JP7813660B2 - Vehicle transport vehicle - Google Patents

Description

The present invention relates to a vehicle transporter, particularly a vehicle transporter equipped with a tilt frame supported at the rear of the vehicle body so that it can be dumped and moved back and forth; a lift device that forcibly dumps the tilt frame; a body having a vehicle loading section on which another vehicle can be placed and that can slide back and forth on the tilt frame; a chain-driven longitudinal drive device having a chain fixed to the body that forcibly slides the body on the tilt frame; a sensor device that detects the sliding position of the body relative to the tilt frame; a remote control device that can command the execution and temporary suspension of the operating modes of the longitudinal drive device and lift device involved in the loading and unloading processes of other vehicles; and a control device that can control switching between the operations of the longitudinal drive device and lift device based on the output of the remote control device and sensor device.

The above-mentioned vehicle transporter is known in the art, as disclosed in Patent Document 1, for example. In this known vehicle, multiple predetermined slide positions of the body relative to the tilt frame are directly detected using multiple limit switches, each of which has a dog and proximity sensor, and is installed between the body and the tilt frame.

Patent No. 3648075

The vehicle transporter described in Patent Document 1 allows the body to be unloaded and loaded at any time by remote control operation, and if the remote control operation is stopped midway through the body unloading or loading operation, the body operation can be temporarily stopped.

However, if the body were to shift from its paused position for some reason (for example, if a worker touched the operating part of the hydraulic control valve for driving the body without operating the remote control during maintenance) while the body was temporarily stopped, it would be difficult to determine the direction in which the body had shifted because there was no unloading or loading signal from the remote control device, which could reduce the accuracy of control performed after the process was resumed using the remote control. For example, if the body were to temporarily stop during the unloading process before a specific limit switch that determines the start of dump truck lifting was detected, and the body shifted during the pause and exceeded the detection position of the specific limit switch, the situation could not be accurately determined, which could affect subsequent control.

Instead of, or in addition to, the method of directly detecting when the body has reached a predetermined sliding position using the limit switch described above, as in the vehicle transporter of Patent Document 1, an alternative is to use a rotation amount sensor to detect the amount of rotation of the rotating shaft of the front and rear drive unit that rotates in conjunction with the chain, and then detect the sliding position of the body based on that amount of rotation. In this case, a typical rotation amount sensor is known in the art, for example, to have a structure that includes a sensor gear with multiple dog teeth on its outer periphery that rotates in conjunction with the rotating shaft, and a proximity sensor that can detect the dog teeth. However, because the sensor gear of this known rotation amount sensor has multiple dog teeth with the same tooth width arranged at an equal pitch, even if the amount of rotation can be detected, it is difficult to determine the direction of rotation.

Therefore, even with the above alternative, if the remote control operation is stopped midway through a body unloading or loading operation to temporarily halt the body operation, and the body shifts from the paused position for some reason, it is difficult for the rotation amount sensor to easily determine the direction in which the body has shifted. Therefore, when a paused process is resumed via remote control operation, the control device will resume the process from a body position different from the body position it recognized before the pause, which also reduces the accuracy of the control.

The present invention was proposed in light of the above, and aims to provide a vehicle transporter that can solve the problems of conventional structures.

To achieve the above-mentioned objective, the present invention provides a tilt frame supported at the rear of the vehicle body so that it can be dumped and moved back and forth; a lift device that forcibly dumps the tilt frame; a body having a vehicle loading section on which another vehicle can be placed and slidable in the fore-and-aft direction on the tilt frame; a chain-driven front-and-aft drive device having a chain fixed to the body and forcibly sliding the body on the tilt frame; a sensor device that detects the slide position of the body relative to the tilt frame; a remote control device that can command the execution and temporary suspension of the operation modes of the front-and-aft drive device and the lift device involved in the loading and unloading processes of other vehicles; and a device that switches the operation of the front-and-aft drive device and the lift device based on the output of the remote control device and the sensor device. In a vehicle transporter equipped with a control device capable of controlling the chain, the front and rear drive device has a rotating shaft that rotates in conjunction with the chain, and the sensor device includes at least a rotation amount sensor that can detect the amount of rotation of the rotating shaft, the rotation amount sensor having a sensor gear with a plurality of dog teeth arranged at intervals in the circumferential direction on its outer periphery that rotates in conjunction with the rotating shaft, and a proximity sensor that can detect the dog teeth, the plurality of dog teeth are set to have a tooth shape and pitch such that the output pattern of the proximity sensor that detects them is repeated cyclically as the sensor gear rotates and is different between when the sensor gear is rotating forward and when it is rotating reversely, and the control device is capable of calculating the amount of rotation and determining the rotation direction of the rotating shaft based on the output pattern of the proximity sensor.

In addition to the first feature, the present invention has a second feature in that the multiple dog teeth with different tooth widths are arranged on the outer periphery of the sensor gear in different arrangement patterns during forward and reverse rotation of the sensor gear.

In addition to the first or second feature, the present invention has a third feature in that, if the body shifts without operation of the remote control device while the body is temporarily stopped during the loading process or the unloading process, the control device has means for calculating and storing the direction and amount of shift based on the output pattern, and is capable of determining, based on this memory, whether to return the body to the initial position of the temporary stop when the temporary stop is released, and, if it is determined that the body should be returned, is capable of controlling the longitudinal drive device so that the body returns to the initial position.

According to the first feature, the vehicle transporter has a front-rear drive device that forcibly slides the body relative to the tilt frame, which has a rotating shaft for driving a chain, and a sensor device that includes a rotation amount sensor that can detect the amount of rotation of the rotating shaft. The rotation amount sensor includes a sensor gear that has multiple dog teeth on its outer periphery and rotates in conjunction with the rotating shaft, and a proximity sensor that can detect the dog teeth. The multiple dog teeth are set to have a tooth shape and pitch such that the output pattern of the proximity sensor that detects them is repeated periodically as the sensor gear rotates and is different when the sensor gear is rotating forward and reverse. The control device can calculate the amount of rotation of the rotating shaft based on the output pattern of the proximity sensor and can determine the rotation direction of the rotating shaft. As a result, if the body shifts from the pause position for some reason while the body is being temporarily stopped by remote control during unloading or loading, the control device can accurately determine information about the body's deviation from the pause position (i.e., the direction and amount of deviation) based on the characteristic output pattern of the proximity sensor, which is advantageous in improving the accuracy of process control after the pause is released.

Furthermore, according to the second feature, multiple dog teeth with different tooth widths are arranged on the outer periphery of the sensor gear in different arrangement patterns when the sensor gear is rotating in the forward direction and in the reverse direction. Therefore, the control device can grasp the deviation movement information while the body is temporarily stopped by utilizing the fact that the arrangement pattern (i.e., the order) of pulses with different pulse widths output by the proximity sensor in accordance with the differences in the tooth widths of the multiple dog teeth differs between the forward direction and the reverse direction of the sensor gear. Furthermore, the deviation movement information can be accurately grasped with a simple structure that simply differs the tooth widths of the multiple dog teeth and arranges them in a specific pattern, thereby contributing to cost savings.

According to a third feature, if the body shifts during a temporary stop during the loading or unloading process without the operation of the remote control device, the control device has means for calculating and storing the direction and amount of shift based on the output pattern of the proximity sensor. Based on this storage, the control device can determine whether to return the body to its initial position when the temporary stop is released, and if it determines that the body should be returned, it can control the front-rear drive device to return the body to the initial position. This allows the control device to not only grasp information about the body's shift from the temporary stop position based on the characteristic output pattern of the proximity sensor when the body shifts during a temporary stop without the operation of the remote control, but also determine based on this grasped information whether to return the body to its initial position when the temporary stop is released, and, if it determines that the body should be returned, easily and accurately return the body to the position it was in immediately before the shift, thereby improving the control accuracy of the process that resumes after the temporary stop is released.

