An inspection station and method for inspecting vehicle tyres
By setting up three uniaxial force sensors on the inspection bench and using coupling guide rods and connecting rods to achieve crosstalk compensation, the measurement error problem caused by force sensor crosstalk in the prior art is solved, and high precision and reliability of vehicle tire low-speed uniformity detection are achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- ZF FRIEDRICHSHAFEN AG
- Filing Date
- 2020-10-20
- Publication Date
- 2026-06-19
AI Technical Summary
The existing vehicle tire low-speed uniformity testing bench has undefined crosstalk between force sensors, which leads to measurement errors and makes accurate calibration difficult.
An inspection table with three uniaxial force sensors is used. The first and second force sensors are used to detect radial force, and the third force sensor is used to detect lateral force. Targeted crosstalk between the force sensors is achieved through coupling guide rods and coupling connecting rods to compensate for temperature effects and improve measurement accuracy.
It enables accurate detection of radial and lateral forces, reduces the impact of temperature changes on measurement results, eliminates undefined crosstalk between multi-axial force sensors, and improves the measurement accuracy and calibration reliability of the inspection station.
Smart Images
Figure CN114556073B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to an inspection bench for inspecting vehicle tires and a method for inspecting vehicle tires. Background Technology
[0002] In the prior art, a so-called "Low Speed Uniformity" test bench for determining the synchronous running characteristics of vehicle tires is known. The synchronous running characteristics in low speed uniformity measurement primarily involve detecting and evaluating forces when the vehicle tire is rolling relatively slowly (e.g., at approximately 60 tire revolutions per minute). For the vehicle tire under test, the test bench typically has two biaxially configured force sensors that can detect forces along two separate spatial directions. This can lead to undefined crosstalk between the two force detection channels assigned to different spatial directions.
[0003] A wheel force gauge for measuring tire forces is known from DE 102 60 000 B4, wherein a wheel can be secured to an axle, which is supported in a hollow shaft via rolling bearings. The hollow shaft is hydrostatically supported in a housing fixed relative to a frame. The wheel force gauge includes at least two uniaxial force sensors assigned to the axle, wherein a first force sensor is configured to detect the wheel load component, and a second force sensor is configured to detect the tangential force component. These force sensors are not coupled to each other.
[0004] When measuring tire force using a known test bench, measurement errors may occur due to the type of test bench structure. Summary of the Invention
[0005] The objective of this invention is to provide an improved inspection bench for inspecting vehicle tires.
[0006] According to the present invention, this task is solved by an inspection bench for inspecting vehicle tires according to the present invention.
[0007] This invention relates to an inspection bench for inspecting vehicle tires, comprising a drum on a drum shaft and force sensors for detecting radial and lateral forces acting on the drum shaft. The inspection bench according to the invention is characterized in that it comprises three uniaxial force sensors, wherein first and second force sensors are arranged to detect radial forces, wherein a third force sensor is arranged to detect lateral forces, and wherein the first and third force sensors are coupled.
[0008] According to the present invention, an inspection table for inspecting vehicle tires is provided, comprising a drum arranged on a drum shaft. The drum represents the rolling surface of the vehicle tire to be inspected. Radial and lateral forces acting between the drum and the vehicle tire are detected by means of three force sensors on the inspection table. The three force sensors are three uniaxial force sensors, i.e., force sensors configured to detect forces only along a single spatial direction. An advantage obtained from this, for example, is that each force sensor can be calibrated individually. The force sensors can, for example, be force sensors operating based on the piezoelectric principle. Two of the force sensors, namely the first and second force sensors, are arranged on the inspection table or in contact with the drum shaft in such a way that they can detect radial forces acting on the drum shaft. The third force sensor is arranged on the inspection table or in contact with the drum shaft in such a way that it can detect lateral forces acting on the drum shaft. Furthermore, the first force sensor capable of detecting radial forces and the third force sensor capable of detecting lateral forces are coupled to each other, such that when a force acts on one of the two force sensors, targeted crosstalk occurs to the corresponding other force sensor. Therefore, when a radial force, primarily detected by the first force sensor, occurs, crosstalk exists to the third force sensor, causing it to also detect the force. Conversely, when a lateral force, detected by the third force sensor, occurs, crosstalk exists to the first force sensor, causing it to also detect the force.
