Traveling drum

Abstract

To provide a traveling drum which keeps the gap between pseudo road surfaces constant and reduces the variation in test results. [Solution] The running drum 10 rotates while bringing a test tire T into contact with its outer surface, and comprises a drum body 11, a plurality of plates 12 attached and detached to the outer surface of the drum body 11 and divided circumferentially of the drum body 11, and a pseudo road surface 14 formed on the plates 12, the plates 12 being fastened to the drum body 11 by bolts B, and the plates 12 and drum body 11 having positioning portions formed thereon that determine the position of the plates 12 relative to the drum body 11.

Description

[Technical Field]

[0001] The present disclosure relates to a running drum that rotates a test tire while contacting the outer peripheral surface thereof. [Background technology]

[0002] The traveling drum constitutes a drum testing device. Evaluation tests to evaluate tire performance are conducted in the drum testing device. The evaluation tests include, for example, noise tests and vibration tests. The traveling drum has a drum body, a plurality of plates detachably attached to the outer circumferential surface of the drum body and divided in the circumferential direction of the drum body, and a simulated road surface formed on the plates. The traveling drum is rotated while the test tire is in contact with the traveling drum. This allows the test tire to roll on the simulated road surface. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 11-218470 Summary of the Invention [Problem to be solved by the invention]

[0004] In a traveling drum, a plate is fastened to the drum body by a fastening member. More specifically, holes are formed in the plate and screw holes are formed in the drum body, and the plate is fastened to the drum body by a bolt. Generally, the diameter of the hole in the plate is larger than the outer diameter of the bolt. Therefore, the circumferential position of the plate may shift each time the plate is attached to or detached from the drum body. In other words, the gap between the simulated road surfaces may vary each time the plate is attached to or detached from the drum body. In this case, the results of the evaluation test will vary each time the plate is attached to or detached from the drum body.

[0005] Therefore, an object of the present invention is to provide a traveling drum that keeps the gap between the simulated road surfaces constant and reduces the variation in test results. [Means for solving the problem]

[0006] The running drum of the present invention is a running drum that rotates while a test tire is in contact with its outer peripheral surface, and is equipped with a drum main body, a plurality of plates that are attached and detached to the outer peripheral surface of the drum main body and divided in the circumferential direction of the drum main body, and a pseudo road surface formed on the plates, and is characterized in that the plates are fastened to the drum main body by fastening members, and the plates and drum main body are formed with positioning portions that determine the position of the plates relative to the drum main body. [Effects of the Invention]

[0007] According to the traveling drum of the present invention, the gap between the simulated road surfaces becomes constant, thereby reducing the variation in test results. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram illustrating a drum testing device according to an embodiment. [Figure 2] FIG. 2 is a schematic diagram illustrating a traveling drum according to an embodiment; [Figure 3] FIG. 10 is a plan view of a plate showing a positioning portion according to an embodiment. [Figure 4] 4 is a cross-sectional view taken along the line A1-A1 in FIG. 3. [Figure 5] FIG. 10 is a plan view of a plate showing a positioning portion according to another example of the embodiment. [Figure 6] 6 is a cross-sectional view taken along line A2-A2 in FIG. 5. DETAILED DESCRIPTION OF THE INVENTION

[0009] An example of an embodiment of the present invention will be described in detail below. In the following description, specific shapes, materials, directions, numerical values, etc. are examples for facilitating understanding of the present invention, and can be appropriately changed according to the application, purpose, specifications, etc.

[0010] [Drum testing equipment] A drum testing device 100 according to an embodiment will be described with reference to FIG.

[0011] The drum testing device 100 is a device that evaluates the tire performance of a test tire T. The drum testing device 100 includes a test tire T, a traveling drum 10, a tire support unit 110, a drum support unit 120, and a control unit 130, each of which will be described in detail below. The test tire T is a tire whose tire performance is evaluated in the drum testing device 100. The traveling drum 10 is a member that rotates the test tire T while bringing it into contact with its outer circumferential surface. The traveling drum 10 will be described in detail below.

