GB2132266A

GB2132266A - Cylinder block for an internal combustion engine

Info

Publication number: GB2132266A
Application number: GB08312683A
Authority: GB
Inventors: Gabriel Hrankovic
Original assignee: Ford Motor Co
Current assignee: Ford Motor Co
Priority date: 1982-12-23
Filing date: 1983-05-09
Publication date: 1984-07-04
Also published as: FR2538451B1; DE3247663C1; GB2132266B; FR2538451A1; GB8312683D0

Abstract

To enable the same cylinder block to be used in engines of different capacities, the coolant cavities 3 surrounding the cylinder bores 2 are made to suffice for the largest displacement envisaged and to avoid over cooling when the capacity is smaller the cavities 3 are partially filled by an insert of heat resistant plastics material 7. <IMAGE>

Description

SPECIFICATION Cylinder block for an internal combustion engine This invention relates to a cylinder block for an internal combustion engine.

In the design and construction of cylinder blocks for internal combustion engines, attempts have been made to envelope a cylinder bore with coolant cavities disposed circumferentially about each individual bore. Similar coolant cavities have been formed in the cylinder head. Such cylinder blocks are disclosed in German OS 2756006 and OS 2836810.

It is often necessary, in the design and construction of a cylinder, to consider possibility of boring a cylinder block of a specific construction to different sizes for internal combustion engines having different displacements and working at different capacities. Furthermore, the cylinder must be formed to be suitably rigid and vibration free in accordance with a particular engine power.

Each finished cylinder block therefore represents a comprise. For example, if a particular cylinder block is designed to function efficiently with a comparatively large piston displacement and correspondingly large coolant cavities, the same block will suffer overcooling when employed in an engine having a comparatively small piston displacement.

In accordance with the present invention, there is provided a cylinder block for an internal combustion engine having a cavity for a liquid coolant enveloping a cylinder bore, wherein a heat resistant material is inserted into the cavity to reduce the volume of the cavity.

By employing a cavity, the volume of which may be changed, it is possible that a cylinder block designed as a comprise in accordance with different requirements may subsequently have its cooling conditions adapted to correspond to the finished internal combustion engine in each particular case. For example, cavities which are constructed to be comparatively large for the piston displacement of a large internal combustion engine, may be reduced in size for an internal combustion engine having a smaller piston displacement such that no undesirable overcooling takes place. Furthermore, it is possible that an insertion of a heat resistant material may also enable the design of cylinder blocks with increased constructional strength and freedom from vibration as well as reducing the noise output level.

Conveniently, the heat resistant material is a plastics material.

By employing a suitable plastics material, it is possible that insertion of the heat resistant material may be carried out cheaply and easily.

The invention is described in.further detail with reference to an embodiment shown in the attached drawings, in which: Figure 1 is vertical longitudinal section through a cylinder block of an internal combusion engine, and Figure 2 is a vertical cross section along the line Il-Il of Figure 1.

In the Figures, a cylinder block 1 for an internal combustion engine is provided with cooling water cavities 3 enveloping the cylinder bores 2. Cooling water cavities are defined internally by the cylinder jackets 4 and, by the outer cylinder block wall 5. A coolant pump 6 disposed in a conventional manner in the front end wall area of the cylinder block 1.

A heat resistant plastics materials 7 is inserted in the lower parts on the cooling water cavities 3, partially filling the cavities. The level to which the heat resistant plastics material is inserted may preferably lie approximately at the same level as the lower edge of the piston in its top dead centre position. The free space required for the pump 6, may be ensured by a closure element.

In the case of a cylinder block produced by sand casting or low-pressure chill casting with cooling water cavities formed by lost cores the heat resistant plastics material 7 may be introduced into the cavity in a liquid form and hardened subsequent heat treatment.

In the case of a cylinder block produced by low pressure chill casting of light metal alloys and with downwardly open cooling water cavities, heat resistant plastics material may be formed as a mating closure member and fastened to the cylinder block in a sealed manner. In this embodiment, guide or baffle elements projecting into the upper area of the cooling water cavities (i.e. that area within which cooling water circulates) may be provided.

The heat resistant plastics material 7, may alternatively be used in the form of a fine granulate whose individual grains are bound together with heat treatment and form a porous mass through which water will flow at a reduced rate.

