JP7430156B2 - pressure switch - Google Patents

Description

The present invention relates to a pressure switch equipped with a pressure-sensitive member that is displaced by pressure fluctuations in a high-pressure chamber separated from a low-pressure chamber.

2. Description of the Related Art Pressure switches equipped with a diaphragm, a bellows, or the like as a pressure-sensitive member have been known. Such pressure switches are of the manual reset type, which switches the conduction state when an abnormal event such as abnormally high pressure in a high pressure chamber occurs, and maintains the conduction state after switching until the operator presses the reset button. (For example, see Patent Document 1). Here, the pressure state in the high pressure chamber at which the conduction state is switched as an abnormal event is appropriately set at the design stage or the manufacturing stage.

Japanese Patent Application Publication No. 2021-061094

The above-mentioned manual reset type pressure switch has a second state in which the movable electrode is in contact with one fixed electrode of the microswitch when a high-pressure cutoff occurs, for a period of time until the operator performs maintenance work. , a positioning means is provided as a member for maintaining. In such a pressure switch, in a reset state in which the reset button is pressed, the positioning means serving as a stopper of the connecting member is pushed in by pressing the reset button, and the stopper is released.

However, since the positioning means is a plate-like member, it is easily bent, so warping and distortion occur due to the reaction force caused by the spring properties of the contact plate, resulting in variations such as errors and fluctuations in the operating value (reset adjustment position). There were cases where this occurred. In addition, since the positioning means is screwed and fixed at one place to the flat plate part of the base body, when the reset button is pressed during the reset operation, it rotates around the screwed part as a fulcrum, causing a shift in the adjusted position. There was a risk that the operating value would fluctuate. Furthermore, the reset adjustment screw does not sit well, and the adjustment position of the positioning means may change due to the inclination of the screw. Therefore, it is necessary to determine the adjustment accuracy in consideration of the distortion of the positioning means, resulting in a problem that the range of adjustment becomes narrow.

Therefore, the present invention focuses on the above-mentioned problems, and its purpose is to improve the strength of the positioning means, suppress fluctuations in the adjustment position of the positioning means, and prevent variations in operating values. The object of the present invention is to provide a manual reset type pressure switch that can improve adjustment accuracy and operate precisely.

In order to solve the above problems, the pressure switch of the present invention includes a pressure-sensitive member that is provided inside a housing, partitions a low-pressure chamber and a high-pressure chamber, and is displaced by pressure fluctuations in the high-pressure chamber; a transmission member that transmits the displacement to a subsequent part by moving in a preset forward/backward direction in response to a displacement; and when the transmission member advances to a first position in the forward/backward direction, the transmission member changes from a first state to a second state. switching means for switching a conduction state from the second state to the first state when the transmission member regresses to a second position on the retraction side from the first position; positioning means for releasably positioning the transmission member in a direction halfway between the first position and the second position; and releasing the positioning of the transmission member by the positioning means, and positioning the transmission member. a reset means for shifting to a free state movable in the advance/retreat direction, and the positioning means positions the transmission member at a position of a belt-shaped plate member and the plate member in the advance/retreat direction. a position adjustment screw for adjusting the position of the plate member, a convex portion extending along the longitudinal direction is provided on the plane portion of the plate member, and a back side of the convex portion conforms to the shape of the convex portion. A folded portion extending along the longitudinal direction is provided at one end in the transverse direction of the plane portion of the plate member, and the recess is provided with a folded portion extending along the longitudinal direction. When the top of the position adjustment screw is engaged and the positioning is released by the reset means, the folded portion comes into contact with the mounting portion of the plate member in the casing.

According to the pressure switch of the present invention, the planar portion of the plate member in the positioning means is provided with a convex portion extending along the longitudinal direction, thereby improving the strength of the positioning means and making it difficult to bend. It is possible to suppress the occurrence of warpage and distortion. In addition, the back side of the convex part of the flat part has a concave part corresponding to the shape of the convex part, and the top of the position adjustment screw is engaged with this concave part, so the seating of the position adjustment screw is improved. Therefore, it is possible to suppress the occurrence of variations such as errors and fluctuations in the operating value (reset adjustment position). Furthermore, since a folded part extending along the longitudinal direction is provided at one end in the lateral direction of the flat part of the plate member, the folded part is disposed when the positioning is canceled by the reset means. The positioning means can be prevented from rotating by coming into contact with the mounting portion of the plate member on the body. Therefore, it is possible to suppress fluctuations in the adjustment position of the positioning means, prevent variations in the operating value, and improve the accuracy of adjustment by the positioning means. Thus, the pressure switch of the present invention allows precise operation.

Here, in the pressure switch of the present invention, it is preferable that the folded portion is formed by bending one end in the lateral direction of the flat portion.

According to this configuration, the strength of the flat part can be further improved, and since the folded part is configured integrally with the flat part, an increase in the number of parts can be avoided.

Further, in the pressure switch of the present invention, the rotary member is rotatably supported around a central axis disposed on one end side, and the other end side is a rotary member movable in the advancing and retracting directions, and A connecting member to which the transmitting member is connected and which rotates in response to displacement of the pressure sensitive member at an intermediate position between the central axis and a connecting point of the transmitting member to move the transmitting member in the advancing and retracting direction. , the positioning means further includes a contact portion extending from the plane portion in the advancing/retreating direction and abutting on a back surface of the other end of the connecting member facing the retreating side in the advancing/retracting direction; The portion has a fixed end at one end and a free end movable in the advance/retreat direction, and the position adjustment screw moves the free end in the advance/retreat direction to adjust the connection member relative to the other end side. It is preferable that the abutting position of the abutting portion is moved back and forth in the advancing and retreating direction.

