JP5806370B1 - Crawler belt and crawler unit having the same - Google Patents

Abstract

A crawler unit including a crawler belt or a mobile robot is reduced by providing a crawler belt having a light weight and a simple configuration. The present invention relates to an endless crawler belt 30 that is rotationally driven by sprockets 32 and 33. The crawler belt 30 includes a plurality of crawler plate portions 41 arranged in the rotation direction, and a bendable hinge portion 42 that is formed thinner than the crawler plate portion 41 and connects the adjacent crawler plate portions 41 to each other. The crawler plate portion 41 and the hinge portion 42 are integrally formed of synthetic resin. [Selection] Figure 10

Description

The present invention relates to a crawler unit having endless track which is driven to rotate, and thereby the sprocket.

  Conventionally, as shown in Patent Document 1 below, an inspection robot using a crawler unit including a crawler belt as a moving unit is known. The crawler belt used in the inspection robot includes a plurality of shoes made of rubber or synthetic resin and a link connecting the shoes, and is rotationally driven by a drive mechanism using an electric motor as a power source.

JP 2010-146034 A

  In the crawler belt described in Patent Document 1, rubber or synthetic resin is used as the shoe material, so that a certain amount of weight can be reduced. However, in Patent Document 1, since the shoes are connected by separate links, it is inevitable that the weight is increased by the amount of the link, and a fastening member or the like is additionally required to connect the shoe and the link. become. For this reason, there is a limit to the weight reduction of the crawler belt, and there is room for further improvement.

The present invention has been made in view of the circumstances as described above, by providing a track of light weight and simple structure, and an object thereof is to reduce the weight of the crawler unit comprising a crawler belt.

In order to solve the above-mentioned problems, the present invention is an endless crawler belt that is rotationally driven by a sprocket, and is formed with a plurality of crawler plate portions arranged in the rotation direction and thinner than the crawler plate portion, A plurality of bendable hinge portions for connecting the shoeboard portions to each other, and a plurality of engaging recesses in which regions located on both sides in the width direction of each hinge portion are cut into a shape capable of receiving the teeth of the sprocket. The shoe plate portion and the hinge portion are integrally formed of a synthetic resin, and the width direction dimension of the hinge portion is made shorter than the shoe plate portion with the formation of the engagement recess. (Claim 1).

According to the crawler belt of the present invention, since the crawler plate portion and the hinge portion are integrally formed of synthetic resin, the number of components is different from the case where adjacent crawler plate portions are connected by separate hinge components, for example. Can be significantly reduced, and the weight of the crawler belt can be effectively reduced. Moreover, since the hinge part is thinner than the shoe plate part and can be bent, the crawler belt can be easily formed into an endless shape (annular shape) and used without any problems when wound around the sprocket. Can do. Further, since the engaging recesses are formed in regions located on both sides in the width direction of each hinge portion, and the teeth of the sprocket are engaged with the engaging recesses, the crawler belts are reliably secured while ensuring the operation of feeding the crawler belts by the sprockets. Can be further reduced in weight.

  In the crawler belt of the present invention, the thickness of the thinnest part of the hinge part is set to 0.2 to 0.7 mm in order to ensure the flexibility and strength of the hinge part at a level that does not cause a problem in practice. (Claim 2). In particular, when the thickness is 0.3 to 0.5 mm, both flexibility and strength can be achieved in a balanced manner (claim 3).

  The material of the crawler plate part is not particularly limited as long as it is a material having a hinge characteristic. For example, polypropylene is preferable.

  In the crawler belt according to the present invention, preferably, a grip member made of an elastic body is attached to a surface on the ground contact side of the crawler plate portion.

  According to this configuration, it is possible to improve the gripping performance of the crawler belt, and it is possible to effectively improve the running performance on rough terrain with many irregularities or on slippery snow.

It said gripping member is preferably formed in a hollow shape (claim 6).

  Since such a hollow grip member exhibits a high impact absorption capability and frictional force, it can contribute to an improvement in running performance.

Further, the present invention provides a crawler unit comprising a crawler belt. Specifically, the crawler unit of the present invention includes the above-described crawler belt, a pair of sprockets provided to be engaged with the crawler belt at one end side and the other end side of a region surrounded by the crawler belt, and at least one of the pair of sprockets. And a drive mechanism that rotationally drives one .