[0012] The tire support unit 110 supports the test tire T by adjusting the position of the test tire T relative to the drum testing device 100 and the load of the test tire T relative to the drum testing device 100. The tire support unit 110 has a tire rotation axis 111, a tire power source 112, a load cell 113, a fixing member 114, and an elevator device 115, which will be described later.

[0013] The tire rotation shaft 111 supports the test tire T so that it can rotate freely in the tire circumferential direction. The tire power source 112 is connected to the tire rotation shaft 111 and applies a driving force or a braking force to the tire rotation shaft 111. The tire power source 112 may be, for example, a motor. The tire power source 112 may use a brake to apply a braking force, or may use both a motor and a brake.

[0014] The load cell 113 is provided on the tire rotation shaft 111. The load cell 113 measures torque and forces in three directions, namely, longitudinal force, lateral force, and vertical force of the test tire T. A fixing member 114 is provided on the tire rotation shaft 111. The fixing member 114 fixes the tire rotation shaft 111 in the direction in which the test tire T presses the traveling drum 10 (the up-down direction in FIG. 1 ).

[0015] The lifting device 115 presses the test tire T against the traveling drum 10. The lifting device 115 also raises and lowers the tire power source 112. This allows the test tire T attached to the tire rotation shaft 111 to be moved closer to or farther away from the traveling drum 10. Instead of the lifting device 115, a lifting device configured to be able to raise and lower the traveling drum 10 may be used.

[0016] The tire support unit 110 adjusts the load of the test tire T to a predetermined value using a lifting device 115 based on the measurement results of the vertical force using a load cell 113, and then fixes the tire rotation axis 111 with a fixing member 114, thereby allowing the test tire T to be grounded on the running drum 10 at a predetermined load.

[0017] The drum support unit 120 has a drum rotation shaft 121 and a drum power source 122, which will be described later. The drum rotation shaft 121 supports the traveling drum 10 so that it can rotate freely in the tire circumferential direction. The drum power source 122 is connected to the drum rotation shaft 121. The drum power source 122 applies a driving force or a braking force to the drum rotation shaft 121. The drum power source 122 may be, for example, a motor.

[0018] The control unit 130 is configured using a computer such as a personal computer or a PLC (Programmable Logic Controller). The control unit 130 has a CPU (Central Processing Unit) which is an arithmetic processing unit, and storage units such as RAM (Random Access Memory) and ROM (Read Only Memory), and performs signal processing according to a program pre-stored in the ROM while utilizing the temporary storage function of the RAM. The control unit 130 is electrically connected to the tire power source 112, the load cell 113, the fixed member 114, the lifting device 115, and the drum power source 122, and is configured to be able to control the operation of each of these units.

[0019] [Traveling drum] A traveling drum 10 as an example of an embodiment will be described with reference to FIGS. 1 and 2. FIG.

[0020] As described above, the traveling drum 10 is a member that rotates the test tire T while keeping it in contact with its outer peripheral surface. As will be described in detail later, the traveling drum 10 keeps the gap between the simulated road surfaces 14 constant, thereby reducing variation in the results of tire evaluation tests in the drum testing device 100. The traveling drum 10 has a drum main body 11, a plate 12 that is detachable from the drum main body 11, a simulated road surface 14 provided on the outer peripheral surface of the plate 12, a fixing portion that fixes the drum main body 11 and the plate 12, and a positioning portion for the drum main body 11 and the plate 12.

[0021] The traveling drum 10 is configured in a substantially cylindrical shape. In the following, each component of the traveling drum 10 may be described according to the drum axial direction, the drum circumferential direction (arrow R in the figure), and the drum radial direction (arrow D in the figure). The axial direction of the outer peripheral surface of the traveling drum 10 may be described as the drum width direction (arrow W in the figure).

