Force sensors, electromechanical brake systems and automobiles

Abstract

The present application relates to the field of automobile technology, and provides a force sensor, an electronic mechanical brake system and an automobile, wherein the force sensor includes a load-bearing member, a plurality of strain gauges, the load-bearing member includes a sensing area, a first groove is provided on the load-bearing member, and the first groove surrounds and surrounds the sensing area; each strain gauge includes a first side and a second side connected to each other, and the length of the first side is greater than the length of the second side; wherein the strain gauges are arranged in an interval around the center of the sensing area in the sensing area, and the first side and the second side of each two adjacent strain gauges are staggered toward the center of the sensing area. The present application can improve the accuracy of the output result of the force sensor and improve the performance stability of the force sensor.

Description

Technical Field

[0001] The present application relates to the field of automobile technology, and in particular to a force sensor, an electromechanical braking system and an automobile. Background Art

[0002] The braking system is one of the important components of a car, which is directly related to the comprehensive performance of the car and the safety of life and property of the user. The automobile braking system includes service brakes, parking brakes and auxiliary brakes. At present, the air brake system of heavy motor vehicles often uses force displacement sensors to directly detect the braking force. However, in the prior art, the force sensor is prone to azimuth error, and the azimuth error is large. Therefore, when the force applied to the force sensor deviates from the preset direction, the data error of the force sensor will change greatly, resulting in low accuracy of the output result of the force sensor and poor performance stability of the force sensor. Summary of the invention

[0003] The present application provides a force sensor, an electronic mechanical braking system and a car, which can improve the accuracy of the output result of the force sensor and improve the performance stability of the force sensor.

[0004] In order to solve the above technical problems, the present application provides a force sensor, which includes a load-bearing member and multiple strain gauges. The load-bearing member includes a sensing area. A first groove is provided on the load-bearing member, and the first groove surrounds and encloses the sensing area; each strain gauge includes a first side edge and a second side edge that are connected to each other, and the length of the first side edge is greater than the length of the second side edge; wherein the strain gauges are arranged in the sensing area at intervals around the center of the sensing area, and the first side edges and the second side edges of each two adjacent strain gauges are staggered toward the center of the sensing area.

[0005] The load-bearing member includes a mounting end surface and a supporting end surface that are arranged opposite to each other, the sensing area and the first groove are both arranged on the mounting end surface; the supporting end surface is provided with a second groove, and the first groove and the second groove are arranged in alignment.

[0006] The mounting end surface is further provided with a first force-bearing area and a third groove; the third groove surrounds and encloses the first groove, and the first force-bearing area is located on the outer side of the third groove facing away from the sensing area.

[0007] Among them, the supporting end face is provided with a second force-bearing area and a fourth groove; the fourth groove surrounds and encloses the second groove, and the second force-bearing area is located between the second groove and the fourth groove; along the positive projection direction of the mounting end face toward the supporting end face, the projection of the first force-bearing area is at least partially located outside the second force-bearing area.

[0008] Among them, the load-bearing member includes a mounting end surface, and the sensing area and the first groove are both arranged on the mounting end surface; a mounting protrusion is also protruding on the mounting end surface, which surrounds and encloses the first groove, and a supporting step surface is provided on the inner side of the mounting protrusion facing the sensing area; the force sensor also includes a circuit board, which is electrically connected to the strain gauge; the circuit board is located in the mounting protrusion and supported on the supporting step surface.

[0009] The mounting end surface is also provided with a first force-bearing area and a third groove; the third groove surrounds and encloses the mounting protrusion, and the first force-bearing area is located on the outer side of the third groove facing away from the mounting protrusion.

[0010] Among them, a fixed step is also provided on the outer side of the mounting protrusion facing away from the sensing area; the force sensor also includes a shell, which is installed on the mounting end surface, wherein an accommodating space for accommodating the circuit board is formed between the shell and the mounting end surface; the shell includes a fixed side panel, and the end of the fixed side panel is fixed to the fixed step.

[0011] The load-bearing member is also provided with a mounting hole, and the sensing area surrounds the mounting hole; the outer shell includes a top plate and a mounting column connected to the top plate, the fixed side plate is formed by extending from the periphery of the top plate, and the mounting column and the fixed side plate are located on the same side of the top plate; wherein the mounting column is installed in the mounting hole, and a sealing ring is also provided between the side wall of the mounting column and the inner wall of the mounting hole.

