US2059428A - Apparatus for analyzing exhaust gases - Google Patents

Apparatus for analyzing exhaust gases Download PDF

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US2059428A
US2059428A US720038A US72003834A US2059428A US 2059428 A US2059428 A US 2059428A US 720038 A US720038 A US 720038A US 72003834 A US72003834 A US 72003834A US 2059428 A US2059428 A US 2059428A
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burette
absorption chamber
frame
liquid
tube
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US720038A
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Gerald H Allen
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Allen Electric and Equipment Co
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Allen Electric and Equipment Co
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N7/00Analysing materials by measuring the pressure or volume of a gas or vapour
    • G01N7/02Analysing materials by measuring the pressure or volume of a gas or vapour by absorption, adsorption, or combustion of components and measurement of the change in pressure or volume of the remainder
    • G01N7/04Analysing materials by measuring the pressure or volume of a gas or vapour by absorption, adsorption, or combustion of components and measurement of the change in pressure or volume of the remainder by absorption or adsorption alone

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  • Second to provide an apparatus for analyzing the exhaust gases from internal combustion engines to determine the carbon dioxide content of such Second, to provide such an apparatus that is easily and simply operated without the necessity of making various volume determinations and in which the mere reading of a scale after a few simple manipulations will give a reading of the carbon dioxide content of the gas analyzed.
  • Fig. 1 is an elevational view of my apparatus.
  • Fig. 2 is a view similar to Fig. 1 with the front broken away to show the operative portions of the device.
  • Fig. 3 shows one step in the operation of the device.
  • Fig. 4 shows the next succeeding step.
  • Fig. 4A shows the valve setting following the step shown in Fig. 4.
  • Fig. 5 shows the next step in the operation of the device.
  • Fig. 6 shows the step in the operation of the device after the step shown in Fig. 5.
  • Fig. 7 shows the step in operating the device following that shown in Fig. 6.
  • Fig. 8 is a back elevational view of the ap- 35 paratus.
  • Fig. 9 is a detail view of the valve with the plate and cams removed.
  • Fig. 10 isa view of the plate and cams of the valve.
  • Fig. 11 is a view showing the operation of the cams and valve.
  • I is a rotatable frame supported on a suitable
  • On the standard 2 is a suitable stop 4 to engage stops 5 mounted on the rotatable frame and adjustable by means of screws 6.
  • the stops as shown are spaced to permit a ninety degree operation of the device 50 but may be otherwise arranged if desired.
  • the frame is an opening 1 serving as a handle and making sure that when the device is carried it will always be upright, so that liquid cannot flow from .the reservoirs.
  • Mounted on the rotatable frame I is a burette 8 having a suitable graduated scale 9. The bottom of the burette is connected to a reservoir It] by a suitable connection II.
  • the reservoir has an opening l2 opening to the atmosphere to permit the fluid l3 in the reservoir to flow to the burette as the frame is rotated through the desired angular distance. It will be seen that by rotation of the frame I in a counter-clockwise direction, as shown in Fig. 2, the liquid [3 would run from the reservoir to fill the burette as is shown in Fig. 3.
  • an absorption chamber I 4 which may be any suitable carbon dioxide absorption chamber used for the purpose of analyzing exhaust gases.
  • This frame is mounted at right angles to the burette in the embodiment of the invention illustrated and has above it a reservoir l5 containing liquid It.
  • the reservoir I5 is connected to the absorption chamber by connection I! and is so arranged in reference to the absorption chamber that when the frame is in the position shown in Fig. 2, which will be referred to as the initial position, the fluid fills the absorption chamber, and when the apparatus is rotated clockwise, as shown in Fig. 2, the fluid may flow from the absorption chamber to the reservoir, as shown in Fig. 5.
  • the reservoir I5 is provided with an opening it opening to the air. It will be seen that both reservoirs are arranged so that the rotation of the device does not empty the fluid from them.
  • the top end of the burette is connected to the gas absorption chamber by means of a tube I9.
  • a tube I9 Connected to thetube H] at a point between the burette and the absorption chamber is a T-connection 20, one leg 2i of which opens into the tube l9, another leg 22 opens to the atmosphere, and another leg 23 may be connected to a suitable source of gas to be tested, as will be later described.
  • I provide a valve which consists of a flexible tube 24 in the leg 2! and a second flexible tube 25 in that portion of the tube 19 that runs from the absorption chamber to the T-connection 20.
  • the flexible tubes 2i and 25 are mounted against a flat portion of the frame and have extending over them respectively the shoes 26 and 21, which are adapted to be forced down against the tube to pinch, but are of spring material so that they retract when there is no pressure on them.
