OPERATING APPARATUS FOR WATER SAMPLERS
United States Patent 3841162
A water sampler having a tubular body open at both ends and through which extends a connecting rod fixed at one end to a closure for the lower end of the body and carrying an enlargement at its other end for engagement with and disengagement from a latching clasp supported on a closure for the upper end of the body. The latching clasp comprises a pair of segment-shaped plates between which the enlargement is adapted to be retained, each of the plates having an upstanding motion transmitting member operable to move the plates apart and effect release of the enlargement. The clasp plates preferably are biased to move toward one another by two springs which straddle the connecting rod.
US Patent References:
Liquid gauging device
Summers - February 1937 - 2071145
Sea sampler
Spilhans - March 1943 - 2314372
Pressure liquid sampling system and apparatus
Gibbon - April 1968 - 3379065
WATER SAMPLING DEVICE
Keir - March 1973 - 3714830
Liquid gauging device
Summers - February 1937 - 2071145
Sea sampler
Spilhans - March 1943 - 2314372
Pressure liquid sampling system and apparatus
Gibbon - April 1968 - 3379065
WATER SAMPLING DEVICE
Keir - March 1973 - 3714830
Application Number:
05/314498
Publication Date:
10/15/1974
Filing Date:
12/13/1972
View Patent Images:
Export Citation:
Assignee:
Trippensee Corporation (Saginaw, MI)
Primary Class:
International Classes:
G01N1/12; G01N1/10
Field of Search:
73/425.4R,421R,425.2
Primary Examiner:
Queisser, Richard C.
Assistant Examiner:
Yasich, Daniel M.
Attorney, Agent or Firm:
Learman & McCulloch
Claims:
What is claimed is
1. Water sampling apparatus comprising a hollow body open at its opposite ends and adapted to be lowered to a predetermined depth in a body of water; first closure means for one end of said body; second closure means for the other end of said body; means connecting said first and second closure means for relative movements toward and away from one another and toward and away from the associated ends of said body to effect closure of said body; latch means carried by said connecting means; a pair of clasp members; means mounting said clasp members on one of said closure means for linear movements toward and away from one another into and out of engagement with said latch means for respectively disabling and enabling said relative movements of said connecting means and said closure means; biasing means acting on said clasp members and urging them toward one another; and motion transmitting means fixed to each of said clasp members and being spaced from one another, the spacing between said motion transmitting means being such as to accommodate therebetween a messenger operable to effect movement of said clasp members away from one another when said clasp members engage said latch means and thereby effect the disengagement of said latch means by said clasp members, whereby said closure members are enabled to effect closure of said hollow body.
2. Apparatus according to claim 1 wherein said clasp members straddle said latch means.
3. Apparatus according to claim 1 wherein said biasing means comprises spring means.
4. Apparatus according to claim 1 wherein said connecting means extends through at least one of said one of said closure members and wherein said clasp members straddle said connecting means.
5. Apparatus according to claim 4 wherein said latch means comprises an enlargement on said connecting means and wherein each of said clasp members has an opening therein corresponding substantially to one-half the transverse dimension of said connecting means but less than substantially one-half the corresponding dimension of said latch means.
6. Apparatus according to claim 1 wherein each of said clasp members includes an upstanding part, said parts being spaced from one another.
7. Apparatus according to claim 1 wherein said clasp members are mounted on said one of said closure members in confronting relation for movements toward and away from each other.
8. Apparatus according to claim 7 wherein said clasp members are segment shaped.
9. Apparatus according to claim 8 wherein each of the opposite ends of each of said segment shaped clasp members has a substantially semicircular opening therein, and wherein said mounting means comprises a pair of headed anchor elements having their shanks accommodated in said semicircular openings and their heads overlying said segment shaped clasp members.
10. Apparatus according to claim 9 including a pair of spring members connecting said clasp members and located adjacent each end thereof, said spring members biasing said clasp members toward one another.
