JP2001130274A - Pump integrated with power take-off device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pump integrated with a power take-off device which is simple in replacement, capable of suppressing the cost of parts for replacement, and high in coupling strength. SOLUTION: In this pump integrated with a power take-off device comprising the power take-off device coupled to a transmission of an engine to take out the power from the transmission, and the pump having an input shaft 21 coupled with an output shaft 11 of the power take-off device via a joint means 5, the joint means 5 comprises one engagement part 51 formed on a coupling end of the output shaft 11, the other engagement part 52 formed on a coupling end of the input shaft 21, and an engaged part 54 (55) to be engaged with the engagement parts at both ends, and further comprises a joint 53 integratedly rotatable with the output shaft 11 and the input shaft 21, and the joint 53 is smaller in breaking torque than the output shaft 11 and the input shaft 21.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power take-out device-integrated pump for driving a hydraulic operating device such as a hydraulic cylinder mounted on a specially equipped vehicle such as a dump truck, and more particularly, to an output shaft of the power take-out device. And a joint structure between the pump and an input shaft of the pump.

[0002]

2. Description of the Related Art FIG. 4 shows an entire configuration of a drive control device provided with a conventional power take-out device integrated pump.

[0003] This drive control device controls the drive of a hydraulic operating device such as a dump cylinder of a dump truck using the power of an engine (not shown). A power take-out device 1 and a gear pump 2 are connected to each end. The switching valve 3 is integrally provided in the housings A and B while being integrally provided in the connected left and right housings A and B.

The power take-out device 1 has bearings 1 at both ends.
An output shaft 11 rotatably supported via 2 and 12;
An output gear 13 rotatably supported at the center of the output shaft 11, and a spline 1 formed at the other end of the output shaft 11;
1a is provided with a clutch gear 14 slidably provided in the axial direction.

The output gear 13 meshes with a power take-out gear (not shown) of an engine transmission and meshes with an input gear 15 which is constantly rotating when the engine is driven.

The clutch gear 14 can be freely engaged with and separated from the output gear 13 via a clutch pawl 17 by moving a shift rod 16 provided in parallel with the output shaft 11 in the axial direction. The transmission of the rotation of the input gear 15 is transmitted to the output shaft 11 via the output gear 13 and the clutch gear 14 by meshing with the output gear 11.

The shift rod 16 is connected via a wire 18 to an operation lever provided at a driver's seat (not shown) or the like, and the operation of the operation lever causes an axial movement operation. The shift rod 16 is provided with an appropriate holding means 19 for holding the moving position.

The gear pump 2 has an input shaft 21 rotatably disposed coaxially with the output shaft 11, and an input shaft 21.
And a driven gear (not shown). The input shaft 21 is connected to the output shaft 11 via the joint means 4.

As shown in FIGS. 4 and 5, the coupling means 4 has a concave portion 41 at one end serving as a connection end of the output shaft 11 and has a recess 41 at one end serving as a connection end of the input shaft 21. The projection 42 is formed, and the rotation of the output shaft 11 is transmitted to the input shaft 21 by fitting the projection 42 into the recess 41.

The switching valve 3 includes an oil passage 31 formed inside the housing B and a spool 32 connected to the shift rod 16, and moves the spool 32 in the axial direction via the shift rod 16. By operating the gear pump 2, the supply path of the pressure oil supplied by driving the gear pump 2 is switched.

Accordingly, the shift rod 16 is moved and operated by operating the operation lever, and the clutch gear 14 is meshed with the output gear 13 so that the rotation of the input gear 15 is output via the output gear 13 and the clutch gear 14. 11, the rotation of the output shaft 11 is transmitted to the input shaft 21 to drive the gear pump 2, and the supply path of the pressure oil supplied by the driving of the gear pump 2 is switched by the switching valve 3, so that the dumping is performed. Supply pressure oil to the cylinder to operate the dump cylinder.

[0012]

However, in the above-mentioned conventional drive control device, the output shaft 11 of the power take-off device 1 and the input shaft 21 of the gear pump 2 are formed by a concave portion 41 formed on the output shaft 11 and an input shaft. 21 is connected by a joint means comprising a convex portion 42 formed on the output shaft 21. Therefore, when an abnormal torque is generated in the output shaft 11 and the input shaft 21 due to, for example, a seizure accident of the gear pump 2, the gear pump 2
A structure for preventing the damage of the output shaft 11 on the power take-out device 1 side by breaking the joint portion (convex portion 42) of the input shaft 21 on the side has to be adopted.

