DE359904C - Device for measuring and displaying the changes in such physical states that can be determined on a galvanometer - Google Patents

Description

Device for measuring and displaying the changes in such physical Conditions that can be determined on a galvanometer. Subject of the invention is a device for displaying, measuring and recording a state or the Change one such. The device can be used to measure chemical, physical, electrical or other states are used, but in particular it is used for measuring determined by temperatures and temperature changes.

The subject of the invention consists of a writing apparatus or a device connected to a writing device, which has one or more electrical circuits regulates, by means of which the size or the change in size of the condition to be measured, in particular a temperature is displayed. This can be used to add a signaling device, the z. B. of incandescent lamps o. The like. Can be connected by the general the instantaneous exceeding or falling below a certain normal state or a certain normal temperature is displayed.

In the embodiment shown, the measuring device is of several Temperature meters, e.g. B. thermocouples, resistance thermometers or the like., Influenced, which have very different temperatures and are also in very different places, z. B. can be located in different ovens and alternate with the display device be associated. The measuring device has the advantage that with her for Display of temperatures optionally a single measuring instrument, e.g. B. an d'Arsonval galvanometer, for all thermometers together or a special display instrument for each thermometer can be used.

In the drawing, Fig. I is a perspective view of the whole Device, Fig. Z a detail, Fig. 3 a section along line 3-3 of Fig.2, Fig. 4 is a circuit diagram for Fig. I with a display instrument and a signal device for several thermometers, Fig. 5 a corresponding circuit diagram with separate ones Display instruments and signaling devices for each thermometer, Fig. 6 one piece of writing paper with records of the writing device.

Part of the measuring device shown here is already included as a component a control device known, however, the invention is not to the use this part limited.

An electric motor M or some other drive device rotates a shaft i at as constant a speed as possible. This drives a worm wheel 3 seated on a shaft 4 by means of a worm 2. A lever s suspended swingably at its upper end carries an arm 6 swingable about a horizontal axis, both ends of which are covered with plates 7 made of cork or some other material with a high coefficient of friction are. These lie against the edge 8 of a rotatable disk g which is fixedly seated on a shaft io. On the shaft 4 there is an eccentric ix which, in certain time segments, presses the lever s against the pressure of a spring (not shown) and thereby lifts the plates 7 from the edge 8 of the disk g. As the eccentric ii continues to rotate, the spring presses the lever 5 back and thus the plates 7 back against the edge 8. On the shaft 4 there is a second eccentric i2 which comes into operation after the eccentric ii has lifted the plates 7 from the edge 8 and which then acts against a contact piece i3 at the lower end of an arm 14 which is attached to a pin 16 swingable bracket 15 is seated. An upright sheet 1.7 is attached to the bracket r5, the upper edge 18 of which rises from the center to both sides. Over the edge 18 the pointer plays ig a measuring instrument, for. B. a galvanometer with movable coil 2o. On both sides, the plate 17 has stops 21 which limit the deflection of the pointer. Immediately above the pointer ig are the horizontal edges 22 of angle levers 23, which are schwingbax around pin 24 and are so opposed to each other that they leave a gap between them, into which the pointer ig can enter in its zero position. Usually, the pointer ig swings freely between the edge 18 of the plate 17 and the lower edges of the angle lever 7.3. The downwardly pointing legs 25 of the latter are pulled against each other by a spring 26 and rest on pins 28 on a triangular plate 27 which is pivotably mounted at the lower end of the lever 5 and connected to the transverse arm 6. This has stops 29 at both ends, against which two eccentrics 30 seated on the shaft 4 act, bringing it back into its horizontal position.

On the shaft io there is a disk 31 made of insulating material, around the edge, if necessary, a helically wound resistance wire R is placed. A fixed contact 32 slides on it, which we will speak of later will be. The disk 31 can by means of a clamping screw passing through its hub 34 33 in the correct angular position to other disks sitting on the shaft can be found on the latter.

