JP4279794B2 - Fluid pressure cylinder sensor fixture - Google Patents

Description

  The present invention relates to a sensor attachment for attaching a position detection sensor to a fluid pressure cylinder.

Conventionally, a position detection sensor for detecting the position of a piston provided in a cylinder tube is attached to a fluid pressure cylinder such as an air cylinder. In the case of a fluid pressure cylinder having a tie rod, the position detection sensor is attached to the outer periphery of the cylinder tube by attaching a dedicated sensor attachment to the tie rod. Such a sensor fixture is disclosed in Patent Document 1, for example. The sensor mounting tool of Patent Document 1 has a tie rod mounting groove that surrounds the outer periphery of a tie rod, and is configured to be mounted by tightening a mounting screw with the tie rod inserted into the tie rod mounting groove.
Japanese Patent Laid-Open No. 11-37112

  By the way, the sensor fixture of Patent Document 1 is configured to be able to slide the sensor fixture along the axial direction of the tie rod in a state where the tie rod is inserted into the tie rod mounting groove when the mounting screw is not tightened. Has been. For this reason, the sensor fixture of patent document 1 can adjust the attachment position of a position detection sensor by sliding a sensor fixture in the state which inserted the tie rod in the tie rod attachment groove | channel.

  However, the position adjustment can be performed relatively easily when the installation position of the fluid pressure cylinder is in the horizontal position (tilted state), but the position can be adjusted when the installation position is in the diagonal position or vertical position (in the standing state). There is a possibility that the workability of the adjustment is extremely lowered. That is, when the fluid pressure cylinder is placed at an angle or vertically, the sensor mounting tool will fall spontaneously through the tie rod. Therefore, the sensor mounting tool must always be held down by the operator's fingertip during position adjustment. At this time, if the mounting screw is tightened and the sensor fixture is temporarily fixed to the tie rod, the possibility of natural fall is reduced, but the mounting screw tightening force is adjusted so that the position can be adjusted when temporarily fixing. (It is necessary to adjust the force so that it can move in a tightened state without falling naturally), and workability is reduced.

  The present invention has been made paying attention to such problems existing in the prior art, and an object of the present invention is to provide a fluid pressure cylinder sensor attachment that can easily attach a position detection sensor. It is in.

According to the first aspect of the present invention, the position detection sensor for detecting the position of the piston accommodated in the cylinder tube of the fluid pressure cylinder is a sensor mounting member comprising a round bar or a square bar arranged around the cylinder tube. A sensor mounting tool for mounting by using a temporary fixing part for sandwiching the sensor mounting member in the mounting tool body and temporarily fixing the mounting tool body to the outer periphery of the sensor mounting member by an elastic force; A fixing portion is provided that presses the sensor mounting member sandwiched between the temporary fixing portions to fix the mounting body to the outer periphery of the sensor mounting member, and the mounting body includes a fixing piece, an elastic piece, A pressure receiving piece is integrally formed, and the fixed piece and the elastic piece are arranged to face the pressure receiving piece, and the sensor mounting member is disposed between the fixed piece and the pressure receiving piece and between the elastic piece and the pressure receiving piece. of An insertion portion is formed, and the temporary fixing portion is composed of the elastic piece and the pressure receiving piece, and is elastic when the elastic piece comes into contact with the sensor mounting member sandwiched between the elastic piece and the pressure receiving piece. The fixing portion includes the fixing piece and the pressure receiving piece, and a screw hole that opens toward the insertion portion is formed in the fixing piece, and the fixing screw is screwed into the screw hole. The gist is to press the sensor mounting member against the pressure receiving piece .

The gist of the invention described in claim 2 is that, in the invention described in claim 1 , the pressure-receiving piece is formed to be bent in a direction orthogonal to the press-contact direction.
According to a third aspect of the present invention, in the first or second aspect of the present invention, a reinforcing rib extends along the pressure-contact direction in the fixture body so as to include a bent portion of the fixing piece. The gist is that it is provided.

The invention according to claim 4 is the invention according to any one of claims 1 to 3 , wherein the fixture body is configured separately from the fixture body, and the position detection sensor. The gist is that the sensor holder to which is attached is attached.

