JPS61278606A - Mechanism for changing direction of movement - Google Patents

Abstract

PURPOSE:To realize accurate setting of an angle of rotation of a rotary shaft by forming stopper parts on both sides of the rotary shaft and forming a cam groove between these stopper parts and further fitting said groove to a sliding member through a seal member. CONSTITUTION:Flat stopper parts 7, 8 are formed on both sides of a rotary shaft 4 and a spiral cam groove 9, which has the bottom part of the same shape in the direction perpendicular to the shaft as those of the stoppers 7, 8, is continuously formed between the stoppers 7, 8, while the cam groove 9 is fitted in a sliding member 10 through a seal member 18. Thus, an angle of rotation of the rotary shaft 4 comes to be gradually increased, constant and gradually decreased during process of its rotation from starting to finishing. Therefore, its rotational condition grows smooth and unnecessarily strong force is prevented from being applied on the rotary shaft at times of starting and finishing of rotation. Accordingly, the angle of rotation of the rotary shaft 4 can be accurately set without using the stopper separately.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a mechanism for rotating a rotating shaft by a sliding member that moves in a linear direction, and particularly to an improved power transmission structure between the sliding member and the rotating shaft. This invention relates to a motion direction changing mechanism that includes

[Conventional Technique vi] For example, in an industrial machinery factory, parts that have undergone predetermined processing are transported to the next processing step using a transport device. This transfer device is equipped with a motion direction conversion mechanism that converts the linear movement of the sliding member into rotational movement of the rotating shaft, and as the rotating shaft rotates, the arm attached to this moves the component to a predetermined position. That's what I do.

Conventionally, this motion direction changing mechanism has been used as shown in Fig. 8 or 9.
The one shown in the figure is known. The one in FIG. 8 transmits the reciprocating linear movement of the piston b1 in the cylinder a1 to the pinion d1 via the rack C1, and
This configuration rotates a rotating shaft e1 attached to the rotary shaft e1.

The one in FIG. 9 is a mechanism using a screw-shaped cam. That is, in this FIG. 9, a is the cylinder, and b is the cylinder a.
C is a threaded cam groove formed in the rotating shaft; d is a cylindrical sliding member that moves within the cylinder A; one end of this is engaged with the cam groove C; The other end has an annular portion f into which a rotating shaft is slidably fitted, and as the sliding member d moves, the cam portion e causes the cam groove C to move.
The rotating shaft is rotated through the shaft.

[Problems to be Solved by the Invention] However, all of the above-mentioned methods have room for improvement in the following points.

(1) As the rack C1 or the sliding member d moves at a constant speed, the rotation axis e1 or the rotation axis rotates at a constant speed, so its inertia becomes large at the start and end of rotation, so the arm that transfers the parts Unnecessary force is applied to the

(2) Play such as backlash inevitably occurs between rack C1 and pinion d1 or between cam groove C and cam part e, making it difficult to set an accurate rotation angle and requiring a separate stopper. becomes.

(3) The one in Figure 8 is longer in the axial direction due to the unique properties of the slide C1 and the pinion d1, and the one in Figure 9 has a cam groove C.
Since it is difficult to seal the cam part e, the sliding member d has to have a cylindrical shape and is elongated in the axial direction, increasing the size of the entire device.

The present invention has been made to eliminate the above-mentioned problems, and its purpose is to accelerate and decelerate the rotation wheel at the start and end of rotation, so that unnecessary force is not applied to the arm, and it is possible to use a separate stopper. To provide a movement direction conversion mechanism which can accurately set the rotation angle of a rotation axis without any problems and can downsize the entire device.

[Means for Solving the Problems] The present invention has the following constituent features. (a) a cylinder having first and second ports for a working fluid;
b) A circular rotating shaft disposed inside this cylinder, and (
c) a flat stopper portion formed on both sides of the rotating shaft; and (d) a flat stopper portion formed on the rotating shaft with the same width dimension continuously from one side to the other, and having a shape in the direction perpendicular to the axis. (e) a helical cam groove having the same bottom surface as that of the stopper part; a sliding member that slides back and forth and has an opening through which the rotating shaft is inserted; (f) provided in the opening of the sliding member and elastically in line contact with the stopper portion of the rotating shaft and the cam groove; a sealing member; and (0) a cam member fixed to the sliding member and slidingly contacting a stopper portion of the rotating shaft and a bottom surface of the cam groove to rotationally drive the rotating shaft as the sliding member moves. .

