Medical devices with power-up routines

Abstract

The present invention relates to a method for powering up a medical device (1) powered by a battery (2). The method comprises performing an initial battery test. In the initial battery test, a voltage difference between the battery voltage measured without a test load and with a test load is determined. The test load is of an appropriate size and does not cause significant stress to the battery. The voltage difference is compared with a voltage difference threshold, which is predefined based on the voltage without the test load. The method further comprises: providing an alarm if the voltage difference is higher than the voltage difference threshold. The present invention further relates to a medical device implementing the method as described above, and a method for determining the relationship between the voltage difference and the voltage difference threshold. The present invention can be used to ensure that an alarm is provided if a newly inserted battery is too weak to power the medical device to fully power it up.

Description

Technical Field

[0001] The present invention relates to a battery-powered medical device, such as an extracorporeal insulin pump, and a method for powering up such a battery-powered medical device. The method particularly relates to testing the battery during power-up. Background Art

[0002] Battery powered medical devices are used in large and growing numbers in a variety of diagnostic or therapeutic applications. The field addressed hereinafter for exemplary purposes is that of an extracorporeal insulin pump which is carried substantially continuously by a person with diabetes (PwD) in the context of continuous subcutaneous insulin infusion (CSII).

[0003] Such external insulin pumps and various other medical devices are powered by a universal battery that is detachably arranged in a corresponding battery compartment of the medical device. When the battery is exhausted, the battery is usually replaced directly by the user.

[0004] Battery-powered medical devices are often designed to monitor the battery and provide an alarm or warning to the user when the battery is about to be depleted and needs to be replaced. In addition, battery-powered medical devices often perform a battery test as part of the power-up routine after the battery is replaced. This ensures that the newly inserted battery is indeed capable of powering the medical device. In order to test the batteries of medical devices, many methods have been developed, which generally rely on the measurement of voltage and internal resistance. Summary of the invention

[0005] However, performing a battery test according to the prior art generally subjects the battery to significant stress, which may result in an unexpected power failure. This may occur in particular if a battery that is generally unsuitable is used, or if a weak or substantially dead battery is mistakenly used in place of a new battery. If such a power failure occurs when powering up a medical device, the medical device may completely cease to operate without providing any warning or alert to the user, which is understood to be a cause of concern and distress to the user. Furthermore, in this case, no information about the battery test is stored in the history memory or history file of the medical device, complicating the diagnosis of the cause of the power failure, which further becomes a critical issue from a regulatory point of view.

[0006] A general object of the present invention is to improve the prior art regarding battery testing of battery powered medical devices. Advantageously, the risk of unexpected power failures due to weak or dead batteries is avoided or at least reduced.

[0007] The overall object is achieved by the subject matter of the independent claims, specific results and / or exemplary embodiments are defined by the dependent claims as well as by the entire disclosure.

[0008] A method for powering up a battery-powered medical device, the method comprising performing an initial battery test. The initial battery test comprises the following steps:

[0009] a) Determine the battery’s no-test-load voltage U without connecting a test load to the battery 无测试负载 ;

[0010] b) If there is no test load voltage U 无测试负载 Below the predefined no-test-load voltage threshold U 阈值，无测试负载 , an alert is provided and the method is terminated;

[0011] c) If there is no test load voltage U 无测试负载 Above the no-test-load voltage threshold U 阈值，无测试负载 , perform the following steps:

[0012] c1) Determine the test load voltage U of the battery with the test load connected to the battery 测试负载 ;

[0013] c2) No test load voltage U 无测试负载 and test load voltage U 测试负载 The voltage difference ΔU between the 阈值 For comparison, the voltage difference threshold ΔU 阈值 is based on the voltage U without test load 无测试负载 predefined;

[0014] c3) If the voltage difference ΔU is higher than the voltage difference threshold ΔU 阈值 , an alert is provided;

[0015] The method further comprises if the voltage difference ΔU is below a voltage difference threshold ΔU 阈值 , then execute the subsequent steps of the method.

[0016] Battery-powered medical devices may include:

[0017] a battery compartment designed to removably accommodate a battery and a contact element for electrically contacting said battery;

[0018] - a test load selectively connectable to the battery;

[0019] - A control circuit configured to execute a method for powering a medical device once a battery has been inserted into a battery compartment.

[0020] The method for powering up a medical device may be a method according to any embodiment as described above and / or further below.

