KR100436600B1 - triple action pressure switch apparatus - Google Patents

Abstract

PURPOSE: A pressure switch is provided to prevent damages of pressure switch and allow the pressure switch to operate in a stable manner by increasing a linearity. CONSTITUTION: A pressure switch(100) comprises a cap(102) having a fluid passage; a base combined with the cap; a sealing member(108) fixed between the cap and the base; a first switch(SW1) and a second switch(SW2); and a switch driving unit for operating first and second switches in accordance with the pressure of the fluid. The switch driving unit includes a first pressure sensing disk(110) having a peripheral top surface contacting the bottom surface of the sealing member; a first pivot base(120) having a cavity formed at the center thereof, wherein the first pivot base has an outer surface which directly slides along the inner wall of the base; a second pressure sensing disk(112) having a hole for penetration of the protrusion of the first pivot base; a second pivot base(130) having a hole for penetration of the protrusion of the first pivot base, wherein the second pivot base has a protrusion formed at the bottom surface of the second pivot base, and an outer surface which directly slides along the inner wall of the base; a third pivot base(140) having a top surface contacting the end of the protrusion of the second pivot base, and a space formed by the top surface, inner wall of the protrusion, and the bottom surface of the second pivot base; a third pressure sensing disk(116) having a hole for penetration of the circumferential protrusion of the third pivot base; and a guide pin(190) having a top contacting the bottom surface of the first pressure sensing disk, wherein the guide pin penetrates through the cavity of the first pivot base.

Description

Triple action pressure switch apparatus

The present invention relates to a three-actuated pressure switch, and more particularly, the low pressure sensing disk of the switch driving means is positioned in the middle of three pressure sensing disks, and a new second pivot base and a third pivot base are added to the third switch. The lower surface of the third pivot base by inversion of the pressure sensing disk relates to a tri-operation type pressure switch that can directly open and close the lower switch.

In general, the tri-operation type pressure switch refers to a switch that detects three different pressures and thus controls the on and off of the two switches. It is used to detect various hydraulic pressures, such as brakes and oil pumps, and to operate in multiple stages according to the detected pressure.

An example of such a conventional three-operation pressure switch has been disclosed in Japanese Patent Laid-Open No. 7-114094.

The configuration and operation of the conventional three-operation type pressure switch will be described with reference to FIGS. 1 and 2. 1 is a longitudinal sectional view showing the configuration of a conventional three-operation type pressure switch, and FIG. 2 is a characteristic diagram showing its operating pressure characteristics.

Referring to FIG. 1, a conventional tri-operation type pressure switch includes a housing 1 having a passage for introducing fluid pressure, a switch case 2 combined with the housing 1, a switch 1 and a switch. The diaphragm 22 fixed between the cases 2 by airtightness, the 1st inversion plate 3 whose upper surface abuts on the lower surface of the diaphragm 22, and the periphery of the said 1st inversion plate 3 The first sliding male member 4, which has an annular projection on the lower surface, has a hollow hole in the center, and whose outer circumference slides directly on the inner wall portion of the switch case, and the upper surface is in contact with the annular projection. And a second inverting plate 5 having a hole in the center and a peripheral portion of the second inverting plate 5 as the upper surface, and having the concentric central axis hole in the central portion and the central axis on the lower surface. Has a central projection protruding from the periphery of the hole, The second sliding male member 6 which slides directly into the inner wall portion of the switch case, and the inner circumferential portion are combined with the side surface of the central projection portion, and the third outer circumferential portion is locked to the inner wall end portion of the switch case 2. The second operating rod 24 and the upper end of the inverting plate 7 and the upper end thereof contact the lower surface of the second inverting plate 5 and penetrate the central axis hole of the second sliding male member 6. 1 The first movable member which abuts on the lower surface of the inverting plate 3 and engages with the first operating rod 23 passing through the hollow hole, the hole and the inside of the second operating rod 24 and the lower end of the first operating rod. A first electrical switch portion SW1 composed of a contact point and a fixed contact with which the contact is made; a second movable contact engaged with a lower end of the second operating rod; and a second folding contact with the central protrusion. It consists of the 2nd electrical switch part SW2 comprised of three movable contacts.