The invention according to claim 5 is the invention according to any one of claims 1 to 4 , wherein the sensor mounting member is a tie rod that is assembled to a cover member that closes the cylinder tube. The gist.

  According to the present invention, the position detection sensor can be easily attached to the fluid pressure cylinder.

Hereinafter, an embodiment in which the sensor mounting bracket of the present invention is embodied will be described with reference to FIGS.
As shown in FIG. 1, an air cylinder 10 as a fluid pressure cylinder includes a cylindrical cylinder tube 11, and both side openings in the axial direction are a head cover (cover member) 12 and a rod cover (cover member) 13. It is blocked by The head cover 12 and the rod cover 13 are integrally assembled by tie rods 14 and nuts 15 as a plurality (four in this embodiment) of sensor mounting members. In the present embodiment, the four tie rods 14 are formed in a columnar shape (round bar). A piston (not shown) that is movable along the axial direction of the cylinder tube 11 by fluid pressure (air in the present embodiment) is accommodated in the internal space of the cylinder tube 11. The piston is integrally provided with a rod 16 penetrating and supported by the rod cover 13, and the rod 16 is projected and retracted as the piston moves.

  A position detection sensor 17 that detects the position of a piston that reciprocates in the cylinder tube 11 is attached to the outer periphery of the cylinder tube 11. The position detection sensor 17 is an MR sensor that detects the position of the piston by magnetic resistance. The position detection sensor 17 is attached to the outer periphery of the cylinder tube 11 using a sensor attachment 18. The sensor attachment 18 is attached to the tie rod 14, and the attachment position is adjusted and fixed so that the position of the position detection sensor 17 is a desired position (position where the piston can be detected) in the axial direction of the tie rod 14. .

  Hereinafter, the sensor fixture 18 of the present embodiment will be described in detail with reference to FIGS. In the following description, “upper”, “lower”, “left”, “right”, “front”, and “rear” are obtained when the sensor fixture 18 is viewed from the direction of arrow A shown in FIG. 2 (as shown in FIG. 3A). "Upper", "Lower", "Left", "Right", "Front", and "Rear" in the case where the sensor fixture 18 is viewed from the front.

  The sensor fixture 18 includes a fixture body 19 and a sensor holder 20. The sensor holder 20 is formed in a concave section having a sensor mounting groove 21, and the position detection sensor 17 is mounted (accommodated) in the sensor mounting groove 21. The sensor holder 20 is configured separately from the fixture body 19. In the present embodiment, the sensor holder 20 is fixed to the fixture body 19 by welding.

  The fixture body 19 is made of a metal plate (SUS304CSP (stainless steel strip for springs) in the present embodiment), and is provided with a fixing piece 23 bent in a predetermined direction, an elastic piece 24, and a pressure receiving piece 25. ing. The fixture body 19 includes the fixed piece 23, the elastic piece 24, and the pressure receiving piece 25, and is integrally formed by pressing. The fixing piece 23 is provided on the front end side of the fixture main body 19 and is bent toward the lower side of the sensor fixture 18 (the fixture main body 19). Further, a screw hole 26 is formed through the fixed piece 23. The screw hole 26 is penetrated along the front-rear direction of the fixture main body 19, and the attachment screw 27 is screwed therein. When the sensor fixture 18 is attached to the tie rod 14, the tie rod 14 is pressed by the screwing of the mounting screw 27, and the screwing direction of the mounting screw 27 becomes the pressing direction.

  A pair of elastic pieces 24 are provided on the front end side of the fixture main body 19 and on the left and right sides of the fixed piece 23 in the same direction as the fixed piece 23, that is, below the sensor fixture 18 (the fixture main body 19). It is bent toward the front. The elastic piece 24 is formed at a predetermined interval in the left-right direction of the fixture body 19 with respect to the fixed piece 23. That is, the pair of elastic pieces 24 are formed in a state separated from the fixed piece 23. In addition, the elastic piece 24 is formed such that its lateral width is narrower than the lateral width of the fixed piece 23. More specifically, the elastic piece 24 is formed with a reduced width in the left-right direction so as to reduce rigidity and have an elastic force. Further, the elastic piece 24 is bent so that its tip end is inclined forward.

