JPH0454171B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to fluid samplers and has particular relevance to sampling for selected components of gases, primarily air. be. In particular, the present invention relates to an electrical control device for flow rate in the invention "Fluid Sample Sampler" (Japanese Unexamined Patent Publication No. 111738/1982), which is an invention based on the original patent application.

BACKGROUND OF THE INVENTION Typically, the fluid sample collection to which the present invention pertains involves the collection of toxic components of the air within a facility, or the collection of chemical wastes, per the Occupational Safety and Protection Act (OSHA) in the United States. Air samples are collected in areas such as Love Central in the United States, which are often polluted. This type of sampling is typically carried out by a sampler that is carried or "worn" by a person working in air containing components harmful to health. It will be done. This sampling can take place either through the work of the person involved in the work or during measurement time intervals. Sometimes it is also desired that the air flow through the sampler be restricted.

Some samplers include a pump that pumps air through a channel containing a collector or processor, and the device collects and/or measures the concentration of harmful components. The processor is usually
It is placed inside the inlet (suction side) to the pump. The processor may also be the outlet (pressure side), especially in the case of chemical bag collection. The collected components are gas, steam, or
It is a solid particle. The sampled air needs to be filtered before dirt or dust enters the pump. The pump is protected by a so-called pump filter, through which the pumped air flows as it is drawn into the groove. The function of the pump filter is to protect the pump from this dirt and dust. This filter, whose pores become clogged with dust during operation, gradually increases the suction pressure of the pump. Moreover, unless the effect of filter clogging on the flow is removed, it will gradually increase the resistance to the flow of air pumped through the grooves and reduce the speed or flow rate of the air flow. do. Flow may also fluctuate for reasons other than dust accumulation on the filter. According to the prior art, a differential pressure switch is placed in the outlet of the flow passage to suppress air flow fluctuations. This pressure switch responds to the difference between the pressure within one chamber and the pressure outside the chamber.
This chamber is connected to the external area via a needle valve. The pressure switch opens and closes in response to pulsations produced by the pumping action. One disadvantage of this measure is that repeated actuation of the pressure switch causes fatigue to its linkage.
Another important disadvantage is that traces of dirt, such as dust, can interfere with the operation of the needle valve and provide a satisfactory, stable, and reliable response to pressure pulsations in the flow groove of the pressure switch. It is to prevent it.
Another disadvantage is that additional suction power is required to maintain the pressure required for detection, but this is because the increase in pressure This is because it is absorbed.

SUMMARY OF THE INVENTION One object of the present invention is to overcome the shortcomings of the prior art and provide fluid sampling methods that do not fatigue moving parts and maintain a substantially constant flow of the fluid being sampled. There is a problem in obtaining a device, and in particular a control device therefor.

SUMMARY OF THE INVENTION One feature of the present invention is that fluctuations in fluid flow through a fluid sampler result in a differential pressure, i.e., a pressure difference between the outlet from the pump and the inlet to the pump. This is caused by varying the load on the motor that drives the pump (hereinafter referred to as "ΔP").

According to the invention, the motor is configured to maintain a substantially constant fluid flow through the fluid sampler in response to its load, i.e., ΔP, throughout its operating flow range. controlled.

The fluid sampler has an electronic solid-state controller that includes a current compensation circuit and
It includes a battery check, a low battery voltage indicator, a low current indicator, a timer, and an on/off switch.

The current compensator adjusts the constant air flow from the pump to any pre-adjusted flow range of the sampler,
Typically, doses are given over a range of between 500 and 4 ml per minute.

The current compensation circuit is useful for pump linearity in conjunction with preloaded valves.

The current compensation circuit includes a sensing resistor mounted in the motor leg that provides a voltage signal proportional to the motor load current to the power supply;
As such, it also adjusts the motor voltage proportionally to the pump load curve, thereby typically adjusting the flow rate between 0 and 0 of the water column (positive or negative) over the entire range of operation. Provides relatively constant flow over a 508mm backpressure range.

An additional feature of the invention is that in the unlikely event that the pump exceeds its operating range (suction or exhalation)
If controlled, automatic pump shutoff and failure indication.

The present invention also includes a visual battery check indicator which is actuated by a push test switch to detect an overcharged condition of the battery. The battery is typically a Nikkad battery. A visual indicator is provided for battery capacity for a minimum of 8 hours of sample collection at any flow rate within the capacity of the sampler. Additionally, a visual low voltage indicator is provided which indicates if the voltage to the electronic control drops below the minimum voltage required to properly operate the sampler. ,Operate. At the same time the low voltage indicator is activated, the pump and timer are stopped and the indicator is latched on. The timer is
Indicates the number of hours of operation before failure and then stops.

