Force sensor device with spherical force interface

Abstract

In a particular embodiment, a force sensor device is disclosed that includes a force compliant element that deforms in response to application of a force to the force sensor device. The force compliant element has a bottom having an outer edge surrounding the force interface. In this embodiment, the outer edge and the force interface extend outwardly from the bottom. The force interface forms a solid spherical shape centered on a centerline of the force compliant element. The spherical force interface is configured to receive an application of a load force and to distribute the load force to the force compliant element. The device also includes one or more sensing elements coupled to the force compliant element and configured to generate a signal indicative of a degree to which the force compliant element deforms in response to a force applied to the force sensor device.

Description

Technical Field

[0001] The invention relates to a force sensor device having a spherical force interface. Background Art

[0002] Force sensors are often used to control or regulate the force applied to a component. In one type of force sensor, the force sensor is positioned so that the force to be measured acts on the sensor. The force sensor can be configured to convert the force measurement into an electrical signal for further control or regulation of the force. This type of force sensor can be used in a variety of applications, such as measuring the braking force of an electromechanical brake in an automobile. For example, a force-compliant element of the force sensor can be coupled to a component of the braking system, and when a force is applied, the force-compliant element temporarily deforms. In this example, the strain on the force-compliant element can be measured and used to generate an electrical signal indicative of the force acting on the component of the braking system. Summary of the Invention

[0003] In a specific embodiment, a force sensor device is disclosed that includes a force compliant element that deforms in response to a force applied to the force sensor device. The force compliant element has a bottom portion having an outer edge surrounding a force interface. In an embodiment, the outer edge and the force interface extend outwardly from the bottom portion. The force interface forms a solid spherical shape centered about a centerline of the force compliant element. The spherical force interface is configured to receive an application of a load force and distribute the load force to the force compliant element. The device also includes one or more sensing elements coupled to the force compliant element and configured to generate a signal indicating the extent to which the force compliant element deforms in response to the force applied to the force sensor device.

[0004] In another embodiment, a method of assembling a force sensor device is disclosed, the method comprising attaching a printed circuit board (PCB) having electronic components to a support structure. The method further comprises electrically coupling the electronic components of the PCB to at least two sensing elements of a force compliant element. In this exemplary embodiment, the at least two sensing elements are configured to measure the force applied to the force sensor device. The method further comprises attaching the support structure to a force compliant element having a bottom portion, the bottom portion having an outer edge surrounding a force interface. In this embodiment, the outer edge and the force interface extend outwardly from the bottom portion. The force interface forms a solid spherical shape centered about a centerline of the force compliant element. The spherical force interface is configured to receive an application of a load force and distribute the load force to the force compliant element.

[0005] The foregoing and other objects, features, and advantages of the invention will be apparent from the following more particular description of exemplary embodiments of the invention, as illustrated in the accompanying drawings, wherein like reference numerals generally represent like parts of exemplary embodiments of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1A is a schematic diagram showing a force sensor device having an annular force interface;

[0007] Figure 1B It shows Figure 1A Schematic diagram of radial movement of a force compliant element of a force sensor device;

[0008] Figure 2A is a schematic diagram showing a side view of a force compliant element having an annular force interface;

[0009] Figure 2B It shows including Figure 2A a schematic diagram of an exploded view of another force sensor device having a force compliant element;

[0010] Figure 2C is a schematic diagram showing the functional test results of lubricated and non-lubricated annular force interfaces;

[0011] Figure 3 is a schematic diagram illustrating a side view of a force compliant element having a spherical force interface according to at least one embodiment of the present disclosure;

[0012] Figure 4A is a schematic diagram showing the Von Mises stress on the annular force interface;

[0013] Figure 4B It shows Figure 3 Schematic diagram of the von Mises stress on the spherical interface;

[0014] Figure 5A is a schematic diagram showing the comparison of FT data of an annular force interface and a non-lubricated force interface;

[0015] Figure 5B It shows Figure 3 Schematic diagram comparing the FT data of the spherical force interface and the non-lubricated force interface;

[0016] Figure 5C is a schematic diagram showing the comparison of FT data of annular force interface and lubricated force interface;

[0017] Figure 5D It shows Figure 3 Schematic diagram comparing the FT data of the spherical force interface and the lubricated force interface;

[0018] Figure 6 is a schematic diagram showing a graph indicating the accuracy of a spherical force interface with nonlinear correction;

[0019] Figure 7Ais a schematic diagram illustrating an example electronic pedal (e-pedal) force sensor device having a spherical force interface according to at least one embodiment of the present disclosure;

[0020] Figure 7B It shows Figure 7A A schematic diagram of another view of an electronic pedal force sensor device;

[0021] Figure 7C It shows Figure 7A a schematic diagram of a cross-sectional view of an electronic pedal force sensor device;

[0022] Figure 8A is a schematic diagram illustrating an example electronic caliper (e-caliper) force sensor device having a spherical force interface in accordance with at least one embodiment of the present disclosure.

