that the base width is at least sufficiently wide to close a blast cone having an angle of ninety degrees of apex, preferably, that is at least wide enough to close a blast cone having an angle of one hundred degrees of apex. In accordance with another aspect of the present invention, the fastening member has a distal member segment defined as extending from the midpoint of the fastening member towards its distal end, the midpoint of the fastening member being defined as the intersection of an extension. of the longitudinal axis with the fastening member.

Also, the fastening member is dimensioned and configured to have at least between its proximal end and the intersection with the distant segment of a blasting member holding member having an angle of ninety degrees of apex, the geometry of a beam with stress a constant having a longitudinal axis of beam and which has been formed in a curved configuration by bending the beam while maintaining the longitudinal axis of the beam in a vertical plane passing through the longitudinal axis of the beam. Other aspects of the present invention provide that the connector block is comprised of a polymeric, organic, synthetic material, for example, one selected from the group consisting of polyethylene, polypropylene, polybutylene, and acrylonitrile-butadiene-styrene copolymer. Yet another aspect of the present invention provides that the connector block also comprises an entrance guide carried by the distal end of the fastening member and an entrance ramp carried by the body member. The entrance guide and the entrance ramp are arranged on respectively opposite sides of the entrance and cover each other to define a covered entrance in the guide direction in the line retainer slot. The entrance guide and the entrance ramp provide a free entrance space between them and define between them an entrance angle from approximately 18 degrees to 22 degrees, for example, 20 degrees. The entry guide defines with the central longitudinal axis of the detonator channel a fastener reaction angle from approximately 115 degrees to 120 degrees, for example approximately 120. Yet another aspect of the present invention provides that the free entry space supplied between the entry guide and entry ramp change as movement is detected laterally across the width of the entrance. For example, the free entry space may decrease as detected by moving laterally across the width of the entrance in opposite inward directions from the opposite lateral sides of the connector block to a point where the free entry space is at a minimum. In a preferred embodiment of this aspect of the invention, the free entry space is at a minimum in, and is symmetric about, the lateral center of the entrance. Another aspect of the present invention provides that the slot free space provided by the line retainer slot between the clamping member and the body member changes as detected by laterally moving the connector body over the entire width of the slot. For example, the slot free space decreases as detected by laterally moving across the width of the slot in opposite inward directions from the opposite side edges of the connector block to a point where the slot free space is at a minimum. In a preferred embodiment, the slot free space is at a minimum in, and is symmetric about, the lateral center of the slot. Other aspects of the present invention provide that the connector block is combined with a detonator having an outlet end, for example, a retarder detonator, and that the detonator is disposed within the detonator channel with the outlet end disposed at the end. of signal transmission of the body member. Still other aspects of the present invention will become apparent in the following description and in the drawings appended thereto. The reference made here and in the claims to the "side" insertion of a signal transmission line in the line retainer slot of a connector block, refers to the insertion method illustrated schematically in FIG. 5, wherein a length of the signal transmission line is forced through the entrance 34 with the longitudinal axis of the inserted length of the line placed transversely, ie substantially and perpendicular to the direction of its travel through the entrance and therefore in the line retainer slot 32. This is the usual connection modc because, typically, the ends of the signal transmission lines that are inserted in the connector block 12 are not available to be threaded through the line retainer slot 32 in the manner of threading a needle. This is because the ends of the inserted lines are remote and / or immobilized and / or connected to other connecting blocks or to another device.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective view of a connector block according to an embodiment of the present invention; Figure 2 is a side elevational view of the connector block of Figure 1; Figure 2A is a partial sectional view taken along line 2A-2A of Figure 2; Figure 2B is a partial sectional view taken along line 2B-2B of Figure 2; Figure 2B-1 is a somewhat enlarged version of Figure 2B showing a diagrammatic blast cone; Figure 2C is a partial sectional view taken along line 2C-2C of Figure 2; Figure 2D is a view, enlarged with respect to Figure 2, of the left portion (seen from Figure 2) of the connector block of Figure 2 and showing a plurality of transmission lines retained there; Figure 2D-1 is a somewhat enlarged version of Figure 2D showing a diagrammatic blasting cone of Figure 2B-1; Figure 2E is a perspective view taken along the line 2E-2E of Figure 1; Figure 2F is a partial perspective view, with sectioned parts, of the signal transmission end of the connector block of Figure 1; Figure 2G is a view identical to that of Figure 2B, but of another embodiment of the present invention; Figure 3 is a partial sectional view taken along a vertical plane through the central longitudinal axis of the connector block of Figure 2; Figure 4 is a schematic, partial side elevational view of the left portion (seen from Figure 2) of the connector block of Figure 2 with a transmission line shown at the inlet a, the line retainer slot; Figure 5 is a schematic perspective view, with parts broken away for clarity of the illustration, of the portion of the connector block illustrated schematically in Figure 4; Figure 6 is a partial top view of the signal transmission end of a first connector block of the prior art; Figure 6A is an elevation cross-sectional view taken along line A-A of Figure 6; and Figure 7 is an elevation view, in partial cross section taken along the longitudinal axis of a second connector block of the prior art; and Figure 8 is a schematic diagram that is used to help demonstrate the design parameters of the beam with constant stress employed in the design of the fastener members of the connector blocks of the present invention.