Also, a low flow indicator detects a drop in flow conditions, stops the pump and timer, and activates the low flow indicator after an appropriate time delay that is a function of the overload condition.

A presettable electronic timer indicator is also provided which indicates the number of hours of operation and
Typically, 10 minute time intervals can be preset to stop the pump, up to 990 minutes (16.5 hours). Timing is set by two 10 position switches, the first switch giving a 10 minute time interval and the second switch giving a 100 minute time interval. The electronic timer indicator is cleared until the push test button is activated. The clock controlling the timer automatically stops when activated by any of the above fault conditions (such as no sample flow or low battery voltage). This feature allows the user to always achieve true collection of the sample, even if the entire sampling period is not realized.

Embodiments Hereinafter, the present invention will be described in detail based on the accompanying drawings showing embodiments thereof.

The apparatus shown in the figure is a compressed air assembly, i.e. a processing unit 21 for air or other gases.
(hereinafter also referred to as the "compressed air assembly") (see Figures 1 and 4), a battery pack 23, a board 25 containing a timing circuitry on a printed circuit (see Figure 5), and a printed circuit board 25. Upper control network (see Figure 6)
and a disk 27 containing a fluid sampler. The fluid sampler 20 includes a front case 2
9 and a rear case 31. Battery pack 23 is a cartridge containing batteries 33 in a container 35. The front case 29 is placed on the left hand (as seen in Figure 1),
They each include a bar-shaped recess 37 and a slot 39 on the right hand. Timing network 25 and control network 27 include interconnected conductors (see FIGS. 5 and 6). Both network boards 25 and 27 are vertically (as viewed in FIG. 1) coextensive. The planar unit formed by these two network boards 25 and 27 rests on a boss (not shown) extending from the back of the recess 37. The battery pack 23 is adjacent to both circuit boards 25 and 27, and also has battery sockets 41 and 43.
are connected to terminals or pins 48 and 47 (FIG. 6) of control network board 27. Name tag 49 is
It is placed in the recess 37 and in contact with it. The cover 51 has a tongue 53 that extends into the recess 37 flush with the outer rim of the front case 29 and adjacent the name tag 49. are doing. The cover 51 has a tongue 53 which is located in the recess 37.
engages a cooperating groove (not shown) in the top of the.

Compressed air assembly 21 is supported in a right-hand (as viewed in FIG. 1) compartment of front case 29. A flow meter 55 in compressed air assembly 21 is arranged opposite slot 39. The window 57 is between the flowmeter 55 and the slot 39, and the frame of the window 57 is
It extends into slot 33 abutting the border of slot 39 .

The top of the compressed air assembly 21 has a hollow boss 6
1,63,65. insert 67
extend over the bosses 61, 63, 65 and are arranged on the top. Insert 67 has a tongue 69 that engages a groove (not shown) in the edge of slot 71 in the top of front case 29. Rear case 31 surrounds compressed air assembly 21 and its inner edge engages the inner edge of front case 29 . The inner edge of the rear case 31 is provided with a tongue 73 which engages in a slot (not shown) in the inner edge of the front case 29. Rear case 31 is secured to front case 29 by screws 75 passing through bosses in its four corners. The rear case 31 has a slot 77 in its top, in which the case 31 engages the insert 67. The inner edge of slot 77 has a groove 79 that connects to a tongue (not shown) in insert 67. The rear case 31 has a slot 61 in its side which surrounds the inner boundary of the pump filter assembly 83.

Belt clip 85 is secured to rear case 31 by rivet 87;
7 is the hole 89 near the left hand edge of the rear case 31
, and is caulked to the rear case 31. Belt clip 85 extends beyond the left hand edge of rear case 31 and bounds between it and front case 29 a vertical space or pocket for receiving battery pack 23.

The manner in which fluid sampler 20 is assembled is disclosed in the specification and drawings of the original patent application. The dimensions of a typical fluid sampler 20 are also disclosed in the specification and drawings of the original patent application.

The compressed air assembly 21 (FIG. 1) includes a ROTOMETER 55 and a pump filter 83, as well as a pump assembly 9, as shown in FIG.
3, damper assemblies 95, 97 and regulator 99 (FIG. 4). Pump assembly 93, damper assemblies 95 and 97, and regulator 99 are stacked and secured together by screws (third,
Figure 4). In the stack, the pump assembly 9
3 between the top plate 114 and the upper valve plate 120 and between the bottom plate 116 and the lower valve plate 12 of the pump assembly 33.
gaskets 98 and 100 (third,
Figure 4). Each assembly 93, 95, 9
7,99 are countersunk holes 104 together
is held in by screws 102 (FIG. 3). Pump assembly 93, damper assembly 95, 97
and regulator 99 have coextensive apertures which, when each of these assemblies 93, 95, 97 and regulator 99 are stacked, form suction groove 106. and discharge grooves 108 (FIG. 4) through which air is pumped and discharged, respectively, into compressed air assembly 21 by pump assembly 93. Further, each of the assemblies 93 and 9 adjacent to each other of the suction groove 106 and the discharge groove 108
5, between each pair of 95 and 97 and 97 and regulator 99 are compressed O-rings 110 and 112.
Sealed by etc.