[0023] Figure 8B It shows Figure 8A A schematic diagram of another view of an electronic caliper force sensor device;

[0024] Figure 8C It shows Figure 8A A schematic diagram of a cross-sectional view of an electronic caliper force sensor device;

[0025] Figure 9A is a schematic diagram illustrating an example electronic drum (e-drum) force sensor device having a spherical force interface in accordance with at least one embodiment of the present disclosure.

[0026] Figure 9B It shows Figure 9A a schematic diagram of another view of an electronic drum force sensor device;

[0027] Figure 9C It shows Figure 9A a schematic diagram of a cross-sectional view of an electronic drum force sensor device;

[0028] Figure 10 is a flow chart illustrating an implementation of a method for assembling a force sensor device according to an embodiment of the present disclosure; and

[0029] Figure 11 is a flow chart illustrating another implementation of a method for assembling a force sensor device according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0030] For the purpose of describing specific examples, the terms used herein are not intended to limit other examples. Whenever singular forms such as "a", "an" and "the" are used and only a single element is neither explicitly nor implicitly defined as mandatory, other examples may also use plural elements to implement the same function. Similarly, when a function is subsequently described as being implemented using multiple elements, further examples may use a single element or processing entity to implement the same function. It will be further understood that the terms "comprises", "comprising", "includes" and / or "including" specify the presence of the features, wholes, steps, operations, processes, actions, elements and / or parts when used, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, processes, actions, elements, parts and / or any groups thereof.

[0031] It should be understood that when an element is referred to as being "connected" or "coupled" to another element, these elements may be directly connected or coupled or connected or coupled via one or more intermediate elements. If two elements A and B are combined using "or", this should be understood to disclose all possible combinations, i.e., only A, only B, and A and B. An alternative wording for the same combination is "at least one of A and B". The same applies to combinations of two or more elements.

[0032] Therefore, although further examples are capable of various modifications and alternative forms, certain specific examples thereof are shown in the drawings and will be described in detail later. However, this detailed description does not limit other examples to the specific forms described. Other examples may encompass all modifications, equivalents, and alternatives that fall within the scope of the present invention. Throughout the description of the drawings, the same reference numerals represent the same or similar elements, which, when compared to each other, may be implemented identically or in a modified form while providing the same or similar functions.

[0033] The function of a pressure sensor is to convert physical "fluid pressure" into a proportional metric output voltage. This is achieved by using a micro-fused strain gauge (or any other suitable technology) to measure the change in strain field on the sensing element due to the applied pressure. The same (MSG) technology can be used to measure force, as the applied force will also cause a change in the strain field on the sensor's sensing element.

[0034] The primary difference between pressure sensors and force sensors is that pressure is a scalar quantity, while force is a vector quantity. Since force is a vector quantity, the force and support interfaces are more important as they affect the sensor's accuracy. This is becoming increasingly problematic as the current trend toward smaller force sensors for cost and integration reasons.

[0035] For most applications, it is important to measure the load applied in the axial direction and that the sensor should not measure parasitic forces in the radial direction. For a 25kN EMB (Electro Mechanical Brake) ring sensor, there is always a hysteresis of about 1% Fs (full scale) (i.e. the maximum sensor output increment between the upward and downward force curves). For the next generation of EMB sensors, the forces rise to 65kN. The sensor also has to become smaller. This results in a hysteresis of 5% Fs. The hysteresis is mainly caused by the friction coefficient in the force interface. Friction causes a radial load on the bearing / force interface, which is also measured by the sensor. By changing the friction coefficient, not only the amount of hysteresis changes, but also the full-scale output is affected (for example, reducing friction will make the sensing element bend more, resulting in a higher output and therefore a gain shift).

[0036] As will be explained further below, by moving to a "spherical" (or Hertzian) force interface, both of these issues, "gain offset" and "hysteresis," are resolved. With a spherical interface on the centerline of the sensing element / sensor, force engagement will begin at the centerline of the sensor. With this design, there is no radial load on the sensor (independent of the coefficient of friction), which is beneficial. Furthermore, there is no radial movement of the sensing element force interface, and therefore the effect of different coefficients of friction on the sensor's "gain" is negligible.

[0037] To further illustrate, Figure 1A illustrates a schematic diagram showing a 25 kN EMB ring force sensor device 100, and Figure 1B Explained and demonstrated Figure 1A Schematic diagram of the radial movement of the sensing element of the EMB ring force sensor. Figure 1A Device 100 includes a force compliant element 102 that is configured to deform in response to a force applied to the force sensor device. In a specific embodiment, force compliant element 102 has a first surface that is arranged to receive a first force. The force compliant element is connected to an interface structure 118 that is arranged to receive a second force in a direction opposite to the first force, so that force compliant element 102 deforms in response to the first force and the second force being applied to force sensor device 100. Force compliant element 102 can be a piece of material, such as metal or plastic, that deforms in response to the application of a force. For example, force compliant element 102 can be an annular metal disk.

[0038] Figure 1A Device 100 also includes sensing elements (not shown) coupled to force compliant element 102. Each of the sensing elements is configured to generate a signal indicating the extent to which force compliant element 102 deforms in response to a force applied to device 100. The sensing elements may be microfused silicon strain gauges (MSGs).