  In addition, a pair of pressure receiving pieces 25 are formed to be bent toward the lower side of the sensor attachment 18 on the left and right ends of the attachment body 19 and behind each elastic piece 24. The pressure receiving piece 25 is bent in a direction orthogonal to the bending direction of the fixed piece 23 and the elastic piece 24. More specifically, the pressure receiving piece 25 is formed to be bent in a direction perpendicular to the press contact direction by the screwing of the mounting screw 27. Each pressure receiving piece 25 is formed at a predetermined interval in the front-rear direction of the fixture body 19 with respect to the fixed piece 23 and each elastic piece 24. The pressure receiving piece 25 is disposed so as to face the fixed piece 23 and the elastic piece 24. Further, the pressure receiving piece 25 is formed in a sharp shape toward the tip thereof, and the pressure receiving surface 25a facing the elastic piece 24 is bent and formed in a “<” shape in a side view (FIG. 3B). .

  In addition, a plurality of (three in this embodiment) reinforcing ribs 28 are formed in the fixture body 19 along the front-rear direction. Of the three reinforcing ribs 28, the two reinforcing ribs 28 extend straight from the front end (lower end) of the fixed piece 23 along the front-rear direction. The remaining one reinforcing rib 28 extends straight from the upper part of the screw hole 26 formed in the fixing piece 23 along the front-rear direction. That is, the three reinforcing ribs 28 are formed on the fixture main body 19 so as to include the bent portion of the fixing piece 23. The reinforcing rib 28 increases the thickness of the bent portion of the fixing piece 23 and increases the rigidity in the bending direction. The reinforcing rib 28 is integrally formed together with the fixed piece 23, the elastic piece 24, and the pressure receiving piece 25 by pressing. The sensor attachment 18 shown in FIG. 1 is illustrated with the reinforcing rib 28 omitted.

  The sensor fixture 18 of the present embodiment has the pieces 23, 24, 25 so that the insertion portion 29 of the tie rod 14 is between the fixed piece 23 and the pressure receiving piece 25 and between the elastic piece 24 and the pressure receiving piece 25. Is formed. Moreover, the opening part 30 between the elastic piece 24 and the pressure receiving piece 25 is comprised as an insertion port into which the tie rod 14 is inserted. The elastic piece 24 and the pressure receiving piece 25 (pressure receiving surface 25 a) are in contact with the outer periphery of the tie rod 14 inserted from the opening part 30, and the tie rod 14 is sandwiched between both pieces 24 and 25. Thereby, the elastic force from the elastic piece 24 acts on the tie rod 14 and is held by the insertion portion 29. Further, the opening portion 30 is widened by bending of the distal end portion of the elastic piece 24. Further, the pressure receiving surface 25 a of the pressure receiving piece 25 has a bent shape along the outer periphery of the tie rod 14. In the present embodiment, the elastic piece 24 and the pressure receiving piece 25 function as a temporary fixing portion that temporarily fixes the sensor attachment 18 to the tie rod 14.

  When the tie rod 14 is inserted into the insertion portion 29, the tie rod 14 is also disposed between the fixed piece 23 and the pressure receiving piece 25. The fixing piece 23 is formed with a screw hole 26 toward the insertion portion 29, and the mounting screw 27 is screwed into the insertion portion 29. For this reason, the mounting screw 27 screwed into the screw hole 26 abuts on and presses the outer periphery of the tie rod 14 disposed in the insertion portion 29. This pressing force is received by the pressure receiving piece 25 disposed facing the fixed piece 23 as a wall. As a result, the tie rod 14 is pressed between the mounting screw 27 screwed into the fixed piece 23 and the pressure receiving piece 25. In the present embodiment, the fixing piece 23 (attachment screw 27) and the pressure receiving piece 25 function as a fixing portion that fixes the sensor attachment 18 to the tie rod 14.