The pump assembly 93 (FIG. 3) is attached to the upper valve plate 12.
In addition to the lower valve plate 122, the top plate 114, the bottom plate 116, and the gaskets 98, 100, the main body 149 has a rectangular parallelepiped shape. This body 149 has a horizontal recess 151 into which an eccentric drive 153 extends. This driving body 153 includes a motor 155 and a motor 155.
It includes an eccentric 157 driven by. The eccentric 157 has a pin 159 that is eccentrically arranged.
is rotatable in a bearing 161. The motor 155 has a set screw 1 in the recess 151.
63.

Body 149 also has a vertical bore 165 extending through the top and bottom of body 149;
Further, this inner hole 165 communicates with the depression 151. A diaphragm assembly 167 is mounted within the vertical bore 165 . The diaphragm assembly 167 includes a yoke 168, upper and lower diaphragms 169, 171, and diaphragm retainers 173, 175. Diaphragms 169 and 171 are connected to end plate 17 of yoke 168.
7 and 179 by retainers 173 and 175. Diaphragms 169 and 171
are placed in annular recesses 181 (FIG. 3) in the top and bottom of body 149. The diaphragms 16, 171 are held within this recess 181 by the upper and lower valve plates 120, 120. The pin 159 and the bearing 161 are connected to the yoke 16
It is placed in the opening in 8 and is adapted to come into contact with the inner circumferential surface of the opening. Exen 157
is rotated by the motor 155, the yoke 168 via its eccentric pin 159 is moved upwardly and downwardly, and the diaphragm 1 correspondingly moves upwardly and downwardly.
69 and 171 are deflected upward and downward in opposite phases. Main body 149 and upper and lower valve plates 12
0 and 122, there is an O-ring seal 183 (Figs. 3 and 4) at the joint of the suction groove 106 and the discharge groove 108 formed therein.
These O-ring seals 183 are connected to the suction groove 1
06 and the discharge groove 108 are sealed against the inner hole 165.

Upper valve plate 120 has a circular opening opposite and sealed by diaphragm 169, and diaphragm 169 and upper valve plate 120 define a filling chamber 187 (FIG. 4) at the opening. is formed. The base of this filling chamber 187 in the upper valve plate 120 is formed by a circular recess or valve seats 189 and 191 (the fourth
Figure). Located within each recess is a prestressed valve seat 193 and 195 (best shown in FIG. 4). Each valve plate is secured in a recess by a retainer 197 and is prestressed;
is the spacer 198 (fourth) on the opposite side of the valve plate.
(Fig.) is engaged. In the valve seats 189 and 191 there are holes 199 and ) 201. hole 199
connects the filling chamber 187 to the suction groove 106;
Hole 201 connects fill chamber 189 to discharge channel 106 . This connection is through hooked slots 203 and 205 in the upper valve plate 120. Valve plate 193 is positioned to open its valve seat 189 as diaphragm 169 moves downwardly, creating a partial vacuum in fill chamber 187 . Against this tendency of the diaphragm 169, the other valve plate 195 is forced into tighter engagement with its valve seat 191. Conversely, when diaphragm 169 is moved upwardly and the pressure in fill chamber 187 increases, valve plate 195 opens and valve plate 193 closes more tightly.

The lower valve plate 122 likewise has a circular hole 207 (FIG. 3), which is sealed by a diaphragm 171 to form a fill chamber 209 (FIG. 4).

The base of the filling chamber 209 has disc-shaped valve seats 211 and 213, and a valve plate 2 is placed above them.
15 and 217 are placed. Valve seat 211,2
13 connects the filling chamber 209 to the slot 223 (fourth
It has holes 219 and 221 which are connected to the suction groove 106 through a slot 225 (see FIG. 1) and to the discharge groove 108 through a slot 225. Main body 149
are connected to the suction groove 106 and the discharge groove 108 through oval slots 226 and 228 that are sealed by O-rings 183. Pressure switch S3 (Figs. 4 and 6)
He has been suspended from 16. This pressure switch S3
communicates with the suction slot 223 on one side and with the discharge slot 225 on the other side to remove excess vacuum on the suction side and excess vacuum on the discharge side. In response to both pressures, latch 4U3 (FIG. 6) is actuated to shut down operation under conditions requiring shutdown, such as when a suction or discharge tube becomes clogged. The structure and operation of the damper assemblies 95, 97 and the regulator 99, as well as their cooperation with the pump assembly 93, can be clearly understood by referring to the specification and drawings of the original patent application. can be done.

