Electronic roller tape measure

Abstract

The invention relates to a roller tape measure (1) comprising a housing (20) and an extendable tape measure (30), wherein the extendable tape measure (30) is connected to a tension ring (40) at the start (37) of the tape measure (30). According to the invention, the housing (20) has at least two receiving devices (21, 23) for the tension ring (40), in which the tension ring (40) can be received, wherein a magnetically sensitive element (22, 24) is present in each of the at least two receiving devices (21, 23), which magnetically sensitive element can be triggered by a magnet (41) in the tension ring (40), wherein each magnetically sensitive element (22, 24) is connected to an electronic reading device (50), which activates a different operating mode via the triggered state of the particular magnetically sensitive element (22, 24).

Description

[0001] Electronic tape measure

[0002] The invention relates to a tape measure comprising a housing and an extendable tape measure, wherein the extendable tape measure is connected to a pull ring at the beginning of the tape measure.

[0003] To measure the dimensions of an industrially manufactured product, for example, in quality control, it is necessary to measure each product individually, either automatically or manually. For quality control or sample testing, each individual product is subjected to precise, non-destructive measurement, and the behavior of the measured value across a large number of measured products can be used to draw conclusions about the factors influencing production. In the textile industry, where a large proportion of manual production predominates, it is very important to verify the precise dimensions of the manufactured textiles, because the actual dimensions of a mass-produced garment can vary due to a multitude of unstable manufacturing factors.There is also a need for a measuring tool that can be used quickly, easily and reliably to statistically record the radius of a large number of objects, be it the average radius and length of a person's extremities, the average radius of the body and the instep measurement of animals in breeding or fattening, or even the radius and length of harvested branches in forestry.

[0004] The object of the invention is to propose a tape measure for use in quality control and / or sample control, with the aid of which a large number of measurements can be carried out reliably and easily for the user. The object of the invention is achieved in that the housing has at least two receiving devices for the pull ring, in which the pull ring can be received, wherein in each of the at least two receiving devices there is a magnetically sensitive element which can be triggered by a magnet in the pull ring, wherein each magnetically sensitive element is connected to an electronic reading device which activates a different operating mode based on the trigger state of the respective magnetically sensitive element. Further advantageous embodiments are specified in the subclaims to claim 1.

[0005] According to the concept of the invention, the roller measuring tape has, in or on its housing for the rolled-up measuring tape, various receiving devices for a pull ring at the beginning of the measuring tape. These receiving devices can be indentations or recesses in the housing into which the pull ring can be inserted and, if necessary, locked in place by a locking device. The locking can be implemented by a clamp fit, a magnetic holder, or a closure. Located in the locking device is a magnetically sensitive element, such as a reed relay as a switch or a magnetic sensor, such as a Hall sensor or a magnetic head, which changes its inductance due to a magnetic flux.An electronic reading device, an integrated part of the tape measure, uses the aforementioned sensors or switches to detect which holding fixture the pull ring is in and activates a different operating mode depending on the position of the pull ring in one or another holding fixture. Different operating modes can be: a length measurement as a first operating mode and a diameter or radius measurement in a second operating mode. It is also possible for both operating modes to record a length, whereby the operating modes differ in that a different extension state of the tape measure is taken into account when positioning the pull ring in the various holding fixtures during the length measurement.This can be advantageous if a pull ring can be locked in the housing to measure the circumference of an object, with part of the housing of the tape measure resting against the object to be measured. In a preferred embodiment of the tape measure presented here, a first operating mode is "length measurement," in which the electronic reading device detects a length based on a measuring standard encoded on the tape measure, and a second operating mode is "circular measurement," in which the electronic reading device detects a diameter based on a measuring standard encoded on the tape measure, where the diameter is defined as the detected length divided by the number pi.

[0006] For industrial use in quality control and for capturing as many measured values ​​as possible in a short time, it is advantageous if the tape measure housing contains an electronic reading device for electronically reading the scale. This device transmits the measurement result to a remote receiver via a radio protocol using a request signal in the form of a button press on an electrical switch. For this purpose, the electronic reading device is connected to a device for wireless near-field communication, such as a Bluetooth® module or a WLAN module, via which the electronic reading device outputs the detected measurement as a digitally coded value. The detected value can be transmitted as a digitally coded number.In a special embodiment of the tape measure, the device for wireless near-field communication can be provided to mimic a wireless keyboard and to transmit the measured value as a keystroke of a number including a terminating character, such as a carriage return or a tab character. These special characters are used in computer programs to terminate the input in one data entry field and activate a new field for data entry. In this way, a large number of measured values ​​can be recorded using a program designed for manual data entry.

