KR950000314Y1 - Vehicle for pulling a carriage - Google Patents

Abstract

No content.

Description

Tow truck

1 is a plan view showing the main part of the towing trolley.

2 is a longitudinal sectional view of the central portion of FIG.

3 is an enlarged cross-sectional view of the arrow 3-3 of FIG.

4 is a plan view showing a partially omitted another embodiment of the braking device.

5 is a side view of the braking system of FIG.

6 is an enlarged cross-sectional view of the braking operation mechanism.

7 is a right side view of FIG.

8 is a plan view showing a part of another embodiment of the braking device omitted.

9 is a front view showing the braking operation mechanism of FIG.

10 is a cross-sectional view showing another embodiment of the position change detector sphere.

* Explanation of symbols for the main parts of the drawings

4: front wheel 5: rear wheel

6: retractor 7a: small groove

7: connecting frame 8a: hemisphere

8b: taper portion 8: braking rod

9,25: braking operation member 9a: inclined surface

10b: head 10: braking

10a: foundation end 11: the vehicle itself

11a: Frame 12: guide groove

12a: horizontal part 13,21,27,36: axis

14, 28, 32: coil spring 15: connector

16: bearing bearing 17: water pressure plate

18c: sloped material 18a: horizontal material

18: framework 18: framework

18b, 18d: joint 19: corro

20: rotating arm 22, 26: cable end

23: cable with sheath 23a: sheath

24: bearing 25: braking operation member

27; Pin 30,31: hydraulic cylinder

33,34: Piston 32a, 34a: Piston Rod

40: L type bracket 41: Double nut

42: bracket 42a: top plate

43: spring plate 44: nut

45,45 ': Hydraulic hose A: Position change detector

B: Braking Manipulator

The present invention relates to a towing trolley which is connected to a driving car or connected to a trolley to tow driving, and more particularly, to a towing trolley having an operating device that is reliably and automatically operated at a stop while driving.

2. Description of the Related Art Conventionally, a brake device for a trolley cart is disclosed in Japanese Unexamined Patent Application Publication Nos. 1-36685 and 38-1823, and is operated by a manual operation lever.

However, the traction trolley provided with a braking apparatus is not put to practical use and is not known.

Conventional towing trolleys do not include a braking device that operates when the vehicle is stopped while driving, and attempts to brake all of them by the braking force of the driving car. However, when the heavy loads are being loaded, the inertia force during driving is so large that it exceeds the braking force of the driving bogie, and even if the braking device of the driving car that operates at the stop during driving is driven by electric power, it is pushed out by the towing trolley which is overtaken from behind. There was a high risk that the drive would overrun ahead of the scheduled stops and cause an accident. In addition, if one or several vehicles are connected even in the empty towing truck, when the braking force of the driving vehicle is stopped during driving, the following towing truck gradually collides with the truck forward to generate a loud metallic shock sound and make a loud noise around. In addition, the trolley of the forces are swung to the left and right in a twisted form, and there is a risk of contact with people or objects around. In addition, there is also a problem that the connector portion is particularly easy to break due to the repetition of the above-described impact action, which has emerged as a problem.

As a means for solving the above-mentioned problems of the prior art, the towing trolley according to the present invention includes a front wheel 4, which is a free wheel, and a rear wheel 5, which is a fixed wheel, under the vehicle body 11, and is approximately the center of the front of the vehicle body. And a retractor 6 connected to the front vehicle, and a coupler 15 for connecting the retractor of the following bogie to a substantially central portion of the rear portion of the vehicle body, characterized by the following constitution.

(A) The base end of the retractor 6 is connected to the front of the vehicle body 11 so that forward and backward movement is possible with a constant stroke before and after the traveling direction.

(B) In the front part of the vehicle body 11, the braking rod 8 is arranged substantially parallel to the forward and backward movement direction of the retractor 6, and at least the same amount as the movement stroke of the retractor 6 in the axial direction. It is installed to be movable.

(C) The braking rod 8 always receives an acting force in a direction for releasing a braking action of the braking piece described later with the spring 14 or the like, and the braking rod 8 is connected to the retractor 6 to provide the acting force. Thus, the base end of the retractor 6 is always pressed to the position of the forward limit.

