Vehicle tire restraining device

Abstract

To restrain tires pivotably without giving breakage and damage to a vehicle body or tires of a test vehicle and the like.SOLUTION: One end parts 6a of a plate 6 are arranged in front of and behind a front wheel tire 1a of a test vehicle 1 loaded in a roller device 19 of a chassis dynamometer system 2. In the one end part 6a of the plate 6, an arcuate-like free roller 8 group is arrayed so as to clamp the front wheel tire 1a. Each of the free rollers 8 is pivoted pivotably to a bracket 7 on the one end part 6a.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a device for restraining a tire of a vehicle so that the tire can turn. [Background technology]

[0002] As is well known, a chassis dynamometer system is used to perform various measurements such as fuel consumption measurement and exhaust gas measurement during a running test of a test vehicle, and is equipped with a vehicle restraint device that restrains and fixes the test vehicle placed on a roller device. Examples of this vehicle restraint device are disclosed in Patent Documents 1 to 3, for example.

[0003] (1) The vehicle restraint device of Patent Document 1 restricts the longitudinal movement (forward and backward) of the test vehicle by restraining the body of the test vehicle, and performs vehicle testing without steering the tires.

[0004] However, in evaluation tests for autonomous driving (hereinafter referred to as "AD") and advanced driver assistance systems (hereinafter referred to as "ADAS") that detect and avoid the possibility of accidents in advance, steering angle tests are conducted using sensors.

[0005] In this case, if the test vehicle is to be steered by steering, stress other than that in the longitudinal direction is applied to the joint between the test vehicle and the fixing device, which may cause damage to the vehicle body. For example, the rigidity of the side sills in the lateral direction of the vehicle is low, so if the side sills of the test vehicle are fixed, there is a risk of damage due to steering operation.

[0006] (2) The hub nut clamp type vehicle restraint device of Patent Document 2 (see FIGS. 3 and 4 of Patent Document 2) provides freedom of movement to the vehicle body by restraining the hub nut rather than the body of the test vehicle.

[0007] This vehicle restraint device allows for vehicle yawing and other movements, making it possible to simulate conditions identical to those for on-road driving; however, factors such as the number of holes in the tire wheels, hub diameter, wheel offset, and PCD (Pitch Circle Diameter) must be taken into consideration.

[0008] As a result, it becomes necessary to prepare a huge number of combinations of mounting jigs for connecting the vehicle restraint device to the wheel. Preparing a plurality of mounting jigs for each vehicle restraint device and wheel in this way may result in poor workability and increased costs.

[0009] In addition, when attempting to steer during testing of "AD" or "ADAS," the vehicle restraint device will interfere with the tires, resulting in very small movements of the steering angle within a limited range, which may make it difficult to detect accurately.

[0010] (3) The chain-type restraint device of Patent Document 2 (see Figs. 1 and 2 of Patent Document 2) restrains the towing hook of the test vehicle with a chain, etc. Therefore, when evaluating the steering angle and other sensors, stress in the direction other than the front-rear direction, i.e., stress in the left-right direction, is applied to the towing hook, which may damage the towing hook.

[0011] In addition, sensors mounted on the test vehicle may detect the chain-type restraint device as an obstacle, which may interfere with the actual testing and evaluation. Therefore, a vehicle restraint device described in Patent Document 3 has been proposed for testing "AD" and "ADAS." [Prior art documents] [Patent documents]

[0012] [Patent Document 1] Patent Publication No. 2011-33517 [Patent Document 2] Special Publication No. 02-48854 [Patent Document 3] Patent Publication No. 2022-29655 Summary of the Invention [Problem to be solved by the invention]

[0013] According to the vehicle high speed device of Patent Document 3, a sensor for detecting a steering angle is mounted on a test vehicle. A tire fixing device is turned in synchronization with the tires of the test vehicle in response to a detection signal from the sensor.

[0014] However, because the tire fixing device turns in sync with the steering angle, a deviation can occur between the actual steering angle of the tires, which can damage the tires of the test vehicle.

[0015] Furthermore, the vehicle restraint device of Patent Document 3 clamps and secures the vehicle's side sill with left and right clamps, so there is a risk of damage to the vehicle body due to turning of the tires, just like in Patent Document 1.

[0016] The present invention has been made to solve such conventional problems, and has as its object to restrain the tires so that they can turn without causing any damage to the body or tires of the test vehicle. [Means for solving the problem]

[0017] (1) The present invention provides a device for restraining a tire of a vehicle so as to be able to turn, comprising: a tire mounting member for mounting the tire; a group of free rollers arranged in an arc around the tire placed on the tire mounting member and constraining the tire; Equipped with Each of the free rollers is characterized in that it is rotatably disposed vertically.