Referring to FIG. 2, when the fluid pressure PL + ΔPL is applied to the third snap disk portion 7, the third snap disk portion 7 snaps to the electrical switch portion side, and the second sliding male member 6 Moves toward the electrical switch section, the central projection 25 of the second sliding male member 6 presses the first switch lever 17 of the second electrical switch section SW2, and the second electrical switch section SW2 On.

Further, when the fluid pressure rises to reach PM, the first snap disk portion 3 snaps to the switch portion side, and the first operating rod 23 moves to the first electrical switch portion SW1 side, so that the first electric The switch lever 18 of the switch section SW1 is pressed to open the second electrical switch section SW2.

When the fluid pressure rises to PH again, the second snap disk portion 5 snaps to the electrical switch side, and the second operating rod 24 pushes the second switch lever 16 of the second electrical switch SW2. Lowers and opens the second electrical switch section SW2.

When the fluid pressure drops from PH to PH-ΔPH, the second snap disk portion 5 returns to its original form, and the second electrical switch portion SW2 is closed by the restoring force of the second switch lever 16 ( on).

In addition, when the fluid pressure drops to PM-ΔPM, the first snap disk portion 3 returns to its original form, and the first electric switch portion SW1 is closed by the restoring force of the first switch lever 18 ( on).

In addition, when the fluid pressure drops to PL, the third snap disk portion 7 returns to its original shape, and the second electrical switch portion SW2 is opened by the restoring force of the first switch lever 17. Becomes

Since the conventional three-operation type pressure switch is often used in a place where the temperature change is remarkable such as an air conditioner or an engine room of a car, the first operating rod and the second operating rod have little change in expansion or contraction due to the influence of temperature. Made of Mina Ceramics.

By the way, alumina ceramics are extremely stable thermally, but their toughness is low, so they are easily damaged when impact is applied during the shipment process of the tri-operation type pressure switch or the installation of the tri-operation type pressure switch where necessary. There is a problem.

In other words, the conventional switch driving means has a structure in which the three snap disk units for detecting the medium pressure, the high pressure, and the low pressure are sequentially positioned in the internal space of the tri-operation type pressure switch to open and close the switch. The first operating rod for opening and closing operation and the second operating rod for switching opening and closing operation according to the high pressure is provided separately, the problem that the operating rod is broken by unnecessary interaction between the first operating rod and the second operating rod and the first operating rod In order to open and close the located switch, the length of its own is too long to be easily broken by the external shock was inherent.

In order to solve such a problem, Japanese Laid-Open Patent Publication No. 7-29731 proposes a configuration in which the second operating rod is made of synthetic resin to mitigate the impact applied to the conventional example.

However, when the second operating rod is made of synthetic resin, wear is liable to occur because of poor durability, and the thermal expansion coefficient is greater than that of the alumina ceramic, which may cause undesirable effects in the process of controlling the first switch and the second switch. There is this.

Therefore, there is a need for a tri-operation type pressure switch having a novel structure that can solve the above problems.

The present invention has been made in view of the above necessity, wherein the low pressure sensing disk is located in the middle of the three pressure sensing disks, and a new second pivot base and a third pivot base are added to thereby invert the third pressure sensing disk. It is an object of the present invention to provide an improved three-actuated pressure switch so that the lower surface of the third pivot base can directly open and close the lower switch.

In addition, another object of the present invention is to provide a tri-operation type pressure switch that the guide pin can open and close the upper switch.

Still another object of the present invention is to provide a tri-operation type pressure switch that does not require a second operating rod.

1 is a longitudinal cross-sectional view showing the structure of a conventional three-acting pressure switch.

2 is a view for explaining the operating pressure characteristics of the tri-operation type pressure switch of FIG.

Figure 3 is an exploded perspective view of a three-actuated pressure switch according to an embodiment of the present invention.

4 is a plan view of the tri-operation type pressure switch of FIG.

5 is an A-A longitudinal cross-sectional view showing the structure of the tri-operation type pressure switch of FIG.

6 is a B-B longitudinal sectional view showing the structure of the tri-operation type pressure switch of FIG.

FIG. 7 is a view for explaining an operating pressure characteristic of the tri-operation type pressure switch of FIG. 4; FIG.

Figure 8 is a longitudinal cross-sectional view of a three-acting pressure switch according to another embodiment of the present invention.