[0009] The advantage of this is that the detected force can be determined very accurately using only three force sensors. This is because the coupling between the first and third force sensors, and the crosstalk thus selectively adjusted, provides additional information about the force detected by either the first or third force sensor. This is particularly advantageous for detecting radial forces (which are detected equally by the first and second force sensors). The additional information obtained through selectively adjusted crosstalk can, for example, be used to calculate the effect of temperature on the measurement data of the first force sensor. In contrast, in the prior art, although crosstalk often exists between force sensors targeting different force directions or between different force detection directions of multi-axis force sensors, this effect is undesirable because it is not specifically implemented and therefore does not provide usable information. However, the test bench according to the invention allows for the most accurate calibration possible for each force sensor, and calibrates the crosstalk from the first force sensor to the third force sensor, and vice versa.
[0010] Because only a single force sensor, or a third force sensor, is used to detect lateral force, the influence of temperature changes on the measurement results of lateral force can be advantageously and completely eliminated.
[0011] Preferably, a first force sensor is assigned to or in contact with a first axial end of the drum shaft, and a second force sensor is assigned to or in contact with a second axial end of the drum shaft. Therefore, radial forces acting on the drum can be received and detected particularly reliably. Radial forces typically occur when the vehicle tire to be tested is loaded with a preset force and contacts the drum in the radial direction, i.e., using radial force.
[0012] According to a preferred embodiment of the invention, a first force sensor is contacted with a first axial end of the drum shaft via a first coupling guide (Koppelungslenker), and a second force sensor is contacted with a second axial end of the drum shaft via a second coupling guide. This enables the radial force acting on the drum shaft to be optimally introduced into the first and second force sensors. The preferred, substantially flattened cubic construction of the coupling guides also allows for the detection of torque based on radial forces acting at different locations on the drum shaft.
[0013] According to a particularly preferred embodiment of the invention, a first coupling guide rod is configured to contact a first axial end of the drum shaft via a detachable threaded connection, and a second coupling guide rod is configured to contact a second axial end of the drum shaft via a detachable threaded connection. The advantage of this is that both the first and second coupling guide rods can be easily detached from their respective axial ends for, for example, replacement or substitution, or to alter the structure of the inspection table. Nevertheless, the threaded connection still ensures reliable retention of the first or second coupling guide rod at its first or second axial end. Furthermore, this avoids the lag that often occurs in the prior art, as the threaded connection is backlash-free.
[0014] According to another preferred embodiment of the invention, a third force sensor is arranged to contact the first axial end of the drum shaft via a coupling link. The advantage of this is that although the third force sensor can be flexibly arranged at a preset distance from the drum shaft, it still contacts the drum shaft, thus enabling it to detect lateral forces acting on the drum shaft.
[0015] Preferably, the coupling link is arranged coaxially with the drum shaft on the first axial end of the drum shaft. This arrangement enables the lateral force acting on the drum shaft to be transmitted to the third force sensor in the most optimized way possible.
[0016] According to another particularly preferred embodiment of the invention, the third force sensor is in contact with the first coupling guide via a coupling link. The advantage of this is that targeted crosstalk from the output force sensor to the third force sensor can be adjusted via the coupling link and the coupling guide, and vice versa.
[0017] Preferably, the coupling guide rod has an opening through which the coupling link is guided with as little clearance as possible. Therefore, the coupling link can contact the first axial end on one side and the coupling guide rod on the other side without clearance, and thus without any hysteresis effect.
[0018] According to another particularly preferred embodiment of the invention, the inspection table is configured to adjust the crosstalk of the radial force on the third force sensor by means of a preset length and / or preset stiffness of the coupling link. The advantage of this is that the manifestation of crosstalk from the first force sensor to the third force sensor and vice versa can be adjusted specifically and as needed. Here, the shorter and more rigid the coupling link, the more pronounced the crosstalk from the first force sensor to the third force sensor and vice versa.
[0019] Preferably, the defined crosstalk is further adjusted by the preset length and / or preset stiffness of the first coupling guide.
[0020] According to another preferred embodiment of the invention, the inspection table is configured to adjust the sturz of the drum using first and / or second coupling guides of varying lengths. Therefore, the sturz of the drum shaft relative to the axis of rotation of the tire being inspected can be easily adjusted via the lengths of the coupling guides, particularly the different lengths of the first and second coupling guides. The advantage of this is that the wheel being inspected can be subjected to various inspection scenarios in a simple manner.
[0021] According to another preferred embodiment of the invention, the inspection table is configured to adjust the tilt direction of the drum by means of the misalignment of the first and / or second force sensors. The advantage of this is that the tilt direction of the drum shaft relative to the axis of rotation of the vehicle tire being inspected can be adjusted in a simple manner.