  • a disk 29 having thereon cams 31], 3
  • and 32 are adapted to engage shoe 2'! and the cam to engage cam 26.
  • the cams are arranged on the face of the disk so that when the disk is in one position the cam 3
  • the cam 30 engages the shoe 26 to close off the leg 2
  • the cam 36 engages the shoe 26 While the cam 32 engages the shoe 2?, closing off both the absorption chamber and the T-connection 20, which, in effect, closes off the burette.
  • the disk 29 extends from the front of the apparatus and has thereon an arrow 33 to indicate to the operator the position of the cams.
  • I provide an opening 34 through which the operator of my apparatus can ascertain the level of the liquid in the absorption chamber when the device is at its initial position.
  • the burette 6 is visible from the front of the apparatus, as is shown in Fig. l, and the level of liquid l3 in the burette may be read from the front of the apparatus.
  • the leg 23 of the T-connection 26 may be connected by tube 35 to a suitable condenser.
  • 36 represents a pump for taking the exhaust gas to be analyzed through tube 3'! and passing it through tube 38 to the condenser which is here shown at 39 and consists of a cooling coil 40 connected to an upright tube 4
  • the device In operation, the device is set in position, shown in Fig. 2, with the level of liquid in the burette at zero. The adjustment can be accomplished through the set screws 6 on the stops 5.
  • the valve is then turned so that cam 3
  • the liquid I3 in the reservoir ll] flows to the burette 8 and forces any air therein out through the T-connection, as indicated by arrows.
  • the pump 36 is then started and the exhaust gas is passed through tube 35 directly across the leg 2
  • the device is then rotated back to its initial position and the liquid l3 flows from the burette 8 to the reservoir l0, sucking in the gas to be tested.
  • the valve is then turned to the position shown in Fig. 4-A and the cam 30, engaging shoe 26, closes off the T-connection and the cams 3! and 32 are clear of the shoe 2?, which opens the tube l9 between the burette and the gas absorption chamber.
  • the device is then rotated through the desired angular distance to the position shown in Fig. 5.
  • the liquid l3 from the reservoir l0 forces the gas from the burette through the tube l9 to the gas absorption chamber and the liquid I6 flows from the absorption chamber to the reservoir l5, sucking the gas into the absorption chamber where the carbon dioxide is absorbed.
  • the device is then rotated to the position shown in Fig. 6, and the level of liquid in the absorption chamber is adjusted so as to be identical with the position of the liquid level at the time of starting the test.
  • the operator can look through the opening 34 to determine this.
  • the level is indicated by the numeral 43.
  • the valve is turned so that cam 30 engages shoe 26, closing off the T-connection and the cam 32 engages shoe 2! closing off the absorption chamber.
  • the device is then returned to the initial position, as shown in Fig. '7, and the liquid level in the burette is read.
  • the burette 8 is of a straight tube type and by first adjusting the level 43 and then closing off the absorption chamber and the T-connection to close off the burette, it is possible to turn the frame back to initial position so that a reading can be taken on a straight burette.
  • the burette could be curved in form and that the calibrations thereon could be made such that the last step of closing off the burette and returning it to upright position would be unnecessary, and I do not wish to be limited to such an apparatus.
  • valve means could be utilized, or that separate valves could be used for the individual connections.
  • the T- connection is especially advantageous in that no pressure is exerted on the system by the gas passing the mouth of the T.
  • Other means could be used for getting the gas into the system without exerting a pressure thereon and I do not wish to be limited to the specific means.
  • a rotatable frame means limiting the rotation of said frame through ninety degrees, a burette held substantially vertical when the frame is in initial position, a graduated scale therefor, a reservoir connected to said burette and open to the air and having a liquid therein and so positioned that when the frame is in initial position, the burette is substantially empty of liquid, and such that when the frame is rotated through ninety degrees from said initial position the reservoir discharges the liquid into said burette to fill the same, an absorption chamber for carbon dioxide, a reservoir open to the air and having a liquid therein and connected to said absorption chamber, said reservoir being adapted to fill said absorption chamber with liquid when the frame is in initial position and to receive liquid discharged from the absorption chamber when the frame is rotated through ninety degrees from said initial position, a tube connecting said burette and said absorption chamber, a T- connection having one leg opening into said tube, one leg opening to the atmosphere, and another leg connected to a source of gas to be
  • an apparatus for analyzing exhaust gases the combination of a rotatable frame, a burette thereon, a graduated scale therefor, a reservoir connected to said burette and open to the air and having a liquid therein and so positioned that when the frame is in initial position the burette is substantially empty of liquid and such that when the frame is rotated a predetermined angular distance from said initial position the reservoir discharges the liquid into said burette to fill the same, an absorption chamber for carbon dioxide, a reservoir open to the air and having a liquid therein and connected to said absorption chamber, said reservoir being adapted to fill said absorption chamber with liquid when the frame is in initial position and to receive liquid discharged from the absorption chamber when the frame is rotated said predetermined angular distance from said initial position, a tube connecting said burette and.