FIG. 9 is a view for explaining operating pressure characteristics of the tri-operation type pressure switch of FIG. 8; FIG.

<Description of Symbols for Major Parts of Drawings>

100 ... three-acting pressure switch 102 ... cap

104 ... bass 106 ... O-ring

108. Seal film 110 ... First pressure sensing disk

112 second pressure sensing disk 113 bar hole

114. Upper surface around rod hole 116 ... Third pressure sensing disk

117 ... Circumferential hole 118 ... Top surface around circumferential hole

120 ... first pivot base 122 ... hollow

124 ... protrusions 126 ... flat jaw

130 ... 2nd pivot base 132 ... Sealed

134 ... protrusion 136 ... protrusion inner wall

140 ... the third pivot base 142 ... the circumference

144 shoulder shoulder 150 low terminal

152 ... Low Pressure Operator 154 ... Low Pressure Contact

160 ... high voltage terminal 162 ... high voltage operator

164 ... high voltage contact 170 ... movable terminal

172 ... Movable operator 174 ... Movable contact

180 ... Fixed terminal 182 ... Fixed contact

The present invention for achieving the above object is a cap formed with a passage of compressed fluid; A base in combination with the cap; Airtight means secured between the cap and the base; A three-operation type pressure switch comprising an opening and closing switch and a second switch and switch driving means for changing the opening and closing states of the first and second switches in accordance with the pressure of the fluid. A first pressure sensing disk having an upper surface of the periphery in contact with a lower surface of the means; The peripheral portion of the first pressure-sensitive disk is held on the upper surface, has a hollow at the center, and a flat jaw extending from the hollow and surrounding the outer periphery of the protruding bar is formed on the lower surface, the outer periphery is directly sliding to the inner wall of the base 1 pivot base; A second pressure sensing disk having a rod hole through which an outer circumference of the protruding rod penetrates, and having an upper surface around the rod hole in contact with the flat jaw; The periphery of the second pressure-sensing disk is held on the upper surface, and a hole is formed in the center through which the protruding rod penetrating the rod hole is formed. A protrusion is formed at both ends of the outer circumference, and the outer circumference slides directly on the inner wall of the base. A second pivot base; The end of the protrusion is in contact with the upper surface, and a space is formed on the upper surface, the inner wall of the protrusion and the lower surface of the second pivot base, and the outer circumference of the circumferential protrusion and the circumferential protrusion protruding centered on the lower surface thereof. A shoulder jaw is formed surrounding the third pivot base whose outer periphery is directly slid to the inner wall of the base; A third pressure sensing disk having a circumferential hole through which the circumferential protrusion penetrates, and having an upper surface around the circumferential hole in contact with the shoulder jaw; And a guide pin whose upper end is in contact with a lower surface of the first pressure sensing disk and penetrates the hollow of the first pivot base, wherein an end of the protruding rod and a lower end of the guide pin are formed of the first pin. The opening and closing state of the first switch is changed, and the circumferential protrusion is characterized by changing the opening and closing state of the second switch.

Here, the first switch is located in the space, and folded to the low pressure contact and the low pressure contact (개) to the end of the protruding rod, and includes a high pressure contact to be connected to the lower end of the guide pin It is preferred to be configured.

In addition, the second switch is preferably located below the third pressure sensing disk, and includes a movable contact integrated with the circumferential protrusion and a fixed contact folded with the movable contact. .

Preferably, the airtight means comprises a seal film which makes the passage and the first pressure sensing means airtight, and an O-ring which makes the cap and the base airtight.

In addition, the first pressure sensing disk, the second pressure sensing disk and the third pressure sensing disk are formed in the shape of a plate having a protruding portion on one side thereof, and protrude when a pressure exceeding a predetermined value is applied from the protruding direction. It is preferable to have a hysteresis characteristic that the part is inverted and inverted back to its original state when a pressure applied to the predetermined value is applied.

In addition, the first pressure sensing disk detects the high pressure cutoff pressure PH, PH-ΔPH and performs the inversion operation, and the second pressure sensing disk senses the low pressure cutoff pressure PL, PL + ΔPL and performs the inversion operation. Preferably, the third pressure sensing disk detects the intermediate pressures PM and PM-ΔPM to perform the inversion operation.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Figure 3 is an exploded perspective view of a three-actuated pressure switch according to an embodiment of the present invention, Figure 4 is a plan view of a three-actuated pressure switch, Figure 5 is a AA longitudinal cross-sectional view showing the structure of the three-actuated pressure switch, Fig. 6 is a BB longitudinal cross-sectional view showing the structure of a tri-operation type pressure switch.