[0022] The drum body 11 is a member that serves as the base of the traveling drum 10. The drum body 11 is formed in a substantially cylindrical shape. The drum body 11 is preferably made of an inexpensive and rigid material. The drum body 11 is made of, for example, stainless steel, steel, or aluminum. The drum body 11 is supported by a drum rotation shaft 121 and is configured to be rotatable. The drum body 11 is formed with a screw hole 21 that forms a fixing portion and a hole 31 that forms a positioning portion, each of which will be described in detail later (see FIG. 4).

[0023] The plate 12 is a member that covers the outer peripheral surface of the drum body 11. The plate 12 is also a member that is detachably attached to the outer peripheral surface of the drum body 11. The plate 12 is divided into multiple pieces in the circumferential direction of the drum. In other words, the plates 12 are connected together in the circumferential direction of the drum to form a cylindrical shape. The number of divisions of the plate 12 is not particularly limited. The plate 12 is preferably made of an inexpensive and rigid material. The plate 12 is made of, for example, stainless steel, steel, aluminum, etc.

[0024] The plate 12 has frame portions 13 formed at both ends in the drum width direction, and a pseudo road surface 14 sandwiched between the frame portions 13. The frame portions 13 are formed with fixing holes 22 that form fixing portions and pins 32 that form positioning portions, each of which will be described in detail later (see FIG. 4).

[0025] The pseudo road surface 14 is a member against which the test tire T is pressed when an evaluation test of the test tire T is conducted. The pseudo road surface 14 is configured to simulate the road surface when the evaluation test is conducted. The pseudo road surface 14 is provided on the outer peripheral surface of the plate 12. In other words, the pseudo road surface 14 is arranged along the circumferential direction of the drum. The pseudo road surface 14 is made of materials such as resin, metal, etc. It may also be made of a composite of materials such as aggregate, carbon fiber, glass fiber, etc. It may also be formed by attaching a sheet-like member such as abrasive paper or abrasive cloth to the traveling drum.

[0026] [Fixing the plate to the drum body] A fixing portion as an example of an embodiment will be described with reference to FIGS.

[0027] The fixing portion fixes the plate 12 to the drum body 11. The fixing portion is composed of a bolt B, a screw hole 21 formed in the drum body 11, and a fixing hole 22 formed in the plate 12, each of which will be described in detail later. The screw holes 21 are formed at both ends of the drum in the width direction. The screw holes 21 are preferably formed at equal intervals around the drum circumference. The fixing holes 22 are formed in the frame portion 13 of the plate 12. The fixing holes 22 are formed at positions corresponding to the screw holes 21 when the plate 12 is placed on the outer circumferential surface of the drum body 11.

[0028] At the fixing portion, the bolt B is passed through the fixing hole 22 of the plate 12 and screwed into the screw hole 21 of the drum body 11. This fastens the plate 12 to the drum body 11. As a result, the plate 12 is fixed to the drum body 11.

[0029] Here, the diameter of the fixing hole 22 is larger than the outer diameter of the bolt B. Therefore, the position of the plate 12 in the drum circumferential direction may be shifted every time the plate 12 is attached to or detached from the drum body 11. In other words, every time the plate 12 is attached to or detached from the drum body 11, the gap between the simulated road surfaces 14 may vary. As a result, every time the plate 12 is attached to or detached from the drum body 11, the results of the evaluation test vary.

[0030] In addition, to avoid a situation where a slight misalignment of the plates 12 causes adjacent plates 12 to interfere with each other and prevent the plates 12 from being attached, it is possible to consider a method of increasing the gap between the plates 12 in advance. However, in this case, abnormal noise caused by the gap increases during the evaluation test.

[0031] Therefore, in the traveling drum 10 of this embodiment, the drum body 11 and the plate 12 are positioned by a positioning portion described below.

[0032] [Positioning the drum body and plate] A positioning unit as an example of an embodiment will be described with reference to FIGS.

