JPS63293318A - Friction detecting device for ball joint - Google Patents

Abstract

PURPOSE:To make it possible to grasp the friction condition securely by transmitting a detected friction signal intermittently by radio, and making to judge to be a regular signal when the signals are same in plural rounds as well as maintaining the just prior detected result in a monitor unit until the following signal is obtained. CONSTITUTION:A friction detector 12 consists of a permanent magnet 8, a hole element 9, a battery 10, and an electron circuit 11 including a timer, and detects the friction condition inside a ball joint from the variation of the magnetic flux density perceived. When an abnormal friction of the ball joint 1 is perceived by the detector 12, the same pulse signal is transmitted intermittently from a transmitter 13 by radio in special rounds. Such a signal is received by a receiver 14 through an antenna 18, and delivered to a signal judge block 15. The signal judge block 15 decides to be a regular signal when the signal pulses are same in the specific rounds, and the resultant signal is delivered to a monitor unit 16. The monitor unit 16 maintains the just prior signal until the following signal is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a ball joint used in, for example, an automobile suspension system, and is used to detect wear of a ball joint by intermittently transmitting information on wear inside the ball joint by radio waves. Regarding equipment.

Conventional technology A conventional technology for detecting internal wear of a ball joint and activating an alarm is disclosed in Japanese Patent Application No. 61-140910, in which a predetermined signal is detected based on the output of a wear detector attached to the ball joint. It has been considered to install a transmitter that intermittently outputs radio wave signals and a battery that supplies electrical energy to these transmitters.

By intermittently transmitting the intermediate point detection results by several pulses at predetermined intervals, the battery life can be greatly extended, but the receiver and the signal judgment block connected to it can easily detect false detections. It becomes easier to wake up.

In other words, since cars run freely, there are many opportunities to receive many noise signals, and as a result, the signal judgment block misidentifies irrelevant signals as legitimate signals, and the monitor shows results that are different from the wear status. There are issues that appear.

Means to Solve the Problem In order to increase battery life, the detection results are transmitted intermittently by radio waves, and the monitor device is made to hold the previous detection result until the next signal is obtained.

Further, the signal determining block connected to the receiver is provided with a function of determining that the signal is a regular signal when the signal pulse is the same multiple times.

It is possible to suppress the energy consumption of the elements mounted on the operational ball joint, and to strictly distinguish between information from various radio wave signals that are considered to be disturbances and information on the wear status of the ball joint, which is a regular signal.

Example Embodiments of the present invention will be described below based on the drawings.

FIG. 1 shows a lower ball joint 1 used in a front suspension of an automobile.

This ball joint 1 includes a stud 2, a socket 4,
It includes a load support bearing 5, a wear compensation bearing 6, and a closing plate 7.

The socket 4 has a cylindrical shape and has openings at both ends, one of which is closed by a closing plate 7, and the other opening allows the handle of the stud to protrude swingably.

The closing plate 7 is made of a rigid non-magnetic material such as stainless steel or aluminum alloy. The stud 2 has a spherical head 3 at one end of the handle.

The head 3 of the stud is arranged in the socket 4 with the half on the handle side supported by a load-bearing bearing 5 and the half on the side opposite to the handle supported by a wear compensation bearing 6.

Moreover, the head 3, together with the wear compensation bearing 6, is constantly pressed toward the socket opening by a push-up annular portion made of an elastic material such as rubber that is compressed by the attachment of the closing plate 7.

Therefore, when using the ball joint) head 3 or bearing 5.
, 6 are worn, the wear compensation bearing 6 will move relatively toward the socket opening.

The load support bearing 5 and the wear compensation bearing 6 are appropriately selected from resins with excellent wear characteristics such as nylon, polyethylene, polyacetal, and polyurethane.

A permanent magnet 8, which will be described later, is disposed on the bottom surface of the wear compensation bearing 6 on the side opposite to the spherical seat surface. The magnetic field formed by this permanent magnet extends outside the closing plate 7 made of non-magnetic material.

The closing plate 7 is fixed to the socket opening by deforming the peripheral edge of the socket opening by caulking onto the closing plate 7.

A Hall element 9 serving as a magnetic force sensing device for sensing the magnetic force of the permanent magnet 8 is coupled and fixed to the side surface of the closing plate 70 on the anti-wear compensation bearing side.

On the closing plate 7, a battery 10 and an electronic circuit 11 are placed outside.
is fixed.

In Fig. 2, 12 is a detector, which is composed of the permanent magnet 8 shown in Fig. 1, a Hall element 9, a battery 10, and an electronic circuit 11 including a timer. Detect wear conditions.

13 is a transmitter which receives the output of the detector 12 and outputs a predetermined radio signal from the antenna 17.

A receiver 14 receives the output from the transmitter 13 via an antenna 18.

15 is a signal judgment block. Further, 16 is a monitor device.

Next, wear detection in the ball joint will be explained.

If the ball joint 1 experiences abnormal wear during use, the resilient force of the wear compensation bearing 6 causes the head 3 to move relatively toward the opening of the socket.

Along with this, the permanent magnet 8 also moves away from the Hall element 9,
The sensed magnetic flux density decreases.

As a result, when current is supplied to the transmitter 13 from the batch IJ 10, the detector 12 detects abnormal ball joint wear, and the same pulse signal indicating abnormal wear is transmitted from the transmitter 13, for example, eight times in a row. Ru. .

Note that the signal from the transmitter 13 that conveys the internal wear condition of the ball joint is transmitted intermittently by several pulses, for example, every 12 hours.

The receiver 14 receives this radio wave signal with the antenna 18 and sends it to the signal judgment block 15.

The signal determination block 15 determines that the signal is a regular signal when the signal pulse is the same eight times, and sends the determination result based on the regular signal to the monitor device.

Therefore, if the same signal pulse is detected less than eight times, it is determined to be a noise signal.

In addition, if a regular signal is not sent to the signal judgment block 15 even after 12 hours, the detector 12 or the transmitter 1
3, it is determined that an abnormality has occurred.

The monitor device 16 uses mechanical display or electro-optical effects to visually inform the driver of the wear condition, but in any case, it holds the previous detection result until the next signal is obtained.

That is, the display on the monitor device 16 changes in conjunction with the intermittent cycles of the transmitter 13 that transmits intermittent radio waves, but does not change depending on other noise signals.

Furthermore, with this configuration, energy consumption on the receiving side can also be suppressed.

Effects As described above, according to the present invention, energy consumption of elements mounted on the ball joint can be suppressed, and information from various radio signals considered as disturbances and ball joint wear status, which is a normal signal, can be suppressed. Since the receiver and the signal judgment block connected thereto can be strictly distinguished from each other, false detection will not occur.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a cross-sectional plan view of a ball joint. FIG. 2 is an explanatory diagram of the principle of the wear sensing device. (Explanation of symbols) 1...Ball joint. 12・・・・・
Detector. 13...Transmitter. 14・・・・・
receiver. 15...Signal judgment block. 16...
...Monitor device.

Claims (1)

[Claims] The ball joint 1 is provided with a detector 12 for detecting the state of internal wear and a transmitter 13 that intermittently transmits the detection results by several pulses at predetermined time intervals. A signal judgment block 15 is connected to the signal judgment block 15 which judges the signal to be a regular signal when the times are the same, and a monitor device 16 is connected to the signal judgment block 15 to hold the immediately previous detection result until the next signal is obtained. Joint wear detection device.