[0039] also, Figure 1A The device 100 of FIG1 also includes a printed circuit board (PCB) (110) on which electronic components (e.g., integrated circuits and passive components (such as resistors, capacitors, etc.)) are positioned and configured to receive signals from the sensing elements. In the force sensor device (100) of FIG1 , the support structure 108 has a surface coupled to the PCB 110. The support structure can be made of many types of materials suitable for supporting the PCB 110, such as metals and plastics. Figure 1A In the example shown, support structure 108 is positioned within the stack of components of force sensor device 100 to rest on force compliant element 102. Support structure 108 may also include an opening (not shown) through which components of the PCB may be coupled to the sensing element. In this example, the opening in support structure 108 may align with the location of pads on PCB 110 so that contacts on the sensing element may engage the pads on PCB 110.

[0040] Figure 1A The device 100 further includes a sensor housing 112 covering the PCB 110 . The sensor housing 112 is designed to protect the electronic components of the force sensor device 100 . Figure 1A The device 100 also includes an environmental sealing ring 106, which, when placed between the sensor housing 112 and the force compliant element 102, ensures that the internal components of the force sensor device 100 are protected. Figure 1A In the example shown, the environmental seal ring is an O-ring, but readers skilled in the art will recognize that many other shapes and configurations (such as D-rings and potting compounds) can be used to provide a seal with the environment. Use of an environmental seal allows the sensor housing to be assembled and sealed to the force compliant element without having to weld or otherwise couple the inner edge of the sensor housing to the force compliant element.

[0041] Figure 1A The device 100 also includes an electrical connector assembly aligned for positioning within the opening of the sensor housing 112. Figure 1A In the example of FIG, the electrical connector assembly includes a plurality of electrical connection pins 117 for transmitting signals to an external component (not shown). The electrical connector assembly also includes a plurality of mechanical orientation features 119 for aligning the device with the external component (not shown).

[0042] also, Figure 1AThe device 100 includes an interface structure 118 that distributes the load to the force compliant element 102 when the interface structure 118 is attached to the force compliant element 102. Figure 1A In the example shown, interface structure 118 is a ring or interface ring that, when coupled to force compliant element 102, evenly distributes the load to force compliant element 102 so that the sensing element can accurately measure the load on the force compliant element. Interface structure 118 can also be used to create an interface for coupling force sensor device 100 to a component that provides force to force compliant element 102. For example, interface structure 118 can be used to secure device 100 to a caliper of an electromechanical brake system.

[0043] exist Figure 1A In the example of FIG. 1 , force-compliant element 102 includes an annular force interface 105 for coupling to an external component that applies the force or load to be measured. For example, force-compliant element 102 can be coupled to a piston of an electromechanical brake system. As described above, the application of these forces can cause force-compliant element 102 to temporarily deform. In this example, a sensing element can generate an electrical signal having characteristics proportional to the amount of deformation in force-compliant element 102.

[0044] exist Figure 1A In the example shown, the annular force interface 105 is positioned diametrically away from the centerline of the sensor. By increasing the load, the force interface will move not only in the axial direction, but also in the radial direction. This will mean that radial forces will also act on the sensing element. The level of this force depends on the coefficient of friction (which may vary over life and between calibration at the manufacturing site and customer application), which will affect the accuracy of the sensor.

[0045] To further illustrate, Figure 2A A schematic diagram illustrating a side view of a force compliant element 202 having an annular force interface 205 is illustrated. Annular force interface 205 is a surface for coupling force compliant element 202 to an external component that applies a force or load to be measured. Force compliant element 202 also includes a support surface 203 for coupling to an interface structure of a force sensor device.

[0046] To further illustrate, Figure 2B Explained and demonstrated including Figure 2A Schematic diagram of an exploded view of another force sensor device of a force compliance element. Figure 2B The device 200 includes many components, which are similar to Figure 1A Components of device 100, but configured and shaped to produce a sensor assembly that is more cylindrical in shape.

[0047] Figure 2BDevice 200 includes a force-compliant element 202 arranged to receive oppositely directed forces. In a particular embodiment, force-compliant element 202 is a component of a material (such as metal or plastic) that deforms in response to the application of force. For example, force-compliant element 202 can be a button-shaped metal disc.

[0048] Figure 2B The device 200 also includes four sensing elements 204 coupled to the force compliant element 202. Each of the sensing elements 204 is configured to generate a signal indicating the extent to which the force compliant element 202 deforms in response to the application of oppositely directed forces. These signals from the sensing elements 204 can be transmitted to a printed circuit board (PCB) 216 via electrical connections (not shown) and can be used by the PCB 216 and other components coupled to the PCB. In a specific embodiment, the sensing elements are microfused silicon strain gauges (MSGs). To measure the amount of force applied to the force compliant element, the sensing elements can be evenly distributed on a circle on the top surface of the force compliant element 202.

[0049] PCB 216 includes electronic components (integrated circuits and passive components such as resistors, capacitors, etc.) positioned and configured to receive signals from sensing element 204 .