1. Water sampling apparatus comprising a hollow body open at its opposite ends and adapted to be lowered to a predetermined depth in a body of water; first closure means for one end of said body; second closure means for the other end of said body; means connecting said first and second closure means for relative movements toward and away from one another and toward and away from the associated ends of said body to effect closure of said body; latch means carried by said connecting means; a pair of clasp members; means mounting said clasp members on one of said closure means for linear movements toward and away from one another into and out of engagement with said latch means for respectively disabling and enabling said relative movements of said connecting means and said closure means; biasing means acting on said clasp members and urging them toward one another; and motion transmitting means fixed to each of said clasp members and being spaced from one another, the spacing between said motion transmitting means being such as to accommodate therebetween a messenger operable to effect movement of said clasp members away from one another when said clasp members engage said latch means and thereby effect the disengagement of said latch means by said clasp members, whereby said closure members are enabled to effect closure of said hollow body.
2. Apparatus according to claim 1 wherein said clasp members straddle said latch means.
3. Apparatus according to claim 1 wherein said biasing means comprises spring means.
4. Apparatus according to claim 1 wherein said connecting means extends through at least one of said one of said closure members and wherein said clasp members straddle said connecting means.
5. Apparatus according to claim 4 wherein said latch means comprises an enlargement on said connecting means and wherein each of said clasp members has an opening therein corresponding substantially to one-half the transverse dimension of said connecting means but less than substantially one-half the corresponding dimension of said latch means.
6. Apparatus according to claim 1 wherein each of said clasp members includes an upstanding part, said parts being spaced from one another.
7. Apparatus according to claim 1 wherein said clasp members are mounted on said one of said closure members in confronting relation for movements toward and away from each other.
8. Apparatus according to claim 7 wherein said clasp members are segment shaped.
9. Apparatus according to claim 8 wherein each of the opposite ends of each of said segment shaped clasp members has a substantially semicircular opening therein, and wherein said mounting means comprises a pair of headed anchor elements having their shanks accommodated in said semicircular openings and their heads overlying said segment shaped clasp members.
10. Apparatus according to claim 9 including a pair of spring members connecting said clasp members and located adjacent each end thereof, said spring members biasing said clasp members toward one another.
Description:
The disclosed invention relates to apparatus for effecting the remote closing of opposite ends of a normally open water sampling tube of the kind that is adapted to be lowered to a known depth in a body of water and have its ends closed so as to entrap in the tube a sample of water taken at the known depth. Sampling devices of the kind to which the invention relates conventionally are known as Kemmerer style water samplers.
For some limnological and oceanographic studies it is important that samples of water at different, known depths be taken and that such samples be protected against dilution or modification due to leakage of the sampler during retrieval of the latter. The Kemmerer style water sampler was designed for this purpose and comprises a hollow tube, normally open at both ends, and having top and bottom closures or stoppers which are adapted to be moved from open positions to sealing positions in response to the dropping of a weighted messenger along the line or cable which supports the sampler. The stoppers of a Kemmerer style sampler are latched in their open positions and the upper stopper includes a latch release mechanism which is tripped by the weighted messenger to enable the stoppers to move to their closed positions.
The latch release mechanism of the kind in use heretofore leaves much to be desired, as is evidenced by the fact that the release mechanism is only 80% or less effective. Unfortunately, it is not always possible to know when the release mechanism fails to function, and even if each failure could be detected, the operating messenger cannot be retrieved for another operating attempt. As a consequence, a great deal of time is lost in obtaining samples and, in many cases, so much time is lost that the vessel used in the studies has passed the area from which samples are desired.
One of the major difficulties with latch release mechanism of the kind used heretofore is that of assuring sufficient movement of the movable parts of the latch mechanism to insure releasing of the latch. The conventional latch release mechanism comprises a pair of oscillatable arms pivoted to one another at corresponding ends and connected at their other ends by a tension spring. Each arm carries an upstanding ear between which the weighted messenger is adapted to seat, the messenger being wedge-shaped so as to swing the arms apart. In many instances, however, the messenger fails to seat properly between the ears, thereby preventing swinging movement of the arms.
Another cause of failure of pivoted arm latch release mechanisms often is due to the fact that the sampler is in a position inclined to the vertical, because of currents or the like, as a result of which the weighted messenger engages the ear of one arm only and expends its energy in swinging the associated arm. Unless both arms pivot, the latch cannot be released, but mechanisms in use heretofore have incorporated no means to insure movement of both of the arms before the energy of the weighted messenger is spent.
The pivoted arm latch release mechanism conventionally used with Kemmerer style samplers has included a spring for biasing the free ends of the arms toward one another, i.e., toward latching positions, but such spring often has been mounted in an exposed position. As a consequence, the spring is susceptible to damage as well as to being moved during operation of the sampler. In either event, proper operation of the latch release mechanism is not obtained.
