Wing opening / closing device

Abstract

To provide a wing opening / closing device that enables an electric actuator to be easily constituted in a small size.SOLUTION: A wing opening / closing device according to the present invention comprises: a frame-side member 15 including a frame-side swing support part 22 swingably supported by being connected to the fixed frame of the loading platform; a wing-side member 16 including a wing-side swing support part 31 swingably supported by being connected to the wing; a screw mechanism 17 including a screw shaft 39 and a nut 40, with the rotary screw element (screw shaft) 39 being supported by one of the members 15 so as to be only rotatable, and with the linear motion screw element (nut) 40 being coupled to the other of the members 16 or integrally formed with the other of the members 16; an electric actuator 20 that rotationally drives the rotary screw element 39; and an urging spring 21 that applies, between the frame-side member 15 and the wing-side member 16, an elastic force in a direction in which an interval between the frame-side swing support portion 22 and the wing-side swing support portion 31 is widened.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a wing opening / closing device for a wing truck.

Background Art

[0002] In a logistics truck, wing trucks configured to be able to load and unload goods from the vehicle width direction with respect to a loading platform having a rectangular box shape are widespread.

[0003] The loading platform of a wing truck is provided with wings in which a roof panel and a side panel are integrated on both sides in the vehicle width direction. The end portion on the center side in the vehicle width direction of the roof panel constituting the wing is connected to a fixed frame that does not rotate or displace with respect to the chassis even when the wing is opened and closed, so as to be able to swing about an axis facing the front-rear direction. A wing opening / closing device is installed between the front end portion and / or the rear end portion of the roof panel constituting the wing and the fixed frame of the loading platform. Based on the expansion and contraction of the wing opening / closing device, the wing swings with respect to the fixed frame of the loading platform, thereby opening and closing the wing.

[0004] Specifically, when the wing opening / closing device extends, the wing swings in the opening direction, and when the wing opening / closing device contracts, the wing swings in the closing direction.

[0005] As the wing opening / closing device, it is common to use a hydraulic cylinder that operates hydraulically. However, when using a hydraulic cylinder, it is necessary to install many devices such as hydraulic piping for supplying hydraulic pressure to the hydraulic cylinder, a hydraulic pump for generating hydraulic pressure, and an electric motor for driving the hydraulic pump, and the wing opening / closing equipment is likely to be enlarged and / or complicated as a whole.

[0006] On the other hand, Japanese Patent Application Laid-Open No. 2014-190436 describes a wing opening / closing device including an electric actuator. The wing opening / closing device described in Japanese Patent Application Laid-Open No. 2014-190436 includes a ball screw mechanism in which a plurality of nuts are screwed onto a screw shaft via a plurality of balls, and an electric actuator including an electric motor and a speed reduction mechanism. By rotationally driving the nut, which is a rotational screw element, via the speed reduction mechanism by the electric motor, the screw shaft, which is a linear screw element, is relatively displaced in the axial direction with respect to the nut, and based on this, it is configured to expand and contract its overall length. By using such a wing opening / closing device, the installation of hydraulic equipment such as hydraulic piping and hydraulic pumps becomes unnecessary, and thus the wing opening / closing equipment can be miniaturized and simplified.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0008] In the conventional wing opening / closing device described in Japanese Patent Application Laid-Open No. 2014-190436, the power for relatively displacing the screw shaft in the axial direction with respect to the nut in order to open and close the wing is significantly larger when swinging the wing in the opening direction against gravity than when swinging the wing in the closing direction where gravity can assist.

[0009] In the conventional wing opening / closing device, since the power for relatively displacing the screw shaft in the axial direction with respect to the nut in order to open the wing is obtained only by the electric actuator including the electric motor and the speed reduction mechanism, there is a problem that the electric actuator is likely to be enlarged.

[0010] An object of the present disclosure is to provide a wing opening / closing device that is easily configured to have a small-sized electric actuator.

Means for Solving the Problem

[0011] The wing opening and closing device according to the first aspect of the present disclosure is a wing opening and closing device used for performing an opening and closing operation of a wing that is swingably supported with respect to a fixed frame on a loading platform of a wing vehicle, a frame side member having a frame side swing support portion swingably supported with respect to the fixed frame, a wing side member having a wing side swing support portion swingably supported with respect to the wing, a screw mechanism including a screw shaft and a nut screwed directly or via a ball to the screw shaft, wherein one of the screw shaft and the nut, which is a rotating screw element, is supported to be rotatable only by one of the frame side member and the wing side member, and the other of the screw shaft and the nut, which is a linear motion screw element, is coupled to the other of the frame side member and the wing side member or is integrally formed with the other member, an electric actuator for rotationally driving the rotating screw element, a biasing spring that imparts an elastic force in a direction to increase the distance between the frame side swing support portion and the wing side swing support portion between the frame side member and the wing side member, and is provided with.