FIG. 1 is an overall side view of a vehicle transporter according to an embodiment of the present invention; FIG. 1 is a perspective view showing an assembly of a tilt frame and a subframe equipped with a front-rear drive device and a lift device. FIG. 3 is a perspective view of the subframe; FIG. 3 is a perspective view of the tilt frame; FIG. 3 is a plan view of the tilt frame; Enlarged cross-sectional view taken along line 6-6 of FIG. 5. Enlarged cross-sectional view taken along line 7-7 of FIG. 8 is an enlarged plan view of the portion indicated by the arrow 8 in FIG. 9 of FIG. 8 5A is an enlarged cross-sectional view taken along line 10A-10A in FIG. 5, FIG. 5B is an enlarged cross-sectional view taken along line 10B-10B in FIG. 5, and FIG. 5C is an enlarged cross-sectional view taken along line 10C-10C in FIG. 5. 1A and 1B are longitudinal cross-sectional views of a pivotal connection portion of a lift device to a subframe, showing a state where the lift angle is 0 and a state where the lift angle is at a maximum angle, respectively. A cross-sectional view of the main part of the hoist arm (a cross-sectional view taken along line 12-12 in FIG. 11(A)). An explanatory diagram showing the process of unloading a vehicle transporter 13(e) is an enlarged cross-sectional view of the portion indicated by the arrow 14A in FIG. 13(e), and FIG. 13(b) is an enlarged cross-sectional view of the portion indicated by the arrow 14B in FIG. 13(f). Control block diagram of a vehicle loading device mounted on a vehicle transporter Flowchart of vehicle transporter unloading process (first control example) Flowchart of vehicle transporter loading process (first control example) Flowchart of vehicle transporter unloading process (second control example) Flowchart of vehicle transporter loading process (second control example) 1 is a flowchart of an example of control for dealing with body slippage when a loading or unloading process is temporarily stopped. FIG. 1 is a front view showing an example of a sensor gear in a rotation amount sensor; 10A and 10B are timing charts showing examples of output of an ON signal pulse from a proximity sensor, where (a) shows when the rotating shaft (sensor gear) is rotating forward, and (b) shows when the rotating shaft is rotating backward. 10A and 10B are timing charts showing other examples of output of signal pulses from a proximity sensor, in which (a) shows an example of output of an OFF signal pulse, and (b) shows an example of output of a combination of an ON signal pulse and an OFF signal pulse. FIG. 21 is a front view showing a modified example of the sensor gear; FIG. 22(a) is a timing chart showing an example of an output of an ON signal pulse from the proximity sensor when the rotating shaft (sensor gear) of the modified example rotates forward.

Embodiments of the present invention are described in detail below with reference to the accompanying drawings.

First, referring to Figures 1 to 15, an example structure of an embodiment will be described. The vehicle body F of the vehicle transporter V comprises a chassis frame Fm, which forms the skeleton of the vehicle, extends in the fore-and-aft direction, and from which the front and rear wheels are suspended at the front and rear, and a subframe Fs, which is fixed (for example, by welding, bolts, etc.) to the chassis frame Fm and extends in the fore-and-aft direction. The chassis frame Fm and subframe Fs each have a pair of left and right vertical frames extending in the fore-and-aft direction, and a number of horizontal frames connecting the vertical frames at intervals in the fore-and-aft direction, and are formed in a roughly ladder-like shape.

A pair of left and right roller support brackets 11 protrude from the rearmost horizontal frame of the subframe Fs. As can be seen in Figure 7, these roller support brackets 11 rotatably support a pair of left and right rollers 12 that respectively support the undersides of a pair of left and right vertical frames 21 of the tilt frame T (described below) so that they can slide back and forth.

The vehicle body F is equipped with a vehicle loading device A for loading and unloading other vehicles transported by a vehicle transporter V. This vehicle loading device A includes a tilt frame T supported at the rear of the vehicle body F so that it can be dumped and moved back and forth; a lift device L that forcibly dumps the tilt frame T; a body B having a vehicle loading section on which the other vehicle V' can be placed and slid back and forth on the tilt frame T; a chain-driven longitudinal drive device D having a chain 26 fixed to the body B that forcibly slides the body B on the tilt frame T; a sensor device S that detects the sliding position of the body B relative to the tilt frame T; a remote control device R that can command the execution and temporary suspension of the operating modes of the longitudinal drive device D and lift device L involved in the loading and unloading process of the other vehicle V'; and a control device C that can control the longitudinal drive device D and lift device L based on the outputs of the remote control device R and sensor device S.

Next, specific examples of vehicle loading device A will be described in order, primarily with reference to Figures 2 to 14.

First, as can be seen in Figure 4, the tilt frame T is formed in a ladder shape, with a pair of vertical frames 21 spaced apart from one another on the left and right, and multiple horizontal frames 22 connecting the vertical frames 21 at intervals from front to back. Each vertical frame 21 is made of a channel material with a U-shaped cross section with its opening facing outward, and rollers 33 (see Figures 6 and 10), described below, which are used to smoothly slide the front of the body B back and forth on the tilt frame T, are rollably received within the vertical frame 21.

In addition, both ends of the rearmost horizontal frame 22 extend further outward than the vertical frame 21, and a pair of roller support brackets 28 protrude from these extending portions. Guide rollers 29 (see Figures 4 and 7), which will be described later and are used to smoothly slide the body B back and forth on the tilt frame T, are rotatably supported on the roller support brackets 28.

Furthermore, a ground contact bracket 51 protrudes downward from the middle of the rearmost horizontal frame 22, inside the guide roller 29. This ground contact bracket 51 rotatably supports a ground contact roller 52 that allows the lower rear end of the tilt frame T to move smoothly back and forth relative to the ground when the tilt angle of the tilt frame T is at its maximum and the body B is lowered to the ground (see Figures 13 and 14(B)).

A rotary drive shaft 23f for driving the chain 26 of the front-rear drive unit D is rotatably supported at the front end of the tilt frame T, and a hydraulically operated motor M for driving the rotary drive shaft 23f is fixed coaxially with the rotary drive shaft 23f. The rotational speed of the motor M is adjusted by a hydraulic control circuit for motor drive so that it always remains constant in both forward and reverse directions.

The longitudinal drive device D comprises a pair of left and right front sprockets 24 fixed at a distance from each other in the middle of the rotary drive shaft 23f, a pair of left and right rear sprockets 25 rotatably supported on the rear end of the tilt frame T via rotary driven shafts 23r (see Figure 7) corresponding to the left and right front sprockets 24, a chain 26 wound between the front and rear sprockets 24, 25, and a connecting device J that connects the upper side of each chain 26 to the body B.

As a result, when motor M rotates, the body B synchronizes with the movement of the upper side of the chain 26 via the coupling device J, allowing the body B to move forward and backward in accordance with the rotation of motor M. In this case, the amount of rotation (i.e., number of rotations, rotation angle) of the rotary drive shaft 23f is proportional to the amount of forward and backward sliding of body B relative to the tilt frame T. Therefore, by detecting the amount of rotation of rotary drive shaft 23f as a rotary shaft using the rotation amount sensor RS (described below), it is possible to detect the sliding distance of body B from the forward limit relative to the tilt frame T.

The rotary drive shaft 23f is rotatably supported by bearing brackets 21b fixed to the front end of each vertical frame 21 of the tilt frame T. As can be seen in Figure 8, each bearing bracket 21b has its bracket base connected (e.g., bolted) to a front end wall plate 21a fixed (e.g., welded) to the front end of each vertical frame 21. In addition, rear end wall plates 21c are fixed (e.g., welded) to the rear ends of the left and right vertical frames 21, connecting them together.

The front end wall plate 21a releasably engages with the roller 33 and functions as a front stopper that determines the forward movement limit of the body B relative to the tilt frame T, while the rear end wall plate 21c releasably engages with the roller 33 and functions as a rear stopper that determines the backward movement limit of the body B relative to the tilt frame T.

21, a sensor gear 71 is concentrically fixed to the right end of the rotary drive shaft 23f. The sensor gear 71 has multiple sets 7G of dog teeth 7a, 7b, and 7c arranged at a constant circumferential interval t. As can be seen in FIG. 8, a proximity sensor 70 is fixed to the end wall panel 21a of the right-hand vertical frame 21, capable of detecting the approach of the dog teeth 7a, 7b, and 7c of the sensor gear 71. This proximity sensor 70 outputs a pulsed detection signal that alternates between on and off each time the dog teeth 7a, 7b, and 7c approach each other to the control device C. The control device C calculates the amount of rotation of the rotary drive shaft 23f, and therefore the sliding distance of the body B from the forward limit relative to the tilt frame T, based on, for example, the pulse width of the on signal (corresponding to the tooth width of the dog teeth 7a, 7b, and 7c) and the width of the off signal (corresponding to the pitch interval t between the dog teeth 7a, 7b, and 7c).

The sensor gear 71 and the proximity sensor 70 work together to form the rotation amount sensor RS.

In the sensor gear 71 of this embodiment, the multiple dog teeth 7a, 7b, and 7c described above are set to have tooth shapes and pitches such that the output pattern of the proximity sensor 70 that detects them is repeated periodically as the sensor gear 71 rotates and is different when the sensor gear 71 rotates forward and reverse. Meanwhile, the control device C can calculate the amount of rotation of the sensor gear 71 based on the output pattern of the proximity sensor 70 and determine the sliding direction of the body B.

