JPH0198786A - Oil controlling valve - Google Patents

Abstract

PURPOSE:To obtain a valve capable of controlling the flow rate of oil according to the variation of oil viscosity along with the change of temperature by performing flow rate control utilizing a spring made of shape memory alloy. CONSTITUTION:A spool-like valve plug 28 for varying the opening of an oil passage 21 is energized in the directions opposite to each other by a pair of springs 26 and 27. At least one of the two springs 26 and 27 is made of shape memory alloy. The use of an oil controlling valve constituted in such way as mentioned above in a door closer, for example, prevents the closing speed of the door closer from being affected by the change of temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention This invention relates to an oil flow control valve used primarily to adjust the closing speed of a door closer.

BACKGROUND ART FIGS. 4 and 5 show the structure of a conventional door closer of this type. In Fig. 4, the closer body (1) is attached to the door, and at the tip of the arm (2) pivotally attached to the closer body (1),
One end of the connecting rod (3) is pivotally connected, and the other end of the connecting rod (3
) The other end is pivoted to the building side. Said arm (2)
is the main shaft (see Fig. 5) which is supported on the door closer body (1).
4). A pinion (5) formed on this main shaft (4) meshes with a rack (7) on the side of a piston (6) inserted into the closer body (1).

When the door is opened, the arm (2) rotates, and as the arm (2) rotates, the main shaft (4) similarly rotates,
Via the pinion (5) and rack (7), the piston (6) is slid to the right in the figure against the force of the spring (8).

Figure 5 shows a state in which the door has been opened and moved to the right, and when the door is released from this state, the piston (7) is pushed back in the opposite direction by the force of the spring (8). , which causes the arm (2) to pivot in the opposite direction and close the door. At that time, the oil filled in the closer body (1) flows from the chamber (9) on the opposite side to the spring (8) side of the piston (7) to the oil passage (10) also formed in the door closer body (1). ) into the spring-side chamber (II). In this conventional example, an adjusting screw (12) for changing the cross-sectional area of the oil passage (10) is provided at one location of the oil passage (10). By changing the penetration depth, it is possible to change the speed at which the oil flows, that is, the speed at which the door closes.

Problems to be Solved by the Invention Therefore, in the above-mentioned conventional door closer, the closing speed of the door closer can be changed by changing the oil flow speed, but this speed change also depends on changes in temperature. Due to the accompanying changes in the viscosity of the oil, it is difficult to maintain it constant throughout the year, and therefore the adjusting screw (12) must be adjusted seasonally. However, it is unreasonable to expect users to make this adjustment, and in the end, in winter when the viscosity is high, the closing speed of the door becomes slow, and by forcing a door that is not working properly, it may cause problems such as oil leakage from the door closer itself. Currently, there are problems such as malfunctions, or because the viscosity is low in summer, the closing speed becomes too fast, causing vibrations and noise.

In addition, in order to solve the problem of scorching, the ultimate solution is to use an oil whose viscosity changes little with temperature, but such an oil with a constant viscosity has not actually been developed.

In view of this problem, the present invention provides a valve that can control the flow rate according to changes in the viscosity of oil due to seasonal temperature changes, and aims to eliminate the drawbacks of the door closer, etc. It has been done.

Means for Solving the Problems And in order to achieve the above object, the present invention provides a valve body (23) that moves in a direction to change the open area of the oil passage (21), and a valve body (23) that moves in a direction to change the open area of the oil passage (21). A pair of spring bodies (26) (27) that act in opposite directions with respect to the moving direction of
), and is characterized in that at least one of these spring bodies (26) and (27) is made of a shape memory alloy whose spring constant changes according to temperature changes.

Effect According to the configuration of the present invention, one of the spring bodies (27) made of a shape memory alloy changes its spring constant depending on the temperature change, so that the change in the spring constant is caused by the viscosity of the oil accompanying the temperature change. By adapting to the change, the oil flow rate can be kept constant regardless of temperature changes.

The flow control valve of the present invention is not limited to the above-mentioned door closer.
It can be applied to various hydraulic equipment and oil distribution devices.

