JPH0329692Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a swivel base rotation angle detection device for a working vehicle, in which a rotary encoder is interlocked and connected to the rotating shaft of a swivel base drive reduction gear.

As shown in FIG. 10, the conventional swivel table rotation angle detection device for a work vehicle has a rotary shaft 15 at the end 15a of the swivel table drive reduction gear 14 and a rotated shaft 16a of the rotary encoder 16. the corresponding ends of the bellows coupling 27 are connected in a non-rotating state via screws 28, 28;
Alternatively, as shown in FIG. 1, the crank pin 29
two crank arms 29A, 29A via a
The crank arms 29A, 29A of the crank 29, which are rotationally interlocked, are connected to the corresponding rotating shaft ends 15a and rotated shafts 16a by screws 3, respectively.
The rotary encoder 16 is operatively connected to the rotating shaft 15 by being connected in a non-rotating state via the pins 0 and 30.

However, both of the conventional devices described above have the disadvantage that, because the bellows coupling and crank are screwed together to both shafts, reliability is low due to poor tightening of the screws. In addition, when screwing the bellows coupling and crank together to both shafts, as shown in the diagram,
Through front-cut machining, it is necessary to make the end of the rotating shaft a small diameter that is not much different from the diameter of the rotary encoder's small-diameter rotated shaft. Because it is impossible
Machining to reduce the diameter of the end of the rotating shaft must be performed before heat treatment of the rotating shaft, and as a result,
Due to the heat treatment of the rotating shaft, distortion and deformation of the small diameter rotating shaft end is inevitable, and the detection accuracy is low even though the rotation angle of the swivel table is detected via the rotating shaft of the swivel table drive reduction gear. There are some drawbacks. Especially,
In conventional devices using the former bellows coupling, the bellows coupling itself is expensive, which not only increases costs, but also requires that the bellows coupling be screwed to both shafts after the rotary encoder is installed. Therefore, there is a drawback that it is difficult to assemble.

The purpose of the present invention is to eliminate such conventional drawbacks.

In order to achieve the above-mentioned object, the swivel table rotation angle detection device for a working vehicle according to the present invention has the following features: (a) The rotated shaft of the rotary encoder and the central axis of rotation of the rotary shaft are on the same straight line.

(b) The diameter of the rotating shaft is set larger than the diameter of the rotated shaft.

(c) A crank is provided on the rotated shaft of the rotary encoder, a groove extending in the radial direction is formed in the end face of the rotating shaft, and the tip of the crank is inserted into the groove. It is characterized by having the configurations (a) to (c) above.

The effects of this characteristic configuration are as follows.

In other words, the tip of the crank attached to the rotating shaft (crank pin) is directly engaged with the groove on the end face of the rotating shaft so that it rotates integrally with the rotating shaft, thereby interlocking the rotating shaft with the rotating shaft. Therefore, it is recommended to adopt an easy-to-work assembly method in which the crank is attached to the rotating shaft and then the rotary encoder is assembled so that the tip of the crank engages with the end surface of the rotating shaft. In addition, the number of screws required for interlocking the two shafts can be reduced to one. Moreover,
As a means for engaging the tip of the crank with the rotating shaft, as shown in FIG.
A possible method is to engage the tip of a crank 27' attached to the rotated shaft 16a with the formed protrusion 25', and in this case, similar to the conventional device described above, the rotation shaft heat treatment is performed afterwards. There are disadvantages in that the protrusions may be deformed or the machining of the protrusions may be extremely difficult. In contrast, in the present invention, the tip of the crank is engaged with a groove formed on the end surface of the rotating shaft, and the groove formation itself is easier than the cutting process for forming the protrusion, and The grooves themselves are much less likely to be distorted or deformed by subsequent heat treatment of the rotary shaft than the protrusions, making it easier and more accurate to process the rotary shaft, which is required to interlock the rotary shaft with the rotated shaft. I can do it well.