More specifically, as can be seen in Figure 21, on the outer periphery of the sensor gear 71 of this embodiment, multiple dog tooth arrangement sets 7G are arranged side by side at the same pitch interval t, in which three dog teeth 7a, 7b, 7c with different tooth widths are arranged in order of tooth width size so that the arrangement pattern changes depending on whether the sensor gear 71 is rotating forward or reverse (in the illustrated example, the relationship between the size of the tooth widths of the dog teeth 7a, 7b, 7c is reversed).

The memory means of the control device C pre-stores the tooth widths of the dog teeth 7a, 7b, and 7c (i.e., the pulse widths of the ON signal pulses Pa, Pb, and Pc output by the sensor gear 71 according to the tooth widths) and the pitch interval t between the dog tooth array sets 7G. As is clear from Figure 22, the order of the ON signal pulses Pa, Pb, and Pc is reversed during forward rotation (a) and reverse rotation (b) of the rotary drive shaft 23f (and therefore the sensor gear 71) as the rotating shaft. Therefore, based on this stored information and the output pattern of the proximity sensor 70, the control device C can calculate both the amount of rotation (i.e., the sliding position of body B) and direction of rotation (i.e., the sliding direction of body B) of the sensor gear 71.

Furthermore, the control device C is equipped with a means for calculating and storing information on the shifting movement, i.e., the direction and amount of shifting, based on the output pattern of the proximity sensor 70 when the body B slides, i.e., shifts, without the operation of the remote control device R while the body B is temporarily stopped during the loading or unloading process. Based on this stored information, the control device C can determine whether or not to return the body B to the initial position of the temporary stop when the temporary stop is released, as described below, and if it determines that the body B should be returned, it can control the longitudinal drive device D to return the body B to the initial position of the temporary stop.

When making the above determination, if there is a risk that the amount of deviation of body B during the temporary stop will exceed a predetermined limit, thereby reducing the accuracy of process control after the temporary stop is released (for example, if body B moves too far rearward during the lowering process, making it impossible to lift the tilt frame T in the dump, or if it moves too far forward, causing the timing of lifting the dump to be earlier), then a determination is made to "return." If the control device C determines that there is no such risk, it does not return body B, but instead corrects the initial temporary stop position of body B stored at the time of the temporary stop, taking into account the deviation information (i.e., the direction and amount of deviation) based on the stored information regarding the deviation of body B during the temporary stop.

Thus, while the loading and unloading processes of the other vehicle V' are being performed, the control device C calculates the movement distance of the body B from the forward limit based on the amount of rotation detected by the rotation amount sensor RS, and switches the operation of the front and rear drive device D and the lift device L in a control manner described below when the movement distance reaches a predetermined distance. Furthermore, this operation switching also takes into account the detection results of the tilt angle sensor St, as described below.

Next, an example of body B will be described. Body B comprises a rectangular, flat body main body 31, the upper surface of which serves as a vehicle loading area for placing another vehicle V' (see Figure 1), a gate-shaped guard frame 36 erected at the upper front end of body main body 31, and a gate hinge 37 journaled at the lower end of body main body 31 so as to be able to rotate up and down. A clamp mechanism is installed between body main body 31 and gate hinge 37, which can rotate gate hinge 37 between an upright position and a reclined position and can hold it in the upright position; however, as this is well known, a functional description of this mechanism will be omitted.

Furthermore, a receiving frame 33 projects downward from the underside of the main body 31. The lower end of the receiving frame 33 is engageable with the guide roller 29 and is capable of sliding back and forth on the guide roller 29. A pair of receiving frames 33, one on the left and one on the right, are positioned corresponding to the guide roller 29, and extend linearly in the front-to-rear direction.

As can be seen in Figures 6 and 10, a pair of roller support brackets 32 (left and right) protrude downward from the underside of the front of the main body 31, and the upper parts of triangular movable support plates 34 are pivotally connected to these roller support brackets 32 so that they can rotate relative to one another. The rollers 33, which are housed in the vertical frame 21 and arranged side by side in the front and rear, are rotatably supported on the lower parts of these movable support plates 34, and contact-type proximity sensors 36 protrude downward between the pivot axes of the front and rear rollers 33.

Furthermore, as can be seen in Figures 6 and 8, a pair of left and right connecting brackets 35 for connecting the chains protrude downward from the underside of the front of the main body 31, laterally centerward of the roller support brackets 32. Then, one end and the other end of the chain 26 are pin-connected to the front and rear ends of a connecting block 38b, which is connected between each pair of connecting brackets 35 via a connecting pin 38p. Thus, in this embodiment, the connecting brackets 35, connecting block 38b, and connecting pin 38p constitute the connecting device J.

In addition, a ground contact roller 39 is rotatably supported at the rear end of the main body 31, and serves as the ground contact portion when the body B touches the ground in a tilted position with the rear downwards. This allows the rear end of the body B to move smoothly backward on the ground in this tilted position.

Furthermore, the sensor device S includes first to fourth sensors LSf, LSm, and LSr that are independent of the rotation amount sensor RS and can directly detect the sliding position of the body B.

The forward limit sensor LSf, acting as the first sensor, can detect the forward limit of the body B relative to the tilt frame T, and is composed of the proximity sensor 36 and a front dog df that can slidably engage with the detection portion of the proximity sensor 36. In other words, when the body B reaches the forward limit, the detection portion of the proximity sensor 36 simultaneously comes into sliding contact with the front dog df, and the proximity sensor 36 detects that the body B has reached the forward limit, and simultaneously outputs a detection signal to the control device C.

The intermediate position sensor LSm also functions as a second sensor capable of detecting the dump lift start position, where the tilt frame T is dumped upward, while the body B is sliding rearward to lower it from the tilt frame T to the ground. It is composed of a proximity sensor 36 and an intermediate dog dm that can slidably engage with the detection portion of the proximity sensor 36. In other words, at the same time that the body B reaches the dump lift start position, the detection portion of the proximity sensor 36 slides against the intermediate dog dm from its front end, and the proximity sensor 36 detects that the body B has reached the dump lift start position. At the same time, a detection signal is output to the control device C.

The intermediate position sensor LSm also functions as a third sensor that can detect the dump lowering start position, where the tilt frame T is dumped downward, while the body B is sliding forward from the ground to be loaded onto the tilt frame T. Like the second sensor, it is composed of a proximity sensor 36 and an intermediate dog dm. However, at the same time that the body B reaches the dump lowering start position, the detection portion of the proximity sensor 36 slides against the intermediate dog dm from its rear end, and the proximity sensor 36 detects that the body B has reached the dump lowering start position, and a detection signal is output to the control device C.

The fourth sensor, the reverse limit sensor LSr, can detect the reverse limit of the body B relative to the tilt frame T, and is composed of a proximity sensor 36 and a rear dog dr that can slidably engage with the detection portion of the proximity sensor 36. In other words, when the body B reaches the reverse limit, the detection portion of the proximity sensor 36 simultaneously comes into sliding contact with the rear dog dr, and the proximity sensor 36 detects that the body B has reached the reverse limit, and simultaneously outputs a detection signal to the control device C.

The front dog df is bolted to the front end of the tilt frame T (bearing bracket 21b in this embodiment), the middle dog dm to the middle section near the front end of the tilt frame T (bracket 21b' fixed to the underside of the middle section of the vertical frame 21 in this embodiment), and the rear dog dr to the rear end of the tilt frame T (bracket 21b" fixed to the underside of the rear of the vertical frame 21 in this embodiment), each of which is positionally adjustable.

The control device C operates the notification means 80 to issue a notification as described below when a detection position that should be detected by any of the first through fourth sensors LSf, LSm, and LSr is not detected by the rotation amount sensor RS but is detected by one of the sensors LSf, LSm, and LSr. Furthermore, the control device C also operates the notification means 80 to issue a notification as described below when a detection position that should be detected by any of the sensors LSf, LSm, and LSr is detected by the rotation amount sensor RS but not by one of the sensors LSf, LSm, and LSr.

Furthermore, if the rotation amount sensor RS detects a predetermined limit position where the body B has traveled a predetermined distance beyond the detection position that should be detected by any of the sensors LSf, LSm, or LSr, but the detection position that should be detected by that sensor is not detected by that sensor, the control device C will completely stop the front-rear drive device D and the lift device L, as described below.

