TWI391636B - Knock sensor and method of manufacturing the same - Google Patents

Description

Knock sensor and manufacturing method thereof

The invention relates to a knock sensor, and more particularly to a knock sensor and a method of manufacturing the same.

The Chinese Patent Publication No. CN1760654 discloses a "knock sensor and a method of manufacturing the same", which mainly forms a ring groove on the outer peripheral surface of the pipe portion of the base, and a snap ring is sleeved on the pipe portion of the base. After the axial load is applied, the piezoelectric element, the terminal plate, the insulating sheet, the weight, and the like which are previously sleeved on the tube portion of the base are appropriately pressed against each other, and then the stop ring is applied with a diameter. The load is applied such that a certain portion of the snap ring is embedded in the ring groove of the tube portion of the base to complete the fixing of the stop ring to apply a stable preload to the piezoelectric element.

Although the retaining ring of the above patent can effectively solve the problems caused by the use of the nut in the prior art of the above patent, the retaining ring or the nut is used to insulate the piezoelectric element, the terminal plate, and the insulating member by an additional member. The sheet is fixed with components such as counterweights while applying a predetermined load. Therefore, these additional components tend to cause an increase in the overall manufacturing cost, and it is necessary to control the output pressure of the machine and when the pressure reaches a predetermined value, the thrust ring is riveted by the axial force, and the manufacturing process is easy to make the base The tube is deformed, resulting in defective products, and the manufacturing process will of course be more complicated.

SUMMARY OF THE INVENTION A primary object of the present invention is to provide a knock sensor having an inexpensive manufacturing cost and a simple manufacturing process.

To achieve the above object, the knock sensor of the present invention comprises a base, a lower insulating sheet, a lower terminal plate, a piezoelectric element, an upper terminal plate, an upper insulating sheet and a weight. The base has a disc-shaped base portion, a tube portion and a rim, the tube portion extending from the base portion along an axial direction of the base portion, the rim portion extending from the tube portion and surrounding the tube portion The outer insulating sheet, the insulating ring, the lower terminal plate, the piezoelectric element, the upper terminal plate, the upper insulating sheet and the weight are sequentially sleeved on the tube portion of the base, and Stacked sequentially over the base of the base while being forced between the rim of the base and the base of the base.

The knock sensor of the present invention is manufactured by punching the edge of the base with a punch to bend the edge of the base for the lower insulating sheet, the lower terminal plate, The piezoelectric element, the upper terminal plate, the upper insulating sheet and the weight are pressed while applying a predetermined load.

It can be seen from the above that the knock sensor of the present invention omits the extra component, but sets the punching of the riveting machine to directly form the rim at the periphery of the tube portion of the base, which can be bent. The aforementioned components disposed on the tube portion of the base are tightened, effectively achieving the purpose of reducing manufacturing costs and providing a simple manufacturing process.

In order to explain the structure, features, and advantages of the present invention in detail, the following preferred embodiments are illustrated in the accompanying drawings.

Referring to the second figure, a knock sensor (10) according to a first preferred embodiment of the present invention mainly includes a base (20), a lower insulating sheet (30), an insulating ring, and a lower terminal plate (40). a piezoelectric element (50), an upper terminal plate (60), an upper insulating sheet (70), a weight (80), an insulating ring (82), a gasket (84) and a protective layer (86).

The base (20) has a disk-shaped base (22), a tube portion (24) and a ring edge (26). The tube portion (24) extends upward from the top surface of the base portion (22) along the axial direction of the base portion (22) and has a large diameter section (242) and a small diameter section (244); the collar (26) There is a vertical section (262) and a horizontal section (264), the vertical section (262) extends upward from the large diameter section (242) of the tube portion (24), and the horizontal section (264) is defined by the vertical section (262). The end extends horizontally along the radial direction of the tube portion (24) and continuously surrounds the periphery of the small diameter section (244) of the tube portion (24) continuously, as shown in the third figure.

The lower insulating sheet (30) is sleeved on the large diameter section (242) of the tube portion (24) of the base (20) and stacked above the base (22) of the base (20).

The lower terminal plate (40) is sleeved on the large diameter section (242) of the tube portion (24) of the base (20), and is stacked above the lower insulating sheet (30) to pass the lower terminal plate (40) through the lower insulation. The sheet (30) is kept insulated from the base (22) of the base (20).

The piezoelectric element (50) is sleeved on the large diameter section (242) of the tube portion (24) of the base (20) and stacked above the lower terminal plate (40) for sensing transmission by the base (20) The resulting axial vibration is to output a voltage signal.

The upper terminal plate (60) is sleeved on the large diameter section (242) of the tube portion (24) of the base (20), and is stacked above the piezoelectric element (50) while being electrically connected to the lower terminal plate (40). contact.

The upper insulating sheet (70) is sleeved on the large diameter section (242) of the tube portion (24) of the base (20) and stacked above the upper terminal board (60).