The compressed air assembly 21 is electrically controlled by a timer board 25 and a control board 27. The actual circuitry that makes it work satisfactorily is, for the timer,
The control circuit is shown diagrammatically in FIG. 5 and, for the control circuit, in FIG. 6, respectively. In these networks, integrated circuits are included for the most part. For example, operational amplifiers U1 to 3U1 (FIG. 5) fall under this category. In addition, the name is the 5th
Although not written in Figures 6 and 6, the actual values of the parts are shown. When the size of the capacitor, that is, the numerical value, is indicated only by numbers, for example, in FIG. 5, for the capacitor C1, . If it says 001, the capacity is in micro microfaults. The size of the micro microfarad is
It is named as such. The magnitude of the resistance is
Ohms, if a "K" is added to the number, it is 10 million ohms. For the most part, the magnitudes of the input and output signals are mostly represented numerically as "1" or "0" instead of "high voltage" and "low voltage." 1 is 2.5V and higher than 2.5V, 0 is . 4V and. Lower than 4V. However, sometimes an intermediate state of about 2.5V exists,
In this state, certain operations are possible. Control panel 2
The output above 7 and the input to the timer board 25 are:
It is given a name such as TIM. The bar above the input, e.g., has 0 applied to it,
It means to bring about the necessary action. If there is no bar, eg INH, a 1 is applied, which means that the required action, in this case a reset, occurs. Since the fluid sampler container consists of electrical insulation, grounding is provided by conductors on printed circuit boards 25 and 27. The power ground is represented, as usual, by three lines GD of decreasing length. Digital grounding is represented by the fork-shaped symbol GRD.

The device shown in FIG. 5 includes a transmitter OSC,
The frequency divider typically includes a 14 stage (divided by 10 ¹⁴ ) frequency divider, a counter U3 and an indicator U4. The oscillator OSC includes an operational amplifier U1, a calibration resistor R6, a resistor RP1 and a capacitor C1. The period of this oscillator OSC is typically about 366 microseconds.
The output of the oscillator OSC is applied onto the clock input CK of the frequency divider U2. At its output Q14, frequency divider U2 produces a low frequency signal, typically one cycle every 6 seconds. This signal is the clock input of counter U3.
Applied on top of CK. The number of counts produced by counter U3 is preset by selection switches S1 and S2. Selection switch S1 is 100,
Selection switch S2 counts 10. Selection switches S1 and S2 operate via diodes CR1 to CR8. Counter U3 includes a register and a comparator (both not shown). As mentioned above, the time limit is 990 minutes, i.e.
Set at 10 minute intervals during the 16.5 hour duration.

At the beginning of operation when power is first applied with switch 1S1 (FIG. 6) set on, the input LR of counter U3 is connected to capacitor C3.
It becomes 1 from the 5V supply via (Fig. 5). As capacitor C3 charges up, input LR is 2.5V
becomes. Finally, capacitor CR is sufficiently charged and input LR becomes 0. When input LR becomes 1 (5V), the numbers set by switches S1 and S2 are loaded into the register of counter U3. The reset output is set to 0,
Counting starts after input LR reaches 2.5V.
This counting continues with input LR at or below 2.5V. When the comparator finds the count equal to the input, EQ goes to 0, latch 1U3 (Figure 6) is set, and INH (6
Make 1 in Figure). The output of amplifier 1U1 becomes 0, stopping the oscillator OSC and stopping counting. Motor 155 (FIG. 6) is also stopped. In each latch, such as latch 1U3 (FIG. 6), the setting created by a 0 at is latched in, and after the 0 is released from, a 0 is placed above to reset the latch. It will remain latched in until it is applied.
With input LR at 1 at the start, display U4 is emptied. The signal above TST produced by closing switch 1S2 (Figs. 2 and 6) is
Activate indicator U4. Output a of counter U3
-g and inputs a-g of indicator U4, an indication is applied from counter U3 onto indicator U4. The outputs D0 to D3 of the counter U3 are displayed on the display U
The displayed digits are transferred via the 4 inputs D0 to D3. Output D3 is the most important number among these outputs, and output D0 is the least important number. Decimal point is TST, operational amplifier 2U
1 and 3U1. When the output D1 is 1, there is no decimal point. When the output D1 is at 0, there is a decimal point.

FIG. 6 shows the motor controller MC for the motor 155 by a dashed line. The remainder of FIG. 6 shows the indication and protection circuitry. 6th
The device shown includes a regulator 1U2, which produces a reference voltage at its output. Typically the output is 2.6V for any battery voltage above 4.3V. A reference voltage of 2.6V is applied to selected points in the circuit shown in FIG.