The lift device L comprises a lift cylinder Lc, one end of which is pivotally connected (p1) to a cylinder support bracket 14 fixed to the subframe Fs, and a hoist arm 40, the middle of which is pivotally connected (p2) to the other end of the lift cylinder Lc. One end of the hoist arm 40 is pivotally connected (p3) to a first arm support bracket 15 fixed to the subframe Fs, and the other end is pivotally connected (p4) to a second arm support bracket 27 fixed to the tilt frame T.

The hoist arm 40 functions as a movable part whose angle changes more than the angle change of the tilt frame T when the lift device L is operated. A tilt angle sensor St is fixed to the hoist arm 40, which can detect the tilt angle of the hoist arm 40 as a movable part using only the sensor (i.e., without requiring a dog like a proximity sensor). This tilt angle sensor St changes its position relative to the vertical line (i.e., the direction of gravity) when the hoist arm 40 tilts, and is configured to detect the tilt angle of the hoist arm 40 by detecting the change in gravitational acceleration that accompanies this position change.

The hoist arm 40 of this embodiment comprises a pair of side plates 41 that sandwich the lift cylinder Lc from the left and right, and a top plate 42 that covers the space 43 sandwiched between the side plates 41 from above when the hoist arm 40 is in its traveling position. An inclination angle sensor St is installed on the inner surface of the hoist arm 40 facing the space 43, and the detection signal of the inclination angle sensor St is output to the control device C.

The hoist arm 40 also has a bottom plate 45 that covers the inclination angle sensor St and the surrounding space 43 from below and connects the left and right side plates 41 when in its traveling position (see Figures 11(A) and 12). This bottom plate 45 can prevent objects (e.g., pebbles, water, etc.) from splashing up from below when the vehicle is traveling from coming into contact with the inclination angle sensor St, and also functions as a reinforcing material for the hoist arm 40.

The control device C stores the detection value of the inclination angle sensor St when the tilt frame T, and therefore the hoist arm 40, is in the traveling position (see Figures 13(a) and 13(b) described below) as a reference value. It also stores the detection value of the inclination angle sensor St corresponding to the inclination angle of the hoist arm 40 when the tilt frame T is at a predetermined intermediate angle, e.g., 12 degrees (see Figures 13(c) to 13(e) described below), and the detection value of the inclination angle sensor St corresponding to the inclination angle of the hoist arm 40 when the tilt frame T is at its maximum inclination (see Figure 13(f) described below). The inclination angle of the hoist arm 40 is calculated by comparing the detection value with these reference values. From the calculated inclination angle, it can be determined that the tilt frame T has reached the predetermined intermediate angle (e.g., 12 degrees) or its maximum inclination angle. This detection result is also taken into account when switching the operation of the longitudinal drive device D and the lift device L in a control manner described below.

A proximity sensor 46 is fixed to the first arm support bracket 15 on the subframe Fs to detect when the hoist arm 40 is at its maximum tilt. This proximity sensor 46 detects this by engaging with a dog 42d fixed to the top plate 42 of the hoist arm 40 when the hoist arm 40 is at its maximum tilt, and outputs a detection signal to the control device C. The proximity sensor 46 and dog 42d thus constitute a maximum tilt detection sensor LSt.

A control panel (not shown) containing a control device C including a microcomputer capable of operating and controlling the front-rear drive unit D and the lift unit L is installed in the driver's cab of the vehicle transporter V. This control panel is equipped with, for example, a main switch SWm for turning the power on and off, a stop switch SWe for temporarily stopping the front-rear drive unit D and the lift unit L, a lowering switch SWo for commanding the lowering process of lowering the body B from the tilt frame T to the ground, and a loading switch SWi for commanding the loading process of loading the body B from the ground onto the tilt frame T, which can be operated as desired. These switches SWm, SWe, SWo, and SWi work together to form the remote control device R described above, and are each connected to the control device C as shown in FIG. 15.

In particular, in this embodiment, the unloading switch SWo is configured so that the unloading process is executed only when it is pressed, and the unloading process is paused if the unloading switch SWo is released during execution. Similarly, the loading switch SWi is configured so that the loading process is executed only when it is pressed, and the loading process is paused if the loading switch SWi is released during execution. Therefore, simply releasing the unloading switch SWo or loading switch SWi while the process is in progress can temporarily halt the unloading process or loading process without relying on the stop switch SWe. Furthermore, if the unloading switch SWo or loading switch SWi is pressed again while the unloading process or loading process is paused as described above, the unloading process or loading process can be resumed.

As a modification of the remote control device R in the above embodiment, the unloading switch SWo may be configured so that when pressed, the unloading process begins, and the unloading process continues to the end even if the switch is subsequently released. The loading switch SWi may also be configured so that when pressed, the loading process begins, and the loading process continues to the end even if the switch is subsequently released. In this modification, pressing the stop switch SWe while the unloading or loading process is in progress can temporarily halt the unloading or loading process, but pressing the unloading switch SWo or loading switch SWi while the process is paused can resume the unloading or loading process.

The control device C is also connected to the various sensors RS, LSf, LSm, LSr, and St mentioned above, and receives their respective detection signals. The control device C is also connected to an electromagnetic motor drive hydraulic control valve Vm provided in the on-board hydraulic control circuit to rotate the motor M forward and reverse, an electromagnetic lift cylinder drive hydraulic control valve Vc provided in the on-board hydraulic control circuit to extend and retract the lift cylinder Lc, and a warning lamp 80 (see Figure 15) as a warning means for notifying of malfunctions of the sensors.

In addition, each of the hydraulic control valves Vm and Vc is equipped with a conventional operating unit (not shown) that allows a worker to manually operate the valves independently of the remote control device R or the control device C, for example, during maintenance of the vehicle transporter V.

Sensor malfunctions can occur in the following ways. For example, with the rotation amount sensor RS, some of the dog teeth on the sensor gear 71 may be missing, or the proximity sensor 70 may fail to detect some of the dog teeth (i.e., skipped teeth) due to vibrations or shocks from the tilt frame T. In addition to a malfunction of the proximity sensor 70 itself, it is also possible that the proximity sensor 70 may be misaligned, causing it to be unable to detect the dog teeth or to continue detecting them.

On the other hand, possible malfunctions of the forward limit sensor LSf, intermediate position sensor LSm, and reverse limit sensor LSr include, for example, a malfunction of the proximity sensor 36 itself, a misalignment of the proximity sensor 36 mounting position, or deformation or misalignment of the dogs df, dm, and dr, which can cause the proximity sensor 36 to be unable to detect the dogs df, dm, and dr, or to detect them in a position other than their normal position.

In addition, as the notification means, a notification sound generator such as a notification buzzer or speaker may be used instead of or in addition to the notification lamp 80. The notification means may also be provided on the control panel or outside the control panel.

Furthermore, the control panel may be provided in addition to the driver's cab, or in a suitable location on the vehicle exterior panel outside the driver's cab, or on the body B. Furthermore, at least the switches and notification means (notification lamp 80) on the control panel may be provided on a wired or wireless remote control device that can be separated from the control panel.

Next, the operation of the above embodiment will be explained.

In the vehicle loading device A of the vehicle transporter V, as shown in Figures 1 and 13(a), in its traveling position, a tilt frame T is mounted in a prone position on the subframe Fs, and a body B is mounted on the tilt frame T in a prone position at the forward limit. Another vehicle V' loaded on the body B can then be transported by the vehicle transporter V.

The process of lowering body B (and therefore the other vehicle V' on it) from this traveling position to the ground is shown in chronological order in Figure 13.

To briefly outline the process, first, the forward rotation of the longitudinal drive device D causes the body B to slide rearward from the forward limit relative to the tilt frame T. When this sliding causes the body B to travel a predetermined distance from the forward limit, as shown in Figure 13(b), the rotation amount sensor RS detects this, and based on the detection result, the control device C stops the longitudinal drive device D and uses the lift device L to dump the tilt frame T upward together with the body B.

The reason for moving the body B backward a predetermined distance before dumping and raising the tilt frame T is to shift the center of gravity of the body B rearward, thereby reducing the load on the lift device L when dumping and raising the tilt frame T around the guide rollers 12.

Then, as shown in Figure 13(c), when the tilt angle sensor St detects that the tilt angle of the tilt frame T has reached a predetermined intermediate angle, the control device C stops the lift device L based on the detection result and resumes the forward rotation of the front-rear drive device D, causing the body B to slide rearward again.

As body B slides rearward, the rear end of body B (more specifically, the ground contact roller 39) touches the ground as shown in Figure 13(d), and body B then assumes a supported configuration in which it is supported by both the ground and the tilt frame T, and body B slides further rearward in this supported configuration.