Hereinafter, a method for attaching the position detection sensor 17 using the sensor attachment 18 of the present embodiment will be described.
First, the position detection sensor 17 is mounted on the sensor mounting groove 21 of the sensor holder 20, and the position detection sensor 17 is mounted on the sensor fixture 18. The position detection sensor 17 is fixed to the sensor mounting groove 21 with screws. Then, the sensor fixture 18 to which the position detection sensor 17 is attached is temporarily fixed to the tie rod 14. In order to temporarily fix the sensor attachment 18, the fingertip is picked and positioned so that the opening portion 30 faces the tie rod 14. Then, the opening portion 30 is applied to the outer peripheral surface of the tie rod 14, and the sensor attachment 18 is pressed against the tie rod 14 so as to push the tie rod 14 into the insertion portion 29. The sensor fixture 18 is pushed in along the radial direction of the tie rod 14. At this time, the elastic piece 24 of the sensor fixture 18 is elastically deformed so as to widen the opening portion 30 when a pressing force is applied. As a result, the tie rod 14 passes through the opening portion 30 and is inserted into the insertion portion 29. The tie rod 14 inserted into the insertion portion 29 is held in the insertion portion 29 by the elastic force from the elastic piece 24. In this state, the sensor fixture 18 is temporarily fixed to the outer periphery of the tie rod 14. In addition, the position at which the sensor fixture 18 is temporarily fixed may be any position in the axial direction of the tie rod 14.

  Next, the position at which the sensor fixture 18 to which the position detection sensor 17 is attached is fixed to the tie rod 14, that is, the position at which the position detection sensor 17 is attached to the cylinder tube 11 is adjusted. This position adjustment is an adjustment performed so that the position detection sensor 17 can detect the position of the piston accommodated in the cylinder tube 11. The position adjustment is performed while moving the sensor fixture 18 in the temporarily fixed state along the axial direction of the tie rod 14. That is, since the sensor attachment 18 is attached to the tie rod 14 only by the elastic force of the elastic piece 24 in the temporarily fixed state, the force of the tie rod 14 is not removed from the tie rod 14 by applying a force along the axial direction. It is movable along the axial direction. When the sensor fixture 18 is moved, the position detection sensor 17 attached to the sensor fixture 18 (sensor holder 20) is also moved together.

  Then, after the adjustment of the position for fixing the sensor attachment 18 is completed, the sensor attachment 18 is fixed at the adjusted position. The sensor fixture 18 is fixed by screwing a mounting screw 27 into the screw hole 26 of the fixing piece 23. When the mounting screw 27 is screwed, the tip of the mounting screw 27 comes into contact with the outer periphery of the tie rod 14 in the insertion portion 29. As a result, the tie rod 14 is brought into pressure contact with the attachment screw 27 and the pressure receiving piece 25, and the sensor attachment 18 is fixed to the tie rod 14. Further, by fixing the sensor mounting tool 18, the position detection sensor 17 is mounted at a desired position (position after adjustment). When the position of the position detection sensor 17 needs to be finely adjusted after the sensor fixture 18 is fixed, the screw for fixing the position detection sensor 17 to the sensor mounting groove 21 is once loosened, and the position detection sensor 17 is moved to the sensor. It is adjusted by sliding in the mounting groove 21. Thereafter, the position detection sensor 17 is fixed to the sensor mounting groove 21 with screws.

  Incidentally, when detaching (removing) the sensor attachment 18 from the tie rod 14, first, the attachment screw 27 is loosened to release the fixed state. Next, the sensor fixture 18 is pulled out along the radial direction of the tie rod 14. At this time, the elastic piece 24 of the sensor fixture 18 is elastically deformed so as to widen the opening portion 30 by the force of pulling out. As a result, the sensor fixture 18 is detached from the tie rod 14.

Therefore, according to the present embodiment, the following effects can be obtained.
(1) The fixture main body 19 of the sensor fixture 18 is provided with a temporary fixing portion including the elastic piece 24 and the pressure receiving piece 25 and a fixing portion including the fixing piece 23 and the pressure receiving piece 25. With this configuration, the sensor fixture 18 can be temporarily attached to the outer periphery of the tie rod 14 by the elastic force of the elastic piece 24. For this reason, at the time of position adjustment, regardless of the installation posture of the air cylinder 10, the sensor fixture 18 is held on the outer periphery of the tie rod 14 by temporary fixing, and the workability of the adjustment work is improved. Therefore, the position detection sensor 17 (sensor attachment 18) can be easily attached to the air cylinder 10. In addition, after the position adjustment, the tie rod is pressed by the fixing piece 23 and the pressure receiving piece 25, so that the position detection sensor 17 (sensor mounting tool 18) can be reliably fixed to the air cylinder 10 as before.