[0021] The battery is generally of any suitable type. In a typical embodiment, the battery is a commonly available standard battery, such as, for example, a AA or AAA battery of a rechargeable or non-rechargeable type. The battery can also be made of a plurality of individual cells connected in series. However, it should be noted that the present invention is not limited to a specific type of battery, but in principle any type of battery can be used, i.e., a non-rechargeable battery (disposable battery) or a rechargeable battery (secondary battery), depending on the specifications and requirements of the medical device. The battery compartment is generally designed to allow the user to replace the battery.

[0022] Since the battery is contacted via the contact elements of the battery compartment, the transition resistance between the contact elements and the battery terminals of the battery acts in series with the internal resistance of the battery. The combined resistance is referred to in this document as the effective internal resistance R i In some typical embodiments, at least one of the contact elements is implemented as a contact spring. In this document, taking into account the effective internal resistance R i The voltage drop across the battery is usually referred to as the terminal voltage that can be measured in an operating medical device.

[0023] Subsequent steps of the method for powering up a medical device may include, for example, a memory check, a communication controller check, an electrode check, a sensor check, an alarm check, a general check of the medical device circuit, an acoustic and / or tactile indicator device test (e.g., a speaker, buzzer, or vibrator), a display test, and general initialization steps generally known in the art, as well as further battery tests described in more detail below. Some of these subsequent steps may be associated with a large amount of power consumption and therefore put a lot of stress on the battery. According to the present invention, these subsequent steps are only performed if the initial battery test is successfully passed.

[0024] It should be understood that the medical device draws an unavoidable baseline current when performing any operation, especially when performing an initial battery test. Therefore, the true open circuit voltage U0 of the battery is not available and cannot be measured, because the baseline current will cause a voltage drop across the effective internal resistance in any case. The baseline current is drawn by the control circuit in operation. In the following, the baseline current during the initial battery test is generally assumed to be a constant value.

[0025] When the no test load voltage is determined and measured in step (a), the baseline current is the only current drawn from the battery. Therefore, the battery load is minimal and the no test load voltage is as close to the open circuit voltage as possible.

[0026] In step (b) of the method, an alarm is provided and the method terminates, i.e., if the no-test-load voltage is below a predetermined no-test-load voltage threshold, the subsequent steps are not performed. This step ensures that the subsequent steps of the initial battery test are performed only if the battery is at least able to provide the power required for these steps. Thus, very weak or nearly empty batteries are screened out in this step. The alarm can be provided on one or more indicator devices of the medical device, indicated on a display of the medical device and / or provided on a remote device (e.g., a remote control or a smart phone) like other alarms.

[0027] In step (c1), another voltage of the battery is determined and measured as a test load voltage, wherein the test load is connected to the battery. Connecting and disconnecting the test load is controlled by the control circuit of the medical device. For this measurement, in addition to the baseline current, an additional test load current is drawn from the battery, resulting in a larger voltage drop across the effective internal resistance.

[0028] The test load and test load current are chosen so that connecting the test load does not significantly stress the battery, so it can be considered a "weak" test load. The test load current only needs to be large enough to produce a safely measurable voltage difference between the no test load voltage and the test load voltage.

[0029] In step (c2), the no-test-load voltage U measured in step (b) is 无测试负载 The voltage difference ΔU between the test load voltage measured in step (c1) and the voltage difference threshold is compared. The voltage difference threshold is predefined based on the absence of the test load voltage. 阈值 With and without test load voltage U 无测试负载 The relationship between may be stored in a memory of the control circuit, for example, by a mathematical function or in the form of a lookup table.

[0030] According to the comparison result, if the voltage difference is higher than the voltage difference threshold, an alarm is provided in step (c3) as described above and the method is terminated. Otherwise, the power-up is continued and completed by executing the subsequent steps of the method. Therefore, the subsequent steps of the method are only executed if the battery is able to power the medical device in the subsequent steps of the respective method of the power-up routine without the risk of sudden failure.

[0031] It is particularly noted that the initial battery test does not rely on explicit impedance measurements and further does not require any laborious calculation steps. Only two voltage measurements and subsequent threshold comparisons are required. It can therefore be implemented in an efficient and straightforward manner. The determination of the voltage difference threshold value according to the no-test load voltage is explained in more detail further below.

[0032] In general, the initial battery test is a two-step test, the first step being defined by method steps (a), (b) and the second step being defined by method steps (c1), (c2), (c3).