[0012] Each strain gauge is rectangular; the strain gauges are arranged in a circle with the first side and the second side alternately facing the center of the sensing area and surrounding the center of the sensing area in a uniformly spaced manner.

[0013] In order to solve the above technical problems, the present application further provides an electronic mechanical braking system, which includes the above force sensor.

[0014] In order to solve the above technical problems, the present application further provides a car, which includes the above electronic mechanical braking system.

[0015] The beneficial effects of the present application are as follows: the force sensor of the present application includes a load-bearing member and a plurality of strain gauges, the load-bearing member includes a sensing area, a first groove is provided on the load-bearing member, and the first groove surrounds and encloses the sensing area; each strain gauge includes a first side edge and a second side edge connected to each other, and the length of the first side edge is greater than the length of the second side edge; wherein the strain gauges are arranged in the sensing area in an interval arrangement around the center of the sensing area, and the first side edge and the second side edge of each two adjacent strain gauges are arranged in an alternating manner toward the center of the sensing area. The first groove surrounding and enclosing the sensing area is provided on the load-bearing member, and the arrangement of the plurality of strain gauges is improved, which can reduce the azimuth error and linearity difference of the force sensor and improve the accuracy of the output result. Specifically, a first groove surrounding and enclosing the sensing area is arranged on the load-bearing member, which can achieve a certain stress isolation effect. In some application scenarios, the load-bearing area of ​​the load-bearing member can be arranged outside the first groove arranged in an annular manner, and the sensing area is arranged inside the first groove. Therefore, the load-bearing area and the sensing area are separated by the first groove, so that when the load-bearing member is deformed by external force, due to the isolation effect of the first groove, the stress concentration transmitted from the load-bearing area to the sensing area is reduced, thereby reducing the deformation amplitude of the sensing area, thereby reducing the azimuth error and linearity difference, and improving the output accuracy of the force sensor. In addition, the strain gauges are arranged in the sensing area with intervals around the center of the sensing area, which can expand the stress sensing area of ​​multiple strain gauges, thereby expanding the signal acquisition area, and can measure and sense stresses in multiple different directions, reducing the measurement error; and the first side and the second side of each adjacent two strain gauges are arranged in an interlaced manner toward the center of the sensing area, which can improve the arrangement balance of multiple strain gauges in the sensing area, improve the measurement accuracy, and this arrangement method can cooperate with the first groove to reduce the influence of azimuth error and linear error on the output result, improve the accuracy of the output result, and improve the performance stability of the force sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0017] Figure 1 is a schematic diagram of the assembly structure of an embodiment of the force sensor of the present application;

[0018] Figure 2 is a schematic diagram of an exploded structure of an embodiment of a force sensor of the present application;

[0019] Figure 3 is a schematic diagram of an exploded structure of an embodiment of a force sensor of the present application;

[0020] Figure 4is a schematic cross-sectional structure diagram of an embodiment of a force sensor of the present application;

[0021] Figure 5 is a schematic diagram of a force state of an embodiment of a force sensor of the present application;

[0022] Figure 6 It is a structural schematic diagram of an embodiment of a load-bearing member of the present application;

[0023] Figure 7 It is a partial structural schematic diagram of an embodiment of the force sensor of the present application;

[0024] Figure 8 is a partial structural schematic diagram of another embodiment of the force sensor of the present application;

[0025] Fig. 9 It is a partial structural diagram of another embodiment of the force sensor of the present application. DETAILED DESCRIPTION

[0026] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present application. However, it should be clear to those skilled in the art that the present application may also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present application.

[0027] The terms "first", "second" and the like in this application are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. It should be understood that when used in this specification and the appended claims, the term "including" indicates the presence of the described features, wholes, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or their collections. It should also be understood that the terms used in this specification of the application are only for the purpose of describing a specific embodiment and are not intended to limit the application. As used in this specification of the application and the appended claims, unless the context clearly indicates otherwise, the singular forms of "one", "an" and "the" are intended to include plural forms. It should also be further understood that the term "and / or" used in this specification of the application and the appended claims refers to any combination of one or more of the items listed in association and all possible combinations, and includes these combinations.