[0012] The wing opening and closing device according to the second aspect of the present disclosure is the wing opening and closing device according to the first aspect of the present disclosure, wherein the biasing spring imparts the elastic force between the frame side member and the wing side member only in a range from a state where the distance is minimum to a state where the distance is intermediate in a range of expansion and contraction of the distance between the frame side swing support portion and the wing side swing support portion.

[0013] The wing opening and closing device according to the third aspect of the present disclosure is the wing opening and closing device according to the first or second aspect of the present disclosure, wherein The rotary screw element is constituted by the screw shaft and is supported inside the one member so as to be rotatable only. The biasing spring is disposed around the screw shaft and inside the one member.

[0014] The wing opening / closing device according to the fourth aspect of the present disclosure is any one of the first to third aspects of the present disclosure. In the wing opening / closing device of any one of the above aspects. The biasing spring is disposed coaxially with the screw shaft.

Advantages of the Invention

[0015] According to the wing opening / closing device of one aspect of the present disclosure, it is easy to configure the electric motor and / or the speed reducer to be small.

Brief Description of the Drawings

[0016]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0017] [First Example] A first example of the embodiment of the present disclosure will be described with reference to FIGS. 1 to 4.

[0018] FIG. 1 shows a wing vehicle 2 incorporating the wing opening / closing device 1 of this example.

[0019] The wing vehicle 2 includes a loading platform 3 having a rectangular box shape in the closed state. The loading platform 3 includes a bottom 4, a front panel 5, a rear frame 6, an upper center frame 7, a pair of rear doors 8, a pair of fender plates 9, a pair of wings 10, and a plurality of wing opening / closing devices 1.

[0020] The bottom 4 has a rectangular flat plate shape extending in the front-rear direction when viewed from above, and constitutes the lower part of the loading platform 3. The bottom 4 is supported and fixed to the upper part of the rear side portion of the chassis 11 of the wing vehicle 2 relative to the cabin 12.

[0021] The front panel 5 has a rectangular flat plate shape when viewed from the front-rear direction, and constitutes the front side portion of the loading platform 3. The lower end portion of the front panel 5 is coupled and fixed to the front end portion of the bottom 4.

[0022] The rear frame 6 has a rectangular frame shape when viewed from the front-rear direction, and constitutes the outer peripheral portion of the rear side portion of the loading platform 3. The lower end portion of the rear frame 6 is coupled and fixed to the rear end portion of the bottom 4.

[0023] The upper central frame 7 has a beam shape extending in the front-rear direction and constitutes the center portion in the vehicle width direction of the upper portion of the loading platform 3. The upper central frame 7 is spanned between the center portion in the vehicle width direction of the upper end portion of the front panel 5 and the center portion in the vehicle width direction of the upper end portion of the rear frame 6. The front end portion of the upper central frame 7 is fixedly coupled to the center portion in the vehicle width direction of the upper end portion of the front panel 5, and the rear end portion of the upper central frame 7 is fixedly coupled to the center portion in the vehicle width direction of the upper end portion of the rear frame 6.

[0024] Among the loading platform 3, the bottom 4, the front panel 5, the rear frame 6, and the upper central frame 7 are fixed frames that do not rotate or displace with respect to the chassis 11 even when the wing 10 is opened and closed for loading and unloading of goods.

[0025] The pair of rear doors 8 constitute the rear side portion of the loading platform 3 together with the rear frame 6. The pair of rear doors 8 are assembled inside the rear frame 6 to enable double-leaf opening and closing.

[0026] The pair of deflector plates 9 constitute the lower side portions on both sides in the vehicle width direction of the loading platform 3. The lower end portion of each deflector plate 9 is connected to the end portion in the vehicle width direction of the bottom 4 so as to be able to swing about an axis facing the front-rear direction. By swinging and displacing each deflector plate 9 outward in the vehicle width direction, the deflector plate 9 can be opened and closed.

[0027] A pair of wings 10 form the upper portions on both sides in the vehicle width direction of the loading platform 3. Each wing 10 is formed by combining a roof panel 13 and a side panel 14 so as to be L-shaped when viewed from the front-rear direction. That is, each wing 10 has, in a closed state, a rectangular plate-shaped roof panel 13 disposed substantially parallel to the bottom 4, and a rectangular plate-shaped side panel 14 bent downward from the end portion on the outer side in the vehicle width direction of the roof panel 13. When the wing 10 is in the closed state, the lower end portion of the side panel 14 abuts or is closely opposed to the upper end portion of the deflector plate 9, or is located outside and below the upper end portion of the deflector plate 9 in the vehicle width direction. Thereby, the internal space of the loading platform 3 is closed. However, in the state where the wing 10 is closed, the lower end portion of the side panel 14 can also be located above the upper end portion of the deflector plate 9.

