Pushbutton Switch

Abstract

To provide a push-button switch in which the number of packings is reduced and the packings are prevented from being dropped / lost.SOLUTION: A push-button switch 10 comprises: a frame 16; a flange 34 protruding from the frame 16; eight protrusions 36 protruding from the flange 34; and an annular packing 24. The packing 24 includes: an inner peripheral end 42; a first annular part 44 which abuts on and seals a surface of the flange 34 by being pressed with an inner peripheral wall 40; a movable relay part 48; a second annular part 46 which is held between a panel P and the flange 34 by screwing a nut 28 to a screw part 32, thereby sealing a gap between the panel and the flange; a side face part 50 connecting the first annular part 44 and the second annular part 46 at an outer peripheral side; and a plurality of holes 52 which are formed on the side face part 50, have the protrusions 36 inserted therethrough and protrude to the outer peripheral side. An outer peripheral wall 38 of a cylindrical member 22 is engaged with the protrusions 36.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a push button switch that is fixed to a mounting hole in a panel and operates a contact portion provided on the back side of the panel when an operator provided on the front side of the panel is operated. [Background technology]

[0002] A pushbutton switch is fixed in a mounting hole in a panel such as a control panel. The pushbutton switch has a cylindrical member on the front side of the panel, and when an operator located on the inner periphery of the cylindrical member is pressed, a push rod is pushed out, which acts on a contact portion located on the back side of the panel.

[0003] Control panels on which pushbutton switches are installed are used to control machine tools and the like, and are often exposed to oil. Therefore, it is desirable to provide a gasket to prevent oil from seeping inside. To prevent this, the pushbutton switch described in Patent Document 1 has a gasket (also called a first gasket) between the tubular member and the push rod. It is also desirable to provide a gasket (also called a second gasket) between the tubular member and the panel surface to prevent oil. The second gasket, as in the switch described in Patent Document 2, is tightened by a nut threaded onto a threaded portion protruding from the mounting hole toward the rear surface, providing a seal. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-93821 [Patent Document 2] Japanese Patent Publication No. 2020-9534 Summary of the Invention [Problem to be solved by the invention]

[0005] As described above, it is desirable to provide a first gasket and a second gasket in order for the pushbutton switch mounted on the panel to have sufficient oil resistance. However, providing two gaskets increases the number of parts. Furthermore, the second gasket is separate from the cylindrical member, etc., and there is a concern that it may fall off or be lost when the pushbutton switch is mounted on or removed from the panel.

[0006] The present invention has been made in view of the above-mentioned problems, and has as its object to provide a push button switch that reduces the number of packings and prevents the packings from falling off or being lost. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems and achieve the object, a push button switch according to the present invention includes a push rod that is inserted into a mounting hole in a panel and protrudes to the back side of the panel, an operator that is manually pressed to push out the push rod, a cylindrical frame that is inserted into the mounting hole and arranged on the outer periphery of the push rod, a threaded portion formed on the outer periphery of the frame, a contact portion that is provided on the back side of the panel and changes the connection state of a contact in conjunction with the operation of the push rod, a nut that screws onto the threaded portion from the back side of the panel and abuts against the back surface of the panel, a flange that protrudes in the outer periphery direction from the frame on the front side of the panel, a plurality of protruding pieces that protrude radially from the outer periphery end face of the flange, and a contact portion that is provided on the front side of the panel and has an outer periphery wall with a plurality of projections. The panel fastener has a cylindrical member that engages with the protruding piece and has an inner peripheral wall that protrudes toward the surface of the panel, and an annular packing made of an elastic material, wherein the packing has an inner peripheral end that abuts against the outer peripheral surface of the push rod to seal, a first annular portion whose back surface abuts against the surface of the flange to seal when its front surface is pressed by the inner peripheral wall, a movable relay portion that connects the inner peripheral end and the first annular portion and is deformable in response to displacement of the push rod, a second annular portion that is sandwiched between the panel and the flange when the nut is screwed onto the threaded portion to seal between them, a side portion that connects the first annular portion and the second annular portion on the outer periphery, and a plurality of holes formed in the side portion through which the protruding piece is inserted. This makes it possible to reduce the number of packings and eliminates the risk of the packing falling off or being lost.

