JPH0578702B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention converts rotational motion into linear reciprocating motion,
The present invention relates to a linear reciprocating device that can adjust the stepless change in stroke amount.

[Conventional technology]

Conventionally, a double eccentric machine as shown in FIGS. 4 and 5, for example, has been used as a device for converting rotational motion into linear reciprocating motion.

This linear reciprocating device 21 has an internal gear 24 fixed to the inside of a housing 22 by machine screws 24n, and an external gear portion that has half the number of teeth of the internal gear 24 and meshes with the internal gear 24. A drive block 25 with a weight of 25 g is assembled. Note that the ratio of the diameters D and d of pitch circles 24p and 25p between the internal gear 24 and the external gear portion 25g is 2:1. (See Fig. 6) The drive block 25 has an external gear portion 25g on the rear surface.
A rotatable shaft portion 28j is eccentrically supported with an eccentric amount H on the input shaft 23 which is directly connected and fixed to the rotating shaft of the motor (not shown), and a rotatable shaft portion 28j is provided protrudingly from the front surface. Drive arm portion 2 formed in portion 25h
5k will be added. Note that the amount of eccentricity between the external gear portion 25g and the eccentric drive shaft portion 25h is the same value as the amount of eccentricity H described above. In addition, the external gear part 25g
The external gear is fixed to the main body of the drive block 25 with a key.

The eccentric drive shaft portion 25h is connected to a passive ring 26U of the reciprocating block 26 via a bearing 26b. Note that FIG. 4 shows a state in which the piston pump 40 is installed on one side.

This reciprocating block 26 is connected to the passive ring 26U.
A pair of sliding rods 29S are butted against each other on both outer sides of the housing 22, and a pair of sliding rods 29S are connected to each other.
is supported and can reciprocate in the lateral direction.
The center line 26S _c of the sliding rod 26S is always perpendicular to the center line 23c of the input shaft 23 at point C.

Next, the operation of the drive block having the above configuration will be explained with reference to a schematic front view of the main parts in FIG.

Now, as shown in the same figure, in order to assemble the reciprocating block 26 to the drive block 25 meshing with the internal gear 24, it must be mounted on a plane F perpendicular to the center line _26Sc of the reciprocating block 26 at point C. Position the center line 25g _c of the external gear part 25g and the center line 25h _c of the eccentric drive shaft part 25h (in this case, the center line 25g
5h _c coincides with point C), the eccentric drive shaft portion 25
The reciprocating block 26 is assembled by fitting the passive ring 26U onto h.
Set. This state is set as a reference posture, and the vehicle is started from this posture.

Therefore, when the input shaft 23 is rotated in the direction of arrow M, as shown in the figure, the external gear portion 25g is rotated in conjunction with this in the direction of arrow N, and its center line 2
5g _c is centered at point C and has radius H (=d/2=D/4)
While moving in the direction of arrow M along the circumference E (see the same figure), the center line 25 of the eccentric drive shaft portion 25h
Since h _c , that is, the center line 26 U _c of the driven ring 26 U moves in the direction of arrow L along the center line 26 S _c , the reciprocating block 26 is moved in the same direction. Subsequently, as shown in the figure, when the center line 25g _c intersects the center line 26S _c , the center line 26U _c intersects with the center line 26S _c , which is opposite to the pitch circle 24p of the internal gear 24. Matches point a. As the rotation of the external gear portion 25g further progresses, the center line 26U _c turns back and advances in the direction of the arrow R, passes through point C and coincides with point b of the center line 26S _c facing the pitch circle 24p on the right. As the rotation of the external gear portion 25g further progresses, the center line 26U _c returns, and when the center line 25g _c returns to the reference posture that coincides with the plane F, the center line 26U _c also returns to point C, and the reciprocating block 26 The two-stroke operation is completed.

That is, one revolution of the input shaft 23 causes the reciprocating block 26 to make one reciprocation, and the stroke amount in this case is the distance between points a and b, that is, the diameter D (=4H) of the internal gear 24. .