According to the present invention, it is possible to reduce the weight of the crawler units.

As described above, according to the present invention, by providing a track of light weight and simple structure, it is possible to reduce the weight of the crawler unit comprising a crawler belt.

1 is a perspective view showing an overall configuration of a mobile robot according to an embodiment of the present invention. It is a perspective view which shows the traveling part of the said mobile robot. It is a top view of the said travel part. It is a side view of the said travel part. It is a bottom view of the said travel part. It is a perspective view which shows one of a pair of crawler units which comprise the said driving | running | working part alone. It is a side view of the said crawler unit. It is a bottom view of the crawler unit. It is a side view of the principal part which removed the main body frame from the crawler unit. It is a perspective view of the state which extracted and assembled only the crawler belt and the sprocket from the crawler unit. It is a bottom view corresponding to FIG. It is a partially expanded side view of the said crawler belt. It is a single perspective view of the grip member attached to the crawler belt. FIG. 13 is a view corresponding to FIG. 12 for describing a modification of the embodiment.

(1) Overall Configuration of Robot FIG. 1 is a perspective view showing the overall configuration of a mobile robot 1 according to an embodiment of the present invention. The mobile robot 1 of this embodiment is a robot for searching or checking in narrow places (such as under the floor of buildings) or disaster areas where human work is difficult, and is remotely operated by a controller (not shown). The mobile robot 1 supplies power to the traveling unit 2 as a moving unit, a stand 3 attached to the upper surface of the traveling unit 2, a camera unit 4 supported by the stand 3, and the traveling unit 2 and the camera unit 4. And a receiver (not shown) for receiving a control signal from the controller.

  The stand 3 includes a flat plate-like support plate 10 and a plurality of suspension members 11 that connect the support plate 10 and the traveling unit 2. Each suspension member 11 includes a coil spring and a damper, and is provided to absorb vibration transmitted from the traveling unit 2 to the camera unit 4.

  The camera unit 4 includes a base portion 15 fixed to the upper surface of the support plate 10, and a camera body 16 that is supported so as to be rotatable in the vertical and horizontal directions with respect to the base portion 15. The camera body 16 includes a lens unit 16a for capturing a surrounding image, an LED light source 16b for illuminating a dark place, an image sensor (not shown) that converts an image introduced from the lens unit 16a into an electrical signal, And a transmitter 17 that transmits an image captured by the element to the outside.

(2) Specific Configuration of Traveling Unit FIGS. 2 to 5 are diagrams showing a specific configuration of the traveling unit 2 and show the traveling unit 2 with the stand 3 and the camera unit 4 removed. As shown in these drawings, the traveling unit 2 includes a pair of left and right crawler units 20 and 20 and a connecting plate 21 that is provided between the crawler units 20 and 20 and connects the two.

  The crawler units 20 and 20 have the same structure. That is, each crawler unit 20 is provided on one end side and the other end side of a region surrounded by the crawler belt 30, a body frame 31 having a U-shaped cross section covering the crawler belt 30, and a region surrounded by the crawler belt 30. A pair of front and rear sprockets 32, 33, a drive mechanism 34 that rotates the crawler belt 30 by driving one side of the sprockets 32, 33 (the sprocket 32 in this embodiment), and the crawler belt 30 are provided via the sprocket 33. A tension controller 35 for adjusting the applied tension, and a suspension mechanism 36 that elastically presses the lower inner surface of the crawler belt 30. In the following, the sprocket 32 on the side driven by the drive mechanism 34 may be referred to as a drive side sprocket, and the other sprocket 33 may be referred to as a driven side sprocket.

  6 to 8 are diagrams showing a single crawler unit 20 as a single unit, FIG. 9 is a diagram showing a main part in which the main body frame 31 is removed from the crawler unit 20, and FIG. 10 and FIG. It is a figure showing the state where only 30 and sprockets 32 and 33 were extracted and assembled. However, in FIG. 10 and FIG. 11, the crawler belt 30 is shown with a grip member 45 described later removed.

  As shown in FIGS. 6 to 11, the crawler belt 30 includes a plurality of crawler plate portions 41 and a plurality of hinge portions 42 that are alternately arranged in the rotation direction.

