JPH0669499U - Linear motion converter - Google Patents

Abstract

(57) [Abstract] [Purpose] Miniaturize the linear motion converter. [Structure] On one side of pistons 6 and 7 provided on a side of a pinion 5 which is integrated with a drive shaft 4 provided in a cylinder 3,
Protruding rods 8 and 9 are provided which are axially protruded, whose outer peripheral surface abuts on the inner surface of the cylinder 3 and which engages with the pinion 5 and in which racks 10 and 11 are carved, and which are provided at the centers of the pistons 6 and 7, respectively. Guide rods (12, 16) for guiding the shaft in the axial direction are provided.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 TECHNICAL FIELD The present invention relates to an improvement of a linear motion conversion device that obtains a rotational motion by a piston that is linearly reciprocated by fluid pressure.

[0002]

[Prior art]

 For example, in order to rotate the drive shaft of the valve body forward and backward, a pinion that is integrated with the drive shaft is engaged with a rack that is integral with the reciprocating piston provided in the fluid actuated cylinder. Needless to say, it is described in numerous patents and utility model publications, and it is well known or well known to the related engineers.

[0003]

[Problems to be solved by the device]

 In the above device, the pinion is generally formed on the centripetal side of a protruding rod that projects inward from one side of the piston body in the axial direction.

The outer peripheral surface of the rod in the centrifugal direction slides on the inner surface of the cylinder together with the piston, but the rack receives a force that tends to escape in the centrifugal direction due to the reaction caused by the engagement with the pinion. Therefore, if the axial thickness and dimensions of the piston are not sufficiently large, the piston and the rod will tend to tilt with the meshing part with the pinion as the fulcrum, and will locally press the inner surface of the cylinder, Sliding inside is not smooth.

In order to prevent such a fear, it is necessary to make the axial length of the piston or the rod, that is, the length of the sliding portion with the cylinder sufficiently large. The miniaturization of the entire device including the cylinder is restricted.

[0006]

[Means for Solving the Problems]

 According to the present invention, a piston is provided on the side of a pinion which is integral with a drive shaft provided in a cylinder so as to be slidable in the axial direction with an appropriate pressure fluid, and is provided on one side of the piston. A projecting rod is provided, which protrudes in the axial direction, has an outer peripheral surface slidably abutting the inner surface of the cylinder, and is engraved with a rack that meshes with the pinion, and guides it axially in the center of the piston. The above-mentioned problems can be solved by providing the guide rod.

[0007]

[Action]

 Each piston is guided and supported at two places, slides in the sliding direction, and does not tilt.

[0008]

【Example】

 FIG. 1 shows a first embodiment of the present invention. A vertical drive shaft (4) is inserted through the center of a cylinder (3) whose left and right ends are closed by covers (1) and (2), and the center of the cylinder (3) is attached to the upper end of the drive shaft (4). A pinion (5) located on the axis of 3) is integrally provided.

Pistons (6) and (7) are provided in the cylinder (3) on both left and right sides of the pinion (5), and the rear part (the upper part in the drawing) of the left piston (6) and the right piston (7) are provided. At the front part (lower part in the drawing) of the above, there are integrally provided, respectively, projecting rods (8) and (9) projecting inward in the axial direction beyond the pinion (5).

Axial racks (10) and (11), which fit properly with the pinion (5), are engraved on the facing surfaces of the projecting rods (8) and (9), respectively.

An inner end of a guide rod (12) protruding leftward is fixed to the center of the left piston (6), and an outer end of the guide rod (12) is provided at the center of the inner surface of the left cover (1). It is slidably supported in 13).

At the center of the right piston (7), an inner end of a guide rod (15) which has a through hole (14) in the axial direction and which protrudes to the right is fixed, and its outer end is at the right side. It is slidably supported in a receiving cylinder (16) provided at the center of the inner surface of the cover (2).