DETAILED DESCRIPTION OF THE INVENTION AND ITS PREFERRED EMBODIMENTS Figure 1 shows a connector block 10 comprising a body member 12 having a signal transmitting end 12a and an immobilizing end 12b. A channel for detonator 14 (Figures 1, 2 and 5) is of hexagonal cross section and extends through the body member 12 and is sized and configured to receive therein a detonator 16 as illustrated in Figure 3. The channel for detonator 14 has a longitudinal central axis LL (FIGS. 1 and 2) which, in FIG. 2, partially overlaps the line of section 2B-2B. The detonator 16 is of conventional construction and has a closed outlet end 16a and an opposite open end 16b, which is closed in the conventional manner by crimping the cover (unnumbered) of the detonator around an elastomeric bushing 18, only the protruding end of which is visible in figure 3. As is conventional, the detonator 16 has a crimp 16c formed adjacent its open end 16b. The pressure crimp I6c secures the bushing 18 and a signal transmission line 20, sectioned in FIG. 3, in place within the detonator 16 and seals the open end 16b against the environment. The detonator 16 contains an explosive charge 22 at the outlet end 16a thereof. As is well known, the detonator 16 typically includes a delay train of a suitable pyrotechnic material interposed between the explosive charge 22 and the signal transmission line 20 to provide a predetermined delay period between the reception of the signal in the detonator 16 through the signal transmission line 20 and the detonation of the explosive charge 22. The signal transmission line 20 typically has a length from approximately 2.4 to 61 meters (about 8 to 200 feet and at its free end (the end which is opposite the crimped end inside the detonator 16), this can be connected to a cigarette lighter or crimped into a high-energy detonator (not shown) suitable for use in the initiation of the detonation of a primary exploded load This type of arrangement is illustrated in US Patent 3,987,732 of R. W: Spraggs et al., issued October 26, 1976. Of course, the free end of the signal transmission line 20 can be otherwise properly connected and the connector block of Figure 3 can be used in any suitable blasting system as is well known to those skilled in the art. it comprises a housing having a passageway 24 that extends transversely to the detonator channel 14 and into which an offset, arcuate, immobilizing member 26 mounted at a cost or to leave free the channel for detonator 14. The immobilizing member 26 may be of the type described in greater detail in the patent application also pending Serial No. 08 / 249,522, filed on May 26, 1994 in the name of Daniel P. Sutula, Jr. And titled "Molded article that has a displaced member or integral members and method of use", now US Patent (reference of attorney P-1393), or your request for continuation in part also pending Serial No. 08 / 548,590, filed on October 26, 1995 in the name of Thomas C. Tseka et al. entitled "Connector block having means detonator set immobilizers "(reference of proxy P-1393-1). The detonator 16 (figure 3) is mounted inside the connector block 10 by inserting the outlet end 16a of the detonator 16 into the channel 14 of the immobilizing end 12b (figure 1). The detonator 16 is then advanced through the channel 14 until the exit end 16a comes to rest against the stops 28a, 28b (figures 2B, 3 and 5). The detonator 16 is dimensioned and configured so that with the outlet end 16a positioned against the stops 28a, 28b, the pressure crimp 16c will be aligned with the immobilizing member 26, which is then advanced through the passageway 24 toward the Right, seen from Figure 1, so that the immobilizing member 26 engages the pressure crimp 16c and both the detonator 16 and the immobilizing member 26 are secured in place within the connector block 10. The immobilizing member 26 has an opening (FIG. not shown) formed therein at its end, which is enclosed within the passageway 24, whose opening is configured to provide a pair of legs of the immobilizing member 26, which extend apart as they pass through the crimp 16c and which spring together again to engage the immobilizing member 26 with the pressure crimping 16c. This configuration of the immobilizing member 26 is illustrated and explained in detail in the aforementioned pending patent applications Nos. Nos. 08 / 249,522 and 08 / 548,590.

The connector block 10 includes a curved fastening member, line retainer 30 disposed at the signal transmitting end 12a of the body member 12. The fastening member 30 cooperates with the body member 12 to define between them a line retainer slot 32. , which is arcuate in cross-section and has a laterally extending width of the connector body 12 across the width of the groove, i.e., transverse to the longitudinal axis LL of the channel 14. The width of the line retaining groove 32 is defined by, by way of example, is the same as, the base width w of the fastening member 30 at the proximal end 30b thereof (Figures 2A, 2B and 2G). As best seen in Figure 2D, an inlet 34 to the line retainer slot 32 is formed between the distal end 30a of the fastener member 30 and the raised array 36 on the body member 12 in a location adjacent the remote end 30a of the fastening member 30. An entry guide 34a is formed at the distal end 30a and an entry ramp 34b is formed in the raised formation 36. The entry guide 34a and the entry ramp 34b are arranged mutually opposite and converging towards each other in the direction moving from the inlet 34 towards the interior of the line retainer slot 32 to define a convergent entry leading to the retainer slot of lines 32. As seen in the 2D figures and 2E, the free space is provided between the entrance guide 34a and the entrance ramp 34b for lateral insertion of a signal transmission line 40 through it, the free space is smaller than the diameter of the signal transmission lines to to be used with the connector block, thus requiring the signal transmission line to flex or open the fastener member 30 slightly to achieve admission to the line retainer slot 32.