[0018] (2) In one aspect of the present invention, the tire includes a set of free rollers at the front and rear of the tire, and each set of free rollers may be provided on a pair of plates.

[0019] (3) In another aspect of the present invention, the position of each of the free roller groups can be adjusted by moving each of the plates in the front-rear direction or width direction of the vehicle, and the height of each of the free roller groups can be adjusted by placing spacers under the plates.

[0020] (4) In still another aspect of the present invention, the free rollers are rotatably supported by brackets erected on the plate. In this case, the brackets may be erected inclined in the same direction, and the free rollers may be inclined obliquely.

[0021] The bracket may be provided with an auxiliary roller for preventing the tire from going off the track. The auxiliary roller is preferably disposed at a higher position than the free roller.

[0022] (5) The tire mounting member may be, for example, a roller device of a chassis dynamometer system. Effect of the Invention

[0023] According to the present invention, the tires can be restrained so as to be able to turn without causing any damage or breakage to the body or tires of the test vehicle. [Brief description of the drawings]

[0024] [Figure 1] FIG. [Diagram 2] FIG. [Diagram 3] FIG. 4 is an enlarged view of the free roller and bracket. [Figure 4] A diagram of the plate fixing structure. [Diagram 5] (a) is a perspective view of the tire before turning, and (b) is a perspective view of the tire after turning. [Figure 6] FIG. [Figure 7] FIG. [Figure 8](a) is a perspective view of the tire before turning, and (b) is a perspective view of the tire after turning. [Figure 9] FIG. 11 is a perspective view of a third embodiment. [Figure 10] FIG. [Figure 11] FIG. 4 is an enlarged view of the free roller and bracket. [Figure 12] (a) is a perspective view of the tire before turning, and (b) is a perspective view of the tire after turning. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] Hereinafter, a tire restraint device for a vehicle according to an embodiment of the present invention will be described, in which an example of application to a chassis dynamometer system that simulates the running conditions of a test vehicle will be described.

[0026] That is, the chassis dynamometer system places the tires of a test vehicle on a roller device, connects a dynamometer to the roller device, and transmits the driving force and braking force of the test vehicle to the dynamometer via the roller device to simulate the test vehicle's driving on a road indoors.

[0027] Here, the control device of the chassis dynamometer system is equipped with an "AD / ADAS" sensor evaluation test system that performs evaluation tests such as checking the synchronization and operation of on-board sensors for "AD / ADSA," and performs steering angle tests using the sensors.

[0028] In this case, the tire restraining means employs a structure in which the tires of the test vehicle are restrained by a group of free rollers, thereby enabling steering by steering operation of the vehicle without modifying the body of the test vehicle. Hereinafter, the tire restraining device will be described based on Examples 1 to 3. EXAMPLES

[0029] A first embodiment will be described with reference to Figures 1 to 5. In Figure 1, reference numeral 1 denotes a test vehicle, and reference numeral 2 denotes the chassis dynamometer system.

[0030] <Configuration example> The chassis dynamometer system 2 is equipped with a pit cover 4 that constitutes a floor above the pit 3. A pair of left and right rails 12, each formed with a concave cross section, are embedded in the pit cover 4 along the fore-and-aft direction of the test vehicle 1 (the YY direction in FIG. 5) (see FIG. 4).

[0031] Furthermore, the pit cover 4 has four openings (not shown) formed at positions corresponding to the front and rear wheels (front and rear tires 1a, 1b) of the test vehicle 1. As shown in Figures 1 and 2, each opening is provided with a roller device 19 on which the tires 1a, 1b of the test vehicle 1 are placed. Here, a group of free rollers 8 are arranged in a substantially elliptical shape around the front tire 1a placed on the roller device 19, and restrain the front tire 1a.

[0032] Specifically, as shown in Fig. 2, spacer panels 25 are placed on the front and rear of the roller device 19 on the pit cover 4. A pair of front and rear plates 6 are placed on the spacer panels 25 at a distance that allows the front tire 1a to turn. Each plate 6 is formed in a substantially rectangular shape and is movably attached to the rails 12.

[0033] One end 6a of each plate 6 is formed with a cutout 10 that is curved and cut out in an arc, and each front tire 1a is disposed between the cutouts 10 formed in the front and rear plates 6. A plurality of brackets 7 formed in a substantially rectangular shape are erected by welding or the like along the inner periphery of this cutout 10, thereby forming a group of brackets 7 arranged in an arc.