Therefore, when the above-mentioned accident occurs, the input shaft 21 of the gear pump 2 whose joint has been damaged must be replaced, which takes time and the cost of replacement parts. There was a problem that also becomes high.

Further, in the conventional joint structure formed by the concave portion 41 and the convex portion 42, high joint strength cannot be expected, and there is also a problem that the joint structure cannot be applied to driving a large pump due to insufficient strength.

A spline or the like is a joint structure having a large transmission torque. However, there is a problem that the processing cost is relatively high, and the clearance between the male and female is small, so that it is difficult to attach and detach the joint.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and is a power take-out device that can be easily replaced, can reduce the cost of replacement parts, and can be easily processed and has high joint strength. It is an object of the present invention to provide a joint structure between an output shaft of a power take-out device and an input shaft of a pump in a body pump.

[0017]

According to a first aspect of the present invention, there is provided a pump having a power take-out device integrated therein, the power take-out device being connected to a transmission of an engine and taking out power from the transmission, and a pump connected to an output shaft of the power take-out device. And a pump having an input shaft connected through a means, wherein the coupling means includes one of an engagement portion formed at a connection end of the output shaft and the input shaft. And a joint having opposite ends formed at the connection ends of the first and second ends, and an engaged portion engaged with these engagement portions at both ends, and rotatable integrally with the output shaft and the input shaft. The joint has a smaller breaking torque than the output shaft and the input shaft.

According to a second aspect of the present invention, in the power take-out device-integrated pump, at least one of the input shaft side and the output shaft side of the engaged portion of the joint is formed in a polygonal prism cross section. Alternatively, it is made in a concave portion.

[0019]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the structure of the coupling means which is the main part of the power take-out device integrated pump according to the first aspect of the present invention.

The configuration and operation of the entire power control device including the power take-out device integrated pump are the same as those of the prior art except for the coupling means described below. The description in is omitted.

The coupling means 5 connects the output shaft 11 on the power take-out device side to the input shaft 21 on the gear pump side. The coupling means 5 will be described in detail below.

The joint means 5 is formed integrally with one end of the output shaft 11 serving as a connecting end, and is formed integrally with one end of the input shaft 21 serving as a connecting end. A joint having a convex portion 52 as the other engaging portion formed at each end, and concave portions 54 and 55 (refer to FIG. 2) as engaged portions formed at both ends corresponding to the convex portions 51 and 52, respectively. 5
And 3.

The convex portion 51 is a quadrangular prism protruding from the end face of one end of the output shaft 11, and its axis is coaxial with the axis of the output shaft 11.

The projection 52 is a quadrangular prism protruding from the end face of one end of the input shaft 21, and its axis is coaxial with the axis of the input shaft 21.

The joint 53 is formed with a quadrangular prism-shaped fitting hole 53a (see FIG. 2) in which the projections 51 and 52 can be fitted with some clearance. Fitting hole 5
3a is for forming the concave portions 54 and 55, and is formed coaxially with the axis of the joint 53. That is, in this embodiment, the concave portions 54 and 55 are formed by one communicating fitting hole 53a.

The recesses 54 at both end surfaces of the joint 53
A chamfered portion 56 is formed on the peripheral edge of the groove 55 so that the protrusions 51 and 52 can be easily guided into the concave portions 54 and 55 when they are fitted.

The fitting holes 5 forming the recesses 54 and 55
Each of the corner portions 53b of the convex portions 51 and 52 is formed so as to be curved as shown in FIG.
1a and 52a are also chamfered as shown in FIG. 1 so that significant stress concentration does not occur in the concave portions 54 and 55.

The joint 53 is connected to the output shaft 1
1 and the input shaft 21 are designed to have a smaller torque to be broken. Specifically, the output shaft 11 and the input shaft 21 are formed, for example, of a chromium molybdenum steel temper (SCM).
415 etc.), whereas the joint 53
Is formed from a tempered material (for example, S45C, S25C, etc.) having a lower strength than this, for example, a carbon steel material for machine structure.

By configuring the joint means 5 as described above,
When the output shaft 11 and the input shaft 21 have the same shaft diameter, the joint 53 having the simple structure described above can be used and can be manufactured at low cost. The size of the output shaft 1 can be easily adjusted by adjusting the size of the projection 55 to the size of each of the projections 51 and 52.
1 and the input shaft 21 can be connected.