According to this configuration, the positioning means can reliably position the transmission member at an intermediate position by adjusting the contact position of the positioning means with respect to the other end of the connecting member by moving it forward or backward. It can be carried out. In addition, since strict control of component dimensions is not required, increases in component prices can be suppressed. Furthermore, with the good operability of moving the free end of the plane part, it is possible to reliably position the transmission member at the abutment position, and by extension, at an intermediate position in the position of the transmission member by the positioning means.

According to the present invention, by improving the strength of the positioning means, suppressing fluctuations in the adjustment position of the positioning means, and preventing variations in operating values, it is possible to improve adjustment accuracy and enable precise manual reset. We can provide different types of pressure switches.

FIG. 1 is an external perspective view of a pressure switch according to an embodiment. FIG. 2 is a cross-sectional view schematically showing the internal structure of the pressure switch in FIG. 1 along line V11-V11. FIG. 3 is a perspective view showing a positioning means and a reset means taken out from FIG. 2; FIG. 4 is an enlarged perspective view showing the positioning means in FIG. 3; FIG. 4 is a diagram illustrating the operation of the pressure switch according to the embodiment from the time when the pressure in the high pressure chamber rises to an abnormally high pressure (abnormally high pressure) until the pressure drops thereafter. 6 is a diagram showing the operation of the pressure switch when a reset operation is performed on the reset means following the operation in FIG. 5. FIG. FIG. 5 is a diagram showing a procedure in advance adjustment by the adjusting means in FIG. 4 until the positioning means is moved to a position corresponding to the operating point. 8 is a diagram showing a procedure subsequent to the procedure in FIG. 7 until the transmission member is positioned at the reset adjustment position. FIG.

Hereinafter, one embodiment of the pressure switch according to the present invention will be described in detail with reference to the drawings. The pressure switch according to the present embodiment is used to detect the pressure of a working medium of an air conditioner, a cold/heat generator, an automobile, various control actuators, etc. as a pressure fluid.

As shown in FIGS. 1 and 2, the pressure switch 1 according to the present embodiment includes a case 2 as a box-shaped housing as a whole, a microswitch 3 as a switching means provided on the upper part of the case 2, and a case 2. a diaphragm assembly 4 fixed to the lower part of the diaphragm assembly 2. The pressure switch 1 also includes an actuating member 5 that is supported to be movable up and down with respect to the diaphragm assembly 4 and a transmission mechanism 6 that transmits movement of the actuating member 5 to the microswitch 3. Further, the pressure switch 1 includes a leaf spring 7 that biases the diaphragm (pressure sensitive member) 44 of the diaphragm assembly 4 to apply an initial compressive force, and a leaf spring adjustment means 8 that adjusts the biasing force of the leaf spring 7. Equipped with

The case 2 includes a base body 21 made of metal, a box body 22 that holds the base body 21 inside, and a lid body 23 (support body) that is attached to cover the upper opening of the box body 22. The base body 21 is integrally formed with a cylindrical portion 21a having a cylindrical shape with a bottom and a flat plate portion 21b extending horizontally outward continuously from the upper end of the cylindrical portion 21a. The diaphragm assembly 4 is supported inside the cylindrical portion 21a, and a joint member P included in the diaphragm assembly 4 is exposed to the outside through an opening provided at the center of the bottom surface of the cylindrical portion 21a.

The lid body 23 is made of insulating resin. This lid body 23 is formed to have a top plate portion 23a, an annular portion 23b, and a hanging piece portion 23c. The top plate portion 23a is a wall portion to which the microswitch 3 is attached, and the annular portion 23b is a square annular portion inserted into the box body 22 along the side surface portion 22b. Further, the hanging piece portions 23c are portions that extend downward from the four corners of the annular portion 23b and come into contact with the flat plate portion 21b of the base body 21. With such a hanging piece portion 23c, the assembly can be performed so that the stroke of the transmission member 62, which will be described later, is stabilized. The annular portion 23b is provided with a locking claw 23d that locks into the locking portion 22c of the box body 22. An annular water stop member 24 is provided on the inner surface of the side surface portion 22b of the box body 22 and is in close contact with the annular portion 23b.

The box body 22 is formed into a rectangular tube shape as a whole, and the base body 21 is held by a tube-shaped portion 21a inserted through a circular opening provided in a bottom surface portion 22a. A plurality of locking portions 22c for locking with the lid body 23 are formed on the side surface portion 22b of the box body 22.

The microswitch 3 is provided inside the lid 23 of the case 2, and moves between a pair of fixed electrodes 31, 32 that are vertically opposed inside the lid 23, and between the upper and lower fixed electrodes 31, 32. It includes a movable electrode 33 that can be freely provided. Further, the microswitch 3 has a conductive structure formed by a pair of first terminals 34, 34' connected to a pair of fixed electrodes 31, 32 and extending outside the lid body 23, and a plate spring to which a movable electrode 33 is joined. A member 35 is provided. Further, the microswitch 3 includes a second terminal 36 connected to the conductive member 35 and extending outside the lid 23, and an adjustment screw 37 for adjusting the position of the upper fixed electrode 31. The conductive member 35 includes a conductive piece 35a that extends from the second terminal 36 and has the movable electrode 33 fixed to its tip, a movable piece 35b that extends from the second terminal 36 and has the transmission mechanism 6 connected to its intermediate part, and a movable electrode. 33 to either of the fixed electrodes 31, 32. As will be described later, the displacement of the diaphragm 44 is transmitted to the movable piece 35b via the transmission mechanism 6, and the movable piece 35b is moved in accordance with this displacement. This microswitch 3 has two states: a low voltage state in which the movable electrode 33 contacts the upper fixed electrode 31 and the two are electrically connected, and a high voltage state in which the movable electrode 33 contacts the lower fixed electrode 32 and electrically conducts between them. , to detect. The microswitch 3 is configured to switch the conduction state between the pair of first terminals 34, 34' and the second terminal 36 by switching the conduction state according to the displacement of the diaphragm 44 in this way. There is.