[0022] The present invention also relates to a method for inspecting vehicle tires, wherein radial force and lateral force acting on the drum shaft of a rotating drum are detected by means of force sensors. The method according to the invention is characterized in that the radial force is detected by means of first and second force sensors of a single axis, wherein the lateral force is detected by means of a third force sensor of a single axis, and wherein crosstalk between the radial force and the third force sensor is adjusted. The method according to the invention thus describes the inspection of vehicle tires in an inspection bench according to the invention, which leads to the advantages already described.
[0023] According to a preferred embodiment of the invention, the first force sensor and / or the second force sensor and / or the third force sensor are individually calibrated. The advantage of this is that, for example, temperature changes in the testing environment (which also affect the third force sensor) do not cause any changes in the test results of the force sensors. Attached Figure Description
[0024] The invention is now described by way of example with reference to the embodiments shown in the accompanying drawings. Wherein:
[0025] Figure 1 Exemplary and schematic illustrations show possible implementations of the inspection table according to the present invention.
[0026] Figure 2 Possible implementations of the coupling guide are illustrated exemplaryly and schematically, and
[0027] Figure 3 The drum shaft of the inspection table according to the present invention is shown exemplary and schematically.
[0028] The same subjects, functional units, and similar parts are indicated by the same reference numerals in the accompanying drawings. These subjects, functional units, and similar parts are implemented identically in terms of their technical features, unless otherwise expressly or implied in the description. Detailed Implementation
[0029] Figure 1 A possible embodiment of the inspection table 1 according to the present invention is illustrated exemplaryly and schematically. The inspection table 1 includes a rotating drum 2 arranged on a drum shaft 3. The drum shaft 3 here has three translational and three rotational degrees of freedom. The vehicle tire to be inspected (in...) Figure 1(Not shown) rolls on the surface of the drum 2 during its inspection. Furthermore, the inspection table 1 also includes a first force sensor 4, a second force sensor 5, and a third force sensor 6. The first force sensor 4 contacts the first axial end 3' of the drum shaft 3 via a first coupling guide rod 7, and the second force sensor 5 contacts the second axial end 3'' of the drum shaft 3 via a second coupling guide rod 8. The first coupling guide rod 7 itself contacts the first axial end 3' of the drum shaft 3 via a detachable threaded connection, and the second coupling guide rod 8 itself contacts the second axial end 3'' of the drum shaft 3 via a detachable threaded connection. Because the connection between the first or second coupling guide rods 7, 8 and the first or second axial ends 3', 3'' is gapless, hysteresis effects that could lead to inspection errors are avoided. The arrangement of the first force sensor 4 and the second force sensor 5 at the first axial end 3' or the second axial end 3'' allows the first and second force sensors to detect the radial force acting on the drum shaft 3, respectively. Furthermore, particularly in conjunction with the coupling link 12 and the third force sensor 6, the tangential forces acting on the drum 2 can also be detected via the flat cubic coupling guides 7 and 8. The third force sensor 6 is arranged at a right angle relative to the first force sensor 4 and contacts the first axial end 3' of the drum shaft 3 via the coupling link 12. Therefore, the third force sensor 6 can detect the lateral forces acting on the drum shaft 3. Additionally, the third force sensor 6 also contacts the first force sensor 4 via the coupling link and the first coupling guide 7, thereby allowing targeted crosstalk from the first force sensor 4 to the third force sensor 6 and vice versa. The arrangement of the third force sensor 6 allows it to detect the lateral forces acting on the drum shaft 3. The first force sensor 4, the second force sensor 5, and the third force sensor 6 are each constructed as single-axis force sensors, thus they are relatively inexpensive and can be calibrated relatively easily. Therefore, unwanted and undefined crosstalk between the force detection channels of multi-axis force sensors can be avoided from the outset. Figure 1 The inspection table shown is suspended on the support frame 13.
[0030] Figure 2 A possible implementation of the coupling guide 7 is illustrated, for example, preferably used in an inspection table according to the invention. As can be seen, the coupling guide 7 has rows of holes 9 at both axial ends for receiving screws 10, so that the coupling guide can be detachably fastened to the force sensor 4 and the first axial end 3' of the drum shaft by means of a screw connection. Figure 2(Not shown in the image). Furthermore, the coupling guide 7 has a central opening 11 through which the coupling link 12 can be guided, thus enabling targeted crosstalk from the first force sensor 4 to the third force sensor 6 and vice versa. Here, the strength of the crosstalk depends on the length and stiffness of the coupling link 12 and the length and stiffness of the coupling guide 7.