[0028] The end portion on the center side in the vehicle width direction of the roof panel 13 constituting each wing 10 is connected to the end portion on the outer side in the vehicle width direction of the upper center frame 7 so as to be capable of swinging about a swing axis extending in the front-rear direction. By swinging and displacing each wing 10 in the vertical direction about the swing axis, the opening and closing of the wing 10 can be performed.

[0029] The wing opening / closing device 1 is installed between the front end portion and / or the rear end portion of the roof panel 13 constituting each wing 10 and the fixed frame of the loading platform 3.

[0030] In this example, the wing opening / closing device 1 is installed one by one between the front end portion of the roof panel 13 and the front panel 5 which is the fixed frame, and between the rear end portion of the roof panel 13 and the rear frame 6 which is the fixed frame for each wing 10. That is, in this example, two wing opening / closing devices 1 are installed for each wing 10, and a total of four are installed.

[0031] In addition, in the case of a small wing vehicle or the like where each wing is configured to be relatively lightweight, the wing opening / closing device 1 can also be installed one by one for each wing, for a total of two.

[0032] In addition, in this example, the loading platform 3 is provided with a pair of wings 10 and can be opened and closed on both sides in the vehicle width direction. However, the wing opening / closing device of the present disclosure can also be incorporated into a wing vehicle having a loading platform configured to be openable and closable only on one side in the vehicle width direction, that is, a wing vehicle having only one wing.

[0033] In this example, based on the fact that the two wing opening / closing devices 1 for each wing 10 expand and contract in synchronization with each other, the wing 10 swings around the swing axis with respect to the fixed frame of the loading platform 3, thereby opening and closing the wing 10.

[0034] That is, the wing opening / closing device 1 installed on the front end side of each wing 10 is connected such that the base end portion (frame-side swing support portion 22) in the expansion / contraction direction can swing about an axis oriented in the front-rear direction with respect to the upper end portion of the front panel 5, and the tip end portion (wing-side swing support portion 31) in the expansion / contraction direction can swing about an axis oriented in the front-rear direction with respect to the front end portion of the roof panel 13. Further, the wing opening / closing device 1 installed on the rear end side of each wing 10 is connected such that the base end portion (frame-side swing support portion 22) in the expansion / contraction direction can swing about an axis oriented in the front-rear direction with respect to the upper end portion of the rear frame 6, and the tip end portion (wing-side swing support portion 31) in the expansion / contraction direction can swing about an axis oriented in the front-rear direction with respect to the rear end portion of the roof panel 13. Therefore, when each wing opening / closing device 1 extends, the wing 10 swings in the opening direction, and when each wing opening / closing device 1 contracts, the wing 10 swings in the closing direction.

[0035] In addition, each wing opening / closing device 1 also swings as the wing 10 swings. Specifically, each wing opening / closing device 1 swings in a direction in which the inclination angle of its central axis with respect to the horizontal direction increases as the wing 10 swings in the opening direction, and swings in a direction in which the inclination angle of its central axis with respect to the horizontal direction decreases as the wing 10 swings in the closing direction.

[0036] Hereinafter, the specific structure of each wing opening / closing device 1 will be described.

[0037] The wing opening / closing device 1 includes a frame side member 15, a wing side member 16, a screw mechanism 17, an electric actuator 20 composed of an electric motor 18 and a speed reduction mechanism 19, and a biasing spring 21.

[0038] Regarding the wing opening / closing device 1, unless otherwise specified, the axial direction, circumferential direction, and radial direction refer to the axial direction, circumferential direction, and radial direction of the screw shaft 39 and the nut 40 constituting the screw mechanism 17. The axial direction, circumferential direction, and radial direction of the screw shaft 39 and the nut 40 coincide with the axial direction, circumferential direction, and radial direction of the cylinder portion 23 of the frame side member 15, and also coincide with the axial direction, circumferential direction, and radial direction of the wing side member 16. In this example, with respect to the axial direction, one side refers to the right side in FIGS. 2 to 4, and the other side with respect to the axial direction refers to the left side in FIGS. 2 to 4.

[0039] The frame side member 15 has a frame side swing support portion 22 that is swingably supported (connected) with respect to the fixed frame of the loading platform 3.

[0040] In this example, in addition to the frame side swing support portion 22, the frame side member 15 has a cylinder portion 23 and a base portion 24.

[0041] The cylinder portion 23 serves as a housing portion for the screw mechanism 17. The cylinder portion 23 has a cylindrical cylinder large diameter cylinder portion 25 that constitutes most of it, a hollow circular plate-shaped cylinder step portion 26 that bends radially inward from one end on the axial direction side of the cylinder large diameter cylinder portion 25, and a cylindrical cylinder small diameter cylinder portion 27 that extends axially from the end on the radially inner side of the cylinder step portion 26 toward one side in the axial direction.