Once inserted there, the fastening member 30 returns to its original position, reducing the free space of the entrance 34 and, in cooperation with the flat shoulder 35 (figures 2 and 2F), avoid the removal of the signal transmission line retained. The proximal end 30b of the fastening member 30 is carried by the body member 12 on the bottom or bottom side 12c thereof and the fastening member 30 terminates at the distal end 30a thereof adjacent the opposite upper side 12d of the body member 12 The body member 12 has a first lateral side 12e (figure 1) and a second opposite lateral side 12f (figures 2A and 2B). The configuration of the fastening member 30, as best seen in the profile view in Figures 2, 2D, 3 and 4, is designed to distribute the stresses developed during side insertion of the signal transmission lines substantially equal to length of the profile of the fastener. That is, when signal transmission lines such as shock tubes, deflagrating tubes or the like are inserted sideways through the inlet 34, the fact that the diameter of such tubes is greater than the minimum free space supplied by the inlet 34, requires deflection of the fastening member 30 to force the line into the line retaining groove 32. Such deflection causes stresses on the entire material of the fastening member 30. Such effort, thanks to the design of the inlet 34 and the fastening member 30 as described herein, it is generally reduced and equally distributed along the length of the fastener member 30 as compared to the prior art designs, so that the peak stresses are reduced. This reduces the force required for insertion even at extremely low temperatures and reduces the possibility of the fastener member becoming deformed or damaged even at extremely high temperatures. The anticipated temperature range to which the connecting blocks can be exposed during storage and use is -40 ° C to 71.11 ° C (-40 ° F to +160 ° F). The design of the fastening member 30, according to the present invention (only one embodiment of which is illustrated in the drawings), can be realized by applying the theory constant stress on a beam to the design of the fastening member: The theory of effort Beam constant is typically used when designing beams by weight and efficiency, which will be subject to static loads. As applied herein for the design of the fastener member 30, the theory is used to minimize the peak forces induced in a curved part, when the part is subjected to a given deflection at a given specific load. According to the foregoing, the design of the fastening member 30 is analogous, at least for a segment of its length starting from the proximal end 30b thereof, to that of a beam with constant stress, which is a beam whose thickness is optimizes such that, for a given load, the buckling stress is maintained at a constant value along the length of the beam. The concept is illustrated in Figure 8, which shows a diagram of a cantilevered beam 70, supported at one end by a support 72, the cross-sectional area of the beam 70 decreases as detected by moving in the direction from the end. next 70b of the cantilevered beam 70 towards the distant end 70a thereof. For a given load imposed on the cantilever beam 70, the resultant buckling stress is maintained at a constant value throughout the length of the beam. This is illustrated by the following formula (1) S = Me / I where S is the induced stress due to the bending moment M. The bending moment M is calculated by means of the following formula (2) M = F? sc) where F is the force applied to the beam and x is the distance between the point at which F is applied and the point at which the cantilever beam 70 is supported, in the support 72 in the diagram of figure 8. The bending moment M can therefore be calculated in any given cross section of the cantilever beam 70 at a distance x from the applied load F. The constant c / I is a parameter that considers the geometry of the cross section of the beam. The bending stress S will be maintained at a constant value for any value of F and x by the appropriate selection of the geometry parameter c / I. The grip member of the present invention is achieved by bending the hypothetical cantilever beam 70 by flexing the distal end 70a thereof upwards, keeping the beam 70 in a vertical plane passing through its longitudinal axis, i.e., while it maintains the longitudinal axis of the beam 70 in the plane of the paper in which figure 8 is represented. The resulting curved structure will provide the fastening member 30 of the present invention, with the further modification of adding a hooked accessory or flap and an entry guide on the distal end 70a, for the purposes explained herein. Applying formula (1) to a curved structure such as that of a fastening member 30, returns the following formula to calculate the actual stress Sa induced in the fastening member 30: (3) Sa = Fn / A - Kt (Mc / ) where Sa is the stress in a given minimum area cross section, Fn is the component of the reaction load perpendicular to the minimum area cross section, A is the area area of the minimum area cross section, c is the distance of the neutral axis of the fastener member curved to its outermost fiber on the concave surface of the fastening member, that is, the surface that forms part of the line retaining groove 32. Kt is the stress concentration factor for considering the curvature of the fastening member , M is the bending moment in the minimum area cross section imposed by the reaction load component parallel to the minimum area cross section and I is the section module of the fastener member. The minimum area cross section is taken through the fastening member and is illustrated by the cross section of the fastening member 30 indicated by the line AA in Figure 4, wherein the plane passing through the line AA is perpendicular to the lines. lines tt and t'-t ', which are lines of planes tangent to the profile of the fastening member 30 as seen in Figure 4. The minimum area cross section is the cross section cut by the plane AA.

