JP2004306734A - Oil pump and cab tilting device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cab tilting device in which it can be manually operated and an external driving power may also be used. <P>SOLUTION: This cab tilting device comprises a tilting cylinder device 3 installed between a cab and a frame to cause the cab to be tilted, and an oil pump 13 for supplying hydraulic oil to a raising oil passage 11 and a lowering oil passage 12 of the tilting cylinder device 3. The oil pump 13 is provided with a pair of cylinder chambers 30A, 30B arranged around a rotating shaft 24, and a pair of pistons 32A, 32B slidably fitted into both cylinder chambers and advanced or retracted by the rotating shaft 24. Both pistons are connected to be moved integrally by a connecting member 33 made of resilient material and formed into a C-ring shape. With such an arrangement as above, because of two discharges either a capacity or a driving force of the oil pump can be reduced to its half amount, a usage of an impact wrench can be attained and a labor of manual work can be reduced. Accordingly, a manufacturing cost of the cab tilting device and its running cost are reduced. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an oil pump, and more particularly to an oil pump that is effectively used for a cab tilt oil pump that supplies oil pressure to a cab tilt device mounted on a cab-over-engine vehicle.
[0002]
[Prior art]
A medium-sized or large-sized cab-over type truck is equipped with a cab tilt device so that inspection and maintenance of an engine portion and the like can be easily performed. In this cab tilt device, a tilt cylinder device driven by an oil pump for cab tilt is interposed between the cab and the frame, and an oil pump for cab tilt is provided in a raising-side oil supply / discharge passage of the tilt cylinder device. The cab is lifted by supplying pressure oil to the cab, and the cab is lowered by supplying pressure oil to the lower-side supply / discharge oil passage.
[0003]
As a conventional cab tilt device, a cab tilt oil pump is configured to be driven by a DC motor (hereinafter referred to as an electric cab tilt device), and a cab tilt oil pump is driven manually. (Hereinafter referred to as a manual cab tilt device).
[0004]
A reciprocating piston pump is used as an oil pump for the cab tilt of the former electric cab tilt device, and the input shaft of the reciprocating piston pump is rotated by a DC motor to reciprocate a piston slidably fitted into the cylinder chamber. It is configured to perform a pumping action by being moved. Incidentally, the theoretical displacement volume of the reciprocating piston pump is set to a small capacity (about 0.2 cc / rev) from the relation between the output of the DC motor and the speed of the cab tilt.
[0005]
In general, in an electric cab tilt device, an emergency manual pump is provided in order to cope with an emergency such as a failure of a DC motor. Generally, a reciprocating constant displacement oil pump is used as an emergency manual pump.In an emergency, insert the provided driver etc. into the socket attached to the piston and reciprocate the piston. Thus, a pump operation is performed. Incidentally, the theoretical displacement volume of a reciprocating constant displacement oil pump as an emergency manual pump is a medium capacity (about 1 cc per one reciprocating operation) from the relationship between the operating force and the number of operations of the pump and the cab tilt speed. Is set.
[0006]
In an electric cab tilt device, a reciprocating piston pump driven by a DC motor is used as an oil pump for the cab tilt, and an emergency manual pump is additionally provided, so that initial costs and running costs of the cab tilt device increase. In addition, there is a problem in that the weight of the cab-over type truck increases the fuel efficiency and the like. In order to solve this problem, an electric hydraulic pump for tilting has been proposed in which a drive shaft of an electric motor is extended and tool engagement means for engaging a tool for manual rotation with the drive shaft is provided. (See Patent Document 1).
[0007]
Generally, a reciprocating constant displacement oil pump is used as the oil pump for the cab tilt of the latter manual cab tilt device.In use, the lever provided is inserted into the socket attached to the piston and the piston reciprocates. It is configured to perform a pumping action by being moved. Incidentally, the theoretical displacement volume of this reciprocating constant displacement oil pump is set to a large capacity (about 4 cc per one reciprocating operation) from the relation between the operating force and the number of times of operation of the pump and the cab tilt speed.