[0034] Each bracket 7 is formed with a through hole (not shown), and as shown in FIG. 3, a shaft portion 14 is inserted and fixed into the through hole, and a free roller 8 is supported on the shaft portion 14 so as to be freely rotatable.

[0035] That is, a center hole 8a is formed in each free roller 8, and a shaft portion 14 is rotatably inserted through the center hole 8a. As a result, each free roller 8 is disposed approximately vertically on each bracket 7, and the groups of free rollers 8 on the front and rear plates 6 are arranged in an arc on the pit cover 4 so as to sandwich the front tire 1a from the front and rear, as shown in FIG.

[0036] 4 and 5, a pair of front and rear long holes 11 are formed in the other end 6b of each plate 6 along the width direction (XX direction) of the test vehicle 1. A slot nut 18 having a female screw hole is attached to the rail groove 12a of the rail 12 so as to be movable along the YY direction.

[0037] Here, the shaft portion of the bolt 13 is fastened to the female threaded hole through each long hole 11, causing the slot nut 18 to rise and the rail piece 12b of the rail 12 to be sandwiched between the lower end portion 18a of the slot nut 18 and the inner peripheral edge of the long hole 11, thereby fixing the other end portion 6b of the plate 6.

[0038] At this time, the position of the free rollers 8 can be changed in the same direction by loosening the bolt 13 and moving the slot nut 18 in the YY direction. Also, the position of the free rollers 8 can be changed in the same direction by moving the plate 6 in the XX direction along the long hole 11. This makes it possible to freely adjust the position of the free rollers 8 of each plate 6 according to the magnitude of turning of the front tire 1a, etc.

[0039] <Example of operation> The restraint operation during the "AD / ADAS" sensor evaluation test will be described with reference to Fig. 5. Here, the left and right front tires 1a of the test vehicle 1 are placed on the roller device 19, and then one end 6a of each plate 6 is placed in front of and behind each front tire 1a via a spacer panel 25, and the front and rear of the front tire 1a are sandwiched between a group of free rollers 8 as shown in Fig. 5(a).

[0040] As a result, during test driving on the roller device 19, the front tire 1a comes into contact with the free rollers 8, and each free roller 8 rotates synchronously to restrain the front tire 1a. Also, as shown in FIG. 5(b), when the vehicle is steered by a steering operation, the front tire 1a comes into contact with the free rollers 8 in the turning direction one after another, and the front tire 1a is restrained so that it can turn. Therefore, there is no need to clamp the side sill of the test vehicle 1 with left and right clamps as in Patent Documents 1 and 3, and damage to the vehicle body due to steering operation can be avoided. Even if a discrepancy occurs between the detected steering angle and the actual steering angle, the free rollers 8 rotate synchronously, so there is no risk of damaging the front tire 1a of the test vehicle 1 as in Patent Document 3. This provides the following effects.

[0041] (1) Since the position of the plate 6 can be moved in response to the turning of the front tire 1a, by adjusting the position of the group of free rollers 8, it becomes possible to steer the test vehicle by operating the steering wheel without modifying the test vehicle having no towing hook or side sill as described in Patent Documents 1 to 3 and without damaging the vehicle body.

[0042] (2) There is no need to provide sensors on the handlebars to rotate the tire fixing device in sync with the tire, as in Patent Document 3, and there is no need to prepare multiple mounting jigs (attachments) as in the hub nut clamp restraint device of Patent Document 2. This makes it easier to work with and to manage the schedule for vehicle testing.

[0043] Furthermore, since the free rollers 8 rotate synchronously even when they come into contact with the front tire 1a during cornering, steering is not limited to small turns as in the hub nut clamp restraining device of Patent Document 2.

[0044] In addition, in this embodiment, since the front tire 1a is restrained so as to be able to turn by the group of free rollers 8, there is no need to use a sensor for detecting the steering angle as in Patent Document 3, and the present embodiment is fully applicable to vehicles without steering wheels, such as self-driving cars.

[0045] (3) Since there is no need to restrain the body of the test vehicle, the number of objects to be detected by the on-board sensor for AD / ADSA testing can be reduced. This makes it possible to avoid objects being detected as obstacles by the on-board sensor, as in the case of the chain-type restraint device of Patent Document 2.

[0046] (4) Since the tire dimensions of the front tires 1a vary widely, it is preferable to adjust the height of the group of free rollers 8 by changing the number of spacer panels 25 interposed between the pit cover 4 and the plate 6 as necessary. EXAMPLES

[0047] Example 2 will be described with reference to Figures 6 to 8. In this example, as shown in Figures 6 and 7, each bracket 7 is inclined toward the test vehicle 1 at an angle of about 5 degrees to 15 degrees.

