JPH11147456A - Trailer braking system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a trailer braking system, wherein the switching between operation/non-operation of the system is prevented even if the trailer advances while it is retreating, and that allows an easy switching of the operation/non- operation. SOLUTION: This trailer T braking system 51, provided with a freely advancing are retracting hitch rod 3 connected to a tractor, brakes the trailer by actuating the brake by a shrinking and retreating movement of the hitch rod 3 against the trailer when the tractor stops. This trailer T braking system 51 comprises a switching means 9 that detachably and movably supports a stopper member 31 which is engaged with the body of the trailer at the extending position of the hitch rod 3 and controls the shrinkage and retreating of the hitch rod 3. The switching means 9 is operated from the tractor using wires or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brake system for a trailer in which the inertial force of a trailer body which tries to plunge into the tow vehicle when braking and decelerating the tow vehicle is used as a brake operating force. The present invention relates to a device capable of switching between operation and non-operation.

[0002]

2. Description of the Related Art A trailer connected to a tow vehicle tends to rush toward the tow vehicle due to the braking and deceleration of the tow vehicle, and a compressive force is applied to the connection portion by the inertia force of the trailer. Some trailers are provided with an inertial braking device that operates a brake using this compression force, and various systems have been devised. For example, a trailer braking device (inertia brake) disclosed in Japanese Utility Model Laid-Open Publication No. 47-13834 is one of them.

[0003] As shown in FIG.
A drawbar pipe 62 provided at the front end of the trailer body 61 and a coupler 6 connected to a towing vehicle (not shown)
3 is drawn forward and the drawbar 64 is inserted into the drawbar pipe 62 so as to be able to advance and retreat.
2, a shock absorbing means 65 for absorbing a shock applied to the draw bar 64. When the draw bar 64 is retracted into the draw bar pipe 62, a lever 66 interlocked with the brake is pushed to the traveling wheel (not shown). The brakes are activated.

When the towing vehicle applies light braking or engine braking, the amount of movement is limited while absorbing the inertial force by the shock absorbing means, so that the brake is not dragged to cause fade or the like.

[0005] The braking device 60 is provided with switching means 67 for preventing the braking device from operating when the towing vehicle and the trailer move backward.

The switching means 67 includes a switching lever 68 rotatably provided on the drawbar pipe 62 and a switching lever 6.
A torsion spring 69 provided between the drawbar 8 and the drawbar pipe 62 to elastically urge the tip of the lever toward the rear;
And a bracket 70 fixed to the coupler 63 for inserting the tip of the switching lever 68. The switching lever 68 is rotated against the urging force of the torsion spring 69, and the switching lever 6
8 By inserting the tip into the bracket 70, the drawbar 6
4 is to be restricted.

When moving backward, the switching lever 68
Is half-turned and inserted into the bracket 70, the operation of the braking device 60 is released, and the vehicle can move backward without applying the brake.

[0008]

However, when the brake device 60 is released and the vehicle is moving backward while the vehicle is moving backward without applying the brake, it is necessary to temporarily move forward, for example, by turning back. However, the torsion spring 69 automatically turns off the bracket 70 and turns, and the braking device 60 is activated. In this case, it is necessary to once get off the towing vehicle, to engage the switching lever 68 with the bracket 70 again to release the operation of the braking device 60, which requires an extra operation to reverse again, which is complicated. There is a problem that there is.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to solve the above-mentioned problems and to prevent switching between operation and non-operation of a braking device even when the vehicle travels in reverse and easily switch between operation and non-operation. It is an object of the present invention to provide a brake device for a trailer which can be operated.

[0010]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a trailer body which is provided with a hitch rod connected to a towing vehicle so as to be extendable and retractable. In the trailer braking device that operates the brake by the retracting movement of the trailer to brake the trailer, a stopper member that engages with the trailer body at the extended position of the hitch rod to regulate the contraction of the hitch rod is movably supported. Switching means, and the switching means is operated from the towing vehicle side by a wire or the like.