The stress concentration factor Kt described in connection with the formula, or the calculation to determine it, is readily available for particular curvatures in standard reference work in the field of material mechanics. For example, see Stress Concentration Design Factors by R. E. Peterson, published by John Wiley & Sons, Inc., New York, London, Sydney. The other components of the stress calculation formula given above, as is well known to those skilled in the art, are easily obtained from standard reference works or by calculation. Figure 4 is useful to illustrate the definition of the "thickness" of a fastener member according to that term is used herein and in the claims. The thickness of the fastening member 30 at any point along the length is the thickness as measured along the plane of any minimum area cross section, i.e. the distance measured along the plane AA between the lines tt and t '-t'. As another example, the thickness T (FIG. 4) is the thickness as measured at the midpoint of the fastening member 30. As is known in the art, the power of the explosive force generated by the initiation of the explosive charge 22 (FIG. 3) of the exploder 16 can be described with respect to a "blasting cone" of the explosive force emanating from the explosive charge 22 upon initiation. Figures 2B-1 and 2D-1 show a hypothetical blasting cone C that does not attempt to approximate the actual blasting cone, but which is intended only as a hypothetical geometric device to provide reference points for identifying locations along, and widthwise, of the fastening member 30. Such identification is also facilitated by considering that the portion of the fastening member 30 from and between the proximal end 30b thereof to its midpoint comprises the proximal section 31b (FIG. 2D) of the fastening member 30 and that the portion from and between the midpoint of the fastening member 30 to the distal end 30a thereof comprises the distal section 31a (FIG. 2D) of the fastening member 30. As defined elsewhere herein, the midpoint of the fastening member 30 is its intersection with an extension of the longitudinal axis LL. The hypothetical blast cone C is considered to emanate from the projection of the periphery of the outlet end 16a of the detonator 16 (figure 3) onto an imaginary plane II (figures 2B-1 and 2D-1) passing through the end of the discharge 14a (FIG. 2F) of the channel 14 perpendicular to the longitudinal axis LL of the channel 14. The discharge end of the channel 14 is defined as the location within the channel 14 in which the tip of the outlet end 16a of the detonator 16 is located. In the illustrated mode, the internal surface of the stops 28a, 28b define the discharge end 14a, through which the plane I-I passes. The surface of the blast cone C is indicated by the dot and dash lines in Figures 2B-1 and 2D-1, whose lines extend backwards from the plane II to the apex (unnumbered) of the hypothetical blast cone C with the In order to clearly illustrate its apex angle oc. The pattern of the actual blasting effect caused by the initiation of the explosive charge 22 will differ from (is larger than) the hypothetical blasting cone C. However, the hypothetical blasting cone C as defined is, as noted above, useful for defining particular locations along the fastening member 30 in terms of the intersection of the distal segment of the fastening member 31a with a hypothetical blasting cone C of various apex angles. The apex angle <; x illustrated in Figures 2B-1 and 2D-1 is ninety degrees. Referring again to Figures 2B, 2D and 4, the fastening member 30 is dimensioned and configured to decrease in thickness as it is sensed by moving the proximal end 30b thereof at least to a point at which it would be intersected by a blasting cone. C having an apex angle ° c of ninety degrees, as illustrated in Figures 2B-1 and 2D-1. The thickness of the fastening member 30 is selected to be thick enough to be effective as a shield for the shrapnel generated by the initiation of the detonator 16, but not so thick as to require excessive force to deflect the fastener member 30 for the side insertion. the signal transmission lines within the retainer slot e lines 32. The fastening member 30 also has a width that is substantially equal to the base width w (Figures 2A, 2B and 2G) which is the width of the fastening member 30. at the proximal end 30b thereof. The width along the fastening member 30 from the proximal end 30b to the distal end 30a must be wide enough to not only securely hold the transmission lines 40, but so that the fastening member 30 can effectively serve as a shield to the shrapnel. As best seen in Figure 2B-1, the width of a given design of the fastening member 30 is best expressed in terms of a width that is sufficiently large to close, ie block or seal, a blast cone C of a apex angle set. Such a definition accommodates both the width of the fastening member 30 and its distance from the discharge end of the channel 14, as determined by the depth of the receiving groove of lines 32. As shown in Figure 2B-1, the width of the member fastener 30 is greater than that required to close the illustrated blast cone C having an apex angle? of ninety degrees and is large enough to close a blasting cone C having a vaster apex angle, eg, one hundred degrees or greater. As will be appreciated from Figure 2D-1, because the fastening member 30 circumscribes more than 180 ° around the discharge end of the channel 14, the length of the fastening member 30 is more than adequate for the purposes of shielding the shrapnel. As illustrated in Figure 2D-1, the thickness of the fastening member 30 of the illustrated embodiment decreases as detected by moving from the proximal end 30b towards the midpoint of the fastening member 30. The midpoint of the fastening member 30 is defined as the intersection of the longitudinal axis LL with the fastening member 30. From that mid-point to approximately the intersection of the fastening member 30 with a blasting cone C having an apex angle of about ninety degrees, the thickness of the fastening member 30 is substantially uniform . From that point to the distal end 30a the thickness of the fastening member 30 varies and increases to form the distal end 30a and the entry guide 34a. The proximal end 30b of the fastening member 30 has formed a pair of stress-relieving cavities 38a, 38b (Figures 2A and 2D) respectively on a first lateral side 12e and a second lateral side 12f (Figure 2A) of the connector block 10. These stress-relieving cavities help to release the stress in which it tends to be a high stress area, thus contributing to maintaining the levels of stress in the fastener member 30 within a relatively narrow margin, that is, avoiding high stress levels located at the proximal end 30b of the fastener member 30. Although cavities are illustrated in triangular form, those with dexterity in the art they will recognize that other configurations of cavities such as round, square or other cylindrical shapes, or a cavity that extends entirely through the body member 12, that is, if the stress releasing cavities 38a and 38b are mutually connected, they could be used to distribute efforts equitably. Referring now to Figures 2, 2A and 4, an end wall 32a defines the closed end of the line retainer slot 32 (Figure 3F) and the inner end of the entrance ramp 34b defines the open end 32b of the retention slot lines 32. The end wall 32a is in the shape of a gallon or? in plan view (FIG. 2A) to form in cross section an apex 32a 'in the lateral center of the detonator channel 14. As used herein and in the claims, reference to the "lateral center" of the connector block 10 or of any component or portion thereof refers to the center of the connector block as determined, with