The left and right covers (1) and (2) and the cylinder (3) are provided with a supply for connecting two spaces of the left and right covers (1) and (2) and the left and right pistons (6) and (7). The vent (18) is open. Compressed air is introduced into the space between the left and right pistons (6) and (7) in the right cover (2) through the inside of the receiving cylinder (16) and the through hole (14) of the guide rod (15). An air supply / exhaust hole (18) for supplying and exhausting air is provided.

Both of the pistons (6) and (7) simultaneously slide in and out by supplying or exhausting pressurized air from any of the air supply / exhaust holes (17) (18), and the racks (10) (11) ), The pinion (5) and the drive shaft (4) are rotated forward and backward.

Since the racks (10) (11) on the centripetal side of the projecting rods (8) (9) which are integral with the pistons (6) (7) mesh with the pinion (5), the pistons (6) ) When sliding (7), the pistons (6) and (7) are acted on by the tilting force centered on the meshing point, but the pistons (6) and (7) are not limited to the inner surface of the cylinder (3). Instead, they are also guided by the guide rods (12) and (15) respectively, so that tilting of the pistons (6) and (7) is prevented. Therefore, as compared with the conventional type, the rods 8 and 9 can operate smoothly and lightly even if the length of the rods 8 and 9 is considerably small.

FIG. 2 shows a second embodiment of the present invention. In the second embodiment, the arrangement of the members designated by the same reference numerals as in the first embodiment is basically the same as in the first embodiment.

The difference is that the outer ends of the left and right guide rods (12) and (15) are fixed to the receiving cylinders (13) and (16) of the left and right covers (1) and (2), respectively. Is to be slidably fitted into the pistons (6) and (7) respectively.

Even in this case, it is obvious that the same effects as those of the first embodiment can be obtained, and there is an advantage that the pistons (6) and (7) can be easily attached and detached.

It goes without saying that the present invention can also be applied to a single-acting motion conversion device in which one stroke of the piston is made by the force of a spring.

[0020]

[Effect of device]

 Since the piston is guided in the axial direction at two points, the inner surface of the cylinder facing the axial direction and the guide rod, its tilting is prevented, and it is possible to operate smoothly without applying excessive force. .

[Brief description of drawings]

FIG. 1 is a plan view showing a first embodiment of the present invention.

FIG. 2 is a plan view showing a second embodiment of the present invention.

[Explanation of symbols]

 (1) (2) Cover (3) Cylinder (4) Drive shaft (5) Pinion (6) (7) Piston (8) (9) Projecting rod (10) (11) Rack (12) Guide rod (13) Receptacle (14) Through hole (15) Guide rod (16) Receptacle (17) (18) Air supply / exhaust hole

[Procedure amendment]

[Submission date] April 14, 1994

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 1

[Correction method] Change

[Correction content]

[Figure 1]

Claims (5)

[Scope of utility model registration request] 1. A piston is provided on a side of a pinion that is integral with a drive shaft provided in a cylinder so as to be slidable in an axial direction with an appropriate pressure fluid, and on one side of the piston. A projection rod is provided, which protrudes in the axial direction, has an outer peripheral surface slidably abutting the inner surface of the cylinder, and which is engraved with a rack that meshes with the pinion, and further guides this in the axial direction to the center of the piston. A linear motion conversion device provided with a guide rod. 2. The linear motion conversion device according to claim 1, wherein an inner end of the guide rod is fixed to the piston, and an outer end of the guide rod is slidably fitted into an end cover of the cylinder. 3. The linear motion conversion device according to claim 1, wherein an inner end of the guide rod is slidably fitted into the piston, and an outer end thereof is fixed to a side end cover of the cylinder. 4. The linear motion conversion device according to claim 1, wherein the piston is a reciprocating type in which the pressure of the pressure fluid can be applied to both sides of the piston. 5. The linear motion conversion device according to claim 1, wherein the piston is a single-acting type in which a pressure fluid can be applied to one side thereof and a spring is biased in the opposite direction. .