[Problem to be solved by the invention]

In conventional linear reciprocating devices, the stroke of the reciprocating block is the pitch diameter of the internal gear (4 times the eccentricity), and is limited to this, so in order to change the stroke, the internal gear, drive It is necessary to convert components such as the block and input shaft to ones with different dimensions, and the error in eccentricity between each center line becomes 4 times the stroke error after assembly. The amounts must be perfectly matched through precision machining; if they do not match, it will be forced and the smooth linear reciprocating motion will not occur, galling will occur on the sliding surface and it will not function properly, and the internal gear will be damaged. There is a problem in that the external gear part cannot be assembled in any position other than the standard position.

The present invention has been made in view of the above-mentioned problems, and allows the stroke amount of linear reciprocating motion to be freely and steplessly changed and set to an accurate value by external operation, regardless of whether it is stopped or running. In addition, it functions smoothly even with components having different double eccentricities, and can obtain a long stroke that is not limited to the pitch diameter of the internal gear. On the other hand, it is an object of the present invention to provide a linear reciprocating device in which an external gear part can be assembled at any position.

[Means to solve the problem]

The linear reciprocating device according to the present invention includes an internal gear rotatably installed in a housing having a stroke adjustment means on the outer wall, and a gear having half the number of teeth of the internal gear. a drive block formed of a meshing external gear part, a shaft part rotatably connected to an input shaft directly connected to the rotation axis of the drive source, and a drive arm part having an eccentric drive shaft part; a reciprocating block consisting of a passive frame that vertically slides and holds a rotatably coupled sliding piece; and a sliding rod that abuts and is fixed to both sides of the sliding frame; It consists of a front metal fitting that slides and holds the reciprocating block laterally.

[Effect]

In the linear reciprocating device of the present invention, the eccentric drive shaft portion of the drive block, which rotates in reverse in conjunction with the rotation of the input shaft, slides the rotatably coupled sliding piece in the vertical direction within the passive frame. The reciprocating block is reciprocated in the lateral direction by pushing and pulling it back and forth.

In addition, by operating the stroke adjustment means to change the direction of the trajectory of the sliding piece, the stroke of the reciprocating block can be freely selected, and the direction is parallel to the center line of the sliding rod. The maximum value is obtained when it is, and the minimum value is obtained when it is orthogonal. Note that since one stroke is performed per revolution of the input shaft, the reciprocating speed is highest during the maximum stroke and lowest during the minimum stroke.

The external gear portion can be assembled to the internal gear at any position, and the drive block can be set in a desired posture by operating the stroke adjustment means.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3.

First, I will explain the configuration.

As shown in FIG. 1, the linear reciprocating device 1 of this embodiment is applied to a variable displacement constant pressure piston pump 40, and includes an internal gear 4 rotatably installed in a housing 2, and a variable displacement constant pressure piston pump 40. An external gear part 5g having half the number of teeth and meshing with the internal gear 4, which protrudes from the rear surface of the external gear part 5g and is attached to the input shaft 3 by an eccentric amount H ₁ (within the radius of the pitch circle 5p of the external gear) A drive block 5 consisting of a rotatable shaft part 5j eccentrically supported with a shaft (see FIG. 3) and a drive arm part 5k protruding from the front surface of the external gear part 5g; 5, a reciprocating block 6 that slides in the lateral direction; and a reciprocating block 6 attached to the front surface of the housing 2;
A front metal fitting 7 that slides and holds the reciprocating block 6, and a stroke adjustment means 8 that is provided on the upper outer wall of the housing 2 and that rotates and positions the internal gear 4 to adjust the stroke of the reciprocating block 6. The main components are:

The housing 2 has a worm gear case 2w on the upper outer wall.
It has a worm 8W having a manual handle 8H installed therein, and holds an internal gear 4 having worm wheel teeth 4w carved on the outer periphery to mesh with the worm 8W. Additionally, as shown in FIG. 2, a mounting bracket 3 is attached to the rear surface of the housing 2 as a drive source.
The input shaft 3 is fitted onto the rotary shaft 31 of a motor 30 mounted via the input shaft 2 and is secured by a key 3k, and is held via bearings 3b and 3d.