When the body B reaches the rearward limit relative to the tilt frame T as shown in Figure 13(e), the rearward limit sensor LSr detects this, and based on this detection result, the control device C stops the front-rear drive device D and causes the lift device L to dump the tilt frame T upward again. Then, when the tilt angle sensor St detects that the tilt frame T has reached its maximum tilt angle as shown in Figure 13(f), the control device C stops the lift device L based on this detection result. At this time, the ground contact roller 52 at the rear end of the tilt frame T is placed in a ground contact state, as can be seen in Figure 14(B).

Note that at any stage in Figures 13(d) to (f) above, it is possible to load or unload another vehicle V' onto or from body B. When loading or unloading, the gate hinge 37 at the rear end of body B is left open, and in this case, the gate hinge 37 functions as a gangway to allow the other vehicle V' to enter smoothly. In contrast, when performing the steps in Figures 13(d) to (f) without loading or unloading another vehicle V', the gate hinge 37 is kept in the closed position, as leaving it open could cause it to rub against the ground and be damaged.

In particular, in the state shown in Figure 13(f), the body B, which is at its rearmost position relative to the tilt frame T, is in a substantially horizontal ground contact state, allowing another vehicle V' to smoothly drive onto the body B.

The loading process from the state shown in Figure 13(f) to the state shown in Figure 13(a) can be carried out by reversing the unloading process described above.

More specific control aspects of the unloading process and loading process outlined above will be explained using the flowcharts in Figures 16 to 19. Here, the flowcharts in Figures 16 and 17 correspond to a first control example in which proximity sensors (i.e., forward limit sensor LSf, intermediate position sensor LSm, and reverse limit sensor LSr) are used in addition to the rotation amount sensor RS to detect the forward/backward sliding position of the body B relative to the tilt frame T. The flowcharts in Figures 18 and 19 correspond to a second control example in which only the rotation amount sensor RS is used to detect the forward/backward sliding position of the body B relative to the tilt frame T, without also using proximity sensors (i.e., forward limit sensor LSf, intermediate position sensor LSm, and reverse limit sensor LSr).

The amount of rotation detected by the rotation amount sensor RS can be converted into the distance traveled by body B from its forward limit. In the following explanation of the control mode, this distance will be referred to simply as the "detection distance of the rotation amount sensor RS," and the figures used here are in millimeters.

In the case of an embodiment specialized in the second control example, the proximity sensors (that is, the forward limit sensor LSf, the intermediate position sensor LSm, and the reverse limit sensor LSr) are omitted from the control block diagram shown in FIG.
[Unloading process according to the first control example]
When the main switch SWm on the control panel is pressed and then the lowering switch SWo is pressed, the motor M of the front and rear drive unit D starts rotating forward in step S1, causing the body B to slide rearward. Next, in step S2, it is determined whether the detected distance of the rotation amount sensor RS is 1100 or more, and if the result is YES, the process proceeds to step S3, where it is determined whether the intermediate position sensor LSm (second sensor) is ON.

If the answer is yes in step S3, proceed to step S4 to determine whether the detected distance of the rotation amount sensor RS has reached the normal distance of 1,300. If the answer is yes, proceed to step S5 to cancel the alarm operation, and then proceed to step S6 to stop the motor M and extend the lift cylinder Lc. Next, proceed to step S7 to determine whether the detected angle of the tilt angle sensor St has reached a predetermined intermediate angle (for example, the tilt angle of body B is 12 degrees). If the answer is yes, proceed to step S8 to stop the lift cylinder Lc and rotate the motor M forward again to slide body B backward again. Next, proceed to step S9 to determine whether the detected distance of the rotation amount sensor RS is 4,200 or more. If the answer is yes, proceed to step S10 to determine whether the reverse limit sensor LSr (fourth sensor) is ON.

If the answer is yes in step S10, proceed to step S11 to determine whether the distance detected by the rotation amount sensor RS has reached the normal distance of 4,400. If the answer is yes, proceed to step S12 to cancel the alarm, and then proceed to step S13 to stop the motor M and extend the lift cylinder Lc again. Next, proceed to step S14 to determine whether the angle detected by the tilt angle sensor St has reached the maximum tilt angle. If the answer is yes, proceed to step S15 to stop the lift cylinder Lc and end the process.

However, if the answer is NO in step S4, proceed to step S21, activate the alarm means 80, and correct the detection distance of the rotation amount sensor RS to the normal distance of 1300, after which return to step S6.

If the answer is NO in step S11, proceed to step S22, activate the alarm means 80, and correct the detected distance of the rotation amount sensor RS to the normal distance of 4,400, after which return to step S13.

If the answer is no in step S14, proceed to step S23 to determine whether the maximum tilt detection proximity sensor LSt is on. If the answer is yes in step S23, proceed to step S15; if the answer is no, return to step S14.

If the answer is no in step S3, proceed to step S31 to determine whether the detected distance of the rotation amount sensor RS has reached the normal distance of 1,300. If the answer is yes, proceed to step S32 to activate the alarm means 80, and then proceed to step S33. In step S33, it is determined whether the detected distance of the rotation amount sensor RS has reached the limit distance of 1,500. If the answer is yes, proceed to step S34 to completely stop the motor M and lift cylinder Lc. Note that if the answer is no in both steps S31 and S33, return to step S3.

Also, if the answer is NO in step S10, proceed to step S36 to determine whether the detection distance of the rotation amount sensor RS has reached the normal distance of 4400. If the answer is YES, proceed to step S32 to activate the alarm means 80, then proceed to step S37 to activate the alarm means 80, and then return to step S13. Also, if the answer is NO in step S36, return to step S10.

In the first control example of the unloading process described above, after step S32, the process proceeds to step S33, where it is determined whether a full stop is required. However, as another control example (not shown), it is also possible to proceed from step S32 to step S6 without proceeding to step S33. In this other control example, even if it is determined in step S3 that the intermediate position sensor LSm has not detected anything, the notification means 80 is activated in step S32 in response to the rotation amount sensor RS detecting the normal distance of 1,300 in step S31, and then the process immediately proceeds to step S6, thereby continuing the subsequent processing procedure. Furthermore, steps S2 and/or S9 may be omitted.
[Loading process according to the first control example]
When the main switch SWm on the control panel is pressed and then the loading switch SWi is pressed, in step S101 the lift cylinder Lc begins to retract, dumping the tilt frame T downward. Next, in step S102, it is determined whether the tilt angle sensor St has reached an intermediate opening (for example, the tilt angle of the body B is 12 degrees). If the answer is YES, the process proceeds to step S103, where the lift cylinder Lc is stopped and the motor M of the front-rear drive device D is rotated in the reverse direction to slide the body B forward relative to the tilt frame T.

Next, proceed to step S104 to determine whether the detected distance of the rotation amount sensor RS is 1500 or less. If the answer is yes, proceed to step S105 to determine whether the intermediate position sensor LSm (second sensor) is ON. If the answer is yes in step S105, proceed to step S106 to determine whether the detected distance of the rotation amount sensor RS has reached the normal distance of 1300. If the answer is yes, proceed to step S107 to cancel the alarm operation, and then proceed to step S108 to stop the motor M and retract the lift cylinder Lc.

Next, proceed to step S109 to determine whether the angle detected by the tilt angle sensor St has reached the minimum angle (e.g., 0 degrees). If the answer is yes, proceed to step S110 to stop the lift cylinder Lc and reverse the motor M again to slide the body B forward again. Then, proceed to step S111 to determine whether the distance detected by the rotation amount sensor RS has fallen below 200, just before the forward movement limit. If the answer is yes, proceed to step S112 to determine whether the forward movement limit sensor LSf (first sensor) is ON.

If the answer is yes in step S112, proceed to step S113, stop the lift cylinder Lc, and the process ends.

However, if the answer is NO in step S106, proceed to step S121, activate the alarm means 80, and correct the detected distance of the rotation amount sensor RS to the normal distance of 1300, after which return to step S108.

Also, if the answer is NO in step S105, proceed to step S131 to determine whether the detected distance of the rotation amount sensor RS is less than the normal distance of 1,300. If the answer is YES, proceed to step S132 to activate the alarm means 80, and then proceed to step S133. In step S133, it is determined whether the detected distance of the rotation amount sensor RS is less than the limit distance of 1,000. If the answer is YES, proceed to step S134 to completely stop the motor M and lift cylinder Lc. Note that if the answer is NO in both steps S131 and S133, return to step S105.