[0050] exist Figure 2B In the force sensor device 200 of FIG. 1 , the support structure 208 has a surface coupled to the PCB 216. The support structure can be made of many types of materials suitable for supporting the PCB 216, such as metal and plastic. Figure 2B In the example shown, support structure 208 is positioned in the stack of components of force sensor device 200 to rest on force compliant element 202. For example, in an assembled state, an outer edge of support structure 208 is coupled to outer edge 292 of force compliant element 202. Support structure 208 may also include an opening (not shown) through which components of the PCB may be coupled to the sensing element.

[0051] also, Figure 2B The device 200 also includes a sensor housing 212 covering the PCB 216 and the support structure 208. The sensor housing 212 is designed to protect the electronic components of the force sensor device 200 and receive the reaction force for force measurement. Although not shown, Figure 2B The device 200 may also include an electrical connector aligned for positioning within the opening of the sensor housing 212. In the assembled state, an outer edge of the sensor housing 212 is coupled to an outer edge 290 of the force compliant element 202.

[0052] exist Figure 2A and Figure 2B In this example, the sensor device is reduced in size to reduce sensor cost. In addition, the full-scale applied force is increased to 65 kN. Figure 2B The results in indicate a hysteresis of approximately 5% Fs and a gain offset of 5% Fs.

[0053] To further illustrate, Figure 3 1 illustrates a schematic diagram showing a side view of a force compliant element 302 having a spherical force interface 305. The force compliant element 302 is configured to deform in response to the application of a force. Figure 3 In the example of , the force compliant element 302 has a bottom portion 349 having an outer edge 347 surrounding the force interface 305. The outer edge 347 and the force interface 305 extend outward from the bottom portion 349 and are separated by a gap 345. The force interface 305 forms a solid spherical shape centered on the centerline 330 of the force compliant element 302. The force interface 305 is configured to receive an application of a load force and distribute the load force to the force compliant element 302. The center 306 of the force interface 305 is configured to contact an external component to receive the application of the load force. In certain embodiments, the force interface includes a flat surface for coupling with an external component. In other embodiments, the force interface includes a parabolic surface for coupling with an external component.

[0054] With the lack of center Figure 1A and Figure 2A Compared to the annular force interface of FIG. 304 , the center 306 of the spherical force interface 305 is solid and continuous, which allows the load force to be distributed to the center of the force compliant element. In an alternative embodiment of the force compliant element with a spherical force interface, the outer edge of the force compliant element and the force interface extend outward from the bottom portion and are not separated by a gap. In this alternative embodiment, the force interface is connected to and extends from the outer edge of the force compliant element.

[0055] To further illustrate, Figure 4A The paper describes the annular force interface (such as Figure 1A or Figure 2A Schematic diagram of the von Mises stress on one of the annular interfaces in [1]. Figure 4B Explained and demonstrated Figure 3 Schematic diagram of the von Mises stress on the spherical force interface 305.

[0056] At low loads, a sensor with a spherical interface will experience a load at its centerline. As the load increases, the contact area increases. The radius of the spherical interface is optimized to avoid plastic deformation in the force interface. This is beneficial in preventing yielding in the rest of the sensor. Compared to an annular force interface, a spherical force interface results in a larger moment arm between the force interface and the support interface.

[0057] To further illustrate, Figure 5Ais a schematic diagram showing a comparison of FT data of an annular force interface and a non-lubricated force interface. Figure 5B It shows Figure 3 Schematic illustration of the comparison of the FT data of the spherical force interface and the non-lubricated force interface. Figure 5C Schematic diagram showing the comparison of FT data of an annular force interface and a lubricated force interface. Figure 5D It shows Figure 3 Schematic illustration of the comparison of the FT data of the spherical force interface and the lubricated force interface.

[0058] To further illustrate, Figure 6 A schematic diagram showing a graph indicating the accuracy of a spherical / Hertzian interface with nonlinearity correction is illustrated. For a spherical / Hertzian interface, nonlinearity can be largely compensated in the ASIC, resulting in Figure 6 The following precisions are shown in .

[0059] To further illustrate, Figure 7A A schematic diagram illustrating an electronic pedal (e-pedal) force sensor device 700 having a spherical force interface 705 is set forth. Figure 7B Shown Figure 7A Another view of the pedal force sensor device, and Figure 7C Explained Figure 7A A cross-sectional view of a pedal force sensor device. An automotive electronic pedal (e-pedal) force sensor is designed to measure the loads applied to the brake, accelerator, and clutch pedals during acceleration, deceleration, and transmission shift events.

[0060] Device 700 includes a force compliant element 702 arranged to receive oppositely directed forces. In particular embodiments, force compliant element 702 is a piece of material, such as metal or plastic, that deforms in response to the application of force.

[0061] Device 700 also includes sensing elements (not shown) coupled to force compliant element 702. Each of the sensing elements is configured to generate a signal indicating the extent to which force compliant element 702 deforms in response to application of oppositely directed forces. These signals from the sensing elements can be transmitted to printed circuit board (PCB) 710 via electrical connection (750) and can be used by PCB 710 and other components coupled to the PCB. In a specific embodiment, the sensing elements are microfused silicon strain gauges (MSGs). To measure the amount of force applied to force compliant element 702, the sensing elements can be evenly distributed on a circle on the top surface of force compliant element 702.