[0033] In a certain embodiment, the voltage difference threshold is a linear function of the no-test-load voltage. This type of embodiment is particularly advantageous with respect to simple evaluation with little computational effort.

[0034] In one embodiment, the test load is a constant resistance test load. In a typical non-limiting example, for example, for some types of in vitro insulin pumps, the test load voltage U 无测试负载 The range may be, for example, 1.0 V to 1.6 V, and a baseline current I of ~500 μA is typically used. B .

[0035] In a certain embodiment, the initial battery test includes storing the results of the initial battery test in a history memory of the medical device. The initial battery test according to the present disclosure ensures that a weak or nearly empty battery provides enough power to store the results of the battery test before any complete failure. For the purpose of device diagnosis, it is very necessary to store the results of the battery test, and it can further become a routine requirement. In a specific embodiment, the results are not stored under any circumstances, and the results are only stored when the storage criteria indicating that the battery may be insufficient are met. At least whether the initial battery test as described above is passed can be stored. In a further embodiment, the results can be stored for the first step of the initial battery test defined by steps (a) and (b) and the second step of the initial battery test defined by steps (c1), (c2), (c3). In addition, numerical values ​​such as no test load voltage and test load voltage can be stored and / or binary test results (e.g., "pass" or "fail") can be stored.

[0036] In one embodiment, the method comprises, if it is determined in step (c2) that the voltage difference ΔU is below a voltage difference threshold ΔU 阈值 , further battery testing is performed. The further battery testing includes drawing a further test load current, thereby stressing the battery beyond limits expected to occur during normal operation of the medical device.

[0037] In a certain embodiment, the method may further include, before step a): 0) turning on the power of the medical device.

[0038] The power supply can be turned on, for example, by activating a switch, by establishing a connection between the battery and a conductor of the medical device, such as by closing the battery compartment or by inserting the battery into the battery compartment, by connecting the battery to a battery contact, etc. Preferably, the circuit of the battery and the processor of the medical device are turned off. Such switches are generally known to the skilled person and include buttons, transistors, inductive switches, relays, etc.

[0039] In contrast to the initial battery test, which is designed to subject the battery to significant stress, the further battery test is a dedicated stress test that stresses the newly inserted battery to the limits of normal operation. For example, for some types of in vitro insulin pumps, the further battery test may include drawing a battery current of ~1.0A for 4ms. The further battery test may be considered a failure, for example, if the voltage at the end of the test drops below a predetermined threshold (e.g., drops below 985mV).

[0040] In a certain embodiment, the battery-powered medical device includes one or more DC / DC boost converters, which power at least some functional units of the medical device. In a certain example, the test load of such an embodiment is electrically arranged between the battery contact point and the input side of the DC / DC boost converter. The functional units powered by the DC / DC boost converter generally include control circuits (especially microcontrollers or processors), one or more indicating devices or displays (as described above), actuators (such as motors in the case of infusion pumps), communication interfaces, etc. Typically, most functional components and circuits of the medical device are powered by the DC / DC boost converter. In order to operate the medical device, it must be ensured that at any point in time, the minimum input voltage required on the input side of one side of the DC / DC boost converter will not be lower than this value. This requirement also applies to the initial battery test. However, in some alternative embodiments, the test load is arranged on the output side of the DC / DC boost converter.

[0041] In a certain embodiment, the control circuit includes a processor or a computer and a computer-readable storage medium, the computer-readable storage medium including instructions, when the instructions are executed by the processor or the computer, the instructions cause the processor or the computer to control the execution of the method for powering up the medical device. In the embodiment with a DC / DC boost converter as described above, the processor or the computer is usually powered via the DC / DC boost converter.

[0042] In a certain embodiment, the medical device is an external insulin pump configured to be carried by a user for extended periods of time under clothing and / or attached to the body.

[0043] In a certain embodiment, the present disclosure may be adapted and used for various battery-powered devices, including any battery-powered medical device, including but not limited to drug infusion pumps (including insulin pumps), blood glucose sensors, continuous glucose sensors, cardiac defibrillators, cardiac monitoring devices, etc. However, external insulin pumps are particularly important because their failure can directly lead to serious medical complications, and they need to be able to operate continuously basically around the clock. In addition, they are typically powered by ordinary general-purpose batteries, such as, for example, rechargeable or non-rechargeable AA or AAA batteries, and it is known that due to errors and / or lack of awareness, batteries that are usually unsuitable and / or almost dead are occasionally used or reused. In such cases, power failures as previously described may occur during the power-up process.

