Device and method for measuring sliding friction coefficient of wheel

Abstract

The invention discloses a device and a method for measuring the sliding friction coefficient of a wheel. The device comprises a bottom plate, a sliding seat, a sliding plate, a sliding block and a moving mechanism, the sliding seat is arranged at one end of the bottom plate, the moving mechanism is arranged at the other end of the bottom plate, one end of the sliding plate penetrates through the sliding seat in a sliding mode, the other end of the sliding plate is hinged to the sliding block, and the moving mechanism is sleeved with the sliding block. A friction base material is arranged on the surface of the sliding plate, and the sliding plate is in an inclined state. Compared with the prior art, the method has the advantages that the operation is simple, convenient and effective.

Description

Technical Field

[0001] The invention relates to the technical field of sliding friction coefficient measurement, and in particular to a wheel sliding friction coefficient measurement device and a measurement method. Background Art

[0002] The polyurethane wheel installed on the equipment or vehicle as a driving wheel drives the equipment or vehicle through the friction between the polyurethane and the track or the walking road surface; when the equipment or vehicle brakes and stops on a sloped track or road surface, the friction between the polyurethane and the track or the walking road surface prevents slipping. Therefore, it is necessary to measure the sliding friction coefficient when designing polyurethane wheels.

[0003] The currently disclosed method or device for measuring the friction coefficient of a roller is usually to pull the roller to slide by a traction device, and calculate the friction coefficient based on the measured traction force and the normal pressure of the roller on the substrate. In this measurement method, the error of the force measuring device for measuring the traction force will affect the calculated friction coefficient.

[0004] Therefore, it is urgent to design a simpler and more effective measurement method. Summary of the invention

[0005] In view of the above problems existing in the prior art, an apparatus and method for measuring the sliding friction coefficient of a wheel is provided.

[0006] The specific technical solutions are as follows:

[0007] A wheel sliding friction coefficient measuring device; mainly comprising a bottom plate, a sliding seat, a sliding plate, a sliding block and a moving mechanism;

[0008] The sliding seat is arranged at one end of the bottom plate, the moving mechanism is arranged at the other end of the bottom plate, one end of the sliding plate is slidably penetrated through the sliding seat, the other end of the sliding plate is hinged to the sliding block, and the sliding block is sleeved on the moving mechanism;

[0009] Wherein, a friction substrate is arranged on the surface of the slide plate, and the slide plate is in an inclined state.

[0010] The above-mentioned wheel sliding friction coefficient measuring device also has such a feature that the sliding seat includes a vertical plate, a sliding shaft sleeve and a sliding shaft;

[0011] The vertical plate is mounted on the bottom plate, the sliding shaft sleeve is mounted on the side of the vertical plate, the sliding shaft is mounted in the sliding shaft sleeve and can move in the sliding shaft sleeve, the sliding shaft is provided with a mounting hole for installing the slide plate, the slide plate is slidably inserted into the mounting hole, and the sliding shaft sleeve is provided with an avoidance hole for the slide plate.

[0012] The above-mentioned wheel sliding friction coefficient measuring device also has such a feature that the moving mechanism includes a mounting seat, a screw and a screw nut;

[0013] The mounting seat is arranged on the bottom plate, one end of the slider is slidably clamped in the mounting seat, the other end of the slider is sleeved on the screw rod, and the screw rod is sleeved with the screw rod nut.

[0014] The above-mentioned wheel sliding friction coefficient measuring device also has the following characteristics: the side surface of the mounting seat parallel to the axial direction of the screw rod is provided with a scale line, and the side surface corresponding to the slider is provided with a marking line.

[0015] The above-mentioned wheel sliding friction coefficient measuring device is further characterized in that the scale lines are formed by values ​​of tanθ.

[0016] The above-mentioned wheel sliding friction coefficient measuring device also has the following characteristics: a first support and a second support are respectively provided at both ends of the mounting seat, the first support and the second support are both provided on the base plate, and the two ends of the screw rod are respectively passed through the first support and the second support.

[0017] The above-mentioned wheel sliding friction coefficient measuring device also has such a feature that a limiting plate is provided at one end of the slide plate close to the sliding block.

