Apparatus for measuring tension of belt

• US 5,877,431 A
• Filed: 02/28/1996
• Issued: 03/02/1999
• Est. Priority Date: 04/24/1995
• Status: Expired due to Term

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Hirano, Shigeaki
• Primary Examiner(s): Dombroske, George M.
• Application Number:
  US08/608,058
• Time in Patent Office: 1,098 Days
• Field of Search: 73/862.391, 73/862.41, 73/862.42, 73/862.453
• US Class Current: 73/862.41
• CPC Class Codes: G01H 13/00 Measuring resonant frequency
• CPC Class Codes: G01L 5/042 by measuring vibrational characteristics of the flexible member

Abstract

An apparatus for measuring a tension (T) of a belt in a spanned state includes a vibration detector (1A) for detecting a vibration of the belt, a vibration frequency arithmetic unit (2A) for arithmetically determining a vibration frequency on the basis of the vibration as detected, and a tester (3) equipped with a display device (35). The tester (3) includes an information processor (32) for arithmetically determining a tension (T) of the belt on the basis of the vibration frequency supplied from the vibration frequency arithmetic unit (2A) and information about the belt read out from a storage medium (9), and the display device (35) for displaying the result of the arithmetic operation performed by the information processing means. The storage medium (9) is constituted by an external memory unit capable of being detachably connected to the tester (3). The tension measuring apparatus can profitably be used for detection of a tension (T) of a belt of a belt transmission mechanism employed in a motor vehicle with high accuracy and flexibility.

Claims

1. An apparatus for measuring a tension of a belt in a scanned state, comprising:

vibration detecting means for detecting a vibration of said belt, said vibration being excited by applying vibration exciting energy to said belt;

vibration frequency arithmetic means for arithmetically determining a vibration freauency based on a vibration signal output from said vibration detecting means;

storage means for storing belt information about said belt;

information processing means for performing an arithmetic operation to determine said tension of said belt based on said vibration frequency supplied from said vibration frequency arithmetic means and said belt information read from said storage means; and

display means for displaying a result of said arithmetic operation performed by said information processing means,

wherein said storage means comprises an external memory unit capable of being detachably connected to said information processing means,

wherein said external memory unit stores identification information for identifying a plurality of belts and stores parameters which are used to determine said tension, and

wherein said parameters correspond to said identification information,

wherein one of said vibration frequency arithmetic means and said information processing means is designed to determine a resonance vibration frequency of said belt, and

wherein said information processing means performs said arithmetic operation to determine said tension of said belt in accordance with the following equation;

space="preserve" listing-type="equation">T=k·

m·

l.sup.2 ·

f.sup.2

where k represents a constant,

l represents a span length of said belt,

m represents a unit weight or mass of said belt, and

f represents a resonance vibration frequency of said belt.

2. An apparatus for measuring a tension of a belt in a spanned state, comprising:

vibration detecting means for detecting a vibration of said belt, said vibration being excited by applying vibration exciting energy to said belt;

vibration frequency arithmetic means for arithmetically determining a vibration frequency based on a vibration signal output from said vibration detecting means;

storage means for storing belt information about said belt;

information processing means for performing an arithmetic operation to determine said tension of said belt based on said vibration frequency supplied from said vibration frequency arithmetic means and said belt information read from said storage means; and

display means for displaying a result of said arithmetic operation performed by said information processing means,

wherein said storage means comprises an external memory unit capable of being detachably connected to said information processing means,

wherein said external memory unit comprises a semiconductor memory device, and

wherein said information processing means determines whether or not said vibration of said belt lies within a permissible tolerance based on said belt information stored in said external memory unit.

3. An apparatus for measuring a tension of a belt in a spanned state, comprising:

vibration detecting means for detecting a vibration of said belt, said vibration being excited by applying vibration exciting energy to said belt;

vibration frequency arithmetic means for arithmetically determining a vibration frequency based on a vibration signal output from said vibration detecting means;

storage means for storing belt information about said belt;

information processing means for performing an arithmetic operation to determine said tension of said belt based on said vibration frequency supplied from said vibration frequency arithmetic means and said belt information read from said storage means; and

display means for displaying a result of said arithmetic operation performed by said information processing means,

wherein said belt constitutes at least a part of a power transmission mechanism,

wherein said information processing means is designed to perform a diagnosis of an operation of an apparatus equipped with said power transmission mechanism,

wherein said storage means stores additional diagnosis information to be referenced when said diagnosis is performed,

wherein said apparatus equipped with said power transmission mechanism is a motor vehicle;

wherein said information processing means comprises;

diagnosing means for performing diagnoses of a plurality of different types of motor vehicles in common to detect an abnormality, wherein said diagnoses are performed based on diagnosis information supplied from said storage means; and

interface means for communicating with an electronic control unit of said motor vehicle, and

wherein said display means displays a result of said diagnoses.

4. A belt tension measuring apparatus according to claim 3,

wherein said storage means and at least a second storage means are respectively provided for said plurality of different types of motor vehicles and wherein said storage means and said at least a second storage means are exchangeable with one another depending on said types of said motor vehicles.

