JPH08105739A - Detection apparatus of swiveling position of construction machine - Google Patents

Abstract

PURPOSE: To obtain a detection apparatus by which the swiveling position of an upper-part swiveling body with reference to a lower-part running body can be detected easily in a construction machine comprising the upper-part swiveling body. CONSTITUTION: In a construction machine, an upper-part swivel body 5 is mounted on, and installed at, a lower-part running body 4 via a rotary joint. In the construction machine, a hollow cylindrical cam 1 which surrounds a rotary joint rotor 2 is fixed to, and installed at, the lower-part running body 4, and the upper stage and the lower stage of the cam 1 are formed in such a way that their outside diameters are different in every two regions out of a frontward region, a rearward region, a leftward region and a rightward region. In addition, in the lower stage of the cam 1, only one region out of two regions in which the outside diameter of the upper stage is large is formed in such a way that its outside diameter is small, and only one region out of two regions in which the outside diameter of the upper stage is small is formed in such a way that its outside diameter is large. Then, two sensors 7, 8 are fixed to, and installed at, the upper-part swiveling body 5, they are moved along the upper-stage side face and the lower-stage side face of the cam 1, and they are turned on and off according to whether the outside diameter of the cam 1 is large or small. Thereby, the swiveling position of the upper-part swiveling body 5 is detected by the switching state of the two position sensors 7, 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a turning position detecting device for a construction machine such as a hydraulic excavator, and more particularly to a turning position detecting device for determining a relative position between an upper revolving structure and a lower traveling structure. is there.

[0002]

2. Description of the Related Art Conventionally, in this type of construction machine, an upper revolving structure is formed so as to be rotatable with respect to a lower traveling structure. Therefore, when the operator sits in the cockpit of the upper swing structure and is working while swinging the upper swing structure, the relative position of the upper swing structure with respect to the lower traveling structure may be lost, and There is a risk of accidental misjudgment of direction.

Therefore, in order to prevent such an erroneous operation of traveling, a potentiometer is incorporated in the rotary joint, and the position of the traveling motor is displayed in the cockpit by detecting the rotation angle of the upper revolving body, so that the operator can perform the upper revolving movement. Means for recognizing the relative position of the body with respect to the lower traveling body are known.

[0004]

Since the conventional turning position detecting device incorporates the potentiometer in the rotary joint as described above, not only the cost is greatly increased but also the assembling work is not easy. There is also a problem with the durability of the device.

Therefore, there is a technical problem to be solved in order to reduce the cost by making the turning position detecting device simpler and to improve the durability of the device. The purpose is to solve.

[0006]

DISCLOSURE OF THE INVENTION The present invention has been proposed in order to achieve the above object, and in a construction machine in which an upper swing body is mounted on a lower traveling body via a rotary joint, the upper swing body is rotated. A hollow cylindrical cam that surrounds the rotary joint rotor is fixed to the lower traveling body along the outer periphery of the rotary joint rotor that is fixed to the body and rotates, and the upper and lower stages of the cam are forward facing. Region, rearward region, leftward region, rightward region are formed to have different outer diameters every two regions, and the lower stage of the cam is one of the two regions of the upper stage having a large outer diameter. Is formed to have a small outer diameter, and the outer diameter of only one of the two regions having a small outer diameter in the upper stage is formed to be large, and further, two position sensors are provided on the upper swing body near the rotary joint rotor. While fixed, the two position sensors are moved along the upper side surface and the lower side surface of the cam, respectively, and the two position sensors are turned ON and 0FF to each other, thereby turning the turning position of the upper swing body. A turning position detecting device for a construction machine for judging is provided.

[0007]

When the upper revolving structure is swung, the two position sensors move along the upper and lower side surfaces of the hollow cylindrical cam, respectively, and the two position sensors are moved depending on the outer diameter of the cam. Each turns ON and 0FF.

Thus, the outer diameters of the upper and lower stages of the cam are combined into four types of large and large, large and small, small and large, and small and small for each of the four regions. Two position sensors are ON and ON, ON and 0FF, 0FF and ON, 0FF and 0F for every four areas.
Form four switching states of F.

Thus, it is possible to determine whether the upper swing body is located in the frontward area, the rearward area, the leftward area or the rightward area based on the switching state.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to FIGS. In FIG. 1, reference numeral 1 denotes a hollow cylindrical cam, which is fixed to a lower traveling body 4 via a rotary joint housing 3 while surrounding the rotary joint rotor 2. As shown in FIG. 3 and FIG. 4, the outer diameter of the cam 1 is small in both the upper and lower stages in the forward region a, large in both the upper and lower stages in the rearward region b, and large in the upper region in the leftward region c. The lower tier is small, and the upper tier is small and the lower tier is large in the right area d.