[0042] The base portion 24 serves as a housing portion for the speed reduction mechanism 19 and is connected to the end portion on the other axial side of the cylinder portion 23. The base portion 24 has a cylinder connection portion 28 (the lower side portion in FIGS. 2 to 4) disposed at a position axially overlapping the cylinder portion 23, and an overhanging portion 29 (the upper side portion in FIGS. 2 to 4) that projects radially outward of the cylinder portion 23 with respect to the cylinder connection portion 28.

[0043] The frame-side swing support portion 22 is provided so as to project axially to the other axial side from the side surface on the other axial side of the cylinder connection portion 28 of the base portion 24. The frame-side swing support portion 22 is constituted by a substantially rectangular flat plate-shaped bracket, and has a frame-side insertion hole 30 at its tip end portion. The frame-side swing support portion 22 is swingably connected to the fixed frame by inserting an axially oriented shaft-like member such as a bolt supported by the fixed frame of the loading platform 3 (the upper end portion of the front panel 5 or the upper end portion of the rear frame 6) into the frame-side insertion hole 30.

[0044] The wing-side member 16 has a wing-side swing support portion 31 that is swingably supported (connected) with respect to the wing 10.

[0045] In this example, the wing-side member 16 functions as a piston coaxially fitted to the cylinder portion 23. The wing-side member 16 has a piston portion 32 in addition to the wing-side swing support portion 31.

[0046] The piston portion 32 has a cylindrical piston large-diameter cylinder portion 33, a hollow circular plate-shaped piston stepped plate portion 34 that bends radially inward from the end portion on one axial side of the piston large-diameter cylinder portion 33, a cylindrical piston small-diameter cylinder portion 35 that extends axially from the end portion on the radially inner side of the piston stepped plate portion 34, and a piston bottom portion 36 that closes the opening at the end portion on one axial side of the piston small-diameter cylinder portion 35.

[0047] The piston large-diameter cylinder portion 33 is disposed inside the cylinder large-diameter cylinder portion 25. The outer diameter of the piston large-diameter cylinder portion 33 is larger than the inner diameter of the cylinder small-diameter cylinder portion 27 and slightly smaller than the inner diameter of the cylinder large-diameter cylinder portion 25.

[0048] The small-diameter piston cylinder part 35 is inserted into the small-diameter cylinder part 27. A cylindrical bush 37 is fitted and fixed inside the small-diameter cylinder part 27. The bush 37 has functions as a sliding bearing and a sealing member, and its inner peripheral surface is in sliding contact with the outer peripheral surface of the small-diameter piston cylinder part 35.

[0049] The wing-side swing support part 31 is provided so as to protrude from the central part of the piston bottom part 36 toward one side in the axial direction. The wing-side swing support part 31 is constituted by a substantially rectangular flat plate-shaped bracket, and has a wing-side insertion hole 38 at its tip. The wing-side swing support part 31 is swingably connected to the wing 10 by inserting an axially oriented shaft-like member such as a bolt supported at the front end part or the rear end part of the roof panel 13 constituting the wing 10 into the wing-side insertion hole 38.

[0050] In this example, the piston part 32 of the wing-side member 16 is displaced relative to the cylinder part 23 of the frame-side member 15 in the axial direction, whereby the wing opening / closing device 1 expands and contracts in the axial direction.

[0051] The screw mechanism 17 includes a screw shaft 39 and a nut 40 screwed onto the screw shaft 39. As the screw shaft 39 and the nut 40 rotate relative to each other, the screw shaft 39 and the nut 40 are displaced relative to each other in the axial direction.

[0052] In this example, the screw mechanism 17 further includes a plurality of balls 41, and the nut 40 is screwed onto the screw shaft 39 via the plurality of balls 41. That is, in this example, the screw mechanism 17 is constituted by a ball screw mechanism. However, when implementing the present disclosure, the screw mechanism can also be constituted by a sliding screw mechanism in which the nut is directly screwed onto the screw shaft.

[0053] In this example, the screw shaft 39 has a shaft-side ball screw groove 42 on the outer peripheral surface of the axial intermediate portion. The nut 40 has a nut-side ball screw groove 43 on the inner peripheral surface. The screw shaft 39 is arranged coaxially with the nut 40 with the axial intermediate portion inserted radially inside the nut 40. A spiral load path formed by the shaft-side ball screw groove 42 and the nut-side ball screw groove 43 is provided between the outer peripheral surface of the screw shaft 39 and the inner peripheral surface of the nut 40. A plurality of balls 41 are rotatably arranged in the load path. Thus, based on the relative rotation of the screw shaft 39 and the nut 40, the screw shaft 39 and the nut 40 can be relatively displaced in the axial direction.

[0054] Note that when the screw shaft 39 and the nut 40 are relatively rotated, the balls 41 that have reached the end point of the load path are returned to the start point of the load path through a circulation path (not shown) provided in the nut 40.