1. A cylinder block for an internal combustion engine having a cavity for a liquid coolant enveloping a cylinder bore, wherein a heat resistant material is inserted into the cavity to reduce the volume of the cavity.

2. A cylinder block as claimed in claim 1, wherein the heat resistant material is a plastics material.

3. A cylinder block as claimed in claim 1 or 2, wherein the heat resistant material is inserted into a lower part of the cavity.

4. A cylinder block as claimed in any of claims 1 to 3, wherein the cavity is formed by a lost-core casting process.

5. A cylinder block as claimed in any of the preceding claims, wherein the plastics material is introduced into the cavity in a liquid form and is hardened by subsequent heat treatment.

6. A cylinder block as claimed in any of claims 1 to 4, wherein the plastics material is formed as a closure member and sealingly secured to the cylinder block.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Cylinder block for an internal combustion engine This invention relates to a cylinder block for an internal combustion engine. In the design and construction of cylinder blocks for internal combustion engines, attempts have been made to envelope a cylinder bore with coolant cavities disposed circumferentially about each individual bore. Similar coolant cavities have been formed in the cylinder head. Such cylinder blocks are disclosed in German OS 2756006 and OS 2836810. It is often necessary, in the design and construction of a cylinder, to consider possibility of boring a cylinder block of a specific construction to different sizes for internal combustion engines having different displacements and working at different capacities. Furthermore, the cylinder must be formed to be suitably rigid and vibration free in accordance with a particular engine power. Each finished cylinder block therefore represents a comprise. For example, if a particular cylinder block is designed to function efficiently with a comparatively large piston displacement and correspondingly large coolant cavities, the same block will suffer overcooling when employed in an engine having a comparatively small piston displacement. In accordance with the present invention, there is provided a cylinder block for an internal combustion engine having a cavity for a liquid coolant enveloping a cylinder bore, wherein a heat resistant material is inserted into the cavity to reduce the volume of the cavity. By employing a cavity, the volume of which may be changed, it is possible that a cylinder block designed as a comprise in accordance with different requirements may subsequently have its cooling conditions adapted to correspond to the finished internal combustion engine in each particular case. For example, cavities which are constructed to be comparatively large for the piston displacement of a large internal combustion engine, may be reduced in size for an internal combustion engine having a smaller piston displacement such that no undesirable overcooling takes place. Furthermore, it is possible that an insertion of a heat resistant material may also enable the design of cylinder blocks with increased constructional strength and freedom from vibration as well as reducing the noise output level. Conveniently, the heat resistant material is a plastics material. By employing a suitable plastics material, it is possible that insertion of the heat resistant material may be carried out cheaply and easily. The invention is described in.further detail with reference to an embodiment shown in the attached drawings, in which: Figure 1 is vertical longitudinal section through a cylinder block of an internal combusion engine, and Figure 2 is a vertical cross section along the line Il-Il of Figure 1. In the Figures, a cylinder block 1 for an internal combustion engine is provided with cooling water cavities 3 enveloping the cylinder bores 2. Cooling water cavities are defined internally by the cylinder jackets 4 and, by the outer cylinder block wall 5. A coolant pump 6 disposed in a conventional manner in the front end wall area of the cylinder block 1. A heat resistant plastics materials 7 is inserted in the lower parts on the cooling water cavities 3, partially filling the cavities. The level to which the heat resistant plastics material is inserted may preferably lie approximately at the same level as the lower edge of the piston in its top dead centre position. The free space required for the pump 6, may be ensured by a closure element. In the case of a cylinder block produced by sand casting or low-pressure chill casting with cooling water cavities formed by lost cores the heat resistant plastics material 7 may be introduced into the cavity in a liquid form and hardened subsequent heat treatment. In the case of a cylinder block produced by low pressure chill casting of light metal alloys and with downwardly open cooling water cavities, heat resistant plastics material may be formed as a mating closure member and fastened to the cylinder block in a sealed manner. In this embodiment, guide or baffle elements projecting into the upper area of the cooling water cavities (i.e. that area within which cooling water circulates) may be provided. The heat resistant plastics material 7, may alternatively be used in the form of a fine granulate whose individual grains are bound together with heat treatment and form a porous mass through which water will flow at a reduced rate. CLAIMS

7. A cylinder block as claimed in any of claims 1 to 4, wherein the plastics material is introduced into the cavity in granular form and is subsequently bound together into a porous mass by heat-treatment.

8. A cylinder block substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.