[0018] The above-mentioned wheel sliding friction coefficient measuring device also has the following characteristics, and also includes a wheel bracket, which is provided with a receiving hole for receiving the wheel to be measured, one end of the receiving hole is open, and a rolling member is provided at the open end of the wheel bracket, and the rolling member can roll with the outer side surface of the skateboard.

[0019] The above-mentioned wheel sliding friction coefficient measuring device also has the following feature: fastening holes are provided on two opposite sides of the wheel bracket, and fasteners are passed through the fastening holes and the wheel to be measured for mounting the wheel to be measured on the wheel bracket.

[0020] A method for measuring the sliding friction coefficient of a polyurethane wheel using the above-mentioned wheel sliding friction coefficient measuring device is characterized in that the measuring method comprises:

[0021] Step 1, placing the wheel to be tested on the slide;

[0022] Step 2, operating the moving mechanism in a direction of increasing the inclination to drive the slide to move;

[0023] Step 3, obtaining the θ value or tanθ value when the wheel to be measured starts to slide down.

[0024] The positive effects of the above technical solution are:

[0025] The present invention provides a device for measuring the sliding friction coefficient of a wheel. The wheel to be measured is placed on a skateboard, and a moving mechanism is operated to increase the inclination of the skateboard. The value of the inclination angle θ when the wheel to be measured starts to slide can be obtained, and then the value of tanθ can be obtained, which is the sliding friction coefficient between the wheel to be measured and a substrate. Scale lines and marking lines are directly provided, and the value of tanθ can be directly read, so that the sliding friction coefficient between the wheel to be measured and the substrate can be obtained more directly. Compared with the prior art, the operation is simple, convenient and effective. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a structural schematic diagram of a wheel sliding friction coefficient measuring device of the present invention;

[0027] Figure 2 for Figure 1 A schematic diagram of the cross-sectional structure of;

[0028] Figure 3 It is a schematic diagram of the assembly structure of the wheel bracket and the polyurethane wheel of the present invention;

[0029] Figure 4 It is a structural schematic diagram of the scale line of the present invention.

[0030] In the accompanying drawings: 1, bottom plate; 2, slide plate; 3, slider; 31, lug; 4, vertical plate; 51, avoidance hole; 52, sleeve body; 53, flange; 54, cover plate; 6, sliding shaft; 71, first seat plate; 72, second seat plate; 8, screw rod; 9, screw rod nut; 101, first support; 102, second support; 11, hand wheel; 12, wheel bracket; 122, first bushing; 123, second bushing; 124, third bushing; 13, bearing; 14, bolt; 15, limit plate; 16, hinge shaft; 17, nut; 100, polyurethane wheel; A, scale line; B, marking line. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below through embodiments and in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0032] The serial numbers of the components herein, such as "first", "second", etc., are only used to distinguish the objects described and do not have any order or technical meaning. The "connection" and "coupling" mentioned in this application, unless otherwise specified, include direct and indirect connections (couplings). In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc. are based on the orientation or positional relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention.

[0033] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0034] See also Figures 1 to 4 , showing a preferred embodiment, the wheel sliding friction coefficient measuring device is applied to the measurement of various wheels, for example, the wheel can be a polyurethane wheel 100 and other wheels, and the polyurethane wheel 100 (wheel to be measured) is used as an example for illustration in this embodiment, and the wheel sliding friction coefficient measuring device includes: a bottom plate 1, a sliding seat, a sliding plate 2, a sliding block 3 and a moving mechanism;

[0035] The sliding seat is arranged at one end of the bottom plate 1, the moving mechanism is arranged at the other end of the bottom plate 1, one end of the sliding plate 2 is slidably arranged in the sliding seat, the other end of the sliding plate 2 is hinged to the sliding block 3, and the sliding block 3 is sleeved on the moving mechanism;

[0036] The surface of the slide plate 2 is provided with a friction substrate, and the slide plate 2 is in an inclined state.