[0011] Further, the hitch rod has a protruding portion at the tip thereof,
A stopper member is interposed between the protrusion and the trailer body to engage and restrict the retraction of the hitch rod, and the switching means is provided by a lever member which rotates to move the engagement position and the disengagement position of the stopper member. That is, the lever member may be operated from the towing vehicle side with a wire or the like.

Further, the lever member is urged to rotate in one direction by a spring, and the lever member is provided with a click mechanism for holding a rotation position of engagement and disengagement. The engagement position may be alternately repeated.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIGS. 1 and 5, the trailer T
Is a trailer body 50 having freely rotating traveling wheels 5 and 6, a hitch rod 3 connecting the trailer body 50 to a towing vehicle (not shown), and braking of the trailer T when the towing vehicle is braked. And a braking device 51 that performs the braking operation.

The trailer body 50 has an axle 4a fixed to the machine frame 1 via a bracket 4, and running wheels 5 and 6 are rotatably provided on the axle 4a. Extend forward in the traveling direction and are connected.

The machine frame 1 is a pair of parallel vertical frames 1c extending in the vehicle length direction, a rectangular frame 1a fixed on the vertical frame 1c to form an outer shell, and is stretched over the rectangular frame 1a in the machine width direction. And a fixed horizontal rod 1b. A floor plate 41 is laid on the machine frame 1.

The traveling wheels 5 and 6 are arranged in a row in the vicinity of the center of the trailer body 50 in the front-rear direction, and are disposed outside the traveling wheels 6 on the both sides in the machine width direction. And inner running wheels 5 to be formed.

As shown in FIGS. 1 and 2, the towing frame 2 is
A symmetrical frame member 2a, 2b is provided to be narrowed toward the center of the front end. A tubular body 10 for slidably supporting the hitch rod 3 is opened in the front end of the towing frame 2 in the front-rear direction. It is provided facing. A stand 7 is provided on the frame member 2a that forms the right side of the towing frame 2 in the traveling direction.

As shown in FIG. 2 and FIG.
Is slidably inserted into the cylindrical body 10 so as to be movable with respect to the trailer body 50 so as to be able to extend and retract.

A contact ring (protrusion) 3a for restricting the contraction of the hitch rod 3 is fixed to a front portion of the hitch rod 3 extending forward of the cylindrical body 10. The locking cylinder 11 for restricting the extension of the hitch rod 3 is a bolt 1
2 firmly fixed.

At the front of the hitch rod 3, there is disposed a sliding cylinder 13 which is slidably movable between the cylinder 10 and the contact ring 3a. Between them, a gas spring 14 for hitting the contracting hitch rod 3 and slowing down the contracting speed of the hitch rod 3 is provided via the protruding pieces 10a and 13a.

The braking device 51 operates the brake by the retracting movement of the hitch rod 3 with respect to the trailer body 50 in response to the stop of the towing vehicle, and brakes the trailer T. The vehicle includes a brake actuating device 8 for operating a brake device 5a mounted on the traveling wheel 5, and a switching device (switching means) 9 for fixing the brake operating device 8 to a non-operating state.

As shown in FIGS. 2, 3, 4 and 5,
The brake actuating device 8 includes a pivoting member 16 that pivots when the hitch rod 3 is retracted, and an actuation force transmission system 53 that is connected to the pivoting member 16 and that transmits a braking actuation force to a brake device 5a described later. Become.

The rotating member 16 is formed in an L shape, with one end directed in the machine width direction and the other end directed downward.
It is attached via a bracket 15 and bolts 45 to a frame member 2b located on the left side in the traveling direction of the towing frame 2 so as to be rotatable around a horizontal axis. Also, one end 1 of the rotating member 16
6 a is in contact with the rear end of the hitch rod 3, and an operating force transmission system 53 is connected to the other end 16 b of the rotating member 16.

As shown in FIGS. 3, 4, and 5, the operating force transmission system 53 is connected to the other end 16b of the rotating member 16 so as to be rotatable and extends rearward. A second connecting member 18 connected to the first connecting member 17, a third connecting member 20 and a fourth connecting member 21 branched from the second connecting member 18 in the machine width direction, and a third connecting member 20; And a fifth connecting member 24 connected to the brake device 5a of the inner traveling wheel 5 on the right side when viewed from the bottom, and a brake device 5a for the inner traveling wheel 5 connected to the fourth connecting member 21 and on the left side when viewed from the bottom. And a sixth connection member 25 connected to the second connection member.