(D) The braking piece 10 for braking the rear wheels 5 is freely provided to fall or contact the rear wheels 5.

(E) A braking operation member 9 which presses the braking piece 10 against the rear wheel 5 to be contacted is provided at the rear of the vehicle body 11, and the braking operation member 9 and the braking rod 8 ) Is connected in a series of actions (see FIGS. 1 to 3).

In the above-mentioned towing trolley, two rear wheels 5 are arranged under the vehicle body 11 in a symmetrical state, and the rear wheels (the braking pieces 10 for braking the rear wheels 5 and the respective braking pieces are rear wheels ( 5) The braking operation members 9 which are pressed against and contact with each other are provided in two sets, one pair on one rear wheel, and the two braking operation members 9 and 9 and the braking rod 8 of the front part of the vehicle body. In addition, it is also characterized by the point that the plane shape is connected in series operation by the framework 18 of the substantially isosceles triangle which makes the position of a braking rod a vertex (refer FIG. 1).

The towing trolley according to the second invention also includes a front wheel 4, which is a free wheel, and a rear wheel 5, which is a fixed wheel, under the vehicle body 11, and a retractor connected to the front vehicle at the center of the front of the vehicle body ( 6), and a connector 15 for connecting a retractor of a subsequent bogie to an approximately center portion of the rear portion of the vehicle body, characterized by the following configuration.

(A) The base end of the retractor 6 is connected to the front of the vehicle body 11 so that forward and backward movement is possible with a constant stroke before and after the traveling direction.

(B) In the front part of the vehicle body 11, the braking rod 8 is arranged substantially parallel to the forward and backward movement direction of the retractor 6, and at least the same amount as the movement stroke of the retractor 6 in the axial direction. It is installed to be movable.

(C) The braking rod 8 always receives an acting force in a direction for releasing a braking action of the braking piece described later with the spring 14 or the like, and the braking rod 8 is connected to the retractor 6 to provide the acting force. Thus, the base end of the retractor 6 is always pressed to the position of the forward limit.

(D) The braking piece 10 for braking the rear wheels 5 is freely provided to fall or contact the rear wheels 5.

(E) A position change detector mechanism A for detecting a position change in the retraction direction of the braking piece 10 or the retractor 6 is provided.

(F) A braking operation mechanism B is provided for pressing the braking piece 10 against the rear wheel 5 to contact the braking operation mechanism B. The braking operation mechanism B is connected to the position change detector opening A. , The braking operation mechanism B is driven in accordance with the position change detected by the position change detector tool A, and the braking piece 10 is pressed against the rear wheel 5 to be brought into contact with each other (see FIGS. 4 to 10). .

In the above-mentioned towing trolley | bogie, the position change detector tool A and the braking operation mechanism B are connected by the cable 23 with a sheath in the relationship which transmits a mechanical displacement and a force (FIG. 4, FIG. 5) and the position change detector mechanism A are configured to detect the position change of the brake rod 8 as a hydraulic pressure or an electric quantity, and the braking operation mechanism B operates based on the hydraulic pressure or the electrical quantity. It is also characterized by the fact that it is constituted as a mechanism having a hydraulic or electric drive.

The braking rod 8 is always pressed in the direction (running direction forward) of releasing the braking action of the braking piece 10 by the action force of the spring 14. Therefore, the braking operation member 9 connected in series with the braking rod 8 is also avoided in the direction of releasing the braking action.

Therefore, the rear wheel 5 rotates freely without being subjected to braking by the braking piece 10 and, for example, runs freely following the driving vehicle connected to the retractor 6. By the way, when the driving vehicle stops by operating the braking device and the inertia kinetic force of the traction trolley 1 behind it exceeds the force of the spring 14 acting on the brake rod 8, the traction trolley 1 The vehicle body 11 advances forward by the amount of stroke permitted at the base end of the retractor 6 to approach the driving vehicle.

As a result, the relative movement of the stroke occurs between the base end of the retractor 6 and the vehicle body 11, and the braking rod 8 associated with the retractor 6 is applied to the brake rod 8 by the relative movement. Move back.

The retraction movement of the braking rod 8 is transmitted as an operation of the braking operation member 9 in a relation of directly operating in series, and the braking operation member 9 causes the braking piece 10 to have a large braking force on the rear wheel 5. Generates. Therefore, the rotational force of the rear wheel 5 is stopped and the towing trolley 1 is stopped.