[0008]
[Patent Document 1]
JP 2000-264259 A
[0009]
[Problems to be solved by the invention]
In an electric cab tilt device in which a tool engagement means is provided on a drive shaft of an electric motor, a large amount of labor and time are required for tilting the cab because a theoretical displacement volume of an oil pump is set to a small capacity. There is a problem that it is spent.
[0010]
In a manual cab tilt device, since a piston needs to be reciprocated by a long lever when an oil pump for cab tilt is manually driven, not only a large amount of labor and time is wasted to tilt the cab, but also the cab tilt operation is difficult. In this case, there is a problem that a large operation space is required.
[0011]
An object of the present invention is to provide an oil pump that can be manually operated and that can use external power, and a cab tilt device using the oil pump.
[0012]
[Means for Solving the Problems]
An oil pump for solving the above-described problem includes a rotating shaft, a pair of radially arranged cylinder chambers facing each other around the rotating shaft, and slidably fitted in the pair of cylinder chambers in a radial direction. And a pair of pistons respectively moving forward and backward in these cylinder chambers with the rotation of the rotary shaft, wherein the pair of pistons are connected so as to move integrally by a connecting member. .
[0013]
A cab tilt device for solving the above-mentioned problem includes a tilt cylinder device interposed between a cab and a frame for tilting the cab, and a hydraulic oil supply line on the up-side and down-side oil supply / discharge passages of the tilt cylinder device. An oil pump for supplying oil. The oil pump is provided with a rotary shaft, a pair of radially arranged cylinder chambers facing each other around the rotary shaft, and radially slides in the pair of cylinder chambers. A pair of pistons which are freely inserted and advance and retreat in the cylinder chambers with the rotation of the rotary shaft, respectively, and the pair of pistons are connected so as to move integrally by a connecting member. Features.
[0014]
When the cab is tilted in the cab tilt device described above, for example, even when the oil pump is operated manually, the oil pump includes a pair of cylinder chambers and a piston, so that the pressure oil is supplied to and discharged from the oil pump. Can be supplied sufficiently. Further, since the pair of cylinder chambers are arranged radially opposite to each other, fluctuations in driving force when the rotation shaft of the oil pump is rotated by human power are reduced.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
[0016]
As shown in FIG. 1, the cab tilt device according to the present embodiment includes a tilt cylinder device 3 interposed between a cab 1 and a frame 2 and performing a tilt operation of the cab 1 by a hydraulic expansion and contraction operation. Have. That is, the cab 1 is rotatably supported in the front-rear direction by the fulcrum 1 a of the frame 2, and the upper end of the piston rod 4 of the tilt cylinder device 3 is pivotally attached to the cab 1 via the link, The lower end of the cylinder 5 is pivotally attached to the frame 2 so as to be freely rotatable.
[0017]
As shown in FIG. 2, a hydraulic drive circuit 10 of the tilt cylinder device 3 includes an upside oil supply / discharge passage (hereinafter, referred to as an upside oil passage) 11 and a downside supply / discharge oil passage (hereinafter, lowering oil passage). A side oil passage) 12, an oil pump 13, a tank 14, and a manual switching valve (hereinafter, referred to as a switching valve) 15. The raising-side oil passage 11 is fluidly connected to a frame-side hydraulic chamber (hereinafter, referred to as a raising-side hydraulic chamber) 5 a of the cylinder 5, and the lowering-side oil passage 12 is a cab-side hydraulic chamber (hereinafter, lowering) of the cylinder 5. (Referred to as a side hydraulic chamber). The switching valve 15 is a four-port, two-position, manually-operated switching valve, and the load port a of the up-side oil passage 11 is connected to the tank port T during normal operation (during running with the cab down). The load port b of the lower oil passage 12 is connected to the pump port P. At the time of switching (tilting up) by operating the switching lever 15a, the load port a of the upward oil passage 11 is connected to the pump port P, and the load port b of the downward oil passage 12 is connected to the tank port T. It is configured as follows. A first pilot operated check valve (hereinafter, referred to as a first pilot check valve) 16 is interposed in the upward oil passage 11, and a second pilot operated check valve is disposed in the downward oil passage 12. A check valve (hereinafter, referred to as a second pilot check valve) 17 is interposed. The first pilot check valve 16 and the second pilot check valve 17 block the flow from the cylinder 5 side to the switching valve 15 side when the hydraulic pressure is less than a preset pilot pressure value, and Each is configured to allow the flow when the pressure value becomes equal to or higher than the pressure value.
