JPS62288754A - Rotating speed change gear - Google Patents

Abstract

PURPOSE:To reduce the generation of heat and simplify the construction of a rotating speed change gear by rotatably supporting an intermediate gear to an idler shaft whose both ends are oppositely placed and connecting a pressure fluid supplying source to respective cylinders through direction change-over values. CONSTITUTION:Pressure fluid is supplied or discharged from respective stationary cylinders 24, 25 through direction change-over valves 41, 42 to move an idler shaft 32 in the axial direction, and engagement of an intermediate gear 31 rotatably supported by the idler shaft with a drive gear 11 and a driven gear 22 is changed to change the rotating speed of a main shaft 21. That is, the intermediate gear 31 is only rotated to the idler shaft 32 through a bearing 35 and heat is little generated. And cylinders 24, 25 slidably retaining the idler shaft are provided on both ends of the shaft, therefore construction can be made simpler.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Object of the Invention] (Industrial Field of Application) The present invention is arranged between a rotational drive source and a rotated body, and provides rotational drive to the rotated body. The present invention relates to a rotational speed changing device that can transmit rotational force from a source and change the rotational speed of a rotated body.

(Prior art) As a device for changing the rotational speed of a rotated object, such as a 5A setting that changes the rotational speed of a main shaft in a work area, a plurality of parallel plates are used between a driving gear and a driven fJl gear. A device is used in which an intermediate gear formed by a combination of gears is interposed, and the intermediate gear is moved in the direction of the rotation axis to change the meshing ratio of each gear to change the rotation speed.

In a rotational speed changing device using such a gear train,
The intermediate gear is movably attached to the rotatably supported intermediate shaft by being guided by a sliding key, etc., and a guide plate is inserted into a groove provided around the outer edge of the intermediate gear so as to be perpendicular to the rotating shaft. The guide plate can be moved in the axial direction by inserting the guide plate from the direction of the guide plate and semi-retracting the guide plate in the direction of the rotation axis using a hydraulic cylinder.

(Problems to be Solved by the Invention) In the above-mentioned conventional rotational speed transmission device, when the intermediate tooth width is rotating, it is necessary to prevent metal contact between the groove and the guide plate inserted into the groove. , it is necessary to spray a large amount of lubricating oil into the gap between the groove and the guide plate. However, even so, heat generation in this gap is unavoidable, and there is a problem in that it adversely affects thermal accuracy, especially when rotating at high speed. In addition, a hydraulic cylinder for driving the guide plate had to be specially installed, which made the M4 construction complicated and the assembly work troublesome.

The present invention has been made in consideration of these points,
It is an object of the present invention to provide a rotational speed changing device that generates less heat and can be simplified in structure.

[Structure of the invention]

(Means for Solving the Problems) The present invention provides a driving gear, a driven gear, and an intermediate gear, each of which is formed by consecutively connecting a plurality of spur gears each having a different number of teeth. A device that is disposed so as to be able to mesh with gears at the same time, and changes the meshing position of each gear by moving the intermediate gear in the direction of the rotation axis, and changes the rotational speed of the driven gear, the intermediate gear comprising: Both ends are rotatably supported by an idler shaft that is inserted into and held in two cylinders facing each other, and pressurized fluid is supplied to each cylinder via a directional control valve. The feature is that the source is connected.

(Function) According to the present invention, by supplying or discharging pressure fluid into each fixed cylinder through a directional control valve, the idler shaft is moved in the axial direction, and the intermediate gear rotatably supported by the idler shaft is moved. The rotational speed can be changed by changing the meshing state between the driving gear and the driven gear.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

The figure is a sectional view showing an example in which the rotational speed changing device according to the present invention is used as a rotating speed changing device for the main shaft of a machine tool. In the figure, reference numeral 11 indicates a drive width m that provides rotational driving force, and is constructed by connecting a large spur gear 11a and a small spur gear 11b having different numbers of teeth along a rotating shaft 12. Rotating axis 1
2 is supported at both ends by bearings 13 and connected to a rotational drive source, for example, an electric motor 14.