  • said absorption chamber a connection opening into said tube to permit air to be discharged from the apparatus and to admit gas to be analyzed, and a manually operated valve adapted in one position of said valve to close off said absorption chamber and to leave said burette open to said connection, said valve in another position thereof opening the tube between said burette and said absorption chamber while closing off the said connection, said valve in another position thereof closing off said burette.

Description

1936- G. H. ALLEN APBARATUS FOR ANALYZING EXHAUST GASES Filed April 11, 1954. 2 SheetsSheet INVENTOR e/ a/d ff 67/617 bur TM! A TTORNEYS NOV. 3, 1936. G, ALLEN 2,059,428
APPARATUS FOR ANALYZING EXHAUST GASES Filed April 11, 1934' 2 Sheets-Sheet 2 ATTORNEY;
standard 2 pivoted on a bolt 3.
Patented Nov. 3, 1936 PATENT. OFFICE APPARATUS FOR ANALYZING EXHAUST GASES Gerald H. Allen, Kalamazoo, Mich assignor to Allen Electric & Equipment 00., Kalamazoo,
, Mich.
7 Application April 11, 1934, Serial No. 720,038
4 Claims.
The objects of this invention are:
First, to provide an apparatus for analyzing the exhaust gases from internal combustion engines to determine the carbon dioxide content of such Second, to provide such an apparatus that is easily and simply operated without the necessity of making various volume determinations and in which the mere reading of a scale after a few simple manipulations will give a reading of the carbon dioxide content of the gas analyzed.
Third, to provide such an apparatus that is cheap and simple in construction.
Further objects and advantages pertaining to details of construction and operation will appear from the detailed description to follow. A preferred embodiment of my invention is illustrated in the accompanying drawings, in which:
Fig. 1 is an elevational view of my apparatus.
Fig. 2 is a view similar to Fig. 1 with the front broken away to show the operative portions of the device.
Fig. 3 shows one step in the operation of the device.
Fig. 4 shows the next succeeding step.
Fig. 4A shows the valve setting following the step shown in Fig. 4.
Fig. 5 shows the next step in the operation of the device.
Fig. 6 shows the step in the operation of the device after the step shown in Fig. 5.
Fig. 7 shows the step in operating the device following that shown in Fig. 6.
Fig. 8 is a back elevational view of the ap- 35 paratus.
Fig. 9 is a detail view of the valve with the plate and cams removed.
Fig. 10 isa view of the plate and cams of the valve.
Fig. 11" is a view showing the operation of the cams and valve.
The. parts will be identified by their numerals of reference which are the same in all the views. I is a rotatable frame supported on a suitable On the standard 2 is a suitable stop 4 to engage stops 5 mounted on the rotatable frame and adjustable by means of screws 6. The stops as shown are spaced to permit a ninety degree operation of the device 50 but may be otherwise arranged if desired. In ,the frame is an opening 1 serving as a handle and making sure that when the device is carried it will always be upright, so that liquid cannot flow from .the reservoirs. Mounted on the rotatable frame I is a burette 8 having a suitable graduated scale 9. The bottom of the burette is connected to a reservoir It] by a suitable connection II. The reservoir has an opening l2 opening to the atmosphere to permit the fluid l3 in the reservoir to flow to the burette as the frame is rotated through the desired angular distance. It will be seen that by rotation of the frame I in a counter-clockwise direction, as shown in Fig. 2, the liquid [3 would run from the reservoir to fill the burette as is shown in Fig. 3.
On the frame, I also mount an absorption chamber I 4 which may be any suitable carbon dioxide absorption chamber used for the purpose of analyzing exhaust gases. This frame is mounted at right angles to the burette in the embodiment of the invention illustrated and has above it a reservoir l5 containing liquid It. The reservoir I5 is connected to the absorption chamber by connection I! and is so arranged in reference to the absorption chamber that when the frame is in the position shown in Fig. 2, which will be referred to as the initial position, the fluid fills the absorption chamber, and when the apparatus is rotated clockwise, as shown in Fig. 2, the fluid may flow from the absorption chamber to the reservoir, as shown in Fig. 5. The reservoir I5 is provided with an opening it opening to the air. It will be seen that both reservoirs are arranged so that the rotation of the device does not empty the fluid from them.
