CN105843283A - Camshaft grinding processing thermostatic control device and method - Google Patents

Abstract

The invention provides a constant temperature control device and method for camshaft grinding. The device includes a power measurement module for measuring the power of the motor in real time and outputting the power; a constant temperature control module for receiving the power output from the power measurement module Power, and calculate the maximum temperature on the surface of the current grinding wheel and camshaft contact area according to the power and the preset constant temperature control model; the constant temperature control module is also used to compare the maximum temperature with the preset temperature threshold, if it is judged that the maximum temperature is higher than or equal to the preset temperature threshold, the motor is controlled to reduce the camshaft rotation speed, and the cutting depth of the camshaft by the grinding wheel is reduced. The device provided by the invention can adjust the processing temperature in real time so that the temperature of the surface of the camshaft is at the highest allowable temperature value, avoiding the grinding burn of the camshaft, improving the processing efficiency, thereby improving the quality of the camshaft and prolonging the service life of the camshaft.

Description

Constant temperature control device and method for camshaft grinding

technical field

The invention belongs to the technical field of part processing, in particular to a constant temperature control device and method for camshaft grinding.

Background technique

The camshaft is an important part in the valve train of an automobile engine, which controls the opening and closing of the valves of the automobile engine. Since the cam profile is a special-shaped surface, the processing technology and scheme are relatively complicated, especially the processing quality of the cam surface, which directly determines whether the camshaft will produce impact and friction between the valve and the cam during the intake and exhaust working cycles of the engine. Vibration, which affects the stability of the car engine in operation. The quality of the camshaft depends directly on the quality of the cam grinding process.

The profile of the cam is very complicated, the machining accuracy is high, the machining is difficult, and the machining process control is difficult. At present, cam grinding relies heavily on the operator's experience and intuition. Although computer programs that provide parameterized machining speeds do exist when the dynamic constraints of the machine tool and the cam profile are known, however, even with the support of computer programs, a large number of repeated grinding experiments are still required to adjust, and these adjustments also rely on experience. technical workers. In addition, some manufacturers choose to reduce the single feed of the grinding wheel when the grinding burn phenomenon occurs in the cam, and others choose to reduce the processing speed. While this "feel-only" change will eliminate grinder burn to some extent, it can seriously affect machining efficiency. The above-mentioned processing method based on workers' experience has defects such as untimely feedback, low processing efficiency, and high material waste rate, which is not conducive to improving the processing quality stability and processing efficiency of batch camshaft production.

Contents of the invention

The invention aims to solve the problems that the existing camshaft processing method only relies on the experience and intuition of the operator to process the camshaft, which makes the camshaft prone to grinding burns, low processing efficiency and the like.

In order to achieve the above purpose, the present invention provides a constant temperature control method and device for camshaft grinding.

In a first aspect, the present invention provides a constant temperature control device for camshaft grinding, including:

The power measurement module is used to measure the power of the motor in real time and output the power, wherein the motor is a motor of a grinding wheel electric spindle for grinding a camshaft;

A constant temperature control module, configured to receive the power output by the power measurement module, and calculate the current maximum temperature of the surface of the contact area between the grinding wheel and the camshaft according to the power and a preset constant temperature control model;

The constant temperature control module is also used to compare the maximum temperature with a preset temperature threshold, and if it is determined that the maximum temperature is higher than or equal to the preset temperature threshold, control the motor to reduce the camshaft speed Or reduce the depth of cut of the grinding wheel on the camshaft.

Preferably,

The constant temperature control module is further configured to control the motor to increase the rotation speed of the camshaft and increase the cutting depth of the camshaft by the grinding wheel if it is determined that the maximum temperature is lower than the preset temperature threshold.

Preferably,

If the constant temperature control module judges that the power is greater than the power threshold that needs to be trimmed, it controls the motor to stop working, and sends an alarm instruction for trimming or replacing the grinding wheel.