3, 4, 5 and 6, the three-actuated pressure switch 100 according to an embodiment of the present invention is the cap 102, the cap 102 is formed a passage of the compressed fluid (流 體) ) In combination with the base 104, the airtight means 106 and 108 fixed between the cap 102 and the base 104, the first switch SW1 and the second switch SW2 that can be opened and closed and the pressure of the fluid. It may be configured to include a switch driving means for changing the opening and closing state of the first switch (SW1) and the second switch (SW2).

The cap 102 and the base 104 are coupled to each other to form a main body of the three-acting pressure switch 100. The first switch SW1, the second switch SW2, and the switch driving means are located in the inner space of the base 104, and the switch driving means is opened and closed according to the pressure applied through the passage. Can be installed to change the state three times.

The airtight means may be composed of a seal film 108 and an O-ring 106. The seal film 108 keeps the passageway of the cap 102 and the first pressure sensing disk 110 in an airtight state so that the flow of fluid does not enter the switch drive means and the base 104 where the switch operates, and The pressure is transmitted to the switch driving means through the first pressure sensing disk (110). The O-ring 106 makes the cap 102 and the base 104 hermetic and may be formed of polyimide resin or the like.

The switch driving means has the greatest feature in the three-acting pressure switch according to the embodiment of the present invention.

In the conventional three-acting pressure switch, the switch driving means is a structure in which three snap disk portions for detecting the medium pressure, the high pressure, and the low pressure are sequentially positioned in the inner space of the three-acting pressure switch to open and close the switch. The first operating rod for the switch opening and closing operation according to the force and the second operating rod for the switch opening and closing operation according to the high pressure is provided separately, the problem that the operating rod is damaged by unnecessary interaction of the first operating rod and the second operating rod and the first In order to open and close the switch located in the lower operating rod has its own problem that can be easily damaged by the external shock because the length is too long.

However, in the tri-operation type pressure switch according to an embodiment of the present invention, the low pressure sensing disk is located in the middle of the three pressure sensing disks, and a new third pivot base is added to the third pressure sensing disk. By adopting a structure in which the lower surface of the third pivot base can directly open and close the lower switch by reversing, the guide pin (the conventional first operating rod) can open and close the upper switch, and the second operating rod becomes unnecessary. .

Therefore, compared with the prior art, the length of the guide pin is shortened by the switch interval, thereby reducing the damage rate due to external impact and increasing the straightness, thereby enabling stable operation. In addition, the problem of operating rod damage due to unnecessary interaction between the conventional first operating rod and the second operating rod is solved.

The switch drive means will be described in detail below.

The switch driving means includes a first pressure sensing disk 110, a first pivot base 120, a second pressure sensing disk 112, a second pivot base 130, a third pivot base 140, and a third pressure. It may be configured to include a sensing disk 116 and the guide pin 190.

The first pressure sensing disk 110, the second pressure sensing disk 112, and the third pressure sensing disk 116 are formed in a plate shape having a protruding portion on one surface thereof, and exceed a predetermined value from the protruding direction. When the pressure is applied, the protruding portion is inverted, and when a pressure that is less than the predetermined value is applied, the protruding portion is inverted again to its original state.

The first pressure sensing disk 110 detects the high pressure cutoff pressure PH and PH-ΔPH and performs the reverse operation. The second pressure sensing disk 112 detects the low pressure cutoff pressure PL and PL + ΔPL to perform the reverse operation. In addition, the third pressure sensing disk 116 detects the intermediate pressure PM and PM-ΔPM to perform an inversion operation.

The upper surface of the peripheral portion of the first pressure sensing disk 110 is in contact with the lower surface of the airtight means 108, and the outer circumference of the peripheral portion is locked to the upper surface of the first pivot base 120. The first pressure sensing disk 110 detects the high pressure cutoff pressure PH and PH-ΔPH to perform the reverse operation.