Further, the rotary joint rotor 2
Two limit switches 7 and 8 are fixedly mounted on the upper revolving superstructure 5 in the vicinity through brackets 6 as position sensors, and the terminals of the limit switch 7 engage with the upper side surface of the cam 1 and The terminal is engaged with the lower side surface of the cam 1. When the limit switches 7 and 8 are in contact with the area of the cam 1 having a large outer diameter, the terminals are pressed and turned on, while when they are in contact with the small area, the pressing of the terminals is released. Is set to 0FF.

Thus, when the turning position of the upper swing body 5 with respect to the lower traveling body 4 is in the forward region a, as shown in FIG. 5, the two limit switches 7 and 8 are both outside diameters of the cam 1. Is in contact with a small area, so both are 0FF
It has become. When the upper revolving structure 5 rotates counterclockwise with respect to the lower traveling structure 4, the terminals of the limit switches 7 and 8 slide along the upper side surface and the lower side surface of the cam 1, respectively. When the body 5 enters the leftward region c, the limit switch 8 is still in contact with the lower outer diameter region of the cam 1 and remains 0FF as shown in FIG. The terminal is pressed and switches to ON by climbing onto the area with a large outer diameter.

Further, when the upper revolving structure 5 rotates counterclockwise and enters the rearward region b, the limit switch 8 also rides on the region where the lower outer diameter of the cam 1 is large, as shown in FIG. The two limit switches 7 and 8 are both
It is turned on. Further, when the upper revolving structure 5 rotates counterclockwise and enters the rightward region d, the limit switch 7 enters the region where the outer diameter of the upper stage of the cam 1 is small as shown in FIG. By doing so, it is switched to 0FF, while the limit switch 8 remains ON in the region where the lower outer diameter of the cam 1 is large.

Thus, depending on the mutual switching state of the two limit switches 7 and 8, the upper swing body 5 is placed in any of the forward region a, the backward region b, the leftward region c or the rightward region d. You can determine if you are located. The present invention can be variously modified without departing from the spirit of the present invention, and it goes without saying that the present invention extends to the modified one.

[0015]

As described in detail in the above one embodiment, the present invention is constructed so that the turning position of the upper turning body can be easily detected by the hollow cylindrical cam and the two position sensors. Therefore, as compared with the conventional means for incorporating a potentiometer, not only a great cost reduction can be realized, but also the assembling work becomes extremely easy.

Further, since the invention uses a mechanical cam mechanism, it is an invention which exhibits various effects such as excellent durability and easy maintenance and repair.

[Brief description of drawings]

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

FIG. 2 is a partially sectional front view of FIG.

FIG. 3 is an end view of the cam in FIG. 2 taken along the line AA.

4 is an end view of the cam in FIG. 2 taken along the line BB.

FIG. 5A is a partially cutaway side view showing the engagement state of the cam and the two limit switches when the upper swing body is in the frontward region, as seen from the leftward region side. (B) A plan view showing the postures of the lower traveling body and the upper swing body at that time.

FIG. 6A is a partially cutaway side view showing the engagement state of the cam and the two limit switches when the upper swing body is in the leftward region, as seen from the rearward region side. (B) A plan view showing the postures of the lower traveling body and the upper swing body at that time.

FIG. 7A is a partially cutaway side view showing the engagement state of the cam and the two limit switches when the upper swing body is in the rearward region, as seen from the rightward region side. (B) A plan view showing the postures of the lower traveling body and the upper swing body at that time.

FIG. 8A is a partially cutaway side view showing the engagement state of the cam and the two limit switches when the upper swing body is in the rightward region, as seen from the frontward region side. (B) A plan view showing the postures of the lower traveling body and the upper swing body at that time.

[Explanation of symbols]

 1 Hollow cylindrical cam 2 Rotary joint rotor 4 Lower traveling body 5 Upper revolving body 7,8 Limit switch

Claims (1)

[Claims] 1. In a construction machine in which an upper revolving structure is mounted on a lower traveling structure via a rotary joint, the rotary revolving rotor is fixed along the outer periphery of the rotary joint rotor fixedly mounted on the upper revolving structure. A hollow cylindrical cam is fixed to the lower traveling body, and the upper and lower stages of the cam have outer diameters in every two regions of the frontward region, the rearward region, the leftward region, and the rightward region. The lower stage of the cam, which is formed differently, has a small outer diameter only in one of the two regions having a large outer diameter in the upper stage, and has a small outer diameter in one of the two regions in the upper stage having a small outer diameter. The outer diameter of only the region is formed to be large, and further, two position sensors are fixed to the upper revolving structure near the rotary joint rotor, and the two position sensors are provided on the upper side surface and the lower side of the cam, respectively. A turning position detecting device for a construction machine, characterized in that the turning position of an upper-part turning body is determined by moving the two position sensors to be turned on and off by moving the two position sensors along a plane.