[0037] Specifically, the sliding seat includes a vertical plate 4, a sliding sleeve and a sliding shaft 6;

[0038] The vertical plate 4 is installed on the bottom plate 1, the sliding shaft sleeve is installed on the side of the vertical plate 4, the sliding shaft 6 is installed in the sliding shaft sleeve and can move in the sliding shaft sleeve, the sliding shaft 6 has a mounting hole for mounting the slide plate 2, the slide plate 2 slides through the mounting hole, and the slide shaft sleeve has an avoidance hole 51 for the slide plate 2.

[0039] Optionally, in this embodiment, the vertical plate 4 is set as an L-shaped plate. Optionally, in this embodiment, the sliding sleeve is a sleeve-type structure, including a sleeve body 52 and flanges 53 arranged at both ends of the sleeve body 52. ​​The sleeve body 52 has a circular hole, and the avoidance hole 51 is opened on the sleeve body 52. ​​The flange 53 can realize the connection between the sliding sleeve and the vertical plate 4 through structures such as screws and bolts 14. Both flanges 53 are flanges with holes, and a cover plate 54 is also required to be set outside the flange 53 at one end away from the vertical plate 4 to achieve axial blocking positioning of the sliding shaft 6. In another embodiment, one of the flanges 53 at both ends of the sleeve body 52 is set as a flange with holes, and the other is directly set as a flange without holes. The flange with holes is set at the end of the vertical plate 4, and the flange without holes is set at the end away from the vertical plate 4. In this case, it is no longer necessary to set a separate cover plate.

[0040] Optionally, in other embodiments, two vertical plates 4 may be provided, and the two vertical plates 4 are provided in parallel, and in this case, the two ends of the sliding sleeve are respectively mounted on the two vertical plates 4. In this case, a separate cover plate 54 may not be provided.

[0041] The sliding shaft 6 is a round shaft, which is installed in the round hole of the sliding shaft sleeve and can move therein to rotate along with the sliding plate 2 to a certain extent.

[0042] The size of the avoidance hole 51 needs to be larger than that of the mounting hole, mainly because the sliding plate 2 will be displaced relative to the stationary sliding sleeve during the tilting and rotating process.

[0043] The upper surface of the slider 3 is provided with a lug 31 , which extends into the slide plate 2 and is hinged via a hinge shaft 16 .

[0044] Optionally, in this embodiment, the moving mechanism includes a mounting seat, a screw 8 and a screw nut 9;

[0045] The mounting seat is arranged on the bottom plate 1 , one end of the slider 3 is slidably clamped in the mounting seat, and the other end of the slider 3 is sleeved on the screw rod 8 , and the screw rod 8 is sleeved with a screw nut 9 .

[0046] Optionally, a T-slot is provided in the mounting seat, and one end of the slider 3 is slidably clamped in the T-slot so that the slider 3 can slide along the T-slot to guide the slider 3. Optionally, in this embodiment, the mounting seat includes a first seat plate 71 and a second seat plate 72, and a gap is left between the first seat plate 71 and the second seat plate 72, and the gap forms a T-slot.

[0047] Further, the first support 101 and the second support 102 are respectively provided at both ends of the mounting seat, and the first support 101 and the second support 102 are both provided on the bottom plate 1, and the two ends of the screw rod 8 are respectively passed through the first support 101 and the second support 102. Optionally, the first support 101 and the second support 102 can be block-shaped structures or plate-shaped parts. For example, in this embodiment, the first support 101 and the second support 102 are both L-shaped plates. The first support 101 is provided at one end of the mounting seat close to the sliding seat, and the second support 102 is provided at one end of the mounting seat away from the sliding seat.

[0048] Optionally, a hand wheel 11 is provided at one end of the screw rod 8 close to the second support 102 for rotating the screw rod 8. A shoulder or a retaining ring is provided at one end of the screw rod 8 close to the first support 101 to prevent the screw rod 8 from falling out of the first support 101.

