JPH08127247A - Push and pull drive device using open end roller chain, and opening and closing device for expandable awning of truck using it - Google Patents

Abstract

PURPOSE: To smoothly and surely move back and force by providing inner and outer running guides for guiding roller chain along a predetermined running path and around a drive sprocket so that one end part of inner and outer guides is arranged in parallel with the extension line of a running guide. CONSTITUTION: An object 22 attached to a link piece 11A at the leading end of a roller chain 10 through the intermediary of a connecting piece 20 is moved back and force by rotating a sprocket 16. Running guides 18 clamping roller parts at tops and bottoms of the latter, for guiding the same on horizontal running, are laid, and inner and outer guides 24, 26 adapted to make contact with the link piece 14A at the inner and outer sides in the vicinity of meshing parts of the roller chain 10 and the sprocket 16 are arranged. Further, both guides 24, 26 are composed of curved parts 24a, 26a and horizontal extending parts 24b, 26b facing the proximal end parts 18a of the running guides 18. Accordingly, the open end roller chain 10 can be surely and smoothly moved back and forth, thereby it is possible to enhance the durability thereof and to reduce the weight thereof.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an open-end roller chain push / pull drive device for advancing / retracting a non-annular roller chain, that is, an open-end roller chain, along a predetermined traveling path.
In particular, the present invention relates to an open-end roller chain push / pull drive device suitable for opening and closing, for example, opening and closing of an extendable hood mounted on a bed of a truck by moving the roller chain forward and backward. The present invention also relates to an opening / closing device for an extendable hood on a truck bed using an open end roller chain.

[0002]

2. Description of the Related Art There are various lids for covering the space above the cargo bed of a truck, and one of them is a so-called hood. In this hood, a large number of inverted U-shaped stanchions are attached at intervals in the front-rear direction of a loading platform, and a sheet of cloth or the like is covered so as to cover the large number of hood stanchions.

By the way, generally, the hood on the truck bed is generally of a fixed type so that it can be opened and closed only on the rear side of the truck bed, but by utilizing the characteristics of the hood, it can be opened and closed in a so-called bellows shape. It is conceivable to use it as a hood. As shown in FIG. 14, the telescopic hood on the truck bed has an inverted U shape as a whole on the truck bed 2 of the truck 1.
A plurality of hood pillars 3 having a character shape are provided so as to be movable in the front-rear direction of the loading platform 2, and each hood pillar 3 is connected by a crossbar 4 in which a pair of arms 4A and 4B are combined in an X shape. The plurality of hood columns 3 and crossbars 4 are entirely covered by a hood 9. By moving the hood column 3 back and forth, the hood can be expanded and contracted and opened and closed by the so-called pantograph principle. With such an extendable hood, most of the space on the loading platform is opened when the hood is reduced, so that loading and unloading of articles on the loading platform becomes extremely easy.

By the way, it is extremely difficult for a worker to manually expand and contract the expansion / contraction of the expansion / contraction hood of such a truck. That is, when the telescopic hood is opened / closed, it is necessary to move the hood column 3 having an inverted U shape while properly maintaining the posture orthogonal to the longitudinal direction (front-back direction) of the loading platform. Even if two or more human hands are required, friction between the hood column and its supporting portion on the cargo bed or rattling, or friction between the hood column and the arm and the rattling, etc. Posture is easy to collapse,
In addition, opening and closing the telescopic hood requires a great deal of labor, so that it is actually difficult to manually open and close the telescopic hood.

Therefore, there is a demand for the development of an opening / closing drive device that mechanizes and automates the expansion / contraction opening / closing of the extension hood on the truck bed without relying on human power. However, due to the nature of the truck bed, large, heavy and expensive items must be avoided. Further, the side plate of the truck bed is generally called "a swing plate" and can be tilted by 180 °. Therefore, it is necessary to use an opening / closing drive device that does not prevent the tilt plate from tilting. Since it is exposed to wind and rain and mechanical vibration is applied, it is desired that the structure be mechanically robust, have excellent durability, and be easy to maintain. Further, the trucks have different structures, shapes, and dimensions under the loading platform depending on manufacturers and vehicle types, and a highly versatile telescopic hood opening / closing drive device that can be applied to trucks having such various structures, shapes, and dimensions is desired. Be done. However, the opening and closing drive device for the truck bed telescopic hood that is sufficiently adapted to these demands has not been put into practical use in the past.

In order to open and close the telescopic hood as described above, it suffices to move the hood column in the front-rear direction of the luggage carrier. Therefore, in order to mechanize and automate the opening and closing, the rearmost end of the truck in the front-rear direction is to be moved. It is sufficient to drive the hood column linearly in the front-back direction of the loading platform. However, the length of the truck bed is several meters to 1
Since the distance is 0 m or more, a driving device capable of linear movement over such a long distance is required.

