JP2003139578A - Pointer instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a new and fancy velocimeter 1 without giving uncomfortable feeling in viewing it by evenly dividing a scale between the zero graduation 3a and the maximum graduation 3b, and by making a pointer 6 indicate the graduation 3a when the velocity V is between zero and a predetermined value, in a velocimeter 1 as a pointer instrument. SOLUTION: The scale on a dial 2 from the zero graduation 3a to the maximum graduation 3b are evenly divided, and when the velocity V is 5 km/h or less, a step motor 5 is driven by a control device 8 to make the pointer 6 indicate the zero graduation part 3a, that is, 0 km/h. Thereby, while preventing step-out of the step motor 5, this velocimeter 1 excellent in visibility is realized by restraining unnatural motion of the pointer 6 in an extremely low velocity region. By rotating the pointer 6 in the entire region of the scale part 3 by nearly parallelizing it with the velocity V, the driver is surely prevented from sensing discomfort particularly in a low velocity region when viewing the velocimeter 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pointer measuring instrument, and more particularly to a pointer measuring instrument employing a step motor as a drive source, which is suitable for use in vehicles.

[0002]

2. Description of the Related Art In recent years, with the progress of microcomputer control of various systems mounted on a vehicle, even in a pointer instrument for a vehicle, an actuator which is a drive source for rotating the pointer has a conventional cross coil type. The motor has been replaced with a stepper motor more suitable for microcomputer control.

On the other hand, for example, in a speedometer which is a pointer instrument of a vehicle, a vehicle speed sensor which generates a predetermined number of pulses per one rotation of a wheel is provided, and an actuator is driven by a control device based on an output signal thereof to rotate the pointer. It is moved to indicate the physical speed. In this case, in the extremely low speed range, for example, 10 km / h or less, the above-mentioned vehicle speed sensor pulse interval (time from one pulse to the next pulse)
Becomes longer and the drive of the actuator by the above-mentioned control device becomes unstable. For example, when the vehicle decelerates, the pointer suddenly indicates 0 km / h when the speed reaches around 5 km / h. In order to cope with this phenomenon, in the conventional speedometer using the crossed coil type actuator, the intervals between the graduation portions 3 on the graduation plate 2 are partially uneven. That is, in the range of 0 to 20 km / h, the distance between the scale portions 3 is shortened and the speed is about 8
Below km / h, a mechanical stopper is provided to stop with the pointer pointing at 0 km / h.
6 is a front view of a conventional speedometer 100 using a crossed coil actuator. In the conventional speedometer 100, as shown in FIG. 0 scale parts 3a and 1 which are scales for displaying h
The interval with the 10 scale part 3c which is a scale displaying 0 km / h is compressed. On the other hand, the 10 scale portions 3c and the maximum scale portion 3b are evenly allocated.

Further, in the conventional speedometer 100,
When the actual traveling speed is 0 km / h to 8 km / h,
Pointer 6 is set to 0 scale part 3 by a mechanical stopper (not shown).
It is forcibly stopped at position a. Therefore, when the vehicle starts running in the conventional speedometer 100, the speed is 8k.
Until the pointer reaches m / h, the pointer 6 has 0 scale part 3a, that is, 0k.
Instructing m / h. When the speed exceeds 8 km / h, the pointer 6 rotates to indicate the scale corresponding to the speed.

[0005]

However, the uneven spacing of the scales on the dial due to the above-mentioned increase of 0 may give the driver a visual discomfort. That is, although the vehicle accelerates smoothly, it feels like there is a difference between the movement of the pointer 6 and the instructed speed. In addition, when the above-mentioned mechanical zero increase is performed on a speedometer using a step motor as a drive source, if a pointer is brought into contact with a stopper to forcibly stop the shaft of the step motor, a step out ( There is a problem in that the control of the step motor becomes impossible due to the occurrence of a state where the electrical signal for driving the step motor and the rotation angle of the step motor cannot be maintained).

The present invention has been made in view of the above points, and an object thereof is to provide a graduation plate in which graduations are evenly allocated between the 0 graduation and the maximum graduation, and to specify a physical quantity to be instructed. When is within the range of 0 to a predetermined value, the 0 scale is instructed by the pointer so that there is no sense of discomfort during visual recognition.
It is to provide a pointer instrument with a novel appearance.

[0007]

In order to achieve the above object, the present invention employs the following technical means.