[0028] It should be noted that when a certain element is fixed to another element, it includes directly fixing the element to the other element, or fixing the element to the other element through at least one other element in the middle. When an element is connected to another element, it includes directly connecting the element to the other element, or connecting the element to the other element through at least one other element in the middle.

[0029] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0030] A force sensor is a device that can convert the force applied to an object into an electrical signal. It can sense and measure the magnitude of the force by measuring the deformation or output voltage change caused by the force. A strain-type force sensor uses the deformation of a strain gauge to measure the magnitude of the force. The resistance value of the strain gauge will change with the force. By measuring the change in resistance value, the force applied to the object can be indirectly measured.

[0031] The smaller the orientation error and linearity difference, the more accurate the output result of the force sensor. For example, when the force sensor is used as a brake force sensor in a mechanical brake system, the linearity difference refers to the nonlinearity between the output signal of the force sensor and the displacement of the brake pedal, that is, the change between the output signal of the force sensor and the displacement of the brake pedal is not a strictly linear relationship; the smaller the linearity difference, the more linear the response of the force sensor to the displacement change of the brake pedal, and the better the performance of the force sensor. Conversely, the linearity difference will affect the accuracy of the force sensor output, which may cause the braking system to fail to accurately respond to the driver's operation, thereby affecting the braking performance and safety of the car; the orientation error usually refers to the offset of the force sensor relative to its ideal position. Improper installation or wear caused by long-term use can easily increase the orientation error of the force sensor. The orientation error will also affect the accuracy of the force sensor output because it can change the actual perception of the force sensor to the displacement of the brake pedal. For example, if the force sensor is offset, even if the brake pedal does not move, the force sensor may output an erroneous signal, resulting in misoperation of the brake system. Therefore, the detection and correction of the orientation error is a key step to ensure the correct response of the braking system.

[0032] In the prior art, force sensors are prone to large azimuth errors. Therefore, when the force applied to the force sensor deviates from the preset direction, the data error of the force sensor will vary greatly, resulting in low accuracy of the output result of the force sensor and poor performance stability of the force sensor.

[0033] This application first proposes a force sensor, such as Figures 1 to 9 The force sensor comprises a load-bearing member 100 and a plurality of strain gauges 200. The load-bearing member 100 comprises a sensing area 10. A first groove 11 is disposed on the load-bearing member 100. The first groove 11 surrounds and encloses the sensing area 10. Figures 7 to 9 Each strain gauge 200 includes a first side 210 and a second side 220 connected to each other, and the length of the first side 210 is greater than the length of the second side 220; wherein the strain gauges 200 are arranged in the sensing area 10 at intervals around the center of the sensing area 10, and the first side 210 and the second side 220 of each two adjacent strain gauges 200 are staggered toward the center of the sensing area 10.

[0034] When the force sensor of the present application is in use, the load-bearing member 100 is used to bear external force, and the load-bearing member 100 is deformed under the action of the external force. Since the strain gauge 200 is arranged on the sensing area 10 of the load-bearing member 100, when the load-bearing member 100 is deformed, the strain gauge 200 arranged on the load-bearing member 100 will also be deformed, thereby causing the resistance on the strain gauge 200 to change. The change in the resistance of the strain gauge 200 can be used to obtain a changed electrical signal, and the force on the load-bearing member 100 can be measured by using the electrical signal.

[0035] The force sensor of the present application is provided with a first groove 11 surrounding and enclosing the sensing area 10 on the load-bearing member 100, and the arrangement of the plurality of strain gauges 200 is improved, which can reduce the azimuth error and linearity difference of the force sensor and improve the accuracy of the output result. Specifically, the first groove 11 surrounding and enclosing the sensing area 10 is provided on the load-bearing member 100, which can achieve a certain stress isolation effect. In some application scenarios, the load-bearing area of ​​the load-bearing member 100 can be arranged outside the first groove 11 arranged in an annular manner, and the sensing area 10 is arranged inside the first groove 11. Therefore, the load-bearing area and the sensing area 10 are separated by the first groove 11. When the load-bearing member 100 is deformed by an external force, due to the isolation effect of the first groove 11, the stress concentration transmitted from the load-bearing area to the sensing area 10 is reduced, thereby reducing the deformation amplitude of the sensing area 10, thereby reducing the azimuth error and linearity difference, and improving the output accuracy of the force sensor. Furthermore, the strain gauges 200 are arranged in the sensing area 10 at intervals around the center of the sensing area 10, which can expand the stress sensing area of ​​the multiple strain gauges 200, thereby expanding the signal acquisition area, and can measure and sense stresses in multiple different directions, thereby reducing measurement errors; and the first side edges and the second side edges of each two adjacent strain gauges 200 are staggered toward the center of the sensing area 10, which can improve the arrangement balance of the multiple strain gauges 200 in the sensing area 10 and improve the measurement accuracy. Moreover, this arrangement method can cooperate with the first groove 11 to reduce the influence of the azimuth error and the linear error on the output result, thereby improving the accuracy of the output result and improving the performance stability of the force sensor.