[0062] PCB 710 includes electronic components (integrated circuits and passive elements (such as resistors, capacitors, etc.)) positioned and configured to receive signals from the sensing elements.

[0063] In force sensor device 700, support structure 708 has a surface coupled to PCB 710. Support structure 708 can be made of many types of materials suitable for supporting PCB 710, such as metal and plastic. In this example, support structure 708 is positioned in the stack of components of force sensor device 700 to rest on force compliant element 702. For example, in an assembled state, an outer edge of support structure 708 is coupled to outer edge 792 of force compliant element 702. Support structure 708 can also include an opening (not shown) through which components of the PCB can be coupled to the sensing element.

[0064] Device 700 also includes a sensor housing assembly 761 having a sensor housing 770 covering PCB 710 and support structure 708. Sensor housing 770 is designed to protect the electronic components of force sensor device 700 and receive reaction forces for force measurement. In an assembled state, the outer edge of sensor housing 770 is coupled to the outer edge 790 of force-compliant element 702. Force-compliant element 702 also includes a support surface 754 for coupling to an interface structure and receiving reaction forces.

[0065] Sensor housing assembly 761 also includes a sensor cover portion 780 for housing an electrical connector 788. Electrical connector 788 couples to and receives electrical signals from the electronic components of the PCB. Electrical connector 788 is configured to couple to and transmit signals from external components to the PCB. An environmental seal 799 is positioned between sensor cover portion 780 and sensor housing 770.

[0066] Force compliant element 702 has a bottom portion 749 having an outer edge 747 surrounding force interface 705. Outer edge 747 and force interface 705 extend outwardly from bottom portion 749 and are separated by a gap 745. Force interface 705 forms a solid spherical shape centered about a centerline (not shown) of force compliant element 702. Force interface 705 is configured to receive a load force and distribute the load force to force compliant element 702. In this example, force interface 706 includes a parabolic surface for coupling with an external component for receiving a load force.

[0067] For example, force interface 705 can be coupled to a component of an automotive electronic pedal system so that device 700 can measure and report the force applied to the component. Figure 7C As can be seen in the example of FIG, outer edge 747 of force compliant element 702 extends beyond force interface 705 in a direction perpendicular to a plane parallel to a bottom portion 749 of the force compliant element. Readers skilled in the art will recognize that the force interface can be optimized for a specific application by fine-tuning the radius of the spherical shape.

[0068] To further illustrate, Figure 8A A schematic diagram illustrating an electronic caliper (e-caliper) force sensor device 800 having a spherical force interface 805 is set forth. Figure 8B Shown Figure 8A Another view of the electronic caliper force sensor device, and Figure 8C Explained Figure 8A A cross-sectional view of an electronic caliper force sensor device. Automotive electromechanical caliper brake systems (electronic calipers) force sensors provide monitoring and control for electromechanical caliper brake systems.

[0069] Device 800 includes a force compliant element 802 arranged to receive oppositely directed forces. In particular embodiments, force compliant element 802 is a piece of material, such as metal or plastic, that deforms in response to the application of force.

[0070] The device 800 also includes sensing elements (804) coupled to the force-compliant element 802. Each of the sensing elements 804 is configured to generate a signal indicating the extent to which the force-compliant element 802 deforms in response to the application of oppositely directed forces. These signals from the sensing elements 804 can be transmitted to a printed circuit board (PCB) 810 via electrical connectors (not shown) and can be used by the PCB 810 and other components coupled to the PCB. In a specific embodiment, the sensing elements are microfused silicon strain gauges (MSGs). To measure the amount of force applied to the force-compliant element 802, the sensing elements 804 can be evenly distributed on a circle on the top surface of the force-compliant element 802.

[0071] PCB 810 includes electronic components (integrated circuits and passive elements (such as resistors, capacitors, etc.)) positioned and configured to receive signals from the sensing elements.

[0072] In force sensor device 800, support structure 808 has a surface coupled to PCB 810. Support structure 808 can be made of many types of materials suitable for supporting PCB 810, such as metal and plastic. In this example, support structure 808 is positioned in the stack of components of force sensor device 800 to rest on force compliant element 802. For example, in an assembled state, an outer edge of support structure 808 is coupled to outer edge 892 of force compliant element 802. Support structure 808 can also include an opening (not shown) through which components of PCB 810 can be coupled to sensing element 804.

[0073] Furthermore, device 800 includes a sensor housing assembly 861 having a sensor housing 870 covering PCB 810 and support structure 808. Sensor housing 870 is designed to protect the electronic components of force sensor device 800 and to receive reaction forces for force measurement. In the assembled state, the outer edge of sensor housing 870 is coupled to the outer edge 890 of force compliant element 802.

[0074] The sensor housing assembly 861 also includes a sensor cover portion 880 for housing an electrical connector 888. The electrical connector 888 is coupled to and receives electrical signals from the electronic components of the PCB. The electrical connector 888 is configured to couple to and transmit signals from external components to the PCB.