[0055] In this example, the screw shaft 39 constitutes a rotary screw element that is supported by the frame side member 15 so as to be rotatable only, and the nut 40 constitutes a linear motion screw element coupled to the wing side member 16.

[0056] Specifically, the screw shaft 39 is arranged coaxially with the cylinder portion 23 and the piston portion 32 inside the cylinder portion 23, the piston portion 32, and the base portion 24 of the frame side member 15. One end portion on the other axial side where the shaft-side ball screw groove 42 is not formed of the screw shaft 39 is supported by a pair of rolling bearings 44 and 45 arranged axially spaced apart from the base portion 24 so as to be rotatable only.

[0057] Furthermore, a cylindrical bush 46 is externally fitted and fixed to one end portion on the axial side of the screw shaft 39 where the shaft-side ball screw groove 42 is not formed. The bush 46 has functions as a stopper and a retaining member when the nut 40 is displaced to the vicinity of one end portion on the axial side of the screw shaft 39, and its outer peripheral surface is in sliding contact with the inner peripheral surface of the piston small-diameter cylindrical portion 35.

[0058] The nut 40 is fitted and fixed inside the piston large-diameter cylinder portion 33 of the wing side member 16.

[0059] The electric actuator 20 rotationally drives a screw shaft 39 which is a rotary screw element. In this example, the electric actuator 20 has an electric motor 18 and a speed reduction mechanism 19, and the electric motor 18 rotationally drives the screw shaft 39 via the speed reduction mechanism 19.

[0060] In this example, the electric motor 18 is supported by the frame side member 15. Specifically, the electric motor 18 is disposed at a position adjacent in the radial direction to the other end in the axial direction of the cylinder portion 23, and is coupled and fixed to the overhanging portion 29 of the base portion 24. The output shaft 47 of the electric motor 18 is disposed parallel to the screw shaft 39 and the nut 40, and the tip thereof is inserted inside the cylinder connection portion 28 of the base portion 24.

[0061] The speed reduction mechanism 19 is disposed between the electric motor 18 and the screw shaft 39, increases the output torque of the electric motor 18, and then transmits it to the screw shaft 39.

[0062] That is, in the wing opening and closing device 1 of this example, the screw shaft 39 is rotated by transmitting the output torque of the electric motor 18 to the screw shaft 39 via the speed reduction mechanism 19. Thereby, based on the relative displacement of the nut 40 in the axial direction with respect to the screw shaft 39, the piston portion 32 of the wing side member 16 is relatively displaced in the axial direction with respect to the cylinder portion 23 of the frame side member 15, so that the wing opening and closing device 1 expands and contracts in the axial direction.

[0063] In this example, the speed reduction mechanism 19 is constituted by a gear type speed reduction mechanism and is housed in the base portion 24 of the frame side member 15.

[0064] The speed reduction mechanism 19 includes a first gear 48, a second gear 49, a third gear 50, and a fourth gear 51. The first gear 48 is supported and fixed to the tip of the output shaft 47 of the electric motor 18. The second gear 49 and the third gear 50 are supported and fixed to an intermediate shaft that is supported inside the base portion 24 parallel to the screw shaft 39 and only allowed to rotate. The second gear 49 has a larger number of teeth than the first gear 48, and the teeth of the second gear 49 mesh with the teeth of the first gear 48. The third gear 50 has a smaller number of teeth than the second gear 49. The fourth gear 51 is supported and fixed to the other end of the screw shaft 39 in the axial direction. The fourth gear 51 has a larger number of teeth than the third gear 50, and the teeth of the fourth gear 51 mesh with the teeth of the third gear 50.

[0065] The wing opening and closing device 1 of this example further includes an electromagnetic brake 61 assembled to the output shaft 47. The electromagnetic brake 61 is housed in the base portion 24.

[0066] When the electric motor 18 operates, the electromagnetic brake 61 is energized and switched to a non-locked state that allows the rotation of the output shaft 47 and the rotation of the speed reduction mechanism 19 (the rotation of the first gear 48, the second gear 49, the third gear 50, and the fourth gear 51). Thereby, torque can be transmitted from the electric motor 18 to the screw mechanism 17 via the speed reduction mechanism 19, that is, the wing opening and closing device 1 can be expanded and contracted in the axial direction to perform the opening and closing operation of the wing 10.

[0067] On the other hand, when the energization to the electromagnetic brake 61 is cut off when the electric motor 18 is not operating, it switches to a locked state where the rotation of the output shaft 47 and the rotation of the speed reduction mechanism 19 are blocked. In the locked state, even when torque due to the self-weight of the wing 10 is reversely input from the side of the wing 10, the speed reduction mechanism 19 does not rotate. Therefore, according to the wing opening / closing device 1 of this example, the state in which the wing 10 is open can be maintained without operating the electric motor 18. When implementing the present disclosure, the electromagnetic brake 61 can also be assembled to the speed reduction mechanism 19. However, from the viewpoint of, for example, keeping the braking force for realizing the locked state small, it is preferable to assemble the electromagnetic brake 61 to the output shaft 47 as in this example.

