WO2001059328A1

WO2001059328A1 - Device for interconverting rotary reciprocating movement

Info

Publication number: WO2001059328A1
Application number: PCT/KZ2000/000003
Authority: WO
Inventors: Vladimir Aleksandrovich Vorogushin; Pavel Andreyevich Shishkin
Original assignee: Vorogushin Vladimir Aleksandro; Pavel Andreyevich Shishkin
Priority date: 2000-02-14
Filing date: 2000-06-26
Publication date: 2001-08-16

Abstract

The invention relates to engine manufacturing, in particular, to the devices of conversion of rotary-to-reciprocating movement, comprising a gear which is in alternate engagement with gear racks of a movable frame. To eliminate an impact effect of the gear transfer from the engagement with one gear rack into the engagement with another one, the gear racks of a frame (2) of the proposed device are extented on each end by toothed semicircles of a greater radius than that of a rotating gear (1). The gear frame and the toothed gear have the freedom of crosswise reciprocating movement relative to each other. The proposed dynamic fixing device (fig. 3) is distinguished by the fact that a cam (6) with a cicular arc-shaped working face is fixed along the gear axis, and also, linear rests (7) with their working face making contact with the working face of the cam, are fixed lengthwise the gear racks.

Description

DEVICE FOR INTERCONVERTING ROTARY AND RECIPROCATING MOVEMENT

The invention relates to the field of engine manufacturing, compressor manufacturing, namely, to the device of conversion of rotary movement into reciprocating movement (and vice versa). It has been known of rotary-to-reciprocating movement conversion devices, comprising a crank-and-rod mechanism; comprising Balandin mechanism (see S. S. Balandin "Axial internal-combustion engines", Mechanical Engineering 1972, pages 19,20, Fig.13); comprising a pin-toothed disk, rotating unidirectionally or a toothed gear, being in alternate engagement with gear racks of a movable frame (see FRG Patent No.3529921, cl. F02B 75/32,1987; see "Mechanisms", edited by S.N.Kozhevnikov, Mechanical Engineering 1976, page 488, fig.7.120).

The most similar in technical principle to the proposed technical solution is the rotary-to- reciprocating movement conversion device, comprising a pin-toothed disk, rotating unidirectionally and being in alternate engagement with gear racks of a movable frame (see "Mechanisms" edited by S.N.Kozhevnikov, Mechanical Engineering 1976, page 488, fig.7.120.)

In the said device a pin-toothed disk rotating into one direction alternately comes into action with the upper and the lower gear racks, transmitting the peripheral force via them and changing the direction of the frame reciprocating movement. For disengagement of pin teeth of the disk with one gear rack at the moment of coming into engagement with another one, pin teeth (or teeth) are arranged only on the half perimeter of the reference circle of a disk (or a toothed gear), and part of the teeth of the gear racks is outlying. In this case in the process of the disk rotation a pin tooth and the first tooth of a rack are approaching one another with collision without maintaining the constancy of engagement parameters, thus permitting to employ the described device only in slow-running, non-critical mechanisms and completely excluding their use in internal-combustion engines; compressors; in the mechanisms, where great mechanical forces are involved and high velocities of reciprocal and rotational movement are observed. The indicated drawbacks do not allow to implement d .sign and technological advantages of the devices of this type caused by the absence of conn .cting rods and a crank shaft. Aim 1 of the invention is to eliminate impact effect when a rotating toothed disk (or pin- toothed disk) changes from engagement with one gear rack to engagement with another one by providing constant mesh c f a toothed gear (or a pin-toothed disk) with a gear frame all along its perimeter. Aim 2 of the invention is to maintain main engagement parameters for any time moment of the cycle by keeping invariable the normal distance L between the gear rotation axis and the pitch line of a gear rack (Fig.1-3).