Furthermore, since the central axes of rotation of the rotated shaft and the rotary shaft are on the same straight line, and the diameter of the rotary shaft is larger than the diameter of the rotated shaft, the crank that engages in the groove on the end face of the rotary shaft also It can be made compact by configuring it in a shape that is located within the outer circumferential diameter of the rotating shaft.

Therefore, according to the present invention, assembly workability is improved;
Moreover, the reliability of the interlocking connection between the rotating shaft and the rotated shaft is high, and the rotating shaft can be interlocked with the rotating shaft with high accuracy, and the rotary encoder is interlocked and connected to the rotating shaft of the speed reduction device for driving the turning table. By combining this with the detection of the rotation angle of the swivel base, it has become possible to provide a swivel base rotation angle detection device for a work vehicle that can detect the rotation angle of the swivel base with high accuracy.

Embodiments of the present invention will be described below with reference to FIGS. 1 to 7.

In the swing-type excavation work vehicle shown in FIG. 1, the swing operation structure for the traveling device 4 of the swivel platform 3 provided with the excavation work device 1 and the tower driving section 2 is constructed as shown in FIG. 2. , a potentiometer 6 is attached to the operating lever 5 to detect its operating state,
Based on the information from potentiometer 6,
A first controller 9 is provided to automatically operate an electromagnetic comparison control valve 8 for the swing motor 7 so as to rotate the swing base 3 in a direction commensurate with the operating direction of the lever 5 and at a speed commensurate with the operating amount. At the same time, based on the rotation angle information θ from the rotary encoder 16 for detecting the anti-travel device rotation angle attached to the rotation drive part of the swivel base 3 and the information from the potentiometer 6, the lever operation is determined as a start command. In this state, the swivel base 3 is rotated in a direction corresponding to the operating direction of the lever 5 and in a preset speed change state, and the rotation angle θf artificially set by the setting device 11 is rotated.
A second controller 12 for automatically operating the proportional control valve 8 is installed in the microcomputer M so that the proportional control valve 8 is stopped at A circuit switch 13 for selectively switching the connection to the valve 8 is provided;
It is configured so that an artificial turning operation by the first controller 9 and an automatic turning operation by the second controller 12 can be selectively performed.

The rotation angle detection sensor unit including the rotary encoder 16 is constructed as shown in FIGS. 2 to 4.
As shown in the figure, one rotating shaft 1 in a gear type reduction device 14 for driving a rotating table is linked to a rotating motor 7.
5, a rotary encoder 16 is interlocked and the detected information value from the rotary encoder 16 is used as the second rotation angle information θ for the automatic turning operation.
The rotating member 18 is configured to be input to the controller 12, and detects that one plate-shaped rotating member 18 attached to the rotating shaft 15 passes as the rotating shaft 15 rotates. Two photo interrupter type auxiliary sensors 19A and 19B are provided on the rotation trajectory of the rotating member 18 to detect the rotation angle of the rotating member 18.

As shown in FIGS. 3 to 5, the rotated shaft 16a of the rotary encoder 16 and the rotating shaft 15 are arranged to face each other in the direction of their rotational axes, and the diameter of the rotating shaft 15 is is set larger than the diameter of the rotated shaft 16a.

In order to interlock and connect the rotary encoder 16 to the rotating shaft 15, the crank arm 23a of the crank 23, which is composed of a crank arm 23a and a crank pin 23b, is integrally connected to the rotating shaft 16a of the rotary encoder 16. It is installed in a rotating state via screws 24, and
A groove 25 extends in the radial direction on the end surface of the rotating shaft 15 and engages the tip of the crank 23, that is, the crank pin 23b, so as to be inserted from the direction of the rotating shaft core and rotated integrally with the rotating shaft 15, and,
Both ends are formed so as to face the circumferential surface of the rotating shaft 15, and the rotated shaft 16a is interlocked with the rotating shaft 15 so as to rotate together with the rotating shaft 15 by engagement between the groove 25 and the crank pin 23b.

