JP3647371B2 - Power take-off valve operating device and mounting method thereof - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a power take-off valve operating device and a mounting method thereof.
[0002]
[Prior art]
Conventionally, in a construction machine such as a crane, a vehicle, or various industrial machines, a power take-off valve (hereinafter referred to as a PTO valve) is used to extract the power of the engine. The PTO valve is operated by an operating device using a push-pull control cable for remote control from a cab or the like. This can switch the PTO valve via a cable by pushing and pulling the knob.
[0003]
In such a conventional power take-off valve operating device (hereinafter referred to as a PTO operating device), a limit switch for detecting the position of the knob or operating rod is attached in order to notify a forgotten return of the knob with a warning lamp or the like. For example, the PTO operation device shown in FIG. 6 includes a holder 102 for attaching a push-pull control cable to the operation panel 101 and the like, and an operation rod 103 that slides in the holder 102 to push and pull the inner cable. Screwed to the operation panel 101 together with a bracket 105 for mounting the switch 104. A disc-like contact member 107 is attached to the operating rod 103 to contact the operating portion 106 of the limit switch 104.
[0004]
Such a PTO operation device can attach the push-pull control cable and the bracket 105 with the holder 102 and then attach the limit switch 104, the electrical components including the lead wire and the connector, and is sufficient even in a bad environment such as vibration. However, there is a problem that parts such as the bracket 105 and the abutting member 107 protrude greatly and become bulky.
On the other hand, in choke operation devices such as passenger cars, the operation force of the choke valve may be small, and the choke valve biased in the opening direction by a spring is operated by a pull control cable, and they are fixed in them. A contact and a movable contact integrated into the holder (see Japanese Utility Model Publication Nos. 51-26811 and 58-161150), or a permanent magnet provided on the operating rod, and a reed switch built in the holder. Have been proposed (see Japanese Utility Model Publication No. 52-93827).
[0005]
However, there is no problem with a light pull control cable, but with a relatively heavy push-pull control cable, the mechanical parts and electrical parts may not be separated, which can lead to switch failure during assembly. And reliability is not sufficient. Therefore, the configuration of these built-in switches cannot be directly used for the PTO operation device.
[0006]
[Problems to be solved by the invention]
An object of the present invention is to provide a PTO operating device that can be retrofitted with an electrical component and is configured in a compact manner, and to provide a method for attaching the PTO operating device.
[0007]
[Means for Solving the Problems]
The power take-off valve operating device (Claim 1) of the present invention has a flexible conduit having one end connected to a fixing member on the power take-off valve side, and is slidably inserted into the conduit, and one end is powered. A push-pull-operated inner line connected to the actuating member of the take-off valve, a rod connected to the other end of the inner line and having a handle at the free end, and the other end of the conduit are connected to A cylindrical holder that is slidably guided in a direction, and a switch storage box that is detachably provided so as to protrude radially from the holder. The holder communicates with the inside of the holder and the switch storage box. An opening is formed, and a warning lamp for detecting the position of the rod through the opening and displaying the operating state of the power take-off valve is lit on the switch storage box. Are limit switches accommodated to the which the engaging stepped portion is formed on an outer periphery of the holder, with the left and right walls facing the holder on top of the switch housing box is provided, the engagement on the upper end of their walls A locking claw that is elastically engaged with the stepped portion is provided . The limit switch mentioned here includes a so-called micro switch provided with a spring return actuator, and a micro switch.
[0008]
In such a power take-off valve operating device, it is preferable that the opening is a window through which the operating piece of the limit switch passes, and the operating piece is arranged so as to detect the end of the rod. . The opening may be a slit extending in the axial direction, and the rod may be provided with a protrusion that enters the slit. Further, the holder includes a thin-walled cylindrical conduit mounting portion, a guide hole for guiding the rod so as to be slidable in the axial direction, and a wall portion interposed between the conduit mounting portion and the guide hole. In addition, it is preferable that a small hole is formed for passing an inner cord communicating with the guide hole and the conduit mounting portion (claim 4) .