Motor controller MC is responsive to the load on motor 155 as air is pumped through the compressed air system by pump assembly 93 (FIG. 3) and increases the air flow, i.e., l/min. , or ml
is maintained constant. In this motor controller MC. Motor 155 is powered via transistor Q1. The motor current is the battery 33
(Figure 1) In the circuit extending from the +5V terminal, the emitter and collector of transistor Q1,
It flows to ground via the motor 155 and resistor R11. The current through resistor R11 is substantially equal to the motor current. Filters R12-C4 introduce a delay into motor controller MC and transistor Q
1 to prevent unwanted tripping of the overcurrent detection circuit. A capacitor 1C3 across the motor 155 suppresses brush noise. The device is energized by placing switch 1S1 in the ON ("on") position. With switch 1S1 in the OFF ("off") position, capacitor C4 discharges to ground. Transistor Q1 is controlled by operational amplifier 4U1, and the output of operational amplifier 4U1 is connected to the base of transistor Q1 via resistor R7. A resistor R6 between the emitter of transistor Q1 and the output of operational amplifier 4U1 ensures that when transistor Q1 is to be turned off, it is completely turned off. Transistor Q1
There is a feedback network between the collector of and the positive input (pin 5) of operational amplifier 4U1.
This network includes a resistor R8 and a network R4, R2
3 and R5. Resistor R23 is a thermistor, and its resistance varies exponentially with temperature. Resistor R4 linearizes the response of thermistor R23. Networks R4, R23 and R5
changes the resistance in proportion to the temperature change, and motor 1
55 to compensate for variations in resistance that vary with temperature of the copper. Capacitor C2 is the motor controller MC
Introducing a delay of 0.3 seconds in the response of the controller MC to load variations, i.e., airflow variations. Networks R8, R4, R5, R23 set the gains of amplifier units 4U1-Q1.

Control for the amplifier unit is provided by network 1R.
1, R9, 1R2, R22, R11 and R3 from the 2.6V output of 1U2 to operational amplifier 4.
Applied above the negative input of U1. The voltage drop across resistor R11, which measures the motor current, is compared to the voltage induced across resistors 1R1, R9, 1R2, R22 and R3. The resistor R3 is
Adjusting the desired air flow, resistor 1R1
The resistor 1R2 is adjusted for correction at the high flow end and for correction at the low flow end.

The circuit disclosed herein can track changes in current without becoming unstable. When the current changes, the voltage drop across resistor R11 changes, correcting for the change in current by changing the voltage across the motor 155. If the current is increased above the regulated magnitude, decreasing the voltage across the motor 155, and if the current is decreased below the regulated magnitude; The voltage drop across resistor R11 increases, causing the terminal voltage to increase.

A comparator in counter U3 (FIG. 5) signals the end of counting and when there is a zero above, the count entered is equal to the count in the preset register and there is a zero above. . Latch U3 is set to the input and a 1 is placed on the output Q. The current flows through the light emitting diode (LED) 1CR4 and also flows through the resistors R4 and RR23 to ground. operational amplifier 4
There is a 1 above the positive input 5 of U1. motor 15
The current through 5 is cut off and pump 93 stops pumping. A light in light emitting diode (LED) 1CR4 seen by the driver indicates the end of counting.

For normal operation of the motor 155, the resistor R
The current through 11 is no greater than some predetermined magnitude, typically 200 milliamps. Note that this magnitude has been assumed for the purpose of illustrating the operation of the apparatus shown in FIG. 6 in the case of excessive motor current. Based on this assumption, the voltage on pin 10 of operational amplifier 5U1 is approximately 0.3V. Even if
If resistor R11 draws more than 200 milliamps, the voltage applied across resistor R12 onto pin 9 of operational amplifier 5U1 is
Exceeding 0.3V, 0 on the output of operational amplifier 5U1 (pin 8) and on the input of latch 2U3.
There is. Above the Q output of latch 2U3 and conductor 30
Above the 1 is a 1 via a diode 1CR1. Diode 1CR1 is activated and indicates an overcurrent. 1 is on conductor 303 and stops motor 155. There is also a 1 on the output terminal INH, ie, the inhibit gate. Transmitter OSC
is disabled (FIG. 5), and counting by counter U3 is stopped. Instructions for counting before the transmitter OSC is disabled are available and give information on how long the sampler was activated before an overcurrent occurred.

Three conditions cause the output of amplifier 6U1 to be zero. 1. The voltage of battery 33 drops below 4.3V. This condition is monitored by a voltage divider including resistors R48, R19, and R20. Typically, these resistors apply a voltage of 2.6V or more onto pin 12 of operational amplifier 6U1. If the voltage of the battery 33 drops to about 1.0V or less,
The output of 6U1 becomes 0 and latch 4U3 is set. Light emitting diode (LED) 1CR2 is energized and connected to conductor 301, conductor 303 and output terminal.
1 is applied to INH, stopping the motor 155,
De-energize the transmitter OSC (Figure 5).

