JP3396279B2 - Speed alarm for forklift - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speed alarm device for a forklift for monitoring the traveling speed and notifying a driver of overspeed to promote safe driving.

[0002]

2. Description of the Related Art As a speed alarm device for a forklift truck, there has been known a device which measures a running speed from the rotation of a roller driven by contact with a tire and issues an alarm when the speed is equal to or higher than a set speed. ing.

[0003]

The roller type sensor used in the conventional speed alarm device for a forklift has a large size and weight, and since it is a contact type sensor, the mounting bracket has a large size. In addition, it was inevitably large in strength and could not be made compact and lightweight. Further, a device using such a roller type sensor has a problem in reliability because it has a decrease in detection accuracy due to abrasion or the like and has a mechanical error.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a speed alarm device for a forklift truck, which is small in size and light in weight, and which uses a sensor free from wear and mechanical error. And

[0005]

A speed alarm device for a forklift according to the present invention uses a hub mounting bolt or a wheel mounting bolt on the inside of a wheel as a detection plate directly or a detection plate separately manufactured on the inside of the wheel. A non-contact sensor attached to a bolt or the like to detect the rotation of the tire, and means for calculating the traveling speed based on the detection signal of the sensor and outputting a signal for an alarm when the traveling speed is equal to or higher than the set speed. It is configured with the device body provided,
The sensor is a mounting bracket consisting of upper and lower brackets.
Knuckle on the wheel with upper and lower brackets
Attach by sandwiching the rate and tightening with bolts
The structure

It is advantageous to use a proximity switch as the sensor. As the detection plate for the sensor, for example, a hub mounting bolt inside a tire such as a rear wheel can be used. Then, in this case, the sensor can be mounted by, for example, a knuckle plate of a rear wheel, which is a free wheel, sandwiched between upper and lower brackets and attached by bolt fastening, or the bracket can be directly attached to the knuckle plate by welding.

Further, it is preferable that the main body of the apparatus is provided with means for making it possible to adjust the set speed from the outside, and also it is provided with means for making it possible to adjust the operation constant from the outside according to the axle height. It is good to say

[0008]

According to the present invention, the rotation of the tire is detected by a non-contact type sensor such as a proximity sensor, the time for the tire to make one rotation is measured based on the detection signal, and the running speed is calculated from the tire diameter. It Then, the calculated traveling speed is compared with the set speed, and if it is equal to or higher than the set speed, an alarm signal is output and an alarm is issued by an alarm lamp of the main body of the apparatus or an external alarm buzzer or light.

Since the sensor is a non-contact type sensor such as a proximity sensor, it is small and lightweight, has no wear and mechanical error, and the mounting structure can be simplified. For example, a knuckle plate for the rear wheel can be used. It can be easily attached by sandwiching it with the upper and lower brackets and tightening it with bolts.

Further, since the set speed can be adjusted from the outside and the arithmetic constant can be adjusted from the outside according to the axle height, it can be applied to a wide variety of vehicle types and freely adjusted after mounting. Is possible.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an overall view showing a forklift speed alarm device according to an embodiment of the present invention in a mounted state. In FIG. 1, reference numeral 1 is a proximity switch, and 2 is a main body of a device having an arithmetic circuit built therein.

The proximity switch 1 includes upper and lower brackets 3A,
It is fixed to the upper bracket 3A of the proximity switch mounting bracket 3 made of 3B. The proximity switch 1 is located inside the rear wheel 4 on the center line 6 of rotation of the plurality of hub mounting bolts 5 arranged on the same circumference at equal pitches, and the gaps between the hub mounting bolts 5 and the heads are approximately equal. Is set to be 5 mm,
The upper and lower brackets 3A and 3B sandwich the knuckle plate 7 of the rear wheel 4 and are fastened to each other by bolts 8 to be fixedly attached. The head of each hub mounting bolt 5 constitutes a detection plate (dock) facing the proximity switch. FIG. 2 is a detailed view of the structure of the mounting portion of the proximity switch 1. Common parts with FIG. 1 are designated by the same reference numerals. Reference numeral 9 in FIG. 2 is a pilot lamp for confirming the operation.

When the rear wheel 4 rotates, the head of each hub mounting bolt 5 rotationally moves on the rotational center line 6, and the proximity switch 1 detects the rotational movement. Then, the detection signal is used as a rotation signal of the rear tire, and the proximity switch cable 10
Is sent to the apparatus main body 2 via.