Preferably,

The preset constant temperature control model is realized by the following formula, specifically:

${\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; P</span>}}{\mathrm{<span\; class="notranslate">\; b</span>}\mathrm{<span\; class="notranslate">\; c</span>}\mathrm{<span\; class="notranslate">\; \&rho;</span>}}\sqrt{{\mathrm{<span\; class="notranslate">\; L</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; /</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}$

Wherein, θ _m is the highest temperature on the surface of the contact area between the current grinding wheel and the camshaft; γ is the temperature correction coefficient of the constant temperature control model; P is the current power of the motor; b is the width of the camshaft; ρ is the material density of the camshaft; c is the specific heat capacity of the camshaft; i is the angle of the camshaft; L _i is the contact arc length corresponding to every i degree camshaft; v _i is the instantaneous linear velocity of every i degree camshaft.

Preferably,

The contact arc length Li corresponding to each _i degree camshaft is realized by the following formula, specifically:

${\mathrm{<span\; class="notranslate">\; L</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>\sqrt{\frac{{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; \&CenterDot;</span>{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; \&CenterDot;</span>{\mathrm{<span\; class="notranslate">\; a</span>}}_{\mathrm{<span\; class="notranslate">\; e</span>}}}{{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}}$

Among them, i is the angle of the camshaft; d _s is the diameter of the grinding wheel; d _i is the equivalent diameter of the camshaft corresponding to every i degree; a _e is the cutting depth of the grinding wheel on the camshaft;

The instantaneous linear velocity v of the camshaft per _i degree is realized by the following formula, specifically:

${\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}{\mathrm{<span\; class="notranslate">\; 60</span>}}<span\; class="notranslate">\; \&CenterDot;</span>\mathrm{<span\; class="notranslate">\; \&pi;</span>}<span\; class="notranslate">\; \&CenterDot;</span>{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}$

Among them, i is the angle of the camshaft; d _i is the equivalent diameter of the camshaft corresponding to every i degree; n _i is the instantaneous speed of the camshaft every i degree.

In a second aspect, the present invention provides a constant temperature control method for camshaft grinding, including:

The power measurement module measures the power of the motor in real time, and outputs the power, wherein the motor is the motor of the grinding wheel electric spindle that grinds the camshaft;

The constant temperature control module receives the power output by the power measurement module, and calculates the maximum temperature on the surface of the current grinding wheel and the camshaft contact area according to the power and the preset constant temperature control model;

The constant temperature control module compares the maximum temperature with a preset temperature threshold, and if it is determined that the maximum temperature is higher than or equal to the preset temperature threshold, it controls the motor to reduce the camshaft speed or reduce the grinding wheel speed. Depth of cut to the camshaft.

Preferably, the method also includes:

If the constant temperature control module determines that the highest temperature is lower than the preset temperature threshold, it will control the motor to reduce the camshaft speed and increase the cutting depth of the camshaft by the grinding wheel.

Preferably, the method also includes:

If the constant temperature control module judges that the power is greater than the power threshold that needs to be trimmed, it controls the motor to stop working, and sends an alarm instruction for trimming or replacing the grinding wheel.

Preferably, the preset constant temperature control model is realized by the following formula, specifically:

${\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; P</span>}}{\mathrm{<span\; class="notranslate">\; b</span>}\mathrm{<span\; class="notranslate">\; c</span>}\mathrm{<span\; class="notranslate">\; \&rho;</span>}}\sqrt{{\mathrm{<span\; class="notranslate">\; L</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; /</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}$

Wherein, θ _m is the highest temperature on the surface of the contact area between the current grinding wheel and the camshaft; γ is the temperature correction coefficient of the constant temperature control model; P is the current power of the motor; b is the width of the camshaft; ρ is the material density of the camshaft; c is the specific heat capacity of the camshaft; i is the angle of the camshaft; L _i is the contact arc length corresponding to every i degree camshaft; v _i is the instantaneous linear velocity of every i degree camshaft.