2 If transistor Q1 is unable to supply sufficient current to satisfy the circuit requirements. For normal operation, the output of amplifier 4U1 (pin 7) is approximately 1.9V. Current flows through the emitter and base of transistor Q1.
The drop across diode 1CR5 is approximately 0.7V, so pin 12 of operational amplifier 6U1
It is 2.6V (1.9+0.7)V. Operational amplifier seat 6U1
There is a 1 above the output of . If the voltage at the output of operational amplifier 4U1 is below 1.9V, diode 1CR5 conducts and pulls pin 12 of operational amplifier 6U1 below 2.6V;
There is a 1 on output Q of latch 4U3, conductors 301 and 303 and output INH, stopping motor 155 and transmitter OSC).

3 Operation of pressure switch S3 In this case, pin 12 of operational amplifier 6U1
becomes 0, the output Q of operational amplifier 4U3 becomes 1, and motor 155 and oscillator OSC are stopped.

Network R24-C8 is a delay network that blocks surges from trip latch 4U3.

Latch 3U3 operates to reset the device at the beginning of operation. Normally, the SET input is grounded and the output is 1. The electricity is
In operation when first applied, capacitor C5 acts as a shorting piece and resistor R5
becomes. Latch 3U3 is reset and its output becomes zero. 0 on conductors 305 and 307
There is. Latches 1U3, 2U3 and 4U3 are reset and there is also a zero on the output, resetting the timer.

At full battery voltage, ie 5.3V, voltage divider R48, R19, R20 applies a higher voltage of 2.6V or more on pin 2 of amplifier 7U1. The output of this amplifier 7U1 becomes 0. When test switch 1S2 is activated, current flows through diode 1CR3, indicating that the current is fully charged. Also 5V above the output TST
There is. 2.5V is applied to the input LR of the counter U3 via the resistor R8 (Fig. 5), and the indicator U
Can do 4.

Although preferred embodiments of the invention have been described above, many modifications thereof are possible. Therefore, it should be understood that the present invention is not limited to this example.

Effects of the Invention The present invention, having the structure and operation described above, overcomes the drawbacks of the prior art and provides a substantially constant flow of the fluid being sampled without tiring moving parts. The present invention provides a fluid sampler that can be maintained at high temperatures.

[Brief explanation of the drawing]

FIG. 1 is a perspective view without parts showing one embodiment of the present invention, FIG. 2 is a front view of the embodiment of FIG. 1 with the upper cover of the name tag removed, and FIG. FIG. 4 is a partially schematic longitudinal sectional view of the compressed air assembly; FIG. 5 is an exploded perspective view of the pump incorporated in the embodiment shown; FIG. A schematic diagram of the timing circuit shown in FIG. 6 is as follows.
It is also a schematic diagram of the control circuit. 20... Fluid sampler, 21... Compressed air assembly, 22... Battery pack, 25... Timing circuitry, 27... Control circuitry, 29, 31... Casing, 33... Battery, 35... ...Container, 37...
...Indentation, 55...Flowmeter, 61,63,65...
…boss, 79…groove, 83…filter assembly,
93... pump assembly, 95, 97... damper assembly, 99... regulator, 103, 105... casing, 106... suction groove, 107... fitting, 108... discharge groove, 120... Upper valve plate, 122... Lower valve plate, 155... Motor,
167...Diaphragm assembly, 169, 17
1,237...Diaphragm, 193,195...
... Valve plate, 211, 213 ... Valve seat, 215, 21
7... Valve plate, C1, C3... Capacitor, 1C3
... Capacitor, 1CR4 ... Light emitting diode,
CK...Clock input, 1CR1 to 1CR8...Diode, D0 to D3...Output, INH...Inhibition gate, LR...Input, OSC...Transmitter, MC...Motor controller, 014...Output, Q1...Transistor, 1R1, 1R2...Resistor, RP1...Resistor, R6...Comparison resistor, R11...Resistor,
R12-C4...Filter, R22...Resistor,
1S2...Switch, S1, S2...Selection switch, S3...Pressure switch, 1U1...Amplifier,
1U2...Adjuster, 1U3, 2U3, 4U3...
Latch, U1-3U1... operational amplifier, U2...
Frequency divider, 2U1, 3U1... operational amplifier,
U3...Counter, U4...Display, 4U1~Q
1...Amplifier unit, 7U1...Amplifier.