[0068] When implementing the present disclosure, as the speed reduction mechanism, not limited to a gear type speed reduction mechanism, a belt type or a chain type speed reduction mechanism can also be adopted. Also, when implementing the present disclosure, if various speed reduction mechanisms such as a worm speed reduction mechanism having a self-locking function are used as the speed reduction mechanism, the torque reversely input from the side of the wing can be blocked by the speed reduction mechanism having the self-locking function. Therefore, the state in which the wing is open can be maintained without using an electromagnetic brake.

[0069] The biasing spring 21 applies an elastic force in a direction in which the distance between the frame side swing support portion 22 and the wing side swing support portion 31 expands, that is, in a direction in which the wing opening / closing device 1 extends in the axial direction, between the frame side member 15 and the wing side member 16.

[0070] When implementing the present disclosure, the biasing spring can be configured by using one or a plurality of various springs such as a coil spring, a leaf spring, and a disc spring. In this example, the biasing spring 21 is configured by one coil spring.

[0071] In this example, the biasing spring 21 is disposed around the screw shaft 39 and inside the frame side member 15. In other words, the biasing spring 21 is disposed between the screw shaft 39 and the frame side member 15 in the radial direction. Thereby, protection of the biasing spring 21 is achieved. Specifically, the biasing spring 21 is coaxially disposed around the screw shaft 39 and inside the cylinder portion 23 of the frame side member 15. In the wing opening and closing device 1 of this example, since the biasing spring 21 is disposed coaxially with the screw shaft 39, it is easy to configure the wing opening and closing device 1 to be small. However, when implementing the present disclosure, the biasing spring 21 can also be disposed in parallel with the screw shaft 39.

[0072] More specifically, the biasing spring 21 is disposed between the side surface 52 on one axial side of the cylinder connection portion 28 of the base portion 24 and the side surface 53 on the other axial side of the combined body of the nut 40 and the piston large-diameter cylinder portion 33.

[0073] As shown in FIG. 2, the biasing spring 21 is elastically biased against the frame side member 15 in the direction in which the wing opening and closing device 1 extends in the axial direction based on its elastic restoring force while being axially compressed between the side surface 52 and the side surface 53.

[0074] Therefore, in a state where such a biasing force is generated, the torque transmitted from the electric motor 18 and the speed reduction mechanism 19 to the screw mechanism 17, which is required to extend the wing opening and closing device 1 in the axial direction by an amount corresponding to the biasing force, can be reduced.

[0075] Incidentally, the wing opening / closing device 1 in this example swings as the wing 10 opens and closes, and the inclination angle of the central axis of the wing opening / closing device 1 (the central axis of the screw shaft 39) with respect to the horizontal direction is the smallest when the wing 10 is fully closed (for example, about 15°). Also, when opening the wing 10, the force with which the wing opening / closing device 1 presses the wing 10 has a small vertical component and is difficult to be reflected as a force for opening the wing 10 while the inclination angle is small. For this reason, the driving force of the wing opening / closing device 1 required to open the wing 10, specifically the output torque of the electric motor 18, becomes larger in the range where the inclination angle is small compared to the range where the inclination angle is large. That is, the driving force of the wing opening / closing device 1 is the largest when opening the wing 10 from the fully closed state.

[0076] Therefore, in this example, a configuration is adopted in which an elastic force by the biasing spring 21 is applied between the frame side member 15 and the wing side member 16 only in a range where the driving force of the wing opening / closing device 1 required to open the wing 10 is relatively large.

[0077] Specifically, only in the range from the state where the interval is the smallest (the state shown in FIG. 2) to the intermediate state (the state shown in FIG. 3) in the expansion and contraction range of the interval between the frame side swing support portion 22 and the wing side swing support portion 31 during use of the wing opening / closing device 1, a configuration is adopted in which the biasing spring 21 elastically biases the wing side member 16 with respect to the frame side member 15.

[0078] More specifically, the axial length Lf of the biasing spring 21 in the free state is set to a value smaller than the axial interval W between the side surface 52 and the side surface 53 in the state where the interval between the frame side swing support portion 22 and the wing side swing support portion 31 during use of the wing opening / closing device 1 is the largest (the state shown in FIG. 4), that is, when the wing 10 is fully open (Lf < W). When implementing the present disclosure, the ratio of the axial length Lf to the axial interval W can be set to any size, but in this example, the ratio is set to 50% or less, specifically about 30%.