In the case of the configuration of the position change detector mechanism A and the braking operation mechanism B (FIGS. 4 to 10), the operation principle of braking and stopping the traction cart 1 is the same. As long as the stop positions of the drive car, the towing cart 1, and the front and rear tow carts do not change, the vehicle is held in the braking state of the rear wheel 5 as it is.

Subsequently, when the stopped driving car starts to run, first, the retractor 6 moves forward together with the driving car, so that the vehicle body 11 of the towing vehicle 1 is tensioned in a step in which the base end thereof is advanced with a constant stroke. Towing.

At this time, as the basic end of the retractor 6 moves forward, the braking rod 8 also gradually moves forward by the action of the spring 14, and the braking operation member 9 or 25 before the towing cart 1 travels. ) Separates the braking piece 10 from the rear wheel 5 to release the braking action. Therefore, there is no problem at the start of driving of the towing trolley 1.

EXAMPLE

Next, the illustrated embodiment of the present invention will be described.

The tow trolley 1 shown in FIGS. 1 to 4 has two front wheels 4 (4), which are free wheels (free casters), and a fixed wheel behind the rectangular body body 11, in the plane. (5) (5), having a retractor (6) to be connected to the front vehicle (drive car or tow truck) at approximately the center of the front of the vehicle body, and the retractor (6) of the subsequent bogie to the approximately central portion of the rear of the vehicle body. The connector 15 for connecting is provided.

The rear wheel 5 is not limited to a fixed vehicle, and may be, for example, a wheel provided with a switching device between a free state and a fixed state as disclosed in Japanese Unexamined Patent Application Publication No. 63-38133.

As shown in FIG. 2 and FIG. 3, the U-shaped connecting frame 7 is installed in the approximately center position of the front part of the vehicle body from the front, and on both side surfaces of the connecting frame 7 as shown in FIG. As a result, the L-shaped guide groove 12 is formed in a left-right symmetrical shape. The base end portion of the retractor 6 is provided to move forward and backward with a predetermined stroke before and after the traveling direction of the towing cart 1 by the shaft 13 freely sliding along the guide groove 12.

The length of the horizontal portion 12a of the L-shaped guide groove 12 corresponds to the forward and backward movement stroke of the basic end of the retractor 6. The vertical part 12b is used when the retractor 6 when not in use is stored vertically as shown by the dashed-dotted line in FIG. The base end of the vertical retractor 6 enters the small groove 7a provided in the bottom face of the connecting frame 7.

The braking rod 8 supported by the sliding bearing 16 at the position just below the connecting frame 7 as the lower surface portion of the front part of the vehicle body 11 is disposed substantially parallel to the moving direction of the retractor 6. It is provided so as to be movable in at least the same amount as the moving stroke of the retractor 6 in the axial direction. The braking rod 8 releases the braking action of the braking piece described later between the hemisphere portion 8a, which is formed at a slightly larger diameter at the front end of the braking rod 8 as a portion ahead of the sliding bearing 16. The coil spring 14 of the compression type which always operates an action force to a direction is wound up. The two are connected by contacting the pressure receiving plate 17 provided in the vertical direction on the lower surface of the retractor 6 in contact with the hemisphere 8a at the front end of the braking rod 8. By the operation of the coil spring 14, the shaft 13 of the base end is always pressed to the position of the forward downward path of the guide groove 12 (right end of the horizontal portion 12a in the third diagram). The means for associating the retractor 6 with the brake rod 8 is not limited to the method by the hydraulic plate 17 as long as the above function is achieved, and may be performed by other methods.

At the position just above the rear wheel 5, the braking piece 10 made of a spring-like flat material excellent in elasticity (flexibility) is freely attached or detached from the outer circumferential surface of the rear wheel 5. . As for the braking piece 10, the base end part 10a is being fixed to the vehicle body 11 side, and the head part 10b is formed in the flat ring shape which is easy to press.

The braking piece 10 is normally separated from the rear wheel 5 by its spring property, but is pressed against the outer circumferential surface of the rear wheel 5 by pressing down on the head 10b to generate a braking force.