[Operation] When the sliding member moves, the rotational speed of the rotating shaft gradually increases, becomes constant, and gradually decreases depending on the sliding state of the cam part with respect to the stopper part of the rotating shaft, the cam groove, and the stopper part, and the seal The member slides in the stopper portion, the cam groove, and the stopper portion in a sealed manner.

[Embodiment] An embodiment of the present invention will be described below with reference to FIGS. 1 to 7. 1 is a cylinder, and 2 and 3 are end plates sealed at both ends of the cylinder 1. These end plates have pivot holes 2a and 3a in the center, and a hole communicating with the inside of the cylinder 1 on the outer periphery. First and second ports 2b13b
is formed. 4 is a circular rotating shaft, each end of which is fitted with a bearing 5.6 in the shaft support hole 2a, 3a of the end plate 2.3.
is supported through. 7.7 and 8.8 are a pair of stopper parts provided in the cylinder 1 of the rotary shaft 4 in a position close to the end plate 2.3, respectively, and these are made by partially cutting the surface of the rotary shaft 4. By doing so, it is formed to form a flat surface. Reference numeral 9 denotes a two-striped spiral cam groove, which extends continuously from one stopper part 7 to the other stopper part 8 on the rotating shaft 4 with the same width dimension as shown in FIGS. 2 to 4. It is formed. In this case, the shape of the bottom surface of the cam groove 9 in the direction perpendicular to the axis forms a straight line that coincides with that of the flat stopper portion 7.8.

Specifically, the cam 1lI9 of the rotating shaft 4 is manufactured by the following machining process. That is, cutting is performed with an end mill that is moved in the axial direction of the rotary shaft and abutted in the direction perpendicular to the shaft while rotating the rotary shaft around the shaft.

Now, 10 is a disc-shaped sliding member, which is installed in the cylinder 1 so as to be able to reciprocate in the axial direction, and has an opening 11 in the center through which the rotating shaft 4 is inserted, and an annular sliding member in the outer peripheral end. The rubber seal 12 makes elastic contact with the inner circumferential surface of the cylinder 1 in a sealed manner. 13 and 14 are sliding holes, which are formed in the sliding member 10 to face each other with the opening 11 in between. Guide rods 15 and 16, which are provided parallel to the rotating shaft 4, are inserted through these sliding holes 13 and 14 through rubber seals 17, respectively. Reference numeral 18 denotes an annular sealing member provided in the opening 11 of the sliding member 10, which is formed into an annular shape from an elastic material such as rubber, and has a cam groove 9 at its inner circumferential end as shown in FIG. It has a pair of sealing folds 188, 18a that are in line contact with the bottom surface. 19
．． Reference numeral 19 denotes a pair of rectangular cam members made of a highly rigid material such as metal, which has an elongated hole 20 approximately in the center, and a stopper portion 7.8 and a cam groove 9 on the side.
An arcuate chamfered portion 19a that is in line contact with the bottom surface of the
Equipped with This cam member 19 is attached to the elongated hole 2 by a bolt 21.
It is fastened to the sliding member 10 via 0. Therefore, by loosening the bolt 21, the cam member 19 can be moved into the elongated hole 2.
Since the cam member 19 can be moved within a length range of 0, it can be adjusted so that the cam member 19 reliably abuts against the stopper portion 7.8 or the bottom surface of the cam groove 9.

Now, in the above configuration, when a working fluid such as oil is supplied into the cylinder 1 from the second port 3b in the state shown in FIG. 2, the sliding member 1G is pressed by the working fluid and moves at a predetermined speed in the direction of the arrow. Sliding. Along with this, the cam member 19 sequentially slides its chamfered portion 19a onto the stopper portion 8 of the rotating shaft 4, the bottom surface portion of the cam groove 9, and the stopper portion 7, while the seal member 18 slides the seal fold 18a in the same manner as described above. The stopper portion 8, the cam W49, and the stopper portion 7 slide in this order in a liquid-tight state. In this process, the rotating shaft 4 is rotated in a predetermined direction by the cam member 19, and an arm (not shown) attached to the rotating shaft 4 transfers the parts. After that, the working fluid is supplied to the -th port 2.
When supplied into the cylinder 1 from b, the sliding member 10 slides in the direction opposite to the arrow, and the cam member 19 and seal member 18 respectively close the stopper part 7, cam groove 9, and stopper part 8 in the reverse order. Sliding.

In this process, the rotating shaft 4 is rotated by the cam member 19 in the opposite direction to that described above, and the arm returns to its original position.