the block positioned horizontally, by a vertical plane passing through it, which intersects the central longitudinal axis LL of the detonator channel 14. For example, with Referring to Fig. 1, assuming that the connector block 10 is placed horizontally with its bottom side 12c (Fig. 2) facing downward, a vertical plane passing through the central longitudinal axis LL will define the lateral center of the connector block 10. The intersection of the imaginary plane with the connector block 10 is shown in Figure 1 by the dot-dash line. The apex 32a 'of the end wall 32a is located in the lateral center and tapers uniformly from the apex 32a' back towards the immobilizing end 12b. The stops 28a, 28b have outer surfaces 28a 'and 28b' (FIGS. 2, 2B, 2C, 2G and 3) which face towards the retaining groove of transmission lines 32 and are rounded in profile, but do not taper back toward the immobilizing end 12b moving in the direction away from the longitudinal center line of the detonator channel 14 and towards the lateral sides 12e, 12f of the body member 12. However, in an alternative embodiment, the posterior ahusamientc could be provided for the length entire of the line retainer slot 32, instead of only a portion thereof as provided by the structure illustrated in FIG. 2B. Figure 2G illustrates the tapered version. As seen in Figures 2A and 2G, the tapered backward configuration provides minimal clearance within the line retainer slot 32 along its lateral center. That minimum clearance is usually slightly smaller than the diameter of the transmission lines to be inserted into the slot 32, so that the lines are securely caught and retained in alignment along the lateral center of the slot 32 and are thus retained and centered at the outlet end 16a of the detonator 16. With this construction, the free space available for the signal transmission lines 40 retained within the slot 32 is larger in the regions of the line retainer slot 32 that are closer to the opposite lateral sides 12e and 12f of the connector block 10. This free space that increases from the slot 32 as detected by moving away from the lateral center towards the lateral sides 12e and 12f reduces the frictional resistance of the transmission lines of signal 40 as they are inserted by lateral paths into the line retainer slot 32, thus reducing the force required to insert the signal transmission lines 40 and reduce the stress on the fastening member 30. Likewise the increased free space of the slot 32, in the regions remote from the lateral center, for example, at the closed end of the slot 32 in the end wall 32a (Figure 2) gives the signal transmission lines 40 some freedom to flex and bend to an arcuate shape, thus facilitating the insertion of the last signal or tube transmission line (FIG. for example, the tube 40/6 of Figure 2D) which completely fills the retainer slot of lines 32 and must be "tightened" behind the previously inserted tubes. Figure 2D shows the line retainer slot 32 filled to capacity by six signal transmission lines 40, which are subsequently numbered 1 to 6, respectively, to indicate both their position within the line retainer slot 32 and the order in which they were introduced there through the entry 34. Figure 5 ours, partially sectioned and partially in phantom sketch, to the signal transmission line 40/1 in its place within the retainer slot of lines 32 at its end closed and the signal transmission line 40/2 next to insert sideways into the line retainer slot 32 via the input 34 (figure 2D). The rounded profile of the external surfaces 28a 'and 28b' of the stops 28a, 28b, as best seen in FIGS. 2F and 4, facilitates a smooth side entry of the signal transmission lines 40/1 to 40. / 5 (FIG. 2D) within the retainer slot of lines 32. The rounded profile also slides the signal transmission lines 40/3 and 40/4 away from the output end 16a of the detonator 16 and thus allows the lines of 40/2 and 40/5 transmission are placed closer to the central line (central longitudinal axis LL) of the detonator 16 and therefore closer to the area of maximum explosive force generated by the detonation of the explosive charge 22 (figure 3) contained at the output end 16a. This improves the reliability of the initiation of a signal within the signal transmission lines 40/2 and 40/5 in positions 2 and 5 without adversely affecting the prospects for the initiation of lines 40/3 and 40/4 in positions 3 and 4 because the latter, despite being moved slightly away from the explosive charge 22, are still in the direct line of fire of the same. Referring now to FIG. 4, there are illustrated angles measured in the vertical central plane passed through the longitudinal central axis LL of the detonator channel 14 (and the connector block 10) that is, the plane of the paper on which it is placed. renders figure 4. (The transverse shading of the cross section was omitted in the schematic figure 4). The signal transmitting end 12a and the holding member 30 of the connector block 10 are delineated instead of presented in cross section. The entrance angle A is the angle formed between the entrance guide 34a and the entrance ramp 34b. The angle A is selected to provide the optimum mechanical advantage for forcing the open fastening member 30 to yield the side insertion of the signal transmission line 40. What is desired is that the entry angle A be sufficiently small so that the work path for the side insertion of the transmission line 40, that is, the distance that the line 40 travels in contact with and imposes a force on the entry guide 34a and the entry ramp 34b, is sufficiently long so that the work required to force the open fastener member 30 sufficiently to admit the line 40 into the line retainer slot 32 is spread in the working path, to thereby reduce the peak load. In the illustrated embodiment, a suitable entry angle is 20 degrees and, generally, this angle will preferably be from about 18 degrees to about 22 degrees. Preferably, the travel length of the work path of the signal transmission line 40, that is, the trip while imposing a force on the entry guide 34a and on the entry ramp 34b, will be approximately 1.5 to 4 times the diameter of the signal transmission line 40. For example, a connector block designed to be used with a conventional sized shock tube having an outer diameter of approximately 3.05 mm (0.120 inches) may employ an inlet having a length of Work trajectory of approximately 4.6 to 12.3 mm (0.18 to 0.48 inches). The. construction of the inlet 34, the entry guide 34a and the entry ramp 34b according to the present invention provide a structure that helps to avoid or reduce the need for high peak forces for the insertion of side of the signal transmission line 40 within the line retaining slot 32. The reaction angle 3 of the holding member is selected such that the force applied to the entry guide 34a generally acts perpendicular to the theoretical "hinge" around which the holding member 30 is flexes to open and admit line 40 into the line retainer slot 32. This maximizes the efficiency of the force applied to flex the open fastener member 30 and also help reduce peak forces on the fastener member 30. In the embodiment illustrated, the entry guide 34a and the entry ramp 34b are of curved profile, as best seen in Figure 2E and are as close as possible to provide r the minimum clearance 34c in the center of the connector block 10, so that the frictional resistance to the insertion of the side of the lines 40 is reduced while the forces imposed by the insertion of the side of the lines 40 on the entry ramp 34b and the entry guide 34a are essentially and exclusively imposed on the vertical central plane passing through the longitudinal centerline LL of the detonator channel 14 (and connector block 10).