Reference numeral 21 is the main shaft of the machine tool, and a driven gear 22 is li! with respect to this main shaft 21. I! It is worn. The driven gear 22 is a Taihei #i gear having a large number of teeth arranged in series in the direction of the main shaft axis.
It is composed of an i-tun 22a and a small spur gear 22b with a small number of teeth.

An intermediate tooth width 31 is disposed between the drive gear width 11 and the driven gear 22, and by meshing with the drive gear 11 and the driven gear 22 at the same time, the rotational driving force of the drive gear 11 is reduced. can be transmitted to the test subject fJJ 1!6 ¥122. The intermediate gear 31 is constructed by consecutively arranging three spur gears having different numbers of teeth, that is, a large spur gear 31a, a medium spur gear 31b, and a small spur gear 31c. The number of teeth and the axial arrangement position of these three spur gears are determined by the number of teeth and the arrangement position of the large and small spur gears of the driving gear 11 and the driven gear 22 with which they mesh.

Drive gear 11. The driven gear 22 and the intermediate gear 31 are
The main shaft 21 is disposed in a spindle head 23 that is rotatably held, and cylinders 24 that are open toward the inside of the spindle head are provided in the spindle head 23 at positions facing each other with an intermediate tooth width 31 in between. .25 is installed. This cylinder 24.
Both ends 33 and 34 of the idler shaft 32 are inserted into the shaft 25 so as to be slidable in the axial direction, thereby forming a hydraulic screw cylinder mechanism. An intermediate gear 31 is rotatably supported at the center of the idler shaft 32 via a bearing 35.

One end 34 of the idler shaft 32 has a large diameter portion 34a.
A small diameter portion 34b is formed in the cylinder 25, and a small diameter cylinder chamber 25b and a large diameter cylinder chamber 25a are formed in the cylinder 25. A float piston 36 that slides within the cylinder chamber 25b is loosely fitted into the narrow diameter portion 34b. The outer diameter of the float piston 36 is made larger than the outer diameters of the end portion 33 and the large diameter portion 34a, and connects the cylinder 25 that slides and supports the large diameter portion 34a with the cylinder chamber 25b in which the float piston 36 slides. Cylinder chamber 25 in the communicating part
G is installed -1.

An oil boat 26 and an oil boat 27 are bored in the innermost part of the cylinder 24 and near the cylinder chamber 25c of the cylinder 25 to supply pressure oil to the cylinder chamber 24a and the cylinder chamber 25c, respectively. is connected via a directional valve 41 to a pressure fluid supply source (not shown). Further, an oil boat 28 for supplying pressure oil to the cylinder chamber 25b is bored in the innermost part of the cylinder 25, and this oil boat 28 is connected to a pressure fluid supply source (not shown) via a directional control valve 42. It is done (-).

Next, Kinohi hI which consists of such a structure! Let me explain about the example of sex.

The figure shows a medium speed rotation state, and the small spur gear 11b of the driving tooth 11 and the small spur gear 22b of the driven tooth width 22 are connected via the large spur gear 31a of the intermediate gear 31.

In this case, cylinder chamber 24a and cylinder chamber: 25t
) are supplied with pressure oil through oil boats 26 and 28, respectively, and no pressure oil is supplied to the cylinder chamber 25c.

Therefore, the end portion 33 of the idler shaft 32 is pushed rightward in the drawing, and the float piston 36 is pushed in the direction htJ in the drawing, moving to the step 125C and stopping.

To shift from this state to low speed operation, the directional control valve 41
．． 42 is activated to open the cylinder chamber 24a.

25b is discharged, and pressure oil is supplied from the Ura boat 27 to the cylinder chamber 25c. As a result, the float piston 36 first moves to the 41 end of the cylinder 25 (moves to the right in the drawing), and then the large diameter portion 34a is pushed to the left in the drawing by the pressure oil, and the end 33 of the idler shaft 32 Move to the innermost end of the cylinder 24. The intermediate gear 31 moves to the left in the drawing together with the idler shaft 32, and its large spur gear 31a meshes with the small spur gear 11b of the driving tooth Tltl11, and the small spur gear 31c meshes with the large spur gear 22a of the test e gear 22. . As a result, the rotational force of the drive gear 11 is transmitted from the small spur gear 11b to the large spur gear 22a of the driven gear 22 via the intermediate gear 31, allowing the main shaft 21 to operate at a low speed.