Preferably, the contact arc length L _i corresponding to the camshaft per i degree is realized by the following formula, specifically:

${\mathrm{<span\; class="notranslate">\; L</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>\sqrt{\frac{{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; \&CenterDot;</span>{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; a</span>}}_{\mathrm{<span\; class="notranslate">\; e</span>}}}{{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}}$

Among them, i is the angle of the camshaft; d _s is the diameter of the grinding wheel; d _i is the equivalent diameter of the camshaft corresponding to every i degree; a _e is the cutting depth of the grinding wheel on the camshaft;

The instantaneous linear velocity v of the camshaft per _i degree is realized by the following formula, specifically:

${\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}{\mathrm{<span\; class="notranslate">\; 60</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; \&pi;</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}$

Among them, i is the angle of the camshaft; d _i is the equivalent diameter of the camshaft corresponding to every i degree; n _i is the instantaneous speed of the camshaft every i degree.

In the constant temperature control device for camshaft grinding provided by the present invention, the power measurement module measures the power of the motor in real time and outputs the result to the constant temperature control module, and the constant temperature control module calculates the maximum temperature of the current camshaft contact surface according to the power and compares it with The temperature threshold is compared, and the processing temperature is adjusted in real time according to the comparison result so that the temperature of the camshaft surface is at the highest allowable temperature value, which can not only avoid the camshaft grinding burn, but also improve the processing efficiency, thereby improving the quality of the camshaft , Extend the service life of the camshaft.

Description of drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the accompanying drawings that need to be used in the description of the embodiments. Obviously, the accompanying drawings in the following description are only of the present invention. For some examples, those of ordinary skill in the art can also obtain other drawings based on these drawings on the premise of not paying creative efforts.

Fig. 1 is the embodiment structural representation of the constant temperature control device of camshaft grinding process provided by the present invention;

Fig. 2 is a schematic diagram of a triangular distribution heat source model provided by the present invention;

Fig. 3 is a schematic diagram of the geometric relationship of the camshaft plunge mill provided by the present invention;

Fig. 4 is a comparison diagram of Vickers hardness of cam lift after grinding provided by the present invention;

Fig. 5 is a comparison diagram of surface roughness of cam lift after grinding provided by the present invention;

Fig. 6 is a flow chart of an embodiment of the constant temperature control method for camshaft grinding provided by the present invention.

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

In a first aspect, the present invention provides an embodiment of a constant temperature control device for camshaft grinding, as shown in Figure 1, comprising:

The power measurement module 101 is used to measure the power of the motor in real time and output the power, wherein the motor is a motor that drives the camshaft to rotate and drives the grinding wheel to grind the camshaft;

The constant temperature control module 102 is used to receive the power output by the power measurement module, and calculate the maximum temperature on the surface of the contact area between the current grinding wheel and the camshaft according to the power and the preset constant temperature control model;

The constant temperature control module 102 is also used to compare the maximum temperature with the preset temperature threshold. If it is judged that the maximum temperature is higher than or equal to the preset temperature threshold, the motor is controlled to reduce the camshaft speed or reduce the cutting depth of the camshaft by the grinding wheel .

In the constant temperature control device for camshaft grinding provided by the embodiment of the present invention, the power measurement module measures the power of the motor in real time and outputs it to the constant temperature control module. The temperature threshold is compared, and the processing temperature is adjusted in real time according to the comparison result so that the temperature of the camshaft surface is at the highest allowable temperature value, which can not only avoid the camshaft grinding burn, but also improve the processing efficiency, thereby improving the quality of the camshaft , Extend the service life of the camshaft.

In a specific implementation, the constant temperature control module 102 is also used to control the motor to increase the camshaft speed or increase the cutting depth of the camshaft by the grinding wheel if it is determined that the maximum temperature is lower than the preset temperature threshold. That is to say, when the temperature of the surface of the camshaft has not reached the maximum allowable temperature value (that is, the temperature threshold), the machining efficiency can be improved by increasing the rotational speed of the camshaft or the depth of cut.