[0079] In this example, among the expansion and contraction ranges of the distance between the frame-side swing support portion 22 and the wing-side swing support portion 31 during the use of the wing opening and closing device 1, only in the range from the state where the distance is the smallest to the intermediate state, since the biasing spring 21 is configured to apply an elastic force between the frame-side member 15 and the wing-side member 16, the biasing spring 21 can be made small. Therefore, accordingly, the component cost of the biasing spring 21 can be suppressed. However, when implementing the present disclosure, it is also possible to adopt a configuration in which an elastic force by a biasing spring is applied between the frame-side member and the wing-side member throughout the expansion and contraction range of the distance between the frame-side swing support portion and the wing-side swing support portion during the use of the wing opening and closing device.

[0080] As described above, in this example, in the range where the driving force of the wing opening and closing device 1 required to open the wing 10 is relatively large, the torque applied to the screw shaft 39 of the screw mechanism 17 by the electric actuator 20 required to extend the wing opening and closing device 1 in the axial direction can be reduced according to the elastic biasing force (support force) by the biasing spring 21. Therefore, accordingly, it becomes possible to miniaturize the electric motor 18 and / or the reduction mechanism 19.

[0081] Note that the elastic biasing force (support force) by the biasing spring 21 can be set to any magnitude, but the biasing force should be set to a magnitude within the range where the biasing spring 21 can be compressed by the self-weight of the wing 10 when closing the wing 10.

[0082] [Second Example] A second example of the embodiment of the present disclosure will be described with reference to FIGS. 5 and 6.

[0083] In the wing opening and closing device 1a of this example, the wing opening and closing device 1a is configured to expand and contract in the axial direction based on the relative displacement of the screw shaft 39a in the axial direction with respect to the nut 40a by rotationally driving the nut 40a by the electric actuator 20a. That is, in this example, the nut 40a constitutes a rotary screw element, and the screw shaft 39a constitutes a linear motion screw element.

[0084] In this example, the cylinder part 23a that constitutes the frame side member 15a includes a substantially cylindrical cylinder large-diameter cylinder part 25a located at one end in the axial direction, a substantially hollow circular plate-shaped cylinder step part 26a that bends radially inward from the other end in the axial direction of the cylinder large-diameter cylinder part 25a, a cylindrical cylinder small-diameter cylinder part 27a that extends from the inner end in the radial direction of the cylinder step part 26a toward the other end in the axial direction, and a cylinder bottom part 54 that closes the opening at the other end in the axial direction of the cylinder small-diameter cylinder part 27a.

[0085] In this example, in the base part 24a that constitutes the frame side member 15a, the cylinder connection part 28 is connected to one end in the axial direction of the cylinder part 23a.

[0086] In this example, the frame side swing support part 22 that constitutes the frame side member 15a is provided so as to protrude toward the other end in the axial direction from the side surface on the other end in the axial direction of the cylinder bottom part 54.

[0087] In this example, the nut 40a that constitutes the screw mechanism 17a is supported inside the cylinder large-diameter cylinder part 25a by a pair of rolling bearings 55 arranged axially apart so as to be rotatable only.

[0088] In this example, one end in the axial direction of the screw shaft 39a that constitutes the screw mechanism 17a protrudes outside the base part 24a through a through hole 56 provided in the cylinder connection part 28 of the base part 24a.

[0089] In this example, the wing side member 16a has a receiving plate 57 in addition to the wing side swing support part 31. The receiving plate 57 is configured in a substantially disc shape and has an outer diameter larger than the outer diameter of the screw shaft 39a. The receiving plate 57 is fixed coaxially with the screw shaft 39a to one end in the axial direction of the screw shaft 39a. The wing side swing support part 31 is provided so as to protrude toward one end in the axial direction from the central part of the receiving plate 57.

[0090] In this example, the electric motor 18 is disposed at a position adjacent in the radial direction to one axial end of the cylinder portion 23a and is fixedly coupled to the overhanging portion 29 of the base portion 24a.

[0091] In this example, the fourth gear 51a constituting the speed reduction mechanism 19a is fixed coaxially with the nut 40a to one axial end face of the nut 40a and has a central hole 58 through which the screw shaft 39a is inserted at the central portion in the radial direction.

[0092] In this example, the biasing spring 21 is disposed coaxially with the screw shaft 39a around the screw shaft 39a in a portion located on one axial side of the base portion 24a, and is disposed between the side face 59 on one axial side of the cylinder connection portion 28 of the base portion 24a and the side face 60 on the other axial side of the receiving plate 57. In the wing opening / closing device 1a of this example, since the biasing spring 21 is disposed coaxially with the screw shaft 39a, it is easy to configure the wing opening / closing device 1a to be small. However, when implementing the present disclosure, the biasing spring 21 can also be disposed in parallel with the screw shaft 39a.