The diaphragm assembly 4 includes a lower holding plate 42 supported by the cylindrical portion 21a of the base body 21, a spacer 43 held between the upper holding plate 41 and the lower holding plate 42, a diaphragm 44, a bottom plate member 45, and An upper holding plate 41 is provided. The upper holding plate 41 is formed into a disk shape as a whole, and has an insertion hole 41a that vertically passes through the center thereof and through which the actuating member 5 is inserted and guided vertically. The lower holding plate 42 is formed into a cylindrical shape as a whole, and includes a stepped portion 42a for holding the spacer 43, the diaphragm 44, and the bottom plate member 45, and a crimping portion extending upward for crimping and fixing the upper holding plate 41. A tightening piece 42b is formed. In the diaphragm assembly 4, a spacer 43, a diaphragm 44, and a bottom plate member 45 are sandwiched between the upper holding plate 41 and the step portion 42a of the lower holding plate 42. By crimping the crimping pieces 42b inward, the peripheral edges of the diaphragm 44 and the bottom plate member 45 are held between the upper holding plate 41 and the lower holding plate 42.

The diaphragm 44 is formed in the overall disk shape by stacking a plurality of metal thin plates, and has a dome-shaped convex portion 44a that is convex upward in a natural state. The bottom plate member 45 is formed from a metal plate in the shape of a disk as a whole into a dish shape with a central portion bulging downward, and a through hole 45a to which the joint member P is fixed is formed in the central portion. The diaphragm 44, the bottom plate member 45, and the spacer 43 are joined to each other by welding or the like to ensure airtightness and pressure resistance. In this diaphragm assembly 4, a high pressure chamber 46 is formed by a space surrounded by the diaphragm 44 and the bottom plate member 45, and high pressure fluid flows into this high pressure chamber 46 via the joint member P. Further, a low pressure chamber 47 is formed by the space surrounded by the diaphragm 44, the spacer 43, and the upper holding plate 41, and this low pressure chamber 47 is communicated with the internal space of the box body 22 through the insertion hole 41a. The internal pressure is equal to atmospheric pressure. Therefore, the diaphragm 44, which is a pressure-sensitive member, is configured to move up and down in response to pressure fluctuations of the high-pressure fluid flowing into the high-pressure chamber 46. In this way, the diaphragm 44 partitions the low pressure chamber 47 and the high pressure chamber 46, and serves as a pressure sensitive member that is displaced by pressure fluctuations in the high pressure chamber 46.

The leaf spring 7 has one end 71 fixed to the base body 21 and the other end 72 connected to the leaf spring adjusting means 8. An insertion hole 73 through which the second shaft portion 53 of the actuating member 5 is inserted is provided at approximately the center of the leaf spring 7 in a plan view, and a portion of the enlarged diameter portion 52 of the actuating member 5 is provided on the lower surface of the periphery of the insertion hole 73. The upper surfaces of the parts are in contact with each other. The leaf spring adjustment means 8 includes an adjustment screw 81 that passes through the flat plate portion 21b of the base body 21, and a slider 82 that is provided in contact with the upper surface of the leaf spring 7 and is screwed into the adjustment screw 81 that passes through the leaf spring 7. . The adjustment screw 81 can be rotated from the lower side of the flat plate portion 21b before assembling the box body 22 and the base body 21, and the slider 82 is supported inside the case 2 so as to be non-rotatable and slidable up and down. There is. The slider 82 is configured to move up and down by rotating the adjustment screw 81. Therefore, when the adjustment screw 81 is tightened to move the slider 82 downward, the other end 72 of the leaf spring 7 is lowered, and when the adjustment screw 81 is loosened and the slider 82 is moved upward, the other end 72 of the leaf spring 7 is moved downward. The end portion 72 is raised, thereby adjusting the biasing force of the leaf spring 7. The biasing force of the leaf spring 7 is transmitted to the diaphragm 44 via the actuating member 5, and the convex portion 44a of the diaphragm 44 is pressed downward, thereby applying an initial compressive force. Further, by adjusting the urging force of the leaf spring 7, the pressing force of the diaphragm 44 can be adjusted, and the range of pressure values to be detected can be adjusted.

The actuating member 5 includes a first shaft portion 51 that extends vertically and is inserted into the insertion hole 41a of the upper holding plate 41, and an enlarged diameter portion 52 that expands in diameter in the horizontal direction along the upper surface of the upper holding plate 41. A second shaft portion 53 extends upward from the enlarged diameter portion 52. The actuating member 5 is supported so that the first shaft portion 51 can move forward and backward in the vertical direction by being guided by the insertion hole 41a, and the lower end of the first shaft portion 51 is in contact with the center of the convex portion 44a of the diaphragm 44. It is set in. Therefore, the actuating member 5 moves up and down with the displacement of the diaphragm 44, and the actuating member 5 receiving the urging force of the leaf spring 7 urges the diaphragm 44 toward the high pressure chamber 46, so that the diaphragm 44 is initialized. The compressive force is configured to apply a compressive force.

The enlarged diameter portion 52 is provided so that its lower surface can come into contact with the upper surface of the upper holding plate 41, and is provided to restrict movement of the actuating member 5 below this contact position. Therefore, the diaphragm 44 is restricted from moving beyond the initial compressed state toward the high pressure chamber 46 . Further, the upper end of the second shaft portion 53 is chamfered into a spherical shape, and this upper end comes into contact with a connecting member 61 of the transmission mechanism 6, which will be described later.

The transmission mechanism 6 includes a connecting member 61 made of a metal plate, a transmitting member 62, and a shaft member 63 that rotatably supports the connecting member 61. The connecting member 61 is disposed oppositely above the diaphragm assembly 4 with the leaf spring 7 in between, and is contacted by the second shaft portion 53 of the actuating member 5 from below, and is connected to the transmitting member 62. This connecting member 61 is rotatably supported by a shaft member 63 relative to the base body 21 . The transmission member 62 extends upward from the connection member 61, and its upper end engages with the movable piece 35b of the conduction member 35 of the microswitch 3.

