A force measuring mechanism

Abstract

The present invention relates to the field of sensor technology, specifically a force measurement mechanism, including a bottom plate, characterized in that a base is fixedly connected to the upper side of the bottom plate, a linear motor is fixedly connected to the base, a fixed plate is fixedly connected to the bottom plate, a first sliding groove is provided on the fixed plate, the first sliding groove is connected to a first guide plate through a sliding device, and a first sliding plate is fixedly connected to the first guide plate. The present invention first controls the linear motor output shaft through a controller to push the second sliding plate to move, thereby causing one end of the contact rod to approach the workpiece at high speed, and then slowly contact the workpiece. When the position remains unchanged and the current increases, it indicates that the workpiece has been contacted, and then the force value F is calculated by F=Fm-Fr-Fa. In applications such as spring and key force curve measurement, the device actively extends the contact rod to measure the force of workpieces such as springs and keys at different depths.

Description

Technical Field

[0001] The present invention relates to the field of sensor technology, and in particular to an active non-deformable force measurement method and a mechanism thereof. Background Art

[0002] A sensor is a detection device that can sense the information being measured and convert the sensed information into electrical signals or other required forms of information output according to certain rules to meet the requirements of information transmission, processing, storage, display, recording and control.

[0003] The sensor includes a force sensor, which is an electronic component that converts force signals into electrical signals for output.

[0004] However, most of the force sensors on the market currently convert the electrical signals generated by material strain into force values. This measurement method has the following shortcomings: 1. The material is deformed back and forth under long-term force, is prone to fatigue, and has a limited lifespan; 2. In applications where both force and position accuracy are required, the material is relatively soft and deforms after being subjected to force, making it impossible to ensure accurate position; 3. The force sensor itself is not strong enough and is damaged when it receives unexpected overload force, bending moment, and other external forces; 4. When the measuring head equipped with the force sensor approaches the workpiece for force measurement, the force generated by the acceleration and deceleration of the measuring head, the friction of the guide rail, etc., will also act on the force sensor due to its mass, resulting in inaccurate data. Summary of the invention

[0005] The object of the present invention is to provide an active non-deformation force measurement method and mechanism thereof to solve the problems raised in the above background technology.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] An active non-deformable force measurement method and mechanism thereof include a base plate, characterized in that a base is fixedly connected to the upper side of the base plate, a linear motor is fixedly connected to the base, a fixed plate is fixedly connected to the base plate, a first sliding groove is provided on the fixed plate, the first sliding groove is connected to a first guide plate through a sliding device, a first sliding plate is fixedly connected to the first guide plate, a second sliding groove is provided on the first sliding plate, the second sliding groove is also connected to a second guide plate through a sliding device, a second sliding plate is fixedly connected to the second guide plate, the output shaft of the linear motor is fixedly connected to the side wall of the second sliding plate, a fixed block is fixedly connected to the upper side of the second sliding plate, a contact rod is fixedly connected to the side wall of the fixed block, a measuring device passes through the upper side of the base plate, and a controller is fixedly connected to the upper side of the base plate.

[0008] As a further improvement of the present technical solution: the sliding device includes two fixed rods, the two fixed rods are fixedly connected in the first sliding groove and the second sliding groove, the first guide plate and the second guide plate are each provided with two through grooves matching the fixed rods, each of the fixed rods is slidably connected in the through groove, a plurality of spherical grooves are provided on the upper side of each of the through grooves, and a ball is provided in each of the spherical grooves.

[0009] As a further improvement of the technical solution: the measuring device includes a code reader, a sliding rod is fixedly connected to the side wall of the code reader, a scale is provided on the side wall of the second sliding plate, and the sliding rod is slidably connected to the upper side of the scale.

[0010] As a further improvement of the technical solution: a warning sign is provided on the side wall of the base, and fluorescent powder is provided on the warning sign.

[0011] As a further improvement of the technical solution: the linear motor is provided with an anti-oxidation coating, and the anti-oxidation coating is evenly sprayed on the surface of the linear motor.