In specific implementation, in order to repair or replace the grinding wheel in time after the grinding wheel wears out, the constant temperature control module is also used to control the motor to stop working and send Alarm indication for dressing or changing the grinding wheel. After receiving such a prompt, the operator trims or replaces the grinding wheel before continuing to process, thereby avoiding the waste caused by excessive trimming and the degradation of processing quality caused by untimely trimming or replacement.

In specific implementation, the preset constant temperature control model here can be implemented in various ways, and one of the implementation ways will be described in detail below:

The preset constant temperature control model can be realized by formula (1), specifically:

${\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}<span\; class="notranslate">\; \&CenterDot;</span>\mathrm{<span\; class="notranslate">\; P</span>}}{\mathrm{<span\; class="notranslate">\; b</span>}\mathrm{<span\; class="notranslate">\; c</span>}\mathrm{<span\; class="notranslate">\; \&rho;</span>}}\sqrt{{\mathrm{<span\; class="notranslate">\; L</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; /</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

In formula (1), _θm is the maximum temperature of the surface of the contact area between the current grinding wheel and the camshaft; γ is the temperature correction coefficient of the constant temperature control model; P is the current power of the motor; b is the width of the camshaft; ρ is the camshaft c is the specific heat capacity of the camshaft; i is the angle of the camshaft; L _i is the contact arc length corresponding to every i degree camshaft; v _i is the instantaneous linear velocity of every i degree camshaft.

Among them, the temperature correction coefficient γ of the constant temperature control model here is obtained according to the experimental data; the width b of the camshaft, the material density ρ of the camshaft, and the specific heat capacity c of the camshaft are all properties of the camshaft itself, which can be determined by The operator manually enters into the thermostatic control module.

The specific derivation process of its preset constant temperature control model will be described in detail below.

The temperature distribution on the cam surface conforms to the triangular distribution heat source model shown in Figure 2. As shown in Figure 2, along the grinding zone, the thickness of the grinding debris is uneven, with a maximum value around the front of the grinding zone, and close to 0 at the tail, so a triangular heat flow distribution in the grinding zone is more reasonable . For the assumption of a triangular heat distribution on BC, at instant d _τi (τ _e ≤τ _i ≤τ ₀ ) at time τ, the instantaneous heat flux emitted from BC across point D(x,0) is The time interval from this time to τ ₀ is equal to: τ=τ ₀ −τ _i .

The temperature rise at point D near the BC surface of a semi-infinite solid can be calculated by a method similar to the equation, as shown in equation (2):

$\mathrm{<span\; class="notranslate">\; d</span>}\mathrm{<span\; class="notranslate">\; \&theta;</span>}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}<span\; class="notranslate">\; \&CenterDot;</span>\mathrm{<span\; class="notranslate">\; P</span>}}{\mathrm{<span\; class="notranslate">\; b</span>}\mathrm{<span\; class="notranslate">\; c</span>}\mathrm{<span\; class="notranslate">\; \&rho;</span>}}{<span\; class="notranslate">\; \&Integral;</span>}_{{\mathrm{<span\; class="notranslate">\; \&tau;</span>}}_{\mathrm{<span\; class="notranslate">\; e</span>}}}^{{\mathrm{<span\; class="notranslate">\; \&tau;</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}}\frac{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\frac{{\mathrm{<span\; class="notranslate">\; \&tau;</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; \&tau;</span>}}_{\mathrm{<span\; class="notranslate">\; e</span>}}}{{\mathrm{<span\; class="notranslate">\; \&tau;</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}}}{{\mathrm{<span\; class="notranslate">\; \&tau;</span>}}^{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; 2</span>}}}{\mathrm{<span\; class="notranslate">\; e</span>}}^{<span\; class="notranslate">\; -</span>\frac{{\mathrm{<span\; class="notranslate">\; z</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}{\mathrm{<span\; class="notranslate">\; 4</span>}{\mathrm{<span\; class="notranslate">\; \&tau;</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}}{\mathrm{<span\; class="notranslate">\; L</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}{\mathrm{<span\; class="notranslate">\; d\&tau;</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>$

The above equation is solved by several integrals:

The temperature rise on the surface of the contact zone is Z=0.