[0036] For example, in an application scenario, Figure 3 As shown, the first groove 11 surrounds the sensing area 10 of the load-bearing member 100, and the first groove 11 can isolate stress and reduce the deformation amplitude of the sensing area 10; the multiple strain gauges 200 of the sensing area 10 are all rectangular strain gauges 200, and are arranged at intervals around the center of the sensing area 10, and the long sides and wide sides of two adjacent strain gauges 200 are staggered toward the center of the sensing area 10, which can cooperate with the first groove 11 to reduce the azimuth error and linearity difference of the load-bearing member 100.

[0037] In some embodiments, the load-bearing member 100 is an elastic member so that it can be deformed when subjected to external force.

[0038] In some embodiments, see Figures 4 to 6 The load-bearing member 100 includes a mounting end face 101 and a supporting end face 102 which are arranged opposite to each other. The sensing area 10 and the first groove 11 are both arranged on the mounting end face 101. The supporting end face 102 is provided with a second groove 12, and the first groove 11 and the second groove 12 are arranged in alignment. Specifically, in the first direction y (such as Figure 4As shown in FIG. 1 , the orthographic projections of the first groove 11 and the second groove 12 are completely overlapped, wherein the first direction y is perpendicular to the mounting end surface 101 and the supporting end surface 102.

[0039] By respectively arranging the first groove 11 and the second groove 12 on the relatively arranged mounting end surface 101 and the supporting end surface 102, the stress isolation effect can be further improved, the orientation error and linearity difference of the force sensor during use can be reduced, and the output accuracy can be improved.

[0040] In other embodiments (not shown), in the first direction y, the orthographic projections of the first groove 11 and the second groove 12 may also be arranged to be incompletely overlapped or spaced apart. Specifically, the width dimensions of the first groove 11 and the second groove 12 along the vertical y direction are different, so that in the first direction y, the orthographic projection of the first groove 11 and the second groove 12 with a smaller width dimension falls into the orthographic projection with a larger dimension. Alternatively, the first groove 11 and the second groove 12 are staggered in the first direction y, so that in the first direction y, the orthographic projections of the first groove 11 and the second groove 12 are spaced apart. In addition, the size of the first groove 11 or the second groove 12 may be adjusted according to the requirements for the stress isolation effect, and is not specifically limited.

[0041] In some embodiments, the first groove 11 or the second groove 12 is arranged in the form of a circular ring around the sensing area 10 to reduce the space occupied; in other embodiments (not shown), based on the product structure design requirements, the first groove 11 or the second groove 12 can be arranged in the form of a square ring or other ring-shaped form around the sensing area 10, without specific limitation.

[0042] In some embodiments, see Figures 3 to 6 The mounting end surface 101 is further provided with a first force-bearing area 21 and a third groove 13 ; the third groove 13 surrounds and encloses the first groove 11 , and the first force-bearing area 21 is located on the outer side of the third groove 13 facing away from the sensing area 10 .

[0043] Specifically, the external force is applied to the first force-bearing area 21 to achieve the effect of applying force to the load-bearing member 100. In an application scenario, such as Figure 5 , Figure 6 As shown, the external force applies a first pressure F1 to the load-bearing member 100 in the first force-bearing area 21 along the first direction y.

[0044] The beneficial effect of the above arrangement is that, since the third groove 13 surrounds and encloses the first groove 11, the first force-bearing area 21 is also located on the outside of the first groove 11 facing away from the sensing area 10, so the arrangement of the third groove 13 can isolate the first force-bearing area 21 from the first groove 11, and can isolate the first force-bearing area 21 from the sensing area 10; the first groove 11 can further increase the stress isolation effect on the first force-bearing area 21 and the sensing area 10; further, since the first groove 11 and the second groove 12 are aligned, the second groove 12 can also isolate the first force-bearing area 21 from the sensing area 10 to a certain extent, reducing the influence of the first force-bearing area 21 on the sensing area 10. Therefore, the above arrangement can improve the stress isolation effect, prevent stress concentration, reduce the deformation amplitude of the sensing area 10 under the action of external force, thereby reducing the orientation error and linearity difference, and improving the accuracy of the output.