[0075] Force compliant element 802 has a bottom portion 849 having an outer edge 847 surrounding force interface 805. Outer edge 847 and force interface 805 extend outward from bottom portion 849 and are separated by a gap 845. In an alternative embodiment of a force compliant element having a spherical force interface, the outer edge of the force compliant element and the force interface extend outward from the bottom portion and are not separated by a gap. In this alternative embodiment, the force interface is connected to and extends from the outer edge of the force compliant element.

[0076] The force interface 805 is formed into a solid spherical shape centered about a centerline (not shown) of the force compliant element 802. The force interface 805 is configured to receive a load force and distribute the load force to the force compliant element 802. The force compliant element 802 also includes a support surface 854 for coupling to an interface structure and receiving a reaction force. For example, the force interface 805 can be coupled to a component of an automotive electromechanical caliper brake system (electronic caliper) so that the device 800 can measure and report the force applied to the component. A reader of ordinary skill in the art will recognize that the force interface can be optimized for a specific application by fine-tuning the radius of the spherical shape.

[0077] To further illustrate, Figure 9A A schematic diagram illustrating an example electronic drum (e-drum) force sensor apparatus 900 having a spherical force interface 905 is set forth. Figure 9B Shown Figure 9A Another view of the electronic drum force sensor device, and Figure 9C Explained Figure 9A Cross-sectional view of an electronic drum force sensor device. Automotive electromechanical drum brake system (electronic drum) force sensors provide monitoring and control of electromechanical drum brake systems.

[0078] Device 900 includes a force compliant element 902 arranged to receive oppositely directed forces. In particular embodiments, force compliant element 902 is a piece of material (such as metal or plastic) that deforms in response to the application of force.

[0079] Device 900 also includes sensing elements (not shown) coupled to force-compliant element 902. Each of the sensing elements is configured to generate a signal indicating the extent to which force-compliant element 902 deforms in response to application of oppositely directed forces. These signals from the sensing elements can be transmitted to printed circuit board (PCB) 910 via electrical connectors (not shown) and can be used by PCB 910 and other components coupled to the PCB. In a specific embodiment, the sensing elements are microfused silicon strain gauges (MSGs). To measure the amount of force applied to force-compliant element 902, the sensing elements can be evenly distributed on a circle on the top surface of force-compliant element 902.

[0080] PCB 910 includes electronic components (integrated circuits and passive elements (such as resistors, capacitors, etc.)) positioned and configured to receive signals from the sensing elements.

[0081] In force sensor device 900, support structure 908 has a surface to which PCB 910 is coupled. Support structure 908 can be made of many types of materials suitable for supporting PCB 910, such as metal and plastic. In this example, support structure 908 is positioned in the stack of components of force sensor device 900 to rest on force compliant element 902. Support structure 908 can also include openings (not shown) through which components of PCB 910 can be coupled to the sensing element.

[0082] Additionally, device 900 includes a sensor housing 970 that covers PCB 910 and support structure 908. Sensor housing 970 is designed to protect the electronic components of force sensor device 900 and receive reaction forces for force measurement. In an assembled state, sensor housing 970 is coupled to force-compliant element 902 such that any force applied to housing 970 is then applied or "flows" through the housing and into contact with force-compliant element 902. For example, housing 970 includes a support surface 954 for coupling to an interface structure and receiving reaction forces.

[0083] The device 900 also includes a sensor cover 980 for housing an electrical connector 988. The electrical connector 988 is coupled to and receives electrical signals from the electronic components of the PCB. The electrical connector 988 is configured to couple to and transmit signals from external components to the external components.

[0084] The force compliant element 902 has a bottom portion 949 having an outer edge 947 surrounding a force interface 905. The outer edge 947 and the force interface 905 extend outwardly from the bottom portion 949 and are separated by a gap 945. The force interface 905 forms a solid spherical shape centered about a centerline (not shown) of the force compliant element 902. The force interface 905 is configured to receive a load force and distribute the load force to the force compliant element 902. For example, the force interface 905 can be coupled to a component of an automotive electromechanical drum brake system (electronic drum) so that the device 900 can measure and report the force applied to the component. Readers in the art will recognize that the force interface can be optimized for a specific application by fine-tuning the radius of the spherical shape.

[0085] To further illustrate, Figure 10 A flow chart illustrating an implementation of a method for assembling a force sensor apparatus according to an embodiment of the present disclosure is set forth. Figure 10 The method includes attaching 1002 a printed circuit board (PCB) having electronic components to a support structure. Attaching 1002 the printed circuit board (PCB) having electronic components to the support structure may be accomplished by soldering to or applying an adhesive, tape, or glue to the PCB (e.g., Figure 7C PCB 710; Figure 8C PCB 810 and Figure 9C PCB 910) and the bottom and support structure (e.g., Figure 7C Support structure 708; Figure 8C Support structure 808; and Figure 9C support structure 908).

[0086] Figure 10 The method further includes electrically coupling 1004 the electronic components of the PCB to at least two sensing elements on the force compliant element, the at least two sensing elements being configured to measure the force applied to the force sensor device. Electrically coupling 1004 the electronic components of the PCB to the at least two sensing elements on the force ring may be accomplished by connecting leads from the PCB to the force compliant element (e.g., Figure 7C force compliant element 702; Figure 8C force compliant element 802; and Figure 9C The sensing element on the force compliant element 902).