[0044] As known in the art, insulin pumps are designed to administer small amounts of fluid in the microliter or sub-microliter range with high precision. Other insulin pumps are typically designed to administer medication substantially continuously according to a basal infusion profile that varies over time, and further administer larger amounts of medication as needed.

[0045] A voltage U 无测试负载 Use in the method described above to determine the voltage difference threshold value ΔU 阈值 The method comprises the following steps:

[0046] (1) Determine the effective internal resistance R through experiments i and the open circuit voltage U0 of the battery capable of powering the medical device;

[0047] (2) Based on the functional relationship determined in step (1), the minimum no-test-load voltage U of the battery that will power the medical device without connecting a test load to the battery 无测试负载，最小值 Determined as a function of the open circuit voltage U0;

[0048] (3) Based on the functional relationship determined in step (1), the minimum test load voltage U of the battery that will power up the medical device when the test load is connected to the battery 测试负载，最小值 Determined as a function of the open circuit voltage U0;

[0049] (4) Based on the minimum no-test load voltage U 无测试负载，最小值 , with the open circuit voltage U0 as the parameter, according to the minimum no-test load voltage U 无测试负载，最小值 With minimum test load voltage U 测试负载，最小值 The voltage difference threshold ΔU is calculated by the difference between 阈值 .

[0050] In one embodiment, the method includes setting the effective internal resistance R iThe functional relationship between the value of and the value of the open-circuit voltage U0 is determined to be an approximately linear functional relationship.

[0051] In one embodiment, the method includes setting the voltage difference threshold ΔU 阈值 Calculations are linear approximations.

[0052] It should be noted that the voltage difference threshold ΔU 阈值 The method does not need to be implemented in battery-powered medical devices. Only the minimum no-test load voltage U 无测试负载，最小值 Determine the voltage difference threshold ΔU 阈值 is stored in a medical device.

[0053] On the contrary, according to the no-test load voltage U 无测试负载 Determine the voltage difference threshold ΔU 阈值 The method is performed by the medical device supplier at his facility. Here, the open circuit voltage U0 and the effective internal resistance R can be determined and measured. i .

[0054] Further explanation and aspects regarding this aspect of the invention are provided in more detail below in the context of exemplary embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Hereinafter, exemplary embodiments are discussed in more detail with additional reference to the accompanying drawings.

[0056] Figure 1 An exemplary battery-powered medical device having a battery is schematically illustrated;

[0057] Figure 2 An exemplary operational flow for powering up a medical device is shown;

[0058] Figure 3 An exemplary graph of the voltage difference threshold as a function of no test load voltage is shown. DETAILED DESCRIPTION

[0059] Figure 1 A battery-powered medical device 1 is shown, which is exemplarily an insulin pump in a schematic functional view, and a battery 2. The battery 2 is detachably arranged in a battery compartment 11 of the medical device 1. In addition, the battery 2, for example a rechargeable or non-rechargeable AA battery or AAA battery, is modeled with an open circuit voltage U0 and an internal resistance R i1 The battery 2 is connected to other components of the medical device 1 via the battery contact point 11a. The battery contact point 11a has an internal resistance R i1 The series transition resistor R i2 The internal resistance R of battery 2 i1 and transition resistance R i2The combination forms an effective internal resistance R i The terminal voltage of battery 2 is referred to as U.

[0060] The medical device 1 further comprises a DC / DC boost converter 14 connected to the battery contact point 11a. The medical device 1 further comprises a control circuit 15 connected to the output side of the DC / DC boost converter. Thus, the control circuit 15 and other components as described below are powered by the battery 2 via the DC / DC boost converter 14.

[0061] The control circuit 15 includes a processor 151 with corresponding software firmware code, a memory 152, and a voltage measurement circuit 153 for determining and measuring the terminal voltage U of the battery 2. The memory 151 may include both a program memory and a random access memory RAM as data memory, and the program memory stores software and firmware codes for the processor 151. In addition, the control circuit 15 controls the opening and closing of the switch 13. Via the switch 13, a constant resistance test load is implemented as R 测试 A test load may be connected to the battery in parallel with the contact element 11a.