[0033] The positioning unit positions the plates 12 relative to the drum body 11. More specifically, the positioning unit positions the plates 12 in the drum circumferential direction relative to the drum body 11. The positioning unit makes the gaps between the simulated road surfaces 14 constant, thereby reducing variability in the results of tire evaluation tests in the drum testing device 100. Furthermore, by positioning the plates 12 relative to the drum body 11, the gaps between the plates 12 can be minimized, reducing abnormal noise caused by the gaps during evaluation tests.

[0034] The positioning portion is composed of a recess formed on the outer peripheral surface of the drum body 11 and a protrusion formed on the back surface of the plate 12 (the surface facing the drum body 11) that fits into the recess, as will be described in detail later. Here, for example, if a protrusion is formed on the outer peripheral surface of the drum body 11, there is a possibility that an operator may be injured by the protrusion when the drum body 11 rotates. Therefore, by forming a recess on the outer peripheral surface of the drum body 11, the safety of the drum testing device 100 can be improved.

[0035] The recess in this embodiment is a hole 31. The hole 31 is formed in a hemispherical shape. Note that the shape of the hole in the present invention is not limited to a hemispherical shape. The shape of the hole in the present invention may be, for example, a round hole, an elongated hole, a square hole, a conical hole, or a pyramidal hole. At least two or more holes 31 are formed. This prevents the plate 12 from shifting relative to the drum body 11. As a result, the plate 12 can be reliably positioned relative to the drum body 11. In this case, different types of holes may be formed.

[0036] Each hole 31 is formed at an end of the drum in the width direction. This allows, for example, an evaluation test to be performed by pressing a test tire directly against the drum body 11 without providing the plate 12 (pseudo road surface 14). In this case, the holes 31 do not interfere with the test tire T.

[0037] Each hole 31 is formed along the drum width direction. In other words, the holes 31 are formed at approximately the same position in the drum circumferential direction. Here, for example, if the holes 31 are formed at different positions in the circumferential direction, the depth directions of the holes 31 formed perpendicular to the surface of the arc-shaped plate 12 will not be parallel, and the plate 12 may not be attached to the drum main body 11. Therefore, by forming the holes 31 at approximately the same position in the drum circumferential direction, it is possible to avoid a situation where the plate 12 cannot be attached to the drum main body 11.

[0038] The protrusions in this embodiment are pins 32. The tip of the pin 32 is formed in a hemispherical shape. This makes it easy to insert the pin 32 into the drum body 11 and prevents the drum body 11 from being damaged when the tip of the pin 32 comes into contact with the drum body 11. Alternatively, the pin 32 may be tapered toward the tip, and the tip may be formed in a hemispherical shape. This configuration also makes it easy to insert the pin 32 into the drum body 11 and prevents the drum body 11 from being damaged when the tip of the pin 32 comes into contact with the drum body 11. Alternatively, the pin 32 may be tapered toward the tip, and the tip may be formed flat. This makes it easy to insert the pin 32 into the drum body 11 and allows the depth of the hole 31 to be shallow.

[0039] The pin of the present invention is not limited to a circular shape in a cross section perpendicular to the height direction (hereinafter simply referred to as a cross section). The shape of the pin of the present invention may be polygonal, for example, hexagonal, so as to fit into the hole. In this case, different types of pins, one with a circular cross section and the other with a hexagonal cross section, may be used. Furthermore, the cross sections of the pin and the hole may have different shapes.

[0040] The pins may be provided at different heights, with the higher pins used for preliminary positioning and the remaining lower pins used for accurate positioning.

[0041] The pins 32 are formed at positions corresponding to the holes 31 when the plate 12 is placed on the drum body 11. In other words, at least two pins 32 are formed. The pins 32 are also formed at the ends of the drum in the width direction. Furthermore, the pins 32 are formed along the drum width direction.