An object of this invention is to provide apparatus for effecting the closing of the ends of a Kemmerer style water sampler and which overcomes the disadvantages of apparatus heretofore in use for similar purposes.
Another object of the invention is to provide apparatus of the kind referred to and wherein the latch release mechanism incorporates a pair of clasp plates which are mounted for linear movement to assure latch releasing movement of the plates even though a weighted messenger imperfectly engages the plates.
A further object of the invention is to provide a pair of linearly movable clasp plates of the kind described and wherein movement of the plates in latch releasing directions is limited so as to insure movement of both plates prior to the expenditure of the energy of the weighted messenger.
Another object of the invention is to provide spring biasing means for such clasp plates and wherein the springs are protected from damage or inadvertent movement.
Other objects and advantages of the invention will be pointed out specifically or will become apparent from the following description when it is considered in conjunction with the appended claims and accompanying drawings, in which:
FIG. 1 is an elevational view, partly in section, of a Kemmerer style water sampler having latch releasing mechanism constructed in accordance with the invention, the closures of the sampler being latched in open position;
FIG. 2 is a view similar to FIG. 1 of the upper closure, but rotated through 90°;
FIG. 3 is an enlarged, top plan view of the upper closure and illustrating the latch releasing mechanism in latch engaging condition;
FIG. 4 is a view similar to FIG. 3, but illustrating the latch releasing mechanism in released condition;
FIG. 5 is an enlarged sectional view taken on the line 5--5 of FIG. 2;
FIG. 6 is an enlarged sectional view taken on the line 6-- 6 of FIG. 2; and
FIG. 7 is an enlarged fragmentary transverse sectional view taken on the line 7--7 of FIG. 3.
Apparatus constructed according to the invention is adapted for use in conjunction with a water sampler of the Kemmerer type having a cylindrical, tubular body 1 open at both ends. Extending coaxially through the body 1 is a hollow connecting rod 2 which is slideably supported by bearings 3 carried by spider-like supports 4 that are welded or otherwise suitably fixed to the interior of the body. The rod 2 has a considerably greater length than that of the body 1 and is fixed at one end to a closure 5 comprising a truncated, conical 14 and 6 formed of rubber or rubbery material sandwiched between metallic plates 7 and 8. The rod 2 extends through aligned secured in the members 6, 7, and 8 and is fixed with respect thereto by nuts 9 and 10. An outlet 11 of conventional construction also is incorporated in the closure 5 for the purpose of permitting the contents of the body 1 to be drained when desired.
The sampler also includes an upper closure 12 having a truncated, conical body 13 of rubber or rubbery material sandwiched between metal plates 14nd 15. The body 13 is provided with a bore 16 within which is located a sleeve 17, the sleeve being s ecured to the upper and lower plates 14 and 15, respectively. The plate 14 has an opening 18 and the plate 15 has a similar opening (not shown) through which the connecting rod 2 slideably extends.
The upper end of the connecting rod 2 is provided with an enlargement or latch part 19 of greater diameter than that of the sleeve 17 and the opening 18, and the enlargement 19 is located above the upper end of the sleeve 17 so as to prevent movement of the closure 12 off the upper end of the rod 2. The closure 12, however, is capable of sliding movement along the rod toward the opposite or lower closure 5.
The lower plate 15 is provided with anchor lugs 20 to which corresponding ends of tether chains 21 are fixed, the opposite ends of the chains being fixed to anchor members 22 carried by the upper support 4. The chains 21 limit movement of the closure 12 in a direction away from the adjacent end of the body 1, but permit movement of the closure toward the body so as to enable the closure to seat on and seal the adjacent or upper end of the body 1.
The apparatus thus far described is conventional in a Kemmerer style water sampler and forms no part of the invention per se, aside from the manner in which it cooperates with apparatus yet to be described.
Latch release mechanism constructed according to the invention is designated generally by the reference character 25 and comprises a pair of segment-shaped clasp plates 26 and 27 mounted on the plate 14 for linear reciprocating movements toward and away from one another. The clasp plates 26 and 27 are mounted by means of headed screws 28 and 29 carried by the plate 14 in diametrically opposed positions, the heads of the screws projecting beyond the level of the plates 26 and 27 so as to permit the latter to be accommodated between the plate 14 and the heads of the screws.