[0045] In some embodiments, the specific shape of the third groove 13 is not limited, for example, it can be a circular ring or a square ring, etc., and similar modifications can be made with reference to the first groove 11 and the second groove 12.

[0046] In some embodiments, see Figures 4 to 6 The supporting end face 102 is provided with a second force-bearing area 22 and a fourth groove 14; the fourth groove 14 surrounds and encloses the second groove 12, and the second force-bearing area 22 is located between the second groove 12 and the fourth groove 14; along the positive projection direction of the mounting end face 101 toward the supporting end face 102, the projection of the first force-bearing area 21 is at least partially located outside the second force-bearing area 22.

[0047] The orthographic projection direction of the mounting end surface 101 toward the supporting end surface 102 is the first direction y, and the external force is applied to the second force-bearing area 22 to achieve the effect of applying force to the load-bearing member 100. In an application scenario, such as Figure 5 , Figure 6 As shown, the external force applies a second pressure F2 to the load-bearing member 100 in the second force-bearing area 22 along a direction opposite to the first direction y.

[0048] The first force-bearing area 21 is arranged on the mounting end surface 101, and the second force-bearing area 22 is arranged on the supporting end surface 102, so the first force-bearing area 21 and the second force-bearing area 22 are arranged opposite to each other, and the projection of the first force-bearing area 21 is arranged to be at least partially located outside the second force-bearing area 22, and the first pressure F1 and the second pressure F2 (such as Figure 5As shown in the figure, when the first pressure F1 and the second pressure F2 are in action, the action direction of the first pressure F1 and the action direction of the second pressure F2 can be parallel and arranged relative to each other, and the action line of the first pressure F1 and the action line of the second pressure F2 are not on the same straight line, so that the load-bearing member 100 can be deformed more obviously, thereby improving the sensitivity of the force sensor; further, the second groove 12 and the fourth groove 14 can isolate the second force-bearing area 22 from other areas, so as to facilitate stress isolation and force buffering, and because the second groove 12 is aligned with the first groove 11, the second groove 12 can isolate the second force-bearing area 22 from other areas. The effect of the force zone 22 and the sensing zone 10 reduces the influence of the second force zone 22 on the sensing zone 10; the second force zone 22 is arranged on the side of the fourth groove 14 facing the second groove 12, so that the projection of the first force zone 21 is at least partially located outside the second force zone 22. For example, in some application scenarios, the positive projection of the third groove 13 in the first direction y can also be arranged to surround and enclose the positive projection of the fourth groove 14. Since the first force zone 21 is located on the outer side of the third groove 13 facing away from the sensing zone 10, the projection of the first force zone 21 can be at least partially located outside the second force zone 22.

[0049] In some embodiments, Figures 4 to 6 As shown, the load-bearing member 100 includes a mounting end surface 101, and the sensing area 10 and the first groove 11 are both arranged on the mounting end surface 101; a mounting protrusion 15 surrounding and enclosing the first groove 11 is also convexly provided on the mounting end surface 101, and the mounting protrusion 15 is provided with a supporting step surface 151 on the inner side of the sensing area 10; the force sensor also includes a circuit board 300, and the circuit board 300 is electrically connected to the strain gauge 200; the circuit board 300 is located in the mounting protrusion 15 and supported on the supporting step surface 151.

[0050] In some application scenarios, such as Figure 4 As shown, the support step surface 151 is arranged in parallel with the mounting end surface 101 and is perpendicular to the first direction y, so that the circuit board 300 is arranged in parallel with the strain gauge 200 on the sensing area 10, thereby reducing the overall structural size; the circuit board 300 can output an electrical signal based on the resistance change of the strain gauge 200; the support step surface 151 is arranged on the mounting protrusion 15, which can not only fix the circuit board 300 and improve the position stability of the circuit board 300, but also allow an installation gap to exist between the circuit board 300 and the sensing area 10, thereby reducing the risk of the circuit board 300 being deformed together when the sensing area 10 is deformed, thereby reducing the risk of fatigue damage caused by frequent deformation of the circuit board 300, and improving the reliability of the circuit board 300.