5. An apparatus for measuring at least one of tension and vibration characteristics of an object of concern, comprising:

vibration detecting means for generating a vibration detection signal corresponding to at least one of said tension and vibration characteristics of said object;

vibration frequency arithmetic means for generating a vibration frequency signal based on said vibration detection signal; and

information processing/display means for processing said vibration frequency signal,

wherein said vibration detecting means, said vibration frequency arithmetic means, and said information processing/display means are independent units which can be detachably interconnected,

wherein said vibration detecting means comprises one of an acoustic vibration sensor and a direct-contact type vibration sensor,

wherein said vibration frequency arithmetic means comprises;

an input signal comparator for comparing a level of said vibration detection signal supplied from said vibration detecting means with a preset input level and for outputting said vibration detection signal when said level of said vibration detection signal exceeds said preset input level;

signal conditioning means for shaping a waveform of said vibration detection signal and for eliminating noise components from said vibration detection signal;

a first central processing unit for converting said vibration detection signal into a corresponding vibration frequency signal which relates to a vibration frequency of said vibration detection signal; and

a first interface for inputting said vibration frequency signal and outputting a corresponding transmission signal, and

wherein said information processing/display means comprises;

a second interface for receiving said transmission signal and outputting a data signal;

a second central processing unit for processing said data signal to thereby arithmetically determine at least one of said tension and vibration characteristics of said object based on said data signal;

a display device for displaying an image corresponding to at least one of said tension and vibration characteristics determined by said second central processing unit;

a reset circuit for outputting a first reset signal to said second central processing unit to reset said image being displayed on said display device when said reset circuit operates in a first mode and for outputting an automatic reset signal when said reset circuit operates in a second mode; and

a display reset circuit which inputs said vibration detection signal from said input signal comparator when said automatic reset signal is generated by said reset circuit and which outputs a second reset signal reset said image in order to display at least one of said tension and vibration characteristics in accordance with said vibration detection signal supplied from said input signal comparator.

6. An apparatus for measuring a tension of a belt in a spanned state, comprising:

vibration detecting means for detecting a vibration of said belt, said vibration being excited by applying vibration exciting energy to said belt;

vibration frequency arithmetic means for arithmetically determining a vibration frequency based on a vibration detection signal output from said vibration detecting means;

storage means for storing belt information about said belt;

information processing means for performing an arithmetic operation to determine said tension of said belt based on said vibration frequency supplied from said vibration frequency arithmetic means and said belt information read from said storage means; and

display means for displaying a result of said arithmetic operation performed by said information processing means on a display,

wherein said storage means stores identification information for identifying a plurality of belts and stores parameters which are used to determine said tension,

wherein said parameters correspond to said identification information,

wherein one of said vibration frequency arithmetic means and said information processing means is designed to determine a resonance vibration frequency of said belt, and

wherein said information processing means performs said arithmetic operation to determine said tension of said belt in accordance with the following equation;

space="preserve" listing-type="equation">T=k·

m·

l.sup.2 ·

f.sup.2

where k represents a constant,

l represents a span length of said belt,

m represents a unit weight or mass of said belt, and

f represents a resonance vibration frequency of said belt.

13. An apparatus for measuring a tension of a belt as claimed in claim 6, wherein said vibration frequency arithmetic means outputs said vibration detection signal to at least one of said information processing means and said display means, and

wherein at least one of said information processing means and said display means is programmed to update a content of said display in response to said vibration detection signal input from said vibration frequency arithmetic means.

7. An apparatus for measuring a tension of a belt in a spanned state, comprising:

vibration detecting means for detecting a vibration of said belt, said vibration being excited by applying vibration exciting energy to said belt;

vibration frequency arithmetic means for arithmetically determining a vibration frequency based on a vibration signal output from said vibration detecting means;

storage means for storing belt information about said belt,

information processing means for performing an arithmetic operation to determine said tension of said belt based on said vibration frequency supplied from said vibration frequency arithmetic means and said belt information read from said storage means; and

display means for displaying a result of said arithmetic operation performed by said information processing means,

wherein said storage means comprises an external memory unit capable of being detachably connected to said information processing means,

wherein said belt constitutes a part of a power transmission mechanism for a motor vehicle,

wherein said information processing means comprises;

diagnosing means for performing diagnoses of a plurality of different types of motor vehicles in common to detect an abnormality, wherein said diagnoses are performed based on diagnosis information supplied from said storage means; and

interface means for communicating with an electronic control unit of said motor vehicle,

wherein said display means displays a result of said diagnoses, and

wherein said storage means comprises an external memory unit for storing said belt information and said diagnosis information and wherein said external memory unit is removably attached to said diagnosing means.

8. A belt tension measuring apparatus according to claim 7, wherein said storage means and at least a second storage means are respectively provided for said plurality of different types of motor vehicles and wherein said storage means and said at least a second storage means are exchangeable with one another depending on said types of said motor vehicles.

9. A belt tension measuring apparatus according to claim 7,

wherein said information processing means performs an analytical processing operation on said vibration frequency and said display means displays a result of said analytical processing operation on said display device.

10. A belt tension measuring apparatus according to claim 9,

wherein said vibration frequency arithmetic means outputs said vibration detection signal to at least one of said information processing means and said display means, and

wherein at least one of said information processing means and said display means is programmed to update a content of said display in response to said vibration detection signal input from said vibration frequency arithmetic means.

11. A belt tension measuring apparatus according to claim 7,

wherein said vibration frequency arithmetic means transmits said vibration frequency to at least one of said information processing means and said display means via a full duplex serial communication.

12. A belt tension measuring apparatus according to claim 7,

wherein various data transferred among at least two of said information processing means, said display means, and said vibration frequency arithmetic means are transmitted via multiplex communication using a same transmission path by modulating said various data via at least one of a frequency modulation, pulse-width modulation, and a voltage level modulation.