[0042] In this embodiment, the positioning portions are configured such that the holes 31 are formed in the drum body 11 and the pins 32 are formed in the plate 12, but the present invention is not limited to this. A pin may be formed in the drum body 11 and a hole that fits onto the pin may be formed in the plate 12.

[0043] [Other embodiments] A positioning unit as another example of the embodiment will be described with reference to FIGS.

[0044] The recess in this embodiment is a groove 41. Only one groove 41 may be formed, or two or more grooves 41 may be formed. The groove 41 is formed along the width direction. The groove 41 is formed at the end in the width direction. This allows, for example, evaluation tests to be performed by pressing a test tire directly against the drum body 11 without providing a plate 12 (pseudo road surface 14). In this case, the groove 41 does not interfere with the test tire T.

[0045] The groove 41 is formed so that the cross-sectional area perpendicular to the direction toward the rail 42 (hereinafter simply referred to as the cross-sectional area) increases toward the rail 42 (described later). The groove 41 is formed, for example, in a triangular shape when viewed in a cross section perpendicular to the direction along the groove 41 (hereinafter simply referred to as the cross-sectional view). Note that the groove of the present invention may be formed in a semicircular shape when viewed in cross section. Here, for example, the rails may be formed so that their cross-sectional areas are the same, for example, they may be formed in a rectangular shape when viewed in cross section. In this case, it is necessary to provide a gap between the rail and the groove (described later) in consideration of the dimensional tolerance of the rail. In this case, the position of the plate 12 in the drum circumferential direction may shift each time the plate 12 is attached to or detached from the drum body 11.

[0046] Therefore, in this embodiment, as described above, the groove 41 is formed to have a large cross-sectional area. This eliminates the need to provide a gap between the groove 41 and the rail 42. As a result, the position of the plate 12 in the drum circumferential direction does not shift every time the plate 12 is attached to or detached from the drum body 11.

[0047] When two or more grooves 41 are formed, the grooves 41 are formed at approximately the same position in the drum circumferential direction. Here, for example, if the grooves 41 are formed at different positions in the circumferential direction, the grooves 41 are formed perpendicular to the surface of the arc-shaped plate 12, but the depth directions of the grooves 41 are not parallel, which may prevent the plate 12 from being attached to the drum body 11. Therefore, by forming the grooves 41 at approximately the same position in the drum circumferential direction, it is possible to avoid a situation where the plate 12 cannot be attached to the drum body 11.

[0048] The convex portions in this embodiment are rails 42. The rails 42 are formed at positions corresponding to the grooves 41 described above when the plate 12 is placed on the drum body 11. The rails 42 are formed at the ends in the drum width direction. Furthermore, the rails 42 are formed along the drum width direction.

[0049] The rail 42 is formed so that the cross-sectional area perpendicular to the direction toward the groove 41 (hereinafter simply referred to as the cross-sectional area) becomes smaller toward the groove 41. The rail 42 is formed, for example, in a triangular shape when viewed in a cross section perpendicular to the direction along the rail 42 (hereinafter simply referred to as the cross-sectional view). The tip end of the rail 42 is formed flat. This makes it possible to avoid a situation where the rail 42 cannot be fitted into the groove 41 due to dimensional tolerances (variations) in the height direction (drum radial direction) of the rail 42 when fitting the rail 42 into the groove 41.

[0050] In this embodiment, the positioning portions are configured such that grooves 41 are formed in the drum body 11 and rails 42 are formed in the plate 12, but the present invention is not limited to this. A rail may be formed in the drum body 11, and a groove that fits into the rail may be formed in the plate 12.