The first pivot base 120 has an outer circumferential wall formed at an upper surface thereof, has a hollow 122 at a center thereof, and surrounds an outer circumference of the protruding rod 124 and the protruding rod 124 extending from the hollow 122 at a lower surface thereof. The flat jaw 126 is formed, the outer periphery is directly slid to the inner wall of the base 104. The outer circumferential wall of the upper surface engages the periphery of the first pressure sensing disk 110. The first pivot base 120 transmits the pressure of the fluid via the first pressure sensing disk 110 to the second pressure sensing disk 112 through the flat jaw 126 and at the same time the second pressure sensing disk 112. When inverted) is moved downward by the displacement due to the inversion to transfer the pressure to the low pressure operator 152 of the first switch (SW1) via the end of the protruding rod 124.

The second pressure sensing disk 112 has a rod hole 113 through which the outer periphery of the protruding rod 124 penetrates, and the upper surface 114 around the rod hole is positioned to be in contact with the flat jaw 126. The outer circumference of the peripheral portion is locked to the upper surface of the second pivot base 130. The second pressure sensing disk 112 is positioned in the middle of the three pressure sensing disks 110, 112, and 116 to sense the pressure, and detects the low pressure cutoff pressures PL and PL + ΔPL to perform the reverse operation.

The second pivot base 130 has an outer circumferential wall formed on the upper surface thereof, and a bar hole 132 through which the protruding rod 124 penetrates the rod hole 113 is formed at the center thereof, and protrudes from both ends of the outer circumference thereof. 134 is formed and the outer periphery slides directly on the inner wall of the base 104. The outer circumferential wall of the upper surface engages the periphery of the second pressure sensing disk 112.

The third pivot base 140 has an upper end of the protrusion 134 abuts the upper surface, and the outer circumference of the circumferential protrusion 142 and the circumferential protrusion 142 protruding axially on the lower surface of the third pivot base 140. Surrounding shoulder jaw 144 is formed, the outer periphery is directly slid to the inner wall of the base (104). The upper surface is in contact with an end of the protrusion 134, and the upper surface, the inner wall 136 of the protrusion and the lower surface of the second pivot base 130 forms a space in which the first switch SW1 can be installed. do.

The third pivot base 140 receives the pressure of the fluid passing through the first pressure sensing disk 110 and the first pivot base 120 and the second pivot base 130 through the shoulder jaw 144. When the third pressure sensing disk 116 is inverted while being transferred to the sensing disk 116, the movable operator 172 of the second switch SW2 is moved downward by the displacement due to the inversion, and the circumferential protrusion 142 is provided. To deliver pressure.

The third pressure sensing disk 116 has a circumferential hole 117 through which the circumferential protrusion 142 penetrates in the center thereof, and an upper surface 118 around the circumferential hole is in contact with the shoulder jaw 144, and the outer circumference of the peripheral portion Is directly engaged to the disc male portion 105 formed on the inner wall of the base 104. The third pressure sensing disk 116 detects the intermediate pressure PM and PM-ΔPM to perform an inversion operation.

The guide pin 190 has an upper end in contact with a lower surface of the first pressure sensing disk 110 and penetrates the hollow 122 of the first pivot base 120. The guide pin 190 transmits the reversal force of the first pressure sensing disk 110 to the high pressure operator 162 of the first switch SW1 through the lower end portion.

The first switch SW1 is positioned in a space formed by the second pivot base 130 and is coupled to the front end of the low pressure operator 152 and the low pressure operator 152 driven by the end of the protruding rod 124. The high pressure contact 154 coupled to the front end of the high pressure operator 162 and the high pressure operator 162 driven by the lower end of the low pressure contact 154, the guide pin 190, and folded to the low pressure contact 154 ( 164).

The low pressure operator 152 and the high pressure operator 162 may be composed of a leaf spring having a constant elasticity. The low pressure operator 152 has a pin hole 153 through which the guide pin 190 penetrates, and a protruding bar contact portion 155 is formed around the pin hole 153. The low pressure operator 152 is preferably positioned in parallel with the high pressure operator 162 on the high pressure operator 162 so that the low pressure contact 154 and the high pressure contact 164 face each other.

The first switch SW1 is coupled to the low pressure operator 152 and the high pressure operator 162 to fix the low pressure operator 152 and the high pressure operator 162 to the base 104 in the base 104 and the high voltage terminal ( 160) may be further included. The low voltage terminal 150 and the high voltage terminal 160 may be connected to an electric circuit (not shown) outside the three-operation type pressure switch 100.