[0018]
3 to 8 show an oil pump 13 according to the present embodiment. The oil pump 13 is constituted by a fixed cylinder type radial piston pump as shown in FIGS. That is, the oil pump 13 includes a casing 21 formed in a substantially rectangular parallelepiped shape, and a casing 22 for forming the tank 14 is covered on one end surface of the casing 21. A rotating shaft 24 is inserted into the casing 21 from the housing 22 side and rotatably supported by a pair of bearing metals 23, 23. An end of the rotating shaft 24 opposite to the housing 22 is provided outside the casing 21. It is projected to. A mounting portion 25 to which an impact wrench 50 and a manual wrench 51 are removably mounted is formed at the protruding end of the rotating shaft 24. In the present embodiment, the mounting portion 25 is formed in a hexagonal head shape so that the impact wrench 50 and the manual wrench 51 can be removably mounted via the coupling 25a.
[0019]
As shown in FIG. 4, a cam 26 is formed at an intermediate portion of the rotating shaft 24 so as to be eccentric with respect to the center of rotation with an eccentric amount E, and a cam ring 28 is wound around the outer periphery of the cam 26. Is mounted via. The winding bush may be a rolling bearing. A cam ring accommodating chamber 29 is provided at a portion corresponding to the cam ring 28 of the casing 21, and a pair of cylinder chambers 30 </ b> A and 30 </ b> B are formed outside the cam ring accommodating chamber 29 of the casing 21 on a normal line in the eccentric direction of the cam 26. They are arranged radially opposite to each other, and are opened so that one end (hereinafter, referred to as an inner end) opens in the cam ring storage chamber 29. Plugs 31A and 31B for closing the outer openings are screwed into outer end portions of the two cylinder chambers 30A and 30B, respectively. A pair of pistons 32A, 32B are slidably fitted in the two cylinder chambers 30A, 30B, respectively, and the inner end faces of the pistons 32A, 32B are inserted into the cam ring housing chamber 29 so as to be able to advance and retreat. A connecting member 33 formed in a C-ring shape by using an elastic material is disposed at an end of the cam ring storage chamber 29 opposite to the mounting portion 25, and the pair of pistons 32A and 32B are connected to the connecting member 33. Are connected so as to move integrally with each other via a pair of pins 35, 35. A pair of tool engagement holes 34, 34 are respectively formed at both ends of the groove in the C-ring shape of the connecting member 33, and a tool is engaged with the pair of tool engagement holes 34, The pair of pistons 32A, 32B is engaged via the pair of pins 35, 35 in a state where the connecting member 33 is opened against the force, so that the connecting member 33 is formed inside the pair of pistons 32A, 32B. The end surface is configured to be constantly pressed against the outer peripheral surface of the cam 26 with an elastic force against the inertia force, frictional resistance, and the like of the piston when the pump is driven.
[0020]
It is desirable that the theoretical displacement volume by the cylinder chambers 30A, 30B and the pistons 32A, 32B be set to 1.0 to 2.0 cc / rev. If the theoretical displacement volume is less than 1 cc / rev, it takes too much time to manually tilt the cab because the amount of oil discharged when the rotary shaft of the oil pump is rotated once is small. On the other hand, if the theoretical displacement volume exceeds 2 cc / rev, it becomes too heavy to rotate when manually tilting. Incidentally, in the present embodiment, the theoretical displacement volume of the oil pump is set to about 1.3 cc / rev, and the oil pump 13 is set so that the rotation axis of the oil pump 13 completes the tilting of the cab at 200 to 300 rotations. Have been.