In the above loading process, after step S132, the process proceeds to step S133 where it is determined whether a full stop is required. However, as another control example (not shown), it is also possible to proceed from step S132 to step S108 without proceeding to step S133. In this other control example, even if it is determined in step S105 that the intermediate position sensor LSm has not detected anything, the notification means 80 is activated in step S132 in response to the rotation amount sensor RS detecting the normal distance 1,300 in step S131, and then the process immediately proceeds to step S108, thereby continuing the subsequent processing procedures. Furthermore, steps S104 and/or S111 may be omitted.
[Unloading process according to the second control example]
When the main switch SWm on the control panel is pressed and then the lowering switch SWo is pressed, the motor M of the longitudinal drive unit D starts rotating in the forward direction in step S201, sliding the body B rearward. Next, the program proceeds to step S202, where it is determined whether the distance detected by the rotation amount sensor RS has reached the normal distance of 1,300. If the result is YES, the program proceeds to step S203, where the motor M is stopped and the lift cylinder Lc is extended.

Next, proceed to step S204 to determine whether the angle detected by the tilt angle sensor St has reached a predetermined intermediate angle (for example, the tilt angle of body B is 12 degrees). If the answer is yes, proceed to step S205 to stop the lift cylinder Lc and rotate the motor M forward again to slide the body B backward again. Then, proceed to step S206 to determine whether the distance detected by the rotation amount sensor RS has reached the normal distance of 4400. If the answer is yes, proceed to step S207 to stop the motor M and extend the lift cylinder Lc again.

Thereafter, the process proceeds to step S208, where it is determined whether the angle detected by the tilt angle sensor St has reached the maximum tilt angle, and if so, the process proceeds to step S209, where the lift cylinder Lc is stopped and the process ends.
[Loading process according to the second control example]
When the main switch SWm on the control panel is pressed and then the loading switch SWi is pressed, in step S211 the lift cylinder Lc begins to retract, dumping the tilt frame T downward. Next, in step S212, it is determined whether the tilt angle sensor St has reached an intermediate opening (for example, the tilt angle of the body B is 12 degrees). If the answer is YES, the process proceeds to step S213, where the lift cylinder Lc is stopped and the motor M of the front-rear drive device D is rotated in the reverse direction to slide the body B forward relative to the tilt frame T.

Next, proceed to step S214 to determine whether the distance detected by the rotation amount sensor RS has reached the normal distance of 1,300. If the answer is yes, proceed to step S215 to stop the motor M and extend the lift cylinder Lc again.

Next, the flow proceeds to step S216 to determine whether the angle detected by the tilt angle sensor St has reached a minimum angle (e.g., 0 degrees). If the answer is YES, the flow proceeds to step S217 to stop the lift cylinder Lc and rotate the motor M in the reverse direction again to slide the body B forward again. Thereafter, the flow proceeds to step S218 to determine whether the distance detected by the rotation amount sensor RS has reached 0. If the answer is YES, the flow proceeds to step S219 to stop the lift cylinder Lc and the flow ends.
[Example of control to deal with body misalignment during temporary stop of process]
However, if the body B should shift during the unloading or loading process while the process is temporarily stopped by the remote control device R, the shifting movement may affect the control when the process is resumed by remote control operation after the temporary stop is released. Therefore, in this embodiment, an example of control by the control device C corresponding to the body shifting movement is executed, as shown in the flowchart of Figure 20. Next, this control example will be described.

First, when an operator stops operating the remote control to temporarily suspend the unloading or loading process, the process proceeds to step S301, where the process being performed (and therefore body B) is temporarily suspended. Next, the process proceeds to step S302, where it is determined whether remote control operation has been resumed to release the suspension. If not, the process proceeds to step S303, where it is determined whether body B has shifted during the suspension. If not, the process returns to step S301.

If it is determined in step S303 that body B is shifting during the temporary stop, the process proceeds to step S304, where the output pattern of the rotation amount sensor RS (proximity sensor 70) during the shifting movement is read into the storage means of control device C, and then the process proceeds to step S305. In step S305, it is determined whether body B has finished shifting. If it has, the process returns to step S301; if it has not, the process returns to step S304, where the reading of the output pattern continues.

Furthermore, if it is determined in step S302 that remote control operation has resumed to release the pause, the process proceeds to step S306, where it is determined whether any deviation of body B occurred during the pause (i.e., whether there was a reading history of the output pattern during the pause), and if deviation occurred, the process proceeds to step S307, where control device C calculates deviation information of body B (i.e., the direction and amount of deviation of body B) based on the reading history of the output pattern during the pause.

Next, the process proceeds to step S308, where a determination is made based on the calculation results of the deviation movement information as to whether body B needs to be returned to its original pause position (i.e., the initial position of the pause) when the pause is released. If it is determined that body B does not need to be returned, the process proceeds to step S309. Then, in this step S309, the original pause position of body B stored in the memory means of control device C is corrected based on the calculation results of the deviation movement information so that it is corrected to the actual position (i.e., the position after the deviation movement). Then, the process proceeds to step S310, where the process that was paused is resumed.

However, if it is determined in step S308 based on the calculation results of the deviation movement information that it is necessary to return body B to the original pause position (i.e., the initial position of the pause), the process proceeds to step S311. In step S311, the longitudinal drive device D (motor M) is operated and controlled based on the calculation results of the deviation movement information to return body B to the original pause position, and after this return movement, the process proceeds to step S310, where the process currently being paused is resumed.

In addition, in step S311, while body B is returning to its original position, the notification means 80 or another notification means may be used to notify or warn the user of this.

In the embodiment described above, the longitudinal drive device D, which forcibly slides the body B relative to the tilt frame T, has a rotary drive shaft 23f as a rotational shaft for driving the chain 26, and the rotation amount of the rotary drive shaft 23f is detected by a rotation amount sensor RS. The movement distance of the body B from the forward limit is calculated based on this detected rotation amount, and the operation of the longitudinal drive device D and the lift device is switched when this movement distance reaches a predetermined distance. Therefore, the movement distance of the body B from the forward limit can be precisely detected by the rotation amount sensor RS, and operation can be switched appropriately based on the detection results.

Compared to conventional structures where multiple limit switches (proximity switches) are used to pinpoint multiple operation switch positions, this effectively reduces the risk of missed detection due to vibrations or impacts that the tilt frame T receives while the body B is sliding (and therefore the risk that the above-mentioned operation switch will not be executed). For example, this is effective in preventing inconveniences such as missed detection during the unloading operation of body B, causing the body B to slide backward to the reverse limit without dumping, or missed detection during the loading operation of body B, causing the body B to slide forward to the forward limit while still in the dumped state.

In addition to the rotation amount sensor RS, the sensor device S of this embodiment also includes a forward limit sensor LSf as a first sensor that detects the forward limit of the body B, a middle position sensor LSm as a second sensor that detects the dump lift start position when the body B is slid rearward to be lowered, a middle position sensor LSm as a third sensor that detects the dump lowering start position when the body B is slid forward to be loaded from the ground, and a backward limit sensor LSr as a fourth sensor that detects the backward limit of the body B.

If a detection position that should be detected by any of the first through fourth sensors LSf, LSm, and LSr is not detected by the rotation amount sensor RS but is detected by that sensor, the control device C activates the alarm means 80, as is clear from the first control example (step S21 in FIG. 16 and step S121 in FIG. 17). This causes an alarm to be issued in situations where the detection results of any of the first through fourth sensors LSf, LSm, and LSr and the rotation amount sensor RS do not match, particularly in situations where the detection position is not detected by the rotation amount sensor RS but is detected by any of the first through fourth sensors LSf, LSm, and LSr, making it easier to find malfunctions in the rotation amount sensor RS.

Furthermore, as is clear from the first control example (step S32 in FIG. 16, step S132 in FIG. 17), if the above-mentioned detection position is detected by the rotation amount sensor RS but not by any of the above-mentioned sensors LSf, LSm, or LSr, the control device C will activate the alarm means 80 to issue an alarm. This will cause an alarm to be issued in situations where the detection results of any of the first through fourth sensors LSf, LSm, or LSr and the rotation amount sensor RS do not match, particularly in situations where the above-mentioned detection position is detected by the rotation amount sensor RS but not by any of the first through fourth sensors LSf, LSm, or LSr, making it easier to find a malfunction in any of the first through fourth sensors LSf, LSm, or LSr.

In particular, if the above-mentioned detection position is not detected by any of the first through fourth sensors LSf, LSm, and LSr, but the rotation amount sensor RS detects a predetermined limit position where the body B has traveled a predetermined distance beyond the detection position, as is clear from the first control example (steps S33 and S34 in FIG. 16, steps S133 and S134 in FIG. 17), it is determined that a malfunction has occurred in either one of the first through fourth sensors LSf, LSm, and LSr or the rotation amount sensor RS, and the longitudinal drive unit D and the lift unit are automatically stopped. This makes it possible to automatically stop the longitudinal sliding movement of the body B and the tilting movement of the tilt frame T, even in situations where, for example, one of the first through fourth sensors LSf, LSm, and LSr misses the detection position and the body B slides excessively, thereby further improving work safety.