[0051] In some embodiments, Figure 5 , 6As shown, the mounting protrusion 15 is provided with a support step on the inner side facing the sensing area 10, and the support step includes a support step surface 151 and a first abutting side surface 152. The circuit board 300 is supported on the support step surface 151, and the side wall of the circuit board 300 abuts against the first abutting side surface 152. The first abutting side surface 152 can limit and fix the circuit board 300. In some application scenarios, the first abutting side surface 152 can be arranged vertically to the support step surface 151.

[0052] In some embodiments, the mounting end surface 101 is further provided with a first force-bearing area 21 and a third groove 13 ; the third groove 13 surrounds and encloses the mounting protrusion 15 , and the first force-bearing area 21 is located on the outer side of the third groove 13 facing away from the mounting protrusion 15 .

[0053] The above arrangement can isolate the first stress-bearing area 21 from the mounting protrusion 15 through the third groove 13 , isolate stress and force buffering, reduce the influence of the external force of the first stress-bearing area 21 on the mounting protrusion 15 , and thus improve the position stability of the circuit board 300 .

[0054] In some embodiments, Figures 4 to 6 As shown, the support end surface 102 is provided with a second force-bearing area 22 and a fourth groove 14; the fourth groove 14 surrounds and encloses the second groove 12, and the second force-bearing area 22 is located between the second groove 12 and the fourth groove 14; along the orthographic projection direction of the mounting end surface 101 toward the support end surface 102, the projection of the first force-bearing area 21 is at least partially located outside the second force-bearing area 22; the orthographic projection of the mounting protrusion 15 in the first direction y is arranged to coincide with the orthographic projection of the fourth groove 14 in the first direction y. The above arrangement is convenient for reducing the overall size and improving the compactness of the structure.

[0055] In some embodiments, Figures 4 to 6 As shown, a fixed step is further provided on the outer side of the mounting protrusion 15 facing away from the sensing area 10; the force sensor also includes a housing 400, which is mounted on the mounting end surface 101, wherein an accommodating space for accommodating the circuit board 300 is formed between the housing 400 and the mounting end surface 101; the housing 400 includes a fixed side panel 401, and an end of the fixed side panel 401 is fixed to the fixed step.

[0056] The shell 400 can improve the waterproof and dustproof effect of the force sensor, reduce the risk of the circuit board 300 being disturbed by the external environment, and improve the performance stability of the force sensor; the setting of the fixed step is convenient for limiting the shell 400, and it is convenient to first limit the positioning of the shell 400 and then weld the shell 400 to the elastic part.

[0057] In some embodiments, Figures 4 to 6As shown, the fixed step includes a fixed step surface 153 and a second abutting side surface 154. The end of the fixed side plate 401 is supported on the fixed step surface 153, and the inner side wall of the fixed side plate 401 abuts against the second abutting side surface 154. The second abutting side surface 154 can limit and fix the fixed side plate 401. In some application scenarios, the second abutting side surface 154 can be arranged perpendicular to the fixed step surface 153.

[0058] In some embodiments, the load-bearing member 100 is further provided with a mounting hole 103, and the sensing area 10 surrounds the mounting hole 103; the outer shell 400 includes a top plate 402 and a mounting column 403 connected to the top plate 402, and the fixed side plate 401 is formed by extending from the periphery of the top plate 402, and the mounting column 403 and the fixed side plate 401 are located on the same side of the top plate 402; wherein the mounting column 403 is installed in the mounting hole 103, and a sealing ring 500 is also provided between the side wall of the mounting column 403 and the inner wall of the mounting hole 103.

[0059] The above-mentioned arrangement makes it easy for the strain gauge 200 in the sensing area 10 to sense the deformation of the load-bearing member 100 from all directions, thereby reducing the linearity difference and improving the output accuracy of the force sensor; by arranging the top plate 402 and the mounting column 403, not only can the waterproof and dustproof performance and the sealing effect of the accommodating space for the circuit board 300 be improved, but also the outer shell 400 can be fixed to improve the stability of the overall structure.