The top end of the burette is connected to the gas absorption chamber by means of a tube I9. Connected to thetube H] at a point between the burette and the absorption chamber is a T-connection 20, one leg 2i of which opens into the tube l9, another leg 22 opens to the atmosphere, and another leg 23 may be connected to a suitable source of gas to be tested, as will be later described. At the T-connection, I provide a valve which consists of a flexible tube 24 in the leg 2! and a second flexible tube 25 in that portion of the tube 19 that runs from the absorption chamber to the T-connection 20. The flexible tubes 2i and 25 are mounted against a flat portion of the frame and have extending over them respectively the shoes 26 and 21, which are adapted to be forced down against the tube to pinch, but are of spring material so that they retract when there is no pressure on them.
At the point 28 I pivot a disk 29 having thereon cams 31], 3| and 32 adapted to engage the shoes 26 and 21. The cams 3| and 32 are adapted to engage shoe 2'! and the cam to engage cam 26. The cams are arranged on the face of the disk so that when the disk is in one position the cam 3| engages the shoe 2! to close off the absorption chamber, leaving the T-connection 20 open through tube I9 to the burette. In another position, the cam 30 engages the shoe 26 to close off the leg 2| of the T-connection, leaving the tube 9 open to connect the burette to the absorption chamber. In another position, the cam 36 engages the shoe 26 While the cam 32 engages the shoe 2?, closing off both the absorption chamber and the T-connection 20, which, in effect, closes off the burette.
The disk 29 extends from the front of the apparatus and has thereon an arrow 33 to indicate to the operator the position of the cams. In the front of the frame I, I provide an opening 34 through which the operator of my apparatus can ascertain the level of the liquid in the absorption chamber when the device is at its initial position. The burette 6 is visible from the front of the apparatus, as is shown in Fig. l, and the level of liquid l3 in the burette may be read from the front of the apparatus.
The leg 23 of the T-connection 26 may be connected by tube 35 to a suitable condenser. 36 represents a pump for taking the exhaust gas to be analyzed through tube 3'! and passing it through tube 38 to the condenser which is here shown at 39 and consists of a cooling coil 40 connected to an upright tube 4| below which is positioned a receptacle 42 for receiving any condensate that is given off by the exhaust gases on cooling.
In operation, the device is set in position, shown in Fig. 2, with the level of liquid in the burette at zero. The adjustment can be accomplished through the set screws 6 on the stops 5. The valve is then turned so that cam 3| closes off the absorption chamber and the frame is rotated through ninety degrees, or any desired number of degrees, to the position shown in Fig. 3. The liquid I3 in the reservoir ll] flows to the burette 8 and forces any air therein out through the T-connection, as indicated by arrows. The pump 36 is then started and the exhaust gas is passed through tube 35 directly across the leg 2| of the T-connection 20, discharging to the atmosphere through the'leg 22. The device is then rotated back to its initial position and the liquid l3 flows from the burette 8 to the reservoir l0, sucking in the gas to be tested. The valve is then turned to the position shown in Fig. 4-A and the cam 30, engaging shoe 26, closes off the T-connection and the cams 3! and 32 are clear of the shoe 2?, which opens the tube l9 between the burette and the gas absorption chamber. The device is then rotated through the desired angular distance to the position shown in Fig. 5. The liquid l3 from the reservoir l0 forces the gas from the burette through the tube l9 to the gas absorption chamber and the liquid I6 flows from the absorption chamber to the reservoir l5, sucking the gas into the absorption chamber where the carbon dioxide is absorbed. Leaving the valve in the same position, the device is then rotated to the position shown in Fig. 6, and the level of liquid in the absorption chamber is adjusted so as to be identical with the position of the liquid level at the time of starting the test. The operator can look through the opening 34 to determine this. The level is indicated by the numeral 43. When the balancing is completed, the absorbed gas having reduced the volume of gas enclosed in the apparatus, the liquid level in the burette will be considerably higher than originally. This is indicated at 44. When this has been accomplished, the valve is turned so that cam 30 engages shoe 26, closing off the T-connection and the cam 32 engages shoe 2! closing off the absorption chamber. The device is then returned to the initial position, as shown in Fig. '7, and the liquid level in the burette is read. The burette 8 is of a straight tube type and by first adjusting the level 43 and then closing off the absorption chamber and the T-connection to close off the burette, it is possible to turn the frame back to initial position so that a reading can be taken on a straight burette.