In this transmission mechanism 6, a transmission member 62 receives displacement of the diaphragm 44 via the actuating member 5 and the connecting member 61. The transmission member 62 receives this displacement and moves in the advance/retreat direction D11 corresponding to the vertical direction in the figure, thereby transmitting the displacement to the movable piece 35b of the conductive member 35 in the microswitch 3, which is a subsequent stage part.

Here, in this embodiment, since the microswitch 3 has the snap piece 35c, assuming that it does not include the positioning means 9 related to the reset operation described later, It works as follows.

That is, under the above-mentioned assumption, when the transmission member 62 advances to the first position on the advancing side (upper side) than the limit position that the snap piece 35c can withstand in the advance/retreat direction D11, the first state becomes conductive to the second state. Switch state. The first state is a state in which the movable electrode 33 is in contact with the upper fixed electrode 31, and the second state is a state in which the movable electrode 33 is in contact with the lower fixed electrode 32. The pressure switch 1 of this embodiment is a high-pressure cutoff switch that switches the conduction state from the first state to the second state when abnormally high pressure occurs in the high pressure chamber 46.

Under the above-mentioned assumption, after this switching, that is, when returning to the first state before switching after cutoff, the transmission member 62 reaches the second position on the regressive side (lower side) than the first position. Upon regression, the conduction state is switched from the second state described above to the first state. In other words, this microswitch 3 has two positions: the first position (operating point), which is the set value as a trigger to execute high voltage cutoff, and the second position (return point), which is the set value as a trigger to return to the original state. , is a mismatched switch.

In this embodiment, the pressure switch 1 is configured to maintain a second state in which the movable electrode 33 is in contact with the lower fixed electrode 32 when a high-pressure cutoff occurs, for subsequent maintenance work by the operator. Positioning means 9 is provided as a member for maintaining. Further, a reset means 10 is provided for canceling the maintenance of the second state and returning to the first state before cutoff, in which the movable electrode 33 is in contact with the upper fixed electrode 32.

As shown in FIG. 3, the positioning means 9 sets the position of the transmission member 62 in the advance/retreat direction D11, which is indicated by a dotted line in the figure, into a first position serving as a cut-off operating point and a second position serving as a return point. This is a member that can be releasably positioned halfway between the This positioning is performed via the connecting member 61 which together with the transmitting member 62 forms the transmitting mechanism 6 . In FIG. 3, a diagram with the reset means 10 removed so that the positioning means 9 can be seen and a diagram showing both the positioning means 9 and the reset means 10 are shown side by side.

The connecting member 61 is a rotary member whose one end side 611 is rotatably supported around a central axis 63a along the shaft member 63, and whose other end side 612 is movable in the forward/backward direction D11. The transmission member 62 is connected to a position away from the central axis 63a, and rotates in response to the displacement of the diaphragm 44 at an intermediate position 614 between the central axis 63a and the connection point 613 of the transmission member 62, thereby transmitting the transmission member 62. It is moved in the advance/retreat direction D11.

The positioning means 9 comes into contact with the back surface of the other end side 612 of the connecting member 61 facing the retreating side (lower side) in the advancing/retreating direction, and pushes up the other end side 612 toward the advancing side (upper side) in the advancing/retreating direction D11. Then, the other end side 612 is positioned at a position corresponding to the above-mentioned midway position of the transmission member 62.

As shown in FIGS. 3 and 4, this positioning means 9 includes a belt-shaped plate member 90 and a position adjustment screw that adjusts the position of the plate member 90 to position the transmission member 62 in the advance/retreat direction D11. 11. That is, the positioning means 9 is pre-adjusted so as to position the transmission member 62 at the above-mentioned intermediate position. A position adjustment screw 11 is provided as an adjustment means for making adjustments. The plate member 90 is a sheet metal processed component formed by bending a metal plate, and has a contact portion 91 and a flat portion 92. The position adjustment screw 11 is arranged so that its top part engages with a flat part 92 (specifically, a recessed part 92b to be described later).

The abutment portion 91 of the positioning means 9 is formed by being folded and connected from approximately the center of the plane portion 92 in the longitudinal direction. The contact portion 91 extends in the advance/retreat direction D11 and is capable of falling in a direction D12 intersecting the advance/retreat direction D11, that is, in a bending back direction in sheet metal processing. Then, as shown in FIG. 2, the connecting member 61 comes into contact with the back surface of the other end side 612 of the connecting member 61 in an upright state slightly tilted toward the outer wall.

Furthermore, one end of the flat part 92 is a fixed end 921 that is screwed to the flat plate part 21b of the base body 21 by a fixing screw 901, and the other end is a free end 922 that is movable in the advance/retreat direction D11. A fixing hole 921a into which a fixing screw 901 is inserted is provided on the fixed end 921 side of the flat portion 92. Further, a slit 923 is formed in the flat portion 92, which serves as a fulcrum for bending the flat portion 92 during preliminary adjustment using the position adjustment screw 11 described above.

In the case of this embodiment, the planar portion 92 is provided with a convex portion 92a serving as a reinforcing rib extending along the longitudinal direction. The back surface side of the convex portion 92a has a concave portion 92b corresponding to the shape of the convex portion 92a. The top of the position adjustment screw 11 is engaged with the recess 92b. In other words, the recessed portion 92b can guide the top portion of the position adjustment screw 11 to be engaged along the longitudinal direction of the flat portion 92 according to the adjustment amount (screwing amount) of the position adjustment screw 11.