In this embodiment, the lift device L has a hoist arm 40 as a movable part whose angle changes more than the angle change of the tilt frame T when it is operated. The hoist arm 40 is equipped with a tilt angle sensor St that detects the tilt angle of the hoist arm 40 based on changes in gravitational acceleration. When the control device C detects from the angle detected by the tilt angle sensor St that the tilt angle of the tilt frame T is a predetermined angle, it switches the operation of the front-rear drive device D and the lift device.

As a result, when the tilt frame T is dumped by the lift device L, the tilt angle sensor St can detect the tilt angle of the hoist arm 40, which changes more than the angle change of the tilt frame T, based on changes in gravitational acceleration. This detected angle makes it possible to accurately determine whether the tilt angle of the tilt frame T is the specified angle at which the above-mentioned operation switching should be performed. Furthermore, because the tilt angle sensor St only needs to be attached to the hoist arm 40, installation is significantly simplified compared to conventional structures using proximity sensors with two components, a dog and a sensor body, and fine adjustment of the two components is also unnecessary. As a result, the advantages of the tilt angle sensor St, which utilizes changes in gravitational acceleration, are utilized while overcoming its drawbacks, making it possible to detect the tilt angle of the tilt frame T with sufficient accuracy.

Furthermore, the hoist arm 40 of this embodiment is equipped with a pair of side plates 41 that sandwich the lift cylinder from the left and right, and a top plate 42 that covers the space 43 sandwiched between the side plates 41 from above when the hoist arm 40 is in its traveling position. The tilt angle sensor St is installed on the inner surface of the hoist arm 40 facing the space 43, so the top plate 42 and both side plates 41, which are used to ensure the strength of the hoist arm 40, can also be used as rain covers for the tilt angle sensor St. This eliminates the need for a dedicated rain cover to cover the tilt angle sensor St, resulting in cost savings.

Furthermore, as can be seen in Figures 6 and 7, the vertical frame 21 of the tilt frame T is mounted on guide rollers 29 journaled at the rear of the subframe Fs and on the horizontal frame at the front of the subframe Fs, respectively, so that the tilt frame T is prone to vibration and impact, and therefore its tilt angle is also prone to fluctuation. In contrast, the lift cylinder Lc and hoist arm 40 of the lift device L have their base ends pivotally connected p1 and p3 to the subframe Fs, so their respective tilt angles are less likely to fluctuate. Therefore, the tilt angle sensor St fixed to the hoist arm 40 can detect the tilt angle more accurately than an inclination angle sensor with a proximity sensor attached to the tilt frame T.

In this embodiment, the longitudinal drive device D, which forcibly slides the body B relative to the tilt frame T, has a rotary drive shaft 23f for driving the chain 26, and a rotation amount sensor RS, which can detect the rotation amount of the rotary drive shaft 23f, is equipped with a sensor gear 71 having multiple dog teeth 7a, 7b, and 7c on its outer periphery and rotating in conjunction with the rotary drive shaft 23f, and a proximity sensor 70 that can detect the dog teeth 7a, 7b, and 7c. In particular, the multiple dog teeth 7a, 7b, and 7c are set to have a tooth shape and pitch such that the output pattern of the proximity sensor 70 that detects them is repeated cyclically as the sensor gear 71 rotates and is different during forward and reverse rotation of the sensor gear 71. Based on the output pattern of the proximity sensor 70, the control device C can calculate the rotation amount of the rotary drive shaft 23f, i.e., the sensor gear 71 (i.e., the amount of sliding of the body B), and can also calculate and determine the direction of rotation (i.e., the direction of sliding of the body B).

If, for some reason, body B deviates from the paused position while the process is temporarily stopped by remote control during the unloading or loading process of body B, control device C can accurately recognize information about the deviation of body B from the initial paused position (i.e., the direction and amount of deviation) based on the characteristic output pattern of proximity sensor 70. Therefore, by utilizing this deviation information, it is possible to improve the accuracy of process control after the pause is released. Next, the effects of this will be explained in detail.

In other words, in this embodiment, multiple dog teeth 7a, 7b, and 7c with different tooth widths are arranged on the outer periphery of the sensor gear 71 so that their arrangement order differs between forward and reverse rotation of the sensor gear 71 (see Figure 21). Therefore, the arrangement pattern, i.e., the order, of pulses Pa, Pb, and Pc with different pulse widths output by the proximity sensor 70 in response to the differences in tooth width of each dog tooth 7a, 7b, and 7c differs between forward and reverse rotation of the sensor gear 71, as can be seen in Figure 22 (i.e., the order is reversed). The control device C can then recognize the above-mentioned misalignment information of the body B by utilizing the fact that the arrangement pattern of pulses with different pulse widths output by the proximity sensor 70 in response to the differences in tooth width of each dog tooth 7a, 7b, and 7c differs between forward and reverse rotation. Moreover, the accurate recognition of the above-mentioned misalignment information can be achieved with a simple structure that simply differs the tooth widths of the dog teeth 7a, 7b, and 7c and arranges them in a specific pattern, contributing to cost savings.

Furthermore, in the embodiment, the control device C has storage means for storing information on the shifting movement (i.e., the direction and amount of the shifting movement, specifically the direction and amount of rotation of the rotary drive shaft 23f) in the event that the body B shifts during the pause in the above process without the operation of the remote control device R. Based on this storage, it is possible to determine whether or not to return the body B to the initial pause position when the pause is released (see step S308 above), and if it is determined that the body B should be returned, it is possible to control the longitudinal drive device D so that the body B returns to the initial pause position (see step S311 above).

In this way, if body B shifts without remote control operation during the above-mentioned temporary stop, control device C can not only recognize information about the above-mentioned shifting movement of body B based on the characteristic output pattern of proximity sensor 70, but also determine, based on that recognition information, whether or not to return body B to the initial temporary stop position when the temporary stop is released. Furthermore, if it is determined that body B should be returned, body B can be easily and accurately returned to the initial temporary stop position, thereby improving the control accuracy of the process that resumes after the temporary stop is released.

In the above embodiment, multiple sets (eight sets) of dog tooth arrangement sets 7G were shown, each set having three dog teeth 7a, 7b, and 7c with different tooth widths arranged in different arrangement patterns (i.e., arranged in order of tooth width size) at the same pitch interval t, with the sensor gear 71 rotating in the forward and reverse directions. However, the number of dog teeth per set of dog tooth arrangement sets 7G may be four or more. Alternatively, the number of dog tooth arrangement sets 7G provided on one sensor gear 71 is not limited to the embodiment, and in particular in the case of a dog tooth arrangement set 7G having a large number of dog teeth with different tooth widths, the number may be fewer than in the embodiment, for example, just one set.

Furthermore, the output pulse signal of the sensor gear 71 that detects the multiple dog teeth 7a, 7b, and 7c may be an output pattern consisting of only ON signals with different pulse widths, as in the above embodiment, or may be an output pattern consisting of only OFF signals with different pulse widths, as shown in Figure 23(a').

Alternatively, the output pattern may be a combination of an ON signal and an OFF signal, as shown in Figure 23(a"), in which case the number of dog teeth with different tooth widths per dog tooth arrangement set 7G can be two, as in the example shown. In other words, by combining the pulse width of the ON signal (the "large" and "small" widths in the example of Figure 23(a")) with the pulse width of the OFF signal (similarly the "medium" width), it is possible to distinguish and recognize the output pattern when the sensor gear 71 is rotating forward and the output pattern when it is rotating reversely, and to determine the direction of rotation, even if there are two dog teeth with different tooth widths.

Now, Figure 24 shows a modified example of the sensor gear 71 of the above embodiment. In place of the dog tooth arrangement set 7G of the sensor gear 71 of the above embodiment, which consists of multiple sets of dog teeth 7a, 7b, 7c with different tooth widths, this modified example uses sets of small dog teeth 7a', 7b', 7c' with the same tooth width, numbered according to the tooth width size of the dog teeth 7a, 7b, 7c, 7Ga, 7Gb, 7Gc.

In this modified example, the groups 7Ga, 7Gb, and 7Gc of small dog teeth 7a', 7b', and 7c' are arranged at regular intervals t" in the circumferential direction. In particular, in the small dog tooth groups 7Ga and 7Gb, each of which has a plurality of small dog teeth 7a' and 7b', the small dog teeth 7a' and 7b' are arranged at the same small pitch intervals t' that are smaller than the regular intervals t". The rest of the configuration of this modified example is the same as that of the vehicle transporter V in the above-described embodiment.