It will, of course, be understood that the burette could be curved in form and that the calibrations thereon could be made such that the last step of closing off the burette and returning it to upright position would be unnecessary, and I do not wish to be limited to such an apparatus.
It will be understood that other valve means could be utilized, or that separate valves could be used for the individual connections. The T- connection is especially advantageous in that no pressure is exerted on the system by the gas passing the mouth of the T. Other means could be used for getting the gas into the system without exerting a pressure thereon and I do not wish to be limited to the specific means.
I have described the apparatus for rotation through a ninety degree arc. It will be apparent to those skilled in the art that another are could be used and that the result could be obtained in an equally satisfactory manner.
I have shown and described my apparatus in the embodiment preferred by me, but wish to claim the same broadly as well as specifically, as pointed out in the appended claims.
Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:
1. In an apparatus for analyzing exhaust gases, the combination of a rotatable frame, means limiting the rotation of said frame through ninety degrees, a burette held substantially vertical when the frame is in initial position, a graduated scale therefor, a reservoir connected to said burette and open to the air and having a liquid therein and so positioned that when the frame is in initial position, the burette is substantially empty of liquid, and such that when the frame is rotated through ninety degrees from said initial position the reservoir discharges the liquid into said burette to fill the same, an absorption chamber for carbon dioxide, a reservoir open to the air and having a liquid therein and connected to said absorption chamber, said reservoir being adapted to fill said absorption chamber with liquid when the frame is in initial position and to receive liquid discharged from the absorption chamber when the frame is rotated through ninety degrees from said initial position, a tube connecting said burette and said absorption chamber, a T- connection having one leg opening into said tube, one leg opening to the atmosphere, and another leg connected to a source of gas to be analyzed, and a valve adapted in one position to close off said absorption chamber and to leave said burette open to said T-connection, said valve in another position opening the tube between said burette and said absorption chamber while closing off the said T-connection, said valve in another position closing off said burette, said valve comprising a flexible section in the tube between the T- connection and the absorption chamber, a flexible section in the arm of said T-connection communicating with said tube, a rotatable disk, and a plurality of cams on said disk adapted to engage and pinch said flexible sections.
2. In an apparatus for analyzing exhaust gases, the combination of a rotatable frame, a burette thereon, a graduated scale therefor, a reservoir connected to said burette and open to the air and having a liquid therein and so positioned that when the frame is in initial position the burette is substantially empty of liquid and such that when the frame is rotated a predetermined angular distance from said initial position the reservoir discharges the liquid into said burette to fill the same, an absorption chamber for carbon dioxide, a reservoir open to the air and having a liquid therein and connected to said absorption chamber, said reservoir being adapted to fill said absorption chamber with liquid when the frame is in initial position and to receive liquid discharged from the absorption chamber when the frame is rotated said predetermined angular distance from said initial position, a tube connecting said burette and. said absorption chamber, a connection opening into said tube to permit air to be discharged from the apparatus and to admit gas to be analyzed, and a manually operated valve adapted in one position of said valve to close off said absorption chamber and to leave said burette open to said connection, said valve in another position thereof opening the tube between said burette and said absorption chamber while closing off the said connection, said valve in another position thereof closing off said burette.
3. In an apparatus for analyzing exhaust gases, the combination of a rotatable frame, a burette thereon, a graduated scale therefor, an absorption chamber for carbon dioxide, means connect ing the burette and the absorption chamber, means for forcing air from said burette when the frame is rotated a predetermined angular distance from its initial position and for sucking the gas to be tested into said burette when the frame is rotated to its initial position, means for sucking gas to be analyzed from the burette to the absorption chamber when the frame is rotated from initial position said predetermined angular distance and for expelling gas therefrom when the frame is rotated back to its initial position, and manually operated means adapted in one position of said means to close off said absorption chamber and to leave the burette open, said means in another position thereof opening the connection between the burette and the absorption chamber, said means in another position thereof closing off the burette.
4. In an apparatus for analyzing exhaust gases, the combination of a rotatable frame, a burette thereon, a graduated scale therefor, an absorption chamber, means connecting the burette and the absorption chamber, means for forcing air from said burette when the frame is rotated at predetermined angular distance from its initial position and for sucking the gas to be tested into, said burette when the frame is rotated to its initial position, means for sucking gas to be analyzed from the burette to the absorption chamber when the frame is rotated from initial position said predetermined angular distance and for expelling gas therefrom when the frame is rotated back to its initial position, and manually operated means adapted in one position of said means to close off said absorption chamber and to leave the burette open, said means in another position thereof opening the connection between the burette and the absorption chamber.
GERALD H. ALLEN.
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