The braking operation member 9 which pushes down the head portion 10b of the braking piece 10 and is pressed against the rear wheel 5 to be in contact with the rear end portion has a slanted surface 9a having a slender end that is lowered toward the rear end. It is formed as a shape member, and the sliding motion in an axial direction is supported freely by the sliding bearing 16 provided in the lower surface of a vehicle body rear part.

As shown in FIG. 1, a braking piece 10 and a braking operation member 9 for braking each rear wheel with respect to two rear wheels 5 and 5 provided in a symmetrical arrangement below the vehicle body in a plan view. Is installed once on one rear wheel (5), the two left and right braking operation members (9) and the front part of the vehicle body and the braking rod (8), the planar shape of the braking rod (8) by the copper tube and joint The high rigidity frame 18 assembled into a substantially isosceles triangle with its position as a vertex is connected in a series of motions (moves).

Both ends of the horizontal member 18a corresponding to the bottom of the triangle are connected at right angles to the two left and right braking operation members 9 and 9 and the joint 18b. The heads of the two horizontal members 18c corresponding to the inclined sides are connected to the ends of the braking rods 8 by joints 18d.

When the tow truck 1 is towed and driven by connecting the retractor 6 to the drive car, the shaft 13 of the basic end of the retractor 6 contacts the front end of the guide groove 12 so that the traction force is transmitted. At this time, the brake rod 8 is also pressed by the coil spring 14 along the hydraulic plate 17 moved forward with the retractor 6 to move forward.

Accordingly, the braking manipulation member 9 associated with the braking rod 8 also moves forward through the frame 18, and the inclined surface 9a of the braking manipulation member 9 is the head of the braking piece 10. The light contact with 10b or a slightly separated relationship occurs. Therefore, the braking piece 10 is in a non-braking state in which it rotates freely.

When the driving vehicle stops by operating the braking device, the traction trolley 1 further advances in accordance with the motion inertia while the retractor 6 and the shaft 13 of the base end thereof also stop together with the driving vehicle. At this time, the tow trolley 1 and the forward are hung until the shaft 13 is in contact with the rear end of the horizontal portion 12a of the guide groove 12.

Thus, the relative movement of the stroke defined as the length of the horizontal portion 12a of the guide groove 12 occurs between the retractor 6 and the vehicle body 11. The hydraulic plate 17 of the retractor 6 moves the brake rod 8 backward by the relative movement shown by the dashed-dotted line in FIG. Since the braking operation member 9 is moved together backward through the frame 18 by the movement of the braking rod 8 backward, the inclined surface 9a pushes down the braking piece 10 and the rear wheel 5 The traction trolley 1 is stopped because the outer circumferential surface of the wheel is pressed to make contact with each other and a large braking force is generated to stop the improvement of the rear wheel 5.

The braking and stopping of the towing trolley 1 is at a position halfway between the shaft 13 of the basic end of the retractor 6 moving from the front end to the rear end of the horizontal portion 12a of the guide groove 12, at least. Carefully design and manufacture the shaft 13 abuts on the rear end of the horizontal portion 12a so that the so-called collision force (impact force) is achieved at a position where it is not transmitted to the driving vehicle side.

The traction trolley 1 once stopped as described above is designed to make the actuation force of the coil spring 14 smaller than the stationary inertia force or the rotational resistance of the wheels 4 and 5, thereby self-holding the state of the stop due to braking. . Of course, when the towing by the driving car is started, as described above, the towing cart 1 directly restores to the brake release state and runs without a problem.

In addition, when the front wheel 4 is a wheel with a conventionally known brake device, it is applied to the case where the tow truck 1 is used for truck transportation and the like, and inadvertent movement is transported in a stable state without fear of damage. You can do it.

Second Embodiment

The tow trolley 1 shown in FIGS. 4 to 7 is also applied to the tow trolley 1 shown in the first embodiment, and in front of the vehicle body 11 in the retraction direction of the braking rod 8. The position change detector mechanism A for detecting the movement of the position as the position change is provided.

In addition, at the position near each rear wheel 5 in the rear of the vehicle body, the position change detector sphere A is driven based on the position change of the braking rod 8 detected, and the braking piece 10 is driven on the rear wheel 5. Is provided with a braking operation mechanism (B) which is pressed against and in contact with each other, and the position change detector (A) and the braking operation mechanism (B) are brought into contact with a sheathed cable 23 that transmits mechanical displacement and force. have.