Referring now to Figure 2F, the entrance ramp 34b formed in the raised formation 36, is seen to include a small, rectangular, flat shoulder section 35 near the end of the entrance ramp 34b. The flat shoulder section 35 provides a positive effect by increasing the force required to remove a retracted signal transmission line 40 from the line retainer slot 32. Therefore, regardless of the relatively low forces required to insert a transmission line of side signal 40 within the line retainer slot 32, a sufficiently large withdrawal force is required, thus helping to prevent inadvertent removal of a retained signal transmission line. Such removal, if not detected, would of course have the disastrous effect of removing one of the signal transmission lines 40 from the signal transfer range with the detonator 16. Figures 6 and 6A are partial views of the signal transmission end 44a of the body member 44 of a first connector block of the prior art 42. The connector block 42 has a grip member 46 connected to the end of the body member 44 by an elastically deformable segment or neck 48. A line retainer slot 50 it is formed between the grip member 46 and the body member 44. A trench-like, open channel 52 is formed within the body member 44 and has gripping means (not shown) formed therein to retain a detonator within the body. channel 52 with its outlet end positioned adjacent the line retainer slot 50. The entrance ramps 54a, 54b and the entry guides 56a, 56b are provided to form an entrance towards the ran 50 for the side insertion of the signal transmission lines such as shock tubes, not shown in Figures 6 and 6A. Fig. 7 is a partial view of the output transmission end 60a of the body member 60 of a second connector block of the prior art 58. The connector block 58 has a grip member 62 that is spaced from the body member 60 to define between them a line retaining groove 64. The grip member 62 has a proximal end 62b carried by the body member 60 and a distal end 6'2a in which an inlet guide 66a is carried. The entry ramp 66b is ed in the body member 60 opposite the entry guide 66a to provide an entrance to the line retaining slot 64. A channel 6c is formed within the body member 60. An estimate of the forces required to insert the transmission lines of se to the side, within the retaining slots of lines provided by two connecting blocks of the prior art of Figures 6 / 6A (hereinafter referred to as "comparative block A") and that of Figure 7 (hereinafter referred to as "comparative block B") and the embodiment of the present invention illustrated in Figures 1 to 5 thereof (hereinafter referred to as "the block of Figure 2"). The calculations were made for connecting blocks that have the following specifications and are configured as shown respectively in Figures 2, 6 / 6A and 7. The calculations gave the results summarized in the following TABLE, where comparative is abbreviated as "Comp. " TABLE Comp. Block A Four 23.6 0.130 (Figures 6, 6A) Comp. Block B Six 46.9 0.063 (Figure 7) Block Figure 2 Six 27.3 0.047 (Figures 1 to 5) m Capacity based on your standard size shock e that has a nominal outside diameter of 3.05 itim (0.120 inches) (2) Deflection load, the force required to flex the fastener member 0.121 inches (3.05 mm) in the open direction, in kilograms. (3> Maximum deformation, the maximum deformation induced in the clamping member by the deflection load.

The data of the TABLE were calculated based on the respective designs of the comparative block A, the comparative block B and the block of figure 2 of the invention, having all the same properties of materials, that is, assuming that the three blocks were made from the same thermoplastic material. The calculations were also based on the premise that the width w (Figures 2B and 2G) of each of the three fastening members is identical and the thickness T (Figure 4) of the fastening members of the comparative block B and the block of the Figure 2 at its midpoints (at the point where an extension of the longitudinal axis of the detonator receiver channel intersects the fastener member) is 5,283 mm (0.208 inches). The thickness T (Fig. 4) of the comparative block A does not enter into the calculations because the comparative block A flexes substantially and entirely on the neck 48 thereof, so that substantially all the bending stresses are located on the neck 48. to the foregoing, the thickness of the clamping or gripping member 46 of the comparative block A at its midpoint is not apt to calculate neither the deflection load nor the maximum stress of the TABLE. The calculations were based on the neck 46 having a width (as seen in figure 6) of 6.35 mm (0.25 inches) and a depth (as seen in figure 6A) of 6.35 mm (0.25 inches). The effect of forcing a deflection in the clamping members of the comparative blocks A and B and the block of figure 2 sufficient to force open the entrance to provide a free space of 3.05 mm (0.120 inches) in the entrance (for example , at the entrance 34 of figure 3) was calculated in a direction along the plane (PP in figure 2E) which is perpendicular to the entrance 34 in the minimum free space 34c. In the illustrated embodiment, the plane P-P is the vertical plane, referred to above, which intersects the longitudinal axis of the connector block to define its "lateral center". It should be noted from the TABLE that the force required to open the fastener to achieve the deflection of 3.05 mm (0.120 inches) is 23.6 kg (52 pounds) for the comparative block A, 46.9 kg (103.5 pounds) for the comparative block B and 27.3 kg (60.2 pounds) for the block in figure 2. Although comparative block A required slightly less opening force to achieve the desired opening deflection, it maintains a deformation by maximum stress greater than that which they maintain any of the comparative block B or the block of figure 2. The deformation by high maximum stress maintained by the comparative block A is due to its narrow neck portion (48 in figure 6) in which the deflection stress is concentrated. It is apparent from the much greater maximum strain strain of comparative block A compared to the block of figure 2, that the latter would be much more capable of withstanding large deflections or operating very high temperature conditions than would the comparative block. A. Although the maximum stress strain of the comparative block B is much better than that of the comparative block A, this is still significantly greater than that of the block of figure 2. In addition to the deformation by maximum stress maintained by the block Comparative B, which is 1.34 times the maximum stress strain of the block of Figure 2, the deflection load required to achieve the deflection of 3.05 mm (0.120 inches) of comparative block B, is 1.72 times greater than that required by the block of figure 2. If it were desired to reduce the deflection load of comparative block B to be identical to that of the block of figure 2 , the thickness of the shield of comparative block B, would have to be reduced from 5,588 mm (0.220 inches) to approximately 3,912 mm (0.154 inches). (This calculation is based on the fact that the flexural stiffness of the clamping member will vary with the third power of the thickness T of the fastener). In comparison, the block of Figure 2 has a shield thickness of approximately 5,283 mm (0.208 inches). While the invention has been described with reference to a preferred and particular embodiment thereof, it will be appreciated by those skilled in the art having read and understood the foregoing description that numerous designs of connecting blocks other than the specific embodiment illustrated may be obtained, nevertheless which fall within the spirit and scope of the present invention. It is intended to include all those other designs and substantial equivalents thereof within the scope of the appended claims.