[0007] It is possible to activate n+1 operating modes with n recording devices by activating a standard operating mode when no switch or detector / sensor in the recording devices is activated and activating the "sleep" operating mode when a predetermined switch or detector / sensor is activated.In a special embodiment with exactly two receiving devices, it is provided that the electronic reading device has the following operating modes: a) switched off, b) switched on in a first operating mode, c) switched on in a second operating mode, wherein the electronic reading device activates the mode a) "switched off" when the pull ring in a first receiving device activates the corresponding magnetically sensitive element by means of the magnet, b) "switched on in a first operating mode" is activated when the pull ring is not received in any receiving device and therefore does not activate a magnetically sensitive element with its magnet, c) "switched on in a second operating mode" is activated when the pull ring in a second receiving device activates the corresponding magnetically sensitive element by means of the magnet.This allows a distinction to be made between the operating states of length measurement, circular measurement, or diameter / radius measurement, and "off." The "off" state is triggered by the pull ring being placed in a storage position. In this case, a first operating mode is "length measurement," in which the electronic reading device detects a length based on a measuring standard encoded on the measuring tape, and a second operating mode is "circular measurement," in which the electronic reading device detects a diameter based on a measuring standard encoded on the measuring tape, where the diameter is defined as the detected length divided by the number pi. Various other configurable operating modes can be provided in the design of the tape measure.It is possible for the electronic reading device to output the detected measurement in a unit of measurement dependent on the configuration, such as metric (i.e. in mm, cm or m) or imperial (i.e. inch, ft and yard), through an electronic configuration.

[0008] Depending on the application, it may be advantageous if the tape measure can be locked in the extended position. In this case, a winding device for the extendable tape measure in the housing of the tape measure is provided with a friction wheel that can be mechanically activated by an adjusting knob. This friction wheel compensates for the restoring force of the winding device and fixes the extended state of the extendable tape measure. It is possible for the adhesive force of the magnet in the pull ring to be dimensioned such that it is higher than the restoring force of the winding device for the extendable tape measure. This has the advantage that the tape measure can be attached to a metallic surface, making it possible to measure a greater distance that cannot be measured with the arm span of a single user.

[0009] The measuring scale on the measuring tape can take different forms. It is possible for the measuring scale to be woven into the measuring tape as metallic threads. It is also possible to incorporate a magnetically coded band into the measuring tape, from which a measuring head reads the tape's extension. Finally, the measuring scale can be printed on the measuring tape. The measuring scale can be printed with an invisible ink that only becomes visible when illuminated with UV light. This allows a human-readable scale to be printed on the measuring tape, along with the electronically readable measuring scale.In a simple case, it is also possible to print a human-readable scale on one side and a measurement symbol on another side of the measuring tape; the sides can be the left or right side of the same surface of the measuring tape or the front and back of the same measuring tape.

[0010] In a roller tape measure, the tape measure can have an optical coding for electronic readout, whereby the optical coding has an absolute dimension, i.e. the coding at each point on the tape measure is structured in such a way that the absolute dimension of the tape measure can be read from it at that respective point. The coding can, for example, be selected from the group consisting of: optical time signatures, measuring embodiments using the vernier method using two measuring embodiments arranged next to one another at different frequencies, barcodes and incremental codes which can be used to determine the correct dimension by counting as the tape is extended. Other optical machine-readable codes with an absolute dimension coding are also possible. This means that the measuring embodiment cannot be structured as an absolute dimension.In this case, a detector counts the passage of optical markers and counts the forward or backward passage of the optical markers, thus calculating the current measurement position. The absolute code makes it easy for the user to calibrate the tape measure. To do this, the user only needs a reference meter, which they measure with the tape measure.

[0011] The calibration can be carried out by a qualified official in the same way.

[0012] For trouble-free use, the tape measure can be provided with a contactless charging device for the electronic reading device in the form of an inductively coupled current transmission.

[0013] The invention is explained in more detail with reference to the following figures. They show:

[0014] Fig. 1 shows a tape measure according to the invention with a rolled-up tape measure and pull ring in a first receiving device as a rest position,

[0015] Fig. 2 shows the tape measure from Figure 1 in a view of the second receiving device, Fig. 3 shows the tape measure from the previously mentioned figures in a first operating state "length measurement",

[0016] Fig. 4 the tape measure from the previously mentioned figures in a first operating state "round measure",

[0017] Fig. 5 the measuring tape of the tape measure with printed scale, measuring standard and with pull ring,

[0018] Fig. 6 is a schematic diagram showing the tape measure locking mechanism.