[0087] Figure 10The method also includes attaching 1006 a support structure to a force-compliant element, the force-compliant element including a force interface having a spherical shape radiating outward from a centerline of the force-compliant element. The force-compliant element has a bottom portion having an outer edge surrounding the force interface. In this embodiment, the outer edge and the force interface extend outward from the bottom portion and are separated by a gap. The force interface forms a solid spherical shape centered on the centerline of the force-compliant element. The spherical force interface is configured to receive an application of a load force and distribute the load force to the force-compliant element. The device also includes one or more sensing elements coupled to the force-compliant element and configured to generate a signal indicating the extent to which the force-compliant element deforms in response to a force applied to the force sensor device. Attaching 1006 the support structure to the force-compliant element can be achieved by welding, gluing, or otherwise coupling the force-compliant element and the support structure.

[0088] To further illustrate, Figure 11 Set forth is a flow chart illustrating another implementation of a method for assembling a force sensor apparatus according to an embodiment of the present disclosure. Figure 11 The method is similar to Figure 10 The method in Figure 11 The method also includes Figure 10 All components.

[0089] also, Figure 11 The method further includes positioning 1102 the sensor housing assembly over the electronic components and the force compliant element of the PCB. Positioning 1102 the sensor housing assembly over the electronic components and the force compliant element of the PCB may be accomplished by positioning the sensor housing assembly (e.g., Figure 7C sensor housing assembly 761; Figure 8C The sensor housing assembly 861) is placed above the PCB.

[0090] also, Figure 11 The method further includes attaching 1104 the sensor housing assembly to the force compliant element. Attaching 1104 the sensor housing assembly to the force compliant element may be accomplished by welding or applying adhesive, tape, or glue to the bottom of the sensor housing assembly to couple the sensor housing assembly and the force compliant element.

[0091] The flowcharts and schematic diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of devices and methods according to various embodiments of the present disclosure. In some alternative implementations, the functions noted in the blocks or steps of the method may not occur in the order noted in the figures. For example, depending on the functions involved, two blocks shown in succession may actually be executed substantially simultaneously, or the blocks may sometimes be executed in the reverse order.

[0092] The advantages and features of the present disclosure can be further described by the following statements:

[0093] 1. A force sensor device comprising: a force-compliant element that deforms in response to a force applied to the force sensor device, the force-compliant element having a bottom portion, the bottom portion having an outer edge surrounding a force interface, the outer edge and the force interface extending outwardly from the bottom portion, the force interface forming a solid spherical shape centered about a centerline of the force-compliant element, the spherical force interface configured to receive an application of a load force and distribute the load force to the force-compliant element; and one or more sensing elements coupled to the force-compliant element and configured to generate a signal indicative of the extent to which the force-compliant element deforms in response to a force applied to the force sensor device.

[0094] 2. The apparatus of statement 1 , wherein an outer edge of the force compliant element extends beyond the force interface in a direction perpendicular to a plane parallel to the bottom portion of the force compliant element.

[0095] 3. The apparatus of statement 1 or 2, wherein a center of the force interface is configured to contact an external component to receive application of a load force.

[0096] 4. The apparatus of any one of statements 1-3, further comprising: a printed circuit board configured to receive signals from the one or more sensing elements; and a support structure having a surface to which the printed circuit board is coupled.

[0097] 5. The apparatus of any one of statements 1 to 4, wherein the one or more sensing elements comprise one or more gauges.

[0098] 6. The apparatus of any one of statements 1-5, wherein the outer edge and the force interface are separated by a gap.

[0099] 6. The apparatus of any of statements 1-5, further comprising a sensor housing coupled to the force compliant element and covering the PCB.

[0100] 7. The apparatus of any of statements 1-6, further comprising a sensor housing coupled to the force compliant element and covering the PCB and the support structure.

[0101] 8. The device of any of statements 1-7, wherein the force sensor device is an electronic caliper force sensor device.

[0102] 9. The device of any of statements 1-7, wherein the force sensor device is an electronic pedal force sensor device.

[0103] 10. The device of any of statements 1-7, wherein the force sensor device is an electronic drum force sensor device.

[0104] 11. A method for assembling a force sensor device, the method comprising: attaching a printed circuit board (PCB) having electronic components to a support structure; electrically coupling the electronic components of the PCB to at least two sensing elements on a force-compliant element, the at least two sensing elements being configured to measure the force applied to the force sensor device; and attaching the support structure to the force-compliant element, the force-compliant element having a bottom portion, the bottom portion having an outer edge surrounding a force interface, the outer edge and the force interface extending outward from the bottom portion, the force interface forming a solid spherical shape centered on a centerline of the force-compliant element, the spherical force interface being configured to receive application of a load force and distribute the load force to the force-compliant element.

[0105] 12. The method of statement 11, further comprising: positioning a sensor housing assembly over the electronic components of the PCB and the force compliant element; and attaching the sensor housing assembly to the force compliant element.