The first connecting member 17 fixes the front end of the rod 17a to a plate 17b connected to the rotating member 16, and fixes the fork end 17d connected to the second connecting member 18 to the rear end of the rod 17a. It is. Plate 17b
Has a long hole 1 through which a bolt 17e is slidably inserted.
7c is formed. The fork end 17d has a screw hole, and the rod 17a is screwed into the screw hole so that the rod 1
7a.

The second connecting member 18 is formed in a substantially V-shape in plan view, and has a top 18a rotatably connected to a fork end 17d via a pin 19. Pins 18d and 18e are fixed laterally to left and right ends 18b and 18c of the second connecting member 18 branched in the machine width direction.
A third connecting member 20 and a fourth connecting member 21 are rotatably and loosely connected to d and 18e, respectively.

The second connecting member 18 is provided with a tension spring 3 which elastically urges the second connecting member 18 to pull backward.
9 is provided, and one end is provided on the top 1 of the second connecting member 18.
8a, and the other end is locked to an upright pin of a fixed piece 40 provided hanging down from the machine frame 1.

The third connecting member 20 has one end rotatably inserted into a pipe 22 fixed to the right side of the bottom of the machine frame 1 when viewed from the bottom, and the other end connected to a pipe 23 fixed near the center of the machine frame 1.
A first support rod 20a rotatably inserted into the first support rod 20a, and a first central protrusion 20 fixed to the first support rod 20a and extending downward.
b and the first support rod 20a in parallel with the first center side projection 20b.
And a left protruding piece 20c fixed to A pin 18d is inserted through and locked to the first central protruding piece 20b.
The center protruding piece 20b and the second connecting member 18 are rotatably connected via a pin 18d. The pipe 23 is a plate 2
It is fastened to the machine frame 1 via 3a.

The fourth connecting member 21 has one end rotatably inserted into a pipe 22 fixed to the left side of the machine frame 1 as viewed from the bottom, and the other end connected to a pipe 23 fixed near the center of the machine frame 1.
A second support rod 21a rotatably inserted into the second support rod 21a, and a second central protrusion 21 fixed to the second support rod 21a and extending downward.
b and the second support rod 21a in parallel with the second central side protruding piece 21b.
And right side projection 21c fixed to A pin 18e is inserted through and locked to the second center-side projecting piece 21b.
The center protruding piece 21b and the second connecting member 18 are rotatably connected via a pin 18e.

The fifth connecting member 24 and the sixth connecting member 25 are
Each is formed in a rod shape.

The fifth connecting member 24 is disposed on the right side when viewed from the bottom, one end of which is rotatably connected to the left projecting piece 20c of the third connecting member 20, and the other end is located on the right side when viewed from the bottom. It is connected to an operation lever 5b of a brake device 5a mounted on the wheel 5.

The sixth connecting member 25 is disposed on the left side when viewed from the bottom, one end of which is rotatably connected to the right protruding piece 21c of the fourth connecting member 21, and the other end is located on the left side when viewed from the bottom. It is connected to an operation lever 5b of a brake device 5a mounted on the wheel 5.

As shown in FIGS. 2 and 3, the switching device 9
Is a locking lever (lever member) formed in a substantially L-shaped plate shape
Consists of 28.

The locking lever 28 is rotatably connected via a bolt 29 to a support piece 27 provided with its bent portion 52 standing on the upper surface of the front end of the towing frame 2 and has a relatively short length forward. The short side 28b is extended, and the long side 28e having a relatively long length is extended rearward.

At the end of the short side 28b, a stopper member 31 is provided via a flat plate 28c and a bolt 30 so as to be retractable. The flat plate 28c is fixed to the end of the short side 28b so that the plate surface is substantially horizontal when the locking lever 28 is rotated forward, and the bolts 30 are set on the left and right sides of the short side 28b, respectively. Is extended downward.

