US3826144A

US3826144A - Apparatus for sampling liquids

Info

Publication number: US3826144A
Application number: US00373072A
Authority: US
Inventors: G Wessels
Original assignee: Dow Chemical Co
Current assignee: Dow Chemical Co
Priority date: 1973-06-25
Filing date: 1973-06-25
Publication date: 1974-07-30
Anticipated expiration: 1991-07-30

Abstract

The apparatus disclosed herein is useful for collecting liquids, particularly water. A preferred form of the apparatus includes a platform, which supports one or more open-end containers. A rigid bar is positioned upright to the platform, and the lower end of the bar is fastened into the platform. A line is attached to a fastener ring at the top end of the bar. The line is used to raise and lower the unit into a liquid body to collect the sample in the containers. When the liquid fills each container, the apparatus is raised to the surface and a hinged closure assembly seals the open end of each container.

Description

United States Patent [191 Wessels 111 3,826,144 [451 July 30,1974

Primary Examiner-S. Clement Swisher Attorney, Agent, or Firm-V. Dean Clausen; Lloyd S. Jowanovitz [5 7] ABSTRACT The apparatus disclosed herein is useful for collecting liquids, particularly water. A preferred form of the apparatus includes a platform, which supports one or more open-end containers. A rigid bar is positioned upright to the-platform, and the lower end of the bar is fastened into the platform. A line is attached to a fastener ring at the top end of the bar. The line is used to raise and lower the unit into a liquid body to collect the sample in the containers. When the liquid fills each container, the apparatus is raised to the surface 1 and a hinged closure assembly seals the open end of each container.

6 Claims, 4 Drawing Figures BACKGROUND OF THE INVENTION This invention relates to an apparatus for collecting liquid samples. The apparatus is particularly suitable for obtaining samples from a large body of liquid, such as a stream or a lake.

It can sometimes be a difficult task to collect samples from a lake or a stream for purposes of analysis. An example of a difficult situation is where the operator is positioned on shore or on a bridge and the sample must be obtained from a distant point in the lake or stream. A device commonly used to obtain the sample is an open container, such as a bucket, to which a line is attached for retrieving the container. Use of open containers to collect liquid samples, however, has several disadvantages.

One disadvantage of the open container is that the surrounding air can mix with the sample once the container is brought to the surface of the water; This can be undesirable, for example, if the sample is to be analyzed for dissolved gases, such as oxygen. Open containers are also unsatisfactory for collecting samples which are to be analyzed for organic matter. The reason is that a substantial amount of the volatile organic matter can dissipate into the atmosphere before the sample is tested.

Another drawback of open containers is that it is virtually impossible to obtain samples at different depths in the water body. In the field of water pollution control, therefore, there is a particular need for a device which can be used to collect samples at different depths and which will protect the sample from contamination prior to analysis.

SUMMARY OF THE INVENTION The apparatus of this invention is useful for collecting samples of various kinds of liquids, and it is particularly suitable for collecting water samples. Broadly, the structure of the present apparatus includes a platform which defines a support-member for holding one or more containers. A bar is positioned perpendicular to the platform and is fastened at its lower end to the platform. The upper end of the bar includes a fastener means.

The liquid samples are collected in one or more open end containers, which are supported on the platform during the sample collecting operation. A closure for the containers is defined by a lid member, which includes a fixed segment and a movable segment. The fixed segment is attached to the upright bar and the movable segment is hinged to the fixed segment. The movable segment can be moved to one position to close and seal the open end of the containers, and to a second position to uncover the containers. The sampling apparatus is raised and lowered in the liquid body by a lift means, such as a line, which is attached to the fas tener at the upper end of the upright bar.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view, partly in section, of one embodiment of the sampling apparatus of this invention.

FIG. 2 is a front view, partly in section, illustrating a second embodiment of the present sampling apparatus.

FIG. 3 is a front view, partly in section, of one form of a sample container and closure member which may be used in this invention. In FIG. 3 the closure member is shown in an open position within the container.