In this modified example, the control device C can recognize information about the deviation of body B from the temporary stop position (i.e., the direction and amount of deviation) by taking advantage of the fact that the proximity sensor 70 detects the small dog teeth 7a', 7b', 7c' of each group 7Ga, 7Gb, 7Gc and outputs small pulses Pa', Pb', Pc' in short bursts (in other words, the number of output pulses corresponding to each small dog tooth group 7Ga, 7Gb, 7Gc) and the difference in the number of output pulses corresponding to each small dog tooth group 7Ga, 7Gb, 7Gc when the sensor gear 71 is rotating forward and reverse, as is clear from Figure 24.

Although an embodiment of the present invention has been described above, the present invention is not limited to this embodiment, and various embodiments can be implemented within the scope of the present invention.

For example, in the above embodiment, the control device C activates the alarm means 80 in either of the following cases: a first case in which a detection position that should be detected by any of the first to fourth sensors LSf, LSm, LSr is detected by one of the sensors LSf, LSm, LSr but not by the rotation amount sensor RS; and a second case in which a detection position is detected by the rotation amount sensor RS but not by one of the sensors LSf, LSm, LSr. However, in the present invention, the alarm may be activated in the first case but not in the second case, or conversely, the alarm may be activated in the second case but not in the first case.

In addition, in the above embodiment, the intermediate position sensor LSm was shown as being used both as the second sensor (i.e., a sensor capable of detecting the dump lift start position where the tilt frame T is dumped upward during the sliding process of the unloading process) and the third sensor (i.e., a sensor capable of detecting the dump lowering start position where the tilt frame T is dumped downward during the sliding process of the loading process), but the second and third sensors may also be implemented as separate sensors.

In addition, the above embodiment uses the forward limit sensor LSf as the first sensor, the intermediate position sensor LSm as the second and third sensors, and the reverse limit sensor LSr as the fourth sensor. However, it is also possible to implement another embodiment in which all of these sensors LSf, LSm, and LSr are omitted (i.e., the second control example shown in Figures 18 and 19), or to implement yet another embodiment in which only at least one of these sensors LSf, LSm, and LSr is used.

In the above embodiment, the rotary drive shaft 23f, which is arranged coaxially with the motor M and directly connected to it, is used as the rotary shaft for detecting the amount of rotation by the rotation amount sensor RS. However, the rotary shaft of the present invention may be a rotary drive shaft 23f that is not arranged coaxially with the motor M (i.e., a rotary drive shaft that rotates in conjunction with the motor via an interlocking mechanism), or may be another rotary shaft that rotates in conjunction with at least the chain 26, such as a rotary driven shaft 23r located at the rear end of the tilt frame T, or an intermediate shaft with an intermediate sprocket that is located midway between the front and rear of the tilt frame T and rotates in conjunction with the chain 26.

In addition, in the above embodiment, an example was given of a vehicle transporter V in which the detection of the slide position of the body B, which is necessary for controlling the operation switching of the front and rear drive device D and the lift device T in controlling the unloading process and the loading process, is performed either solely by a rotation amount sensor R that detects the amount of rotation of the rotary drive shaft 23f (sensor gear 71) of the front and rear drive device D, which serves as a rotary shaft that rotates in conjunction with the chain 26, or in combination with multiple limit switches (first to fourth sensors LSf, LSm, LSr) that can directly detect that the body B has reached a predetermined slide position. In contrast, the present invention can also be applied to a vehicle transporter (see Patent Document 1) that uses only the multiple limit switches (first to fourth sensors LSf, LSm, LSr) to detect the sliding position of body B for the above-mentioned operation switching, so that it can respond to shifting movement of body B during temporary stoppages in the process. Even in this case, shifting movement information (shifting direction and amount of shifting movement of body B) can be calculated and acquired based on the output pattern of the rotation amount sensor R (proximity sensor 70) of the present invention, as in the above embodiment.

In this case, a return command switch is connected to control device C, which commands body B to return to the stop position it was in when it was first paused (i.e., before the shifting movement). For example, if an operator recognizes that body B has shifted during a temporary stop of the process and determines that automatic return is necessary, the operator presses this return command switch, which causes control device C to control the automatic return of body B to the stop position it was in when it was first paused (a movement process for automatic return similar to step S311 above). After this automatic return, the paused process is resumed by remote control operation of remote control device R. On the other hand, if an operator recognizes that body B has shifted during a temporary stop of the process but determines that automatic return is not necessary, the paused process can be resumed by remote control operation without pressing the return command switch.

In another embodiment of the present invention, a second sensor gear having dog teeth of the same tooth width and at an equal pitch may be provided on the rotating shaft (e.g., rotary drive shaft 23f) of the present invention, separate from the sensor gear 71. The dog teeth of this second sensor gear may be detected by a second proximity sensor provided separately from proximity sensor 70, allowing the second sensor gear and second proximity sensor to detect that the rotating shaft (23f) is rotating at a constant speed. In this alternative embodiment, if the body B shifts without remote control operation during a temporary stop of the unloading or loading process, and particularly if the second sensor gear and second proximity sensor can detect that the rotating shaft (23f) is rotating at a constant speed at that time, the shift information of the body B (i.e., the direction and amount of shift) can be more accurately and precisely determined by taking into account the result of determining the direction of shift of the body B (i.e., the direction of rotation of the rotating shaft) using the above-mentioned technical features of the present invention.

B. Body C. Control device D. Longitudinal drive device F. Vehicle body L. Lift device R. Remote control device RS. Rotation amount sensor S. Sensor device T. Tilt frame V. Vehicle transport vehicle V'. Other vehicle 23f. Rotation drive shaft 26 as a rotation shaft. Chain

Claims (3)

a tilt frame (T) supported at the rear of a vehicle body (F) so as to be capable of being dumped and so as to be movable forward and backward; a lift device (L) for forcibly dumping the tilt frame (T); a body (B) having a vehicle loading section on which another vehicle (V') can be placed and slidable in the forward and backward direction on the tilt frame (T); a chain-transmitted longitudinal drive device (D) having a chain (26) fixed to the body (B) for forcibly sliding the body (B) on the tilt frame (T); a sensor device (S) for detecting the slide position of the body (B) relative to the tilt frame (T); a remote control device (R) capable of commanding the execution and temporary suspension of operation modes of the longitudinal drive device (D) and the lift device (L) involved in the loading and unloading processes of the other vehicle (V'); and a control device (C) capable of controlling switching of operation of the longitudinal drive device (D) and the lift device (L) based on outputs of the remote control device (R) and the sensor device (S),
the longitudinal drive device (D) has a rotating shaft (23f) that rotates in conjunction with the chain (26), and the sensor device (S) includes at least a rotation amount sensor (RS) that can detect the amount of rotation of the rotating shaft (23f);
The rotation amount sensor (RS) includes a sensor gear (71) having a plurality of dog teeth (7a, 7b, 7c, 7a', 7b', 7c') arranged at intervals in the circumferential direction on its outer periphery and rotating in conjunction with the rotation shaft (23f), and a proximity sensor (70) capable of detecting the dog teeth (7a, 7b, 7c, 7a', 7b', 7c'),
The plurality of dog teeth (7a, 7b, 7c, 7a', 7b', 7c') are set to have tooth shapes and pitches such that an output pattern of the proximity sensor (70) that detects them is periodically repeated with the rotation of the sensor gear (71) and is different between when the sensor gear (71) is rotating in the forward direction and when it is rotating in the reverse direction;
The vehicle transporter is characterized in that the control device (C) is capable of calculating the amount of rotation based on the output pattern of the proximity sensor (70) and determining the direction of rotation of the rotating shaft (23f). A vehicle transporter as described in claim 1, characterized in that the multiple dog teeth (7a, 7b, 7c) with different tooth widths are arranged on the outer periphery of the sensor gear (71) in different arrangement patterns during forward and reverse rotation of the sensor gear (71). The vehicle transporter according to claim 1 or 2, characterized in that the control device (C) has means for calculating and storing the direction and amount of displacement based on the output pattern when the body (B) shifts without operation of the remote control device (R) while the body (B) is temporarily stopped during the loading process or the unloading process, and is capable of determining, based on this storage, whether or not to return the body (B) to its initial position when the temporary stop is released, and, if it is determined that the body (B) should be returned, is capable of controlling the longitudinal drive device (D) so that the body (B) returns to its initial position.