The stopper member 31 is engaged at the extended position of the hitch rod 3 to regulate the contraction of the hitch rod 3, and a nut 30a is integrally fixed to the upper part of the stopper member 31. The tip of a bolt 30 is screwed to the nut 30a, and the stopper member 31 and the bolt 30 are integrally fixed.

A spring 32 is disposed between the stopper member 31 and the flat plate 28c to elastically bias the stopper member 31 in a direction (downward) away from the flat plate 28c. By rotating the locking lever 28 forward with the hitch rod 3 extended, the hitch rod 3 is moved between the contact ring 3a of the hitch rod 3 and the cylinder 10 on the trailer body side, and the hitch rod 3 is retracted. Is regulated.

An L-shaped member 28d, which is engaged with a torsion coil spring (spring) 44 described later, is fixed to the long side 28e of the locking lever 28 so as to protrude leftward in plan view, and a guide 34 described later. The pin 28f to be engaged with the projection is fixed to protrude rightward in plan view. A wire 56 is connected to the vicinity of the tip of the long side 28e of the locking lever 28 to operate the locking lever 28 from the towing vehicle side. 28e is pulled up.

A pipe 27 a for surrounding the outer periphery of the bolt 29 is integrally inserted into and fixed to the support piece 27.
A torsion coil spring 44 is wound around the pipe 27a, and the locking lever 28 is rotated in a direction in which the stopper member 31 is pulled upward. The torsion coil spring 44 has one end in contact with the upper surface of the front end of the traction frame 2 and the other end in contact with the protruding portion of the L-shaped member 28d.

A guide body (click mechanism) for holding the rotation position of the engagement and disengagement of the stopper member 31 is provided on the locking lever 28.
34 are provided.

The guide body 34 is formed in a substantially U-shaped cross section in which both ends of the plate material are bent downward.
The eight pins 28f are alternately locked at two different positions to hold the turning position of the locking lever 28 at either the engaged or disengaged position.

More specifically, the guide 34 is provided with the locking lever 2.
One end is rotatably supported via a bolt 35 and a nut 35a on a support member 33 that is fixed to the rear of a support piece 27 that supports the torsion coil 27. A torsion coil spring wound around the bolt 35 is provided. The tip is elastically urged to rotate the front end in the traveling direction by 38.

Further, the guide body 34 is arranged so that the left side surface 34f on the left side in plan view rubs against the right side surface of the locking lever 28, and the pin 2 of the locking lever 28 is provided on the left side surface 34f.
A locking step 53 for locking the 8f at two positions is formed. The locking step 53 is formed by forming a first notch 42 and a second notch 43 on the left side surface 34f.

The first notch 42 is a substantially V-shaped notch formed at a substantially middle position in the longitudinal direction of the guide body 34 and extending downward. A pin 28f is placed on the lower edge of the first notch 42. A first step portion 54 for locking is formed, and the pin 28f is moved upward at the upper edge of the first notch 42 to rotate the guide body backward, thereby allowing the pin 28f to move upward. An inclined surface 34d is formed.

The second notch 43 is formed of a substantially U-shaped notch formed adjacent to the tip end of the first notch 42, and the lower edge of the second notch 43 is used to mount the pin 28f and lock it. Second
A step 55 is formed, and the upper edge of the second notch 43 is provided with a pin 28.
A pin contact surface 34h for restricting the upward movement of f is formed.

The inclined surface 34 d of the first notch 42 and the second notch 4
3 is smoothly connected by an arc-shaped surface 34e, and the height from the back of the second notch 43 to the arc-shaped surface 34e is about half the length of the pin contact surface 34h. It is formed at the height of.

The guide body 34 has a guide elastic plate 36 for guiding the pin 28f locked to the second step 55 to guide it to the first step 54.

The guide elastic plate 36 is made of a plate having elasticity, is spaced from the arc-shaped surface 34e, and has its tip extended to the vicinity of the pin contact surface 34h. Near the middle of the guide elastic plate 36, that is, the first step portion 54
In the vicinity of the position where it intersects, the distal end is bent at an obtuse angle so as to gradually approach the pin sliding surface 34g formed in the inner part of the second notch 43. The moved pin 28f is guided to a guide surface 36a formed below the guide elastic plate 36.