[0009]
In the power take-off valve operating device described above, one end of the conduit is further fixed to a holder on the power take-off valve side (operation side), and the holder is attached to the fixing member so that the position in the axial direction can be adjusted. (Claim 5 ). The method for attaching the power take-off valve operating device according to the present invention (Claim 6 ) is a method for assembling such a device, and the conduit is caulked to the holder on the operating side and the holder on the power take-off valve side (the operating side). Both holders are attached to the mating member, the mounting position of the holder on the power take-off valve side is adjusted based on the operating range of the rod, and then the switch storage box containing the limit switch is attached to the holder.
[0010]
[Action]
In the power take-off valve operating device of the present invention, the terminal in the limit switch is turned on and off through an opening that communicates the position of the rod with the holder body and the switch storage box. For example, when the limit switch detects that the power take-off valve that pushes the handle is OFF, turn off the warning lamp, pull the handle and pull out the rod, the limit switch detects and the warning lamp lights up Let As described above, in the power take-off valve operating device of the present invention, the limit switch directly detects the position of the rod, so that there is no need for a disc-shaped contact plate or bracket as in the conventional PTO operating device, and the whole is extremely It can be configured compactly. Further, since the switch storage box is detachable from the holder, the switch storage box storing the limit switch can be mounted after the mechanical parts are mounted. Therefore, handling of mechanical parts is easy and not bulky, and electric parts such as limit switches are less damaged. In addition, a reliable general-purpose product can be used.
Further, an engagement step is formed on the outer periphery of the holder, and left and right walls holding the holder are provided at the upper part of the switch storage box, and the engagement step is elastically engaged with the upper end of these walls. Since the engaging claw is provided, the engaging claw is elastically engaged with the engaging step portion only by pressing the switch storage box against the holder in the radial direction. Therefore, the limit switch can be attached later more easily and can be easily replaced. Further, if the limit switch is attached with two screws penetrating the switch storage box, it can be stably and surely attached even if there is a gap between the limit switch and the side wall.
[0011]
When the opening is a window through which the operating piece of the limit switch passes, and the operating piece is arranged so as to detect the end of the rod (Claim 2), The tip of the protruding operating piece is in contact with the outer periphery of the rod. When the handle is pulled to operate the PTO valve, the rod slides in the holder, and the tip of the limit switch operating piece moves away from the rod. The operating state of the power take-off valve can be detected by such movement of the operating piece. Said opening is a slit bets axially extending, the device protrusions entering slits in the rod is provided (claim 3), to detect the position of a projection which moves with the movement of the rod limit switch it can. At that time, the holder body guides the rod in the axial direction, and the protrusion moves in the slit, so that the rotation around the axis is restricted and the inner cable is not easily kinked. The width of the slit is preferably smaller than the diameter of the inner line so that when a compressive force is applied to the inner line, the slit does not enter the slit. The holder includes a thin-walled cylindrical conduit mounting portion, a guide hole that guides the rod in an axially slidable manner, and a wall portion interposed between the conduit mounting portion and the guide hole. In the power take-off valve operating device (Claim 4), in which a small hole is formed for passing an inner line communicating with the guide hole and the conduit mounting portion, the conduit for supporting the reaction force of the inner line for pushing and pulling is firmly secured. And can hold. In addition, buckling is unlikely to occur in the inner cable.