[0062] If switch 13 is closed, the test load R 测试 The current drawn is the test load current I 测试 . Except for the test load current I 测试 In addition, the current I drawn by the medical device 1 is referred to as I. In the initial battery test (as further described below), it is the baseline current I B

[0063] It should be noted that the processor 151, the memory 152 and the voltage measurement circuit 153 may also be integrated in the form of a microcontroller as the core element of the control circuit 15. The control circuit 15 may and usually does further include various other components and functional units generally known in the art.

[0064] The battery-powered medical device 1 in the form of extracorporeal insulin further comprises an actuator 16 in the form of a motor, a display 17 and at least one acoustic and / or tactile indicating device 18 , all of which operate under the control of the control circuit 15 .

[0065] It should be noted that for reasons of clarity and brevity and in order to focus on certain relevant aspects in the context of the present invention, Figure 1 The designs shown in are schematic and simplified. For example, there may be more than one DC / DC boost converter providing the different functional components shown, and the DC / DC boost converter may be omitted. In addition, the test load R 测试 It can be arranged on the output side of the DC / DC boost converter 14. In addition, the test load R 测试This does not have to be achieved with a standard constant resistor, but can be achieved with other circuits such as FETs to form a controlled resistor.

[0066] The control circuit 15 implements a method for powering on the medical device 1, which method also refers to Figure 2 The operation flow starts in step S, where the battery 2 is placed in the battery compartment 11, thereby powering the medical device 1, especially the control circuit 15. In step S01, the voltage U is measured via the voltage measurement circuit 153. In this state, the switch 13 is open, and therefore the measured voltage is the voltage without the test load, U=U 无测试负载 , where I=I B is the baseline current.

[0067] In the subsequent step S02, the test load voltage U 无测试负载 The no-test load voltage threshold U stored in the memory 152 阈值，无测试负载 The comparison is made and the process branch is operated according to the result. 无测试负载 Below the no-test-load voltage threshold U 阈值，无测试负载 , the operation flow starts from step S03. In step S03, an alarm is generated and indicated via the display 17 and the indicating device 18. In addition, the corresponding entry is written to the history memory which is part of the memory 152. Subsequently, the operation flow ends with step E and the power-on is terminated. The alarm can be indicated until the battery 2 is completely exhausted and removed. In an exemplary implementation, the battery 2 is a common commercially available standard battery and there is no test load voltage threshold U 阈值 , 无测试负载 It can be, for example, 1000 mV or 1 V.

[0068] If it is determined in step S02 that there is no test load voltage U 无测试负载 Above the no-test-load voltage threshold U 阈值 , 无测试负载 , the operation flow starts from step S04. In step S04, when the switch 13 is temporarily closed, the voltage U is measured via the voltage measurement circuit 153. Therefore, the measured voltage is the test load voltage, U=U 测试负载 , and the current drawn from battery 2 corresponds to the baseline current I B and the test current I 测试 sum.

[0069] In the following step S05, the voltage difference ΔU=U 无测试负载 -U 测试负载 And the voltage difference is compared with the voltage U without test load 无测试负载 Predefined voltage difference threshold ΔU 阈值For comparison. Voltage difference threshold ΔU 阈值 and without test load voltage U 无测试负载 The relationship between may be stored in or retrieved from the memory 152 in the form of a lookup table, or may be provided in the form of the following equation (which may be a linear equation in particular):

[0070] ΔU 阈值 =f(U 无测试负载 ).

[0071] and is evaluated by the control circuit 15, in particular the processor 151. This aspect will also be discussed further below.

[0072] If it is determined in step S05 that the voltage difference ΔU is higher than the voltage difference threshold ΔU 阈值 , the operation flow starts from step S06. In step S06, an alarm is generated and indicated as previously described in the context of step S03, and the corresponding entry is written to the history memory again. Also in step S03, the operation flow ends with step E and the power-on is terminated.

[0073] If it is determined in step S05 that the voltage difference ΔU is lower than the voltage difference threshold ΔU 阈值 , then the operational flow begins at step S07, where power-up is continued and completed. Step S07 may include performing another battery test as previously described in the general description.

[0074] In the following, the voltage difference threshold ΔU will be discussed in more detail. 阈值 and without test load voltage U 无测试负载 The functional relationship between them.

[0075] When studying the startup behavior of battery-powered medical devices, especially the external insulin pump as described above, it was found that as long as the effective internal resistance R i Satisfy the conditions and can start correctly in any situation

[0076] R i <r i (U0) = k1·U0 + k2 (1a).