The weight (80) is sleeved on the large diameter section (242) of the tube portion (24) of the base (20), and is stacked above the upper insulating sheet (70) to be held by the upper insulating sheet (70). An insulating state between the upper terminal plates (60) for providing a vibration force to the piezoelectric element (50).

The insulating ring (82) is sleeved on the large diameter section (242) of the large diameter section (242) of the base (20), and is located at the large diameter section (242) and the lower terminal board (40) of the tube portion (24), Between the piezoelectric element (50), the upper terminal plate (60) and the weight (80), the base (20) is insulated from the lower terminal plate (40), the piezoelectric element (50), and the upper terminal plate (60). ) and weights (80)

The washer (84) is sleeved on the tube portion (24) of the base (20) and is forced between the horizontal section (264) of the rim (26) of the base (20) and the weight (80). Of course, the gasket (84) can be set without actual needs.

The protective layer (86) is made of synthetic resin and is coated on the periphery of the susceptor (20).

According to the above structure, the knock sensor (10) of the present invention integrally forms a bendable edge (26) on the periphery of the tube portion (24) of the base (20) for lowering the insulating sheet ( 30), the lower terminal plate (40), the piezoelectric element (50), the upper terminal plate (60), the upper insulating sheet (70), the weight (80) and the gasket (84) are pressed, and simultaneously The component is subjected to a predetermined load, and components such as a snap ring or a nut as in the conventional patent are not used. Thereby, since the knock sensor (10) of the present invention omits additional components, the knock sensor (10) of the present invention can provide a simpler manufacturing process and comparison with the conventional patent. Effectively reduce manufacturing costs.

It is worth mentioning that the structure of the knock sensor of the present invention can be varied. As shown in the fourth figure, the knock sensor (90) provided by the second preferred embodiment of the present invention differs mainly in that the rim (96) of the pedestal (92) has four notches (962) (at least A notch can be discontinuously wrapped around the periphery of the tube portion (94) of the base (92), and the element of the tube portion (94) of the base (92) can also be forced through the horizontal portion (964). And apply a predetermined load to the components.

Hereinafter, a method of manufacturing the knock sensor (10) of the present invention will be described with reference to the drawings.

Step a): As shown in Fig. A, a base (20) is provided. The base (20) has a disk-shaped base (22), a tube portion (24) and a ring edge (26). The tube portion (24) extends upward from the top surface of the base portion (22) along the axial direction of the base portion (22) and has a large diameter section (242) and a small diameter section (244); the collar (26) The large diameter section (244) of the tube portion (24) extends upward and continuously surrounds the periphery of the small diameter section (244) of the tube portion (24) continuously.

Step b): As shown in FIG. B, an insulating ring (82), a lower insulating sheet (30), a lower terminal plate (40), a piezoelectric element (50), and an upper terminal plate (60) are sequentially disposed. An insulating sheet (70), a weight (80) and a gasket (84) are sleeved on the large diameter section (242) of the tube portion (24) of the base (20) and sequentially stacked on the base Above the base (22) of the seat (20).

Step c): As shown in the first figure C, the rim (26) of the pedestal (20) is punched using a punch (12), and the rim (26) is bent to form a vertical section (262). The components of step b) are forced with a horizontal segment (264) and horizontal segments (264) while applying a predetermined load, as shown in Figure D.

Step d): coating a protective layer (86) made of synthetic resin on the periphery of the susceptor (20) to complete the manufacture of the knock sensor (10) of the present invention, as shown in the second figure.

Through the above steps, the knock sensor (10) of the present invention only needs to punch the rim (26) of the base (20) through the punch (12) to make the rim (26) of the base (20). By creating a bend, a predetermined load can be applied to the elements of step b). In contrast, in the conventional patent case, the stop ring is sleeved on the tube portion of the base, and the axial load is applied to the stop ring, and then a certain part of the stop ring is embedded in the tube portion of the base. In the ring groove, to complete the fixing of the stop ring. In comparison, the knock sensor (10) of the present invention provides a simpler manufacturing process than the conventional patent, and at the same time effectively reduces the overall manufacturing cost.

It is worth mentioning that the structure of the knock sensor of the present invention can be varied. As shown in the fourth figure, the rim (96) of step a) can have four notches (962) (at least one notch) that do not continuously surround the periphery of the tube portion (94) of the base (92). After the rim (96) is stamped by the punch of step c) to form the horizontal section (964), the component of the tube portion (94) of the pedestal (92) can also be forced through the horizontal section (964). And apply a predetermined load to the components.

The constituent elements of the present invention disclosed in the foregoing embodiments are merely illustrative and are not intended to limit the scope of the present invention. The alternative or variations of other equivalent elements are also covered by the scope of the patent application.