[0013]
In the case where the holder on the power take-off valve side of the conduit is provided on the fixing member so that the position thereof can be adjusted (Claim 5) , the position of the holder relative to the fixing member can be adjusted in accordance with the operation range of the rod. Therefore, the operating range of the rod can be adjusted appropriately. According to the power take-off valve mounting method of the present invention (Claim 6) , since the switch storage box is inserted after the mechanical parts are assembled and adjusted, there is little damage to electrical parts such as limit switches. In addition, a reliable general-purpose product can be used.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment of a power take-off valve operating device of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional side view of an essential part before assembly showing an embodiment of an operation side of a PTO operating device of the present invention, FIG. 2a is a partially cutaway perspective view of a holder in FIG. 1, and FIG. 3a and 3b are sectional views showing the assembled state and the operating state of the PTO operating device of FIG. 1, respectively, and FIG. 4 is a partially sectional side view showing the whole embodiment of the PTO operating device of the present invention. FIG. 5 is a cross-sectional view of the main part showing the operation side of another embodiment of the PTO operation device of the present invention.
[0015]
FIG. 1 shows the operating side A of the PTO operating device shown in FIG . This operation side A (control cable with switch) is a mechanical part composed of a holder 1, a rod 2 and a push-pull control cable (hereinafter referred to as control cable) 3, and an electrical part composed of a microswitch 5, a lead wire 6 and a connector 7. It is divided into and. The control cable 3 is a known cable comprising a conduit 8 and an inner cable 9 that slides in the conduit 8 and transmits a pulling force. Further, the microswitch 5 is housed in a switch housing box 11.
[0016]
The front end of the holder 1 is a thin cylindrical conduit mounting portion 12 for caulking and fixing the conduit 8, and a nut 13 for mounting the holder 1 to a counterpart member such as the operation panel P is provided on the outer periphery of the rear end. And the screw 15 for the end nut 14 is cut. A wall portion 16 is provided near the tip of the holder 1 so as to block the axis, and a small hole 17 through which the inner cable 9 is passed is formed in the wall portion 16. Further, a guide hole 18 for guiding the rod 2 in an axially slidable manner is formed on the front side of the wall portion 16. The guide hole 18 and the inside of the switch storage box 11 are separated by a bottom wall 18a, and a rectangular window 19 is opened in the bottom wall 18a. Further, as shown in FIGS. 2a and 2b, a pair of left and right concave grooves 20 are formed so as to extend in the axial direction on the outer periphery of the holder 1 at a substantially central portion in the up-down direction or at a somewhat upper side. A rectangular locking recess 21 is formed on the lower side of the front portion. The recessed groove 20 and the locking recess 21 are locking steps in claim 5.
The rod 2 is, for example, a rod having a circular cross section or a hexagonal cross section, and an inner cable 9 is embedded and connected to the tip thereof. That is, the diameter of the rod 2 is larger than the inner cable.
[0017]
2a and 2b, the switch storage box 11 includes two rectangular side walls 22 and 23 extending in the axial direction and an end wall 24 that closes the front end, and is made of an elastic material such as synthetic resin. It is made of a material having properties. An upper end side of the switch storage box 11 is opened to hold the holder 1, and a rear end side is opened to allow the lead wire 6 to pass. A pair of first locking claws 25 that elastically engage with the concave groove 20 of the holder 1 protrudes on the inner side of the upper ends of the side walls 22 and 23. The first locking claw 25 extends in the axial direction. Further, in the vicinity of the end wall 24, a second locking claw 26 that is elastically engaged with the locking recess 21 of the holder 1 is formed. The end wall 24 is formed with a contour corresponding to the outer shape of the holder 1, for example, an arc-shaped cutout 27. The left and right side walls 22 and 23 are formed with holes 28a through which screws 28 for attaching the microswitch 5 are passed.
[0018]
Returning to FIG. 1, the end nut 14 screwed into the end of the holder 1 has an O-ring 29 that comes into sliding contact with the surface of the rod 2 and seals, and reference numeral 29 a is a toothed washer.
[0019]
The micro switch 5 is a commercially available one having, for example, a roller lever type operating piece 30, and a roller 31 is rotatably attached to the tip of the operating piece 30. Further, the microswitch 5 is attached to the connector 7 by its common terminal COM, normally open terminal NO, and normally closed terminal NC. The connector 7 is made of a synthetic resin such as polybutylene terephthalate (PBT) or polyphenylene sulfide (PPS), and internally includes terminal plates 33 and 34 connected to a normally open terminal NO (or normally closed terminal NC) and a common terminal COM. Embedded. The terminal plates 33 and 34 are connected to lead wires 6 a and 6 b that are exposed to the outside from the rear end side of the connector 7.
