JPH051820Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Objective of the Invention] (Field of Industrial Application) The present invention relates to a hydraulic rotational speed detection device, and particularly to a governor valve for an automatic transmission for an automobile.

(Prior art) A governor valve is attached to the output shaft of an automatic transmission in order to extract the vehicle speed signal as hydraulic pressure for shift control of the automatic transmission, and outputs hydraulic pressure corresponding to the centrifugal force acting on the governor weight. It is something to do.

A conventional example of this type is one shown in FIG. 3, for example. This is a governor valve device that obtains two-stage hydraulic characteristics, and provides a hydraulic pressure (governor pressure) proportional to the square of the rotation speed of the output shaft. When the output shaft 4 is rotating in the governor valve device 21, centrifugal force acts on the governor weight 2, and the bottom surface 7 of the governor weight 2 and the governor body 3
are separated from the outer end surface 5 of. When the rotation of the output shaft 4 stops, the action of centrifugal force disappears, and the two surfaces come into contact.

(Problem to be solved by the invention) In the conventional device, when the bottom surface of the governor weight and the outer end surface of the governor body come into contact when the rotation of the output shaft stops, as shown in FIG. The bottom surface 7 of the governor weight 2 comes into contact with the burr 20 formed at the outer edge of the center hole 6 of 3 (FIG. 4A), and this burr 20 is bent inward (FIG. 4B). This burr 20 is a sharp point formed at the outer edge during machining of the body center hole 6, and has a size of several microns.
This inwardly bent burr 20 slows down the movement of the valve element 1 in the centrifugal direction, and as shown in FIG. This had the disadvantage of causing poor pressure regulation. Chamfering the outer edge of the center hole of the governor body for the purpose of removing burrs can cause foreign objects to become trapped, and when foreign objects become trapped, the movement of the governor valve becomes sluggish, resulting in poor pressure regulation as described above. invite. In addition, in order to avoid contact between the bottom surface of the governor weight and the outer end surface of the governor body, the governor weight is fixed to the governor shaft, and the governor shaft is brought into contact with the output shaft to restrict movement of the governor weight in the inward direction. This method can also be considered. However, in this case, when the governor shaft comes into contact with the output shaft during rotation, friction occurs between the output shaft and the governor shaft, and as a result, abrasion powder is generated. If this abrasion powder adheres to the sliding surface of the governor valve, it will adversely affect the movement of the valve. Further, as wear progresses, the governor weight will eventually come into contact with the governor body, leading to the aforementioned governor pressure regulation failure.

The technical object of the present invention is to provide a novel fluid-type rotational speed detection device that solves the above-mentioned problems and eliminates the influence of burrs.

[Structure of the idea]

(Means for solving the problem) The technical means taken to achieve the above technical problem is to provide a circumferential stepped groove on the edge of the weight that contacts the outer end of the body center hole. It is.

(Function) With the above technical means, the burrs occur on the inner circumference of the stepped groove, and the burrs occur toward the inside of the groove.
It does not come into contact with the bottom surface of the governor weight and does not act on the valve element.

(Example) Hereinafter, an example of the present invention will be described based on drawings in which a governor valve is implemented. In FIGS. 1 and 2, a circumferential stepped groove 8 is provided at the outer edge of the center hole 6 of the body 30. As shown in FIGS. The governor body 3' fixed to the output shaft 4 has a center hole 6 opening in the centrifugal direction,
Inlet port 11, output port 1 in the direction perpendicular to the centrifugal direction
2 and a discharge port 13. The valve element 1 is slidably fitted into this central hole 6 and is actuated by centrifugal force. A governor valve shaft 14 is fitted within the valve element 1 and slides in the centrifugal direction on the inner circumferential surface of the valve element 1 and the inner circumferential surface of the governor body 3'. Governor valve shaft 14
A governor weight 2 is attached to the outer end of the governor weight 2, and its movement in the centrifugal direction is regulated by a snap spring 15. A spring 16 is attached to the gap between the outer peripheral surface of the governor valve shaft 14 and the inner peripheral surface of the valve element 1.

In the above configuration, pressure oil is supplied to the inlet 11 from the oil pump. When the output shaft 4 rotates at a low speed, the governor weight 2, the governor valve shaft 14, the valve element 1, and the spring 16 move together, and the centrifugal force acting on the governor weight 2, the governor valve shaft 14, and the valve element 1 is The hydraulic pressure in which the centripetal forces applied to the valve element 1 are balanced is outputted from the output port 12 as the governor pressure at that vehicle speed, and one step of pressure regulation is performed. When the rotational speed of the output shaft 4 further increases and the speed becomes high, the flange 18 of the governor valve shaft 14 moves to the end surface 1 of the governor body.
7, the movement of the governor valve shaft 14 is stopped by the governor body 3', and from then on, hydraulic pressure in which the centrifugal force of the valve element 1 and the reaction force of the spring 16 are balanced is outputted from the output port 12.

When the output shaft is rotating, the outer end surface 21 of the valve element 1 projects beyond the outer end surface 5 of the governor body, and the bottom surface 7 of the governor weight leaves this outer end surface 5.
When the output shaft stops rotating, the governor weight 2 and the valve element 1 move centrially, and the outer end surfaces 21 and 5 of the valve element 1 and the governor body 3' come into contact with the bottom surface 7 of the governor weight 2. At this time, the burr 20 formed inside the stepped groove 8 of the center hole 6 of the governor body escapes into the stepped groove 8, so that the burr 20
0 is avoided, and as a result, the phenomenon of the burr 20 being directed toward the inner peripheral side of the governor body 3 is eliminated.

[Effect of idea]

As described above, the fluid rotational speed detection device of the present invention has a simple structure and processing in which a stepped groove is provided all around the outer edge of the center hole of the governor body, eliminating the influence of burrs. A centrifugal movement of the weight can be obtained that accurately responds to changes in the rotational speed of the rotating shaft. Therefore, accurate movement of the weight based on the rotational speed can be replaced with hydraulic pressure proportional to the rotational speed, and appropriate hydraulic characteristics can be obtained.

[Brief explanation of drawings]

Fig. 1 is an embodiment of the present invention, Fig. 2 is an enlarged partial sectional view of the part shown in Fig. 1, Fig. 3 is a sectional view of a conventional governor valve device, and Fig. 4A is a partial sectional view of the part shown in Fig. 3. FIG. 4B is an enlarged view of the part shown in FIG. 3 before bending the burr, FIG. 4B is an enlarged partial sectional view of the portion shown in FIG. 1...Valve element, 2...Governor weight, 3,
3'... Governor body, 4... Output shaft, 8... Circumferential stepped groove, 20... Burr.

Claims (1)

[Scope of utility model registration request] A fluid having a body that rotates in conjunction with a rotating shaft, a weight that moves in a centrifugal direction from the rotating shaft, and a valve element that is arranged in a center hole of the body so as to be slidable in a centrifugal direction in relation to the weight. What is claimed is: 1. A fluid-type rotational speed detection device, characterized in that a circumferential stepped groove is provided at the outer end of the body center hole in contact with the weight.