Claims (1)

Claims: 1. In a fluid sampler 20, grooves 83, 55, having means (83) for processing fluid;
106, 108 and a pump 9 for transporting fluid through the means (83) for treating said fluid.
3, a motor 155 connected to the pump 93 for driving the pump 93, a power supply means (23; +2.6V), and a motor 155 and the power supply for energizing the motor 155. and a motor circuit 27 interconnecting means (33; +2.6V), said motor circuit 27 comprising:
comprising continuously controllable transistor means (Q1) and a resistor R11 connected in series to the power supply means (23) to the motor 155; conducts a current whose magnitude is controlled to produce a voltage drop across the resistor R11, the magnitude of which is controlled by the motor 15 due to the current conducted by the motor 155.
5, the electrical load is controlled by the reaction between the fluid and the pump 93, and the fluid sampler 20
Means 1R1, R9, R3, coupled to the resistor R11 and the transistor means Q1 for controlling the current conducted by the motor 155 over the entire range of operation of the fluid sampler 20; 1R2,
Contains R22, R10, 4U1, and the motor 15
The control of the current conducted by the motor 155 does not rely on any pressure actuated monitoring, but merely depends continuously on the variation of the voltage drop across the resistor R11, and is controlled by the motor 155. The control of the current drawn is not digital but depends continuously on the variation of the voltage drop across the resistor R11, thereby ensuring that the current flow is controlled continuously over the entire range of operation of the fluid sampler 20. At any setting of the fluid sampler 20 (via resistor R3), the motor 155 is continuously controlled so that the motor 155
Fluctuations in fluid flow through the means for processing fluid 83 are continuously tracked so that the flow rate of fluid through the fluid sampler 20 is constant over the entire range of operation. A fluid sampler characterized in that the fluid sampler is adapted to be held in a fluid sampler. 2. The fluid sampler of claim 1, wherein the motor 155 is of the diaphragm type. 3. The control means (R11, 4U1) for controlling the motor 155 in a continuous manner in response to an electrical load on the motor 155,
5. A fluid sampler as claimed in claim 1, including feedback means R11, R10 without moving parts connected in series with the fluid sampler R11, R10. 4. The means (1R1, R9, R3, 1R2, R10, 4U1) for controlling the motor current are arranged via an operational amplifier 4U1 having a predetermined gain and the transistor means Q1 for controlling the motor 155. and an input 6 connected to the power supply means (33; +2.6V) and a feedback network (+2.6V, 1R1, R9,
R3, 1R2, R10, R11) and in the feedback network, the voltage generated by the current through the transistor means (Q11) across said resistor R11. A fluid sampler according to claim 1, wherein the drop is adapted to be fed back to control the conduction of said transistor means (Q11). 5 The power supply means (33; +2.6V) connects a voltage supply source and the operational amplifier 4 from the voltage supply source.
a voltage divider network (1R1, R9, R3) for providing a predetermined reference potential at input 6 of U1, said voltage divider network (1R1, R9, R3) 2. A fluid sampler as claimed in claim 1, including movable resistor means (R3) for varying the reference potential applied. 6 The feedback means (R11, R10)
motor current detection means (R11) connected between another terminal of the motor 155 different from the one terminal of the motor 155 and ground; and a motor current detection means (R11) connected between the other terminal of the motor 155 and the operational amplifier 4U
6. A fluid sampler as claimed in claim 5, including current feedback means (R10) for connection to said input 6 of one of the fluid samplers. 7. The fluid sampler of claim 6 including a current amplifier Q1 connecting said output 7 of said operational amplifier 4U1 to said one terminal of said motor 155. 8. The grooves 83, 106, 108 are connected to the suction groove 106 at the inlet 199, 219 to the pump 93 and the outlet 201, 221 of the pump 93.
and a pressure switch S3 communicating between the suction groove 106 and the discharge groove 108; The fluid sampling system of claim 1 is adapted to stop operation of the motor 155 in response to excessive vacuum pressure in the suction groove 106 or excessive vacuum pressure in the discharge groove 108. vessel. 9 a timing circuit 25 connected to said power supply means (33; +2.6V), said timing circuit configured to control a timing counter U3 and to preset a count in said timing counter U3; means S connected to
1, S2 and energizing the motor 155 in the motor circuit 27 to be activated and simultaneously energize the timing counter U3 in the timing circuit 25 to count. switch means 1S1 connected to and responsive to said timing counter U3 at the end of one count for resetting said timing counter U3 and for deenergizing said motor 155 and terminating operation of said pump 93; 2. A fluid sampler according to claim 1, further comprising means (TIM, 1U3, INH) connected to said timing circuit (25) and said motor circuit (27). 10 an amplifier 6U1 as electrical valve means, having an input terminal and an output terminal, an electronic latch 4U3, means (1Cr5) for connecting said input terminal to said motor circuit 27, and means (1Cr5) for connecting said input terminal to said motor circuit 27; means (R24) for connecting to electronic latch 4U3;