[0051] [summary] The present disclosure is further illustrated by the following embodiments. Configuration 1: A traveling drum that rotates while contacting the outer circumferential surface of the test tire, The drum body and a plurality of plates detachably attached to the outer peripheral surface of the drum body and divided in the circumferential direction of the drum body; A pseudo road surface formed on the plate; Equipped with The plate is fastened to the drum body by a fastening member, The plate and the drum body are formed with positioning portions that determine the position of the plate relative to the drum body. Running drum. Configuration 2: The traveling drum according to configuration 1, The positioning portion determines the position of the plate relative to the drum body in at least the circumferential direction. Running drum. Configuration 3: The traveling drum according to configuration 2, The positioning portions are formed at both ends of the drum body and the plate in the width direction. Running drum. Configuration 4: The traveling drum according to configuration 3, The positioning portion includes a recess formed in the drum body or the plate, and the protrusion that fits into the recess formed in the plate or the drum body. Running drum. Configuration 5: The traveling drum according to configuration 4, The positioning portion includes the recess formed in the drum body and a protrusion that fits into the recess formed in the plate. Running drum. Configuration 6: The traveling drum according to configuration 5, Two or more positioning portions are formed, The protrusion is a pin. The recess is a hole. Running drum. Configuration 7: The traveling drum according to configuration 6, The pins and the holes are formed along the width direction of the drum body and the plate. Running drum. Configuration 8: The traveling drum according to configuration 5, The protrusion is a rail. The recess is a groove. Running drum. Configuration 9: The traveling drum according to configuration 8, The rail and the groove are formed along the width direction of the drum body and the plate. Running drum. Configuration 10: The traveling drum according to configuration 9, a cross-sectional area of ​​the rail perpendicular to a direction toward the groove becomes smaller toward the groove, The groove has a cross-sectional area perpendicular to a direction toward the rail that increases toward the rail. Running drum.

[0052] It should be noted that the present invention is not limited to the above-described embodiment and its modifications, and various changes and modifications are possible within the scope of the claims of this application. [Explanation of symbols]

[0053] 10 Traveling drum, 11 Drum body, 12 Plate, 13 Frame, 14 Simulated road surface, 21 Screw hole, 22 Fixing hole, 31 Hole, 32 Pin, 41 Groove, 42 Rail, 100 Drum testing device, 110 Tire support unit, 111 Tire rotating shaft, 112 Tire power source, 113 Load cell, 114 Fixing member, 115 Lifting device, 120 Drum support unit, 121 Drum rotating shaft, 122 Drum power source, 130 Control unit

Claims

1. A traveling drum that rotates while contacting the outer circumferential surface of the test tire, The drum body and a plurality of plates detachably attached to the outer peripheral surface of the drum body and divided in the circumferential direction of the drum body; A pseudo road surface formed on the plate; Equipped with The plate is fastened to the drum body by a fastening member, The plate and the drum body are formed with positioning portions that determine the position of the plate relative to the drum body. Running drum.

2. The traveling drum according to claim 1, The positioning portion determines the position of the plate relative to the drum body in at least the circumferential direction. Running drum.

3. The traveling drum according to claim 2, The positioning portions are formed at both ends of the drum body and the plate in the width direction. Running drum.

4. The traveling drum according to claim 3, The positioning portion comprises a recess formed in the drum body or the plate, and a protrusion that fits into the recess formed in the plate or the drum body. Running drum.

5. The traveling drum according to claim 4, The positioning portion includes the recess formed in the drum body and the protrusion that fits into the recess formed in the plate. Running drum.

6. The traveling drum according to claim 5, Two or more positioning portions are formed, The protrusion is a pin. The recess is a hole. Running drum.

7. The traveling drum according to claim 6, The pins and the holes are formed along the width direction of the drum body and the plate. Running drum.

8. The traveling drum according to claim 5, The protrusion is a rail. The recess is a groove. Running drum.

9. The traveling drum according to claim 8, The rail and the groove are formed along the width direction of the drum body and the plate. Running drum.

10. The traveling drum according to claim 9, a cross-sectional area of ​​the rail perpendicular to a direction toward the groove becomes smaller toward the groove, The groove has a cross-sectional area perpendicular to a direction toward the rail that increases toward the rail. Running drum.

Images