On the shaft io there is still a disk 35, on whose Circumference resistors 36, 37, which are part of a Wheatstone bridge circuit form, lie. To set the disc 35 in its angular position to the rest Disks on the shaft io are used by a clamping screw 38 passing through their hub 39.

A third one, with a clamping screw 40 on its hub 41 on the shaft io lockable disc 42 carries arcuate contact pieces 43, 44 and 45, the are isolated from each other and from the rest of the device and for switching the signal devices to serve.

Finally, the shaft io carries two adjustable disks 35a and 42a, which carry resistors 36a and 37a corresponding to a second Wheatstone bridge circuit and a second set of contacts 43a, 44.9 and 45 "for switching on signaling devices.

The five disks can be separated from one another in the manner indicated Be appropriate, however, two or more of them can be made into a unit are united, on which the various contact pieces and resistors in their certain angular position are attached. So the two discs 35 and 42, and on the other hand the two disks 35a and 42a, each combined into one disk be, with both discs adjustable relative to one another with respect to their angular position are; however, the disc 31 is adjustable by itself.

In FIGS. 2 and 3, such a disk 356 produced by the union of the disks 35 and 42 is shown, for example. The union of the disks 35a and 42a has the same shape. In the embodiment of Figs. 2 and 3, it is assumed that the disk 35 6 sits at the end of the shaft io, but it can instead be attached at any other point on the shaft. In the representation of the exemplary embodiment, the angular position is set in that the hub 39a of the disk is pressed with friction against a collar 396 of the shaft by means of a nut 35 '. The resistor 36, 37 can be seen on the circumference of the disc, which can have the form of a wire wound onto a core 35d and insulated from it. The wire ends at a and b (Fig. 2), while the core 35d is longer and is clamped to the edge of the disk 35 by means of a clamping piece 35e and a screw Mf. On both sides of the disk 3511, plates 359 and 351e made of insulating material projecting towards the outside are screwed on, which lift off the sliding contact 59 when the disk is rotated 18o 'from the position shown in FIG. The mentioned contact pieces 43, 44, 45 are attached to one end face of the disk 356.

A disk of suitable diameter, provided with a groove on the circumference and around which a cord 47 is placed, is also seated on the shaft 1o. This leads over rollers 48 to a pen 49 running in the horizontal direction on a guide (not shown). Below this, the writing paper P unwinds from a roller 50 , with it going over a roller 52 which is at the edge with teeth in rows of holes 51 of the Paper engages. The roller 52 sits on a shaft 53 which is driven by the motor M via a worm 54, a worm wheel 55, a shaft 56, a worm 57 and a worm wheel 58.

As can be seen from Fig. 4, the resistor R forms the measuring wire in a circuit for comparing voltages. This contains several resistors in two branches 6o and 61, which are parallel to each other and with a battery 62 and a control resistor 63 are connected in series. Serves in a known manner a normal element S to it, with the help of the regulating resistor 63 in the branch 6o to produce a certain amperage. For this purpose, a contact 64 is pressed down and thus the normal element S with the galvanometer G one behind the other and both closed connected in parallel to the resistor 65 of the branch 6o. The pointer of this galvanometer is the pointer i9 in Fig. i. .