[0008] The protruding piece may have a first engagement protrusion protruding outward from a position on the outer peripheral end face closer to the front, and the outer peripheral wall may have a second engagement protrusion protruding inward from a position closer to the panel, and the tubular member may be fixed to the flange by engagement between the first engagement protrusion and the second engagement protrusion. This makes it possible to easily fix the tubular member to the flange.

[0009] The number of the protruding pieces and the holes corresponding to the protruding pieces may be 6 to 8. This makes it possible to reliably fix the flange and the tubular member, and also maintain the connection strength between the first annular portion and the second annular portion. [Effects of the Invention]

[0010] In the pushbutton switch according to the present invention, the inner peripheral end, movable relay part, first annular part, and second annular part are configured as a single packing, thereby reducing the number of parts. In addition, the second annular part is configured to be inseparable from the other parts, so it will not fall off or get lost. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a side view, partly in section, of a push button switch according to this embodiment. [Figure 2] FIG. 2 is an exploded perspective view of the push button switch according to the present embodiment. [Figure 3] FIG. 3 is a perspective view, partly in section, of the packing. [Figure 4] FIG. 4 is a perspective view of a part of the cylindrical member in cross section. [Figure 5] FIG. 5 is a perspective view, partly in section, of the frame, the push rod, and the packing in an assembled state. [Figure 6] FIG. 6 is an enlarged cross-sectional side view of a portion of the push button switch that does not include the protruding piece. [Figure 7] FIG. 7 is an enlarged cross-sectional side view of a portion including the protruding piece, taken at a different angle from that in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0012] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A push button switch according to an embodiment of the present invention will be described in detail below with reference to the accompanying drawings. However, the present invention is not limited to the embodiment.

[0013] Fig. 1 is a partial cross-sectional side view of a pushbutton switch 10 according to this embodiment. Fig. 2 is an exploded perspective view of the pushbutton switch 10. The pushbutton switch 10 is mounted in a circular mounting hole Pa in a panel P of a control panel or the like. Fig. 3 is a partial cross-sectional perspective view of a packing 24. Fig. 4 is a partial cross-sectional perspective view of a cylindrical member 22. Fig. 5 is a partial cross-sectional perspective view of a frame 16, a push rod 18, and a packing 24 assembled together.

[0014] The pushbutton switch 10 has an operating unit 12 that is attached to the panel P, and a contact unit 14 that is fixed to the operating unit 12 on the back side of the panel P. In the pushbutton switch 10, the operating unit 12 and the contact unit 14 are separate entities, but they may be integrated as long as the contact unit 14 is large enough to pass through the mounting hole Pa. The pushbutton switch 10 may be illuminated. The pushbutton switch 10 may be one in which the pressed state of the button is latched once and released when pressed again. In describing the pushbutton switch 10, the side with the contact unit 14 located relative to the panel P is referred to as the back, and the opposite side as the front. The back side relative to the panel P is the inside of the control panel, and it is desirable that oil and water do not enter.

[0015] The contact section 14 has a base 14a, a release arm 14b, and a contact block 14c. The base 14a has an attachment hole 14aa into which the body section 30, described later, is inserted. The release arm 14b is the part that acts when separating the operating section 12 from the contact section 14. The contact block 14c is a block that has contacts that switch between connected states in conjunction with the operation of the push rod 18, described later. The contact block 14c may be a unit type. The configuration of the contact section 14 is basically the same as that of the prior art, so a detailed description will be omitted.

[0016] The operating unit 12 has a frame 16, a push rod 18, an operator 20, a cylindrical member 22, a packing 24, a coil spring 26, and a nut 28. The frame 16 is the base of the operating unit 12 and has a body 30, a threaded portion 32, and a flange 34. The body 30 is cylindrical and is the portion that is inserted into the mounting hole Pa. An engagement portion 30a that fixes the contact portion 14 is formed at the rear end of the body 30. An annular spring seat 30b is provided on the inner peripheral surface of the body 30.