The second switch SW2 is positioned below the third pressure sensing disk 116 and is coupled to the front end of the movable operator 172 and the movable operator 172 which are driven by the circumferential protrusion 142. And a fixed contact 182 folded to the movable contact 174. The movable operator 172 is located above the fixed contact 182, and the movable contact 174 and the fixed contact 182 may be installed to face each other.

The second switch SW2 may further include a movable terminal 170 and a fixed terminal 180 for fixing the movable operator 172 and the fixed contact 182 to the inside of the base 104. The movable terminal 170 and the fixed terminal 180 may be connected to an electric circuit (not shown) outside the three-operation type pressure switch 100.

Next, operations of the first pressure sensing disk 110, the second pressure sensing disk 112, and the third pressure sensing disk 116 constituting the switch driving means will be described.

The first pressure sensing disk 110 has a shape in which the protruding portion is upward when the pressure of the fluid is below PH, but when the pressure above the PH is applied to the upper surface, the protruding portion is inverted in the downward direction. Is converted. Displacement due to reversal of the first pressure sensing disk 110 presses the guide pin 190 downward, and the lower end of the guide pin 190 presses the high pressure operator 162 of the first switch SW1 to the high pressure contact 164. ) Is separated from the low pressure contact 154, so that the first switch SW1 is electrically opened.

The second pressure sensing disk 112 has a shape in which the protruding portion is directed upward when the pressure of the fluid is PL + ΔPL or less, but when the pressure of PL + ΔPL or more is applied to the upper surface, the protruding portion is directed downward. Converted to inverted form. The displacement due to the inversion of the second pressure disk 112 causes the first pivot base 120 to slide downward, and thus the end of the protruding rod 124 presses the low pressure operator 152 of the first switch SW1. The low pressure contact 154 is brought into contact with the high pressure contact 164 such that the first switch SW1 is electrically closed.

Once the fluid pressure has reached a high pressure and then again goes down to a low PL pressure, the second pressure sensing disk 112 is reversed back to its original form, pushing the first pivot base 120 upwards. As a result, the protrusion bar 124 loses the pressure applied to the low pressure operator 152 of the first switch SW1, and the first switch SW1 is opened again.

The third pressure sensing disk 116 has a form in which the protruding portion is upward when the pressure of the fluid is lower than PM, but when the pressure of PM or higher is applied to the upper surface, the protruding portion is reversed when the pressure is higher than the PM. Is converted. The displacement due to the inverting action of the third pressure sensing disk 116 slides the third pivot base 140 downward, so that the circumferential protrusion 142 presses the movable operator 172 of the second switch SW2. The movable contact 174 is in contact with the fixed contact 182, so that the second switch SW2 is in an electrically closed state.

When the pressure of the fluid is lowered to PM-ΔPM, the third pressure sensing disk 116 is inverted back from the inverted form to the original form and pushes the third pivot base 140 upward. As a result, the circumferential protrusion 142 loses the force holding the movable operator 172 of the second switch SW2, and the second switch SW2 is opened.

The operation of the tri-operation type pressure switch having the configuration as described above will be described with reference to FIG. It is assumed that the pressure of the fluid applied to the switch driving means of the three-actuated switch according to an embodiment of the present invention gradually increases to reach the set high pressure PH and then gradually decreases to fall below the set low pressure PL. .

First, when the pressure PL + ΔPL of the fluid is applied to the first pressure sensing disk 110, the upper surface 114 of the second pressure sensing disk 112 is formed through the flat jaw 126 of the first pivot base 120. The load acts. Due to this load, the second pressure sensing disk 112 is reversed downward, the first pivot base 120 slides downward, and the protruding rod 124 of the first pivot base 120 is the first switch SW1. The low pressure operator 152 is pressed to bring the low pressure contact 154 into contact with the high pressure contact 164 to make the first switch SW1 closed.

At this time, the guide pin 190 is located in the hollow 122 of the first pivot base 120 does not move downward by the movement of the first pivot base 120.