The clasp plates 26 and 27 have confronting edges 30 and 31, respectively, which are adapted to abut one another. To enable the edges to abut one another, they are provided with semi-circular recesses 32 and 33 at their opposite ends for the accommodation of the shanks of the screws 28 and 29. The confronting surfaces 30 and 31 of the clasp plates also are recessed as at 34 and 35, so as to provide an opening of such size as to accommodate the enlargement 19 on the rod 2 when the non-relieved portions of the edges 30 and 31 of the clasp plates abut one another. The confronting surfaces of the clasp plates also are relieved, as at 36 and 37, respectively to form flanges 34a, 35a overlying the recesses 34 and 35 for a purpose to be explained hereinafter.
The clasp plates 26 and 27 constantly are biased toward one another by springs 38 and 39, the spring 38 being fitted into aligned grooves 40 and 41 formed in the lower surface of the plates 26 and 27 at one side of the rod 2 and the spring 39 being fitted into similar grooves 42 and 43 at the opposite side of the connecting rod. The opposite ends of the spring 38 are enlarged to fit into lateral recesses 44 and 45 formed at the closed ends of the grooves 40 and 41 and the opposite ends of the spring 39 are similarly enlarged to fit into lateral recesses 46 and 47 formed at the closed ends of the grooves 42 and 43. The opposite ends of the springs thus are anchored to bias the clasp plates toward each other but the plates are capable of movement in a direction away from each other from the positions shown in FIG. 6.
Means are provided to limit movement of the clasp plates away from one another and comprise a pin 48 on the plate 26 and a similar pin 49 on the plate 27, both of the pins projecting beyond the lower surface of the respective clasp plates. The pin 48 is accommodated in a circular groove 50 formed in the plate 14 and the pin 49 is accommodated in a similar groove 51 formed in the plate 14. The arrangement is such that movement of the clasp plates 26 and 27 away from one another causes the pins 48 and 49 to traverse their respective grooves until the pins engage the radially inner edge of such grooves, whereupon further movement of the clasp plates in a direction away from one another is prevented.
The clasp plates 26 and 27 carry upstanding motion transmitting lugs or ears 52 and 53 which confront but are spaced from one another. Movement imparted to either of the ears 52 or 53 effects corresponding movement of the associated clasp plate.
To condition the apparatus for operation one end of a line or cable 54 is threaded through the connecting rod 2 from the upper end of the latter. The line extends beyond the lower closure 5 and is provided with a knot or other stop (not shown) to prevent return movement of the line through the rod, thereby enabling the line 54 to support the entire sampling apparatus. The latch part or enlargement 19 at the upper end of the rod 2 then is fitted into the recesses 34 and 35 between the plates 26 and 27 so that the enlargement 19 is trapped between the plate 14 and the overhanging flanges 34a and 35a. The flange 34 and 35 define an opening of lesser diameter than that of the enlargement 19. The closure 12 thus is supported by the enlargement 19 of the member 2.
When the closure 12 is supported by the enlargement 19, the entire sampling apparatus may be suspended from the line 54, whereupon the body 1 will be supported by means of the tether chains 21 at a fixed distance below the closure 12 and the closure 5 will be supported by the rod 2 at a fixed distance below the lower end of the body 1. In these positions of the parts, both ends of the sampler body 1 are open and the sampling apparatus may be lowered to any desired depth in a body of water.
When the sampler has been lowered to a predetermined depth, a weighted, conically shaped messenger 55 may be fitted onto the upper end of the cable 54 and permitted to fall. As the messenger falls, it will be guided by the cable so as to enable the messenger to engage the closure 12 between the upstanding ears 52 and 53. As the messenger engages the ears, the messenger will move the ears away from one another and the ears will transmit such movement to the clasp plates 26 and 27, against the force of the springs 38 and 39, thereby enlarging the opening defined by the flanges 34a and 35a. When the diameter of such opening is equal to or greater than the diameter of the enlargement 19, the weight of the closure 12 will cause the latter to fall toward the upper end of the sampling body 1. As the closure 12 falls, the body 1 also will fall toward the closure 5 until such time as the latter seats in the lower end of the body 1. Following seating of the closure 5 in the lower end of the sampling body, the closure 12 will seat in the upper end of the body, thereby sealing both ends of the sampling body. The sampling apparatus then may be hoisted by means of the cable 54.