  The crawler plate portion 41 is formed in a substantially rectangular shape that is long in the width direction of the crawler belt 30 (a direction orthogonal to the rotation direction of the crawler belt 30) in plan view, and has a certain thickness. The hinge portion 42 is formed integrally with the shoe plate portion 41 and connects adjacent shoe plate portions 41 to each other. The hinge portion 42 is formed to be thinner than the crawler plate portion 41 so that it can be bent. More specifically, the hinge portion 42 is formed to have a semicircular recess when viewed from the side, thereby making it thinner than the shoe plate portion 41.

  In this embodiment, polypropylene is used as the material of the crawler belt 30. The reason is that polypropylene is most excellent in hinge characteristics (specificity to withstand repeated bending) among general synthetic resin materials. However, the material that can be used as the crawler belt 30 is not limited to polypropylene as long as it is a synthetic resin having hinge characteristics.

  FIG. 12 is an enlarged side view showing a part of the crawler belt 30. The dimension t shown in the figure represents the thickness of the thinnest part of the hinge part 42, that is, the thinnest part (the part corresponding to the deepest part of the semicircular recess). In the present embodiment, the thickness t of the thinnest portion of the hinge portion 42 is set to 0.3 mm. The hinge part 42 in which the thinnest part is set to such a thickness can be easily bent from the thinnest part.

  However, the thickness t of the thinnest part is not limited to 0.3 mm as long as the flexibility of the hinge part 42 can be ensured. Specifically, the thickness t may be included in the range of 0.2 to 0.7 mm practically. The reason is that if it is smaller than 0.2 mm, the strength of the hinge part 42 is weakened and easily broken, and if it is larger than 0.7 mm, the flexibility of the hinge part 42 is impaired. In particular, when considering the balance between strength and flexibility, the thickness t of the thinnest portion is preferably included in the range of 0.3 to 0.5 mm.

  The thickness T of the crawler plate portion 41 is not particularly limited, but is set to about 3 mm, for example.

  As shown in FIGS. 8, 10, and 11, a plurality of engagement recesses cut into a shape that can receive teeth T (described later) of the sprockets 32 and 33 are formed on the side portions on both sides in the width direction of the crawler belt 30. 43 are formed so as to be arranged at regular intervals. Each engaging recess 43 is formed so as to cut out regions located on both sides in the width direction of the hinge portion 42 including the corners of the crawler plate portion 41.

  The crawler belt 30 having such a shape has a finite length in a predetermined direction (the arrangement direction of the crawler plate portion 41 and the hinge portion 42) in a state before being assembled to the sprockets 32 and 33. The crawler plate portion 41 on one end side in the predetermined direction and the crawler plate portion 41 on the other end side are attached to each other, and the attached crawler plate portions 41 and 41 are hinge parts 46 that are separate from the crawler belt 30. The crawler belt 30 is formed in an endless shape (annular) by being connected via (FIGS. 8 and 11).

  As shown in FIGS. 2 to 9, a grip member 45 made of an elastic body such as foam rubber is attached to the outer surface (surface on the grounding side) of each crawler plate portion 41 in the crawler belt 30. The grip members 45 are provided in a ratio of two for each crawler plate portion 41 and are attached to both side portions in the width direction of each crawler plate portion 41.

  FIG. 13 is a perspective view showing the grip member 45 alone. The grip member 45 has a hollow portion inside, and is formed so that the surface on the side attached to the crawler plate portion 41 has a flat D-shaped cross section. Such a grip member 45 has a flat surface along the outer surface of the shoe plate portion 41, and is connected via a fastening member such as a screw (not shown) or an adhesive means such as a double-sided tape or an adhesive. It is fixed to the crawler plate part 41.