In the vicinity of the bent portion of the guide surface 36a, a notch 3 having a size such that the pin 28f of the locking lever 28 can easily pass therethrough.
6c is formed, and the guide body 3 is guided along the guide surface 36a.
The pin 28f moved to the root side of the fourth member 4 is returned to the first step portion 54.

Next, the operation will be described.

When the trailer T is connected to the towing vehicle and the vehicle is towed, the switching device 9 is not operated, that is, the stopper member 31 is detached from between the sliding cylinder 13 and the cylindrical body 10.

When the towing vehicle is braked during towing, the trailer T approaches the towing vehicle due to the inertia of the trailer T. At this time, the hitch rod 3 slides rearward in the tubular body 10 while pressing and contracting the gas spring 14, and pushes the upper end of the rotating member 16 rearward. The rotating member rotates around the bolt 45 and pulls the first connecting member 17 forward. As a result, the second connecting member 18 is also pulled forward, and the third connecting member 20 and the fourth connecting member 21 are also drawn from the first center side projecting piece 20b and the second center side projecting piece 21b.

Third connecting member 20 and fourth connecting member 21
Rotates about the pipes 22 and 23, respectively,
The connecting member 24 and the sixth connecting member 25 are pulled forward. Then, the operating levers 5b, 5b of the brake devices 5a, 5a mounted on the left and right inner running wheels 5, 5 are simultaneously pulled, respectively, and the brake devices 5a, 5a are operated.

At this time, the workability of the brake is not necessarily the same for the left and right, but since the second connecting member 18 can rotate in the horizontal direction, the operating levers 5b of the left and right brake devices 5a are moved in the front-rear direction. Left or right brake device 5a
Even if the amount of rotation of the operation lever 5b until the same braking force is generated is different, the second connecting member 18 rotates around the pin 19, and the fifth and fourth connecting members 20 and the fourth connecting member 21 It is possible to apply substantially the same tensile force to the sixth connecting members 24 and 25 and to apply substantially the same braking force to the left and right inner running wheels 5 and 5.

Next, an operation of switching the switching device 9 to an operating state, that is, a state in which the stopper member 31 is positioned between the sliding cylinder 13 and the cylindrical body 10 to restrict the contraction of the hitch rod 3 will be described.

When the switching device 9 is not operated, the pin 28f of the locking lever 28 is connected to the first step 54 of the first notch 42.
It is located in. When the long side 28e of the locking lever 28 is pulled in the traveling direction from the towing vehicle via the wire 56, the pin 28f slides on the inclined surface 34d of the first notch 42 and climbs over the arc-shaped surface 34e. As shown in FIG.
The notch 43 moves to the second step 55 and is locked.

At this time, the locking lever 28 is
, And the stopper member 31 is pressed against the hitch rod 3 exposed from between the sliding cylinder 13 and the cylindrical body 10. Since the stopper member 31 is urged by the spring 32 so as to be retractable, the stopper member 31 is pressed against the outer peripheral surface of the hitch rod 3 and pressed.

The urging force of the torsion coil spring 44 for urging the locking lever 28 is larger than the urging force of the torsion coil spring 38 for urging the guide 34, so that the locking lever 28 The pin 28f locked to the second step 55 is firmly held at a predetermined position.

Therefore, even when the towing vehicle is moved backward, the hitch rod 3 is prevented from moving backward by the stopper member 31 located between the sliding cylinder 13 and the cylindrical body 10, and the inner traveling wheels 5, 5 are moved.
The brake devices 5a, 5a provided in the vehicle are not operated.

When returning the switching device 9 to the non-operating state, the long side 28e of the locking lever 28 is again pulled in the traveling direction from the towing vehicle side.

The pin 28f moves upward with the rotation of the locking lever 28. The tip of the guide elastic plate 36 and the guide body 3
4 is formed between the pin sliding surface 34g and the pin sliding surface 34g.
The pin 28f is formed to be narrower than the radius of 8f.
The distal end of the guide elastic plate 36 is displaced toward the distal end of the guide body 34 while being pushed away, and comes into contact with the pin contact surface 34h of the guide body 34 as shown in FIG.