[0093] As shown in FIG. 5, the biasing spring 21 is axially compressed between the side face 59 and the side face 60, and elastically biases the wing side member 16a with respect to the frame side member 15a in the direction in which the wing opening / closing device 1a extends axially based on its own elastic restoring force.

[0094] Therefore, also in the case of this example, in a state where such a biasing force is generated, the torque applied to the nut 40a of the screw mechanism 17a by the electric actuator 20a, which is required to axially extend the wing opening / closing device 1a by an amount corresponding to the biasing force, can be reduced.

[0095] Also in the case of this example, a configuration is adopted in which an elastic force by the biasing spring 21 is applied between the frame side member 15a and the wing side member 16a only in a range where the driving force of the wing opening / closing device 1a required to open the wing 10 is relatively large.

[0096] Specifically, the axial length Lf of the biasing spring 21 in its free state is set to a value smaller than the axial distance W between the side surface 59 and the side surface 60 in a state where the distance between the frame-side swing support portion 22 and the wing-side swing support portion 31 is maximum during the use of the wing opening / closing device 1a (the state shown in FIG. 6) (Lf < W).

[0097] The other configurations, operations, and effects of the second example are the same as those of the first example.

[0098] When implementing the present disclosure, a configuration in which a screw shaft (rotating screw element) is supported by the wing-side member so as to be rotatable only, and a nut (linear motion screw element) is coupled to the frame-side member, or a configuration in which a nut (rotating screw element) is supported by the wing-side member so as to be rotatable only, and a screw shaft (linear motion screw element) is coupled to the frame-side member can also be adopted. Further, the linear motion screw element and the wing-side member or the frame-side member can be integrally configured.

Explanation of Reference Numerals

[0099] 1, 1a Wing opening / closing device 2 Wing vehicle 3 Loading platform 4 Bottom 5 Front panel 6 Rear frame 7 Upper central frame 8 Rear door 9 Deflector 10 Wing 11 Chassis 12 Cabin 13 Roof panel 14 Side panel 15, 15a Frame-side member 16, 16a Wing-side member 17, 17a Screw mechanism 18 Electric motor 19, 19a Speed reduction mechanism 20, 20a Electric actuator 21 Biasing spring 22 Frame-side swing support portion 23, 23a Cylinder part 24, 24a Base part 25, 25a Large-diameter cylinder part 26, 26a Cylinder step part 27, 27a Small-diameter cylinder part 28 Cylinder connection part 29 Protruding part 30 Frame-side insertion hole 31 Wing-side swing support part 32 Piston part 33 Large-diameter piston cylinder part 34 Piston step part 35 Small-diameter piston cylinder part 36 Piston bottom part 37 Bush 38 Wing-side insertion hole 39, 39a Screw shaft 40, 40a Nut 41 Ball 42 Shaft-side ball screw groove 43 Nut-side ball screw groove 44 Rolling bearing 45 Rolling bearing 46 Bush 47 Output shaft 48 First gear 49 Second gear 50 Third gear 51, 51a Fourth gear 52 Side surface 53 Side surface 54 Cylinder bottom 55 Rolling bearing 56 Through hole 57 Receiving plate 58 Central hole 59 Side surface 60 Side surface 61 Electromagnetic brake

Claims

1. A wing opening / closing device used for performing the opening / closing operation of a wing swingably supported with respect to a fixed frame on a loading platform of a wing vehicle, comprising: a frame-side member having a frame-side swing support portion swingably supported with respect to the fixed frame; a wing-side member having a wing-side swing support portion swingably supported with respect to the wing; a screw mechanism including a screw shaft and a nut screwed directly or via balls to the screw shaft, wherein one of the screw shaft and the nut, which is a rotating screw element, is supported by one of the frame-side member and the wing-side member so as to be rotatable only, and the other of the screw shaft and the nut, which is a linear motion screw element, is coupled to the other of the frame-side member and the wing-side member or is integrally formed with the other member; an electric actuator for rotationally driving the rotating screw element; a biasing spring for applying an elastic force in a direction to increase the distance between the frame-side swing support portion and the wing-side swing support portion between the frame-side member and the wing-side member; and a wing opening / closing device.

2. The wing opening / closing device according to claim 1, wherein the biasing spring applies the elastic force between the frame-side member and the wing-side member only in a range from a state where the distance between the frame-side swing support portion and the wing-side swing support portion is minimum to a state where the distance is intermediate within an expansion / contraction range of the distance between the frame-side swing support portion and the wing-side swing support portion.

3. The rotating screw element is constituted by the screw shaft and is supported by the inside of the one member so as to be rotatable only, and the biasing spring is disposed around the screw shaft and inside the one member. The wing opening / closing device according to claim 1.

4. The wing opening / closing device according to claim 1, wherein the biasing spring is disposed coaxially with the screw shaft. The wing opening / closing device according to claim 1.

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