  (2) The fixing piece 23, the elastic piece 24, and the pressure receiving piece 25 are integrally formed on the fixture body 19. For this reason, it is possible to provide the sensor fixture 18 having a strength capable of withstanding the pressing force at the time of fixing while giving an elastic force for temporary fixing. Moreover, since the fixture main body 19 is formed by pressing from a single metal plate, it is possible to contribute to reducing the manufacturing cost of the sensor fixture 18.

  (3) The pressure receiving piece 25 was formed by being bent in a direction orthogonal to the pressure contact direction. For this reason, at the time of fixation, it can prevent that the receiving pressure piece 25 bends in the press-contact direction by press-contact force (a deformation | transformation of the fixture main body 18 can be prevented). That is, the strength of the pressure receiving piece 25 can be increased, and the sensor fixture 18 can be reliably fixed to the tie rod 14.

  (4) Reinforcing ribs 28 are extended along the pressure-contact direction on the fixture body 19 so as to include the bent portion of the fixing piece 23. For this reason, at the time of fixation, it can prevent that the fixing piece 23 receives a press-contact force and bends (a deformation | transformation of the fixture main body 18 can be prevented).

  (5) The fixture body 19 and the sensor holder 20 are configured separately. When the fixture main body 19 and the sensor holder 20 are integrally configured, it is necessary to manufacture the sensor fixture 18 for each size of the position detection sensor 17, leading to an increase in manufacturing cost. For this reason, by making the fixture main body 19 and the sensor holder 20 separate, even if the size of the position detection sensor 17 is different, it is only necessary to prepare the sensor holder 20 suitable for the size. Can be treated as a common part.

In addition, you may change this embodiment as follows.
-In embodiment, you may change the shape of the elastic piece 24 as shown in FIG.4 and FIG.5. The elastic piece 24 shown in FIGS. 4 and 5 is formed in a wave shape. That is, the elastic piece 24 is formed so that the contact surface thereof follows the outer peripheral surface shape of the tie rod 14 when the tie rod 14 is inserted into the insertion portion 29.

In the embodiment, the fixture main body 19 and the sensor holder 20 may be integrally formed.
In the embodiment, the timing for mounting the position detection sensor 17 on the sensor holder 20 may be changed. For example, the position detection sensor 17 may be attached to the sensor holder 20 during temporary fixing.

  -In embodiment, the fixture main body 19 and the sensor holder 20 which were made into the separate structure may be shape | molded with the same material, and may be shape | molded with a different material. When molding with a different material, it is desirable to use a non-magnetic material for the sensor holder 20 in order to suppress the influence on the position detection sensor 17 that detects the magnetic resistance.

  -In embodiment, you may comprise the fixture main body 19 by phosphor bronze etc., for example. That is, the fixture body 19 is preferably made of a material that is excellent in corrosion resistance in consideration of the installation environment of the air cylinder 10 and has a weak magnetic force in consideration of the influence on the position detection sensor 17 that detects the magnetic resistance.

In the embodiment, the number of screw holes 26 formed in the fixing piece 23 may be changed to, for example, two or three.
In the embodiment, the arrangement of the fixed piece 23 and the elastic piece 24 may be reversed. That is, the elastic piece 24 may be formed in the center and the fixing pieces 23 may be provided on both sides thereof.

  In the embodiment, the attachment member of the sensor attachment 18 is embodied in the tie rod 14, but it may be attached to another member. For example, a member made of a round bar or a square bar is provided separately from the tie rod 14 so as to be arranged around the cylinder tube 11 (near the outer peripheral surface), and a sensor fixture 18 is attached to the member to attach the position detection sensor 17 to the cylinder. You may attach to the outer periphery of the tube 11. FIG. If such a member is used, the position detection sensor 17 can be attached irrespective of the presence or absence of the tie rod 14.

  In the embodiment, the elastic piece 24 is integrally formed with the fixture main body 19, but an elastic force may be applied by another member instead of the elastic piece 24. For example, a spring member such as a leaf spring may be fixed to the fixture main body 19 by welding or caulking, and the tie rod 14 may be sandwiched between the spring member and the pressure receiving piece 25 to apply an elastic force.