  As shown in FIGS. 6 to 11 (particularly FIG. 10), the drive-side sprocket 32 includes a shaft portion 32b extending in the width direction of the crawler belt 30 and a pair of disk-shaped main bodies attached to the shaft portion 32b with a space therebetween. Part 32a, 32a. A plurality of teeth T that can be engaged with engaging recesses 43 formed on both sides in the width direction of the crawler belt 30 are arranged on the circumferential surfaces of the main body portions 32a and 32a so that they are arranged on the circumference at a constant pitch. It is installed. Such a drive-side sprocket 32 is rotatably supported by the main body frame 31 by inserting a shaft portion 32b into a hole (not shown) provided in a side plate of the main body frame 31. In this support state, each main body portion 32 a of the drive-side sprocket 32 is disposed on one end side of the crawler belt 30, and its teeth T engage with a plurality of engagement recesses 43 of the crawler belt 30.

  The driven side sprocket 33 also has the same structure as the driving side sprocket 32. That is, the driven sprocket 33 has a shaft portion 33b extending in the width direction of the crawler belt 30 and a pair of disk-shaped main body portions 33a and 33a attached to the shaft portion 33b with a space therebetween. A plurality of teeth T that can be engaged with engaging recesses 43 formed on both sides in the width direction of the crawler belt 30 are arranged on the circumferential surfaces of the main body portions 33a and 33a so as to be arranged on the circumference at a constant pitch. It is installed. Such a driven sprocket 33 is rotatably supported by the main body frame 31 by inserting a shaft portion 33b into a hole (not shown) provided in a side plate of the main body frame 31. In this supported state, each main body portion 33 a of the driven side sprocket 33 is disposed on the other end side of the crawler belt 30, and its teeth T engage with the plurality of engaging recesses 43 of the crawler belt 30.

  As shown in FIGS. 6 to 9, the drive mechanism 34 includes an electric motor 51 that is driven by electric power supplied from the battery 5, and a pulley 52 that is coaxially fixed to the shaft portion 32 b of the drive side sprocket 32. A belt 53 is provided between the shaft 51a of the motor 51 and the pulley 52. When the motor 51 is driven, the driving force is transmitted to the pulley 52 via the belt 53, so that the driving-side sprocket 32 is rotationally driven integrally with the pulley 52. Further, the driven side sprocket 33 is driven to rotate synchronously via the crawler belt 30 that is fed and driven by the driving side sprocket 32.

  The tension controller 35 is mainly composed of a coil spring, and the tension applied to the crawler belt 30 is kept constant by pulling the driven sprocket 33 away from the driving sprocket 32 by the elastic force of the coil spring. Playing a role.

  As shown particularly in FIG. 9, the suspension mechanism 36 is disposed at two locations between the driving side sprocket 32 and the motor 51 and between the motor 51 and the driven side sprocket 33 in a side view. Each suspension mechanism 36 includes a pair of front and rear arms 55 whose upper ends are pivotally supported on the body frame 31 and arranged in a letter C shape in a side view, and a pair of rotatable front and rear attached to the lower ends of the arms 55. And a coil spring 57 attached between the arms 55. Then, each arm 55 is pulled in the proximity direction by the elastic force of the coil spring 57, so that the roller 56 attached to each arm 55 is elastically pressed against the lower inner surface of the crawler belt 30. .

  The mobile robot 1 including the traveling unit 2 in which the crawler units 20 having the above-described configuration are combined in left and right directions moves forward, backwards, or turns as follows.

  That is, the mobile robot 1 moves forward when both the motors 51 provided in the pair of crawler units 20 and 20 are normally driven, and moves backward when both the motors 51 of the crawler units 20 and 20 are driven in reverse. . In addition, the mobile robot 1 turns (superficial turning) when the motor 51 of one crawler unit 20 is driven to rotate forward and the motor 51 of the other crawler unit 20 is driven to rotate backward.

(3) Operation As described above, in the mobile robot 1 of this embodiment, the endless crawler belt 30 is used for the traveling unit 2 (the pair of crawler units 20 and 20). The crawler belt 30 includes a plurality of crawler plate portions 41 arranged in the rotation direction, and a flexible hinge portion 42 that is formed thinner than the crawler plate portions 41 and connects adjacent crawler plate portions 41 to each other. The plate part 41 and the hinge part 42 are integrally formed of synthetic resin (in this embodiment, polypropylene). According to such a configuration, the configuration of the crawler belt 30 can be simplified to reduce its weight, and the crawler unit 20 and thus the mobile robot 1 including the crawler unit 20 can be reduced in weight.