[0017] The threaded portion 32 is formed on the outer peripheral surface of the body portion 30 and is inserted into the mounting hole Pa together with the body portion 30. The flange 34 protrudes in the outer peripheral direction from the body portion 30, has a larger diameter than the mounting hole Pa, and is positioned on the front side of the panel P. The flange 34 has a diameter slightly larger than the mounting hole Pa. Eight protruding pieces 36 protrude radially at equal intervals from the outer peripheral end face of the flange 34.

[0018] The protruding pieces 36 are rectangular in plan view. The flange 34 and the protruding pieces 36 have the same thickness. When there are eight protruding pieces 36, assuming that the entire circumference of the flange 34 is 360 degrees, the width of the base of each protruding piece 36 is, for example, about 5 to 15 degrees, and more preferably about 10 degrees. The protruding length of the protruding pieces 36 is slightly greater than the thickness of the packing 24.

[0019] The push rod 18 is a cylinder that is inserted through the mounting hole Pa and protrudes to the back side of the panel P. A fixed disk 18a is provided at the front end of the push rod 18. An annular groove 18b is formed on the outer circumferential surface of the push rod 18 slightly behind the fixed disk 18a. An annular spring seat 18c is formed slightly behind the annular groove 18b. A coil spring 26 is inserted between the spring seat 18c and spring seat 30b and biases the push rod 18 to the front side. The push rod 18 is prevented from coming out by a stopper (not shown). The push rod 18 and the body 30 of the frame 16 are concentric on the inner circumferential side of the mounting hole Pa, and the body 30 and threaded portion 32 are positioned on the outer circumferential side of the push rod 18.

[0020] The operator 20 is a disk that is manually pressed and corresponds to a button. The operator 20 is fixed to the fixed disk 18a, and by pressing the operator 20, the push rod 18 is pushed out to the rear side against the coil spring 26.

[0021] The cylindrical member 22 is provided on the front side of the panel P and has an outer peripheral wall 38 that forms the outer periphery and an inner peripheral wall 40 that forms the inner periphery. The outer peripheral wall 38 and the inner peripheral wall 40 are connected on the front side and separated on the back side to form a gap 41 between them. Four small slits 38a are formed at equal intervals in the outer peripheral wall 38 (see FIG. 2). The slits 38a open to the back side. The outer peripheral wall 38, divided by the slits 38a, can be slightly elastically displaced outward. The inner peripheral wall 40 is an annular protrusion that protrudes toward the surface of the panel P. The operator 20 is disposed on its inner periphery, and serves as a displacement guide for the operator 20. The outer peripheral wall 38 is the part of the push button switch 10 that is visible from the front side of the panel P and covers the inner peripheral wall 40.

[0022] The packing 24 is membrane-shaped and made of a resin elastic material such as rubber, silicone, or the like. The entire packing 24 is made of the same material. The packing 24 has an inner peripheral end portion 42, a first annular portion 44, a second annular portion 46, a movable relay portion 48, and a side portion 50. Eight holes 52 are formed at equal intervals in the side portion 50.

[0023] The inner peripheral end 42 fits into the annular groove 18b of the push rod 18 and elastically abuts against it to form a seal. The inner peripheral end 42 displaces along with the push rod 18. The inner peripheral end 42 has a cross section that conforms to the annular groove 18b and is slightly thicker than the other portions. Other means such as a retaining ring or adhesive may be used to seal between the packing 24 and the push rod 18.

[0024] The first annular portion 44 and the second annular portion 46 are annular in shape. Relatively speaking, the first annular portion 44 is located on the front side and the second annular portion 46 is located on the back side, with a gap 54 formed between them. The first annular portion 44 and the second annular portion 46 are connected on their outer peripheries by a side portion 50. In other words, the gap 54 opens to the inner periphery. The flange 34 fits into the gap 54, and the thickness of both portions is approximately equal.

[0025] The outer diameters of the first annular portion 44 and the second annular portion 46 are slightly larger than the outer diameter of the flange 34. The inner peripheral surface of the side portion 50 abuts the outer peripheral surface of the flange 34. The inner diameter of the second annular portion 46 is approximately equal to the inner diameter of the mounting hole Pa. The inner diameter of the first annular portion 44 is slightly smaller than the inner diameter of the second annular portion 46 and slightly larger than the inner diameter of the flange 34. The radial widths of the first annular portion 44 and the second annular portion 46 are ensured to be long enough to provide a sufficient sealing effect against the front and back surfaces of the flange 34.

