CN1093027C - Transmission mechanism - Google Patents

Abstract

The present invention discloses a transmission device which has the structure that an edge cam can be installed on a frame through a spline pair in a slide mode, a spring is arranged between the frame and the edge cam, a retainer can be installed on a cam shaft in a rotation mode, a roller fixed on the retainer is butted with a cam surface unit, and the rotation of the retainer drives the roller to roll along the cam surface unit. The present invention generates a motion law (energy storage-quick discharge) through the combination of the edge cam, the spring and the roller by using the characteristic (the cam surface unit) of the edge cam so as to convert the rotation into a linear shock motion.

Description

A kind of transmission device

Technical field

The present invention relates to a kind of transmission device.

Background technology

The percussion drill of people's use at present generally has two kinds of forms: a kind of is air-cylinder type, and it utilizes the cooperation of cylinder, pneumatic hammer to produce straight line shock; Another kind is to produce pulsation with impact block to realize straight line shock.First kind of form structure complexity, the cost height; Second kind of form is because the axial displacement that impact block produces is little, and result of use is not good, and very easily wearing and tearing.

Summary of the invention

Main technical schemes of the present invention is: edge cam is slidably mounted on the frame by spline pair, between frame and edge cam, spring is housed, retainer is contained on the camshaft rotationally, the roller that is fixed on the retainer is resisted against on the cam surface unit 12, the rotation of retainer 4 drives roller 5 12 rollings along the cam surface unit, and the equation of locus of roller center of mass motion is in upward stroke: $\frac{d^2\mathrm{<figure-callout\; id="2"\; label="y\; dx"\; filenames="C0011725200061.png"\; state="\{\{state\}\}">y</figure-callout>}}{{\mathrm{dx}}^{}}=A_1\mathrm{Cos\&alpha;rctg}\frac{\mathrm{dy}}{\mathrm{dx}}-0.08A_1\mathrm{Sin\&alpha;rctg}\frac{\mathrm{dy}}{\mathrm{dx}}-A_{2}y-A_3$

According to imperial lattice one Coorg integration method, determine that the span of A1, A2, A3, α is: 250≤A1≤500,4 * 10 ⁴≤ A2≤7.5 * 10 ⁴, 250≤A ₃≤ 375,15 °≤α≤25 °, wherein α is roller and cam surface initial contact position tangential direction and horizontal direction angle, and cam surface unit 12 is to be center of rotation with the roller barycenter, makes the formed enveloping surface of pure rolling by centroid trajectory, in backhaul, cam surface 12 is clinoplains.

The normal pressure that the equation of locus of the present invention by the roller center of mass motion can obtain arbitrary contact point on the cam surface of edge cam equates.Thereby the raising transmission efficiency alleviates mechanical wear.Simultaneously, it is unsettled suddenly that the present invention utilizes roller to arrive behind the peak, and energy-stored spring is anxious to be put, and orders about camshaft to variable accelerated motion, when end speed and drill bit retainer generation non-perfect elastic collision and produce and impact output, good working effect, reliable operation.

Description of drawings

Fig. 1 is a kinematic sketch of the present invention;

Fig. 2 is the roller center of mass motion track of a cam unit correspondence in the one embodiment of the invention;

Fig. 3 is the roller center of mass motion track exploded view of one embodiment of the invention;

Fig. 4 is that roller cooperates partial schematic diagram with edge cam;

Fig. 5 is the side-looking partial schematic diagram of Fig. 4.