When an abnormal torque is generated in the output shaft 11 and the input shaft 21 due to, for example, a seizure accident of the gear pump 2 or the like, only the joint 53 having a smaller breaking torque than the output shaft 11 and the input shaft 21 is damaged. Will do.

As described above, since only the joint 53 is damaged, the output shaft 11 and the input shaft 21 can be prevented from being damaged, and the repair can be performed simply by replacing the joint 53, so that the repair can be performed quickly. At the same time, the only part to be replaced is the joint 53, and the cost can be reduced.

Further, since the joint structure is such that the protrusions 51 and 52 are inserted into and fitted into the recesses 54 and 55 forming the fitting holes 53a, the strength of the joint can be increased, and a large pump or the like can be used. A wide range of application can be secured as coupling means for driving.

Furthermore, since the projections 51 and 52 are fitted into the recesses 54 and 55 of the joint 53 with a small clearance, the joint means 5 has both the output shaft 11 and the input shaft 21 with this clearance. It also has the function of absorbing the deviation of the axis.

In the present embodiment, the convex portions 51 and 52 formed in a quadrangular prism shape and the concave portions 54 and 55 formed corresponding to the shapes of the convex portions 51 and 52 have been described. The shape of the joint 52 and the concave portions 54 and 55 is not limited to this, and the joint shape of the joint 53 can be such that the output shaft 11 and the input shaft 21 and the joint 53 can be integrally rotated by engagement of the two. If so, the shape may be any.

Although the convex portions are provided on the output shaft 11 and the input shaft 21 side, concave portions having a predetermined shape are formed on the output shaft 11 and the input shaft 21 side, and both end surfaces of the joint 53 correspond to the shapes of the concave portions. Alternatively, a structure having a convex portion may be provided.

Further, the shapes of the projections 51 and 52 may be different on the left and right, for example, the projection 51 may be a triangular prism and the projection 52 may be a spline. 54 and 55 may be formed. Thus, the convex portions 51 and 52 and the concave portions 5
By making the shapes of 4 and 55 different between the left and right of the joint 53, the power take-off device having a shaft end of an arbitrary shape and the pumps can be integrated and connected.

[0038]

As described above, the coupling means includes one engaging portion formed at the connecting end of the output shaft, the other engaging portion formed at the connecting end of the input shaft, and both ends. The part has an engaged part to be engaged with these engaging parts, and comprises a joint rotatable integrally with the output shaft and the input shaft, and the joint has a smaller breaking torque than the output shaft and the input shaft. By doing so, for example, if abnormal torque occurs on the output shaft and the input shaft due to the occurrence of a seizure accident of the gear pump, etc., only the joint will be damaged, which can prevent the output shaft and the input shaft from being damaged, Since the repair is a simple operation of simply replacing the joint, the repair can be performed quickly, and the replacement part is only the joint, so that the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration of a joint means for connecting an output shaft of a power take-out device and an input shaft of a pump, which is a main part of a power take-out device integrated pump of the present invention.

FIG. 2 is a sectional view showing a configuration of a joint.

FIG. 3 is a view of the joint as viewed from one end surface.

FIG. 4 is a cross-sectional view showing the overall configuration of a drive control device including a conventional power take-out device integrated pump.

FIG. 5 is a perspective view showing a configuration of coupling means for connecting an output shaft of the power take-off device and an input shaft of the pump in the conventional power take-out device integrated pump.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 power take-out device 11 output shaft 2 gear pump (pump) 21 input shaft 5 coupling means 51 convex part (one engaging part) 52 convex part (the other engaging part) 53 joint 53 a fitting holes 54, 55 concave parts Engaging part)

Claims (2)

[Claims] 1. A power take-out device comprising: a power take-out device connected to a mission of an engine for taking out power from the transmission; and a pump having an input shaft connected to an output shaft of the power take-out device via coupling means. In the integrated pump, the coupling means includes one engagement portion formed at a connection end of the output shaft, the other engagement portion formed at a connection end of the input shaft, and The output shaft and the input shaft are configured to have an engaged portion that engages with the engagement portion, and the output shaft and the input shaft are integrally rotatable. The joint has a smaller breaking torque than the output shaft and the input shaft. A power take-out device integrated pump. 2. The power take-out device according to claim 1, wherein at least one of the input shaft side and the output shaft side of the engaged portion of the joint is a convex portion or a concave portion formed in a cross-sectional shape of a polygonal prism. Body pump.