[0031] Figure 3 The drum shaft 3 of the inspection table according to the invention is shown exemplary and schematically. The drum 2 is also shown by dotted lines. Arrow 14 here represents a lateral force acting on the drum shaft, which can be detected by a third force sensor via the coupling link 12. Arrows 15, 15', and 15'' represent radial forces that can be detected by the first and second force sensors 4 and 5 via the first and second coupling guides 6 and 7. Because arrows 15, 15', and 15'', or the associated radial forces, act on the drum shaft 3 at three different locations, a torque is also generated, which also acts on the drum shaft 3. This torque can also be detected by the first and second force sensors 4 and 5 via the first and second coupling guides 6 and 7, and can also be detected by the third force sensor 6 due to the coupling of the first coupling guide 6 with the coupling link 12. Arrows 16 and 16' represent tangential forces that can also be detected by the first and second force sensors 4 and 5 due to the flattened cubic construction of the first and second coupling guides 6 and 7.
[0032] List of reference numerals
[0033] 1 Inspection table
[0034] 2. Rotating drum
[0035] 3 Drum Shaft
[0036] 3' First axial end of the drum shaft
[0037] 3'' Second axial end of the drum shaft
[0038] 4 First force sensor
[0039] 5. Second force sensor
[0040] 6. Third Force Sensor
[0041] 7 First coupling guide rod
[0042] 8 Second coupling guide rod
[0043] 9 holes
[0044] 10 screws
[0045] 11 Opening
[0046] 12 Coupling Link
[0047] 13 Load-bearing frame
[0048] 14 Lateral force
[0049] 15', 15'' radial forces
[0050] 16, 16' Tangential force
Claims
1. An inspection bench (1) for inspecting vehicle tires, the inspection bench comprising a drum (2) on a drum shaft (3) and force sensors for detecting radial forces and lateral forces acting on the drum shaft (3), Its features are, The inspection table (1) includes three single-axis force sensors, which are respectively implemented as a first force sensor (4), a second force sensor (5), and a third force sensor (6). The first force sensor (4) and the second force sensor (5) are arranged to detect radial force, and the third force sensor (6) is arranged to detect lateral force. The first force sensor (4) and the third force sensor (6) are coupled, and the third force sensor (6) contacts the first force sensor (4) via a coupling link and a first coupling guide rod (7). The first force sensor (4) is connected to the drum shaft via the first coupling guide rod (7). (3) The first axial end (3') of the second force sensor (5) is in contact with the second axial end (3'') of the drum shaft (3) via the second coupling guide (8), wherein the third force sensor (6) is in contact with the first axial end (3') of the drum shaft (3) via the coupling link (12), wherein the third force sensor (6) is in contact with the first coupling guide (7) via the coupling link (12), and wherein the inspection table (1) is configured to adjust the radial force limiting crosstalk of the third force sensor (6) by means of the preset length and / or preset stiffness of the coupling link (12).
2. The inspection table (1) according to claim 1. Its features are, The first coupling guide rod (7) contacts the first axial end (3') of the drum shaft (3) by means of a detachable threaded connection, and the second coupling guide rod (8) contacts the second axial end (3'') of the drum shaft (3) by means of a detachable threaded connection.
3. The inspection table (1) according to claim 1 or 2. Its features are, The inspection table (1) is configured to adjust the outward tilt of the drum (2) by means of a first coupling guide (7) and / or a second coupling guide (8) of different lengths and sizes.
4. The inspection table (1) according to claim 1 or 2. Its features are, The inspection table (1) is configured to adjust the tilt direction of the drum (2) by means of the misalignment of the first force sensor (4) and / or the second force sensor (5).
5. A method for inspecting vehicle tires, wherein, The radial force and the lateral force acting on the drum shaft (3) of the rotating drum (2) are detected by force sensors. The device is characterized by detecting radial force using a first force sensor (4) and a second force sensor (5) on a single axis, and detecting lateral force using a third force sensor (6) on a single axis. The first force sensor (4) is in contact with the first axial end (3') of the drum shaft (3) via a first coupling guide rod (7), and the second force sensor (5) is in contact with the second axial end (3'') of the drum shaft (3) via a second coupling guide rod (8). The third force sensor (6) is in contact with the first axial end (3') of the drum shaft (3) via a coupling link (12). The third force sensor (6) is in contact with the first coupling guide rod (7) via the coupling link (12). The radial force crosstalk to the third force sensor (6) is adjusted by means of a preset length and / or a preset stiffness of the coupling link (12). The third force sensor (6) is in contact with the first force sensor (4) via the coupling link and the first coupling guide rod (7).
6. The method according to claim 5, Its features are, The first force sensor (4) and / or the second force sensor (5) and / or the third force sensor (6) are individually calibrated.