Classifications

• • G—PHYSICS
  • G10—MUSICAL INSTRUMENTS; ACOUSTICS
  • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
  • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
  • G10K11/004—Mounting transducers, e.g. provided with mechanical moving or orienting device
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
  • G01H1/00—Measuring characteristics of vibrations in solids by using direct conduction to the detector
  • G01H1/003—Measuring characteristics of vibrations in solids by using direct conduction to the detector of rotating machines
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
  • G01H11/00—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by detecting changes in electric or magnetic properties
  • G01H11/06—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by detecting changes in electric or magnetic properties by electric means
  • G01H11/08—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by detecting changes in electric or magnetic properties by electric means using piezoelectric devices
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
  • G01L23/00—Devices or apparatus for measuring or indicating or recording rapid changes, such as oscillations, in the pressure of steam, gas, or liquid; Indicators for determining work or energy of steam, internal-combustion, or other fluid-pressure engines from the condition of the working fluid
  • G01L23/22—Devices or apparatus for measuring or indicating or recording rapid changes, such as oscillations, in the pressure of steam, gas, or liquid; Indicators for determining work or energy of steam, internal-combustion, or other fluid-pressure engines from the condition of the working fluid for detecting or indicating knocks in internal-combustion engines; Units comprising pressure-sensitive members combined with ignitors for firing internal-combustion engines
  • G01L23/221—Devices or apparatus for measuring or indicating or recording rapid changes, such as oscillations, in the pressure of steam, gas, or liquid; Indicators for determining work or energy of steam, internal-combustion, or other fluid-pressure engines from the condition of the working fluid for detecting or indicating knocks in internal-combustion engines; Units comprising pressure-sensitive members combined with ignitors for firing internal-combustion engines for detecting or indicating knocks in internal combustion engines
  • G01L23/222—Devices or apparatus for measuring or indicating or recording rapid changes, such as oscillations, in the pressure of steam, gas, or liquid; Indicators for determining work or energy of steam, internal-combustion, or other fluid-pressure engines from the condition of the working fluid for detecting or indicating knocks in internal-combustion engines; Units comprising pressure-sensitive members combined with ignitors for firing internal-combustion engines for detecting or indicating knocks in internal combustion engines using piezoelectric devices
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
  • G01P15/00—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
  • G01P15/02—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses
  • G01P15/08—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values
  • G01P15/09—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values by piezoelectric pick-up
  • G01P15/0907—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values by piezoelectric pick-up of the compression mode type
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10N30/00—Piezoelectric or electrostrictive devices
  • H10N30/01—Manufacture or treatment
  • H10N30/02—Forming enclosures or casings
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10N30/00—Piezoelectric or electrostrictive devices
  • H10N30/30—Piezoelectric or electrostrictive devices with mechanical input and electrical output, e.g. functioning as generators or sensors
  • H10N30/302—Sensors