[0048] Here, each free roller 8 is rotatably supported by each bracket 7 via a shaft 14, similarly to the first embodiment. Therefore, each free roller 8 is vertically placed at an angle in the same direction as the bracket 7. Here, the front and rear groups of free rollers 8 vertically placed at an angle are each arranged in an arc, and the front tire 1a is sandwiched between the front and rear groups of free rollers 8.

[0049] According to this embodiment, as shown in FIG. 8(b), when cornering, the perpendicular line of the shoulder surface of the front tire 1a and the free roller 8 can come into vertical contact, so that the load applied to the free roller 8 and the front tire 1a can be reduced more than in the first embodiment, thereby enabling the lifespan of the front tire 1a to be extended. EXAMPLES

[0050] A third embodiment will be described with reference to Figures 9 to 11. In this embodiment, each bracket 7 is configured as a double roller type equipped with not only free rollers 8 but also auxiliary rollers 20 for preventing deviation of the front tire 1a. In Figures 12(a) and 12(b), due to space restrictions, only some of the auxiliary rollers 20 are labeled with reference numerals.

[0051] 11, in this embodiment, a support piece 21 is provided upright on the upper portion 7a of each bracket 7, and an auxiliary roller 20 is rotatably and vertically supported on a shaft portion 22 supported by the support piece 21. Here, the auxiliary roller 20 is formed to have a smaller diameter than the free rollers 8, and is disposed at a higher position than the free rollers 8.

[0052] Therefore, according to this embodiment, even if the front tire 1a attempts to pass over the free rollers 8 during test driving of the test vehicle 1, particularly when steering, it hits the auxiliary rollers 20 and is restrained. This makes it possible to reduce the risk of the front tire 1a jumping out, thereby improving safety.

[0053] The present invention is not limited to the above-described embodiment, and can be modified and implemented within the scope of the claims. For example, the present invention can be applied not only to restraining the front tire 1a placed on the roller device 19 of the chassis dynamometer system 2, but also to a free roller device used in vehicle inspection, or a device that can place a tire on a rotating body such as a sphere.

[0054] In addition, in the first to third embodiments, examples of restraining the front tire 1a are shown, but if the test vehicle is a 4WS (four-wheel steering) vehicle, the tire can be used to restrain four wheels including the rear tire 1b.

[0055] Furthermore, as in the second embodiment, a support piece 21 may be formed on the upper portion 7a of the diagonal bracket 7, and an auxiliary roller 20 may be provided. In this case, the free rollers 8 and the auxiliary rollers 20 are placed vertically at an angle, reducing the tire load when preventing the tire from jumping out. [Explanation of symbols]

[0056] 1...Test vehicle 1a…Front tire 1b…Rear tire 2. Chassis dynamometer system 6…Plate 7…Bracket 8…Free roller 19...Roller device 20...Auxiliary roller 22…Spacer panel

Claims

1. A device for restraining a tire of a vehicle so as to be able to turn, comprising: a tire mounting member for mounting the tire; a group of free rollers arranged in an arc shape around the tire placed on the tire mounting member and constraining the tire; Equipped with A tire restraining device for a vehicle, wherein each of the free rollers is disposed vertically and rotatably.

2. The free roller groups are provided in front and behind the tire.

2. A tire restraining device for a vehicle according to claim 1.

3. The free roller groups on the front and rear of the tire are provided on a pair of plates, respectively.

3. A tire restraining device for a vehicle according to claim 2.

4. By moving each plate in the front-rear direction or width direction of the vehicle, 4. A tire restraining device for a vehicle according to claim 3, wherein the positions of the groups of free rollers are adjustable.

5. By placing a spacer under the plate, 4. A tire restraining device for a vehicle according to claim 3, wherein the height of each of said groups of free rollers is adjustable.

6. Each of the free rollers is rotatably supported by a bracket provided upright on the plate.

4. A tire restraining device for a vehicle according to claim 3.

7. Each of the brackets is erected at an incline in the same direction, The free rollers are inclined obliquely.

7. A tire restraining device for a vehicle according to claim 6.

8. An auxiliary roller for preventing the tire from going off the track is rotatably mounted on the bracket.

8. A tire restraining device for a vehicle according to claim 6 or 7.

9. 9. The tire restraining device for a vehicle according to claim 8, wherein the auxiliary roller is disposed at a higher position than the free roller.

10. 2. The vehicle tire restraint device according to claim 1, wherein the tire mounting member is a roller device of a chassis dynamometer system.

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