[0020]
In order to attach the operating side A, which is divided into mechanical parts and electrical parts as described above, to the mating member, the mechanical end is first attached to the mating member, and the stroke end and the mating device are operated while pushing and pulling the rod 2 The correspondence relationship with the operating range (for example, PTO valve) is adjusted. Next, the microswitch 5 and the connector 7 are stored in the switch storage box 11, and the upper opening of the switch storage box 11 is pressed against the holder 11. Then, the side walls 22 and 23 provided with the first locking claws 25 are bent outward, and the first locking claws 25 are elastically engaged in the recessed grooves 20. Thereby, the switch storage box 11 can be attached to the holder 1 as shown in FIGS. As described above, since the operation side A can assemble mechanical parts and electric parts separately, it can be adjusted and tested individually, which is convenient. Moreover, there is little risk of damaging electrical components during assembly.
[0021]
In the assembled state as described above, as shown in FIG. 3 a, the roller 31 of the operating piece 30 of the microswitch 5 enters the inside of the window 19. Therefore, the roller 31 comes into contact with the surface of the rod 2 that is pushed into the back of the guide hole 18 in a state where the operating piece 30 is pushed radially outward (in the direction of arrow B) against the urging force of the return spring. ing. Then, as shown in FIG. 3b, when the rod 2 is pulled out from the holder 1 (arrow C direction) and the inner cable 9 is pulled, the rod 2 is actuated when the end surface 38 comes to the left in the figure from the roller 31. The roller 31 returns to the inside in the radial direction (arrow D direction) by the restoring force of the piece 30 and enters the guide hole 18. As a result, the microswitch 5 is activated. On the contrary, when the rod 2 is pushed in the direction of arrow E from the state and the inner cable 9 is pushed, the roller 31 is pushed out in the direction of arrow B by the end face 38 of the rod 2 (see FIG. 3a). Whether the lead wires 6a and 6b are short-circuited or opened when the roller 31 comes inside can be selected by connecting the lead wire 6a to the normally closed terminal NC or the normally open terminal NO. it can. The other lead wire is connected to the common terminal COM.
[0022]
In the above operation, the rod 2 side is pushed and pulled, but as is apparent from FIGS. 3a and 3b, the other end side of the inner cable 9 is pushed and pulled to move the rod 2 in the same manner. The microswitch 5 can be switched. Further, as shown in FIG. 3a, a stepped portion 39 is formed on the rear end side of the holder 1 to abut against the switch storage box 11 and securely support them.
[0023]
Although the roller lever type micro switch 5 is employed as the limit switch in the embodiment, other types of limit switches such as a push-in micro switch may be employed. Further, the larger the difference between the radii of the rod 2 and the inner cable 9, that is, the step (y in FIG. 3b), is easier to detect by the limit switch, but the risk of buckling of the inner cable 9 increases. Therefore, although it depends on the diameter of the inner cable 9 and the stroke of the rod 2, the step is preferably about 2.0 to 3.0 mm.
[0024]
Next, an embodiment of the PTO operation device K to which the operation side A is applied will be described with reference to FIG. The operation side K1 of the apparatus K in FIG. 4 is the same as the operation side A in FIGS. 1 to 3 except that a hexagonal bar is used as the rod 2 and the handle 40 is attached to the free end thereof. The same reference numerals are given and description thereof is omitted. The operating side K2 of the device K is substantially the same as that of the conventional PTO operating device. That is, it has a cylindrical holder 43 in which mounting nuts 41, 42 to the fixing member P <b> 2 are screwed, and a conduit 8 is caulked to a conduit mounting portion 44 of the holder 43. A guide pipe 45 is swingably connected to the other end of the holder 43, and a rod 46 is slidably inserted into the guide pipe 45. An inner cable 9 is caulked to the proximal end side (left side of the drawing) of the rod 46, and a joint 47 connected to the PTO valve is screwed to the distal end side. Reference numeral 48 is a known bellows boot, and 49 is a grommet.