Generally, one of the relatively lightweight and low-cost means for linearly moving an object (in the case of a telescopic hood of a truck, the hood support at the rear end of the telescopic hood) over a long distance is a metal. It is conceivable to use a wire.
In this case, generally, the metal wire is an endless ring, the moving object (the hood column at the rear end of the extendable hood) is coupled to an appropriate portion of the metal wire, and the endless ring-shaped metal wire is turned to the driving side drum. It is conceivable that the object is moved forward or backward by bridging it between the sleeve and the drive-side drum by rotating it by a rotary drive source such as a motor to circulate the metal wire. However, in such a drive device using a metal wire, it is necessary to provide it in a portion below the swing plate, that is, in a lower portion of the load platform so as not to prevent tilting of the swing plate of the truck carrier. However, the lower part of the loading platform is a place where mud and dust on the road are frequently exposed, and therefore the drive unit is likely to be corroded and rusted, and is a place where gravel and pebbles collide.
Deformation and damage easily occur. Moreover, since there are tire houses and various parts and devices in the lower part of the loading platform, and the shape, structure, and dimensions of the parts differ depending on the manufacturer and vehicle type, it is not possible to use the telescopic hood drive device as a general-purpose product. Have difficulty.
For these reasons, a telescopic hood opening / closing drive device using a metal wire has not been put into practical use.

A roller chain is a member similar to a metal wire. Even when a roller chain is used, it is conceivable that the roller chain has an endless annular shape and is bridged between a pair of sprockets and the moving object is fixed at an appropriate position as in the case of using a metal wire. In this case, there are the same problems as when using metal wires,
It was considered difficult to put it into practical use.

[0009]

As described above, not only is it necessary for the opening / closing drive device for the telescopic hood of the truck bed to be space-saving (compact), lightweight, inexpensive and have a long driving distance. It is desirable to avoid a structure in which it is attached to the lower side of the tilt plate (below the side of the bed) due to the relationship with the tilt plate, but such an opening / closing drive device has been put to practical use in the past. There wasn't. Although it is conceivable to use a roller chain for this type of opening / closing drive device, it has been difficult for a general drive device using a conventional roller chain to satisfy the above-mentioned demand.

By the way, in a drive device using a roller chain, as described above, the roller chain is generally formed in an endless annular shape. However, the present inventors have used a non-annular roller chain 5 having an open end (free end) 5A as shown in FIG. The object 6 is attached, and the non-annular roller chain 5 is guided from both sides thereof by the linear traveling guides 7 and is pushed and pulled by the sprocket 8 which is rotatable in both forward and reverse directions, whereby the object 6 is moved forward and backward. I thought to retreat. When the push-pull drive device using such an open end roller chain 5 is used as a telescopic hood opening / closing drive device for a truck bed, the sprocket 8 and its rotational drive source portion (or, further, the base end portion of the traveling guide) are loaded on the bed. It is provided in front of the tilt plate,
It is possible to provide a portion of the traveling guide 7 (or a main portion excluding the base end portion of the traveling guide) on the swing plate. That is, when the telescopic hood is extended (the hood support at the rear end of the telescopic hood is extended to the end of the loading platform), the roller chain is located inside the traveling guide, but the telescopic hood is contracted (expandable The roller chain can be set so as not to be located inside the traveling guide (or its main part) when the hood support at the rear end of the hood is brought close to the front end of the loading platform.
This is because, in that state, even if the traveling guide (or its main part) is provided on the upper portion of the swing plate, it does not particularly hinder the tilting of the swing plate. According to the structure of such an extendable hood opening / closing drive device, it is not necessary to provide various members and devices on the lower side of the swing plate of the loading platform.
It is possible to satisfy the above-mentioned demands.

However, when the device for pushing and pulling the open end roller chain linearly as described above was put into practical use, it was found that in this case, there were the following problems.

That is, when the open end roller chain is pushed and pulled by a sprocket, a part of the roller chain is wound around a part on the outer circumference of the sprocket, and the roller chain is pushed into the linear running guide from the sprocket, However, it was necessary to pull it out, but it became clear that it is easy for the roller chain to not properly enter the running guide especially when it is pushed in. That is, as shown in FIG. 16, when the roller chain 5 separates from the sprocket 8, the separation of the roller chain 5 from the sprocket 8 is delayed, and the roller chain 5 locally bends, so that the roller chain 5 moves. 17 or the roller chain 5 floats up from the sprocket 8 as shown in FIG. 17 and clogs at the entrance of the traveling guide 7 as described above, or the driving force for pushing is not applied. It has been found that it is difficult to smoothly push the chain 5 into the traveling guide 7 to smoothly travel forward, and thus it is easy to cause a situation in which a driven object such as a hood support of an extendable hood cannot be smoothly moved.