The drive block 5 has a shaft portion 5j inserted into an eccentric shaft hole 3a formed in the front surface of the input shaft 3, and a bearing 5b.
The centerline of the shaft portion 5j, that is, the centerline _5gc of the external gear portion 5g, is connected to the input shaft 3.
It is eccentric with respect to the center line 3c with an eccentricity amount _H1 .

In addition, the pitch circle 5p diameter d of the external gear part 5g is
This is one half of the pitch circle diameter D of the internal gear 4, and the eccentricity _H1 is equal to one half of the pitch circle diameter d of the pitch circle 5p.

Further, the tip of the drive arm portion 5k forms an eccentric drive shaft portion 5h, and its center line 5h _c is eccentric with an eccentric amount H ₂ (H ₁ +α) with respect to the center line 5g _c . ing. (See FIG. 3) The reciprocating block 6 includes a passive frame 6 provided with a guide groove 6m that longitudinally slides and holds a sliding piece 6K that is coupled to the eccentric drive shaft portion 5h via a bearing 6b.
W, and a pair of sliding rods 6S connected to both outer sides of the passive frame 6W at right angles to the guide groove 6m.

The front metal fitting 7 consists of a holding frame 7W attached to the front surface of the housing 2, and a cover plate 7F attached to cover the front surface, and the passive frame 6W is attached to the upper and lower inner surfaces of the holding frame 7W.
A guide groove 7m is formed as a guide mechanism for sliding the holding frame 7W in the lateral direction, and a bearing hole 7a and a bearing 7j are formed to hold the sliding rod 6S through both side walls of the holding frame 7W.
has been established.

In this embodiment, one of the bearing holes 7a has
The cylinder 41 of the piston pump 40 is connected to the tip of the sliding rod 6S on that side.
A piston 42 is attached.

The center line 6S _c of the sliding rod 6S is always perpendicular to the center line 3c of the input shaft 3 at point C.

Incidentally, in the piston pump 40,
43 is an intake port, 44 is an intake valve, 45 is an exhaust valve, 4
6 is a discharge port.

Next, the assembly of the main parts will be described.

To assemble the reciprocating block 6 to the drive block 5 meshing with the internal gear 4, first, a holding frame 7W is attached to the front surface of the housing 2. And the third
As shown in the figure, at the point C, the sliding rod 6S
The external gear part 5g is placed on the plane F perpendicular to the center line 6S _c of
The drive block 5 is made to take a reference posture such that the center line 5g _c of the eccentric drive shaft portion 5h and the center line 5h _c of the eccentric drive shaft portion 5h are located. However, the internal gear 4 and the external gear part 5g are assembled at any position, and the stroke amount adjusting means 8
may be operated to cause the drive block 5 to take the reference posture.

When the amount of eccentricity is H ₁ =H ₂ , the center line 5h _c coincides with the center line 3 c of the input shaft 3 in this reference posture. . Therefore, the sliding piece 6K held in the guide groove 6m of the passive frame 6W is fitted onto the eccentric drive shaft portion 5h via the bearing 6b, and the passive frame 6W
is set in the guide groove 7m of the holding frame 7W, and both bearing holes 7
After connecting the sliding rod 6S penetrated from a to the passive frame 6W, the cover plate 7F is attached.

With the above assembly, when the input shaft 3 rotates in the direction of the arrow M in this standard posture, the drive block 5 rotates in the direction of the arrow N in conjunction with the rotation of the input shaft 3, and the center line 5h _c of the eccentric drive shaft portion 5h, That is, the sliding pieces 6K having the same center line move in the direction of arrow L along the center line _6sc of the sliding rod 6S, and move the sliding rod 6S in the same direction via the passive frame 6W. When the center line 5g _c of the external gear portion 5g turns 90 degrees from the reference posture position and comes to a position perpendicular to the center line 6s _c , the center line 5h _c of the sliding piece 6K is the pitch circle 4p of the internal gear 4. It has reached the top, and the intersection with the center line 6S _c at that time is point a. When the external gear part 5g further advances 180 degrees, the sliding piece 6K moves in the direction of arrow R and returns to point C, and then advances 270 degrees to reach point b, which is a symmetrical position to point C, and returns from point b. and then face the direction of arrow L again so that the external gear part 5g is aligned with the center line 5g _c
When the sliding piece 6K returns to the plane F, it has returned to the point C. The locus of this series of reciprocating movements of the sliding pieces 6K is a straight line ab, the length of which is equal to the pitch circle diameter D of the internal gear 4, and this is the reciprocating block 6K.
This corresponds to the maximum stroke amount. This maximum stroke amount
S _nax is 2(H ₁ + H ₂ ) = 4H ₁ = D (per H ₁ = H ₂ )
It is. However, the above operation is similar to the conventional example.