[0021]
The suction passages 36A, 36B are respectively formed on the side walls of the two cylinder chambers 30A, 30B in the casing 21 so that one end thereof communicates with the side surfaces of the two cylinder chambers 30A, 30B. The other end is communicated with suction ports 37A and 37B, respectively, which are opened to communicate with the tank 14 on the side wall of the casing 21. Filters 38A and 38B are respectively attached to both suction ports 37A and 37B. Valve paths 39A, 39B are respectively opened at the outer ends of both pistons 32A, 32B, and one end of both valve paths 39A, 39B communicates with both suction ports 37A, 37B. The other end of 39B communicates with both cylinder chambers 30A and 30B. Each suction valve 40A, 40B is interposed in the middle of both valve paths 39A, 39B, respectively, and the two suction valves 40A, 40B only flow from each suction port 37A, 37B side to each cylinder chamber 30A, 30B side. Is configured to allow.
[0022]
As shown in FIG. 5, the casing 21 has valve chambers 41A and 41B respectively opened between the plugs 31A and 31B and the cylinder chambers 30A and 30B. Respectively house the valve boxes 42A and 42B. Cylinder chambers 43A, 43B into which the outer ends of both pistons 32A, 32B are reciprocally fitted into the inner ends of both valve boxes 42A, 42B, respectively, are laid down on the extension lines of both cylinder chambers 30A, 30B. The two cylinder chambers 43A and 43B constitute a part of both cylinder chambers 30A and 30B. Sealing rings 44A, 44B seal the two cylinder chambers 43A, 43B, the two cylinder chambers 30A, 30B, and the two pistons 32A, 32B on the inner end surfaces of the two valve boxes 42A, 42B at the bottoms of the two valve chambers 41A, 41B. It is interposed so as to make. Discharge valves 45A and 45B are interposed between the valve boxes 42A and 42B and the plugs 31A and 31B, respectively. The discharge valves 45A and 45B are connected to both the valve chambers 43A and 43B from the valve chambers. It is configured to allow only circulation to the 41A and 41B sides. Discharge passages 46A and 46B are opened on the side walls of the two valve chambers 41A and 41B in the casing 21 so as to communicate with the two valve chambers 41A and 41B. The two discharge passages 46A and 46B are connected in series with each other. I have.
[0023]
As shown in FIG. 5, in the present embodiment, the switching valve 15 is integrally incorporated in the casing 21. The switching valve 15 includes a valve body 15b (see FIG. 6) operated by the switching lever 15a shown in FIG. 3, and the valve body 15b is rotatably fitted into a valve chamber 15c opened in the casing 21. I have. A pump port P to which the discharge passage 46A is connected, an up-side port a to which the up-side oil passage 11 is connected, and a down-side port b to which the down-side oil passage 12 is connected to the inner periphery of the valve chamber 15c. A tank port T connected to the tank 14 is opened. Although not shown in FIG. 5, the relief passage 47 shown in FIG. 2 is opened in the casing 21 of the oil pump 13, and a relief valve 47A is provided in the relief passage 47. The relief valve 47A prevents the hydraulic pressure of the hydraulic circuit from being abnormally high due to some failure.
[0024]
Next, a method of using the cab tilt device according to the above configuration and the operation thereof will be described.
[0025]
When the cab 1 is tilted up at an automobile repair shop or the like, the switching lever 15a of the switching valve 15 is switched by 90 degrees from the position shown by the imaginary line in FIG. 3 to the horizontal position shown by the solid line. Then, the valve element 15b is switched to the position shown in FIG. 2, the pump port P of the switching valve 15 is connected to the load port a, and the tank port T is connected to the load port b. When the cab lock of the cab lock device 60 shown in FIG. 1 is released, a buzzer (not shown) starts to sound. Subsequently, as shown in FIG. 7, an impact wrench 50 provided at an automobile repair shop or the like is mounted on the mounting portion 25 of the rotary shaft 24 of the oil pump 13 by an operator. When the air of the compressor is supplied to the impact wrench 50, the rotating shaft 24 of the oil pump 13 is forcibly rotated by the rotating force of the impact wrench 50. That is, the oil pump 13 is operated by the driving force of the impact wrench 50.