The present invention has been made in view of the above circumstances, and provides a push-pull drive device capable of reliably and smoothly advancing / retreating an open-end roller chain having an object to be driven attached to its tip. That is the purpose. Also, especially as an opening / closing drive device that mechanically drives the expansion / contraction of the telescopic hood on the loading platform of the truck, a push / pull drive device using an open-end roller chain is used, and the opening / closing drive device is located below the side of the loading platform. It is an object of the present invention to improve the durability by eliminating the need to provide it in the space, and to save space (downsize), reduce the weight, and reduce the cost.

[0014]

According to a first aspect of the present invention, a roller chain formed by connecting a plurality of rollers to each other by a link is made non-annular having an open end, and the roller chain has a tip end portion. In a device for pushing and pulling the object by attaching an object and advancing and retracting a portion near the tip of the roller chain along a predetermined running path that is linear or smooth curved, A linear or smooth curved running guide for guiding the running of the portion near the tip of the roller chain sandwiching the roller chain from both sides, and meshing with the roller of the roller chain. Forward and backward rotatable sprocket provided near the base end of the traveling guide to move the roller chain forward and backward. , An inner guide for guiding the roller chain by abutting or facing a link of the roller chain meshing with the sprocket in the vicinity of the sprocket from a side close to the rotation center axis of the sprocket and the sprocket in the vicinity of the sprocket. An outer guide for guiding the roller chain in contact with or facing the link or roller of the meshed roller chain from the side remote from the rotation center axis of the sprocket, It is characterized in that an end portion on the traveling guide side is configured to be parallel to an extension line of the traveling guide.

According to a second aspect of the present invention, there is provided a push / pull drive device using an open end roller chain, wherein in the device according to the first aspect, the distance between the leading end of the inner guide on the side of the running guide and the base end of the running guide is small. The distance is set to be smaller than the distance between the centers of adjacent rollers of the roller chain.

Further, the push-pull drive device by the open end roller chain of the invention of claim 3 is the device of claim 1, wherein the traveling guide is arranged in a horizontal straight line and the sprocket is horizontal. The roller chain is arranged so as to have an axis, and the roller chain is arranged to run with the axis of the roller being horizontal.

According to a fourth aspect of the present invention, there is provided a push-pull drive device using the open-end roller chain according to the third aspect, in which the base end side of the roller chain suspended from the sprocket is below the sprocket. A storage box with an open upper surface is provided for storing the portion of FIG.

On the other hand, the invention of claim 5 relates to an opening / closing device for an extendable hood of a truck provided with a push / pull drive device using the open end roller chain of the invention of claim 1. Specifically, the invention of claim 5 is a device for expanding and contracting an expandable and retractable hood, which is capable of expanding and contracting by moving a hood strut on a cargo carrier of a truck along the front-back direction of the cargo carrier, The travel guide in the push-pull drive device using the open-end roller chain according to claim 1 is horizontally provided on an upper portion of a side plate of a truck bed, and the lower portion of the hood column on the rear end side of the truck is the object. The roller chain is attached to the tip of the roller chain.

In the push-pull drive device using the open-end roller chain according to the first aspect of the present invention as described above, the non-annular roller chain is provided with the driving force by the rotation of the sprocket at the portion engaged with the sprocket. , The part near the tip of the sprocket is moved forward or backward along the running guide. Therefore, the object attached to the tip of the roller chain is pushed and pulled along a predetermined traveling path. The travel guide guides the travel by sandwiching the roller chain from both sides.

Here, in the vicinity of the sprocket, is the roller chain partly engaged with the sprocket and is inserted (pushed) into the entrance (proximal end) of the running guide near the position out of the engagement? Or it will be pulled out from the driving guide. In the vicinity of such a sprocket, the link part of the roller chain inside the roller chain (the side closer to the rotation center axis of the sprocket) is guided by the inner guide, and at the outside of the roller chain (the side farther from the rotation center axis of the sprocket). ) Is guided by the outer guide, and the traveling posture from the position meshing with the sprocket to the traveling guide entrance is regulated. That is, since the ends of the inner guide and the outer guide on the traveling guide side are parallel to the extension lines of the traveling guide, a driving force in the forward direction is applied to the roller chain from the rear side of the roller chain by the sprocket during the pushing drive. If so, the roller chain is properly guided toward the traveling guide by the inner guide and the outer guide from a position that should be originally separated from the sprocket, and is smoothly pushed into the traveling guide. Therefore, prevent the situation where the position where the roller chain separates from the sprocket lags behind the correct position and the roller chain bends between the sprocket and the running guide, or the sprocket lifts from the roller chain. You can

According to the second aspect of the present invention, the distance between the tip of the inner guide and the base end (entrance end) of the running guide is set smaller than the center-to-center distance between adjacent rollers. If the link falls into the gap between the tip of the inner guide and the base of the travel guide (or bends in the gap),
It can be prevented more reliably and effectively.