Here, it is preferable that the convex portion 92a and the concave portion 92b are provided in the plane portion 92 from the vicinity of the slit 923 to the free end 922 that does not overlap the portion to which the position adjustment screw 11 is engaged. This is because if the terminal end of the recess 92b overlaps the part to which the position adjustment screw 11 is engaged, the position adjustment screw 11 will be removed from the guide lane by the recess 92b during the preliminary adjustment using the position adjustment screw 11 described above. This is because the above-mentioned advance adjustment may become difficult due to dislodging or getting caught. Thus, by providing the convex portion 92a and the concave portion 92b, it is possible to ensure the strength of the plate member 90 from the bending fulcrum described above to the portion where the top of the position adjustment screw 11 is engaged. Note that the amount of protrusion of the convex portion 92a (that is, the depth of the concave portion 92b) is equivalent to the thickness of the plate member 90 because the moment of inertia of the area approaches the third power when the thickness of the plate member 90 is doubled. It is preferable that there be. Further, here, a case will be described in which only one convex portion 92a and one concave portion 92b are provided along the longitudinal direction approximately at the center of the flat portion 92, but if they can engage with the top of the position adjustment screw 11, A plurality of them may be provided. At this time, the convex portions 92a and the concave portions 92b serving as reinforcing ribs may be formed in a wavy shape in the lateral direction of the plane portion 92.

Furthermore, in the plate member 90 , a folded portion 93 is provided at one end in the lateral direction of the flat portion 92 and extends along the longitudinal direction of the flat portion 92 . The folded portion 93 is formed by bending one end of the flat portion 92 in the transverse direction, and serves to reinforce the plate member 90 similarly to the convex portion 92a. It is preferable that the folded portion 93 is provided from the vicinity of the slit 923 provided in the plane portion 92 to the free end 922, similarly to the convex portion 92a and the concave portion 92b. This makes it possible to ensure further strength of the plate member 90 from the aforementioned bending fulcrum to the portion where the top of the position adjustment screw 11 is engaged. In such a positioning means 9, when the positioning is canceled by the reset means 10 (see FIG. 3), the folded portion 93 is configured to abut against the flat plate portion 21b of the base body 21, which is the attachment portion of the plate member 90 in the case 2. It has become. That is, the folded portion 93 also serves to prevent the plate member 90 from rotating when the reset means 10 releases the positioning. Note that the length of the folded portion 93 in the advance/retreat direction D11 is preferably such that the tip of the folded portion 93 is below the lower surface (lowest part including the plate thickness) of the base body 21 after advance adjustment.

Further, the positioning means 9 is to be pre-adjusted so as to position the transmission member 62 at the above-mentioned intermediate position, and the pressure switch 1 of this embodiment has an adjustment for performing such pre-adjustment. A position adjustment screw 11 is provided as a means. The position adjustment screw 11 is a member that adjusts in what position the contact portion 91 of the positioning means 9 positions the transmission member 62 via the connection member 61 in the advancing/retreating direction D11, and the other end of the connection member 61 The contact position with respect to the side 612 is adjusted by moving forward and backward in the forward and backward direction D11. Specifically, the position adjustment screw 11 adjusts the contact position of the contact portion 91 with respect to the other end side 612 of the connecting member 61 by moving the free end 922 of the flat portion 92 of the positioning means 9 in the advance/retreat direction D11. It is moved forward and backward in the forward and backward direction D11. This position adjustment screw 11 is an adjustment screw that can be accessed only during the assembly process of the pressure switch 1.

The reset means 10 is a member that cancels the positioning of the transmission member 62 by the positioning means 9 and moves the transmission member 62 to a free state in which it can move in the advance/retreat direction D11. This reset means 10 releases the positioning of the transmission member 62 by separating the contact portion 91 of the positioning means 9 from the back surface of the other end side 612 of the connecting member 61. That is, the reset means 10 separates the contact portion 91 from the back surface of the other end side 612 by pressing the contact portion 91 in the upright state in the above-described intersecting direction D12 and causing it to fall.

As shown in FIG. 2, the reset means 10 has a unit configuration in which a cylindrical case 101 houses a reset button 102 as a rod-shaped part and a coil spring 103 as a biasing part. The reset button 102 extends in the cross direction D12 and presses the contact portion 91 of the positioning means 9 at one end. Coil spring 103 biases reset button 102 in a direction away from contact portion 91 .

Here, the box body 22 in the pressure switch 1 is a housing having a side surface portion 22b as a cylindrical outer wall in which the positioning means 9 described above is accommodated. The reset means 10 is fitted into a through hole 22b-1 provided in the side surface portion 22b at a position corresponding to the positioning means 9 so as to move from the side surface portion 22b toward the positioning means 9. A female thread is cut on the inner peripheral surface of the through hole 22b-1, and a male thread is cut on the outer peripheral surface of the cylindrical case 101 of the reset means 10. The unit-configured reset means 10 is attached by screwing into the through hole 22b-1. Further, a ring-shaped packing 104 is sandwiched between the inner peripheral surface of the cylindrical case 101 and the outer peripheral surface of the rod-shaped reset button 102, and the two are sealed to maintain airtightness.

Further, as shown in FIG. 1, two so-called crab-shaped pouch holes 10a are provided in a portion of the cylindrical case 101 of the reset means 10 that is exposed to the outside. The reset means 10 is screwed into the through hole 22b-1 by inserting a protrusion of a special tool into these pouch holes 10a and screwing the reset means 10 into the through hole 22b-1.

Here, the operation of the pressure switch 1 configured as described above will be explained with reference to FIGS. 5 and 6. Note that FIGS. 5 and 6 schematically show the operating states of the internal components of the pressure switch 1 shown in FIG. 2 and the switching operations of the microswitch 3 according to the operations of the internal components, respectively. . Regarding the switching operation of the microswitch 3, the position is indicated by "*" representing the transmission member 62 corresponding to the other end side 612 of the connecting member 61.