[0019] Figure 1 shows a tape measure 1 according to the invention with a rolled-up tape measure 30 and pull ring 40 in a first receiving device 21 as the rest position. The housing 20 is essentially shown in a view from the left side, if the position where the tape measure 30 is pulled out is considered the "front side." A display 52 is provided in the housing 20, on which the measurement read by an electronic reading device 50 (not shown here) is displayed. The display 52 also serves for configuration and to display the operating status. The operating status is automatically selected by the positioning of the pull ring 40. This position can be either in the receiving device 21 integrated in the housing or in the receiving device 23 integrated in the housing. In addition, positioning in neither of the receiving devices 21, 23 can trigger another standard operating state.The internal reading device 50 can be equipped with a device 51 for near-field communication in order to transmit measured data to a receiver, usually a computer. Near-field communication protocols that specify both the physical transmission type and the communication protocol used can include BlueTooth®, WLAN, as well as wireless communication protocols that are less widespread. When measuring, a user can record a measured value by pressing the trigger button 53 and transmit it to a receiver using the near-field communication device 51. A mechanical setting button 36 is provided with which an internal, mechanically activated friction wheel can be activated, which compensates for the restoring force of a winding device provided inside the housing 20. In order to attach the tape measure to a carrying rope (English:A D-ring 25 is provided on the back of the housing 20 of the tape measure 1 for attaching a safety lanyard or for connecting a safety line. Inside the housing 20, near the receiving devices 21 and 23, there are magnetically sensitive elements 22, 24 that detect the positioning of the pull ring 40 attached to the tape measure 30. Reed relays can be considered as magnetically sensitive elements. However, it is also possible to use sensors that are sensitive to magnetic fields, such as a Hall sensor or a remote coil that changes its inductance in the presence of magnetic flux. Loudspeaker holes 55 are arranged around the adjusting knob 36, through which electronic trigger tones emerge from the housing 20. Magnetically sensitive elements are therefore electrical switches that can be triggered by a magnet, or sensors that detect a magnetic field or a change in a magnetic field.

[0020] Figure 2 shows the tape measure from Figure 1 in a view of the second receiving device 23 on the underside of the housing 20. The receiving device is shaped to receive and secure the pull ring 40. This view shows how the beginning 37 of the tape measure 30 is connected to the pull ring 40. The adjusting knob 36 from Figure 1 is also present here on the opposite and right-hand side shown here, because the adjusting knob 36 can be pushed to one side or the other. To do this, the user presses the adjusting knob 36 from the left side of the housing 20 or from the right side of the housing 20.

[0021] Figure 3 shows the tape measure 1 from the previously mentioned figures in a first operating state, "length measurement." In this state, the pull ring 40 at the beginning 37 of the tape measure 30 is not received in one of the receiving devices 21 or 23 in the housing 20 of the tape measure 1. Instead, the pull ring 40 is used by a user to pull the tape measure 30 out of the housing 20 of the tape measure 1 and to tension it against the restoring force F of an internal winding device 33 in order to measure a length l. In this illustration, dashed circles are sketched around the front part of the pull ring 40, which are intended to represent the actually invisible magnetic field lines of the magnet 41 present in the pull ring 40. This magnet 41 has various functions. Firstly, the magnet 41 holds the pull ring 40 in the receiving device 21 or 23. Furthermore, the magnet 41 triggers a magnetically sensitive element 22, 24 in the receiving devices 21 and 23.Finally, the magnet can be used to fix the pull ring 40 to a metallic surface in order to extend the usable arm span of a user when measuring a length l.

[0022] Figure 4, however, shows the tape measure 1 from the previously mentioned figures in a first operating mode, "round measure." For this purpose, the pull ring 40 is inserted into the lower receiving device 23. The magnet 41 in the pull ring 40 triggers the magnetically sensitive element 24 near the receiving device 23. This magnetically sensitive element 24 signals an electronic reading device 50 inside the housing 20 to output an average diameter d of an object 80 to be measured or a radius instead of a length l by dividing a measured length l by the number pi or by 2*pi, depending on whether the diameter or the radius is desired as the result.

[0023] Figure 5 shows the beginning of the measuring tape 30 of the tape measure 1 with the printed scale 31 and the measuring scale 35. At the beginning 37 of the measuring tape 30, the measuring tape 30 is connected to the pull ring 40. In the front part of the pull ring 40, which faces away from the measuring tape 30, there is a small magnet 41, in this case a bar magnet. This magnet holds the pull ring firmly in the receiving devices 21 or 23 and omits the magnetically sensitive elements 22 and 24.