Let τ _e =0, and When τ ₀ =2τ _i , that is , the highest temperature on the surface of the contact area between the current grinding wheel and the camshaft is obtained as shown in formula (1).

In specific implementation, the contact arc length L _i corresponding to every i degree camshaft in formula (1) can be obtained according to the schematic diagram of the geometric relationship of the camshaft cut-in mill shown in Figure 3, specifically:

${\mathrm{<span\; class="notranslate">\; L</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>\sqrt{\frac{{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; \&CenterDot;</span>{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; \&CenterDot;</span>{\mathrm{<span\; class="notranslate">\; a</span>}}_{\mathrm{<span\; class="notranslate">\; e</span>}}}{{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; )</span>$

Among them, i is the angle of the camshaft; d _s is the diameter of the grinding wheel; d _i is the equivalent diameter of the camshaft corresponding to every i degree; a _e is the cutting depth of the camshaft by the grinding wheel.

The instantaneous linear velocity v _i of the camshaft per i degree in formula (1) can be obtained according to the schematic diagram of the geometric relationship of the camshaft cut-in mill shown in Figure 3, specifically:

${\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}{\mathrm{<span\; class="notranslate">\; 60</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; \&pi;</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 4</span>}<span\; class="notranslate">\; )</span>$

Among them, i is the angle of the camshaft; d _i is the equivalent diameter of the camshaft corresponding to every i degree; n _i is the instantaneous speed of the camshaft every i degree.

It should be noted that the illustrations in the above embodiments are only for better understanding of the methods provided in the embodiments of the present invention, and cannot constitute a specific limitation of the present invention. Moreover, the above-mentioned preferred implementation modes will not affect each other, and the solution obtained by any combination of the preferred implementation modes shall fall within the scope of protection of the present invention.

In addition, in order to reflect the superiority of the present invention, the processing device provided by the embodiment of the present invention is compared with the existing processing device below. Specifically, take 16 cams and divide them equally into two groups, A and B. Group A is processed by constant temperature control, and group B is processed according to experience. The following experimental results are obtained, as shown in Figures 4 and 5: the experimental time of group A is nearly one-third less than that of group B; the cam in group A is not burned, and the cam in group B is burned to 75%; the surface of the cam in group A is burnt. The mean value of hardness is 74.713HV higher than the mean value of surface hardness of group B experimental cam; the mean value of surface roughness of group A test cam is 0.0917μm lower than that of group B test cam surface. It can be seen that the processing device provided by the present invention can effectively improve processing efficiency and processing quality under the premise of preventing camshaft burns.

In a second aspect, the present invention provides an embodiment of a constant temperature control method for camshaft grinding, as shown in FIG. 6 , including:

S601. The power measurement module measures the power of the motor in real time, and outputs the power, wherein the motor is a motor of a grinding wheel electric spindle for grinding a camshaft;

S602. The constant temperature control module receives the power output by the power measurement module, and calculates the current maximum temperature on the surface of the contact area between the grinding wheel and the camshaft according to the power and the preset constant temperature control model;

S603. The constant temperature control module compares the maximum temperature with a preset temperature threshold, and if it is determined that the maximum temperature is higher than or equal to the preset temperature threshold, control the motor to reduce the camshaft speed or reduce The depth of cut of the camshaft by the small grinding wheel.

During specific implementation, the method also includes:

If the constant temperature control module determines that the highest temperature is lower than the preset temperature threshold, it controls the motor to increase the camshaft speed, or increases the cutting depth of the camshaft by the grinding wheel.

During specific implementation, the method also includes:

If the constant temperature control module judges that the power is greater than the power threshold that needs to be trimmed, it controls the motor to stop working, and sends an alarm instruction for trimming or replacing the grinding wheel.