[0077] Therefore, to give the effective internal resistance R i , the open circuit voltage U0 needs to meet the following conditions:

[0078]

[0079] In addition, from Figure 1 The following can be seen:

[0080] U0=R i I B+U 无测试负载 (2a),

[0081]

[0082] Wherein equation (2a) applies during the initial battery test with switch 13 open, and equation (2b) applies during the initial battery test with switch 13 closed.

[0083] In the following, the voltage on the output side of the DC / DC boost converter 14 (ie, the supply voltage of the control circuit 15) is referred to as U'. B The (virtual) load resistance seen when B Therefore, equations (2a) and (2b) can be rewritten as

[0084]

[0085] By targeting U 无测试负载 and U 测试负载 Rearranging equations (3a) and (3b) and solving the resulting quadratic equation yields the following result:

[0086]

[0087] Therefore, equations (4a) and (4b) express the voltage U of battery 2: 无测试负载 , U 测试负载 , which can be used as a proxy for the usually unknown open-circuit voltage U0 and the effective internal resistance R i A function of is measured in the medical device 1 in operation.

[0088] In equations (4a, 4b), the effective internal resistance can be replaced by its threshold value, for which the minimum no-test-load voltage U can be obtained by powering up according to equation (1a). 无测试负载，最小值 and minimum test load voltage U 测试负载，最小值 The equation for this is , where the open circuit voltage U0 is the only parameter.

[0089] Figure 3 The figure schematically shows the open circuit voltage U0 plotted as a parameter under the no-test load voltage U 无测试负载 The voltage difference ΔU on 无测试负载 -U 测试负载 Curve A is obtained by directly applying equations (4a) and (4b). In region II above the curve, the medical device 1 cannot be powered on, while in region I below the curve, it can be powered on. Therefore, curve A is respectively calculated based on the voltage without test load U 无测试负载 The voltage difference threshold ΔU 阈值Curve A may be implemented in the control circuit 151 by a mathematical function evaluated by the processor 151 , or may be implemented as a look-up table in the memory 152 .

[0090] Further calculation simplifications as explained below may be used in another embodiment. Instead of curve A, a linear approximation of curve B is used. Curve B may be obtained as a tangent to curve A at a reference value ΔU0. Like curve A, curve B may be implemented in the control circuit 151 by a (linear) mathematical function evaluated by the processor 151, or may be implemented as a lookup table in the memory 152. In an exemplary embodiment, the reference value may be in the range of 1 mV.

[0091] Name List

[0092] 1 Battery-powered medical devices / external insulin pumps

[0093] 11 Battery compartment

[0094] 11a Contact element

[0095] 13 Switch

[0096] 14 DC / DC Boost Converter

[0097] 15 Control Circuit

[0098] 151 Processor

[0099] 152 Memory

[0100] 153 Voltage Measurement Circuit

[0101] 16 Actuator / Motor

[0102] 17 Display

[0103] 18 Indicator

[0104] 2 Batteries

[0105] 21 Ideal Battery

[0106] U0 open circuit voltage

[0107] U Terminal voltage

[0108] U' Voltage at the output of the boost converter

[0109] R i1 Battery internal resistance

[0110] R i2 Transition resistance of contact elements

[0111] R 测试 Test load resistance

[0112] R B Virtual resistor draws baseline current

[0113] ΔU Voltage difference

[0114] ΔU0 Voltage difference reference value

[0115] U 无测试负载 No test load voltage

[0116] U 测试负载 Test load voltage

[0117] U 阈值，无测试负载 Threshold voltage without test load

[0118] ΔU 阈值 Voltage difference threshold

[0119] I Current

[0120] I B Baseline current

[0121] I 测试 Test load current

[0122] k1, k1 constant value

[0123] A, B curves.