As shown in Fig. 5, the position change detector sphere A is rotated by the shaft 21 at one end of the L-shaped bracket 40 fixed to the frame 11a. A tapered portion 8b having a substantially intermediate portion of the arm 20 rotatably supported and a corro 19 provided at one end of the rotating arm 20 in a slender shape at the rear end of the braking rod 8. Abuts on

The cable end 22 of the cable 23 with a sheath is connected to the other end part of the said rotating arm 20 in the tangential direction with respect to the rotating arm 20. As shown in FIG.

The end of the sheath 23a is fixed to the other end of the L-shaped bracket 40 by a double nut 41. Accordingly, when the braking rod 8 moves backward, the rotary arm 20 is rotated about the shaft 21 as shown by the two-dot chain line in accordance with the change of the position of the tapered portion 8b at the rear end thereof. The sheathed cable 23 is tensioned and moved by the length of.

As shown in FIGS. 5 and 6, the braking operation mechanism B bears the bearing 24 on the upper plate 42a of the bracket 42 of the rear wheel 5 fixed to the rear lower surface of the vehicle body 11. ) Is fixedly attached downwards. The braking operation member 25 is provided in a relatively downward position of the bearing 24 so as to rotate freely about the 27 and one end of the braking operation member 25 rotates in the clockwise direction in the drawing. The head 10b of 10 is pressed against and pushed down.

The other end of the braking operation member 25 is connected with a cable end 26 of a cable with sheath 23. As shown in FIG. 5, the edge part of the sheath 23a is being fixed to the one surface of the spring receiving plate 43 fixed to the frame 11b of the vehicle body 11 with the nut 44. As shown in FIG. On the outer periphery of the cable between the spring receiving plate 43 and the cable end 26, a compression-type coil spring 28 which always pushes the brake operating member 25 back to the non-braking position shown in FIG. It is wound.

Accordingly, when the cable 23 is tensioned and moved in accordance with the rotation of the rotary arm 20 of the position change detector sphere A for detecting the retraction of the brake rod 8, the braking operation of the braking operation mechanism B is performed. The member 25 is rotated about the shaft 27 while pressing and compressing the coil spring 28, the free end of the copper braking operation member 25 abuts the head 10b of the braking piece 10 This pushes it down and pushes against the outer peripheral surface of the rear wheel 5 to generate a large braking force.

However, when the braking rod 8 is moved forward by the coil spring 14, and the force for tensioning the cable 23 is released, this time the coil spring 28 of the braking operation mechanism (B) is the cable end 26 Press to return, and the brake operating member 25 is rotated back to restore the brake release position. Inevitably, since the cable 23 is tensioned, the rotary arm 20 of the position change detector sphere A is restored to the neutral position shown by the solid line in FIG.

Third Embodiment

The braking device shown in FIGS. 8 to 10 is also applied to the traction trolley 1 shown in the first embodiment, and is the same as the second embodiment, with the retraction of the braking rod 8 at the front of the vehicle body. The position change detector mechanism A which detects the movement in a direction as a displacement is provided. In addition, at the position near each rear wheel 5 in the rear of the vehicle body, it is driven based on the position change of the braking rod 8 detected by the position change detector sphere A, and the braking piece 10 is driven on the rear wheel 5. Is provided with a braking operation mechanism (B) for pressing and contacting the. The illustrated embodiment is a hydraulic mechanism together with the position change detector mechanism A and the braking operation mechanism B, and the position change detector mechanism A and the braking operation mechanism B are two hydraulic hoses 45 and 45. ') Is connected.

In the position change detector mechanism A, the vehicle body 11 is arranged such that the rod 33a of the piston 33 in which the fixed hydraulic cylinder 30 is built is substantially perpendicular to the axis of the braking rod 8, The taper portion 8b formed at the rear end of the braking rod 8 is in contact with the corro 19 attached to the tip of the piston rod 33a. Behind the piston 33, a compression type coil spring 32 of restoring action is provided. Therefore, when the braking rod 8 moves backward, the piston rod 33a proportionally moves backward in response to the positional change and gradient of the tapered portion 8b. The hydraulic oil and the hydraulic fluid of the flow rate flow out from the piston front chamber to the hydraulic hose 45 'of the road. On the contrary, the same amount of hydraulic oil flows into the piston rear chamber in the cylinder 30 from the hydraulic hose 45 of the return path. Of course, when the braking operation member 9 is even forward, the piston 33 and the piston rod 33a are moved by the coil spring 32 in accordance with the taper 8b positional change and gradient.