"First Embodiment"

(10). . . Knock sensor

(12). . . shower

(20). . . Pedestal

(twenty two). . . Base

(twenty four). . . Tube department

(242). . . Large diameter section

(244). . . Small diameter section

(26). . . Ring

(262). . . Vertical segment

(264). . . Horizontal section

(30). . . Lower insulation sheet

(40). . . Lower terminal board

(50). . . Piezoelectric element

(60). . . Upper terminal board

(70). . . Upper insulation sheet

(80). . . Counterweight

(82). . . Insulation ring

(84). . . washer

(86). . . The protective layer

"Second embodiment"

(90). . . Knock sensor

(92). . . Pedestal

(94). . . Tube department

(96). . . Ring

(962). . . gap

(964). . . Horizontal section

FIG. 1 is a cross-sectional view showing the susceptor provided by the first preferred embodiment of the present invention;

FIG. 2B is a cross-sectional view showing the state in which the lower insulating sheet, the lower terminal plate, the piezoelectric element, the upper terminal plate, the upper insulating sheet and the weight are sleeved on the tube portion of the base;

The first figure C is a cross-sectional view mainly showing the state in which the punch punches the edge of the base.

The first figure D is a cross-sectional view, mainly showing that the ring edge is bent to form a vertical segment and a horizontal segment.

The second figure is a cross-sectional view of a first preferred embodiment of the present invention.

The third figure is a top view of the protective layer removed according to the first preferred embodiment of the present invention, mainly showing that the rim continuously and continuously surrounds the periphery of the tube portion of the susceptor.

The fourth figure is a top view of the second embodiment of the present invention with the protective layer removed, mainly showing that the rim has four notches and does not continuously surround the periphery of the tube portion of the pedestal.

10. . . Knock sensor

20. . . Pedestal

twenty two. . . Base

twenty four. . . Tube department

242. . . Large diameter section

244. . . Small diameter section

26. . . Ring

262. . . Vertical segment

264. . . Horizontal section

30. . . Lower insulation sheet

40. . . Lower terminal board

50. . . Piezoelectric element

60. . . Upper terminal board

70. . . Upper insulation sheet

80. . . Counterweight

82. . . Insulation ring

84. . . washer

86. . . The protective layer

Claims (10)

A knock sensor includes: a base having a disc-shaped base, a tube portion and a ring edge, the tube portion extending from the base portion along an axial direction of the base portion, the ring edge being the tube a portion extending out and surrounding the periphery of the tube portion; a lower insulating sheet sleeved on the tube portion of the base and stacked above the base portion of the base; and a lower terminal plate sleeved on the tube portion of the base portion And stacked on the lower insulating sheet; a piezoelectric element is sleeved on the tube portion of the base and stacked above the lower terminal plate; an upper terminal plate is sleeved on the tube portion of the base, stacked Above the piezoelectric element, and in electrical contact with the lower terminal plate; an upper insulating sheet is sleeved on the tube portion of the base and stacked above the upper terminal plate; a weight is sleeved on the a tube portion of the base and being urged between the ring edge of the base and the upper insulating sheet; and a gasket sleeved on the tube portion of the base and located at the rim of the base and the weight Between blocks. The knock sensor of claim 1, wherein the tube portion of the base has a large diameter segment and a small diameter segment, the lower insulating sheet, the lower terminal plate, the piezoelectric element, the upper terminal plate, The upper insulating sheet and the weight are sleeved on the large diameter section of the pipe portion; the ring edge has a vertical section and a horizontal section, and the vertical section is formed by the top surface of the large diameter section along the axis of the pipe section Extending vertically, this The horizontal section extends horizontally from the end of the vertical section along the radial direction of the tubular portion and urges the weight. The knock sensor of claim 2, further comprising an insulating ring sleeved on the large diameter section of the tube portion of the base, and located at the large diameter section and the upper terminal plate, the pressure Between the electrical component, the lower terminal plate, and the weight. The knock sensor of claim 1, wherein the rim of the base continuously surrounds the periphery of the tube portion of the base without interruption. The knock sensor of claim 1, wherein the rim of the base has at least one notch and does not continuously surround the periphery of the tube portion of the base. A method of manufacturing a knock sensor according to claim 1, comprising the steps of: a) providing a base having a disk-shaped base, a tube portion and a ring edge, the tube portion being The base extends along the axial direction of the base, the annular edge extends from the tube portion and surrounds the periphery of the tube portion; b) sequentially insulates the insulating sheet, the lower terminal plate, a piezoelectric element, and a The upper terminal plate, an upper insulating sheet and a weight are sleeved on the tube portion of the base and sequentially stacked above the base of the base; c) using a punch to punch the edge of the base, Bending the rim to form a vertical section and a horizontal section, the rim urging the elements of step b) between the rim and the base of the base with the horizontal section, and step b The elements apply a predetermined load; and d) coat a protective layer on the periphery of the pedestal. The manufacturing method according to claim 6, wherein the step b) can be further set A washer is above the weight. The manufacturing method of claim 6, wherein the step b) is capable of arranging an insulating ring on the tube portion of the base, and is located at the tube portion and the upper terminal plate, the piezoelectric element, the lower terminal plate, and the Between the weights. The manufacturing method of claim 6, wherein the rim continuously and continuously surrounds a periphery of the tube portion of the base. The manufacturing method of claim 6, wherein the rim has at least one notch that does not continuously surround the periphery of the tube portion of the susceptor.