FIG. 4 is a view similar to FIG. 3, but with the closure member being shown in a closed position within the container.

DESCRIPTION OF A PREFERRED EMBODIMENT a means for collecting the liquid sample. For receiving liquid, each container 12 has an open end, preferably the upper end, as shown herein.

A rigid bar 13 is positioned perpendicular to platform 11, with the lower end of the bar being fastened to the platform at a central position on the platform. The

. upper end of bar 13 is defined by a ring member 14.

Ring 14 provides a fastener for attaching a lift means to the apparatus 10, for raising and lowering the apparatus in a liquid body. As shown in FIG. 1, the lift means is provided by a line 15, which is fastened at one end to the ring 14.

The containers 12 are held in place on platform 11 by a clamping bar 16. Basically, the clamping bar 16 is a horizontal bar which is fastened at its center to the upright bar 13. Attached to opposite ends of the bar 16 are ring straps 17, which clamp around the containers 12. Means for closing the containers 12 is provided by a lid member, indicated generally by numeral 18. Lid 18 is made up of a fixed segment 18a and one or more movable segments 18b. The fixed segment 18a is secured to bar 13 and the movable segments 18b are hinged to the fixed segment.

The movable segments 18b are held in sealing contact with'containers 12 by a hold-down member. The hold-down member includes a flat block 19, with a guide member 20, which is fastened to the top side of block 19. The block 19 and guide 20 have central openings therein, which enable the hold-down member to be slidably mounted on bar 13. Fastened to the top side of guide 20 is a line 21. The free end of line 21 passes through an upper guide member 22, which is mounted on bar 13. Line 21 is used for moving the hold-down member upwardly or downwardly on bar 13.

To illustrate the practice of the invention, a typical operation of the apparatus of FIG. I in collecting a liquid sample will now be described. One use of the sampling device would be to obtain a water sample from a stream, such as a creek or a river. In this case the apparatus 10 is lowered into the stream with line 15 to the desired depth at which the sample is to be obtained. Once the apparatus reaches the desired depth, the operator pulls line 21 upwardly a short distance.

Pulling up on line 21 causes the hold-down block 19 to slide upwardly on bar 13 and thus release the hinged segments 18b from contact with the containers 12. The hinged segments 18b, which are made of a buoyant material, will then pivot upwardly so that the containers 12 can fill with water- After allowing a few seconds for the containers to fill with water, the operator releases line 21, so that block 19 will slide down against the hinged segments 18b and close the filled containers 12. The apparatus is then pulled out of the stream and the filled containers are sealed with stoppers or caps for transporting the samples to the analytical lab.

Shown in FIG. 2 is a second embodiment of a liquid sampling device, indicated generally by numeral 23. Apparatus 23 is made up of several parts which are similar in construction and operation to the sampling apparatus 10 of FIG. 1. Specifically, the apparatus 23 includes a platform support member 24, for holding one or more open-end sample containers 25. A rigid, perpendicular bar 26 is fastened at its lower end to platform 24.

The upper end of bar 26 is defined by a ring member 27. Means for raising and lowering the apparatus 23 in a liquid body are provided by line 28, which is fastened to ring 27. Containers are held in place on platform 24 by a clamping bar 29. Clamp unit 29 is basically defined by a horizontal bar which is fastened at its center to the upright bar 26, and ring straps 30, which are attached to opposite ends of the bar. The straps 30 clamp around the neck of the containers 25 to secure the containers.

The closure for containers 25 is provided by a lid member indicated generally by numeral 31. Lid 31 includes a fixed segment 31a, which is fastened to bar 26, and one or more movable segments 31b, which are hinged to the fixed segment. The underside of hinged segments 31b includes a knob portion 310, which provides a stopper for sealing the open end of the containers 25. A float segment 31d, which is fabricated of a buoyant material, is attached to the outer edge of each of the movable segments 31b.

ln collecting the water sample, the operation of apparatus 23 is essentially the same as that of apparatus 10 of FIG. 1. The major difference in the two devices is in the operation of the container closures. For example, when the sampling device 23 is lowered into a body of water, such as a stream, the movable segments 31b are allowed to float freely, so that the containers 25 will fill with water. Thereafter, the operator allows a few seconds for water to fill the containers and then pulls upwardly on line 28 to bring the apparatus 23 to the sur- -face. As the apparatus 23 is pulled upwardly in the stream, the resulting pressure of the water forces the hinged segments 31b down against the containers 25, so that the knobs 31c will seal the container openings.