As the piston 33 moves, a considerable amount of hydraulic oil flows from the one hydraulic hose 45 'to the piston front chamber and, on the contrary, hydraulic oil flows from the rear chamber of the piston to the other hydraulic hose 45.

The braking operation mechanism B is configured as a hydraulic cylinder 31 having substantially the same specifications as the hydraulic cylinder 30 of the position change detector mechanism A. As shown in FIG. As shown in FIG. 9, the distal end portion of the rod 34a of the piston 34 has an axle in the middle portion of the braking operation member 25 in which the upper end portion is freely rotatably attached to the bearing 24 by a pin 27. 36).

In the piston rod 34a, a compression coil spring 32 having a restoring action is wound around a portion between the piston 34 and the cylinder bracket.

Therefore, in the hydraulic cylinder 30 of the position change detector mechanism A, the hydraulic pressure is applied to the hydraulic hose 45 'while the piston 33 presses and compresses the coil spring 32 in accordance with the retraction movement of the braking rod 8. When is extruded, the piston 34 of the hydraulic cylinder 31 of the brake operating mechanism B is pressed in proportion to the flow rate and the hydraulic pressure, and moves forward while pressing the coil spring 32 to compress it.

As the piston rod 34a moves forward, the braking operation member 25 is rotated about the shaft 27, and its free end abuts against the head 10b of the braking piece 10, which is pushed down to the rear. Pressing on the wheels 5 compresses them to generate a large braking force.

The hydraulic oil which flowed out from the piston rear chamber of the hydraulic cylinder 31 flows into the piston rear chamber of the hydraulic cylinder 30 of the position change detector opening A via the hydraulic hose 45. On the contrary, when the braking rod 8 is moved forward by the coil spring 14 and the force for pressing the piston rod 33a of the hydraulic cylinder 3 of the position change detector port A is reduced or released, it is sensitive to this. In response, it is directly pressed by the coil spring 32 of the piston 33 and returned. When the hydraulic pressure of the piston front chamber decreases due to the retraction operation of the piston 33, and the hydraulic oil is absorbed from the hydraulic hose 45 ', the hydraulic pressure of the hydraulic cylinder 31 of the brake operating mechanism B decreases and the hydraulic oil As it flows out, in response to this, the piston 34 is directly pushed back by the coil spring 32. By the retraction operation of the piston rod 34a, the braking operation member 25 rotates in the direction of releasing the braking force, the braking piece 10 is separated from the rear wheel 5, and the rear wheel 5 rotates freely. The braking state is restored.

[Other Embodiments]

(1) In FIG. 10, the position change detector mechanism (A) excludes the piston rod (33a) of the hydraulic cylinder (30) parallel to the center line of the brake rod (8), and directly moves the movement of the brake rod (8). An embodiment of the detection and configuration is shown.

(2) The position change detector tool A (including the embodiment of FIG. 4) can also be implemented in a configuration in which the fine motion of the retractor 6 is directly detected.

(3) The position change detector mechanism (A) controls displacement of the piston rod 33a in FIG. 8 or 10, rotation of the rotary arm 20 in FIG. 4, or movement of the brake rod 8 or retractor. It can also be configured as an electrical sensor that converts directly to an electric quantity and detects it, and controls the hydraulic circuit by the electric signal and drives the hydraulic cylinder 31 of the braking operation mechanism B to be drive controlled.

(4) The drive unit of the braking operation mechanism B may be implemented in such a manner that the mechanical output of an electric motor, for example, an electric motor and an solenoid, may be used instead of the hydraulic cylinder 31.

The present invention by the above configuration has the following effects.

In the towing trolley according to the present invention, when the driving vehicle stops during the towing driving, the braking force is automatically applied to the rear wheel 5 of the towing trolley 1, and the vehicle responsively reacts to the stopping of the driving vehicle and stops, It is deviated from side to side by the extraction force on the tow truck) or the momentum to prevent the zigzag scattering.