The specific embodiment

As Fig. 1, Fig. 2, shown in Figure 3, edge cam 1 of the present invention slidably is installed on the frame 2 by spline pair, between frame 2 and edge cam 1, spring 3 is housed, retainer 4 is contained on the camshaft rotationally, the roller 5 that is fixed on the retainer 4 is resisted against on the cam surface unit 12, the rotation of retainer 4 drives roller 5 12 rollings along the cam surface unit, and the equation of locus of roller center of mass motion is in upward stroke: $\frac{d^2\mathrm{<figure-callout\; id="2"\; label="y\; dx"\; filenames="C0011725200061.png"\; state="\{\{state\}\}">y</figure-callout>}}{{\mathrm{dx}}^{}}=A_1\mathrm{Cos\&alpha;rctg}\frac{\mathrm{dy}}{\mathrm{dx}}-0.08A_1\mathrm{Sin\&alpha;rctg}\frac{\mathrm{dy}}{\mathrm{dx}}-A_{2}y-A_3$

According to imperial lattice one Coorg integration method, determine that the span of A1, A2, A3, α is: 250≤A1≤500,4 * 10 ⁴≤ A2≤7.5 * 10 ⁴, 250≤A ₃≤ 375,15 °≤α≤25 °, wherein α is roller and cam surface initial contact position tangential direction and horizontal direction angle, cam surface unit 12 is to be center of rotation with the roller barycenter, make the formed enveloping surface of pure rolling along centroid trajectory, in backhaul, cam surface unit 12 is clinoplains.One group of above cam surface unit 12 is arranged on the edge cam 1, in an embodiment, four groups of above-mentioned cam surface unit 12 are arranged on the edge cam.

As Fig. 4, shown in Figure 5, cam surface unit 12 outer rims are conical surfaces, roller 5 partly is the identical frustum of tapering 51 with cam surface unit 12 outer rim cone match, and because of the linear velocity difference of the point of different radii on the edge cam, aforementioned structure can guarantee that roller makes pure rolling along setting track.Another part is the semicolumn 52 that can cooperate with cam surface unit 12 on the roller 5, and the normal travel on the conical surface stroke ratio cam surface unit is short, and progressive error equals the maximum radius of frustum 51.Unsettled suddenly when roller arrives peak, make the appoint power pop-off of roller, system unloaded to cam surface.Make the maximum momentum of edge cam generation in the backhaul.

Transmission device of the present invention can be widely used in the electric tool as nailing machine, hand punch, and in other mechanism driving.

Claims (3)

1, a kind of transmission device, it is characterized in that: edge cam (1) slidably is installed on the frame (2) by spline pair, between frame (2) and edge cam (1), spring (3) is housed, retainer (4) is contained on the camshaft rotationally, the roller (5) that is fixed on the retainer (4) is resisted against on the cam surface unit (12), the rotation of retainer (4) drives roller (5) and rolls along cam surface unit (12), and the equation of locus of roller center of mass motion is in upward stroke: $\frac{d^{2}y}{{\mathrm{dx}}^2}=A_1\mathrm{Cos\&alpha;rctg}\frac{\mathrm{dy}}{\mathrm{dx}}-0.08A_1\mathrm{Sin\&alpha;rctg}\frac{\mathrm{dy}}{\mathrm{dx}}-A_{2}y-A_3$

According to imperial lattice one Coorg integration method, determine that the span of A1, A2, A3, α is: 250≤A1≤500,4 * 10 ⁴≤ A2≤7.5 * 10 ⁴, 250≤A ₃≤ 375,15 °≤α≤25 °, wherein α is roller and cam surface initial contact position tangential direction and horizontal direction angle, cam surface unit (12) is to be center of rotation with the roller barycenter, make the formed enveloping surface of pure rolling along centroid trajectory, in backhaul, cam surface unit (12) are clinoplains.

2, a kind of transmission device according to claim 1, it is characterized in that: cam surface unit (12) outer rim is the conical surface, roller (5) partly is the identical frustum of tapering (51) with cam surface unit (12) outer rim cone match, it is the semicolumn (52) that can cooperate with cam surface (12) that roller (5) is gone up another part, normal travel on the conical surface stroke ratio cam surface unit is short, and its progressive error equals the maximum radius of frustum (51).

3, a kind of transmission device according to claim 1 and 2 is characterized in that: one group of above cam surface unit (12) is arranged on the edge cam (1).

Images