In FIGS. 3 and 4 is shown a sample collecting unit in which the container closure is a different structure than the closure used in the sampling devices of FIGS. 1 and 2. Specifically, the unit illustrated in FIGS. 3 and 4 comprises a sample container 32 which has a closure 33 positioned inside the container. The closure 33, which is fabricated of a buoyant material, is in the form of a ball stopper with a cone-shaped top. Referring to FIG. 3, the stopper 33 is shown in a rest position at the bottom of the container 32. The rest position is the positioned assumed by the stopper when the sample container is empty.

In FIG. 4,-the stopper 33 is illustrated in-its closed position within the container 32. To explain further, when the empty container 32 (FIG. 3) is lowered into a liquid, the buoyancy of stopper 33 will allow the stopper to rise with the incoming liquid 34 and thus seal the container neck. The cone top on the stopper 33 serves as a guide which aids the stopper to properly seat in the container neck. In the practice of the invention, the container-stopper unit shown in FIGS. 3 and 4 may be used with either of the sampling devices illustrated in FIGS. 1 and 2.

With regard to the various components of the sampling devices of this invention, the preferred materials of construction'and other characteristics will now be described. In general, the materials of construction for each component should be materials which are durable and which are chemically inert to the particular liquid body in which the sampling device is to be used. Examples of such liquids include fresh water, salt water, and other organic liquids.

Typical sample containers which may be used are open-top containers of various shapes and sizes, such as bottles, beakers, flasks, test tubes, and the like. Suitable container materials are glass, ceramics, plastic resins, and corrosion-resistant metals.

The platform supports 11 and 24 should be fabricated of relatively heavy materials, so that the

sampling devices

10 and 23 will sink fairly rapidly in the liquid body to be sampled. Suitable materials would include heavy metals, concrete, or the like. A preferred heavy metal is stainless steel, because of its durability, strength, and non-corrosive properties. The hold-down member 19 should also be constructed of a heavy material, such as a heavy metal. The upright bars 13 and 26 should be constructed of a corrosion-resistant metal, which could be either a light metal or a heavy metal.

For the various container closures of this invention, preferred materials of construction are materials which are buoyant in water and in other organic liquids. In addition, the closure material should be chemicallyresistantto the liquid environment in which the sampling device is used. Representative of materials which may be used are certain types of wood, rubber, cork, or plastic resins.

Where the sampling device is used in a water medium, the preferred container closure materials are those water-insoluble resins which have a density less than that of water. Typical materials include polymers of alkenyl aromatic monomers, such as styrene, methyl styrene, and interpolymers thereof, with open chain aliphatic conjugated dienes, such as butadiene, isoprene, acrylonitrile, alkyl acylates and methacrylates. Other suitable polymeric resins are polyolefins, such as polyethylene and polypropylene, and cellulose ethers and esters, such as ethyl cellulose and cellulose acetate.

It is also contemplated that certain polymeric materials which have a higher density than water may be used for container closure materials. To make the higher density compositions suitable for closure materials, the composition is modified during fabrication to make it buoyant in water. This can be done by forming voids in the material by techniques known to the art. Typical high density polymers which may be used include the polyamides, the polyesters, and the halogenated polymers, such as the homopolymers and interpolymers of vinyl chloride and vinylidene chloride. Other compositions which may be used are the thermoset polymers, such as phenol-formaldehyde, urea formaldehyde and the polyepoxides.