[0025]
In the PTO operation device K configured as described above, the operation-side handle 40 is always pushed in the direction of arrow E, and this is a state in which the PTO valve is being pushed. From this state, when the handle 40 is pulled in the direction of arrow C and the rod 2 is pulled out of the holder 1, the operating side rod 45 is pulled in the direction of arrow C2 via the inner cable 9, and the PTO valve is pulled. Thereby, the engine power is taken out from the vehicle to the equipment. At that time, the microswitch 5 is turned ON, a signal is sent to the safety device through the lead wire 6, and the warning lamp is turned on. This informs the driver that the PTO valve has been switched.
[0026]
Then, when the operation of the device is finished, the handle 40 is pushed in, and the operating side rod 46 is extended in the direction of arrow E2 through the inner cable 9. As a result, the PTO valve is switched, the contact a of the micro switch 5 is turned OFF, and the warning lamp is turned off. In the above PTO operation device K, (1) electrical related parts can be assembled after assembly adjustment of machine related parts, (2) the limit switch is highly reliable, and (3) failure during installation. The above-mentioned advantage of the operation side A such that there is little risk of the above is obtained as it is.
[0027]
On the operation side A1 of the PTO operation device shown in FIG. 5, a slit 51 is formed in the bottom wall 18a of the holder 1 so as to extend in the axial direction and open in the radial direction. The width of the slit 51 is smaller than the diameter of the inner cable 9, and is usually about 1/3 to 2/3. Further, a projecting piece 52 projects downward from the tip of the rod 2. The protruding piece 52 has a thin plate shape that slides in the slit 51. However, it may be pin-shaped. The tip of the protruding piece 52 may enter the switch storage box 11 or may be up to the middle. When the protruding piece 52 protrudes partway through the slit 51, the roller 31 of the working piece 30 enters the slit 51. On the other hand, when the tip of the protruding piece 52 penetrates into the switch storage box 11, the roller 31 does not need to enter the slit 51.
[0028]
In the assembled state, the protruding piece 52 at the tip of the rod 2 enters the slit 51, protrudes toward the microswitch 5, and contacts the roller 31 of the operating piece 30. Therefore, the operating piece 30 is pushed radially outward (in the direction of arrow B) against the urging force of the return spring. When the rod 2 is pulled out of the holder 1 (arrow C direction) and the inner cable 9 is pulled, the projecting piece 52 moves to the left in the figure and moves away from the roller 31. 31 returns radially inward (arrow D direction). As a result, the microswitch 5 is activated. Conversely, when the rod 2 is pushed in the direction of arrow E from the state and the inner cable 9 is pushed, the roller 31 is pushed in the direction of arrow B by the protruding piece 52 of the rod 2 and the switch is switched. The rod 2 does not rotate in the axial direction due to the engagement between the protruding piece 52 and the slit 51, even if the rod 2 does not have a prismatic shape such as a hexagonal shape but is cylindrical. Therefore, there is an advantage that the inner cable 9 is not easily twisted.
[0029]
【The invention's effect】
The PTO operating device of the present invention can directly detect the movement of the rod with the limit switch through the opening formed in the main body of the holder. Therefore, unlike the conventional one, a disk or a large bracket is not required, so that the periphery of the switch can be made small. Moreover, since the switch storage box for accommodating the limit switch so as to be retrofitted is provided, the electrical component can be assembled after the assembly adjustment of the mechanical component. Therefore, there are few failures of electrical parts. In addition, since an independent commercially available limit switch can be used, the reliability is high. According to the mounting method of the PTO operating device of the present invention, there is little failure of the electrical components.