Aim 1 of the invention is accomplished by the fact that on each end the gear racks of frame 2 are prolonged by toothed semicircles of a major radius than that of rotating gear 1, and gear frame 2 and toothed gear 1 have the freedom of crosswise reciprocating movement relative to each other with the location of their end positions by a fixing device for the time while the gear is rolling over the gear rack . Aim 2 of the invention is accomplished by the fact that location of the end positions of the frame, being the condition of the operational capability of the device as per Aim 1, is carried out by a cam mechanism. In this case cam 6 having a circular arc-shaped working face is fixed in line with toothed gear 1, and linear rests 7 are fixed lengthwise the gear racks, with their working face making contact with that of cam 6. As compared with the prototype the claimed engineering solution is characterized by new essential features as follows:

As to aim 1 :

The gear racks of frame 2 are extended on each end by toothed semicircles with the major radius of a reference circle than that of rotating gear 1 by the value equaling or exceeding '/₂ tooth height. 1.2 Gear frame 2 and the rotation axis C of toothed gear 1 have the freedom of crosswise reciprocating movement relative to each other.

1.2 Gear frame 2 in alternative a) and the rotation axis C of toothed gear 1 in alternative b) are located in their end positions by a fixing device for the time while toothed gear 1 is rolling over one of the gear racks. As to Aim 2:

2.1 Cam 6 having a circular arc-shaped working face is fixed in line with toothed gear 1 and linear rests 7 with their working face making contact with the working face of cam 6 are fixed along the length of the gear racks.

2.2 The length of the working face along the perimeter of the arc of cam 6 equals to the length of the working face of linear rest 7. 2.3 The total number of teeth of gear frame 2 is two times more than the total number of teeth in toothed gear 1.

Fig.l (Fig.4) shows the device of movement conversion by alternative a) with a section view over the plane of action of gear frame 2 and toothed gear 1. Fig.2 shows the device of movement conversion by alternative b) with a section view over the plane of action of gear frame 2 and toothed gear 1.

Fig.3 shows a longitudinal section of the device of dynamic fixing over the plane of action of its cam mechanism.

The device of rotary-to-reciprocating movement conversion

(Fig.l, Fig.2, Fig.4) incorporates:

Toothed gear 1, which is in constant mesh with gear frame 2. Gear frame 2 is designed in the shape consisting of 2 gear racks of similar length and two toothed semicircles of similar radius. The radius of the reference circle of toothed semicircles is constantly major than the radius of the reference circle of gear 1 by the value which equals or exceeds !/_ tooth height. By alternative a) (Fig.l, Fig.4) gear frame 2 is positioned in motion unit 3 and has the freedom of crosswise reciprocating movement, for example, along neck guides 4 (Fig.l). For example, relative to axis Z (Fig.4). Motion unit 3 is confined in stationary housing 5 and has the freedom of lengthwise reciprocating movement in it. By alternative b) (Fig.2) gear frame 2 is fixed in motion unit 3. Also, motion unit 3 is placed in stationary housing 5 and has the freedom of lengthwise reciprocating movement in it. Gear 1 and an output shaft are joined by an assembly, allowing parallel displacement of rotation axes when in operation (for example, by a torsion shaft, a coupling. Cardan joint). As opposed to alternative a) as per Fig. l , by alternative b) as per Fig.2 the diametric size of motion unit 3 can be fully used for the increase in the transverse size of gear frame 2 and the diameter of gear 1, that, with the equality of diameters of cylinders d, ensures achieving of great values of travel S of motion unit 3 and S/d relations. For the location of extreme up and extreme low positions of gear frame 2 by alternative a) and for the location of extreme up and extreme low positions of the rotation axis C of gear 1 by alternative b) (location of L dimension as per Fig.l and Fig.2), the device is equipped with a fixing mechanism, for example: electromagnetic, hydraulic, mechanical (not shown in Fig. land Fig.2) or a dynamic fixing device ( Fig.3). Device of dynamic fixing of gear frame end positions

4

A cam in the shape of a circle sector 6, the working face of which is an arc of the sector of a circle. Cam 6 and gear 1 are seated along one and the same axis- the rotation axis of gear 1 - and they are stationary relative to each other. Along the gear racks are fixed linear rests 7, the working faces of which are the surfaces facing the gear frame axis of symmetry. The working face length along the perimeter of the arc of cam 6 equals to the working face length of linear rest 7. The total number of teeth of frame 2 toothing is two times more than the total number of teeth in gear 1. Gear 1 with cam 6 is brought into action with gear frame 2 so that the horizontal axis of symmetry of gear frame 2 is aligned with X-X axis of symmetry of cam 6. This position of gear 1 corresponds to the upper dead center and the lower dead center in the position of motion unit 3.