Should the sampler be tilted in such manner that the messenger 55 engages only one of the ears 52 or 53, the clasp plate connected to that ear will be moved away from the other clasp plate, but only by an amount corresponding to the clearance between the associated pin 48, 49 and groove 50, 51. Upon taking up this clearance, further movement of the clasp plate away from its companion clasp plate is prohibited, whereupon the messenger will be deflected toward the other ear and effect movement of it, together with its associated clasp plate in a direction to effect release of the latch part 19. Thus, either of the clasp plates may be moved from latching position to latch releasing position prior to the expenditure of the messenger's energy and thereby virtually assure release of the latching mechanism.
The extent that each clasp plate may move in a direction away from its companion clasp plate should be only that required to provide vertical clearance between the associated flange 34a or 35a and the periphery of the latch part 19. Thus, the extent of such movement may be controlled accurately by the relative diameters of the pins 48, 49 and the grooves 50, 51.
The disclosed embodiment is representative of a presently preferred form of the invention, but is intended to be illustrative rather than definitive thereof. The invention is defined in the claims.
For some limnological and oceanographic studies it is important that samples of water at different, known depths be taken and that such samples be protected against dilution or modification due to leakage of the sampler during retrieval of the latter. The Kemmerer style water sampler was designed for this purpose and comprises a hollow tube, normally open at both ends, and having top and bottom closures or stoppers which are adapted to be moved from open positions to sealing positions in response to the dropping of a weighted messenger along the line or cable which supports the sampler. The stoppers of a Kemmerer style sampler are latched in their open positions and the upper stopper includes a latch release mechanism which is tripped by the weighted messenger to enable the stoppers to move to their closed positions.
The latch release mechanism of the kind in use heretofore leaves much to be desired, as is evidenced by the fact that the release mechanism is only 80% or less effective. Unfortunately, it is not always possible to know when the release mechanism fails to function, and even if each failure could be detected, the operating messenger cannot be retrieved for another operating attempt. As a consequence, a great deal of time is lost in obtaining samples and, in many cases, so much time is lost that the vessel used in the studies has passed the area from which samples are desired.
One of the major difficulties with latch release mechanism of the kind used heretofore is that of assuring sufficient movement of the movable parts of the latch mechanism to insure releasing of the latch. The conventional latch release mechanism comprises a pair of oscillatable arms pivoted to one another at corresponding ends and connected at their other ends by a tension spring. Each arm carries an upstanding ear between which the weighted messenger is adapted to seat, the messenger being wedge-shaped so as to swing the arms apart. In many instances, however, the messenger fails to seat properly between the ears, thereby preventing swinging movement of the arms.
Another cause of failure of pivoted arm latch release mechanisms often is due to the fact that the sampler is in a position inclined to the vertical, because of currents or the like, as a result of which the weighted messenger engages the ear of one arm only and expends its energy in swinging the associated arm. Unless both arms pivot, the latch cannot be released, but mechanisms in use heretofore have incorporated no means to insure movement of both of the arms before the energy of the weighted messenger is spent.
The pivoted arm latch release mechanism conventionally used with Kemmerer style samplers has included a spring for biasing the free ends of the arms toward one another, i.e., toward latching positions, but such spring often has been mounted in an exposed position. As a consequence, the spring is susceptible to damage as well as to being moved during operation of the sampler. In either event, proper operation of the latch release mechanism is not obtained.
An object of this invention is to provide apparatus for effecting the closing of the ends of a Kemmerer style water sampler and which overcomes the disadvantages of apparatus heretofore in use for similar purposes.
Another object of the invention is to provide apparatus of the kind referred to and wherein the latch release mechanism incorporates a pair of clasp plates which are mounted for linear movement to assure latch releasing movement of the plates even though a weighted messenger imperfectly engages the plates.
A further object of the invention is to provide a pair of linearly movable clasp plates of the kind described and wherein movement of the plates in latch releasing directions is limited so as to insure movement of both plates prior to the expenditure of the energy of the weighted messenger.
Another object of the invention is to provide spring biasing means for such clasp plates and wherein the springs are protected from damage or inadvertent movement.