Next, a technical idea that can be grasped from the above embodiment and another example will be added below.
(B) A temporary fixing portion that clamps the tie rod of the fluid pressure cylinder to the fixture main body and temporarily fixes the fixture main body to the outer periphery of the tie rod by an elastic force, and press-contacts the tie rod sandwiched between the temporary fixing portions. In this mounting method, a position detection sensor for detecting the position of the piston of the fluid pressure cylinder is attached to the fluid pressure cylinder using a sensor attachment tool provided with a fixing portion for fixing the attachment body to the outer periphery of the tie rod. A step of sandwiching the tie rod in the temporary fixing portion and temporarily fixing the sensor fixture to the outer periphery of the tie rod; and a sensor fixture in which the position detection sensor is mounted in a state where the sensor fixture is temporarily fixed. Adjusting the position where the sensor fixture is fixed by moving it in the axial direction of the tie rod; and after adjusting the fixing position, Mounting of the position detection sensor pressed against the tie rod, characterized in that a step of fixing the sensor fitting on the outer periphery of the tie rod.

The perspective view of an air cylinder. The perspective view of a sensor fixture. (A) is a front view of a sensor fixture, (b) is a side view of a sensor fixture. The perspective view of the sensor fixture of another example. (A) is a front view of another example of a sensor fixture, (b) is a side view of another example of a sensor fixture.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Air cylinder (fluid pressure cylinder), 11 ... Cylinder tube, 12 ... Head cover (cover member), 13 ... Rod cover (cover member), 14 ... Tie rod (sensor attachment member), 17 ... Position detection sensor, 18 ... Sensor Attaching tool, 19 ... mounting tool body, 20 ... sensor holder, 23 ... fixing piece (fixing part), 24 ... elastic piece (temporary fixing part), 25 ... pressure receiving piece (fixing part, temporarily fixing part), 26 ... screw hole , 27 ... mounting screws, 28 ... reinforcing ribs, 29 ... insertion part.

Claims (5)

A sensor mounting tool for mounting a position detection sensor for detecting the position of a piston accommodated in a cylinder tube of a fluid pressure cylinder to a sensor mounting member made of a round bar or a square bar arranged around the cylinder tube,
The sensor mounting member is clamped between the sensor mounting member and the sensor mounting member clamped to the outer periphery of the sensor mounting member by an elastic force, and the sensor mounting member sandwiched between the temporary mounting portion is pressed against the mounting body. A fixing portion for fixing the mounting body to the outer periphery of the sensor mounting member ,
A fixing piece, an elastic piece, and a pressure receiving piece are integrally formed on the fixture main body, and the fixing piece and the elastic piece are disposed opposite to the pressure receiving piece, and between the fixing piece and the pressure receiving piece. An insertion portion of the sensor mounting member is formed between the elastic piece and the pressure receiving piece,
The temporary fixing portion includes the elastic piece and the pressure receiving piece, and applies an elastic force when the elastic piece abuts on the sensor mounting member sandwiched between the elastic piece and the pressure receiving piece.
The fixing portion includes the fixing piece and the pressure receiving piece, and a screw hole that opens toward the insertion portion is formed in the fixing piece, and the sensor attachment member is inserted into the screw hole by an attachment screw. A pressure sensor is attached to the pressure receiving piece . The sensor mounting tool for a fluid pressure cylinder according to claim 1, wherein the pressure receiving piece is bent in a direction orthogonal to the pressure contact direction . The fluid pressure cylinder according to claim 1 or 2, wherein a reinforcing rib is extended along the pressure-contact direction so as to include a bent portion of the fixing piece in the fixture body. Sensor fittings. The said fitting body, is a separate structure and with tool body said mounting any one of claims 1 to claim 3, characterized in that the sensor holder for mounting the position detecting sensor is attached The sensor mounting tool of the fluid pressure cylinder as described in 2. The said sensor attachment member is a tie rod assembled | attached to the cover member which obstruct | occludes the said cylinder tube, The sensor attachment tool of the fluid pressure cylinder as described in any one of Claims 1-4 characterized by the above-mentioned .

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