To attach the rotating member 18 to be detected to the rotating shaft 15, one end side of the rotating member 18 to be detected is bent, and the rotating member 18 to be detected is rotated so that the bent end 18a is inserted into and engaged with the groove 25. Abut against the end face of the shaft 15, and in this state, fix the longitudinal middle part of the rotating member 18 to be detected to the end face with one screw 26, and then connect the screw 26 and the groove 2 of the bent end 18a.
5, it is attached to rotate integrally with the rotating shaft 15. In other words, when using this mounting means, for example, compared to a means for mounting the detected rotating member 18 in contact with the end face of the rotating shaft 15 in an integrally rotating state via two screws, the screws are
The rotating member to be detected 18 can be easily attached without the need for this, and the rotating member to be detected 18 can be easily attached to the rotating shaft 15 by welding. There is no decrease in accuracy.

And those two auxiliary sensors 19A, 1
Rotation angle information value from 9B and rotary encoder 1
6 is compared with the rotation angle information value from 6 to determine whether the difference between them exceeds the setting, and when the difference exceeds the setting, the buzzer type notification device 20 and the second controller 12 in the microcomputer M A trouble determination circuit 22 that automatically activates the swivel table emergency stop circuit 21 connected to the microcomputer M
It can be installed in the system to reliably detect electrical and mechanical troubles such as disconnection of the rotary encoder 16 or poor interlock between the rotary shaft 15 and the rotary encoder 16, and to input false detection information caused by these troubles. It is configured to prevent the swivel base 3 from running out of control and to quickly make the operator aware of such troubles.

The determination processing means in the trouble determination circuit 22 will be explained with reference to FIG.

On the rotation trajectory of the rotating member 18, the rotation phase thereof is
The passage detection signals transmitted from the auxiliary sensors 19A and 19B, which are arranged such that their passage detection positions are at positions 180 degrees apart, are used as start signals for the determination processing cycle, and are sequentially processed as follows.

(B) Rotation angle information θa transmitted from the rotary encoder 16 at the time of the previous judgment processing cycle, that is, at the time of detection of one passage before the current detection of passage of the rotating member 18, and rotation angle information θa transmitted from the rotary encoder 16 at the time of detection of passage of the rotating member 18 this time. The absolute value Δθ of the difference with the rotation angle information θb transmitted from 16 is calculated.

(b) It is determined whether the previous passage detection and the current passage detection were performed by the same auxiliary sensors 19A and 19B.

In other words, by determining whether or not the same auxiliary sensor detects the detection, it is possible to determine whether the swivel base 3
It is determined whether or not the reverse operation is being performed.

(C) When the previous passage detection and the current passage detection are performed by the same auxiliary sensor, the detection information value from the auxiliary sensors 19A and 19B is 0, and the difference in the detection information from the rotary encoder 16 is calculated. It is determined whether the absolute value Δθ (ideally 0) is within the preset maximum allowable error Δθ _nax1 , and if it is larger than the maximum allowable error Δθ _nax1 , a problem will occur. It makes the judgment and causes the notification device 20 and the emergency stop circuit 21 to issue an activation command.

(d) If the previous passage detection and the current passage detection are performed using different auxiliary sensors, the theoretical rotation angle Δθ _A between both auxiliary sensors calculated in advance from the arrangement of both auxiliary sensors 19A and 19B.

Claims (1)

[Claims for Utility Model Registration] A work vehicle in which a rotary encoder 16 is interlocked and connected to a rotating shaft 15 of a speed reduction device 14 for driving a rotating platform, characterized by having the following configurations (a) to (c). A device for detecting the rotation angle of the swivel base of a work vehicle. (a) Rotated shaft 16 of the rotary encoder 16
a and the central axis of rotation of the rotating shaft 15 are on the same straight line. (b) The diameter of the rotating shaft 15 is set larger than the diameter of the rotated shaft 16a. (c) Rotated shaft 16 of the rotary encoder 16
A is provided with a crank 23, a groove 25 extending in the radial direction is formed in the end face of the rotating shaft 15, and the tip of the crank 23 is inserted into the groove 25.