JPH026779A - Doppler sensor fitting device in vehicle for work - Google Patents

Abstract

PURPOSE:To prevent the deterioration of the accuracy of a detection value by forming as one body a front grille and a horn antenna of a Doppler sensor and providing an opening part of the horn antenna in front of the front grille. CONSTITUTION:An opening part 3a is pierced in a suitable position in front of a front grille 8 of a work use vehicle 7, and the front grille 8 and a horn antenna 3 are formed as one body so that said part becomes a horn antenna opening part of a Doppler sensor 14. This antenna 3 is tapered toward the rear, and to its rear end part, a Doppler sensor module 4 is fixed. In this state, a microwave which has been transmitted from this module 4 is allowed to have directivity by the antenna 3 and radiated from the opening part of the antenna 3. In this case, the horn antenna opening part is provided in front of the front grille 8, and positioned in sufficient height. Accordingly, since a waterproof and dustproof cover is not installed in the horn antenna opening part, there is no loss of a microwave and the Doppler sensor 14 can work with high performance.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a Doppler sensor mounting device for a working vehicle, and more particularly to a Doppler sensor mounting device for a working vehicle with improved speed detection accuracy.

[Prior Art] This type of conventional Doppler sensor mounting device will be explained with reference to FIG. 3 of the attached drawings. In the figure, (1) is a Doppler sensor unit. The Doppler sensor unit (1)
A horn antenna (3) tapered toward the rear is inserted into a metal sensor case (2) with an open front, and the horn antenna (3) is connected to the front end (2a) of the sensor case (2). The opening (3a) is glued. A Doppler sensor module (4) is fixed to the rear of this horn antenna (3).
) is formed so that the microwaves emitted from the microwave are directed and radiated forward. Then, the microwave reflected by the object reaches the opening (3a) of the horn antenna (3), is reflected on the inner wall surface (3b) and is focused, and reaches the receiving section of the Doppler sensor module (4). You can reach it and get speed information. This Doppler sensor unit (1) is attached to the lower part of the vehicle body via the mounting stay (5), but at this time, there is no possibility that foreign matter such as dirt may enter the opening (3a) of the horn antenna (3). In order to prevent this from entering, a cover (6) made of resin such as acrylic was attached to the opening (3a).

[Problems to be Solved by the Invention] As mentioned above, conventionally, the Doppler sensor unit is attached to the vehicle body via the mounting stay. The relative angle of the Doppler sensor unit was distorted, causing a decrease in the accuracy of detected values. In addition, since a strong resin molded cover such as acrylic is attached to the horn antenna opening to prevent dirt and sand from entering, the resin molded cover weakens the microwaves during transmission and reception. It acts on Therefore, it was necessary to make the microwave output of the Doppler sensor module sufficiently high. Therefore, a technical problem arises that must be solved in order to make the detected value of the Doppler sensor highly accurate and to reduce the loss of microwaves, and the present invention aims to solve this problem.

[Means for Solving the Problems] The present invention has been proposed to achieve the above object, and includes providing an opening in the front grill of a work vehicle,
A work vehicle characterized in that a horn antenna of a Doppler sensor unit for ground speed detection is fitted into the opening and formed integrally, and a Doppler sensor module is attached to the rear end of the horn antenna. The purpose of the present invention is to provide a Doppler sensor mounting device that can be used.

[Function] The present invention has an opening at an appropriate position on the front side of the front grill of a work vehicle, and the front grill and the horn antenna are integrally formed so that the opening becomes the horn antenna opening of the Doppler sensor. are doing. The horn antenna tapers toward the rear, and the Doppler sensor module is fixed to the rear end thereof, so the mounting angle of the Doppler sensor module is constant, and there is almost no error in the mounting angle depending on each vehicle body. . The microwaves emitted from the Doppler sensor module are given directivity by the horn antenna and are radiated from the opening of the horn antenna.

At this time, since the horn antenna opening is provided on the front surface of the front grille, it is located at a height sufficient to prevent entry of earth and sand. Therefore, since a waterproof and dustproof cover such as an acrylic plate is not attached to the horn antenna opening, there is no microwave loss and the Doppler sensor can operate with good performance.