[0049] Optionally, a limit plate 15 is provided at one end of the skateboard 2 close to the slider 3. The limit plate 15 is used to achieve the gear limit of the wheel to be measured to prevent the wheel to be measured from slipping out of the skateboard 2. For example, in the present embodiment, a friction substrate is provided on the surface of the skateboard 2. The skateboard 2 is connected or glued to the friction substrate by fasteners. Further, as a preferred embodiment, it also includes a wheel bracket 12, the wheel bracket 12 is provided with a receiving hole for accommodating the wheel to be measured, one end of the receiving hole is open, and a rolling member is provided at the open end of the wheel bracket 12, and the rolling member can slide with the outer side of the skateboard 2. Among them, the wheel bracket 12 is a U-shaped member as a whole, and the wheel to be measured can be installed in the receiving hole. Optionally, in the present embodiment, the rolling member can be a bearing 13 or a roller, etc. The setting of the rolling member allows the wheel to be measured and the wheel bracket 12 to slide smoothly during the sliding process, eliminating the friction force of the outer side of the skateboard 2 on the wheel bracket 12, so that the measurement data is accurate. The receiving hole of the wheel bracket 12 is provided with several sleeves for mounting the wheel to be tested, such as a first sleeve 122 and a second sleeve 123, and a third sleeve 124 is provided in the fastening hole. The design of the sleeves is only for example and is not used to limit the present invention.

[0050] The two opposite sides of the wheel bracket 12 are provided with fastening holes, and fasteners are inserted through the fastening holes and the wheel to be measured to mount the wheel to be measured on the wheel bracket 12. Optionally, the fasteners can be screws, bolts 14 or other structures. The screws and bolts 14 need to be used in conjunction with nuts 17, which will not be described in detail here.

[0051] When measuring a wheel sliding friction coefficient measuring device provided by the present invention: the base plate 1 is placed on a horizontal plane, and the hand wheel 11 is first rotated in a first direction, for example, counterclockwise, to adjust the angle between the slide plate 2 and the base plate 1 to the minimum, and the wheel bracket 12 equipped with the wheel to be measured is placed on the friction substrate, and the wheel to be measured is in positive contact with the friction substrate, and then the hand wheel 11 is rotated in a second direction, for example, clockwise, at this time, the angle between the friction substrate and the base plate 1 gradually increases, and the inclination of the slide plate 2 is increased. When the wheel bracket 12 starts to slide, the value of the inclination angle θ (the acute angle between the slide plate 2 and the horizontal plane) can be obtained by measurement.

[0052] Friction force F = P*f, P is the normal pressure, and f is the sliding friction coefficient. When the wheel to be measured just starts to slide, the value of the friction force is equal to the sliding force T, T = G*sinθ, and the normal pressure P = G*cosθ, so the following deductions can be made: f = F / P, f = T / P, f = G*sinθ / (G*cosθ), and finally f = tanθ. After obtaining the inclination angle θ, the value of tanθ can be calculated to obtain the sliding friction coefficient f. The present invention provides a wheel sliding friction coefficient measuring device, which places the wheel to be measured on a skateboard 2, operates the moving mechanism to increase the inclination of the skateboard 2, and obtains the value of the inclination angle θ when the wheel to be measured starts to slide, and then obtains the value of tanθ, which is the sliding friction coefficient between the wheel to be measured and the substrate. Compared with the prior art, the operation is simple, convenient and effective. No traction device and force measuring device are required, and the measurement operation is simple and convenient, and the results are accurate.

[0053] Further, as a preferred embodiment, a scale line A is provided on the side of the mounting seat parallel to the axial direction of the screw rod 8 , and a marking line B is provided on the corresponding side of the slider 3 .

[0054] The scale lines A are formed by the values ​​of tanθ.

[0055] Optionally, the scale line A is disposed on the outward side of the first seat plate 71 and / or the second seat plate 72 .