Next, to adjust the stroke amount S of the reciprocating block 6, operate the manual handle 8H to adjust the stroke amount S of the worm 8W.
When the internal gear 4 is rotated, for example, in the direction of the arrow Q from the reference posture by the worm wheel teeth 4w by an angle β as shown in the same figure, the external gear portion 5g and the input shaft 3 are integrally rotated following this rotation. The center line 5g _c and the center line 5 of the eccentric drive shaft portion 5h
The plane F ₁ containing h _c and the plane F of the reference posture are at a circumferential angle β
form a degree. At this time, the center line _5hc remains aligned with point C.

When the input shaft 3 is rotated with this plane _F1 as the plane of the initial posture, the center line _5hc of the sliding piece 6K moves in a direction perpendicular to the plane _F1 , so the straight line ef (=D ) passes through point C with respect to the center line 6S _c of the sliding rod 6S and is inclined by an angle β. Therefore, as the input shaft 3 rotates, the sliding piece 6K slides within the guide groove 6m of the passive frame 6W and moves along the straight line ef, but the amount of lateral movement of the passive frame 6W, i.e. The stroke amount S of the reciprocating block 6 is S=D・tanβ, and the value of tanβ is 1.
~ 0, so when β = 90 degrees, S = 0, and the straight line ef overlaps the plane F of the reference posture, and the sliding piece 6
Since K only moves up and down in the vertical direction of point C, the reciprocating block 6 remains stationary. Further, when β=0 degrees, it is the reference attitude of tanβ=1, and as described above, S=D and the maximum stroke amount S _nax is obtained.

In addition, when the amount of eccentricity is H ₂ = H ₁ + α, the trajectory drawn by the sliding piece 6K has a thickness of 2α and a length of the longitudinal center line gh _c of 2, as shown in the figure.
(H ₁ +H ₂ )=2(H ₁ +H ₁ +α)=4H ₁ +2α=D+
2α is the outer circumferential line G of the longitudinal section of the convex lens, and the center line gh _c always has the point C at its center.

When the input shaft 3 is rotated in the standard posture, the maximum stroke amount S _nax =D+ _2α is obtained, and when adjusting the stroke amount, the stroke amount S= (D+2α)
However, since the moving locus of the sliding piece 6K is in the shape of a convex lens, it is parallel to the plane F and at a distance α
When both ends of the center line gh _c are located between the two planes F ₂ and F ₃ , the stroke amount S is an approximate value of 2α, and β=
At 180 degrees, the minimum stroke amount S _nio is obtained as 2α.

Note that the stroke amount can be adjusted regardless of whether the input shaft 3 is stopped or rotating.

Furthermore, although a worm mechanism is used in this embodiment as a stroke adjustment means, the invention is not limited to this. A convex portion is provided on the outer periphery of the internal gear, and a rotatable lever bar is attached to the convex portion. Various other means have been considered, such as a mechanism in which the internal gear is used as a lever to rotate the internal gear by standing up in the radial direction, and a mechanism in which it is folded down and locked into one of the multiple recesses carved into the periphery of the outer casing. It will be done.

Furthermore, in this embodiment, when assembling the main parts,
The external gear portion 5g is meshed with the internal gear 4 so that the drive block 5 assumes a reference posture first.
After the internal gear 4 is assembled into the reference position by operating the stroke adjustment means 8, the internal gear 4 may be rotated to the reference position. However, it can be assembled in any position.