As shown in step S11 in FIG. 5, during normal operation before abnormal high pressure is generated, the contact portion 91 of the positioning means 9 moves the other end side 612 of the connecting member 61 to the advancing side (upper side) in the advance/retreat direction D11. is pushing up. As a result, the transmission member 62 is positioned at an intermediate position between the cut-off operating point P11 as the first position and the return point P12 as the second position on the regressive side (lower side). ing. This intermediate position is a reset adjustment position P13 adjusted by the positioning means 9 whose positioning is canceled by the reset means 10. At the stage of step S11, the microswitch 3 is in a first state (ON state) in which the movable electrode 33 is in contact with the upper fixed electrode 31, as shown in FIG. 2, before cutoff.

Next, as shown in step S12, when abnormally high pressure is generated, the connecting member 61 is rotated by the displacement of the diaphragm 44 via the actuating member 5. As a result, the transmission member 62 connected to the other end side 612 of the connecting member 61 moves in the advancing direction D111 of the advance/retreat direction D11 to the operating point P11. In response to this, the conduction state of the microswitch 3 is switched to a second state (OFF state) in which the movable electrode 33 is in contact with the lower fixed electrode 31. At this time, the other end side 612 of the connecting member 61 separates from the contact portion 91 of the positioning means 9.

Thereafter, when the pressure decreases as shown in step S13, the connecting member 61 receives the displacement of the diaphragm 44 via the actuating member 5 and rotates in the opposite direction to that when the pressure increases. As a result, the transmission member 62 moves in the retraction direction D112 of the advance and retraction direction D11. However, the movement at this time is stopped when the other end side 612 of the connecting member 61 comes into contact with the contact portion 91 of the positioning means 9. As a result, the transmission member 62 is positioned at the reset adjustment position P13 on the advancing side of the return point P12 in the advance/retreat direction D11, and the conduction state of the microswitch 3 is not switched. As a result, the second state (OFF state) at the time of pressure increase is maintained. Based on the conduction state of the microswitch 3, workers such as maintenance personnel recognize that abnormally high pressure has occurred, even if the pressure has dropped at that time, and perform predetermined maintenance work. It happens.

After the maintenance work is completed, a reset operation is performed to return the conduction state of the microswitch 3 to the first state (ON state) in step S11.

First, as shown in step S14 in FIG. 6, the operator presses the reset button 102 in the reset means 10 in the cross direction D12. Then, the reset button 102 pushes the abutment portion 91 of the positioning means 9, causing it to fall in the falling direction D121. Due to this fall, the positioning of the transmission member 62 via the other end side 612 of the connecting member 61 by the contact portion 91 is released, and the transmission member 62 descends in the retraction direction D112 of the advance and retraction direction D11 without being interfered with by the positioning means 9. . This descent proceeds past the aforementioned return point P12 to the initial position before being positioned by the positioning means 9. This initial position becomes a pre-reset adjustment position P14 before the transmission member 62 is positioned at the reset adjustment position P13 by the adjustment procedure described later. Since this pre-reset adjustment position P14 is located on the backward side of the return point P12 in the advance/retreat direction D11, the conduction state of the microswitch 3 returns to the first state (ON state). At this stage, there is a gap between the contact portion 91 of the positioning means 9 and the other end side 612 of the connecting member 61, so that the transmission member 62 is in a free state capable of moving in the advance/retreat direction D11. .

Thereafter, as shown in step S15, when the operator releases the pressure on the reset button 102 in the reset means 10, the reset button 102 returns in the direction of arrow D122 due to the bias of the coil spring 103. As a result, the contact portion 91 of the positioning means 9 returns to the position corresponding to the reset adjustment position P13 in the direction of arrow D123 due to its own rigidity. The restored contact portion 91 pushes up the other end side 612 of the connecting member 61 from the back side, and in response to this, the transmission member 62 moves in the advancing direction D111 of the advance/retreat direction D11 and returns to the reset adjustment position P13. be positioned. Since this reset adjustment position P13 is on the retreating side (lower side) of the operating point P11 in the advancing/retreating direction D11, the conduction state of the microswitch 3 is not changed by the movement of the transmission member 62 at this time, but is in the first state (ON state). ) is maintained. At this stage, the process returns to the state of step S11 in FIG. 5 described above.

Here, as described above, positioning of the transmission member 62 to the reset adjustment position P13 is performed by advance adjustment using the position adjustment screw 11 shown in FIG. The procedure for this preliminary adjustment will be described below with reference to FIGS. 7 and 8. 7 and 8 also schematically show the operating states of the internal components of the pressure switch 1 shown in FIG. 2, and the switching operation of the microswitch 3 according to the operations of the internal components, respectively. Regarding the switching operation of the microswitch 3, the position is indicated by "*" representing the transmission member 62 corresponding to the other end side 612 of the connecting member 61, and the position is indicated by "x" representing the positioning means 9, that is, In this positioning means 9, the position of a contact portion 91 that contacts and moves the other end side 612 of the connecting member 61 is shown.

First, in the unadjusted stage shown in step S21 in FIG. 7, the positioning screw 11 is recessed, as shown in FIG. It is located in an unadjusted position where it contacts, and is separated from the back surface of the other end side 612 of the connecting member 61. As a result, the transmission member 62 is located at the pre-reset adjustment position P14, which is on the retreating side of both the operating point P11 and the return point P12 in the advance/retreat direction D11.

In step S22, which is the first stage of adjustment, the connecting member 61 is forcibly moved and the transmission member 62 is moved in the advancing direction D111 of the advancing and retreating directions D11. This forced movement of the transmission member 62 via the connecting member 61 brings about an operating point P11 at which the conduction state of the microswitch 3 switches to the second state (OFF state) in which the movable electrode 33 is in contact with the lower fixed electrode 31. You can continue until you exceed it. During this time, the positioning means 9 remains stationary in the unadjusted position. Here, in this embodiment, the forced movement of the transmission member 62 is performed by directly accessing and moving the connecting member 61. However, the method of forcibly moving the transmission member 62 is not limited to this, for example, a method of moving the connecting member 61 via the diaphragm 44 and the actuating member 5 by forcibly increasing the internal pressure of the high pressure chamber 46, etc. It's okay to have one.