[0012] As a further improvement of the technical solution: it is characterized in that a Teflon coating is provided on the surface of each of the fixing rods, and the thickness of the Teflon coating is 15 μm.

[0013] As a further improvement of the technical solution: one end of the contact rod is arranged in an elliptical shape.

[0014] As a further improvement of the technical solution: the linear motor is a linear micro motor of model BM202.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] First, the controller controls the linear motor output shaft to push the second sliding plate to move, so that one end of the contact rod approaches the workpiece at high speed, and then slowly contacts the workpiece. When the position remains unchanged and the current increases, it means that the workpiece has been contacted. Then the force value F is calculated by F=Fm-Fr-Fa. Compared with the existing technology, most of the force sensors on the market currently convert the electrical signal generated by material strain into force value. This measurement method has the following shortcomings: 1. The material is deformed back and forth under long-term force, is prone to fatigue, and has a limited lifespan; 2. In applications where both force and position need to be accurate at the same time, the material is relatively soft and deforms after being stressed, and the position cannot be guaranteed to be accurate; 3. The strength of the force sensor itself is not high, and it is damaged when it receives unexpected overload force, bending moment and other external forces; 4. When the measuring head equipped with the force sensor approaches the workpiece for force measurement, because the measuring head has mass, the force generated by the acceleration and deceleration of the measuring head, the friction of the guide rail, etc. will also act on the force sensor, resulting in inaccurate data. In applications such as spring and button force curve measurement, the device actively By extending the contact rod, the force of workpieces such as springs and buttons at different depths can be measured. Since the device has both the functions of a code reader and a force measurement, it can also measure the position and force curves within a certain stroke, which is very convenient to use. Compared with traditional force sensors based on material deformation, this device can withstand external forces and bending moments in various directions under the same range, and has stronger impact resistance under the same accuracy index. This device supports dynamic measurement because it takes into account the force caused by the acceleration of the moving part. Traditional sensors are mostly used for static measurement. During dynamic measurement, it is necessary to additionally calculate the force of the moving workpiece when it is accelerated or decelerated, which makes it more difficult to use. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the top view of the active non-deformable force measurement method and its mechanism proposed by the present invention;

[0018] Figure 2 The active non-deformation force measurement method and the side cross-sectional structure diagram between the fixed plate, the first sliding plate and the second sliding plate in the mechanism thereof proposed by the present invention;

[0019] Figure 3 This is a schematic diagram of the structure between the second sliding plate 6 and the second guide plate in the active non-deformation force measurement method and the mechanism proposed by the present invention;

[0020] Figure 4 for Figure 2 A is a schematic diagram of the partially enlarged structure of the middle part;

[0021] Figure 5 This is a side structural schematic diagram of the active non-deformation force measurement method and its mechanism proposed by the present invention.

[0022] In the figure: 1 base, 2 bottom plate, 3 linear motor, 4 fixed plate, 5 first sliding plate, 6 second sliding plate, 7 fixed block, 8 contact rod, 9 slide bar, 10 encoding reader, 11 ruler, 12 controller, 13 fixed rod, 14 first guide plate, 15 second guide plate, 16 first sliding groove, 17 second sliding groove, 18 through groove, 19 ball, 20 warning sign. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] See also Figures 1 to 5 In an embodiment of the present invention, an active non-deformable force measurement method and mechanism thereof include a bottom plate 2, a base 1 is fixedly connected to the upper side of the bottom plate 2, a linear motor 3 is fixedly connected to the base 1, a fixed plate 4 is fixedly connected to the bottom plate 2, a first sliding groove 16 is provided on the fixed plate 4, the first sliding groove 16 is connected to the first guide plate 14 through a sliding device, a first sliding plate 5 is fixedly connected to the first guide plate 14, a second sliding groove 17 is provided on the first sliding plate 5, the second sliding groove 17 is also connected to the second guide plate 15 through a sliding device, a second sliding plate 6 is fixedly connected to the second guide plate 15, an output shaft of the linear motor 3 is fixedly connected to the side wall of the second sliding plate 6, a fixed block 7 is fixedly connected to the upper side of the second sliding plate 6, a contact rod 8 is fixedly connected to the side wall of the fixed block 7, a measuring device is passed through the upper side of the bottom plate 2, a controller 12 is fixedly connected to the upper side of the bottom plate 2, and the linear motor 3 is electrically connected to the controller 12.