Claims (23)

1. CLAIMS 1. In a connector block for retaining one or more signal transmission lines in signal transfer relationship with a detonator, the connector block comprises: a body member having a signal transmitting end and a channel for detonator that has a longitudinal axis and ending at one discharge end, the channel extends within the body member, to receive and retain there a detonator having an outlet end, with the outlet end disposed at the discharge end of the channel when the detonator is seated there, the projection of the periphery of the outlet end of the detonator seated on a plane passing through the discharge end of the channel perpendicular to the longitudinal axis thereof, serves as the origin of a hypothetical blast cone that emanates from the discharge end of the channel and having a given apex angle; a curved fastening member, line retainer disposed at the signal transmission end of the body member and cooperating therewith to define between them a line retaining groove extending transversely to the longitudinal axis of the channel for receiving and retaining there at least a signal transmission line in a signal communication relationship with the output end of a detonator retained within the receiver channel, the fastener member having a proximal end carried on the body member and an opposite distant end and the retainer slot of The line has a closed end adjacent to the proximal end of the fastening member and an open end adjacent to the distal end of the fastening member; an entrance formed between the distal end of the fastening member and the body member, the inlet is dimensioned and configured to admit the insertion of side of the transmission line through it and into the retention slot of lines, by means of the -displacement of the holding member, thus imposing a reaction load on the holding member: the improvement is understood in that the holding member is dimensioned and configured to be of a continuously decreasing thickness as sensed by moving longitudinally along the holding member from its proximal end to at least about the first intersection found of the fastener member with a blast cone having a ninety degree apex angle.
2. 2. The connector block of claim 1, wherein the fastening member is of a continuously decreasing thickness as sensed by moving longitudinally along the fastening member from its proximal end to approximately the midpoint of the fastening member, the mid-point is defined as the intersection of an extension of the longitudinal axis with the fastening member, and the fastening member has a distant segment of fastening member defined as extending from the midpoint of the fastening member towards its distal end and wherein the distant segment of fastener member is of a substantially uniform thickness from about the midpoint of the fastener member to at least about the intersection of the distance segment of fastener member with a hypothetical blast cone having a ninety degree apex angle.
3. 3. The connector block of claim 1 or 2, wherein the clamping member has a base width at its proximal end and the base width of the clamping member between its proximal end and approximately the open end of the retention-line groove is not less than the base width.
4. 4. The connector block of claim 3, wherein the base width is at least wide enough to close a hypothetical blast cone having an apex angle of ninety degrees.
5. 5. The connector block of claim 3, wherein the base width is at least large enough to close a hypothetical blast cone having an apex angle of one hundred degrees.
6. 6. The connector block of claim 1, wherein the body member has a bottom side and an opposite top side, the proximal end of the holder member is carried on the bottom side and the distal end of the holder member ends adjacent to the side higher.
7. 7. The connector block of claim 1 or 2, wherein the fastening member has a distance segment of fastening member defined as extending from the midpoint of the fastening member to its distal end, the midpoint of the fastening member is defined as the intersection of an extension of the longitudinal axis with the fastening member, and wherein the fastening member is dimensioned and configured to have, at least between its proximal end and the intersection with the distant segment of fastening member of a hypothetical blast cone having an angle of ninety degree apex, the geometry of a beam with constant stress having a beam longitudinal axis, in which the clamping member is of a continuously decreasing thickness, as detected by moving longitudinally from its proximal end towards its distant segment; and whose beam with constant stress has been formed in a curved configuration, curving it while maintaining the longitudinal axis of the beam in a vertical plane passing through the longitudinal axis of the beam.
8. 8. The connector block of claim 1 or 2, comprised of an organic, synthetic polymeric material.
9. 9. The connector block of claim 8, wherein the organic, synthetic polymeric material is selected from the group consisting of polyethylene, polypropylene, polybutylene, and acrylonitrile-butadiene-styrene copolymer.
10. 10. The connector block of claim 1 or 2, further comprising an inlet guide at the distal end of the fastening member and an entrance ramp carried in the body member, the entry guide and the entry ramp are arranged on sides respective opposites of the input and mutually converge to define a convergent entry as detected by moving in the direction leading to the line retainer slot, the entry guide and the entry ramp provide a free entry space therebetween and define between them an entry angle of approximately 18 degrees to 22 degrees and the entry guide defines with the central longitudinal axis of the channel for the detonator a bra reaction angle of approximately 115 to 120 degrees.
11. 11. The connector block of claim 10, wherein the entry angle is approximately 20 degrees and the reaction angle of the fastener is approximately 120 degrees.
12. 12. The connector block of claim 1 or 2, in combination with the detonator having an outlet end, the detonator sits within the detonator channel, with the outlet end of the detonator disposed at the discharge end of the channel.
13. 13. The connector block of claim 12, wherein the detonator is a delay detonator.