Embodiment FIGS. 1 and 2 show the structure of the flow control valve of the present invention. In these figures, the valve body insertion hole (22) is formed so as to divide the oil passage (21). A spool-shaped control valve body (23) is slidably inserted into this valve body insertion hole (22). Valve insertion hole (2
If one side of the oil passage (21) divided by 2) is an inlet passage (24) and the other side is an outlet passage (25),
The opening area of the inlet passageway (24) that opens into the insertion hole (22) is changed as shown in FIG. 2 by the sliding movement of the valve body (23). That is, due to this change in the open area, the flow rate of oil flowing from the inlet passageway (24) to the outlet passageway (25) side or in the opposite direction is changed. Then, the insertion hole (22
) are fitted with a pair of coil springs (26) (27) M that act on opposite end faces of the valve body (23), and the valve body (23)
26) The forces in (27) are held in a balanced position,
As a result, when the viscosity of the oil is constant, a constant flow rate is always passed through.

And in this example, these springs (26) (
27), the spring (27) on the side where the valve body (23) acts in a direction to close the opening area of the inlet passageway (24),
It is made of a shape memory alloy whose spring constant changes depending on temperature changes.

FIG. 3 shows a graph showing the spring characteristics of the spring (27) made of the shape memory alloy. This graph shows a spring set to have a length β in the high temperature range, and a spring set to have a length E! This figure shows the results of measuring the reaction force F when compressed to the maximum temperature along with the temperature change. As can be seen from this figure, the spring (27) made of a shape memory alloy is designed so that its spring constant increases as its temperature increases.

In this graph, the side indicated by the black circle is when the temperature is rising, and the side indicated by the white circle is when the temperature is decreasing, and there is a slight hysteresis. For those who do not, there is no problem at all.

Therefore, in the structure shown in Fig. 1, the spring constant of the spring (27) made of a shape memory alloy with the above-mentioned characteristics increases as the temperature rises, so the viscosity of the oil decreases as the temperature rises. In this case, the increase in the spring constant moves the valve body (23) in a direction that reduces the open area of the artificial passageway (24), which reduces the oil flow rate and, on the other hand, lowers the temperature. When the viscosity increases due to the decrease in the spring constant, the other spring (26) pushes the oil back toward the right in the figure, increasing the open area of the inlet passage (24) and increasing the flow rate of the oil. . Therefore, when this control valve is used in the oil passage (10) of a door closer, it becomes possible to keep the closing speed of the door almost constant throughout the seasons, eliminating the need for special adjustment.

In Fig. 1, oil pressure is applied to both ends of the valve body (23), so the position of the valve body (23) is between the springs (26) and (27). It is said that it is determined only by balance, but for example,
When the pressure of the oil on the outlet passage (25) side is not applied, the position is determined by the balance between the oil pressure on the outlet side and the spring (26), and the other spring (27). It happens. Further, although the outlet passage (25) is formed on the side of the valve body insertion hole (22), it may be formed to penetrate inside the valve body (23) as shown by the two-dot chain line in the figure. This allows the overall structure to be made smaller.

Effects of the Invention As described above, according to the present invention, even if the viscosity of oil changes in response to temperature changes, the flow rate can be maintained constant by changing the spring constant of the spring made of a shape memory alloy. This has the effect of making it possible to obtain a control valve with a constant flow rate without having to make special flow rate adjustments due to temperature changes.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view of the control valve of the present invention, Fig. 2 is a longitudinal sectional view of the main parts when the opening of the oil inlet passage is viewed from the front, and Fig. 3 is a longitudinal sectional view of the main part of the control valve of the present invention. FIG. 4 is a graph showing the change in spring constant due to temperature change, and FIG. 4 is an external view of a conventional door closer. FIG. 5 is a vertical cross-sectional view of the main body of the door closer. (1)...Door closer body, (21)...Oil passage, (23)...Control valve body, (26) (2
7)...Spring. Patent Applicant Sekisui House Co., Ltd. Agent Patent Attorney Hisayuki Taruki 271 Figure 2 Da Figure 3 OIo 20 30
40 Onji ('C) Procedure Neichi j1311 (voluntary)
(1986/11/J2'; Ro.

Claims (1)

[Scope of Claims] 1. A valve body that moves in a direction that changes the open area of the oil passage, and a pair of spring bodies that act in opposite directions with respect to the moving direction of both valve bodies; An oil flow control valve characterized in that at least one of the spring bodies is made of a shape memory alloy whose spring constant changes according to temperature changes. 2. The oil amount control valve according to claim 1, wherein the oil amount control valve is a closing speed adjusting valve provided in an oil passage connecting both side chambers of the piston of the door closer.