means (3U1, 303, INH) connected to said electronic latch 4U3, said motor circuit 27 and said timing circuit 25, said means (301, 303, INH) connected to said amplifier 6U1 and said electronic The power supply means (33; +
2.6V) below a usable magnitude, or via the motor 155 said power supply means (33; +2.6V);
for deenergizing said motor circuit 27 and said timing circuit 25 from said motor circuit 27 or said electric valve means (6U1) conducting sufficient current to satisfy the operating requirements of said pressure switch S3. 10. A fluid sampler as claimed in claim 9, wherein the fluid sampler is adapted to disable. 11 Means for disabling the above (5U1,
means (R12, 5U1) responsive to a current passing through said motor 155 to activate said means for disabling (5U1, 6U1, 4U3, INH, 303); 11. The fluid sampler of claim 10 comprising: 12 The power supply means (33; +2.6V) includes a battery, and the disabling means (5U1, 6U1, 4U3, INH, 301, 303) means (R18, R18,
11. A fluid sampler as claimed in claim 10, comprising: R19, R20, 6U1, 4U3, 301, 303, INH). 13. Current is supplied to the motor 155 from the power supply means (33; +2.6V) via the transistor means (Q ₁ ), and also from the disabling means (5U1, 6U1, 4U3, INH, 301,
303), the means for disabling (5U1, _6U1 , 4U3, INH, 301 , 303), the means ( _1CR5 , R18,
11. A fluid sampler according to claim 10, comprising: R19, R20, 6U1). 14 Current flows to the motor 155, the collector,
through said transistor means (Q1) having an emitter and a base, and also said disabling means (5U1, 6U1, 4U3,
INH, 301, 303) is responsive to an applied potential to conduct a current between the emitter and the base, and when the applied potential is reduced below some predetermined potential, The means for disabling the above (5U1, 6U1, 4U3, INH, 301,
303) means for activating (1CR5, 6U1)
11. The fluid sampler of claim 10 comprising: 15 The grooves 83, 106, 108 connect the suction groove 10 to the inlet 199, 219 to the pump 93.
6 and an outlet 2 to said pump 93
01,221 includes a discharge groove 108,
The fluid sampler 20 also includes a pressure switch S3 communicating with the suction groove 106 and the discharge groove 108;
3 is operable in an excess of vacuum in the suction groove 106 or in excess of pressure in the outlet groove 108, and furthermore, the means for disabling (R20, 7U1) means (R4, 7U1) responsive to the activation of said pressure switch S3 for activating the means (R20, 7U1) for
Claim 10 containing R23, R5)
Fluid sampler as described in Section. 16. In order for the circuit 27 to compensate for variations in resistance due to temperature of the winding material of the motor 155,
Means connected to the circuit 27 (R4, R23, R5)
2. A fluid sampler as claimed in claim 1, comprising: 17 In the fluid sampler 20, a groove 83,5 having means (83) for processing the fluid
5, 106, 108 and a pump 93 for transporting fluid through the means (83) for treating said fluid, the means (83) for treating said fluid comprising a fluid filter (means 83). ), the fluid filter progressively obstructs the flow of fluid through the groove as it filters fluid therethrough, and the fluid sampler 20 includes a A motor 155 connected to the pump 93 to drive the pump 93, a power supply means (33; +2.6V), and the motor 93
The motor circuit 27 includes a motor circuit 27 that interconnects the motor 155 and the power supply means (33; +2.6V) for energizing the motor circuit 2.
7 is a continuously controllable transistor means (Q1) connected to the power supply means (33; +2.6V) in series with the motor 155 and a resistor R.
11 and conducts a current through said motor 155 whose magnitude is controlled by said transistor means (Q1), said current flowing through said resistor R
11 , the magnitude of which is continuously dependent on the electrical load of the motor 155 due to the current conducted by the motor 155 , where the fluid filter increased to progressively impede the flow of fluid through the groove, and furthermore, the fluid sampler 20 allows the current conducted by the motor 155 to pass through the entire range of operation of the fluid sampler 20. means (1R1, R9, R3,
1R2, R22, R10, 4U1), and the control of the current conducted by the motor 155 simply follows the variation in voltage drop across the resistor R11 without being responsive to any monitoring of pressure actuation. and the control of the current conducted by the motor 155 is not digitally dependent, but is continuously dependent on the variation of the voltage drop across the resistor R11, thereby Continuously controls the motor 155 at any setting (by resistor R3) of the fluid sampler 20 throughout the range of operation of the fluid sampler 20, such that the motor 155 The changes in said flow of fluid through the means (83) for treating fluid are continuously tracked, in which case the flow of fluid through said grooves is relative to the flow generated by said filter. A fluid sampler characterized in that it remains substantially constant despite continuous disturbances.