〔Effect of the invention〕

As explained above, the present invention includes an internal gear provided in a housing, a drive block equipped with an external gear portion having half the number of teeth of the internal gear, and a reciprocating block that slides laterally. are connected via a sliding piece provided on a passive frame that is vertically slidable, and
Since the stroke amount adjusting means allows the stroke amount of the reciprocating block to be appropriately selected in one revolution of the input shaft, it is no longer necessary to match the mutual eccentricity of the double eccentrics, and errors and unreasonableness in transmission can be eliminated by the passive frame. Since it is absorbed and relaxed, galling does not occur on the sliding surface. Further, by making the eccentricity of the eccentric drive shaft portion larger than the eccentricity of the external gear portion, the entire device can be downsized.

The drive block can be assembled to the internal gear at any position on the internal gear, which is extremely simple.

Furthermore, since the stroke amount can be selected, it is possible to finely adjust the stroke amount, and not only can accurate stroke amount be obtained at all times, but when applied to a piston pump, it can be adjusted instantly regardless of whether the pump is running or stopped. It has become possible to perform stepless changes in flow rate. In addition, not only the stroke amount but also the stroke speed can be changed steplessly, so when applied to a saw machine, it has many benefits such as the ability to freely select the cutting speed suitable for hard and soft workpieces. It is something that plays.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway front view of a linear reciprocating device according to an embodiment of the present invention, FIG. 2 is a partially cutaway side view of the main part, and FIG. 3 is for explaining the operation of the drive block. This is a schematic front view showing the main parts of the .This figure is a diagram in the case of the standard posture under the condition that the amount of double eccentricity is equal. This figure shows the case of the standard posture under the condition that the eccentricity of the eccentric drive shaft part is large and the eccentricity of the external gear part is large, and the figure shows the case of stroke adjustment. Similarly, the external gear part is advanced by 90 degrees in circumferential angle from the reference position to obtain the minimum stroke amount. Figure 4 shows the piston pump installed in the position where the drive block of the conventional linear reciprocating device has reached the leftmost end. FIG. 5 is a partially cutaway vertical front view when the reciprocating block is in the intermediate position, and FIG. 6 is a cross-sectional plan view in the case of
Similarly, this is a schematic front view showing the main parts for explaining the operation of the drive block.
This figure shows the case where the vehicle moves 45 degrees, and the same figure shows the case where the vehicle moves 90 degrees. 1... Linear reciprocating device, 2... Housing, 3... Input shaft, 4... Internal gear, 5... Drive block, 5g
...External gear part, 5j...Shaft part, 5k...Drive arm part, 5h...Eccentric drive shaft part, 6...Reciprocating block, 6K...Sliding piece, 6W...Passive frame, 6S...
Sliding rod, 7...Front metal fitting, 7W...Holding frame, 7m
...Guide groove, 7a...Bearing hole, 7F...Cover plate, 8
...Stroke adjustment means, 30...Motor, 31...
Axis of rotation.

Claims (1)

[Claims] 1. An internal gear that is rotatably installed inside the housing, an external gear that has a diameter that is half the diameter of the internal gear and meshes with the internal gear, and an eccentric shaft that protrudes from the rear surface of the external gear and is connected to the input shaft. a drive block consisting of a supported shaft and a drive arm with an eccentric drive shaft formed at the tip protruding from the front surface of the external gear; a sliding piece that rotatably holds the eccentric drive shaft; A reciprocating block consisting of a passive frame for linearly sliding a sliding piece in the vertical direction and a plurality of sliding rods connected to both outer sides of the passive frame at right angles to the vertical direction, and a front surface of the casing. A front metal fitting is formed by attaching a cover plate to a holding frame that is attached to a holding frame and has a guide mechanism that allows the passive frame to reciprocate in the lateral direction and a bearing hole that penetrates and holds the sliding rod, and A linear reciprocating device comprising a stroke adjusting means for changing the stroke of a reciprocating block by rotating an internal gear, and the input shaft connected and fixed to a rotating shaft of a drive source.