In the pointer measuring instrument according to claim 1 of the present invention, the scale is evenly allocated between the 0 scale and the maximum scale on the scale board, and the physical quantity indicated by the pointer measuring instrument is from 0 to a predetermined value. When the value is in the range of values, the control means drives the step motor to cause the pointer to indicate the 0 scale. As a result, a "0 increase" by a drive signal is performed instead of a "0 increase" by a mechanical stopper (not shown) in the conventional speedometer 100 to prevent step-out of the step motor 5, while increasing the physical quantity. In a small area, the pointer movement can be made smooth, and it is possible to realize a novel pointer instrument that does not feel strange when visually recognized.

In this case, if the instructed physical quantity is the vehicle speed or the engine speed as in claim 2 or claim 3, a novel speedometer or tachometer with no discomfort when visually recognized is realized. it can.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION A case in which a pointer instrument according to the present invention is applied to an automobile speedometer will be described below with reference to the drawings.

FIG. 1 is a front view of a speedometer 1 according to an embodiment of the present invention, and FIG. 2 is a sectional view taken along line II-II of FIG. 1 is the left-right direction of the automobile, the right side of FIG. 2 is the front of the automobile, and the left side is the rear of the automobile, that is, the driver side. Also, in FIG.
The vertical direction in FIG. 2 is the vertical direction of the automobile.

The speedometer 1 is arranged in a position in front of the driver's seat of the automobile, which is visible to the driver. The speedometer 1 is provided with a graduation plate 2 for displaying the speed of an automobile, which is a physical quantity to be instructed, so that the driver can visually recognize it.

The graduation plate 2 is made of a transparent or semi-translucent thin plate of polycarbonate or the like, and a plurality of graduation parts 3 and character parts 4 are printed or hot stamped on the surface thereof except for these. Etc. are formed by coloring. Further, the scale unit 3 includes a 0 scale unit 3a displaying 0 km / h and a maximum scale unit 3 displaying 180 km / h.
It is evenly allocated between the areas b and b. That is, the instruction angle per unit speed is set to be the same in the entire scale portion 3. As a result, the driver can read the speed from the instructed position of the pointer 5b without feeling discomfort even in the low speed range where the scale interval is compressed as shown in FIG. 6 in the conventional speedometer 100.

On the back surface of the graduation plate 2, the light emitted from the light emitting diode 10 which is a light source for illuminating the graduation plate 2 is collected and guided to the graduation plate 2 so that the graduation part 3 and the character part 4 are luminescently displayed. The light guide plate 11 for is fixed. The light guide plate 11 is made of a transparent resin such as acrylic resin.

A case 12 is mounted on the back surface of the graduation plate 2, and a printed circuit board 7 forming an electric circuit portion of the speedometer 1 is accommodated in the case 12. The light emitting diode 10 described above is mounted on the printed circuit board 7. Also,
As shown in FIG. 2, a step motor 5 as a drive source for rotating the pointer 6 is attached to the printed board 7, and a control device 8 for driving the step motor 5 is mounted.

The output signal from the speed sensor 9 is input to the control device 8, and the pointer shaft 6 is moved by a predetermined angle corresponding to the output signal.
The step motor 5 is driven so as to rotate a. FIG. 3 shows an electric circuit configuration diagram in the speedometer 1 according to the embodiment of the present invention. As shown in FIG. 3, the control device 8 calculates the traveling speed of the vehicle on the basis of the output signal from the speed sensor 9 fetched through the speed pulse input device 8e, and determines the indicated angle of the pointer 6 corresponding thereto. CPU (Central Processing Uni)
t) 8a, a drive circuit 8d that drives the step motor 5 so that the pointing angle of the pointer 6 determined by the CPU 8a, a constant voltage circuit 8b that converts the voltage of the battery 16 into a predetermined voltage and supplies the voltage to the CPU 8a, a storage device. 8c and the like. Further, when the CPU 8a detects that the ignition switch 15 is turned on, the light emitting diode 10 is detected.
Is lit to make the display panel 2 visible to the driver.

The step motor 5 rotates the pointer shaft 6a by an angle corresponding to the electric signal from the speed sensor 9.
The pointer shaft 6a extends to the driver side through a central hole 2a provided at a substantially central portion of the dial 2, and the pointer 6 is fixed to the tip end of the dial so as to be rotatable along the surface of the dial 2. ing. The pointer 6 indicates the scale portion 3 on the scale plate 2 to display the speed. The pointer shaft 6a may be driven by a shaft (not shown) of the step motor 5 via a speed change mechanism (not shown), or may be directly connected to the shaft (not shown) of the step motor 5. It may be driven.

An annular dial plate 13 is provided on the surface of the dial 2.
A transparent cover 14 is attached through the.

Next, a speedometer 1 according to an embodiment of the present invention.
The speed display step will be described.