[0025] See also Figure 2 and Figure 4The sliding device includes two fixed rods 13, and the two fixed rods 13 are fixedly connected in the first sliding groove 16 and the second sliding groove 17. The first guide plate 14 and the second guide plate 15 are each provided with two through grooves 18 matching the fixed rod 13, each fixed rod 13 is slidably connected in the through groove 18, and a plurality of spherical grooves are provided on the upper side of each through groove 18, and a ball 19 is provided in each spherical groove. The first guide plate 14 and the second guide plate 15 are both rollingly connected to the fixed rod 13 through a plurality of ball bearings 19, so that the contact area is greatly reduced, and the friction resistance when the first guide plate 14 and the second guide plate 15 slide can be reduced to a greater extent. When the output shaft of the linear motor 3 is extended, the second sliding plate 6 will be pushed to move to the right side. The second guide plate 15 on the bottom side of the second sliding plate 6 is located in the first sliding plate 5. When the second guide plate 15 slides to the right side wall of the second sliding groove 17, it will drive the first sliding plate 5 to move to the right side together, thereby making the extension distance of the contact rod 8 farther.

[0026] See also Figure 1 The measuring device includes a code reader 10, a slide bar 9 is fixedly connected to the side wall of the code reader 10, and a scale 11 is on the side wall of the second sliding plate 6. The slide bar 9 is slidably connected to the upper side of the scale 11. When the second sliding plate 6 moves, the scale 11 on the side wall can be driven to move. The code reader 10 can calculate the gravity acceleration a when the linear motor 3 drives the second sliding plate 6 to move by reading the distance moved by the slide bar 9 on the scale 11 per unit time.

[0027] See also Figure 1 A warning sign 20 is provided on the side wall of the base 1, and fluorescent powder is provided on the warning sign 20. The warning sign 20 can be used to remind non-professionals not to disassemble the device during the day or at night to prevent non-professionals from fiddling with the device and causing damage to the device.

[0028] See also Figure 1 The linear motor 3 is provided with an anti-oxidation coating, which is evenly sprayed on the surface of the linear motor 3. The anti-oxidation coating is a galvanized coating, which can slow down the oxidation rate of ungalvanized materials by twenty times, thereby greatly reducing the oxidation corrosion of the device by air and extending the service life of the device.

[0029] See also Figure 1 A Teflon coating is provided on the surface of each fixed rod 13, and the thickness of the Teflon coating is 15 μm. The surface of the fixed rod 13 adopts a Teflon surface structure to reduce the surface friction coefficient of the fixed rod 13, so that the ball 19 rolls on the fixed rod 13 more smoothly, greatly reducing the friction resistance.

[0030] See also Figure 1 One end of the contact rod 8 is elliptical, and the elliptical end is a contact point, so that the contact point is more convenient to apply force when measuring the measured object.

[0031] See also Figure 1 The linear motor 3 is a linear micro motor of model BM202, which has the advantages of fast acceleration, short positioning time, good dynamic performance, and is easier to control.

[0032] The working principle of the present invention is:

[0033] The force of the linear motor 3 is controlled by the controller 12 by controlling the magnitude of the current, but part of the current is used to overcome the friction of the sliding device, part of it is used to overcome the gravity of the moving part of the workpiece, overcome the force of acceleration and deceleration of the moving part of the workpiece, the force of the contact point contacting the external workpiece, etc. The force of the motor is Fm, the gravity of the device composition is Fa, the part that overcomes the resistance is Fr, and the contact force is F, then F=Fm-Fr-Fa, the controller 12 can obtain the real-time current value of the linear motor 3, and the force Fm can be calculated by knowing the constant Kf (N / A) of the linear motor 3; gravity Fa=M (mass of the moving part)*a (gravitational acceleration), where M is the mass of the device, which can be measured, a can be obtained through the change of the encoder reader 10, Fr is the guide rail resistance, and Fr can be easily measured through the friction formula Fr=μ*Fn.