[0060] In some embodiments, Figure 5 , Figure 6 As shown, the inner wall of the mounting hole 103 forms a mounting groove 16 which can be used to fix the limiting sealing ring 500 .

[0061] In some embodiments, Figure 5 As shown, the side wall of the mounting column 403 is spaced apart from the inner wall of the mounting hole 103 , and the sealing ring 500 is sealed with the side wall of the mounting column 403 on one side and sealed with the inner wall of the mounting hole 103 on the other side.

[0062] The above arrangement can reduce the interference of the housing 400 on the deformation of the load-bearing member 100 under the action of force, and can provide an avoidance space for the deformation of the load-bearing member 100, thereby improving the performance stability and output accuracy of the force sensor.

[0063] In some embodiments, the circuit board 300 may be configured as an annular circuit board 300 , and the mounting post 403 passes through the ring portion of the annular circuit board 300 to be disposed in the mounting hole 103 .

[0064] In some embodiments, see Figures 7 to 9, each strain gauge 200 is rectangular; the strain gauges 200 are arranged in a circle with the first side 210 and the second side 220 staggered toward the center of the sensing area 10 and evenly spaced around the center of the sensing area 10.

[0065] The first side 210 is the long side of the rectangle, the second side 220 is the wide side of the rectangle, and the multiple strain gauges 200 are arranged in a circular pattern with uniform spacing, which means that the central angles of the spacings between two adjacent strain gauges 200 are equal. This arrangement enables the strain gauges 200 to detect the deformation of the load-bearing member 100 from all directions, thereby being able to more accurately sense the stress of the load-bearing member 100, thereby being able to improve the accuracy of the output result of the force sensor.

[0066] In some embodiments, Figures 7 to 9 As shown, 4, 6 or 8 strain gauges 200 may be provided so as to be evenly spaced in a circular arrangement around the center of the sensing area 10 to improve the accuracy of the measurement sensing and thus improve the accuracy of the output result of the force sensor. Of course, other numbers of strain gauges 200 may be provided in other embodiments, which are not limited here.

[0067] In other embodiments, the strain gauge 200 may also be in other shapes such as a parallelogram having first sides 210 and second sides 220 of different lengths and connected to each other.

[0068] In other embodiments, the plurality of strain gauges 200 are arranged in a circle around the center of the sensing area 10 , and the central angles of the intervals between two adjacent strain gauges 200 may be different.

[0069] In other embodiments, similar improvements may be made to the force sensor, which will not be described in detail here.

[0070] The present application further proposes an electronic mechanical braking system, which includes the above-mentioned force sensor.

[0071] The specific implementation and working principle of the force sensor can be found in the above embodiments and will not be described in detail here.

[0072] In one application scenario, the force sensor can be used as a brake force sensor in an electronic mechanical braking system, which can improve the accuracy of the electronic mechanical braking system's perception of the braking force, improve the electronic mechanical braking system's ability to correctly respond to the user's braking operation, and improve the reliability of the system.

[0073] The present application further proposes a car, which includes the above-mentioned electromechanical braking system.

[0074] The specific implementation and working principle of the electronic mechanical braking system can be found in the above embodiments and will not be described in detail here.

[0075] Using the above-mentioned electromechanical braking system in a car can improve the accuracy of the car's perception of the user's braking operation, thereby improving the car's safety and the user's experience.

[0076] Different from the prior art, the force sensor of the present application includes a load-bearing member and a plurality of strain gauges. The load-bearing member includes a sensing area. A first groove is provided on the load-bearing member, and the first groove surrounds and encloses the sensing area. Each strain gauge includes a first side and a second side connected to each other, and the length of the first side is greater than the length of the second side. The strain gauges are arranged in the sensing area in an interval arrangement around the center of the sensing area, and the first side and the second side of each two adjacent strain gauges are arranged in an alternating manner toward the center of the sensing area. The first groove surrounding and enclosing the sensing area is provided on the load-bearing member, and the arrangement of the plurality of strain gauges is improved, which can reduce the orientation error and linearity difference of the force sensor and improve the accuracy of the output result. Specifically, a first groove surrounding and enclosing the sensing area is arranged on the load-bearing member, which can achieve a certain stress isolation effect. In some application scenarios, the load-bearing area of ​​the load-bearing member can be arranged outside the first groove arranged in an annular manner, and the sensing area is arranged inside the first groove. Therefore, the load-bearing area and the sensing area are separated by the first groove, so that when the load-bearing member is deformed by external force, due to the isolation effect of the first groove, the stress concentration transmitted from the load-bearing area to the sensing area is reduced, thereby reducing the deformation amplitude of the sensing area, thereby reducing the azimuth error and linearity difference, and improving the output accuracy of the force sensor. In addition, the strain gauges are arranged in the sensing area with intervals around the center of the sensing area, which can expand the stress sensing area of ​​multiple strain gauges, thereby expanding the signal acquisition area, and can measure and sense stresses in multiple different directions, reducing the measurement error; and the first side and the second side of each adjacent two strain gauges are arranged in an interlaced manner toward the center of the sensing area, which can improve the arrangement balance of multiple strain gauges in the sensing area, improve the measurement accuracy, and this arrangement method can cooperate with the first groove to reduce the influence of azimuth error and linear error on the output result, improve the accuracy of the output result, and improve the performance stability of the force sensor.