[Brief description of the drawings]
FIG. 1 is a partial cross-sectional side view before assembly showing an embodiment of an operation side of a PTO operation device of the present invention.
2a is a partially cutaway perspective view of the holder in FIG. 1, and FIG. 2b is a cross-sectional view taken along line II-II in FIG.
FIGS. 3a and 3b are sectional views showing an assembled state and an operating state of another embodiment of the PTO operating device of the present invention, respectively.
FIG. 4 is a partial cross-sectional side view showing the entire embodiment of the PTO operating device of the present invention.
FIG. 5 is a cross-sectional view of the main part before assembly showing another embodiment of the operating side of the PTO operating device of the present invention.
FIG. 6 is a partial cross-sectional side view showing an example of an operation side of a conventional PTO operation device.
[Explanation of symbols]
A Operation side 1 Holder 2 Rod 3 Control cable 5 Micro switch 6 Lead wire 7 Connector 8 Conduit 9 Inner cable 11 Switch storage box 12 Conduit mounting part 13 Nut 14 End nut 15 Screw 16 Wall part 17 Small hole 18 Guide hole 18a Bottom wall 19 Window 20 Projection 21 Locking recess 22, 23 Side wall 24 End wall 25 First locking claw 26 Second locking claw 27 Notch 28 Screw 28a Hole 29 O-ring 29a Toothed washer 30 Actuating piece 31 Roller 32 Connector 33, 34 Terminal plate 33 Boot K PTO operation device K1 Operation side K2 Operation side 36 Screw 37 Nut 38 End face 39 Step part 40 Handle 41, 42 Nut 43 Holder 44 Pipe attachment part 45 Guide pipe 46 Rod 47 Joint 48 Bellows boot 49 Grommet 51 Slit 52 Projection piece

Claims (6)

An operating device for remotely operating the opening and closing of the power take-off valve, one end of which is connected to a fixing member on the power take-off valve side, and a flexible conduit;
A push-pull operable inner cord inserted into the conduit slidably and having one end connected to the actuating member of the power take-off valve;
A rod connected to the other end of the inner cable and having a handle at the free end;
A cylindrical holder to which the other end of the conduit is connected and guides the rod in an axially slidable manner;
A switch storage box that is detachably provided on the holder so as to protrude in the radial direction,
The holder is formed with an opening communicating the inside of the holder and the switch storage box,
A limit switch that lights a warning lamp that detects the position of the rod through the opening and displays the operating state of the power take-off valve is stored in the switch storage box ,
An engagement step is formed on the outer periphery of the holder,
Left and right walls holding a holder are provided at the upper part of the switch storage box, and locking claws that elastically engage with the engaging stepped portion are provided at the upper ends of the walls. Power take-off Valve operating device.   The power take-off valve operating device according to claim 1, wherein the opening is a window through which an operating piece of a limit switch is passed, and the operating piece is arranged so as to detect an end of the rod.   The power take-off valve operating device according to claim 1, wherein the opening is a slit extending in an axial direction, and a protrusion is provided on the rod so as to enter the slit.   The holder includes a thin-walled cylindrical conduit mounting portion, a guide hole that guides the rod in an axially slidable manner, and a wall portion interposed between the conduit mounting portion and the guide hole. 2. The power take-off valve operating device according to claim 1, wherein a small hole is formed for passing an inner cord communicating with the guide hole and the conduit mounting portion.   The power take-off valve operating device according to claim 1, wherein one end of the conduit is fixed to a holder on the power take-off valve side, and the holder is attached to the fixing member so as to be capable of adjusting the position in the axial direction.   2. The method of attaching a power take-off valve operating device according to claim 1, wherein the conduit is caulked to the holder on the operating side and the holder on the power take-off valve side, both holders are attached to the mating member, and the operating range of the rod is set. The mounting method of the power take-off valve operating device is based on adjusting the mounting position of the holder on the power take-off valve side and then attaching the switch storage box containing the limit switch to the holder.

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