  That is, in the above-described embodiment, since the crawler plate portion 41 and the hinge portion 42 are integrally formed of synthetic resin, unlike the case where the adjacent crawler plate portions 41 are connected by separate hinge components or the like, for example, The number of points can be greatly reduced, and the weight of the crawler belt 30 can be effectively reduced. In addition, since the hinge portion 42 is formed thinner than the crawler plate portion 41 and can be bent, the crawler belt 30 can be easily formed endless (annular), and is wound around the sprockets 32 and 33. Can be used without problems.

  In particular, in the above embodiment, the crawler belt 30 is made of polypropylene having excellent hinge characteristics (specifically resistant to repeated bending) and the thickness t (FIG. 12) of the thinnest part of the hinge part 42 is set to 0.3 mm. Further, the strength of the hinge part 42 can be sufficiently ensured while the flexibility of the hinge part 42 is ensured satisfactorily. However, as already described, if the thickness t of the thinnest part is within the range of 0.3 to 0.5 mm, the same performance as the above embodiment can be obtained, and the range of 0.2 to 0.7 mm. If it is within the range, it can withstand practical use.

  Moreover, in the said embodiment, since the grip member 45 which consists of an elastic body is attached to the surface at the side of grounding in each crawler plate part 41 of the crawler belt 30, the gripping performance of the crawler belt 30 can be improved, and there are many unevenness | corrugations. The running performance of the crawler unit 20 on rough terrain or slippery snow can be effectively improved.

  In particular, in the above-described embodiment, since the grip member 45 is formed in a hollow shape, it is possible to sufficiently increase the impact absorption capability and the frictional force, and to improve the running performance of the crawler unit 20 more effectively. .

  Further, in the above embodiment, the plurality of engaging recesses 43 are formed so as to be arranged at regular intervals on the side portions on both sides in the width direction of the crawler belt 30, so that the teeth T of the sprockets 32 and 33 are formed in the engaging recess 43. By engaging the, it is possible to further reduce the weight of the crawler belt 30 while reliably ensuring the operation of feeding the crawler belt 30 by the sprockets 32 and 33.

  Here, as another method for achieving both the weight reduction of the crawler belt and the running performance of the crawler unit, it is conceivable to configure the entire crawler belt with rubber parts (so-called rubber belts). However, when a rubber belt is used, it is necessary to replace the entire rubber belt when it is damaged. Therefore, when the rubber belt is used on a rough road, the rubber belt is frequently replaced, which is not economical. On the other hand, in the above embodiment, since the crawler belt 30 is made of a synthetic resin and the separate grip member 45 is attached to the ground contact surface of the crawler belt 30, the durability of the crawler belt 30 can be improved. . Further, when traveling on a rough road, the grip member 45 that is a grounding part may be damaged, but even in that case, it is economical because only the damaged grip member 45 needs to be replaced.

  In addition, when a rubber belt is used as a crawler belt, especially when the rubber belt has a closed end structure (an integral structure that is completely continuous in an annular shape), it is necessary to remove the body frame one by one in order to replace the rubber belt. The man-hour will increase. On the other hand, when the crawler belt 30 having an open end structure as in the above-described embodiment (formed in a ring shape through a separate part such as the hinge part 46) is used, the crawler belt 30 is temporarily replaced. Even if the necessity arises, the replacement work can be performed without removing the main body frame 31, so that the maintainability can be improved.

  Furthermore, when a rubber belt having a closed end structure is employed, a special (expensive) manufacturing machine needs to be used for molding, but when the crawler belt 30 as in the above embodiment is used, Since the crawler belt 30 can be easily molded using a general-purpose machine tool such as an injection molding machine, a CNC milling machine, or a 3D printer, the manufacturing cost can be effectively reduced.

(4) Examples The inventor of the present application uses a polypropylene crawler belt 30 in which the crawler plate portion 41 and the hinge portion 42 are integrated, and has a size of total length × total height × total width = 270 × 290 × 220 (mm). A mobile robot 1 as shown in FIG. 1 was prepared. Further, a hollow grip member 45 was attached to each crawler plate portion 41 of the crawler belt 30 in the manner shown in FIGS. In contrast, the inventor of the present application, as a comparative example, manufactured a mobile robot using a crawler belt in which a plurality of polypropylene crawler parts are connected by separate metal hinge parts, and the crawler belt has a non-hollow grip. The member was attached. The results of running tests and the like conducted using the above examples and comparative examples will be briefly described below.