In the normal operation, the normal element S is switched off and a switch 66 closed by which a terminal of the galvanometer G with a Line 67 is connected. This ends in two contact fingers 68 and 68a, which on grind a shift drum C. The latter sits on the shaft. 56 and is from her offset in rotation (Fig. i). The contact finger is in the position shown in Fig. 4 68 Via a contact piece of the shift drum with a contact finger 69 connected, one line of which leads to one terminal of a thermocouple T. The other terminal of the same is via a line 7o with the one on the resistor R sliding contact 32. The clamping of a second thermocouple T are on the one hand with the line 7o and on the other hand with a dragging on the shift drum C. Contact finger 71 connected. With further rotation of the shift drum one connects their contact fingers 71 and 68a with one another. The arrangement of the Shift drum is such that it alternates between the thermocouples T and T1 Lines 67 and 7o sets. The arc-shaped contact strips of the shift drum, which the different thermocouples are assigned, have different lengths, so that the time periods during which the thermocouples with the lines 67 and 71 have a different duration for each of the elements. Through this it is achieved that the pen 49 (Fig. 6) for the one thermocouple is longer Dashes, e.g. B. 49a, and for the other shorter strokes, 496 makes. These strokes stand in the longitudinal direction of the paper P traveling in the direction of the arrow. The association of the recorded curves with one or the other thermocouple is made up of the different lengths of the lines that make up them, recognizable.

In the embodiment described here, there are only two thermocouples T and T, but the number is not limited to this. It can also a larger number of thermocouples can be attached, with the number the Wheatstone bridges, indicators and signal lamps accordingly is to be increased.

In the circuit diagram, the thermocouples are close together drawn. In reality, however, they can be at any distance from each other be housed and have widely differing temperatures, e.g. B. in whole different oven.

If the thermal element T is in the position of the shift drum C on the lines. 67 and 7o, the resistors 36, 37 are on the disk 35 and the resistors 74, 75 connected to them with the measuring instrument V in connection. The resistors 36, 37 are shown as one and the same resistance wire, on which a contact 59 slips. When rotating the disc 35 in different positions is always the piece of resistance wire lying on the right side of sliding contact 59 the resistor 37 and the remaining part on the left-hand side, the resistor 36. The two resistors 36, 37 form together with the two fixed resistors 74, 75 the four sides of a Wheatstone bridge circuit in which the two Pages 36, 37 can be changed by rotating the shaft io. At the union point the resistors 74, 75 is a line 76 and to the sliding contact 59 is a line 77 connected to a suitable power source, e.g. B. to an electrical Light guide of constant voltage. Between resistors 36 and 74 a line 72 is branched off, which leads to the one terminal of a correspondingly divided Measuring instrument V, e.g. B. an d'Arsonval galvanometer, goes. Of this only is the rotatable coil is drawn, the permanent magnets are omitted from the drawing. The pointer 83 sits on the rotatable spool and plays over two scales s' and si. However, it is sufficient if only one of these is available. The scale s is with one appropriate classification, e.g. B. in voltage, current or temperature units divided. In the exemplary embodiment, it is divided into temperature degrees because it should display the temperature of the thermocouples. The scale s can be around the wave of the Coil 82 can be arranged rotatably The scale s, can be described as a deviation scale, since it is supposed to indicate by how much the current temperature is from a certain one Normal temperature, which corresponds to its zero point, deviates. The lateral rashes indicate the deviation on it, for example in temperature units, without the Display the height of the temperature itself. One connected in series with the measuring instrument V. Resistor 78 is used to compensate for the resistance of lines 72, 79 and 82 or other possible variables. From the resistor 78 one leads Line 79 to contact fingers 8o and Boa, which work together with contact fingers 81 and 8112. A line 82 leads from the contact finger 81 to the connection point of the resistors 37 and 75 of the Wheatstone Bridge. The contact fingers 8o and 8i are through a Contact piece of the shift drum connected to each other as long as the thermocouple T is on, and connect the measuring instrument V to the aforementioned one in this way Wheatstone Bridge.

In the same way, while the thermocouple T1 is connected to the lines 67 and 7o, contact fingers 8o11 and 8i12 connect the measuring instrument V to the corresponding points of a second Wheatstone bridge which is formed by the resistors 36a, 37a, 74a and 75a. The resistors 36a and 37a are rotatable with the disk 35; A contact 5g12, which is connected to line 77, slides on them. A connection to line 76 branches off between resistors 7421 and 7511. The junction of the resistors 37 ″ and 75a is connected by a line 82a to the contact finger 81a, through which the measuring instrument V is switched into this circuit.