[0077] It is worth noting that the drawings in this article are only intended to illustrate the structural relationship and connection relationship of the product of the present application, and do not limit the specific structural dimensions of the product of the present application.

[0078] The above description is only an implementation method of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A force sensor, characterized in that: include: A load-bearing member, the load-bearing member includes a sensing area, and a first groove is provided on the load-bearing member, and the first groove surrounds and encloses the sensing area; A plurality of strain gauges, each of the strain gauges comprises a first side and a second side connected to each other, the length of the first side is greater than the length of the second side; wherein, The strain gauges are arranged in the sensing area in an interval around the center of the sensing area, and the first side edges and the second side edges of every two adjacent strain gauges are staggered and arranged toward the center of the sensing area; Wherein, the load-bearing member comprises a mounting end surface, and the sensing area and the first groove are both arranged on the mounting end surface; The mounting end surface is also provided with a mounting protrusion surrounding and enclosing the first groove, and the mounting protrusion is provided with a supporting step surface on the inner side facing the sensing area; The force sensor further includes a circuit board, and the circuit board is electrically connected to the strain gauge; The circuit board is located in the mounting protrusion and supported on the supporting step surface; Wherein, the mounting end surface is also provided with a first force-bearing area and a third groove; The third groove surrounds and encloses the mounting protrusion, and the first force-bearing area is located on the outer side of the third groove facing away from the mounting protrusion; Wherein, the load-bearing member comprises the mounting end surface and the supporting end surface which are arranged opposite to each other, the supporting end surface is provided with a second groove, and the first groove and the second groove are arranged in alignment; The third groove surrounds and encloses the first groove, and the first force-bearing area is located on the outer side of the third groove facing away from the sensing area; Wherein, the supporting end surface is provided with a second force-bearing area and a fourth groove; The fourth groove surrounds and encloses the second groove, and the second force-bearing area is located between the second groove and the fourth groove; Along the orthographic projection direction of the mounting end surface toward the supporting end surface, the projection of the first force-bearing area is at least partially located outside the second force-bearing area.

2. The force sensor according to claim 1, characterized in that The outer side of the mounting protrusion facing away from the sensing area is also provided with a fixed step; The force sensor further comprises a housing, wherein the housing is mounted on the mounting end surface, wherein an accommodating space for accommodating the circuit board is formed between the housing and the mounting end surface; The housing includes a fixed side plate, and an end portion of the fixed side plate is fixed to the fixed step.

3. The force sensor according to claim 2, characterized in that The load-bearing member is also provided with a mounting hole, and the sensing area surrounds the mounting hole; The housing includes a top plate and a mounting column connected to the top plate, the fixed side plate is formed by extending from the periphery of the top plate, and the mounting column and the fixed side plate are located on the same side of the top plate; wherein, The mounting post is mounted in the mounting hole, and a sealing ring is provided between the side wall of the mounting post and the inner wall of the mounting hole.

4. The force sensor according to any one of claims 1 to 3, characterized in that: Each of the strain gauges is rectangular; The strain gauges are arranged in a circle with the first side and the second side alternately facing the center of the sensing area and surrounding the center of the sensing area at even intervals.

5. An electromechanical braking system, characterized in that: The electromechanical braking system comprises a force sensor as claimed in any one of claims 1 to 4.

6. A car, characterized in that: The automobile comprises the electromechanical braking system of claim 5 .

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