Further, the invention of claim 3 shows the most general directionality (posture) when the push-pull drive device of the present invention is used. Problems tend to occur, and therefore the effects of the inventions of the present application are most effectively exerted in the case of the posture defined in the invention of claim 3.

According to the invention of claim 4, when the roller chain is driven forward (pushed toward the travel guide), the roller chain folded from the storage box is smoothly pulled out and retracted (pulled out from the travel guide). ) When driven, the roller chain is folded and stored in the storage box.

Further, a fifth aspect of the present invention is an application of the push-pull drive device of the first aspect of the invention to an extendable hood opening / closing device for a truck bed. In this case, the traveling guide is horizontally provided above the side plate of the truck bed, and the lower part of the hood column on the rear end side of the truck is attached to the tip end side of the roller chain. By pushing and pulling the roller chain by the rotation, the hood support on the rear end side of the loading platform is pushed and pulled in the length direction (front-back direction) of the loading platform of the truck, and the telescopic hood is opened and closed. Here, the traveling guide may be provided on the upper part of the side plate of the luggage carrier as described above, but the side plate of the luggage carrier is often composed of a tilting plate which can be tilted in a normal truck. However, since the roller chain is non-annular, the roller chain is not located in the travel guide or the base end of the travel guide when the hood is contracted near the front end of the truck bed or in front of the bed. Since it is located only in the vicinity, even if the entire traveling guide or the main part except the base end is fixed to the tilt plate, the presence of the roller chain will prevent the tilt of the tilt plate. There is no such thing.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the overall construction of a push-pull drive device according to an embodiment of the present invention, and FIGS.

The roller chain 10 is composed of a large number of rollers 12 connected by links 14, respectively.
Adjacent links 14, 14 at the position of each roller 12
The rollers are rotatable relative to each other, and the roller chain 10 is bendable as a whole. Each link 1
4 is composed of a pair of parallel link pieces 14A and 14B, respectively.
The roller 12 is located between B. An object 22 to be driven back and forth is attached to the link piece 14A at the tip of the roller chain 10 via the connecting piece 20. The sprocket 16 is rotatably arranged so that its shaft 16A is horizontal.
6A is connected to a rotary drive source such as a motor (not shown) directly or via a rotation transmission mechanism (not shown),
Alternatively, it is connected to a manual rotation operation means such as a manual rotation handle and can be rotated in both forward and reverse directions. And on the outer periphery of this sprocket 16,
The roller chain 10 is hung on a portion (upper left portion) of about 1/4 of the entire circumference. Here, the teeth 16B of the sprocket 16 are the same as those of the link 14 of the roller chain 10.
The inside of the pair of link pieces 14A and 14B meshes with the roller 12. On the other hand, below the sprocket 16, a storage box 17 having an open upper surface is arranged. This storage box 1
Reference numeral 7 is for accommodating the part of the roller chain 10 suspended from the sprocket 16 on the base end side in a zigzag-folded state.

Upper outer periphery of sprocket 16 (top position)
The horizontal straight running guide 18
Is provided. The traveling guide 18 is for guiding the horizontal traveling of the roller chain 10 by sandwiching the roller 12 portion of the roller chain 10 above and below, and the lower guide portion 18A for receiving the lower side of the roller 12 and the roller 12. Has an upper guide portion 18B facing or facing the upper surface of the roller chain, and these lower guide portion 18A and upper guide portion 18B are connected to each other by a U-shaped connecting portion 18C on the side of the roller chain 10. It is made as one. The lower guide portion 18A and the upper guide portion 18B of the traveling guide 18 are a pair of parallel link pieces 14 that form the link 14 of the roller chain 10.
The intervals are set so as to project to the inside of A and 14B.