Four electrical signal lamps g, b, w and y, which can be colored green, blue, white and red accordingly, are connected with one pole to one conductor 83 of a direct current line, t. This can be the same line from which the conductors 76, 77 are fed. The associated other conductor 84 is connected to two contact fingers 85 and 85a, with which contact fingers 86 and 86a work together. In the position of the switching drum C according to Fig. 4, in which the thermocouple T is switched on, the bei.den contact fingers 8511 and 86a are connected to one another by a sliding piece, whereby a line 87 is connected to the conductor 84, which leads to two sliding contacts 89 and go leads. These slide on the contact pieces 43, 44, 45, which rotate together with the resistors 36, 37 of the Wheatstone bridge. In a different position of the switching drum, in which the thermocouple T1 is switched on, the contact fingers 85, 86 are connected to one another, whereby a line 88 is connected to the conductor 84. This leads, on the one hand, to lamp g and, on the other hand, to two sliding contacts 8g11 and goa, which slide on contact pieces 43a, 44, 45a. The latter lie on the disc on which the changeable ones. Resistors 36a and 3711 of the second Wheatstone bridge are attached and which also rotates with the shaft io. In the position of the parts according to Fig. 4, the circuit of lamp g is open. In the presence of two thermocouples, the lamp g, by not burning, indicates that a certain thermocouple, in the present case the element T1, is switched off, and consequently the thermocouple T is switched on. When the thermocouple T i is switched on later, the contact fingers 85 and 86 are connected to one another, as a result of which the lamp g lights up and indicates that this element has been switched on.

The contact pieces 43, 44, 45 are correspondingly connected to the contact pieces 43a, 44a, 45a and also to the free poles of the lamps y, w and b.

In Fig. 5 the arrangement is essentially the same as in Fig. 4, but each thermocouple has a special display instrument and a special signaling device. The reference numbers are with the corresponding Share the same as in Fig.4.

Here, too, the thermocouples T, T1 or the device corresponding to them are alternately switched to the lines 67, 70 by a switching drum C driven by the shaft 56. If the thermocouple T is switched on in the illustrated position of the shift drum C , a circuit is closed at the same time via the contact fingers 8o, 81 and the lines 79, 72 and 82, which is connected by. the upper Wheatstone bridge with the variable resistors 36,37 and the fixed resistors 74, 75 leading to the measuring instrument V. Furthermore, in this position of the switching drum, in which the thermocouple T is switched on, the group y, w, b of the signal lamps is in the working position, namely that the contact fingers 85a and 86a are connected to one another, of which then, as in Fig 4, the line 87 leads to the sliding contacts 89, go, which slide on the contact pieces 43, 44, 45 that are rotatable together with the resistors 36, 37 of the Wheatstone bridge. At a later time, when the thermocouple T 1 is switched on, a second group of signal lamps y1, wi, b1 comes into the working position, since the contact fingers 85, 86 are then connected to one another. From the latter, a line 88 leads to sliding contacts 8g11, goa, which slide on contact pieces 4311, 44a, 45a. These rotate together with the variable resistors 3611, 37a of a second Wheatstone bridge circuit, to which fixed resistors 74a and 75a belong. If the thermocouple TI is switched on, the points at which the resistors 36a and 74a or 37a and 75a are connected are connected to the second measuring instrument V1 by lines 7211 and 8211 via the contact fingers 8o11 and 8z11 and a control resistor 78a.