In addition, when the pressure of the fluid rises to reach the pressure PM, the third pivot is via the first pressure sensing disk 110, the first pivot base 120, the second pivot base 130, and the third pivot base 140. The load acts on the upper surface 118 of the third pressure sensing disk 116 through the shoulder jaw 144 of the base 140. By this load, the third pressure sensing disk 116 is inverted downward, the third pivot base 140 slides downward, and the circumferential protrusion 142 of the third pivot base 140 has a second switch SW2. Press the movable operator 172, the movable contact 174 is brought into contact with the fixed contact 182, the second switch (SW2) is turned on (on).

When the pressure of the fluid rises again and rises to the pressure PH, the first pressure sensing disk 110 is inverted, and the reverse force is transmitted to the guide pin 190 which is in contact with the lower center of the first pressure sensing disk 110. Thus, the guide pin 190 is moved downward along the hollow 122 of the first pivot base 120. The lower end of the moved guide pin 190 is pressed by the high pressure operator 162 of the first switch SW1 so that the high pressure contact 164 is separated from the low pressure contact 154 so that the first switch SW1 is electrically open (off). )

When the pressure of the fluid is lowered from PH to PH-ΔPH, the first pressure sensing disk 110 is inverted again to its original form, and the force transmitted to the guide pin 190 is reduced, and the first switch ( The guide pin 190 is moved upward by the elastic force of the high pressure operator 162 of SW1. Thus, the high pressure contact 164 is in contact with the low pressure contact 154, so that the first switch SW1 is electrically closed.

In addition, when the pressure of the fluid decreases to PM-ΔPM, the third pressure sensing disk 116 is inverted again to its original form and pushes up the third pivot base 140 upward. As a result, the circumferential protrusion 142 loses the force holding the movable operator 172 of the second switch SW2, and the movable contact 174 is fixed by the elastic force of the movable operator 172 of the second switch SW2. The second switch SW2 is in an open state by being separated from the contact 182.

In addition, when the pressure of the fluid is lowered again to PL, the second pressure sensing disk 112 is inverted again to its original form and pushes the first pivot base 120 upward. As a result, the protrusion bar 124 loses the force of pressing the low pressure operator 152 of the first switch SW1, and the low pressure contact 154 has a high pressure due to the elastic force of the low pressure operator 152 of the first switch SW1. The first switch SW1 is in an open state by being separated from the contact 164.

As described above, it is possible to tri-operate the tri-operation type pressure switch by using the hysteretic characteristics of the pressure sensing disk of the switch drive means and the elastic force of the operator of the switch.

8 is a longitudinal cross-sectional view of a tri-operation type pressure switch according to another exemplary embodiment of the present invention, and FIG. 9 is a diagram illustrating an operating pressure characteristic of the tri-operation type pressure switch of FIG. 8. Referring to the drawings, in the second switch SW2, the movable operator 172 is positioned below the fixed contact point 182, and the movable contact 174 and the fixed contact point 182 are installed in contact with each other, and the fluid If the pressure exceeds PM, the second switch is in an open state. When the fluid pressure is lowered to PM-ΔPM, the second switch SW2 is in a closed state. Other configurations and operations are the same as described with reference to FIGS. 3, 4, 5, and 6.

As described above, the tri-operation type pressure switch comprises: a first pressure sensing disk having a switch driving means in which an upper surface of a peripheral portion is in contact with a lower surface of an airtight means; The peripheral portion of the first pressure sensing disk is held on the upper surface, has a hollow at the center thereof, and a flat jaw extending from the hollow and surrounding the outer circumference of the protrusion bar is formed on the lower surface, and the outer circumference is directly slid to the inner wall of the base. Pivot base; A second pressure sensing disk having a rod hole through which an outer circumference of the protruding rod penetrates at a center thereof, and having an upper surface surrounding the rod hole on a flat jaw; The periphery of the second pressure-sensing disk is held on the upper surface, and a hole is formed in the center through which the protruding rod penetrating the rod hole is formed. A protrusion is formed at both ends of the outer circumference, and the outer circumference slides directly on the inner wall of the base. A second pivot base; The end of the protrusion is in contact with the upper surface, and a space is formed on the upper surface, the inner wall of the protrusion and the lower surface of the second pivot base, and the outer circumference of the circumferential protrusion and the circumferential protrusion protruding centered on the lower surface thereof. A shoulder jaw is formed surrounding the third pivot base whose outer periphery is directly slid to the inner wall of the base; A third pressure sensing disk having a circumferential hole through which the circumferential protrusion penetrates, and having an upper surface surrounding the circumferential hole on the shoulder jaw; The three-actuated pressure switch of the present invention comprising: a guide pin whose upper end is in contact with a lower surface of the first pressure sensing disk and penetrates the hollow of the first pivot base. do.