On the other hand, the roller chain 10 is the sprocket 1
In the vicinity of the portion meshing with 6, the inner guide 24 for guiding the roller chain 10 by coming into contact with the link 12 of the roller chain 10 from the inside (that is, from the side close to the rotation center axis of the sprocket 16) and the roller chain 10 are provided. The roller chain 10 is brought into contact with the link 14 from the outside (that is, from the side far from the rotation center axis of the sprocket 16).
And an outer guide 26 for guiding the.
The inner guide 24 is composed of a pair of parallel inner guide pieces 24A and 24B. These inner guide pieces 24A and 24B are links of the links 14 of the roller chain 10 meshed with the sprocket 16. Piece 14A,
A curved portion 24a that is curved with a radius of curvature substantially the same as the radius of curvature of the inner diameter of the teeth 16B of the sprocket 16 along about 1/4 circumference (upper left portion) of the sprocket 16 so as to individually contact 14B from inside respectively. , A horizontal extending portion 24b extending horizontally from a position corresponding to the top of the outer periphery of the sprocket 10 along the tangential direction thereof toward the base end portion (entrance portion) 18a of the traveling guide 18 is integrally formed. It is configured. The outer guide 26 is made of, for example, a U-shaped channel member, and the outer guide 26 constitutes the link 14 of the roller chain 10 meshing with the sprocket 16 and forms a pair of parallel link pieces 14.
A curved portion 26a that is curved with a radius of curvature slightly larger than the radius of curvature of the outer diameter of the tooth 16B of the sprocket 16 along about 1/4 circumference (upper left portion) of the sprocket 16 so as to contact the A and 14B simultaneously from the outside. , A horizontal extending portion 26b extending horizontally from the position corresponding to the apex of the outer periphery of the sprocket 16 along the tangential direction thereof toward the base end portion (inlet portion) 18a of the traveling guide 18 is integrally formed. It is configured. The distance between the tip end surface of the inner guide 24 and the base end surface (entrance surface) of the traveling guide 18 (correctly, the distance in the traveling guide length direction when viewed from the side as shown in FIG. 2) W1 Is preferably as small as possible, and at least smaller than the center-to-center distance L1 between adjacent rollers 12 of the roller chain 10. Further, the distance between the tip end surface of the outer guide 26 and the base end surface (entrance surface) of the travel guide 18 (correctly, the distance in the travel guide length direction when viewed from the side surface side as shown in FIG. 2) W2 Is also preferably as small as possible, which is also preferably smaller than the center-to-center distance L1 of the rollers 12 of the roller chain 10.

When the push-pull drive of the object 22 is performed by using the push-pull drive device as described above, as shown in FIGS.
The sprocket 16 is rotated in the clockwise direction in FIGS. 1 and 2 by a rotating means (not shown) in a state of meshing with a part of the teeth 16B on the outer periphery (upper left 1/4 circumference). As a result, the roller chain 10 is fed out from the storage box 17,
It is moved from the lower left of FIGS. 1 and 2 to the right.
At this time, in each link 14 of the roller chain 10, the curved portion 24a of the inner guide 24 and the curved portion 26a of the outer guide 26 are provided at the portion (the upper left quarter circle portion) that should be normally meshed with the sprocket 16. Since they are in contact with each other or face each other, the roller chain 10 meshes with the sprocket 16 from the lower left of FIGS. 1 and 2 to the top position of the sprocket 16 by the curved portions 24a and 26a of the inner guide 24 and the outer guide 26. Guided while curving. Therefore, the roller chain 10 is prevented from coming off the sprocket 16. Subsequently, the roller chain 10 is guided by the horizontal extension portion 24b of the inner guide 24 and the horizontal extension portion 26b of the outer guide 26 so that the roller chain 10 moves horizontally rightward from the sprocket top position toward the running guide 18. . That is, the driving force in the clockwise direction is applied to the roller chain 10 at the portion meshing with the sprocket 16, but the roller chain 10 meshes with the sprocket 16 due to the presence of the horizontal extending portion 24 b of the inner guide 24. It is prevented that the sprocket 16 is circulated from the top of the outer circumference to the lower right, and the roller chain 10 is forcibly disengaged from the sprocket 16 in the horizontal direction from the top of the outer circumference of the sprocket 16. And then the inner guide 2
4 of the horizontal extension 24b and the horizontal extension 2 of the outer guide 26
With 6b, the roller chain 10 is correctly guided horizontally toward the base end (entrance) 18a of the running guide 18. Therefore, the roller chain 10 is attached to the sprocket 16
It is prevented that the sprocket 16 is bent downward or disengaged upward while being engaged with the sprocket 16 between the top position of the roller guide 10 and the traveling guide 18, and the roller chain 10 is linearly pushed into the traveling guide 18. Get caught

In the traveling guide 18, the lower guide portion 18A and the upper guide portion 18B are in contact with or opposite to the rollers 12 of the roller chain 10, so that the horizontal linear traveling of the roller chain 10 is guided. Further, in this running guide 18, since the lower guide portion 18A and the upper guide portion 18B project to the inside of the pair of parallel link pieces 14A and 14B of the link 14 of the roller chain 10, the roller chain 10 is detached laterally. It is also prevented.

Since the object 22 is attached to the link piece 14A at the tip of the roller chain 10, the roller chain 10 is guided by the running guide 18 as described above.
By guiding the vehicle horizontally to the right,
The object 22 can be linearly moved (moved forward) to the right.