FIG. 4 shows a flowchart of the speed display process in the CPU 8a of the speedometer 1 according to the embodiment of the present invention. Hereinafter, the flowchart shown in FIG. 4 will be described.

First, in step S101, the pulse interval (time value) which is the output signal of the speed sensor 9 is calculated. In the speed sensor 9 of this embodiment, four pulses are generated per revolution of the propeller shaft (not shown).
That is, the pulse interval P is long at low speed, and the pulse interval P is short at high speed.

Next, in step S102, the speed V of the vehicle is calculated based on the pulse interval P calculated in step S101. The calculation of the velocity V is performed by referring to the first map data which is a list in which the pulse interval P and the velocity V corresponding to the pulse interval P are entered. In the first map data of the speedometer 1 according to the embodiment of the present invention, the speed V
Are entered at 1/16 km / h intervals. Therefore, the speed V calculated in step S102 is 1 / 16k.
Values are in m / h increments. The first map data is stored in the storage device 8c of the control device 8.

Next, in step S103, the display position of the pointer 6 corresponding to the speed V calculated in step S102, that is, the angle A of the pointer shaft 6a is calculated. The calculation of the angle A is performed by referring to the second map data which is a list in which the speed V and the angle A corresponding to the speed V are entered. Since the speed V is calculated in steps of 1/16 km / h in step S102, even in the second map data,
The speed V is displayed in steps of 1/16 km / h, and the angle A of the pointer shaft 6a corresponding thereto is entered. The second
The map data of is also stored in the storage device 8c of the control device 8.

Here, the relationship between the speed V and the angle A in the second map data will be described.

In the speedometer 1 according to one embodiment of the present invention, 0 km / h which is the 0 scale portion 3a when the angle A of the pointer shaft 6a is 0 ° and the maximum scale when the angle A of the pointer shaft 6a is 270 °. Since 180 km / h, which is the portion 3b, is displayed, 1 km / h is displayed at 1.5 °.

(A) Speed V is from 0 km / h to 5 km / h
Up to.

In this case, the angle A is 0. In other words, when the vehicle speed V is from 0 km / h to 5 km / h,
The step motor 5 is driven so that the angle A of the pointer shaft 6a is 0 °, and the pointer 6 is at 0 km / m which is the 0 scale portion 3a.
pointing to h. As a result, the mechanical motor (not shown) of the conventional speedometer 100 is used instead of the "zero-up", and the step motor 5 is driven so that the pointer 6 points to the zero scale portion 3a. By carrying out a typical "0 increase", while preventing the step motor 5 from getting out of step,
It is possible to realize the speedometer 1 having excellent visibility by suppressing the unnatural movement of the pointer 6 in the extremely low speed range.

(B) Speed V is 5 km / h to 20 km /
For up to h.

In this case, the angle A is 0 ° when the speed V is 5 km / h, and the angle A is 30 ° when the speed V is 20 km / h.
Becomes Further, the angle A corresponding to the speed V on the way is
The linear interpolation is set so that the pointer shaft 6a is rotated by 30 ° and displayed at 15 km / h, which is the change width of the speed V from 5 km / h to 20 km / h. As a result, the interval compression of the scale portion 3 in the low speed range (0 to 20 km / h) of the conventional speedometer 100 is stopped, the entire area of the scale portion 3 is made uniform, and the rotation of the pointer 6 is linear to the speed change of the vehicle. Since it corresponds to, it is possible to realize a speedometer 1 with a novel appearance that does not cause discomfort when visually recognized.

(C) Speed V is 20 km / h to 180 k
Up to m / h.

In this case, the angle A corresponding to the speed V is 1
It is set so as to maintain the relationship such that km / h is displayed at 1.5 °.

Next, in step S104, the drive signal D to be applied to the step motor 5 corresponding to the angle A of the pointer 6 calculated in step S103 is calculated. The drive signal D is calculated by referring to the third map data which is a list in which the angle A and the drive signal D corresponding to the angle A are entered. Then, in step S105, step S
The drive signal D calculated in 104 is output to the drive circuit 8d of the control device 8. The drive circuit 8d drives the step motor 5 based on the drive signal D to rotate the pointer shaft 6a up to a predetermined angle, and the pointer 6 indicates a predetermined speed.

When the vehicle speed V changes due to the driver's accelerator operation or brake operation, the drive signal D is output to the drive circuit 8d so as to rotate the pointer 6 correspondingly. At this time, the drive circuit 8d drives the step motor 5 in an angular velocity or angular acceleration range that does not cause step out of the step motor 5.

The visual recognition state of the speedometer 1 according to the embodiment of the present invention configured as described above will be described.