[0034] First, the controller 12 controls the output shaft of the linear motor 3 to push the second sliding plate 6 to move, so that one end of the contact rod 8 approaches the workpiece at high speed, and then slowly contacts the workpiece. When the position remains unchanged and the current increases, it means that the workpiece has been contacted. Then the force value F is calculated by F=Fm-Fr-Fa. In applications such as spring and button force curve measurement, the device actively extends the contact rod 8 to measure the force of springs, buttons and other workpieces at different depths. Since the device has the functions of a coding reader 10 and a force measurement, it can also measure the position and force curves within a certain stroke, which is very convenient to use. Compared with traditional force sensors based on material deformation, under the same range, this device can withstand external forces and bending moments in various directions, and has stronger impact resistance under the same accuracy index. Since this device takes into account the force caused by the acceleration of the moving part, it supports dynamic measurement. Traditional sensors are mostly used for static measurement. Because dynamic measurement requires additional calculation of the force of the moving workpiece when it is accelerated or decelerated, it is difficult to use.

[0035] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A force measuring mechanism, comprising a base plate (2), characterized in that: The upper side of the bottom plate (2) is fixedly connected to a base (1), the base (1) is fixedly connected to a linear motor (3), the bottom plate (2) is fixedly connected to a fixed plate (4), the fixed plate (4) is provided with a first sliding groove (16), the first sliding groove (16) is connected to a first guide plate (14) via a sliding device, the first guide plate (14) is fixedly connected to a first sliding plate (5), the first sliding plate (5) is provided with a second sliding groove (17), the second sliding groove (17) is also connected to a first guide plate (14) via a sliding device. The sliding device is connected to a second guide plate (15), a second sliding plate (6) is fixedly connected to the second guide plate (15), an output shaft of the linear motor (3) is fixedly connected to a side wall of the second sliding plate (6), a fixed block (7) is fixedly connected to the upper side of the second sliding plate (6), a contact rod (8) is fixedly connected to the side wall of the fixed block (7), and one end of the contact rod (8) is elliptical; a measuring device passes through the upper side of the base plate (2), and a controller (12) is fixedly connected to the upper side of the base plate (2); The sliding device comprises two fixed rods (13), the two fixed rods (13) are fixedly connected in a first sliding groove (16) and a second sliding groove (17), the first guide plate (14) and the second guide plate (15) are each provided with two through grooves (18) matching the fixed rods (13), each of the fixed rods (13) is slidably connected in the through groove (18), a plurality of spherical grooves are provided on the upper side of each of the through grooves (18), and a ball (19) is provided in each of the spherical grooves; The measuring device comprises a code reader (10), a slide bar (9) is fixedly connected to a side wall of the code reader (10), a scale (11) is provided on the side wall of the second sliding plate (6), and the slide bar (9) is slidably connected to the upper side of the scale (11); The output shaft of the linear motor (3) is controlled by a controller (12) to push the second sliding plate (6) to move, thereby causing one end of the contact rod (8) to approach the workpiece at high speed and then slowly contact the workpiece. When the position remains unchanged and the current increases, it indicates that the workpiece has been contacted. Then, the force value F is calculated by F=Fm-Fr-Fa; the force of the motor is Fm, the gravity of the device composition is Fa, the part that overcomes the resistance is Fr, and the contact force is F.

2. A force measuring mechanism according to claim 1, characterized in that: A warning sign (20) is provided on the side wall of the base (1), and fluorescent powder is provided on the warning sign (20).

3. A force measuring mechanism according to claim 2, characterized in that: The linear motor (3) is provided with an anti-oxidation coating, and the anti-oxidation coating is evenly sprayed on the surface of the linear motor (3).

4. A force measuring mechanism according to claim 3, characterized in that: A Teflon coating is provided on the surface of each fixing rod (13), and the thickness of the Teflon coating is 15 μm.

5. A force measuring mechanism according to any one of claims 1 to 4, characterized in that: The linear motor (3) is a linear micro motor of model BM202.

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