On the other hand, in order to shift from medium speed operation to high speed operation, pressurized oil is supplied to the cylinder chamber 24a, and the cylinder chambers 25b, 25C
Drain the pressure oil from. The idler @32 is moved further to the right than the state shown in the figure, and the large spur tooth Φ of the drive tooth width 11
11a and the intermediate gear 31b of the intermediate gear 31 mesh with each other, and the medium large spur gear 318 of the intermediate gear 31 and the small spur gear 22b of the driven gear 22 simultaneously mesh with each other, resulting in high-speed operation of the main @21.

As described above, according to this embodiment, the idler shaft 32 on which the intermediate gear 31 is rotatably supported is reciprocated in the axial direction using the hydraulic piston/cylinder mechanism provided at both ends of the idler shaft 32, so that the drive tooth width 11 and the idler shaft 32 are By changing the meshing relationship with the drive tooth width 22, the rotational speed can be changed. In addition, the idler shaft 3
2, a float piston 36 is fitted with Ti on one end of the
By moving this float piston 3G toward the other side of the idler shaft 32, the idler shaft 32 can be stopped at an intermediate position, in this embodiment, a medium speed rotation state.

According to this embodiment, the intermediate gear 31 only rotates with respect to the idler shaft 32 via the bearing 35, and unlike the conventional gear, there is no part where metal friction may occur during rotation.

Therefore, it is not necessary to inject a large amount of lubricating oil to prevent the generation of frictional heat as in the conventional case, and the heat generation a can be extremely reduced. Furthermore Idler @32
It is only necessary to provide cylinders 24 and 25 to slide and hold the guide plate at both ends of the guide plate, and there is no need to provide a guide plate or a hydraulic cylinder for driving the guide plate as in the conventional case.The structure is simple and the assembly work is easy. It is.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to provide a rotational speed changing device which is not affected by heat, has no heat generating parts, has a simple structure, and is easy to assemble.

The present invention is not limited to a rotational speed changing device for a main shaft of a machine tool, but can be widely applied to a gear type rotational speed changing device that changes the rotational speed by shifting an intermediate gear.

[Brief explanation of drawings]

The drawing is a sectional view showing an example in which the rotational speed changing device according to the present invention is applied to the main shaft of a machine tool. 11... Drive gear, 21... Main shaft, 22... Driven gear, 24.25... Cylinder, 26, 27.28
... Oil boat, 31 ... Intermediate gear, 32 ... Idler shaft, 33. 34 ... End of idler shaft, 36 ...
・Float piston. Procedural Amendment 4 8 July 25, 1986 (1) Mr. Akio Kuroda of the Japan Patent Office ``Rotational speed transmission device'' Stone 3 Person making the amendment Effect a
Relationship to the case Patent applicant (5) (3
45) Toshiba Machinery Co., Ltd. "1 Drawing. "Oil lubricant" in line 12 of page 3 of the specification of amendment is corrected to read "1 lubricant." [Cylinder chamber 25a and] on page 7, line 5 to line 6 of the specification are deleted. "Outer diameter" on page 7, line 9 of the specification is corrected to "effective 1". "Outer diameter" on page 3, line 10 of the specification is corrected to "i product." Correct ``oil oil'' in line 17 of page 10 of the Meiji to read ``1 oil''.

Claims (1)

[Claims] 1. A driving gear, a driven gear, and an intermediate gear each having a plurality of spur gears each having a different number of teeth, the intermediate gear meshing with the driving gear and the driven gear at the same time. In the device for changing the meshing position of each gear by moving the intermediate gear in the direction of the rotation axis and changing the rotational speed of the driven gear, the intermediate gear
Both ends are rotatably supported by an idler shaft that is slidably inserted and held in two cylinders arranged opposite each other, and each cylinder is supplied with pressurized fluid via a directional control valve. A rotational speed variable transmission device, characterized in that a supply source is connected. 2. A patent claim characterized in that one end of the idler shaft is formed with a large diameter part and a small diameter part, and a float piston that slides inside a fixed cylinder is loosely fitted into the small diameter part. The rotational speed changing device according to item 1.