[Embodiment] Hereinafter, an embodiment of the present invention will be described in detail with reference to FIGS. 1 and 2 of the attached drawings. For convenience of explanation, conventionally known techniques will also be explained at the same time. Further, the same reference numerals are used for parts having the same configuration as those used in the conventional example. In FIG. 1, (7) is a work vehicle. A front grill (8) is attached to the front of the work vehicle (η), and cutout holes Qo (1o) are provided on both left and right sides of the front grill (8) to expose headlights (9) (9). It has been drilled. An opening (3a) for the horn antenna (3) is drilled in the middle of the cutout hole Qo)Qo), but the position of this opening should not be particularly limited. Then, the opening (3a
A horn antenna (3) is provided rearwardly projecting from ), and the horn antenna (3) is formed in a tapered shape so as to become thinner toward the rear. In this embodiment, the front grill (8) and the horn antenna (3) are integrally formed by resin molding, but metal or other materials may also be used.

Here, as shown in Fig. 2, the horn antenna (3) is formed with a downwardly facing surface and faces toward the front lower part of the vehicle body, and a Doppler sensor module (3), which is a microwave transmitting and receiving section, is attached to the rear end. 4) Attachment part O so that it can be fixed
D is provided. The angle of the mounting portion 00 determines the microwave radiation angle of the Doppler sensor module (4).
8), the mounting angle error is extremely small and can be ignored.

In addition, since the Doppler sensor module (4) is fixed to the mounting portion O0 by interposing a thin resin plate for waterproofing,
There is no risk that the Doppler sensor module (4) will be submerged in water or that dirt or the like will enter. This waterproof thin plate 021 can be integrally molded with the front grill (8) and the horn antenna (3), in which case the waterproof performance is further improved. Then, a microwave reflecting surface 03) is formed by pasting a metal plate on the inner wall surface of the horn antenna (3) or by metal plating or the like to ensure the performance as an antenna.

Then, the work vehicle (7) equipped with the Doppler sensor (■) consisting of the horn antenna (3) and the Doppler sensor module (4) is driven, and the Doppler sensor (■) is installed.
When detecting the ground speed by
) and is given directivity, and is radiated toward the lower front from the horn antenna opening (3a) above the front grille (8). At this time, the opening (3a) is open and there is no shielding material such as an acrylic plate that would interfere with the microwaves, so the microwaves reach the object with little loss. When the microwave reflected by the object in the direction of the Doppler sensor ω is incident through the opening (3a) of the horn antenna (3), it is reflected and focused on the reflective surface 03) of the inner wall, and the microwave is The light passes through the thin plate 0 and reaches the receiving section of the Doppler sensor module (4).

Here, the difference between the received microwave frequency and the transmitted frequency is calculated, and the ground speed of the work vehicle (7) is detected.

[Effects of the Invention] In the present invention, as described in detail in the above embodiment, the front grill and the horn antenna of the Doppler sensor are integrally formed, and the opening of the horn antenna is provided in the front surface of the front grill. In addition, since the mounting part of the Doppler sensor module is provided at the rear end of the horn antenna, the mounting angle of the Doppler sensor module can be set to the specified value without the need for special adjustment, and the detected value Prevent the accuracy from decreasing. Furthermore, since the Doppler sensor is mounted inside the front grill and placed at a higher position than in the conventional example, there is no risk of dirt or the like entering, so there is no need to provide a dustproof resin plate at the opening of the horn antenna. Therefore, the resin waterproof plate provided at the joint between the Doppler sensor module and the horn antenna can be made thinner, and the microwave transmittance is improved, resulting in good value-reading performance. Furthermore, since the horn antenna and the front grill are integrally molded, the number of parts is reduced, and costs are also reduced.
This invention can exhibit various effects such as simplifying the assembly process.

Therefore, this invention can be modified in various ways without departing from the spirit of the invention, and it goes without saying that this invention extends to such modifications.

[Brief explanation of the drawing]

1 and 2 show one embodiment of the present invention, FIG. 1 is a front view of a working vehicle, FIG. 2 is a partially cutaway side view of the working vehicle, and FIG. 3 is a main part of a conventional example. FIG. (3)...Horn antenna (4)...Dotsupura sensor module (8)
...Front grill 03) ...Reflective surface

Claims (1)

[Claims] An opening is provided in the front grill of a work vehicle, a horn antenna of a Doppler sensor unit for detecting ground speed is fitted into the opening, and a Doppler sensor module is attached to the rear end of the horn antenna. A Doppler sensor mounting device for a work vehicle, characterized by: