JPH075340Y2 - Valve detent mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to an improvement of a detent mechanism used for operating a spool valve of a loader.

(Prior Art) A conventional example will be described with reference to FIG. FIG. 2 is a cross-sectional view showing the configuration of the detent mechanism, in which reference numeral 101 is a housing. A flange 103 is fixed to the upper part of the housing 101. Above the flange 103 is a bellows 105.
The rocking plate chamber 107 is formed by the
A swing plate 109 is housed inside so that it can swing in the direction indicated by arrow a in the figure. An operating rod 113 is connected to the oscillating plate 109 via a bush 111, and the operating rod 113 extends to the outside of the oscillating plate chamber 107. The swing plate 109 is swung in an appropriate direction via the operation rod 113.

Below the flange 103 of the housing 101, a pair of valve mechanisms 11
Five are provided. Explaining the configuration of the valve mechanism 115, an adsorption coil 117 is arranged immediately below the flange 103 while being held by a coil holding portion 119. An upper rod 121 is arranged through the coil holding portion 119 and the flange 103 so as to be slidable in the vertical direction in the figure. Above rod
A suction plate 123 is fixed to the lower end of 121, and the suction plate 123 is constantly urged upward by a spring S. Below the suction plate 123, a lower rod 125 is arranged so as to be slidable in the vertical direction in the figure. A valve mechanism (not shown) is arranged below the lower rod 125, and the pump side port 127 and the tank side port 129 and the load side port 131 are selectively communicated with each other via the valve mechanism.

The valve mechanism 115 located on the right side in the drawing has the same configuration, and the two valve mechanisms 115 are switched by swinging the swing plate 109 in an appropriate direction.

That is, in one valve mechanism 115, the pump side port 127
And the load side port 131 communicate with each other, the load side port 131 of the other valve mechanism 115 is communicated with the tank side port 129.

(Problems to be Solved by the Invention) According to the above conventional configuration, there are the following problems.

First, the contact portion between the oscillating plate 109 and the upper rod 121 is abraded, and the abrasion powder generated by the abrasion enters the sliding portion between the upper rod 121 and the coil holding portion 119 to slide the upper rod 121. There has been a problem that the dynamic operation, particularly the upward return operation is hindered.

Further, the load transmission from the oscillating plate 109 to the upper rod 121 is transmitted from an oblique direction instead of the vertical direction, and at that time, the oscillating plate 109 and the upper rod 121 are in sliding contact with each other. It is considered that the occurrence of Therefore, it has been necessary to devise a method such as attaching another member having good wear resistance to the sliding contact portion.

Next, since the upper rod 121 is located in the coil holding portion 119, the material of the upper rod 121 is limited to the non-magnetic material in order to eliminate the influence of the magnetic flux. Also, the coil holder
119 is also made of electromagnetic soft iron so that it is not affected by magnetic flux. Therefore, since both the upper rod 121 and the coil holding portion 119 are made of a relatively soft material, damage to the sliding portion and sliding failure due to the damage have been a problem.

This invention was made on the basis of such a point, and its purpose is to wear, damage,
It is an object of the present invention to provide a valve detent mechanism capable of maintaining stable operation for a long period of time by eliminating problems such as sliding failure.

(Means for Solving the Problem) The detent mechanism of the present invention comprises an operation lever provided outside the housing to be swingable, a swing plate provided on the operation lever, and a pair of swing levers connected to the swing plate. Push rod,
A valve mechanism that switches according to the movement of this push rod,
This is based on the premise of a valve detent mechanism provided with a suction plate and a suction coil for maintaining the switching position of the valve mechanism.

Based on the above detent mechanism, the push rod of the present invention is connected to the connecting member in the axial direction thereof, and the rocking plate is provided with a pair of pins. A pair of suction plates connected to the inner ends of the housings of a pair of push rods and a pair of suction coils provided below the suction plates are arranged so as to face each other while being movably connected in a direction orthogonal to It has characteristics.

(Operation of the Invention) Since the invention is configured as described above, the rocking plate is rocked by rocking the operation lever. Since a connecting member connected to the push rod is rotatably connected to the swing plate via a pin, if the swing plate swings as described above, the push rod moves up and down. The valve mechanism is switched by the vertical movement of the push rod.

At this time, since the pin connecting the rocking plate and the push rod can move in the radial direction, the pin applies a load to the push rod only in the axial direction thereof.

When the push rod is fully stroked, the suction plate provided at the end of the push rod is sucked by the suction coil.
The valve mechanism will retain its switching position.

(Embodiment of the Invention) An embodiment of the invention will be described below with reference to FIG.
FIG. 1 is a sectional view showing the structure of a valve detent mechanism according to the present embodiment. In the figure, reference numeral 1 is a housing, and a flange 3 is fixed to the upper portion of the housing 1. The housing 1 is provided with a pump side port 5, a tank side port 7, and load side ports 9 and 11, respectively.

While fixing the flange 3 to the housing 1,
A pair of bushes 15, 15 are fixed to the flange 3.

Each of these bushes 15, 15 has a push rod 13,
13 is slidably inserted, but this push rod 1
The upper ends of 3 and 13 are projected above the flange 3. And, at the protruding ends of the push rods 13, 13,
The bolts 17, 17 as a connecting member of this invention are connected.