When the forward drive of the sprocket 16 is started by the clockwise rotation, the tip end portion of the roller chain 16 is the base end portion (entrance portion) 1 of the running guide 18.
It may not be inserted in 8a. That is, if at least a part of the roller chain 10 meshes with a part of the sprocket 16, the sprocket 16 gives a forward drive force to the roller chain 10.
Moreover, the tip of the roller chain 10 is attached to the running guide 18.
If forward drive is applied to the roller chain 10 from a state where the roller chain 10 is not inserted in the base end portion 18a of the roller chain, the roller chain is driven by the functions of the inner guide 24 and the outer guide 26, particularly the horizontal extending portions 24b and 26b. 10
This is because the tip of the guide is guided straight to the entrance of the travel guide 18 without bending.

On the other hand, if the sprocket 16 is rotationally driven in the counterclockwise direction in FIGS. 1 and 2, the roller chain 10 is linearly moved to the left while being guided by the traveling guide 18, and the traveling guide 18 is sequentially guided, contrary to the above. From the sprocket 16 and is hung downward from the sprocket 16 and stored in the storage box 17 in a zigzag shape. And roller chain 10
The object 22 attached to the tip of the roller chain 10 moves linearly to the left along with the linear movement (backward) to the left.

In the above embodiment, the outer guide 26 is
The portion of the link 14 of the roller chain 10 (link piece 14
Although the outer guide 26 is configured to abut or face the portion of the roller 12 of the roller chain 10 so as to guide the roller chain 10 in some cases, the outer guide 26 is configured to abut or face the roller chains 10. FIG. 6 shows an example of this case corresponding to FIG. In this case as well, it is needless to say that the outer guide 26 is configured such that the curved portion and the horizontal extending portion are integrally continuous. Further, in this case, it is desirable that the outer guide 26 be configured to project to a position between the pair of parallel link pieces 14A and 14B that form the link 14.

Further, in the above-mentioned embodiment, the traveling guide 1
Although 8 is configured in a linear shape, it may have a smooth curved shape depending on the use of the advancing / retreating drive device of the present invention, and in that case, the object 22 can be advancing / retreating driven along a smooth curve. .

FIGS. 7 and 8 show an example in which the advancing / retreating drive device of the embodiment shown in FIGS. 1 to 5 is applied to an opening / closing drive device for an extendable hood that covers a truck bed.

In FIGS. 7 and 8, the truck 30 is provided with a driver's seat portion 32 at its front part and a cargo bed 34 at its rear side. Then, the side plates 36A, 36 on both sides of the loading platform 34 (on the left and right sides with respect to the traveling direction of the truck)
B is a swing plate that can be tilted outward by about 180 °.

Between the side plates 36A and 36B of the loading platform 34, a plurality of hood columns having a substantially inverted U-shape (including a U-shape in which the open side faces downward) when viewed from the traveling direction. 40 are bridged in an upright state, and the plurality of hood columns 40 are arranged at predetermined intervals in the front-rear direction of the luggage carrier. And adjacent hood columns 40, 4
The spaces between 0 are connected by a crossbar 42 composed of a pair of arms 42A and 42B, whereby a plurality of hood columns 4 are provided.
0 is configured to expand and contract in the front-back direction in a pantograph shape. The top and sides of the hood column 40 are covered with a hood (sheet) 44 such as canvas.

Side plates 36A, 3 on both the left and right sides of the loading platform 34
On the upper surface of 6B, a main portion 181 (a portion excluding the base end portion 182) 181 of the traveling guide 18 which is linear along the length direction is provided, and the side plates 36A and 36B of the loading platform 34 are provided. A base end portion 182 of the traveling guide 18 is provided at a portion (fixed portion) in front of the travel guide 18. That is, the traveling guide 18 is separated into a base end portion 182 on the side closer to the sprocket 16 and a main portion 181 on the side plates 36A and 36B ahead of the base end portion 182. The sprocket 16, the inner guide 24, and the outer guide 2 are fixed to the fixed portion in front of the base end portion 182 of the traveling guide 18.
6, a rotational drive source (not shown) for rotating the storage box 17, and the sprocket 16 in both forward and reverse directions is provided. The roller chain 10 is hung on the sprocket 16 as described above, and the link at the tip of the roller chain 10 is connected to the top hood column 40 at the rear end of each hood column 40.
1 is connected. That is, the top hood column 4 at the rear end
01 corresponds to the above-mentioned object 22. Although the detailed structure of the lower end of the other hood column 40 is not shown, in reality, the traveling guide 18 (181, 182)
It is desirable that a guide rail is provided integrally with the top rail, and the guide rail supports the lower end of each hood column and guides the movement of each hood column 40 in the front-rear direction.