[0026]
In FIG. 4, when the rotary shaft 24 of the oil pump 13 is rotated by the impact wrench 50 and the cam 26 is eccentrically rotated, the pair of pistons 32A and 32B reciprocate, respectively, so that the oil in the tank 14 is removed from both filters 38A and 38B. , And is discharged into the two cylinder chambers 30A, 30B via the cylinder chambers 43A, 43B, and discharged from the two cylinder chambers 43A, 43B to the two discharge paths 46A, 46B shown in FIG. The two discharge paths 46A and 46B are connected in series with each other, and the downstream end of one discharge path 46A is connected to the pump port P of the switching valve 15, so that both oils are sent to the pump port P. The oil in the pump port P is sent to the up port a depending on the direction of the valve port of the valve body 15b, and is sent to the up oil path 11 shown in FIG. The pressurized oil fed to the raising oil passage 11 flows into the raising hydraulic chamber 5a of the cylinder 5 of the tilt cylinder device 3 through the first pilot check valve 16, and the piston rod 4 is extended to operate the cab. Lift 1 from the frame 2 and tilt it up.
[0027]
Here, in order to extend the piston rod 4, it is necessary to discharge the pressure oil in the lower hydraulic chamber 5 b of the cylinder 5. In FIG. 2, when the oil pressure in the raising oil passage 11 rises and becomes equal to or higher than the pilot pressure value set in the second pilot check valve 17, the second pilot check valve 17 opens. When the second pilot check valve 17 is opened, the pressure oil in the lower hydraulic chamber 5b of the cylinder 5 is supplied to the second pilot check valve 17 of the lower oil passage 12, the lower oil passage 12 of FIG. It is discharged to the tank 14 via the 15 valve bodies 15b and the tank port T. Therefore, the piston rod 4 of the tilt cylinder device 3 is extended and the cab 1 can be tilted up.
[0028]
When the cab 1 is tilted up to a preset position, the buzzer that sounds when the cab lock is released stops, and the worker stops the operation of the oil pump 13 by the impact wrench 50. At this time, the lowering of the cab 1 that has been tilted up is automatically prevented by the operation of the first pilot check valve 16 shown in FIG. When the oil pump 13 stops, the oil pressure between the first pilot check valve 16 of the raising oil path 11 and the oil pump 13 decreases due to oil leakage inside the oil pump 13. When the oil pressure falls below the set pilot pressure value, the second pilot check valve 17 closes. When the second pilot check valve 17 is closed, the pressure oil in the lower hydraulic chamber 5b of the cylinder 5 cannot be discharged, so that the piston rod 4 of the tilt cylinder device 3 cannot be extended.
[0029]
Thereafter, when the operator attempts to tilt down the cab 1, the switching lever 15a is switched from the horizontal direction to the tilt down side in the vertical direction in FIG. Subsequently, the oil pump 13 is operated by the driving force of the impact wrench 50, and the pressure oil of the oil pump 13 is pumped to the lower oil passage 12. The pressure oil sent to the lower oil passage 12 flows into the lower hydraulic chamber 5b of the cylinder 5 of the tilt cylinder device 3 through the second pilot check valve 17, and the extended piston rod 4 is shortened. The cab 1 is tilted down. Here, in order for the piston rod 4 to perform the shortening operation, it is necessary to discharge the pressure oil in the raising hydraulic chamber 5 a of the cylinder 5. In the present embodiment, when the pressure of the first pilot check valve 16 connected to the lower oil passage 12 becomes equal to or higher than the pilot pressure value set for the first pilot check valve 16, the first pilot The check valve 16 opens. In FIG. 2, when the first pilot check valve 16 is opened, the hydraulic oil in the raising hydraulic chamber 5a of the cylinder 5 passes through the first pilot check valve 16 and the valve element 15b of the switching valve 15 to the tank 14b. , The piston rod 4 of the tilt cylinder device 3 can be shortened and the cab 1 can be tilted down.
[0030]
For example, in a case where the cab 1 is tilted up and down in a place where an impact wrench is not always provided other than an automobile repair shop, such as in an emergency, as shown in FIG. A manual wrench 51 is mounted on the mounting portion 25 of the rotary shaft 24 of the oil pump 13 via a coupling 25a by an operator, and the rotary shaft 24 of the oil pump 13 is rotated by manual force applied to the manual wrench 51. As a result, the oil pump 13 is operated manually.
[0031]
According to the embodiment, the following effects can be obtained.