Hooks 19 and 19 are formed at the upper ends of the bolts 17 and 17, and the open sides of the hooks 19 and 19 face each other. The shape is slightly elliptical so that it becomes the long axis.

Furthermore, although the swing plate 22 is fixed to the operation lever 21,
Pins 23, 23 are fixed to both ends of the swing plate 22. The pins 23, 23 are fitted on the hooks 19, 19 so as to be movable in the longitudinal direction thereof.

Therefore, by rotating the operating lever 21 in the direction indicated by the arrow A in the figure, the push rods 13 and 13 are pushed into or pulled out of the housing 1.

In addition, the dust seal 2 is attached to the sliding surface of the bushes 15 and 15.
5 and 25 are attached to prevent dust from entering from the outside. Oil sump spaces 27, 27 are formed in the sliding surfaces of the bushes 15, 15 at the lower positions of the dust seals 25, 25 in the figure, and lubricating oil is enclosed in the oil sump spaces 27, 27.

Adsorption plates 31, 31 are fixed to the lower ends of the push rods 13, 13 with bolts 29, 29. Coil holders 35, 35 are provided below the suction plates 31, 31, and the holders
Adsorption coils 33, 33 are held by 35, 35.

Further, valve mechanisms (not shown) are arranged below the adsorption coils 33, 33, respectively, and reference numerals 37, 37 in the figure denote valve plungers thereof.

The operation will be described based on the above configuration.

For example, when the operation lever 21 is rotated counterclockwise from the neutral position in the figure, the push rod 13 shown on the left side in the figure is pushed downward and the bolt 29 moves the valve plunger.
Push in 37. As a result, the valve mechanism located on the left side in the figure operates.

At this time, as the push rod 13 descends, the adsorption plate 31 also descends, so that the adsorption plate 31 is adsorbed by the adsorption coil and the operating lever 21 is held at that position during the full stroke of the push rod 13. .

Reference numerals 32 and 32 in the figure are springs for keeping the operation lever 21 in the neutral position.

As described above, according to this embodiment, the following effects can be expected.

When the operating lever 21 is swung, the pin fixed to the swing plate 22
The bolts 17, 17 are pushed and the push rods 13, 13 are pushed in while the 13, 13 move along the long axis direction in the hooks 19, 19. Therefore, the operating force of the operating lever always acts on the push rods 13 in the axial direction.

Therefore, unlike the conventional case, the rocking plate and the push rod do not rub each other, or the load of the rocking plate does not act obliquely on the push rod. As a result, the contact portion of each member is almost not worn, and the operation of the operation lever is light.

Further, since the adsorption coil 33 is provided in the coil holding portion 35 arranged below the bush 15, the adsorption coil and the push rod 13 can be completely separated. Therefore,
When selecting the material of the push rod 13, it is not necessary to consider the influence of the magnetic flux, and a material having excellent wear resistance can be used.

Since the dust seal 25 is attached to the bush 15,
It is possible to prevent foreign matter from entering from the outside and eliminate a situation such as sliding failure due to the entry of foreign matter.

In addition, an oil sump space 27 is formed in the bush 15,
Since the lubricating oil is enclosed, sliding of the push rod 13 can be made smooth, and sliding failure due to generation of abrasion powder can be prevented.

(Effect of the Invention) According to the detent mechanism of the valve according to the present invention, the pin connecting the oscillating plate and the push rod moves in the radial direction, and the load is applied only to the axial direction of the push rod. Therefore, unlike the conventional case, the push rod and the oscillating plate do not rub each other, or the load of the oscillating plate does not act obliquely on the push rod. Therefore, the contact portion of each member is hardly worn and the operation of the operation lever is light.

Further, since the suction coil is arranged below the suction plate so as to face each other, the suction coil and the push rod can be completely separated. Therefore, when selecting the material of the push rod, it is not necessary to consider the influence of the magnetic flux, and a material having excellent wear resistance can be used.

[Brief description of drawings]

1 is a sectional view of a valve detent mechanism according to an embodiment of the present invention, and FIG. 2 is a sectional view of a conventional valve detent mechanism. 1 ... Housing, 13 ... Push rod, 21 ... Operating lever, 25 ... Dust seal, 27 ... Oil storage space, 31 ... Adsorption plate,
33 ... Adsorption coil.

Claims (1)

[Scope of utility model registration request] 1. An operating lever provided swingably outside a housing, a swing plate provided on the operating lever, a pair of push rods connected to the swing plate, and a push rod according to movement of the push rod. In a detent mechanism of a valve including a valve mechanism that switches in accordance with the above, and an adsorption plate and an adsorption coil that maintain the switching position of the valve mechanism, a coupling member is coupled to the push rod in the axial direction thereof, and the swing plate is also coupled. A pair of pins is provided to the connecting member, while the pin is movably connected to the connecting member in a direction orthogonal to the axis thereof, a pair of suction plates connected to the housing inner end portions of the pair of push rods, A detent mechanism for a valve, characterized in that a pair of suction coils provided below the suction plate are arranged to face each other.