14. 14. The connector block of claim 1 or 2, which also includes one or more stress releasing cavities formed in the proximal end of the fastening member.
15. 15. The connector block of claim 1 or 2, further comprising an entrance ramp carried in the entrance body member, the entrance ramp has a flat shoulder disposed at the open end of the line retainer slot.
16. 16. The connector block of claim 1 or 2, wherein the line retainer slot is of arcuate configuration and is dimensioned and configured to move away from the discharge end of the channel to the signal transmission lines retained within the slot. line retainer as they align axially with the channel, whereby such compliant signal transmission lines are allowed to be adjacent to the displaced signal transmission lines, to be placed closer to the discharge end of the channel.
17. 17. In a connector block for retaining one or more signal transmission lines in signal transfer ratio with a detonator, the connector block comprises: a body member having a signal transmitting end and a channel for detonator having a shaft longitudinal and terminating at one discharge end, the channel extends within the body member, to receive and retain therein a detonator having an outlet end, with the outlet end disposed at the discharge end of the channel when set there the detonator, the projection of the periphery of the exit end of the detonator seated on a plane that passes through the discharge end of the channel perpendicular to the longitudinal axis thereof, serves as the origin of a hypothetical blast cone that emanates from the discharge end of the channel and having a given apex angle; a curved fastening member, line retainer disposed at the signal transmission end of the body member and cooperating therewith to define between them a line retaining groove extending transversely to the longitudinal axis of the channel for receiving and retaining there at least a signal transmission line in a signal communication relationship with the output end of a detonator retained within the receiver channel, the fastener member having a proximal end carried on the body member and an opposite distant end and the retainer slot of The line has a closed end adjacent to the proximal end of the fastening member and an open end adjacent to the distal end of the fastening member; an inlet formed between the distal end of the fastening member and the body member, the inlet is dimensioned and configured to admit the insertion of the transmission line side therethrough and into the line retainer slot, by moving the fastener member, thereby imposing a reaction load on the fastener member; the improvement is understood in that: an entry guide is carried at the distal end of the fastening member and an entry ramp is carried in the body member, the entry guide and the entry ramp are disposed on respective opposite sides of the input to provide a free space of entry therebetween and mutually converge to define a convergent entry as detected by moving in the direction of guidance towards the line retainer slot, and the input free space changes as detected by moving laterally through the width of the entrance; and the fastening member is dimensioned and configured to be of a continuously decreasing thickness as sensed by moving longitudinally along the fastening member from its proximal end to at least approximately the first intersection encountered of the fastening member with a blasting cone having an angle of ninety degree apex, the entrance guide and the entrance ramp define between them an entrance angle of approximately 18 degrees to 22 degrees and the entrance guide defines with the central longitudinal axis of the detonator channel a bra reaction angle from approximately 115 degrees to 120 degrees.
18. 18. The connector block of claim 17, wherein the inlet clearance decreases as detected by moving laterally across the width of the inlet in opposite inward direction from the opposite lateral sides of the connector block to a point where the clearance Input is at a minimum.
19. 19. The connector block of claim 18, wherein the free entry space is at a minimum in, and is symmetric about, the lateral center of the entrance.
20. 20. In a connector block for retaining one or more signal transmission lines in signal transfer ratio with a detonator, the connector block comprises: a body member having a signal transmitting end and a channel for detonator having a shaft longitudinal and ending at one end of discharge, the channel extends within the body member, to receive and retain there a detonator having an outlet end, with the exit end disposed at the discharge end of the channel when the detonator is settled there, the projection of the periphery the outlet end of the detonator seated on a plane passing through the discharge end of the channel perpendicular to the longitudinal axis thereof, serves as the origin of a hypothetical blast cone emanating from the discharge end of the channel and having a given apex angle; a curved fastening member, line retainer disposed at the signal transmission end of the body member and cooperating therewith to define between them a line retaining groove extending transversely to the longitudinal axis of the channel for receiving and retaining there at least a signal transmission line in a signal communication relationship with the output end of a detonator retained within the receiver channel, the fastener member having a proximal end carried on the body member and an opposite distant end and the retainer slot of The line has a closed end adjacent to the proximal end of the fastening member and an open end adjacent to the distal end of the fastening member; an inlet formed between the distal end of the fastening member and the body member, the inlet is dimensioned and configured to admit the insertion of the transmission line side therethrough and into the line retainer slot, by moving the fastener member, thus imposing a reaction load on the fastener member: the improvement is understood in that the fastener member is dimensioned and configured to be of a continuously decreasing thickness as sensed by moving longitudinally along the fastener member from its proximal end to at least about the first intersection found of the holding member with a blast cone having a ninety-degree apex angle, and the line retaining slot provides a slot free space between the holding member and the body member and the clearance slot changes as detected by moving laterally of the connector body through the to the width of the slot.
21. 21. The connector block of claim 20, wherein the gap of the slot changes as detected by moving laterally across the width of the slot in opposite inward directions from the opposite side sides of the connector block to a point where the space of slot is at a minimum.
22. 22. The connector block of claim 21, wherein the slot free space is at a minimum in, and is symmetric about, the lateral center of the slot.
23. 23. The connector block of claim 17 or 20, wherein the fastening member is of a decreasing thickness as sensed by moving longitudinally along the fastening member from its proximal end to approximately the midpoint of the fastening member, the midpoint is defined as the intersection of an extension of the longitudinal axis with the fastening member, and the fastening member has a distant segment of fastening member defined as extending from the midpoint of the fastening member towards its distal end and wherein the fastening member is of a thickness substantially uniform from about the midpoint of the fastener member to at least about the intersection of the distance segment of fastener member with a hypothetical blast cone having a ninety degree apex angle.