[0026] Fig. 6 is an enlarged cross-sectional side view of a portion of the push button switch that does not include the protruding piece 36. Fig. 7 is an enlarged cross-sectional side view of a portion that includes the protruding piece 36, viewed at a different angle from Fig. 6.

[0027] The movable relay portion 48 is a portion that connects the inner peripheral end portion 42 and the inner peripheral edge of the first annular portion 44. The movable relay portion 48 has a tapered shape that increases in diameter from the front side to the back side, and is deformable to absorb displacement of the push rod 18. The movable relay portion 48 may have, for example, a U-shaped cross section, as long as it can absorb displacement of the push rod 18. The cross section of the movable relay portion 48 is slightly arc-shaped in side view (see Figure 6), making it easier for the inner peripheral end portion 42 to fit perpendicularly into the annular groove 18b.

[0028] As shown in Figures 5 and 7, protruding pieces 36 are inserted into each hole 52. The protruding pieces 36 protrude slightly outward from the hole 52. The packing 24 is flexible, and in the process of assembling the push button switch 10, the protruding pieces 36 can be inserted into the hole 52 while the second annular portion 46 elastically expands. There does not need to be a sufficient seal between the protruding pieces 36 and the hole 52; making the hole 52 slightly larger than the cross section of the protruding pieces 36 makes assembly easier.

[0029] The protruding piece 36 has a first engagement protrusion 36a that protrudes outward from a location on the outer peripheral end face near the front. The outer peripheral wall 38 of the tubular member 22 has a second engagement protrusion 38b that protrudes inward from a location near the panel P. The tubular member 22 is fixed to the flange 34 by engagement between the first engagement protrusion 36a and the second engagement protrusion 38b. As described above, the outer peripheral wall 38 has a slit 38a formed therein, and when the tubular member 22 is pressed toward the panel P, the outer peripheral wall 38 can be displaced slightly radially outward, and the first engagement protrusion 36a and the second engagement protrusion 38b engage in a snap-fit ​​manner.

[0030] 6 and 7, the protruding length of the inner peripheral wall 40 is slightly shorter than that of the outer peripheral wall 38. The difference in protruding length between the two is slightly greater than the thickness of the flange 34 and slightly less than the combined thickness of the flange 34 and the first annular portion 44. The outer peripheral wall 38 protrudes to the same position as the rear surfaces of the flange 34 and the protruding piece 36, and does not interfere with the surface of the panel P even when the second annular portion 46 is compressed.

[0031] The first annular portion 44 has its front surface pressed by the inner circumferential wall 40, and its back surface abuts against the surface of the flange 34, thereby providing a seal. An inclined surface 40a is formed at the tip of the inner circumferential wall 40, forming an acute angle, which applies strong pressure locally to the first annular portion 44, thereby providing a reliable seal.

[0032] The nut 28 is threaded onto the threaded portion 32 from the back side of the panel P and abuts against the back surface of the panel P. When the nut 28 is threaded onto the threaded portion 32, the second annular portion 46 is sandwiched between the panel P and the flange 34, thereby sealing the gap between them.

[0033] In the pushbutton switch 10 configured as described above, the gap between the push rod 18 and the tubular member 22 is sealed by the inner peripheral end portion 42, first annular portion 44, and movable relay portion 48 of the packing 24. Therefore, oil or water will not seep into the back side of the panel P by running down the outer peripheral surface of the push rod 18 or the inner peripheral surface of the tubular member 22. In addition, the gap between the tubular member 22 and the panel P is sealed by the second annular portion 46 of the packing 24. Therefore, oil or water will not seep into the back side of the panel P by running down the outer peripheral surface of the tubular member 22 or the surface of the panel P. In this way, the pushbutton switch 10 provides excellent oil and water resistance.