Other objects and advantages of the invention will be pointed out specifically or will become apparent from the following description when it is considered in conjunction with the appended claims and accompanying drawings, in which:
FIG. 1 is an elevational view, partly in section, of a Kemmerer style water sampler having latch releasing mechanism constructed in accordance with the invention, the closures of the sampler being latched in open position;
FIG. 2 is a view similar to FIG. 1 of the upper closure, but rotated through 90°;
FIG. 3 is an enlarged, top plan view of the upper closure and illustrating the latch releasing mechanism in latch engaging condition;
FIG. 4 is a view similar to FIG. 3, but illustrating the latch releasing mechanism in released condition;
FIG. 5 is an enlarged sectional view taken on the line 5--5 of FIG. 2;
FIG. 6 is an enlarged sectional view taken on the line 6-- 6 of FIG. 2; and
FIG. 7 is an enlarged fragmentary transverse sectional view taken on the line 7--7 of FIG. 3.
Apparatus constructed according to the invention is adapted for use in conjunction with a water sampler of the Kemmerer type having a cylindrical, tubular body 1 open at both ends. Extending coaxially through the body 1 is a hollow connecting rod 2 which is slideably supported by bearings 3 carried by spider-like supports 4 that are welded or otherwise suitably fixed to the interior of the body. The rod 2 has a considerably greater length than that of the body 1 and is fixed at one end to a closure 5 comprising a truncated, conical 14 and 6 formed of rubber or rubbery material sandwiched between metallic plates 7 and 8. The rod 2 extends through aligned secured in the members 6, 7, and 8 and is fixed with respect thereto by nuts 9 and 10. An outlet 11 of conventional construction also is incorporated in the closure 5 for the purpose of permitting the contents of the body 1 to be drained when desired.
The sampler also includes an upper closure 12 having a truncated, conical body 13 of rubber or rubbery material sandwiched between metal plates 14nd 15. The body 13 is provided with a bore 16 within which is located a sleeve 17, the sleeve being s ecured to the upper and lower plates 14 and 15, respectively. The plate 14 has an opening 18 and the plate 15 has a similar opening (not shown) through which the connecting rod 2 slideably extends.
The upper end of the connecting rod 2 is provided with an enlargement or latch part 19 of greater diameter than that of the sleeve 17 and the opening 18, and the enlargement 19 is located above the upper end of the sleeve 17 so as to prevent movement of the closure 12 off the upper end of the rod 2. The closure 12, however, is capable of sliding movement along the rod toward the opposite or lower closure 5.
The lower plate 15 is provided with anchor lugs 20 to which corresponding ends of tether chains 21 are fixed, the opposite ends of the chains being fixed to anchor members 22 carried by the upper support 4. The chains 21 limit movement of the closure 12 in a direction away from the adjacent end of the body 1, but permit movement of the closure toward the body so as to enable the closure to seat on and seal the adjacent or upper end of the body 1.
The apparatus thus far described is conventional in a Kemmerer style water sampler and forms no part of the invention per se, aside from the manner in which it cooperates with apparatus yet to be described.
Latch release mechanism constructed according to the invention is designated generally by the reference character 25 and comprises a pair of segment-shaped clasp plates 26 and 27 mounted on the plate 14 for linear reciprocating movements toward and away from one another. The clasp plates 26 and 27 are mounted by means of headed screws 28 and 29 carried by the plate 14 in diametrically opposed positions, the heads of the screws projecting beyond the level of the plates 26 and 27 so as to permit the latter to be accommodated between the plate 14 and the heads of the screws.
The clasp plates 26 and 27 have confronting edges 30 and 31, respectively, which are adapted to abut one another. To enable the edges to abut one another, they are provided with semi-circular recesses 32 and 33 at their opposite ends for the accommodation of the shanks of the screws 28 and 29. The confronting surfaces 30 and 31 of the clasp plates also are recessed as at 34 and 35, so as to provide an opening of such size as to accommodate the enlargement 19 on the rod 2 when the non-relieved portions of the edges 30 and 31 of the clasp plates abut one another. The confronting surfaces of the clasp plates also are relieved, as at 36 and 37, respectively to form flanges 34a, 35a overlying the recesses 34 and 35 for a purpose to be explained hereinafter.