[0032]
1) Attach an impact wrench, which is usually provided in an automobile maintenance shop, to the mounting part of the rotary shaft of the oil pump for cab tilt, and drive the rotary shaft of the oil pump for cab tilt by the driving force of the impact wrench by supplying air from the compressor. Can be rotated. That is, since the oil pump for cab tilt can be operated without human power by using the external power, the cab tilt device does not need to always have a DC motor, and furthermore, a great deal of labor and time is wasted. The cab can be tilted up and down without having to do so.
[0033]
2) For example, when it is necessary to tilt the cab up and down in a place where the impact wrench is not installed, such as in an emergency, use a manual wrench on the mounting part of the rotating shaft of the oil pump for cab tilt. By installing the oil pump, the oil pump for the cab tilt can be operated manually, so that it is not necessary to separately provide an emergency manual oil pump.
[0034]
3) By omitting the installation of the DC motor and the auxiliary equipment for the emergency manual oil pump, it is possible to reduce the weight of the cab tilt device and to significantly reduce the manufacturing cost and running cost. Fuel efficiency and the like can be reduced.
[0035]
4) In the oil pump, a pair of cylinder chambers and pistons are radially arranged, and both pistons are connected so as to move integrally by a connecting member, so that a pump having one cylinder chamber and one piston and the same theoretical displacement volume is provided. Is advantageous in the following respects.
i. Since the oil is discharged twice per rotation of the rotary shaft of the oil pump, the capacity of the cylinder chamber can be reduced by half.
ii. Since the capacity of the cylinder chamber is one half, the driving force of the rotary shaft of the oil pump can be reduced to about one half.
iii. Since the driving force is about one-half, a small impact wrench can be used, and the manual operation can be performed with little effort.
[0036]
5) In the oil pump, a pair of cylinder chambers and pistons are radially arranged, and both pistons are connected so as to move integrally by a connecting member, so that the pump has one cylinder chamber and one piston and the same theoretical displacement volume. In comparison with the oil pump, since the pressure oil is continuously discharged per rotation of the rotation axis of the oil pump, the driving force when rotating the rotation axis of the oil pump by manual power through a manual wrench is reduced per rotation. Since it becomes substantially equal, the operation feeling is improved, and a sudden load change is eliminated, it is possible to prevent an injury or the like of the operator.
[0037]
6) By pressing the pair of pistons against the outer periphery of the cam ring with an elastic force by the connecting member, there is no gap between the piston and the cam ring, and noise can be prevented from being generated from the abutting portion between the piston and the cam. In addition, wear of the piston and cam (winding bush and cam ring) can be prevented, and a decrease in the pump discharge amount due to a decrease in the stroke of the piston can be prevented.
[0038]
7) When the cam, cam ring, and winding bush can be processed to have a perfect circle without distortion and the same diameter without variation, a pair of pistons should always be pressed against the outer periphery of the cam using an inelastic connecting member. Can be. However, it is impossible in practice because there are processing errors and assembly errors. That is, by pressing the pair of pistons against the outer peripheral surface of the cam with the elastic connecting member, it is possible to absorb the processing error and the assembly error of the pair of pistons and the cam. Accuracy can be reduced.
[0039]
8) A connecting member which is formed in a C-ring shape by using an elastic material, and a pair of pistons is engaged with the connecting member by pins to press the pair of pistons against the outer periphery of the cam with an elastic force. Can be easily manufactured, and the manufacturing cost can be reduced.
[0040]
Note that the present invention is not limited to the above-described embodiment, and it goes without saying that various changes can be made without departing from the gist of the present invention.
[0041]
For example, the theoretical displacement volume of an oil pump for cab tilt is not limited to about 1.3 cc / rev, and may be 1.0 to 1.0 in accordance with the relationship between the cab tilt speed and the rotation speed by an impact wrench and a manual wrench. It is desirable to set it to 2.0 cc / rev.
[0042]
Specific structures of the tilt cylinder device, the hydraulic drive circuit, and the like are not limited to the above embodiment.
[0043]
The connecting member for connecting the pair of pistons with elastic force is not limited to a C-ring shape using a leaf spring material, but may be formed into a ring shape using a wire-working spring.