  In the embodiment, by using the crawler belt 30 made of polypropylene in which the crawler plate portion 41 and the hinge portion 42 are integrated, compared with the comparative example in which separate hinge parts are used to connect the crawler plate portions to each other. Thus, the weight of the crawler belt 30 was halved (specifically, the weight of the crawler belt in the comparative example was 650 g, whereas the weight of the crawler belt 30 in the example was 320 g). In addition, in the example, by attaching the hollow grip member 45, compared to the comparative example in which the grip member that is not hollow is attached, it succeeded in increasing the upper limit inclination angle that can be climbed (specifically, The upper limit inclination angle of the example was 40 degrees, while the upper limit inclination angle of the comparative example was 38 degrees). Moreover, while improving the gripping performance in this way, the power consumption of the mobile robot 1 of the example was suppressed to be equal to that of the comparative example. This is probably because the energy saving effect due to the weight reduction of the crawler belt 30 almost canceled the increase in power consumption due to the improvement of the gripping performance.

  As can be understood from the above, according to the crawler unit 20 or the mobile robot 1 using the crawler belt 30 of the above-described embodiment, the weight can be sufficiently reduced and the consumption can be improved while improving the running performance. An increase in power can be suppressed.

(5) Others In the above-described embodiment, an example in which the crawler belt of the present invention is applied to the mobile robot 1 for performing a search or inspection in a narrow place (such as under the floor of a building) or a disaster area where human work is difficult has been described. However, the crawler belt of the present invention can be suitably applied not only to such a mobile robot 1 but also to various robots and mobile bodies that use a crawler unit as a moving means. Further, the crawler belt of the present invention may be used as a belt for a belt conveyor.

  Moreover, in the said embodiment, although the hinge part 42 was formed so that it might have a semicircle-shaped recessed part by the side view, for example, like the hinge part 42 'shown in FIG. 14, as a shape which has a triangular recessed part by the side view Also good. Also in this case, the thickness t ′ of the thinnest part (the part corresponding to the apex of the triangle) of the hinge part 42 ′ is set to 0.2 to 0.7 mm, more preferably 0.3 to 0.5 mm. Is good.

DESCRIPTION OF SYMBOLS 1 Mobile robot 20 Crawler unit 30 Crawler belts 32, 33 Sprocket 34 Drive mechanism 41 Crawler plate part 42 Hinge part 43 Engagement recessed part 45 Grip member

Claims (7)

An endless crawler belt driven to rotate by a sprocket,
A plurality of crawler parts arranged in the rotational direction;
A plurality of bendable hinge portions that are formed thinner than the shoe plate portions and connect adjacent shoe plate portions ;
A plurality of engaging recesses in which regions located on both sides in the width direction of each hinge portion are cut out in a shape capable of receiving the teeth of the sprocket ;
The crawler part and the hinge part are integrally formed of synthetic resin ,
A crawler belt characterized in that the dimension in the width direction of the hinge portion is made shorter than that of the crawler plate portion with the formation of the engaging recess . In the crawler belt according to claim 1,
A crawler belt characterized in that the thickness of the thinnest portion of the hinge portion is set to 0.2 to 0.7 mm. In the crawler belt according to claim 2,
A crawler belt characterized in that the thickness of the thinnest portion of the hinge portion is set to 0.3 to 0.5 mm. In the crawler belt according to claim 2 or 3,
A crawler belt characterized in that the material of the crawler plate part and the hinge part is polypropylene. In the crawler belt according to any one of claims 1 to 4,
A crawler belt characterized in that a grip member made of an elastic body is attached to a surface on the ground contact side of the crawler plate portion. In the crawler belt according to claim 5 ,
A crawler belt, wherein the grip member is formed in a hollow shape. The crawler belt according to any one of claims 1 to 6 ,
A pair of sprockets provided to engage with the crawler belt at one end side and the other end side of the region surrounded by the crawler belt;
A crawler unit comprising: a drive mechanism that rotationally drives at least one of a pair of sprockets.

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