The device of conversion of rotary-to-reciprocating movement ( Fig.1, Fig.2) functions as follows:

In the process of rotation of gear 1 (arrowed line) being in action with the lower gear rack of frame 2 according to the sketch of Fig.1 and Fig.2, motion unit 3 with gear frame 2 inserted in it moves to the left. At the moment, when gear 1 is transferring from the section of the lower gear rack to the section of frame 2 toothed semicircle, motion velocity of motion unit 3 is slowing down abruptly, falling off to zero in the point, where the horizontal axis of symmetry of gear frame 2 is in alignment with the diametric line of gear 1. This momentum corresponds to the upper dead center (UDC) of the left face end of motion unit 3 and to the lower dead center (LDC) of the right face end.

By alternative a) (Fig.l) within motion unit 3 concurrently with the transfer of gear 1 from the gear rack section to the toothed semicircle section of frame 2, cross displacement of gear frame 2 is initiated downwards relative to the rotation axis C of gear 1 along Y_P-Y_P axis. The displacement occurs under the effect of cross-axis component force, exerted in the engagement of gear 1 with the toothed semicircle of frame 2.

By alternative b) (Fig.2) within motion unit 3 concurrently with the transfer of gear 1 from the gear rack section to the toothed semicircle section of frame 2, on the contrary, cross displacement of the rotation axis C of gear 1 is initiated upwards relative to gear frame 2 in housing 5 along Y_k - Y|_< axis under the effect of the similar cross-axis component force, exerted in the engagement. In the above indicated UCD-LCD point the cross movement of gear frame 2 as per Fig.1 or of the rotation axis C of gear 1 as per Fig.2 is equal to ^lΛ of their complete travel in the transverse direction, i.e. +D. The crosswise movement by 2D size is fully ceased at the moment of gear 1 transfer from the toothed semicircle section to the upper gear rack section

140 of frame 2. At that very instant the teeth of gear 1 are wholly coming out of action with the lower gear rack and are engaging with the upper rack. Motion of unit 3 with gear frame 2 is initiated in the opposite direction, i.e. to the right from the above indicated UDC-LDC point with the drastic linear velocity increase from zero. The process of further gear rolling over the gear rack with the transfer to the left toothed semicircle and then from it to the lower

145 gear rack and all the processes coming about in this case, are similar to those described.

Device of dynamic fixing of gear frame end positions relative to toothed gear at crosswise movement (Fig.3) functions as follows:

150 In the process of rotation of gear 1. being in constant mesh with gear frame 2, its alternate transfer takes place from one gear rack to another one by way of toothed semicircles. Operation of a dynamic fixing device (Fig.3) in the movement conversion device by alternative a) as per Fig. l and by alternative b) as per Fig.2 do not differ fundamentally. Here, due to the fact that the cam and the linear rest working faces are similar in length, at

155 any moment of gear 1 rolling over the gear rack along one side, commonly, on the diametrically opposite side there is a supporting contact between the working faces of cam 6 and linear rest 7, thus ensuring mutual holding of gear frame 2 and gear 1 from crosswise movement. By alternative a), at the moment when the engagement is changing from the gear rack to the

160 toothed semicircle (A₂-B₂ momentum) B| edge of cam 6 comes closer to Aι edge of the linear rest and passing over it, ceases the location of gear frame 2 which starts displacing downwards by +D size under the effect of cross-axis component force, exerted in the engagement of gear 1 and the toothed semicircle of frame 2. Similarly, by alternative b) it is ceased the location of the rotation axis C of gear 1 which