Claims

1. A method for powering up a medical device (1) powered by a battery (2), wherein the method comprises performing an initial battery test, the initial battery test comprising the following steps: a) Without the test load R 测试 Determine the no-test-load voltage U of the battery (2) when connected to the battery (2) 无测试负载 ; b) If the no-test load voltage U 无测试负载 Below the predetermined no-test load voltage threshold U 阈值，无测试负载 , an alert is provided and the method is terminated; c) If the no-test load voltage U 无测试负载 Above the no test load voltage threshold U 阈值，无测试负载 , perform the following steps: c1) When the test load R 测试 Determine the test load voltage U of the battery (2) when connected to the battery (2) 测试负载 ; c2) the no-test load voltage U 无测试负载 and the test load voltage U 测试负载 The voltage difference ΔU between the 阈值 For comparison, the voltage difference threshold ΔU 阈值 is based on the no-test load voltage U 无测试负载 predefined; c3) If the voltage difference ΔU is higher than the voltage difference threshold ΔU 阈值 , an alert is provided; The method further comprises: if the voltage difference ΔU is lower than the voltage difference threshold ΔU 阈值 , then execute the subsequent steps of the method, The voltage difference threshold ΔU 阈值 For the no-test load voltage U 无测试负载 A linear function of . 2 . The method according to claim 1 , wherein the test load is a constant resistance test load.

3. The method of claim 1, wherein the initial battery test comprises storing the results of the initial battery test in a history memory (152) of the medical device (1).

4. The method according to claim 1, wherein the method further comprises: If in step c2) it is determined that the voltage difference ΔU is below the voltage difference threshold ΔU 阈值 , a further battery test is performed, wherein the further battery test includes drawing a further test load current to stress the battery (2) to limits expected to occur during normal operation of the medical device (1), and providing an alarm if it is determined that the battery (2) cannot power the medical device (1).

5. The method according to claim 1, wherein the method comprises, before step a): 0) Turn on the power of the medical device.

6. The method of claim 1, wherein the subsequent steps include at least one of a memory check, a communication controller check, a medical device circuit check, a sensor check, an electrode check, an acoustic indicator device test, a tactile indicator device check, and an initialization step of the medical device.

7. A battery-powered medical device (1), the medical device (1) comprising: A battery compartment (11), the battery compartment (11) being designed to detachably accommodate a battery (2) and a contact element (11a) for electrically contacting the battery; Test load R 测试 , the test load R 测试 selectively connectable to the battery (2); A control circuit (15) configured to execute the method according to any one of claims 1-6.

8. The battery-powered medical device (1) according to claim 7, wherein the battery-powered medical device comprises one or more DC / DC boost converters, wherein the DC / DC boost converters power at least some functional units of the medical device (1), wherein the test load R 测试 The contact element (11a) is electrically arranged between the contact element (11a) and the input side of the DC / DC boost converter.

9. The battery-powered medical device (1) according to claim 7 or 8, wherein the voltage difference threshold ΔU 阈值 With the no test load voltage U 无测试负载 The relationship between is stored in the memory (152) of the control circuit (15).

10. A battery-powered medical device (1) according to claim 7 or 8, wherein the control circuit (15) comprises a processor or a computer (151) and a computer-readable storage medium, wherein the computer-readable storage medium comprises instructions which, when executed by the processor or computer (151), cause the processor or computer to control the execution of the method for powering on the medical device (1).

11. The battery-powered medical device (1) according to claim 7 or 8, wherein the medical device is an external insulin pump configured to be carried by a user under clothing and / or attached to the body for a long period of time.

12. A method for determining a voltage U without a test load used in the method according to any one of claims 1 to 6 无测试负载 The voltage difference threshold ΔU 阈值 The method comprises the following steps: (1) Determine the effective internal resistance R through experiments i a functional relationship between the value of and the value of the open circuit voltage U0 at which the battery (2) can power on the medical device (1); (2) Based on the functional relationship determined in step (1), without increasing the test load R 测试 The minimum no-test-load voltage U of the battery (2) that will power up the medical device (1) when connected to the battery (2) 无测试负载，最小值 Determined as a function of the open circuit voltage U0; (3) Based on the functional relationship determined in step (1), the test load R 测试 The minimum test load voltage U of the battery (2) that will power up the medical device (1) when connected to the battery (2) 测试负载，最小值 Determined as a function of the open circuit voltage U0; (4) Based on the minimum no-test load voltage U 无测试负载，最小值 , taking the open circuit voltage U0 as a parameter, according to the minimum no-test load voltage U 无测试负载，最小值 With the minimum test load voltage U 测试负载，最小值 The voltage difference threshold ΔU is calculated by the difference between 阈值 .

13. The method according to claim 12, comprising setting the effective internal resistance R i The functional relationship between the value of and the value of the open circuit voltage U0 is determined to be an approximately linear functional relationship.

14. The method according to claim 12 or claim 13, comprising setting the voltage difference threshold ΔU 阈值 Calculations are linear approximations.

Images