In step S23 of the second stage, the position adjustment screw 11, which is an adjustment screw, is screwed in the advancing direction D111, and the positioning means 9 advances in the advancing direction D111. The screwing of the position adjustment screw 11 is continued until the contact portion 91 of the positioning means 9 comes into contact with the back surface of the other end side 612 of the connecting member 61 that positions the transmission member 62 at the operating point P11. During this time, the connecting member 61 is restrained and its position is maintained, thereby keeping the transmission member 62 at a position beyond the operating point P11.

As shown in FIG. 8, in step S24 of the third stage, the restraint of the connecting member 61 is released, the positioning screw 11 is returned to the retracting direction D112, and the positioning means 9 is retracted in the retracting direction D112, Following this, the connecting member 61 moves and the transmitting member 62 retracts. The return of the position adjustment screw 11 is continued until the transmission member 62 reaches the return point P12 where the conduction state of the microswitch 3 is switched to the first state (ON state) where the movable electrode 33 is in contact with the upper fixed electrode 31. . The operation in step S24 of the third stage is an operation of moving the positioning means 9 to search for the position of the return point P12.

In step S25 of the fourth and final stage, the positioning screw 11 is screwed in the advancing direction D111 opposite to step S24, the positioning means 9 advances in the advancing direction D111, and the connecting member 61 moves following this. The transmission member 62 advances from the return point P12 toward the operating point P11. At this time, the screwing of the position adjustment screw 11 is stopped before the transmission member 62 reaches the operating point P11. The screwing amount at this time is a screwing amount predetermined based on the screw pitch and the like. Thereby, the transmission member 62 is positioned at the reset adjustment position P13, which is an intermediate position between the operating point P11 and the return point P12, and the preliminary adjustment is completed.

According to the pressure switch 1 of the embodiment described above, the flat part 92 of the plate member 90 in the positioning means 9 is provided with the convex part 92a extending and arranged along the longitudinal direction, so that the positioning The strength of the means 9 can be improved, it can be made difficult to bend, and the occurrence of warping and distortion can be suppressed.

Further, according to the pressure switch 1 of the present embodiment, the back side of the convex portion 92a of the flat portion 92 has a concave portion 92b corresponding to the shape of the convex portion 92a, and this concave portion 92b is provided with a position adjustment screw. The tops of 11 are engaged. This improves the seating of the position adjustment screw 11 and suppresses the occurrence of variations such as errors and fluctuations in the operating value (reset adjustment position). Further, since a folded portion 93 extending along the longitudinal direction is provided at one end in the transverse direction of the flat portion 92 of the plate member 90, when the positioning is canceled by the reset means 10, The folded portion 93 contacts the flat plate portion 21b of the base body 21, which is the attachment portion of the plate member 90 in the case 2, and can prevent rotation of the positioning means 9. Therefore, it is possible to suppress fluctuations in the adjustment position of the positioning means 9 and prevent variations in the operating value, thereby improving the adjustment accuracy by the positioning means 9. Thus, the pressure switch 1 of this embodiment can operate accurately.

Here, it is preferable that the folded portion 93 is formed by bending one end of the flat portion 92 in the lateral direction. According to this configuration, the strength of the flat portion 92 can be further improved, and since the folded portion 93 is configured integrally with the flat portion 92, an increase in the number of parts can be avoided.

In addition, in the pressure switch 1 of the present embodiment, the rotary member is rotatably supported around a central shaft 63a disposed at one end, and the other end is movable in the advance/retreat direction D11, and is spaced apart from the central shaft 63a. The transmission member 62 is connected to the position where the transmission member 62 is connected, and the transmission member 62 is rotated in the forward/backward direction D11 by receiving displacement of the pressure sensitive member at an intermediate position 614 between the central axis 63a and the connection point of the transmission member 62. The positioning means 9 includes a member 61, and further includes a contact portion 91 that extends from a plane portion 92 in the advancing/retreating direction D11 and comes into contact with the back surface of the other end side 612 of the connecting member 61, and the plane portion 92 includes: One end is a fixed end 921 and the other end is a free end 922 movable in the forward/backward direction D11, and by moving the free end 922 in the forward/backward direction D11, the position adjustment screw 11 is brought into contact with the other end side 612 of the connecting member 61. It is preferable to move the contact position of the contact portion 91 forward and backward in the forward and backward direction D11.

According to such a configuration, by adjusting the contact position of the positioning means 9 with respect to the other end side 612 of the connecting member 61 by advancing and retreating, which is an easy-to-operate method, the positioning means 9 can adjust the contact position of the transmission member 62 midway. Positioning can be performed reliably. Furthermore, since strict component size management is not required, increases in component prices can be suppressed. Furthermore, with the good operability of moving the free end 922 of the flat portion 92, the contact position, and by extension the positioning means 9, can reliably position the transmission member 62 at an intermediate position. .

Note that the embodiments described above merely show typical forms of the present invention, and the present invention is not limited thereto. That is, various modifications can be made without departing from the gist of the invention. Of course, such modifications fall within the scope of the present invention as long as they still have the configuration of the pressure switch of the present invention.

For example, in the embodiment described above, as an example of a pressure switch, a pair of first terminals 34, 34' and a second terminal 36 are provided, and by switching the conduction state of the microswitch 3 as a switching means, these three terminals are A pressure switch 1 that switches between ON and OFF is illustrated. However, the pressure switch is not limited to this, and the specific switch configuration can be set as appropriate, such as how to switch the conduction state between the terminals by changing the number of terminals and the conduction state of the switching means. .