[0056] During the measurement, the base plate 1 is placed on a horizontal plane, and the hand wheel 11 is first turned in a first direction, for example, counterclockwise, to adjust the angle between the slide plate 2 and the base plate 1 to the minimum, and the wheel bracket 12 equipped with the wheel to be measured is placed on the friction substrate, and then the hand wheel 11 is turned in a second direction, for example, clockwise. At this time, the angle between the friction substrate and the base plate 1 gradually increases, and the inclination of the slide plate 2 is increased. When the wheel bracket 12 starts to slide, the reading (tanθ value) of the scale line A on the mounting seat corresponding to the mark line B on the slider 3 is directly read, which is the sliding friction coefficient f between the wheel to be measured and the friction substrate. Compared with the prior art, the operation is simple, convenient and effective. No traction device and force measuring device are required, and the measurement operation is simple and convenient, and the results are accurate.

[0057] A method for measuring the sliding friction coefficient of a polyurethane wheel using the wheel sliding friction coefficient measuring device as described above, characterized in that the measuring method comprises:

[0058] Step 1, placing the wheel to be tested on the slide;

[0059] Step 2, operating the moving mechanism in a direction of increasing the inclination to drive the slide to move;

[0060] Step 3, obtaining the θ value or tanθ value when the wheel to be measured starts to slide down.

[0061] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0062] The above embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present invention. It should be pointed out that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention patent shall be subject to the attached claims.

Claims

1. A wheel sliding friction coefficient measuring device, characterized in that: include: Bottom plate, sliding seat, slide plate, slider and moving mechanism; The sliding seat is arranged at one end of the bottom plate, the moving mechanism is arranged at the other end of the bottom plate, one end of the sliding plate is slidably penetrated through the sliding seat, the other end of the sliding plate is hinged to the sliding block, and the sliding block is sleeved on the moving mechanism; Wherein, a friction substrate is arranged on the surface of the slide plate, and the slide plate is in an inclined state.

2. The wheel sliding friction coefficient measuring device according to claim 1, characterized in that: The sliding seat comprises a vertical plate, a sliding shaft sleeve and a sliding shaft; The vertical plate is mounted on the bottom plate, the sliding shaft sleeve is mounted on the side of the vertical plate, the sliding shaft is mounted in the sliding shaft sleeve and can move in the sliding shaft sleeve, the sliding shaft is provided with a mounting hole for installing the slide plate, the slide plate is slidably inserted into the mounting hole, and the sliding shaft sleeve is provided with an avoidance hole for the slide plate.

3. The wheel sliding friction coefficient measuring device according to claim 1, characterized in that: The moving mechanism comprises a mounting seat, a screw rod and a screw rod nut; The mounting seat is arranged on the bottom plate, one end of the slider is slidably clamped in the mounting seat, the other end of the slider is sleeved on the screw rod, and the screw rod is sleeved with the screw rod nut.

4. The wheel sliding friction coefficient measuring device according to claim 3, characterized in that: The side surface of the mounting seat which is parallel to the axial direction of the screw rod is provided with a scale line, and the side surface corresponding to the sliding block is provided with a marking line.

5. The wheel sliding friction coefficient measuring device according to claim 4, characterized in that: The graduation lines are formed by the values ​​of tan θ.

6. The wheel sliding friction coefficient measuring device according to claim 3, characterized in that: The two ends of the mounting seat are respectively provided with a first support and a second support, the first support and the second support are both provided on the bottom plate, and the two ends of the screw rod are respectively passed through the first support and the second support.

7. The wheel sliding friction coefficient measuring device according to claim 3, characterized in that: A T-shaped slot is arranged in the mounting seat, and one end of the sliding block is slidably clamped in the T-shaped slot.

8. The wheel sliding friction coefficient measuring device according to any one of claims 1 to 7, characterized in that: A limiting plate is arranged at one end of the slide plate close to the sliding block.

9. The wheel sliding friction coefficient measuring device according to any one of claims 1 to 7, characterized in that: It also includes a wheel bracket, which is provided with a receiving hole for receiving the wheel to be tested, one end of the receiving hole is open, and a rolling member is provided at the open end of the wheel bracket, and the rolling member can roll with the outer side surface of the skateboard.

10. The wheel sliding friction coefficient measuring device according to claim 9, characterized in that: Two opposite side surfaces of the wheel bracket are both provided with fastening holes, and fasteners are passed through the fastening holes and the wheel to be measured for mounting the wheel to be measured on the wheel bracket.

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