The method of operation of the device is as follows: If the thermocouple T is switched on, its electromotive force acts in opposition to the voltage of the battery 62 on the galvanometer G. If the two voltages just cancel each other, the galvanometer remains at rest and its pointer is shown in Fig. i drawn center position. Now increases. the temperature of the thermocouple T, its electromotive force increases and causes the pointer ig to deflect, for example to the right, whereby it is clamped between the inclined edge 18 and the lower edge 22 of the right-hand angle lever 23 as a result of the perodic lifting of the bracket 15 by the eccentric iz and a swing of the arm 25 in the clockwise direction about its pivot point 24 is caused. Here, the arm pushes the right-hand pin 28 of the plate 27 in front of it and thereby pivots the transverse arm 6 in the clockwise direction. This happens while the plates 7 are lifted off the edge 8 of the disk g by the eccentric ii. The angle by which the arm 6 deflects depends on the angle by which the pointer ig deflects. If the eccentric ii exposes the lever 5, the plates 7 again lie against the edge 8 of the disk g. The left-hand eccentric 30 then strikes the left stop 29 and rotates the transverse arm 6 and with it. the disk g back against the clock by the same angle. As a result, the resistance R is shifted against the sliding contact 32 in the sense that it seeks to establish a balance of the electromotive forces. As a result, the deflection of the pointer ig decreases and when equilibrium is established, possibly after repeating the process, it returns to its rest position shown in Fig. I, whereupon there is no further influence on the wave io. The system is then in equilibrium for the instantaneous temperature of the thermocouple T. While this state is reached, the pen 49 shifts sideways on the paper and now makes a long stroke 4g11.

If the temperature of the thermocouple T is above normal when this state of equilibrium is reached, the contact piece 43 has now come under the sliding contact 89 and has closed the circuit of the red lamp r. So this indicates that the temperature is too high. If this temperature is close to the normal temperature, then the contact piece 43 lies under the sliding contact 89, while the contact piece 44 is still under the sliding contact go. In this case, both lamps r and w light up, indicating that the temperature is too high, but only by a small amount. Similarly, if the temperature of the thermocouple T, at which the pointer ig is in the rest position, is too low, the contact piece 45 comes into contact with the sliding contact go and causes the blue lamp b to light up. This shows that the temperature is too low. If the temperature is only slightly too low, the contact pieces 45 and 44 touch the sliding contacts go and 89 at the same time, so that the lamps w and b light up at the same time.

While in the manner assumed above the thermocouple T is switched on for the duration of a partial rotation of the switching drum C and while the device brings itself back into equilibrium or moves in a direction in which it restores the state of equilibrium, the resistors 36,37 of Wheatstone bridge rotated by the same angle and in the same direction as the resistor R. If, for example, the temperature of the thermocouple T is higher than normal, the resistors 36, 37 move from the position shown in Fig. 4 in the direction opposite to the clockwise twisted and the resistance wire 36 becomes shorter than the resistance wire 37. The Wheatstone bridge circuit is thereby out of balance, and a corresponding potential difference now acts on the conductors 72, 82 in a certain direction. As a result, the measuring instrument V, which is classified according to temperature degrees, is deflected, for example to the right. Its pointer 83 then shows on the scale s1 in temperature degrees the amount by which the temperature of the thermocouple T deviates from the normal temperature. The latter corresponds to the zero point on the scale s1.

Assume that the normal temperature for the thermocouple T is i2oo °, the scale s is rotated so that when there is no current in the galvanometer coil 82 the pointer 83 points to izoo ° (Fig.4). The graduation i2oo of the scale s falls that is, together with the zero line on the scale s1. As assumed, the pointer strikes 83 to the right, at the same time it shows the real temperature on the scale s of the thermocouple T and on the scale s1 the deviation from normal temperature at. In some cases it will not be necessary to attach both scales; according to the invention there may be a scale or both.

If the temperature of the thermocouple T falls below normal temperature, sc the pointer 83 deflects to the left, since the polarity is at the connection points of the resistors 74,75 with the lines 72, 8z reverses.