During specific implementation, the preset constant temperature control model is realized by the following formula, specifically:

${\mathrm{<span\; class="notranslate">\; \&theta;</span>}}_{\mathrm{<span\; class="notranslate">\; m</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; \&gamma;</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; P</span>}}{\mathrm{<span\; class="notranslate">\; b</span>}\mathrm{<span\; class="notranslate">\; c</span>}\mathrm{<span\; class="notranslate">\; \&rho;</span>}}\sqrt{{\mathrm{<span\; class="notranslate">\; L</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; /</span>{\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}$

Wherein, θ _m is the highest temperature on the surface of the contact area between the current grinding wheel and the camshaft; γ is the temperature correction coefficient of the constant temperature control model; P is the current power of the motor; b is the width of the camshaft; ρ is the material density of the camshaft; c is the specific heat capacity of the camshaft; i is the angle of the camshaft; L _i is the contact arc length corresponding to every i degree camshaft; v _i is the instantaneous linear velocity of every i degree camshaft.

During specific implementation, the contact arc length Li corresponding to each _i degree camshaft is realized by the following formula, specifically:

${\mathrm{<span\; class="notranslate">\; L</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>\sqrt{\frac{{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; a</span>}}_{\mathrm{<span\; class="notranslate">\; e</span>}}}{{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}}$

Among them, i is the angle of the camshaft; d _s is the diameter of the grinding wheel; d _i is the equivalent diameter of the camshaft corresponding to every i degree; a _e is the cutting depth of the grinding wheel on the camshaft;

The instantaneous linear velocity v of the camshaft per _i degree is realized by the following formula, specifically:

${\mathrm{<span\; class="notranslate">\; v</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; no</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}}{\mathrm{<span\; class="notranslate">\; 60</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; \&pi;</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>{\mathrm{<span\; class="notranslate">\; d</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}$

Among them, i is the angle of the camshaft; d _i is the equivalent diameter of the camshaft corresponding to every i degree; n _i is the instantaneous speed of the camshaft every i degree.

Since the structure and working principle of the constant temperature control device for camshaft grinding have been introduced in detail in the first aspect, in order to save space, the specific steps of the method will not be repeated here.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps not listed in a claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The invention can be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In a unit claim enumerating several means, several of these means can be embodied by one and the same item of hardware. The use of the words first, second, and third, etc. does not indicate any order. These words can be interpreted as names.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it can still be Modifications are made to the technical solutions described in the foregoing embodiments, or equivalent replacements are made to some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims (10)

1. the thermostatically-controlled equipment of a Camshaft Grinding processing, it is characterised in that including:

Power measurement module, for the power of measurement motor in real time, and exports described power, Wherein, described motor is the motor of the emery wheel electro spindle that camshaft carries out grinding；

Thermostatic control module, for receiving the power of described power measurement module output, and according to Described power and default thermostatic control model calculate current emery wheel and surface, camshaft contact area Maximum temperature；

Described thermostatic control module, is additionally operable to described maximum temperature and default temperature threshold ratio Relatively, if judging to know that described maximum temperature greater than or equal to described default temperature threshold, is then controlled Make described motor reduce camshaft speed or reduce the emery wheel cutting-in to camshaft.

2. device as claimed in claim 1, it is characterised in that

Described thermostatic control module, if being additionally operable to judge to know that described maximum temperature is less than described pre- If temperature threshold, then control described motor and improve camshaft speed, and increase emery wheel to cam The cutting-in of axle.

3. device as claimed in claim 1, it is characterised in that

Described thermostatic control module, if being additionally operable to judge to know described power more than needing finishing Power threshold, controls described motor and quits work, and sends the warning instruction changing emery wheel.

4. device as claimed in claim 1, it is characterised in that described default thermostatic control Model is realized by following formula, particularly as follows:

${\mathrm{\&theta;}}_m=\frac{\mathrm{\&gamma;}\&CenterDot;P}{bc\mathrm{\&rho;}}\sqrt{L_i^3/v_i}$

Wherein, θ_mMaximum temperature for current emery wheel Yu surface, camshaft contact area；γ is constant temperature control Simulation temperature correction coefficient；P is the power that described motor is current；B is the width of camshaft；ρ Density of material for camshaft；C is the specific heat capacity of camshaft；I is the angle of camshaft；L_iFor often The contact arc length that i degree camshaft is corresponding；v_iInstantaneous linear velocity for every i degree camshaft.