[0106] 13. The method of any of statements 11-12, wherein the one or more sensing elements comprise one or more gauges.

[0107] 14. The method of any of statements 11-13, wherein an outer edge of the force compliant element extends beyond the force interface in a direction perpendicular to a plane parallel to the bottom portion of the force compliant element.

[0108] 15. The method of any of statements 11-14, wherein a center of the force interface is configured to contact an external component to receive application of a load force.

[0109] 16. The method of any of statements 11-15, wherein the outer edge and the force interface are separated by a gap.

[0110] 17. The method of any of statements 11-16, wherein the force sensor device is an electronic caliper force sensor device.

[0111] 18. The method of any of statements 11-16, wherein the force sensor device is an electronic pedal force sensor device.

[0112] 19. The method of any of statements 11-16, wherein the force sensor device is an electronic drum force sensor device.

[0113] This document may describe one or more embodiments by means of method steps that demonstrate the execution of specific functions and their relationships. For ease of description, the boundaries and order of these functional building blocks and method steps have been arbitrarily defined herein. As long as the specific functions and relationships are properly performed, alternative boundaries and orders can be defined. Therefore, any such alternative boundaries or orders are within the scope and spirit of the claims. In addition, for ease of description, the boundaries of these functional building blocks have been arbitrarily defined. As long as certain important functions are properly performed, alternative boundaries can be defined. Similarly, flowchart blocks can also be arbitrarily defined herein to illustrate certain important functions.

[0114] To the extent used, the flowchart block boundaries and sequence could have been defined otherwise and still perform certain significant functionality. Therefore, such alternative definitions of functional building blocks and flowchart blocks and sequences are within the scope and spirit of the claims. One of ordinary skill in the art will also recognize that the functional building blocks and other illustrative blocks, modules, and components herein can be implemented as shown or by discrete components, application specific integrated circuits, processors executing appropriate software, etc., or any combination thereof.

[0115] Although specific combinations of different functions and features of one or more embodiments have been explicitly described herein, other combinations of these features and functions are also possible. The present disclosure is not limited to the specific examples disclosed herein, and expressly incorporates these other combinations.

Claims

1. A force sensor device comprising: a force compliant element that deforms in response to a force applied to the force sensor device, the force compliant element having a base portion having an outer edge surrounding a force interface, the outer edge and the force interface extending outwardly from the base portion, the force interface forming a solid spherical shape centered about a centerline of the force compliant element, the spherical force interface configured to receive an application of a load force and distribute the load force to the force compliant element; as well as One or more sensing elements are coupled to the force compliant element and configured to generate a signal indicative of an extent to which the force compliant element deforms in response to a force applied to the force sensor device.

2. The device according to claim 1, wherein An outer edge of the force compliant element extends beyond the force interface in a direction perpendicular to a plane parallel to the bottom portion of the force compliant element.

3. The device according to claim 1, wherein The center of the force interface is configured to contact an external component to receive application of a load force.

4. The apparatus according to claim 1, further comprising: a printed circuit board configured to receive signals from the one or more sensing elements; as well as A support structure has a surface to which the printed circuit board is coupled.

5. The apparatus according to claim 1, wherein The one or more sensing elements include one or more gauges.

6. The apparatus according to claim 1, wherein The outer edge and the force interface are separated by a gap.

7. The apparatus of claim 4, further comprising a sensor housing assembly coupled to the force compliant element and covering the printed circuit board.

8. The apparatus according to claim 1, wherein The force sensor device is an electronic caliper force sensor device.

9. The apparatus according to claim 1, wherein The force sensor device is an electronic pedal force sensor device.

10. The apparatus according to claim 1, wherein The force sensor device is an electronic drum force sensor device.

11. A method of assembling a force sensor apparatus, the method comprising: attaching a printed circuit board (PCB) having electronic components to a support structure; electrically coupling electronic components of the PCB to at least two sensing elements on a force compliant element, the at least two sensing elements being configured to measure a force applied to the force sensor device; as well as The support structure is attached to a force-compliant element having a bottom portion having an outer edge surrounding a force interface, the outer edge and the force interface extending outward from the bottom portion, the force interface forming a solid spherical shape centered about a centerline of the force-compliant element, the spherical force interface being configured to receive application of a load force and distribute the load force to the force-compliant element.

12. The method according to claim 11, further comprising: positioning a sensor housing assembly over the electronic components of the PCB and the force compliant element; as well as The sensor housing assembly is attached to the force compliant element.

13. The method according to claim 11, wherein: The one or more sensing elements include one or more gauges.

14. The method according to claim 11, wherein An outer edge of the force compliant element extends beyond the force interface in a direction perpendicular to a plane parallel to the bottom portion of the force compliant element.

15. The method according to claim 11, wherein A center of the force interface is configured to contact an external component to receive application of the load force.

16. The method according to claim 11, wherein The outer edge and the force interface are separated by a gap.

17. The method according to claim 11, wherein The force sensor device is an electronic caliper force sensor device.

18. The method according to claim 11, wherein The force sensor device is an electronic pedal force sensor device.

19. The method according to claim 11, wherein The force sensor device is an electronic drum force sensor device.

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