Definitions

• the invention relates to a vibration sensor with a pressure sleeve according to the preamble of the main claim.
• the vibrations to be detected are knocking noises of the internal combustion engine in operation, which are conducted via the pressure pulses to a piezoceramic disk as the actual sensor element with adjacent contact disks and insulating disks that enable the signal to be picked up, and thus generate an evaluable electrical output signal ,
• the spring and a seismic mass take place, for example, with a threaded ring which can be screwed onto a corresponding thread on the pressure sleeve.
• the above-mentioned vibration sensor with a pressure pulse in which the pressure pulse can be attached under pressure to a component causing vibrations and in which a sensor arrangement is held under axial pretension on a support surface between contact disks and insulating disks arranged above it, is advantageously further developed according to the invention, that the entire sensor package is glued or soldered.
• the seismic mass, the sensor element and the contact washers and insulating washers axially on both sides of the sensor element are bonded to one another (and to the support surface?) On the axial boundary surfaces. It is in each case on the side facing the sensor element.
• a conductive adhesive is arranged on the side of the contact washers and the respective insulating washer is formed by a non-conductive adhesive layer.
• the proposed attachment of the sensor package is advantageous in that, for example, the plate spring, the threaded ring and also the insulating washers can be omitted. This enables a lower overall height and a lower weight of the vibration sensor. Also form through the compact attachment of the
• Sensor package relatively lower resonance frequencies of the system, consisting of the sensor package and the fastening screw of the vibration sensor on the component to be detected. Bending vibrations of the cylindrical middle part of the pressure pulses are not transmitted to the piezoceramic of the sensor element, which results in a better frequency response of the detected signal.
• the seismic mass, the sensor element and the contact disks which are axially on both sides of the sensor element are on the axial boundary surfaces to one another, or also to the support surface, either glued or soldered, the contact disks being soldered to the sensor element and glued to the other elements.
• the seismic mass can also be placed under the contact disc facing you
• Elimination of the insulating washer are soldered directly. The same applies to the connection between the contact plate and the contact surface on the pressure sleeve.
• the use of a piezoceramic without electrodes can also be provided.
• the piezoceramic of the sensor arrangement is usually always equipped with electrodes or with a corresponding metallized layer, since it is already polarized by the respective manufacturer.
• a piezoceramic without an electrode it is also advantageously possible to polarize only after the attachment, i.e. by soldering or conductive adhesive, the contact disks follow.
• the seismic mass, the sensor element and the contact disks lying axially on both sides of the sensor element are advantageously soldered to one another at the axial delimitation surfaces, or also on the support surface, one in each case on the axial delimitation surfaces of the sensor element ceramic film or disk is arranged as a contact and insulating disk, which can be soldered on both sides.
• the entire sensor package can be completely soldered during assembly.
• FIG. 1 shows a section through a knock sensor housing as a vibration sensor with a pressure sleeve according to the prior art
• Figure 2 shows a detail section through a soldered or glued sensor package, consisting of contact disks and piezoceramic disk as a sensor element and a seismic mass.
• FIG. 1 shows a knock sensor for an internal combustion engine with an outer plastic housing 1, in which a pressure sleeve 2 is arranged, as a known vibration sensor.
• the pressure sleeve 2 has in the area of its lower end a flange-like edge 3, over which it rests with its lower base surface 20 on the engine block, not shown here, whose vibrations are to be detected.
• the following parts are arranged on the outer circumference 4 of the pressure sleeve 2, starting from a lower contact surface 21 on the flange-like edge 3: an insulating washer 5, a first contact washer 6, a piezoceramic washer 7 as the actual sensor element and, in turn, a second contact washer 6 and a second insulating washer 5.
• a seismic mass 8 is placed on this arrangement, which is printed with an annular spring 9 in the direction of the piezoceramic disk 7.
• the spring 9 is preloaded by a threaded ring 10 which is screwed onto an external thread 11 on the upper part of the pressure sleeve 2.
• Electrical connections 13 for the contact disks 6 and flat plugs 14 are injected into an integrated connection part 12 of the housing 1, which is produced in particular by a plastic injection molding process.
• the tabs 14 are thereby connected to the two contact disks 6, whereby there is an electrical connection to the two sides of the piezoceramic disk 7 via the two contact disks 6 and the electrical voltage which is generated in the axial direction when the piezoceramic disk 7 is subjected to pressure is removable is.
• a fastening screw, not shown here, can be guided through a central recess or a bore 15 in the pressure sleeve 2, with which overall this knock sensor can be fastened directly or indirectly to the engine block of the internal combustion engine.
• the entire torque exerted by the fastening screw described above is transmitted to the pressure sleeve 2 via the lower surface 20, ie no force acts on the piezoceramic disk 7 as the sensor element due to the fastening.
• a prestressing force acts here due to the pressure of the spring 9.
• the prestressing force is selected such that axial forces which can be tolerated on the piezoceramic disk 7 just without permanent deterioration of the electrical signal are effective, and these also result from thermal expansions and inevitable compression of the pressure sleeve 2 during assembly is largely independent.
• the impulses exerted by the seismic mass 8 in proportion to the vibrations of the internal combustion engine are converted in the piezoceramic disk 7 m charge impulses, which can be evaluated on a corresponding device.
• FIG. 2 shows a more detailed illustration of the sensor package according to the invention, consisting of contact disks or equivalent components 6.1 and 6.2 and the piezoceramic disk 7 and the seismic mass 8.
• a conductive adhesive layer 20 and 26 can be arranged on the side of the contact disks 6.1, 6.2 facing the piezoceramic disk 7.
• the insulating washers are formed here by a non-conductive adhesive layer 22 towards the support surface 21 and by a non-conductive adhesive layer 23 towards the seismic mass 8.
• a ceramic film or disk can be arranged on the axial boundary surfaces of the piezoceramic disk 7 as a contact and insulating disk 6.1 and 6.2, these being provided on both sides with a solder layer.

Landscapes

• Physics & Mathematics (AREA)
• Engineering & Computer Science (AREA)
• General Physics & Mathematics (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Acoustics & Sound (AREA)
• Multimedia (AREA)
• Manufacturing & Machinery (AREA)
• Measuring Fluid Pressure (AREA)
• Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)

Priority Applications (3)

Applications Claiming Priority (2)

Publications (2)

Family

ID=7932649

Family Applications (1)

Country Status (5)

Cited By (1)

Families Citing this family (2)

Citations (3)

• 1999
  • 1999-12-15 DE DE19960324A patent/DE19960324A1/de not_active Withdrawn
• 2000
  • 2000-11-23 KR KR1020027007436A patent/KR20020065561A/ko not_active Application Discontinuation
  • 2000-11-23 JP JP2001545802A patent/JP2003517593A/ja active Pending
  • 2000-11-23 WO PCT/DE2000/004144 patent/WO2001044756A2/de not_active Application Discontinuation
  • 2000-11-23 EP EP00989801A patent/EP1240478A2/de not_active Ceased

Patent Citations (3)

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