5. device as claimed in claim 4, it is characterised in that described every i degree camshaft is corresponding Contact arc length L_iRealized by following formula, particularly as follows:

$L_i=\sqrt{\frac{d_s\&CenterDot;d_i\&CenterDot;a_e}{d_s+d_i}}$

Wherein, i is the angle of camshaft；d_sDiameter for emery wheel；d_iConvex corresponding to every i degree The equivalent diameter of wheel shaft；a_eFor the emery wheel cutting-in to camshaft；

Instantaneous linear velocity v of described every i degree camshaft_iRealized by following formula, particularly as follows:

$v_i=\frac{n_i}{60}\&CenterDot;\mathrm{\&pi;}\&CenterDot;d_i$

Wherein, i is the angle of camshaft；d_iThe equivalent diameter of the camshaft corresponding to every i degree； n_iTransient speed for every i degree camshaft.

6. the constant-temperature control method of a Camshaft Grinding processing, it is characterised in that including:

Power measurement module measures the power of motor in real time, and is exported by described power, wherein, Described motor is the motor of the emery wheel electro spindle that camshaft carries out grinding；

Thermostatic control module receives the power of described power measurement module output, and according to described merit Rate and default thermostatic control model calculate the highest of current emery wheel and surface, camshaft contact area Temperature；

Described maximum temperature is compared, if sentencing by described thermostatic control module with the temperature threshold preset Break and know that described maximum temperature greater than or equal to described default temperature threshold, then controls described electricity Machine reduces camshaft speed, and reduces the emery wheel cutting-in to camshaft.

7. method as claimed in claim 6, it is characterised in that described method also includes:

If described thermostatic control module judges to know that described maximum temperature is less than described default temperature Threshold value, then control described motor and improve camshaft speed, and increase the emery wheel cutting-in to camshaft.

8. method as claimed in claim 6, it is characterised in that described method also includes:

If described thermostatic control module judges described power more than the power threshold needing finishing, Control described motor to quit work, and send finishing or change the warning instruction of emery wheel.

9. method as claimed in claim 6, it is characterised in that described default thermostatic control Model is realized by following formula, particularly as follows:

${\mathrm{\&theta;}}_m=\frac{\mathrm{\&gamma;}\&CenterDot;P}{bc\mathrm{\&rho;}}\sqrt{L_i^3/v_i}$

Wherein, θ_mMaximum temperature for current emery wheel Yu surface, camshaft contact area；γ is constant temperature control Simulation temperature correction coefficient；P is the power that described motor is current；B is the width of camshaft；ρ Density of material for camshaft；C is the specific heat capacity of camshaft；I is the angle of camshaft；L_iFor often The contact arc length that i degree camshaft is corresponding；v_iInstantaneous linear velocity for every i degree camshaft.

10. method as claimed in claim 9, it is characterised in that described every i degree camshaft is corresponding Contact arc length L_iRealized by following formula, particularly as follows:

$L_i=\sqrt{\frac{d_s\&CenterDot;d_i\&CenterDot;a_e}{d_s+d_i}}$

Wherein, i is the angle of camshaft；d_sDiameter for emery wheel；d_iConvex corresponding to every i degree The equivalent diameter of wheel shaft；a_eFor the emery wheel cutting-in to camshaft；

Instantaneous linear velocity v of described every i degree camshaft_iRealized by following formula, particularly as follows:

$v_i=\frac{n_i}{60}\&CenterDot;\mathrm{\&pi;}\&CenterDot;d_i$

Wherein, i is the angle of camshaft；d_iThe equivalent diameter of the camshaft corresponding to every i degree； n_iTransient speed for every i degree camshaft.