What was said here about thermocouple T also applies to thermocouple T1. Both elements are alternately applied to the circuit containing the resistor R and the galvanometer G for comparing the voltages by the switching drum C, which is rotating at an appropriate speed. At the moment when the thermocouple T1 is switched on, the line 84 is disconnected from the line 87 and connected to the line 88, whereby the sliding contacts 8911, goa are switched on, the contactors 43a, 37a rotating with the bridge resistors 36a, 37a. 44a, 45a grind so that the lamps r, w, b (Fig. 4) now come into their working position via these. The function of the signal lamps is the same as that described for thermocouple T. Furthermore, when the thermocouple T1 is switched on, the connection between the measuring instrument V and the first Wheatstone bridge 36, 37, 74 75 is interrupted and a connection to the second Wheatstone bridge is established via the line 8211. The measuring instrument V then shows, as before, the instantaneous temperature of the thermocouple T1 on the scale s and the deviation from normal temperature on the scale s1.

The activation of the thermocouple T1 is achieved by the burning of the green signal lamp, the activation of the thermocouple element T is on the other hand can be recognized by the fact that the green lamp is not on.

In the circuit according to Fig. 5, the mode of operation is the same as in the circuit according to Fig. 4 with the following exceptions Here is for each of the Wheatstone Bridges a special measuring instrument V or V1 available through the shift drum C is switched on alternately, according to the activation of the thermocouples T and Tl and both the real temperature as well as the deviation from the normal temperature.

Also there are two groups of red, white and blue signal lamps present, each of which is permanently connected to one of the Wheatstone bridges and which alternately, depending on whether the thermocouple T or TI is switched on, in working position. come. As in the case of Fig. 4, shows the lighting up the white lamp indicates that the temperature is normal, the lighting of the red lamp, that it is too high and the flashing of the blue lamp that it is too low. Even shows the simultaneous burning of the white lamp with the red or blue lamp indicates that the temperature is just a little too high or too low.

The interruption of the circuits of the measuring instruments V and V, by the switching drum C can be omitted and these can remain permanently connected to their Wheatstone bridges. However, in this case, if z. B. the thermocouple TI is switched off, the measuring instrument V1 a temperature, since its Wheatstone bridge is moved out of its zero position by the deflection made by the pointer 19 under the influence of the thermocouple T by the device according to Fig. This display is but disregarded as long as none of the RL signal lamps, w1 or lights b1 and thus the elimination of the thermocouple Tl visible - is. PATENT CLAIMS:

Claims (6)

i. Device for measuring and displaying changes in such physical states that can be determined on a galvanometer, thereby characterized in that a galvanometer changing its deflection (i9, 2o) by immediate Influence of a mechanically acting device (i to 18, 21 to 30) resistances (36, 37) changed accordingly in a Wheatstone bridge, whereby the The deflection of an indicating instrument (V) connected to it in the same way changes. 2. Measuring device according to claim i, characterized by a thermocouple (T) which is switched into a circuit that includes a galvanometer (G) and a variable resistance (R), whose under the influence of the galvanometer the adjustment that takes place acts on the Wheatstone bridge (36, 37, 74, 75), that the changes in state to be measured are displayed by the measuring instrument (V). 3. Measuring device according to Claimi and 2, characterized by a plurality of thermocouples (T, T1) and several Wheatstone bridges associated with them, be; who take turns one and the other thermocouple from a switching drum (C) with the galvanometer (i9, 2o) and the circuit containing the variable resistor (R) while at the same time the shift drum (C) turns on the Wheatstone ash Bridge with a measuring instrument specially designed for you or with a common measuring instrument (V) connects. 4. 14leßvorrichtung according to claim 2, characterized in that under the influence of the galvanometer (G) contacts (43, 44, 45) are controlled by circuits, the signal devices (b, y, w) to display a change in the physical to be measured Condition included. 5. Measuring device according to claim i, 2 and 4, characterized in that one or more of the display devices (b, y, w) indicate that the condition to be measured is higher than normal, and others indicate that it is lower than normal. 6. Embodiment of the measuring device according to claims 1 and 2, characterized in that the galvanometer (G) is a device affects, which acts on a pen (49) that the changes to the measured physical state.