[0034] Furthermore, the inner peripheral end portion 42, the first annular portion 44, and the movable relay portion 48, which provide a seal between the push rod 18 and the tubular member 22, and the second annular portion 46, which provides a seal between the flange 34 and the panel P, are connected by the side portion 50 to form a single packing 24. Therefore, two sealing functions can be obtained with a single packing 24, which reduces the number of parts.

[0035] The second annular portion 46 corresponds to the second packing described as the prior art. The second packing according to the prior art is designed to come off the threaded portion 32 if the nut 28 is not present, but the second annular portion 46 of the present application does not come off the threaded portion 32, and there is no concern that it will fall off or be lost when the push button switch 10 is attached to or removed from the panel P.

[0036] Furthermore, manufacturers generally use the same material for the part that provides the sealing between the push rod 18 and the cylindrical member 22 and the part that provides the sealing between the flange 34 and the panel P, but in the push button switch 10, both are a single part, so production management based on materials is not complicated.

[0037] The flange 34 and the tubular member 22 are fixed together by a plurality of protruding pieces 36, and it is desirable to have a large number of protruding pieces 36 in order to securely fix the two together. On the other hand, if there are too many protruding pieces 36, the number of corresponding holes 52 also increases, reducing the remaining area of ​​the side surface portion 50. If the side surface portion 50 becomes smaller, the connection strength between the first annular portion 44 and the second annular portion 46 weakens, raising the concern that the second annular portion 46 may fall off. For this reason, the appropriate number of protruding pieces 36 and the holes 52 corresponding to the protruding pieces 36 is 6 to 8.

[0038] The present invention is not limited to the above-described embodiment, and can of course be freely modified within the scope of the gist of the present invention. [Explanation of symbols]

[0039] 10 Pushbutton switch 12 Control section 14 Contact point 16 frames 18 push rod 20 Controls 22 Cylindrical member 24 Gasket 28 Nut 30 Torso 32 Threaded part 34 flange 36 Projecting piece 36a 1st engagement protrusion 38 Outer wall 38b 2nd engagement protrusion 40 Inner wall 42 Inner edge 44 First Circular Ring 46 Second Circular Ring 48 Movable relay unit 50 Side part 52 Hole P Panel Pa mounting hole

Claims

1. a push rod inserted into a mounting hole in the panel and protruding to the rear side of the panel; an operator that is manually pressed to push out the push rod; a cylindrical frame inserted into the mounting hole and disposed on the outer circumferential side of the push rod; a threaded portion formed on an outer peripheral surface of the frame; a contact portion provided on the rear side of the panel, the connection state of the contact being switched in conjunction with the operation of the push rod; a nut that is screwed onto the threaded portion from the rear side of the panel and abuts against the rear surface of the panel; a flange protruding from the frame toward the outer periphery on the front side of the panel; a plurality of protruding pieces protruding radially from the outer peripheral end surface of the flange; a cylindrical member provided on the front side of the panel, the cylindrical member having an outer peripheral wall that engages with the plurality of protruding pieces and an inner peripheral wall that protrudes toward the surface of the panel; an annular packing made of an elastic material; and The packing is an inner peripheral end portion that abuts against the outer peripheral surface of the push rod to form a seal; a first annular portion having a front surface pressed by the inner circumferential wall, and a back surface abutting against a front surface of the flange to form a seal; a movable relay portion that connects the inner circumferential end portion and the first annular portion and is deformable in response to displacement of the push rod; a second annular portion that is sandwiched between the panel and the flange by the nut being threaded onto the threaded portion, thereby sealing the gap between the panel and the flange; a side surface portion connecting the first annular portion and the second annular portion on an outer circumferential side; a plurality of holes formed in the side surface and through which the protruding pieces are inserted; Equipped with A push button switch characterized by:

2. The protruding piece includes a first engagement projection that protrudes outward from a portion of the outer peripheral end surface near the front, the outer peripheral wall is provided with a second engagement projection that projects inward from a portion closer to the panel, The cylindrical member is fixed to the flange by the engagement of the first engaging projection and the second engaging projection.

2. The push button switch according to claim 1.

3. The number of the protruding pieces and the holes corresponding to the protruding pieces is 6 to 8.

2. The push button switch according to claim 1.

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