165 starts displacing upwards by +D value along Y_k-Y_k axis under the effect of the similar force. The process of mutual displacement of frame 2 and gear 1 by alternatives a) and b) occurs with the drawing together of the horizontal axis of symmetry of gear frame 2 with the axis of symmetry X-X of cam 6. The moment of their alignment corresponds to UDC-LDC point. In this point motion unit 3 has zero transitional Λ elocity. By alternative a) gear frame 170 2 (or gear 1 by alternative b) ) has covered '/₂ of the displacement travel (D), and cam 6 is positioned symmetrically rela;ive to the toothed semicircle arc and to the linear rests 7. Here Bj and B ₂ edges of cam 6 b; ' their face ends are making contact with the face ends of A\ and A ₂ edges of linear rests 7, ensuring further momentary fixing of motion unit 3 holding it from lengthwise displacement for the time of gear 1 change-over from one gear

175 rack to another one.

The passing through UDC-LDC point occurs with the further crosswise movement of gear frame 2 and gear 1 relative to each other by the remaining half of the displacement travel (-D). Motion unit 3 initiates lengthwise movement in the opposite direction. Gear 1 rolling further over the toothed semicircle arc, reaches the point of the change-over to the

180 upper gear rack, where Bi edge of the cam occupies the same position as B₂ edge in Fig.3. In its turn, B₂ edge passes over A₂ edge of the linear rest and comes out to its working face (i.e. the position of B₂ edge becomes similar to that of Bj edge in Fig.3). From that moment gear frame 2 by alternative a) (or gear 1 by alternative b) ) is get fixed again. Gear 1 is rolling over the upper gear rack. Carrying out an opposite rotation, the cam is sliding over

185 the working face of linear rest 7. Motion unit 3 is moving to the right. By the end of the period of gear 1 rolling over the upper gear rack the contact line between cam 6 and linear rest 7 has traveled the whole working face length of the cam and the linear rest simultaneously. Here, the cam is found to be turned by 180°(reflection, Fig.3) and the whole process described of relative displacement of gear frame 2 and of the rotation axis C of gear

190 1 in the opposite direction by alternatives a) and b) with fixing of their end positions is reiterated.

Continuous engagement of gear 1 with gear frame 2 over the whole perimeter ensures smooth, shock free operation of the device both by alternative a) and by alternative b) and the engagement parameters are maintained constant by keeping invariable the normal

195 distance L between the rotation axis C of gear 1 and the pitch line of the gear rack, resulting in kinematic interaction of cam 6 with linear rests 7 of the dynamic fixing device.

Claims

CLAIM. 1. Device of rotary-to-reciprocating movement conversion, comprising a unidirectionally rotating toothed gear (or pin-toothed disk) being in alternate engagement with gear racks of a movable frame, is distinctive in that the gear racks of frame 2 on each end are extended by toothed semicircles of a major radius than that of rotating toothed gear 1, and gear frame 2 and the rotation axis C of gear 1 have the freedom of crosswise reciprocating movement relative to each other with location of the end positions by a fixing device.

2. Movement conversion device as per item 1, is distinctive in that the radius of a dividing circumference of toothed semicircles is major than the radius of a reference circle of toothed gear 1 by the value equaling or exceeding ^lA tooth height.

3. Movement conversion device as per item 1, is distinctive in that the rotation axis C of gear 1 is stationary in housing 5, and gear frame 2 has the freedom of crosswise reciprocating movement in the direction of Y_p -Y_p axis relative to the rotation axis C of gear 1.

4. Movement conversion device as per item 1, is distinctive in that gear frame 2 is fixed in motion unit 3, and the rotation axis C of gear 1 has the freedom of crosswise reciprocating movement relative to motion unit 3 and housing 5 in the direction of Y -Y_k axis.

5. Device of dynamic fixing of gear frame end positions relative to the gear at crosswise movement, having an invariable distance L from the pitch line of a gear rack to the gear rotation axis, is distinctive in that a cam with a circular arc-shaped working face is fixed in line with the gear rotation axis, and linear rests 7 are secured along the length of the gear racks, making contact with the working face of cam 6.

6. The fixing device as per item 5, is distinctive in that the working face length along the perimeter of the arc of cam 6 is equal to the working face length of linear rests 7.

7. The fixing device as per item 5, is distinctive in that the total number of teeth of gear frame 2 is two times more than the total number of teeth in toothed gear 1.