The clasp plates 26 and 27 constantly are biased toward one another by springs 38 and 39, the spring 38 being fitted into aligned grooves 40 and 41 formed in the lower surface of the plates 26 and 27 at one side of the rod 2 and the spring 39 being fitted into similar grooves 42 and 43 at the opposite side of the connecting rod. The opposite ends of the spring 38 are enlarged to fit into lateral recesses 44 and 45 formed at the closed ends of the grooves 40 and 41 and the opposite ends of the spring 39 are similarly enlarged to fit into lateral recesses 46 and 47 formed at the closed ends of the grooves 42 and 43. The opposite ends of the springs thus are anchored to bias the clasp plates toward each other but the plates are capable of movement in a direction away from each other from the positions shown in FIG. 6.
Means are provided to limit movement of the clasp plates away from one another and comprise a pin 48 on the plate 26 and a similar pin 49 on the plate 27, both of the pins projecting beyond the lower surface of the respective clasp plates. The pin 48 is accommodated in a circular groove 50 formed in the plate 14 and the pin 49 is accommodated in a similar groove 51 formed in the plate 14. The arrangement is such that movement of the clasp plates 26 and 27 away from one another causes the pins 48 and 49 to traverse their respective grooves until the pins engage the radially inner edge of such grooves, whereupon further movement of the clasp plates in a direction away from one another is prevented.
The clasp plates 26 and 27 carry upstanding motion transmitting lugs or ears 52 and 53 which confront but are spaced from one another. Movement imparted to either of the ears 52 or 53 effects corresponding movement of the associated clasp plate.
To condition the apparatus for operation one end of a line or cable 54 is threaded through the connecting rod 2 from the upper end of the latter. The line extends beyond the lower closure 5 and is provided with a knot or other stop (not shown) to prevent return movement of the line through the rod, thereby enabling the line 54 to support the entire sampling apparatus. The latch part or enlargement 19 at the upper end of the rod 2 then is fitted into the recesses 34 and 35 between the plates 26 and 27 so that the enlargement 19 is trapped between the plate 14 and the overhanging flanges 34a and 35a. The flange 34 and 35 define an opening of lesser diameter than that of the enlargement 19. The closure 12 thus is supported by the enlargement 19 of the member 2.
When the closure 12 is supported by the enlargement 19, the entire sampling apparatus may be suspended from the line 54, whereupon the body 1 will be supported by means of the tether chains 21 at a fixed distance below the closure 12 and the closure 5 will be supported by the rod 2 at a fixed distance below the lower end of the body 1. In these positions of the parts, both ends of the sampler body 1 are open and the sampling apparatus may be lowered to any desired depth in a body of water.
When the sampler has been lowered to a predetermined depth, a weighted, conically shaped messenger 55 may be fitted onto the upper end of the cable 54 and permitted to fall. As the messenger falls, it will be guided by the cable so as to enable the messenger to engage the closure 12 between the upstanding ears 52 and 53. As the messenger engages the ears, the messenger will move the ears away from one another and the ears will transmit such movement to the clasp plates 26 and 27, against the force of the springs 38 and 39, thereby enlarging the opening defined by the flanges 34a and 35a. When the diameter of such opening is equal to or greater than the diameter of the enlargement 19, the weight of the closure 12 will cause the latter to fall toward the upper end of the sampling body 1. As the closure 12 falls, the body 1 also will fall toward the closure 5 until such time as the latter seats in the lower end of the body 1. Following seating of the closure 5 in the lower end of the sampling body, the closure 12 will seat in the upper end of the body, thereby sealing both ends of the sampling body. The sampling apparatus then may be hoisted by means of the cable 54.
Should the sampler be tilted in such manner that the messenger 55 engages only one of the ears 52 or 53, the clasp plate connected to that ear will be moved away from the other clasp plate, but only by an amount corresponding to the clearance between the associated pin 48, 49 and groove 50, 51. Upon taking up this clearance, further movement of the clasp plate away from its companion clasp plate is prohibited, whereupon the messenger will be deflected toward the other ear and effect movement of it, together with its associated clasp plate in a direction to effect release of the latch part 19. Thus, either of the clasp plates may be moved from latching position to latch releasing position prior to the expenditure of the messenger's energy and thereby virtually assure release of the latching mechanism.
The extent that each clasp plate may move in a direction away from its companion clasp plate should be only that required to provide vertical clearance between the associated flange 34a or 35a and the periphery of the latch part 19. Thus, the extent of such movement may be controlled accurately by the relative diameters of the pins 48, 49 and the grooves 50, 51.
The disclosed embodiment is representative of a presently preferred form of the invention, but is intended to be illustrative rather than definitive thereof. The invention is defined in the claims.