In the opening / closing drive device for the extendable hood as described above, as is apparent from the above description, the sprocket 16 is rotated to linearly move the roller chain 10 back and forth to thereby move the hood support column 40 out of the hood column 40. A forward / backward driving force is applied to the hood column 401 at the rearmost end, whereby the whole hood column 40 can be expanded and contracted in a pantograph shape to open and close the hood.

Here, the tip of the roller chain 10 is the main portion 1 of the running guide 18 in the state in which the telescopic hood is in the most contracted state, that is, in the state in which the rearmost hood column 401 is most advanced.
If the layout is such that it is pulled out completely from 81, the side plates 36A, 36B when the telescopic hood is at the minimum contraction.
The roller chain 10 is not located in the upper part, and the whole hood column 40 (401) is not located in the part of the side plates 36A and 36B, but is brought closer to the part in front of the side plates 36A and 36B. Therefore, in that state, the side plates 36A, 36B
Can be tilted.

In the examples shown in FIGS. 7 and 8, the entire length of the running guide 18 is provided on the upper surfaces of the side plates 36A and 36B. However, in some cases, the running guide 18 has its proximal end portion (see FIG. 7). The left end part) and the remaining main part on the right side are separated, and the main part is provided on the upper surfaces of the side plates 36A, 36B, and the base end part is located on the fixed side of the truck (front side of the side plates 36A, 36B). Part). In this case, if the distance between the fixed-side base end portion 182 of the traveling guide 18 and the side plate-side main portion 181 is made small, the roller chain is moved from the base end portion 182 of the traveling guide 18 to the main portion even during extension driving. It can be smoothly inserted into 181.

The push-pull drive device according to the present invention can be applied as an open / close drive device to an extendable hood of a truck carrier, an extendable hood of various other containers, or an extendable hood of a temporary tent.

9 to 11 show a push-pull drive device according to still another embodiment of the present invention. In the embodiments shown in FIGS. 9 to 11, the same elements as those in the above-mentioned embodiments are designated by the same reference numerals, and the description thereof will be omitted.

In the embodiment shown in FIGS. 9-11,
The main difference from each of the above-described embodiments is that neither the inner guide 24 nor the outer guide 26 is curved and is a straight line along the horizontal direction. That is, FIG.
In the embodiment shown in FIG. 11, the inner guide 24 extends horizontally and linearly from the position corresponding to the outer peripheral apex of the sprocket 16 along the tangential direction thereof toward the base end (entrance) 18a of the traveling guide 18. It is configured to do. The inner guide 24 has a tip-side portion (left-hand side portion in FIG. 9) branched into a bifurcated shape (fork shape), and a part of the sprocket 16 is provided between the tips of the branched portions 24c and 24d. Is located. The inner guide 24 is configured to contact the link pieces 14A and 14B of the roller chain 10 as in the above-described embodiments. On the other hand, the outer guide 26 is located from a position before the apex of the outer periphery of the sprocket 16 (a position on the left side in FIG. 9),
Cross the top of the outer periphery of the sprocket 16 and pass the running guide 18
Is extended horizontally and linearly toward the base end (entrance) 18a. Incidentally, the outer guide 26 in the case of this embodiment
Is configured to contact the roller 12 of the roller chain 10 or to face the roller 12 to guide the roller chain.

In the case of the embodiment shown in FIGS. 9 to 11, both the inner guide 24 and the outer guide 26 are mere linear shapes, so compared with the case of the embodiment of FIGS. 1 to 5 having a curved portion. Therefore, the processing cost can be significantly reduced.

In the push-pull drive device of the present invention, the roller chain 10 may be made of engineering plastic in order to reduce the weight and the driving force. In this case, generally, the roller portion and the inner link piece portion are often made of engineering plastic, and the outer link piece is often made of metal. When such a roller chain 10 is used, it is desirable that the traveling guide 18 that guides the traveling of the roller chain 10 be configured as shown in FIG. 12 or 13.

That is, in the case of FIG. 12, the traveling guide 18
Both of the upper guide portion 18B and the lower guide portion 18A are made to contact the portion of the inner link piece 14a made of engineering plastic in the roller chain 10. In the case of FIG. 13, the traveling guide 18
The upper guide portion 18B of the roller chain 10 is in contact with the portion of the roller 12 made of engineering plastic in the roller chain 10, and the lower guide portion 18A of the roller chain 10 is in contact with the portion of the inner link piece 14a.