First, the guide pin can open and close the upper switch, and accordingly, the length of the guide pin is shorter by the switch interval than in the prior art, so that the damage rate due to external impact is reduced and the straightness is increased so that it can operate stably. do.

Second, the low pressure sensing disk is located in the middle of the three pressure sensing disks, and a new second pivot base and a third pivot base are added so that the lower surface of the third pivot base is directly inverted by the inversion of the third pressure sensing disk. By adopting a structure capable of opening and closing the lower switch, the second operating rod becomes unnecessary, thereby solving the problem of operating rod damage caused by the interaction between the conventional first operating rod and the second operating rod.

It is to be understood that the invention is not limited to that described above and illustrated in the drawings and that many more modifications and variations are possible within the scope of the following claims.

Claims (6)

A cap in which a passage of compressed fluid is formed; A base in combination with the cap; Airtight means secured between the cap and the base; A tri-operation type pressure switch comprising a first switch and a second switch which can be opened and closed and a switch driving means for changing an open / close state of the first switch and the second switch according to the pressure of the fluid, The switch drive means A first pressure sensing disk having an upper surface of a periphery adjacent to a lower surface of the hermetic means; A peripheral portion of the first pressure sensing disk is latched on the upper surface, has a hollow at the center, and a flat jaw extending from the hollow and surrounding the outer circumference of the protrusion is formed on the lower surface, and the outer circumference is formed on the inner wall of the base. A first pivot base sliding directly; A second pressure sensing disk having a rod hole through which an outer circumference of the protruding rod penetrates, and having an upper surface around the rod hole in contact with the flat jaw; The periphery of the second pressure-sensing disk is held on the upper surface, and a hole is formed in the center through which the protruding rod penetrating the rod hole is formed. A protrusion is formed at both ends of the outer circumference, and the outer circumference slides directly on the inner wall of the base. A second pivot base; The end of the protrusion is in contact with the upper surface, and a space is formed on the upper surface, the inner wall of the protrusion and the lower surface of the second pivot base, and the outer circumference of the circumferential protrusion and the circumferential protrusion protruding centered on the lower surface thereof. A shoulder jaw is formed surrounding the third pivot base whose outer periphery is directly slid to the inner wall of the base; A third pressure sensing disk having a circumferential hole through which the circumferential protrusion penetrates, and having an upper surface around the circumferential hole in contact with the shoulder jaw; And And a guide pin having an upper end contacting a lower surface of the first pressure sensing disk and penetrating the hollow of the first pivot base. An end portion of the protruding rod and a lower end of the guide pin change the opening and closing state of the first switch, and the circumferential protrusion changes the opening and closing state of the second switch. The method of claim 1, The first switch is located in the space, and is configured to include a high pressure contact to be folded to the low pressure contact and the low pressure contact (開闔) to the end of the protruding rod, and to the lower end of the guide pin Three-acting pressure switch, characterized in that. The method of claim 1, The second switch is positioned below the third pressure sensing disk, and comprises a movable contact integrated with the circumferential protrusion and a fixed contact folded with the movable contact. Operated pressure switch. The method of claim 1, And said airtight means comprises a seal film which makes said passage and said first pressure sensing means airtight, and an O-ring which makes said cap and base airtight. The method of claim 1, The first pressure sensing disk, the second pressure sensing disk and the third pressure sensing disk are formed in the shape of a plate having a protruding portion on one side thereof, and protruding when a pressure exceeding a predetermined value is applied from the protruding direction. Is inverted and has a hysteresis characteristic which is inverted back to its original state when a pressure applied to the predetermined value is applied thereto. The method of claim 1, The first pressure sensing disk detects the high pressure cutoff pressure PH and PH-ΔPH and performs the inversion operation. The second pressure sensing disk senses the low pressure cutoff pressures PL and PL + ΔPL and performs the inversion operation. The three-pressure sensing disk is a three-acting pressure switch, characterized in that the reversal operation by sensing the intermediate pressure PM, PM- △ PM.