FIG. 5 is a graph showing the relationship between the vehicle speed V and the indicated speed K indicated by the pointer 6 on the dial 2 in the speedometer 1 according to the embodiment of the present invention.

As shown in FIG. 5, the vehicle speed V is 5 km.
If less than / h, the pointer 60 scale portion 3a, that is, 0 km /
Instructing h. When the vehicle speed V exceeds 5 km / h, the pointer 6 starts to rotate smoothly. At this time, the relationship between the speed V and the instructed speed K is linear, but the speed V is 20 km.
The indicated speed K is slightly smaller than the speed V until it reaches / h. When the speed V exceeds 20 km / h,
The relationship between the speed V and the instruction speed K is linear, and the instruction speed K and the speed V are substantially the same.

On the other hand, as shown in FIG. 1, the compression of the scale in the low speed range in the conventional speedometer 1 is abolished on the scale board 2 and the scale portion 3 is evenly divided from the 0 scale portion 3a to the maximum scale portion 3b. Since the pointer 6 is rotated from the low speed range substantially corresponding to the speed V while shaking, it is possible to surely prevent the driver from feeling uncomfortable especially in the low speed range when the driver visually recognizes the speedometer 1.

In the speedometer 1 according to the embodiment of the present invention described above, the physical quantity indicated by the speedometer 1, that is, the magnitude of the speed is from 0 to a predetermined value, for example, 5k.
When it is within the range of m / h, the stepping motor 5 which is the drive source is driven by the control device 8 which is the control means to cause the pointer 6 to indicate the 0 scale portion 3a. As a result, by performing “0 increase” by the drive signal instead of “0 increase” by the mechanical stopper (not shown) in the conventional speedometer 100, it is possible to prevent the step motor 5 from being out of step, and It is possible to realize the speedometer 1 having excellent visibility by suppressing the unnatural movement of the pointer 6 in the low speed range.

Further, the speedometer 1 according to the embodiment of the present invention.
In the conventional speedometer 1, the graduation portion 3 is evenly allocated from the 0 graduation portion 3a to the maximum graduation portion 3b without compressing the intervals of the graduation portions 3 in the low speed range in the conventional speedometer 1, and the pointer 6 is set from the low speed region. The rotation was made to approximately correspond to the speed V. As a result, when the driver visually recognizes the speedometer 1, it is possible to reliably prevent the driver from feeling discomfort, especially in the low speed range.

In the speedometer 1 according to the embodiment of the present invention described above, the indication value of the maximum scale portion 3b is set to 180 km / h, but it may be changed if necessary.

Further, in the speedometer 1 according to the embodiment of the present invention described above, the scale portion 1 has a velocity of 1 km / km.
Although h is displayed at 1.5 °, it may be changed if necessary.

Further, in the above-described embodiment of the present invention, the pointer instrument is applied to the speedometer 1, but it may be applied to other indicator instruments, for example, a tachometer which indicates the engine speed as a physical quantity. Good.

[Brief description of drawings]

FIG. 1 is a front view of a speedometer 1 according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 shows a speedometer 1 according to an embodiment of the present invention,
It is an electric circuit block diagram.

FIG. 4 is a CPU 8 of the speedometer 1 according to the embodiment of the present invention.
It is a flow chart of a speed display process in a.

FIG. 5 shows a speedometer 1 according to an embodiment of the present invention,
6 is a graph showing a relationship between a vehicle speed V and an instruction speed K indicated by a pointer 6 on the dial 2.

FIG. 6 is a front view of a conventional speedometer 100.

[Explanation of symbols]

1 Speedometer (pointer instrument) 2 scale plate 3 scale section 3a 0 scale 3b maximum scale 4 character part 5 step motor 6 guidelines 6a Pointer shaft 7 printed circuit board 8 control device 8a CPU 8b constant voltage circuit 8c storage device 8d drive circuit 8e Velocity pulse input device 9 Speed sensor 100 Conventional speedometer A angle D drive signal K instruction speed P pulse interval V speed (physical quantity)

Claims (3)

[Claims] 1. A scale plate, a step motor arranged on the back side of the scale plate, a pointer that rotates along the surface of the scale plate according to rotation of the step motor, and a physical quantity detection signal. In a pointer instrument provided with a control means for correspondingly driving the step motor, a scale is evenly allocated between 0 scale and a maximum scale on the scale board, and the magnitude of the physical quantity is from 0 to a predetermined value. When in the range
A pointer instrument, wherein the control unit drives the step motor to cause the pointer to indicate the 0 scale. 2. The pointer instrument according to claim 1, wherein the physical quantity is a vehicle speed. 3. The pointer instrument according to claim 1, wherein the physical quantity is an engine speed.