[0049]

According to the push-pull drive device of the present invention, the open-end roller chain having the object to be driven attached to the tip can be reliably and smoothly moved forward and backward. In addition, especially the expansion and contraction (opening and closing) of the expansion hood of the loading platform of trucks
If it is used as a telescopic hood opening / closing drive for mechanically performing the operation, even if the side plate of the truck bed is a tiltable tilting plate, it is not necessary to provide the opening / closing drive on the lower side of the bed. The durability can be sufficiently improved without being affected by the above. In addition, since the open-end type roller chain is used, the number of parts can be reduced as compared with the case where an endless annular roller chain is used, and space saving, weight reduction and cost reduction can be achieved.

[Brief description of drawings]

FIG. 1 is a partially omitted side view showing an overall configuration of a push-pull drive device according to an embodiment of the present invention.

FIG. 2 is a partially enlarged side view showing a situation near a sprocket of the apparatus shown in FIG.

FIG. 3 is a vertical sectional view taken along line III-III in FIG. 2;

FIG. 4 is a vertical sectional view taken along line IV-IV in FIG. 2;

5 is a vertical cross-sectional view taken along the line VV of FIG.

6 is a view for showing another example of the outer guide used in the push-pull drive device of the present invention, and is a vertical cross-sectional view at a position corresponding to FIG.

FIG. 7 is a side view showing an example in which the push / pull drive device of the present invention is applied to an opening / closing drive device for an extendable hood of a truck bed.

8 is a vertical cross-sectional view taken along the line VIII-VIII in FIG.

FIG. 9 shows a push-pull drive device according to another embodiment of the present invention.
It is a partially expanded side view shown corresponding to.

10 is a vertical cross-sectional view taken along line XX of FIG.

FIG. 11 is a vertical cross-sectional view taken along the line XI-XI of FIG.

FIG. 12 is a vertical cross-sectional view showing another example of the travel guide used in the push-pull drive device of the present invention.

FIG. 13 is a vertical cross-sectional view showing still another example of the travel guide used in the push-pull drive device of the present invention.

FIG. 14 is a side view showing a telescopic hood of a truck bed that has been conventionally considered.

FIG. 15 is a side view showing a push-pull drive device of a reference example using an open end roller chain.

16 is a side view showing an example of a situation when the push-pull drive device shown in FIG. 10 is used.

FIG. 17 is a side view showing another example of the situation when the push-pull drive device shown in FIG. 10 is used.

[Explanation of symbols]

 10 roller chain 12 roller 14 link 16 sprocket 17 storage box 22 object 24 inner guide 26 outer guide 34 cargo bed 36A, 36B side plate 40 hood support

Claims (5)

[Claims] 1. A roller chain formed by connecting a plurality of rollers to each other by a link is made non-annular having an open end, and an object is attached to the tip of the roller chain, and the tip of the roller chain is attached. A device for pushing and pulling the object by advancing and retracting a portion near to a straight or smooth curved predetermined traveling system path, wherein the roller chain is sandwiched from both sides thereof. A straight or smooth curved running guide for guiding the running of the portion of the roller chain along the running path, and for moving the roller chain forward and backward by meshing with the rollers of the roller chain. A driving sprocket that is provided in the vicinity of the base end of the traveling guide and is rotatable in the forward and reverse directions; An inner guide for guiding the roller chain by abutting or facing the link of the roller chain meshing with the sprocket from the side close to the rotation center axis of the sprocket, and the roller meshing with the sprocket near the sprocket. An outer guide for guiding the roller chain by abutting or facing the link or roller of the chain from the side distant from the center axis of rotation of the sprocket, and the inner guide and the outer guide on the traveling guide side. A push-pull drive device using an open-end roller chain, characterized in that the end portion is configured to be parallel to the extension line of the traveling guide. 2. The distance between the tip of the inner guide on the travel guide side and the base end of the travel guide is set to be smaller than the distance between the centers of adjacent rollers of the roller chain. The push-pull drive device using the open-end roller chain described in. 3. The running guide is arranged in a horizontal straight line, the sprocket is arranged so as to have a horizontal center axis of rotation, and the roller chain runs so that the axis of the roller is horizontal. The push-pull drive device according to claim 1, wherein the push-pull drive device is arranged in the. 4. A storage box having an open upper surface is provided below the sprocket to accommodate a portion of a roller chain suspended from the sprocket on a base end side in a folded state. Push-pull drive device with open end roller chain. 5. A device for extending and retracting a telescopic hood that can be telescopically opened and closed by moving a hood column on a cargo bed of a truck along the front-back direction of the cargo bed;
The running guide in the push-pull drive device by the open-end roller chain described in 1 above is horizontally provided along the side plate of the loading platform of the truck at the upper portion thereof, and the lower part of the hood column on the rear end side of the loading platform is the roller chain as the object. An open / close device for a telescopic hood of a truck, which is attached to the tip of the.