In this state, when the user stops pulling the locking lever 28 and releases the pulling force in the traveling direction, the locking lever 2
8 rotates in the direction of lowering the long side 28e by the urging force of the torsion coil spring 44.

Since the gap between the pin sliding surface 34g of the guide body 34 and the tip of the guide elastic plate 36 is formed smaller than the radius of the pin 28f, the pin 28f is distributed to the lower side of the guide elastic plate 36, It moves to the base side of the guide body 34 while sliding on 36a.

Then, the stopper member 31 is moved in a direction in which the stopper member 31 is separated from the space between the sliding cylinder 13 and the cylindrical body 10 with the rotation of the locking lever 28.

When the pin 28f reaches the notch 36c formed near the bent portion of the guide elastic plate 36, the guide body 34 is rotated forward through the pin 28f through the notch 36c by the action of the torsion coil spring 38. . Pin 2 that has passed through notch 36c
8f is locked to the first step portion 54, and the switching device 9 returns to the inoperative state.

As described above, the switching device 9 can be reliably switched between the state in which the hitch rod 3 is allowed to slide and the state in which the sliding of the hitch rod 3 is prevented.
a can be prevented from being operated, and erroneous braking on the trailer can be prevented.

Further, by simply pulling the locking lever 28, the position of the stopper member 31 is shifted from the position where the hitch rod 3 is allowed to slide to the position where the slide of the hitch rod 3 is stopped, or from the position where the slide of the hitch rod 3 is stopped. The brake device 51 can be alternately moved to the position where the brake device 51 is operated, and the operation and non-operation of the braking device 51 can be switched by a simple operation.

The means for pulling the locking lever 28 from the towing vehicle side is not limited to the wire 56, and may be a chain, a rope having sufficient strength for operation, or a rod-shaped one. Good.

[0070]

In summary, according to the present invention, the following excellent effects can be obtained.

(1) It is possible to prevent the operation and non-operation of the braking device from being switched even if the vehicle travels in the reverse direction, and to prevent the operation of the braking device during the reverse driving.

(2) The operation and non-operation of the braking device can be switched by a simple operation.

[Brief description of the drawings]

FIG. 1 is a plan view of a trailer showing a preferred embodiment of the present invention.

FIG. 2 is a partially enlarged view of FIG.

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

FIG. 4 is a sectional view taken along line IV-IV of FIG.

FIG. 5 is a bottom view of a traveling wheel portion of the trailer.

FIG. 6 is a side view of the switching device when the braking device is in a non-operation state.

FIG. 7 is a side view of the switching device in the process of switching the braking device from the non-operation state to the operation state.

FIG. 8 is an enlarged view of a main part showing a conventional trailer braking device.

[Explanation of symbols]

 Reference Signs List 3 hitch rod 3a contact ring (projection) 5a brake device (brake) 9 switching device (switching means) 28 locking lever (lever member) 31 stopper member 34 guide body (click mechanism) 44 torsion coil spring (spring) 50 trailer Body 51 Braking device 56 Wire

Claims (3)

[Claims] 1. A trailer which is provided on a trailer body with a hitch rod connected to a tow vehicle so as to be extendable and retractable, and which operates the brake by the retracting movement of the hitch rod with respect to the trailer body when the tow vehicle stops. In the braking device,
The trailer body is provided with switching means for movably supporting a stopper member which is engaged at the extended position of the hitch rod to restrict the contraction of the hitch rod, and which is operated from the towing vehicle side by a wire or the like. A trailer braking device, characterized in that: 2. A hitch rod having a projection at a tip end thereof, a stopper member interposed between the projection and the trailer body to engage and restrict the contraction of the hitch rod, and the switching means comprises the stopper member. 2. The trailer braking device according to claim 1, further comprising a lever member that pivots to move between the engagement position and the disengagement position, and the lever member is operated by a wire or the like from the towing vehicle side. 3. The lever member is biased by a spring so as to rotate in one direction, and the lever member is provided with a click mechanism for holding a rotation position of engagement and disengagement. 3. The method according to claim 2, wherein the detaching position is alternately repeated.
The trailer braking device according to claim 1.