During the stop, the braking state is self-maintained and there is no fear of moving around due to carelessness. Of course, no loud metallic impact sounds occur during braking stops, and there is no fear of breakage of the connector portion due to repeated collisions.

Claims (5)

Under the car body 11 is provided a front wheel 4, which is a free wheel, and a rear wheel 5, which is a fixed wheel, and the car body 11 has a retractor 6 which is connected to the front vehicle in the center of the front part. (11) A trolley having a coupler 15 for connecting a retractor 6 of a subsequent trolley to a substantially central portion of the rear part, wherein the base end of the retractor 6 is in front of the vehicle body 11 in a forward and backward direction of travel. The forward and backward movements are connected by a constant stroke, and the braking rod 8 is arranged in a direction substantially parallel to the forward and backward movement direction of the retractor 6 and at least in the axial direction. The braking rod 8 is provided so as to be movable in the same amount as the moving stroke of (6), and the braking rod 8 always uses the spring 14 or the like for the action force in the direction of releasing the braking action of the braking piece 10 described later. Being received, the braking rod 8 is associated with the retractor 6 and the action force The base end of the furnace retractor 6 is always pressed to the position of the forward limit, and the braking piece 10 for braking the rear wheel 5 is freely attached or detached from the rear wheel 5. In the braking operation mechanism B for pressing and contacting the braking piece 10 against the rear wheel 5, the vehicle body 11 is provided at the rear portion, and the braking operation mechanism B and the braking rod ( A towing trolley, characterized in that each of which is connected in a series with 8). According to claim 1, two rear wheels 5 are installed in the symmetrical arrangement below the vehicle body 11, the braking piece 10 for braking the rear wheel 5 and each of the braking pieces in the rear wheel ( The braking operation members 9 which are pressed against and contact with each other 5) are provided on one rear wheel 5 one by one, and the two braking operation members 9 and 9 and the braking rods in front of the vehicle body 11 8) is a tow trolley, characterized in that the plane shape is connected in a series of operation by the frame 18 of an isosceles triangle with the top of the braking rod 8 as its apex. Under the car body 11 is provided a front wheel 4, which is a free wheel, and a rear wheel 5, which is a fixed wheel, and the car body 11 has a retractor 6 which is connected to the front vehicle in the center of the front part. (11) A trolley having a coupler 15 for connecting a retractor 6 of a subsequent trolley to a substantially central portion of the rear portion, wherein the base end of the retractor 6 is in front of the vehicle body 11 in a forward and backward direction. The forward and backward movements are connected by a constant stroke, and the braking rod 8 is arranged in a direction substantially parallel to the forward and backward movement direction of the retractor 6 and at least in the axial direction. The braking rod 8 is provided so as to be movable in the same amount as the moving stroke of (6), and the braking rod 8 always uses the spring 14 or the like for the action force in the direction of releasing the braking action of the braking piece 10 described later. Being received, the braking rod 8 is associated with the retractor 6 and the action force The base end of the furnace retractor 6 is always pressed to the position of the forward limit, and the braking piece 10 for braking the rear wheel 5 is freely attached or detached from the back wheel 5. And a position change detector mechanism (A) for detecting a position change in the retraction direction of the brake rod (8) or the retractor (6), and a rear wheel (5) of the brake piece (10). A braking operation mechanism B is provided which is pressed against and touched with respect to the braking operation mechanism B. The braking operation mechanism B is in contact with the position change detector sphere A, and braking in accordance with the displacement detected by the position change detector sphere A. The operation mechanism (B) is driven and the braking piece (10) is characterized in that the pull cart, characterized in that by pressing against the rear wheel (5). 4. The traction trolley according to claim 3, wherein the position change detector mechanism (A) and the braking operation mechanism (B) are connected in a relationship of transmitting mechanical displacement and force by a cable with a sheath (23). The position change detector mechanism A is configured to detect the displacement of the brake rod 8 as a hydraulic pressure or an electric quantity, and the braking operation mechanism B operates based on the hydraulic pressure or the electrical quantity. A towing trolley, which is configured as a mechanism having a hydraulic or electric drive unit.