Further, in the above-described embodiment, as an example of a pressure switch, the positioning means 9 abuts against the back surface of the other end side 612 opposite to the pivotally supported one end side 611 of the connecting member 61 and pushes up the transmitting member 62. A pressure switch 1 for positioning is illustrated. Further, in this embodiment, the reset means 10 releases the positioning by separating the positioning means 9 from the connecting member 61. However, the specific configurations for positioning the transmission member by the positioning means and for canceling the positioning by the reset means are not limited to these, and can be set arbitrarily. However, by positioning via the connecting member 61 or by releasing the positioning by separating the positioning means 9 from the connecting member 61, the transmission member can be separated from the resetting means to effectively avoid deviations in set values in the reset state. The points that can be performed are as described above.

Further, in the above-described embodiment, as an example of a pressure switch, the reset means 10 presses the contact portion 91 of the positioning means 9 and overturns it, thereby separating it from the connecting member 61 and releasing the positioning with respect to the transmission member 62. A pressure switch 1 is illustrated. However, the specific structure for separating the positioning member from the connecting member is not limited as long as separation is possible. However, as described above, by employing a configuration in which the abutting portion 91 is turned over, it can be effectively separated from the connecting member.

Further, in the above-described embodiment, as an example of the pressure switch, the pressure switch 1 in which the reset means 10 includes the reset button 102 as a rod-shaped portion and the coil spring 103 as the biasing portion is illustrated. However, the reset means is not limited to this, and its specific configuration is not critical as long as it can be turned over by pressing the contact portion of the positioning means. However, as described above, the operability of the reset means can be improved by having a configuration having a rod-shaped portion and a biasing portion.

Further, in the above-described embodiment, the pressure switch 1 in which the reset means 10 is fitted and attached to the through hole 22b-1 provided in the side surface 22b of the box body 22 is illustrated as an example of the pressure switch. However, the mounting structure of the reset means is not limited to this, and a structure such as using a part of the housing of the pressure switch as a case for the reset means may be used. However, as described above, by adopting a configuration in which the reset means 10 is fitted into the through hole 22b-1, the attachment can be easily performed. Further, as described above, an auto-reset type pressure switch can be easily constructed by closing the through hole 22b-1 with a cover member without attaching the reset means 10. Further, in this embodiment, two so-called crab-shaped pouch holes 10a are opened in the externally exposed part of the reset means 10, and a special tool is inserted into the pouch holes 10a to tighten the structure. There is. However, the reset means is not limited to this configuration, and may have a structure in which the externally exposed portion has no blind hole and the outer periphery is polygonal, such as a regular hexagon, and is fastened with a general-purpose tool such as a box wrench. Furthermore, the reset means may have a structure in which a flat surface is formed by cutting a part of the cylindrical part exposed to the outside in parallel, and the reset means is tightened using a general-purpose tool such as a spanner. The method of fixing the reset means is appropriately selected depending on ease of assembly, fixing strength, etc.

1 Pressure switch 2 Case 22 Box 22b Side part (outer wall)
22b-1 Through hole 3 Micro switch 31, 32 Fixed electrode 33 Movable electrode 34, 34' First terminal 35 Conductive member 36 Second terminal 4 Diaphragm assembly 44 Diaphragm (pressure sensitive member)
5 Operating member 6 Transmission mechanism 61 Connection member 611 One end side 612 Other end side 62 Transmission member 63 Shaft member 63a Central shaft 7 Leaf spring 8 Leaf spring adjusting means 9 Positioning means 90 Plate member 91 Contact portion 92 Plane portion 92a Convex portion 92b Recessed portion 921 Fixed end 922 Free end 923 Slit 93 Folded portion 10 Reset means 101 Cylindrical case 102 Reset button 103 Coil spring 104 Packing 11 Position adjustment screw D11 Forward/backward direction D12 Crossing direction P11 Operating point P12 Return point P13 Reset adjustment position (midway position)
P14 Position before reset adjustment

Claims (3)

Provided inside the housing,
a pressure-sensitive member that partitions a low-pressure chamber and a high-pressure chamber and is displaced due to pressure fluctuations in the high-pressure chamber;
a transmission member that receives the displacement of the pressure-sensitive member and moves in a preset advance/retreat direction to transmit the displacement to a subsequent part;
Regarding the advance/retreat direction, when the transmission member advances to the first position, the conduction state is switched from the first state to the second state, and when the transmission member regresses to the second position on the retreat side from the first position, the conduction state is switched from the first state to the second state. a switching means for switching a conductive state from the second state to the first state;
positioning means for releasably positioning the transmission member in the advance/retreat direction at an intermediate position between the first position and the second position;
Resetting means for canceling the positioning of the transmission member by the positioning means and shifting the transmission member to a free state in which it is movable in the advance and retreat directions;
The positioning means includes a belt-shaped plate member, and a position adjustment screw that adjusts the position of the plate member to position the transmission member in the advancing and retreating direction,
The planar portion of the plate member is provided with a convex portion extending along the longitudinal direction, and the back side of the convex portion forms a concave portion corresponding to the shape of the convex portion,
A folded part extending and arranged along the longitudinal direction is provided at one end in the transverse direction of the flat part of the plate member,
The top of the position adjustment screw is engaged with the recess,
When the positioning is released by the reset means, the folded portion comes into contact with a mounting portion of the plate member in the casing. The pressure switch according to claim 1, wherein the folded portion is formed by bending one end of the flat portion in the lateral direction. A rotary member is rotatably supported around a central axis disposed at one end, and the other end is movable in the advancing and retracting directions, and the transmitting member is connected to a position apart from the central axis, and a connecting member that rotates in response to displacement of the pressure-sensitive member at an intermediate position between a shaft and a connecting point of the transmitting member to move the transmitting member in the advancing and retracting direction;
The positioning means further includes an abutting portion extending from the plane portion in the advancing/retracting direction and abutting on a back surface of the other end of the connecting member facing the retreating side in the advancing/retracting direction;
The plane part has one end fixed and the other end a free end movable in the advancing and retreating direction,
3. The position adjustment screw moves the free end in the forward/backward direction to advance or retreat the contact position of the contact portion with respect to the other end of the connecting member in the forward/backward direction. pressure switch.

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