[0044]
The oil pump may be configured such that an electric impact wrench, an electric motor, a glasses wrench, or the like can be used as a driving means thereof.
[0045]
【The invention's effect】
As described above, according to the present invention, it is possible to increase the discharge flow rate of the entire pump while setting the theoretical displacement capacity of one piston of the pump small, so that the manufacturing cost and the running cost of the cab tilt device can be reduced. Can be reduced.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a cab-over type vehicle equipped with a cab tilt device according to an embodiment of the present invention.
FIG. 2 is a hydraulic circuit diagram of the cab tilt device.
FIG. 3 is a front view showing an oil pump.
FIG. 4 is a sectional view taken along the line IV-IV in FIG. 3;
FIG. 5 is a sectional view taken along the line VV of FIG. 4;
FIGS. 6A and 6B are enlarged partial cross-sectional views showing switching of the switching valve, wherein FIG. 6A shows a cab-tilt-down state, and FIG. 6B shows a cab-tilt-up state.
FIG. 7 is a side view showing a state where the impact wrench is mounted on the oil pump.
FIG. 8 is a side view showing a state where a manual lever is mounted on the oil pump.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Cab, 1a ... Support point, 2 ... Frame, 3 ... Cylinder device for tilt, 4 ... Piston rod, 5 ... Cylinder, 5a ... Frame side hydraulic chamber (upward hydraulic chamber), 5b ... Cab side hydraulic chamber (downward side) Hydraulic chamber), 10: hydraulic drive circuit, 11: up-side supply / discharge oil path (up-side oil path), 12: down-side supply / discharge oil path (down-side oil path), 13: oil pump for cab tilt, 14 ... Tank, 15: manual switching valve (switching valve), 15a: switching lever, 15b: valve body, 15c: valve chamber, 16: first pilot check valve, 17: second pilot check valve, 21: casing , 22 ... housing, 23 ... bearing metal, 24 ... rotating shaft, 25 ... mounting part, 25a ... coupling, 26 ... cam, 27 ... winding bush, 28 ... cam ring, 29 ... cam ring storage chamber, 30A, 30B ... cylinder Room, 31A, 31 ... Plug, 32A, 32B ... Piston, 33 ... Connecting member, 34 ... Tool engaging hole, 35 ... Pin, 36A, 36B ... Suction path, 37A, 37B ... Suction port, 38A, 38B ... Filter, 39A, 39B ... Valve Road, 40A, 40B ... suction valve, 41A, 41B ... valve chamber, 42A, 42B ... valve box, 43A, 43B ... cylinder chamber, 44A, 44B ... seal ring, 45A, 45B ... discharge valve, 46A, 46B ... discharge Road, 47 ... Relief passage, 47A ... Relief valve, 50 ... Impact wrench, 51 ... Manual wrench (manual lever), 60 ... Cas lock device.

Claims (4)

A rotating shaft, a pair of radially disposed cylinder chambers facing each other around the rotating shaft, and slidably fitted in the pair of cylinder chambers in a radial direction so that these cylinders are rotated with the rotation of the rotating shaft. An oil pump, comprising: a pair of pistons respectively moving forward and backward in the chamber, wherein the pair of pistons are connected so as to move integrally by a connecting member. A tilt cylinder device interposed between the cab and the frame for tilting the cab, and an oil pump for supplying pressure oil to a raising / lowering oil supply / discharge passage of the tilt cylinder device; The oil pump includes a rotating shaft, a pair of radially arranged cylinder chambers facing each other around the rotating shaft, and is slidably fitted in the pair of cylinder chambers in a radial direction so as to rotate with the rotation of the rotating shaft. A cab tilt device comprising: a pair of pistons respectively moving forward and backward in each of the cylinder chambers, wherein the pair of pistons are connected so as to move integrally by a connecting member. The oil pump according to claim 1, wherein the connecting member is configured to press the pair of pistons against an outer peripheral surface of the rotation shaft with elastic force. 4. The oil according to claim 1, wherein the connecting member is formed in a C-ring shape using an elastic material, and a part thereof is engaged with each of the pair of pistons. 5. pump.

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