The apparatus main body 2 is attached, for example, under a forklift panel at a position where it is not exposed to rain. And
An arithmetic circuit built in the device main body 2 calculates the time required for the rear wheel tire to make one rotation based on the detection signal of the proximity switch 1, and also the rear wheel axle height (height from the ground to the center of the rear wheel). The running speed is calculated by calculating the tire diameter of the rear wheel from the set value of. Then, when the traveling speed is equal to or higher than the set speed, an overspeed determination signal is output. The device main body 2 is equipped with an alarm lamp 11 using a light emitting diode as a standard equipment, and the alarm lamp 11 lights up when the speed is exceeded.

The speed setting dial 12 is provided on the main body of the apparatus.
And an axle height dial 13 are provided. The speed setting dial 12 can be set to a speed over judgment speed of 5 km / h by simply turning the digital switch with a flathead screwdriver.
It can be set arbitrarily within the range of 20 km / h, and the adjustment hole is always covered with a blind cap (grommet). Further, the axle height dial 13 is also set by adjusting the axle height by turning it with a flathead screwdriver, and the adjustment hole is always covered with a blind cap (grommet).

Further, the main body 2 of the apparatus is equipped with a large-capacity external contact, and a rotating lamp, an alarm buzzer, an external lamp, etc. can be attached thereto. In FIG. 1, 14 indicates an alarm buzzer. Further, reference numeral 15 is a plug connector.
The alarm buzzer 14 has a lead wire (white) 16 connected to the plug-in connector 15, and the other lead wire (black) 17 is body-grounded (in the case of a gasoline vehicle or a diesel vehicle) (in the case of a battery vehicle, a negative contact point). Connected). In addition, when the key switch 18 is turned on, the speed alarm device is also turned on so that the key switch 18
And the plug connector 15 are connected by a lead wire (red) 19, a snap switch 20 and a fuse 21 are connected in the middle of the lead wire (red) 19, and a lead wire (green) 22 bypassing the fuse 21 is inserted. It is connected to the connector 15. Plug connector 1
5 also has a body grounded lead wire (black)
23 is connected.

The present invention is not limited to the above embodiment, but can be implemented in various other modes. For example,
As the detection plate, wheel mounting bolts can be used in addition to the hub mounting bolts, and a separately manufactured detection plate may be mounted on these bolts. For example, in the case of hub mounting bolts, the number of bolts varies depending on the type of forklift, such as 4, 6, and 8 bolts. When the number of bolts is 10 or more, the bolts are used as detection plates instead of directly detecting them. It is convenient for the management of ROM to attach one plate for the hub to the hub mounting bolt and calculate as one hub bolt. A method of attaching the detection plate to the tire with a strong adhesive or the like is also possible. In addition, the proximity sensor can be attached by welding the bracket directly to the knuckle plate.

[0019]

Since the present invention is constructed as described above and uses a non-contact type sensor, the sensor and its mounting structure can be made compact and lightweight and does not take up space. It is possible to eliminate the mechanical error and provide a highly reliable speed alarm device.

Further, by making it possible to adjust the set speed of the alarm point from the outside and adjust the tire size from the outside, it is possible to adapt to various specifications of the forklift. You can

[Brief description of drawings]

FIG. 1 is an overall view showing a forklift speed alarm device according to an embodiment of the present invention in a mounted state.

FIG. 2 is a detailed view showing a mounting structure of a proximity switch according to an embodiment of the present invention.

[Explanation of symbols]

1 Proximity switch 2 device body 3 Proximity switch mounting bracket 4 rear wheels 5 Hub mounting bolt 7 Knuckle plate 11 alarm lamp 12 Speed setting dial 13 axle height dial

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Claims (4)

(57) [Claims] 1. A non-contact sensor for detecting rotation of a tire by setting a detection plate inside a wheel, and a traveling speed calculated based on a detection signal of the sensor when the traveling speed is equal to or higher than a set speed. A forklift speed alarm device comprising a device body having means for outputting an alarm signal , wherein the sensor is a mounting bracket consisting of upper and lower brackets.
Fixed to the wheel, and the knuckle of the wheel with the upper and lower brackets.
Pin plate and clamp it with bolts
A structure for forklift trucks that has a structure to attach
Ped alarm device . 2. The speed alarm device for a forklift according to claim 1, wherein a proximity switch is used as the sensor. 3. The speed alarm device for a forklift according to claim 1 or 2, wherein the main body of the device includes means for adjusting the set speed from the outside. 4. The speed alarm device for a forklift according to claim 1 or 2, wherein the main body of the device is provided with means for externally adjusting a calculation constant in accordance with the axle height.