What is claimed is:

1. Apparatus for obtaining samples from a body of liquid, the apparatus including, in combination:

a platform which defines a support member for holding one or more containers;

i a bar which has an upper end and a lower end, which at least one sample container which has an open end for receiving a quantity of liquid,and which is supported on the platform when in position for receiving liquid; 3

at .least one container closure member which includes a fixed segment attached to the bar, and a movable segment which is attached to the fixed segment and which is buoyant in the liquid to be sampled, wherein the movable segment is adapted to be moved to the first position to close and seal the open end of the sample container, and to a second position to uncover the open end'of the container;

a lift means which is attached to the fastening means at the upper end of the bar, and which is adapted for raising and lowering the platform in a body of liquid.

2. The apparatus of claim 1 in which the container closure is defined by a stopper member which is positioned loosely within the sample container, which is buoyant in the liquid to be sampled, and which is adapted to close and seal the open end of the container upon filling the container with liquid.

3. Apparatus for obtaining samples from a body of liquid, the apparatus including, in combination:

ing liquid; at least one container closure member which includes a fixed segment attached to the bar, and a movable segment which is attached to the fixed segment and which'is buoyant in the liquid to be sampled, wherein the movable segment is adapted to be moved to a first position to closeand seal'the open end of the container, and to a second position to uncover the open end of the container; a hold-down member which is slidably mounted on the bar above the closure, member, which can be moved downwardly to hold the closure member in sealing contact with the sample container, and

which can be moved upwardly to release the closure member from contact with the container, and

4. The apparatus of claim 2 in which the liquid body is water, the movable segment of the closure member is fabricated of a water-insoluble resin having a density less than tlEt of water, and the platform support member and the hold-down member are fabricated of a material having a density greater than that of water.

5. The apparatus of claim 2 which includes a plurality of open-end sample containers which are supported on the said platform when in position for receiving liquid.

6. The apparatus of claim 2 in which the container closure is defined by a stopper member which is positioned loosely within the sample container, which is buoyant in the liquid to be sampled, and which is adapted to close and seal the open end of the container upon filling of the container with liquid.

Claims

1. Apparatus for obtaining samples from a body of liquid, the apparatus including, in combination: a platform which defines a support member for holding one or more containers; a bar which has an upper end and a lower end, which is fastened at its lower end to the platform, which is positioned perpendicular to the platform, and which has a fastening means at its upper end; at least one sample container which has an open end for receiving a quantity of liquid, and which is supported on the platform when in position for receiving liquid; at least one container closure member which includes a fixed segment attached to the bar, and a movable segment which is attached to the fixed segment and which is buoyant in the liquid to be sampled, wherein the movable segment is adapted to be moved to the first position to close and seal the open end of the sample container, and to a second position to uncover the open end of the container; a lift means which is attached to the fastening means at the upper end of the bar, and which is adapted for raising and lowering the platform in a body of liquid.

3. Apparatus for obtaining samples from a body of liquid, the apparatus including, in combination: a platform which defines a support member for holding one or more containers; a bar which has an upper and a lower end, which is fastened at its lower end to the platform, and which has a fastening means at its upper end; at least one samPle container which has an open end for receiving a quantity of liquid, and which is supported on the platform when in position for receiving liquid; at least one container closure member which includes a fixed segment attached to the bar, and a movable segment which is attached to the fixed segment and which is buoyant in the liquid to be sampled, wherein the movable segment is adapted to be moved to a first position to close and seal the open end of the container, and to a second position to uncover the open end of the container; a hold-down member which is slidably mounted on the bar above the closure member, which can be moved downwardly to hold the closure member in sealing contact with the sample container, and which can be moved upwardly to release the closure member from contact with the container, and a lift means which is attached to the fastening means at the upper end of the bar, and which is adapted for raising and lowering the platform in a body of liquid.

4. The apparatus of claim 2 in which the liquid body is water, the movable segment of the closure member is fabricated of a water-insoluble resin having a density less than that of water, and the platform support member and the hold-down member are fabricated of a material having a density greater than that of water.