[0024] Finally, Figure 6 shows a schematic diagram of the internal winding device 33. This winds up the measuring tape 30 against the force of a spiral spring. A friction wheel 34 can be mechanically activated by the adjusting knob 36, which adjusts the friction wheel when inserted, thereby clamping the measuring tape 30. The measuring tape 30 passes through an electronic reading device 50, which reads the current position from the measuring scale 35 when the measuring tape 30 is extended or retracted.

[0025] LIST OF REFERENCE SYMBOLS

[0026] Tape measure 41 magnet

[0027] Housing 50 reading device

[0028] Receiving device 51 Device for wireless near-field communication magnetically sensitive element 52 Display

[0029] Recording device 53 Release button magnetically sensitive 54 Control button

[0030] Element 55 speaker holes

[0031] D-ring

[0032] Tape measure, extendable 80 object

[0033] scale

[0034] Reel d diameter

[0035] Friction wheel F restoring force

[0036] Measuring standard l length

[0037] Adjustment knob L Operating mode

[0038] Start of the measuring tape R Operating mode

[0039] Pull ring

Claims

Electronic tape measure PATENT CLAIMS 1. A roller measuring tape (1) comprising a housing (20) and an extendable measuring tape (30), the extendable measuring tape (30) being connected to a pull ring (40) at the beginning (37) of the measuring tape (30), characterized in that the housing (20) has at least two receiving devices (21, 23) for the pull ring (40), in which the pull ring (40) can be received, wherein in each of the at least two receiving devices (21, 23) there is a magnetically sensitive element (22, 24) which can be triggered by a magnet (41) in the pull ring (40), wherein each of the magnetically sensitive elements (22, 24) is connected to an electronic reading device (50) which activates a different operating mode via the triggering state of the respective magnetically sensitive element (22, 24). A tape measure according to claim 1, characterized in that the electronic reading device (50) has the following operating modes: a) switched off, b) switched on in a first operating mode (L), c) switched on in a second operating mode (R), wherein the electronic reading device (50) activates the mode a) "switched off" when the pull ring (40) in a first receiving device (21) activates the corresponding magnetically sensitive element (22) by means of the magnet (41), b) "switched on in a first operating mode (L)" is activated when the pull ring (40) is not received in any receiving device (21) and therefore does not activate any magnetically sensitive element (22, 24) with its magnet (41), c) "switched on in a second operating mode (L)" is activated when the pull ring (40) in a second receiving device (23) activates the corresponding magnetically sensitive element (24) by means of the magnet (41).

3. A tape measure according to claim 2, characterized in that a first operating mode is "length measurement", in which the electronic reading device (50) detects a length (£) as a function of a measuring embodiment (35) encoded on the tape measure (30), and that a second operating mode is "circular measurement", in which the electronic reading device (50) detects a diameter (d) as a function of a measuring embodiment (35) encoded on the tape measure (30), the diameter being defined as the detected length divided by the circular number Pi.

4. Tape measure according to claim 2 or 3, characterized in that a first operating mode and a second operating mode differ in that the electronic reading device (50) takes into account a different extension state of the extendable tape measure (30) due to the different position of the at least two receiving devices (21, 23).

5. Tape measure according to claim 2 or 3, characterized in that the electronic reading device (50) is connected to a device (51) for wireless near-field communication, such as a BlueTooth® module, via which the electronic reading device (50) outputs the detected measurement as a digitally coded value.

6. Tape measure according to one of claims 1 to 5, characterized in that the electronic reading device (50) outputs the detected measurement with a unit of measurement dependent on the configuration, such as metric (cm) or imperial (inch), by means of an electronic configuration.

7. A tape measure according to any one of claims 1 to 6, characterized in that a winding device (33) for the extendable tape measure (30) has a friction wheel (34) which can be mechanically activated by an adjusting knob (36), which compensates for the restoring force (F) of the winding device (33) and fixes the extended state of the extendable tape measure (30).

8. Tape measure according to one of claims 3 to 7, dependent on claim 3, characterized in that the measuring embodiment (35) is present as a coded imprint on the tape measure (30).

9. Tape measure according to one of claims 1 to 8, dependent on claim 7, characterized in that the adhesive force of the magnet (41) in the pull ring (40) is dimensioned such that it is higher than the restoring force (F) of the winding device (33) for the extendable tape measure (30).

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