Incidentally, FIG. 6 shows the lead cam curve set based on the predetermined lead angle of the cam groove 9 for the above-mentioned embodiment.
This figure shows the speed characteristic curve and torque characteristic curve of . According to this, when the cam member 19 slides with respect to the stopper part 8 of the rotary shaft 4, the rotational speed of the rotary shaft 4 is zero and the rotation thereof is prohibited and is in a locked state, and the boundary between the stopper part 8 and the cam groove 9 For convenience, when the cam member 19 slides against the cam member 19, the rotational speed of the rotary shaft 4 gradually increases, and the torque thereof gradually decreases, as shown by a section S for convenience. Further, when the cam member 19 slides in the cam groove 9, the rotational speed and torque of the rotating shaft 4 are both constant as shown by the section opening. Then, when the cam member 19 slides on the boundary between the cam groove 9 and the stopper portion 7, the rotational speed of the rotary shaft 4 gradually decreases as shown in section E, and conversely, the torque gradually increases. When the cam member 19 slides against the stopper portion 7, the rotational speed of the rotating shaft 4 becomes zero, and the rotating shaft 4 enters a locked state in which rotation is prohibited.

In this way, as the sliding member 10 slides, the rotating shaft 4 gradually increases its speed at the start of rotation, then maintains a constant speed and gradually decreases at the end of rotation. Unlike the conventional method, no unnecessary large force is applied to the arm that transfers the parts, and there is no need to install a vibrating member. Moreover, since the cam member 19 is always in sliding contact with the stopper portion 7.8 and the cam groove 9, there is no play such as backlash, which is different from the conventional one, and therefore there is no need to provide a separate stopper. The rotation angle range can be set accurately. In addition, the stopper portion 7.8 and the cam groove 9
Since the bottom surface of the slide member 10 is linear in the direction perpendicular to the axis, the seal member 18 can ensure a fluid-tight state of the sliding member 10 with respect to the stopper portion 7.8 and the cam groove 9. Therefore, it becomes unnecessary to use a cylindrical sliding member d as in the conventional case, and it is possible to shorten the length in the axial direction, thereby reducing the overall size.

In the above embodiment, the guide rods 15 and 16 were used to prevent the sliding member 10 from rotating, but only one of these may be used and the other may be omitted. In this case, the rotating shaft may be mounted eccentrically and the rotating shaft itself may also function as a guide rod. Furthermore, the cam groove 9 is not only a double spiral;
- It may be formed by a spiral with multiple threads such as three threads, three threads, and four threads. In this case, a rotating shaft with a single cam groove is shown in FIG.

[Effects of the Invention] As described above, according to the present invention, since the rotating shaft gradually increases, remains constant, and gradually decreases during the process from the start to the end of its rotation, the rotating state becomes smooth, and This prevents unnecessary large force from being applied to the rotating shaft at the start and end of rotation, and furthermore, the rotation angle of the rotating shaft can be set accurately without using a separate stopper, and it also contributes to overall miniaturization. A mechanism for changing the direction of sipping motion can be provided.

[Brief explanation of the drawing]

1 to 6 show an embodiment of the present invention, in which FIG. 1 is a lateral view of the motion direction conversion mechanism, FIG. 2 is a longitudinal sectional view of the same mechanism, and FIG. 3 is a plane of the rotation axis. 4 is a perspective view of the rotating shaft, and FIG. 5 is a plan view of the sealing member shown together with a sectional view.
FIG. 6 is a graph showing a lead cam curve, a speed characteristic curve, and a torque characteristic curve, FIG. 7 is a perspective view showing a rotating shaft of another embodiment of the present invention, and FIGS. 8 and 9 are both graphs. FIG. 2 is a longitudinal cross-sectional view showing a conventional motion direction conversion mechanism. In the figure 1...Cylinder 2b, 3b...First,
Second port 4...Rotating shaft 7.8...Stopper part 9...Cam groove 10...Sliding member 11...
Opening 18... Seal member 19... Cam member

Claims (1)

[Claims] (a) a cylinder having first and second ports for a working fluid; (b) a circular rotating shaft disposed within the cylinder; (c) a circular rotating shaft disposed within the cylinder; (d) a flat stopper part formed on both sides; (d) a flat stopper part formed continuously on the rotating shaft from one side of the stopper part to the other with the same width dimension, and whose shape in the direction perpendicular to the axis is the same as that of the stopper part; (e) a spiral cam groove having a bottom surface portion; a sliding member having an opening through which the shaft is inserted; (f) a sealing member provided in the opening of the sliding member and elastically in line contact with the stopper portion and the cam groove of the rotating shaft; (g) A motion direction changing mechanism comprising: a cam member fixed to the sliding member, slidingly in contact with a stopper portion of the rotating shaft and a bottom surface of a cam groove, and rotationally driving the rotating shaft as the sliding member moves.